Utilization of clean coal is challenging enough that must be solved with extensive method. The current study of sub-bitumius coal from south Kalimantan is utilized to produce gas fuel with gasification process using downdraft gasifier. Gasification process was conducted at condition different air flow rate i.e112.81 lpm,154.26, 229.9lpm, 293.57lpm, and 365.78 lpm. The results of experiment shown gasification could produces combustible gas (CO, CH4,H2) continuously during1.5 hours operation on each condition of gasification air flow rate and increasing air flow rate will increase temperature inside reactor and gas flow rate. Increasing air flow rate to 297.57 lpm will increase CO content, gasification efficiency and flame length.
Flame conditionat difference air flow(a) 112,81 lpm ; (b) 154,26 lpm; (c) 293,57 lpm; (d) 365, 78 (lpm)