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Indian Journal of Science and Technology Vol.2 No.10 (Oct 2009) ISSN: 0974- 6846

Performance and emission characteristics of a with castor Ch .S. Naga Prasad1 , K. Vijaya Kumar Reddy1, B.S.P. Kumar1, E. Ramjee1, O.D. Hebbel2 and M.C. Nivendgi2 1Dept. of Mech. Engg., JNTU College of Engg., Hyderabad-85; 2PDA College of Engg., Gulburga, Karnataka, . [email protected] Abstract: Bio-diesel is one of the most promising countries, alternate diesel fuel is the need of the hour. alternatives for diesel needs. Use of edible oil may create The idea of using vegetable as a fuel for diesel shortage of oil for daily food, which necessitates engines is not a new one. Rudolph Diesel used identification of new kinds of non-edible . to fuel in his engine at Paris Exposition of 1900.However, With this objective, the present work has focused on the despite the technical feasibility, vegetable oil as fuel could performance of castor non-edible vegetable oil and its not get acceptance, as they were more expensive than blend with diesel on a single cylinder, 4 stroke, naturally fuels. Later the various factors as stated aspirated, direct injection, water cooled, eddy current earlier, created renewed interest of researchers in dynamometer Kirloskar Diesel Engine at 1500 rpm for vegetable oil as substitute fuel for diesel engines. In variable loads. Initially, castor neat oil and their blends recent years systematic efforts have been made by were chosen. The physical and chemical properties of several researchers (Rakopoulos et al.,1992; Humke et Castor oil were determined. In general, of neat al.,1995; Barsic et al.,1996; Hemmer Lien et al.,1997; vegetable oil is high, which can be reduced through Michel et al., 1998; Vellguth et al.,1998; Reddy, 2000; blending with diesel and heating them. The heating Agarwal et al., 2001; Altin et al., 2001; Herchel et al., temperature of the blends increases with the increase in 2001; De Almedia et al., 2002) to use vegetable oils such the percentage of neat oils with diesel ranging from 700C as sunflower, , peanut oil, oil, to 1200C before entering into the combustion chamber. oil, bran oil, Jatropha, pongamia, etc. and The suitability of neat Castor oil and their blends are their derivatives, in the place of diesel in C.I. engines and evaluated through experimentation. The performance and proved useful as alternate fuel. As many of them are emission characteristics of engine are determined using edible, their usage may create shortage of oil seeds for Castor neat oil and their blends with diesel. These results daily food, which necessitates identification of new kinds are compared to those of pure diesel. These results are of non-edible vegetable oil. The recent upward trend in oil again compared to the other results of neat oils and their prices due to uncertainties in supply of petroleum blends available in the literature for validation. By products scarcity and ultimately depletion has a great analyzing the graphs, it was observed that the impact on Indian economy and the Nation has to look for performance characteristics are reduced and emission alternatives to sustain the growth rate. characteristics are increased at the rated load compared Testing of diesel engines with neat vegetable oils as to those of diesel. This is mainly due to lower calorific diesel blend over preheating improved the performance value, high viscosity and delayed combustion process. and reduced the emissions comparatively (Pramanik et From the critical analysis of graphs, it can be observed al., 2003, Ramdas et al., 2005). It also reduced the filter that 25% of neat Castor oil mixed with 75% of diesel is clogging and ensured smooth flow of oil. Some of the the best suited blend for Diesel engine without heating researchers (Hebbal et al., 2006; Choudhury et al., 2007) and without any engine modifications. It is concluded that conducted experiments on diesel engine using non-edible castor non-edible oil can be used as an alternate to vegetable oil as alternate fuels and found maximum diesel, which is of low cost. This usage of neat bio-diesel brake thermal efficiency and BSFC. The uses of has a great impact in reducing the dependency of India (Avinash Kumar Agarwal et al., 2008) in conventional on oil imports. diesel engines resulted substantial reduction in emission Keywords: Castor oil, alternate fuel, biofuel, emissions, of unburned hydrocarbons, carbon monoxide and non edible oils, performance characteristics. particulate. The neat biodiesel can be converted into Introduction methyl esters of biodiesel using transestrification process. The consumption of diesel fuels in India was 28.30 Methyl and ethyl esters of Karanja oil (Baiju et al., 2009) million tones which was 43.2% of the consumption of can also be used as a fuel in compression ignition engine petroleum products. This requirement was met by without any engine modification. importing crude petroleum as well as petroleum products. From above stated factors it is evident that The import bill on these items was 17,838 crores. With identification and testing of new non edible oils on diesel the expected growth rate of diesel consumption of engine is of great importance. In the present investigation more than 14% per annum, shrinking crude oil reserves Castor oil, non-edible vegetable oil is selected for the test and limited refining capacity, India will be heavily and its suitability as an alternate fuel is examined. This is dependent on imports of crude petroleum and accomplished by blending of Castor oil with diesel in petroleum products. 25/75%, 50/50%, 75/25%, 100/0% on volume basis; From the standpoint of preserving the global further these blends are heated to reduce viscosity equal environment and to sustain from the large imports of to that of diesel. Then the following investigations are crude petroleum & petroleum products from Gulf carried out: Research article “Characteristics of castor oil as biofuel” Naga Prasad et al. Indian Society for Education and Environment (iSee) http://www.indjst.org Indian J.Sci.Technol. 26

Indian Journal of Science and Technology Vol.2 No.10 (Oct 2009) ISSN: 0974- 6846

• The effect of blending Castor oil with diesel on containing 75% of diesel has density and viscosity close viscosity. to that of diesel. • The effect of temperature on viscosity of various Castor Effect of temperature on viscosity of caster oil and diesel oil and diesel blends and the temperature at which the blends Fig.2 shows the variation of viscosity of blends with F temperature. The Fig.1. Layout of experimental setup with viscosity of blends Control instrumentation deceases with Compter Panel F increase in temperature. Blend containing 75 % diesel have viscosity T4 EGA SM PT close to diesel at T2 T5 T6 300C and does not Calorimeter require heating. Table 1. Comparison of properties of T3 castor oil with diesel oil Property Diesel oil Castor oil Density (g/ml) 0.84 0.956 0 Engine Rota at 30 C Calorific value 42000 36000 N Dynamo meter (kj/kg) T1 Viscosity (cst) 5.0 78 at 300C Flash point 57 320 (0C) 0 viscosity of blends equal to Fire point ( C) 65 345 that of diesel at 300C. Table 2. Properties of castor oil – diesel blends However blends containing Casto Diesel Density Viscosity Viscosity in 50%,25%,0% diesel requires • The performance and 0 r oil oil (g/cc) at (cst) at reduction heating up to 70,80,95 C emission characteristics of 0 0 (%) (%) 30 C 30 C (%) respectively before firing into diesel engine using various 100 0 0.956 78 - combustion chamber to attain blends and compare the 75 25 0.925 62 20.5 viscosity equivalent to that of results with that of diesel. 50 50 0.893 45 42.3 0 diesel at 30 C . • Further for ascertaining the 25 75 0.862 25 67.9 0 100 0.840 5 93.58 Experimental test rig- validity of the results obtained, instrumentation the performance and emission characteristics of neat This investigation was conducted on a single cylinder, Castor oil are compared with the results available in the 4 stroke, water cooled, stationary Kirloskar diesel engine literature for similar work. computerized test rig with the Rated power 5.2 kW/7 hp Characterization of castor oil @ 1500rpm. The Kirloskar engine is one of the widely Properties of Castor oil used engines in agriculture tractors, pump sets, arm Castor oil is non-volatile fatty oil taken from beans of machinery, Transport vehicles, small and medium scale the plants. It ranges in color from colorless to greenish. It commercial purposes. The engine can withstand the peak has two derivatives such as blown castor and pressure encountered because of its high compression hydrogenated oil. Castor oil used in textiles, , ratio. The specifications of test rig are given in Table 3. varnishes, , , fibers, hair oils and drying Engine was directly coupled to an eddy current oils. It is also used for traditional and medical treatment dynamometer. The engine and dynamometer were purposes. Table 1 shows the comparison of properties of interfaced to a control panel, which is connected to a castor oil with diesel. computer. This computerized test rig was used for Effect of dilution on viscosity of castor oil and diesel recording the test parameters such as fuel flow rate, blends temperatures, air flow rate, load etc. and for calculating and diesel are blended in 0/100%, the engine performance characteristics such as brake 25/75%, 50/50%,75/25%,100/0% on volume basis and thermal efficiency, brakes specific fuel consumption, the mixture is stirred well to get homogenous stable volumetric efficiency etc., the calorific value and the mixture .Variation of density, viscosity, and percentage 0 density of a particular fuel was fed to the software as reduction in viscosity of blends at 30 C are shown in input variables. Planet Equipment of 5 gas analyzer is Table 2. The density and viscosity of blends reduces with used to find out the emission characteristics like carbon increases in percentage of diesel in blend. The blend Research article “Characteristics of castor oil as biofuel” Naga Prasad et al. Indian Society for Education and Environment (iSee) http://www.indjst.org Indian J.Sci.Technol. 27

Indian Journal of Science and Technology Vol.2 No.10 (Oct 2009) ISSN: 0974- 6846

monoxide (CO), carbon Table 3. Experimental setup specifications & T6: Exhaust Gas Engine Type Four stroke, single cylinder dioxide (CO2), un-burnt hydro Temperature before and after carbons (UHC), nitrogen oxides constant speed, water cooled Calorimeter (0C); F1: Fuel Flow (NO), unused oxygen (O ). diesel engine, Eddy current DP (Differential Pressure) unit; 2 Dynamometer Smoke measurement is made F2: Air Intake DP Unit; PT: Rated power 5.2 kW/7 hp @ 1500rpm using an OPAX2000II/DX200P Cylinder bore 87.5 mm Pressure Transducer; Wt: meter of Neptune Equipments. Cylinder stroke 110 mm Load; N: RPM Decoder; EGA: The layout of experimental test Compression Ratio 17.5:1 Exhaust Gas Analyzer (5 rig and instrumentation is Dynamometer 185 mm Gases); SM: Smoke Meter; shown in Fig.1. arm length CaO: Castor Oil; CaO (N): Neat Variable load Fig.2. Variation of viscosity of blends in relation to temperature Castor Oil; D: Diesel; tests are conducted CS (N): Neat Cotton for 0.2, 1, 2, 3, 4, Oil; RB(N): Neat 5.2 KW at a ; BHP: constant rated Brake Horse Power; speed of 1500 rpm, E.T: Exhaust 200 bar injector Temperature; NOx: opening pressure. Nitrogen Oxides; UHC: The Linseed oil and Un-burnt Hydro its blends with Carbons; CO: Carbon diesel are heated Monoxide; BSFC: externally as stated Brake Specific Fuel earlier before Consumption. injecting into the Results and discussion test cylinder. The Experimental engine was investigations are sufficiently warmed carried out on a up and stabilizes single cylinder DI before taking all diesel engine to readings. All the examine the observations are suitability of castor replicated thrice to oil as an alternate get a reasonable fuel. Firstly, the value. The effect of dilution performance with diesel and characteristics of Fig.3. Variation of brake thermal efficiency with brake heating of blends the is evaluated in power for castor oil and its blends on viscosity were terms of Brake studied. Then the Thermal Efficiency performance and (ηth), Brake the emission Specific Fuel Consumption (BSFC) and exhaust gas characteristics of blends are evaluated and compared temperature (E.T) and the emission characteristics in with diesel and optimum blend is determined. Further for terms of CO, UHC, NO and smoke opacity. These the confirming its validity the results are compared with performance and that of neat cotton emission seed and neat rice characteristics are bran oil available in compared with the the literature for results of baseline similar work. diesel. Performance Nomenclature: T1, characteristics T3: Inlet water Fig.4. Variation of brake specific fuel Fig.3 shows the temperature (0C); T2: consumption with brake power for castor oil and variation of brake Outlet engine Jacket its blends thermal efficiency Water Temperature (BTE) with brake (0C); T4: Outlet power output for Calorimeter Water castor oil and its Temperature (0C); T5 blends with diesel Research article “Characteristics of castor oil as biofuel” Naga Prasad et al. Indian Society for Education and Environment (iSee) http://www.indjst.org Indian J.Sci.Technol. 28

Indian Journal of Science and Technology Vol.2 No.10 (Oct 2009) ISSN: 0974- 6846 in the test engine. compared with all BTE of 25% blend other blends and of castor oil diesel. CO of neat compared well with castor oil has the diesel and exhibited highest value at the highest value at full load. The 76.92% of total highest value of load. The maximum CO at 25% blend BTE at 25% blend of castor oil is of castor oil is Fig.5. Variation of exhaust temperature with 2.12% in respect 33.20% obtained at brake power for castor oil and its blends to the value of 4 Kw against the 1.95% for diesel. 34.1%, for diesel. While at the Fig.4 shows the maximum BTE variation of brake specific load of neat castor fuel consumption with oil it is 0.48% brake power output for corresponding to castor oil and its blends diesel of 0.22%. with diesel in the test Fig.7 shows engine. Diesel has lower Fig.6. Variation of carbon monoxide with the variation of un- bsfc value compared with brake power for castor oil and its blends burnt hydrocarbons all other blends, whereas emissions with 25% blend of castor oil has brake power output lower bsfc values. The for castor oil and its lowest bsfc of neat castor blends with diesel oil is 0.305 Kg/Kw- hr, in the test engine. whereas it is 0.210 Kg/Kw- UHC of 25% blend hr for diesel. At the maximum of castor oil has thermal efficiency load of 25% Fig.7. Variation of un-burnt hydro carbons with lower emissions blend, the bsfc of castor oil is brake power for castor oil and its blends compared with all 0.320 Kg/Kw- hr, corresponding other blends. to the 0.251 value for diesel. While, UHC of 50% Fig.5 shows the variation of and 75% blends of Exhaust Temperature (E.T) with castor oil brake power output for castor oil compared well. and its blends with diesel in the The maximum test engine. The E.T of 25% value of UHC at blend of castor oil has lower 25% blend of values compared with all other castor oil is 79 blends and is well comparable ppm, with diesel. The E.T of all blends corresponding to and diesel increases with diesel is 74 ppm. increase of operating loads. The 25% blend of castor oil Fig.8 shows the variation of nitrogen oxides has higher performance than other blends due to emissions with brake power output for castor oil and its reduction in exhaust blends with diesel loss. in the test engine. Emission NOx of 25% blend characteristics of castor oil is Fig.6 shows the slightly lower than variation of smoke that of diesel. emissions with brake Diesel has higher power output for castor NOx emissions oil and its blends with compared with all diesel in the test Fig. 8. Variation of nitrogen oxides with brake other blends engine. CO emissions power for castor oil and its blends throughout all of 25% blend having operating loads. higher values NOx emissions of Research article “Characteristics of castor oil as biofuel” Naga Prasad et al. Indian Society for Education and Environment (iSee) http://www.indjst.org Indian J.Sci.Technol. 29

Indian Journal of Science and Technology Vol.2 No.10 (Oct 2009) ISSN: 0974- 6846 neat castor oil has maximum value at 76.92% of rated consumption, exhaust temperature, smoke, un-burnt loads and exhibited lower emission rate compared with all hydrocarbons, CO and NOx emissions. other blends at all load. The maximum NOx emission for Nag raja et al. (2005) also conducted the variable 25% blend of castor oil is 55 ppm, while for diesel it is load test at fuel injection pressure of 200 bar and constant cooling water outlet temperature of 650C. Performance of engine is evaluated only in terms of BTE, brake specific fuel consumption, and exhaust temperature. Through the performance results are available for blends, for convenience only results of neat vegetable oils are used for comparison. For this Fig.9. Variation of smoke with brake purpose of comparison cotton used by power for castor oil and its blends Leenus Jesu Martin et al. is labeled as (100% CS) and rice bran of Nag raja et al. as (100% RB). Fig.10 to 12 shows the variation of BTE, BSFC and E.T of neat castor oil (100% CaO), 100% CS and (00% RB with brake power. The BTE of castor oil is lower than that of 100% RB for entire operating 58ppm. load. The maximum BTE of 100% CaO, 100% CS and Fig.9 shows the variation of smoke emissions with 100% RB are 22.30%, 29% and 30.10%, respectively. brake power output for castor oil and its blends with BSFC of castor oil is higher and BTE is lower compared diesel in the test engine. Diesel has lower smoke with 100% RB. This drop in performance must be emission compared with all other blends of castor oil. attributed to the higher exhaust temperature, which 25% blend of the castor oil smoke opacity is well accelerates the loss due to incomplete combustion, there comparable with diesel. Smoke of neat castor oil has by increases the emissions. highest values compared with all other blends and diesel. Fig.13 to 16 shows the variation of CO, UHC, NOx The maximum smoke at 25% blend of castor oil is 4.56 and smoke emissions of 100% CaO, 100% CS and 100% Bosch Smoke units, corresponding to diesel is 4.15. RB with brake power. UHC and NOx emissions of Castor oil are lower compare with 100% CS and 100% RB for entire operating load. The smoke emissions also lower compared with 100% CS for entire operating except at full load. The CO emissions

Fig.10. Variation of brake thermal efficiency with brake power for neat castor oil, neat cotton seed oil Fig.11. Variation of brake specific fuel consumption and neat rice bran oil with brake power for neat castor oil, neat and neat rice bran oil Comparison of castor oil (CaO) performance with cotton seed oil (CS) and rice bran (RB) oil To ascertain the validity of the results obtained from CaO, its performance is compared with results obtained by similar experimental work reported earlier (Leenus of castor oil at full load are 4.25 % which is higher at full Jesu Martin et al., 2005; Nag raja et al., 2005). Wherein load compared with other oils. the viscosity of vegetable oil is reduced by dilution with From above discussion it is clear that performance diesel and further, blends are to be heated at room and emission characteristics of castor oil are better than temperature. They have also used the similar 5.2Kw/7hp, that of other oils (CS and RB) considered. 1500 rpm, naturally aspirated, water cooled, 4 stroke, Conclusion single cylinder, Kirloskar diesel engine, which further simplifies the process of comparison. • The properties like density, viscosity, flash point and Leenus Jesu Martin et al. (2005) conducted the fire point of castor oil (IS: 1448 [p:6],1994; IS: 1448 [p: variable load performance test with cotton seed oil at fuel 25],1976; IS: 1448 [p: 20], 1998) is higher and calorific injection pressure of 200 bars and constant cooling water value is 0.936 times that of diesel. outlet temperature of 750C. Then the performance of the • Dilution of castor oil reduces the viscosity considerably. engine is evaluated in terms of BTE, brake specific fuel The blend containing 75% of diesel has viscosity 15 cst Research article “Characteristics of castor oil as biofuel” Naga Prasad et al. Indian Society for Education and Environment (iSee) http://www.indjst.org Indian J.Sci.Technol. 30

Indian Journal of Science and Technology Vol.2 No.10 (Oct 2009) ISSN: 0974- 6846

close to viscosity of diesel at 300C and does not require • Performance of the castor oil is validated as results are any heating prior to injection into combustion chamber. well comparable with the results of cotton seed oil and Blends containing 50%, 25%, and 0% diesel require rice bran oils. preheating up to 70, 80 and 950C respectively. Hence from above conclusions it may be stated that • The performance and emission characteristics of 25% blends up to 25% without preheating and up to 50% with blend of castor is better than that of all other blends and preheating can be substituted as fuel for diesel engine it is well comparable with diesel. without any modifications in the engine. • However at rated load, the neat castor oil emissions viz. Acknowledgments CO, UHC, smoke are 56.41%, 20.27%,31.32% The author sincerely thanks Dr. O.D.Hebbel, respectively higher and NOx are 44% lower compared Assistant Professor and M.C.Nivendgi, Selection Grade to those of diesel. This is due to incomplete Lecturer and their organization- PDA college of combustion of the fuel and delay in the ignition process. Engineering, Gulbarga, for support, co-operation, and • The Brake Thermal Efficiency (BTE), BSFC of castor oil encouragement to get the permission and to conduct the are 33.45% lower and 54.76% higher compared to experimental work in IC engines. those of diesel. This is due to higher viscosity and lower References calorific value of the fuel. 1. Agarwal AK and Das LM (2001) Bio diesel development and characterization for use as fuel in Fig.12. Variation of exhaust temperature with brake power for compression engines. Trans. ASME. 123, 440- neat castor oil, neat cotton seed oil and neat rice bran oil 447. 2. Altin R, Cetinkaya S and Yuces HS (2001) The potential of using vegetable oil fuel as fuel in compression Ignition engines. Energy Conversion Mangt. 42, 529-538. 3. Avinash Kumar Agarwal (2007) Biofuels (alcohols and biodiesel) applications as fuels for internal combustion engines. Prog. in Energy & Combustion Sci., 33, 233–271. 4. Baiju B, Naik MK and Das LM (2009) A comparative evaluation of compression ignition engine characteristics using methyl and ethyl esters of Karanja oil. Renewable Energy. 34, 1616–1621. • The maximum BTE of castor oil is obtained at 76.92% 5. Bari S, Lim Th and YU CW (2002) Effects of of the total load. i.e., 4 Kw load. The emissions like CO, preheating of crude (CPO) on injection system, UHC, smoke and NOx for 25% blend of castor oil is performance and emission of a diesel engine. higher by 145%, 41.17%, 48% and lower by 31.03%, Renewable Energy. 27, 339-351. respectively compared to that of diesel. This is due to 6. Barsic NJ and Humke AL (1996) Performance and incomplete combustion of the fuel (or) Lean air-fuel emissions characteristics of a naturally aspirated diesel engine with vegetable oil fuels. SAE paper No.810262. Fig.13. Variation of carbon monoxide with brake power for neat 7. Choudhury S and Bose PK (2007) Karanja castor oil, neat cotton seed oil and neat rice bran oil or Jatropha– a better option for an alternative fuel in CI engine. In: Intl. Conf. on IC Engines (ICONICE), Hyderabad. 8. De Almedia SCA, Belchior CR, Nascimento MVG, Vieira LSR and Flueury G (2002) Performance of a diesel generator fuelled with palm oil. Fuel. 81, 2097-2102. 9. Ertan Alptekin and Mustafa Canakci(2006) Determination of the density and the of biodiesel– diesel fuel blends. Renewable Energy (33), 2623– 2630. 10. Hebbal OD, Vijaya Kumar Reddy K and Rajagopal K (2006) Performance characteristics of a diesel engine with Deccan . Fuel.(42), 45 - 52 . 11. Hemmer Lien N, Korte V and Richter H mixture formation. (1997) Performance, exhaust emissions and durability of modern diesel engines running on rapeseed oil. SAE paper No.910848.

Research article “Characteristics of castor oil as biofuel” Naga Prasad et al. Indian Society for Education and Environment (iSee) http://www.indjst.org Indian J.Sci.Technol. 31

Indian Journal of Science and Technology Vol.2 No.10 (Oct 2009) ISSN: 0974- 6846

12. Henham AWE (1990) Experience with alternate fuels viscosity, Bureau of Indian Standards. New Delhi. p:25. for small stationary diesel engines: fuels for automotive 17. IS: 1448 (1984) Methods of test for petroleum and its and industrial diesel engines., I. Mech. E.(46) 117-22. products: heat of combustion of liquid hydrocarbon fuels 13. Herchel TCM, Seiichi S, Takao K and Hisao N (2001) by bomb calorimeter method. Bureau of Indian Performance and emission characteristics of a diesel Standards. New Delhi. p:6. engine fueled with coconut oil –diesel fuel blend. 18. IS: 1448 (1998) Methods of test for petroleum and its Biomass Bioenergy. 20, 63-69. products: Determination of flash point and fire point by Fig. 14. Variation of un-burnt hydro carbons with brake power for Able’s apparatus, Bureau of Indian Standards. neat castor oil, neat cotton seed oil and neat rice bran oil New Delhi. p:20. 19. Kalam MA and Masjuki HH (2004) Emission and deposit characteristics of a small diesel engine when operated on preheated crude palm oil. Biomass Bioenergy. 27, 289-297. 20. Leenus Jesu Martin M, Prithviraj D, Chandrasekaran S and Tamilporai P (2005) Effect of cotton seed oil and diesel blends on the performance and emission of a compression ignition engine. In: Proc. of 19th Natl. Conf. on I.C. engines and combustion, Annamalai Univ. pp: 101-105. 21. Michel SG and Robert LM (1998) Combustion of and vegetables oil derived fuels in diesel 14. Humke AL and Barsic NJ (1995) Performance and engines. Prog. Energy. Combustion Sci. 24,125-64. emission characteristics of naturally aspirated diesel 22. Nag raja AM and Prabhu Kumar GP(2005) engine with vegetable oil fuels– part 2: SAE paper Performance of diesel, neat biodiesel and 20% biodiesel – a comparative study. In: Proc. of 19th Natl. Conf. on I.C. engines and combustion, Annamalai Univ. pp: 503-508. 23. Nwafor OMI (2004) Emission characteristics of a diesel engine running on vegetable oil with elevated fuel inlet temperature. Biomass Bioenergy. 29, 727-742. 24. Pramanik K(2003), Properties and use of Jatropha curcus oil and diesel fuel blends in Fig. 15. Variation of nitrogen oxides with brake power for compression ignition engines. Renewable neat castor oil, neat cotton seed oil and neat rice bran oil Energy. 28, 239-248. 25. Rakopoulos CD (1992) as a fuel supplement in DI and IDI diesel engines. Energy. No.810955. 17(8),787-790. 15. Huzayyin AS, Bawady AH, Rady MA and Dawood A 26. Ramdas AS, Jayaraj S and Muraleedhran C (2005) (2004) Experimental evaluation of diesel engine Characterization and effects of using rubber seed oil as performance and emission using blends of and fuel in compression ignition engines. Renewable diesel fuel. Energy Conversion Manager. 45, 2093 - Energy. 30, 795-803. 2112. 27 Rao PS and Gopalakrishna KV (1989) Use of non 16. IS: 1448 (1976) Methods of test for petroleum and its edible vegetable oils as diesel engine fuels. J. Intt products: Determination of kinematics and dynamic .Engg. India. 70 (4), 24-29. 28 Reddy KV (2000) Experimental investigations on Fig.16. Variation of smoke with brake power for the use of vegetable oil fuels in a four stroke, neat castor oil, neat cotton seed oil and neat rice single cylinder diesel engines. PhD Thesis. JNTU bil College of Engg., Anantapur, Andhrapradesh, India. 29 Vellguth G (1998) Performance of vegetable oils and their monoesters as fuels for diesel engines. SAE paper No.831358.

Research article “Characteristics of castor oil as biofuel” Naga Prasad et al. Indian Society for Education and Environment (iSee) http://www.indjst.org Indian J.Sci.Technol.