燃煤发电机组机炉耦合系统经济性的对比分析

Comparison on Economic Performances of Boiler-Turbine Coupling Systems for Coal-fired Power Plants

为了研究燃煤发电机组机炉耦合系统的经济性,以某典型660 MW超超临界燃煤机组为例,建立了节煤收益与系统投资模型,对常规低压省煤器系统、采用暖风器的机炉耦合系统以及设置旁路烟道的机炉耦合系统等3种机炉耦合系统的经济性进行了对比分析。计算结果表明:在相同的边界条件下,3种机炉耦合系统的净节能效果分别可以达到1.60,2.64和3.32 g/(kW·h),系统换热设备投资分别为530,1 146和1 177万元,系统的年节煤净收益分别达到了307,501和636万元;常规低压省煤器系统的投资最低,但是节能效果最差;采用暖风器的机炉耦合系统的节能效果有所提高,但是系统投资高;设置旁路烟道的机炉耦合系统的经济性最优。

In order to evaluate the economy of turbine-boiler coupling system of coal-fired power units,a typical 660 MW ultra-supercritical coal-fired power unit was taken as the reference case,economic performances on three coupling systems,i.e.,conventional low-pressure economizer system,coupling system with air heater and coupling system with bypass flue,were analyzed comparatively by developing the models of coal-saving benefits and system investments.With the same boundary condition,the calculation results show that the net energy-saving effects of the three types of boilers coupling systems can reach 1.60,2.64 and 3.32 g/(kW·h),respectively.The system investments for heat exchangers are 5.30,11.46 and 11.77 million yuan,respectively.The annual net coal-saving benefits of the system are 3.07,5.01 and 6.36 million yuan,respectively.Among three coupling systems,the conventional low-pressure economizer system has the lowest system investment,while the energy-saving effect is the worst;both the system energy-saving effect and the investment have increased in coupling system with air heater.The economic performances of boiler-turbine coupling system with bypass flue is the best.