Optimal operation of brackish water reverse osmosis desalination plant

This work analyses the optimal plant operation of brackish water reverse osmosis (BWRO) desalination, to reduce the specific energy consumption. Model-based optimisation was developed to guide RO operation, with the modelling results validated by plant data. A comprehensive mathematical model based on first principles, which explicitly accounts for membrane area and hydraulic permeability, pump characteristic curves, and pressure drops along the RO train, has been developed and validated using plant data. A constrained nonlinear optimisation is formulated and solved for two RO trains with different service times. It is shown that a 16% reduction in specific energy consumption (SEC) is possible by optimising operating conditions within the normal operating range of the pump while maintaining the same permeate rate. The results are discussed using previously derived dimensionless parameters, and suggestions are made to further reduce the specific energy consumption in BWRO plant operation. Source: workingwithwater.filtsep.com