COMPARATIVE STUDY OF PRODUCER GAS AND LPG BASED POWER PLANT

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1 NSave Nature to Survive 8(1&2): , 2014 COMPARATIVE STUDY OF PRODUCER GAS AND BASED POWER PLANT SAMODINI S. NEVASE 1*, CHITTARANJAN N. GANGDE 1, SANDIP GANGIL 2 AND ANIL KUMAR DUBEY 2 1 Deptartment of Unconventional Energy Sources and Electrical Engg., Panjabrao Deshmukh Krishi Vidyapeeth, Akola , Maharashtra, INDIA 2 Agricultural Energy and Power Division, Central Institute of Agricultural Engineering, Bhopal , Madhya Pradesh, INDIA ABSTRACT INTRODUCTION Bio-energy or biomass power can be obtained by converting the biomass using various technologies viz., combustion, gasification, anaerobic digestion, fermentation etc. Biomass gasification is the process where thermo-chemical conversion of biomass through the process of oxidation and reduction under sub-stoichiometric conditions. The resultant gas known as can be used for fuelling a compression ignition (CI) engine in dual-fuel mode or a spark ignition (SI) engine in gas alone mode. Biomass is the most widely available renewable energy resource. It is carbon dioxide neutral. Estimates have indicated that 15 per cent - 50 per cent of the world s primary energy use could come from biomass by the year Currently, about 11 per cent of the world s primary energy is estimated to be met with biomass (Anonymous, 2010). Harnessing of energy from biomass via gasification route is not only proving to be economical but also environmentally benign. The Ministry of New and Renewable Energy has been promoting multifaceted Biomass Gasifier programmes with a view to utilize locally available surplus biomass resources in rural areas, where biomass such as rice husk, corn cab and stalks, pigeon pea stalks, cotton stalks, small wood chips other agro-residues are available. A programme is being formulated by the Ministry of New and Renewable Energy to set up 200 MW biomass gasifier projects of 2 MW capacities at the tail-end of the grid by The country will be able to convert waste into wealth, If India makes a smooth transition from the present inefficient biomass energy use in traditional sectors to a competitive commercial and efficient biomass energy use. The country s reliance on fossil fuels will be reduced and a sizable amount of funds will be saved by bringing down energy imports and utilizing these resources for further economic development of the country. In principle any IC engine can be converted to run completely or partly on the gas. However in actual practice running the engines uninterrupted and for long periods of time without any problem is difficult to achieve (Kaupp, 1982). Petro-diesel replacements up to per cent have been achieved in the dual fuel mode in compression ignition engine. Because of its poor ignition/delayed ignition characteristics, some minimum amount of petrodiesel is required to start the ignition. When a spark ignition engine is converted to operation on producer gas it is derated to about per cent (Rajvanshi, 1986). Because of very high derating, retrofit applications of existing SI engines for producer-gas operation are less attractive (Banapurmath and Tewari, 2009). Parikh et al. (1989) observed diesel replacement from 68 to 80 per cent at 80 per cent of rated load and maximum power capacity from 3.7 kw to 4 5 kw by changing the volume of the gas cooling-cleaning system. Sridhar et al. (2001) addressed the maximum de-rating of power in gas mode was 16 per cent as compared to the normal diesel mode of operation at comparable compression The current research work was followed to study the performance and the exhaust gas emissions of a 100 percent producer gas power plant and compare those results with system. The Prosopis juliflora was used as biomass fuel for down draft gasifier. Performance evaluation of power plant was carried out by observing the parameters like electrical power output, overall efficiency, exhaust gas temperature, exhaust emission like, CO 2, SO 2 and NOx. Electrical power output, Overall efficiency and Exhaust gas temperature of PG fuelled engine was varied from 04.6 to 12.2 kw, to per cent and 426 to 450ºC respectively and for fuelled engine was varied from 04.9 to 18.0kW, to per cent and 471 to 496ºC respectively as the engine load increased from 5 to 20 kw. Emission of CO 2, SO 2 and NOx from PG fuelled engine was varied from 10.1 to 12.0 per cent, 1.1 to 1.9 per cent, and 31 to 105 ppm respectively and from fuelled engine was varied from 3.9 to 07.5 per cent, 0.9 to 1.2 per cent and 78 to 170 ppm respectively as the engine load increased from 5 to 20 kw. KEY WORDS Power plant Received : Revised : Accepted : *Corresponding author 115

2 SAMODINI S. NEVASE et al., ratio, whereas, the overall efficiency declined by 32.5 per cent. Aung (2008) described that after converting the 26.5kW diesel engine to producer gas engine the power output of producer gas engine was 40 per cent less than that of original diesel engine. Shah et al. (2010) presented that for syngas operation, the overall efficiency was the least at maximum electrical power output despite feeding the highest flow rate of syngas to the generator. In view of above presentation the current research work was followed with major objective to study the performance and the exhaust gas emissions of a 100 percent producer gas power plant and compare those results with system. MATERIALS AND METHODS Biomass gasifier The gasifier was Ankur Scientific, Vododara, Gujarat make downdraft type with rotating grate. The fuel storage capacity of gasifier is 200 kg. The current research work was followed by Prosopis juliflora which was procured, from local market of Bhopal (M.P.). Size of wood pieces maintained not more than 30 mm X 50 mm and the moisture content of wood maintained less than 15per cent. Experimental setup Biomass based 20 kw power plant consists of down draft gasifier having rotating grate, venturi scrubber, three filters (one coarse and two fine) connected in series, one security filter and gas engine generating set (Prakash Make, Sr. No , Spark Ignition (SI), twin cylinder, water cooled, Governor linked control butterfly, running on 100 per cent producer gas, Speed 1500 rpm). Engine was loaded with a resistive loading device consist of each 500 W bulb in 45 numbers. A control panel fitted with MCB was also integrated to ON or OFF the bulb loading device. flow rate was measured online by orifice meter connected between safety filter and genset. Also, air flow rate was measured online by orifice meter connected separately in the air-box. PA-2400 flue gas analyzer was used for measurement of exhaust gas emission. Power measurement was done by CW240 Power 1. Storage tank, 2. Multifunctional valve, 3. Gas solenoid valve, 4. Copper tube, 5. Veporizer, 6. gas outlet, 7. Water pipe, 8. gas inlet, 9. inlet, 10. Air inlet, 11. Switch Figure 1: gas kit assembled with genset meter manufactured by Yokogawa Meters and Instrument Corporation, India. For operation, the system was provided with gas kit (Fig. 1) also the flow rate was recorded by Thermal anemometer 642. System process description The biomass is fed through the feed door and is stored in the hopper. Limited and controlled amount of air for partial combustion enters through air nozzles. The throat (or hearth) ensures relatively clean and good quality gas production. The reactor holds charcoal for reduction of partial combustion products while allowing ash to drop off in the ash pond. The gas passes through the annulus area of reactor from the upper portion of the perforated sheet. The gas outlet is connected with the various downstream systems viz. venturi scrubber, drain box, coarse filter, flare with valve, engine gas control valve, fine filters, safety filter and engine shut-off valve. Gas produced in the gasifier scrubbed and cooled in venturi scrubber with recirculating cooling water in cooling pond with help of AC scrubber pump. Gas is separated from water in drain box and introduced in coarse filter, fine filters and safety filters. Cool, clean gas and air is then sucked into the engine through a mixer butterfly consisting of piping and valves arrangement. The gasifier is started with battery (12 V), which initially provides auxiliaries power to AC scrubber pump, to start the gasifier system. A battery-operated electric starts the engine; the producer gas then starts the engine on gas mode. Load variation was done from 25 per cent (5 kw), 50 per cent (10 kw), 75 per cent (15 kw) to 100 per cent (20 kw). Performance evaluation of power plant was carried out by observing the parameters like electrical power output, overall efficiency, exhaust gas temperature, exhaust emission like, CO 2, SO 2 and NOx. RESULTS AND DISCUSSION Electrical power output Effect of fuel on electrical power output at different load variations is graphically presented in Fig. 2. Result shows that increase in engine load result increase in electrical power output. Fully loaded engine established significantly highest electrical power output than rest of the engine load. fuelled engine observed significantly highest electrical power output than producer gas. This was mainly attributed by low calorific value of producer gas, low engine rpm and variation in producer gas composition according to combustion in reactor. Aung (2008) observed 40 per cent power loss for producer gas fuelled engine. Shah et al. (2010) reported for power rating 4, although syngas flow rate was the highest, the generator s electrical power output was not the highest. Overall efficiency Overall efficiency is calculated for producer gas and based engine system and graphically presented in Fig. 3. It was observed that as the engine load increased the overall efficiency increased significantly for fueled engine. For producer gas, the overall efficiency increased significantly up to 15kW but lowered at 20 kw. This may be due to lower calorific value of producer gas than. Also for producer 116

3 PRODUCER GAS AND BASED POWER PLANT gas operation the overall efficiency was lower for 20 kw power despite feeding highest flow rate of producer gas to the generator. This could be attributed to the inability of the generator to utilize all the producer gas fed to it. Shah et al. (2010) found increased overall efficiency with increased brake power for 100 per cent syngas based engine operation. Yusuf et al. (2011) found increased engine efficiency with increased load for based engine operation. Exhaust gas temperature Effect of fuel on exhaust gas temperature at different load variations is graphically presented in Fig. 4. Exhaust gas temperature reflects directly the combustion temperature and influences the emission characteristics. fuelled engine reported significantly lowest exhaust gas temperature than the. Because of inability of engine to utilize the producer gas the incomplete combustion takes place and ultimately exhaust gas temperature decreased. Increased engine load resulted increased exhaust gas temperature. This was mainly attributed by increased combustion temperature as the load increased. Unloaded engine established significantly lowest exhaust gas temperature. Goto et al. (2000) shown the increased exhaust gas temperature of fuelled engine with increased load percentage. Yusuf et al. (2011) shown that the exhaust gas temperature of fuelled engine Electrical power output (kvv) PG were higher. Carbon dioxide emission Effect of fuel on carbon dioxide emission at different load variations is graphically presented in Fig. 5. fuelled engine reported significantly lowest emission of carbon dioxide than and other fuel blend. Increased engine load result increased emission of carbon dioxide. CO 2 emission was significantly higher in producer gas than and blends, this was might be because of higher carbon content in producer gas flow. Uma et al. (2004) found increased CO 2 with engine load when operated with diesel and producer gas in dual fuel mode. Singh et al. (2007) reported increased CO 2 with engine load when operated with diesel and producer gas in dual fuel mode. Shah et al. (2010) observed increased CO 2 concentration 33 to 167 per cent for syngas operation compared to the gasoline operation. Hassan et al. (2011) observed increased trend in CO 2 with increased engine load producer gas dual fuel engine. Yusuf et al. (2011) reveled that concentration of CO 2 becomes higher when load is increased for fuelled engine compared to gasoline. Sulphur dioxide emission Effect of fuel on sulphur dioxide at different load variations is graphically presented in Fig. 6. Emission of SO 2 increased with 20 Overall efficiency (%) PG Figure 2: Effect of engine load on electrical power output Figure 3: Effect of engine load on overall efficiency Exhaust gas temperature ( C) Carbon dioxide (%) Figure 4: Effect of engine load on Exhaust gas temperature 2 Figure 5: Effect of engine load on emission of carbon dioxide. 117

4 SAMODINI S. NEVASE et al., Sulphur dioxide (ppm) Nitrogen oxide (ppm) Figure 6: Effect of engine load on emission of sulphur dioxide significantly increased with engine load increased from 0 to 20 kw. The significantly highest emission of SO 2 was observed at producer gas rather than might be due to presence of sulphur in Prosopis juliflora. Uma et al. (2004) observed found increased SO 2 with engine load but increased when operated in dual fuel mode compared to diesel mode. Nitrogen oxide emission Effect of fuel on Nitrogen oxide emission at different load variations is graphically presented in Fig. 7. fuelled engine established significantly lowest emission of NOx than. Also, increased in engine load resulted significantly increase in emission of NOx. Unloaded engine established significantly lowest emission of NOx than other engine load. This shows the dependence of NOx formation on the temperature generated within engine cylinder as it was expected that the temperature will be higher during higher electrical power output. The NOx emission at producer gas was lowered might be because of lower heating value of producer gas resulting lesser reaction between nitrogen and oxygen. Goto et al. (2000) observed increased NOx emission with engine load when operated on. Uma et al. (2004) shown increased NOx emission at all engine load condition when operated in duel fuel mode with producer gas and diesel. Lekpradit et al. (2008) reported increased NOx emission at all engine load condition when operated in duel fuel mode with producer gas and diesel. Shah et al. (2010) found increased NOx emission with increased engine load when operated on 100 per cent producer gas. Hassan et al. (2011) found increased NOx emission with increased engine load when operated on producer gas and diesel in dual fuel mode. Yusuf et al. (2011) reported increased NOx emission with engine load when operated on. CONCLUSIONS Electrical power output of PG, and fuelled engine was varied from 04.6 to 12.2, and 04.9 to 18.0kW respectively as the engine load increased from 5 to 20 kw. Overall efficiency of PG, and fuelled engine was varied from to 09.48, and to per cent respectively as the engine load increased from 5 to 20 kw. Exhaust gas temperature of PG 0 Figure 7: Effect of engine load on emission of nitrogen oxide. and fuelled engine was varied from 426 to 450 and 471 to 496 o C respectively as the engine load increased from 5 to 20 kw. Emission of Carbon dioxide from PG and fuelled engine was varied from 10.1 to 12.0, and 3.9 to 07.5 per cent respectively as the engine load increased from 5 to 20 kw. Emission of sulphur dioxide from PG, and fuelled engine was varied from 1.1 to 1.9, and 0.9 to 1.2 per cent respectively as the engine load increased from 5 to 20 kw. Emission of nitrogen oxide from PG and fuelled engine was varied from 31 to 105 and 78 to 170 ppm respectively as the engine load increased from 5 to 20 kw. REFERENCES Anonymous Biomass. New Delhi, Ministry of New and Renewable Energy. p. 7. Aung, N. Z Modification of diesel engine to producer gas engine. J. Ilm. Tek. Energi. 1(6): Banapurmath, N. R. and Tewari, P. G Comparative performance studies of a 4-stroke CI engine operated on dual fuel mode with producer gas and Honge oil and its methyl ester (HOME) with and without carburetor. Renewable Energy. 34(4): Goto, S., Lee, D., Harayama, N., Honjo, F., Ueno, H., Honma, H., Wakao, Y. and Mori, M Development of SI and CI Engines for Heavy Duty Vehicles. Seoul 2000 FISITA World Automotive Congress June 12-15, 2000, Seoul, Korea. F2000A171. Hassan, S., Zainal, Z. A. and Miskam, M. A Effects of advanced injection timing on performance and emission of a supercharged dual-fuel diesel engine fueled by producer gas from downdraft gasifier. J. Scientific and Industrial Research. 70: Kaupp, A Myths and facts about gas producer engine systems. Paper presented at first International Producer Gas Conference, Colombo, Shri Lanka. pp Lekpradit, T., Tongorn, S., Nipattummakul, N. and Kerdsuwan, S Study on Advanced Injection Timing on a Dual-Fuel Diesel Engine with Producer Gas from a Down-Draft Gasifier for Power Generation. J. Metals, Materials and Minerals. 18(2): Parikh, P.P., Bhave, A. G. Kapse, D. V. and Shashikantha Study of thermal and emission performance of small gasifier-dualfuel engine systems. Biomass. 19(1-2): Rajvanshi, A. K Alternative Energy in Agriculture. Vol. II, Ed. D. Yogi Goswami, CRC Press. pp Shah, A., Srinivasan, R., Filip, S. D. and Columbus, E. P

5 PRODUCER GAS AND BASED POWER PLANT Performance and emissions of a spark-ignited engine driven generator on biomass based syngas. Bioresource Technology. 101(12): Singh, R. N. Singh, S. P. and Pathak, B. S Performance of CI engine with progressive replacement of blended plant oil by producer gas. J Agricultural Engineering. 44(2): Sridhar, G., Paul, P. J. and Mukunda, H. S Biomass derived producer gas as a reciprocating engine fuel-an experimental analysis. Biomass and Bioenergy. 21(1): Uma, R., Kandpal, T. C. and Kishore, V. V. N Emission characteristics of an electricity generation system in diesel alone and dual fuel modes. Biomass and Bioenergy. 27(2): Yusuf, T., Saleh, K. H. and Said, M. A Engine performance and emission analysis of -SI engine with the aid of artificial neural network. Proceedings of the Institution of Mechanical Engineers, Part A: J. Power and Energy. 119

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