高炉煤气干法除尘喷碱塔系统的分析与优化

Analysis and optimization of blast furnace gas dry dedusting and alkali spraying tower system

针对已在迁钢2号高炉成功应用的高炉煤气干法除尘喷碱塔系统在新建3号高炉应用中出现的煤气冷凝水pH值偏低的问题,对2、3号高炉煤气干法除尘喷碱塔系统的碱液浓度、外排水系统、喷头和碱液泵的运行参数、煤气在喷碱塔内的停留时间以及碱液喷头雾化效果进行了对比分析。结果表明,外排水系统排水不畅和碱液喷头雾化效率低是导致3号高炉煤气冷凝水pH值偏低的主要原因。对外排水系统和碱液喷头进行改造后,3号高炉煤气冷凝水pH值为6~7,这不但防止了管道因高炉煤气冷凝水腐蚀而导致的生产事故,而且降低了系统运行成本。

The dry dedusting alkali spraying tower system of blast furnace gas in No.3 new BF raised the problem of low flue gas condensate pH value,while the same type of system has been worked in No.2 BF of Qian′an Steel Company successfully.According to this phenomenon,the operation characteristics,such as alkali concentration,external drainage system,parameters of nozzles and alkali pumps,the gas residence time in alkali spraying tower and atomization effects of alkali nozzles,were analyzed contrastively.The results showed that the poor capability of the drainage system and the low atomization efficiency of the alkali nozzles were the main reasons for the low pH value of the blast furnace gas condensate.After improving the external drainage system and the alkali nozzles,the gas condensate pH value of No.3 blast furnace was between 6 and 7,which could not only prevent the production accidents caused by the corrosion of the blast furnace gas condensate,but also reduce the system operation cost.