多晶硅生产冷却循环水系统及水质控制技术

Cooling circulating water system for polysilicon production and the water quality control technologies

多晶硅生产过程的冷却循环水系统主要用来为物料降温,一般分为开式循环水系统和闭式循环水系统。开式循环水系统主要工艺部件是开放式的,补水来源一般为工业软化水,循环水在运行过程中会发生CO2含量降低、碱度增加、pH值升高、浊度增加等情况,需要对冷却水的指标进行监测和控制,并选择适合的水处理药剂进行投加。闭式循环水系统为密闭系统,循环用水要求较严,相较于开式循环水系统,组成部件更加复杂,但水质控制较为容易。目前较新的水质控制技术包括无磷配方除垢剂、电子除垢仪和新型防垢防腐蚀合金材料,这些新技术的使用可以减少后期成本投入,并且能减少甚至消除冷却塔及设备的清洗频次,在新厂建设及技改项目中,应尽量选用。

The cooling circulating water system in the polysilicon production process is mainly used to cool the material,and is generally divided into an open circulating water system and a closed circulating water system.The main process components of the open circulating water system are open,and the source of supplementary water is generally industrial softened water.During the operation of circulating water,CO2 content reduction,alkalinity increase,pH value increase,and turbidity increase will occur.It is necessary to monitor and control the indicators of cooling water and select suitable water treatment chemicals for dosing.The closed circulating water system is a closed system,and the requirements for circulating water are stricter.Compared with the open circulating water system,the components are more complicated,but the water quality control is easier.At present,the newer water quality control technologies include phosphorus-free descaling agent,electronic descaler and new anti-scale and anti-corrosion alloy materials.These new technologies can reduce subsequent cost input,and can reduce or even eliminate the cleaning of cooling towers and equipment.In new plant construction and technological transformation projects,the new technologies should be selected as far as possible.