We have gained a thorough understanding of the anti-corrosion principles for heat exchangers. Implementing reasonable anti-corrosion measures ensures optimal equipment performance and efficiency. The heat exchanger manufacturer has proposed the following three anti-corrosion methods:
1. Electrochemical Corrosion Protection
Electrochemical selection of protective methods for anodes and cathodes. Anode protection involves using direct current to convert the metal surface into a positive pole for protection. However, this method consumes a significant amount of electricity, resulting in high costs. Cathode protection connects the heat exchanger to the negative pole of an external power source, causing a passivation film to form on the metal surface, thereby achieving protection.
2. Corrosion-resistant materials
Chosen for their corrosion-resistant properties (such as duplex stainless steel, Hastelloy, titanium, titanium alloys, copper, and more advanced fluoroplastic materials), these materials can effectively extend the lifespan of heat exchangers. However, due to their high corrosion resistance, they are more expensive than standard materials, resulting in higher manufacturing costs and a significant upfront investment, which often hinders their promotion. Under the national strategy of reducing overcapacity and upgrading equipment, long-term development is being considered. According to the 2015 data from the Chemical Society, heat exchangers using corrosion-resistant fluoroplastic materials account for 65% of the market. 2. Corrosion-resistant Coating Method: On metal surfaces, a protective layer of corrosion-resistant coating is applied through specific coating techniques to prevent direct contact between the metal surface and corrosive media. This method is both economical and effective, originally used to prevent gas medium corrosion, with most coatings being organic polymer solutions. Now, there is a trend towards developing oil and solvent-resistant coatings, high-temperature coatings, heavy-duty corrosion-resistant coatings, and coatings for special environments.
3. Enhanced Corrosion Inhibitor Method
In corrosive mediums, certain substances can be introduced in small quantities, which significantly reduce or even eliminate metal corrosion. These substances are known as corrosion inhibitors. The addition of corrosion inhibitors should be guided by the principle of not affecting production processes and product quality.
