回收烟气余热亚临界ORC系统投资回收年限估计

Payback Period Estimation of Subcritical Organic Rankine Cycle System for Waste Heat Recovery from the Flue Gas

建立了回收低温烟气余热的有机朗肯循环系统投资回收年限计算模型,并以最短投资回收年限为目标对内部参数进行了优化,分析了外部参数对投资回收年限的影响。结果表明,随着蒸发温度、冷凝温度、蒸发器和冷凝器节点温差的增加,系统投资回收年限均先减小后增大,即存在一组最佳工作参数使回收年限最短。提高烟气进口温度和流量都可有效缩短投资回收年限。采用R245fa作为循环工质可使系统同时具有较短的回收年限和较大的净输出功。

Established a theoretical model which is used to evaluate the payback period of subcritical organic Rankine cycle system for waste heat recovery from the flue gas. The internal parameters optimization is performed based on the minimum payback period. In addition,the effects of the external parameters on the payback period are analyzed. The results showed that the payback period decreases first,then increases with the increase of the evaporating temperature, condensing temperature and pinch point temperature differences in the evaporator and condenser. Therefore,there exists a grouP〈0of the internal parameters leading the minimum payback period. Meanwhile,with the increase the inlet temperature and flow rate of flue gas,the payback period decreases. When R245 fa is selected as the working fluid,the ORC system exhibits the short payback period and more net output power.