Corrosion prevention electrolyzer

All electrodes are suspended from a cement or asbestos-cement cover, which closes tightly the tank. Generally, a coil is fixed in the middle of the tank, through which cooling water passes in order to maintain the desired temperature. The coil is conductively connected with the cathodes to prevent corrosion. Hydrogen evolved at the cathode passes through a pipe at the cover. Hydrochloric acid is continuously introduced into the electrolyte by another pipe in the cover, in quantities sufficient to maintain the acidity of the solution at 0.016 N-HC1. The electrolyzers are equipped with convenient overflows, through which the electrolyte flows to the tank l>elow. Each tank holds about 5.5 cu. m of electrolyte, which is maintained at 70 °C. 

Hydrogen bubbles as they form, move the brine solution to be electrolyzed through the chlorate cell and up to the chemical chlorate reactor without any moving parts. Chlorate cells are operated with sodium dichromate inhibitor present in the brine to prevent corrosion from hypochlorite ion. 

Leakage currents can be short circuited [64] or biased by placing an opposite current via electrodes placed in the piping [40] or reacted at sacrificial electrodes located in the manifolds [65]. These concepts have been used in the manifolds of MBC electrolyzers of Chlorine Engineers and also in the design of the CME and BiTac cells. Corrosion of catalytic cathodes used in bipolar water electrolyzers during shutdowns is prevented by cathodic protection [9]. 

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