煤炭燃烧过程中大气污染物NOX形成与转化研究进展  

Progresses of research on the formation and transformation of NOX as atmospheric pollutant during coal burning

作　　者：郭思聪 张凯霞 刘守军[2] 杨颂[2] 杜文广[1] 张红霞 上官炬[1] 支国瑞[4] GUO Si-cong;ZHANG Kai-xia;LIU Shou-jun;YANG Song;DU Wen-guang;ZHANG Hong-xia;SHANGGUAN Ju;ZHI Guo-rui(Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province,Taiyuan University of Technology,Taiyuan 030024,China;College of Chemistry and Chemical Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Periodical Center,Taiyuan University of Technology,Taiyuan 030024,China;Chinese Research Academy of Environmental Sciences,Beijing 100012,China)

机构地区：[1]太原理工大学煤科学与技术教育部和山西省重点实验室,山西太原030024 [2]太原理工大学化学化工学院,山西太原030024 [3]太原理工大学期刊中心,山西太原030024 [4]中国环境科学研究院,北京100012

出　　处：《应用化工》2020年第12期3205-3212,3245,共9页Applied Chemical Industry

基　　金：国家自然科学基金项目(21878210);大气重污染成因与治理攻关项目(DQGG-0511);山西转型综改示范区自主创新项目(2016CXJJ021);煤科学与技术省部共建国家重点实验室培育基地开放基金(mkx201805)。

摘　　要：煤炭燃烧释放的烟气中氮氧化物(NOX)是大气形成酸雨、光化学烟雾、雾霾的重要污染物,目前控制燃煤NOX释放的常规方法是燃烧后烟气脱硝。鉴于大型燃煤锅炉烟气脱硝方法还存在脱硝效率低、运行成本高、氨逃逸、颗粒物产生(生成白色烟气),以及城镇、城乡结合部、农村居民燃煤以及小型工商业、设施农业散煤燃烧无组织排放、未设置脱硝设施等不足,研发燃煤过程中NOX控制(燃煤过程中原位还原脱硝)对实现燃煤烟气直排NOX浓度达标排放或间接降低NOX浓度来减轻后续烟气脱硝负荷具有重要科学和应用价值。从燃煤过程中细分的低温热解和高温燃烧两个连续阶段产生的氮化物形态,NOX的形成与转化及影响因素,过渡金属、碱土金属、碱金属等化合物对燃煤过程中原位还原脱硝的催化作用等方面,全面综述了煤炭燃烧过程中NOX形成与转化规律,指出煤燃烧过程中通过热解降低NOX前驱物含量耦合燃烧原位还原NOX成N2两个途径来控制燃煤NOX释放,并强调通过引入添加剂促进NOX催化还原成N2来达到降低燃煤NOX释放的思路,为煤炭燃烧过程中原位热解减少NOX前驱物和燃烧脱硝的两步协同催化作用的科学研究及技术开发,最终降低燃煤NOX释放提供理论和技术依据。Nitrogen oxides(NOX)in the flue gas released by coal combustion are important pollutants for the formation of acid rain,photochemical smog and haze in the atmosphere.The flue gas denitrification after combustion is the current conventional method for controlling the release of NOX from coal combustion.However,there are still massive drawbacks such as low denitrification efficiency,high operating cost,ammonia escape and particulate matter production(generate white flue gas)in the large coal-fired boiler flue gas denitrification method.And the flue gas from coal burning is discharged into the atmosphere without organization or denitrification facilities in towns,urban,rural areas,small industry and commerce,and controlled environmental agriculture.The research of how NOX control in the process of coal burning(reduction and denitrification in situ during coal combustion)achieves the standard discharge of NOX concentration from coal flue gas or indirectly reducing the concentration of NOX to reduce the subsequent denitrification load of flue gas,therefore,plays an important role in the field of not only technology but application.The coal combustion is divided into two steps i.e.coal pyrolysis at low temperature and coal combustion at high temperature.In addition,the formation and transformation of NOX in coal burning process were comprehensively discussed from three aspects,that is,the nitrogen form,the formation and transformation of NOX and its influencing factors,and the catalytic effect of metal compounds such as transition metal,alkali earth metal and alkali metal on NOX in situ reduction and denitrification.It is pointed out that NOX release can be controlled by reducing the content of NOX precursor through pyrolysis and reducing NOX to N2 in situ during coal combustion.It is emphasized that the idea of reducing NOX release from coal by introducing additives is to promote catalytic reduction of NOX to N2,which provided theoretical and technical basis for the study of reducing NOX release from coal by two-step

关 键 词：煤炭 热解 燃烧 脱硝 催化作用 

分 类 号：TQ534.9[化学工程—煤化学工程] TQ536.1