(26a) Study on the Feeding Characteristics of Pulverized Coal for Entrained-Flow Gasification

The characterization of powder flow properties is often required for reliable design and proper operation of industrial processes. For the entrained-flow pulverized coal gasification, coal is always pulverized to a size in the order of 90% < 100 μm diameter to make sure the high efficiency of carbon conversion inside the gasifier. Such kind of powder shows poor flowability and brings challenge for the subsequent hopper discharge and pneumatic conveying processes. In this paper, the flow properties of pulverized coal was firstly characterized by a PT-X powder tester and a FT4 powder rheometer. The flowability of the pulverized coal was determined by kinds of flow criteria, in terms of angle of repose, Hausner Ratio and Jenike flow function etc. Secondly, discharge of pulverized coal from the hopper were studied where the effects of aeration, hopper pressure and aerated gas type were discussed by analyzing the weight-versus-time curve and the pressure-versus-time curve etc. Finally, pressurized pneumatic conveying of pulverized coal was studied in kinds of dense-phase pneumatic conveying systems where the conveying characteristics and flow patterns were discussed. The study of work will provide a value reference for the reliable feeding of pulverized coal for the entrained-flow gasification.