Thermofor Catalytic Cracking Gas Plant Corrosion Survey^⋆ Available to Purchase

Severe corrosion has been experienced in a Thermofor catalytic cracking gas plant over several years. Representative inspection findings are outlined. A complete chemical survey of gas plant streams for amount and type of corrosives, together with water present, is given. Ammonia and hydrogen sulfide are indicated the principal corrosives present. These have caused corrosion of overhead condensing equipment. Some ammonia acid salts are present which have dissociated at reboiler temperatures to give acid conditions which have caused rapid attack of reboiler tubes. Measures are suggested to remove water, which will also remove the principal corrosive constituents at appropriate points in the system. Possible places for chemical injection are suggested to neutralize any traces of remaining corrosives.