A spatiotemporal model for dynamic RO simulations

A spatiotemporal model is developed for dynamic simulations of RO desalination. The model explicitly accounts for pressure drop, concentration polarization and axial dispersion along the pressure vessels. A detailed numerical method, which is based on orthogonal collocation on finite elements in the spatial domain, is presented to solve the coupled partial differential equations (PDEs) in the model. Two examples, RO with periodic feed flow reversal and membrane flushing with/without permeation flux in batch operations, are used to demonstrate the applications of the proposed model. The simulation indicates that salt concentration overshoots during feed flow reversal. For batch operations, flushing efficacy is significantly improved if permeate flux is turned off during the flushing period.

Automated summary

A spatiotemporal model is developed for dynamic simulations of RO desalination, taking into account factors such as pressure drop and concentration polarization. The model uses a numerical method based on orthogonal collocation on finite elements to solve coupled partial differential equations. Examples of RO with periodic feed flow reversal and membrane flushing in batch operations demonstrate the model's applications, revealing insights into salt concentration overshoot and the impact of turning off permeate flux during flushing.