water treatment system to filtrate water to make purified water, mineral water,etc. pretreatment :1) first we draw out tap water by water pump, then get ... ion ,such as calcium, magnesium ion .4) Ultra-filtration and Micro-filtration: use PVDC or macromolecule material , you know ,it ... treatment or we call it RO( reverse osmosis) could remove salt, metal ion and microbe in water .terminal treatment :1) ...