Dimensionally controlled ‘engineered polymer bubble’ for flotation separation

Patent metadata

Field	Value
Publication number	US-10245597-B2
Application number	US-201314387692-A
Country	US
Kind code	B2
Filing date	Apr 1, 2013
Priority date	Mar 30, 2012
Publication date	Apr 2, 2019
Grant date	Apr 2, 2019

Abstract

Apparatus is provided featuring a first and second cells. The first cell receives an ore slurry having mineral particles of interest, receives unexpanded polymer microspheres comprising a surface having mineral collector chemistry attached thereto with molecules for attaching the mineral particles of interest, causes the unexpanded polymer microspheres to expand substantially in volume into expanded polymer microspheres having a substantially increased sphere surface area, and provides an expanded polymer microsphere foam layer comprising the expanded polymer microspheres with attached mineral particles of interest. The second cell receives the expanded polymer microsphere foam layer, and causes the expanded polymer microspheres to collapse substantially in volume into collapsed polymer microspheres having a substantially reduced sphere surface area that results in a mechanical shearing off of the attached mineral particles of interest. The second cell may also provide a mineral concentrate output having the mineral particles of interest.

First claim

What is claimed is:

1. A method comprising:
receiving unexpanded polymer microspheres and an ore slurry having mineral particles in a first cell, the unexpanded polymer microspheres comprising a surface having mineral collector chemistry attached thereto with molecules for attaching the mineral particles, causing the unexpanded polymer microspheres to expand in volume into expanded microspheres having an increased sphere surface area, and providing an expanded polymer microsphere foam layer comprising the expanded polymer microspheres with attached mineral particles; and
receiving the expanded polymer microsphere foam layer in a second cell, and causing the expanded polymer microspheres to collapse in volume into collapsed polymer microspheres having a reduced sphere surface area that results in a mechanical shearing off of the attached mineral particles.

2. A method according to claim 1 , wherein the first cell comprises a flotation cell.

3. A method according to claim 2 , wherein the mineral particles are chalcopyrite.

4. A method according to claim 1 , wherein the method comprises configuring the first cell with an agitator to cause or induce agitation to mix the ore slurry and polymer microspheres.

5. A method according to claim 1 , wherein the method comprises configuring the unexpanded polymer microspheres with a blowing agent encapsulated therein that has a trigger temperature set below a predetermined temperature so as to cause the unexpanded polymer microspheres to expand in volume into the expanded polymer microspheres having the increased sphere surface area when received in the first cell.

6. A method according to claim 5 , wherein the method comprises configuring the blowing agent with a liquid that responds to a change in temperature and transforms into a gas.

7. A method according to claim 5 , wherein the method comprises configuring the blowing agent with a gas that responds to a change in temperature and transforms from a lower pressure phase into a higher pressure phase.

8. A method according to claim 5 , wherein the method comprises filling the second cell with the expanded polymer microsphere foam layer or mineral rich foam, and pressurizing the expanded polymer microsphere foam layer or mineral rich foam to an elevated level, or chilling the expanded polymer microsphere foam layer or mineral rich foam to a lower temperature, such that the blowing agent reverses through a transition phase to return from a gas phase to a liquid phase or from a higher pressure phase to a lower pressure phase.

9. A method according to claim 1 , further comprising maintaining the ore slurry at a predetermined temperature in the first cell, and the unexpanded polymer microspheres are configured with a blowing agent encapsulated therein that has a trigger temperature set below the predetermined temperature so as to cause the unexpanded polymer microspheres to expand in volume into the expanded polymer microspheres having the increased sphere surface area when received in the first cell.

10. A method according to claim 9 , wherein the method comprises cooling or chilling the unexpanded polymer microspheres to a temperature below the predetermined temperature before the unexpanded polymer microspheres are received into the first cell.

11. A method according to claim 1 , wherein the expanded polymer microspheres are configured to become buoyant and create an increased bubble flux in the ore slurry, presenting surface area for mineral bearing particles to attach to and be lifted to the surface and form the expanded polymer microsphere foam layer.

12. A method according to claim 1 , wherein the expanded polymer microsphere foam layer takes the form of an agglomerated mass of expanded spheres on the surface, said method further comprising skimming and moving the agglomerated mass to or spilling the agglomerated mass over into a spillover container and then moving the agglomerated mass to the second cell.

13. A method according to claim 1 , wherein the method comprises configuring the second cell as a release tank in the form of a re-pressurization cell or tank or a condensation cell or tank configured to collapse the expanded polymer microspheres in volume into the collapsed polymer microspheres that results in the mechanical shearing off of the attached mineral particles.

14. A method to claim 1 , wherein the method comprises separating the mineral particles from the collapsed polymer microspheres based at least partly on or due to gravitation separation, including where the mineral particles sink in the second cell and the collapsed polymer microspheres remain buoyant and float.

15. A method according to claim 1 , wherein the method comprises providing either a mineral concentrate output having the mineral particles, or a discarded foam output having the collapsed polymer microspheres, or both from the second cell.

16. A method according to claim 1 , wherein the method comprises configuring the molecules with a functional group for attaching the mineral particles.

17. A method according to claim 1 , wherein the volume of the expanded polymer microspheres is about 50 times the volume of the unexpanded polymer microspheres.

18. Apparatus comprising:
a first cell comprising a flotation cell having a top part and a bottom part, the top part configured to receive an ore slurry having mineral particles, the bottom part configured to receive unexpanded polymer microspheres comprising a surface having mineral collector chemistry attached thereto with molecules for attaching the mineral particles, wherein the first cell is configured to maintain the ore slurry at a predetermined temperature, and the unexpanded polymer microspheres are configured with a blowing agent encapsulated therein that has a trigger temperature set below the predetermined temperature so as to cause the unexpanded polymer microspheres to expand in volume into expanded polymer microspheres having an increased sphere surface area when received in the first cell, the first cell further configured to provide an expanded polymer microsphere foam layer comprising the expanded polymer microspheres with attached mineral particles; and
a second cell configured to receive the expanded polymer microsphere foam layer, wherein the second cell comprises a release tank in the form of a re-pressurization cell or tank or a condensation cell or tank configured to cause the expanded polymer microspheres to collapse in volume into collapsed polymer microspheres having a reduced sphere surface area that results in a mechanical shearing off of the attached mineral particles.

19. Apparatus according to claim 18 , wherein the first cell comprises an agitator configured to cause or induce agitation to mix the ore slurry and the unexpanded polymer microspheres or the expanded polymer microspheres or both.

20. Apparatus according to claim 18 , wherein the blowing agent comprises a liquid that responds to a change in temperature and transforms into a gas.

21. Apparatus according to claim 18 , wherein the blowing agent comprises a gas that responds to a change in temperature and transforms from a lower pressure phase into a higher pressure phase.

22. Apparatus according to claim 18 , wherein the unexpanded polymer microspheres are cooled or chilled to a temperature below the predetermined temperature before the unexpanded polymer microspheres are received into the first cell.

23. Apparatus according to claim 18 , wherein the expanded polymer mic

Assignees

• Cidra Corporate Services Inc

Inventors

• Didden Francis K
• Kersey Alan D
• Davis Michael A
• Rothman Paul J
• Fernald Mark R
• O'Keefe Christian V
• Adamson Douglas H

Classifications

• B03D1/082

  of the froth product, e.g. washing · CPC title

• B03D1/02

  Froth-flotation processes · CPC title

• B03D2203/02

  Ores · CPC title

• C02F1/24

  by flotation (C02F1/465 takes precedence) · CPC title

• B03D1/1406

  with special arrangement of a plurality of flotation cells, e.g. positioning a flotation cell inside another · CPC title