Research on Scale Problem of Single Tower with Dual Loop Desulfurization System

doi:10.11930/j.issn.1004-9649.201706032

Abstract

Abstract: Single tower with dual loop desulfurization system has been widely used in the retrofit of ultra-low emission. However, severe scale problem has taken place in the top slurry spray layer under the slurry collecting bowl in some coal-fired power plants with some nozzle and branch pipe of slurry spray layer also blocked. In this paper, two coal-fired power plants denoted by A and B are taken as examples. Through the examination of the on-site equipment and system, the analysis on the composition of scale sample in laboratory, and the numerical simulation on the flow field distribution of the desulfurization tower using CFD software, it is concluded that the scale problems are related to the size of slurry collecting bowl, nearby flow distribution, the volume of the slurry tank and pH of the slurry. In order to avoid the scale problem, starting from desulfurization tower design, operation parameters control and equipment maintenance should be enforced strictly. In power plant B, the one-way nozzles of the top slurry spray layer under the slurry collecting bowl had been replaced with two-way nozzles and the operation parameters have been also improved. Eventually, the scale problem of power plant B was solved successfully.

Key words: coal-fired power plants, ultra-low emission, desulfurization system, single tower with dual loop, slurry collecting bowl, scale problem, occlusion

CLC Number:

TM621
X511

DONG Ruifeng, CHEN Haojun, WANG Fengtao, WU Wenlong. Research on Scale Problem of Single Tower with Dual Loop Desulfurization System[J]. Electric Power, 2018, 51(4): 149-154.

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URL: https://www.electricpower.com.cn/EN/10.11930/j.issn.1004-9649.201706032

https://www.electricpower.com.cn/EN/Y2018/V51/I4/149

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