超超临界机组酸洗废水零排放处理工艺研究及应用

Research of chemical cleaning wastewater zero-discharge treating process for ultra-supercritical units and its application

锅炉酸洗废水具有排放量大、污染物浓度高和处理难度极大的特点。为实现酸洗废水处理后复用,不外排,分析了河源电厂2×600 MW超超临界机组酸洗废水成份,进行了小型模拟处理试验,探索了降低废水中金属离子含量、COD和浊度的方法。根据试验结果,采用稀释、p H调整、曝气、絮凝、沉淀及机械过滤的方法对锅炉酸洗废水进行处理,处理后的清水作为脱硫系统的工艺补充水。脱硫系统排出的废水采用蒸发结晶工艺进行处理,处理后的冷凝水作为冷却塔补充水回收利用,最终实现零排放,可为火电厂酸洗废水的处理利用提供参考。

The chemical cleaning wastewater for boiler is great emissions with high pol utant concentrations, and is difficult to be treated.In order to achieve the wastewater being reuse after treatment, basing on 2 ×600 MW ultra-supercritical units at Heyuan Power Plant, the wastewater compositions were analyzed,and simulation tests were taken how to reduce heavy metal ions, COD and suspended materials in the wastewater.Fol owing the test results, the cleaning wastewater was treated by dilution, pH adjustment, aeration, flocculation, sedi-mentation and mechanical filtration methods, and was reused as wet FGD process water.Then the desulfuriza-tion wastewater was treated by evaporation-crystal ization process, and the condensate water was recycled to the cooling tower, there were no discharges for the wastewater.The article can provide a reference to the ther-mal power plant how to treat the chemical cleaning wastewater with ZLD way.