Waste Biomass Gasification Characteristics in a Fixed Bed Gasifier

The gasification processes to convert low grade solid fuels into valuable fuels have been used in various applications, but the biomass gasification has only been used in small scale processes because the quantity of biomass supply generally is unstable. However the biomass gasification processes is widely developed due to the highly price of oil and the concern of climate change. Using results from the basic data and coal gasifier experiments, 100kg/hr(2ton/day) fixed bed gasifier was design and constructed. The pilot scale woody biomass gasification system consisted of feeding system, fixed bed gasifier with rotary stoker, oxidant feeding system, preheater, gravity fine particle collector, heat exchanger for syngas cooling, ID fan, and cooling tower. To monitor gasification reaction conditions, IR analyzer and data acquisition system was equipped. At the 5 times gasification experiments, the calorific value of syngas was 1,100~1,500 kcal/Nm3. At the gas engine experiments by using syngas, engine operation was stable when CO/H2 ratio was lower than 1. Because the calorific value might be relatively low, the injection volume of engine had to increase. Compared with LPG, the maximum combustion pressure was lower than 5bar. By using previous experimental results 20kw gas engine was equipped and tested.