燃煤发电厂的深度节水与废水零排放

Deep Water Saving and Zero Liquid Dischargeincoal-Fired Power Plant

火力发电厂普遍面临在保证经济性的前提下实现废水零排放的挑战。本文以浙能典型电厂(长兴、台州、嘉兴)为案例,从分析火电厂各类废水产生的源头和现有废水系统流程设计上存在的问题出发,经过对全厂水平衡分析,提出燃煤发电厂零排放系统宜从源头废水减量开始,以消减末端高盐废水为目标,将废水的分类收集,逐级浓缩减量和资源化,结合调整脱硫运行方式和工艺水补水,最后末端高盐废水采用烟气余热固化处理,形成了以烟气干化为核心的废水零排放技术体系。最终实现经济、可靠的深度节水和废水零排放。本文在此基础上还提出按照盐分建立分级实时信息监测水网,对未来实现对各水(废水)系统运行的精准预测和诊断目的。

Thermal power plants are facing challenge of zero liquid discharge under the premise of economy,reliability and stability.Taking typical power plants in Zheneng(Changxing,Taizhou and Jiaxing)as examples,analysis the source of various wastewater in thermal power plants and the existing problems in the design of wastewater system process,and through the water balance of the whole plant,this paper puts forward that zerodischarge system should start with reduction of wastewater from the source to reduce the high salt wastewater production at the end.Different waste water should be classified and collected separatly,low salinitywater is reused,high salinity wastewate is reduced,and meanwhile the water replenishment and operation mode of the desulfurization process are optimized.Finally,It is recommended that the high temperature flue gas drying process be used to solidify the terminal high salinity wastewater directly..On the basis of this,this paper also proposes to establish a water network based on the real-time information of the salt classification,and to realize the accurate prediction and diagnosis of the operation of each water(wastewater)system.