循环流化床超低NO_(x)与SO_(2)排放技术研究进展  

Research progress on ultra-low NO_(x) and SO_(2) emissioncontrol technology for CFB boilers

作　　者：王超 宋国良[1,3,4] 吕清刚[1,3,4] WANG Chao;SONG Guoliang;LYU Qinggang(Institute of Engineering Thermophysics,Chinese Academy of Science,Beijing 100190,China;University of Science&Technology of China,Hefei 230026,China;University of Chinese Academy of Science,Beijing 100049,China;Dalian National Laboratory for Clean Energy,Chinese Academy of Science,Dalian 116023,China)

机构地区：[1]中国科学院工程热物理研究所,北京100190 [2]中国科学技术大学,安徽合肥230026 [3]中国科学院大学,北京100049 [4]中国科学院洁净能源创新研究院,辽宁大连116023

出　　处：《洁净煤技术》2021年第4期17-25,共9页Clean Coal Technology

基　　金：国家重点研发计划资助项目(2018YFB0605002);中国科学院战略性先导科技专项资助项目(XDA21040100)。

摘　　要：因固有的低污染物排放控制成本优势,循环流化床(CFB)锅炉已成为商业化程度最好的洁净煤燃烧技术之一。随着超低排放标准的提出,CFB燃烧技术也面临巨大挑战。为满足超低排放标准,通常要使用烟气净化处理装置,导致CFB锅炉污染控制成本显著增加。如何低成本实现CFB锅炉NO_(x)与SO_(2)原始超低排放成为关注焦点。系统论述了现有CFB超低NO_(x)和SO_(2)排放技术、最新开发的CFB超低NO_(x)燃烧技术、炉内CFB超低SO_(2)排放技术和CFB超低NO_(x)、SO_(2)协同控制技术等。研究表明:开发高效分离器不仅可提升CFB燃烧效率,也是保证超细石灰石高效脱硫的前提,分离器效率越高,CFB燃烧效率和超细石灰石脱硫效率越高;随着循环流化床锅炉的大型化发展,炉膛截面越来越大,如何实现超细石灰石在大型炉膛内横向的均匀混合成为第1个技术难点;控制单一气体使其满足超低排放的技术相对成熟,但如何协同控制NO_(x)和SO_(2)使之满足超低排放标准成为第2个技术难点;现阶段CFB炉内超低排放技术仅针对某些特定的燃料可达到超低排放,针对其他常规燃料,NO_(x)和SO_(2)能否达到超低排放仍需要进一步深入研究。Circulating fluidized bed(CFB)boilers have become one of the best commercial technologies of clean coal combustion due to the advantage of inherent low cost of controlling pollutant emission.With the introduction of ultra-low emission standards,CFB combustion technology also faces huge challenges.In order to meet the ultra-low emission standards,the devices for treatment of flue gas are usually used,resulting in a significant increase in the cost of pollution treatment for CFB boiler.How to achieve ultra-low NO_(x) and SO_(2) emissions of CFB boiler has become the research focus.The existing conventional ultra-low NO_(x) emission technology of CFB,ultra-low SO_(2) emission technology of CFB,newly developed ultra-low NO_(x) combustion technology of CFB,ultra-low SO_(2) emission technology in the furnace of CFB and ultra-low NO_(x) and SO_(2) cooperative control technology of CFB were systematically discussed.The results show that high-efficiency separators cannot only improve the combustion efficiency of CFB,but also is the premise of using ultra-fine limestone for highly efficient desulfurization.The higher the separator efficiency is,the higher the CFB combustion efficiency and ultra-fine limestone desulfurization efficiency is.With the large-scale development of circulating fluidized bed boilers,the cross-section of the furnace is getting larger and larger,so how to achieve the horizontal uniform mixing of ultra-fine limestone in the large furnace becomes the first technical challenge.The technology for controlling a single gas to meet the ultra-low emission is relatively mature,but how to coordinately control NO_(x) and SO_(2) to meet the ultra-low emission standard has become the second technical challenge.The current ultra-low emission technology in the furnace of CFB can only achieve ultra-low emissions for certain specific fuels,and however for other conventional fuels,whether NO_(x) and SO_(2) can achieve ultra-low emissions still needs further deep research.

关 键 词：CFB 超低NO_(x)排放 超低SO_(2)排放 超细石灰石 协同控制 

分 类 号：TK229[动力工程及工程热物理—动力机械及工程] X511[环境科学与工程—环境工程]