[go: up one dir, main page]

WO1999007477A1 - Tube piege - Google Patents

Tube piege Download PDF

Info

Publication number
WO1999007477A1
WO1999007477A1 PCT/SE1998/001426 SE9801426W WO9907477A1 WO 1999007477 A1 WO1999007477 A1 WO 1999007477A1 SE 9801426 W SE9801426 W SE 9801426W WO 9907477 A1 WO9907477 A1 WO 9907477A1
Authority
WO
WIPO (PCT)
Prior art keywords
liquid
hydrocyclone
pipe
outlet pipe
container
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.)
Ceased
Application number
PCT/SE1998/001426
Other languages
English (en)
Inventor
Peter Wigarthsson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Metso Fiber Karlstad AB
Original Assignee
Kvaerner Pulping AB
Kvaerner Pulping Technologies AB
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 Kvaerner Pulping AB, Kvaerner Pulping Technologies AB filed Critical Kvaerner Pulping AB
Priority to AU84701/98A priority Critical patent/AU8470198A/en
Publication of WO1999007477A1 publication Critical patent/WO1999007477A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
    • B04C—APPARATUS USING FREE VORTEX FLOW, e.g. CYCLONES
    • B04C5/00—Apparatus in which the axial direction of the vortex is reversed
    • B04C5/12—Construction of the overflow ducting, e.g. diffusing or spiral exits
    • B04C5/13—Construction of the overflow ducting, e.g. diffusing or spiral exits formed as a vortex finder and extending into the vortex chamber; Discharge from vortex finder otherwise than at the top of the cyclone; Devices for controlling the overflow
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21D—TREATMENT OF THE MATERIALS BEFORE PASSING TO THE PAPER-MAKING MACHINE
    • D21D5/00—Purification of the pulp suspension by mechanical means; Apparatus therefor
    • D21D5/18—Purification of the pulp suspension by mechanical means; Apparatus therefor with the aid of centrifugal force
    • D21D5/24—Purification of the pulp suspension by mechanical means; Apparatus therefor with the aid of centrifugal force in cyclones

Definitions

  • the invention concerns a device to decrease to content of solid contaminants in a process liquid, use of this device and a method for use of this device.
  • the production of cellulose from wood chips is done by transforming (cooking) the wood chips, suspended in a liquid under increased pressure, increased temperature and by means of chemicals, to cellulose.
  • Wood chips (treated with steam) have to be supplied to for example a continuous digester (a pressure vessel) under a considerable increase of pressure.
  • the wood chips are transported into the continuous digester among other things by means of process liquid which have been pumped to a high pressure.
  • Great increases of pressure at pumping of liquids imply the use of precision pumps which are more sensitive to solid impurities than standard pumps.
  • Other precision devices are also very sensitive to solid impurities. Consequently the content of these solid impurities in the process liquid has to be decreased in order to not damage the process equipment, not cause a too great wear on this equipment or for example cause difficulties at the pumping.
  • Known devices for removal of these impurities from the process liquids include, as a first step, one or several traps, so called hydrocyclones or vortex cleaners which separate impurities by means of gravity, centrifugal forces and sharing forces .
  • a hydrocyclone or vortex cleaner works along the following principle.
  • a liquid medium mixed with the particle is tangentially supplied into the top of the vertical cylindrical/conical or conical container, a so called hydrocyclone, and the medium gets a spirally circulating, in the beginning downwardly directed, course.
  • Particles with greater density than the liquid medium are to some extent forced by the centrifugal force out towards the jacket of the hydrocyclone and sinks gradually and are collected in a bottom cone or in a container under the bottom cone .
  • the cleaned medium comes out in the top through an outlet pipe placed in the centre of the hydrocyclone.
  • the circulation of the medium in a hydrocyclone does not merely exist at the jacket of the hydrocyclone but also the liquid in the centre of the hydrocyclone circulates. However, in the centre there exists an upwardly moving spiral of liquid. Since lighter particles will not have been completely separated at the downwardly moving spiral movement of the medium, some of these lighter particles will follow the liquid stream out of the cyclone. Accordingly the liquid will not be completely cleaned by means of the cyclone.
  • Filters require cleaning and/or regeneration which means that they preferably have to be arranged at least in pairs at continuous operation in order to allow one filter to work while the other filter is generated or cleaned.
  • This filter equipment results in capital costs in addition to costs for the cleaning work. To this can, if the occasion should arise, be added problems with the pumping of process liquids containing wood chips. Additionally, combinations of different cleaning devices often require intermediate storage vessels which results in further capital costs. Moreover known devices have some times turned out to function unsatisfying in spite of addition of filters.
  • the invention eliminates or decreases the need of filter devices for further cleaning of the process liquid, or part of the process liquid, after a hydrocyclone.
  • the invention also refers to a use of the device and a process for cleaning of a process liquid.
  • the circulation of the medium in a hydrocyclone does not stop at the jacket of the hydrocyclone but the circulation of the medium is transmitted to the centre of the hydrocyclone where it exists an upwardly moving spiral of the liquid. It is evident that particles of greater density/weight are positioned further out from the centre of the hydrocyclone than lighter particles, also in the centre of the cyclone. (Although the liquid near the centre of the hydrocyclone is cleaner than the liquid far away from the centre) .
  • the invention makes use of this state by dividing the outlet for cleaned liquid in two parts. This is achieved by arranging a further pipe within the outlet pipe for cleaned liquid, i.e. coaxially within the outlet pipe there is positioned a second outlet pipe for outlet of a second liquid fraction. Due to this partition the liquid in the inner coaxial pipe will get a higher purity regarding the content of solid particles. Accordingly the liquid passing through the annular outlet will contain particles of greater density, i.e. more particles, than the liquid passing through the inner outlet pipe.
  • the invention is particularly applicable to process liquids in the pulp industry where the solid impurities can have a broad spectrum of density with everything from mineral impurities to "impurities" in the form of fragments of wood chips.
  • the first liquid fraction can, eventually without any further cleaning, be used where the demands for purity are not so high.
  • the device according to the invention is especially advantageous when it is applied to a recirculating process, which due to leakage into the recirculating flow or feed of liquid would continuously increase its amount of impurities.
  • the invention facilitates a total integration of the arrangement which prior consisted of three different components, i.e. hydrocyclone, screening device and vessel for intermediate storage.
  • the device according to the invention can consequently bind together with a vessel for intermediate storage for cleaned liquid, for example from the inner coaxially situated outlet pipe which result in that the three components now can be made as a single device.
  • the vessel for intermediate storage can be designed in a suitable manner, for example cylindrically or as a truncated cone or in any other appropriate way.
  • the detailed design of the remaining parts of the hydrocyclone is not a main object for this invention but for example also cylindrical/conical hydrocyclone and different proportions on the hydrocyclones are possible, even if the preferred mode is a conical hydrocyclone according to the figures below.
  • Fig. 1 shows schematically a preferred device according to the invention
  • Fig. 2 shows an alternate design of a preferred device according to the invention bound together with a vessel for storage
  • Fig. 3 is a flow diagram of a part of the feeding devices of a continuous digester involvning the device according to the invention.
  • FIG. 1 there is shown a schematic design of a preferred device according the invention.
  • the conical hydrocyclone 1 is provided with a tangential inlet 2 through the upper part of its conical jacket 1A.
  • a flat lid IB at the upper part of the cyclone, since this design appears to be advantageous in connection with flowing/separation of process liquids within pulping.
  • the hydrocyclone 1 is further at the lowermost outlet 1C of the of the cone provided with a detachable container 3 in which the separated particle are collected.
  • the purified liquid is led out upwardly through an outlet pipe 4, within which a second concentric outlet pipe 5 is arranged.
  • the liquid which will be purified is supplied through inlet 2 and gets a helical movement, in the beginning there is a downwardly directed movement, in which heavier particles partially are separated in a known manner to the container 3 by means of i.a. the gravitation, centrifugal force and shearing forces. Afterwards the liquid, partially cleaned from particles, is moving upwards in the middle of the cone still in a circulating movement. The liquid finally leaves the cyclone through the outlet pipes 4 and 5.
  • all solid particles have not been separated and left down in the container 3. , but some will follow the upwardly moving swirl, especially non-dense particles, e.g. wood-chips. Nevertheless these particles will be positioned further out in the up moving swirl, due to the centrifugal force. Consequently these particles will pass out from the cyclone through the annular passage defined between the two pipes 4,5. Accordingly the liquid which is led through the inner pipe 5 will be cleaner than the liquid which is led through the outer pipe .
  • FIG. 2 there is shown a preferred integrated device according to the invention, i.e. bound together with a container 7 for cleaned liquid.
  • the outlet pipe 5 for cleaned liquid from the hydrocyclone 1 is arranged with discharge opening 6 which penetrates the wall of the outer pipe 4 enabling a discharge at about half the height of the container 7.
  • the container 7 is provided with an outlet 8 at the lowermost part of its periphery.
  • the outlet 6 of the pipe 5 is preferably situated above the outlet 8.
  • Purified liquid from the hydrocyclone is led via the pipe 5 through the entrance 6 out in the container 7.
  • the liquid from the container 7 is pushed or pumped out from the container 7 through the outlet 8, which is for example controlled by the level in the container 7.
  • the liquid passing through the annular part within the outer pipe 4 is led out through said pipe 4 at the top of the container 7, where the pipe 5 penetrates the wall off the container 7.
  • the inlet 5A of the inner pipe 5 is positioned at a distance L2 within the outer pipe 4.
  • the distance between the two inlets 4A, 5A is greater than the diameter of the outer pipe, more preferred 2>2D, in order to obtain a steady swirl at the level of the inlet 5A of the inner pipe 5.
  • the length L2 of the inner pipe 5 should exceed 5 times the diameter of the outer pipe, i.e. L1>5D, more preferred 12D>L1>8D, in order to achieve a "nice flow" out of the inner tube 5.
  • Fig. 3 shows a flow diagram with some part of the feeding devices at a continuous digester.
  • the feeding device in fig. 3 comprises a chip chute 10, a high pressure feeding device 11 (from now on called HP- feeder in the description) for transfer of the wood chips to the continuous digester (not shown) , a liquid pipe 12 and a wood chips/liquid pipe 13 discharging in the continuous digester (not shown) .
  • the feeding device also comprises a liquid pipe 2 ' , with a pump C3 and the combination of the devices described in fig. 2 completed with a pump C2.
  • the wood chips are consequently suspended with liquid, in order to make it possible for transport of the wood chips downwards in the chip chute 10, and are subsequently introduced into the HP-feeder 11.
  • the main part of the liquid used for the suspension already mentioned is separated together with a great part of its content of solid impurities in the HP- feeder 11 which can be compared to a rotary vane feeder where the wood chips are separated from some of the liquid in a first position.
  • the wood chips are transported via the pipe 13 to the continuous digester by means of the liquid supplied from high pressure pipe 12, when the compartment of the HP- feeder is rotated to that position.
  • the liquid, separated in the HP-feeder 11, is transported via pipe 2 ' by means of the pump C3 through the inlet 2 to the purification device 1 according to the invention. Accordingly, within this device heavier solid impurities are separated into the container 3 and the purified liquid is taken out as two separate fractions of which one is led through the outlet pipe 4 and the other through outlet pipe 5.
  • the less purified fraction, through the outlet pipe 4, is led back to the chip chute 10 because there the purity requirement is not exceptional high.
  • the further purified fraction is led through the outlet pipe 5, through the entrance 6 to the container 7.
  • this further purified liquid is pumped by means of the pump C2 , controlled by the level in the container 7, through the outlet 8 for use where the requirements of purity of the liquid are higher, e.g. to be mixed into the liquid in liquid pipe 12 which has a pressure of about 1 500 kPa (15 bar) .
  • inlet pipe 2 may be angled slightly downwards in order to assist in creating the downward moving swirl.
  • inlet pipe 2 may be angled slightly downwards in order to assist in creating the downward moving swirl.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Cyclones (AREA)

Abstract

L'invention concerne un dispositif de réduction de la teneur en impuretés solides d'un liquide de traitement, lequel dispositif comprend un hydrocyclone (1) pourvu d'un orifice d'entrée tangentiel (2), un contenant destiné au matières séparées (3) ainsi qu'un tuyau de sortie (4) destiné au liquide purifié, et est caractérisé en ce que ce tuyau (4) contient un autre tuyau de sortie (5), disposé de manière coaxiale et destiné à une seconde fraction liquide purifiée. En outre, l'invention concerne l'utilisation d'un tel dispositif dans la purification de liquides de traitement provenant d'un lessiveur en continu, ainsi qu'un procédé de nettoyage d'un liquide de traitement provenant de ce lessiveur.
PCT/SE1998/001426 1997-08-12 1998-07-31 Tube piege Ceased WO1999007477A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU84701/98A AU8470198A (en) 1997-08-12 1998-07-31 Tube trap

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9702913-6 1997-08-12
SE9702913A SE9702913D0 (sv) 1997-08-12 1997-08-12 Sandfång

Publications (1)

Publication Number Publication Date
WO1999007477A1 true WO1999007477A1 (fr) 1999-02-18

Family

ID=20407911

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE1998/001426 Ceased WO1999007477A1 (fr) 1997-08-12 1998-07-31 Tube piege

Country Status (3)

Country Link
AU (1) AU8470198A (fr)
SE (1) SE9702913D0 (fr)
WO (1) WO1999007477A1 (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2756878A (en) * 1952-06-10 1956-07-31 Erie Mining Co Three product wet cyclone
FR1456617A (fr) * 1965-07-22 1966-07-08 Procédé et appareil pour la séparation d'impuretés contenues dans des suspensions fibreuses
US3405803A (en) * 1963-08-26 1968-10-15 Voith Gmbh J M Vortex separator
GB2024664A (en) * 1978-07-06 1980-01-16 Oishikikai Mfg Co Apparatus for separating foreign matter from liquid papermaking material
EP0037278A2 (fr) * 1980-04-01 1981-10-07 ELAST-O-COR PRODUCTS & ENGINEERING LIMITED Section d'évacuation pour hydrocyclones avec sorties concentriques pour la fraction traitée

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2756878A (en) * 1952-06-10 1956-07-31 Erie Mining Co Three product wet cyclone
US3405803A (en) * 1963-08-26 1968-10-15 Voith Gmbh J M Vortex separator
FR1456617A (fr) * 1965-07-22 1966-07-08 Procédé et appareil pour la séparation d'impuretés contenues dans des suspensions fibreuses
GB2024664A (en) * 1978-07-06 1980-01-16 Oishikikai Mfg Co Apparatus for separating foreign matter from liquid papermaking material
EP0037278A2 (fr) * 1980-04-01 1981-10-07 ELAST-O-COR PRODUCTS & ENGINEERING LIMITED Section d'évacuation pour hydrocyclones avec sorties concentriques pour la fraction traitée

Also Published As

Publication number Publication date
SE9702913D0 (sv) 1997-08-12
AU8470198A (en) 1999-03-01

Similar Documents

Publication Publication Date Title
US3971718A (en) Hydrocyclone separator or classifier
US4578199A (en) Cyclone separators
JP3587523B2 (ja) 液体／固体分離
US6596170B2 (en) Long free vortex cylindrical telescopic separation chamber cyclone apparatus
US4696737A (en) Fiber recovery elutriating hydrocyclone
US3433362A (en) Cyclone purifier
US4309283A (en) Hydrocyclone
US3353673A (en) Apparatus for specific gravity separation of solid particles
KR20140123093A (ko) 사이클론 언더플로우에서 미세 물질을 저감시킨 하이드로사이클론
CA2473537C (fr) Systeme d'hydrocyclone a deux etages
US3425545A (en) Method and apparatus for separating fibrous suspensions
US4510056A (en) Hydrocyclone separator
US4473478A (en) Cyclone separators
FI73760B (fi) Separator foer separation av en blandning av en cellulosamassasuspension och grova, tunga partiklar.
US5535892A (en) Two stage compound spiral separator and method
JPH0229384B2 (fr)
US20050155916A1 (en) Cylindrical telescopic structure cyclone apparatus
AU595970B2 (en) Separation of granular solid material
US7997414B2 (en) Method for separating particles in hydrous slurry and a hindered-bed separator
PL161347B1 (pl) Sposób i urzadzenie do oddzielania i odzyskiwania materialu czasteczkowego PL
EP2389251B1 (fr) Procédé pour la séparation de particules dans une suspension épaisse aqueuse
US20190060918A1 (en) Cyclone system
US4783254A (en) Cyclone separator means
WO1999007477A1 (fr) Tube piege
US5186823A (en) Hydrocylone apparatus for separating dense particles from a flowing liquid

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 GM HU ID 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 SL TJ TM TR TT UA UG US UZ VN YU ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW SD SZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

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

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP

Ref document number: 1999512042

Format of ref document f/p: F

NENP Non-entry into the national phase

Ref country code: CA