Ash-agglomerating Gasification of Coal in a Spouted Bed

Nippon Kokan K. K. is developing a new coal gasification process for high coal conversion with low oxygen consumption. The process is primarily composed of a spouted bed coal gasifier and a recycled fine char gasifier. Mixtures of oxygen and steam are used to gasify both coal and char fines. Gases from the char fines gasifier flow upward through a throat of the spouted bed to fluidize coal particles. It is necessary to discharge the accumulated ashes in the gasifier. A part of ashes are agglomerated and dropped through the throat. Other part are fused as slags and withdrawn from the char gasifier.At the first 'step of the study, a spouted bed gasifier has been operated for 100kg /hr of coal feed with Australian coal Hoskisson. The agglomerated ashes were suc- cessfully separated from the spouted bed of coal particles under the conditions where the bed temperature was higher than 1050°C and the steam/O2 mol ratio of injecting gas was less than 2.0. Char fines elutriated from the spouted bed gasifier were stored for gasification tests at the 2nd stage of the study. Tests of the integrated processwill be conducted at 3rd step of the study.