Use of Methane-Free Synthesis Gases as Fuel in an Spark Ignition Combustion Engine

The presented article deals with the use of methane-free synthesis gases in a spark-ignition internal combustion engine. The authors analyse the influence of seven synthesis gases on integral as well as internal parameters of the engine and make comparisons with operation on methane. The main combustible components of the synthesis gas are hydrogen and carbon monoxide and the remainder are inert gases (nitrogen and carbon dioxide). At the operating speed of the combustion engine of 1500 rpm, at which the cogeneration unit operates, in comparison with methane a decrease in power parameters was recorded in the range from 19 to 35%. The increase in the hourly fuel consumption was 6 to 8 times higher. Depending on the gas composition, the optimum start of ignition angle at full load ranged from 17 to 26 °CA BTDC. In terms of analysis of internal parameters, the cyclic variability of the pressure in the engine cylinder, which characterizes the stability of its operation, was in synthesis gases operation mostly at a lower level (from 3.6% to 6.9%) than in methane operation (6.8%). Due to the presence of hydrogen, the main combustion time interval of all synthesis gases has been shorter compared to methane. The presented results serve to better understand the setting of the waste gasification process so that the highest possible energy and economic recovery in the cogeneration unit is obtained.