Process and apparatus for removing dissolved iron from water

Claim 1

A process for removing from water soluble and/or dispersed iron, which comprises the steps of: (1) aerating the water to introduce oxygen into solution therein under high frictional energy in a sufficient amount to form colloidally dispersed iron hydrates having a surface charge from substantially all of the dissolved and/or dispersed iron present; (2) maintaining the aerated water under a pressure within the range from about 10 to about 500 psig; (3) passing the aerated water under a pressure within the said range through a mass of particulate material having a surface charge and a particle size above about 0.25 mm capable of attracting, removing and collecting the dispersed iron hydrates; and (4) recovering water containing less iron than the starting water.

Claim 14

An apparatus for removing from water soluble and/or dispersed iron, comprising, in combination: (1) means for aerating the water to introduce oxygen into solution therein under high frictional energy in a sufficient amount to form colloidally dispersed iron hydrates having a surface charge from substantially all of the dissolved and/or dispersed iron present; (2) means for maintaining the aerated water under a pressure within the range from about 10 to about 500 psig; (3) a bed of particulate material having a surface charge and a particle size above about 0.25 mm capable of attracting, removing and collecting the dispersed iron hydrates; (4) means for passing the aerated water under a pressur within said range through the said bed; and (5) means for delivering water containing less iron than the starting water.

Claim 15

An apparatus for removing from water soluble and/or dispersed iron, comprising, in combination: (1) means for aerating the water to introduce oxygen into solution therein under high frictional energy in a sufficient amount to form colloidally dispersed iron hydrates having a surface charge from substantially all of the dissolved and/or dispersed iron present; (2) means for maintaining the aerated water under a pressure within the range from about 10 to about 500 psig; (3) a bed of particulate material having a surface charge and a particle size above about 0.25 mm capable of attracting, removing and collecting the dispersed iron hydrates; (4) means for passing the aerated water under a pressur within said range through the said bed; and (5) means for delivering water containing less iron than the starting water.

Claim 21

An apparatus according to anyone of claims 13 to 18 in which the device is a succession of two to six converging nozzles followed by expansion chambers having means introducing air or water in controlled amounts into the first expasion chamber at the first nozzle, and mixing air and water under conditions developing high frictional energy and successive compression/decompression at each nozzle in series, with a rapid dis- solutuion of the air in the water.

Claim 22

An apparatus according to anyone of claims 13 to 19 in which the means for aerating the water comprises a pump, an injector nozzle downstream of the pump, and an airintake valve comprising a spring-loaded check valve on the suction side of the pump, and means controlling the amount of airtaken in by the valve.

Claim 23

An apparatus according to anyone of claims 13 to 20 including a waterholding tank in line between the ! aerating means and the bed of particulate material, maintaining the pressure within the range from about 10 to about 500 psig.

Claim 25

An apparatus according to anyone of claims 13 to 22 in which the particulate material is a material which tends to wear away under the action of the water flowing through the mass, thereby increasing the surface area as the flow continues.

Claim 26

An apparatus according to anyone of claims 13 to 23 in which the particulate material is porous or rough-surfaced.

Claim 27

An apparatus according to anyone of claims 13 to 24 in which the particulate material is compressed into shaped aggregates from smaller particles.

Claim 28

An apparatus according to anyone of claims 13 to 25 in which the particulate material is a silica, an aluminum- ilicate, a magnesium silicate,an alumina, a calcium carbonate or carbon.

Claim 29

An apparatus according to anyone of claims 13 to 25 in which the particulate material is selected from the group consisting of silica, sand, bentonite, fuller's earth, kaolin, diatomaceous earth, feldspar, marble, partially calcined limestone, perlite, pumice, lava, magnesium silicate, talc, alumina, magnesium aluminum oxide, bauxite, dolomite, limestone, partially calcined dolomite, magnesia, coke, bituminous charcoal and activated carbon.

Claim 30

An apparatus for aerating water containing water soluble and/or dispersed iron to introduce air into solution therein under high frictional energy in a sufficient amount to form colloidallly dispersed iron hydrates having a surface charge, comprising, in combination: (1) a housing having an inlet for water; an inlet for air; and an outlet for aerated water; ; (2) a chamber in the housing for mixing water and air and producing aerated water; (3) first, second and third fluid flow passages in the housing interconnecting the water inlet, the air inlet and the aerated water outlet, respectively, with the chamber; (4) jet means in one of the first and second fluid flow passages for projecting a high velocity jet flow of water or air into the chamber across the inlet into the chamber of the second or first fluid flow passage, respectively, in a manner to draw air or water from that passage into the chamber and into th high velocity jet flow and obtain violently turbulent mixing thereof to form a high velocity turbulent flow of aerated water; (5) means for controlling the volume amount of at least one of the flows of water and air into the chamber to control the amount of air dissolved in the aerate water and the turbulence of the mixing; (6) diffuser means receiving the flow of aerated water from the chamber and delivering it. to the aerated water outlet of the housing; and (7) means for maintaining the fluids throughout their passage through the housing under a pressure within the range from about 10 to about 500 psig.

Claim 31

An apparatus for aerating water containing water soluble and/or dispersed iron to introduce air into solution therein under high frictional energy in a sufficient amount to form colloidallly dispersed iron hydrates having a surface charge, comprising, in combination: (1) a housing having an inlet for water; an inlet for air; and an outlet for aerated water; ; (2) a chamber in the housing for mixing water and air and producing aerated water; (3) first, second and third fluid flow passages in the housing interconnecting the water inlet, the air inlet and the aerated water outlet, respectively, with the chamber; (4) jet means in one of the first and second fluid flow passages for projecting a high velocity jet flow of water or air into the chamber across the inlet into the chamber of the second or first fluid flow passage, respectively, in a manner to draw air or water from that passage into the chamber and into th high velocity jet flow and obtain violently turbulent mixing thereof to form a high velocity turbulent flow of aerated water; (5) means for controlling the volume amount of at least one of the flows of water and air into the chamber to control the amount of air dissolved in the aerate water and the turbulence of the mixing; (6) diffuser means receiving the flow of aerated water from the chamber and delivering it. to the aerated water outlet of the housing; and (7) means for maintaining the fluids throughout their passage through the housing under a pressure within the range from about 10 to about 500 psig.

Claim 35

An apparatus according to anyone of claims 28 to 31 comprising a succession of two to six converging nozzles followed by expansion chambers having means introducing air or water in controlled amounts into the first expansion chamber at the first nozzle, and mixing air and water under conditions developing high frictional energy and successive compression/decompression at each nozzle in series, with a rapid dissolution of the air in the water.

Claim 36

An apparatus according to anyone of claims 28 to 32 in which the jet means is arranged in the first fluid flow passage for projecting a jet flow of water. ;

Claim 37

An apparatus according to anyone of claims 28 to 32 in which the jet means is arranged in the second fluid flow passage for projecting a jet flow of air.