EP0581196B1 - Controlling a flotation plant having a primary and a secondary stage - Google Patents

Controlling a flotation plant having a primary and a secondary stage Download PDF

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Publication number
EP0581196B1
EP0581196B1 EP93111761A EP93111761A EP0581196B1 EP 0581196 B1 EP0581196 B1 EP 0581196B1 EP 93111761 A EP93111761 A EP 93111761A EP 93111761 A EP93111761 A EP 93111761A EP 0581196 B1 EP0581196 B1 EP 0581196B1
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EP
European Patent Office
Prior art keywords
stage
primary
overflow
primary stage
amount
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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
Application number
EP93111761A
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German (de)
French (fr)
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EP0581196A3 (en
EP0581196A2 (en
Inventor
Peter Schweiss
Hans-Dieter Dörflinger
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JM Voith GmbH
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JM Voith GmbH
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Publication date
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Publication of EP0581196A2 publication Critical patent/EP0581196A2/en
Publication of EP0581196A3 publication Critical patent/EP0581196A3/xx
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Publication of EP0581196B1 publication Critical patent/EP0581196B1/en
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    • 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
    • B03D1/028—Control and monitoring of flotation processes; computer models therefor
    • 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
    • B03D1/1406—Flotation machines with special arrangement of a plurality of flotation cells, e.g. positioning a flotation cell inside another
    • 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
    • B03D1/1443—Feed or discharge mechanisms for flotation tanks
    • B03D1/1462—Discharge mechanisms for the froth

Definitions

  • the invention relates to the control of a flotation plant according to the preamble of the claim.
  • a flotation plant in which the amount of foam of the primary flotation is regulated by returning cleaned suspension from the secondary to the primary flotation.
  • the amount of foam in the secondary flotation is not adjusted by regulating the suspension introduced into the secondary stage, but by foam discharge via a valve attached directly to the cell. With this control procedure, it was necessary to continuously check the overflow quantities on site at the secondary stage and to correct the level setpoints.
  • the constant accumulation height also means a constant overflow amount due to the measuring weir in or at the end of the foam channel.
  • the measurement of the primary cell level only serves as an additional control display.
  • the foam channel level (small volume) is sensitive to changes in the primary overflow volume, which is why the primary overflow volume can be set very precisely and reproducibly using the bypass valve.
  • the secondary stage is always fed with a constant amount due to the constant level of the foam channel, which means that the secondary overflow and the amount of return material are largely constant.
  • the inflow amount to the secondary stage is constant, but the air content in the secondary stage can change, whereby the overflow amount can vary despite the unchanged level transmitter display.
  • the secondary cell overflow quantity is controlled by measuring the secondary foam channel level in front of an outlet weir (vertical slot approx. 15 mm wide) and an indirect level control of the secondary foam channel by changing the amount of return material.
  • the foam channel level (small volume) reacts so sensitively to changes in the overflow quantity that the influence of different air contents in the overflow material is negligibly small and is reproducible Relationship between foam channel level and overflow quantity results.
  • primary stage 1 essentially consists of the individual flotation cells 20, 20 ', etc., which are connected in series and each of which is assigned an injector 22, 22' or another supply apparatus for the suspension to be flotated.
  • the supply lines to the injectors are labeled 21, 21 'etc.
  • a foam channel 12 is common to all flotation cells, and the cleaned suspension flows to the flotation cell via a weir.
  • the primary flotation stage has a measuring weir 28 in the foam channel or at the end of the foam channel.
  • the secondary stage 2 is constructed similarly with individual cells 61, 61 ', injectors 62 and 62', the conduction between the two cells being carried out by line 63.
  • a foam channel 72 is also provided here, of which a weir 78 is also connected upstream.
  • a measuring weir 29 at the end or inside the foam channel.
  • the levels are preferably measured by pressure transmitters 51 and 53, respectively.
  • controllers 52 and 54 control the quantity of accepted material in the primary stage via valve 47 and the return flow to the primary stage from the secondary stage of flotation via valve 49.
  • the amount of foam or overflow of the primary stage is fed via line 36 to a hydrocyclone 10, with the aid of which the foam-containing suspension is vented, as is known from EP 0447887. With its conical end, it dips into a container 38 located deep, for example in the basement, from which a pump 44 conveys the suspension to line 46.
  • a pressure sensor 45 is used to keep the level in the container 38 constant as well as regulator 56 and valve 45 in line 42, via which a circulation quantity (in the bypass) is led to the secondary flotation stage 2.

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  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Biotechnology (AREA)
  • General Engineering & Computer Science (AREA)
  • Paper (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Physical Water Treatments (AREA)
  • Analysing Materials By The Use Of Radiation (AREA)

Abstract

The invention relates to controlling a flotation plant comprising primary cells, of a primary stage, each equipped with a froth overflow, and secondary cells downstream of these for the overflow amounts. The invention is characterised by the features: a) setting the overflow height, which is then left unchanged, to the froth channel in the flotation cell of the primary stage; b) damming the froth and measuring the damming height in the froth channel of the primary stage; c) controlling, dependent on this measurement signal, the amount of material of the primary stage to as constant as possible or approximately constant damming height of the flow channel of the primary stage; d) separating out air from the overflow amount of the primary stage, passing the same to a collection vessel low down; e) returning the amount of material of the secondary stage in part to the primary stage and in part as a by-pass amount to the secondary stage upstream of the pump conveying material from the collection vessel for the primary stage to the secondary stage and downstream of this collection vessel; f) controlling the level in the collection vessel for the overflow amount of the primary stage via the by-pass amount to the secondary stage; g) measuring the level in the froth channel of the secondary stage upstream of an outlet weir of the same and controlling the ratio of the amount returned to the primary stage and the by-pass amount going to the secondary stage, in dependence on this measurement signal. <IMAGE>

Description

Die Erfindung betrifft die Regelung einer Flotationsanlage entsprechend dem Oberbegriff des Anspruchs. Bei solchen Anlagen besteht eine Schwierigkeit in der Regelung der beiden Flotationsstufen wegen der erzeugten Schaummenge und der zu flotierenden lufthaltigen Suspension. Aus der EP 0391042 ist eine Regelung einer Flotationsanlage bekannt, bei der zwar durch Rückführen gereinigter Suspension von der Sekundär- zur Primärflotation die Schaummenge der Primärflotation geregelt wird. Die Einstellung der Schaummenge in der Sekundärflotation erfolgt jedoch nicht durch eine Regelung der in die Sekundärstufe eingebrachten Suspension, sondern durch Schaumaustrag über ein direkt an der Zelle angebrachtes Ventil. Bei diesem Regelungsverfahren war es nötig, laufend eine Überprüfung der Überlaufmengen an der Sekundärstufe vor Ort und eine Korrektur der Niveau-Sollwerte vorzunehmen.The invention relates to the control of a flotation plant according to the preamble of the claim. In such systems, there is a difficulty in controlling the two flotation stages because of the amount of foam generated and the air-containing suspension to be floated. From EP 0391042 a regulation of a flotation plant is known, in which the amount of foam of the primary flotation is regulated by returning cleaned suspension from the secondary to the primary flotation. However, the amount of foam in the secondary flotation is not adjusted by regulating the suspension introduced into the secondary stage, but by foam discharge via a valve attached directly to the cell. With this control procedure, it was necessary to continuously check the overflow quantities on site at the secondary stage and to correct the level setpoints.

Eine weitgehend automatische Regelung wird erfindungsgemäß durch die Merkmale des kennzeichnenden Teils des Anspruchs erzielt.A largely automatic regulation is achieved according to the invention by the features of the characterizing part of the claim.

Es ergibt sich folgendes Regelungsprinzip:
Regelung der Primärzellenüberlaufmenge durch Messung des Primärschaumrinnenniveaus und einer indirekten Niveauregelung der Primärschaumrinne durch Veränderung der Gutstoffmenge (Primärzellenniveau) bei festgehaltener Zulaufmenge zur Flotation (Flow-Regelung).The following principle of regulation results:
Regulation of the primary cell overflow quantity by measuring the primary foam channel level and an indirect level control of the primary foam channel by changing the amount of accepted material (primary cell level) with a fixed supply quantity for flotation (flow control).

Die konstante Stauhöhe bedeutet auch eine konstante Überlaufmenge wegen des Meßwehrs in oder am Ende der Schaumrinne.The constant accumulation height also means a constant overflow amount due to the measuring weir in or at the end of the foam channel.

Die Messung des Primärzellenniveaus dient nur als zusätzliche Kontrollanzeige.The measurement of the primary cell level only serves as an additional control display.

Die Vorteile sind:The advantages are:

Das Schaumrinnenniveau (kleines Volumen) reagiert empfindlich auf Änderungen der Primärüberlaufmenge, weshalb sich sehr genau und reproduzierbar die Primärüberlaufmenge über das Bypaßventll einstellen läßt.The foam channel level (small volume) is sensitive to changes in the primary overflow volume, which is why the primary overflow volume can be set very precisely and reproducibly using the bypass valve.

Die Sekundärstufe wird wegen des gleichbleibenden Schaumrinnenniveaus immer mit einer konstanten Menge beschickt, wodurch die Sekundär-Überlaufmenge und die Rückstoffmenge weitgehend konstant sind.The secondary stage is always fed with a constant amount due to the constant level of the foam channel, which means that the secondary overflow and the amount of return material are largely constant.

Durch die "Schaumrinnenregelung" der Primärstufe ist zwar die Zulaufmenge zur Sekundärstufe konstant, aber der Luftgehalt in der Sekundärstufe kann sich verändern, wodurch die Überlaufmenge trotz unveränderter Niveautransmitteranzeige variieren kann.Due to the "foam channel control" of the primary stage, the inflow amount to the secondary stage is constant, but the air content in the secondary stage can change, whereby the overflow amount can vary despite the unchanged level transmitter display.

Durch die "Schaumrinnenregelung" an der Sekundärstufe kann dieser Effekt weitgehend eliminiert werden.This effect can be largely eliminated by the "foam channel control" on the secondary stage.

Es erfolgt die Regelung der Sekundärzellen-Überlaufmenge durch Messung des Sekundär-Schaumrinnenniveaus vor einem Auslaufwehr (vertikaler Schlitz ca. 15 mm breit) und eine indirekte Niveauregelung der Sekundär-Schaumrinne durch Veränderungen der Rückstoffmenge.The secondary cell overflow quantity is controlled by measuring the secondary foam channel level in front of an outlet weir (vertical slot approx. 15 mm wide) and an indirect level control of the secondary foam channel by changing the amount of return material.

Zwischen der Stauhöhe (Schaumrinnenniveau) vor einem Wehr und der Durchlaufmenge am Wehr besteht ein direkter und reproduzierbarer Zusammenhang (freier Abfluß nach dem Wehr), weshalb durch die Einstellung des Schaumrinnenniveaus die Sekundär-Überlaufmenge festgelegt werden kann.There is a direct and reproducible correlation (free discharge after the weir) between the height of the dam (foam channel level) in front of a weir and the flow rate at the weir, which is why the secondary overflow quantity can be determined by setting the foam channel level.

Das Schaumrinnenniveau (kleines Volumen) reagiert so empfindlich auf Veränderungen der Überlaufmenge, daß der Einfluß unterschiedlicher Luftgehalte im Überlaufstoff vernachlässigbar klein ist und sich ein reproduzierbarer Zusammenhang zwischen Schaumrinnenniveau und Überlaufmenge ergibt.The foam channel level (small volume) reacts so sensitively to changes in the overflow quantity that the influence of different air contents in the overflow material is negligibly small and is reproducible Relationship between foam channel level and overflow quantity results.

Nachfolgend wird die Erfindung anhand der Figur der Zeichnung erläutert, die ein Prinzipschema darstellt.The invention is explained below with reference to the figure of the drawing, which represents a schematic diagram.

Die Primärstufe 1 besteht im wesentlichen nach der Mischkammer aus den einzelnen in Reihe geschalteten Flotationszellen 20, 20' usw., denen jeweils ein Injektor 22, 22' oder ein sonstiger Zufuhrapparat für die zu flotierende Suspension zugeordnet ist. Die Zufuhrleitungen zu den Injektoren sind mit 21, 21' usw. bezeichnet. Allen Flotationszellen ist hier eine Schaumrinne 12 gemeinsam, der die gereinigte Suspension jeweils über ein Wehr der Flotationszelle zufließt. Ferner weist die Flotations-Primärstufe in der Schaumrinne oder am Ende der Schaumrinne ein Meßwehr 28 auf. Ähnlich ist die Sekundärstufe 2 aufgebaut mit einzelnen Zellen 61, 61', Injektoren 62 und 62', wobei die Überleitung zwischen den beiden Zellen durch Leitung 63 erfolgt. Es ist auch hier eine Schaumrinne 72 vorgesehen, deren auch jeweils ein Wehr 78 vorgeschaltet ist. Auch hier befindet sich am Ende bzw. innerhalb der Schaumrinne ein Meßwehr 29. Vor den Meßwehren werden jeweils die Niveaus vorzugsweise durch Drucktransmitter 51 bzw. 53 gemessen. Regler 52 bzw. 54 steuern einerseits die Gutstoffmenge der Primärstufe über Ventil 47 und die Rücklaufmenge zur Primärstufe von der Sekundärstufe der Flotation über Ventil 49.After the mixing chamber, primary stage 1 essentially consists of the individual flotation cells 20, 20 ', etc., which are connected in series and each of which is assigned an injector 22, 22' or another supply apparatus for the suspension to be flotated. The supply lines to the injectors are labeled 21, 21 'etc. A foam channel 12 is common to all flotation cells, and the cleaned suspension flows to the flotation cell via a weir. Furthermore, the primary flotation stage has a measuring weir 28 in the foam channel or at the end of the foam channel. The secondary stage 2 is constructed similarly with individual cells 61, 61 ', injectors 62 and 62', the conduction between the two cells being carried out by line 63. A foam channel 72 is also provided here, of which a weir 78 is also connected upstream. Here, too, there is a measuring weir 29 at the end or inside the foam channel. In front of the measuring weirs, the levels are preferably measured by pressure transmitters 51 and 53, respectively. On the one hand, controllers 52 and 54 control the quantity of accepted material in the primary stage via valve 47 and the return flow to the primary stage from the secondary stage of flotation via valve 49.

Die Schaummenge bzw. Überlaufmenge der Primärstufe wird über Leitung 36 zu einem Hydrozyklon 10 geführt, mit dessen Hilfe die Entlüftung der schaumhaltigen Suspension vorgenommen wird, wie aus der EP 0447887 bekannt. Mit seinem konischen Ende taucht er in einen tief - z.B. im Keller - gelegenen Behälter 38 ein, aus dem eine Pumpe 44 die Suspension zur Leitung 46 fördert. Zur Konstanthaltung des Niveaus in dem Behälter 38 dient ein Druckaufnehmer 45 sowie Regler 56 und Ventil 45 in Leitung 42, über welche eine Kreislaufmenge (im Bypaß) zur Sekundär-Flotationsstufe 2 geführt wird.The amount of foam or overflow of the primary stage is fed via line 36 to a hydrocyclone 10, with the aid of which the foam-containing suspension is vented, as is known from EP 0447887. With its conical end, it dips into a container 38 located deep, for example in the basement, from which a pump 44 conveys the suspension to line 46. A pressure sensor 45 is used to keep the level in the container 38 constant as well as regulator 56 and valve 45 in line 42, via which a circulation quantity (in the bypass) is led to the secondary flotation stage 2.

Im wesentlichen bleibt die Einstellung der Wehre in den bzw. an den einzelnen Flotationszellen konstant, und entsprechend der verlangten Produktionsmenge werden die von den Reglern gesteuerten Mengen allein geändert. Dies ergibt einfache und klare Regelungsverhältnisse.Essentially, the weirs' setting in or on the individual flotation cells remains constant, and the quantities controlled by the controllers alone are changed in accordance with the required production quantity. This results in simple and clear regulatory relationships.

Claims (1)

  1. Control for a primary stage (1) comprising primary cells fitted with a respective foam overflow as well as a respective communal overflow channel for all cells, and downstream of the latter for a flotation plant comprising secondary cells for the overflow volumes with overflow channel of a secondary stage (2), with the feed volume being set according to the production input, and the control includes:
    a) setting a then unchanged overflow height to the foam channel (12) in the primary stage (1);
    b) stowing the foam and measuring the stowing height in the foam channel (12) of the primary stage (1), offering a first measuring signal;
    c) control in dependence of the first measuring signal of the substance volume of the primary stage (1) to an as near as possible or virtually constant stowing height of the foam channel (12) in the primary stage;
    and characterised by the following additional features:
    d) discharge of air from the overflow volume of the primary stage (1) whilst ducting it to a container (38) in a lower position;
    e) feedback of the substance of the secondary stage (2), partially to the primary stage (1) and partially as a bypass volume to the secondary stage (2) to in front of the pump (44) which conveys from the collecting container (38) for the primary stage (1) to the secondary stage (2) and to this collecting container (38);
    f) level control in the container (38) for the overflow volume of the primary stage (1) via the bypass volume to the secondary stage (2);
    g) measuring the level height in the foam channel (72) of the secondary stage (2) in front of a drainage weir (78) of the latter, offering a second measuring signal and control of the ratio of feedback volume ducted from the primary stage (1) and of the bypass volume going to the secondary stage (2) in dependence of said second measuring signal.
EP93111761A 1992-07-30 1993-07-22 Controlling a flotation plant having a primary and a secondary stage Expired - Lifetime EP0581196B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4225117 1992-07-30
DE4225117A DE4225117C1 (en) 1992-07-30 1992-07-30 Flotation plant with primary and secondary stage

Publications (3)

Publication Number Publication Date
EP0581196A2 EP0581196A2 (en) 1994-02-02
EP0581196A3 EP0581196A3 (en) 1994-04-13
EP0581196B1 true EP0581196B1 (en) 1996-12-04

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EP93111761A Expired - Lifetime EP0581196B1 (en) 1992-07-30 1993-07-22 Controlling a flotation plant having a primary and a secondary stage

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US (1) US5330655A (en)
EP (1) EP0581196B1 (en)
JP (1) JPH06154655A (en)
AT (1) ATE145840T1 (en)
BR (1) BR9302561A (en)
CA (1) CA2101710A1 (en)
DE (1) DE4225117C1 (en)
FI (1) FI933396A (en)
NO (1) NO300005B1 (en)

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CN102225370B (en) * 2011-05-24 2013-01-23 东北大学 Flotation impurity-removing method for asbestos-containing talcose ore
CN102744159B (en) * 2012-06-14 2016-01-20 甘肃酒钢集团宏兴钢铁股份有限公司 A kind of method for floating improving copper sulfide ore mineral processing index
CN104668108A (en) * 2014-12-29 2015-06-03 山东东山王楼煤矿有限公司 Flotation device and method for coal slime
CN105583069B (en) * 2015-12-21 2018-02-23 中南大学 A kind of dressing method of high-phosphor oolitic hematite
CN105903574A (en) * 2016-04-13 2016-08-31 中国矿业大学 Emulsification control adding equipment for flotation reagents
CN105689156A (en) * 2016-04-20 2016-06-22 江西铜业股份有限公司 Method for controlling and adjusting flotation cell surfaces
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Publication number Publication date
CA2101710A1 (en) 1994-01-31
NO932733D0 (en) 1993-07-29
EP0581196A3 (en) 1994-04-13
NO932733L (en) 1994-01-31
BR9302561A (en) 1994-03-22
US5330655A (en) 1994-07-19
FI933396A (en) 1994-01-31
NO300005B1 (en) 1997-03-17
DE4225117C1 (en) 1994-03-31
FI933396A0 (en) 1993-07-29
ATE145840T1 (en) 1996-12-15
EP0581196A2 (en) 1994-02-02
JPH06154655A (en) 1994-06-03

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