A forecast for the environmental effect of pressure-retarded osmosis on CO2 emissions from seawater reverse osmosis in Korea: a scenario-based study

Abstract

Seawater reverse osmosis (SWRO) has played a key role in alleviating water stress worldwide. However, its intensive energy consumption, which is highly dependent on fossil fuels, needs to be reduced to mitigate the CO2 emissions resulting from SWRO. Many technologies, including pressure-retarded osmosis (PRO), have been applied in an attempt to reduce the energy consumption of SWRO. In this study, potential trends in CO2 emissions from SWRO processes in Korea are considered based on SWRO operational data collected from a range of sources and relating to societal scenarios of the future. These societal scenarios are based on current population trends in Korea and the proportion of renewable energy currently utilized in Korea. Next, using a dimensionless performance index for the SWRO-PRO hybrid process, the study presents the potential efficacy of PRO in reducing the magnitude of CO2 emissions from SWRO processes in Korea. The analysis shows that CO2 may be reduced by 10%–40%. The results of the study suggest a promising role for PRO as a suppressor of CO2 emissions. It is anticipated that the study will facilitate further in-depth studies into the use of PRO.