基于等效焓降法的锅炉尾部烟气热量深度利用系统热效率研究

Research on Thermal Efficiency of Advanced Utilization Systems of Boiler Tail Flue Gas Heat Based on the Equivalent Enthalpy Drop Theory

摘要: 介绍了目前较常用的两种锅炉尾部烟气热量深度利用系统。通过等效焓降法对两种系统进行了理论研究，推导出热效率公式，结合某1 GW等级超超临界机组THA工况，应用等效焓降法对两种系统进行了定量计算和比较，结果表明：在一定的工程边界条件和设计原则下，空气预热器旁路烟道系统更好地提升了烟气热量利用能级，热效率较高，节能效益较好。

Abstract: The two usual advanced utilization systems of boiler tail flue gas heat at present was introduced. The two systems were studied by the equivalent enthalpy drop theory, the thermal efficiency formula was deduced. Referring to THA condition of a 1 GW USC unit, the equivalent enthalpy drop theory was used for quantitative calculation and comparison of the two systems, the results show that: based on certain boundary conditions of the project and design principles, air preheater flue gas bypass system perfectly increases flue gas heat energy level, and that has better thermal efficiency and great energy-saving effects.