Design Considerations in Seawater Corrosion Protecting System

2 Design Considerations in Seawater Corrosion Protecting System 

Seawater as mentioned earlier is mostly the process cooling fluid for coastal based power plants. The main design considerations for selection of corrosion protection measures for seawater-based process cooling systems are  

Much effort has been put into finding the proper material for seawater applications. Some of the materials for seawater applications are concrete with or without protective lining, carbon steel with protective lining, stainless steel, titanium, inconel and aluminium alloys. 

Stainless steel 316L material used for piping and equipment shows considerable corrosion resistance because of the beneficial effect of molybdenum on the surface properties. It is also observed that the surface treatment (pre-reduced, polished, passivated and chemically treated surfaces) of stainless steel equipment and piping reduces the corrosion process in seawater applications. The corrosion resistance of stainless steel in seawater applications can also be enhanced by bulk alloying the stainless steel with nitrogen, chromium, molybdenum and nickel by converting the stainless steel into super austenitic stainless steel. From leaching studies it is also observed that the release of iron, chromium and nickel from the super austenitic stainless steel to seawater is considerably 

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