The plate heat exchanger is a new type of high-efficiency heat exchanger stacked by a series of metal sheets with a certain corrugated shape. Thin rectangular channels are formed between various plates, and heat is exchanged through the plates.Reasonable choice of anti-corrosion measures can achieve the purpose of using equipment. The anticorrosion method of the plate heat exchanger has corrosion inhibitor and electrochemical protection.
(1) Corrosion inhibitor
Corrosion inhibitors with chromate as the main component are commonly used in cooling water systems. Chromate ion is an anode inhibitor. When it is combined with a cathode inhibitor, it can have a satisfactory and economical anticorrosive effect.Chromate-zinc-polyphosphate: The use of polyphosphate is because it has the effect of cleaning the metal surface and has the ability to inhibit corrosion. Polyphosphate can be partially converted into orthophosphate, and they can also form colloids with calcium cation.
(2) Electrochemical protection
Cathodic protection and anodic protection. Cathodic protection is the use of an external DC power supply to make the metal surface into a cathode for protection. This method consumes large power and costs a lot. Anode protection is to connect the protected heat exchanger to the anode of an external power source, so that a passivation film is formed on the metal surface to obtain protection.