Simulation on mixing granular materials in screw conveyor

QI Huabiao1 XU Ji1 SONG Wenli1 GE Wei1,2

(1.State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China 100190)
(2.School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing, China 100049)

【Abstract】Flowing and mixing granular materials of two different sizes and densities in an industrial-scale screw conveyor were studied by computer simulation using the discrete element method (DEM). The quantitative analysis results by the Lacey M showed that the mixing performance of the screw conveyor was dependent strongly on operational conditions and structural dimensions. Both screw rotating speed and material feeding rate had dominant effects on mixing efficiency, followed by granular material sizes and screw pitch in the mixing region. To reduce energy consumption and improve mixing performance in production, reasonable operation parameters of screw conveyors could be selected according to these findings.

【Keywords】 granular material; discrete element method; screw conveyor; mixing mechanism; large-scale simulation;

【DOI】

【Funds】 “Strategic Priority Research Program” of the Chinese Academy of Sciences (XDA07080000) Key Research Program of Frontier Science, CAS (QYZDJ-SSW-JSC029) CAS Interdisciplinary Innovation Team National Natural Science Foundation of China (91434201)

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(Translated by KANG GD)

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This Article

ISSN:0438-1157

CN: 11-1946/TQ

Vol 69, No. 01, Pages 371-380

January 2018

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Article Outline

Abstract

  • Introduction
  • 1 Simulation method
  • 2 Simulation conditions
  • 3 Measurement method
  • 4 Result analysis
  • 5 Conclusions
  • Symbol description
  • References