A FROTH FLOTATION ARRANGEMENT AND A FROTH FLOTATION METHOD

• US 20200129992A1
• Filed: 07/04/2017
• Published: 04/30/2020
• Est. Priority Date: 07/04/2017
• Status: Active Grant

• Current Assignee: Metso Outotec Finland OY (Metso Outotec Oyj)
• Original Assignee: Outotec (Finland) Oy (Metso Outotec Oyj)
• Inventors: YANEZ, Alejandro, GRAU, Rodrigo
• Granted Patent: US 11,033,909 B2
• Time in Patent Office: Days
• CPC Class Codes: B03D 1/028 Control and monitoring of flotation processes; computer models therefor
• CPC Class Codes: B03D 1/1406 with special arrangement of a plurality of flotation cells, e.g. positioning a flotation cell inside another
• CPC Class Codes: B03D 1/1456 Feed mechanisms for the slurry
• CPC Class Codes: B03D 1/1462 Discharge mechanisms for the froth
• CPC Class Codes: B03D 1/16 with impellers; Subaeration machines mixing gases or vapours with liquids B01F23/20
• CPC Class Codes: B03D 1/242 Nozzles for injecting gas into the flotation tank
• CPC Class Codes: B03D 2203/02 Ores
• CPC Class Codes: C02F 1/24 by flotation C02F1/465 takes precedence
• CPC Class Codes: D21B 1/327 using flotation devices

Abstract

A froth flotation arrangement and method for treating mineral ore particles suspended in slurry includes a flotation cell for separating the slurry into an underflow and an overflow and a primary line including at least three flotation cells connected in series, wherein each subsequent flotation cell is arranged to receive the underflow from the previous flotation cell, the flotation cell includes a tank and an impeller within the tank, and the flotation cell includes a gas supply within the tank, the tank includes a volume of at least 200 m3, the flotation cell including a froth collection launder capable to receive the overflow the froth collection launder including a froth overflow lip, the flotation cell having an available froth surface area (A froth), the flotation cell having a pulp area (A pulp), where the pulp area (A pulp) is calculated as an average from the cross sectional areas of the tank at the height (h1) of the impeller. A ratio between a height (h) from a bottom of the tank to the froth overflow lip of the froth collection launder and the diameter (D) of the tank at the height (h1) of the impeller (h/D) is less than 1.5.

Claims

1-19. -19. (canceled)

20. A froth flotation arrangement for treating mineral ore particles suspended in slurry, comprising a flotation cell for separating the slurry into an underflow and an overflow, wherein the arrangement comprises:

a primary line comprising at least three flotation cells connected in series, wherein each subsequent flotation cell is arranged to receive the underflow from the previous flotation cell,

the flotation cell comprising a tank, and the flotation cell comprising an impeller within the tank, and

the flotation cell comprising a gas supply within the tank,

the tank comprising a volume of at least 200 m³,

the flotation cell comprising a froth collection launder capable to receive the overflow,

the froth collection launder comprising a froth overflow lip,

the flotation cell having an available froth surface area (A_froth),

the flotation cell having a pulp area (A_pulp), where the pulp area (A_pulp) is calculated as an average from the cross sectional areas of the tank at the height (h1) of the impeller,

a ratio between a height (h) from a bottom of the tank to the froth overflow lip of the froth collection launder and the diameter (D) of the tank at the height (h1) of the impeller (h/D) is less than 1.5,

wherein the third flotation cell or subsequent flotation cell in the series has a ratio between an available froth surface area and the pulp area (A_froth/A_pulp) less than 0.45.

21. The froth flotation arrangement according to claim 20, wherein a ratio between a height (h) from a bottom of the tank to the froth overflow lip of the froth collection launder and the diameter (D) of the tank (h/D) is less than 1.1.

22. The froth flotation arrangement according to claim 20, wherein the ratio between the available froth surface area and the pulp area (A_froth/A_pulp) is from 0.1 to 0.45.

23. The froth flotation arrangement according to claim 20, wherein the periphery shape of the froth collection launder shape corresponds the tank periphery shape.

24. The froth flotation arrangement according to claim 20, wherein the froth collection launder comprises an internal peripheral launder or the tank comprises an internal peripheral froth blocker.

25. The froth flotation arrangement according to claim 24, wherein the ratio between the area of the internal peripheral launder and the pulp area (A_{int launder}/A_pulp), or the ratio between the area of the internal peripheral froth blocker and the pulp area (A_{int blocker}/A_pulp), is more than 0.1, preferably more than 0.1 and less than 0.5.

26. The froth flotation arrangement according to claim 20, wherein the tank is circular in cross section at the overflow lip height (h2) of the tank.

27. The froth flotation arrangement according to claim 20, wherein the froth collection launders are circular shaped and positioned coaxially.

28. The froth flotation arrangement according to claim 27, wherein an average froth transport distance (d_tr) is less than 100 cm, preferably is less than 100 cm and more than 5 cm.

29. The froth flotation arrangement according to claim 20, wherein the tank comprises at least three separate froth collection launders.

30. The froth flotation arrangement according to claim 29, wherein the number of overflow lips in the froth collection lounders is five.

31. The froth flotation arrangement according to claim 20, wherein the froth collection launders are positioned in radial direction (r) of the tank.

32. The froth flotation arrangement according to claim 27, wherein a ratio between the average transport distance (d_tr) and a froth collection launder average width (w) in radial direction (r) (d_tr/w) is 0.1-0.6.

33. An arrangement in a froth flotation cell according to claim 20, wherein the gas supply comprises a pipe delivering gas to the bottom part of the tank at least partly under the impeller, or a conduit formed to an agitator comprising the impeller.

34. An arrangement in a froth flotation cell according to claim 20, wherein the flotation cell comprises an agitator comprising an impeller and a stator.

35. A froth flotation method for treating mineral ore particles suspended in slurry, and in the method separating the slurry in a flotation cell into an underflow and an overflow, the method comprising the steps of:

connecting at least three flotation cells in series for creating a primary line,

feeding the slurry to a tank of the flotation cell,

wherein each subsequent flotation cell is receiving the underflow from the previous flotation cell,

introducing gas into the tank through a gas supply,

mixing the slurry and the gas with an impeller within the tank,

providing the tank with a volume of at least 200 m³,

receiving the overflow in a froth collection launder provided in the flotation cell,

receiving the overflow over a froth overflow lip provided in the froth collection launder,

forming an available froth surface area (A_froth) in the flotation cell,

the flotation cell having a pulp area (A_pulp), where the pulp area (A_pulp) is calculated as an average from the cross sectional areas of the tank at the height of the impeller (h1),

providing the tank with a ratio between a height (h) from a bottom of the tank to the froth overflow lip of the froth collection launder and the diameter (D) of the tank at the height (h1) of the impeller of a pulp area (h/D) being less than 1.5,

wherein feeding the underflow to the third flotation cell or subsequent flotation cell in the series wherein a ratio between an available froth surface area and the pulp area (A_froth/A_pulp) comprises less than 0.45.

36. The froth flotation method according to claim 35, wherein the ratio between a height (h) from a bottom of the tank to the froth overflow lip of a froth collection launder and the diameter (D) of the tank (h/D) is less than 1.1.

37. The froth flotation method according to 35, wherein the slurry comprises copper (Cu).

38. The froth flotation method according to claim 37, wherein the slurry fed to the third flotation cell or a subsequent flotation cell in the series comprises copper (Cu) less than 0.2 weight %.