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EP0138475A2 - Traitement des rejets dans les cyclones et autres dispositifs séparateurs - Google Patents

Traitement des rejets dans les cyclones et autres dispositifs séparateurs Download PDF

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Publication number
EP0138475A2
EP0138475A2 EP84306608A EP84306608A EP0138475A2 EP 0138475 A2 EP0138475 A2 EP 0138475A2 EP 84306608 A EP84306608 A EP 84306608A EP 84306608 A EP84306608 A EP 84306608A EP 0138475 A2 EP0138475 A2 EP 0138475A2
Authority
EP
European Patent Office
Prior art keywords
rejects
outlet
liquid
chamber
separator
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.)
Withdrawn
Application number
EP84306608A
Other languages
German (de)
English (en)
Inventor
Graham Blakeley Chivrall
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.)
Beloit Corp
Original Assignee
Beloit Corp
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 Beloit Corp filed Critical Beloit Corp
Publication of EP0138475A2 publication Critical patent/EP0138475A2/fr
Withdrawn legal-status Critical Current

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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
    • B03B—SEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS
    • B03B11/00—Feed or discharge devices integral with washing or wet-separating equipment
    • 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
    • B04C11/00—Accessories, e.g. safety or control devices, not otherwise provided for, e.g. regulators, valves in inlet or overflow ducting
    • 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
    • B04C5/14—Construction of the underflow ducting; Apex constructions; Discharge arrangements ; discharge through sidewall provided with a few slits or perforations
    • B04C5/18—Construction of the underflow ducting; Apex constructions; Discharge arrangements ; discharge through sidewall provided with a few slits or perforations with auxiliary fluid assisting discharge
    • 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
    • B04C9/00—Combinations with other devices, e.g. fans, expansion chambers, diffusors, water locks
    • 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 present invention relates to a method and apparatus for use in separating a liquid into accepts and rejects to thereby remove heavy or light contaminants from the liquid.
  • the liquid may be a slurry of fibre and liquid and the contaminants may be droplets or fibres or other particles may be lighter or heavier than the liquid.
  • Cyclones are commonly employed to separate such contaminants from a liquid.
  • a slurry of paper fibres and water enters a conical separator, usually with its apex lower-most, by way of an inlet disposed remote from the apex.
  • a vortex is formed within the conical chamber of the separator and heavy contaminant particles migrate to the wall of the cone and proceed downwards to the apex to be ejected from an outlet, together with a proportion of good paper fibre.
  • the majority of fibre and water, substantially free from heavy contamination passes out of an axially disposed outlet passage disposed at the inlet end of the cone and opposite the apex.
  • the fibre and water emerging from either outlet may be directed into a second chamber to undergo a further separation stage. It is also possible to remove a light fraction of the contaminants by employing an axial outlet pipe disposed co-axially, within the aforementioned water and fibre outlet, or at the apex co-axially with the apex orifice.
  • the present invention aims to provide a means of minimising fibre loss in hydro-cyclones and/ or other separator devices with similar reject arrangements.
  • a method of separating a liquid into accepts and rejects utilising a separator having an outlet for the rejects, which outlet opens into a rejects chamber, the method comprising feeding the liquid to be subject to the separation into the separator, passing a further liquid through the rejects chamber to carry away rejects passing through the rejects outlet from the separator, and controlling the liquid passing through the rejects chamber to thereby control the flow of liquid through the rejects outlet so as to prevent or substantially prevent the passage of accepts therethrough whilst allowing the passage of rejects therethrough.
  • it is the pressure of the liquid flowing through the rejects chamber which is controlled, whilst according to another embodiment, it is the flow of liquid through the rejects chamber which is controlled.
  • the rejects chamber forms part of a rejects loop which comprises a pump for circulating liquid round the loop and providing pressure in the rejects chamber, valves for controlling the flow rate of liquid in the loop and the pressure thereof, auxiliary separating means for removing contaminants from the liquid, and means for replacing any liquid removed, from the loop.
  • the method can be employed in the removal of heavy or light rejects. That is to say, the reject loop may be applied to a lights outlet or to a heavies outlet. Thus, the contamination separated by the method may be heavies or lights according to the application.
  • a method of separating heavy contaminants from a fibre and liquid slurry comprising passing the slurry to be decontaminated into a separator having an outlet for the heavy particles (rejects) which opens into a rejects chamber, passing liquid through the rejects chamber in order to carry away rejects falling through the opening, and controlling the flow of liquid through the reject chamber so that there is no or virtually no flow of liquid through the opening between the separator and reject chamber.
  • More specifically one or more valves are set to control the pressure of the liquid flowing through the reject chamber in preference to controlling the flow.
  • apparatus for controlling the passage of liquid through a rejects outlet of a separator for separating a liquid into accepts and rejects, the rejects outlet opening into a rejects chamber, means for passing a further liquid through the rejects chamber to carry away the rejects passing through the rejects outlet, and means controlling the liquid passing through the rejects chamber to thereby control the flow of liquid through the rejects outlet so as to prevent or substantially prevent the passage of accepts therethrough whilst allowing the passage of rejects therethrough.
  • the means for passing the further liquid through the rejects chamber and the means controlling the liquid passing therethrough comprises inlet and outlet passages of a reject loop, a pump and respective valves.
  • the pressure in the reject chamber can be controlled to thereby control passage of the accepts and rejects from the separator.
  • apparatus for controlling the passage of liquid through the rejects outlet of a separator which apparatus comprises a passage or chamber into which the outlet opens and through which passage, liquid flows to carry away rejects falling through the opening, the flow of liquid through the passage being controlled such that there is substantially no flow of fibre and liquid slurry through the opening from the separator.
  • the apparatus is particularly suitable for use with a cyclone separator but it may be used with any other separator having a similar reject arrangement.
  • the apparatus is provided with means for controlling the pressure in the passage or chamber at the opening.
  • the means comprises one or more valves in a circuit defining a rejects loop and incorporating the rejects chamber.
  • the reject loop is preferably provided with its own auxiliary separator for removing contaminants franhe liquid in the rejects loop.
  • the apparatus may be employed in the removal of heavy or light contaminants, with the rejects chamber positioned appropriately in each case i.e. at the lights outlet or at the heavies outlet.
  • the rejects chamber is cylindrical in shape and coaxial with the rejects outlet of the separator.
  • the inlet and outlet to the rejects chamber intersects the chamber tangentially or chordally and substantially at right angles to the axis of the separator outlet.
  • the rejects chamber comprises a tubular passage whose axis is disposed at right angles to the axis of the rejects outlet.
  • the invention also contemplates apparatus for separating a liquid into accepts and rejects comprising a separator device having an __inlet for the liquid which is to be subject to the separation, means producing a flow through the device with the rejects migrating to at least one outlet, and the accepts being recovered at another outlet, the at least one outlet for the rejects opening into a or a respective rejects passage or chamber, means passing a further liquid through the rejects chamber to carry away the rejects passing through the rejects outlet, and means controlling the liquid passing through the rejects chamber to thereby control the flow of liquid through the rejects outlet so as to prevent or substantially prevent the passage of accepts therethrough whilst allowing the passage of rejects therethrough.
  • the pressure of the liquid flowing through the rejects chamber is controlled.
  • the flow of liquid through the rejects chamber is controlled.
  • apparatus for removing heavy contamination from a fibre and liquid slurry comprising a separator device having an inlet for the fibre and liquid slurry, means producing a flow through the device with the heavy contaminants migrating to an outlet, and the fibre and liquid slurry substantially free from heavy contaminants being recovered at another outlet, the outlet for the repots opening into a passage or chamber through which liquid flows to carry away the rejects which fall through the opening, the flow of liquid through the passage or chamber being controlled such that there is substantially no flow of fibre and liquid slurry through the opening.
  • the rejects chamber is preferably part of a rejects loop incorporating a pump and valves for circulating liquid round the loop and controlling the pressure and/or flow of the liquid.
  • the rejects outlet is preferably disposed downwardly of the inlet and the heavy contaminants fall through the rejects outlet opening into the rejects chamber.
  • the apparatus is for removing light contaminants the arrangement is inverted and the contaminants float upwardly to the reject outlet.
  • the separator is designed to remove both heavy and light contaminants, for example a reverse vortex separator for heavies removal followed downstream by a Uniflow cleaner for lights removal, two outlets are provided at opposite, upper and lower ends of the apparatus, each leading to a respective lights reject chamber and a heavies reject chamber.
  • valves are employed to control the flow and pressure of the liquid passing through the rejects chamber and this may be controlled automatically by providing sensors measuring the flow or pressure characteristics or the volume of liquid in the rejects loop and comparing the measured values with desired values.
  • a separator in the form of a cyclone separator is shown at 1.
  • the separator is conical with its apex lowermost and has an outlet 8 at the apex 5.
  • An inlet is shown at 2 and another outlet at 6.
  • the orifice 8 opens into a cylindrical chamber 7 which is disposed coaxially with respect to the axis of the conical separator 1.
  • the chamber 7 is provided with an inlet passage 10 and an outlet passage 9.
  • the inlet and outlet passages intersect tangentially or chordally with the chamber 7.
  • the chamber 7 forms part of a rejects loop one example of which is shown in Figure 3.
  • Figure 2c shows an alternative construction in which the passages 9,10 serve as the chamber 7. That is to say the chamber 7 is tubular, rather than cylindrical, and is disposed with its axis at right angles to the axis of the opening, which axes intersect with one another.
  • the separator 1 operates on the reverse vortex principle that is to say the contaminated paper fibre and liquid slurry enter the separator by way of the inlet 2 and a downwardly spiralling vortex is generated within the separator which causes the heavies to migrate to the wall 4 of the separator and proceed downwards to the apex 5.
  • the fibre and liquid substantially free of heavies move upwardly and emerge from the outlet 6.
  • the present invention provides a means of recovering the heavies whilst preventing the removal of fibre and water from the outlet opening 8. This is achieved by passing liquid through the rejects chamber in a controlled manner such that any tendency for the liquid in the separator to pass out of the opening is countered by the pressure exerted by the liquid flowing in the loop. In practice this is achieved by adjusting the flow rate and pressure of the liquid in the rejects loop. Valves 11,12 and 20 are provided for this purpose.
  • the circuit comprises:- a tank 14 containing a suitable liquid such as water; a pump 15 for circulating the water round the circuit; and an auxiliary separator 16 for removing in this example heavies from the water in the circuit of the rejects loop.
  • the outlet 9 from the rejects chamber incorporates valves 12 and 20 and leads to the tank 14.
  • the inlet 10 to the rejects chamber feeds from the tank 14 by way of the auxiliary separator 16 and, valves 11 and 17 are provided to control the flow rate.
  • the pressure value is set by the valve 20.
  • the system may be set up as described hereinbelow for which purpose reference is made to the pressure in the rejects chamber as measured by the pressure gauge 13.
  • Valves 11 and 12 are closed and the conical separator 1 operated under its normal conditions. There will be flow through the orifices 6 and 2 but not into chamber 7.
  • the pressure P R is recorded.
  • Valves 18 and 19 are then closed and valves 11, 12 and 20 opened.
  • Pump 15 is started and the setting of valve 20 is adjusted so that the value of P R is the same as recorded previously but with a substantial flow round the rejects loop.
  • the pump can then be stopped. Having set the valves and pressures the complete system can be operated.
  • the reject loop pump is started and shortly afterwards the conical separator pump is started, valves 18, 19, 11 and 12 having been opened, and valve 20 having been left at the setting achieved as above.
  • a level control device consisting of sensor 25, control unit 26, and motorized valve 20 controls the pressure P R in chamber 7 such that there is no flow through the orifice 8.
  • valve 20 As an increase in level 24 demands the'closure of valve 20 the system is exactly the same as an ordinary level control.
  • a by-pass balve, 31 has been found useful in setting up experiments. In trials using automatic level control of valve 20 it enables the valve always to be oscillating about its mid-position under normal operating conditions, and it also serves to ensure that the reject loop is never closed. This protects the system from full pump pressure if the valve becomes closed due to system instability or operator error.
  • a by-pass valve 31 is likewise included in the arrangement shown in Figs. 5 and 6.
  • An alternative control system requires a microprocessor (27) programmed with the known balanced pressures PAPF and PR ( Figure 5) which controls P R by adjusting valve 20.
  • a further method would be to add a short parallel or conical extension below orifice 8 (Figure 6), 29 and monitor the interface 30 between rejects loop water, which is substantially clear and stock in the separator which is substantially cloudy.
  • the rejects loop could be loaded with some tracer material to sharpen the interface.
  • Dye was used in the transparent version.
  • Production versions could use magnetic, optical, ultrasonic, radioactive, visual or other sensing at 28.
  • the sensor 28 could also be a small flowmeter. By whatever means the sensor passes a signal to control 27 which regulates pressure P R by operating valve 20 in order to prevent substantial flow through orifice 8.
  • FIGs 7a and 7b there are shown apparatus for use in removing "lights" contamination from a liquid, such as a fibre and liquid slurry.
  • a liquid such as a fibre and liquid slurry.
  • Such lights contamination may be plastics material or oil particles.
  • the apparatus of Figure 7a comprises a separator chamber 35 having an inlet 2' for the liquid to be cleaned, an outlet 37 for the lights rejects and an outlet 39 for the decontaminated liquid.
  • the outlet 37 for the lights rejects leads into a rejects chamber 41 which may have a configuration corresponding to the arrangements described in Figures 2a,2b or 2c.
  • the separator is of the Uniflow direction type.
  • the lights removal apparatus is the arrangement of Figure 1 inverted and the integers of the rejects loop correspond to those described with reference to Figure 3, with corresponding valves 11', 12' and 20' for controlling the pressure and flow in the rejects chamber 41.
  • a cleaner 16' is also provided for cleaning the liquid in the rejects loop. This comprises a light rejects removal apparatus.
  • the other integers of the apparatus are identified with reference numbers corresponding to those used in Figures 1, 2 and 3.
  • the apparatus of Figure 7b likewise comprises a separator, identified as 35" and has an inlet 2" for the liquid to be cleaned, an outlet 37" for the lights rejects and an outlet 39" for the decontaminated liquid.
  • the separator is conical with the outlet 39" lowermost at the apex, and the inlet 2" and the outlet 37" at the other end.
  • the outlet 37" feeds into a rejects chamber 41".
  • the rejects chamber 41" is part of a rejects loop having an inlet 10" and outlet 9" which is essentially the same as that described with reference to Figure 7a.
  • a different configuration of auxiliary separator 16" is employed.
  • the separator 35" and auxiliary separator 16" are reverse lights separators.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Cyclones (AREA)
  • Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
  • Centrifugal Separators (AREA)
  • Paper (AREA)
EP84306608A 1983-10-12 1984-09-28 Traitement des rejets dans les cyclones et autres dispositifs séparateurs Withdrawn EP0138475A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB838327218A GB8327218D0 (en) 1983-10-12 1983-10-12 Reject handling in cyclones &c
GB8327218 1983-10-12

Publications (1)

Publication Number Publication Date
EP0138475A2 true EP0138475A2 (fr) 1985-04-24

Family

ID=10550033

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84306608A Withdrawn EP0138475A2 (fr) 1983-10-12 1984-09-28 Traitement des rejets dans les cyclones et autres dispositifs séparateurs

Country Status (9)

Country Link
EP (1) EP0138475A2 (fr)
JP (1) JPS6099090A (fr)
AU (1) AU3400984A (fr)
ES (1) ES536631A0 (fr)
FI (1) FI843947A7 (fr)
GB (1) GB8327218D0 (fr)
NO (1) NO844049L (fr)
NZ (1) NZ209855A (fr)
ZA (1) ZA847811B (fr)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1986006653A1 (fr) * 1985-05-03 1986-11-20 Larox Oy Procede et appareil de tri hydraulique
WO1989002313A3 (fr) * 1987-09-05 1989-06-15 Serck Baker Ltd Separateur
US4919796A (en) * 1987-09-01 1990-04-24 A. Ahlstrom Corporation Method and apparatus for grading fiber suspension
AU620045B2 (en) * 1987-09-05 1992-02-13 Serck Baker Limited Separator
WO1999024662A1 (fr) * 1997-11-11 1999-05-20 Ahlstrom Machinery Oy Procede et appareil de traitement d'une suspension de fibres
GB2337011A (en) * 1998-05-04 1999-11-10 Hudson Products Corp Monitoring performance of centrifugal gas/oil separation
WO2017016718A1 (fr) * 2015-07-28 2017-02-02 Bta International Gmbh Séparation hydrodynamique des matières lourdes d'une suspension
CN109701759A (zh) * 2019-03-06 2019-05-03 哈尔滨工业大学 背压实时可调型强化旋流分离方法及装置
WO2020057851A1 (fr) * 2018-09-18 2020-03-26 Voith Patent Gmbh Procédé de commande d'un dispositif de nettoyage à séparateur de fraction lourde

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1987005235A1 (fr) * 1986-02-28 1987-09-11 Noel Carroll Separateur a cyclone
JP5803493B2 (ja) * 2011-09-22 2015-11-04 Ｊｆｅスチール株式会社 旋回流式固液分離装置の運転制御装置および運転制御方法
AT512479B1 (de) * 2012-02-10 2013-11-15 Andritz Energy & Environment Gmbh Verfahren zur feinstoffreduktion im rea-gips

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5512831A (en) * 1978-07-06 1980-01-29 Oishi Kikai Seisakusho Kk Debris sorting apparatus from paper making stock

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1986006653A1 (fr) * 1985-05-03 1986-11-20 Larox Oy Procede et appareil de tri hydraulique
US4919796A (en) * 1987-09-01 1990-04-24 A. Ahlstrom Corporation Method and apparatus for grading fiber suspension
WO1989002313A3 (fr) * 1987-09-05 1989-06-15 Serck Baker Ltd Separateur
EP0313197A3 (en) * 1987-09-05 1989-07-26 Serck Baker Limited Separator
GB2231287A (en) * 1987-09-05 1990-11-14 Serck Baker Ltd Separator
US5008014A (en) * 1987-09-05 1991-04-16 Serck Baker Limited Separator
GB2231287B (en) * 1987-09-05 1991-09-04 Serck Baker Ltd Separator
AU620045B2 (en) * 1987-09-05 1992-02-13 Serck Baker Limited Separator
WO1999024662A1 (fr) * 1997-11-11 1999-05-20 Ahlstrom Machinery Oy Procede et appareil de traitement d'une suspension de fibres
GB2337011A (en) * 1998-05-04 1999-11-10 Hudson Products Corp Monitoring performance of centrifugal gas/oil separation
WO2017016718A1 (fr) * 2015-07-28 2017-02-02 Bta International Gmbh Séparation hydrodynamique des matières lourdes d'une suspension
CN107835717A (zh) * 2015-07-28 2018-03-23 Bta国际股份有限公司 从淤浆中水力分离高比重固体
US10173224B2 (en) 2015-07-28 2019-01-08 Bta International Gmbh Hydrodynamic removal of dense materials from a slurry
WO2020057851A1 (fr) * 2018-09-18 2020-03-26 Voith Patent Gmbh Procédé de commande d'un dispositif de nettoyage à séparateur de fraction lourde
CN112714675A (zh) * 2018-09-18 2021-04-27 福伊特专利有限公司 带有重组分分离器的清洁装置的控制方法
CN109701759A (zh) * 2019-03-06 2019-05-03 哈尔滨工业大学 背压实时可调型强化旋流分离方法及装置

Also Published As

Publication number Publication date
FI843947L (fi) 1985-04-13
FI843947A7 (fi) 1985-04-13
AU3400984A (en) 1985-04-18
NO844049L (no) 1985-04-15
ES8602447A1 (es) 1985-12-16
FI843947A0 (fi) 1984-10-09
NZ209855A (en) 1986-03-14
ES536631A0 (es) 1985-12-16
ZA847811B (en) 1985-05-29
GB8327218D0 (en) 1983-11-16
JPS6099090A (ja) 1985-06-01

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Inventor name: CHIVRALL, GRAHAM BLAKELEY