Backfill, methods of making, and use thereof

• US 9,573,849 B2
• Filed: 04/30/2014
• Issued: 02/21/2017
• Est. Priority Date: 02/24/2014
• Status: Active Grant

• Current Assignee: Active Minerals International LLC
• Original Assignee: Active Minerals International LLC
• Inventors: Coetzee, Rudolph M., Purcell, Robert J. Jr., Parker, Dennis C., Fendley, Paul, Feldman, Steven B.
• Primary Examiner(s): Green, Anthony J
• Application Number:
  US14/266,627
• Publication Number:
  US 20150239782A1
• Time in Patent Office: 1,028 Days
• US Class Current: 1/1
• CPC Class Codes: C04B 14/00 Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone expanding or defibrillating materials C04B20/00
• CPC Class Codes: C04B 14/04 Silica-rich materials; Silicates
• CPC Class Codes: C04B 14/043 Alkaline-earth metal silicates, e.g. wollastonite
• CPC Class Codes: C04B 14/047 Zeolites
• CPC Class Codes: C04B 14/06 Quartz; Sand
• CPC Class Codes: C04B 14/10 Clay sepiolite C04B14/042; grog C04B18/025
• CPC Class Codes: C04B 14/102 Attapulgite clay
• CPC Class Codes: C04B 14/28 of calcium
• CPC Class Codes: C04B 18/08 Flue dust , i.e. fly ash
• CPC Class Codes: C04B 18/12 from quarries, mining or the like
• CPC Class Codes: C04B 18/141 Slags
• CPC Class Codes: C04B 18/146 Silica fume
• CPC Class Codes: C04B 18/162 Cement kiln dust; Lime kiln dust
• CPC Class Codes: C04B 2111/00724 in mining operations, e.g. for backfilling; in making tunnels or galleries
• CPC Class Codes: C04B 22/064 of the alkaline-earth metals
• CPC Class Codes: C04B 28/02 containing hydraulic cements other than calcium sulfates
• CPC Class Codes: C04B 28/04 Portland cements
• CPC Class Codes: E21B 43/12 Methods or apparatus for controlling the flow of the obtained fluid to or in wells E21B43/25 takes precedence; valve arrangements E21B34/00
• CPC Class Codes: Y02W 30/91 Use of waste materials as fillers for mortars or concrete

Abstract

A composition in the form of a backfill is described. The composition comprises one or more mine tailings present in an amount greater than 50% by weight of the composition, one or more cementitious binder materials present in an amount ranging from 0% to 12% by weight of the composition, attapulgite present in an amount ranging from 0.01% to 4.00% by weight of the composition, and water. The fines content (Fc) of the one or more mine tailings is greater than or equal to 3%. Although subject to many uses, in some embodiments, the composition is suitable for managing tailings to be stored above ground or underground. For example, in some embodiments, the composition is suitable for filling mined out areas.

Claims

1. A composition, comprising:

one or more mine tailings present in an amount greater than 25% by weight of the composition;

one or more cementitious binder materials present in an amount ranging from 0% to 12% by weight of the composition;

purified attapulgite substantially free of non-attapulgite minerals present in an amount ranging from 0.01% to 0.7% by weight of the composition; and

water;

wherein the fines content (Fc) of the one or more mine tailings is greater than or equal to 3%.

2. The composition of claim 1, wherein the purified attapulgite substantially free of non-attapulgite minerals is present in an amount ranging from 0.02% to 0.15% by weight of the composition.

3. The composition of claim 1, wherein the purified attapulgite substantially free of non-attapulgite minerals is present in an amount ranging from 0.03% to 0.15% by weight of the composition.

4. The composition of claim 1, wherein the fines content (Fc) of the one or more mine tailings ranges from 3% to 20%.

5. The composition of claim 4, wherein the one or more cementitious binder materials are present in an amount ranging from greater than 0% to less than 1% by weight of the composition.

6. The composition of claim 4, wherein the one or more cementitious binder materials are present in an amount ranging from 1% to 12% by weight of the composition.

7. The composition of claim 1, wherein the one or more cementitious binder materials are present in an amount ranging from greater than 0% to less than 1% by weight of the composition.

8. The composition of claim 1, wherein the one or more cementitious binder materials are present in an amount ranging from 1% to 12% by weight of the composition.

9. The composition of claim 1, wherein the one or more mine tailings are present in an amount ranging from 65% to 88%.

10. The composition of claim 1, wherein the one or more cementitious binder materials are chosen from Portland cements and lime.

11. The composition of claim 1, wherein the one or more cementitious binder materials further comprise one or more supplementary cementitious materials.

12. The composition of claim 1, further comprising at least one mineral suspension agent chosen from bentonite, montmorillonite, and sepiolite.

13. The composition of claim 1, wherein the composition has a slump ranging from 140 mm to 260 mm.

14. The composition of claim 1, wherein the composition has a ranging from 250 kPa to 5 MPa.

15. The composition of claim 1, wherein the purified attapulgite substantially free of non-attapulgite minerals is present in an amount ranging from 0.01% to 0.15% by weight of the composition.

16. A method of making a composition, comprising

mixing (a) one or more mine tailings;

(b) one or more cementitious materials;

(c) purified attapulgite substantially free of non-attapulgite minerals; and

(d) water to form a resultant composition;

wherein the (a) one or more mine tailings is present in an amount greater than 50% by weight of the composition;

wherein the (b) one or more cementitious binder materials is present in an amount ranging from 0% to 12% by weight of the composition;

wherein the (c) purified attapulgite substantially free of non-attapulgite minerals is present in an amount ranging from 0.01% to 0.7% by weight of the composition; and

wherein the fines content (Fc) of the one or more mine tailings is greater than or equal to 3%.

17. The method of claim 16, wherein the resultant composition is solidified in a mine tailings storage facility.

18. The method of claim 16, further comprising mixing a coarse component with the resultant composition to form a blend, wherein the coarse component content (Cc) is greater than or equal to 0% and less than or equal to 5%.

19. A method, comprising

mixing (a) one or more mine tailings;

(b) one or more cementitious materials;

(c) purified attapulgite substantially free of non-attapulgite minerals; and

(d) water to form a resultant composition;

wherein the (a) one or more mine tailings is present in an amount greater than 50% by weight of the composition;

wherein the (b) one or more cementitious binder materials is present in an amount ranging from 0% to 12% by weight of the composition;

wherein the (c) purified attapulgite substantially free of non-attapulgite minerals is present in an amount ranging from 0.01% to 0.7% by weight of the composition; and

wherein the fines content (Fc) of the one or more mine tailings is greater than or equal to 3%; and

thereafter transporting the resultant composition via a conduit to a mine tailings storage facility; and

thereafter waiting a period of time sufficient for the resultant transported composition to solidify in the mine tailings storage facility.

20. The method of claim 19, wherein the transporting is chosen from gravity delivery to borehole or decline leading to the mine tailings storage facility;

conveyor delivery to a borehole or a decline leading to the mine tailings storage facility;

a pump delivery thru a borehole or decline leading to the mine tailings storage facility;

vehicle delivery to a borehole or decline leading to the mine tailings storage facility; and

pipeline delivery to a borehole or decline leading to the mine tailings storage facility.