Abstract: In order to solve the high added value utilization problem of liquid drain slag，residual carbon particles and vitreous material of coarse slag from coal water slurry gasification furnace were separated by water washing. Their compositions and structures were determined using elemental analyzer，calorimeter，inductively coupled plasma emission spectrometer and X-ray diffracmeter. The extraction methods of SiO2 and the influence of particle size，reaction liquid concentration，reaction liquid-solid ratio，reaction temperature and reaction time on the extraction rate of Fe and SiO2 in vitreous material by leaching with hydrochloric acid and sodium hydroxide solution separately were studied. Elemental analysis showed that C accounted for more than 63% in residual carbon. The net calorific value of residual carbon exceeded 21MJ/kg on dry basis. Vtreous material with 93.47% of Si，Al，Ca and Fe oxides was amorphous and was easy to react with acid. By this way，more than 90% of Fe and 93% of SiO2 were extracted from vitreous material and almost 92% of solid waste discharge were reduced.

Key words: coal slag, leaching, liquid drain slag, recovery, solid waste

摘要： 针对液态排渣方法排出的煤渣长期得不到有效利用的现状，以水煤浆气化炉锁斗排出的煤渣为研究对象，通过水介质洗选将其分离为未燃炭粒和硅酸盐玻璃渣体，分别采用元素分析仪、量热仪、电感耦合等离子发射光谱仪和X射线衍射仪对上述固体进行分析，考察了SiO2提取方法及颗粒粒径、浸取液浓度、反应液固比、反应温度和反应时间等实验条件对硅酸盐玻璃渣体中Fe、SiO2浸取率的影响。结果表明，所得炭粒中C元素含量大于63%，干基低位发热量超过21MJ/kg。硅酸盐玻璃渣体晶相结构为无定形，Si、Al、Ca和Fe氧化物含量之和占到总量的93.47%，加入酸可破坏原料的化学结构。用盐酸和氢氧化钠溶液浸取硅酸盐玻璃渣体，可浸出90%以上的Fe和93%以上的SiO2，固体废弃物减排近92%。

关键词: 煤渣, 浸取, 液态排渣, 回收, 固体废弃物