Exergy Analysis of Self-Bed Feedstock in Rice Husk Bubbling Fluidized Bed Gasifier

Abstract

This study will use the result simulation of bubbling fluidized bed gasifier (BFBG) in CFD to know the value of producer gas (CO2, CO, H2, CH4, O2, and N2). Commonly in BFBG silica sand is used as bed material in the gasification process but in this study silica sand or bed material is absented in the gasification process. The energy and exergy analysis will be evaluated in this study to indicate the performance of BFBG without bed material. In this study rice husk is used as a feedstock with feed rate 0.2 kg/s, and air is used as medium gasification in the range of ER (equivalence ratio) between 0.24 to 0.45. Variation of ER affect the value of energy and exergy, where the higher ER applied the higher exergy destruction that occur and decrease the efficiency of exergy. It was calculated that the best efficiency was obtained when the value of ER is 0.24, with the total value of energy and exergy are 2544 and 2335 kJ per kg biomass, sequentially.