电站锅炉对流受热面积灰在线监测

发布时间：2018-03-01 19:01

本文关键词： 燃煤锅炉对流受热面积灰在线监测烟气阻力　出处：《太原理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：电站锅炉运行的安全性和经济性受很多因素影响,其中锅炉受热面积灰是影响锅炉安全经济运行的一个主要因素。燃煤电厂锅炉受热面的积灰使传热热阻增加、换热量减少,直接导致锅炉排烟温度升高、锅炉热效率降低。同时锅炉受热面积灰会导致烟道的通风阻力增加,使得引风机电耗增加,降低了机组供电效率,严重时将导致机组降负荷运行或者停机,甚至酿成重大事故。在各种避免严重积灰的技术措施中,对受热面进行积灰吹扫是一种有效而且普遍采用的手段。目前,我国的大型电站锅炉均装备了各种可靠的吹灰装置,绝大部分电厂采取定时吹灰,由此带有一定的盲目性和不经济性。这是因为电站锅炉的燃用煤种经常发生变化,按设计煤种制定的吹灰规程就不适用了,出现了吹灰要么过于频繁要么不足,导致运行经济性和安全性降低。基于受热面积灰与烟气流动阻力之间的关系,本文提出了一种新的直接监测受热面积灰厚度的方法。针对600MW亚临界机组,依据其尾部各对流受热面的结构和烟气流动阻力在线计算各受热面的积灰厚度,计算结果显示该方法的可信度高。以VB为开发工具,编制了锅炉尾部烟道对流受热面积灰厚度在线计算软件,包含烟气、空气、水和水蒸气物性计算的类模块。锅炉尾部烟道对流受热面积灰厚度在线监测方法已授权国家发明专利,目前,该技术正在国电大同发电有限公司600MW机组上实施。
[Abstract]:The safety and economy of boiler operation are affected by many factors, among which the ash deposit on boiler heating surface is one of the main factors affecting the safe and economical operation of boiler. The ash deposition on boiler heating surface of coal-fired power plant increases heat transfer resistance and decreases heat transfer. At the same time, ash accumulation on the heating surface of the boiler will increase the ventilation resistance of the flue, increase the power consumption of the induced fan, and reduce the power supply efficiency of the unit. In the technical measures to avoid serious soot deposition, soot blowing on the heating surface is an effective and widely used means. Large power plant boilers in China are equipped with various reliable soot blowing devices. Most power plants adopt regular soot blowing, which has certain blindness and diseconomy. This is because the burning of coal for utility boilers often changes. The soot blowing code based on the design coal type is not applicable, and the soot blowing is either too frequent or insufficient, resulting in lower operation economy and safety. Based on the relationship between soot deposition on heating surface and flue gas flow resistance, In this paper, a new method for directly monitoring the ash thickness of heating surface is proposed. For 600 MW subcritical unit, the ash thickness of each heating surface is calculated on-line according to the structure of each convection heating surface and the resistance of flue gas flow at the tail of 600 MW subcritical unit. The calculation results show that the method has high reliability. With VB as the development tool, the on-line calculation software of ash thickness on the convection heating surface of boiler tail flue is developed, which includes flue gas and air. The on-line monitoring method of ash thickness on convection heating surface of boiler tail flue has been authorized the national invention patent. At present, the technology is being implemented on 600MW unit of Datong Power Generation Co., Ltd.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM621.2

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