Abstract:

Organic Rankine cycle(ORC) and Kalina cycle are both promising ways for low temperature waste heat utilization, and these two technologies have their own advantages and disadvantages on using waste heat. In refineries, there is considerable waste heat. It is significant to choose a proper cycle system considering different waste heat sources for efficient utilization of energy. Thermal efficiency and exergy efficiency are two key parameters to evaluate energy performance of power cycle systems. In this paper, the waste heat sources are classified into three types(i.e., sensible heat source, combined heat source and latent heat source). An organic Rankine cycle and a Kalina cycle for low waste heat recovery are simulated by Aspen Hysys considering the characteristics of waste heat sources. The results show that when the waste heat is sensible heat source, the energy performance of Kalina cycle is better than that of ORC, while when waste heat is combined heat source and the ratio of latent heat source and sensible heat source(R) is equal to 1 or when waste heat is latent heat source, the energy performance of ORC is better than that of Kalina cycle.

Key words: organic Rankine cycle, Kalina cycle, waste heat sources, energy performance, computer simulation, recovery, thermodynamic properties

摘要：

有机朗肯循环和卡琳娜循环都是发展前景广阔的低温余热动力利用技术，这两种技术在余热利用方面各有其优势和劣势。在炼厂中，余热资源分布广泛，针对不同余热热源选择合适的动力循环系统对能量的有效利用具有实际意义。热效率和(火用)效率是评价动力循环系统的两个重要指标。通过将余热资源分成3类，即显热热源、复合热源和潜热热源，用Aspen Hysys软件对有机朗肯循环和卡琳娜循环进行流程模拟，考察了余热资源特性对有机朗肯循环和卡琳娜循环能量性能的影响。结果表明当余热为显热热源时，卡琳娜循环系统优于有机朗肯循环；当余热为复合热源且潜热与显热比R=1或当余热为潜热热源时，有机朗肯循环优于卡琳娜循环。

关键词: 有机朗肯循环, 卡琳娜循环, 余热资源, 能量性能, 计算机模拟, 回收, 热力学性质