PURPOSE:To recover caustic soda etc., without using surplus energy by utilizing power generated from incinerator off-gas, melting burnt dust and carrying out electrolysis of slug mainly constituted of water soluble salts generated therein. CONSTITUTION:Burnt dust is separated after feeding high temperature off-gas from an incinerator into a boiler for recovering heat energy. Said separated burnt dust is melted by a direct electric melting oven 1 provided with two stage slag discharge outlets 6 and 7, upper and lower. The slag mainly constituted of water soluble alkali metallic salt coming out from said upper discharge outlet 6 is mixed with water and then electrolyzed. Further, power is generated by using the heat energy of said off-gas and the power generated therein is utilized as a power source for said melting treatment and electrolysis. As a result, caustic soda, chlorine or hypochlorous acid soda can be recovered without using surplus energy.
展开▼
