Fumigation of Producer Gas in a Diesel Genset: Performance and Emission Characteristics

Gasification is a thermo-chemical process, which convert solid biomass into combustible gas called producer gas. In this study a combustion of producer gas was combined with the diesel fuel to determine its engine performance and the emission produced. The study focused on the maximum diesel fuel replacement rate applied in an induced-draft based gasification set - up. This paper investigate the effect of a producer gas flow rate on the engine performance by using the force-draft based gasifier. A mixture of Jatropha seed and Jatropha press-cake in 1:1 ratio (volumetric basis) was used as the feedstock for the throat less downdraft gasifier. The gaseous product was used in a 2.5 kWe (Kilowatts electrical) diesel generator set to partially replace the diesel fuel. Two producer gas flow rates were chosen in studying the engine performance and emission characteristics: 10 kg/h and 20 kg/h. The engine load was varied from 0.5 kWe to 2.0 kWe in 500 We increment. The result showed that the diesel fuel replacement was maximized at 1 kWe. Diesel fuel replacement rate is higher at the higher fuel gas flow rate. The maximum diesel fuel saving was 70% when 20 kg/h gas is introduced, and the engine was operated at 1.0 kWe load or 40% at full load. The specific diesel fuel consumption was found to be lower at dual fuel mode as compared with single diesel mode in over the entire load range. CO and CO₂ emission increased with the increase in gas flow rate for all loads.