Effects of Biodiesel and Jatropha oil on Performance, Black Smoke and Durability of Single-Cylinder Diesel Engine

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1 Journal of Metals, Materials and Minerals. Vol.18 No.2 pp , 2008 Effects of Biodiesel and Jatropha oil on Performance, Black Smoke and Durability of Single-Cylinder Diesel Engine Teerapong BAITIANG *, Kiatkong SUWANNAKIT, Tanakorn DUANGMUKPANAO, Chamaiporn SUKJAMSRI, Subongkoj TOPAIBOUL and Nuwong CHOLLACOOP National Metal and Materials Technology Center (MTEC), 114 Thailand Science Park, Paholyothin Rd, Klong 1, Klong Luang, Pathumthani Thailand Abstract The aim of this research is to study the effects of neat biodiesel (B100) and pure jatropha oil on engine performance, black smoke density, fuel consumption and durability of engines. Two 14-horse power, single cylinder diesel engines were dedicated for the experiment using those fuels. From the performance test, when comparing BDF and jatropha oil with diesel, the engine performances were slightly different with a small increase of fuel consumption. It is noticeable that black smoke measured from the engines using both biodiesel and jatropha oil can be hugely reduced. However, in the case of field test when each engine was connected to power water pumps in order to determine the long term effects, the engine that was fueled with jatropha oil presented some problems. The injector and fuel filter were clogged enough to cause engine malfunction. The parts were then replaced and petroleum diesel fuel was added at an increment of 20% in the blended fuel to reduce the concentration of jatropha oil until the engine could run continuously again. It was found that the highest amount of jatropha oil could be used was a blend between jatropha oil and diesel fuel of 60:40 by volume for practical running time before failure. In the case of the engine using biodiesel, the field test could be performed without any engine problem for over 500 hours. The engine performance and black smoke after 300 hour field test was also measured for both Jatropha oil blend and biodiesel. All results are analyzed and discussed in this paper. Key words : Biodiesel, Jatropha oil, Single-cylinder diesel engine Received Nov. 25, 2008 Accepted Feb. 11, 2009 Introduction In Thailand, diesel is a crucial fuel to drive many sectors such as transportation, agriculture, industry and electricity. Among many other oilimporting countries, Thailand has spent a majority of the import bill on fossil oil, even greater than a total of main agricultural products export. The recent oil crisis has called upon an alternative source for diesel fuel. Straight vegetable oil and its biodiesel are viewed suitable for Thailand due to its agricultural economy, and can help alleviating the problem of under-price agricultural products. Thailand is blessed with many feedstock for biodiesel production such as palm, jatropha, coconut and sunflower. These crops can be used to produce biodiesel especially for usage in agriculture sector, in order to decrease the oil import and help stabilize the price of agricultural products. (3) In addition, biodiesel is an environmentally benign fuel since its oxygenated characteristic helps reducing greenhouse gas and other toxic emission. (4) In order to gain the farmers the confidence to use alternative fuel in their single-cylinder engines, a thorough investigation on engine performance, emission and durability is needed. The present investigation focuses on biodiesel of Thai standard (DOEB, 2007) and neat jatropha oil. Materials and Experimental Procedures Engine, Tested Fuels and Apparatus Two 14-hp single-cylinder engines were dedicated for jatropha oil and biodiesel, labeled as engine no. 1 and 2, respectively. Both jatropha oil and biodiesel were obtained from commercial sources. While jatropha oil was in a physically acceptable condition, biodiesel was conformed to Thai biodiesel standard (DOEB, 2007). Engine performance (power and torque) was measured via Phone x4630, Fax , teerapob@mtec.or.th

2 182 BAITIANG, T.et al. in-house apparatus, which uses electricity generator connecting to a series of halogen lamps as a load, as shown in Figure. 1(a). Volumetric fuel consumption was measured via timing the fixed amount of fuel consumed. Black smoke was measured by Tecnotest model 495/01 according to EEC method, as shown in Figure. 1(b). Durability test was conducted by connecting single-cylinder engine to water pump for close-loop water irrigation at 2,400 and 75% load, as shown in Figure. 1(c). (a) (b) No 1 No 2 (c) Figure. 1 Apparatus to measure (a) engine performance and fuel consumption, (b) black smoke, and (c) durability Table 1. Properties of various jatropha oil blends Methodology The 14-HP engines no. 1 and 2 are first tested for performance (power and torque), black smoke and fuel consumption using jatropha oil and biodiesel, respectively, with reference to petroleum diesel at 200 increment between 1,400 to 2,400. Then, both engines were connected to water pump for close-loop irrigation for over 300 hours. For engine no. 1 fueled with 100% jatropha oil, if the engine is malfunctioned, the degraded parts were replaced with the new tested fuel of 80% jatropha oil: 20% diesel. If this new fuel blend causes engine malfunction, similar step is repeated with 60% jatropha oil: 40% diesel, and so on. Otherwise, the engine was stopped at 300 hours for performance and emission benchmarking with the 0 hour results. Regular maintenance was followed according to manufacturer recommendation. Result and Discussion Tables 1 and 2 show the properties of jatropha oil blend and biodiesel, respectively. (2) In Table 1, the carbon residue in 100% jatropha oil is quite high (~10x diesel value), indicating potential problem to diesel injector. Higher blends with diesel help improving the cleanliness of the fuel and preventing injector clogging. Figure 1 compares the engine performance, fuel consumption and black smoke of engine fueled with jatropha oil and biodiesel. Overall, engine power and torque are not significantly different from diesel when the engines are fueled with jatropha oil or biodiesel. In comparison with diesel results, fuel consumption is slightly higher while black smoke is significantly improved. When both engines were put to durability test, engine no. 1 fueled with jatropha oil caused the engine to stop according to Table 3, as low as 18 hours for 100% jatropha oil. When the parts Properties Method Jatropha: Diesel blends JPO100 JPO80 JPO60 JPO40 JPO20 Diesel Carbon Residue (%wt) ASTM D Water Content (ppm) ASTM D Oxidation Stability (Hour) EN Acid Value (mg KOH/g) ASTM D Gross Heat (MJ/kg) ASTM D

3 Effects of Biodiesel and Jatropha oil on Performance, Black Smoke and Durability of Single-Cylinder Diesel Engine 183 were examined, all the malfunctioned cases reveal the injector clogging with a presence of gum at the coarse and fine filters. The 60% jatropha blended with 40% diesel yielded an acceptable usage time of over 140 hours. On the other hand, engine no. 2 fueled with 100% biodiesel could run without any malfunction for over 500 hours. Detailed parts examinations show some dirt at the injector but not enough to cause engine to stop. After 300 hours of being fueled with Jatropha oil blend and pure biodiesel, both engines were subjected to performance (power and torque), fuel consumption and black smoke measurement. Superimposed onto the initial results at 0 hour, Figure 2 shows that overall power and torque are not much deteriorated whereas slightly higher diesel fuel consumptions are observed for both engines. However, the significant decrease in black smoke after 300 hours is only shown in engine no. 2 running on biodiesel whereas higher black smoke at high speed in engine no. 1 running on Jatropha blend was from the engine failure by injector and filter clogging. For both engines, black smoke emission results from diesel fuel are not significantly different from the initial condition at 0 hour. Table 2. Properties of palm biodiesel Table 3. Durability test of engine fueled with jatropha oil blend Test no. Duration (hrs) Accumulative duration (hrs) : : :40 4 on-going > :60 (a) Jatropha : Diesel Kubota no. 1 Kubota no. 2 Properties Method Value Methyl Ester Content (%wt.) EN Density (g/cm 3 ) ASTM D Kinematic 40 C (mm 2 /s) ASTM D Flash Point ( C) ASTM D (b) Carbon Residue (%wt) ASTM D Water Content (ppm) ASTM D Oxidation Stability (Hour) EN Acid Value (mg KOH/g) ASTM D ASTM Color ASTM D 1500/ Gross Heat (MJ/kg) ASTM D Cloud Point ( C) ASTM D (c) Pour Point ( C) ASTM D

4 184 BAITIANG, T.et al. Black Smoke % (d) (h) Brake Power Figure 2. (a) Power, (b) torque, (c) fuel consumption and (d) black smoke results for engine no. 1 fueled with 100% jatropha oil; (e)-(h) are for engine no. 2 fueled with 100% biodiesel kw N.m 6 Diesel 0 hour (e) Torque (f) Fuel Consumption Conclusions The engine performance fueled with Jatropha blend and biodiesel is not much different from that with petroleum diesel, with slightly inferior fuel consumption and significantly improved black smoke. The usage of 100% jatropha oil could potentially pose serious problem as the operational time is merely 17 hours while 100% biodiesel posed no harm to the engine up to 500 hours. If neat jatropha oil is to be used with the single-cylinder engine, a blend with 40% diesel is recommended for the normal operation of at least 140 hours. The durability test for 300 hours shows insignificant effect on engine performance (power and torque) but slightly higher diesel fuel consumption. However, significant reduction in black smoke is observed for engine running on biodiesel while slightly higher black smoke at high speed is observed for engine running on Jatropha oil blends. References liter/kw-hr Department of Energy Business Specification of Commercial Fuels quality.html. 2. MTEC Effects of using vegetable oil and biodiesel on low speed and high speed diesel engines. In : Progress report to inhouse project MT-B-49-END I. (g)

5 Effects of Biodiesel and Jatropha oil on Performance, Black Smoke and Durability of Single-Cylinder Diesel Engine Secretariat of the Cabinet Cabinet Resolution, Thailand, Retrieved from 4. US EPA A Comprehensive Analysis of Biodiesel Impacts on Exhaust Emissions. In : Technical report to project EPA420- P