Thermal associated pressure-retarded osmosis processes for energy production: A review

Climate change is an existential threat to global environments and human life. To achieve global mean temperature rise of below 1.5 degrees C, increasing utilization of renewable energy and minimizing CO2 emission from fossil fuel industries have been emphasized by the United Nations. Pressure-retarded osmosis (PRO) has displayed its technical feasibility in capturing renewable energy from the salinity gradient of two streams through a semipermeable membrane. Towards achieving economic feasible PRO, process optimization, waste stream/heat utilization, and hybrid PRO processes have been attempted by theoretically modelling and experimental examination. Among these efforts, the thermal associated PRO processes have received great attention due to their improved power generation. In this paper, we aim to provide a comprehensive review on thermal associated PRO processes, focusing on the role of thermal behaviour in both stand-alone PRO and hybrid PRO processes (e.g. PRO-membrane distillation, PRO-thermosiphon, PRO-solar pond). Meanwhile, thermal associated draw solution development has been highlighted. Finally, a combination of PRO with high temperature/high pressure geothermal waste gas as draw solution is proposed and its technical and economic feasibility is discussed, especially under Icelandic scenario. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

This paper discusses the threat of climate change to global environments and human life, emphasizing the need to reduce CO2 emissions from fossil fuel industries and increase the utilization of renewable energy. Pressure-retarded osmosis (PRO) has been shown to capture renewable energy from the salinity gradient of two streams. The study focuses on thermal associated PRO processes, particularly looking at the role of thermal behavior in standalone PRO and hybrid PRO processes.