US4718559A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for recovery of non-ferrous metallic concentrate from solid waste
Assignee: Magnetic Separation Systems Inc
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Filing: 1985-07-02
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Granted: 1988-01-12
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Expires: 2005-07-02
Abstract
Abstract Selective non-magentic detection of non-ferrous metallic particles in a mixture of same with ferrous metallic particles and non-metallic particles derived from homogenized and magnetically treated municipal or like waste by a plurality of electronic detectors and separation of a non-ferrous metallic concentrate from said mixture.
Inventors
- 👤 Garry R. Kenny
- 👤 Edward J. Sommer, Jr.
- 👤 Mark E. Shepard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:06
CPC Classifications
C; C22; C22B; C22B7/00; C22B7/005; B; B03; B03B; B03B9/00; B03B9/06; B03B9/061; B07; B07C; B07C5/00; B07C5/34; B07C5/344; B07C5/36; B07C5/363; B07C5/365; B07C5/366; B07C2501/00; B07C2501/0036; Y; Y02; Y02P; Y02P10/00; Y02P10/20; Y02W; Y02W30/00; Y02W30/50; Y02W30/52
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
138 words
A non-magnetic process for the separation of non-ferrous metallic particles from a solid waste mixture of non--metallic particles, ferrous metallic particles and non-ferrous metallic particles, comprising the steps of: (a) conducting a solid waste mixture of non-metallic particles, ferrous metallic particles, and non-ferrous metallic particles in a feed stream through a concentration zone, (b) electronically detecting said non-ferrous metallic particles in said concentration zone by passing all said particles in the vicinity of a detector coil connected in a phase detector circuit, said circuit producing a frequency phase error signal comparable to a decrease in the inductance of said detector coil responsive only to the proximity of said non-ferrous metallic particles, (c) removing said non-ferrous metallic particles from said ferrous metallic particles and said non-metallic particles in said feed stream in response to said frequency phase error signal.
Claim 2
Dependent Claim
138 words
A non-magnetic process for the separation of non-ferrous metallic particles from a solid waste mixture of non--metallic particles, ferrous metallic particles and non-ferrous metallic particles, comprising the steps of: (a) conducting a solid waste mixture of non-metallic particles, ferrous metallic particles, and non-ferrous metallic particles in a feed stream through a concentration zone, (b) electronically detecting said non-ferrous metallic particles in said concentration zone by passing all said particles in the vicinity of a detector coil connected in a phase detector circuit, said circuit producing a frequency phase error signal comparable to a decrease in the inductance of said detector coil responsive only to the proximity of said non-ferrous metallic particles, (c) removing said non-ferrous metallic particles from said ferrous metallic particles and said non-metallic particles in said feed stream in response to said frequency phase error signal.
Claim 3
Dependent Claim
35 words
The invention according to claim 1 further comprising the step of high-pass filtering said error signal so that said error signal is free of low frequencies generated by thermal drift of said phase detector circuit.
Claim 4
Dependent Claim
46 words
The process according to claim 1 in which said removing step comprises producing air pulses to project said non-ferrous metallic particles detected in said concentration zone in response to said error signal away from the other particles in said solid waste mixture in said feed stream.
Claim 5
Dependent Claim
41 words
The process according to claim 3 further comprising the step of delaying the producing of said air pulses after the production of said frequency phase error signal until the detected non-ferrous metallic particles are in the path of said air pulses.
Claim 6
Dependent Claim
22 words
The process according to claim 4 further comprising the step of high-pass filtering said error signal generated by said phase detector circuit.
Claim 7
Dependent Claim
26 words
The process according to claim 1 in which said phase detector circuit is a closed loop circuit including said detector coil and a phase lock loop.
Claim 8
Dependent Claim
38 words
The process according to claim 1 in which said removing step comprises projecting said non-ferrous metallic particles detected in said concentration zone in response to said error signal away from said feed stream of said solid waste mixture.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-01-11 | 1991-07-13 | 1992-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-01-11 | 1995-07-13 | 1996-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-01-11 | 1999-07-13 | 2000-01-12 | $7700.00 | Window Closed / Lapsed |