Experimental Investigations and Operating Characterisitics of Diesel Engine using Biodiesel

Transcription

1 Volume 114 No , ISSN: (printed version); ISSN: (on-line version) url: ijpam.eu Experimental Investigations and Operating Characterisitics of Diesel Engine using Biodiesel 1 T.S. Mohanraj, 2 V.S. Barathwaj, 3 M.S. Marshal Andru and 4 S.S. Aravindh Venkatesh 1 School of Mechanical Engineering, SASTRA University. tmraj@mech.sastra.edu 2 School of Mechanical Engineering, SASTRA University. vbarath1996@gmail.com 3 School of Mechanical Engineering, SASTRA University. marshallandrew1996@gmail.com 4 School of Mechanical Engineering, SASTRA University. aravindhvenkatesh4@gmail.com Abstract Biodiesel is a fuel that is made from natural elements such as plants, vegetables, and reusable materials. This type of fuel is better for the atmosphere because, unlike other fuels, it does not give off harmful chemicals which can influence the environment negatively. The popularity of biodiesel is consistently increasing as people search out alternative energy resources. Biodiesel is prepared by the process involving chemical reactions, transesterification and esterification.this involves vegetable or animal fats and oils being reacted with short-chain alcohols typically methanol or ethanol). The alcohols used should be of low molecular weight, ethanol being one of the most used for its low cost. However, greater conversions into biodiesel can be reached using methanol. Although the transesterification reaction can be catalyzed by either acids or bases the most common means of production is base-catalyzed transesterification. This path has lower reaction times and catalyst cost than those posed by acid catalysis. However, alkaline catalysis has the disadvantage of its high sensitivity to both water and free fatty acids present in the oils.the oil content from cottonseed oilis % and it contains long chain fatty acid. Cotton seed oil is rich in palmitic acid (22-26%), oleic acid (15-20%), linoleic acid (49-58%) and 10% mixture of other acid. The FFA present in the raw cotton seed oil is 3.7%. After transesterification, it is reduced to 1.9%. Similarly, the corresponding value of viscosity also is reduced from 34 Cst to 11.1 Cst.With the recent developments in the fuel injection system and more sophisticated components to meet 231

2 emission norms, a good variety of fuels can be successfully used in Compression Ignition (CI) engines.cotton seedoil can be easily blended with diesel in three different blends B10, B20 and B30. Initially the properties of cotton seed oil like calorific value, density, viscosity, %FFA, iodine value, and saponification value were identified and compared with diesel properties. A single cylinder, water cooled, direct injection CI engine at a constant engine speed of 1500 rpm was used for testing at various load conditions. The combustion and emission performance of the engine was obtained and compared with that of diesel. The effect of injection pressure on the engine performance was observed by varying the fuel injection pressure from 195 bar to 215 bar in steps of 5 bar. Since the results are optimum for 205 bar for performance as well as emission characteristics. Key words:cotton seed oil, biodiesel, optimum injection pressure, performance characteristics. 232

3 1. Introduction The rapid depletion of petroleum fuels and their ever increasing costs have led to an intensive search for alternative fuels.the role of the biodiesel industry is not to replace petroleum diesel, but to help create a balanced energy policy with the most benefit to any country. Biodiesel refers to a vegetable oil - or animal fat-based diesel fuel consisting of long-chain alkyl (methyl, ethyl, or propyl) esters. Biodiesel is typically made by chemically reacting lipids(e.g., vegetable oil, soybean oil, [ animal fat (tallow)) with an alcohol producing fatty acid esters. Biodiesel is made through a chemical processcalled transesterification whereby the glycerin is separated from the fat or vegetable oil. The process leaves behind two products -- methyl esters (the chemical name for biodiesel) and glycerin (a valuable byproduct usually sold to be used in soaps and other products).. Diesel fuel can also be replaced by biodiesel made from vegetable oils. The properties of vegetable oils are widely varying due to the physical and chemical changes during handling, stabilization, storage and extraction process [2]. The oxidative reaction during storage necessitates the initial evaluation of the physical and chemical composition of the oil. The oil obtained was treated with stabilizers and stored in leak proof containers. The transesterification procedure required was identified based on the FFA content of the oil [3-5]. Many researchers [6-7] have investigated the use of vegetable oils and highlighted the influence of the following parameters in biodiesel production. The level of free fatty acids, impurities, water content, ash content, acid value, iodine value, saponification value, peroxide value, flash point and kinematic viscosity of the feedstock were determined. [8-10] and the right method of biodiesel production and the kind of pre treatment required were identified. Higher conversion rate was achieved by increasing the temperature and KOH concentration during transesterification and the duration of the process does not have any significant effect [11-13]. The important properties of cotton seed oil obtained were presented in Table 1. Table 1: Properties of cotton seed oil S.no Parameter Diesel Cotton seed oil 1 Density 830 kg/m kg/m 3 2 Kinematic Viscosity 2.54 mm 2 /s 3.95 mm 2 /s 3 Sp. Gravity Calorific value kj/kg kJ/kg 5 Flash point ( o C) Fire point ( o C) Experimental Setup A stationary 4-Stroke, Direct Injection Diesel Engine (Model USHA )was used 233

4 for the experimental work. The performance and emission curves were obtained for different loads and at various injection pressures. The engine specifications were presented in Table 2. Table 2: Engine specifications Engine Single cylinder Diesel Engine Make USHA stationary Diesel Engine Working cycle Four stroke, Diesel Engine Power 3.73 kw Bore x Stroke 100mm x 110mm Cooling system Water cooling Loading setup Brake dynamometer Figure 1: Experimental setup The main performance parameters like BSFC and Brake thermal Efficiency were evaluated. The exhaust gas emissions from the engine were measured by using exhaust gas analyzer. The engine load was varied using mechanical loading (Brake Dynamometer). The brake fuel consumption was measured by using a fuel flow meter. The schematic diagram of experimental setup is shown in Figure Test Procedure The engine performance test was conducted with B10, B20 and B30 blends of cotton seed oil at different load conditions. Similarly the injection pressure are varied at 195 bar, 200 bar, 205 bar, 210 bar and 215 bar and the optimum performance characteristics are obtained at 205 bar only. The tests were conducted at a constant speed of 1500 rpm. The engine was initially allowed to run at no load condition for ten minutes, for each proportion of the blend before 234

5 applying the load. The loads were gradually increased in steps of 25 % upto 100% at constant speed of 1500 rpm. The same procedure was repeated for different Injection pressures for all fuel blends. The exhaust gases are measured by using exhaust gas analyzer from the tail pipe of the engine. The amount of CO, CO 2, HC, O 2, and NOx was measured by an exhaust gas analyzer. 4. Results & Discussions A. Performance Analysis From performance analysis the result obtained, from 195 bar to 215 bar in steps of 5 bar, the optimum performance characterisitcs are obtained at 205 bar. B30 blend has lower SFC value at increased loads at 205 bar whereas B10 and B20 have SFC values greater than B30 blend. The higher injection pressure improves the atomization of biodiesel which leads to better combustion resulting better mixing of fuel with air and decreases the fuel consumption. Figure 2: Variation of 205 bar Figure 3: Variation ofɳ 205 bar 235

6 From the performance curves there is significant increase in the brake thermal efficiency for all blends at 205 bar. Maximum brake thermal efficiency of 29.28% was obtained for maximum load at 205 bar injection pressure with B30 blend. B. Emission Analysis Figure 4: HydroCarbon 205 Bar From emission data, B10 has the lowest hydrocarbon emissions at higher loads at 205 bar whereasb20 and B30 has increased HC concentration particularly at higher loads. This is mainly due to the oxygenated biofuel. Figure 5: Carbon Monoxide 205 Bar The increased volume percentage of cotton seed oil increases the CO % particularly at lower loads. At higher loads the percentage CO formation has lowered significantly for all blends. From the emission curve, B30 blend shows higher CO emissions whereas B10 blend decreases slightly with the corresponding decrease in B20 from 0.19 % to 0.08 %. 236

7 Figure 6: Carbon dioxide 205 bar The percentage carbon dioxide emission was maximum for B20 blend at 205 bar, whereas B10 and B30 blend have carbon dioxide emissions greater than diesel. The variations in CO 2 % with load seem similar for diesel and B 10. Figure 7: NOx 205 bar The NOx formation was high for B20 blend at 205 bar, whereas B10 and diesel has lower NOx formation compared to the other blends for which the NOx formation increases significantly with increased loads. 5. Conclusion The performance and emission characteristics of a direct injection diesel engine fueled with cotton seed oil and its blend have been investigated. The experimental results confirm that the BSTE, SFC and exhaust emissions are 237

8 favour for cotton seed oil blend with increase in injection pressures with most optimum result at 205 bar.the brake specific thermal efficiency of the cotton seed oil was highest for B30 when compared to other blends and it was found to be29.28% at 205 bar injection pressure. This may be due to better combustion, and increase in the energy content of the cotton seed oil. The SFC value is lower for the blend B30 at 205 bar injection pressure with increasing loads when compared to other blends. So we can find that the performance characterisitics of B30 blend is better when compared to other blends and diesel at 205 bar injection pressures. The hydrocarbon emission is lowest for B10 blend operated at maximum load at the given injection pressure. The CO emission of the cotton seed oil is very less for B10 and it is decreased with load at the given injection pressure. The CO 2 emission showsalmost similar trend for all blends and diesel at the given injection pressure.at lower loads, the emission of oxides of nitrogen (NO x ) is almost same for all blends but with increasing loads we find that B20 and B30 is lessat the given injection pressure. The combustion characteristics shows similar trend for all blends with varying injection pressures but the emission characteristics shows significant changes with changes in the blending ratios. Based on the results the performance and emission values are well within the acceptable range for cotton seed oil and it can be used in diesel engine without any major modification in the engine. References [1] Gui M.M., Lee K.T., Bhatia S., Feasibility of Edible vs. Non- Edible oil vs. Waste Edible oil as Biodiesel Feedstock, Energy 32 (2008), [2] Mohanraj T., Murugu Mohan Kumar K., Performance and Emission Characteristics of an Agricultural Diesel Engine using Biodiesel Fuel, International Journal of Engineering 1(4) (2011), [3] Goering C.E., SchwAB A.W., Daugherty M.J., Pryde E.H., Heakin A.J, Fuel Properties of Eleven Vegetable Oils, Transactions of the ASAE 25(6) (1982), [4] Karim G.A., Amoozegar, Determination of Performance of Dual Fuels Engine with Addition of Various Liquid Fuels to the Intake Charge, SAE, (1983). [5] Mohanraj T., Murugu Mohan Kumar K., Operating Characteristics of a Variable Compression Ratio Engine using Esterified Tamanu Oil: International Journal of Green Energy 9(5) (2012), [6] Murugesan A., Umarani C., Chinnusamy T.R., Krishnan M., Subramanian R, Production and Analysis of Bio-Diesel from Non- Edible Oils-A Review, Renewable and Sustainable Energy Reviews 13 (2009),

9 [7] Saravanan S., Nagarajan G., Lakshmi Narayana Rao G., Sampath S., Combustion Characteristics of a Stationary Diesel Engine Fuelled with a Blend of Crude Rice Bran oil Methyl Ester and Diesel, Energy 35 (2010), [8] Szybist J., Song J., Alam M., Boehman A, Biodiesel Combustion, Emissions, and Emission Control, Fuel Processing Technology 88 (2007), [9] SrinivasaRao K., Ramakrishna A., Sundara Siva Rao B.S.K, Experimental Studies on the Characteristics of Diesel Engine with Chicken Fat Methyl Ester, International Journal of Automotive Technology 29(1) (2013), [10] Masjuki H., Abdulmuin M.Z., Sii H.S., Investigation on preheated palm oil methyl esters in the diesel engine, Proceeding Institute of Mechanical Engineering 21 (1996), [11] Onukwuli D.O., Optimization of Biodiesel Production from Refined Cotton Seed oil and its Characterization, Egypt. J. Petrol, (2016). [12] Zheng M., Reader T., Hawley J., Diesel Engine Exhaust Gas Recirculation a Review on Advanced and Novel Concepts, Energy Conservation and Management 45 (2004), [13] Wagner L.E., Clark S.J., Schrock M.D, Effect of Soybean Oil Esters on the Performance-Lubrication Oil and Water of Diesel Engines, Society of Automotive Engineers, (1984). [14] Prem Anand B., Saravanan C.G., Ananda Srinivasan C, Performance and Exhaust Emission of Turpentine Oil Powered Direct Injection Diesel Engine, Renew Energy 35 (2010) [15] Raheman H., Ghadge S.V, Performance of Diesel Engine with Biodiesel at varying Compression Ratio and Ignition Timing, Fuel 87 (2008) [16] Srinivasa Rao P., Gopalakrishnan K.V., Vegeable Oils and Methyl Esters as Fuels for Diesel Engines, Indian Journal of Science and Technology 29 (1991),

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