Numerical Simulation on Tube Bundle Demister and Development of High Efficiency Demister

doi:10.11930/j.issn.1004-9649.201706151

Abstract

Abstract: The computational fluid dynamics (CFD) method is used to simulate numerically the two-phase gas-liquid flow in tube bundle demister of wet flue gas desulfurization (WFGD) system for ultra-low dust emission. The double tube structure is introduced into the tube bundle demister. In addition, by modifying the parameters of the tube structure and the blade structure, the effects of structural parameters of the tube bundle demister on demisting efficiency and pressure loss are investigated. The results show that the double tube structure with multistage-series can effectively improve the demisting efficiency, especially for small droplets. The variation of outlet angle, leaf length and leaf number of curvilinear blade have significant impacts on the efficiency of fog removal and pressure drop. On this basis, three types of high-efficiency tube bundle demister are further proposed and then verified by virtue of cold test bench, with one of the optimized prototype applied in the retrofit of the demister of 300 MW power plant. The operation results exhibited satisfactory performance with the mass concentration of soot emission lower than 5 mg/m³(dry base, 6%O₂) under 50%~100% unit load while the max resistance below 300 Pa under full load operation.

Key words: tube bundle demister, numerical simulation, flue gas desulfurization, demisting efficiency, dust ultra-low emission

CLC Number:

X511
TM621.9

QIU Guizhi, ZHANG Zhigang, SONG Yin, GUO Tingting, WANG Haigang, JIA Jia, WANG Heqi. Numerical Simulation on Tube Bundle Demister and Development of High Efficiency Demister[J]. Electric Power, 2018, 51(5): 134-140.

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URL: https://www.electricpower.com.cn/EN/10.11930/j.issn.1004-9649.201706151

https://www.electricpower.com.cn/EN/Y2018/V51/I5/134

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