California-based Clean Filtration Technologies (CFT) has raised USD1.5m in a first tranche of funding led by Dow Chemical. The firm plans to raise a further USD1.5m before the round closes later this year. CFT develops water treatment technology. Its hydroclone system is a water filtration device which reduces suspended solids from difficult-filter water for use in industrial processing and agricultural irrigation. The firm aims to begin producing commercial volumes of the system in the second half of this year.