Process for flocculating and dewatering oil sand mature fine tailings

Patent metadata

Field	Value
Publication number	US-10590347-B2
Application number	US-201715820707-A
Country	US
Kind code	B2
Filing date	Nov 22, 2017
Priority date	Sep 15, 2009
Publication date	Mar 17, 2020
Grant date	Mar 17, 2020

Abstract

A process for dewatering oil sand fine tailings is provided and comprises a dispersion and floc build-up stage comprising in-line addition of a flocculent solution comprising an effective amount of flocculation reagent into a flow of the oil sand fine tailings; a gel stage wherein flocculated oil sand fine tailings is transported in-line and subjected to shear conditioning; a floc breakdown and water release stage wherein the flocculated oil sand fine tailings releases water and decreases in yield shear stress, while avoiding an oversheared zone; depositing the flocculated oil sand fine tailings onto a deposition area to form a deposit and to enable the release water to flow away from the deposit, preferably done in a pipeline reactor and managing shear according to yield stress and CST information and achieves enhanced dewatering.

First claim

What is claimed is:

1. A process for producing a hydrocarbon product derived from oil sands ore, the process comprising:
forming an aqueous slurry comprising the oil sands ore;
subjecting the aqueous slurry comprising the oil sands ore to separation to produce the hydrocarbon product and fine tailings comprising water and fine solids; and
treating the fine tailings to separate water and fine solids contained therein, wherein the treating comprises:
adding a flocculant solution comprising an effective amount of flocculation reagent in-line into a flow of the fine tailings to cause dispersion of the flocculation reagent and build-up of flocs to form flocculated fine tailings;
transporting the flocculated fine tailings in-line and subjecting the flocculated fine tailings to in-line shear conditioning to increase a yield stress thereof to a peak yield stress and produce an in-line flow of a gel stage tailings material;
subjecting the gel stage tailings material to further in-line shear conditioning to reduce the yield stress from the peak yield stress and produce an in-line flow of an ungelled flocculated tailings material;
discharging the ungelled flocculated tailings material from a pipeline discharge outlet; and
allowing the discharged ungelled flocculated tailings material to undergo solid-liquid separation wherein water separates from flocculated fine solids.

2. The process of claim 1 , wherein the discharging of the ungelled flocculated tailings material is performed onto a solid land surface.

3. The process of claim 2 , wherein the solid-liquid separation includes forming a deposit of discharged ungelled flocculated tailings material and allowing the water to drain and flow away from the deposit.

4. The process of claim 3 , wherein the solid land surface comprises a deposition cell having a sloped bottom surface.

5. The process of claim 1 , wherein the adding of the flocculant solution into the flow of the fine tailings, the in-line shear conditioning to produce the gel stage tailings material, the in-line shear conditioning to form the ungelled flocculated tailings material, up to the discharging thereof, are performed in a pipeline reactor.

6. The process of claim 5 , wherein the pipeline reactor comprises a co-annular injection device for in-line injection of the flocculant solution into the fine tailings.

7. The process of claim 1 , further comprising providing the in-line shear conditioning such that the ungelled flocculated tailings material is discharged from the pipeline discharge outlet when the yield shear stress of the ungelled flocculated tailings material is within a decrease zone following a plateau zone.

8. The process of claim 1 , wherein the in-line shear conditioning to produce the gel stage tailings material and then the ungelled flocculated tailings material is controlled by a pipeline length through which the flocculated fine tailings travels prior to the discharging.

9. The process of claim 1 , wherein the fine tailings are withdrawn from a pond, and no dilution water is added to the fine tailings after the fine tailings are withdrawn from the pond and prior to being treated.

10. A process for producing bitumen from oil sands fine tailings, the process comprising:
retrieving oil sands fine tailings from a tailings pond;
subjecting the oil sands fine tailings to separation to produce recovered bitumen and a bitumen-depleted fine tailings;
treating the bitumen-depleted fine tailings to separate water and fine solids contained therein, wherein the treating comprises:
adding a flocculant solution comprising an effective amount of flocculation reagent in-line into a flow of the bitumen-depleted fine tailings to cause dispersion of the flocculation reagent and build-up of flocs to form flocculated fine tailings;
transporting the flocculated fine tailings in-line and subjecting the flocculated fine tailings to in-line shear conditioning to increase a yield stress thereof to a peak yield stress and produce an in-line flow of a gel stage tailings material;
subjecting the gel stage tailings material to further in-line shear conditioning to reduce the yield stress from the peak yield stress and produce an in-line flow of an ungelled flocculated tailings material;
discharging the ungelled flocculated tailings material from a pipeline discharge outlet; and
allowing the discharged ungelled flocculated tailings material to undergo solid-liquid separation wherein water separates from flocculated fine solids.

11. The process of claim 10 , wherein the discharging of the ungelled flocculated tailings material is performed onto a solid land surface, and the solid-liquid separation includes forming a deposit of discharged ungelled flocculated tailings material and allowing the water to drain and flow away from the deposit.

12. The process of claim 10 , wherein the adding of the flocculant solution into the flow of the fine tailings, the in-line shear conditioning to produce the gel stage tailings material, the in-line shear conditioning to form the ungelled flocculated tailings material, up to the discharging thereof, are performed in a pipeline reactor.

13. The process of claim 12 , wherein the pipeline reactor comprises a co-annular injection device for in-line injection of the flocculant solution into the bitumen-depleted fine tailings.

14. The process of claim 10 , wherein no dilution water is added to the bitumen-depleted fine tailings prior to being treated.

15. A process for producing a mined product from mined ore, the process comprising:
forming an aqueous slurry comprising the ore;
subjecting the aqueous slurry to separation to produce the mined product and fine tailings comprising water and fine solids; and
treating the fine tailings to separate water and fine solids contained therein, wherein the treating comprises:
adding a flocculant solution comprising an effective amount of flocculation reagent in-line into a flow of the fine tailings to cause dispersion of the flocculation reagent and build-up of flocs to form flocculated fine tailings;
transporting the flocculated fine tailings in-line and subjecting the flocculated fine tailings to in-line shear conditioning to increase a yield stress thereof to a peak yield stress and produce an in-line flow of a gel stage tailings material;
subjecting the gel stage tailings material to further in-line shear conditioning to reduce the yield stress from the peak yield stress and produce an in-line flow of an ungelled flocculated tailings material;
discharging the ungelled flocculated tailings material from a pipeline discharge outlet;
allowing the discharged ungelled flocculated tailings material to undergo solid-liquid separation wherein water separates from flocculated fine solids.

16. The process of claim 15 , wherein the discharging of the ungelled flocculated tailings material is performed onto a solid land surface.

17. The process of claim 16 , wherein the solid-liquid separation includes forming a deposit of discharged ungelled flocculated tailings material and allowing the water to drain and flow away from the deposit.

18. The process of claim 15 , wherein the mined product is bitumen and the mined ore is oil sands ore.

19. The process of claim 15 , wherein the adding of the flocculant solution into the flow of the fine tailings, the in-line shear conditioning to produce the gel stage tailings material, the in-line shear conditioning to form the ungelled flocculated tailings material, up to the discharging thereof, are performed in a pipeline reacto

Assignees

• Suncor Energy Centre
• Suncor Energy Inc

Inventors

• Revington Adrian Peter
• Omotoso Oladipo
• Wells Patrick Sean
• Hann Thomas Charles
• Weiss Marvin Harvey
• Bugg Trevor
• Eastwood Jamie
• Young Stephen Joseph
• O'Neill Hugues Robert
• Sanchez Ana Cristina

Classifications

• C10G1/047 Primary

  Hot water or cold water extraction processes · CPC title

• C02F2103/10

  from quarries or from mining activities · CPC title

• C02F1/56

  Macromolecular compounds · CPC title

• C10G33/04

  with chemical means · CPC title

• C02F11/14

  with addition of chemical agents · CPC title