Feasibility of blending karanja vegetable oil in petro-diesel and utilization in a direct injection diesel engine

Karanja (Pongamia pinnata) oil, a non-edible high viscosity (27.84 cSt at 40 °C) straight vegetable oil, was blended with conventional diesel in various proportions to evaluate the performance and emission characteristics of a single cylinder direct injection constant speed diesel engine. Diesel and karanja oil fuel blends (5%, 10%, 15%, and 20%) were used to conduct short-term engine performance and emission tests at varying loads (0%, 20%, 40%, 60%, 80%, and 100%). Tests were carried out over the entire range of engine operation and engine performance parameters such as fuel consumption, thermal efficiency, exhaust gas temperature, and exhaust emissions (smoke, CO, CO₂, HC, NO_x, and O₂) were recorded. The brake specific energy consumption (BSEC), brake thermal efficiency (BTE), and exhaust emissions were evaluated to determine the optimum fuel blend. Higher BSEC was observed at full load for neat petro-diesel. A fuel blend of 10% karanja oil (KVO10) showed higher BTE at a 60% load. Similarly, the overall emission characteristics were found to be best for the case of KVO10 over the entire range of engine operation.     

Eco-Friendly Adhesives Based on Tannin and N,N-Bis(2-Hydroxy-Ethyl) Fatty Amides (HEFAs) from Non-Traditional Oils for Wood Bonding

Abstract

Wood adhesives were formulated using tannin and N,N-bis(2-hydroxyethyl) fatty amides (HEFAs). The natural tannin-based adhesives can be used to replace formaldehyde-based adhesive systems and thereby reduce formaldehyde and volatile organic compound (VOC) emissions from adhesives used for plywoods. Performance properties of the adhesively bonded wood joints viz., tensile strength, impact strength and chemical resistance were measured. N,N-bis(2-hydroxyethyl) fatty amides (HEFAs) from non-traditional oils were mixed with a pure tannin-based adhesive as a crosslinker, and this increased the tensile strength, impact strength and chemical resistance of wood joints. The results revealed that a high performance and eco-friendly adhesive system for wood can be successfully formulated using tannin and HEFA.     

Combustion analysis of Jatropha, Karanja and Polanga based biodiesel as fuel in a diesel engine

Non-edible filtered Jatropha (Jatropha curcas), Karanja (Pongamia pinnata) and Polanga (Calophyllum inophyllum) oil based mono esters (biodiesel) produced and blended with diesel were tested for their use as substitute fuels of diesel engines. The major objective of the present investigations was to experimentally access the practical applications of biodiesel in a single cylinder diesel engine used in generating sets and the agricultural applications in India. Diesel; neat biodiesel from Jatropha, Karanja and Polanga; and their blends (20 and 50 by v%) were used for conducting combustion tests at varying loads (0, 50 and 100%). The engine combustion parameters such as peak pressure, time of occurrence of peak pressure, heat release rate and ignition delay were computed. Combustion analysis revealed that neat Polanga biodiesel that results in maximum peak cylinder pressure was the optimum fuel blend as far as the peak cylinder pressure was concerned. The ignition delays were consistently shorter for neat Jatropha biodiesel, varying between 5.9^° and 4.2^° crank angles lower than diesel with the difference increasing with the load. Similarly, ignition delays were shorter for neat Karanja and Polanga biodiesel when compared with diesel.     

Comparative performance analysis of diesel engine fuelled with hydrogen enriched edible and non-edible biodiesel

In the present study, a comparative analysis of enrichment of hydrogen alongside diesel fuel and two different sources of biodiesel namely rice bran oil is an edible oil, and karanja oil being non-edible is tested. Hydrogen at a fixed flow rate of 7 lpm is inducted through the intake manifold. A total of six fuel samples are considered: diesel (D), hydrogen-enriched diesel (D + H₂), hydrogen-enriched 10, and 20% rice bran biodiesel blend (RB10 + H₂ and RB20 + H₂), and hydrogen-enriched 10 and 20% karanja biodiesel blend (KB10 + H₂ and KB20 + H₂). Results indicate that enrichment of hydrogen improves combustion and results in 2.5% and 1.6% increase in the brake thermal efficiency of diesel fuel and rice bran biodiesel, respectively. For karanja biodiesel the increment is negligible. Fuel consumption of the D + H? is 6.35% lower and for RB10 + H? and KB10 + H? it is decreased by 2.9% and 1.3%, respectively. The Presence of hydrogen shows the 4–38% lower CO emissions and 6–14% lower UHC emission due to better combustion. The blends RB10 + H? and KB10 + H? produce up to 6–13% higher NOx emission and that for the blends RB20 + H? and KB20 + H? it goes up to 25%. Overall rice bran oil is found to provide better performance than karanja biodiesel.     

Optimization of two step karanja biodiesel synthesis under microwave irradiation

The free fatty acid of crude karanja oil (Pongamia pinnata) was reduced and biodiesel was synthesized from pretreated oil under microwave irradiation. The process variables such as irradiation time, methanol-oil ratio and sulfuric acid concentration for pretreatment step; irradiation time, methanol-oil ratio and KOH concentration were optimized through the Box-Behnken experimental design. The free fatty acid of crude karanja oil was reduced to 1.11 ± 0.07% with an optimal combination of 190 s irradiation time (180 W), 33.83 (w/w)% methanol-oil ratio and 3.73 (w/w)% sulfuric acid concentration. An optimal combination of 150 s irradiation time, 33.4 (w/w)% methanol-oil ratio and 1.33 (w/w)% KOH concentration yielded 89.9 ± 0.3% biodiesel. The model was validated by conducting experiments at optimal design conditions. The present work confirmed that the microwave energy has a significant effect on esterification and transesterification reaction.     

Protease inhibitors and in vitro digestibility of karanja (Pongamia glabra) oil seed residue. A comparative study of various treatments

Trypsin and chymotrypsin inhibitor activities (TIA and CIA) were assayed before and after processing of Karanja oil seed residue. Upon treatment, the loss of TIA and CIA varied with the type of processing or extraction: the reduction after solvent extraction ranged between 34 and 15%, respectively. These activities were completely removed in 2.4% HCl; 83.35 and 54.86% were removed on autoclaving; 33.86 and 15.30% on fermentation; and removal was 4.36–83.69% and 3.66–77.59% after exposure to different doses of gamma radiation (1, 5, 10, and 50 KGy). An in vitro digestibility study was carried out to confirm the inactivation of the inhibitors and showed improvements from 45 to 81%, with the maximum observed in 2.4% HCl solvent-refluxed residue. A linear relationship was observed between the reduction in protease inhibitor activities and the improvement in digestibility.     

Long-term storage stability of biodiesel produced from Karanja oil

Biodiesel is an alternative diesel fuel made from vegetable oil or animal fat. It is more susceptible to oxidation or autoxidation during long-term storage than conventional petrodiesel. Karanja oil methyl ester (KOME) was prepared and stored for a period of 180 days under different storage conditions. The physicochemical parameters, peroxide value (PV) and viscosity (v) of samples were measured at regular interval of time under different storage conditions. The stability of Karanja oil methyl ester (KOME) was studied under different storage conditions. The stability of KOME was improved by adding different antioxidants Tert-Butylated Hydroxy toluene (BHT), Tert-Butylated Hydroxyanisole (BHA), Pyrogallol (PY), Propyl galate (PrG) and Tert-Butyl Hydroxyl Quinone (TBHQ). The effectiveness of three antioxidants BHT, BHA and PrG on Karanja oil methyl ester was examined at varying loading level during the storage period.     

Experimental investigations of performance and emissions of Karanja oil and its blends in a single cylinder agricultural diesel engine

An experimental investigation has been carried out to analyze the performance and emission characteristics of a compression ignition engine fuelled with Karanja oil and its blends (10%, 20%, 50% and 75%) vis-a-vis mineral diesel. The effect of temperature on the viscosity of Karanja oil has also been investigated. Fuel preheating in the experiments – for reducing viscosity of Karanja oil and blends has been done by a specially designed heat exchanger, which utilizes waste heat from exhaust gases. A series of engine tests, with and without preheating/pre-conditioning have been conducted using each of the above fuel blends for comparative performance evaluation. The performance parameters evaluated include thermal efficiency, brake specific fuel consumption (BSFC), brake specific energy consumption (BSEC), and exhaust gas temperature whereas exhaust emissions include mass emissions of CO, HC, NO and smoke opacity. These parameters were evaluated in a single cylinder compression ignition engine typically used in agriculture sector of developing countries. The results of the experiment in each case were compared with baseline data of mineral diesel. Significant improvements have been observed in the performance parameters of the engine as well as exhaust emissions, when lower blends of Karanja oil were used with preheating and also without preheating. The gaseous emission of oxide of nitrogen from all blends with and with out preheating are lower than mineral diesel at all engine loads. Karanja oil blends with diesel (up to 50% v/v) without preheating as well as with preheating can replace diesel for operating the CI engines giving lower emissions and improved engine performance.     

Partial hydrogenation and hydrogen induction: A comparative study with B20 operation in a turbocharged CRDI diesel engine

Numerous studies explored the possibility and effective strategies for supplementing hydrogen along with fossil or biofuels on internal combustion engines. Hydrogen is also being employed for formulating fuels such as hydrogen compressed natural gas in the gaseous form and hydrogenated biofuels in the liquid form. The present study evaluates (i) hydrogen usage on the fuel formulation and (ii) investigates the engine operation of an automotive turbocharged diesel engine operated with karanja biodiesel blended diesel (B20) as a reference fuel. Existing literature outlines that biodiesel blends possess lower energy content and emit higher nitric oxide (NO) emission than fossil diesel. The present research paper partially hydrogenates karanja biodiesel using an autoclave reactor with a palladium catalyst to increase the saturation levels and mitigate the biodiesel-NO penalty. Besides, the drop in energy release of B20 is compensated through the provision of hydrogen induction along the intake manifold. The hydrogen flow rates to the turbocharged engine are maintained at a fixed energy share of 10%. Both biodiesel and hydrogenated biodiesel were blended on a volume basis (20%) with fossil diesel (80%) and are designated as B20 and HB20, respectively. The test results reveal that HB20 effectively mitigates the biodiesel-NO penalty with a maximum reduction of 29.8% compared to B20. Further, hydrogen induction yielded a significant improvement (23.7%) in fuel consumption with HB20 relative to B20 without hydrogen addition. The compounding effect of hydrogen usage on the engine operation and fuel formulation exhibited a better performance and emission trade-off at mid load conditions.