水煤浆循环流化床燃烧飞灰特性研究  

Characteristics of Fly Ash from Coal Water Slurry Circulating Fluidized Bed Combustion

作　　者：张代鑫 张国庆 刘海军[4] 黄涌波 杜善周 樊保国[2] 黄中 ZHANG Daixin;ZHANG Guoqing;LIU Haijun;HUANG Yongbo;DU Shanzhou;FAN Baoguo;HUANG Zhong(College of Electrical and Power Engineering,Taiyuan University of Technology,Taiyuan,Shanxi,China;Department of Energy and Power Engineering,Tsinghua University,Beijing,China;School of Chemistry and Environmental Engineering,China University of Mining and Technology(Beijing),Beijing,China;Shenhua Zhungeer Energy Co.,Ltd.,Ordos,Inner Mongolia,China)

机构地区：[1]太原理工大学电气与动力工程学院,山西太原 [2]清华大学能源与动力工程系,北京 [3]中国矿业大学(北京)化学与环境工程学院,北京 [4]神华准格尔能源有限责任公司,内蒙古鄂尔多斯

出　　处：《太原理工大学学报》2025年第1期25-33,共9页Journal of Taiyuan University of Technology

基　　金：国家能源投资集团科技创新项目;太原市“揭榜挂帅”项目。

摘　　要：【目的】准格尔煤燃烧后灰渣中Al_(2)O_(3)含量超过45%,具有重要的资源综合利用价值。为解决传统循环流化床锅炉燃用准格尔煤时飞灰活性差、Al_(2)O_(3)提取效率低等问题,提出采用水煤浆循环流化床燃烧方式改善灰渣特性。【方法】利用3 MW循环流化床燃烧试验台研究了给料方式、运行氧量、床温、一次风率等对飞灰可燃物含量的影响,并利用比表面积及孔径测定仪、扫描电镜、X射线荧光光谱仪,X射线衍射仪等对不同粒径飞灰成分和微观形貌进行分析。【结果】结果表明:随着床温、运行氧量、一次风率的增加,飞灰可燃物含量逐渐减小;水煤浆粒化燃烧的飞灰可燃物含量明显低于未粒化。飞灰中可燃物主要存在于40μm以下颗粒,随着飞灰粒径的减小,可燃物含量逐渐增加;小颗粒飞灰大部分是由孔隙结构不发达的颗粒构成,可燃物含量较高;随着飞灰粒径的增大,飞灰比表面积和总孔容逐渐减小,平均孔径逐渐增大,粒化末煤浆的总孔容和平均孔径要小于精煤浆;对灰样进行成分分析,发现随着粒径的减小,Al_(2)O_(3)的含量逐渐增大,15μm以下粒径段飞灰中Al_(2)O_(3)的含量达到51.77%;对灰样进行物相检索和半定量分析,活性较好的γ-Al_(2)O_(3)峰随着粒径的增大逐渐减弱,莫来石含量随着粒径的增大逐渐增加,使飞灰的提铝效率降低。总体来看,粒径小于50μm的飞灰中Al_(2)O_(3)的含量更高同时莫来石含量更少,更适合作为提铝工艺原料。【Purposes】The content of Al_(2)O_(3) in the fly ash and slag after combustion of Zhungeer coal is over 45%,which has important value of comprehensive utilization of resources.In order to solve the problems of poor fly ash activity and low Al_(2)O_(3) extraction efficiency when using Zhungeer coal in conventional circulating fluidized bed boilers,a coal water slurry circulating fluidized bed combustion method was proposed to improve the ash characteristics.【Methods】The effects of feed mode,operating oxygen content,bed temperature,and primary air rate on unburned combustible in fly ash were studied by using a 3 MW circulating fluidized bed combustion test facility,the composition and micro-morphology of fly ash with different particle sizes were analyzed by using specific surface area and pore diameter analysis apparatus,scanning electron microscope,X-ray fluorescence spetrometer,and X-ray diffractometer(XRD).【Findings】The results show that the unburned combustible content in fly ash decreases with the increase of bed temperature,operating oxygen content,and primary air rate,and the unburned combustible content in fly ash in coal water slurry granulated combustion is obviously lower than that in ungranulated combustion.The combustibles in fly ash are mainly below 40μm,and the unburned combustible content increases with the decrease of fly ash particle size.Most of small fly ash particles were composed of undeveloped pore structure particles with high combustible content.The BET specific surface area and total pore volume decrease with the increase of fly ash particle size,while the average pore size increases gradually,and the total pore volume and the average pore size of the slack coal slurry are smaller than those of the clean coal slurry.It can be found that the content of Al_(2)O_(3) increases with the decrease of particle size,and the content of Al_(2)O_(3) in fly ash with particle size less than 15μm is 51.77%.Acctording to the phase retrieval and semi-quantitative analysis of ash samples,theγ

关 键 词：准格尔煤 水煤浆 循环流化床 灰渣提铝 灰渣综合利用 

分 类 号：TQ534.4[化学工程—煤化学工程]