电站锅炉给水pH值异常原因探讨

Discussion on Abnormal pH Value of Boiler Feed Water in a Power Plant

某公司一电站锅炉给水pH值在各项常规水质数据正常情况下持续异常,为保证锅炉水pH值合格,单一的磷酸三钠配方无法满足要求,需要增加氢氧化钠配合调整。通过对工艺和水质等方面的排查后,确定锅炉给水pH值持续异常的原因是制备二级除盐水的原水发生变化,即新增淡化海水原水种类,淡化海水水温偏高,导致系统溶解二氧化碳量增加,最终导致锅炉给水pH值偏低。

As the water pH value of the power station boiler in a company was continuously abnormal under the normal condition of all water quality data,the single formula of trisodium phosphate could no longer meet the requirements for qualified boiler water pH value,and it was necessary to add sodium hydroxide to improve water quality.By checking the process and water quality,it was determined that the reason for the continuous abnormal pH value of boiler feed water was the changed raw water for preparing secondary desalinated water-adding new raw water from desalinated seawater.The water temperature of desalinated seawater was too high,which led to the increase of dissolved carbon dioxide in the system,and finally resulted in the low pH value of boiler feed water.A solution was presented in this paper to address the boiler feed water pH abnormal problem.