Air-classification apparatus and process for the segregation of mixed office-paper waste

Claim 2

A process for the segregation and separation of mixed office-paper-waste material, which process comprises: (a) shredding the waste material into waste material of substantially uniform size; (b) introducing the shredded waste material into a vertically disposed fractionating column; (c) passing high-volume, low-pressure air upwardly through the column to form a fluidized bed within the column of the shredded waste material, the bed containing at least one discrete segregated layer of the segregated shredded waste material; (d) removing the segregated waste material from the discrete layer by flowing high-pressure low-volume air to cause lateral flow of the segregated waste material across the discrete layer to a discharge outlet in the column; and (e) recovering the removed segregated waste material.

Claim 3

The process of claim 1 which includes shredding the waste material into a uniform size and dimension of 1/4 to 2 inches in dimension.

Claim 4

The process of claim 1 wherein the office-paper-waste material comprises about 0 to 15% by weight of contaminants, 0 to 15% by weight of coffee cups and heavy waste paper, and the remainder waste writing and newspaper material.

Claim 5

The process of claim 1 wherein the high-volume, low-pressure air comprises about 30 to 60 cfm per pound of waste material at a pressure of about 5 to 50 psig.

Claim 6

The process of claim 1 which includes introducing the shredded waste material into the lower portion of the fractionating column, and removing a heavy fraction of the waste material from the bottom of the column.

Claim 7

The process of claim 1 wherein the top discrete layer comprises contaminant material and the lower layer comprises writing paper and newsprint.

Claim 8

The process of claim 1 wherein the recovered waste material is segregated and separated by repeating the steps of claim 1.

Claim 9

The process of claim 1 which includes recovering the segregated waste material by passing the removed mixture into an air-solid cyclone separator, and recycling the air from the cyclone for use in the column.

Claim 10

The process of claim 1 which includes removing the segregated waste material from the discrete layer by an eductor means in the discharge outlet to move the waste material into the discharge outlet.

Claim 11

A process for the segregation and separation of a medium fraction composed of writing paper and newsprint-type paper from mixed office-paper waste containing a light contaminant fraction and a heavy paper-board fraction, which process comprises: (a) shredding the waste material into waste material of a substantially uniform size and dimension of 1/4 to 2 inches in dimension; (b) introducing the shredded waste material into a vertically disposed fractionating column; (c) passing high-volume, low-pressure air upwardly through the column to form a fluidized bed within the column of the shredded waste material, the bed containing at least one discrete segregated layer of the segregated shredded waste material; (d) removing the segregated waste material from the discrete layer by flowing high-pressure low-volume air to cause lateral flow of the segregated waste material across the discrete layer to a discharge outlet in the column; and (e) a recovering the removed segregated waste material.

Claim 12

A process for the segregation and separation of a medium fraction composed of writing paper and newsprint-type paper from mixed office-paper waste containing a light contaminant fraction and a heavy paper-board fraction, which process comprises: (a) shredding the waste material into waste material of a substantially uniform size and dimension of 1/4 to 2 inches in dimension; (b) introducing the shredded waste material into a vertically disposed fractionating column; (c) passing high-volume, low-pressure air upwardly through the column to form a fluidized bed within the column of the shredded waste material, the bed containing at least one discrete segregated layer of the segregated shredded waste material; (d) removing the segregated waste material from the discrete layer by flowing high-pressure low-volume air to cause lateral flow of the segregated waste material across the discrete layer to a discharge outlet in the column; and (e) a recovering the removed segregated waste material.