Andrew J Sharpe

US Patent:

46473823, Mar 3, 1987

Filed:

Jun 12, 1985

Appl. No.:

6/744020

Inventors:

Andrew J. Sharpe - Comfort WV

International Classification:

C02F 156

US Classification:

210710

Abstract:

Aqueous mineral slurries containing 10% by weight or more of finely divided mineral solids are flocculated prior to dewatering and/or thickening, and prepared for redispersion, by treating the slurries with polymers comprising at least about 1% by weight 2-acrylamido-2-methyl propyl sulfonic acid copolymerized with acrylamide and/or other suitable water-soluble monomers. The polymers must have a Brookfield viscosity of at least 7000 cps at 7. 5% concentration in water. Flocculation of the mineral slurries with these polymers also provides improved re-dispersibility of the dewatered mineral in the filter cake. During redispersion, additional dry mineral may be added to obtain a final solids content as high as 70% or more. The Brookfield viscosity of the final high solids slurry comprising a significant portion of filter cake treated with the flocculants of this invention is lower than that of untreated material.

US Patent:

49902636, Feb 5, 1991

Filed:

Feb 13, 1989

Appl. No.:

7/310247

Inventors:

Andrew J. Sharpe - Comfort WV

International Classification:

C02F 156

US Classification:

210710

Abstract:

Finely divided aqueous mineral slurries such as kaolin clay and calcium carbonate are dewatered, filtered and prepared for shipment by and with the addition of an effective amount (preferably 0. 01 to 4. 0 pounds per ton of solids) of melamine/formaldehyde polymer.

US Patent:

49902628, Feb 5, 1991

Filed:

Feb 13, 1989

Appl. No.:

7/310249

Inventors:

Andrew J. Sharpe - Comfort WV

International Classification:

C02F 156

US Classification:

210710

Abstract:

Aqueous mineral slurries are treated prior to dewatering, to increase throughput, with a condensation product of formaldehyde and dicyandiamide, which may be further reacted with ammonia or an ammonia salt and an alkylenepolyamine or copper chloride.

US Patent:

47418389, May 3, 1988

Filed:

Jun 11, 1986

Appl. No.:

6/872838

Inventors:

Andrew J. Sharpe - Comfort WV

International Classification:

C02F 156

US Classification:

210710

Abstract:

Aqueous mineral slurries containing 10% by weight or more of finely divided mineral solids are flocculated prior to dewatering and/or thickening to obtain improved throughput and/or to reduce moisture in the dewatered product, by treating the slurries with polymers comprising at least about 1% by weight 2-acrylamido-2-methyl propyl sulfonic acid copolymerized with acrylamide and/or other suitable water-soluble monomers. The polymers must have a Brookfield viscosity of at least 7000 cps at 7. 5% concentration in water. Flocculation of the mineral slurries with these polymers also provides improved re-dispersibility of the dewatered mineral in the filter cake. During redispersion, additional dry mineral may be added to obtain a final solids content as high as 70% or more. The Brookfield viscosity of the final high solids slurry comprising a significant portion of filter cake treated with the flocculants of this invention is not detrimentally affected.