EP0144421B1 - Column froth flotation - Google Patents
Column froth flotation Download PDFInfo
- Publication number
- EP0144421B1 EP0144421B1 EP84902567A EP84902567A EP0144421B1 EP 0144421 B1 EP0144421 B1 EP 0144421B1 EP 84902567 A EP84902567 A EP 84902567A EP 84902567 A EP84902567 A EP 84902567A EP 0144421 B1 EP0144421 B1 EP 0144421B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- column
- plates
- pulp
- section
- particles
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D1/00—Flotation
- B03D1/02—Froth-flotation processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D1/00—Flotation
- B03D1/08—Subsequent treatment of concentrated product
- B03D1/082—Subsequent treatment of concentrated product of the froth product, e.g. washing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D1/00—Flotation
- B03D1/14—Flotation machines
- B03D1/1481—Flotation machines with a plurality of parallel plates
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03D—FLOTATION; DIFFERENTIAL SEDIMENTATION
- B03D1/00—Flotation
- B03D1/14—Flotation machines
- B03D1/24—Pneumatic
Definitions
- This invention relates to froth flotation and, more particularly, to column froth flotation for beneficiating mineral ores and the like.
- Froth flotation has been used to beneficiate a variety of mineral ores and to effect separation of various other materials for many years.
- Froth flotation involves the separation of particles from each other in a liquid pulp based on differences in hydrophobicity. The pulp is aerated by introducing a plurality of minute air bubbles into it. The air bubbles tend to attach to the floatable (hydrophobic) particles and cause those particles to rise to the surface as a froth product which overflows from the flotation device, leaving behind the non-floatable (hydrophilic) particles.
- the air diffusers in flotation columns have a tendency to become plugged, particularly when a lime depressant is used, causing an uneven distribution of air throughout the pulp. Also, the small air bubbles generated at the bottom of the column tend to enlarge as they rise toward the top due to a change in static pressure within the column, resulting in a reduced surface contact between the air and particles.
- Several different approaches have been used to alleviate this problem, including the use of hydrophobic materials and, instead of using a diffuser, introducing the air as a fine dispersion in water. The latter approach is disclosed in US-A- 3,371,779.
- US-A- 1,809,646 discloses a device for scrubbing napthalene and analogous hydrocarbons from fuel gas.
- the device includes a column having a lower portion filled with steel turnings.
- a solvent is introduced into the column at an intermediate location and sprayed downwardly on to the steel turnings through a spray nozzle.
- the solvent is distributed over the surface of the steel turnings for contact with fuel gas flowing upwardly through the column.
- the upper portion of the column can include steel turnings.
- solvent is spread downwardly on to the steel turnings through spray nozzles in order to contact the upwardly flowing fuel gas.
- the device is a gas scrubbing device in which gas in a continuous phase is present in the lower portion of the column.
- US-A- 3,339,730 describes a conventional column froth flotation apparatus and process employing a diffuser, or bubbler, for introducing pressurized air into the lower portion of a completely unpacked column.
- An object of the invention is to provide a simple, economical froth flotation device and process capable of separating floatable particles from an aqueous pulp of a mixture of floatable and non-floatable particles with a minimum number of flotation stages.
- Another object of the invention is to provide a froth flotation device and process which produces increased air-to-particle contact.
- a further object of the invention is to provide a froth flotation device and process which requires minimal amounts of water and energy.
- a still further object of the invention is to provide a froth flotation column which does not require an air diffuser having a tendency to become plugged during operation.
- the invention provides a device for concentrating by froth flotation a floatable material in an aqueous pulp containing a mixture of floatable and non-floatable particles, said device comprising a tubular flotation column having an upper portion including a primary cleaning section, a lower portion including a scavenging section, and an intermediate portion between said cleaning and scavenging sections; means located outside of said column for conditioning an aqueous pulp containing the floatable and non-floatable particles to enhance separation of such particles by froth flotation; a pulp inlet section for introducing the aqueous pulp from said pulp conditioning means into said intermediate portion ; means for introducing wash water into said upper portion of said column above said cleaning section for downward flow; means for introducing a pressurized gas which does not react chemically under the flotation conditions into said lower portion of said column below said scavenging section; means for discharging a float fraction containing floated particles of the aqueous pulp from the upper portion of said column above said cleaning section ; and
- An aqueous pulp containing a mixture of flotable and non-floatable particles is introduced into a column.
- a gas which does not react chemically under the flotation conditions preferably air, is broken into fine bubbles as it is forced upwardly through the flow passages in the packing. These bubbles intimately contact the floatable particles and form a froth concentrate or float fraction which contains the floatable particles and overflows from the top portion of the column.
- the packing comprises a plurality of vertically spaced plates and spacer means for laterally spacing the plates apart to define a plurality of small flow passages between adjacent plates.
- the spacer means can comprise rows of corrugations on each of the plates, preferably extending diagonally relative to the horizontal.
- separate, vertically adjacent sections of the plates are provided. These sections preferably are oriented so that the vertical planes of the plates in one section are angularly related to the vertical planes of the plates in the adjacent section.
- Fig. 1 is a schematic representation of a froth flotation column embodying the invention.
- Fig. 2 is an exploded, perspective view of a portion of the corrugated plates making up one section of packing for the column illustrated in Fig. 1.
- the column flotation device and process of the invention can be used to separate a wide variety of materials in a broad range of particle sizes. It is particularly adaptable for separation of mineral values from the gangue in fine-grained ores, such as low-grade, oxidized taconite ores from the Lake Superior area.
- the invention will be described in connection with that application.
- the flotation device 10 includes a tubular column 12 having an upper portion 14 and a lower portion 16, a pulp inlet 18 for introducing a conditioned aqueous slurry or pulp of an oxidized taconite ore into the column at an intermediate location, a water inlet 20 for introducing wash water into the upper portion of the column 12, and a gas inlet 22 for introducing a pressurized gas, such as air, into the lower portion 16 of the column 12.
- a pressurized gas such as air
- the column 12 can be generally upright or vertical as illustrated in Fig. 1 or inclined at angle to the vertical.
- the column 12 is partially filled with a packing 24 which defines a large number of small flow passages extending in a circuitous or tortuous pattern between the upper and lower portions 14 and 16. Wash water introduced into the upper portion 14 of the column 12 through the water inlet 20 flows downwardly through these flow passages. Pressurized air introduced into the lower portion 16 of the column 12 through the gas inlet 22 is forced upwardly through these flow passages, countercurrently to the wash water and the portion of the aqueous pulp descending through these flow passages.
- wash water descending through the flow passages in the packing 24 induces entrained non-floatable particles to separate from the froth concentrate and drop by gravity (i.e., sink) through these flow passages.
- the wash water can be introduced into the column 12 in any convenient manner, it preferably is introduced into the froth chamber 26 and above the top surface of the froth concentrate 26 through a spray nozzle 32 centrally disposed in the top of the column 12.
- the spray nozzle 32 distributes multiple streams of water over the froth in the froth chamber 26, thereby insuring a more uniform contact of the wash water with non-floatable particles in the froth concentrate 25 and also a more uniform distribution of the wash water through the flow passages in the packing 24.
- a tailing fraction 33 containing the non-floatable particles in the aqueous pulp collects in a tailing chamber 32 at the bottom of the column 12 and is discharged therefrom through an outlet 34.
- the tailing chamber 32 preferably is conically shaped as illustrated in Fig. 1 to promote discharge of the tailing fraction.
- the tailing fraction preferably is withdrawn through the outlet 34 by a conventional variable flow pump 36.
- the column 12 can have various cross-sectional configurations, in the specific construction illustrated, it has a square cross section.
- the cross sectional dimensions and length of the column 12 are governed by the type of aqueous pulp being treated, the particular type of packing used, the desired throughput, and other variables familiar to those skilled in the art.
- the packing 24 can be in a variety of different forms capable of providing a substantially plugged flow condition and defining a large number of flow passages extending in a circuitous or tortuous pattern between the upper and lower portions of the column 12. These flow passages cause the air bubbles to break up and combine into fine bubbles of relatively uniform size, thereby maximizing intimate surface area contact with the floatable particles.
- Suitable packing includes conventional packing materials used in packed tower for vapor-liquid transfer operations, such as Raschig rings, Berl saddles, partition rings, and the like.
- the packing 24 consists of a plurality of sections 38a-38f of vertical extending plates 40.
- Each section includes a plurality of the plates 40 and spacer means for laterally spacing the plates 40 apart to define a plurality of relatively small flow passages between adjacent plates 40.
- spacer means comprises uniformly spaced rows of corrugations 42 on each plate 40.
- the corrugations 42 preferably extend diagonally, e.g., at an angle of approximately 45° to the horizontal, to eliminate vertical flow passages of substantial length.
- the angular orientation of the corrugations can be varied to control flow through the flow passage. For instance, this flow can be increased by increasing the angle of the corrugations 42 to the horizontal.
- the corrugations 42 of alternate plates 40 preferably extend in the opposite direction as illustrated in Fig. 2. That is, the corrugations on one plate extend at an angle to the corrugations on the next plate. Also, alternate sections are positioned so that the vertical planes of the plates in one section are angularly related (e.g., at about 90°) to the vertical planes of the plates in the adjacent section. Referring to Fig. 1, the vertical planes of the plates 40 in sections 38a, 38c, and 38e extend perpendicularly to the plane of the page and the vertical planes of the plates in sections 38b, 38d and 38f extend parallel to the plane of the page.
- the packing sections 38c and 38d in the vicinity of the pulp inlet 38 preferably are spaced apart to provide a substantially unobstructed feed compartment or chamber 44.
- the packing sections 38a, 38b, and 38c above the feed chamber 44 make up the primary cleaning section of the column 12 and the packing sections 38d, 38e and 38f below the feed chamber 44 make up a scavenging section wherein the floatable particles are separated from the descending tailings.
- an iron ore such as oxidized taconite
- An aqueous slurry or pulp of the particles is introduced into a stirred conditioning vessel 46 for the addition and admixing of suitable flotation reagents.
- a cationic collector or an anionic collector for calcium activated silica
- a suitable anionic collector such as a fatty acid type collector, is added to and thoroughly mixed with the aqueous pulp in the conditioning vessel 46.
- conditioning reagents can be used depending primarily on the material being treated and the type of flotation.
- the conditioning reagent disclosed in US-A- 4,132,635 which patent is incorporated herein by reference, is particularly effective for iron ores when an anionic collector is used. That conditioning reagent is formed by mixing a polyvalent metal salt with an alkali metal silicate. The conditioning reagent is usually added to and thoroughly mixed with the pulp prior to the addition of the collector. After the collector has been added to the conditioning vessel 46, the pulp is mixed for a sufficient time to insure uniform dispersion of the collector throughout the pulp.
- the frothing agent can be incorporated into the pulp before, after, or together with the collector. If the frothing agent is added separately, the pulp is mixed for a sufficient time to insure uniform dispersion of the frothing agent throughout the pulp.
- the pulp is withdrawn from the conditioning vessel 46 by a pump 48 and introduced into the column through the pulp inlet 18.
- the flow rates of the ore pulp, the air and the wash water can be adjusted to obtain a material balance which provides the most effective separation of the floatable particles (e.g., iron oxide) from the non-floatable particles (e.g., gangue).
- floatable particles e.g., iron oxide
- the device and process of the invention have several advantages over conventional flotation devices and processes. They provide all the advantages of conventional flotation columns and further provide increased air-to-particle contact, eliminate the need for a special device in the bottom of the column for generating fine air bubbles, and require less water and energy. More importantly, floatable particles, such as iron oxide, can be more effectively separated from non-floatable particles, such as gangue, with single stage flotation. That is, a conventional flotation column usually requires at least two flotation stages to recover the same amount of iron oxide from a low grade iron ore.
- the device of the invention can be used in combination with conventional flotation machines and two or more can be used in series.
- Samples of 1.68mm sieve size (-10 mesh) oxidized taconite ore were ground batchwise at 60 weight % solids in a rod mill in the presence of water for about 20 minutes to produce a slurry or pulp of about 80 weight % passing 32 microns sieve size (500 mesh).
- the pulp was conditioned with a conditioning reagent prepared in accordance with US-A- 4,132,635 and the pH was adjusted to 8.8 by adding soda or sulfuric acid.
- the resulting pulp samples were separately introduced into a stirred container where a fatty acid collector (PAMAK-4), No. 2 fuel oil, and a frothing agent were added and mixed into the pulp.
- PAMAK-4 fatty acid collector
- No. 2 fuel oil No. 2 fuel oil
- a frothing agent were added and mixed into the pulp.
- the conditioned pulp samples containing 20% solids were continuously pumped from the stirred container into the mid-section of the column at a rate of about 130 cc/min. Water was introduced near the top of the column at a flow rate of about 50 cc/min. and air was introduced near the bottom of the column at a flow rate of about 8 l/min.
- FIG. 1 A series of pilot plant tests were run on a column arranged generally in the manner illustrated in Fig. 1 and a conventional 8-stage WEMCO Fagergren flotation machine.
- the column was 6m (20 feet) tall,had a 18cm(7.25 inch) x 18cm(7.25 inch) square cross section, and included six 91cm(3 foot) sections of packing plates.
- Each packing section was packed with 5 layers of corrugated plates.
- the plate corrugations were 3.2mm(1/8 inch) high and extended at about 45 o to the horizontal, and alternate layers or sections were oriented at 90 o to each other.
- An oxidized taconite ore was ground to about 75% 32 microns sieve size (-500 mesh) and formed into a pulp.
- a conditioning reagent prepared in accordance with US-A- 4,132,635, an anionic collector (PAMAK-4), and No. 2 fuel oil were mixed into the pulp.
- One stream of the conditioned pulp containing about 20 weight % solids was pumped into the feed compartment of the column at a feed rate of about 67.5kg/hr(150 lbs/hr) and another stream of the same pulp was processed in the conventional flotation machine.
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- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Biotechnology (AREA)
- Chemical & Material Sciences (AREA)
- Dispersion Chemistry (AREA)
- Paper (AREA)
- Manufacture And Refinement Of Metals (AREA)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT84902567T ATE74541T1 (de) | 1983-06-16 | 1984-06-13 | Schaumflotation in kolonne. |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US50479383A | 1983-06-16 | 1983-06-16 | |
US504793 | 1983-06-16 |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0144421A1 EP0144421A1 (en) | 1985-06-19 |
EP0144421A4 EP0144421A4 (en) | 1988-04-26 |
EP0144421B1 true EP0144421B1 (en) | 1992-04-08 |
Family
ID=24007759
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP84902567A Expired - Lifetime EP0144421B1 (en) | 1983-06-16 | 1984-06-13 | Column froth flotation |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP0144421B1 (sv) |
AU (2) | AU561931B2 (sv) |
CA (1) | CA1210167A (sv) |
DE (1) | DE3485641D1 (sv) |
FI (1) | FI75280C (sv) |
WO (1) | WO1985000021A1 (sv) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11958062B2 (en) | 2020-04-17 | 2024-04-16 | Korea Atomic Energy Research Institute | Float sorting device for selective separation of non-metallic minerals |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4966687A (en) * | 1985-12-19 | 1990-10-30 | The Standard Oil Company | Method and apparatus for column flotation of mineral matter |
US4964576A (en) * | 1988-04-04 | 1990-10-23 | Datta Rabinder S | Method and apparatus for mineral matter separation |
GB8925833D0 (en) * | 1989-11-15 | 1990-01-04 | Robertet Sa | Derivatives of aromatic benzoates as inhibitors of esterase-producing micro-organisms |
AU629965B2 (en) * | 1990-07-30 | 1992-10-15 | Rabinder S. Datta | Method and apparatus for mineral matter separation |
DE19611864C1 (de) * | 1996-03-26 | 1997-12-11 | Voith Sulzer Stoffaufbereitung | Flotationsverfahren und Vorrichtung zur Abscheidung von Feststoff aus einer papierfaserhaltigen Suspension |
CA2455011C (en) | 2004-01-09 | 2011-04-05 | Suncor Energy Inc. | Bituminous froth inline steam injection processing |
US7510083B2 (en) | 2004-06-28 | 2009-03-31 | The Mosaic Company | Column flotation cell for enhanced recovery of minerals such as phosphates by froth flotation |
BR112015028972A2 (pt) | 2013-05-23 | 2017-07-25 | Dpsms Tecnologia E Inovacao Em Mineracao Ltda | sistema automatizado de flotação de colunas com bicos injetores aeradores e processo |
ITUB20156822A1 (it) * | 2015-12-11 | 2017-06-11 | Paolo Bozzato | Apparato e procedimento per la separazione con schiuma |
CN113275132B (zh) * | 2021-05-08 | 2023-03-07 | 武汉工程大学 | 一种磷矿反浮选的浮选柱 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2416066A (en) * | 1944-05-19 | 1947-02-18 | Donald S Phelps | Froth flotation cell |
EP0057445A2 (en) * | 1981-01-29 | 1982-08-11 | The Standard Oil Company | Apparatus and method for froth flotation separation |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1809646A (en) * | 1926-01-29 | 1931-06-09 | Koppers Co Inc | Apparatus for treating gases |
US3339730A (en) * | 1962-07-14 | 1967-09-05 | Column Flotation Co Of Canada | Froth flotation method with counter-current separation |
SE318587B (sv) * | 1964-07-10 | 1969-12-15 | C Munters |
-
1984
- 1984-05-17 AU AU28329/84A patent/AU561931B2/en not_active Ceased
- 1984-06-04 CA CA000455766A patent/CA1210167A/en not_active Expired
- 1984-06-08 FI FI842340A patent/FI75280C/sv not_active IP Right Cessation
- 1984-06-13 WO PCT/US1984/000926 patent/WO1985000021A1/en active IP Right Grant
- 1984-06-13 EP EP84902567A patent/EP0144421B1/en not_active Expired - Lifetime
- 1984-06-13 DE DE8484902567T patent/DE3485641D1/de not_active Expired - Lifetime
- 1984-06-13 AU AU31004/84A patent/AU3100484A/en not_active Abandoned
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2416066A (en) * | 1944-05-19 | 1947-02-18 | Donald S Phelps | Froth flotation cell |
EP0057445A2 (en) * | 1981-01-29 | 1982-08-11 | The Standard Oil Company | Apparatus and method for froth flotation separation |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11958062B2 (en) | 2020-04-17 | 2024-04-16 | Korea Atomic Energy Research Institute | Float sorting device for selective separation of non-metallic minerals |
Also Published As
Publication number | Publication date |
---|---|
AU2832984A (en) | 1984-12-20 |
EP0144421A4 (en) | 1988-04-26 |
FI75280C (sv) | 1988-06-09 |
AU561931B2 (en) | 1987-05-21 |
CA1210167A (en) | 1986-08-19 |
FI75280B (fi) | 1988-02-29 |
EP0144421A1 (en) | 1985-06-19 |
WO1985000021A1 (en) | 1985-01-03 |
AU3100484A (en) | 1985-01-11 |
DE3485641D1 (de) | 1992-05-14 |
FI842340A0 (fi) | 1984-06-08 |
FI842340A (fi) | 1984-12-17 |
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