[go: up one dir, main page]

WO1993000573A1 - Detecteur de niveau d'interface - Google Patents

Detecteur de niveau d'interface Download PDF

Info

Publication number
WO1993000573A1
WO1993000573A1 PCT/EP1991/001185 EP9101185W WO9300573A1 WO 1993000573 A1 WO1993000573 A1 WO 1993000573A1 EP 9101185 W EP9101185 W EP 9101185W WO 9300573 A1 WO9300573 A1 WO 9300573A1
Authority
WO
WIPO (PCT)
Prior art keywords
detectors
probe
conductivity
interface level
interface
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/EP1991/001185
Other languages
English (en)
Inventor
Falk Alexander Schakowski
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.)
Endress and Hauser SE and Co KG
Original Assignee
Endress and Hauser SE and Co KG
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 Endress and Hauser SE and Co KG filed Critical Endress and Hauser SE and Co KG
Priority to PCT/EP1991/001185 priority Critical patent/WO1993000573A1/fr
Publication of WO1993000573A1 publication Critical patent/WO1993000573A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
    • G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
    • G01F23/24—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of resistance of resistors due to contact with conductor fluid
    • G01F23/241—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of resistance of resistors due to contact with conductor fluid for discrete levels
    • G01F23/243—Schematic arrangements of probes combined with measuring circuits
    • 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
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
    • G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
    • G01F23/24—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of resistance of resistors due to contact with conductor fluid
    • G01F23/241—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of resistance of resistors due to contact with conductor fluid for discrete levels
    • G01F23/242—Mounting arrangements for electrodes

Definitions

  • This invention relates to an interface level detector by which term is meant a detector for detecting the position of a fluctuating interface level between two media which may be immiscible liquids, a liquid and a froth, and either a liquid or froth and a gas thereabove, such as air.
  • detectors for automatically detecting an interface level have, in general terms, not been adequately reliable for employment as part of an automatic process control arrangement, particularly in instances where a froth and pulp interface is to be controlled, and most particularly where such froth is deep and of high density.
  • Prior art interface level detectors have, as far as applicant is aware, operated on the basis of detecting changes in density, electrical capacitance, electrical conductivity, and also electrical resistance.
  • one arrangement which has been employed with reasonable, but inadequately reliable results is one in which the different resistivity of two media on each side of an interface has been employed, in combination with potentiometric resistance measurements to give an analogue output which is proportional to the interface level.
  • Such an arrangement has, in particular in the case where the conductivity of the froth is almost equal to, or greater than, about half the conductivity of the liquid, been inadequately accurate as a measurement technique.
  • each electrode has been sequentially paired with a single, fixed, reference electrode which is usually located either at the top or the bottom of the probe.
  • a single, fixed, reference electrode which is usually located either at the top or the bottom of the probe.
  • a method of detecting an interface level between two media including the detection of the conductivity at a series of different levels relevant to the interface to be detected and determining between which two of the series a change in conductivity takes place.
  • an interface level detector comprising a probe adapted for upstanding location in a container in which an interface level is to be detected, said probe being provided with a series of detectors spaced apart along at least a portion of the length of the probe and adapted for detecting the conductivity of a surrounding medium between two operatively, and either temporarily or permanently paired detectors, at a series of positions along said portion of the length of the probe; and control circuitry for applying a voltage between the paired detectors to determine the conductivity of the surrounding medium at said series of positions, said control circuitry also having means for identifying the two adjacent paired detectors between which the conductivity changes.
  • the probe to have a reference detector pair at an operatively lower region thereof; for the detectors to be either arranged in pairs thereof at selected positions along said portion of the length of the probe, or for the detectors to be arranged to be intermittently paired with an axially adjacent detector and, in particular, for the detectors of each temporary or permanent pair thereof to be located at opposite sides of the probe; for the means for applying the voltage across the members of a detector pair to provide an alternating current output, for such output to be applied sequentially to the detector pairs of the series thereof; and for a comparator to compare each conductivity measurement of any detector pair with that of the reference detector pair.
  • FIG. 1 is a schematic illustration of a probe and associated circuitry according to this invention
  • FIG. 2 illustrates a section of the length of a probe having one detector pair associated therewith
  • FIG. 3 illustrates a section of the length of an alternative probe.
  • an interface level detector probe generally indicated by numeral 1
  • a series of temporarily paired detectors the pairs being indicated in Fig. 1, for illustrative purposes, by numeral 2.
  • the series extends along the length of the probe and 5 the pairs are effectively located at a series of equally spaced positions.
  • the individual detectors or electrodes 3 are arranged in two rows extending along the length of ⁇ jO the probe, with one row being located on each diammetrically opposite side of the probe.
  • the detectors of each row thereof are equally spaced but are located centrally between two detectors of the other row thereof.
  • These detectors are 5 arranged to be intermittently paired with a detector of one row being temporarily paired with the next lower electrode of the other row thereof, followed by the pairing of the latter with the next lower of the first row.
  • the individual detectors are carried on a tubular support 5 and the electrical leads 6 to the detector members are passed centrally through the tube and are encased in insulating resinous material 7.
  • Spacing between the positions of location of the detectors is* chosen such that proper control can be exercised on a process or the like once it is known that the interface level is located between any particular two adjacent, temporarily paired, electrodes.
  • the lowermost detector pair 2a (see Fig. 1) serves as a reference detector pair and is arranged such that it will always be immersed in the lower of the two media, the interface between which is to be detected.
  • the interface level detector is particularly adapted for use in detecting the interface level between a liquid 8, and a froth 9, in a froth flotation process.
  • the control circuitry for use in conjunction with the detector probe described above includes a sinewave generator 10 for generating an alternating current voltage and a multiplexing circuit 11 adapted to intermittently pair the detectors and connect each of such detector pairs (other than the lowermost reference electrode pair) sequentially to the sinewave generator so that the conductivity of the medium present between the members of each intermittently formed detector pair can be measured sequentially.
  • thirty electrode pairs were employed.
  • a sample and hold and multiplexing circuits were adapted to scan the 0 electrode pairs fourteen or fifteen times and then average the reading to provide an output reading related to conductivity at each electrode pair position which could then be recorded permanently for subsequent analysis, if required.
  • Such a set of conductivity readings can be employed, where required, to construct a conductivity profile through either or both media.
  • the detectors could be permanently paired.
  • the individual detectors 15 of a permanent pair could be located at the same axial position and each pair would then acquire two conductors to service it.

Landscapes

  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
  • Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)

Abstract

Détecteur de niveau d'interface servant à détecter la position verticale de l'interface entre deux milieux différents pouvant être des liquides immiscibles, un liquide (8) et une écume (9), ou un liquide, ou une écume et un gaz. Le détecteur comporte une sonde (1) dotée d'une série de détecteurs (2), généralement sous forme d'électrodes (3) espacées sur sa longueur et disposées pour pouvoir s'apparier de manière provisoire ou permanente avec une électrode voisine de manière à déterminer entre elles la conductivité d'un milieu environnant par rapport à un détecteur de référence (2a). Des circuits de commande (10, 11, 12, 13) déterminent de manière séquentielle cette conductivité entre des paires d'électrodes au niveau d'une série d'emplacements répartis le long de la sonde, et indiquent la position dans laquelle la conductivité se modifie, ce qui correspond à l'emplacement de l'interface.
PCT/EP1991/001185 1991-06-25 1991-06-25 Detecteur de niveau d'interface Ceased WO1993000573A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/EP1991/001185 WO1993000573A1 (fr) 1991-06-25 1991-06-25 Detecteur de niveau d'interface

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/EP1991/001185 WO1993000573A1 (fr) 1991-06-25 1991-06-25 Detecteur de niveau d'interface

Publications (1)

Publication Number Publication Date
WO1993000573A1 true WO1993000573A1 (fr) 1993-01-07

Family

ID=8165597

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1991/001185 Ceased WO1993000573A1 (fr) 1991-06-25 1991-06-25 Detecteur de niveau d'interface

Country Status (1)

Country Link
WO (1) WO1993000573A1 (fr)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1994018528A1 (fr) * 1993-02-15 1994-08-18 Jean Claude Diverrez Procede de mesure d'au moins une caracteristique d'une solution liquide et moyens pour la mise en ×uvre de ladite solution
EP0627615A1 (fr) * 1993-05-29 1994-12-07 Solartron Group Limited Système à mesure de niveau de liquide
EP0618428A3 (fr) * 1993-03-27 1995-11-22 Solartron Transducers Ltd Systèmes de détection du niveau de fluide.
US5701595A (en) * 1995-05-04 1997-12-23 Nippondenso Co., Ltd. Half duplex RF transceiver having low transmit path signal loss
GR1002979B (el) * 1997-10-15 1998-09-23 Συσκευη ενδειξεων σταθμης του περιεχομενου αγωγιμου υγρου δεξαμενης
EP0907070A1 (fr) * 1997-10-01 1999-04-07 G. Cartier Electronique Capteur de niveau de liquide, notamment pour une installation de refroidissement du moteur thermique d'un véhicule automobile
EP1067368A1 (fr) * 1999-07-08 2001-01-10 HELIOS AG Niveaumessung und Wägetechnik Dispositif de mesure du niveau
GB2354585A (en) * 1999-09-27 2001-03-28 Charis Technology Ltd Apparatus for sensing the level of a fluid in a container
CN103115948A (zh) * 2012-12-18 2013-05-22 华东师范大学 一种不均匀溶液的多段液面电导率测量装置
CN103842780A (zh) * 2011-08-18 2014-06-04 奥图泰有限公司 用于浮选室的探针布置
WO2018067169A1 (fr) * 2016-10-07 2018-04-12 Hewlett-Packard Development Company, L.P. Réservoir de fluide ayant une propriété de fluide et une fonction de détection de niveau

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
LU41530A1 (fr) * 1961-04-28 1962-06-12
US3370466A (en) * 1965-09-24 1968-02-27 United States Steel Corp Method and apparatus for locating interfaces between fluids
US4169377A (en) * 1978-04-17 1979-10-02 Nalco Chemical Company Quantity sensing system for a container
US4382382A (en) * 1979-11-01 1983-05-10 General Electric Company Multilevel liquid sensing system
US4739658A (en) * 1986-04-02 1988-04-26 Nuvatec, Inc. Level sensing system
FR2638521A1 (fr) * 1988-10-28 1990-05-04 Centre Nat Rech Scient Limnigraphe electronique
FR2657691A1 (fr) * 1990-01-31 1991-08-02 Centre Nat Rech Scient Limnigraphe electronique et procede de fabrication.

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
LU41530A1 (fr) * 1961-04-28 1962-06-12
US3370466A (en) * 1965-09-24 1968-02-27 United States Steel Corp Method and apparatus for locating interfaces between fluids
US4169377A (en) * 1978-04-17 1979-10-02 Nalco Chemical Company Quantity sensing system for a container
US4382382A (en) * 1979-11-01 1983-05-10 General Electric Company Multilevel liquid sensing system
US4739658A (en) * 1986-04-02 1988-04-26 Nuvatec, Inc. Level sensing system
FR2638521A1 (fr) * 1988-10-28 1990-05-04 Centre Nat Rech Scient Limnigraphe electronique
FR2657691A1 (fr) * 1990-01-31 1991-08-02 Centre Nat Rech Scient Limnigraphe electronique et procede de fabrication.

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1994018528A1 (fr) * 1993-02-15 1994-08-18 Jean Claude Diverrez Procede de mesure d'au moins une caracteristique d'une solution liquide et moyens pour la mise en ×uvre de ladite solution
FR2701566A1 (fr) * 1993-02-15 1994-08-19 Diverrez Jean Claude Procédé de mesure d'au moins une caractéristique d'une solution liquide et moyens pour la mise en Óoeuvre de la dite solution.
EP0618428A3 (fr) * 1993-03-27 1995-11-22 Solartron Transducers Ltd Systèmes de détection du niveau de fluide.
EP0627615A1 (fr) * 1993-05-29 1994-12-07 Solartron Group Limited Système à mesure de niveau de liquide
US5553494A (en) * 1993-05-29 1996-09-10 Solartron Group Limited Fluid level sensing systems
US5701595A (en) * 1995-05-04 1997-12-23 Nippondenso Co., Ltd. Half duplex RF transceiver having low transmit path signal loss
EP0907070A1 (fr) * 1997-10-01 1999-04-07 G. Cartier Electronique Capteur de niveau de liquide, notamment pour une installation de refroidissement du moteur thermique d'un véhicule automobile
GR1002979B (el) * 1997-10-15 1998-09-23 Συσκευη ενδειξεων σταθμης του περιεχομενου αγωγιμου υγρου δεξαμενης
EP1067368A1 (fr) * 1999-07-08 2001-01-10 HELIOS AG Niveaumessung und Wägetechnik Dispositif de mesure du niveau
GB2354585A (en) * 1999-09-27 2001-03-28 Charis Technology Ltd Apparatus for sensing the level of a fluid in a container
GB2354585B (en) * 1999-09-27 2004-06-23 Charis Technology Ltd Apparatus for sensing the level of a conductive fluid
CN103842780A (zh) * 2011-08-18 2014-06-04 奥图泰有限公司 用于浮选室的探针布置
EP2745084A4 (fr) * 2011-08-18 2015-03-18 Outotec Oyj Agencement de sonde pour une cellule de flottation
AU2011375142B2 (en) * 2011-08-18 2015-07-02 Outotec Oyj Probe arrangement for a flotation cell
CN103115948A (zh) * 2012-12-18 2013-05-22 华东师范大学 一种不均匀溶液的多段液面电导率测量装置
CN103115948B (zh) * 2012-12-18 2015-04-08 华东师范大学 一种不均匀溶液的多段液面电导率测量装置
WO2018067169A1 (fr) * 2016-10-07 2018-04-12 Hewlett-Packard Development Company, L.P. Réservoir de fluide ayant une propriété de fluide et une fonction de détection de niveau
US10576748B2 (en) 2016-10-07 2020-03-03 Hewlett-Packard Development Company, L.P. Fluid reservoir with fluid property and level detection

Similar Documents

Publication Publication Date Title
US6255954B1 (en) Detection of wear-particles and other impurities in industrial or other fluids
WO1993000573A1 (fr) Detecteur de niveau d'interface
EP0244033A2 (fr) Procédés et dispositif pour la détermination par réflectométrie en domaine temporel de la proportion relative, de la quantité de fluide et de la turbulence
US4652811A (en) Method for measuring liquid content in a porous medium such as soil
US20100295565A1 (en) Automated phase separation and fuel quality sensor
EP0104379A1 (fr) Appareil pour indiquer à distance la position angulaire
DK163380B (da) Apparat til maaling af vaeskeniveau og vaeskemaengde
US9383330B2 (en) Arrangement for determining the phase distribution in multiphase media having at least one highly conductive phase
ATE434752T1 (de) Mikrosensor zur positionsmessung von fluessigkeiten in kapillaren
US4181882A (en) Corrosion monitoring apparatus
EP0112002A2 (fr) Sonde pour détecter le niveau de liquide
WO1996010743A1 (fr) Cassette a gel et dispositif d'electrophorese
RU2366905C1 (ru) Устройство для емкостного определения и/или контроля уровня заполнения
JP2022529498A (ja) 二重極性相互容量式液体検知
US4736623A (en) Leak detector
JP4418887B2 (ja) 被乾燥物含水率の非破壊計測方法
CN109540971A (zh) 导电膜均匀性检测装置、系统以及方法
Dai et al. Long-term monitoring of timber moisture content below the fiber saturation point using wood resistance sensors
SE465140B (sv) Foerfarande och anordning foer att bestaemma blods saenkningsreaktion
US8513958B2 (en) Stacked sensor for testing a porous medium
US4736622A (en) Method for detecting leaks in an above ground petroleum storage tank
US4885529A (en) Identification of fluids and an interface between fluids by measuring complex impedance
US7021137B1 (en) Apparatus for rapidly measuring liquid levels and volume of groundwater within wells that eliminates cross contamination between wells
CA2054490C (fr) Capteur de niveau de particules
EP0091270A2 (fr) Arrangement pour mesurer la résistivité dans un puits

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AU CA JP SU US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IT LU NL SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
NENP Non-entry into the national phase

Ref country code: CA

122 Ep: pct application non-entry in european phase