The invention discloses a
chemical cleaning and pre-filming method of a circulating water
system. The method comprises the steps as follows: (1) sterilization and slime stripping:
pollution dischargeand water replenishing are
shut down under the condition that the water quantity of the
system is guaranteed, a non-
oxide sterilization and alga removal agent and a slime stripping agent are added inan
impact manner, the
turbidity falls step by step after rising to the peak, and water is replaced optionally; (2) acid
pickling,
rust removal and scale removal treatment:
pollution discharge and water replenishing are
shut down under the condition that the water quantity of the
system is guaranteed, acid and a
corrosion and scale inhibition agent are added to control the pH to range from 5.5 to 6.5, when the concentration of iron ions tends to balance basically, acid
pickling can be completed, and then water is replaced; (3) pre-filming treatment: pre-filming treatment is started after the
turbidity of circulating water is lower than 10 NTU and rho (Fe<3+>) is lower than 1.0 mg / L. With the
chemical cleaning and pre-filming method,
eutrophication of surrounding water can be avoided when discharging after pre-filming is ended.