A novel spiral wound module design for harvesting salinity gradient energy using pressure retarded osmosis

Pressure retarded osmosis (PRO) is an evolving form of a renewable energy process which utilizes the salinity gradient energy from two solutions of different concentrations. One of the main problems limiting the appli-cation of PRO is the low performance of the commercially available spiral-wound modules which have poor flow distribution and high pressure drop. The present paper proposes a new spiral-wound module design for PRO application. The performance of the new module design was investigated numerically and compared with the available spiral-wound module. Compared to the available module, the power density of the new design was higher by 25% and 15% at draw concentrations of 35 g/kg and 60 g/kg respectively, while there was a 35% decrease in the pressure drop. The new spiral-wound module design presents an enhanced overall performance due to the better flow distribution and lower pressure drop, yielding a higher water flux and power density.

Automated summary

Pressure retarded osmosis (PRO) is a renewable energy process that utilizes the energy from a salinity gradient between two solutions. However, the commercially available spiral-wound modules used in PRO have poor flow distribution and high pressure drop, limiting their application. This study proposes a new spiral-wound module design that improves overall performance with better flow distribution, lower pressure drop, and higher power density.