Modelling and simulation of a batch reverse osmosis process using modelica

Batch operation of reverse osmosis (RO) has emerged as a promising strategy for enhancing energy efficiency and reducing fouling in seawater and brackish water desalination applications. This study implements a transient numerical model using Modelica to investigate the behavior of a batch seawater RO (BSWRO) system. The feed solution volume decreases and its salinity increases with time. It is pressurized by pumping product water into the other side of a piston. The model incorporates features such as the feed solution residence time in the inlet and outlet piping and captures the local variation in flux and concentration polarization over the membrane area. The instantaneous power consumption of the high-pressure and circulation pumps is calculated. The ease of adoption of Modelica underscores its utility in simulating complex transient and non-linear phenomena. The developed model can be expanded in the future to answer questions related to optimal control of batch RO systems.