... bed, precision filter, water (equal to or more than 18m Omega.CM) (traditional process). (2)Pretreatment, anti penetration, intermediate water ... m precision filter, water (equal to or more than 17m Omega.CM) (the latest Technology). (5)Pretreatment system, reverse osmosis ... device, precision filter, water (equal to or more than 15m Omega.CM) (traditional process) the above process have the advantage, ...