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焦煤的热解经历干燥阶段、胶质体阶段和焦炭生成三个阶段,第二阶段焦煤失重较多。常压条件下焦煤热解时固定炭损失较多,孔隙度随温度和时间的增加而增加,500℃热解30 min后胶质体数量较少,物料内部变化不大;真空条件下煤热解时固定炭不损失,孔隙度随温度的升高而降低,且随着时间的延长升高,60 min后降低,500℃热解30 min可生成较多数量的胶质体,碳元素和镁元素分布趋于均匀。用焦煤做还原剂进行氧化镁真空碳热还原可以得到较纯净的金属镁,没有发生喷料现象。焦煤具有良好的黏结性和结焦性,适于做还原剂。
Coking coal pyrolysis experienced drying stage, colloidal phase and coke formation of three stages, the second phase of coking coal more weight loss. Atmospheric pressure of coking coal pyrolysis fixed more carbon loss, porosity increases with temperature and time, pyrolysis at 500 ℃ 30 min after the number of less colloidal material within the little change; under vacuum heat When fixed, the charcoal will not be lost and the porosity will decrease with increasing temperature. The porosity will increase with time, decrease after 60 min and pyrolyzed at 500 ℃ for 30 min to produce more colloid, carbon and Magnesium distribution tends to be uniform. Using coking coal as a reductant for magnesium oxide vacuum carbothermal reduction can be more pure magnesium metal, there is no spray phenomenon. Coking coal has good cohesion and coking, suitable for reducing agent.