A Working Fluid Assessment for a Biomass Organic Rankine Cycle under Different Conditions

Abstract

Many thermal resources are not reasonably used in the chemical industry’s production process. To recover the waste heat from organic waste residue-calcium carbonate (CaCO3), which is added to inhibit hydrogen production, an organic Rankine cycle (ORC) system is applied in this research. An ORC system can reuse the low-temperature waste heat that is not fully utilized. In this study, the mathematical model of the biomass ORC power generation system is constructed. Five organic working fluids, R11, R113, R123, R141b, and R245fa, were selected from the physical characteristics and safety of working fluids. The system application case is the low-temperature heat absorption in a chemical industry’s production process. The system is simulated by Aspen Plus V11 software, so as to study and analyze the influence of different working fluids and working conditions on the system performance and to obtain the preferred working fluids under different working conditions. At the same time, the economic evaluation and entropy method of the system are evaluated by using the investment profit rate PRI from different angles. It can be found that R11 and R141b have advantages, but R11 does not have advantages in environmental aspects. Through research, it is found that it is difficult to have a working fluid that can adapt to the biomass ORC power generation system under any working conditions. This paper can provide a basis for the subsequent research and selection of working fluids in the biomass ORC system.