| 摘要 |
Thermal treatment of waste and residues is carried out by combustion, using undiluted pure O2 as oxidant. Combustion is pref. carried out so that the mineral constituents melt, pref. by keeping the temp. above the m.pt. of these. The O2 may be diluted by mixing with pt. of the waste gas or with N2, water, steam and/or CO2. Additives, pref. fly ash or slag from waste combustion and/or reaction prods. from waste gas purificn., may be used which melt at a temp. below the m.pt. of the minerals or in the same temp. range. The waste pref. is mixed with carbonaceous material (I), pref. coal, coke, pyrolysis residues, spent coke from waste gas purificn. plants, bitumen, tar, oil and/or wood, which is burnt with undiluted O2, so that the minerals melt. The waste and (I) pref. are mixed and pulverised to dust before combustion in a suitable smelter. USE/ADVANTAGE - The use of pure O2 reduces the volume of waste gas formed in the combustion of 1 t household waste from ca. 6000 cu.m to 1800 cu.m, i.e. 30% of the usual amt. Reducing the vol. increases the concn. of impurities, which facilitates sepn. and (extensive) elimination of the emission of harmful organic matter, esp, dioxins, chlorinated phenols, hexachlorobenzene, polyaromatic cpds. and incompletely burnt impurities. In an example, a mixt. of 1 kg dry residue (slag, fly ash and reaction prods. from waste gas purificn.) and 100 g mineral coal was pulverised finely and burnt in a smelter in an O2 atmos. The residue melted at 1600 deg.C, forming a glass, which set to a prod. resistant to leaching on cooling. 0.22 cu.m waste gas, mainly CO2, were formed.
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