Energy consumption and emissions of diesel-CNG dual fuel engine at high load operation

Global warming and energy sustainability issues are among the major world concern. Malaysian National Green Technology Policy 2009 and Thailand Power Development Plan 2015-2036 (PDP 2015) were launched to enhance the green and sustainable energy usage. Meanwhile in the transportation sector, National Automotive Policy (NAP) has been implemented and revised to enhance the usage of the green energy, in order to achieve a low carbon emission and energy efficient vehicle. Researchers keep striving to find alternative solutions to power vehicles by cleaner energy efficiently. Compressed Natural Gas (CNG) has lower carbon emission and higher energy density compared to common petroleum fuel. It provides an opportunity to power the vehicle cleanly. Thus, it has been used as an alternative for fueling gasoline engine. However, CNG fuel is difficult to be applied on diesel engine. Unlike gasoline engine, diesel engine does not have spark plug and its fuel is combusted through compression in cylinder. Since CNG has high octane number, it is difficult to self-ignite in diesel engine. Therefore, Diesel-CNG Dual Fuel (DDF) system is applied. The system use CNG as part fuel and certain amount of diesel pilot fuel is injected into the cylinder to ignite the combustion. DDF engine may potentially reduce Carbon Dioxide (CO2) emission. However, high fuel consumption and Nitrogen Oxide (NOX) emission have been observed at high load engine operation due to improper fuel ratio. In this study, four ratios of DDF were tested and compared with 100% diesel: 90D10G, 80D20G, 70D30G, 60D40G. It was found that each of the fuel ratio behaved differently in terms of brake specific energy consumption (BSEC) and exhaust emissions

Energy consumption and emissions of diesel-CNG dual fuel engine at high load operation

Global warming and energy sustainability issues are among the major world concern. Malaysian National Green Technology Policy 2009 and Thailand Power Development Plan 2015-2036 (PDP 2015) were launched to enhance the green and sustainable energy usage. Meanwhile in the transportation sector, National Automotive Policy (NAP) has been implemented and revised to enhance the usage of the green energy, in order to achieve a low carbon emission and energy efficient vehicle. Researchers keep striving to find alternative solutions to power vehicles by cleaner energy efficiently. Compressed Natural Gas (CNG) has lower carbon emission and higher energy density compared to common petroleum fuel. It provides an opportunity to power the vehicle cleanly. Thus, it has been used as an alternative for fueling gasoline engine. However, CNG fuel is difficult to be applied on diesel engine. Unlike gasoline engine, diesel engine does not have spark plug and its fuel is combusted through compression in cylinder. Since CNG has high octane number, it is difficult to self-ignite in diesel engine. Therefore, Diesel-CNG Dual Fuel (DDF) system is applied. The system use CNG as part fuel and certain amount of diesel pilot fuel is injected into the cylinder to ignite the combustion. DDF engine may potentially reduce Carbon Dioxide (CO2) emission. However, high fuel consumption and Nitrogen Oxide (NOX) emission have been observed at high load engine operation due to improper fuel ratio. In this study, four ratios of DDF were tested and compared with 100% diesel: 90D10G, 80D20G, 70D30G, 60D40G. It was found that each of the fuel ratio behaved differently in terms of brake specific energy consumption (BSEC) and exhaust emissions

Design and test of a continuous reactor for palm oil transesterification

The continuous reactor for transesterification of refined palm oil with methanol was designed and tested. The reaction condition was focused at ambient pressure, temperature of 60ºC, molar ratio of alcohol to oil of 6:1, and NaOH of 1.0 %wt of oil. The designed reactor was in a form of a 6-stage mechanically stirred tank. Rushton turbines, with 4 standard baffles, and plates with a small opening were installed inside. The reactor has a simple form which could be conveniently constructed and operated. The reactor could produce methyl esters (ME) with purities ranging from 97.5-99.2 %wt within residence times of 6-12 minutes in which its production performance was equivalent to a plug flow reactor and the power consumption of a stirrer in the range of 0.2-0.6 kW/m3 was required. The reaction modeling based on a homogeneous concentration field with reaction kinetics could accurately predict the produced purities of ME. The production yields by weight of final product and of ME to the fed oil were 94.7 and 92.3%, respectively. The developed continuous reactor has good potential for producing ME to be used as biodiesel

Design and test of a continuous reactor for palm oil transesterification

The continuous reactor for transesterification of refined palm oil with methanol was designed and tested. The reaction condition was focused at ambient pressure, temperature of 60ºC, molar ratio of alcohol to oil of 6:1, and NaOH of 1.0 %wt of oil. The designed reactor was in a form of a 6-stage mechanically stirred tank. Rushton turbines, with 4 standard baffles, and plates with a small opening were installed inside. The reactor has a simple form which could be conveniently constructed and operated. The reactor could produce methyl esters (ME) with purities ranging from 97.5-99.2 %wt within residence times of 6-12 minutes in which its production performance was equivalent to a plug flow reactor and the power consumption of a stirrer in the range of 0.2-0.6 kW/m 3 was required. The reaction modeling based on a homogeneous concentration field with reaction kinetics could accurately predict the produced purities of ME. The production yields by weight of final product and of ME to the fed oil were 94.7 and 92.3%, respectively. The developed continuous reactor has good potential for producing ME to be used as biodiesel