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.