EP0068076B1 - Dispositif de surveillance et de commande pour cellules d'électrolyse chlore-acali à cathode de mercure - Google Patents

Dispositif de surveillance et de commande pour cellules d'électrolyse chlore-acali à cathode de mercure Download PDF

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Publication number
EP0068076B1
EP0068076B1 EP82102107A EP82102107A EP0068076B1 EP 0068076 B1 EP0068076 B1 EP 0068076B1 EP 82102107 A EP82102107 A EP 82102107A EP 82102107 A EP82102107 A EP 82102107A EP 0068076 B1 EP0068076 B1 EP 0068076B1
Authority
EP
European Patent Office
Prior art keywords
current
anodes
cell
signal
adjustable
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.)
Expired
Application number
EP82102107A
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German (de)
English (en)
Other versions
EP0068076A2 (fr
EP0068076A3 (en
Inventor
Peter Fabian
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.)
De Nora Deutschland GmbH
Original Assignee
Heraeus Elektroden GmbH
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
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First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=6134924&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0068076(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Heraeus Elektroden GmbH filed Critical Heraeus Elektroden GmbH
Priority to AT82102107T priority Critical patent/ATE23579T1/de
Publication of EP0068076A2 publication Critical patent/EP0068076A2/fr
Publication of EP0068076A3 publication Critical patent/EP0068076A3/de
Application granted granted Critical
Publication of EP0068076B1 publication Critical patent/EP0068076B1/fr
Expired legal-status Critical Current

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Classifications

    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25BELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B15/00Operating or servicing cells
    • C25B15/04Regulation of the inter-electrode distance

Definitions

  • the invention is based on a method and a device for monitoring and controlling electrolysis cells according to the preamble of claims 1 and 3.
  • Such prior art is known from FR-A-2 236 969.
  • the inventive method is set out in claim 1, the inventive apparatus in claim 3.
  • DSA anodes in conjunction with the monitoring and control device described below can be regarded as an ideal combination.
  • the monitoring and control device consciously dispenses with fully automatic monitoring and control performed by a central computer.
  • the monitoring and control device is housed in an insulating material housing and is used to monitor and control a single electrolysis cell.
  • the electronics are housed in the upper part of the housing.
  • the housing is closed by a transparent cover.
  • the signal and control elements are located in the lower part of the cover.
  • input plug-in cards are accommodated in the plug-in card slots.
  • Each plug-in card has space for two input channels, which are potentially separated from the mains as well as from the outputs.
  • a highly reliable input amplifier with low drift values amplifies the input signal from the supply rails in the order of 5-6 mV to a thousand times the value. This voltage is converted into a proportional frequency via an analog-digital conversion, which is fed to a digital-to-analog converter via an optocoupler.
  • the overall ratio is 1: 1. This measure ensures the necessary electrical isolation between the input circuits and the processing circuit.
  • Each input plug-in card has two power supplies, so that each input channel is supplied independently and electrically separately from the other. This is to be understood as a precautionary measure, because all measuring points within a cell cannot have more than 4-5 V voltage difference.
  • the choice of an optocoupler as the transmission element avoids the magnetic influence that can be influenced by external fields, as occurs in electrolysis systems.
  • the AC voltage coupling has the advantage that the optocoupler can be easily monitored. Even in the event that the optocoupler continuously switches through or interrupts, zero voltage monitoring will immediately show these errors on the stock card.
  • Each input plug-in card has a defect display for each channel.
  • All outputs are added in a further plug-in card and averaged so that the output signal corresponds to the arithmetic mean of the input signals.
  • This mean value amplifier can be set to the number of outputs using a switch on the plug-in card.
  • the corresponding input signals from the supply rails are compared with the mean value according to the number of group adjustment units above the electrolysis cell, and the result is fed to an evaluation circuit.
  • the evaluation circuit compares the individual value with the mean value. If an adjustable percentage tolerance limit above the mean value is exceeded, the device controls the motors of the respective group adjustment unit. The motors raise the anode adjustment device by an adjustable distance. This process is repeated automatically in the event that the overcurrent has not yet been eliminated after an adjustable pause time until the current consumption of the supply rail is within the tolerated size.
  • This process also triggers an optical and acoustic alarm signal.
  • the response of the monitoring circuit is stored until the optical signal is manually deleted.
  • a suitable connection to the cathode of the cell is also routed through an isolation amplifier and displayed on a digital instrument. This means that the operating voltage of the cell can be read from the device at any time.
  • the voltage supply for the contactor control which is secured by special locking circuits with the operating loads even in the event of failure of electronic switching elements such as transistors or the like, is combined with the isolating amplifier of the cell operating voltage on a common plug-in card.
  • the contactors are encapsulated in sheet steel housings.
  • the cell voltage and the average target current consumption of the individual supply rails can be read on the digital displays.
  • the actual current consumption of the individual supply rails can now be queried on the device.
  • the inclination of the frame can now be changed in manual operation by controlling the servomotors on the anode holding frame, so that the current distribution is corrected over the length of the frame. If this measure is not sufficient, the current consumption of the individual power supplies must be checked using a current clamp and adjusted individually.
  • the anode frames can each be lowered in adjustable steps using buttons on the device, bringing the cell to operating voltage.
  • the device automatically blocks during the set pause times and thus prevents the anodes from dropping too quickly.
  • the device monitors the current consumption of the individual supply rails and blocks when the set maximum percentage deviation from the arithmetic mean value of the total current consumption is reached, so that the anodes cannot run the risk of a short circuit.
  • the device controls the actuating motor (s) of the entire anode group and gradually increases them parallel to the cathode by a previously adjustable amount. If the overcurrent is eliminated by this automatically running measure, the device shows until manual acknowledgment which supply rail was in the overcurrent range, so that the operating personnel has an immediate indication of where to correct. After eliminating the interference source causing the overcurrent, the cell can be brought back to the desired voltage by means of a button as described above.
  • the electrolytic cell has a cell trough 6 and a cell cover 9. On the cell cover 9 supports 14 are attached, which carry a frame 11 which serves to adjust the anodes 8.
  • the flowing mercury cathode in the cell trough 6 is designated by 7. Otherwise, the cell structure is known per se.
  • the monitoring and control device 1 is connected to the supply rail 4 by a measuring line 2, via a shunt tap or measuring section 2 '.
  • the supply rail or busbar 4 is electrically conductively connected to the individual anodes 8 by a current supply band 5, but is flexibly connected.
  • the anodes 8 are known per se, e.g. B. arranged in a sleeve power supply bolts, which in turn are provided with adjusting screws 10 for individual adjustment relative to the frame 11.
  • a lifting gear is designated, which is driven by an electric gear motor 13, for. B. on the illustrated horizontal shaft, so that in the manner of a bevel gear drive, the support frame 11 for the anodes 8 is movable up and down on the columns 14, as indicated by arrows.
  • the lines and the fastening elements for the lines to the anodes are advantageously made from the same material as the busbars. Temperature compensation elements are also provided in order to compensate for temperature differences in the individual supply rails.
  • the measuring part can also be designed as a single device, so that a cell that has no motorized adjustment can be readjusted manually.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electrolytic Production Of Metals (AREA)
  • Water Treatment By Electricity Or Magnetism (AREA)
  • Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)

Claims (3)

1. Procédé pour la surveillance et la commande de cellules d'électrolyse, en particulier de cellules d'électrolyse de chlorures alcalins, à anodes métalliques et cathodes en mercure, pour la protection à l'égard d'une surintensité, dans lequel on mesure le courant, amené aux anodes d'une cellule par l'intermédiaire d'une conduite d'amenée, dans un circuit de mesure muni d'une prise shunt, en tant que valeur réelle, sous forme d'un signal de tension et dans lequel, lorsque l'on atteint une surintensité prescrite comme valeur de consigne, on amène ce signal, en tant que signal de commande, à un dispositif de réglage, par pas, de la distance entre l'anode et la cathode, étant précisé que la valeur de consigne est obtenue sous forme d'un signal résultant de la totalisation de toute l'intensité amenée au groupe de cellules, obtenue par mesure par l'intermédiaire de la résistance shunt, puis de la division par le nombre des prises, caractérisé en ce qu'à la mise en service on abaisse les anodes (8) au moyen de palpeurs, par pas réglables, avec temps d'arrêt réglables intermédiaires et que l'on met les cellules sous tension d'exploitation; en ce que pendant l'exploitation, si l'on atteint la surintensité prescrite comme valeur de consigne, toutes les anodes du groupe de cellules sont relevées par pas de valeur réglable, ce processus se répétant, chaque fois après un temps d'arrêt réglable, jusqu'à ce que l'intensité absorbée par la cellule se situe en-dessous de la valuer tolérée; et en ce qu'après avoir atteint cet état, il est signalé quelle conduite amenée était en surintensité.
2. Procédé selon la revendication 1, caractérisé en ce que la signalisation de la valeur de consigne et de la valeur réelle se font numériquement.
3. Dispositif pour la surveillance et la commande de cellules d'électrolyse, en particulier de cellules d'électrolyse de chlorures alcalins, à anodes metalliques et cathodes en mercure, pour la protection à l'égard d'une surintensité, dans lequel on peut mesurer le courant, que l'on peut amener aux anodes (8) d'une cellule par l'intermédiaire d'un conduite d'amenée, dans un circuit de mesure (2) muni d'une prise shunt, en tant que valeur réelle, sous forme d'un signal de tension et dans lequel, lorsque l'on atteint une surintensité prescrite comme valeur de consigne, on amène ce signal, en tant que signal de commande, à un dispositif de réglage, par pas, de la distance entre l'anode (8) et la cathode (7), étant précisé que la valeur de consigne doit être obtenue sous forme d'un signal résultant de la totalisation de toute l'intensité que l'on peut amener au groupe de cellules, obtenue par mesure par l'intermédiaire de la résistance shunt, puis de la division par le nombre des prises, caractérisé en ce qu'à la mise en service on peut abaisser les anodes (8) au moyen de palpeurs, par pas réglables; en ce que, si l'on atteint la surintensité prescrite comme valeur de consigne, on peut relever toutes les anodes (8) du groupe de cellules par pas de valeur réglable; en ce qu'il est prévu une signalisation de la conduite d'amenée (4) concernée par la surintensité; et en ce que l'on peut régler la tension désirée pour la cellule au moyen d'un bouton- poussoir à actionner après avoir supprimé la couse de la surintensité.
EP82102107A 1981-06-19 1982-03-16 Dispositif de surveillance et de commande pour cellules d'électrolyse chlore-acali à cathode de mercure Expired EP0068076B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT82102107T ATE23579T1 (de) 1981-06-19 1982-03-16 Ueberwachungs- und steuerungseinrichtung fuer chloralkalielektrolysezellen mit quecksilberkathode.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3124108A DE3124108C2 (de) 1981-06-19 1981-06-19 Überwachungs- und Steuerungseinrichtung für Elektrolysezellen mit Quecksilberkathoden
DE3124108 1981-06-19

Publications (3)

Publication Number Publication Date
EP0068076A2 EP0068076A2 (fr) 1983-01-05
EP0068076A3 EP0068076A3 (en) 1983-03-23
EP0068076B1 true EP0068076B1 (fr) 1986-11-12

Family

ID=6134924

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82102107A Expired EP0068076B1 (fr) 1981-06-19 1982-03-16 Dispositif de surveillance et de commande pour cellules d'électrolyse chlore-acali à cathode de mercure

Country Status (6)

Country Link
US (1) US4448660A (fr)
EP (1) EP0068076B1 (fr)
AT (1) ATE23579T1 (fr)
CA (1) CA1189825A (fr)
DE (2) DE3124108C2 (fr)
MX (1) MX151556A (fr)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2529913A1 (fr) * 1982-07-07 1984-01-13 Chloe Chemie Dispositif de controle et de visualisation de la repartition du courant dans un electrolyseur
GB8521128D0 (en) * 1985-08-23 1985-10-02 Alcan Int Ltd Controlling anode movement in aluminium cell
DE3908087A1 (de) * 1989-03-13 1990-09-20 Vaw Ver Aluminium Werke Ag Verfahren und vorrichtung zur nachregulierung des polabstandes zum ausgleich des anodenabbrandes bei elektrolysezellen
US5785826A (en) * 1996-12-26 1998-07-28 Digital Matrix Apparatus for electroforming
US5843296A (en) * 1996-12-26 1998-12-01 Digital Matrix Method for electroforming an optical disk stamper
US20040055873A1 (en) * 2002-09-24 2004-03-25 Digital Matrix Corporation Apparatus and method for improved electroforming
KR100865294B1 (ko) 2007-05-16 2008-10-27 삼성전기주식회사 수소 발생 장치 및 연료전지 발전 시스템
ES2764000T3 (es) * 2012-08-17 2020-06-01 Elysis Lp Sistemas y procedimientos para impedir reacciones de termita en celdas electrolíticas

Citations (2)

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Publication number Priority date Publication date Assignee Title
DE2422582A1 (de) * 1973-05-10 1974-11-28 Olin Corp Verfahren und vorrichtung zum einstellen des anoden-kathoden-abstandes in einer elektrolysezelle zur vermeidung von stromueber- oder stromunterbelastungen
DE2432691A1 (de) * 1973-07-10 1975-01-30 Ppg Industries Inc Verfahren zum auffinden von kurzschluessen in quecksilberzellen und zum abgleichen der stromstaerken

Family Cites Families (7)

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Publication number Priority date Publication date Assignee Title
DE1671439A1 (de) * 1965-11-11 1971-09-30 Knapsack Ag Anordnung zur Messung der Stromstaerke an den einzelnen Elektroden von Elektrolysezellen
US3476660A (en) * 1966-03-23 1969-11-04 Ici Ltd Method of sequentially adjusting the anodes in a mercury-cathode cell
US4098666A (en) * 1974-07-18 1978-07-04 Olin Corporation Apparatus for regulating anode-cathode spacing in an electrolytic cell
US4035268A (en) * 1973-09-17 1977-07-12 Produits Chimiques Ugine Kuhlmann Process for the control of mercury cathode electrolysis cells
US4004989A (en) * 1974-04-18 1977-01-25 Olin Corporation Method for automatic adjustment of anodes based upon current density and current
US4098639A (en) * 1975-06-17 1978-07-04 Mo Och Domsjo Aktiebolag Process for reducing the requirement of fresh chemicals without increasing emissions in the pulping of cellulosic material
DE2729732B2 (de) * 1977-07-01 1980-06-26 Hoechst Ag, 6000 Frankfurt Vorrichtung zum Regeln, Überwachen, Optimieren, Bedienen von und zur Informationsdarstellung in Chloralkalielektrolyseanlagen

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2422582A1 (de) * 1973-05-10 1974-11-28 Olin Corp Verfahren und vorrichtung zum einstellen des anoden-kathoden-abstandes in einer elektrolysezelle zur vermeidung von stromueber- oder stromunterbelastungen
DE2432691A1 (de) * 1973-07-10 1975-01-30 Ppg Industries Inc Verfahren zum auffinden von kurzschluessen in quecksilberzellen und zum abgleichen der stromstaerken

Also Published As

Publication number Publication date
CA1189825A (fr) 1985-07-02
EP0068076A2 (fr) 1983-01-05
US4448660A (en) 1984-05-15
DE3274265D1 (en) 1987-01-02
DE3124108A1 (de) 1983-01-13
ATE23579T1 (de) 1986-11-15
EP0068076A3 (en) 1983-03-23
MX151556A (es) 1984-12-13
DE3124108C2 (de) 1986-01-09

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