Gasification of a typical low-rank coal in 65MW th KEDA® circulating fluidized-bed gasifier

The KEDA® circulating fluidized-bed (KEDA®CFB) gasifier is a high-temperature air-blown circulating fluidized bed developed by KEDA (ANHUI) Clean Energy Co., Ltd to produce clean industrial gas. This project describes the design and the initial operating results of using low-rank coal to produce industrial fuel gas in a 65MW th KEDA®CFB industrial-scale plant with a feeding rate of 13 ton/hr. The gasification process was carried out at an ambient pressure and temperatures at 980 ± 10 °C. A long-term stable operation was achieved for more than 20 days. Cold gas efficiency could reach 73% with a gas high heating value of 5.89MJ/Nm 3 at a steam-to-coal ratio of 0.38 and an equivalence ratio of 0.3. During the stable operation, it was also observed that the operational bed temperature has to be kept under the residual ash fusion temperatures (AFTs) to avoid aggregation and defluidization.