CONTROL OF POLLUTANTS WITH CATALYTIC CONVERTER AND COPPER COATED CYLINDER HEAD IN METHANOL- GASOLINE BLEND OPERATED TWO STROKE SI ENGINE

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1 International Journal of Mechanical Engineering and Technology (IJMET) Volume 6, Issue 6, June 2015, pp , Article ID: IJMET_06_06_013 Available online at Journal Impact Factor (2015): (Calculated by GISI) ISSN Print: and ISSN Online: IAEME Publication CONTROL OF POLLUTANTS WITH CATALYTIC CONVERTER AND COPPER COATED CYLINDER HEAD IN METHANOL- GASOLINE BLEND OPERATED TWO STROKE SI ENGINE Dr. K. Kishor Assistant Professor, Mechanical Engineering Department, CBIT, Hyderabad, India ABSTRACT Experiments were conducted to evaluate and control the exhaust emissions from two stroke single cylinder, spark ignition (SI) engine, with alcohol blended gasoline (80% gasoline, 20% methanol, by volume) having copper coated engine [C, copper-(thickness, 300 μ) coated on inner surface of the cylinder head] provided with catalytic converter with sponge iron and manganese as as catalysts and compared with conventional SI engine () with pure gasoline operation. The exhaust emissions of Carbon Monoxide (CO) and Unburnt Hydrocarbons (UBHC) were determined at different values of Brake Mean Effective Pressure (BMEP) with Netel Chromatograph CO/UBHC analyzer. Aldehyde levels were determined by Dinitrophenyl Hydrazine (DNPH) method. Copper coated combustion chamber with alcohol blended gasoline with catalytic converter using sponge iron catalyst with air injection significantly reduced the pollutants in comparison with with pure gasoline operation. Key words: Aldehydes, CO, DNPH, Exhaust emissions, UBHC Cite this Article: Dr. K. Kishor. Control of Pollutants with Catalytic Converter and Copper Coated Cylinder Head In Methanol- Gasoline Blend Operated Two Stroke Si Engine, International Journal of Mechanical Engineering and Technology, 6(6), 2015, pp INTRODUCTION The paper is divided into i) Introduction, ii) Materials and methods, iii) Results and discussion, iv) Conclusions, research findings, future scope of work followed by references

2 Control of Pollutants with Catalytic Converter and Copper Coated Cylinder Head In Methanol- Gasoline Blend Operated Two Stroke Si Engine Alcohols are the promising substitutes for the base fuel (gasoline) being used in SI engines, as their properties are compatible to those of gasoline fuels. The use of alcohol in small quantities poses no problem in SI engines. Performance of the engine can also be improved with the change of fuel composition with alcohol-gasoline blends in SI engines. Out of the two alcohols available (methyl alcohol and ethyl alcohol), methyl alcohol is preferred to ethyl alcohol, as it is not harmful. Methyl alcohol has got properties compatible to those of gasoline and its octane rating is m than 100. Also, methyl alcohol can be manufactured even from the municipal solid wastes. When SI engines are run with alcohols, the major emissions are CO and UBHC, besides aldehydes. As the exhaust emissions of CO (%), UBHC (ppm) and aldehydes (% concentration) cause harmful health hazards on human beings and on environment, necessary steps are to be taken in the form of changing the fuel composition or engine design modification or both, to decrease them. Coupling catalytic converter to the engine is a simple technique to decrease the exhaust emissions from the engine. Catalytic converters are to be provided with suitable and cheap catalysts like sponge iron and manganese, to reduce the exhaust emissions. Murali Krishna et al. [1] conducted experiments for controlling the pollutants from an engine [2]. The engine parameters have substantial effects in reducing the emissions. Injection of heated air in to the catalytic converter has drastically reduced the emissions. Methyl alcohol blend in catalytically activated engine decreased the pollutants in comparison with the base engine. In this work, experiments were conducted on a single cylinder, air-cooled, Bajaj make, two-stroke SI engine, with a brake power of 2.2 kw at a rated speed of 3000 rpm with a compression ratio of 7.5:1 with base fuel (gasoline) and methyl alcohol blend (gasoline-80%, methanol- 20% by volume), for various configurations of the engine such as base engine () and catalytically activated engine (C, inner surface of the cylinder head being coated with copper) and being provided with catalytic converter along with air injection employing sponge iron ()/manganese () catalyst and the experimental results were compared with the base engine. Exhaust emissions of CO, UBHC aldehydes (formaldehydes and acetaldehydes) were controlled by catalytic converter with sponge iron as catalyst. 2. MATERIALS AND METHODS This section deals with fabrication of copper coated engine (C, inner surface of the cylinder head being coated with copper), description of experimental set up employing catalytic converter using sponge iron/manganese catalysts. In the copper coated engine, by flame spraying technique, a high thermal conductive catalytic material like copper was coated on the inner surface of cylinder head. A bond coating of nickel-cobalt-chromium was sprayed for a thickness of 100µ. On this coating, an alloy of copper (89.5%), aluminium (9.5%) and iron (1%) was coated for 300µ thickness, with a METCO flame spray gun. Dhandapani et al. [3, 4] conducted experiments on copper coated SI engine with gasoline as fuel and life test was carried out for 50 hours. During these 50 hours, wear and tear was not reported from the engine editor@iaeme.com

3 Dr. K. Kishor Plate-1 shows the photographic view of copper coated cylinder head. Plate 1 Photographic view of copper coated cylinder head Figure 1 shows the schematic diagram of the experimental set up that was employed to analyze the exhaust emissions from the engine. 1. Engine, 2. Electrical swinging field dynamometer, 3. Loading arrangement, 4. Fuel tank, 5. Torque indicator/controller sensor, 6. Fuel rate indicator sensor, 7. Hot wire gas flow indicator, 8. Multi- channel temperature indicator, 9. Speed indicator, 10. Air flow indicator, 11. Exhaust gas temperature indicator, 12. Mains ON 13. Engine ON/OFF switch, 14. Mains OFF, 15. Motor/Generator option switch, 16. Heater controller, 17. Speed indicator, 18. Directional valve, 19. Air compressor, 20. Rotometer, 21. Heater, 22. Air chamber, 23. Catalytic chamber, 24. CO/HC analyzer, 25. Filter, 26. Round bottom flasks containing DNPH solution Figure 1 Schematic diagram of the experimental set up An air-cooled single-cylinder 2.2 kw BP two-stroke SI engine with a rated speed of 3000 rpm was provided with an electrical swinging field dynamometer for the measurement of brake power (BP). CO and UBHC emissions in engine exhaust were measured with Netel Chromatograph analyzer. Aldehyde emissions (formaldehydes and acetaldehydes) are measured with wet chemical (DNPH) method [5]. A catalytic converter [6] (Figure.2) is fitted to exhaust pipe of engine [7]. Provision is also made to inject a definite quantity of air into catalytic converter. Air quantity drawn from compressor and injected into converter is kept constant so that backpressure does not increase. Aluminium was coated at the inner surface of catalytic converter for a thickness of 500 microns and was superior to existing one in order to reduce the editor@iaeme.com

4 Control of Pollutants with Catalytic Converter and Copper Coated Cylinder Head In Methanol- Gasoline Blend Operated Two Stroke Si Engine pollutants effectively. The catalytic converter was tested with a number of catalysts and out of which Sponge Iron and Manganese were proved to be effective in reducing the pollutants. Hence they were selected as catalysts and the performance of one catalyst was compared with the performance of other catalyst. Note: All dimensions are in mm Air chamber, 2. Inlet for air chamber from engine, 3. Inlet for air chamber from compressor, 4. Outlet for air chamber, 5. Catalytic chamber, 6. Outer cylinder, 7. Intermediate-cylinder, 8. Inner-cylinder, 9. Inner sheet, 10. Intermediate sheet, 11. Outer sheet, 12. Outlet for exhaust gases, 13. Provision to deposit the catalyst, and, 14. Insulation. Figure 2 Details of Catalytic converter 3. RESULTS AND DISCUSSION This section deals with i). Variation of CO emissions with BMEP, ii) variation of UBHC emissions with BMEP, and iii) data of Aldehyde emissions (Formaldehydes and Acetaldehydes) Exhaust Emissions Provision of catalytic converter and different operating conditions of catalytic converter are, Set-A: Without catalytic converter and without air injection; Set-B: With catalytic converter and without air injection; and Set-C: With catalytic converter and with air injection. The data of CO emissions {magnitude and the % deviation over the base condition (base engine-base fuel-set-a catalyst)} from the base engine and catalytic coated engine (copper coated cylinder head) using experimental fuels under various sets of catalytic converter with (Sponge Iron) / (Manganese) catalyst was presented in the TABLE editor@iaeme.com

5 Dr. K. Kishor TABLE 1 Data of CO emissions (%) at full load operation and the % deviation over base condition operation Engine version Base engine Catalytic coated engine Fuel used Base fuel Methyl alcohol blend Base fuel Methyl alcohol blend Set-A Set-B Set-C Catalyst Conditions Magnitude % deviation % % -18.1% -18.1% -49.1% % Magnitude % deviation -40% -20% % % -50.9% -34.5% -69.5% % Magnitude % deviation -60% -40% % % -67.2% -50.9% -79.6% % Table-1 indicated that, C was m effective in reducing the pollutants in comparison with the base engine with both catalysts, as good combustion is achieved due to turbulence with copper coating. Air injection further reduced the pollutants due to oxidation reactions in both the engine versions. catalyst was found to be m effective in reducing the CO emissions in comparison with for both engine versions using experimental fuels. Methyl alcohol blend in C reduced the CO emissions with the use of sponge iron catalyst and that with air injection in to the catalytic converter, CO emissions were decreased further. The data of UBHC emissions {magnitude and the % deviation over the base condition (base engine-base fuel-set-a catalyst)} from the base engine and catalytic coated engine (copper coated cylinder head) using experimental fuels under various sets of catalytic converter with (Sponge Iron) / (Manganese) catalyst was presented in the TABLE.2. TABLE 2 Data of UBHC emissions (PPM) at full load operation and the % deviation over Engine version Base engine Catalytic coated engine Fuel used Base fuel Methanol blend Base fuel Methanol blend Catalyst Conditions Set-A Set-B Set-C Magnitude % deviation % % -18.4% -18.4% -43.4% -43.4% Magnitude % deviation -40% -20% -57.3% -43.1% -51% -34.7% - 66% - 54% Magnitude % deviation -60% -40% % % -67.3% -51% -77.3% -66 % It was seen in the TABLE.2 that, UBHC emissions followed the similar trends that were observed with CO emissions. However, UBHC emissions depends on quenching area (accumulation of fuel in crevices), while CO emissions depend on editor@iaeme.com

6 Control of Pollutants with Catalytic Converter and Copper Coated Cylinder Head In Methanol- Gasoline Blend Operated Two Stroke Si Engine incomplete combustion. There may be quantitative difference between these two, but qualitatively their behavior is the same. Methyl alcohol blend reduced the UBHC emissions with the use of sponge iron catalyst and that with air injection in to the catalytic converter, UBHC emissions were decreased further. TABLE.3 shows the data of Formaldehyde and Acetaldehyde emissions. TABLE 3 Data of aldehyde emissions (% concentration) at full load and the % deviation over Aldehyde emissions Cataly st Test fuel Base fuel Methyl alcohol blend Engine Condition C % variation of C over C % variation of C over Formaldehyde emissions Acetaldehyde emissions Sponge iron Sponge iron Set-A % % Set-B % % Set-C % % Set-A % % Set-B % % Set-C % % Set-A % % Set-B % % Set-C % % Set-A % % Set-B % % Set-C % % From the TABLE.3 it was observed that, with the provision of catalytic converter coupled with injection of air, both the aldehyde emissions were decreased. C decreased both aldehyde emissions in comparison with the base engine using the experimental fuels. This was due to improved combustion so that there was no formation of incomplete combustion products. Sponge iron catalyst effectively reduced both the aldehyde emissions over for both engine configurations using experimental fuels. Hence C with Sponge iron catalyst along with air injection in to catalytic converter was m suitable in reducing both the aldehyde 4. CONCLUSIONS 1. Catalytic coated engine with methyl alcohol blend and sponge iron catalyst decreased the CO emissions and UBHC emissions by 69.5% and 66% respectively without air injection, while the emissions were decreased by 79.6% and 77.3% respectively with air injection in comparison with the base engine. 2. With methyl alcohol blend and manganese catalyst, catalytic coated engine decreased the CO emissions and UBHC emissions by 59.3% and 54% respectively without air injection, while they were decreased by 69.4% and 66% respectively with air injection, in comparison with the base engine operation. 3. Formaldehyde emissions and acetaldehyde emissions, from the base engine and catalytic coated engine using both experimental fuels, were decreased with injection of air in to catalytic converter. 4. Sponge iron catalyst was m effective in reducing exhaust emissions in comparison with manganese for both configurations of the engine using experimental fuels editor@iaeme.com

7 Dr. K. Kishor 4.1. Research findings and future scope of work The control of exhaust emissions with copper coating on the inner surface of cylinder head with catalytic converter employing catalysts was systematically investigated. Copper coating can also be done on the top surface of piston crown in addition to the inner surface of cylinder head to decrease the pollutants further. ACKNOWLEDGEMENTS Authors thank authorities of Chaitanya Bharathi Institute of Technology, Hyderabad for facilities provided. Financial assistance from Andhra Pradesh Council of Science and Technology (APCOST), Hyderabad, is greatly acknowledged. Authors sincerely thank authorities of M/S Sai Surface Coating (P) Limited, Patancheru, Hyderabad, for extending the cooperation in coating the components of the SI engine. REFERENS [1] M.V.S. Murali Krishna, and K. Kishor, Control of pollutants from copper coated spark ignition engine with methanol blended gasoline, Indian Journal of Environmental Protection, 25 (8), 2005, [2] M.V.S. Murali Krishna, and K. Kishor, Investigations on catalytic coated spark ignition engine with methanol blended gasoline with catalytic converter, Indian Journal (CSIR) of Scientific and Industrial Research, 67, 2008, ,. [3] S. Dhandapani, Thetical and experimental investigation of catalytically activated lean burn combustion, doctoral diss., Indian Institute of Technology, Madras, [4] N. Nedunchezhian, and S. Dhandapani, Experimental investigation of cyclic variation of combustion parameters in a catalytically activated two-stroke SI engine combustion chamber, Engg Today, ISSN: , 2, 2000, [5] Inove To Kuta, Oishi Kiyohiko, and Tanaka To Shiaki, Determination of aldehydes in the automobile exhaust by HPLC, Toyota Automobile Company, Technical Improvement Division, Toyota, Japan, 21(4), 1980, [6] M.V.S. Murali Krishna, K. Kishor, and Ch. V. Ramana Reddy, Control of carbon monoxide emission in spark ignition engine with methanol blended gasoline and sponge iron catalyst, Ecology, Environment &Conservation. 13(4), 2008, [7] K. D. Sapate and A. N. Tikekar. Comparative Study of Two Stroke Spark Ignition Carburettor Mode with Direct Injection Mode Engine, International Journal of Mechanical Engineering and Technology, 4(5), 2013, pp [8] M.V.S. Murali Krishna, K. Kishor, P.V.K. Murthy, A.V.S.S.K.S. Gupta, and S. Narasimha Kumar, Comparative studies on performance evaluation of four stroke copper coated spark ignition engine with catalytic converter with alcohols, International Journal of Advances in Engineering Research, ISSN: , 2(6), 2011, [9] Ch. Indira Priyadarsini, M.V.S. Murali Krishna and P. Ushasri, Studies on Control of Aldehydes From Four Stroke Copper Coated Spark Ignition Engine with Methanol Blended Gasoline with Improved Design of Catalytic Converter, International Journal of Mechanical Engineering and Technology, 5(4), 2015, pp editor@iaeme.com