US4570861A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and arrangement for electrostatic separation of paper- and synthetic plastic material-containing mixtures
Assignee: K+S AG
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Filing: 1983-07-25
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Granted: 1986-02-18
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Expires: 2003-07-25
Abstract
Abstract An elecrtrostatic separation of paper- and synthetic plastic material-containing mixtures is performed by comminuting the mixture, triboelectrically charging the comminuted mixture, and supplying it into a free-fall separator, wherein a paper-enriched and a synthetic plastic material-enriched fraction are produced, and in some cases they can be treated in a second electrostatic separation step to pure products.
Inventors
- 👤 Helmut Zentgraf
- 👤 Gunter Fricke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:21
CPC Classifications
B; B29; B29B; B29B17/00; B29B17/02; B03; B03B; B03B9/00; B03B9/06; B03B9/061; B03C; B03C7/00; B03C7/02; B03C7/12; D; D21; D21B; D21B1/00; D21B1/02; D21B1/026; D21B1/028; D21C; D21C5/00; D21C5/02; B29B2017/0213; B29B2017/0262; B29B2017/0265; B29K; B29K2711/00; B29K2711/12; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/52; Y02W30/62; Y02W30/64; Y10; Y10S; Y10S241/00; Y10S241/38
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
152 words
A method of electrostatically separating paper- and synthetic plastic-containing mixtures, comprising the steps of comminuting a paper- and synthetic plastic-containing mixture into particles with a width of substantially 3-4 mm and a length of substantially 10-20 mm; triboelectrically charging the particles in an atmosphere with a relative moisture of between 5 and 20% at a temperature of between 25° and 80° C.; feeding the triboelectrically charged particles into a free-fall separator with an electrostatic field of between 1 and 4 kV/cm, so that the triboelectrically charged particles fall freely through the separator and under the action of the electrostatic field are deflected so that at a bottom of the separator a paper-enriched fraction is collected in the vicinity of a positive electrode, a synthetic plastic-enriched fraction is collected in the vicinity of a negative electrode, and an intermediate fraction is collected therebetween; and supplying the intermediate fraction back into the free-fall separator.
Claim 2
Independent Claim
152 words
A method of electrostatically separating paper- and synthetic plastic-containing mixtures, comprising the steps of comminuting a paper- and synthetic plastic-containing mixture into particles with a width of substantially 3-4 mm and a length of substantially 10-20 mm; triboelectrically charging the particles in an atmosphere with a relative moisture of between 5 and 20% at a temperature of between 25° and 80° C.; feeding the triboelectrically charged particles into a free-fall separator with an electrostatic field of between 1 and 4 kV/cm, so that the triboelectrically charged particles fall freely through the separator and under the action of the electrostatic field are deflected so that at a bottom of the separator a paper-enriched fraction is collected in the vicinity of a positive electrode, a synthetic plastic-enriched fraction is collected in the vicinity of a negative electrode, and an intermediate fraction is collected therebetween; and supplying the intermediate fraction back into the free-fall separator.
Claim 3
Dependent Claim
21 words
A method as defined in claim 1, wherein said comminuting step includes comminuting the paper- and synthetic plastic-containing mixture into stripes.
Claim 4
Dependent Claim
21 words
A method as defined in claim 1, wherein said comminuting step includes comminuting the paper- and synthetic plastic-containing mixture into chips.
Claim 5
Dependent Claim
41 words
A method as defined in claim 1; and further comprising the step of separating the enriched fractions in a second stage of the free-fall cutter so as to produce a practically pure paper-containing fraction and a practically pure synthetic plastic containing-fraction.
Claim 6
Dependent Claim
156 words
An arrangement for electrostatically separating paper- and synthetic plastic-containing mixtures, comprising means for comminuting a paper- and synthetic plastic-containing mixture into particles with a width of substantially 3-4 mm and a length of substantially 10 -20 mm; means for triboelectrically charging the particles in an atmosphere with a relative moisture of between 5 and 20% with a temperature of between 25° and 80° C.; a free-fall separator with an electrostatic field of between 1 and 4 kV/cm for feeding the triboelectrically charged particles so that the triboelectrically charged particles fall freely through the separator and under the action of the electrostatic field are deflected so that at a bottom of the separator a paper-enriched fraction is collected in the vicinity of a positive electrode, a synthetic plastic-enriched fraction is collected in the vicinity of a negative electrode, and an intermediate fraction is collected therebetween; and means for supplying the intermediate fraction back into the free-fall separator.
Claim 7
Dependent Claim
156 words
An arrangement for electrostatically separating paper- and synthetic plastic-containing mixtures, comprising means for comminuting a paper- and synthetic plastic-containing mixture into particles with a width of substantially 3-4 mm and a length of substantially 10 -20 mm; means for triboelectrically charging the particles in an atmosphere with a relative moisture of between 5 and 20% with a temperature of between 25° and 80° C.; a free-fall separator with an electrostatic field of between 1 and 4 kV/cm for feeding the triboelectrically charged particles so that the triboelectrically charged particles fall freely through the separator and under the action of the electrostatic field are deflected so that at a bottom of the separator a paper-enriched fraction is collected in the vicinity of a positive electrode, a synthetic plastic-enriched fraction is collected in the vicinity of a negative electrode, and an intermediate fraction is collected therebetween; and means for supplying the intermediate fraction back into the free-fall separator.
References Cited (Backward Citations)
US3856217A
Cited
US4092241A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-02-17 | 1989-08-19 | 1990-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-02-17 | 1993-08-19 | 1994-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-02-17 | 1997-08-19 | 1998-02-18 | $7700.00 | Window Closed / Lapsed |