调相机外冷水系统结垢分析及改进研究

Analysis and Improvement for Scaling of External Cooling Water System

某±800kV换流站300Mvar调相机组年度检修时,发现外冷水系统出现严重结垢、冷却器堵塞、冷却水池藻类滋生等现象,影响设备安全运行。通过对外冷水、补充水(城市自来水)的水质进行检测,并对外冷水所用的阻垢缓蚀剂性能进行评价,发现外冷水和补充水的硬度和碱度偏高,阻垢缓蚀剂与外冷水水质不匹配,抑制结垢效果不佳,存在明显结垢倾向,同时杀菌灭藻剂的加药方式不合理造成微生物产生抗药性,导致藻类微生物滋生严重。通过外冷水阻垢缓蚀剂筛选和性能评价,筛选出高效阻垢缓蚀剂,并应用于外冷水的处理,同时改变杀菌灭藻剂的加药方式后,外冷水系统水质大幅提升,结垢、腐蚀和藻类滋生情况大幅改善。进而提出外冷水系统的深度处理措施,进一步提高外冷水水质,减少药剂的使用量。

During the annual maintenance of 300 Mvar synchronous condenser unit in a±800 kV converter station,it was found that the external cooling water system had severe scaling,cooler blockage,and algae growth,which affected the safe operation of the equipment.Through testing the water quality of external cooling water and supplementary water(urban tap water),and evaluating the performance of scale and corrosion inhibitor used in external cooling water,it is found that the hardness and alkalinity of external cooling water and supplementary water are high,the scale and corrosion inhibitor don’t match the water quality of external cooling water,and the scaling inhibition effect is not good,and there is an obvious scaling tendency.The unreasonable way of dosing bactericidal and algaecide leads to resistance of microorganisms and serious breeding of algae microorganisms.Through the screening and performance evaluation of scale and corrosion inhibitors of external cooling water,high-efficiency scale and corrosion inhibitors were screened and applied to the treatment of external cooling water.At the same time,after changing the dosing method of bactericidal and algal agents,the water quality of the external cooling water system was significantly improved,and the scaling,corrosion,and algal growth conditions were greatly improved.Advanced treatment measures of external cooling water system are proposed simultaneously to further improve the water quality of external cooling water and reduce the use of chemicals.