Neutralising acidic condensate in heat exchanger - by contact with alkaline-reacting metal oxide

摘要

(A) Neutralisation of the acid-contg. condensate of a hot waste gas fed through the waste gas conduit of a heat exchanger is effected by contact, in the waste gas flow path, of the condensate with a metal (e.g. aluminium) oxide having an alkaline reaction with water. (B) A (pref. cast) component of the waste gas conduit of a heat exchanger, esp. a boiler component, for carrying out process (A) has its (pref. profiled) surface coated with the metal of the metal oxide. (C) Prodn. of component (B) involves coating the rough cast surface of the component, after casting, with the metal. ADVANTAGE - The metal oxide neutralises the acidic condensate to prevent corrosion.