天然褐铁矿添加剂对无烟煤燃烧及NOx排放的影响  

Effect of limonite additive on combustion and NOx emission characteristics of anthracite

作　　者：杨利超 罗慧娟 张凯[1] 龚志军[1] 武文斐[1,2] YANG Lichao;LUO Huijuan;ZHANG Kai;GONG Zhijun;WU Wenfei(Key Laboratory of Integrated Exploitation of Bayanobo Multi-metal Resources,Baotou 014010,China;Inner Mongolia Autonomous Region Key Laboratory of Efficient Clean Combustion,Baotou 014010,China)

机构地区：[1]内蒙古科技大学能源与环境学院,内蒙古包头014010 [2]内蒙古自治区高效洁净燃烧重点试验室,内蒙古包头014010

出　　处：《煤炭学报》2019年第S01期305-312,共8页Journal of China Coal Society

基　　金：内蒙古自然科学基金资助项目(2018LH05013);内蒙古科技局资助项目(2017Z1009-3)。

摘　　要：采用煤粉添加剂技术改善煤粉燃烧效率和NO x排放是煤炭节能减排领域的研究热点。本文选用天然褐铁矿为添加剂,探究不同添加量褐铁矿对无烟煤燃烧行为及NO x排放的影响。试验分为3部分,采用热重分析(TG)褐铁矿对无烟煤燃烧行为的影响,选取200~300目的褐铁矿及无烟煤,取无烟煤与不同添加量(2%,5%,10%,20%)褐铁矿研磨充分后,放入样品坩埚,热重从室温升至900℃,分析TG-DTG曲线,计算燃烧参数;采用固定床脱硝实验台,采用N 2/O 2(4∶1)气氛,反应温度为800℃,称量无烟煤与不同比例的褐铁矿混合,通过烟气分析仪得出NO x的瞬时浓度,继而得到NO x的排放总量,最后计算脱硝率,观察添加褐铁矿对无烟煤脱硝性能的影响;采用SEM,XRD,XPS对燃烧前后的样品进行理论分析,探究催化原理。结果表明,在添加量为10%时,无烟煤的着火温度降低18℃,燃尽温度降低24℃,放热量增加13.4%,无烟煤NO x排放量降低48.07%;SEM,XRD和XPS综合表征发现,Fe元素的氧化-还原循环促进了煤粉的燃烧和NO x的还原,从而起到同时催化燃烧脱硝的作用;在煤粉燃烧过程中褐铁矿能有效催化无烟煤的燃烧和脱硝性能。本研究将为天然矿物褐铁矿在高效洁净燃烧领域的应用提供参考。The use of pulverized coal additive technology to improve pulverized coal combustion efficiency and NO x emissions is a research hotspot in the field of coal energy conservation and emission reduction.In this paper,natural limonite was used as an additive to investigate the effects of different amounts of limonite on the combustion behavior and NO x emissions of anthracite.The test was divided into three parts.The first part used the ther-mogravimetric(TG)to analyze the influence of limonite on the burning behavior of anthracite.The 200-300 mesh limonite and anthracite were selected,and 20 mg anthracite and different addition amount(2%,5%,10%,20%)were weighed.After the limonite was fully ground,10 mg was placed in the sample crucible,the thermogra-vimetry was raised from room temperature to 900℃,and the TG-DTG curve was analyzed to calculate the com-bustion parameters.The second part used the fixed bed denitration test bench,adopted N 2/O 2(4∶1)atmosphere,the reaction temperature was 800℃,weighed 100 mg anthracite and mixed with different proportions of limonite,and obtained the instantaneous NO x through the flue gas analyzer,then the total amount of NO x emissions,and finally calculated the denitration rate,observed the effect of adding limonite on the denitrification performance of anthracite.The third part used SEM,XRD and XPS to analyze the samples before and after combustion to explore the catalytic principle.The results show that when the addition amount was 10%,the ignition temperature of an-thracite was lowered by 18℃,the burnout temperature was lowered by 24℃,and the heat release was increased by 13.4%.Anthracite NO x emissions decreased by 48.07%.The comprehensive characterization of SEM,XRD and XPS found that the oxidation-reduction cycle of Fe promoted the combustion of pulverized coal and the reduction of NO x,thus simultaneously catalyzed the denitration of combustion.Limonite can effectively catalyze the combustion and denitrification performance of anthracite during pulverized coal comb

关 键 词：褐铁矿 无烟煤 燃烧行为 氮氧化物 催化 

分 类 号：X511[环境科学与工程—环境工程]