钠碱法脱硫循环液pH值的自动控制与效益影响

Automatic Control of pH Value for Sodium Alkali Desulfurization Circulation Liquid and Benefits

钠碱法脱硫工艺先进,技术成熟,是国内化工行业常用的脱硫方法之一。结合公司硫酸尾气钠碱法脱硫系统,介绍了脱硫机理与工艺流程,分析了吸收循环液pH值变化的因素及其影响。介绍了通过自动化控制改造以控制吸收塔循环液pH值的设计方案及控制效果。生产实践证明,通过对吸收循环液的pH值自动化控制,在保证SO 2超低排放的基础上大量降低碱液的消耗量,即获得经济效益又获得环境效益。

The sodium alkali desulfurization is a proven and well⁃established desulfurization process commonly used in the chemical industry in China.Based on the sodium alkali desulfurization system for sulfuric acid tailgas of the company,The desulfurization mechanism and process flow are outlined,the factors and influences of pH value variations are analyzed in the absorption circulation liquid.The design scheme and control effect are described for pH value control in the circulation liquid of the absorption tower through improvement of the automatic control.The production practice shows that,through automatic control of pH value in the absorption circulation liquid,the alkali liquid consumption is reduced significantly,while the SO2 ultra⁃low emission is ensured,which offers both economic benefit and environmental benefit.