锅炉给水系统腐蚀原因分析

凝结水与锅炉补给水中的CO2是给水系统腐蚀的根本原因所在，加氨处理是防止该腐蚀最常用的方法；在给水加氨、且同时存在CO2、有机物（CH3COOH）的情况下，文章推导了给水系统pH值的精确计算方程式，根据300MW、600MW机组给水系统的升温情况，计算出了高温下给水pH值的变化值，并以图示出计算结果；同时简要分析了给水系统的腐蚀原因，提出了相应的应对措施.

ANALYSIS OF CORROSION CASE IN A BOILER FEEDWATER SYSTEM

The corrosion damages in a boiler feedwater system are caused by CO 2 came from condensate and boiler make-up water, the general anti-corrosion measure is to adjust pH value of the water to about 9 0 with ammonia.When ammonia?carbon dioxide(CO 2)?organic matter(typical as CH 3COOH) coexist,an exact expression for feedwater pH value calculation was obtained by chemical equilibrium equation.According to the relevant parameters of feedwater heating for 300MW and 600MW generating units,the exact pH values may be deduced and then showed as graphics.In the meanwhile,the cause for corrosion in feedwater system is analysed briefly,thereby the suitable prevention measure is also given.