煤热解半焦特性及其钝化工艺初步设想  

Characteristics of Semi-coke from Coal Pyrolysis and Preliminary Ideas of Its Passivating Process

作　　者：陈静升 贾培军 Chen Jingsheng Jia Peijun(Shaanxi Coal and Chemical Technology Institute Co., Ltd., Xi＇an Shaanxi 710065, China)

机构地区：[1]陕西煤业化工技术研究院有限责任公司,陕西西安710065

出　　处：《煤化工》2017年第5期25-29,共5页Coal Chemical Industry

基　　金：陕西省科技统筹创新工程计划资助项目(2013KTZB01-04-02)

摘　　要：由于热解半焦在生产、储运及应用过程中,存在自燃等安全隐患,从热解半焦的自燃机理出发,分析了热解半焦的组成特性、官能团种类、比表面积以及孔道特性对其自燃倾向性的影响,提出将热解半焦冷却、钝化和余热回收高度集成耦合的新型半焦钝化工艺,即利用N2惰性气体作为冷却介质,回收利用高温半焦携带显热;通过水蒸气与半焦活性基团反应,适当减少含氧官能团数量;通过钝化剂前驱体Ca(OH)2和CO2在半焦颗粒表面的分步反应包覆,适当减少活性焦比表面积;通过适当增加半焦含水量,有效防止半焦存放时水分复吸,从而实现半焦钝化和余热回收的双重目的。Semi-coke has the characteristics of high chemical activity,rich porosity and large specific surface area.Therefore,there are some hidden dangers in spontaneous combustion during production,storage and transportation. Based on the spontaneous combustion mechanism of semi-coke,the effects of the composition,types of functional groups,specific surface area and pore structure of semi-coke on its spontaneous combustion tendency were analyzed. A new semi-coke passivation technology was proposed in the paper through high integration and coupling of pyrolyzed semi-coke cooling,passivation and waste heat recovery. The technology utilized N2 inert gas as the cooling medium to recycle and utilize the sensible heat of hot semi-coke,appropriately reduced the amount of oxygen containing functional groups through the reaction between water vapor and active functional groups,appropriately reduced the specific surface area of semi-coke through the step reaction of passivator precursor calcium hydroxide and carbon dioxide on the surface of the semi-coke particles,and effectively prevented the moisture absorption during the semi-coke storage through appropriately increasing the water content of semi-coke,so as to realize semi-coke passivation and waste heat recovery.

关 键 词：煤热解 半焦 自燃机理 钝化 节能减排 余热回收 

分 类 号：TQ530.2[化学工程—煤化学工程]