The Oxygen Staged Entrained Flow (OSEF) Gasifier is a product of the research and development work at Tsinghua University’s Institute of Thermal Engineering.
By 2003, a two-stage, entrained-flow gasifier had been developed and the Shanxi Fengxi Fertilizer Group had constructed two industrial producing facilities using the gasifier with a feed stock input for each facility of 500 t/d coal. A second, follow-on phase in the development of the Tsinghua Gasifier was initiated in 2005, in which R&D activity focused on utilization of coal-water slurry feedstocks and water cooling wall technology. The resulting 2nd generation gasifier was put into operation, again in Fengxi, in August 2011.
Both types of Tsinghua gasifiers, (i.e. first generation available since 2003, second generation available in 2011) have been commercialized.
The concept of the Tsinghua OSEF Gasifier includes five coal transformation/reaction stages including:
Staged introduction of oxygen into the gasifier is utilized, which is reported to improve the working condition of the main burner (extending burner lifetime), the axial temperature and the temperature field as well as coal adaptability.
The second generation Tsinghua gasifiers utilize coal slurry feed in a membrane wall gasifier, which offer a number of significant advantages including:
Demonstration and Commercialization
In China, six facilities utilize the first generation gasifier and seven facilities utilize the second generation unit as of about 2012. In each case, the gasifier was initially placed in operation by the Fengxi Fertilizer Group, Linyl Branch in Yunching, Shanxi Province. More recent information from the last year on the newer generation water-cooled gasifier projects moving forward evidences lively growth in the use of this gasifier technology, and also some diversification away from the fertilizer industry:
In fact, it was noted that in 2013, 16 projects were licensed using Tsinghua gasifier technology, more than the total of all other gasification providers in China. Refer to the China Gasification Database for further information.