US3739549A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rhenium extraction process
Assignee: Individual
•
Filing: 1971-10-28
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Granted: 1973-06-19
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Expires: 1991-10-28
Abstract
Abstract The recovery of rhenium from roaster gases is improved in extraction efficiency in that, following the removal of solids from the gas, the dust-cleaned gaseous effluent remaining which contains particles of rhenium oxide ranging down to submicron size is then subjected to wet-filtering, whereby to effect a substantial improvement in the recovery of rhenium in the gas.
Inventors
- 👤 R Hevia
- 👤 Krebs L Soto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:03
CPC Classifications
B; B01; B01D; B01D47/00; B01D47/06; C; C01; C01G; C01G47/00
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
74 words
The method of claim 1, wherein the wet-filtering comprises a first filtering step and at least a second wet-filtering step in series therewith, wherein the filtered gaseous effluent from the first filtering step is fed to the second wet-filtering step, the rhenium-containing liquor accumulated at each step being recycled to the wet filter, whereby to upgrade the rhenium concentration in the liquor, the liquor accumulated in each step being thereafter combined for rhenium extraction.
Claim 2
Dependent Claim
23 words
The method of claim 2, wherein rhenium-containing liquor obtained from at least the second filtering step is recycled to the first filtering step.
Claim 3
Dependent Claim
26 words
The method of claim 1, in which the wet-filtering phase includes passage of a flow of a dust-cleaned gaseous effluent through a water-wetted thin fibrous screen.
Claim 4
Independent Claim
143 words
The method of recovering rhenium from rhenium-containing roaster gas which comprises: dust-cleaning said gas to separate solid component therefrom and thereby produce a dust-clean gaseous effluent, wet-scrubbing with water the gaseous effluent to product a first rhenium-bearing liquor, thereby discharging a wet-scrubbed gaseous effluent containing submicron rhenium oxide particles, accumulating a predetermined supply of said first rhenium-bearing liquor and recycling said supply in the wet-scrubbing phase to upgrade the rhenium concentration in said first liquor, wet-filtering with water the wet-scrubbed gaseous effluent, whereby a second rhenium-bearing liquor is obtained, adding the second liquor to the recycling supply of the first liquor, whereby the rhenium concentration in the second liquor becomes upgraded in the recycling of the first liquor to form a combined product liquor, drawing off excess accumulated product liquor beyond a predetermined quantity, and extracting the rhenium from the drawnoff product liquor.
Claim 5
Dependent Claim
26 words
The method of claim 5, in which the wet-filtering phase includes passage of a flow of the wet-scrubbed, gaseous effluent through a water-wetted thin fibrous screen.
Claim 6
Dependent Claim
25 words
The method of claim 6, in which the screen is wetted by a continuous spray originating within the gaseous flow and upstream from the screen.
Claim 7
Dependent Claim
23 words
The method of claim 6, in which the screen is generally vertically disposed and the flow of water is downward on the screen.
Claim 8
Dependent Claim
14 words
The method of claim 6, in which the fibrous screen is a woven fabric.
Claim 9
Dependent Claim
12 words
The method of claim 9, in which the woven fabric is multiple-ply.
Claim 10
Dependent Claim
29 words
The method of claim 9, in which the woven fabric comprises multiple layers of single-ply material in overlapping adjacency and transverse to the flow of the wet-scrubbed gaseous effluent.
Claim 11
Dependent Claim
28 words
The method of claim 9, in which the woven fabric is selected from the group consisting of wettable metal fibers and synthetic fibers of polyester, polypropylene and polyvinylchloride.
Claim 12
Dependent Claim
15 words
The method of claim 12, in which the fabric is a weave of monofilament fiber.
Claim 13
Dependent Claim
17 words
The method of claim 13, wherein the mesh-opening is in the range of 10 to 200 microns.
Claim 14
Dependent Claim
17 words
The method of claim 13, wherein the mesh-opening is in the range of 30 to 125 microns.
Claim 15
Dependent Claim
15 words
The method of claim 5, in which all steps prior to draw-off are performed continuously.
Claim 16
Dependent Claim
25 words
The method of claim 5, in which the second liquor is recycled in the wet-filtering phase prior to adding the same to the first liquor.
Claim 17
Dependent Claim
32 words
The method of claim 17, in which the recycled second liquor is accumulated to the extent of a second given quantity, prior to drawing off excess for addItion to the first liquor.
Claim 18
Dependent Claim
35 words
The method of claim 17, in which, once the predetermined quantity has been accumulated, the flow of water in the wet-filtering step is derived from the water-vapor content of the gaseous output of the wet-scrubbing.
Claim 19
Dependent Claim
29 words
The method of claim 5, in which the wet-scrubbing step is performed by venturi-scrubbing at an energy level that is at least no greater than a medium energy level.
Claim 20
Dependent Claim
24 words
The method of claim 20, in which the energy level of venturi action is in the water-column pressure range of 12 to 30 inches.
Claim 21
Dependent Claim
111 words
In the recovery of rhenium from a rhenium-containing sulfide concentrate, wherein the concentrate is roasted to provide a rhenium-containing roaster gas which is dust-cleaned and then wet-scrubbed with water to produce a rhenium-bearing liquor and a wet-scrubbed gaseous effluent, and wherein a predetermined accumulated quantity of the liquor is recycled in the wet-scrubbing phase, the improvement which comprises: wet-filtering with water the wet-scrubbed gaseous effluent to produce a second rhenium-bearing liquor, adding the second liquor to the recycling supply of the first liquor to upgrade the rhenium concentration in the second liquor and thereby produce a product liquor, and extracting the rhenium from excess product liquor drawn beyond the predetermined quantity.
Claim 22
Dependent Claim
130 words
In the recovery of rhenium from concentrates selected from the group consisting of molybdenum sulfide and copper sulfide concentrates, wherein the gaseous output of roasting the material is dust-cleaned and then wet-scrubbed with water to produce a first rhenium-bearing liquor and a wet-scrubbed gaseous effluent, and wherein a predetermined accumulated quantity of the first liquor is recycled in the wet-scrubbing phase, the rhenium being extracted from drawn-off liquor to the extent of the excess over said quantity, the improvement which comprises: wet-filtering with water the wet-scrubbed gaseous effluent to produce a second rhenium-bearing liquor, recycling a predetermined quantity of the second liquor in the wet-filtering phase, drawing off excess second liquor beyond the predetermined quantity thereof, and mixing the excess second liquor with the first liquor prior to rhenium extraction.
Claim 23
Dependent Claim
128 words
In the recovery of rhenium from concentrates selected from the group consisting of molybdenum sulfide and copper sulfide concentrates, wherein the gaseous output of roasting the material is dust-cleaned and then wet-scrubbed with water to produce a first rhenium-bearing liquor and a wet-scrubbed gaseous effluent, and wherein a predetermined quantity of the liquor is accumulated and used in the wet-scrubbing phase, the rhenium being extracted from drawn-off liquor to the extent of the excess over said quantity, the improvement which comprises: wet-filtering with water the wet-scrubbed gaseous effluent to produce a second rhenium-bearing liquor, accumulating and using a predetermined quantity of the second liquor as recycle in the wet-filtering phase, and extracting rhenium from liquor drawn off from accumulations of said second liquor beyond said second predetermined quantity.
Claim 24
Dependent Claim
66 words
In the recovery of rhenium from a dust-cleaned rhenium-containing gas, the improved method which comprises wet-scrubbing the gas with recycled rhenium-bearing water liquor, thereby enriching the liquor and producing a first quantity of rhenium-enriched liquor and a wet-scrubbed gaseous effluent, wet-filtering with recycled rhenium-bearing water liquor the wet-scrubbed gaseous effluent to produce a second quantity of rhenium-enriched liquor, and extracting rhenium from both said rhenium-enriched liquors.
Claim 25
Dependent Claim
33 words
The method of claim 25, in which the second liquor is used in the supply of recycled liquor in the wet-scrubbing phase, whereby the second liquor is further enriched prior to rhenium extraction.
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) | 1976-06-18 | 1976-12-18 | 1977-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-18 | 1980-12-18 | 1981-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-18 | 1984-12-18 | 1985-06-19 | $7700.00 | Window Closed / Lapsed |