【作者】 冯兆兴；

【导师】 安连锁； 陈鸿伟；

【作者基本信息】 华北电力大学（河北） ， 热能工程， 2007， 博士

【摘要】 煤燃烧产生的污染已成为主要的大气污染源。氮氧化物是煤燃烧产生的主要污染物之一。环境污染已经成为我国经济发展的主要制约因素之一,因此治理火电厂NO_x排放是迫在眉睫的任务。结合我国以煤电为主的国情,在目前经济发展状况下,开发有效的低NO_X燃烧技术,在未来具有非常重要的社会效益和经济效益。低NO_x燃烧技术是火电机组首选的NO_x控制技术。空气分级燃烧技术是一种基于全面燃烧调整的浓淡燃烧技术,已成为降低燃烧产物中的NOX浓度、减轻环境污染的重要手段,在锅炉改造和新锅炉机组的建设中被普遍采用。各种研究表明,分级燃烧对高挥发分煤降低NO_x生成效果明显。但对锅炉低NO_x改造还缺乏系统的研究。本文以空气分级及低NO_x燃烧器综合应用为出发点,重点在于高效低NO_x排放系统集成技术的研究、设计和应用,采用试验研究、理论研究、数学模型研究相结合的研究方式。以理论分析为基础,在冷态模化实验台上对浓淡燃烧器进行模化研究,优化设计参数;在热态试验台上进行分级供风燃烧试验研究,针对不同煤种、不同运行参数,确定合适的改造方案;研究分级燃烧污染生成数学模型,进行数值模拟研究;结合冷态模化试验和燃烧试验研究,进行改造方案优化研究。进行电站锅炉高效低NO_x燃烧优化系统设计的参数优化研究;开发关键设备;进行运行参数优化研究;研究低NO_x燃烧节能技术;高效低NO_x燃烧系统关键设备制造研究;提出了三级可控浓淡燃烧降低NO_x的综合技术集成方法,在200MW电站锅炉上进行工业应用研究;进行示范锅炉机组性能考核试验研究。结果表明:空气分级燃烧的参数对降低NO_x生成影响很大。通过采取分级燃烧的方式,能够降低NO_x。改后NO_x排放较改前降低494mg/Nm~3～508mg/Nm~3,降低了56.7%~58.3%。改后锅炉热效率为90.439%,较改造前提高了1.047%。通过连续的运行调整和观察发现,长时间连续大负荷运行时,锅炉未出现结渣、超温等情况。本文的主要创新成果为:多种技术集成与优化,形成了具有自主知识产权的空气分级低NO_X排放系统技术;将污染控制与节能技术结合,达到了高效节能;智能控制技术与低NO_X排放技术有效结合,实现了优化经济运行。本论文的工作可以指导电站锅炉的低NO_x排放技术的研究与工程应用。更多还原

【Abstract】 The pollutant come from the coal combustion already become the main source of atmosphere pollution. One of the primary factors of atmosphere pollution is NO_x from coal-fired power plants. Environmental pollution already became one of our country economy development main restriction factors, so governed NO_x emission of coal-fired power plant is become urgent mission. Considered our country take the coal-electricity as the national condition, in the present economical development situation, develop the effective low-NO_x combustion technology, will have very important social efficiency and economic efficiency in the future.The low-NO_x combustion technology is the first choice of the NO_x control technology in thermal power unit. The air staged combustion technology is one kind of rich-lean combustion technology based on the comprehensive burning adjustment, which has become the important method to reduce density of NO_x in the combustion product and reduce the environmental pollution, so it is generally used in the boiler transformation and the new boiler unit’s construction. Various research indicated that the staged combustion have obvious effect to reduce the NO_x production of high volatile matter coal. But also lack the system research to low NO_x of the boiler transformation now.The article begin with the air grading as well as the low-NO_x combustion application, focusing on the research, design and application of the high efficiency and low-NO_x emission system integration technology, with the methods of experience, theory narration, combining with mathematics model research. Based on the theory analysis, the simulated experiments to the bias burner are conducted on the cold modeling bench, while the design parameters are optimized. The air staged combustion test is carried on the hot bench, which aims at different coals and different operating parameters to determine appropriate transformation programs. Research staged combustion pollution to generate mathematical models for value simulation. Unify the cold modeling experiment and the burning test research to conduct the optimization research of the transformation programs. Carry on the utility boiler’s parameter optimization research for the combustion system design of high efficiency and low NO_x; development of key equipment; conduct the movement parameter optimization research; study the low-NO_x combustion energy conservation technology; high efficiency and low-NO_x combustion system’s key equipment manufacturers; established the ensemble method of three staged controlled rich-lean low NO_x combustion comprehensive technology, conduct the industrial application research on the 200MW power plant boiler; conduct the demonstration boiler unit performance inspection experimental study.The result indicated that the parameters of air staged combustion have a significant influence on reducing the NO_x production. It can reduce NO_x through the air staged combustion. Compared with before transformation the NO_x emission reduce 494mg/Nm3 to 508mg/Nm3 after rebuilding while the reduction rate reaches to 56.7%~58.3%. After transformation the thermal efficiency of boiler is 90.439%, which improves 1.047% compared with before transformation. Through the continual adjust operation and observe it can be discovered that the boiler is not appeared the situation such as slag-bonding, excess temperature and so on.The main innovation achievement of this article is: The system of air staged low NO_x emission which have our own independent intellectual property right is formed by various technology integrated and optimizes; it have reached high-effect energy conservation with the link of contamination control and energy-efficient technology; and it have realized optimizing economy operation with the union of intelligent control technology and low NO_x emission technology.The work of this paper may instruct the research and project application of low NO_x power plant boiler.更多还原