The Institute of Process Engineering developed a technology that can produce middle caloric fuel gas with dual bed reactors, which consists of a transport bed (or riser) combustor and a fluidized bed gasifier. A distinctivefeature of this technology is the isolation of gas production reactions (pyrolysis and gasification) process from char combustion process. Thus the heat for the fuel pyrolysis and gasification reactions in the gasifier can be sustained by the sensible heat of the circulating particles from the combustor by burning the unreacted char. As a result, it is possible to produce middle caloric fuel gas, about 2000 kcal/ Nm3, with air as gasifying reagent. Furthermore, this technology adapts to low-quality coals, including brown coal and long-flame coal with high volatile and water contents and below 20 mm, and can reduce fuel cost by 40% and enhance the gasification efficiency about 20%. A pilot test (1000 t/a) was successfully operated in 2008.