Science Publishing Group: American Journal of Chemical Engineering: Table of Contents
<i> American Journal of Chemical Engineering (AJCHE) </i> provides a forum for sharing timely and up-to-date publication of scientific research and review articles. The journal publishes original full-length research papers in all areas related to chemical reaction engineering, environmental chemical engineering, and materials synthesis and processing. Reports of carefully executed experimental work, which is soundly interpreted are also welcome.The following categories are accepted: Original researches, case reports, reviews, technology papers and brief communications.
http://www.sciencepublishinggroup.com/j/ajche Science Publishing Group: American Journal of Chemical Engineering: Table of Contents
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American Journal of Chemical Engineering
American Journal of Chemical Engineering
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Optimum and Comparison of Theoretical & Experimental Results of an Industrial Secondary Reformer Reactor in Basra Fertilizers Plant at Different Operation Plant Efficiencies
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20130101.14
This study aims to evaluation the optimum performance of industrial Secondary Reformer reactor in the State Company of Fertilizers South Region in the Basra/Iraq relative to Different Operation Plant Efficiencies of ammonia plant at 100%, 70% and 65% through study the effect of different molar flowrates of air. The effect of air molar flowrates on the cooling water around the Secondary Reformer reactor have been described in this study. The analysis feed Process Gases compositions to the industrial Secondary Reformer reactor in the laboratory is used as data in the mathematical model then comprised these results with the values of industrial Reformat Gases which are tested in laboratory too. The optimum molar flow rate of air is specified at different efficiencies of Ammonia plant 100%,70% and 65%. The Secondary Reformer consists of two sections, the combustion and catalyst which is filled with nickel-containing reforming catalyst. It is placed after the primary reformer in ammonia plant at fertilizer plant. The Secondary Reformer reactor is used to produce Reformat Gases which are consisted from synthesis gas (Hydrogen and Carbon Monoxide) to Nitrogen mole ratio of 3 to 1. Finally, the optimum results of air molar flowrates at operation efficiency 100%, 70% and 65% found 1750.50, 1224 and 1136 Kmol/hr respectively.
This study aims to evaluation the optimum performance of industrial Secondary Reformer reactor in the State Company of Fertilizers South Region in the Basra/Iraq relative to Different Operation Plant Efficiencies of ammonia plant at 100%, 70% and 65% through study the effect of different molar flowrates of air. The effect of air molar flowrates on the cooling water around the Secondary Reformer reactor have been described in this study. The analysis feed Process Gases compositions to the industrial Secondary Reformer reactor in the laboratory is used as data in the mathematical model then comprised these results with the values of industrial Reformat Gases which are tested in laboratory too. The optimum molar flow rate of air is specified at different efficiencies of Ammonia plant 100%,70% and 65%. The Secondary Reformer consists of two sections, the combustion and catalyst which is filled with nickel-containing reforming catalyst. It is placed after the primary reformer in ammonia plant at fertilizer plant. The Secondary Reformer reactor is used to produce Reformat Gases which are consisted from synthesis gas (Hydrogen and Carbon Monoxide) to Nitrogen mole ratio of 3 to 1. Finally, the optimum results of air molar flowrates at operation efficiency 100%, 70% and 65% found 1750.50, 1224 and 1136 Kmol/hr respectively.
Optimum and Comparison of Theoretical & Experimental Results of an Industrial Secondary Reformer Reactor in Basra Fertilizers Plant at Different Operation Plant Efficiencies
doi:10.11648/j.ajche.20130101.14
American Journal of Chemical Engineering
2014-01-01
© Science Publishing Group
Ali Ashour AL-Dhfeery
Ala'a Abdulrazaq Jassem
Optimum and Comparison of Theoretical & Experimental Results of an Industrial Secondary Reformer Reactor in Basra Fertilizers Plant at Different Operation Plant Efficiencies
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© Science Publishing Group
High-Tech Industrial Development VS. Climate Change of the Sonora-Baja California Region of Mexico
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20130101.13
The industrialization of cities has generated considerable technological developments, with modern communication systems, specialized machinery and automated electronic systems. Large cities in Mexico, including Mexico City, Guadalajara, Monterrey and Tijuana, as well as others that have grown enormously, were including the cities of the border areas with the U.S., the central and southern part of the country. High technology developed is considered better to the economic and educational growth, but causing damage to the environment due to lack of the environmental control. This has led to the generation of variations in climatic factors, especially humidity, temperature and solar radiation, contributing to the climate change. A study conducted in the northwest of Mexico in the states of Sonora (Agua Prieta, Ciudad Obregon, Hermosillo, Nogales and San Luis Rio Colorado cities) and Baja California (Ensenada, Mexicali and Tijuana cities), where has noted that in the past 20 years, have increased the number of companies, determined by the industrial plant organizations. This research was made in the years of 2007 to 2009. In this study we show analysis of environmental degradation, influenced by a portion of emissions to water, air and soil of companies and around of it. Another important factor is that the industrialized city population tends to grow which causes an increase in emissions of CO and NOX from motor vehicles, solid and water waste of domestic, industrial and commercial activities. This generates a large pollution in certain periods of the year, mostly in the winter time when emissions are concentrated to only a few meters above the ground. Increases of deterioration of the environment near of companies were correlated with the industries established in the mentioned cities from 1990 to 2010 (with statistical analysis trend at year end). This was made measuring the increase concentration of major air pollutants with equipment and specialized measurement techniques, and also was monitoring the humidity and temperature variations and pH analysis characterization in water and soil near of the industrial plants, to know about the acidity levels.
The industrialization of cities has generated considerable technological developments, with modern communication systems, specialized machinery and automated electronic systems. Large cities in Mexico, including Mexico City, Guadalajara, Monterrey and Tijuana, as well as others that have grown enormously, were including the cities of the border areas with the U.S., the central and southern part of the country. High technology developed is considered better to the economic and educational growth, but causing damage to the environment due to lack of the environmental control. This has led to the generation of variations in climatic factors, especially humidity, temperature and solar radiation, contributing to the climate change. A study conducted in the northwest of Mexico in the states of Sonora (Agua Prieta, Ciudad Obregon, Hermosillo, Nogales and San Luis Rio Colorado cities) and Baja California (Ensenada, Mexicali and Tijuana cities), where has noted that in the past 20 years, have increased the number of companies, determined by the industrial plant organizations. This research was made in the years of 2007 to 2009. In this study we show analysis of environmental degradation, influenced by a portion of emissions to water, air and soil of companies and around of it. Another important factor is that the industrialized city population tends to grow which causes an increase in emissions of CO and NOX from motor vehicles, solid and water waste of domestic, industrial and commercial activities. This generates a large pollution in certain periods of the year, mostly in the winter time when emissions are concentrated to only a few meters above the ground. Increases of deterioration of the environment near of companies were correlated with the industries established in the mentioned cities from 1990 to 2010 (with statistical analysis trend at year end). This was made measuring the increase concentration of major air pollutants with equipment and specialized measurement techniques, and also was monitoring the humidity and temperature variations and pH analysis characterization in water and soil near of the industrial plants, to know about the acidity levels.
High-Tech Industrial Development VS. Climate Change of the Sonora-Baja California Region of Mexico
doi:10.11648/j.ajche.20130101.13
American Journal of Chemical Engineering
2014-01-01
© Science Publishing Group
Gustavo López Badilla
María Marcela Acosta Gomez
Elizabeth Romero Samaniego
Sandra Luz Toledo Perea
High-Tech Industrial Development VS. Climate Change of the Sonora-Baja California Region of Mexico
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© Science Publishing Group
Reservoir Formation Damage due to Mud Filtration
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Transport of particle suspensions in oil reservoirs is an essential phenomenon in many oil industry processes. Solid and liquid particles dispersed in the drilling fluid (mud) are trapped by the rock (porous medium) and permeability decline takes place during drilling fluid invasion into reservoir resulting in formation damage. The formation damage due to mud filtration is explained by erosion of external filter cake. Nevertheless, the stabilization is observed in core floods, which evidences internal erosion. A new mathematical model for detachment of particles is based on mechanical equilibrium of a particle positioned on the internal cake or matrix surface in the pore space. In the current work the analytical solution obtained for mud filtration with one particle capture mechanism with damage stabilization. The particle torque equilibrium is determined by the dimensionless ratio between the drag and normal forces acting on the particle. The maximum retention function of the dimensionless ratio closes system of governing equations for colloid transport through porous medium.
Transport of particle suspensions in oil reservoirs is an essential phenomenon in many oil industry processes. Solid and liquid particles dispersed in the drilling fluid (mud) are trapped by the rock (porous medium) and permeability decline takes place during drilling fluid invasion into reservoir resulting in formation damage. The formation damage due to mud filtration is explained by erosion of external filter cake. Nevertheless, the stabilization is observed in core floods, which evidences internal erosion. A new mathematical model for detachment of particles is based on mechanical equilibrium of a particle positioned on the internal cake or matrix surface in the pore space. In the current work the analytical solution obtained for mud filtration with one particle capture mechanism with damage stabilization. The particle torque equilibrium is determined by the dimensionless ratio between the drag and normal forces acting on the particle. The maximum retention function of the dimensionless ratio closes system of governing equations for colloid transport through porous medium.
Reservoir Formation Damage due to Mud Filtration
doi:10.11648/j.ajche.20130101.11
American Journal of Chemical Engineering
2014-01-01
© Science Publishing Group
Abdolreza Dabiri
Mohammad Afkhami
Hooman Fallah
Reservoir Formation Damage due to Mud Filtration
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© Science Publishing Group
Kinetic Model of pH effect on Bioremediation of Crude Petroleum Contaminated Soil. 1. Model Development
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Successful design and operation of a bioremediation process for soil contaminated with crude petroleum requires an in-depth understanding of the type of microorganisms involved, the specific reaction they perform, the factors that affect their performance, and their bioremediation kinetics. This paper attempts to develop the kinetic model for the pH being one of the major environmental factors that influence the bioavailability of contaminants, the availability of other nutrients, the activity of biological processes and hence the overall bioremediation kinetics of crude-petroleum contaminated soil. The pH model have been developed at the chemical and mathematical level with the basic assumptions that i) all side chains necessary for catalysis are in the correct protonation state; ii) an enzyme can exist in three degrees of protonation; iii) only one form of the enzyme is capable of binding substrate and catalyzing the reaction; and iv) the substrate is in great enough excess such that the equilibrium constant for the protonation of the free enzyme is the same as for the enzyme-substrate complex. The resulting model equations enable to obtain values of the equilibrium constants (K1 and K2) which are significant in determination of the optimal pH for bioremediation reaction rate.
Successful design and operation of a bioremediation process for soil contaminated with crude petroleum requires an in-depth understanding of the type of microorganisms involved, the specific reaction they perform, the factors that affect their performance, and their bioremediation kinetics. This paper attempts to develop the kinetic model for the pH being one of the major environmental factors that influence the bioavailability of contaminants, the availability of other nutrients, the activity of biological processes and hence the overall bioremediation kinetics of crude-petroleum contaminated soil. The pH model have been developed at the chemical and mathematical level with the basic assumptions that i) all side chains necessary for catalysis are in the correct protonation state; ii) an enzyme can exist in three degrees of protonation; iii) only one form of the enzyme is capable of binding substrate and catalyzing the reaction; and iv) the substrate is in great enough excess such that the equilibrium constant for the protonation of the free enzyme is the same as for the enzyme-substrate complex. The resulting model equations enable to obtain values of the equilibrium constants (K1 and K2) which are significant in determination of the optimal pH for bioremediation reaction rate.
Kinetic Model of pH effect on Bioremediation of Crude Petroleum Contaminated Soil. 1. Model Development
doi:10.11648/j.ajche.20130101.12
American Journal of Chemical Engineering
2014-01-01
© Science Publishing Group
G. A. O. Ajoku
M. K. Oduola
Kinetic Model of pH effect on Bioremediation of Crude Petroleum Contaminated Soil. 1. Model Development
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© Science Publishing Group
Three-Phase Mass Transfer: Application of the Pseudo-Homogeneous and Heterogeneous Models
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This paper surveyed the most important, well known two-phase mass transfer models, namely film-, film-penetration- and surface renewal models, applying them to describe the three-phase mass transfer rates at the gas-liquid interface. These models should enable the user to predict the mass transfer enhancement in the presence of a third, in the mass transport active, dispersed phase. Depending on the particle size of the dispersed phase, the pseudo-homogeneous and/or the heterogeneous model can be recommended for nanometer sized and micrometer sized particles, respectively. The effect of all important mass transport parameters, namely particle size, surface renewal frequency, diffusion depth, solubility coefficient, has been shown by typical figures. It has been analyzed how strongly depends the applicability of the homogeneous- or the heterogeneous models not only on the particle size but on the mass transport parameters. As case study, the measured and the predicted mass transfer rates have been investigated in nanofluids.
This paper surveyed the most important, well known two-phase mass transfer models, namely film-, film-penetration- and surface renewal models, applying them to describe the three-phase mass transfer rates at the gas-liquid interface. These models should enable the user to predict the mass transfer enhancement in the presence of a third, in the mass transport active, dispersed phase. Depending on the particle size of the dispersed phase, the pseudo-homogeneous and/or the heterogeneous model can be recommended for nanometer sized and micrometer sized particles, respectively. The effect of all important mass transport parameters, namely particle size, surface renewal frequency, diffusion depth, solubility coefficient, has been shown by typical figures. It has been analyzed how strongly depends the applicability of the homogeneous- or the heterogeneous models not only on the particle size but on the mass transport parameters. As case study, the measured and the predicted mass transfer rates have been investigated in nanofluids.
Three-Phase Mass Transfer: Application of the Pseudo-Homogeneous and Heterogeneous Models
doi:10.11648/j.ajche.20130101.15
American Journal of Chemical Engineering
2014-01-01
© Science Publishing Group
Endre Nagy
Krishna D. P. Nigam
Three-Phase Mass Transfer: Application of the Pseudo-Homogeneous and Heterogeneous Models
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© Science Publishing Group
Study of Kaolin for Synthesis of Aluminum Chloride
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20130102.11
Aluminum chloride enhanced polyacrylamide (AlCl3-PAM) hybrid polymer has been synthesized in this study. Aluminium chloride was synthesized with polyacrylamide via free radical solution polymerization to fabricate inorganic-organic hybrid polymer (AlCl3-PAM). A redox initiation system - (NH4)2S2O8 and NaHSO3 was used to initiate the polymerization at 50ºC in aqueous medium. Fourier Transform Infrared Spectrometer (FT-IR) was used to characterize aluminium chloride-polyacrylamide hybrid polymer by determining its functional groups exist in the hybrid polymer chain. Inorganic aluminium chloride salt was incorporated into the polyacrylamide to enhance the aggregation ability at kaolin particle interface. A physico-chemical method which is flocculation was used in this study to flocculate kaolin suspension. The effect of pH on the flocculation of kaolin suspension was studied between pH 5 to 7.5. The result showed the aluminium chloride-polyacrylamide (AlCl3-PAM) hybrid polymer was able to remove >99% of turbidity at pH 6.5 using 5 mg/L of dosage.
Aluminum chloride enhanced polyacrylamide (AlCl3-PAM) hybrid polymer has been synthesized in this study. Aluminium chloride was synthesized with polyacrylamide via free radical solution polymerization to fabricate inorganic-organic hybrid polymer (AlCl3-PAM). A redox initiation system - (NH4)2S2O8 and NaHSO3 was used to initiate the polymerization at 50ºC in aqueous medium. Fourier Transform Infrared Spectrometer (FT-IR) was used to characterize aluminium chloride-polyacrylamide hybrid polymer by determining its functional groups exist in the hybrid polymer chain. Inorganic aluminium chloride salt was incorporated into the polyacrylamide to enhance the aggregation ability at kaolin particle interface. A physico-chemical method which is flocculation was used in this study to flocculate kaolin suspension. The effect of pH on the flocculation of kaolin suspension was studied between pH 5 to 7.5. The result showed the aluminium chloride-polyacrylamide (AlCl3-PAM) hybrid polymer was able to remove >99% of turbidity at pH 6.5 using 5 mg/L of dosage.
Study of Kaolin for Synthesis of Aluminum Chloride
doi:10.11648/j.ajche.20130102.11
American Journal of Chemical Engineering
2014-01-01
© Science Publishing Group
Krishna Kumar
Omprakash Sahu
Study of Kaolin for Synthesis of Aluminum Chloride
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© Science Publishing Group
Effect of Fluid Viscosity on Asphalthene Deposition Rate during Turbulent Flow in Oil Wells
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20130102.13
The production and transportation of petroleum fluids will be severely affected by the deposition of suspended particles (i.e. asphaltenes, diamondoids, paraffin/wax, sand, etc.) in petroleum fluid production wells and/or transfer pipelines. Viscosity variations of petroleum fluid are an important phenomenon that could have significant effect on different properties related to petroleum fluid. Therefore, it is important to understand the effect of viscosity variations of petroleum fluid onthe deposition rate of suspended particles on the walls of the flowing channel. In this study, the analytical model for the prefouling behavior of suspended particles in production lines ischallenged in terms of viscosity changes that occur during the production in oil wells/tubings fora typical fluid sample experiencing particle deposition. Calculations of particle deposition rate inoil wells/tubings considering the change in viscosity for this typical oil sample is taken into consideration. The analysis presented in this report shows that rates of particle deposition (during petroleum fluid production) on the walls of the oil well/tubing is slightly effected by the viscosity variations that occur during the production conditions and it is also shown that the assumption of constant viscosity while deriving the analytical model for the deposition rate of particles on the walls of fluid conduits is quite a reasonable and valid assumption.
The production and transportation of petroleum fluids will be severely affected by the deposition of suspended particles (i.e. asphaltenes, diamondoids, paraffin/wax, sand, etc.) in petroleum fluid production wells and/or transfer pipelines. Viscosity variations of petroleum fluid are an important phenomenon that could have significant effect on different properties related to petroleum fluid. Therefore, it is important to understand the effect of viscosity variations of petroleum fluid onthe deposition rate of suspended particles on the walls of the flowing channel. In this study, the analytical model for the prefouling behavior of suspended particles in production lines ischallenged in terms of viscosity changes that occur during the production in oil wells/tubings fora typical fluid sample experiencing particle deposition. Calculations of particle deposition rate inoil wells/tubings considering the change in viscosity for this typical oil sample is taken into consideration. The analysis presented in this report shows that rates of particle deposition (during petroleum fluid production) on the walls of the oil well/tubing is slightly effected by the viscosity variations that occur during the production conditions and it is also shown that the assumption of constant viscosity while deriving the analytical model for the deposition rate of particles on the walls of fluid conduits is quite a reasonable and valid assumption.
Effect of Fluid Viscosity on Asphalthene Deposition Rate during Turbulent Flow in Oil Wells
doi:10.11648/j.ajche.20130102.13
American Journal of Chemical Engineering
2014-01-01
© Science Publishing Group
Gholamreza Vakili-Nezhaad
Nabeel Al-Rawahi
G. Ali Mansoori
Amin Fatemi
Effect of Fluid Viscosity on Asphalthene Deposition Rate during Turbulent Flow in Oil Wells
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© Science Publishing Group
Effects of Surfactant on Bubble Size Distribution and Gas Hold-up in a Bubble Column
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20130102.14
This study investigates the influence of two surfactants –a non-ionic (Tween20) and a zwitterionic (Cocoamidopropyl Betaine) – upon the gas-liquid hydrodynamics in a bubble column. These kinds of substances can have an important influence upon the gas-liquid hydrodynamics, specifically on the bubble size and gas hold-up. Bubble diameters were measured photographically in a bubble column, which was operating in the homogeneous regime with air and aqueous surfactant solutions. The bubble size and gas hold-up data were determined for several values of the superficial gas velocity (0.13, 0.26 and 0.5 cm/s). On the other hand, bubble diameter was determined for different values of surfactant concentration (0.02, 0.05 and 0.1 %vol). At superficial gas velocity below 0.26 cm/s, addition of surfactant in air-water has low influence on bubble size, whereas higher gas velocity addition of surfactant increases the number of bubble. In surfactant solutions (in comparison with pour water), resulted in an increase in number of bubble and a rough decrease in Sauter mean bubble diameter. Bubbles tend to become smaller with decreasing surface tension of water. Therefore, surfactant existence increases the gas hold-up. Further, gas holdup increased when gas bubbles movement increased.
This study investigates the influence of two surfactants –a non-ionic (Tween20) and a zwitterionic (Cocoamidopropyl Betaine) – upon the gas-liquid hydrodynamics in a bubble column. These kinds of substances can have an important influence upon the gas-liquid hydrodynamics, specifically on the bubble size and gas hold-up. Bubble diameters were measured photographically in a bubble column, which was operating in the homogeneous regime with air and aqueous surfactant solutions. The bubble size and gas hold-up data were determined for several values of the superficial gas velocity (0.13, 0.26 and 0.5 cm/s). On the other hand, bubble diameter was determined for different values of surfactant concentration (0.02, 0.05 and 0.1 %vol). At superficial gas velocity below 0.26 cm/s, addition of surfactant in air-water has low influence on bubble size, whereas higher gas velocity addition of surfactant increases the number of bubble. In surfactant solutions (in comparison with pour water), resulted in an increase in number of bubble and a rough decrease in Sauter mean bubble diameter. Bubbles tend to become smaller with decreasing surface tension of water. Therefore, surfactant existence increases the gas hold-up. Further, gas holdup increased when gas bubbles movement increased.
Effects of Surfactant on Bubble Size Distribution and Gas Hold-up in a Bubble Column
doi:10.11648/j.ajche.20130102.14
American Journal of Chemical Engineering
2014-01-01
© Science Publishing Group
Maedeh Asari
Faramarz Hormozi
Effects of Surfactant on Bubble Size Distribution and Gas Hold-up in a Bubble Column
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© Science Publishing Group
Simulation of Ammonia Synthesis
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Ammonia is prodeuced to give a final product named urea which is a very important fertilizer for higher nitrogen content.Several processes has been invented for optimum production of ammonia. Now-a-days, Ammonia production is mainly done by Haber process in which nitrogen andhydrogen react in the presence of an iron catalyst to form ammonia. The hydrogen is formedby reacting natural gas and steam at high temperatures and the nitrogen is supplied from theair. Other gases (such as water and carbon dioxide) are removed from the gas stream andthe nitrogen and hydrogen passed over an iron catalyst at high temperature and pressure toform the ammonia. In our work, simulation of ammonia synthesis process is done on Aspen Hysys 7.1. By using 1.07e+005kmole/hr methane, 2.8e+005kmole/hr hydrogen, 1.02e+005kmole/hr nitrogen, we haveproduced4.6e+004 kmole/hr ammonia.It has also been found that ammonia production increases with the rise of pressure of fresh feed.
Ammonia is prodeuced to give a final product named urea which is a very important fertilizer for higher nitrogen content.Several processes has been invented for optimum production of ammonia. Now-a-days, Ammonia production is mainly done by Haber process in which nitrogen andhydrogen react in the presence of an iron catalyst to form ammonia. The hydrogen is formedby reacting natural gas and steam at high temperatures and the nitrogen is supplied from theair. Other gases (such as water and carbon dioxide) are removed from the gas stream andthe nitrogen and hydrogen passed over an iron catalyst at high temperature and pressure toform the ammonia. In our work, simulation of ammonia synthesis process is done on Aspen Hysys 7.1. By using 1.07e+005kmole/hr methane, 2.8e+005kmole/hr hydrogen, 1.02e+005kmole/hr nitrogen, we haveproduced4.6e+004 kmole/hr ammonia.It has also been found that ammonia production increases with the rise of pressure of fresh feed.
Simulation of Ammonia Synthesis
doi:10.11648/j.ajche.20130103.11
American Journal of Chemical Engineering
2014-01-01
© Science Publishing Group
M. R. Amin
S. Sharear
N. Siddique
Shaidul Islam
Simulation of Ammonia Synthesis
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© Science Publishing Group
Image Analysis Technique as a Tool for Extracting Features from the Copper Surface Froth in the Flotation Process
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20130104.12
The froth can be adopted as an indicator of the performance of flotation processes. The study of froth image structure would enable us to establish a number of parameters from which could convey the froth characteristics. To monitor the operating performance of the floatation cell by machine vision system, it is crucial to identify and extract those features that are descriptive of the surface froth. Consequently, it can provide interdependency between the froth characteristics with the operating conditions on one hand (e.g., aeration rate, froth depth, chemical compound and pH variation) and the cell parameters performance on the other hand, as well (e.g., copper grade, recovery and solid contents). The aim of the present study is to examine the copper froth characteristics, by adopting an image analysis technique and hence evaluating froth features such as the average bubble size, bubbles distribution, bubble shape features, bubble elongation factor, image average color and the color distribution. Owing to the intricacy aspect of the froth structure and in order to match properly between the real froth and the segmentation images, this algorithm adopts features similar to proper filters in the pre-processing stage, edge detection functions, threshold functions and different mathematical morphology models. The findings of this work reveal that the size and shape of the froth bubbles plays an important role in classifying the froth. Hence, it is possible to incorporate such features for either evaluating the flotation cell performance or adopting it for the automatic on-line control of the flotation process. The findings of this research could also be implemented towards the training of the operators.
The froth can be adopted as an indicator of the performance of flotation processes. The study of froth image structure would enable us to establish a number of parameters from which could convey the froth characteristics. To monitor the operating performance of the floatation cell by machine vision system, it is crucial to identify and extract those features that are descriptive of the surface froth. Consequently, it can provide interdependency between the froth characteristics with the operating conditions on one hand (e.g., aeration rate, froth depth, chemical compound and pH variation) and the cell parameters performance on the other hand, as well (e.g., copper grade, recovery and solid contents). The aim of the present study is to examine the copper froth characteristics, by adopting an image analysis technique and hence evaluating froth features such as the average bubble size, bubbles distribution, bubble shape features, bubble elongation factor, image average color and the color distribution. Owing to the intricacy aspect of the froth structure and in order to match properly between the real froth and the segmentation images, this algorithm adopts features similar to proper filters in the pre-processing stage, edge detection functions, threshold functions and different mathematical morphology models. The findings of this work reveal that the size and shape of the froth bubbles plays an important role in classifying the froth. Hence, it is possible to incorporate such features for either evaluating the flotation cell performance or adopting it for the automatic on-line control of the flotation process. The findings of this research could also be implemented towards the training of the operators.
Image Analysis Technique as a Tool for Extracting Features from the Copper Surface Froth in the Flotation Process
doi:10.11648/j.ajche.20130104.12
American Journal of Chemical Engineering
2014-01-01
© Science Publishing Group
Nasser Saghatoleslami
Hajir Karimi
Image Analysis Technique as a Tool for Extracting Features from the Copper Surface Froth in the Flotation Process
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© Science Publishing Group
Use of Fatty Acid Methyl Esters as Biocomponents for Diesel Fuels and for Preparation of Cetane Number Improvers
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20130104.11
Up to 15% of fatty acid methyl esters (FAMEs) have been used as biocomponents for the manufacture of biodiesel fuels corresponding to the requirements of EN 590-09. Applying nitration with various agents has been obtained additives reducing the time delay of self-ignition (TDSI) of diesel fuels containing 20% light catalytic gas oil. The nitro products thus obtained increase also the resistance of the diesel fuel towards oxidation.
Up to 15% of fatty acid methyl esters (FAMEs) have been used as biocomponents for the manufacture of biodiesel fuels corresponding to the requirements of EN 590-09. Applying nitration with various agents has been obtained additives reducing the time delay of self-ignition (TDSI) of diesel fuels containing 20% light catalytic gas oil. The nitro products thus obtained increase also the resistance of the diesel fuel towards oxidation.
Use of Fatty Acid Methyl Esters as Biocomponents for Diesel Fuels and for Preparation of Cetane Number Improvers
doi:10.11648/j.ajche.20130104.11
American Journal of Chemical Engineering
2014-01-01
© Science Publishing Group
Fahed Salem Khamis
Todor Vasilev Palichev
Galina Grigorova Khamis
Jabbar Lashkeri Ismail Agha
Use of Fatty Acid Methyl Esters as Biocomponents for Diesel Fuels and for Preparation of Cetane Number Improvers
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69
69
2014-01-01
2014-01-01
10.11648/j.ajche.20130104.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20130104.11
© Science Publishing Group
Life Cycle Inventory of a Biodiesel Production Unit
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140201.11
Carbon dioxide is one of the main compounds pointed as a cause for climate changes, mainly due to the accelerated use of fossil fuels. In order to measure the consumption of the resources that generate carbon dioxide and verify these compounds emissions, quantitative studies aren’t sufficient, but it is needed a proportion relation with the environmental impact. Life cycle analysis studies are used to establish parameters to this relation, orientating which is the best way to be followed and also estimating, as close as possible to the reality, the degree of impacts that can be caused. This paper studies a biodiesel plant in Brazil, using the model described in ISO’s 14040 group to perform a life cycle inventory. Biodiesel is an alternative renewable fuel to the common diesel. The biodiesel has been considered a “clean” fuel, however its fabrication process involves environmental impacts. Hence, the objective of this study is to address those impacts, from a theoretical biodiesel plant data, and provide background information, in the form a life cycle inventory (LCI), to allow further comparisons between biodiesel production and other fuels. Finally, a full LCI for biodiesel is completed and it is concluded that, qualitatively, the environmental impact generated are similar to other commonly used fuels.
Carbon dioxide is one of the main compounds pointed as a cause for climate changes, mainly due to the accelerated use of fossil fuels. In order to measure the consumption of the resources that generate carbon dioxide and verify these compounds emissions, quantitative studies aren’t sufficient, but it is needed a proportion relation with the environmental impact. Life cycle analysis studies are used to establish parameters to this relation, orientating which is the best way to be followed and also estimating, as close as possible to the reality, the degree of impacts that can be caused. This paper studies a biodiesel plant in Brazil, using the model described in ISO’s 14040 group to perform a life cycle inventory. Biodiesel is an alternative renewable fuel to the common diesel. The biodiesel has been considered a “clean” fuel, however its fabrication process involves environmental impacts. Hence, the objective of this study is to address those impacts, from a theoretical biodiesel plant data, and provide background information, in the form a life cycle inventory (LCI), to allow further comparisons between biodiesel production and other fuels. Finally, a full LCI for biodiesel is completed and it is concluded that, qualitatively, the environmental impact generated are similar to other commonly used fuels.
Life Cycle Inventory of a Biodiesel Production Unit
doi:10.11648/j.ajche.20140201.11
American Journal of Chemical Engineering
2014-01-01
© Science Publishing Group
Priscilla Sieira
Erick B.F. Galante
Wilma A. Gonzales
Assed Haddad
Life Cycle Inventory of a Biodiesel Production Unit
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7
7
2014-01-01
2014-01-01
10.11648/j.ajche.20140201.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140201.11
© Science Publishing Group
Determination Effects of Process Parameters on CO2 Reactive absorption System by Mathematical Modeling
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140202.11
A steady state model for CO2- reactive absorption system was developed based on principle of mass transfer and chemical reaction. The pseudo-first order model is assumed and reversibility of chemical reaction was also neglected. The continuity model equation in term of material balance with chemical reaction across an elemental stage K on CO2 was developed. The model consists of system of linear simultaneous equations, and the equations representing the composition of CO2 in both liquid and gas phases were solved. The simulation studies were performed to investigate the effect of changing various process variables such as number of plate, gas flow rate, and CO2 composition in the feed vapor.
A steady state model for CO2- reactive absorption system was developed based on principle of mass transfer and chemical reaction. The pseudo-first order model is assumed and reversibility of chemical reaction was also neglected. The continuity model equation in term of material balance with chemical reaction across an elemental stage K on CO2 was developed. The model consists of system of linear simultaneous equations, and the equations representing the composition of CO2 in both liquid and gas phases were solved. The simulation studies were performed to investigate the effect of changing various process variables such as number of plate, gas flow rate, and CO2 composition in the feed vapor.
Determination Effects of Process Parameters on CO2 Reactive absorption System by Mathematical Modeling
doi:10.11648/j.ajche.20140202.11
American Journal of Chemical Engineering
2014-05-28
© Science Publishing Group
Adeyinka Sikiru Yusuff
Charles Uliukhifo Omohimoria
Kayode Augustine Idowu
Determination Effects of Process Parameters on CO2 Reactive absorption System by Mathematical Modeling
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13
13
2014-05-28
2014-05-28
10.11648/j.ajche.20140202.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140202.11
© Science Publishing Group
Modelling of Straitened Sedimentation Process in Bidisperse Suspension with Inter-Fractional Coagulation
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140202.12
In this paper we study the general characteristics of deposition of large particles (or aggregates) that result from the mutual aggregation of small and large fractions in bidisperse (or double fractional) suspension. We give equations of motion and change in mass of the large particle in the presence of inter-fractional coagulation process and effect of straitened sedimentation. In the limiting Stokes and Newton modes (relevant for small and large Reynolds numbers) we have movement formulas for speed of sedimentation and their analysis. Discuss some of the results of calculations obtained by numerical integration of the equations of motion of a large particle in suspension.
In this paper we study the general characteristics of deposition of large particles (or aggregates) that result from the mutual aggregation of small and large fractions in bidisperse (or double fractional) suspension. We give equations of motion and change in mass of the large particle in the presence of inter-fractional coagulation process and effect of straitened sedimentation. In the limiting Stokes and Newton modes (relevant for small and large Reynolds numbers) we have movement formulas for speed of sedimentation and their analysis. Discuss some of the results of calculations obtained by numerical integration of the equations of motion of a large particle in suspension.
Modelling of Straitened Sedimentation Process in Bidisperse Suspension with Inter-Fractional Coagulation
doi:10.11648/j.ajche.20140202.12
American Journal of Chemical Engineering
2014-06-12
© Science Publishing Group
Tulegen Amanbaev
Modelling of Straitened Sedimentation Process in Bidisperse Suspension with Inter-Fractional Coagulation
2
2
20
20
2014-06-12
2014-06-12
10.11648/j.ajche.20140202.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140202.12
© Science Publishing Group
Modeling and Analysis of Biogas Generation Rate Sensitivity to Initial-pH, Leachate-Level and Ash-Loading during Anaerobic Biodegradation of Organic Solid Waste
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140203.11
Anaerobic biodegradation of solid waste food-residues mixed with fruit-waste was carried out at mesophilic conditions. The goal was to model the sensitivity of biogas generation rate to initial-pH, leachate-level and ash-loading. Two process parameters were analyzed at centre-points while the third factor was set at low-, mid- and high-levels. The simulation results showed that at initial-pH of 5 (low-level), the biogas generation rate was more sensitive to ash-loading than at high-level of initial-pH values. The minimum and maximum attainable biogas generation rates due to perturbations in ash-loading were 0.79 and 1.89 mL/min, respectively, representing a difference of 1.10 mL/min. A comparison using sensitivity quotient revealed that decreasing leachate-level had a stronger effect on biogas generation rate than increasing it. It was also found that the biodegradation process was over four-times more sensitive to variations in initial-pH than in ash-loading while it was over seven-times more sensitive to variations in initial-pH than in leachate-level. It was concluded that the sensitivity of biogas generation rate was highest to variations in initial-pH and least to variations in leachate-level.
Anaerobic biodegradation of solid waste food-residues mixed with fruit-waste was carried out at mesophilic conditions. The goal was to model the sensitivity of biogas generation rate to initial-pH, leachate-level and ash-loading. Two process parameters were analyzed at centre-points while the third factor was set at low-, mid- and high-levels. The simulation results showed that at initial-pH of 5 (low-level), the biogas generation rate was more sensitive to ash-loading than at high-level of initial-pH values. The minimum and maximum attainable biogas generation rates due to perturbations in ash-loading were 0.79 and 1.89 mL/min, respectively, representing a difference of 1.10 mL/min. A comparison using sensitivity quotient revealed that decreasing leachate-level had a stronger effect on biogas generation rate than increasing it. It was also found that the biodegradation process was over four-times more sensitive to variations in initial-pH than in ash-loading while it was over seven-times more sensitive to variations in initial-pH than in leachate-level. It was concluded that the sensitivity of biogas generation rate was highest to variations in initial-pH and least to variations in leachate-level.
Modeling and Analysis of Biogas Generation Rate Sensitivity to Initial-pH, Leachate-Level and Ash-Loading during Anaerobic Biodegradation of Organic Solid Waste
doi:10.11648/j.ajche.20140203.11
American Journal of Chemical Engineering
2014-06-12
© Science Publishing Group
William Wanasolo
Samwel Manyele
John Makunza
Modeling and Analysis of Biogas Generation Rate Sensitivity to Initial-pH, Leachate-Level and Ash-Loading during Anaerobic Biodegradation of Organic Solid Waste
2
3
27
27
2014-06-12
2014-06-12
10.11648/j.ajche.20140203.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140203.11
© Science Publishing Group
Solid State Fermentation Process for Polygalacturonase Production Using Cashew Apple
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140203.12
The aim of this work was the optimization of solid state fermentation for polygalacturonases production using cashew apple dry bagasse as substrate and Aspergillus niger CCT0916. For this, it was observed the influence of moisture content, spore concentration, ammonium sulfate concentration and fermentation temperature on polygalacturonase activity. It was observed that moisture is the limiting factor in the process. Maximum polygalacturonase activity (33 U/g) was obtained with 50 %w.b initial moisture, 106 spores/g, 1.5 %(w/w) ammonium sulfate and temperature of 35°C. The models for 21, 29 and 54-hours of fermentation were statistically significant at 95% confidence level.
The aim of this work was the optimization of solid state fermentation for polygalacturonases production using cashew apple dry bagasse as substrate and Aspergillus niger CCT0916. For this, it was observed the influence of moisture content, spore concentration, ammonium sulfate concentration and fermentation temperature on polygalacturonase activity. It was observed that moisture is the limiting factor in the process. Maximum polygalacturonase activity (33 U/g) was obtained with 50 %w.b initial moisture, 106 spores/g, 1.5 %(w/w) ammonium sulfate and temperature of 35°C. The models for 21, 29 and 54-hours of fermentation were statistically significant at 95% confidence level.
Solid State Fermentation Process for Polygalacturonase Production Using Cashew Apple
doi:10.11648/j.ajche.20140203.12
American Journal of Chemical Engineering
2014-08-07
© Science Publishing Group
Siumara R. Alcântara
Flávio L. H. da Silva
Solid State Fermentation Process for Polygalacturonase Production Using Cashew Apple
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34
34
2014-08-07
2014-08-07
10.11648/j.ajche.20140203.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140203.12
© Science Publishing Group
The Influence of Stereochemistry of the Active Compounds on Fluoride Adsorption Efficiency of the Plant Biomass
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140204.12
Several studies have reported various defluoridation capabilities of plant biomasses. The resultant variations in fluoride removal capacities are associated with the presence of different types of active functional groups in the respective biomasses. This study reports of the fluoride removal efficiencies of sisal leaf biomass in comparison. Comparison with other plant biomasses were made and hence the fluoride removal efficiencies of maize leaf (ML), goose grass (GG), banana false stem (BFS), Aloe vera (AV), untreated sisal fibre (USF) and sisal pith (SP) with similar active functional groups but different stereochemistry and solubility of the active compounds are reported. A portion of 0.5 g of each biomass was mixed with a 10 mg/l fluoride solution in a 10 ml portions under the same experimental conditions. The maximum fluoride removal capacity of sisal fibre biomass was found to be 26.6 %. By comparison, the fluoride removal efficiencies of ML, GG, BFS, AV, USF and SP were found to be, 4.1, 4.6, 7.1, 26.6, 29.4 and 47.3 % respectively. This suggests that, stereochemistry and solubility of the active compounds have a significant role to play in water defluoridation by plant biomasses, and thus, knowledge of the stereochemistry and solubility of the active compounds in plant biomass is very important to fully unlock biomass’ defluoridation potentials.
Several studies have reported various defluoridation capabilities of plant biomasses. The resultant variations in fluoride removal capacities are associated with the presence of different types of active functional groups in the respective biomasses. This study reports of the fluoride removal efficiencies of sisal leaf biomass in comparison. Comparison with other plant biomasses were made and hence the fluoride removal efficiencies of maize leaf (ML), goose grass (GG), banana false stem (BFS), Aloe vera (AV), untreated sisal fibre (USF) and sisal pith (SP) with similar active functional groups but different stereochemistry and solubility of the active compounds are reported. A portion of 0.5 g of each biomass was mixed with a 10 mg/l fluoride solution in a 10 ml portions under the same experimental conditions. The maximum fluoride removal capacity of sisal fibre biomass was found to be 26.6 %. By comparison, the fluoride removal efficiencies of ML, GG, BFS, AV, USF and SP were found to be, 4.1, 4.6, 7.1, 26.6, 29.4 and 47.3 % respectively. This suggests that, stereochemistry and solubility of the active compounds have a significant role to play in water defluoridation by plant biomasses, and thus, knowledge of the stereochemistry and solubility of the active compounds in plant biomass is very important to fully unlock biomass’ defluoridation potentials.
The Influence of Stereochemistry of the Active Compounds on Fluoride Adsorption Efficiency of the Plant Biomass
doi:10.11648/j.ajche.20140204.12
American Journal of Chemical Engineering
2014-08-12
© Science Publishing Group
Hezron T Mwakabona
Revocatus L Machunda
Karoli N Njau
The Influence of Stereochemistry of the Active Compounds on Fluoride Adsorption Efficiency of the Plant Biomass
2
4
47
47
2014-08-12
2014-08-12
10.11648/j.ajche.20140204.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140204.12
© Science Publishing Group
Analysis of Chemical Contaminations in Natural Resources
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140204.13
Natural forest resources like Sundarbans mangroves in Asia including Bangladesh, India, and East Africa previously contained a much fuller range of species (Seidensticker, and Hai, 1983; Khan, 1997). In the Southeast Asian region, species diversity of mangroves was previously much higher, where approximately two-thirds of all species and 70% of the major vegetation types with 15% of terrestrial species in the Bangladesh-India-Malayan realm have already been destroyed (Ellison, 1998, 2000). Despite this designation, this natural forest resources (Sundarbans) in Bangladesh has been facing tremendous problems, including that of dieback (top-dying), human destructions, deforestations, illicit fellings, miss-management of the main tree species (Heritiera fomes) which is affecting millions of trees. The cause of this dieback is still not well understood unknown. The present work has investigated one of the possible factors that might be causing this top-dying, namely the concentrations of various chemical elements present in the sediments, particularly heavy metals, though other chemical parameters such as the pH, salinity, moisture content of the sediment and nutrient status were also assessed. Tree height and trunk diameter were determined as indications of tree growth, counts of seedlings and saplings were made to assess regeneration success, and the intensity of top-dying within the sampled plots was recorded on a rank scale. However, the present results have showed that Sn, Exchangeable K, soil pH, Pb , Zn and Ni could be directly linked with top-dying disease of Heritiera fomes (Sundri) in Sundarbans, probably particularly by weakening the vigor of the trees and people and allowing other factors such as pathological agents to attack the plants and surrounding people in Sundarbans, Bangladesh (Awal, 2014). In fact, from since then and still now, the natural resource of Bangladesh like Sundarbans is being disturbed ecologically by human destruction.
Natural forest resources like Sundarbans mangroves in Asia including Bangladesh, India, and East Africa previously contained a much fuller range of species (Seidensticker, and Hai, 1983; Khan, 1997). In the Southeast Asian region, species diversity of mangroves was previously much higher, where approximately two-thirds of all species and 70% of the major vegetation types with 15% of terrestrial species in the Bangladesh-India-Malayan realm have already been destroyed (Ellison, 1998, 2000). Despite this designation, this natural forest resources (Sundarbans) in Bangladesh has been facing tremendous problems, including that of dieback (top-dying), human destructions, deforestations, illicit fellings, miss-management of the main tree species (Heritiera fomes) which is affecting millions of trees. The cause of this dieback is still not well understood unknown. The present work has investigated one of the possible factors that might be causing this top-dying, namely the concentrations of various chemical elements present in the sediments, particularly heavy metals, though other chemical parameters such as the pH, salinity, moisture content of the sediment and nutrient status were also assessed. Tree height and trunk diameter were determined as indications of tree growth, counts of seedlings and saplings were made to assess regeneration success, and the intensity of top-dying within the sampled plots was recorded on a rank scale. However, the present results have showed that Sn, Exchangeable K, soil pH, Pb , Zn and Ni could be directly linked with top-dying disease of Heritiera fomes (Sundri) in Sundarbans, probably particularly by weakening the vigor of the trees and people and allowing other factors such as pathological agents to attack the plants and surrounding people in Sundarbans, Bangladesh (Awal, 2014). In fact, from since then and still now, the natural resource of Bangladesh like Sundarbans is being disturbed ecologically by human destruction.
Analysis of Chemical Contaminations in Natural Resources
doi:10.11648/j.ajche.20140204.13
American Journal of Chemical Engineering
2014-08-19
© Science Publishing Group
Awal Mohd Abdul
Analysis of Chemical Contaminations in Natural Resources
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2014-08-19
2014-08-19
10.11648/j.ajche.20140204.13
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140204.13
© Science Publishing Group
Preconcentration of Copper, Cadmium and Lead on Amberlite XAD-4 Resin Functionalized with 2-Hydroxynaphthalene-1-Carbanaldehydethiosemicarbazone and their Determination in Green Tea Leaves by GF-AAS
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140204.11
2-hydroxynaphthalene-1-carbanaldehydethiosemicarbazone loaded XAD-4 chelating resin was synthesized and characterized by FT-IR technique. The use of synthesized resin for preconcentrating Cu2+, Cd2+ and Pb2+ ions was studied using graphite furnace atomic absorption spectrometry (GF-AAS) for metal monitoring in the environmental samples. Various parameters, such as pH, eluent type and concentration, flow rate of sample solution and matrix interference effect on the retention of the metal ions have been studied. The optimum pH for the sorption of the above mentioned metal ions was about 8. Optimum flow rate for quantitative sorption of the metal ions on functionalized resin was found to be 10 mL min-1 whereas 2 M HNO3 was selected as the eluent for quantitative release of the three metal ions from the resin column. Under optimum conditions, recovery of all metal ions was found to be quantitative. The validation of the procedure was carried out by analysis of certified reference materials. The newly developed method was applied to the separation, preconcentration and determination of Cu2+, Cd2+ and Pb2+ in tea leaves collected from the tea gardens of Moulovibazar district of Bangladesh.
2-hydroxynaphthalene-1-carbanaldehydethiosemicarbazone loaded XAD-4 chelating resin was synthesized and characterized by FT-IR technique. The use of synthesized resin for preconcentrating Cu2+, Cd2+ and Pb2+ ions was studied using graphite furnace atomic absorption spectrometry (GF-AAS) for metal monitoring in the environmental samples. Various parameters, such as pH, eluent type and concentration, flow rate of sample solution and matrix interference effect on the retention of the metal ions have been studied. The optimum pH for the sorption of the above mentioned metal ions was about 8. Optimum flow rate for quantitative sorption of the metal ions on functionalized resin was found to be 10 mL min-1 whereas 2 M HNO3 was selected as the eluent for quantitative release of the three metal ions from the resin column. Under optimum conditions, recovery of all metal ions was found to be quantitative. The validation of the procedure was carried out by analysis of certified reference materials. The newly developed method was applied to the separation, preconcentration and determination of Cu2+, Cd2+ and Pb2+ in tea leaves collected from the tea gardens of Moulovibazar district of Bangladesh.
Preconcentration of Copper, Cadmium and Lead on Amberlite XAD-4 Resin Functionalized with 2-Hydroxynaphthalene-1-Carbanaldehydethiosemicarbazone and their Determination in Green Tea Leaves by GF-AAS
doi:10.11648/j.ajche.20140204.11
American Journal of Chemical Engineering
2014-08-07
© Science Publishing Group
A. K. M. Atique Ullah
Mahmuda Akter
Md. Roksenul Anam
Md. Shakhawat Hossain Firoz
Preconcentration of Copper, Cadmium and Lead on Amberlite XAD-4 Resin Functionalized with 2-Hydroxynaphthalene-1-Carbanaldehydethiosemicarbazone and their Determination in Green Tea Leaves by GF-AAS
2
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41
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2014-08-07
2014-08-07
10.11648/j.ajche.20140204.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140204.11
© Science Publishing Group
Numerical Investigation of Heat Transfer in 4-Pass Fire-Tube Boiler
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140205.12
In this paper, the heat transfer in 4-pass 500HP fire-tube steam boiler is numerically investigated. A calculation program is carried out in order to simulate the heat transfer characteristics between the hot gases and the boiler tube internal walls. Especially, the heat flux densities and the corresponding wall temperatures for different operating conditions. On these surfaces, an energy balance is established taking into account the radiation and the convection heat transfer. The model validation consists in comparing the predicted outlet gas temperature with the operating data of the PFTA 500HP fire-tube boiler for several steady-state conditions. The comparison shows that the calculation results are in good agreement with the boiler operating data. Furthermore, a sensitivity study has been carried out to investigate the operating pressure effect on the boiler thermal performances.
In this paper, the heat transfer in 4-pass 500HP fire-tube steam boiler is numerically investigated. A calculation program is carried out in order to simulate the heat transfer characteristics between the hot gases and the boiler tube internal walls. Especially, the heat flux densities and the corresponding wall temperatures for different operating conditions. On these surfaces, an energy balance is established taking into account the radiation and the convection heat transfer. The model validation consists in comparing the predicted outlet gas temperature with the operating data of the PFTA 500HP fire-tube boiler for several steady-state conditions. The comparison shows that the calculation results are in good agreement with the boiler operating data. Furthermore, a sensitivity study has been carried out to investigate the operating pressure effect on the boiler thermal performances.
Numerical Investigation of Heat Transfer in 4-Pass Fire-Tube Boiler
doi:10.11648/j.ajche.20140205.12
American Journal of Chemical Engineering
2014-09-23
© Science Publishing Group
Ahmed Rahmani
Soumia Trabelsi
Numerical Investigation of Heat Transfer in 4-Pass Fire-Tube Boiler
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70
70
2014-09-23
2014-09-23
10.11648/j.ajche.20140205.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140205.12
© Science Publishing Group
Bauxite Enrichment by Microwave-Magnetising Roasting Using Sawdust as Reducing Agent
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140205.11
As high grade bauxite is getting depleted in several parts of the world, bauxite with high iron content is becoming increasingly important, and this trend has called for studies into the reduction of iron in bauxite. This study investigated the use of microwave energy in the magnetising roasting of high-iron bauxite using sawdust as reducing agent. Mineralogical studies revealed gibbsite and goethite as the main constituents of bauxite. The sawdust utilised had a fixed carbon content of 7.2% and ash, 1.7%. Microwave heating responses of bauxite and sawdust were determined as a function of mass and time, and both materials proved to be active microwave absorbers as they heated rapidly. Magnetising roasting of the bauxite sample was conducted with 20-40% sawdust at temperatures between 870oC and 880oC. After magnetic separation, the major phase in the magnetic fraction was magnetite, while gibbsite and boehmite were the major phases in the non-magnetic fraction. The alumina content of the non-magnetic fraction increased to 87.5% from an as-received sample grade of 53.6%. The use of sawdust in this manner satisfies a dual role of environmental clean-up and bauxite enrichment.
As high grade bauxite is getting depleted in several parts of the world, bauxite with high iron content is becoming increasingly important, and this trend has called for studies into the reduction of iron in bauxite. This study investigated the use of microwave energy in the magnetising roasting of high-iron bauxite using sawdust as reducing agent. Mineralogical studies revealed gibbsite and goethite as the main constituents of bauxite. The sawdust utilised had a fixed carbon content of 7.2% and ash, 1.7%. Microwave heating responses of bauxite and sawdust were determined as a function of mass and time, and both materials proved to be active microwave absorbers as they heated rapidly. Magnetising roasting of the bauxite sample was conducted with 20-40% sawdust at temperatures between 870oC and 880oC. After magnetic separation, the major phase in the magnetic fraction was magnetite, while gibbsite and boehmite were the major phases in the non-magnetic fraction. The alumina content of the non-magnetic fraction increased to 87.5% from an as-received sample grade of 53.6%. The use of sawdust in this manner satisfies a dual role of environmental clean-up and bauxite enrichment.
Bauxite Enrichment by Microwave-Magnetising Roasting Using Sawdust as Reducing Agent
doi:10.11648/j.ajche.20140205.11
American Journal of Chemical Engineering
2014-09-01
© Science Publishing Group
Grace Ofori-Sarpong
Charles Ebenezer Abbey
Richmond Komla Asamoah
Richard Kwasi Amankwah
Bauxite Enrichment by Microwave-Magnetising Roasting Using Sawdust as Reducing Agent
2
5
64
64
2014-09-01
2014-09-01
10.11648/j.ajche.20140205.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140205.11
© Science Publishing Group
Predicting Reactants’ Hydrodynamic Behavior Inside Non-Porous Catalytic Reactors
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140206.11
Gaseous reactants usually have complex behaviors ranging from unsteady flow patterns to oscillations due to the differences in various physical and chemical properties. Such behaviors hinder the complete understanding coupled between transport processes and chemical kinetics. Systems within which chemical reactions are coupled with diffusion and convective transport have chemical engineering applications. The aim of the present work is to simulate the steady state behavior of a reaction-diffusion-convection system using the finite element method for ammonia decomposition. The overall model used consists of the flow and mass transport modules which are described by the continuity, Stokes equations and the convective dispersion equation respectively. Concentration profile, velocity and pressure fields presented are for a first order reaction for ammonia decomposition inside tubular non-porous catalytic reactors. Two different types of reactors are considered, the first one represents a fuel cell and the second is for a catalytic wall reactor.
Gaseous reactants usually have complex behaviors ranging from unsteady flow patterns to oscillations due to the differences in various physical and chemical properties. Such behaviors hinder the complete understanding coupled between transport processes and chemical kinetics. Systems within which chemical reactions are coupled with diffusion and convective transport have chemical engineering applications. The aim of the present work is to simulate the steady state behavior of a reaction-diffusion-convection system using the finite element method for ammonia decomposition. The overall model used consists of the flow and mass transport modules which are described by the continuity, Stokes equations and the convective dispersion equation respectively. Concentration profile, velocity and pressure fields presented are for a first order reaction for ammonia decomposition inside tubular non-porous catalytic reactors. Two different types of reactors are considered, the first one represents a fuel cell and the second is for a catalytic wall reactor.
Predicting Reactants’ Hydrodynamic Behavior Inside Non-Porous Catalytic Reactors
doi:10.11648/j.ajche.20140206.11
American Journal of Chemical Engineering
2014-10-18
© Science Publishing Group
Ihab Shigidi
Predicting Reactants’ Hydrodynamic Behavior Inside Non-Porous Catalytic Reactors
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75
75
2014-10-18
2014-10-18
10.11648/j.ajche.20140206.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140206.11
© Science Publishing Group
Densities and Partial Molar Volumes of Dodecyltrimethylammonium Bromide in Binary Systems (Methanol+Water) at T=(298.15 to 323.15) K
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140206.12
The densities of dodecyltrimethylammonium bromide in pure water and in methanol + water mixed solvent media containing (0.10, 0.20, 0.30, and 0.40) volume fractions of methanol were measured at (298.15, 308.15, 318.15, and 323.15) K. The concentrations are varied from (0.4 10-1 to 1.2 10-1) mol kg-1. The results showed almost increase on the densities with increasing surfactant concentration. Also, the densities are found to decrease with increasing temperature over the entire concentration range investigated in a given mixed solvent medium and these values are found to decrease with increasing methanol content in the solvent composition. The effects of concentration, solvent composition and temperature on the partial molar volumes are discussed.
The densities of dodecyltrimethylammonium bromide in pure water and in methanol + water mixed solvent media containing (0.10, 0.20, 0.30, and 0.40) volume fractions of methanol were measured at (298.15, 308.15, 318.15, and 323.15) K. The concentrations are varied from (0.4 10-1 to 1.2 10-1) mol kg-1. The results showed almost increase on the densities with increasing surfactant concentration. Also, the densities are found to decrease with increasing temperature over the entire concentration range investigated in a given mixed solvent medium and these values are found to decrease with increasing methanol content in the solvent composition. The effects of concentration, solvent composition and temperature on the partial molar volumes are discussed.
Densities and Partial Molar Volumes of Dodecyltrimethylammonium Bromide in Binary Systems (Methanol+Water) at T=(298.15 to 323.15) K
doi:10.11648/j.ajche.20140206.12
American Journal of Chemical Engineering
2014-10-29
© Science Publishing Group
Sujit Kumar Shah
Ajaya Bhattarai
Sujeet Kumar Chatterjee
Densities and Partial Molar Volumes of Dodecyltrimethylammonium Bromide in Binary Systems (Methanol+Water) at T=(298.15 to 323.15) K
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85
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2014-10-29
2014-10-29
10.11648/j.ajche.20140206.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140206.12
© Science Publishing Group
Removal of Copper and Fluoride from Wastewater by the Coupling of Electrocoagulation, Fluidized Bed and Micro-Electrolysis (EC/FB/ME) Process
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140206.13
Copper and fluoride ions were removed from wastewater by the coupling of electrocoagulation, fluidized bed and micro-electrolysis (EC/FB/ME) process. The results indicate that the use of aluminum electrode for simultaneous removal of copper and fluoride ions is better than iron electrode. By the orthogonal experiments study of the main factors influencing the efficiency of the treatment process, the best control parameters of this process were achieved in four aluminum electrodes, an initial pH of 5.0, a hydraulic retention time of 30 minutes, an applied voltage of 5V, a mass of iron-carbon (Fe/C) of 45g and the particle diameter of Fe/C of 20-27 mesh. With these conditions and the initial concentration of ions of 50mg/L, the residual concentration of copper and fluoride are 0.205 mg/L and 2.936 mg/L, respectively. The EC/FB/ME process is suitable for treatment of wastewater that fluoride concentration is less than 50 mg/L and copper concentration is less than 200 mg/L. This process was successfully applied to the treatment of a smelting wastewater sample.
Copper and fluoride ions were removed from wastewater by the coupling of electrocoagulation, fluidized bed and micro-electrolysis (EC/FB/ME) process. The results indicate that the use of aluminum electrode for simultaneous removal of copper and fluoride ions is better than iron electrode. By the orthogonal experiments study of the main factors influencing the efficiency of the treatment process, the best control parameters of this process were achieved in four aluminum electrodes, an initial pH of 5.0, a hydraulic retention time of 30 minutes, an applied voltage of 5V, a mass of iron-carbon (Fe/C) of 45g and the particle diameter of Fe/C of 20-27 mesh. With these conditions and the initial concentration of ions of 50mg/L, the residual concentration of copper and fluoride are 0.205 mg/L and 2.936 mg/L, respectively. The EC/FB/ME process is suitable for treatment of wastewater that fluoride concentration is less than 50 mg/L and copper concentration is less than 200 mg/L. This process was successfully applied to the treatment of a smelting wastewater sample.
Removal of Copper and Fluoride from Wastewater by the Coupling of Electrocoagulation, Fluidized Bed and Micro-Electrolysis (EC/FB/ME) Process
doi:10.11648/j.ajche.20140206.13
American Journal of Chemical Engineering
2014-11-14
© Science Publishing Group
Vo Anh Khue
Li Tian Guo
Xu Xiao Jun
Yue Xiu Lin
Peng Rui Hao
Removal of Copper and Fluoride from Wastewater by the Coupling of Electrocoagulation, Fluidized Bed and Micro-Electrolysis (EC/FB/ME) Process
2
6
91
91
2014-11-14
2014-11-14
10.11648/j.ajche.20140206.13
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140206.13
© Science Publishing Group
Use of Agriculture-Based Waste for Basic Dye Sorption from Aqueous Solution: Kinetics and Isotherm Studies
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140206.14
Low-cost bare palm branches were prepared as a sorbent for methylene blue dye from aqueous solution. The effect of reaction parameters such as sorbent dose and its particle size, initial dye concentration and the medium temperature were investigated using a batch sorption technique. Additionally, the maximum saturated monolayer sorption capacity of bare palm branches for methylene blue dye was investigated. The isotherm data was well-described by the Freundlich equation. Based on the adsorption capacity, it was shown that the use of bare palm branches was a promising low-cost agriculture waste material for the adsorption of dyes from aqueous solutions. Kinetic parameters of adsorption such as the rate constant and the intra-particle diffusion rate constant were determined. The principal conclusions of the study were that the reaction follows the pseudo-second order reaction kinetics.
Low-cost bare palm branches were prepared as a sorbent for methylene blue dye from aqueous solution. The effect of reaction parameters such as sorbent dose and its particle size, initial dye concentration and the medium temperature were investigated using a batch sorption technique. Additionally, the maximum saturated monolayer sorption capacity of bare palm branches for methylene blue dye was investigated. The isotherm data was well-described by the Freundlich equation. Based on the adsorption capacity, it was shown that the use of bare palm branches was a promising low-cost agriculture waste material for the adsorption of dyes from aqueous solutions. Kinetic parameters of adsorption such as the rate constant and the intra-particle diffusion rate constant were determined. The principal conclusions of the study were that the reaction follows the pseudo-second order reaction kinetics.
Use of Agriculture-Based Waste for Basic Dye Sorption from Aqueous Solution: Kinetics and Isotherm Studies
doi:10.11648/j.ajche.20140206.14
American Journal of Chemical Engineering
2014-12-23
© Science Publishing Group
Eman A. Ashour
Maha A. Tony
Patrick J. Purcell
Use of Agriculture-Based Waste for Basic Dye Sorption from Aqueous Solution: Kinetics and Isotherm Studies
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98
98
2014-12-23
2014-12-23
10.11648/j.ajche.20140206.14
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20140206.14
© Science Publishing Group
Effect of Mesoporous Catalysts on the Mainstream Tobacco Smoke of 3R4F and 1R5F Reference Cigarettes
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20150301.11
The effect of three synthesised mesoporous catalysts (a SBA-15 and two MCM-41) on the smoke of two reference tobaccos (1R5F and 3R4F) has been studied. Mixtures of the catalysts and each tobacco were smoked under the ISO 3388 standard conditions. The gaseous compounds and the particulate matter condensed in the filter tip (TPM-F) and in a trap located downstream (TPM-T) from the mainstream smoke were analysed separately. The results obtained show that these catalysts directly mixed with tobacco are capable of reducing the yield of most of the compounds studied in the mainstream tobacco smoke. SBA-15 is a better additive for reducing the amount of the compounds analysed in 1R5F and 3R4F tobaccos, both in the liquid fraction (TPM-F and TPM-T) and in the gas fraction. The effect of the studied catalysts is higher on the full-flavour cigarette than on the ultra-low one. As an example, the reductions observed for CO and nicotine in TPM-T from 3R4F as a consequence of the SBA-15 addition were 46% and 77%, respectively. Thus, although the three checked materials are able to provide noticeable reductions, the best is the one having the higher size of pores (SBA-15).
The effect of three synthesised mesoporous catalysts (a SBA-15 and two MCM-41) on the smoke of two reference tobaccos (1R5F and 3R4F) has been studied. Mixtures of the catalysts and each tobacco were smoked under the ISO 3388 standard conditions. The gaseous compounds and the particulate matter condensed in the filter tip (TPM-F) and in a trap located downstream (TPM-T) from the mainstream smoke were analysed separately. The results obtained show that these catalysts directly mixed with tobacco are capable of reducing the yield of most of the compounds studied in the mainstream tobacco smoke. SBA-15 is a better additive for reducing the amount of the compounds analysed in 1R5F and 3R4F tobaccos, both in the liquid fraction (TPM-F and TPM-T) and in the gas fraction. The effect of the studied catalysts is higher on the full-flavour cigarette than on the ultra-low one. As an example, the reductions observed for CO and nicotine in TPM-T from 3R4F as a consequence of the SBA-15 addition were 46% and 77%, respectively. Thus, although the three checked materials are able to provide noticeable reductions, the best is the one having the higher size of pores (SBA-15).
Effect of Mesoporous Catalysts on the Mainstream Tobacco Smoke of 3R4F and 1R5F Reference Cigarettes
doi:10.11648/j.ajche.20150301.11
American Journal of Chemical Engineering
2015-03-08
© Science Publishing Group
Antonio Marcilla Gomis
Amparo Gómez Siurana
Deseada Berenguer Muñoz
Isabel Martínez Castellanos
Maribel Beltrán
Effect of Mesoporous Catalysts on the Mainstream Tobacco Smoke of 3R4F and 1R5F Reference Cigarettes
3
1
18
18
2015-03-08
2015-03-08
10.11648/j.ajche.20150301.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20150301.11
© Science Publishing Group
Simulation of the Solubility of SO2 on Water Using CFD Modeling Airlift Reactor
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20150301.12
Nowadays, petroleum and power plants emissions are increasingly recognized as a serious, worldwide public concern. In recent years, there has been an increasing interest to find solutions to decrease SO2 and the sulfur dioxide emissions from petroleum and electricity facilities. So far, several attempts have been made to figure out methods, procedures or techniques to lessen the emissions of SO2 which requires high cost to develop these techniques. However, the current research provides a solution to this issue through simulation, which allows new ways to test and diagnose these methods, procedures with low cost and danger. Nevertheless, solubility of SO2 in water may consider as conventional approach while sulfur dioxide of SO2 is a soluble gas in water, which can be oxidized through cloud and fog by producing sulfuric acid. Finally, this paper offers a new way to test SO2 solubility through using CFD modeling Airlift reactors.
Nowadays, petroleum and power plants emissions are increasingly recognized as a serious, worldwide public concern. In recent years, there has been an increasing interest to find solutions to decrease SO2 and the sulfur dioxide emissions from petroleum and electricity facilities. So far, several attempts have been made to figure out methods, procedures or techniques to lessen the emissions of SO2 which requires high cost to develop these techniques. However, the current research provides a solution to this issue through simulation, which allows new ways to test and diagnose these methods, procedures with low cost and danger. Nevertheless, solubility of SO2 in water may consider as conventional approach while sulfur dioxide of SO2 is a soluble gas in water, which can be oxidized through cloud and fog by producing sulfuric acid. Finally, this paper offers a new way to test SO2 solubility through using CFD modeling Airlift reactors.
Simulation of the Solubility of SO2 on Water Using CFD Modeling Airlift Reactor
doi:10.11648/j.ajche.20150301.12
American Journal of Chemical Engineering
2015-04-15
© Science Publishing Group
Rana R. AL-Hussari
Ahad D. AL-Fatlawy
Mohammed H. Al-Aqad
Simulation of the Solubility of SO2 on Water Using CFD Modeling Airlift Reactor
3
1
24
24
2015-04-15
2015-04-15
10.11648/j.ajche.20150301.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20150301.12
© Science Publishing Group
Life Cycle Assessment of a Biodiesel Production Unit
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20150302.11
Carbon dioxide is one of the main compounds pointed as a cause for climate changes, mainly due to the accelerated use of fossil fuels. In order to measure the consumption of the resources that generate carbon dioxide and verify these compounds emissions, quantitative studies aren’t sufficient, but it is needed a proportion relation with the environmental impact. Hence, Life cycle analysis (LCA) studies are used to establish parameters to this relation, orientating which is the best way to be followed and also estimating, as close as possible to the reality, the degree of impacts that can be caused. In this paper a biodiesel plant LCA study is realized, using the model described in ISO 14040 groups. Biodiesel is an alternative renewable fuel to the common diesel. Despite been considered a “clean” fuel, its fabrication process involves environmental impacts. This paper quantifies those impacts, from a theoretical biodiesel plant data, and compares them with those generated on the biodiesel production. The conclusions achieved are that the carbon dioxide generated is greater than the consumed during the entire biodiesel life cycle. However, the biodiesel production generates about 174 times less carbon dioxide than the refining to obtain diesel. Besides, both diesel and biodiesel are responsible for Nitrogen oxide emissions (qualitatively) and it is possible estimate that the environmental impact generated by those emissions is similar between these fuels.
Carbon dioxide is one of the main compounds pointed as a cause for climate changes, mainly due to the accelerated use of fossil fuels. In order to measure the consumption of the resources that generate carbon dioxide and verify these compounds emissions, quantitative studies aren’t sufficient, but it is needed a proportion relation with the environmental impact. Hence, Life cycle analysis (LCA) studies are used to establish parameters to this relation, orientating which is the best way to be followed and also estimating, as close as possible to the reality, the degree of impacts that can be caused. In this paper a biodiesel plant LCA study is realized, using the model described in ISO 14040 groups. Biodiesel is an alternative renewable fuel to the common diesel. Despite been considered a “clean” fuel, its fabrication process involves environmental impacts. This paper quantifies those impacts, from a theoretical biodiesel plant data, and compares them with those generated on the biodiesel production. The conclusions achieved are that the carbon dioxide generated is greater than the consumed during the entire biodiesel life cycle. However, the biodiesel production generates about 174 times less carbon dioxide than the refining to obtain diesel. Besides, both diesel and biodiesel are responsible for Nitrogen oxide emissions (qualitatively) and it is possible estimate that the environmental impact generated by those emissions is similar between these fuels.
Life Cycle Assessment of a Biodiesel Production Unit
doi:10.11648/j.ajche.20150302.11
American Journal of Chemical Engineering
2015-04-15
© Science Publishing Group
Priscilla Sieira
Erick B. F. Galante
Alvaro J. Boareto Mendes
Assed Haddad
Life Cycle Assessment of a Biodiesel Production Unit
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29
29
2015-04-15
2015-04-15
10.11648/j.ajche.20150302.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20150302.11
© Science Publishing Group
Effect of Starch on the Mechanical and Rheological Properties of Polypropylene
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.11
Blends of starch (tapioca) and polypropylene were prepared in various wt/wt concentrations ranging from 100% polypropylene resins to 5:95, 10:90, 20:80, 30:70, 40:60, and 50:50 wt% starch to wt% polypropylene blends. Then the rheological and mechanical properties of the resulting blends were determined using Plastometer and Universal Testing Machine respectively. Tensile strength, percentage elongation, flexural modulus, Izod impact, vicat softening temperature and melt flow index tests were carried out according to American standard for testing and materials procedure. The melt flow index was found to decrease linearly with increasing starch concentrations up to 30 wt% starch to wt% plastic, beyond which no flow was observed. The presence of starch in polypropylene was found to have positive effect on some of the mechanical properties like flexural modulus and Izod impact strength, whereas a negative impact was obtained on the tensile strength and percentage elongation. It was observed that higher starch loadings above 30% reduced the mechanical properties while lower starch loadings below 30% improved some mechanical properties. In addition, higher starch loadings above 30% does not favor the melt flow index and the Izod impact strength since there was no flow due to lower vicat softening temperature. Thus, with the aid of controlled incorporation of the starch additive, several properties of the modified polypropylene specimen could be enhanced.
Blends of starch (tapioca) and polypropylene were prepared in various wt/wt concentrations ranging from 100% polypropylene resins to 5:95, 10:90, 20:80, 30:70, 40:60, and 50:50 wt% starch to wt% polypropylene blends. Then the rheological and mechanical properties of the resulting blends were determined using Plastometer and Universal Testing Machine respectively. Tensile strength, percentage elongation, flexural modulus, Izod impact, vicat softening temperature and melt flow index tests were carried out according to American standard for testing and materials procedure. The melt flow index was found to decrease linearly with increasing starch concentrations up to 30 wt% starch to wt% plastic, beyond which no flow was observed. The presence of starch in polypropylene was found to have positive effect on some of the mechanical properties like flexural modulus and Izod impact strength, whereas a negative impact was obtained on the tensile strength and percentage elongation. It was observed that higher starch loadings above 30% reduced the mechanical properties while lower starch loadings below 30% improved some mechanical properties. In addition, higher starch loadings above 30% does not favor the melt flow index and the Izod impact strength since there was no flow due to lower vicat softening temperature. Thus, with the aid of controlled incorporation of the starch additive, several properties of the modified polypropylene specimen could be enhanced.
Effect of Starch on the Mechanical and Rheological Properties of Polypropylene
doi:10.11648/j.ajche.s.2015030201.11
American Journal of Chemical Engineering
2015-01-14
© Science Publishing Group
M. K. Oduola
P. O. Akpeji
Effect of Starch on the Mechanical and Rheological Properties of Polypropylene
3
2
8
8
2015-01-14
2015-01-14
10.11648/j.ajche.s.2015030201.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.11
© Science Publishing Group
Development of Model Equations for Predicting Gasoline Blending Properties
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.12
Gasoline blending is of pertinent importance in refinery operations owing to the fact that gasoline gives about 60 - 70 % of the refinery profit. The blending process is essential to obtain gasoline in the demanded quantities and ensure property specifications are met. Two model equations, multivariable nonlinear and multivariable exponential are proposed in this study which are useful in predicting three significant properties of a motor gasoline: research octane number, reid vapour pressure and specific gravity. Gasoline blend data obtained from four different streams: straight run gasoline, straight run naphtha, reformate and fluidized catalytically cracked gasoline have been subjected to multivariate regression analysis with the aid of a statistical software to ascertain the fitness of the proposed equations in predicting the research octane number, reid vapor pressure and the specific gravity of the resulting premium motor spirit. The results of the regression analysis showed that the nonlinear multivariable models proposed gave a good fit as evidenced by the value of the coefficient of determination R2 = 0.988 & 0.994 for the research octane number, 0.853 & 0.883 for the reid vapor pressure and 0.988 for specific gravity. In conclusion, the proposed model equations were fit to the data, found to be adequate, and therefore could be used for prediction of the blend gasoline properties.
Gasoline blending is of pertinent importance in refinery operations owing to the fact that gasoline gives about 60 - 70 % of the refinery profit. The blending process is essential to obtain gasoline in the demanded quantities and ensure property specifications are met. Two model equations, multivariable nonlinear and multivariable exponential are proposed in this study which are useful in predicting three significant properties of a motor gasoline: research octane number, reid vapour pressure and specific gravity. Gasoline blend data obtained from four different streams: straight run gasoline, straight run naphtha, reformate and fluidized catalytically cracked gasoline have been subjected to multivariate regression analysis with the aid of a statistical software to ascertain the fitness of the proposed equations in predicting the research octane number, reid vapor pressure and the specific gravity of the resulting premium motor spirit. The results of the regression analysis showed that the nonlinear multivariable models proposed gave a good fit as evidenced by the value of the coefficient of determination R2 = 0.988 & 0.994 for the research octane number, 0.853 & 0.883 for the reid vapor pressure and 0.988 for specific gravity. In conclusion, the proposed model equations were fit to the data, found to be adequate, and therefore could be used for prediction of the blend gasoline properties.
Development of Model Equations for Predicting Gasoline Blending Properties
doi:10.11648/j.ajche.s.2015030201.12
American Journal of Chemical Engineering
2015-01-19
© Science Publishing Group
M. K. Oduola
A. I. Iyaomolere
Development of Model Equations for Predicting Gasoline Blending Properties
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17
17
2015-01-19
2015-01-19
10.11648/j.ajche.s.2015030201.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.12
© Science Publishing Group
Aligning the Nigerian Petrochemical Industry to Oil and Gas Industry Needs
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.13
Nigeria is Africa’s largest producer of crude oil and the sixth largest exporter of oil within the OPEC bloc. However, virtually all chemical and petrochemical products used in the Nigerian oil and gas industry are currently imported. There is therefore the need for the Nigerian petrochemical industry to reposition itself to take advantage of these increasing market opportunities. This paper examines the strategic fit of the petrochemical industry within the value chain of the oil and gas industry, using critical petrochemical-based products as examples.
Nigeria is Africa’s largest producer of crude oil and the sixth largest exporter of oil within the OPEC bloc. However, virtually all chemical and petrochemical products used in the Nigerian oil and gas industry are currently imported. There is therefore the need for the Nigerian petrochemical industry to reposition itself to take advantage of these increasing market opportunities. This paper examines the strategic fit of the petrochemical industry within the value chain of the oil and gas industry, using critical petrochemical-based products as examples.
Aligning the Nigerian Petrochemical Industry to Oil and Gas Industry Needs
doi:10.11648/j.ajche.s.2015030201.13
American Journal of Chemical Engineering
2015-05-09
© Science Publishing Group
Ajee Mamman
Aligning the Nigerian Petrochemical Industry to Oil and Gas Industry Needs
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2015-05-09
2015-05-09
10.11648/j.ajche.s.2015030201.13
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.13
© Science Publishing Group
Technical Analysis of the Natural Gas to Hydrocarbon Liquid Process
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.14
The technical analysis carried out in this paper is aimed at dealing with element incorporation, structure generation and optimization of the gas-to-liquid (GTL) process. The GTL model developed did not include the desulphurization unit as well as the product upgrading unit. A detailed description of the sequential steps for analyzing the process is as follows: firstly, a base-case process is designed with parameters and operating conditions obtained from literature. Secondly, this flowsheet is simulated with computer-aided simulation package ASPEN Hysys V8.4 to evaluate the specific characteristics of the main equipment and streams entering and leaving units. Thirdly, the simulated base case was analyzed in terms of Thermal Efficiency (TE), Carbon Efficiency (CE) and product flow to upgrading. This process was carried out using the optimizer tool for steady-state modelling to account for multiple variables in the Hysys simulation with the aid of case studies to maximize a given objective function. This resulted in a CE of 82.41%, TE of 65.93% and a production of 19940 bbl/d of syncrude.
The technical analysis carried out in this paper is aimed at dealing with element incorporation, structure generation and optimization of the gas-to-liquid (GTL) process. The GTL model developed did not include the desulphurization unit as well as the product upgrading unit. A detailed description of the sequential steps for analyzing the process is as follows: firstly, a base-case process is designed with parameters and operating conditions obtained from literature. Secondly, this flowsheet is simulated with computer-aided simulation package ASPEN Hysys V8.4 to evaluate the specific characteristics of the main equipment and streams entering and leaving units. Thirdly, the simulated base case was analyzed in terms of Thermal Efficiency (TE), Carbon Efficiency (CE) and product flow to upgrading. This process was carried out using the optimizer tool for steady-state modelling to account for multiple variables in the Hysys simulation with the aid of case studies to maximize a given objective function. This resulted in a CE of 82.41%, TE of 65.93% and a production of 19940 bbl/d of syncrude.
Technical Analysis of the Natural Gas to Hydrocarbon Liquid Process
doi:10.11648/j.ajche.s.2015030201.14
American Journal of Chemical Engineering
2015-05-09
© Science Publishing Group
I. J. Otaraku
O. A. Vincent
Technical Analysis of the Natural Gas to Hydrocarbon Liquid Process
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2015-05-09
2015-05-09
10.11648/j.ajche.s.2015030201.14
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.14
© Science Publishing Group
Simulation of Loading Capacity of MDEA and DEA for Amine-Based CO2 Removal Using Hysys
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.15
Besides meeting international stringent LNG product specification, this work will address the problem of off-spec product, high operational cost of acid gas (CO2) removal and pollution-free product, which is currently a huge global challenge. This work studied other ways by which amine unit can best be optimized to produce LNG gas with low CO2-content and high cost of acid gas removal. MDEA instead of DEA solvent-absorption method was chosen for the optimization using HYSYS 3.1 process simulator to predict the CO2 removal through the establishment of process operating conditions. A base case of amine-based CO2 removal process was used to create a steady-state and dynamic simulation using HYSYS 3.1 simulator. The differences between the values of acid gas loading capacity and CO2 content of the existing DEA operational value and HYSYS simulations were 0.00005 and 4.98 respectively. This established the advantage and accuracy of the HYSYS simulator and the developed models. The simulation results showed that the proposed MDEA had higher CO2 removal capacity of 89% to 55.02% for DEA and lower CO2 content of 0.0012 mole of CO2 in sweet gas to 0.014 mole of CO2 in DEA. MDEA had higher solvent recovery of 83% to 60% recovery for DEA. The pump size required to recycle MDEA with molar flow rate of 1877 Kg mol/hr. was smaller and less expensive than that required for DEA at 2371 Kg mol./hr. resulting in lower production cost.
Besides meeting international stringent LNG product specification, this work will address the problem of off-spec product, high operational cost of acid gas (CO2) removal and pollution-free product, which is currently a huge global challenge. This work studied other ways by which amine unit can best be optimized to produce LNG gas with low CO2-content and high cost of acid gas removal. MDEA instead of DEA solvent-absorption method was chosen for the optimization using HYSYS 3.1 process simulator to predict the CO2 removal through the establishment of process operating conditions. A base case of amine-based CO2 removal process was used to create a steady-state and dynamic simulation using HYSYS 3.1 simulator. The differences between the values of acid gas loading capacity and CO2 content of the existing DEA operational value and HYSYS simulations were 0.00005 and 4.98 respectively. This established the advantage and accuracy of the HYSYS simulator and the developed models. The simulation results showed that the proposed MDEA had higher CO2 removal capacity of 89% to 55.02% for DEA and lower CO2 content of 0.0012 mole of CO2 in sweet gas to 0.014 mole of CO2 in DEA. MDEA had higher solvent recovery of 83% to 60% recovery for DEA. The pump size required to recycle MDEA with molar flow rate of 1877 Kg mol/hr. was smaller and less expensive than that required for DEA at 2371 Kg mol./hr. resulting in lower production cost.
Simulation of Loading Capacity of MDEA and DEA for Amine-Based CO2 Removal Using Hysys
doi:10.11648/j.ajche.s.2015030201.15
American Journal of Chemical Engineering
2015-05-09
© Science Publishing Group
I. J. Otaraku
F. O. Esemuze
Simulation of Loading Capacity of MDEA and DEA for Amine-Based CO2 Removal Using Hysys
3
2
46
46
2015-05-09
2015-05-09
10.11648/j.ajche.s.2015030201.15
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.15
© Science Publishing Group
Hydrogen Pinch Analysis of a Petroleum Refinery as an Energy Management Strategy
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.16
The glaring need for energy management in a petroleum refining industry is as a result of significant refinery energy costs, typically 40-50% of operating costs. Consequently, energy auditing is frequently carried out to identify energy management opportunities for higher profitability. Hydrogen management in a refining plant by means of the hydrogen pinch analysis approach aimed at identifying the optimum hydrogen network has been recognized as an effective way of optimizing the processes. The numerous benefits of hydrogen management include maximum processing revenue as a result of reduced hydrogen system operating costs and production benefits, minimum capital investment, reduced carbon dioxide emissions, and more importantly, up to 20% cost savings from energy efficiency improvements. Hydrogen pinch technology has been employed in this study to discover optimum hydrogen distribution systems which can be a potential energy management opportunity in a refining industry. The goal was to identify shortcomings in the hydrogen distribution of the system so as to improve the energy utilization of the plant. Analysis of the case study resulted in identification of optimum hydrogen target for the system. Achieving the target will reduce the power consumption of the catalytic reforming unit by 10.8% and also help to conserve hydrogen use by more than 20%. Implementation of suggestions for efficient utilization of energy made will increase the profit as well as the operating costs. However, there will be annual increase in marginal revenue as the profit is considerably greater than the operating costs. The payback period and return on investment (ROI) of these suggestions are less than 3yrs and 28% - 44% (depending on the option adopted) respectively. Another significant advantage of the project is that it will reduce the gas flaring and helps prepare the refinery for future environmental challenges.
The glaring need for energy management in a petroleum refining industry is as a result of significant refinery energy costs, typically 40-50% of operating costs. Consequently, energy auditing is frequently carried out to identify energy management opportunities for higher profitability. Hydrogen management in a refining plant by means of the hydrogen pinch analysis approach aimed at identifying the optimum hydrogen network has been recognized as an effective way of optimizing the processes. The numerous benefits of hydrogen management include maximum processing revenue as a result of reduced hydrogen system operating costs and production benefits, minimum capital investment, reduced carbon dioxide emissions, and more importantly, up to 20% cost savings from energy efficiency improvements. Hydrogen pinch technology has been employed in this study to discover optimum hydrogen distribution systems which can be a potential energy management opportunity in a refining industry. The goal was to identify shortcomings in the hydrogen distribution of the system so as to improve the energy utilization of the plant. Analysis of the case study resulted in identification of optimum hydrogen target for the system. Achieving the target will reduce the power consumption of the catalytic reforming unit by 10.8% and also help to conserve hydrogen use by more than 20%. Implementation of suggestions for efficient utilization of energy made will increase the profit as well as the operating costs. However, there will be annual increase in marginal revenue as the profit is considerably greater than the operating costs. The payback period and return on investment (ROI) of these suggestions are less than 3yrs and 28% - 44% (depending on the option adopted) respectively. Another significant advantage of the project is that it will reduce the gas flaring and helps prepare the refinery for future environmental challenges.
Hydrogen Pinch Analysis of a Petroleum Refinery as an Energy Management Strategy
doi:10.11648/j.ajche.s.2015030201.16
American Journal of Chemical Engineering
2015-05-09
© Science Publishing Group
M. K. Oduola
T. B. Oguntola
Hydrogen Pinch Analysis of a Petroleum Refinery as an Energy Management Strategy
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54
54
2015-05-09
2015-05-09
10.11648/j.ajche.s.2015030201.16
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.16
© Science Publishing Group
Comparative Economic Investigation Options for Liquefied Petroleum Gas Production from Natural Gas Liquids
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.17
There is new trend in the value of oil and gas in the world, with the value of Liquefied Petroleum Gas (LPG) soaring higher. It is due to its uses as a potential fuel in the several parts of the world, its demand in the petrochemical industries for plastics and automotive composites productions, and other uses. These results in steadily increases in price. There is also increase in volume of feed gas, which demands efficient LPG processing and recovery technology. This paper mainly focuses on comparative economic investigation options for Liquefied Petroleum Gas plant, which processes feed from natural gas wells and dehydrating units to produce Liquefied Petroleum Gas along with natural gasoline having a higher value as separate product. Recovery of LPG is possible but raises both the initial cost of plant and operational cost considerably. The value of LPG recovered should be high enough to widen the operating margins between the processing costs and the market price for which the recovered liquids can be sold. Therefore, the most economic means of extracting this product must be used. This was done using two alternatives; the Conventional Fractionation process and Single column overhead recycle process (SCORE). Both alternatives were simulated with Hysys and are analyzed based on product recovery level, energy required and fixed capital cost. There are two feeds to the plant, one from the natural gas wells and the other from dehydrating units of natural gas processing plants with a total flow rate of 6.99 MMSCFD. Analysis of result from modeling shows that Single column overhead recycle process has a total product recovery of 97.2 % while Conventional fractionation process has a total recovery of 88.5 %, the require energy margin between the alternatives is about 38.9 % in favor of conventional process and the fixed capital cost is in the favor of Single column process. Sensitive to choosing the most economic option of LPG recovery between the conventional process and SCORE process is the recovery level of LPG from each of the options, total energy required and the cost of the equipment. From the analysis, it shows that, it is more economical to use the Single column overhead recycle process, as compared to conventional fractionation process.
There is new trend in the value of oil and gas in the world, with the value of Liquefied Petroleum Gas (LPG) soaring higher. It is due to its uses as a potential fuel in the several parts of the world, its demand in the petrochemical industries for plastics and automotive composites productions, and other uses. These results in steadily increases in price. There is also increase in volume of feed gas, which demands efficient LPG processing and recovery technology. This paper mainly focuses on comparative economic investigation options for Liquefied Petroleum Gas plant, which processes feed from natural gas wells and dehydrating units to produce Liquefied Petroleum Gas along with natural gasoline having a higher value as separate product. Recovery of LPG is possible but raises both the initial cost of plant and operational cost considerably. The value of LPG recovered should be high enough to widen the operating margins between the processing costs and the market price for which the recovered liquids can be sold. Therefore, the most economic means of extracting this product must be used. This was done using two alternatives; the Conventional Fractionation process and Single column overhead recycle process (SCORE). Both alternatives were simulated with Hysys and are analyzed based on product recovery level, energy required and fixed capital cost. There are two feeds to the plant, one from the natural gas wells and the other from dehydrating units of natural gas processing plants with a total flow rate of 6.99 MMSCFD. Analysis of result from modeling shows that Single column overhead recycle process has a total product recovery of 97.2 % while Conventional fractionation process has a total recovery of 88.5 %, the require energy margin between the alternatives is about 38.9 % in favor of conventional process and the fixed capital cost is in the favor of Single column process. Sensitive to choosing the most economic option of LPG recovery between the conventional process and SCORE process is the recovery level of LPG from each of the options, total energy required and the cost of the equipment. From the analysis, it shows that, it is more economical to use the Single column overhead recycle process, as compared to conventional fractionation process.
Comparative Economic Investigation Options for Liquefied Petroleum Gas Production from Natural Gas Liquids
doi:10.11648/j.ajche.s.2015030201.17
American Journal of Chemical Engineering
2015-06-30
© Science Publishing Group
A. B. Raheem
A. Hassan
S. A. Samsudin
Z. Z. Noor
A. Adebobajo
Comparative Economic Investigation Options for Liquefied Petroleum Gas Production from Natural Gas Liquids
3
2
69
69
2015-06-30
2015-06-30
10.11648/j.ajche.s.2015030201.17
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030201.17
© Science Publishing Group
Study of Relationship between Flotation Rate and Bubble Surface Area Flux using Bubble-Particle Attachment Efficiency
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030202.12
Understanding the attachment micro process is a fundamental step toward predicting the rate constant of flotation kinetics. In this research, the effect of bubble-particle attachment efficiency on k-Sb relationship was investigated under Yoon, Stokes and Potential conditions. Maximum Stokes attachment efficiency obtained was 55.9% with particle size of -37 µm, Sbof 34.2 1/s and flotation rate of 1.65 1/min. Stokes attachment efficiency was less than Yoon efficiency and it seems to be a suitable equation for predicting attachment efficiency. Furthermore, three different models were obtained for estimating attachment efficiency usingk-Sb relationship.
Understanding the attachment micro process is a fundamental step toward predicting the rate constant of flotation kinetics. In this research, the effect of bubble-particle attachment efficiency on k-Sb relationship was investigated under Yoon, Stokes and Potential conditions. Maximum Stokes attachment efficiency obtained was 55.9% with particle size of -37 µm, Sbof 34.2 1/s and flotation rate of 1.65 1/min. Stokes attachment efficiency was less than Yoon efficiency and it seems to be a suitable equation for predicting attachment efficiency. Furthermore, three different models were obtained for estimating attachment efficiency usingk-Sb relationship.
Study of Relationship between Flotation Rate and Bubble Surface Area Flux using Bubble-Particle Attachment Efficiency
doi:10.11648/j.ajche.s.2015030202.12
American Journal of Chemical Engineering
2015-01-27
© Science Publishing Group
Behzad Shahbazi
Study of Relationship between Flotation Rate and Bubble Surface Area Flux using Bubble-Particle Attachment Efficiency
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2
12
12
2015-01-27
2015-01-27
10.11648/j.ajche.s.2015030202.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030202.12
© Science Publishing Group
Effect of Frother on Bubble-Particle Collision Probability of Fine Particles
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030202.11
The frothers are influence on the ability of bubbles to collect particles from the pulp and carry them to the froth layer. In this study the effect of type and dosage of frothers on bubble-particle collision probability and dispersion of fine particles was investigated. Therefore, collision probability of fine particles was calculated using frothers such as MIBC, Pine Oil, and Poly propylene glycol with concentration of 0, 25, 50 and 75 g/t respectively. According to this study, as the particle size increased the probability of collision increased but with using Poly Propylene Glycol, MIBC and Pine Oil, probability of collision increased, respectively. Under Potential flow conditions, Maximum collision probability was obtained 27.27% with Poly Propylene Glycol dosage of 75 g/t and particle size of 50 µm.
The frothers are influence on the ability of bubbles to collect particles from the pulp and carry them to the froth layer. In this study the effect of type and dosage of frothers on bubble-particle collision probability and dispersion of fine particles was investigated. Therefore, collision probability of fine particles was calculated using frothers such as MIBC, Pine Oil, and Poly propylene glycol with concentration of 0, 25, 50 and 75 g/t respectively. According to this study, as the particle size increased the probability of collision increased but with using Poly Propylene Glycol, MIBC and Pine Oil, probability of collision increased, respectively. Under Potential flow conditions, Maximum collision probability was obtained 27.27% with Poly Propylene Glycol dosage of 75 g/t and particle size of 50 µm.
Effect of Frother on Bubble-Particle Collision Probability of Fine Particles
doi:10.11648/j.ajche.s.2015030202.11
American Journal of Chemical Engineering
2015-01-27
© Science Publishing Group
Behzad Shahbazi
Effect of Frother on Bubble-Particle Collision Probability of Fine Particles
3
2
5
5
2015-01-27
2015-01-27
10.11648/j.ajche.s.2015030202.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.s.2015030202.11
© Science Publishing Group
Impact of Alkali Concentration and Metakaolin Content on Accelerated Ageing of Egyptian Slag
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20150303.11
The present work aims to study the coupled effect of alkali concentration and metakaolin (MK) on the resistivity of ground granulated blast-furnace slag (GGBFS) to strength regression during ageing. GGBFS was activated by 6 and 10 wt., % containing mixture of sodium hydroxide (SH) and liquid sodium silicate (LSS) at a ratio of 1:1, respectively (namely GGBFS6 and GGBFS10). On the other hand, GGBFS10 was replaced by 10, 20, 30, 40 and 50 wt., % of MK, respectively. All hardened specimens were cured in 100% relative humidity (RH) at 37 ± 2°C for 28 days (zero time) then, aged at 95°C for 56 days. Experimental results showed that, the pH value of alkali activated samples (AAS) decreased as the amount of MK increased. Also, the pH of AAS derived from GGBFS10 was higher than that of GGBFS6. The strength regression resistivity (SRR) during accelerated ageing enhanced with the decrease of alkali concentration. The compressive strength for different investigated mixes was evaluated. Also, some selected hydration products were analyzed using infrared spectroscopy (FTIR), thermo-gravimetric analysis (TG/DTG) and X- ray diffraction (XRD) techniques to determine the mineralogical phase transition. The results of mechanical properties are in a good agreement with those of FTIR, TG/DTG and XRD techniques and confirm that the SRR during ageing increases with MK content.
The present work aims to study the coupled effect of alkali concentration and metakaolin (MK) on the resistivity of ground granulated blast-furnace slag (GGBFS) to strength regression during ageing. GGBFS was activated by 6 and 10 wt., % containing mixture of sodium hydroxide (SH) and liquid sodium silicate (LSS) at a ratio of 1:1, respectively (namely GGBFS6 and GGBFS10). On the other hand, GGBFS10 was replaced by 10, 20, 30, 40 and 50 wt., % of MK, respectively. All hardened specimens were cured in 100% relative humidity (RH) at 37 ± 2°C for 28 days (zero time) then, aged at 95°C for 56 days. Experimental results showed that, the pH value of alkali activated samples (AAS) decreased as the amount of MK increased. Also, the pH of AAS derived from GGBFS10 was higher than that of GGBFS6. The strength regression resistivity (SRR) during accelerated ageing enhanced with the decrease of alkali concentration. The compressive strength for different investigated mixes was evaluated. Also, some selected hydration products were analyzed using infrared spectroscopy (FTIR), thermo-gravimetric analysis (TG/DTG) and X- ray diffraction (XRD) techniques to determine the mineralogical phase transition. The results of mechanical properties are in a good agreement with those of FTIR, TG/DTG and XRD techniques and confirm that the SRR during ageing increases with MK content.
Impact of Alkali Concentration and Metakaolin Content on Accelerated Ageing of Egyptian Slag
doi:10.11648/j.ajche.20150303.11
American Journal of Chemical Engineering
2015-06-19
© Science Publishing Group
Hamdy Abd El-Aziz Abdel Gawwad
Hesham Mohamed Khater
Saleh Abd El-Aleem Mohamed
Impact of Alkali Concentration and Metakaolin Content on Accelerated Ageing of Egyptian Slag
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3
38
38
2015-06-19
2015-06-19
10.11648/j.ajche.20150303.11
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20150303.11
© Science Publishing Group
Kinetic Parameters Survey for Manufacture of Pralidoxime
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20150303.12
Chemical agents represent a serious threat to the modern world. Among them, they stand out nerve agents because of its high lethality and dangerousness. They are typically organophosphate compounds, which act by inhibiting acetylcholinesterase, a key enzyme in the transmission of nerve impulses process. There are several forms of treatment for organophosphate poisoning, and pralidoxime (2-PAM) is the drug most used as reactivator of acetylcholinesterase. In this work, we developed the first three steps for the synthesis of 2-PAM, with the objective of obtaining data to calculate the kinetic parameters of these steps. These parameters may be used for the manufacture of 2-PAM in semi-pilot scale. Through the studies conducted it has been found that the preparation of the oxime has very rapid kinetics.
Chemical agents represent a serious threat to the modern world. Among them, they stand out nerve agents because of its high lethality and dangerousness. They are typically organophosphate compounds, which act by inhibiting acetylcholinesterase, a key enzyme in the transmission of nerve impulses process. There are several forms of treatment for organophosphate poisoning, and pralidoxime (2-PAM) is the drug most used as reactivator of acetylcholinesterase. In this work, we developed the first three steps for the synthesis of 2-PAM, with the objective of obtaining data to calculate the kinetic parameters of these steps. These parameters may be used for the manufacture of 2-PAM in semi-pilot scale. Through the studies conducted it has been found that the preparation of the oxime has very rapid kinetics.
Kinetic Parameters Survey for Manufacture of Pralidoxime
doi:10.11648/j.ajche.20150303.12
American Journal of Chemical Engineering
2015-07-14
© Science Publishing Group
Daniel Antonio Shimizu Kitagawa
Sabrina Teixeira Martinez
Erick Braga Ferrao Galante
Tanos Celmar Costa Franca
Kinetic Parameters Survey for Manufacture of Pralidoxime
3
3
51
51
2015-07-14
2015-07-14
10.11648/j.ajche.20150303.12
http://www.sciencepublishinggroup.com/journal/paperinfo.aspx?journalid=224&doi=10.11648/j.ajche.20150303.12
© Science Publishing Group