Abstract: An apparatus is provided for removing impurities such as iron compounds from water, which comprises:(1) an injector-mixer for colloidalizing the iron compounds in water under conditions of high shear and decompression/compression to finely divide existing insoluble iron hydrates, and by dissolution in the water of air in sufficient amount to oxidize and form colloidally dispersed iron hydrates from the dissolved iron present, thereby providing substantially all of the iron in the form of micelles having a surface charge;(2) a pressurizer for maintaining the water under a pressure within the range from about 10 to 500 psig;(3) a bed of particulate material having a surface charge capable of attracting, removing, and collecting the dispersed iron hydrates; and(4) a backwash system for removing the impurities collected throughout the mass of particulate material.

Abstract: A process is provided for removing impurities such as iron compounds from water, which comprises the steps of:(1) colloidalizing the iron compounds in water under conditions of high shear and decompression/compression to finely divide existing insoluble iron hydrates, and by dissolution in the water of air in sufficient amount to oxidize and form colloidally dispersed iron hydrates from the dissolved iron present, thereby providing substantially all of the iron in the form of micelles having a surface charge;(2) maintaining the water under a pressure within the range from about 10 to 500 psig;(3) then passing the water under a pressure within said range through a mass of particulate material having a surface charge capable of attracting, removing, and collecting the dispersed iron hydrates; and(4) recovering water containing less iron than the starting water, and preferably less than 0.3 PPM of iron.