الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Energy consumption is escalating day by day because of raising population and rapid economic growth rate. Extensive use of petroleum-based fuels results in emissions of highly complex mixtures which causes potential impact to human health and environmental pollution leading to global warming and also decrease in energy reserve. The Biodiesel has been one of the main alternate energy resources to substitute petroleum-based fuel, owing to its attractive properties as emissions reduction, sustainability, and renewability. So the aims of this study to evaluate the biodiesel produced from the oil of some energy plants and to evaluate the efficiency of the purification methods and the effect of the different blended ratios of biodiesel with petroleum diesel on the performance of the engine and the resulting emissions.
The research was conducted at the Biofuel Laboratory of the Tractor Research and Test Station of the Agricultural Engineering Research Institute. Biodiesel was produced from extracted non edible oils of both Jatropha and Pongamia plant seeds by transesterification process by heating oil at 60 ° C and mixing with methanol in a volume ratio of (methyl alcohol to oil) 1: 5 in presence of a catalyst (potassium hydroxide) and stirring then leaving the mixture. To separate biodiesel from glycerol (as a byproduct of the reaction), the impurities in the biodiesel (methanol - water content - glycerol - soap content) were measured before and after the biodiesel purification process.
The purification was carried out in three ways, firstly wet washing (with water) - secondly dry washing (with sawdust) - thirdly dual washing (first washing with water and then with sawdust) and comparing them with the American standard specifications and determining the efficiency of the different purification methods, also measuring the physical properties of petroleum diesel (B0), biodiesel 100% (B100) and biodiesel blended with diesel by 10% (B10), 20% (B20), and 30% (B30) and the biodiesel blend effect on the engine performance and emision profile.
Results revealed that statistically significant difference at p ≤ 0.05 between the biodiesel yield of Jatropha (91.67 ± 1.53) and biodiesel yield of Pongamia (86.0 ± 2.65) in the same production process condition. The results of the statistical analysis between the used purification methods indicated a statistically significant difference at p ≤ 0.05 among dry purification method of biodiesel (with sawdust) and the water purification method (wet washing) in the case of methanol, as well as the presence of a statistically significant difference between the three methods used for purification (wet, dry, and dual washing) in the case of water content. While in case of glycerol and soap content there is no statistically significant difference between the three purification methods. The study also showed that the purification of biodiesel with sawdust (dry washing) is more efficient in removing both methanol (98.3%) and water content (96.6%) than other purification methods (wet washing and dual washing), while all the purification methods in case of glycerol and soap content were of similar efficiency.
Also, some physical and chemical properties were estimated for each of the biodiesel alone (B100) and the biodiesel blended in percentage volumes (10%, 20%, and 30%) with petroleum diesel. By comparing the characteristics of the biodiesel belend (B10), (B20) and (B30) with petroleum diesel, the results showed that the biodiesel has nearly similar values with petroleum diesel in the case of density, calorific value and cetane number, while the values of the biodiesel blend in the case of viscosity, cloud point, and the flash point had higher values than petroleum diesel. The chemical and physical properties of biodiesel are found within acceptable limits of the American Standard Specifications (ASTM).
Biodiesel was tested at previous blended ratios and compared with petroleum diesel (B0). As engine power was measured at maximum load and the engine performance results showed that using biodiesel by 10%, 20% and 30%. was less by 2.8%, 5.8% and 8.7% respectively in the case of Jatropha, while in the case of Pongamia it was less by 4%, 6.7%, and 9.6 % respectively of the power compared to petroleum diesel fuel. While the specific fuel consumption increased by 8.6%, 16.9% and 19.1%, with a blended ratio 10%, 20%, and 30% respectively in the case of Jatropha, and in the case of Pongamia, it increased by 9.7%, 18% and 20.2% respectively compared to petroleum diesel.
The emissions of engine exhaust gases resulting from the use of biodiesel were compared and evaluated with the previous blended ratios by measuring (the temperature of exhaust gas - carbon monoxide gas - carbon dioxide gas - nitrogen oxides emissions) and compared them with the combustion gas emissions of petroleum diesel fuel. The results of the emissions by using biodiesel with blended ratio of 10, 20 and 30% indicated that the exhaust gas temperature decreased by 12.95%, 14.40% and 15.61% respectively in the case of Jatropha, while in the case of Pongamia it decreased by 11.46%, 13.41% and 14.63% respectively compared to the petroleum diesel fuel. The percentage of carbon monoxide decreased by 12.37%, 14.92% and 14.41% respectively in the case of Jatropha, while in the case of Pongamia it decreased by 12.71%, 15.25% and 14.75% respectively compared to the petroleum diesel and the percentage of carbon dioxide decreased by 0.1%, 0.4% and 0.5% respectively in the case of Jatropha, while in the case of Pongamia it decreased by 0.3%, 0.6% and 0.7%, while the percentage of nitrogen oxides increased by 0.57%, 1.14% and 2.84% respectively in the case of Jatropha, while in the case of Pongamia it increased by 1.14%, 2.27% and 5.11% respectively compared to petroleum diesel fuel.
The present study concluded that the dry washing process more favorable from the environmental perspective than other washing ones and recommended that using dry washing in biodiesel purification processes due to shorter purification time, no wastewater production, and smaller unit sizes that is save water and energy.
5.2 . Conclusion
Based on the findings of the study, the following can be concluded:
• The yield percent of biodiesel from Jatropha oil is higher than that of biodiesel from Pongamia oil under the same conditions of the transesterification reaction.
• Chemical and physical properties of the produced biodiesel from Jatropha and Pongamia oils are within the acceptable limits of the American Standard Specifications (ASTM).
• The method of biodiesel purification using sawdust (dry washing) is more efficient to get rid of methanol and water content than the other two purification methods (wet washing) and (dual washing); in the meantime, all the purification methods have similar efficiency in getting rid of glycerol and soap content.
• The chemical and physical properties of biodiesel blended in percentages of volume (10%, 20%, and 30%) with petroleum diesel have nearly similar values with petroleum diesel in the case of density, calorific value and cetane number, while the values of the biodiesel mixture in the case of viscosity, cloud point and Flash point had higher values than petroleum diesel.
• The use of blended ratios of 10, 20 and 30% of biodiesel with petroleum diesel led to limited reduction in engine power, as well as emissions of carbon monoxide and carbon dioxide gases and the exhaust gas temperature, while specific fuel consumption and nitrogen oxides have been increased at the different ratios.
• The cost of producing one ton of Jatropha biodiesel approximately 11723 LE/ton (11.72 L.E/kg of biodiesel) and the cost of producing one ton of Pongamia Biodiesel approximately 12496 LE/ton (12.5 L.E/kg of biodiesel)
5.3 . Recommendations
Based on the results of the study, the following was recommended:
• Highlighted and attention to bioenergy as a renewable source of energy to achieve sustainable development goals and Egypt’s Vision 2030
• Using non-edible oils as a renewable sources and friendly of environment for biodiesel production
• Using biodiesel blends with petroleum diesel in low ratios.
• Using dry washing in biodiesel purification processes, as it is faster, more efficient and less expensive than wet washing.