US3861903A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Upgrading of chromite and other ferruginous ores
Assignee: Crucible SA
•
Filing: 1972-08-07
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Granted: 1975-01-21
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Expires: 1992-08-07
Abstract
Abstract Prereduced ferruginous ores of chromite, ilmenite and phosphate minerals are upgraded in a single stage process utilising ferrous sulphate or ferrous chloride leach solutions. While leaching takes place air or oxygen is blown in so as to reduce ferric salts to the ferrous state with the precipitation of hydrated iron oxides. The process is conducted at a temperature of between 55* and 60*C. The upgraded ore and iron hydrate are subsequently separated by means of cyclones, elutriation, tabling, flotation and so on.
Inventors
- 👤 Thomas Joseph Coyle
- 👤 Herbert Joseph Bovey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:38
CPC Classifications
C; C22; C22B; C22B3/00; C22B3/04; C22B3/06; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
161 words
A METHOD OF UPGRADING AN ORE SELECTED FROM THE GROUP CONSISTING OF CHROMITE, ILMENITE AND PHOSPHATE WHICH IS RENDERED LOWGRADE BY THE PRESENCE OF IRON OXIDE AND WHICH ORE HAS BEEN ROASTED TO REDUCE THE IRON OXIDE TO THE METALLIC STATE CONSISTING IN THE STEPS OF INTIMATELY ADMIXING A MIXTURE OF THE ROASTED ORE AND AN IRON SALT SOLUTION, SELECTED FROM FERROUS SULPHATE AND FERROUS CHLORIDE SOLUTIONS, WITH A GAS CONTAINING FREE OXYGEN, AT ABOUT AMBIEN PRESSURE, WITH THE RESULT THAT THE IRON IN ROASTED ORE REDUCES FERRIC SALTS IN SOLUTIONS TO THE FERROUS STATE WHILE SIMULTANEOUSLY OXYGEN IN THE GAS OXIDIZES FERROUS SALTS TO THE FERRIC STATE SO THAT METALLIC IRON IS LEACH ED FROM THE ROASTED ORE TO LEAVE INSOLUBLE RESIDUAL ORE PARTICLES AND TO FORM INSOLUBLE HYDRATED IRON OXIDE, AND SEPARATING THE RESIDUAL ORE PARTICLES FROM THE SOLUTION AND THE HYDRATED IRON OXIDE TO PROVIDE AN ORE PRODUCT WHICH IS LESS DILUTED BY THE PRESENCE OF IRON OXIDE.
Claim 2
Independent Claim
161 words
A METHOD OF UPGRADING AN ORE SELECTED FROM THE GROUP CONSISTING OF CHROMITE, ILMENITE AND PHOSPHATE WHICH IS RENDERED LOWGRADE BY THE PRESENCE OF IRON OXIDE AND WHICH ORE HAS BEEN ROASTED TO REDUCE THE IRON OXIDE TO THE METALLIC STATE CONSISTING IN THE STEPS OF INTIMATELY ADMIXING A MIXTURE OF THE ROASTED ORE AND AN IRON SALT SOLUTION, SELECTED FROM FERROUS SULPHATE AND FERROUS CHLORIDE SOLUTIONS, WITH A GAS CONTAINING FREE OXYGEN, AT ABOUT AMBIEN PRESSURE, WITH THE RESULT THAT THE IRON IN ROASTED ORE REDUCES FERRIC SALTS IN SOLUTIONS TO THE FERROUS STATE WHILE SIMULTANEOUSLY OXYGEN IN THE GAS OXIDIZES FERROUS SALTS TO THE FERRIC STATE SO THAT METALLIC IRON IS LEACH ED FROM THE ROASTED ORE TO LEAVE INSOLUBLE RESIDUAL ORE PARTICLES AND TO FORM INSOLUBLE HYDRATED IRON OXIDE, AND SEPARATING THE RESIDUAL ORE PARTICLES FROM THE SOLUTION AND THE HYDRATED IRON OXIDE TO PROVIDE AN ORE PRODUCT WHICH IS LESS DILUTED BY THE PRESENCE OF IRON OXIDE.
Claim 3
Dependent Claim
33 words
The method claimed in claim 1 in which the ore is a chromite ore that has been so prereduced that a substantial proportion of the iron present is in an acid soluble form.
Claim 4
Dependent Claim
33 words
The method claimed in claim 1 in which the ore is an ilmenite ore which has been so prereduced that a substantial proportion of the iron present is in an acid soluble form.
Claim 5
Dependent Claim
33 words
The method claimed in claim 1 in which the ore is a phosphate ore which has been so prereduced that a substantial proportion of the iron present is in an acid soluble form.
Claim 6
Dependent Claim
14 words
The method claimed in claim 1 in which the iron salt is ferrous sulphate.
Claim 7
Dependent Claim
14 words
The method claimed in claim 1 in which the iron salt is ferrous chloride.
Claim 8
Dependent Claim
12 words
The method claimed in claim 1 in which the gas is air.
Claim 9
Dependent Claim
12 words
The method claimed in claim 1 in which the gas is oxygen.
Claim 10
Dependent Claim
18 words
The method claimed in claim 1 in which leaching is carried out at a temperature of above 40*C.
Claim 11
Dependent Claim
20 words
The method claimed in claim 1 in which leaching is carried out at a temperature of between 55*C and 75*C.
Claim 12
Dependent Claim
20 words
The method claimed in claim 1 in which leaching is carried out at a temperature of between 55* and 60*C.
References Cited (Backward Citations)
US981451A
Cited
US1129407A
Cited
US1327061A
Cited
US3105755A
Cited
US3169853A
Cited
US3252787A
Cited
US3681047A
Cited
US3684485A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-20 | 1978-07-22 | 1979-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-20 | 1982-07-22 | 1983-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-20 | 1986-07-22 | 1987-01-21 | $7700.00 | Window Closed / Lapsed |