US3625354A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for magnetically separating reduced iron-containing materials discharged from a rotary kiln
Assignee: Steel Company of Canada Ltd
•
Filing: 1969-01-21
•
Granted: 1971-12-07
•
Expires: 1989-01-21
Abstract
Abstract Iron-containing materials reduced in a rotary kiln are separated magnetically into a high iron-containing fraction and a low-ash reducing agent fraction in two stages, one above and one below 1,000 oersteds. The reducing agent fraction which is recycled to the kiln, keeps the ash content of the recycled reducing agent substantially constant.
Inventors
- 👤 Gunter Heitmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 05:26
CPC Classifications
C; C07; C07C; C07C251/00; C07C251/72; B; B03; B03C; B03C1/00; C21; C21B; C21B13/00; C21B13/0086; C21B13/08; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
18 words
A process as in claim 1, further comprising separating the below 1-mm. fraction in a similar two-stage process.
Claim 2
Dependent Claim
32 words
A process as in claim 1 in which a first stage separation is operated at a high field strength above 1,000 oersteds, and a second stage separation is operated below 1,000 oersteds.
Claim 3
Dependent Claim
32 words
A process as in claim 1, in which a first stage separation is operated at a low field strength below 1,000 oersteds, and a second stage separation is operated above 1,000 oersteds.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-06 | 1975-06-07 | 1975-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-06 | 1979-06-07 | 1979-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-06 | 1983-06-07 | 1983-12-07 | $7700.00 | Window Closed / Lapsed |