Development of a Grid-Based Rural Electrification Design: A Case Study of Ishashi and Ilogbo Communities in Lagos State, South Western Nigeria

This work presents the development of a grid-based rural electrification design using Ishashi and Ilogbocommunities in Lagos State, South Western Nigeria as case studies. Grid-based and off-grid based methods are two commonly employed rural electrification technologies but in this work grid-based method was employed because of its simplicity, flexibility, sustainability and cost effectiveness. Load audits of Ishashi and Ilogbo were carried out to determine their energy demands. To cater for future expansion of both communities, a fifteen year load growth was calculated using the derived load growth equations. Design equations were used to determine ratings and quantities of substation components required for the electrification. The inter-township connection and township distribution network lengths for both Ishashi and Ilogbo were also determined. The proposed electrical model designs for the two communities were implemented using AutoCAD 2012 Version Software. The energy demand of both Ishashi and Ilogbo were respectively 0.91 MW and 0.61 MW and their estimated fifteen years load growth were 3.26 MW and 2.20 MW respectively. The average load demand of both Ishashi and Ilogbo were respectively 1.31 MW and 0.88 MW using a load factor of 0.4. With the use of average load demand, the inter-township connection and township distribution network lengths of Ishashi (2.65 km and 8.72 km respectively) and Ilogbo (1.13 km and 7.44 km respectively), the required quantities of the major substation components required for implementation of developed electrical model designs were obtained

INFLUENCE OF CATALYST QUANTITY AND REACTION TIME ON IN-SITU PRODUCTION OF BIODIESEL FROM RAW CASTOR BEAN SEED USING RESPONSE SURFACE METHODOLOGY

Trans-esterification is the most commonly used methods of biodiesel production. In-situ trans-esterification process uses oil (triglycerides) in seeds directly without the need for initial extraction. The in-situ production of biodiesel from raw castor bean seed with a batch processor was studied at initial catalyst quantity of 0.1, 0.5 and 1.5%, reaction time of 30, 60 and 90 min with a reaction temperature of 600C and alcohol seed ratio of 1:1 using the response surface methodology.  Initial catalyst concentration and reaction time were subjected to central composite experimental design of the response surface methodology.  Initial catalyst quantity and reaction time were found to have significant (P<0.05) effects on the yield of castor biodiesel produced, with increased catalyst quantity giving a negative effect on the yield after an initial amount of between 1.0 and 1.2%.  The reaction time had a positive effect on the yield until after 90 minutes after which biodiesel yield reduced with increased time. The CA-Time interactions influence was small and negative, due to the superior effect of initial catalyst quantity by the formation of by-products (soaps) leading to difficult ester separation from glycerol. A second-order model was obtained to predict the yield as a function of all factors. The model predicted well the observed data with a R2 value of 0.983. The biodiesel produced had properties comparable to the standards of ASTM while the specific gravity was higher than the specified standards

EFFECT OF TEMPERATURE AND PERCENTAGE OF INITIAL CATALYST ON THE IN-SITU PRODUCTION OF BIO-DIESEL FROM CASTOR OIL BEAN SEED USING RESPONSE SURFACE METHODOLOGY

The use of vegetable oil and animal fats for biodiesel production has recently become a great concern because of the competition with food materials.  As the demand for vegetable oil increase tremendously in recent years it has become impossible to justify the use of these oils for fuel production. In-situ trans-esterification process uses the oil (triglycerides) in the oil seed directly without the need for initial extraction as compared with the conventional trans-esterification. Castor oil bean seed contains between 35 and 55% oil and does not compete with food grade oil because of the seed’s toxicity. This study evaluated the effect of temperature and percentage of initial catalyst on yield of castor ethyl ester.  Raw castor oil bean seed kernel at moisture content of 4.68 % (db) was subjected to in-situ trans-esterification in a batch processor with ethanol as the solvent and sodium hydroxide as the catalyst.  Central composite design (CCD) of the Response surface methodology was applied to evaluate the main and interactive effects of initial catalyst amount (0.5 – 1.5%) and reaction temperature (40 – 70OC), on yield of castor ethyl-ester, at reaction time of 120 minutes and alcohol-seed weight ratio of 1:1.  A quadratic non-linear polynomial model was obtained to describe the effect of the factors on yield.  The model was significant (P< 0.05) with a non- significant Lack-of-Fit value (P< 0.05) and R2 value of 0.944. Second order response surfaces and contour plots obtained from the model revealed that initial catalyst amount was the more effective factors on yield while reaction temperature had less effect. The Temperature–percentage of initial catalyst interaction was small and negative, due to the combined effects of formation of by-products (soaps) and saponification. The biodiesel produced from ground castor oil bean seed during this study met the requirements of ASTM standard D6751-02 but specific gravity was higher than the ASTM standard confirming that biodiesel produced from castor bean seed using the in-situ technique can be used as replacement fuel for fossil diesel

Power System’s Voltage Stability Improvement Using Static Var Compensator

In alternating current systems, voltage fluctuation is a common phenomenon. Most of the voltage fluctuation problems result from the changes in the system’s reactive power resulting from excessive supply or consumption of reactive power by the elements of the system and the variation in the consumers’ loads. In this paper, the effect of Static Var Compensator (SVC) in stabilizing power system’s voltage through effective reactive power compensation was investigated. Power flow equations involving voltage drop with/without SVC were developed. SVC modeling equations were also developed and used to determine its parameters. Based on the SVC parameters, SIMULINK blocks were used to implement the phase controlled Thyristor–Controlled-Reactor Fixed-Capacitor (TCR-FC) SVC. The Nigerian 28-bus power system used for the study was also modeled using SIMULINK/MATLAB. The 28-bus system was first simulated without SVC and then with two SVCs located at different buses to obtain the bus voltages in both cases. From the bus voltages the total voltage drops for the system with and without SVC were estimated and compared. The compared results clearly showed that, the system’s voltage drop was reduced by 33.78% indicating a significant improvement in the system’s voltage stability when SVCs were applied

Optimization of in-situ Biodiesel Production from Raw Castor Oil-Bean Seed

Optimization of in-situ biodiesel production from raw castor oil-bean seed was carried out from raw castor bean oil seed (37.9% oil content) by alkaline catalyzed in-situ trans-esterification with Sodium hydroxide as catalyst and ethanol as the solvent in a laboratory batch processor.  Response surface methodology and central composite experimental design was applied to evaluate effects of reaction time (30 -120 min), alcohol/seed weight ratio (0.5 – 2.0), Catalyst amount (0.3 – 1.5%) and reaction temperature (40 – 70OC).  Catalyst amount, reaction temperature and time all had significant main effects (p < 0.05) while Alcohol-seed ratio had only slight effects on yield of castor biodiesel as a main effect but was significantly involved in interactions with other factors.  A modified statistical model comprised of all significant factors and interactions (p < 0.05) obtained by multiple regressions predicted that the highest yield of castor ethyl-ester was 99.5% of expressible oil at the following optimized reaction values; alcohol/seed weight ratio of 0.5, a catalyst./seed weight ratio of 1.31, reaction temperature of 60.33oC, and reaction time of 81.7minutes.  A Taguchi L9(3^4)  optimization experimental design used to confirm the modified model at optimum point and two other points within experimental region produced yield that was significantly comparable to model predictions at 95% confidence level using  a paired t-test. Measured properties of the castor ethyl-ester such as viscosity(5.78mm2/s), pour point (-21.5 oC), flash point (177.12 oC), calorific value (47.76MJ/kg), acid value (0.34 mg KOH/g) and cetane number (48.73) were within the ASTM standard D6751-02 but specific gravity. Keywords: Castor oil-bean seed, biodiesel, in-situ trans-esterification, response surface methodology, optimization, Castor ethyl-este

Influence of catalyst amount and alcohol-seed ratio on the production of bio-diesel from raw castor oil bean seed using in-situ technique

Trans-esterification is the most commonly used methods of biodiesel production. In-situ trans-esterification process uses oil (triglycerides) in seeds directly without the need for initial extraction. The in-situproduction of biodiesel from raw castor bean seed with a batch processor was studied at initial catalyst quantity of 0.1, 0.5 and 1.5%, reaction time of 30, 60 and 90 min with a reaction temperature of 600C and alcohol seed ratio of 1:1 using the response surface methodology. Initial catalyst concen-tration and reaction time were subjected to central composite experimental design of the response surface methodology. Initial catalyst quantity and reaction time were found to have significant (P<0.05) effects on the yield of castor biodiesel produced, with increased catalyst quantity giving a negative effect on the yield after an initial amount of between 1.0 and 1.2%. The reaction time had a positive effect on the yield until after 90 minutes after which biodiesel yield reduced with increased time. The CA-Time interactions influence was small and negative, due to the superior effect of initial catalyst quantity by the formation of by-products (soaps) leading to difficult ester separation from glyc-erol. A second-order model was obtained to predict the yield as a function of all factors. The model predicted well the observed data with a R2 value of 0.983. The biodiesel produced had properties com-parable to the standards of ASTM while the specific gravity was higher than the specified standard

EFFECT OF TEMPERATURE AND PERCENTAGE OF INITIAL CATALYST ON THE IN-SITU PRODUCTION OF BIO-DIESEL FROM CASTOR OIL BEAN SEED USING RESPONSE SURFACE METHODOLOGY

The use of vegetable oil and animal fats for biodiesel production has recently become a great concern because of the competition with food materials. As the demand for vegetable oil increase tremendously in recent years it has become impossible to justify the use of these oils for fuel production. Insitu trans-esterification process uses the oil (triglycerides) in the oil seed directly without the need for initial extraction as compared with the conventional trans-esterification. Castor oil bean seed contains between 35 and 55% oil and does not compete with food grade oil because of the seed’s toxicity. This study evaluated the effect of temperature and percentage of initial catalyst on yield of castor ethyl ester. Raw castor oil bean seed kernel at moisture content of 4.68 % (db) was subjected to in-situ trans-esterification in a batch processor with ethanol as the solvent and sodium hydroxide as the catalyst. Central composite design (CCD) of the Response surface methodology was applied to evaluate the main and interactive effects of initial catalyst amount (0.5 – 1.5%) and reaction temperature (40 – 70OC), on yield of castor ethyl-ester, at reaction time of 120 minutes and alcohol-seed weight ratio of 1:1. A quadratic non-linear polynomial model was obtained to describe the effect of the factors on yield. The model was significant (P< 0.05) with a non- significant Lack-of-Fit value (P< 0.05) and R2 value of 0.944. Second order response surfaces and contour plots obtained from the model revealed that initial catalyst amount was the more effective factors on yield while reaction temperature had less effect. The Temperature–percentage of initial catalyst interaction was small and negative, due to the combined effects of formation of by-products (soaps) and saponification. The biodiesel produced from ground castor oil bean seed during this study met the requirements of ASTM standard D6751-02 but specific gravity was higher than the ASTM standard confirming that biodiesel produced from castor bean seed using the in-situ technique can be used as replacement fuel for fossil diesel

Optimization of in-situ Biodiesel Production from Raw Castor Oil-Bean Seed

Optimization of in-situ biodiesel production from raw castor oil-bean seed was carried out from raw castor bean oil seed (37.9% oil content) by alkaline catalyzed in-situ trans-esterification with Sodium hydroxide as catalyst and ethanol as the solvent in a laboratory batch processor. Response surface methodology and central composite experimental design was applied to evaluate effects of reaction time (30 -120 min), alcohol/seed weight ratio (0.5 – 2.0), Catalyst amount (0.3 – 1.5%) and reaction temperature (40 – 70OC). Catalyst amount, reaction temperature and time all had significant main effects (p < 0.05) while Alcohol-seed ratio had only slight effects on yield of castor biodiesel as a main effect but was significantly involved in interactions with other factors. A modified statistical model comprised of all significant factors and interactions (p < 0.05) obtained by multiple regressions predicted that the highest yield of castor ethyl-ester was 99.5% of expressible oil at the following optimized reaction values; alcohol/seed weight ratio of 0.5, a catalyst./seed weight ratio of 1.31, reaction temperature of 60.33oC, and reaction time of 81.7minutes. A Taguchi L9(3^4) optimization experimental design used to confirm the modified model at optimum point and two other points within experimental region produced yield that was significantly comparable to model predictions at 95% confidence level using a paired t-test. Measured properties of the castor ethyl-ester such as viscosity(5.78mm2 /s), pour point (-21.5 oC), flash point (177.12 oC), calorific value (47.76MJ/kg), acid value (0.34 mg KOH/g) and cetane number (48.73) were within the ASTM standard D6751-02 but specific gravity. Keywords: Castor oil-bean seed, biodiesel, in-situ trans-esterification, response surface methodology, optimization, Castor ethyl-este