SCI和EI收录∣中国化工学会会刊

Chinese Journal of Chemical Engineering ›› 2020, Vol. 28 ›› Issue (2): 518-525.doi: 10.1016/j.cjche.2019.06.004

• Energy, Resources and Environmental Technology • Previous Articles     Next Articles

Parametric optimization of packed bed for activated coal fly ash waste heat recovery using CFD techniques

Kai Liang1, Saimeng Jin1, Hengzhi Chen1, Jingzheng Ren2, Weifeng Shen1, Shun'an Wei1   

  1. 1 School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China;
    2 Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hong Kong, China
  • Received:2019-04-01 Revised:2019-06-10 Online:2020-02-28 Published:2020-05-21
  • Contact: Weifeng Shen, Shun'an Wei E-mail:shenweifeng@cqu.edu.cn;wsacn@cqu.edu.cn
  • Supported by:
    We greatly acknowledge the financial support provided by the National Key Research and Development Program (No. 2017YFB0603105).

Abstract: Coal fly ash is an industrial solid waste generated from coal preparation during the processing and cleaning of coal for electric power generation. Comprehensive investigation on the reutilization of waste heat of activated coal fly ash is of great economic significance. The method of recovering the waste heat, proposed in this study, is the transfer of heat from activated coal fly ash to gas with the movement of air using the packed bed, providing valuable energy sources for preheating the raw coal fly ash to reduce the overall energy consumption. The investigation is carried on the heat transfer characteristics of gas-solid (activated coal fly ash) phases and air temperature fields of the packed bed under some key conditions via computational fluid dynamics. A two dimensional geometry is utilized to represent key parts of packed bed. The distribution mechanism of the temperature field for gas phase is analyzed based on the transient temperature contours at different times. The results show that the obtained rule of gas-solid heat transfer can effectively evaluate the influences of operating parameters on the air temperature in the packed bed. Simultaneously, it is found that no temperature differences exist in the hot air at the outlet of the packed bed. The investigation provides guidance for the design and optimization of other similar energy recovery apparatuses in industries.

Key words: Coal fly ash, Computational fluid dynamics, Eulerian-Eulerian model, Waste heat recovery, Packed bed