火电行业脱硫废水除垢技术小试实验研究

A Small Experimental Study on Descaling with Desulfurization Wastewater from the Thermal Power Industry

本文以新疆某火力发电厂脱硫废水为研究对象,通过实验室软化预处理小试研究,为火电行业脱硫废水零排放提供理论支持和数据支撑。研究结果表明:在该火电厂脱硫废水软化预处理过程中沉淀剂(NaOH/Na2CO3)最佳投加顺序为先投加NaOH沉淀Mg^2+,后加Na2CO3沉淀Ca^2+;最佳投加量为n(NaOH)/n(Mg^2+)=6:1,n(Na2CO3)/n(Ca^2+)=1:1,该脱硫废水中Ca^2+/Mg^2+的去除率可以达到99%以上,脱硫废水硬度(以CaCO3计)低于450mg/L,为火电脱硫废水后续处理提供水质保证。

This paper provides theoretical support and data support for zero discharge of desulfurization wastewater from the thermal power industry through a small laboratory study of softening pretreatment of desulfurization wastewater from a thermal power plant in Xinjiang.Study results show that:the best dosing sequence of precipitants (NaOH/Na2CO3) in the softening pretreatment process of the desulfurization wastewater from the thermal power plant is first NaOH for precipitation of Mg^2+ and then Na2CO3 for precipitation of Ca^2+;the best dosage is n(NaOH)/n(Mg^2+)=6:1,n(Na2CO3)/n(Ca^2+)=1:1.Under these conditions,the removal rate of Ca^2+/Mg^2+ in the desulfurization wastewater can be more than 99%,and the hardness of the desulfurization wastewater (by CaCO3) is less than 450 mg/L.