# US 4,397,713 A · Method of processing waste paper and installation for the performance of the method

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- Number: US 4,397,713 A
- Document ID: US4397713A
- Status: Granted
- Kind: A
- Application number: 06/197,117
- Filed: 1980-10-15
- Granted: 1983-08-09
- Earliest claimed: 1979-11-15
- Assignees: Escher Wyss Limited
- Inventors: Gerhard Lambrecht
- Web page: https://patentgrep.com/patent/US4397713A

## CPC

- D21B 1/32: of waste paper
- Y02W 30/64: Paper recycling
- D21B: FIBROUS RAW MATERIALS OR THEIR MECHANICAL TREATMENT
- Y02W: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT

## Abstract

A method of preparing waste paper wherein the waste paper is defiberized in water within a stock slusher or pulper. Following the stock pulper there is removed from the stock suspension all of the already available good stock fibres by means of a sieve or screen device. The remainder of the stock suspension is then subjected to a comminution action and is again screened. The screening and comminution can take place in a first fiberizer or secondary pulper having a finer sieve or screen than a conventional secondary pulper. The overflow of the first secondary pulper is infed to a second secondary pulper and the overflow thereof is then fed to a dynamic jarrer or vibrator. Forwardly of the dynamic jarrer there is arranged a vat containing a circulation system of a despeckling device.

## Claims

### Claim 1

An apparatus for preparing waste paper for obtaining stock suspension for the fabrication of new paper and cardboard, comprising:
a stock slusher through which passes waste paper;
at least one fiberizer arranged after and cooperating with the stock slusher;
said at least one fiberizer containing a housing; a screen and a motor-driven rotor arranged within said housing;
said rotor having arm means movable along said screen;
outlet means through which flows good stock which has passed through the screen arranged in flow communication with said screen;
said housing having at least one outlet for overflow material effluxing from said housing;
said screen of said at least one fiberizer containing perforations of a size suitable for separating fibers which can be directly used for paper fabrication;
a vat of a papermaking machine connected in flow communication with the outlet means for the good stock of said at least one fiberizer;
said at least one fiberizer contains an outlet line for lighter overflow material;
a dynamic vibrator with which there is operatively connected said outlet line for the lighter overflow material of said at least one fiberizer;
a vat means located at the outlet line for the lighter overflow material of said at least one fiberizer and flow communicating said outlet line with said dynamic vibrator;
circulation flow means provided for said vat means;
a despeckling device arranged in said circulation flow means of said vat means; and
a throughflow container provided for the dynamic vibrator; and
said throughflow container being connected with said vat of the papermaking machine.

### Claim 2

An apparatus for preparing waste paper for obtaining stock suspension for the fabrication of new paper and cardboard, comprising:
a stock slusher through which passes waste paper;
a first fiberizer arranged after and cooperating with the stock slusher;
said first fiberizer containing a housing;
a screen and a motor-driven rotor arranged within said housing;
said rotor having arm means movable along said screen;
outlet means through which flows good stock which has passed through the screen arranged in flow communication with said screen;
said housing having at least one outlet for overflow material effluxing from said housing;
said screen of said first fiberizer containing perforations of a size suitable for separating fibers which can be directly used for paper fabrication;
a vat of a papermaking machine connected in flow communication with the outlet means for the good stock of the first fiberizer;
a second fiberizer connected with the at least one outlet for the overflow material of the first fiberizer;
said second fiberizer containing a screen having perforations of a size suitable for screening essentially all fibers which can be directly used for paper fabrication;
said second fiberizer having outlet means for good stock which has passed through the screen of said second fiberizer;
said outlet means of said second fiberizer being connected in flow communication with said vat of the papermaking machine;
the perforations of the screen of the first fiberizer containing holes having a diameter in a range of approximately 2 to 3 millimeters;
said second fiberizer contains an outlet line for lighter overflow material;
a dynamic vibrator with which there is connected said outlet line for the lighter overflow material of the second fiberizer;
a vat located at the outlet line for the lighter overflow material of the second fiberizer;
circulation flow means provided for said vat; and
a despeckling device arranged in said circulation flow means of said vat.

### Claim 3 (depends on 2)

The apparatus as defined in claim 2, wherein:
the perforations of the screen of the second fiberizer contain holes having a diameter in a range of approximately 2 to 3 millimeters.

### Claim 4 (depends on 2)

The apparatus as defined in claim 2, further including:
a throughflow container provided for the dynamic vibrator; and
said throughflow container being connected with said vat of the papermaking machine.