Corrosion hazards to cooling towers

Salt spray, chemical acidic gas or high chloride ion water in coastal areas will accelerate equipment corrosion, resulting in coil perforation and reduced structural strength. Anti-corrosion closed cooling towers extend their service life to more than 15 years through material upgrades and process improvements.

Key anti-corrosion technology

Super austenitic stainless steel: 254SMO, AL-6XN and other materials are selected, with pitting resistance equivalent (PREN) >40.

Coating protection system: The inner wall of the spray system is coated with epoxy resin + polyurethane double-layer coating, which is resistant to pH 2~12 corrosion.

Cathode protection: Sacrificial anodes (such as magnesium alloys) or impressed current protection are applied to carbon steel parts.

Structural sealing design: All-welded coils avoid crevice corrosion at flange connections.

Selection Guide and Cost Analysis

Material Comparison:

316L stainless steel: suitable for general corrosive environments (Cl⁻<1000ppm).

Titanium tube: the first choice for seawater cooling scenarios, but the cost is three times that of stainless steel.

Composite materials: FRP shell with graphite-modified polypropylene coil, outstanding cost performance.

Life Cycle Cost (LCC): The initial investment of the anti-corrosion type is high, but the maintenance cost is reduced by 60%.

Industry Application Practice

Desalination plant: Titanium tube closed cooling tower withstands high-salinity seawater corrosion.

Electroplating industry: Acid-resistant coating resists erosion by chromic acid and sulfuric acid mist.

Offshore platform: Heavy-duty anti-corrosion coating system certified by ISO 12944 C5-M.

Maintenance and repair technology

Regular inspection: Measure the wall thickness of the coil every quarter, and use an eddy current flaw detector to detect microscopic defects.

Coating repair: Use cold welding technology to repair local damage to avoid large-scale replacement.

Chemical cleaning: Citric acid circulation cleaning removes scale and extends the life of the coil.

Frontier anti-corrosion research

The plasma spraying (APS) process generates an Al2O3-TiO2 composite ceramic layer on the surface of the titanium alloy, with a hardness of HV1200 and a corrosion resistance of more than 5 times. If you want to know about anti-corrosion closed towers, you can find Qidu Cooling Tower Manager Wang (+86) 139-2575-3875