旁路蒸发塔氯离子迁移模型及固态蒸发产物利用探讨  

Discussions on chloride ion migration model and solid evaporation products utilization in bypass evaporator

作　　者：余子炎[1] 刘道宽 张富峰[1] 曲保忠 乔琳 马双忱[2] YU Ziyan;LIU Daokuan;ZHANG Fufeng;QU Baozhong;QIAO Lin;MA Shuangchen(Guangdong Honghaiwan Power Generation Company Limited,Shanwei 516623,China;Department of Environmental Science and Engineering,North China Electric Power University,Baoding 071003,China)

机构地区：[1]广东红海湾发电有限公司,广东汕尾516623 [2]华北电力大学环境科学与工程系,河北保定071003

出　　处：《热力发电》2021年第10期155-163,共9页Thermal Power Generation

摘　　要：目前,国家鼓励采用烟气蒸发技术处理燃煤电厂脱硫废水以实现废水零排放。旁路蒸发塔工艺使用300℃以上热烟气干燥废水,废水中含有较高浓度的Cl^(-),蒸发过程中一部分Cl^(-)生成氯化氢进入气相,剩余Cl^(-)与其他离子形成结晶盐即固态蒸发产物,其与粉煤灰混合可能会导致Cl^(-)超标,影响粉煤灰的综合利用。使用状态方程法计算Cl^(-)气固相间分配量,建立蒸发塔的Cl^(-)迁移模型。结合某电厂实际数据,利用模型计算出固态蒸发产物的含氯量,结果表明:固态蒸发产物不属于危险废物,但含氯量较高,会对利用固态蒸发产物生产建材产品产生影响,推荐使用高温陶瓷过滤器或小型电除尘器单独收集固态蒸发产物,并可将收集的固态蒸发产物应用于生产混凝土、免烧结砖,或矿井、公路路基、台背等回填工程中。At present,the state encourages the use of flue gas evaporation technology to treat desulfurization wastewater from coal-fired power plants to achieve the goal of zero discharge of wastewater.The bypass evaporation tower process applies hot flue gas above 300℃ to dry the wastewater.The wastewater contains a high concentration of chloride ions(Cl^(-)).During the evaporation process,a part of Cl^(-)generates hydrogen chloride which then enters the gas phase.The remaining Cl^(-)forms a crystalline salt with other ions,namely the solid evaporation product.Its mixing with fly ash may cause the Cl^(-)concentration exceeds the standard and affect the comprehensive utilization of fly ash.The equation of state method is employed to calculate the distribution of Cl-between gas and solid phase.The chloride ion migration model of the evaporation tower is established.Combined with the actual data of a power plant in Guangdong,the model is used to calculate the chlorine content of the solid evaporation product.The results show that,the solid evaporation products are not hazardous wastes.However,due to the high chlorine content,it will have an impact on the production of building materials using solid evaporation products.It is recommended to use a high-temperature ceramic filter or a small electric precipitator to collect the solid evaporation products separately.The collected solid evaporation products are used in the production of concrete,non-burning bricks,or backfilling projects such as mines,highway subgrades and abutments.

关 键 词：旁路蒸发 蒸发塔技术 氯离子迁移 产物特性 产物收集 资源化利用 

分 类 号：X773[环境科学与工程—环境工程]