洋上水素製造システムのための海水濾過処理技術に関する研究

抄録

　There has been a trend toward decarbonization and carbon neutrality and the development of energy production technologies that do not generate carbon dioxide is being promoted. One such production technology is green hydrogen production. Specifically，possible measures include supplying the electricity used for hydrogen production from renewable energy sources such as offshore wind power，and filtering seawater to obtain the pure water necessary for hydrogen production in order to avoid competition with domestic water supplies.

　This study examined an offshore hydrogen production plant that uses electricity generated by offshore wind power to filter seawater using the RO method to obtain pure water，and then produces hydrogen by electrolysis.

　Furthermore，a challenge with RO is membrane fouling caused by raw water quality，which hinders maintaining flow rates and extending membrane lifespan. A solution requires pretreatment to improve raw water quality.

　This study clarified the applicability of a filtration method using a spring filter and diatomaceous earth as a filtration aid (hereafter referred to as the SP/DE method) as seawater pretreatment for RO filtration. The technology for seawater filtration to obtain pure water suitable for hydrogen production was investigated by combining the SP/DE method with high-pressure/low-pressure RO methods. This technological investigation involved designing a filtration system and conducting filtration experiments using the system. Both lake water and seawater were used as feedwater.