煤粉气化低氮灵活燃烧研究进展

Research and development on coal gasification-combustion technology

20世纪80年代,全俄热工研究院提出煤粉气化低氮灵活燃烧技术,该技术通过增加独立气化区域解耦了传统燃烧过程中挥发分析出阶段、燃烧阶段和燃烬阶段,使挥发分析出和焦炭燃烧成为2个独立的过程,并通过调控热解挥发分与焦炭的燃烧反应,在实现高效燃烧的同时有效地抑制了氮氧化物(NOx)的生成。综合总结了该技术近40年在煤燃烧领域的基础研究、技术开发和工程示范等方面取得的主要进展,包括该技术的降氮和稳燃原理;并以气化场所不同对煤粉气化低氮工艺进行了分类,着重介绍了流化床气化式和燃烧器气化式的工艺流程及取得的重要成果,同时对最新报道的气流床气化式燃烧工艺进行了介绍;对该技术在碳达峰碳中和背景下应用于大型燃煤电厂实现锅炉(低于20%锅炉负荷)深度调峰进行了工艺路线分析和前景展望,确定了不同煤粉气化低氮燃烧工艺在电站锅炉灵活性改造方面的技术优势、范围以及应注意的问题,以期对煤粉气化低氮灵活燃烧技术在电站锅炉领域的进一步发展提供有益参考。

The coal gasification-combustion technology decouples the volatilization stage,combustion stage and burnout stage in the traditional combustion process,making volatilization stage and char combustion two independent processes.By regulating the combustion reaction between volatile and char,it effectively suppresses the generation of nitrogen oxides(NOx)while achieving efficient combustion.This article comprehensively summarizes the main research and development made by this technology in the past forty years,including basic research,technology development and engineering demonstration,and also introduces the latest reported entrained bed gasification method.The technology can be applied to large coal-fired power plants to achieve deep boiler peak shaving(less than 20%boiler load)under the background of"carbon neutrality"and"carbon peaking".The process route analysis and prospects are also conducted.