600MW燃煤机组湿法脱硫系统节能运行的优化研究

Optimization Study on the Energy Conservation Operation of Wet Desulphurization System of a Domestic 600 MW Coal-fired Unit

本文通过在实验室进行添加剂筛选实验,使石灰石活性提高最多的是己二酸。基于在国内某电厂600MW机组上进行添加己二酸的工程应用试验,得出投加己二酸前后的脱硫效率、液气比和石灰石利用率的变化。利用添加剂,在保证脱硫效率的前提下,改变浆液循环泵的组合方式,减少电耗,以达到节能运行的目的。研究结果显示通过添加己二酸,脱硫效率可提升2%~5%。投加己二酸前后,系统钙硫比由1.002提高至1.034,钙硫比提高3%,即石灰石的利用率提高了3%。己二酸的投加强化了脱硫反应的传质过程,可以缓冲pH值的波动,有利于加强系统的操作灵活性和运行稳定性。

The additive screening test for improving the limestone activity identified adipic acid as the best organic acid that enhances the limestone activity the most. By adding adipic acid to a domestic 600 MW unit,the changes in the desulfurization efficiency,liquid-gas ratio and the utilization ratio of limestone were obtained. For the same desulphurization efficiency,adding the adipic acid and adjusting the slurry circulating pump combinations could save the energy consumption. The results showed that when the mass ratio between adipic acid and limestone was 0. 25%,the desulfurization efficiency is improved by 2% ~ 5%. After adding the adipic acid,the system calcium sulfur ratio increases from 1. 002 to 1. 034,or the calcium sulfur ratio increases by 3%,namely limestone utilization ratio increases by 3%. The organic acids enhance the desulfurization reaction and mass transfer process,and can buffer pH fluctuations,beneficial in improving the operation flexibility and stability of the desulfurization system.