Nöytralisering av pulverformig avfall fra elektronikkskrot ved produksjon av glassifisert slagg i plasmaovn, samt gjennvinning av verdifulle elementer

摘要

PCT No. PCT/NO94/00068 Sec. 371 Date Dec. 28, 1995 Sec. 102(e) Date Dec. 28, 1995 PCT Filed Mar. 25, 1994 PCT Pub. No. WO94/23856 PCT Pub. Date Oct. 27, 1994Method for neutralizing waste, such as powder from luminescent tubes and similarly, residue from incineration of household waste, optionally comprising environmentally hazardous components, such as Hg, Cd, Zn, Co or Ba. The waste is fed into a melting furnace in conjunction with an SiO2-rich material, and a reducing agent, and in a first optional step, the furnace is operated at reducing conditions and at a temperature effecting reduction of heavy metals and any other compounds in the raw material, whereby the reduced heavy metal and other components are withdrawn from the furnace with the exhaust gas and are separated from the same, and in a second step the furnace is operated at oxidizing conditions and at a temperature ensuring oxidation of remaining elements in the slag present in the furnace from said first step, whereby the slag becomes, at least gradually, of low viscosity, and the molten slag is drained from the furnace and solidified, optionally die casted and/or water granulated, thus forming inert glassified slag.