Minerals Engineering, Vol. 4, No. 2, pp. i-ii, 1991 0892-6875/91 $3.00 + 0.00 Printed in Great Britain Pergamon Press plc

NEW PATENTS

This Section contains abstracts and, where appropriate, illustrations of recently issued United States patents and published patent applications filed from over 30 countries under the Patent Cooperation Treaty. This information was obtained from recent additions to the Pergamon PATSEARCH ~ online database in accordance with interest profiles developed by the Editors. Further information about Pergamon PATSEARCH H can be obtained from Pergamon Orbit InfoLine Inc., 8000 Westpark Drive, McLean, Virginia 22102 U.S.A.

Copies of complete patents announced in this Section are available from Pergamon Orbit InfoLine Inc. for $8 per copy. Payment with order is required. Orders outside North America add $2 for air postage. Order by patent number for Pergamon Orbit InfoLine only.

4900767 4910000

PROCESS FOR THE SURFACE MODIFICATION OF MINERALS IN A REACTIVE ATMOSPHERE

Camilla A Rice assigned to E C C America Inc

A method of producing a mineral such as cal- cium carbonate, glass fibers and layered lattice silicates which is surface modified with an or- ganic material wherein said mineral in substan- tially dry, particulate form is contacted with an organic monomer, co-monomers or a pre- polymer, and surface polymerization or reaction in situ on the mineral is carried out in the pre- sence of gaseous carbon monoxide.

4908125

FROTH FLOTATION PROCESS FOR THE RECOVERY OF

MINERALS AND A COLLECTOR COMPOSITION FOR USE

THEREIN

James M Mackenzie, Peter Cabassi, Sandton, South Africa assigned to Henkel Kommandit- gesellschaft auf Aktien

The invention is a collector composition for a flotation process containing a primary or secon- dary amine or amine salt and at least one of xan- thates, dithiophosphates, mercaptobenzothiazoles, xanthogen formate and thioaocarbamate and a flotation process which utilizes the collector composition.

METHOD OF EXTRACTING TUNGSTEN VALUES FROM

TUNGSTEN CONTAINING ORES

Thomas R Davey, Glen Waverley, Australia as- signed to The University of Melbourne

A method of extracting tungsten values from tungsten containing ores comprising step (i) for- ming a mixture of a tungsten containing ore and a first mineral acid adapted to consume acid con- suming substances in the ore and step (ii) thereafter adding organic anions to produce a solution containing dissolved tungsten values.

4911826

SPARGING SYSTEM FOR COLUMN FLOTATION

Peter L Harach, Donald B Waites, Michael A Redfearn, Kimberley, Canada assigned to Com- inco Ltd

A system for sparging aerated water into a column for the froth flotation of minerals, and located in the lower portion of the column, con- sists of water and air supply headers connected to a supply of pressurized water and air, respec- tively. The headers comprise a number of water and air passages, each having shut off valves. A multiplicity of sparger tubes is arranged, in one or more horizontal planes, either radially towards the column center or parallel to each other from opposite sides of the column. Each

ii New Patents

sparger pipe comprises a mixing tee attached to a water passage and an air passage, and a per- forated portion provided with a number of small openings. The number of openings in each pipe is determined by the cross-sectional area covered by the sparger pipe. The openings may be ar- ranged upwardly and/or downwardly at an angle in the range of about 5 degrees to 90 degrees from the horizontal. The openings are preferably arranged in a single row and directed vertically downwardly, or in two parallel rows and direc- ted radially downwardly at an angle of 5 degrees to 75 degrees from the horizontal. Each opening is provided with a wear-resistant material, pre- ferably in the form of an insert and preferably made of tungsten carbide, to reduce erosion of the openings. The number of openings is chosen such that the air bubbles exit from the openings and rise in the column substantially evenly dist- ributed over the entire cross section of the column.

4 9 1 1 8 4 8

M E T H O D F O R N A T U R A L L Y D R Y I N G M I N E R A L P U L P S

Jean-Louis Cardini, Jean-Pierre Fer, Claude Laurent, Paris, France assigned to Eramet-SLN (formerly Societe Metallurgique ie Nickel-SLN

A method of spreading a pulp for the purpose of drying it naturally, the pulp having a solid frac- tion which has a d80 of less than 100 microns. This method comprises the following steps: (a) adjusting the level of solids of the pulp to bet- ween 2 and 25%; (b) adding a flocculating agent to the pulp and mixing it with same, the amount of said flocculating agent being between two-

thirds of 98% of the optimum required fo the flocculation of said pulp; and (c) spreading the mixture of pulp and flocculating agent, in the open air, in a bed the sides of which are per- meable, and the bottom of which has a slope of less than 5 meters per 1000 meters, said spreading taking place 1 to 20 minutes after the adding are mixing of the flocculating agent.

4915731

M E T A L L U R G I C A L M E T H O D A N D A P P A R A T U S

Belton Cooper

Method and apparatus for recovering a metal from an ore by kinetic metallurgy as distinct from the usual static blast furnace approach.

4 9 1 5 8 2 5

P R O C E S S F O R C O A L F L O T A T I O N U S I N G 4 - M E T H Y L

C Y C L O H E X A N E M E T H A N O L F R O T H E R S

Richard Christie, Anthony E Gross, Randall J Fortin assigned to Nalco Chemical Company

An improved froth flotation process wherein solid coal particles are selectively separated un- der coal froth flotation conditions as a froth phase from remaining solid feed particles as an aqueous phase in the presence of a frother, the improvement comprising a frother of at least 4- methyl cyclohexane methanol.

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