We often receive the following question about the materials of construction of condensate polisher vessels.
We're considering a condensate polisher in our boiler plant. Should the vessel be constructed of carbon steel or stainless steel?
Over 75% of the condensate polishers that Res-Kem builds utilize stainless steel pressure vessels. If you use a carbon steel vessel it will have to be provided with a high temperature liner for corrosion resistance. For a condensate polisher with a diameter of 30" or less, the liner can not be installed working from inside the tank and the quality of the lining is unpredictable. In fact most liner companies will not warrant their linings if the vessel diameter is less than 36".
Stainless steel vessels cost a little more however the entire lining issue goes away as one is not required. For condensate polishers 30" or less in diameter it does not make sense to even consider a carbon steel vessel with a liner.
Res-Kem builds a very economical line of standard stainless steel condensate polishers from 20 inch to 66 inch diameter vessels . Our standard designs employ stainless steel vessels, flanged and welded stainless steel face piping. Depending upon the size of the valves we use stainless steel Aquamatic diaphragm and/or butterfly valves. To save a little money, we have an option for smaller size systems using stainless steel vessels, threaded steel face piping, and cast iron Aquamatic diaphragm valves.