US3871867A - Roast-flotation process for upgrading molybdenite flotation concentrates - Google Patents
Roast-flotation process for upgrading molybdenite flotation concentrates Download PDFInfo
- Publication number
- US3871867A US3871867A US320167A US32016773A US3871867A US 3871867 A US3871867 A US 3871867A US 320167 A US320167 A US 320167A US 32016773 A US32016773 A US 32016773A US 3871867 A US3871867 A US 3871867A
- Authority
- US
- United States
- Prior art keywords
- flotation
- molybdenite
- diluent
- concentrate
- accordance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 229910052961 molybdenite Inorganic materials 0.000 title claims abstract description 69
- CWQXQMHSOZUFJS-UHFFFAOYSA-N molybdenum disulfide Chemical compound S=[Mo]=S CWQXQMHSOZUFJS-UHFFFAOYSA-N 0.000 title claims abstract description 69
- 238000005188 flotation Methods 0.000 title claims abstract description 65
- 239000012141 concentrate Substances 0.000 title claims abstract description 55
- 238000000034 method Methods 0.000 title claims description 36
- 239000000463 material Substances 0.000 claims abstract description 60
- 239000003085 diluting agent Substances 0.000 claims abstract description 55
- 239000000203 mixture Substances 0.000 claims abstract description 16
- 239000007787 solid Substances 0.000 claims abstract description 9
- 150000004763 sulfides Chemical class 0.000 claims abstract description 7
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 13
- 239000003153 chemical reaction reagent Substances 0.000 claims description 10
- 229910052569 sulfide mineral Inorganic materials 0.000 claims description 10
- 239000006004 Quartz sand Substances 0.000 claims description 8
- 229910052802 copper Inorganic materials 0.000 claims description 8
- 239000010949 copper Substances 0.000 claims description 8
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 7
- 238000011084 recovery Methods 0.000 claims description 7
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 claims description 6
- 238000012216 screening Methods 0.000 claims description 6
- 235000019738 Limestone Nutrition 0.000 claims description 5
- 239000006028 limestone Substances 0.000 claims description 5
- 238000002386 leaching Methods 0.000 claims description 4
- MBMLMWLHJBBADN-UHFFFAOYSA-N Ferrous sulfide Chemical class [Fe]=S MBMLMWLHJBBADN-UHFFFAOYSA-N 0.000 claims description 3
- 239000011362 coarse particle Substances 0.000 claims description 2
- 239000000126 substance Substances 0.000 claims description 2
- 229910052683 pyrite Inorganic materials 0.000 abstract description 9
- NIFIFKQPDTWWGU-UHFFFAOYSA-N pyrite Chemical compound [Fe+2].[S-][S-] NIFIFKQPDTWWGU-UHFFFAOYSA-N 0.000 abstract description 9
- 239000011028 pyrite Substances 0.000 abstract description 9
- OMZSGWSJDCOLKM-UHFFFAOYSA-N copper(II) sulfide Chemical compound [S-2].[Cu+2] OMZSGWSJDCOLKM-UHFFFAOYSA-N 0.000 abstract description 8
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 abstract description 5
- 239000004576 sand Substances 0.000 abstract description 5
- 238000000926 separation method Methods 0.000 abstract description 5
- -1 sulfides Chemical compound 0.000 abstract description 5
- 239000010445 mica Substances 0.000 abstract description 4
- 229910052618 mica group Inorganic materials 0.000 abstract description 4
- 239000000047 product Substances 0.000 description 17
- 229910052500 inorganic mineral Inorganic materials 0.000 description 4
- 239000011707 mineral Substances 0.000 description 4
- BWFPGXWASODCHM-UHFFFAOYSA-N copper monosulfide Chemical class [Cu]=S BWFPGXWASODCHM-UHFFFAOYSA-N 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000009533 lab test Methods 0.000 description 2
- 238000005272 metallurgy Methods 0.000 description 2
- 229910000476 molybdenum oxide Inorganic materials 0.000 description 2
- PQQKPALAQIIWST-UHFFFAOYSA-N oxomolybdenum Chemical compound [Mo]=O PQQKPALAQIIWST-UHFFFAOYSA-N 0.000 description 2
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 1
- 235000011941 Tilia x europaea Nutrition 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000009849 deactivation Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000003701 inert diluent Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000006069 physical mixture Substances 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D1/00—Flotation
- B03D1/08—Subsequent treatment of concentrated product
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03B—SEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS
- B03B1/00—Conditioning for facilitating separation by altering physical properties of the matter to be treated
- B03B1/02—Preparatory heating
Definitions
- a molybdenite flotation concentrate usually a copper sulfide concentrate containing considerable molybdenite as well as other sulfides, such as pyrite, and a relatively small amount of siliceous gangue, is upgraded by, first, adding thereto inert, particulate solid, diluent material that can be easily removed subsequent to roast-conditioning treatment of the concentrate, for example, relatively coarse sand, finely ground mica, or crushed or ground limestone, in sufficient quantity to permit abnormally high roasting temperatures without igniting the charge; then, by roasting the resulting mixture at an abnormally high temperature, usually a temperature that, but for the presence of the diluent material', would ignite the charge and oxidize the molybdenite; and, finally, by treating the roasted concentrate by flotation for recovering the molybdenite as an upgraded molybdenite concentrate.
- inert, particulate solid, diluent material that can be easily removed subsequent to roast-conditioning treatment of the concentrate, for
- the molybdenite is upgraded by flotation treatment of the roasted concentrate in conventional manner, such flotation treatment is facilitated by the higher than normal temperature to which the material has been subjected during the roasting step.
- the diluent material is removed by appropriate separation steps applied either to the roasted product before flotation of some subsequent stage.
- the invention is in the narrow but important field of upgrading flotation concentrates containing considerable quantities of molybdenite.
- copper sulfide ores contain relatively small amount of molybdenite (M05 Both the copper sulfide minerals and the molybdenite are conventionally concentrated in common by floatation, resulting in a general flotation concentrate containing varying amounts of molybdenite, depending upon the ore and the number of cleaning steps utilized.
- Such copper sulfide concentrate usually also contains pyrite and some gangue materials, and is normally further treated to produce a molybdenite flotation concentrate in which either copper sulfides or molybdenite predominates.
- a common procedure for separating the molybdenite from the copper sulfides, pyrite, and gangue materials remaining in such molybdenite flotation concentrate is to filter the concentrate and deactivate the copper sulfides, pyrite, and gangue materials therein by roasting. The roasted concentrate is then repulped and subjected to flotation for upgrading the molybdenite content.
- the common practice is to operate at a temperature below the optimum (e.g. between 450F and 550F) rather than to risk ignition of the charge in the roaster.
- a molybdenite concentrate is mixed with a sufficient quantity of an inert, particulate solid, diluent material to enable roasting at an abnormally high temperature, i.e., above 550F.
- the diluent material must be of a type easily recoverable at some convenient time following roasting of the mixture. Quartz sand of coarse grain size relative to the finely ground solids in an ore pulp, crushed or ground limestone, and finely ground micaceous material are ideal diluent materials.
- the mixture of diluent material and molybdenite concentrate is usually subjected to roasting in a furnace, such as a multiple hearth roaster, at a temperature in the neighborhood of-600F. or above as high as 760 having been successfully employed) for a time sufficient to deactivate the copper and other sulfide minerals, substantially without igniting such minerals or converting the molybdenite in the concentrate to a molybdenum oxide.
- the molybdenite is upgraded by flotation and the inert diluent material is separated for reuse in the process.
- the manner of removing the diluent material will depend upon its nature and whether it follows the molybdenite or remains with the residue. For example, if it is coarse sand or the like, it is removed by screening of the roasted concentrate prior to flotation; if it is finely ground micaceous material, it is removed by flotation of the roasted mixture, using only a frother as a reagent; if it is crushed or ground limestone, it is removed by leaching the roasted mixture after separation of the'molybdenite therefrom.
- the molybdenite concentrate subjected to upgrading procedures in accordance with the invention is normally a copper sulfide flotation concentrate containing considerable quantity of molybdenite.
- the quantity may vary from 5 percent by weight to as high as percent, depending upon the mining property from which the original ore was obtained and the milling procedures applied to it.
- the molybdenite concentrate contains from 5 to 15 percent by weight M08
- Such molybedenite flotation concentrate is intimately mixed with an inert, particulate solid, diluent material, which, in this instance, is a coarse quartz sand having a grain size larger than the size of the particles of ore in the concentrate.
- the quantity of the diluent material necessary to achieve the purposes of the invention will vary in accordance with the particular feed material, etc., but should be at least enough to be effective in preventing ignition of the charge and oxidation of the molybdenite therein when the abnormally high roasting temperatures (i.e., above 550F.) are employed in accordance with the invention.
- diluent materials such as mica or crushed limestone
- the diluent must be inert to the reaction in the roaster and physically recoverable from the roasted concentrate.
- Part of the diluent may be naturally present in the ore material itself as gangue.
- the resulting mixture of molybdenite concentrate and diluent material is subjected to roasting in a suitable furnace, such as a multiple hearth roaster, to deactivate the copper, iron, and various sulfides other than molydbenite, without altering the surfaces of the particles of molybdenite.
- a suitable furnace such as a multiple hearth roaster
- temperatures of at most between 550F. and 600F. have heretofore been attainable without ignition of the copper and iron sulfides, though in commercial practice temperatures above 550F. are not normally employed
- the mixture containing the diluent material can be heated to usual ignition temperatures of 600F. and above, without danger of igniting the furnace charge. For example, temperatures of 650F. to 750F.
- Such high temperatures provide for almost complete alteration of the surfaces of sulfide minerals other than molybdenite, and, therefore, permit more selective separation of the molybdenite from such sulfide minerals in subsequent separation steps.
- the higher temperatures ensure complete removal of flotation reagents, and enhance the floatability of micaceous gangue materials in subsequent flotation steps.
- the period of time necessary to deactivate minerals in the roaster will vary with the concentration of such minerals, the roasting temperature, and the amount of diluent material in the mixture.
- the mixture After the mixture has been roasted, it is screened to separate the coarse grained quartz sand diluent from the relatively fine ore particles. Such diluent can then be recycled for continued use in the process.
- the remaining roasted molybdenite concentrate is subjected to conventional gangue flotation with a frother reagent, such as an alcohol, to float the gangue materials, including any micaceous gangue that might be naturally present as a further diluent, leaving the mineral sulfides as a sink product.
- a frother reagent such as an alcohol
- finely ground mica or micaceous material is employed as the added diluent, it is separated from the roasted concentrate by means of the aforementioned gangue flotation procedure, the screening stage being eliminated.
- An upgraded molybdenite final product results from subjecting the sulfide concentrate obtained from gangue flotation to the usual flotation treatment with a collector reagent, such as burner oil, for recovering molybdenite in the froth.
- a collector reagent such as burner oil
- Crushed or ground limestone as the diluent can be effectively eliminated from the sulfide tailings obtained from the floatation step applied to the sulfide concentrate by leaching such tailings with hydrochloric acid.
- the dissolved lime can be precipitated from the acid leach solution by known procedures for recycling.
- the following laboratory tests demonstrate the effectiveness of the process.
- EXAMPLE I A 200 gram sample of molybdenite flotation concentrate was mixed with 800 grams of -+30 mesh Ottawa (quartz) sand. The mixture was then heat-treated in an open pan in a laboratory muffle furnace with rabbling. The charge was heated to a temperature of 700F. and held at temperatures between 700F. and 750F. for minutes. The charge was then cooled, the Ottawa sand removed by screening, and the recovered, heat-treated sample subjected to flotation for the removal of micaceous gangue by flotation with an alcohol frother, followed by flotation of molybdenite with burner oil as the collector. The following flotation metallurgy was achieved.
- Example ll established that, in the heat-treatment step, the temperature could be maintained between 600F. and 630F. without developing ignition and burning ofthe sample
- 89.3 percent of the molybdenite was recovered as a froth concentrate, nearly twice the recovery effected in Example lll in which lack of effective control pursuant to the invention resulted in ignition of the charge.
- Example 1 established that high temperatures of 700F. to 750F. could be reached in the heattreatment step with, at the most, minor adverse effects upon subsequent flotation processing.
- Example lll the temperature limit to which a particular mixed molybdenite-chalcopyrite-pyritesiliceous gangue mixture could be heated in an open air atmosphere was shown. In this instance, ignition was observed at 600F., temperatures increased rapidly because of burning" of the charge. In subsequent flotation, only 46.8 percent of the molybdenite could be recovered as a froth concentrate.
- a process in accordance with claim diluent is removed from the roast product by a flotation stage in the flotation of said product.
- the diluent is selected from one or more of the group consisting of quartz sand, micaceous material, and limestone.
- diluent comprises quartz sand of relatively coarse particle sizefwhich is removed from the roast product by screening said material prior to flotation.
- the diluent comprises micaceous material which is re,- moved from the roast product in a gangue flotation stage utilizing only a frother reagent.
- the diluent comprises limestone which is removed from the roast product by chemical leaching of a flotation product containing same.
- roasting temperature is within a range of from 550 to 760F.
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- Chemical & Material Sciences (AREA)
- Dispersion Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
Description
Claims (11)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US320167A US3871867A (en) | 1973-01-02 | 1973-01-02 | Roast-flotation process for upgrading molybdenite flotation concentrates |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US320167A US3871867A (en) | 1973-01-02 | 1973-01-02 | Roast-flotation process for upgrading molybdenite flotation concentrates |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3871867A true US3871867A (en) | 1975-03-18 |
Family
ID=23245174
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US320167A Expired - Lifetime US3871867A (en) | 1973-01-02 | 1973-01-02 | Roast-flotation process for upgrading molybdenite flotation concentrates |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3871867A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4058395A (en) * | 1973-09-28 | 1977-11-15 | Michael John Sole | Extracting copper from sulphide concentrates |
| US4120697A (en) * | 1977-04-15 | 1978-10-17 | Amax Inc. | Segregation-separation of copper from nickel in copper-nickel sulfide concentrates |
| US4437884A (en) | 1980-11-10 | 1984-03-20 | Union Oil Company Of California | Ore roasting with recycle of gases |
| US4518573A (en) * | 1983-03-03 | 1985-05-21 | Occidental Chemical Corporation | Differential flotation reagent and method of preparation |
| CN105013616A (en) * | 2015-06-26 | 2015-11-04 | 湖南有色金属研究院 | Method for separating molybdenum concentrate and lead-sulfur concentrate from molybdenum-lead-sulfur mixed concentrate |
| CN106492993A (en) * | 2016-10-30 | 2017-03-15 | 长春黄金研究院 | Suppress the composite restrainer of particulate silicate gangue |
| CN108160340A (en) * | 2017-12-02 | 2018-06-15 | 长春黄金研究院 | A kind of super low concentration copper-cobalt ore method for floating |
| CN112871439A (en) * | 2020-12-24 | 2021-06-01 | 云南迪庆有色金属有限责任公司 | Industrial production method for separating fine-grained copper-molybdenum bulk concentrate by using pulsating high-gradient magnetic separation technology |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1492818A (en) * | 1920-01-08 | 1924-05-06 | Edwin B Thornhill | Process of producing sponge iron |
| US1801105A (en) * | 1926-11-03 | 1931-04-14 | R H Channing Jr | Process of sulphide ore treatment |
| US1865153A (en) * | 1930-01-31 | 1932-06-28 | Metals Production Of North Ame | Heat treatment of copper ores or the like |
| US2674612A (en) * | 1948-11-26 | 1954-04-06 | Standard Oil Dev Co | Controlling reaction temperatures |
| US3427148A (en) * | 1966-10-10 | 1969-02-11 | Bergwerksverband Gmbh | Process of producing iron-coke bodies |
| US3585023A (en) * | 1968-08-20 | 1971-06-15 | Dravo Corp | Method and apparatus for reduction of iron ore |
| US3630501A (en) * | 1970-08-21 | 1971-12-28 | Air Prod & Chem | Thermal treatment of powder |
-
1973
- 1973-01-02 US US320167A patent/US3871867A/en not_active Expired - Lifetime
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1492818A (en) * | 1920-01-08 | 1924-05-06 | Edwin B Thornhill | Process of producing sponge iron |
| US1801105A (en) * | 1926-11-03 | 1931-04-14 | R H Channing Jr | Process of sulphide ore treatment |
| US1865153A (en) * | 1930-01-31 | 1932-06-28 | Metals Production Of North Ame | Heat treatment of copper ores or the like |
| US2674612A (en) * | 1948-11-26 | 1954-04-06 | Standard Oil Dev Co | Controlling reaction temperatures |
| US3427148A (en) * | 1966-10-10 | 1969-02-11 | Bergwerksverband Gmbh | Process of producing iron-coke bodies |
| US3585023A (en) * | 1968-08-20 | 1971-06-15 | Dravo Corp | Method and apparatus for reduction of iron ore |
| US3630501A (en) * | 1970-08-21 | 1971-12-28 | Air Prod & Chem | Thermal treatment of powder |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4058395A (en) * | 1973-09-28 | 1977-11-15 | Michael John Sole | Extracting copper from sulphide concentrates |
| US4120697A (en) * | 1977-04-15 | 1978-10-17 | Amax Inc. | Segregation-separation of copper from nickel in copper-nickel sulfide concentrates |
| US4437884A (en) | 1980-11-10 | 1984-03-20 | Union Oil Company Of California | Ore roasting with recycle of gases |
| US4518573A (en) * | 1983-03-03 | 1985-05-21 | Occidental Chemical Corporation | Differential flotation reagent and method of preparation |
| CN105013616A (en) * | 2015-06-26 | 2015-11-04 | 湖南有色金属研究院 | Method for separating molybdenum concentrate and lead-sulfur concentrate from molybdenum-lead-sulfur mixed concentrate |
| CN105013616B (en) * | 2015-06-26 | 2017-09-22 | 湖南有色金属研究院 | A kind of method that molybdenum concntrate and lead iron concentrate are separated in the lead sulfide mixed concentrate from molybdenum |
| CN106492993A (en) * | 2016-10-30 | 2017-03-15 | 长春黄金研究院 | Suppress the composite restrainer of particulate silicate gangue |
| CN108160340A (en) * | 2017-12-02 | 2018-06-15 | 长春黄金研究院 | A kind of super low concentration copper-cobalt ore method for floating |
| CN112871439A (en) * | 2020-12-24 | 2021-06-01 | 云南迪庆有色金属有限责任公司 | Industrial production method for separating fine-grained copper-molybdenum bulk concentrate by using pulsating high-gradient magnetic separation technology |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: KENNECOTT CORPORATION, 200 PUBLIC SQUARE, CLEVELAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:KENNECOTT MINING CORPORATION;REEL/FRAME:004815/0063 Effective date: 19870320 Owner name: KENNECOTT MINING CORPORATION Free format text: CHANGE OF NAME;ASSIGNOR:KENNECOTT CORPORATION;REEL/FRAME:004815/0036 Effective date: 19870220 Owner name: KENNECOTT CORPORATION Free format text: CHANGE OF NAME;ASSIGNOR:KENNECOTT COPPER CORPORATION;REEL/FRAME:004815/0016 Effective date: 19800520 |
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| AS | Assignment |
Owner name: GAZELLE CORPORATION, C/O CT CORPORATION SYSTEMS, C Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:RENNECOTT CORPORATION, A DE. CORP.;REEL/FRAME:005164/0153 Effective date: 19890628 |
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| AS | Assignment |
Owner name: KENNECOTT UTAH COPPER CORPORATION Free format text: CHANGE OF NAME;ASSIGNOR:GAZELLE CORPORATION;REEL/FRAME:005604/0237 Effective date: 19890630 |