The Comparative Study on Compressed Natural Gas (CNG) and Compressed Biomethane Gas (CBG) Fueled in a Spark Ignition Engine

¹ College of Industrial Technology, King Mongkut’s University of Technology North Bangkok, 1518 Pracharat 1 Road, Wongsawang, Bangsue, Bangkok 10800, Thailand.
² Research Centre for Combustion Technology and Alternative Energy (CTAE), Science and Technology Research Institute, King Mongkut’s University of Technology North Bangkok, Bangkok 10800, Thailand.

^* Corresponding author: kampanart.t@cit.kmutnb.ac.th

Abstract

Compressed biomethane gas (CBG) is an interesting alternative fuel that can be used to solve fossil fuel crisis problems. Nevertheless, it is concerned about engine performance and exhaust gas emission. In additions, CBG can be produced from agricultural harvesting residues and the food industry that is a good opportunity for utilizing biogas as a vehicle fuel. The aims of this research are comparative analysis of the engine performance and exhaust emission on a CBG and compressed natural gas (CNG) fuelled in a spark ignition engine on engine performance and emissions. The engine has been modified to operate with both fuel gases under constant engine load (50% maximum load) and engine speed (1500 - 3500 rpm). The results show that the engine operated with CBG has higher thermal efficiency with lower the nitrogen oxide (NO_x) and hydrocarbon (HC) emissions compared with CNG. Thus, the CBG fuel can be used as an alternative fuel to substitute CNG fuel in the spark ignition engine. In additions, the results give the useful information for developed and optimised the engine operated with compression biogas to impact the higher demand of automotive fuels in the future.