300mw机组过热汽温系统进行原理分析设计.doc

... 摘要本次毕业设计(论文)是通过对 300MW 机组过热汽温系统进行原理分析、可靠性论证、现场实地观察,提出的保证该系统长期稳定控制的方案。锅炉蒸汽温度自动控制包括过热蒸汽温度控制和再热蒸汽温度控制。锅炉过热蒸汽温度是影响锅炉生产过程安全性和经济性的重要锅炉过热蒸汽温度是影响锅炉生产过程安全性和经济性的重要参数, 现代锅炉的过热器是在高温、高压的条件下工作。必须通过自动化手段加以控制,维持其出口蒸汽温度在生产允许的范围内。因此, 需要采用适当的减温方式改变过热器入口的蒸汽温度。从而控制出口的过热蒸汽温度。目前大多数机组都采用二级喷水减温控制方式。在再热蒸汽温度控制中,由于蒸汽负荷是由用户决定的,所以几乎都采用改变烟气流量作为主要控制手段,例如改变再循环烟气流量,改变尾部烟道通过再热器的烟气分流量或改变燃烧器(火嘴)的倾斜角度。关键字自动控制过热蒸汽喷水减温 Abstract The design project for graduation(graduation thesis)pose a scheme which pledges the system under the coordination control long-term, by analyzing superheat steam temperature principle of 300MW unit sets,testifying the reliability and observing by doing fieldwork. Boiler steam temperature automatic control includes superheat steam temperature control and reheat steam temperature control. Boiler superheat steam temperature is an important parameter which influences boiler produce process safety and economic value. Sophisticated boiler super heater working on condition that high temperature and high pressure must be controlled by automatic methods, and keep the outlet steam temperature in the range of produce permitting. For this reason, we should use suitable desuperheat methods to alter the inlet steam temperature of superheater, so that control the outlet temperature of superheater. At the moment, most unit sets use Ⅱ jet desuperheat control. Under the reheat steam temperature control, consumers decide the steam load, so we use the gas flow as the main control method. For example, we change the gas recalculating flow and tail flue by altering the gas divergence flow of reheated or altering the gradient bustion chamber. Key words: A utomatic Control Superheat steam Jet desuperheat 目录摘要............................................................................................................................................. 1 ABSTRACT ......................................................................................................................................... 2 第一章引言.