Rheology and Transportation Characteristics of a Coal Gasification Feed Slurry

摘要

Coal-light oil slurry technology for high-pressure reactor feed has been in use at the HYGAS pilot plant. This paper investigates the slurry-pumping characteristics for the alternative water-based feed system with Eastern coals. The water-based slurry transport system could originate at the mine and involve wet crushing, wet sizing, submerged particle oxidation of coal to reduce the agglomerating property of Eastern coals, and mechanical dewatering operations before feeding to the high-pressure reactor. Rheological and pumping characteristics of an Illinois No. 6 run-of-mine coal are examined for a typical gasifier feed-size consist of -14 mesh, with 10% less than 100 mesh as a water and toluene slurry. The information developed here is useful for design considerations of a gasification slurry-fed reactor, especially for the low-pressure, wet-handling, feed preparation portion. The vertical lift and pressurization to high pressures would be controlled more by the high pressure pump design rather than slurry characteristics. However, slurry characteristics are very important in the upstream feed-preparation steps. For a continuous flow operation, these steps involve mixing various-sized feeds and concentrations from various crushers and screens. Understanding the limits of pumping, aids in designing an efficient operation and managing feed delivery, water requirements, and system wear. (ERA citation 05:025138)