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Title: U-GAS process

Conference ·
OSTI ID:5324454

The Institute of Gas Technology (IGT) has developed an advanced coal gasification process. The U-GAS process has been extensively tested in a pilot plant to firmly establish process feasibility and provide a large data base for scale-up and design of the first commercial plant. The U-GAS process is considered to be one of the more flexible, efficient, and economical coal gasification technologies developed in the US during the last decade. The U-GAS technology is presently available for licensing from GDC, Inc., a wholly-owned subsidiary of IGT. The U-GAS process accomplishes four important functions in a single-stage, fluidized-bed gasifier: It decakes coal, devolatilizes coal, gasifies coal, and agglomerates and separates ash from char. Simultaneously with coal gasification, the ash is agglomerated into spherical particles and separated from the bed. Part of the fluidizing gas enters the gasifier through a sloping grid. The remaining gas flows upward at a high velocity through the ash agglomerating device and forms a hot zone within the fluidized bed. High-ash-content particles agglomerate under these conditions and grow into larger and heavier particles. Agglomerates grow in size until they can be selectively separated and discharged from the bed into water-filled ash hoppers where they are withdrawn as a slurry. In this manner, the fluidized bed achieves the same low level of carbon losses in the discharge ash generally associated with the ash-slagging type of gasifier. Coal fines elutriated from the fluidized bed are collected in two external cyclones. Fines from the first cyclone are returned to the bed and fines from the second cyclone are returned to the ash agglomerating zone, where they are gasified, and the ash agglomerated with bed ash. The raw product gas is virtually free of tar and oils, thus simplifying ensuing heat recovery and purification steps.

Research Organization:
GDC, Inc., Chicago, IL (USA); Institute of Gas Technology, Chicago, IL (USA)
OSTI ID:
5324454
Report Number(s):
CONF-820247-1; ON: DE82902692
Resource Relation:
Conference: Thailand-United States oil shale/lignite symposium, Bangkok, Thailand, 1 Feb 1982
Country of Publication:
United States
Language:
English