Small-Scale Toroidal Fluidized Bed Gasification System: Development and Experimental Aspects

This article deals with system development and experimental aspects of a small-scale toroidal fluidized bed gasifier (TFBG) using sawdust feedstock (carpentry waste) with average particle size of 4.18 mm. The reactor and its accessories are designed and constructed. The experiments have been performed to highlight the influence of equivalence ratio on performance parameters (i.e., reaction temperatures, gas yield, gas composition, heating value, and cold gasification efficiency). For variation of equivalence ratio from 0.181 to 0.273 (average basis), the maximum temperature increase from 1015 to 1036 K, combustibles components CO, H2, and CH4 decrease from 16% to 14.9%, 16.3% to 15.3%, and 3.5% to 2.3%, respectively, and consequently, lower heating value (LHV) decreases from 5.454 to 4.716 MJ kg−1. On qualitative basis, the maximum cold gasification efficiency is observed to be 74% at equivalence ratio of 0.273, which is considerably higher than fixed bed gasification for sawdust. The overall uncertainty of experimental data is worked out to be ±3.41% (i.e., ≤5% within 95% confidence level).