US3821026A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Scrap metal recovery method and apparatus
Assignee: Individual
•
Filing: 1973-01-05
•
Granted: 1974-06-28
•
Expires: 1993-01-05
Abstract
Abstract Plastic coated scrap metal heated within a vented combustion chamber to cause decomposition of the plastic without adversely affecting the metal core with respect to its subsequent separation from the decomposed plastic and recovery as a substantially pure metal product. A fuel gas mixture is fed at a controlled rate to the combustion chamber to initially elevate the temperature of the chamber to an optimum value that is then maintained constant. The products of combustion form a nonoxidizing atmosphere in the chamber within which the desired decomposition of the plastic occurs.
Inventors
- 👤 E Swartz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:05
CPC Classifications
C; C22; C22B; C22B7/00; C22B7/001; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
13 words
The method of claim 1 wherein said optimum temperature is approximately 800* F.
Claim 2
Dependent Claim
18 words
The method of claim 1 wherein said metallic core is copper and the coating is a polyethylene plastic.
Claim 3
Dependent Claim
35 words
The method of claim 1 wherein said gaseous fuel is a mixture of natural gas and air at a selected ratio resulting in said predetermined concentration of combustion and decomposition products in the treating zone.
Claim 4
Dependent Claim
13 words
The method of claim 4 wherein said optimum temperature is approximately 800* F.
Claim 5
Dependent Claim
19 words
The method of claim 5 wherein said scrap material is copper wire and the coating is a polyethylene insulation.
Claim 6
Dependent Claim
138 words
In a method treating scrap material having a metallic core and a decomposable, non-metallic coating, to facilitate removal of the coating and recovery of a substantially pure metallic product, the steps of: placing the scrap material in a confined treating zone; generating heat within the treating zone by combustion of a gaseous fuel supplied thereto at a substantially constant flow rate until the decomposition of the coating begins; and then varying the flow rate of the gaseous fuel as a function of heat release by decomposition to maintain a substantially constant temperature within the treating zone; and including the step of venting the treating zone during combustion to maintain a predetermined concentration of combustion and decomposition products forming a non-oxidizing atmosphere within the treating zone at said substantially constant temperature below the melting point of the metallic core.
Claim 7
Dependent Claim
24 words
The method of claim 7 wherein the scrap material is exposed to the heat within the treating zone while in a substantially stationary condition.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |