Systems and methods for separating mine tailings from water-absorbing polymers and regenerating the separated water-absorbing polymers

Patent metadata

Field	Value
Publication number	US-9457295-B2
Application number	US-201414222400-A
Country	US
Kind code	B2
Filing date	Mar 21, 2014
Priority date	Apr 10, 2013
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

Systems and methods for separating mine tailings from water-absorbing polymers and regenerating the separated water-absorbing polymers. The systems and methods include a separation assembly that is configured to receive an augmented mine tailings slurry that includes mine tailings, water, and a swollen water-absorbing polymer. The separation assembly separates the swollen water-absorbing polymer from the augmented mine tailings slurry to produce a dewatered mine tailings slurry. The systems and methods further include a water-absorbing polymer regeneration unit that is configured to receive the swollen water-absorbing polymer. The water-absorbing polymer regeneration unit at least partially releases water from the swollen water-absorbing polymer to produce a regenerated water-absorbing polymer, and as a separate output or product, the released water.

First claim

The invention claimed is:

1. A mine tailings dewatering assembly, comprising:
a mixing unit that is configured to receive a mine tailings slurry, which includes mine tailings, water, and a water-absorbing polymer, to combine the mine tailings slurry with the water-absorbing polymer, and to generate an augmented mine tailings slurry therefrom, wherein the mixing unit includes at least one of a transfer pipe, a static mixer, and a stirred tank;
a separation assembly configured to receive the augmented mine tailings slurry, which includes the mine tailings, the water, and a swollen water-absorbing polymer, and to separate the swollen water-absorbing polymer from the augmented mine tailings slurry to produce a dewatered mine tailings slurry; and
a water-absorbing polymer regeneration unit configured to receive the swollen water-absorbing polymer, to at least partially release water from the swollen water-absorbing polymer, and to produce a regenerated water-absorbing polymer therefrom.

2. The assembly of claim 1 , further comprising:
a transfer pipe that is configured to transport the mine tailings slurry between a mine tailings generation site and the mixing unit;
a mine tailings disposal site that is configured to receive the dewatered mine tailings slurry from the separation assembly;
an electrokinetic separator that defines at least a portion of the water-absorbing polymer regeneration unit; and
at least one of:
(i) a regenerated water-absorbing polymer recycle structure that is configured to transport the regenerated water-absorbing polymer from the water-absorbing polymer regeneration unit to the mixing unit; and
(ii) a released water recycle structure that is configured to transport the released water from the water-absorbing polymer regeneration unit to the mine tailings generation site.

3. The assembly of claim 1 , wherein the separation assembly includes at least one of a vibrating screen, an air table, an air classifier, a fluidized bed separator, and a trammel.

4. The assembly of claim 1 , wherein the water-absorbing polymer regeneration unit includes an electrokinetic separator.

5. The assembly of claim 4 , wherein the electrokinetic separator includes an anode and a cathode, wherein the electrokinetic separator is configured to apply an electric field between the anode and the cathode to provide a motive force for release of water from the swollen water-absorbing polymer, wherein the anode is defined by a spiral auger, wherein the cathode is defined by a cylindrical screen that surrounds a radial periphery of the spiral auger, and wherein the spiral auger is configured to rotate within the cylindrical screen to convey at least one of the swollen water-absorbing polymer and the regenerated water-absorbing polymer along a length of the spiral auger.

6. The assembly of claim 1 , wherein the water-absorbing polymer regeneration unit includes at least one of an evaporator, an air blower, a heater, a chiller, a compression device, and a storage tank.

7. The assembly of claim 1 , wherein the water-absorbing polymer regeneration unit further includes a reconstituting unit that is configured to regulate at least one of (i) a shape of the regenerated water-absorbing polymer and (ii) a size of the regenerated water-absorbing polymer.

8. The assembly of claim 7 , wherein the reconstituting unit includes at least one of a mold and a pair of parallel plates.

9. The assembly of claim 1 , further comprising a regenerated water-absorbing polymer recycle structure that is configured to transport at least a portion of the regenerated water-absorbing polymer from the water-absorbing polymer regeneration unit to the mixing unit.

10. The assembly of claim 1 , wherein the released water forms a portion of a released water stream that includes solid particles and the released water, and wherein the mine tailings dewatering assembly further comprises a solid-liquid separation unit that is configured to receive the released water stream and to separate the released water stream into a solid particles stream, which includes at least a portion of the solid particles, and a liquid stream, which includes at least a portion of the released water.

11. The assembly of claim 10 , further comprising a solid particles recycle structure that is configured to mix the solid particles stream with the mine tailings slurry.

12. The assembly of claim 1 , further comprising a released water recycle structure that is configured to transport at least a portion of the released water to the mine tailings generation site.

13. The assembly of claim 1 , further comprising a mine tailings disposal site, wherein a distance between the mine tailings disposal site and the separation assembly is less than 1000 meters.

Assignees

• Ren Wei
• Tanaka Paul L
• Ortiz Gomez Aaron
• Jajuee Babak A
• Chen Chien-Chiang
• Kaminsky Robert D
• Exxonmobil Upstream Res Co

Inventors

• Ren Wei
• Tanaka Paul L
• Ortiz Gomez Aaron
• Jajuee Babak A
• Chen Chien-Chiang
• Kaminsky Robert D

Classifications

• C02F2303/26

  Reducing the size of particles, liquid droplets or bubbles, e.g. by crushing, grinding, spraying, creation of microbubbles or nanobubbles · CPC title

• C02F11/12

  by de-watering, drying or thickening · CPC title

• C02F1/22

  by freezing · CPC title

• C02F1/004

  using large scale industrial sized filters · CPC title

• C02F1/4698

  electro-osmosis · CPC title