气化滤饼中碳赋存形态及循环掺烧可行性研究  

Investigation on the occurrence of carbon in gasification filter cake and its feasibility of circulating combustion

作　　者：李金凤 LI Jinfeng(China Shenhua(Baotou)Charcoal Chemical Industry Co.,Ltd.,Baotou 014060,China)

机构地区：[1]神华包头煤化工有限责任公司,内蒙古包头014060

出　　处：《洁净煤技术》2020年第6期224-228,共5页Clean Coal Technology

基　　金：神华包头煤化工有限责任公司工业固体废物物联网企业端建设项目(JG-20-15)。

摘　　要：煤气化技术作为煤炭高效清洁转化利用的重要技术,其无机组分约占20%,主要以气化灰渣(气化滤饼和粗渣)形式外排,其中气化滤饼碳含量达20%~50%,是资源化利用的关键技术瓶颈,由于缺乏对碳微观物化性质的深入分析,导致脱碳效率低、成本高,主要以堆存方式处理,造成环境污染。针对上述问题,以内蒙古某公司气流床气化得到的气化滤饼为研究对象,采用XRD谱图精修、粒度仪、扫描电镜、碳硫分析仪、热重分析仪以及灰熔点分析仪等对气化灰渣的元素/矿相组成、碳结晶度、碳在不同粒度中的分布规律、碳与无机相赋存形态和微观形貌、碳失重范围以及气化滤饼的反应活性等方面进行研究。结果表明:气化滤饼中碳主要以反应活性较高的无定型碳和惰性的石墨碳2种形态存在,其比例分别为92.94%和7.06%,其赋存形态主要是由煤种和气化条件决定;气化滤饼中碳赋存形态包括单独存在的絮状碳颗粒、与无机组分熔融的不规则颗粒,且细颗粒中含碳量高,粗颗粒中无机组分含量高;500~700℃热重分析的失重高达27.38%,与碳硫分析和马弗炉烧失量结果较为一致,说明该部分烧失部分主要是碳的高温热解导致;通过分析灰熔融温度,发现软化温度在1130℃,流动温度在1247℃,在煤气化温度范围内具有较高的反应活性,可用于循环掺烧实现碳资源的高效回收利用。Coal gasification technology is an important technology for the efficient and clean conversion and utilization of coal.Its inorganic components account for about 20%,which is mainly discharged in the form of gasification ash and slag(gasification filter cake and coarse slag),and especially the content ofcarbon in gasification filter cake is about 20-50%,which is the key technical bottleneck of resource utilization.Due to the lack of in-depth analysis of the microscopic physical and chemical properties of carbon in gasification ash and slag,the carbon removal efficiency is low and the cost is high,and the resource utilization is difficult.At present,it is mainly handled by stacking,resulting in serious environmental pollution.In the view of the above problems,the gasification filter cake obtained from entrained flow gasification of a company in Inner Mongolia was taken as the research object in this study.XRD spectrum refinement,particle size analyzer,scanning electron microscope,carbon and sulfur analyzer,thermogravimetric analyzer,ash melting point analyzer and other methods were adopted to study and analyze the elements/minerals phase composition,carbon crystallinity,the distribution of carbon in different particle sizes,the morphology and microstructure of carbon and inorganic phase,the weight loss range of carbon,and the reactivity of gasification filter cake.The results show that the carbon in the gasification filter cake is mainly composed of amorphous carbon with high reactivity and inert graphite carbon with the proportions of 92.94%and 7.06%respectively,which is mainly determined by the type of coal and gasification conditions.The morphology of carbon in the gasification filter cake includes flocculent carbon particles which exist alone and irregular carbon particles fused with inorganic components.The fine particles have a high carbon content and the coarse particles have a high inorganic component content.Under the condition of 500-700℃,a weight loss bythermogravimetric analysis is up to 27.38%,which

关 键 词：煤气化 气化滤饼 碳 基础物性 反应活性 高效脱碳 

分 类 号：TQ54[化学工程—煤化学工程] X7[环境科学与工程—环境工程]