Jackson Akpa | R.S.U.S.T - Academia.edu (original) (raw)
Papers by Jackson Akpa
In this paper the non-equilibrium plasma under atmospheric pressure generated by parallel plate d... more In this paper the non-equilibrium plasma under atmospheric pressure generated by parallel plate dielectric barrier discharge (DBD) system was investigated. The experiments were done by using two high voltage power supply, one (0-15 kV, 50 Hz) and other (0-20 kV, 100-1500 kHz). TheI-V characteristic curves, power consumed and breakdown voltage were studied. A homogeneous and steady nonthermal plasma has been observed between the electrodes with gap space (1,2 and 3 mm). A sheets of glass with thickness (1,2, and 3 mm)were used as a dielectric between the electrodes. Our results shows that the power consumed in DBD system was less (100 W), also it was increased with the glass thickness, gap space and frequency of the applied voltage. It is found that the breakdown voltage in our experiment conditions at 1 atm. pressure was increased with the gap space and decreased with the frequency of the applies voltage.
European Journal of Lipid Science and Technology
This paper presents mechanistic kinetic model of hydrocracking-lumps of series-parallel reactions... more This paper presents mechanistic kinetic model of hydrocracking-lumps of series-parallel reactions of hydrocarbons fractions in reactor plant of Alesa-Eleme. The crude oil fractions kinetic parameters were determined mathematically e.g. activation energies, rate constant, and equilibrium constant of the fractions. The results obtained are presented in figures 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 and 14; with the profiles depicting the actual dynamics of mole fractions of feed fractions conversion with space-time and the temperature effects in reactor 1, 2, and 3. These profiles are in agreement with typical hydrocracking process of improved products for blending into premium motor spirit in refining activities.
A computer aided adiabatic, non-isothermal plug flow reactor was designed for the Non-Catalytic P... more A computer aided adiabatic, non-isothermal plug flow reactor was designed for the Non-Catalytic Partial Oxidation of methane to Synthesis gas. Design equations for determining the functional dimensions and parameters of the reactor were developed and used to develop the design package for the reactor. The design equations were solved using MathLab and simulated with SimuLink 7.5 to determine optimum values/range of the functional parameters. The optimum values obtained were used to run the design program for a hypothetical reactor processing 600mmscf per day of natural gas. Simulation results showed that the functional parameters: space time and yield of products increases with increase in methane fractional conversion, while space velocity and selectivity decreases. Operating at high pressure (60 -70)bar, increases the selectivity of partial methane oxidation reaction, molar flow rate of synthesis gas (desired product) and space velocity, but decreases space time and reactor length...
Journal of Applied Sciences
The environmental and health risks associated with improper handling of waste bones will be great... more The environmental and health risks associated with improper handling of waste bones will be greatly reduced if bone wastes generated from the abattoirs are converted to useful products. Waste cattle bones have been successfully used in the production of glue. The quality of the produced glue was ascertained by testing for quality indicators such as moisture content, pH, density, ash content and viscosity. The values of these quality indicators were greatly improved on investigation of the effects of water quantity and ratio of glue volume to polyvinyl volume used. The values of these quality indicators for the final glue produced with the new raw materials mix compared favorably with values of standard glue with maximum deviation of 0.20 for the ash content.
Activated carbon was produced from three carbon rich agricultural waste materials; bamboo, coconu... more Activated carbon was produced from three carbon rich agricultural waste materials; bamboo, coconut and palm kernel shells by pyrolysis and chemical activation (using tri oxo nitrate (v) acid (HNO 3)). The activated carbons were characterized and used as adsorbent for the removal of benzene from aqueous solution. The effects of various parameters such as particle size, adsorbent dosage and initial benzene concentration on the adsorption efficiency of the activated carbons were investigated. Benzene adsorption decreased with increase in particle size of activated carbon, decrease was minimal with activated carbon produced from bamboo. Benzene adsorption increased with increase in adsorbent dosage. Increase in initial benzene concentration resulted in increased adsorption using activated carbon from coconut and palm kernel shells; a decrease in adsorption using activated carbon from bamboo.
Alternative thickeners to an industrial thickener (natrosol) in the production of emulsion paints... more Alternative thickeners to an industrial thickener (natrosol) in the production of emulsion paints were investigated. Four starch grades; native starch, native starch modified with sodium acetate, native starch modified with sodium acetate plus fumaric acid and native starch modified with sodium acetate mixed with adipic acid were tested as possible alternatives to natrosol. The physio-chemical properties such as viscosity, density, pH, drying time and durability of the paints produced with these starches as thickeners were compared with paint produced with the industrial thickener (natrosol). There were improvements in these properties in paints produced from the modified starches compared with paint produced from the native starch. The paint produced with native starch modified with sodium acetate and furmaric acid had properties closest to the paint produced with the industrial thickener. The viscosity, density, pH and drying time of the paint produced with sodium acetate and furm...
Dynamic models for the simulation of an industrial Fluid catalytic cracking riser reactor have be... more Dynamic models for the simulation of an industrial Fluid catalytic cracking riser reactor have been developed on the basis of material and energy balance equations. A four-lump kinetic scheme was used to describe the reactions taking place in the riser. The riser is modeled as a one dimensional plug flow reactor without axial dispersion. The models developed were a set of coupled partial differential equations. These were transformed using the method of lines into a set of ordinary differential equations with respect to time using a finite difference approximation of the spatial derivatives. The resulting differential equations were solved using MathLAB Ode solver. The dynamic responses of the open loop riser reactor to changes in the riser inlet temperature, mass flow rate of gas oil and catalyst-to-oil ratio were investigated. The open loop response of the riser temperature to step changes in the feed flow rate, catalyst-to-oil ratio and riser inlet temperature shows an initial os...
IOSR Journal of Engineering, 2014
Models' describing the steady state behavior of the fluidized bed reactor for catalytic cracking ... more Models' describing the steady state behavior of the fluidized bed reactor for catalytic cracking of gas oil has been presented. The four-lump kinetic scheme was used to describe the cracking reactions occurring in the reactor while the two-phase hypothesis comprising of the bubble and the emulsion phases of Kunii and Levenspiel was used to describe the fluidized bed models. The model equations consisted of sets of non linear first order differential equations and sets of quadratic equations. The differential equations were integrated numerically using the fourth order Runge-Kutta algorithm while the quadratic equations were solved using formulae method. Results predicted by the model were validated using data obtained from a operating plant, deviations of -21. 99%, 9.85%, 5.27%, and 4.12% were obtained for the conversion of gas oil, yields of gasoline, gases and coke respectively. The results shows that plug flow-plug flow combination of the fluidized bed gave a higher conversion of gasoil than the plug flow-CSTR model. Sensitivity analyses showed that superficial velocity, bubble diameter, catalyst bed height, reactor temperature, catalyst-to-gasoil ratio and the diameter of reactor are important process variables that affect the yield of the products.
In recent years, Orthogonal Frequency Division Multiplexing (OFDM) has gained significant attenti... more In recent years, Orthogonal Frequency Division Multiplexing (OFDM) has gained significant attention and is preferred for transmission over a dispersive channel. It is because of its several advantages such as high spectral efficiency, low implementation complexity, less vulnerability to echoes and non–linear distortion. However, it has few limitations such as peak-to-average-power ratio (PAPR) and bit error rate (BER), which determines the system's power efficiency. High PAPR is one of the major drawbacks in OFDM systems, which causes a significant level of signal distortions, when the modulated signals are amplified through high power amplifiers (HPAs). Also, a high PAPR and, in addition, high noise (e.g. AWGN) may significantly distort the signal, resulting in high BER on demodulation of the received signal. Therefore, PAPR & BER reduction is very essential. For this purpose, the research reported in this paper is focused on providing a solution to the same problem. More speci...
Mathematical models that can be used to predict the transient behavior of heat exchangers in a He... more Mathematical models that can be used to predict the transient behavior of heat exchangers in a Heat exchanger Network (HEN) have been developed. This analysis is aimed at predicting thermal transients in Heat Exchanger Networks due to temperature fluctuations of inlet streams. This model is used to predict thermal transient of the heat exchanger networks in the crude distillation unit of the New Port-Harcourt refinery. The response of heat exchangers in the entire network to transient input (sinusoidal change in inlet temperature of the cold stream) was investigated. A finite difference numerical scheme is used to develop a solution algorithm for solving the set of partial differential model equations. The results reveals the effect of inlet temperature change on the process streams and possible points where temperature control is required in the heat exchanger networks of the New Port Harcourt refinery
The production of adhesive from cassava root IITA variety TMS 94/0026 was performed. Applications... more The production of adhesive from cassava root IITA variety TMS 94/0026 was performed. Applications of starch based adhesive are limited due to its unsuitable properties. Improvements in properties of adhesives produced were achieved by investigating the effects of temperature, mass (concentration) of the viscosity enhancer /stabilizer (borax) and gelatinization modifier (acidic, hydrogen chloride acid (HCl) and basic sodium hydroxide (NaOH)) and its concentration on the properties (viscosity, density and pH) of the adhesive produced. The effect of the gelatinization modifier (HCL and NaOH) on the drying time and bond strength of the adhesive was also investigated. Results obtained provide a wide range of conditions for producing starch-based adhesives for diverse applications and required properties. The adhesives produced with sodium hydroxide as its gelatinization modifier had a stronger bond and a maximum drying time of 7.20 minutes compared to a drying time of 4.16 minutes for the adhesive produced with hydrogen chloride acid.
The pinch analysis of the heat exchanger networks in the crude distillation unit of the New Port-... more The pinch analysis of the heat exchanger networks in the crude distillation unit of the New Port-Harcourt refinery has been performed. This analysis is aimed at ascertaining the energy efficiency and operation of the heat exchangers used in preheating the crude. Process data of the heat exchanger networks (HEN) were collected to formulate a problem table and used in Aspen-Pinch ® software for pinch analysis of the networks. The software produced the composite and grand composite curves, the grid representation and target reports. From these, the minimum heating and cooling requirements of the entire network, the process streams not properly matched and the heat exchangers not properly placed were obtained. The analysis indicated that a total of 98916.1 KW hot utility, 8298.7 KW cold utility were not utilized within the network (poor process stream matching) and that ten heat exchangers were not properly placed. Hence the heat exchangers in the crude distillation unit need to be retrofitted to ensure adequate heat recovery, process to process integration and efficient energy utilization within the network.
Cassava starch modification by cross-linking using four different reagents (ammonium phosphate, s... more Cassava starch modification by cross-linking using four different reagents (ammonium phosphate, sodium acetate, sodium acetate with adipic acid, sodium acetate with fumaric acid) was performed. Functional properties (ash content, pH, moisture content, gelatinization temperature, swelling power, swelling volume, solubility and viscosity) of the modified starch were compared with those of the native cassava starch. The modified starches had varying degrees of improvements in properties in descending order as: modification with sodium acetate, ammonium phosphate, sodium acetate with adipic acid, sodium acetate with fumaric acid. Starch modified with sodium acetate and ammonium phosphate showed great improvement in their gelatinization temperature with values of 79oF and 75oF compared with 69oF of the native starch, solubility of 66.7% and 37.1% compared with 0% of the native cassava starch and had lower and stable viscosities.
Mathematical models for predicting the fractional conversion of ethylbenzene and yields of produc... more Mathematical models for predicting the fractional conversion of ethylbenzene and yields of products in a catalytic membrane reactor for the dehydrogenation of ethylbenzene were developed. The mathematical models developed consisted of nonlinear simultaneous differential equations which were solved numerically using the 4th order Runge-kuta algorithm. Prediction by the models of fractional conversion and yields of product compare favorably with outputs of an industrial reactor with maximum deviations of 0.175. The models were subsequently used to simulate the effects of feed inlet temperature, feed molar ratio of steam and ethylbenzene and inlet pressure on the reactor performance.
Experimental corrosion rate data of two stainless steel grades (430 and 316) when subjected to a ... more Experimental corrosion rate data of two stainless steel grades (430 and 316) when subjected to a typical oil bearing marine environment have been generated. Empirical model equations for predicting the corrosion rates of the two steel grades were developed using the dimensional analysis of Bukinham-Pi method. Regression analysis was used to curve fit the experimental data, thus obtain the correlation factor in the model equations developed. The model equations were used to predict the corrosion rates for the two steel grades and the predicted rates were found to match the experimental rates perfectly in the time interval investigated.
Modelsofanabsorberfordehydrationofnaturalgasusingtriethyleneglycolarepresented.Themodelsweredevel... more Modelsofanabsorberfordehydrationofnaturalgasusingtriethyleneglycolarepresented.Themodelsweredevelopedbyapplying the law of conservation of mass and energy to predict the variation of water content of gas and the temperature of the gas and liquid with time along the packing height. The models were integrated numerically using the finite divided difference scheme and incorporated into the MATLAB code. The results obtained agreed reasonably well with industrial plant data obtained from an SPDC TEGunit in Niger-Delta, Nigeria. Model prediction showed a percentage deviation of 8.65% for gas water content and 3.41% and 9.18% for exit temperature of gas and liquid, respectively.
Mathematical models for the prediction of water content, gas and solvent temperatures of the abso... more Mathematical models for the prediction of water content, gas and solvent temperatures of the absorber of a natural gas glycol dehydration facility were developed. The models developed contain contributions from bulk and diffusion flows, however only the effect of diffusion on the process occurring in the absorber was studied. The developed models were second order partial differential equations. The Laplace transform technique was applied to obtain analytical solutions of the model equations. The models were validated using the plant data from an SPDC TEG unit in Gbaran Ubie, Bayelsa State. The results showed a reasonable agreement between the model predictions and industrial plant data. The model predicted the amount of water in the gas stream at the end of the absorption process very accurately with a deviation of 0%., the gas and solvent temperatures with deviations of 1.584% and 2.844% respectively. These results show that diffusion alone can be use to accurately model the absorption process. The effects of certain process variables such as residence time, gas inlet water content, mass and thermal Diffusivities of the gas on the performance of the absorber was studied
Steady state models for a multi-component crude distillation column have been developed from the ... more Steady state models for a multi-component crude distillation column have been developed from the MESH equations. The equations developed are capable of predicting the concentrations (mole fractions) and temperature of any component/fraction of interest from the mixture on the trays of the column. The accuracy of the models was ascertained with plant data of the crude distillation unit of the Port-Harcourt Refinery. The models applied to this distillation column produced a set of forty eight coupled algebraic equations for any component/fraction of interest. These equations were transformed into a matrix and solve by matrix inversion using the Mathlab solver. The model results of the concentrations and temperatures for five components compared favorably with output values from the distillation unit with maximum deviations of 8.33% and 6.62% respectively. The developed model also accurately predicted the tray of withdrawal of the five components/fractions in the distillation column. The models were therefore used to simulate the effects of feed flow rate and feed tray position on the efficiency of the distillation column.
A batch reactor model for the fermentation of palm wine to ethanol and acetic acid has been devel... more A batch reactor model for the fermentation of palm wine to ethanol and acetic acid has been developed. The kinetics of alcohol and acetic acid production from palm wine was carried out in a laboratory scale experimental batch reactor. 1.5 liters of palm wine was reacted with yeast (Saccharomyce cerevisiae) strain for 12 hours for alcohol production, after which bacteria (lactobacillus) was introduced for another 12 hours for acetic acid production. Biomass, ethanol, acetic acid, and glucose concentrations were sampled every 2 hours. A monod type cell growth kinetic model that accounts for product inhibition was used to approximate the fermentation process. Experimental model fitting technique was used to estimate the kinetic parameters in the model. The reactor models developed were a set of coupled ordinary differential equations and were integrated numerically using the 4th order runge kutta technique. The model equations predicted the experimental results of the concentration of substrate utilized, biomass and products produced accurately with a maximum deviation of 0.402%, hence the models were used for the batch reactor simulation. The effects of initial substrate and biomass concentration on reactor efficiency were investigated.
In this paper the non-equilibrium plasma under atmospheric pressure generated by parallel plate d... more In this paper the non-equilibrium plasma under atmospheric pressure generated by parallel plate dielectric barrier discharge (DBD) system was investigated. The experiments were done by using two high voltage power supply, one (0-15 kV, 50 Hz) and other (0-20 kV, 100-1500 kHz). TheI-V characteristic curves, power consumed and breakdown voltage were studied. A homogeneous and steady nonthermal plasma has been observed between the electrodes with gap space (1,2 and 3 mm). A sheets of glass with thickness (1,2, and 3 mm)were used as a dielectric between the electrodes. Our results shows that the power consumed in DBD system was less (100 W), also it was increased with the glass thickness, gap space and frequency of the applied voltage. It is found that the breakdown voltage in our experiment conditions at 1 atm. pressure was increased with the gap space and decreased with the frequency of the applies voltage.
European Journal of Lipid Science and Technology
This paper presents mechanistic kinetic model of hydrocracking-lumps of series-parallel reactions... more This paper presents mechanistic kinetic model of hydrocracking-lumps of series-parallel reactions of hydrocarbons fractions in reactor plant of Alesa-Eleme. The crude oil fractions kinetic parameters were determined mathematically e.g. activation energies, rate constant, and equilibrium constant of the fractions. The results obtained are presented in figures 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 and 14; with the profiles depicting the actual dynamics of mole fractions of feed fractions conversion with space-time and the temperature effects in reactor 1, 2, and 3. These profiles are in agreement with typical hydrocracking process of improved products for blending into premium motor spirit in refining activities.
A computer aided adiabatic, non-isothermal plug flow reactor was designed for the Non-Catalytic P... more A computer aided adiabatic, non-isothermal plug flow reactor was designed for the Non-Catalytic Partial Oxidation of methane to Synthesis gas. Design equations for determining the functional dimensions and parameters of the reactor were developed and used to develop the design package for the reactor. The design equations were solved using MathLab and simulated with SimuLink 7.5 to determine optimum values/range of the functional parameters. The optimum values obtained were used to run the design program for a hypothetical reactor processing 600mmscf per day of natural gas. Simulation results showed that the functional parameters: space time and yield of products increases with increase in methane fractional conversion, while space velocity and selectivity decreases. Operating at high pressure (60 -70)bar, increases the selectivity of partial methane oxidation reaction, molar flow rate of synthesis gas (desired product) and space velocity, but decreases space time and reactor length...
Journal of Applied Sciences
The environmental and health risks associated with improper handling of waste bones will be great... more The environmental and health risks associated with improper handling of waste bones will be greatly reduced if bone wastes generated from the abattoirs are converted to useful products. Waste cattle bones have been successfully used in the production of glue. The quality of the produced glue was ascertained by testing for quality indicators such as moisture content, pH, density, ash content and viscosity. The values of these quality indicators were greatly improved on investigation of the effects of water quantity and ratio of glue volume to polyvinyl volume used. The values of these quality indicators for the final glue produced with the new raw materials mix compared favorably with values of standard glue with maximum deviation of 0.20 for the ash content.
Activated carbon was produced from three carbon rich agricultural waste materials; bamboo, coconu... more Activated carbon was produced from three carbon rich agricultural waste materials; bamboo, coconut and palm kernel shells by pyrolysis and chemical activation (using tri oxo nitrate (v) acid (HNO 3)). The activated carbons were characterized and used as adsorbent for the removal of benzene from aqueous solution. The effects of various parameters such as particle size, adsorbent dosage and initial benzene concentration on the adsorption efficiency of the activated carbons were investigated. Benzene adsorption decreased with increase in particle size of activated carbon, decrease was minimal with activated carbon produced from bamboo. Benzene adsorption increased with increase in adsorbent dosage. Increase in initial benzene concentration resulted in increased adsorption using activated carbon from coconut and palm kernel shells; a decrease in adsorption using activated carbon from bamboo.
Alternative thickeners to an industrial thickener (natrosol) in the production of emulsion paints... more Alternative thickeners to an industrial thickener (natrosol) in the production of emulsion paints were investigated. Four starch grades; native starch, native starch modified with sodium acetate, native starch modified with sodium acetate plus fumaric acid and native starch modified with sodium acetate mixed with adipic acid were tested as possible alternatives to natrosol. The physio-chemical properties such as viscosity, density, pH, drying time and durability of the paints produced with these starches as thickeners were compared with paint produced with the industrial thickener (natrosol). There were improvements in these properties in paints produced from the modified starches compared with paint produced from the native starch. The paint produced with native starch modified with sodium acetate and furmaric acid had properties closest to the paint produced with the industrial thickener. The viscosity, density, pH and drying time of the paint produced with sodium acetate and furm...
Dynamic models for the simulation of an industrial Fluid catalytic cracking riser reactor have be... more Dynamic models for the simulation of an industrial Fluid catalytic cracking riser reactor have been developed on the basis of material and energy balance equations. A four-lump kinetic scheme was used to describe the reactions taking place in the riser. The riser is modeled as a one dimensional plug flow reactor without axial dispersion. The models developed were a set of coupled partial differential equations. These were transformed using the method of lines into a set of ordinary differential equations with respect to time using a finite difference approximation of the spatial derivatives. The resulting differential equations were solved using MathLAB Ode solver. The dynamic responses of the open loop riser reactor to changes in the riser inlet temperature, mass flow rate of gas oil and catalyst-to-oil ratio were investigated. The open loop response of the riser temperature to step changes in the feed flow rate, catalyst-to-oil ratio and riser inlet temperature shows an initial os...
IOSR Journal of Engineering, 2014
Models' describing the steady state behavior of the fluidized bed reactor for catalytic cracking ... more Models' describing the steady state behavior of the fluidized bed reactor for catalytic cracking of gas oil has been presented. The four-lump kinetic scheme was used to describe the cracking reactions occurring in the reactor while the two-phase hypothesis comprising of the bubble and the emulsion phases of Kunii and Levenspiel was used to describe the fluidized bed models. The model equations consisted of sets of non linear first order differential equations and sets of quadratic equations. The differential equations were integrated numerically using the fourth order Runge-Kutta algorithm while the quadratic equations were solved using formulae method. Results predicted by the model were validated using data obtained from a operating plant, deviations of -21. 99%, 9.85%, 5.27%, and 4.12% were obtained for the conversion of gas oil, yields of gasoline, gases and coke respectively. The results shows that plug flow-plug flow combination of the fluidized bed gave a higher conversion of gasoil than the plug flow-CSTR model. Sensitivity analyses showed that superficial velocity, bubble diameter, catalyst bed height, reactor temperature, catalyst-to-gasoil ratio and the diameter of reactor are important process variables that affect the yield of the products.
In recent years, Orthogonal Frequency Division Multiplexing (OFDM) has gained significant attenti... more In recent years, Orthogonal Frequency Division Multiplexing (OFDM) has gained significant attention and is preferred for transmission over a dispersive channel. It is because of its several advantages such as high spectral efficiency, low implementation complexity, less vulnerability to echoes and non–linear distortion. However, it has few limitations such as peak-to-average-power ratio (PAPR) and bit error rate (BER), which determines the system's power efficiency. High PAPR is one of the major drawbacks in OFDM systems, which causes a significant level of signal distortions, when the modulated signals are amplified through high power amplifiers (HPAs). Also, a high PAPR and, in addition, high noise (e.g. AWGN) may significantly distort the signal, resulting in high BER on demodulation of the received signal. Therefore, PAPR & BER reduction is very essential. For this purpose, the research reported in this paper is focused on providing a solution to the same problem. More speci...
Mathematical models that can be used to predict the transient behavior of heat exchangers in a He... more Mathematical models that can be used to predict the transient behavior of heat exchangers in a Heat exchanger Network (HEN) have been developed. This analysis is aimed at predicting thermal transients in Heat Exchanger Networks due to temperature fluctuations of inlet streams. This model is used to predict thermal transient of the heat exchanger networks in the crude distillation unit of the New Port-Harcourt refinery. The response of heat exchangers in the entire network to transient input (sinusoidal change in inlet temperature of the cold stream) was investigated. A finite difference numerical scheme is used to develop a solution algorithm for solving the set of partial differential model equations. The results reveals the effect of inlet temperature change on the process streams and possible points where temperature control is required in the heat exchanger networks of the New Port Harcourt refinery
The production of adhesive from cassava root IITA variety TMS 94/0026 was performed. Applications... more The production of adhesive from cassava root IITA variety TMS 94/0026 was performed. Applications of starch based adhesive are limited due to its unsuitable properties. Improvements in properties of adhesives produced were achieved by investigating the effects of temperature, mass (concentration) of the viscosity enhancer /stabilizer (borax) and gelatinization modifier (acidic, hydrogen chloride acid (HCl) and basic sodium hydroxide (NaOH)) and its concentration on the properties (viscosity, density and pH) of the adhesive produced. The effect of the gelatinization modifier (HCL and NaOH) on the drying time and bond strength of the adhesive was also investigated. Results obtained provide a wide range of conditions for producing starch-based adhesives for diverse applications and required properties. The adhesives produced with sodium hydroxide as its gelatinization modifier had a stronger bond and a maximum drying time of 7.20 minutes compared to a drying time of 4.16 minutes for the adhesive produced with hydrogen chloride acid.
The pinch analysis of the heat exchanger networks in the crude distillation unit of the New Port-... more The pinch analysis of the heat exchanger networks in the crude distillation unit of the New Port-Harcourt refinery has been performed. This analysis is aimed at ascertaining the energy efficiency and operation of the heat exchangers used in preheating the crude. Process data of the heat exchanger networks (HEN) were collected to formulate a problem table and used in Aspen-Pinch ® software for pinch analysis of the networks. The software produced the composite and grand composite curves, the grid representation and target reports. From these, the minimum heating and cooling requirements of the entire network, the process streams not properly matched and the heat exchangers not properly placed were obtained. The analysis indicated that a total of 98916.1 KW hot utility, 8298.7 KW cold utility were not utilized within the network (poor process stream matching) and that ten heat exchangers were not properly placed. Hence the heat exchangers in the crude distillation unit need to be retrofitted to ensure adequate heat recovery, process to process integration and efficient energy utilization within the network.
Cassava starch modification by cross-linking using four different reagents (ammonium phosphate, s... more Cassava starch modification by cross-linking using four different reagents (ammonium phosphate, sodium acetate, sodium acetate with adipic acid, sodium acetate with fumaric acid) was performed. Functional properties (ash content, pH, moisture content, gelatinization temperature, swelling power, swelling volume, solubility and viscosity) of the modified starch were compared with those of the native cassava starch. The modified starches had varying degrees of improvements in properties in descending order as: modification with sodium acetate, ammonium phosphate, sodium acetate with adipic acid, sodium acetate with fumaric acid. Starch modified with sodium acetate and ammonium phosphate showed great improvement in their gelatinization temperature with values of 79oF and 75oF compared with 69oF of the native starch, solubility of 66.7% and 37.1% compared with 0% of the native cassava starch and had lower and stable viscosities.
Mathematical models for predicting the fractional conversion of ethylbenzene and yields of produc... more Mathematical models for predicting the fractional conversion of ethylbenzene and yields of products in a catalytic membrane reactor for the dehydrogenation of ethylbenzene were developed. The mathematical models developed consisted of nonlinear simultaneous differential equations which were solved numerically using the 4th order Runge-kuta algorithm. Prediction by the models of fractional conversion and yields of product compare favorably with outputs of an industrial reactor with maximum deviations of 0.175. The models were subsequently used to simulate the effects of feed inlet temperature, feed molar ratio of steam and ethylbenzene and inlet pressure on the reactor performance.
Experimental corrosion rate data of two stainless steel grades (430 and 316) when subjected to a ... more Experimental corrosion rate data of two stainless steel grades (430 and 316) when subjected to a typical oil bearing marine environment have been generated. Empirical model equations for predicting the corrosion rates of the two steel grades were developed using the dimensional analysis of Bukinham-Pi method. Regression analysis was used to curve fit the experimental data, thus obtain the correlation factor in the model equations developed. The model equations were used to predict the corrosion rates for the two steel grades and the predicted rates were found to match the experimental rates perfectly in the time interval investigated.
Modelsofanabsorberfordehydrationofnaturalgasusingtriethyleneglycolarepresented.Themodelsweredevel... more Modelsofanabsorberfordehydrationofnaturalgasusingtriethyleneglycolarepresented.Themodelsweredevelopedbyapplying the law of conservation of mass and energy to predict the variation of water content of gas and the temperature of the gas and liquid with time along the packing height. The models were integrated numerically using the finite divided difference scheme and incorporated into the MATLAB code. The results obtained agreed reasonably well with industrial plant data obtained from an SPDC TEGunit in Niger-Delta, Nigeria. Model prediction showed a percentage deviation of 8.65% for gas water content and 3.41% and 9.18% for exit temperature of gas and liquid, respectively.
Mathematical models for the prediction of water content, gas and solvent temperatures of the abso... more Mathematical models for the prediction of water content, gas and solvent temperatures of the absorber of a natural gas glycol dehydration facility were developed. The models developed contain contributions from bulk and diffusion flows, however only the effect of diffusion on the process occurring in the absorber was studied. The developed models were second order partial differential equations. The Laplace transform technique was applied to obtain analytical solutions of the model equations. The models were validated using the plant data from an SPDC TEG unit in Gbaran Ubie, Bayelsa State. The results showed a reasonable agreement between the model predictions and industrial plant data. The model predicted the amount of water in the gas stream at the end of the absorption process very accurately with a deviation of 0%., the gas and solvent temperatures with deviations of 1.584% and 2.844% respectively. These results show that diffusion alone can be use to accurately model the absorption process. The effects of certain process variables such as residence time, gas inlet water content, mass and thermal Diffusivities of the gas on the performance of the absorber was studied
Steady state models for a multi-component crude distillation column have been developed from the ... more Steady state models for a multi-component crude distillation column have been developed from the MESH equations. The equations developed are capable of predicting the concentrations (mole fractions) and temperature of any component/fraction of interest from the mixture on the trays of the column. The accuracy of the models was ascertained with plant data of the crude distillation unit of the Port-Harcourt Refinery. The models applied to this distillation column produced a set of forty eight coupled algebraic equations for any component/fraction of interest. These equations were transformed into a matrix and solve by matrix inversion using the Mathlab solver. The model results of the concentrations and temperatures for five components compared favorably with output values from the distillation unit with maximum deviations of 8.33% and 6.62% respectively. The developed model also accurately predicted the tray of withdrawal of the five components/fractions in the distillation column. The models were therefore used to simulate the effects of feed flow rate and feed tray position on the efficiency of the distillation column.
A batch reactor model for the fermentation of palm wine to ethanol and acetic acid has been devel... more A batch reactor model for the fermentation of palm wine to ethanol and acetic acid has been developed. The kinetics of alcohol and acetic acid production from palm wine was carried out in a laboratory scale experimental batch reactor. 1.5 liters of palm wine was reacted with yeast (Saccharomyce cerevisiae) strain for 12 hours for alcohol production, after which bacteria (lactobacillus) was introduced for another 12 hours for acetic acid production. Biomass, ethanol, acetic acid, and glucose concentrations were sampled every 2 hours. A monod type cell growth kinetic model that accounts for product inhibition was used to approximate the fermentation process. Experimental model fitting technique was used to estimate the kinetic parameters in the model. The reactor models developed were a set of coupled ordinary differential equations and were integrated numerically using the 4th order runge kutta technique. The model equations predicted the experimental results of the concentration of substrate utilized, biomass and products produced accurately with a maximum deviation of 0.402%, hence the models were used for the batch reactor simulation. The effects of initial substrate and biomass concentration on reactor efficiency were investigated.