Studies on the Performance of Organic Rankine Cycle Applied to Low Temperature Heat Source below 100℃

Abstract

In this study, the performance of Organic Rankine Cycle (ORC) applied to low temperature heat source was investigated to provide meaningful information and better understanding on ORC. In previous studies of ORC, the types of heat source were mainly geothermal heat, solar heat, biomass combustion waste heat whose temperatures range from 150℃ to 350℃. However, although waste heat below 100℃ generated from industrial process (e.g. food, beverage, fiber industry) and PEM fuel cell has a large portion of overall waste heat, it isnt sufficiently utilized for waste heat recovery. Therefore, it is necessary to investigate operating characteristics of ORC using waste heat from heat source under 100℃. In order to verify the performance of ORC applied to heat source below 100℃, experiment was conducted to investigate the effects of some key parameters (e.g. evaporation pressure, condensation pressure, mass flow rate, etc.) and the optimal operating condition which has maximum generation work. Results show that the maximum generation work was about 234 W and the thermal efficiency of ORC was about 4%, when the range of heat input was from 3 kW to 6 kW. By experiment of ORC applied to low temperature heat source, it was confirmed that ORC can obtain the additional generating power from waste heat under 100℃.