To satisfy the design requirement that in coal pyrolysis moving bed reactor the flow structure should be in mass flow pattern, the influences of insert settings on the flow behavior of granular assembly in moving bed were investigated by conducting discrete element simulations with three types of insert with different geometrical structures were considered: disk-shape, triangle-shape and splayed-shape. The simulation results showed that for disk-shape and triangle-shape inserts, the flowing zone width was approximately equal to the sum of the flowing zone width of the moving bed without insert and the maximum projection size of insert in the flowing direction. As to the splayed-shape insert, depending on its vertical position and the distance between the two wings there existed three types of flow structure. The flowing zone width achieved the maximum value when the distance between the two wings was equal to the outlet size. For the investigated conditions, there existed optimal vertical position(~30d) and the distance of wings (~20d) (d was diameter of the largest particle) under which condition the flow rate is notably larger than that for moving bed without insert.
Qiang LIU Jinglin SU Jinhui ZHAN Guangwen XU Xiaoxing LIU
. Discrete Modeling of Effect of Insert on Discharge Dynamics of Granular Material in Moving Bed[J]. The Chinese Journal of Process Engineering, 2017
, 17(6)
: 1163
-1169
.
DOI: 10.12034/j.issn.1009-606X.217171
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