WO1997047405A1 - Separation a sec des fines poudres d'un contaminant grossier dans un lit a fluide vibrant - Google Patents

Separation a sec des fines poudres d'un contaminant grossier dans un lit a fluide vibrant Download PDF

Info

Publication number
WO1997047405A1
WO1997047405A1 PCT/US1997/010232 US9710232W WO9747405A1 WO 1997047405 A1 WO1997047405 A1 WO 1997047405A1 US 9710232 W US9710232 W US 9710232W WO 9747405 A1 WO9747405 A1 WO 9747405A1
Authority
WO
WIPO (PCT)
Prior art keywords
fine powder
bed
coarse particles
coarse
particles
Prior art date
Application number
PCT/US1997/010232
Other languages
English (en)
Inventor
Larry G. Sherman
Original Assignee
Kerr-Mcgee Chemical Corporation
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Kerr-Mcgee Chemical Corporation filed Critical Kerr-Mcgee Chemical Corporation
Priority to AU33901/97A priority Critical patent/AU3390197A/en
Publication of WO1997047405A1 publication Critical patent/WO1997047405A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
    • C09C1/36—Compounds of titanium
    • C09C1/3607—Titanium dioxide
    • C09C1/3615—Physical treatment, e.g. grinding, treatment with ultrasonic vibrations
    • 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
    • B03B—SEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS
    • B03B4/00—Separating by pneumatic tables or by pneumatic jigs
    • B03B4/02—Separating by pneumatic tables or by pneumatic jigs using swinging or shaking tables
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G23/00—Compounds of titanium
    • C01G23/04—Oxides; Hydroxides
    • C01G23/047—Titanium dioxide
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G23/00—Compounds of titanium
    • C01G23/04—Oxides; Hydroxides
    • C01G23/047—Titanium dioxide
    • C01G23/0475—Purification
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/51—Particles with a specific particle size distribution
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer

Definitions

  • the present invention relates to fluidization methods and apparatus for separating compositions comprised of particles having different densities, and more particularly a method that separates fine titanium dioxide end products from coarse particulate contaminants including sand used in the production of titanium dioxide pigment.
  • the coarse particles may be introduced for several reasons.
  • the coarse particles may be introduced into the reactor in order to reduce or prevent the deposition of product titanium dioxide onto the reactor surface, to scour reactor and/or burner surfaces, or they may be introduced into the cooler to quench the reaction products, or to prevent or reduce the deposition of pigmentary titanium dioxide on the surfaces of the cooler. In each case, the pigmentary titanium dioxide must subsequently be separated from the coarse particulate material.
  • Fluidized beds often include a perforated horizontal plate through which a fluidizing medium, such as air, flows upwardly to fluidize particulate material supported on the plate. Particles of higher specific gravities tend to sink to the bottom of the bed while particles of lower specific gravity float to the top of the bed. The lighter particles rise to an elevation at which they can be elutriated or recovered by means of a larger diameter cylindrical disengaging zone, down covered tubes, and other apparatus. The separations obtained in such simple apparatus depend generally upon gross differences in particle size, shape, and density.
  • Fluidized bed devices designed to classify materials by fluidization potential are disclosed, for instance, by Matheson, US Patent No. 2,683,685; Greenwood, US Patent No. 3,825, 116; Barari, et al., US Patent No. 4,589,981; and Belk, US Patent No. 4,857, 173. Fluidized bed devices suffer from a common general problem: they generally fail to overcome the aggregative properties of fine powders, thereby frustrating attempts to classify fine powders by gaseous fluidization. Because pigmentary titanium dioxide is a fine powder, its aggregative properties' in the past frustrated attempts to separate it from coarse particles by gaseous fluidization.
  • Fine powders are known to drop to the base of fluidized beds, readily pack, and to behave as aggregates and not as individual particles.
  • prills In addition to aggregative problems further problems arise during attempted fluidization of compositions containing dry titanium dioxide particles due to the formation of what are commonly termed "prills."
  • prills There is a tremendous affinity among titanium dioxide particles in gaseous media. This particle affinity causes titanium dioxide particles to readily adhere to one another in gaseous media, and create larger, undesirable particles that frustrate effective fluidization.
  • the affinity among particles increases as their level of internal energy is raised through such action as gaseous fluidization.
  • prill formation is increased at higher fluidizing velocities. Longer classification times also result in greater prill formation due simply to the increased opportunity time for the particles to collide, adhere and form prills.
  • the primary commercial approach to separating relatively coarse particles from fine particles within a fine powder composition involves wet processing.
  • Wet processing comprises first mixing the powder composition with water to form a slurry. Once a mixture of coarse and fine particles has been slurried in water a variety of separation options are available based upon gravity, density and size of particles. Such separation methods include, without limitation, sedimentation, wet screening, hydrocloning, and filtration. Although these approaches are individually rather simple, one is forced to handle large volumes of dilute slurry, which can lead to large volumes of waste water. Ultimately, one must still produce a dry fine powder of the desired particle size.
  • Claridge, et al. British Patent Specification No. 1,098,881 disclose an improved gaseous fluidization device wherein the fluidization column supports two layered phases of fluidized particles, the lower phase a coarse particulate dense phase, the upper phase a fine powder light phase.
  • the device disclosed by Claridge et al. is capable of separating coarse particles with a typical size range of from 500 to 2,000 microns, from titanium dioxide pigment having a typical size range of from 5 to 20 microns.
  • the device disclosed by Claridge et al. suffers from its inability to separate coarse particles that are smaller than 500 to 2,000 microns from pigmentary titanium dioxide.
  • Coarse particulates in a size range of from 50 to 700 microns are often employed today in the manufacture of titanium dioxide pigment.
  • product purity specifications typically dictate that virtually all particulate impurities be removed from the finished product.
  • Dry classification devices other than fluidized bed apparatus are disclosed by, for instance, Kanda, et al., Patent No. 4,802,977 (inertial separation); Masuda, Patent No. 4,545,897 (mechanical separation by size); Schurr, et al., Patent No. 4,083,946 (injection of powder into gas traveling at supersonic velocity); and Gebauer, Patent No. 3,441, 131 (zigzag classification).
  • Kanda, et al. Patent No. 4,802,977
  • Masuda Patent No. 4,545,897
  • mechanical separation by size mechanical separation by size
  • Schurr, et al. Patent No. 4,083,946
  • Gebauer Patent No. 3,441, 131
  • the present invention is a novel solution for separating a fine powder composition which contains both coarse particles and fine powders incorporating gaseous fluidization principles.
  • a fluid bed can be operated to overcome the foregoing gaseous fluidization limitations, and effectively separate fine powders from coarse particles.
  • the process of this invention provides that initially a fine powder composition containing coarse particles is introduced to a shallow bed of the same or similar fine powder and coarse particles in which the fine powder is minimally fluidized by a fluidizing gas introduced beneath the bed.
  • a means to impart energy is provided, which energizes the fine powder composition and causes refluidization thereof. It has been surprisingly found that vibration in conjunction with minimal gaseous fluidization of the fine powder composition overcomes the aggregative properties inherent to fine powders. The coarse particles settle to the base of the bed for collection and separation from the fine powders.
  • the fine powders within the fine powder composition can be separated from coarse, undesirable particles, while the coarse particles may be concurrently withdrawn from the fluidization bed by any known withdrawing means.
  • the invention can be operated on either a batch or continuous basis.
  • Figure 1 represents a fluidizing device that can be used to carry out the process of this invention.
  • Figure 2 represents a second fluidizing device that can be used to carry out the process of this invention.
  • FIG. 1 depicts a vibrating fluid bed unit (11) configured generally as an elongated hollow vessel.
  • the general cross-sectional shape and configuration is not generally critical to the practice of the invention, provided the base of the cross-sectional area is flat and horizontal.
  • a vibrating gas distributor (13) is located at the base of the unit into which unprocessed pigment to be classified is charged through charge point (12).
  • a perforated plate (24) is formed on the upper side of the vibrating gas distributor (13).
  • the fine powder composition upon charge to the unit (11), forms a bed of powder composition (18) supported by the vibrating gas distributor (13).
  • Gas is introduced to the unit through aperture (16), whereupon the gas flows through the perforated plate (24) and the bed (18) to minimally fluidize the bed of powder composition (18).
  • As the bed of powder composition is minimally fluidized it is also vibrated in such a fashion that assists in separating the fine powders and coarse particles.
  • the vibrational energy can also be applied in such a fashion to cause the powder composition to travel through and to the end of the vessel.
  • the powder composition is thereby subjected to concurrent gaseous fluidization and vibration during its traversal along the length of the vessel. By these concurrent actions the fine powder rises above the coarse particles, and is readily separated from the coarse particles at the end of the processing vessel.
  • Sand is used to scour burners in the commercial production of TiO 2 pigments.
  • the sand must be separated from the pigment before final finishing. This is conventionally carried out via wet processing.
  • gravity/density/size separation options are available (e.g. sedimentation, wet screening, hydrocloning, and filtration).
  • gas supplied beneath fine powder does not cause all the powder to disaggregate and fluidize. Rather, rat-holes and bridges form that allow the fluidized gas to by-pass the powder.
  • energy is imparted to disaggregate the fine powder composition. Once the fine powder composition has disaggregated, the flow of fluidizing gas through the bed then causes the fine powder to fluidize and separate from the coarse particles, whereupon the fine powder can be recovered.
  • the fluidization of the powder is preferably practiced under minimal conditions. Operating at minimally fluidizing conditions serves at least two important functions:
  • fluidization will preferably be conducted such that the fine powder layer of the bed merely bubbles under the action of the minimally fluidizing gaseous flow.
  • the vibrational energy is applied to the bed in an oscillating mode to cause the bed to continuously migrate from the point where it is introduced to the unit, to the second end of the unit where the fine powder can be physically separated from the coarse particles.
  • the speed with which the bed migrates can be varied by adjustment to the vibration angle, stroke, and frequency of the vibrating mechanism. Suitable vibrating mechanisms are well known in the art.
  • vibrational energy to cause the powder composition to migrate serves several important functions. For instance, the distance of travel, or the time of travel, each influence the degree to which the fine powder and coarse particles separate into two distinct phases. By manipulating the distance of travel, or the time of travel, obtaining the maximum separation into phases of the fine powder and the coarse particles is possible before the fine powder is physically separated and drawn from the unit.
  • the migration of the powder composition also assists the physical separation of the fine powder from the coarse particles.
  • the invention is practiced in a unit
  • the bed (18) is caused to migrate from end (21) to end (23) of the unit. At end (23) the bed is caused to bump up against an overflow weir (19). As the bed migrates from end (21) to end (23) it causes the upper fine powder phase (14) of the bed (18) to flow over the weir whereupon the fine powder is separated, discharged through pipe (22) and captured by means not shown.
  • the coarse particle phase is withdrawn from the unit (1 1) through catchment duct (17) and valve assembly (20).
  • the fluidizing gas may be withdrawn from unit (11) through aperture (25).
  • fine powder composition In a batchwise mode, a charge of the fine powder composition is placed in the separator unit and gas flow and vibration operation carried out until the desired efficiency of separation has been achieved. The fine powder and coarse particle layers are then withdrawn. Another charge is then fed to the separator unit and the process repeated.
  • fine powder composition In a continuous mode of operation, fine powder composition may be added to a separator unit at a rate such that the desired efficiency of separation will be achieved.
  • a slip stream may be continuously withdrawn near the base of the bed and screened or otherwise treated to recover the coarse particles.
  • oscillating vibrational energy is employed, because such energy causes the fine powder composition to migrate in a predetermined fashion
  • energy can be imparted to the fine powder composition by other means, if in practicing the invention it is unnecessary or not possible to migrate the bed in a particular direction.
  • the bed can be mechanically shaken by a mechanical vibrator affixed to the exterior of the column, or a mechanical vibrator may be inserted directly into the bed within the column.
  • sound waves or subsonic energy waves may be transmitted directly to the fine powder composition to impart energy thereto. Any of the foregoing types of energy is sufficient, if imparted correctly, to practice the present invention, and to cause separation of fine powder from coarse particles.
  • the fluidizing gas may be introduced into the vessel in any manner provided it passes through the fine powder composition bed and gives satisfactory fluidization thereof.
  • the vessel is preferably provided with a perforated floor along its entire length through which the fluidizing gas is introduced.
  • any gas inert to the fine powder composition may be employed as the gaseous medium.
  • the term "inert gas” is used herein to mean a gas that, under the conditions prevailing within the separation vessel, is chemically inert with respect to the substances present in the vessel.
  • the term "inert gas” excludes halogens.
  • the inert gas used in the separation of titanium dioxide powder from coarse particle sand is nitrogen.
  • the principal feature of fine powders that are capable of separation from coarse particles according to this invention is their potential to separate upon fluidization into fine powder and coarse particulate.
  • the potential of the fine powder composition to separate in a fluidized bed is influenced by the relative fluidization potentials of the fine powder and the coarse particles, which are generally determined by three dependent factors — particle shape, size, and density. Of these three factors, particle size is generally the determinative characteristic. Because the process of the invention is preferably carried out under minimal fluidizing conditions, the process is capable of separating particles having minimal difference in size.
  • Fine powder compositions advantageously separated according to the process of this invention contain a fine powder component comprising particles which behave as a single entity, which single entity component has an effective size ranging from about 0.1 to about 20 microns in diameter.
  • the invention can advantageously be practiced on Ti0 2 powder components having effective sizes ranging from about 0.5 to about 10 microns in diameter.
  • the invention is most effective at separating Ti0 2 components having effective sizes from about 2 to about 5 microns in diameter.
  • the sizes refer to the titanium dioxide powder components or particles that behave as single entities within the fluidized bed, and not to the individual pigmentary particles of which they are comprised. The latter are typically from about 0.15 to about 0.2 microns in diameter.
  • the term "coarse particle” is used herein to describe a particulate material that, under the conditions prevailing within the vessel, is chemically inert with respect to any of the substances in the vessel, and has a particle density greater than the particle density of Ti0 2 .
  • the coarse particles consist of zircon particles or silica sand.
  • the coarse material may also consist of a mixture of these particulate materials.
  • the particle size range for the coarse particles is from about 50 to about 700 microns.
  • the preferred size range for the diameters of the titanium dioxide powder in the bed is from about 5 to about 20 microns.
  • the fine powder withdrawn from the second or upper fluidized layer in the bed may contain some coarse particulate material, and the coarse particulate withdrawn from the first or lower layer in the bed will contain some titanium dioxide powder, in which case further separation may be desirable. Further separation may be accomplished by any known conventional means, including those methods discussed in the background section of this specification, or introduction to a second vibrating fluidization for additional processing according to the process of this invention. Coarse particles thus separated may advantageously be recycled, by reintroduction to the reactor and/or cooler from which the coarse particles were originally withdrawn.
  • Figure 2 shows an upright hollow column (31) that constricts toward the base of the column in the shape of a cone (32).
  • a vertically inclined tube (33) is positioned within the column through which a fine powder composition stream (34) is supplied downwardly into the column.
  • a bed of coarse particles (35) separated from the fine powder (36) is shown resting within the conical base of the column (32).
  • a fluidizing gas stream (37) is injected vertically upwards into the column through the base beneath the bed of non- fluidized coarse particles (35), through the bed of non-fluidized coarse particles, and into the fine powder composition, or charge from tube (33), concurrently with said charge.
  • a portion of the fine powder composition thereby rises to the top of the column with the gas flow, and overflows the rim of the column (31).
  • the fluidizing gas is introduced to the column at such a rate that the coarse particles within the fine powder composition or raw feed are not fluidized, but rather drop into the bed of non-fluidized coarse particles.
  • the coarse particles are then periodically or continuously withdrawn from the bed by a withdrawing device (38) to prevent the volume of coarse particles from reaching a predetermined level.
  • EXAMPLE 1 A four-inch cylinder Pyrex glass tube was attached to a Pyrex glass funnel to serve as a separator vessel. There was no frit at the base of the cylinder. The cylinder was clamped in a ring stand and a vibrator having adjustable vibration amplitude was clamped to the ring stand. A nitrogen source was connected to the funnel and the gas flow was adjusted such that the open- tube superficial gas velocity was approximately 0.025 ft/sec. The vibrator was turned on and adjusted such that the amplitude was 80% of maximum. The vessel was filled with a Ti0 2 pigment which contained approximately 50% by weight of 30 mesh (100% greater than 700 microns) sand. The fluidization was initially non-uniform ("spouting").
  • the sand was visually seen to settle into the cone of the separator, where it served as a gas distributor. Once this occurred, smooth fluidization was observed. Unseparated raw TiO 2 pigment was fed into the center of the tube through a one-inch Pyrex glass standpipe which discharged approximately 1 inch below the surface of the bed. The feed rate was adjusted to approximately 3 lb/hr. Purified product cascaded over the edge of the funnel into a catch pan positioned below the funnel. The sand level in the cylinder was monitored visually. When the level of sand was about 1 inch below the rim of the cylinder, the separator was shut down and the nitrogen source disconnected from the base of the funnel. Byproduct sand was removed to reduce the level in the separator. The nitrogen source was then reconnected and separation operations were resumed.
  • EXAMPLE 2 Approximately 10 pounds of a different specification raw TiO 2 pigment was separated using the same procedure set forth in Example 1. Analysis of the feed showed 19.23% of 30 mesh sand. Analysis of the purified product showed it to be sand-free. The sand byproduct was assumed to be similar to that seen in Example 1. Material balance indicates 100% sand removal with 97% recovery of Ti0 2 as purified product.
  • Example 3 The procedure of Example 1 was used to conduct a separation of commercial raw TiO 2 pigment containing 1.5 wt% sand.
  • the conical base of the separator was filled with 30-mesh coarse sand which served as a gas distributor.
  • the 2.5 "-long cylindrical body of the separator was filled with 146.7 gm. of raw TiO 2 pigment.
  • Nitrogen was fed to the bed at a rate corresponding to 0.12 ft/sec superficial velocity, and the vibrator was adjusted to 55% of maximum.
  • Raw pigment was fed to the system at 8.1 gm/min. 88.3% of the pigment fed was recovered as purified product containing 0.29 wt%sand. Consequently, 80.7% of the sand was removed.
  • a sample of the raw feed was washed to remove the pigment and isolate the sand for screen analysis.
  • the sand from the feed was passed through a set of standard U.S. Screens to produce the following analysis:

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Inorganic Chemistry (AREA)
  • Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)

Abstract

Cette invention se rapporte à un procédé qui permet de séparer les particules grossières contenues dans une composition de fines poudres (18), ce procédé consistant: à former un système dans lequel une source d'une composition de fines poudres (18) contenant des particules grossières et des fines poudres communique avec un lit à fluidisation minimale de cette composition à l'intérieur dudit système; à acheminer depuis cette source (25) ladite composition jusqu'audit lit; à imprimer une énergie vibratoire dans ledit lit; à acheminer un gaz fluidisant (13) vers ledit lit à une vitesse propre à amener les fines poudres et les particules grossières de ladite composition de fines poudres (18) à se séparer en une phase de fines poudres (14) et une phase de particules grossières (15); à retirer les fines poudres dudit système; et à retirer les particules grossières dudit système.
PCT/US1997/010232 1996-05-29 1997-05-29 Separation a sec des fines poudres d'un contaminant grossier dans un lit a fluide vibrant WO1997047405A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU33901/97A AU3390197A (en) 1996-05-29 1997-05-29 Dry separation of fine powder from coarse contaminant in a vibrating fluid bed

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US65511796A 1996-05-29 1996-05-29
US08/655,117 1996-05-29

Publications (1)

Publication Number Publication Date
WO1997047405A1 true WO1997047405A1 (fr) 1997-12-18

Family

ID=24627598

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1997/010232 WO1997047405A1 (fr) 1996-05-29 1997-05-29 Separation a sec des fines poudres d'un contaminant grossier dans un lit a fluide vibrant

Country Status (2)

Country Link
AU (1) AU3390197A (fr)
WO (1) WO1997047405A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003028877A1 (fr) * 2001-10-04 2003-04-10 The University Of Nottingham Separation de materiaux constitues de particules fines

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE532388C (de) * 1931-08-27 Carlshuette Akt Ges Fuer Eisen Luftsetzmaschine zum Trennen von Kohlen und sonstigen Mineralien mit einer Gruppe von mehreren Pulskoerpern
DE607286C (de) * 1934-12-20 Hans Heidenreich Dr Ing Setzverfahren und Setzvorrichtung zur Trennung von koernigen Stoffen nach dem spezifischen Gewicht
DE628060C (de) * 1929-05-19 1936-03-27 Carlshuette Act Ges Fuer Eisen Luftsetzmaschine zur Aufbereitung von Kohlen und sonstigen Mineralien
US2903132A (en) * 1955-05-07 1959-09-08 Berry Paul Apparatus for sorting solid products by density
US4546552A (en) * 1982-02-02 1985-10-15 Exxon Research And Engineering Co. Fluid induced transverse flow magnetically stabilized fluidized bed
US4741443A (en) * 1985-01-08 1988-05-03 Aluminium Pechiney Fluidized bed for continuous separation of two mixed solid phases
US5047387A (en) * 1988-01-19 1991-09-10 The United States Of America As Represented By The Secretary Of The Navy Method for the selecting superconducting powders
US5299694A (en) * 1990-12-26 1994-04-05 Aluminum Pechiney Apparatus and process for separating a material in fluidized bed form and the detection of clogging

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE532388C (de) * 1931-08-27 Carlshuette Akt Ges Fuer Eisen Luftsetzmaschine zum Trennen von Kohlen und sonstigen Mineralien mit einer Gruppe von mehreren Pulskoerpern
DE607286C (de) * 1934-12-20 Hans Heidenreich Dr Ing Setzverfahren und Setzvorrichtung zur Trennung von koernigen Stoffen nach dem spezifischen Gewicht
DE628060C (de) * 1929-05-19 1936-03-27 Carlshuette Act Ges Fuer Eisen Luftsetzmaschine zur Aufbereitung von Kohlen und sonstigen Mineralien
US2903132A (en) * 1955-05-07 1959-09-08 Berry Paul Apparatus for sorting solid products by density
US4546552A (en) * 1982-02-02 1985-10-15 Exxon Research And Engineering Co. Fluid induced transverse flow magnetically stabilized fluidized bed
US4741443A (en) * 1985-01-08 1988-05-03 Aluminium Pechiney Fluidized bed for continuous separation of two mixed solid phases
US5047387A (en) * 1988-01-19 1991-09-10 The United States Of America As Represented By The Secretary Of The Navy Method for the selecting superconducting powders
US5299694A (en) * 1990-12-26 1994-04-05 Aluminum Pechiney Apparatus and process for separating a material in fluidized bed form and the detection of clogging

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003028877A1 (fr) * 2001-10-04 2003-04-10 The University Of Nottingham Separation de materiaux constitues de particules fines
US7533775B2 (en) 2001-10-04 2009-05-19 The University Of Nottingham Separation of fine granular materials

Also Published As

Publication number Publication date
AU3390197A (en) 1998-01-07

Similar Documents

Publication Publication Date Title
EP0948410B1 (fr) Procedes et appareil destines a la transformation et au traitement de matieres particulaires
Falconer Gravity separation: old technique/new methods
US4282088A (en) Process for cleaning fine coal
US2683685A (en) Elutriation of finely divided solids
US5947299A (en) Hydraulic reactor and classifier for solid particles with ultrasonic application
US2910424A (en) Separation and recovery of oil from oil sands
US4773189A (en) Separation system for polymeric blast media
ZA200106365B (en) A reflux classifier.
US4827678A (en) Separation system for polymeric blast media
USRE29625E (en) Process and apparatus for separating sand from botanical materials
US3878091A (en) Method for pneumatic classification and a pneumatic classifier
EP0680455B1 (fr) Procédé de CLASSIFICATion DE PARTICULES FINES
JPH10505782A (ja) 固体粒子の重力分離装置および方法
US5669509A (en) Dry separation of fine powder from coarse contaminant in a vibrating fluid bed
WO1997047405A1 (fr) Separation a sec des fines poudres d'un contaminant grossier dans un lit a fluide vibrant
US3485365A (en) Hydraulic upflow classification apparatus
US4455156A (en) Process for improving the gas separation in liquid/gas reactors
US1629182A (en) Whirlpool classifier and classifying process
US3105040A (en) Method and apparatus for separating intermixed divided materials
US4822482A (en) Hydraulic separating apparatus and method
KR20030085505A (ko) 건식 분리 방법 및 분리 장치
US2966431A (en) Separation of filter material from carbon black
US5361910A (en) Modified mineral jig
US4857177A (en) Dry separation of solids
AU2004201466A1 (en) A dry separation method and a separation apparatus

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE GH HU IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK TJ TM TR TT UA UG UZ VN AM AZ BY KG KZ MD RU TJ TM

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH KE LS MW SD SZ UG AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF

121 Ep: the epo has been informed by wipo that ep was designated in this application
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

NENP Non-entry into the national phase

Ref country code: JP

Ref document number: 98501830

Format of ref document f/p: F

NENP Non-entry into the national phase

Ref country code: CA

122 Ep: pct application non-entry in european phase