晶种法多效蒸发在烧结烟气脱硫废水零排放中的应用  

Application of crystal seed multi-effect evaporation in zero discharge of sintering flue gas desulfurization wastewater

作　　者：邓毅 梁全勋 徐勤 李娜 DENG Yi;LIANG Quanxun;XU Qin;LI Na(Dongfang Boiler Co.,Ltd.,Zigong 643001,China)

机构地区：[1]东方电气集团东方锅炉股份有限公司,四川1自贡643001

出　　处：《技术与市场》2023年第8期1-5,共5页Technology and Market

摘　　要：钢铁厂烧结烟气石灰石-石膏脱硫废水属于典型的高盐、高硬度、难处理工业废水,成分复杂且水质变化大,除具有常规电厂脱硫废水氯离子含量高、硫酸钙含量高等特点外,还具有较高的氟离子及氨氮含量。传统处理方法在烧结烟气脱硫废水的处理中,都具有投资成本高、软化加药运行成本高、系统运维操作难度大且可靠性差等问题。通过实际工程验证,采用“混凝沉淀预处理+晶种法三效蒸发浓缩+浓水喷洒烧结矿+产水蒸氨”的工艺路线,很好地解决了烧结烟气脱硫废水处理的难题,实现了脱硫废水零排放。同时,充分利用浓水中的氯化钙成分以降低烧结矿的低温还原粉化率,产水经蒸氨后也可制成氨水,作为烟气脱硝还原剂,从而对脱硫废水进行了充分的资源化利用。在晶种法三效蒸发浓缩系统中,通过采用蒸汽喷射器(TVC),抽取部分二次蒸汽,与动力蒸汽混合后作为系统热源,可最大程度降低系统的能耗。Limestone-gypsum FGD desulfurization wastewater for sintering exhaust flue gas is a typical hard-treated indus-trial wastewater with high salt,high hardness,high chlorine ion content,high calcium sulfate content,high fluorine ion con-tent,and ammonia nitrogen content.The traditional treatment methods have many problems,such as high investment costs,high operation costs of softening dosing,and difficulty in operation and maintenance.Through practical engineering verifica-tion,the following process is a suitable solution to the above problems:coagulation precipitation pretreatment,crystal seed three-effect evaporation,concentrated water spray to sintering ore with high temperature,and ammonia stripping from produc-tion water of evaporation.In this process,the concentrated water,which is rich in calcium chloride,is fully utilized to reduce the low temperature reduction degradation rate of sinter,and the ammonia stripped from produced water can be made into ammonia water,which is used as a denitration-reducing agent of flue gas.In the crystal seed three-effect evaporation system,the TVC steam ejector is adopted to reduce energy consumption.

关 键 词：晶种法多效蒸发 烧结烟气 脱硫废水零排放 TVC 

分 类 号：X757[环境科学与工程—环境工程]