US4597790A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing unbaked agglomerates
Assignee: JFE Engineering Corp
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Filing: 1985-05-21
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Granted: 1986-07-01
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Expires: 2005-05-21
Abstract
Abstract In a method of producing unbaked agglomerates, green pellets or briquettes are produced by adding 5 to 30% of reduced iron powder, mill scale powder or iron sand and also adding a binder consisting of a cement or granulated blast furnace slag and then the green pellets or briquettes are dry cured thereby producing agglomerates having excellent reducing performance.
Inventors
- 👤 Seiji Matsui
- 👤 Kazuharu Yatsunami
- 👤 Tsuneo Miyashita
- 👤 Noboru Sakamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 05:59
CPC Classifications
C; C22; C22B; C22B1/00; C22B1/14; C22B1/24; C22B1/242; C22B1/243; C22B1/2413
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
123 words
A method of producing unbaked agglomerates in the form of cold bonded pellets or briquettes comprising the steps of: adding a binder to an iron oxide-type raw material containing iron ore fines, baked pellet undersized powder or dust powder originating from iron works, producing green pellets or briquettes from said binder-added raw material, and drying and curing said green pellets or briquettes, wherein at least one selected from the group consisting of reduced iron powder containing 10 wt. percent or more of metal iron, mill scale powder containing 20 wt. percent or more of FeO, or iron sand containing 20 wt. percent or more of FeO is compounded to said raw material in an amount of 5-30 wt. percent of said raw material.
Claim 2
Independent Claim
123 words
A method of producing unbaked agglomerates in the form of cold bonded pellets or briquettes comprising the steps of: adding a binder to an iron oxide-type raw material containing iron ore fines, baked pellet undersized powder or dust powder originating from iron works, producing green pellets or briquettes from said binder-added raw material, and drying and curing said green pellets or briquettes, wherein at least one selected from the group consisting of reduced iron powder containing 10 wt. percent or more of metal iron, mill scale powder containing 20 wt. percent or more of FeO, or iron sand containing 20 wt. percent or more of FeO is compounded to said raw material in an amount of 5-30 wt. percent of said raw material.
Claim 3
Dependent Claim
22 words
A method of producing unbaked agglomerates according to claim 1 wherein cement or granulated blast furnace slag is added as the binder.
Claim 4
Dependent Claim
24 words
A method of producing unbaked agglomerates according to claim 1 wherein said drying and curing step comprises pre-drying, then steam curing, and then post-drying.
Claim 5
Dependent Claim
27 words
A method of producing unbaked agglomerates according to claim 1 wherein said green pellets or briquettes are cured in an atmosphere containing carbon dioxide gas and steam.
Claim 6
Independent Claim
106 words
A method for continuously producing unbaked agglomerates in the form of cold bonded pellets or briquettes, comprising the steps of compounding reduced iron powder containing 10 wt. percent or more of metal iron in an amount of 5-30 wt. percent of an iron oxide-type raw material containing iron ore fines, baked pellet undersized powder or dust powder originating from iron works to said raw material; adding a binder to the foregoing compound; producing green pellets or briquettes from said binder-added raw material; pre-drying said green pellets or briquettes; curing said green pellets or briquettes in an atmosphere containing steam; and post-drying said green pellets or briquettes.
Claim 7
Independent Claim
106 words
A method for continuously producing unbaked agglomerates in the form of cold bonded pellets or briquettes, comprising the steps of compounding reduced iron powder containing 10 wt. percent or more of metal iron in an amount of 5-30 wt. percent of an iron oxide-type raw material containing iron ore fines, baked pellet undersized powder or dust powder originating from iron works to said raw material; adding a binder to the foregoing compound; producing green pellets or briquettes from said binder-added raw material; pre-drying said green pellets or briquettes; curing said green pellets or briquettes in an atmosphere containing steam; and post-drying said green pellets or briquettes.
Claim 8
Dependent Claim
20 words
A method of producing unbaked agglomerates according to claim 5, wherein said binder includes cement or granulated blast furnace slag.
Claim 9
Independent Claim
98 words
A method of continuously producing unbaked agglomerates in the form of cold bonded pellets or briquettes, comprising the steps of compounding reduced iron powder containing 10 wt. percent or more of metal iron in an amount of 5-30 wt. percent of an iron oxide-type raw material containing iron ore fines, baked pellet undersized powder or dust powder originating from iron works to said raw material; adding a binder to the foregoing compound; producing green pellets or briquettes from said binder-added raw material; and curing said green pellets or briquettes in an atmosphere containing carbon dioxide gas and steam.
Claim 10
Independent Claim
98 words
A method of continuously producing unbaked agglomerates in the form of cold bonded pellets or briquettes, comprising the steps of compounding reduced iron powder containing 10 wt. percent or more of metal iron in an amount of 5-30 wt. percent of an iron oxide-type raw material containing iron ore fines, baked pellet undersized powder or dust powder originating from iron works to said raw material; adding a binder to the foregoing compound; producing green pellets or briquettes from said binder-added raw material; and curing said green pellets or briquettes in an atmosphere containing carbon dioxide gas and steam.
Claim 11
Dependent Claim
20 words
A method of producing unbaked agglomerates according to claim 7 wherein said binder includes cement or granulated blast furnace slag.
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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) | 1989-06-30 | 1989-12-30 | 1990-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-30 | 1993-12-30 | 1994-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-30 | 1997-12-30 | 1998-07-01 | $7700.00 | Window Closed / Lapsed |