In order to control the Fe3+ corrosion during boiler chemical cleaning

the corrosion of Fe3+ with different concentration on material SA-213 used in boiler was investigated with electrochemical method and corrosion weight loss method in static state

taking the actual boiler chemical cleaning liquid as the test liquid.In addition

the influence of operating conditions such as adding method of reductants in chemical cleaning process was studied.Results show that

3+ has an obvious corrosion on the metal substrate

and with the increasing of Fe3+ concentration

a sharp increment of corrosion rate is observed.Adding proper amount of reductants can efficiently restrain the rise of Fe3+ concentration.The reductants should be added in batches according to the concentration of 3+ in cleaning liquid.Besides

to inhibit the transformation of Fe2+

the authors suggest preventing the air from entering into the system

as well as ensuring a certain residual acid concentration and a low level value of pH in liquid.