基于燃煤机组供热改造方案技术经济性研究

目的  为了解决目前燃煤机组面临的电负荷与热负荷矛盾突出的问题，保障机组冬季热源供给，有必要进行破除其热电耦合关系的供热改造方案的研究。 方法  对某类型300 MW燃煤机组的两种供热改造方式进行模型分析，比较机组改造前后的供热量等数据，研究符合生产条件的热电解耦供热改造方案。总结出了热电联产机组供热改造的经济效果。 结果  通过文中供热模型分析可知，燃煤机组仅靠抽汽进行供热，受电负荷制约很大，高电负荷时供热量为低电负荷时的2～3倍。当电负荷受限严重时，其供热量无法满足冬季供热需求。但机组经过高背压改造、切缸改造后，调峰能力增强，相同电负荷下其供热量增加到原来的3～4倍，有效解决了这一问题。 结论  文章研究成果对今后相同类型的燃煤机组供热改造具有借鉴意义。

Technical and Economic Study on Heating Transformation Scheme of Coal-Fired Units

  Introduction  In order to solve the prominent contradiction between electric load and heat load faced by coal-fired units and ensure the heat source supply of units in winter, it is necessary to study the heating transformation scheme to break its thermoelectric coupling relationship.   Method  This paper made a model analysis of two heating transformation modes of a type of 300 MW coal-fired unit, compared the heating capacity and other data before and after the unit transformation, and studied the thermoelectric decoupling heating transformation scheme in line with the production conditions. And the economic effect of heating transformation of cogeneration units was summarized.   Conclusion  Through the analysis of the heating model in this paper, it can be seen that the coal-fired unit only relies on steam extraction for heating, which is greatly restricted by the power load. The heating capacity at high power load is 2～3 times that at low power load. When the electric load is severely limited, its heating capacity cannot meet the heating demand in winter. But after retrofit of high back pressure and modification of the cylinder, the capacity of peak shaving increases, and the heating capacity increases to 3～4 times under the same electric load, which effectively solved the problem.   Result  The research result can be used as a reference for the heating transformation of the same type of coal-fired units in the future.