摘 要
摘 要
目前，我国的电厂大多数是火力发电厂，煤是发电的主要燃料，锅炉燃烧是发电的重要环节之一。我们要以最经济的方式来利用有限的能源，这就要求我们寻找燃烧的最优方案。
本文在对国内外锅炉控制现状、发展趋势分析的基础上，研究了燃煤锅炉燃烧系统的自动控制问题。分析了燃烧控制系统的热工控制结构特点，为更大范围符合锅炉燃烧的要求，提高燃烧自动的控制系统的利用率，是在按照传统燃烧自动控制结构设计的基础上优化实现的。燃烧控制系统是一个复杂的综合性控制系统，从控制理论上讲，它可为是多输入/多输出的多变量控制系统。它由六个子系统构成：燃料控制系统、磨煤机一次风量控制系统、磨煤机出口温度控制系统、一次风压力控制系统、二次风量控制系统和炉膛压力控制系统。在设计中，利用相应的控制规律和控制器进行优化设计，达到燃烧的最优化。锅炉燃烧集经济性、安全性于一身,并针对直吹式煤粉炉燃烧控制系统进行了分析,设计出可行性方案。
关键词：直吹式制粉锅炉; “W” 型火焰燃烧器; 燃烧控制
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ABSTRACT
At present, most power plant in our country is thermal power, coal is the main energy resource and the combustion is an important part. We should use the limit resource by the way of economy. So we must to find an optimum scheme.
Based on the analysis of the present situation and development trend of boiler control domestic and overseas and long-time study experiments, plant boiler is researched in this paper. The problem of automatic control for coal-fired boiler combustion system is discussed in this thesis. The structure characteristics of burning control system are analyzed. In order to accord with the boilder burning requirements of more scope, and improve the utilization of the burning. On the basic of the traditional structure it is designed for the optimuming of burning automation. The brum boiler burning control system is a complicated and synthetical control system. On control field ,we call it multiple input multiple output and multiple parameter control system. It is made up of six subsystem：Fuel control system, A wind mill control system, Mill outlet temperature control system, An air pressure control system, Secondary air flow control system and The furnace pressure control system. In this design, we applying some control principles and control appliances to find the most economic scheme to achieve optimum combustion, then make the burn boiler burning system have both safety and economy. Take the direct-blowing boiler combustion system as a example to analyse.
Keywords:Direct- blowing boiler;W-flame burner;Combustion control
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目 录
目 录
摘 要 .............................................................................................................................................. I ABSTRACT ........................................................................................................................................ II 第1章 绪 论 ........................................................................................................................... 1 1.1锅炉燃烧控制的发展概述 ................................................................................................... 1 1.2本课题研究的内容和意义 ................................................................................................... 2 第2章 600MW机组的燃烧系统及其与设备 ........................................................................... 4 2.1燃烧系统的工作过程 ........................................................................................................... 4 2.2制粉系统及其设备 ............................................................................................................... 6 2.2.1制粉系统 ......................................................................................................................... 6 2.2.2制粉系统的主要设备 ..................................................................................................... 6 2.3燃烧设备 ............................................................................................................................. 10 2.3.1煤粉炉的炉膛 ............................................................................................................... 10 2.3.2燃烧器 ........................................................................................................................... 11 2.4风机 ..................................................................................................................................... 12 第3章 燃烧控制系统的设计 ................................................................................................... 13 3.1概述 ..................................................................................................................................... 13 3.1.1燃烧过程控制任务 ....................................................................................................... 13 3.1.2燃烧过程调节量 ........................................................................................................... 13 3.1.3燃烧过程控制特点 ....................................................................................................... 14 3.2燃料控制系统 ..................................................................................................................... 15 3.2.1燃料调节系统 ............................................................................................................... 15 3.2.2燃料调节——测量系统 ............................................................................................... 16 3.2.3给煤机指令 ................................................................................................................... 17 3.3磨煤机一次风量、出口温度控制系统 ............................................................................. 17 3.3.1磨煤机一次风量控制系统 ........................................................................................... 17 3.3.2磨煤机出口温度控制系统 ........................................................................................... 18 3.4一次风压力控制系统 ......................................................................................................... 19 3.5二次风（送风）控制系统 ................................................................................................. 23 3.5.1总风量调节——测量系统 ........................................................................................... 23 3.5.2烟气含氧量调节及偏差限制系统 ............................................................................... 24 3.5.3送风调节系统 ............................................................................................................... 26 3.6炉膛压力控制系统 ............................................................................................................. 27 结 论 ........................................................................................................................................... 31 参考文献 ....................................................................................................................................... 32
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