Anodic protection of chemical plant against corrosive media - using electric circuit to maintain passive film on plant

摘要

An object in contact with an electrically conducting medium is protected against corrosion by placing a cathode in the medium, and periodically applying a polarising current, so the object forms an anode and the electric potential is kept within prescribed limits. During the intervals between the supply of the polarising current, the cathode is short-circuited to the anode. Method causes passivation of the object e.g. appts. and tanks used in the chemical-, food-, and textile- industries, and in mfg. cellulose or paper. A stable passive film is formed in the tank or other object.