Air driven rotating biological contactor apparatus

Claim 2

A biological wastewater treatment apparatus, comprising: a treatment tank having a fluid inlet and a fluid outlet, a generally circular rotating biological contactor assembly mounted for rotation about a horizontal axis and disposed in said tank for partial submergence in the wastewater in the tank, a plurality of pockets arrayed along the length of said contactor assembly and disposed at the radially outer surfaces of said contactor assembly, said pockets having a depth which is a minor portion of the radius of said contactor assembly, a source of oxygen containing gas under pressure, and a gas conduit leading from said source of gas into said tank and having submerged openings disposed beneath the length of said contactor assembly, said pockets each opening outwardly in a direction opposite to the direction of rotation of said contactor assembly to trap gas released froom said conduit.

Claim 3

A biological wastewater treatment apparatus in accordance with claim 1, wherein said contactor assembly comprises a plurality of flat, circular discs closely spaced along said horizontal axis, and said pockets are disposed about the periphery of selected, non-adjacent ones of said discs.

Claim 4

A biological wastewater treatment apparatus in accordance with claim 2, wherein said pockets surround the entire periphery of eVery other one of said discs.

Claim 5

A biological wastewater treatment apparatus in accordance with claim 3, wherein said pockets are formed on a plurality of identical arcuate members each including spaced radially inwardly directed flanges which receive the outer edge of a disc and are joined thereto.

Claim 6

A biological wastewater treatment apparatus in accordance with claim 1, wherein said contactor assembly comprises an array of disc elements juxtaposed along said horizontal axis, and having a plurality of spaced, radially directed, discrete passages open at the periphery of said disc elements, and a series of internal, generally concentric, discrete passages open at each end to a radially directed passage, and said pockets extend along the perimeter of each disc element between the peripheral openings of the radially directed passages.

Claim 7

A biological wastewater treatment apparatus in accordance with claim 5, wherein said radially directed passages are equally spaced about said disc elements, and said pockets are formed on a plurality of identical arcuate members.

Claim 8

A biological wastewater treatment apparatus in accordance with claim 6, wherein each of said disc elements is comprised of a pair of identical, thin wall, formed sheets joined face to face with a peripheral flange extending between the peripheral openings of said radially directed passages, and said arcuate members each include a pair of spaced radially inwardly directed flanges which receive and are joined to the flange of said disc elements.

Claim 9

A biological wastewater treatment apparatus in accordance with claim 5, wherein each of said disc elements is comprised of a circular, thin wall, flat sheet and a circular, thin wall, formed sheet joined to said flat sheet and abutting against the flat sheet of the adjacent disc element.

Claim 10

A biological wastewater treatment apparatus in accordance with claim 5, wherein said radial passages of each disc element are radially offset from the radial passages of the disc elements to either side, and said pockets are formed on a plurality of identical pocket members each including a bridge portion spanning the peripheral opening of each radial passage and disposed radially outwardly of the level of the pockets of the pocket members on adjacent disc elements.

Claim 11

A biological wastewater treatment apparatus in accordance with claim 9, wherein each disc element is comprised of identical disc element sectors each including a flat, thin wall, circular sector sheet and a formed, thin wall, circular sector sheet joined to the flat sheet and defining a radial passage and a plurality of concentric passages with said flat sheet and with the flat sheet of an adjacent disc element, and one of said pocket members is joined to the peripheral edge of each flat sector sheet, said bridge portion connecting pockets disposed to each side of the bridge member.

Claim 12

A biological wastewater treatment apparatus, comprising: a treatment tank having a fluid inlet and a fluid outlet, a plurality of flat, uniformly spaced, circular discs mounted on a horizontal shaft and disposed in said tank for partial submergence in the wastewater in the tank, a plurality of cups attached to the perimeter of alternate ones of discs, said cups having a width less than twice the spacing between adjacent discs, and said cups opening outwardly and inclined in one direction from the radius of the disc, a source of air under pressure, and a gas conduit leading from said source of air into said tank, said conduit having a plurality of submerged air openings disposed between the bottom of said tank and each cup carrying disc and beneath open submerged cups.

Claim 13

A biological wastewater treatment apparatus, comprising: a treatment tank having a fluid inlet and a fluid outlet, a plurality of flat, uniformly spaced, circular discs mounted on a horizontal shaft and disposed in said tank for partial submergence in the wastewater in the tank, a plurality of cups attached to the perimeter of alternate ones of discs, said cups having a width less than twice the spacing between adjacent discs, and said cups opening outwardly and inclined in one direction from the radius of the disc, a source of air under pressure, and a gas conduit leading from said source of air into said tank, said conduit having a plurality of submerged air openings disposed between the bottom of said tank and each cup carrying disc and beneath open submerged cups.

Claim 14

A biological wastewater treatment apparatus, comprising: a treatment tank having a fluid inlet and a fluid outlet, an array of thin wall, generally circular formed sheets joined alternately face to face and back to back along a horIzontal shaft and disposed in said tank for partial submergence in the wastewater in said tank, each sheet being formed with walls defining one half of a plurality of radial passages uniformally circumferentially spaced about said sheet and open to the periphery of the sheet, each sheet being also formed with walls defining one half of a plurality of concentric passages extending between adjacent pairs of radial passages and open at each end to a radial passage, a plurality of arcuate elements joined to each pair of sheets, each arcuate element extending along the perimeter of a pair of sheets between each pair of radial openings, said arcuate element each containing a series of cups which are open outwardly and inclined in one direction from the radius of said sheets, said cups having a width equal to the width of a pair of sheets, a source of air under pressure, and a conduit leading from said source of air into said tank and including a plurality of submerged outlets disposed along the length of said tank beneath submerged open cups.

Claim 15

A biological wastewater treatment apparatus, comprising: a treatment tank having a fluid inlet and a fluid outlet, an array of thin wall, generally circular formed sheets joined alternately face to face and back to back along a horIzontal shaft and disposed in said tank for partial submergence in the wastewater in said tank, each sheet being formed with walls defining one half of a plurality of radial passages uniformally circumferentially spaced about said sheet and open to the periphery of the sheet, each sheet being also formed with walls defining one half of a plurality of concentric passages extending between adjacent pairs of radial passages and open at each end to a radial passage, a plurality of arcuate elements joined to each pair of sheets, each arcuate element extending along the perimeter of a pair of sheets between each pair of radial openings, said arcuate element each containing a series of cups which are open outwardly and inclined in one direction from the radius of said sheets, said cups having a width equal to the width of a pair of sheets, a source of air under pressure, and a conduit leading from said source of air into said tank and including a plurality of submerged outlets disposed along the length of said tank beneath submerged open cups.

Claim 16

A biological wastewater treatment apparatus, comprising: a treatment tank having a fluid inlet and a fluid outlet, an array of generally circular sheets juxtaposed along a horizontal shaft and mounted in said tank for partial submergence in the wastewater in said tank, adjacent sheets defining a plurality of circumferentially spaced, radial passages open to the periphery of the sheets, a series of generally concentric discrete passages extending between each pair of radial passages and open at each end to a radial passage, and a plurality of peripheral pockets extending the peripheral openings of said radial passages, said pockets opening outwardly and being inclined in one direction from the radius of said sheet, a source of air under pressure, and a conduit leading from said source of air into said tank and having a plurality of submerged air outlets disposed along the length of said tank and beneath submerged open pockets.

Claim 17

A biological wastewater treatment apparatus, comprising: a treatment tank having a fluid inlet and a fluid outlet, an array of generally circular sheets juxtaposed along a horizontal shaft and mounted in said tank for partial submergence in the wastewater in said tank, adjacent sheets defining a plurality of circumferentially spaced, radial passages open to the periphery of the sheets, a series of generally concentric discrete passages extending between each pair of radial passages and open at each end to a radial passage, and a plurality of peripheral pockets extending the peripheral openings of said radial passages, said pockets opening outwardly and being inclined in one direction from the radius of said sheet, a source of air under pressure, and a conduit leading from said source of air into said tank and having a plurality of submerged air outlets disposed along the length of said tank and beneath submerged open pockets.

Claim 18

A biological wastewater treatment apparatus, comprising: a treatment tank having a fluid inlet and a fluid outlet, a circular rotating biological contactor assembly having a horizontal axis of rotation and adapted for partial submergence in the wastewater in said tank, said contactor assembly including successive layers of disc elements each comprised of a plurality of circular sectors, each circular sector including a flat circular sector sheet and a formed circular sector which together define a radial passage opening to the outer perimeter of the sector and a plurality of concentric interior passages opening to the radial passage and aligned with the concentric passages of adjacent sectors, the radial passages of each layer being angularly offset from the radial passages of adjacent layers, a pocket member attached to each sector and including cup portions having a plurality of cups each opening outwardly in a direction opposite to the direction of rotation of the contactor assembly and a bridge portion disposed at said radial passage and joining the cup portions to each side thereof, said bridge portion being spaced radially outwardly of said cups to provide an opening to said radial passage to either side, a source of air under pressure, and a conduit leading from said source of air into said tank and including a plurality of submerged outlets disposed along the length of said tank beneath submerged open cups.

Claim 19

A biological wastewater treatment apparatus, comprising: a treatment tank having a fluid inlet and a fluid outlet, a circular rotating biological contactor assembly having a horizontal axis of rotation and adapted for partial submergence in the wastewater in said tank, said contactor assembly including successive layers of disc elements each comprised of a plurality of circular sectors, each circular sector including a flat circular sector sheet and a formed circular sector which together define a radial passage opening to the outer perimeter of the sector and a plurality of concentric interior passages opening to the radial passage and aligned with the concentric passages of adjacent sectors, the radial passages of each layer being angularly offset from the radial passages of adjacent layers, a pocket member attached to each sector and including cup portions having a plurality of cups each opening outwardly in a direction opposite to the direction of rotation of the contactor assembly and a bridge portion disposed at said radial passage and joining the cup portions to each side thereof, said bridge portion being spaced radially outwardly of said cups to provide an opening to said radial passage to either side, a source of air under pressure, and a conduit leading from said source of air into said tank and including a plurality of submerged outlets disposed along the length of said tank beneath submerged open cups.