Comparative study of waste heat steam SRC, ORC and S-ORC power generation systems in medium-low temperature

For Steam Rankine Cycle (SRC), Organic Rankine Cycle (ORC) and Steam-Organic Rankine Cycle (S-ORC) power systems, in this paper, mathematical models are developed to explore the feasibility that combines the fluid-low temperature (150-350 degrees C) waste heat steam and low-boiling point organic working fluids for power generation. Using the numerical models, we calculate and compare thermal efficiency, exergy efficiency, operation pressure, generating capacity, etc. of three power systems, namely SRC, ORC and S-ORC under the same heat source conditions. The results show that under the condition of 150-210 degrees C heat source, ORC has the highest thermal efficiency, exergy efficiency and power generation; while at 210-350 degrees C, the performance of the S-ORC has a distinct advantage. Its thermal efficiency and exergy efficiency are higher than those of the SRC and ORC power systems. (C) 2016 The Authors. Published by Elsevier Ltd.