Sewage sludge and garbage grinder

Claim 2

Grinding apparatus comprising a motor driven shaft, a housing therefor, an outlet for the housing, an impeller and grid-plate on the shaft, an inlet for the housing facing the impeller, and a cutter on the housing, said cutter having a pair of shearing surfaces at an angle to each other, one of said surfaces cooperating with the impeller at the upstream side of the flow of sludge from the inlet to reduce particles in the sludge, the other cutter surface cooperating with the peripheral edge area of the grid-plate, further reducing sludge particles downstream of the flow as regards the impeller.

Claim 3

Grinding apparatus of claim 1 wherein the cutter is located at the periphery of the impeller and grid-plate.

Claim 4

Grinding apparatus of claim 1 wherein the cutter is located at the periphery of the impeller and grid-plate and the impeller includes radial arms tending to force the sludge outwardly radially toward the cutter.

Claim 5

The grinding apparatus of claim 1 wherein said impeller tends to move the sludge radially outwardly, said grid-plate being provided with peripheral slots for passing the sludge.

Claim 6

The grinding apparatus of claim 1 wherein said impeller tends to move the sludge radially outwardly, said grid-plate being provided with peripheral slots for passing the sludge and said cooperative grinding with respect to the respective shearing surface of said cutter.

Claim 7

The grinding apparatus of claim 1 wherein said impeller tends to move the sludge radially outwardly, said grid-plate being provided with peripheral slots for passing the sludge, said slots being inclined with respect to the axis of said shaft and of said grid-plate and passing completely through the grid-plate.

Claim 8

Grinding apparatus of claim 1 including means exterior of said housing for mounting said cutter.

Claim 9

Grinding apparatus of claim 1 including means exterior of said housing for mounting said cutter, and means for adjusting said cutter.

Claim 10

Grinding apparatus of claim 1 including means exterior of said housing for mounting said cutter, and for removing and replacing the same from outside the housing.

Claim 11

Grinding apparatus for sludge comprising a housiNg forming a chamber, a shaft in said housing within the chamber, an inlet for the sludge, a rotary impeller and grid-plate assembly mounted on said shaft, a plurality of generally radially arranged circumferentially spaced cutters mounted on said housing and projecting inwardly thereof, each cutter having a pair of surfaces at angles to each other, the impeller including radial arms tending to force the sludge radially outwardly toward the cutters, respective surfaces of each cutter cooperating with the peripheral edge of said impeller arms providing a shearing and grinding action therewith, the grid-plate having a series of slots therein at the edge thereof, the slots extending through the plate, and the other respective surfaces of the cutters having a shearing and grinding cooperation with respect to the forward face of the grid-plate in the region of said slots, and an outlet, the ground sludge passing through the slots to the outlet.

Claim 12

Grinding apparatus for sludge comprising a housiNg forming a chamber, a shaft in said housing within the chamber, an inlet for the sludge, a rotary impeller and grid-plate assembly mounted on said shaft, a plurality of generally radially arranged circumferentially spaced cutters mounted on said housing and projecting inwardly thereof, each cutter having a pair of surfaces at angles to each other, the impeller including radial arms tending to force the sludge radially outwardly toward the cutters, respective surfaces of each cutter cooperating with the peripheral edge of said impeller arms providing a shearing and grinding action therewith, the grid-plate having a series of slots therein at the edge thereof, the slots extending through the plate, and the other respective surfaces of the cutters having a shearing and grinding cooperation with respect to the forward face of the grid-plate in the region of said slots, and an outlet, the ground sludge passing through the slots to the outlet.

Claim 13

The grinding apparatus of claim 10 wherein the slots are inclined relative to the axis of the shaft and grid-plate.

Claim 14

The grinding apparatus of claim 10 wherein the shaft is generally vertical and the inlet is at the bottom of the chamber, the impeller being above the inlet so that heavy objects fail to engage the impeller.