摘要
煤气化过程中产生大量含碳量较高的气化细渣,目前主要以填埋方式处理,不仅占用大量土地,污染土壤和水体,同时造成能源浪费,对气化细渣进行高效环保的资源化利用是目前的研究热点。气化细渣中的残碳与灰组分分离是实现其高值化、减量化、无害化利用的关键,煤气化细渣粒度特性分析表明,各粒级产品灰分基本随粒级减小呈增大趋势,通过分级工艺可实现碳灰的分离与富集。榆林煤气化细渣固定碳含量随粒级减小均呈下降趋势,各粒级产品中均含有较多的SiO_(2)、Al_(2)O_(3)、Fe_(2)O_(3)、CaO,微观形貌主要由多孔基体、不规则颗粒、黏附小颗粒及圆球颗粒组成。煤气化细渣孔隙结构发达,比表面积丰富,>75μm粒级产品可直接作为优质的吸附材料;与气化燃料煤相比,气化细渣各粒级产品燃烧的特征温度均显著提高,从着火温度看,除<45 um颗粒外,着火特征温度都高于作为参照的无烟煤;由于气化细渣中丰富孔隙率的存在,增大了颗粒与氧气的接触面积,使燃烧中后阶段燃烧峰值温度低于无烟煤,且燃尽温度明显低于无烟煤。
A large amount of gasification fine slag with high carbon content is produced in the process of coal gasification.At present,it is mainly treated by landfill,which not only occupies a lot of land,pollutes soil and water,but also causes energy waste.How to efficiently and environmentally utilize gasification fine slag as a resource is the hot spot of current research.The separation of residual carbon and ash in gasification fine slag is the key to realize its high value,reduction and harmless utilization.The analysis of particle size characteristics of gasification fine slag shows that the ash content of each particle size increases with the decrease of particle size,and the separation and enrichment of carbon and ash can be realized by screening and classification process.The results show that the fixed carbon content of Yulin coal gasification fine slag decreases with the decrease of particle size.There are more SiO_(2),Al_(2)O_(3),Fe_(2)O_(3) and CaO in each particle size.The micro morphology is mainly composed of porous matrix,irregular small particles,flocculent particles and spherical particles.The results show that the pore structure of coal gasification fine slag is developed,the specific surface area is rich,and the products with particle size>75μm can be directly used as high-quality adsorption materials.Compared with the gasification fuel coal,the combustion characteristic temperature of each particle size of coal gasification fine slag is significantly increased,and the ignition characteristic temperature is higher than that of anthracite except for<45μm particles.Due to the existence of rich porosity in gasification slag,the contact area between particles and oxygen is increased,so that the peak combustion temperature of combustion is lower than that of anthracite and the burnout temperature is significantly lower than that of anthracite in middle and later stage of combustion.
作者
王学斌
于伟
张韬
白永辉
刘莉君
史兆臣
殷瑞
谭厚章
WANG Xuebin;YU Wei;ZHANG Tao;BAI Yonghui;LIU Lijun;SHI Zhaochen;YIN Rui;TAN Houzhang(School of Energy and Power Engineering,Xi'an Jiaotong University,Xi'an 710049,China;School of Chemistry and Chemical Engineering,Xi'an University of Science and Technology,Xi'an 710054,China;Yantai Longyuan Power Technology Co.,Ltd.,Yantai 264006,China;State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering,College of Chemistry and Chemical Engineering,Ningxia University,Yinchuan 750021,China;Beijing ENSA Engineering Co.,Ltd.,Beijing 100101,China)
出处
《洁净煤技术》
CAS
北大核心
2021年第3期61-69,共9页
Clean Coal Technology
基金
国家重点研发计划资助项目(2020YFC1910000)
省部共建煤炭高效利用与绿色化工国家重点实验室开放课题资助项目(2019-KF-12)。
关键词
煤气化细渣
粒度特性
微观形貌
孔隙结构
燃烧
coal gasification fine slag
particle size characteristics
micro morphology
pore structure
combustion
作者简介
王学斌(1984—),男,山东昌邑人,教授,博士生导师,从事燃烧和污染物控制方面研究。E-mail:wxb005@mail.xjtu.edu.cn。
