Reducing emission of sulphur cpds in waste gases - esp from incinerators for black liquor in cellulose industry

摘要

In a process for reducing the emission of gaseous S-cpds. from a furnace in which the cpds. are subjected to an incineration process, the supply of oxygen to the combustion process is so controlled that the cpds. are oxidised to SO2 and SO3 or H2SO4, whilst a metal carbonate is injected into the flue gases to react with the SO3 or H2SO4 to form solid metal sulphate which is sepd. from the waste gas as a solid. The technique overcomes the problems caused by the difficulty of accurate controlling the supply of air, i.e. corrosion by strongly acid as when too much air is supplied, and emission of odorous S-cpds. when too little air is supplied.