INFLUENCE AIR FACTOR AGAINST OPERATING PARAMETERS OF

Research and development on fluidized-bed gasification of biomass has been initiated by Yayasan Dian Desa collaboration with NEDO (New Energy and Industrial Technology Development Organization of Japan) starting from small scale (2000–2003), bench–scale tests (2004–2005) and pilot–plant (2006–2009). Since 2006, a cooperative research and development on fluidized–bed gasification of biomass established and agreed between the BPP Teknologi, Yayasan Dian Desa and NEDO to investigate the influence of the air factor on other gasifier operation parameters: bed temperature, gas calorific value and gasifier cold efficiency. The experiments were carried out with the following kinds of biomass: rice husk, sawdust, sugarcane bagasse and spent coffee grounds. The relationship between the gasifier cold efficiency and air factor shows that the curves for rice husk and sawdust have a maximum; for bagasse the relationship is decreasing because of intensive elutriation; for spent coffee grounds due to feeder limitations, it was not possible to feed the biomass flow corresponding to air factor values greater than 0.2. The low efficiency values are a consequence of the lack of thermal insulation in the gasifier freeboard zone