JPS6213589A - Method and apparatus for preventing inverse current in electrolytic cell - Google Patents

Abstract

PURPOSE:To prevent the consumption of an anode due to the reduction of a noble metal oxide on the anode surface by passing a minute current from the anode to a cathode to block the inverse current from the cathode to the anode when a main electric power source for an electrolytic cell contg. various kinds of solns. is cut off. CONSTITUTION:An oxide-coated anode 3 having excellent electric characteristics is used in the electrolysis of an aq. NaCl soln., etc. Namely, a noble metal such as Pt, Ir, Ru, Pd, etc., mixed with a small amt. of a base metal is coated on the surface of a substrate of Ti, etc., and baked to obtain the oxide-coated electrode which is used. A relay circuit 23 is arranged between a power rectifier 6 for an electrolytic cell and an AC electric power source 20. An electrolyte is supplied from a feed pipe 1, electrolysis is carried out between the anode 3 and a cathode 4 and the waste liq. is discharged from a discharge pipe 5. When a switch 26 for electrolysis of the rectifier 6 is cut off, the second relay circuit 28 is operated, a minute DC voltage is impressed between the anode 3 and the cathode 4, hence the inverse current from the cathode 4 to the anode 3 is blocked and the consumption of the noble metal due to the reduction of the oxide on the anode surface by the inverse current is prevented. Furthermore, the discharge of the electrolyte in the electrolytic cell is detected by a sensor 25 and the impression of the minute voltage by the second relay circuit 28 is also stopped.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、電解槽において陰極から陽極へ流れる逆電流
を防止する方法および装置に関する。　　勢〔従来の技
術〕 一般に、各種溶液の電解（例えば海水電解、塩水電解等
）は従来、第４図に示すような方法で行なわれている。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for preventing reverse current flowing from a cathode to an anode in an electrolytic cell. [Prior Art] In general, electrolysis of various solutions (for example, seawater electrolysis, saltwater electrolysis, etc.) is conventionally performed by a method as shown in FIG.

同図において、電解液は電解液供給管１を通うて電解槽
２へ入り、整流器６から電解用直流電圧が印加された陽
極３と陰極４との藺で電解され、電解液排出管５を通し
て次の工程へと送られる。この時の電流は、整流器６か
ら通電線７を通り、陽極３から電解液を通して陰極４へ
流れ、通電線８を介して整流器６へ戻る経路をたどる。In the figure, the electrolyte enters the electrolytic cell 2 through an electrolyte supply pipe 1, is electrolyzed between an anode 3 and a cathode 4 to which a DC voltage for electrolysis is applied from a rectifier 6, and passes through an electrolyte discharge pipe 5. Sent to the next process. At this time, the current flows from the rectifier 6 through the current-carrying line 7, from the anode 3 through the electrolyte to the cathode 4, and returns to the rectifier 6 via the current-carrying line 8.

ところで、このような電解装置の性能を判断する上で基
礎となる性能項目として、 ■　陽極３および陰極４での消費電力、■　陽極の電流
効率、電位、寿命、 等が挙げられるが、特に陽極の性能は電解装置の性能を
大きく左右する。By the way, the performance items that are the basis for determining the performance of such an electrolyzer include: ■ Power consumption at the anode 3 and cathode 4, ■ Current efficiency, potential, and lifespan of the anode, but especially the anode The performance of the electrolyzer greatly influences the performance of the electrolyzer.

従来、これら電解に使用されている陽極の主流は、電気
メッキによるＴｉ−Ｐｔ合金電極であったが、最近では
省エネルギー、省コスト型１１１１として薄膜型酸化物
電極が主流となりつつある。このｆｉｌｌ型酸化型置化
物電極た陽極は、一般にＤＳＡ　（寸法安定、性アノー
ド）と呼ばれ、Ｔｉを基材としてその上にＰｔ、Ｉｒ、
Ｒｕ、Ｐｄ等の貴金属に少量の卑金属を混入させたもの
を塗布・焼成して形成される。これらのＤＳＡをＴｉ−
ｐｔ合金電極と比較すると、電気的特性（Ｎ流動率、陽
極電位等）が特に優れている。Conventionally, the mainstream of anodes used for these electrolysis have been Ti--Pt alloy electrodes formed by electroplating, but recently thin film type oxide electrodes have become mainstream as energy-saving and cost-saving types 1111. This fill-type oxidized compound anode is generally called a DSA (dimensionally stable anode), and is made of Ti as a base material with Pt, Ir,
It is formed by coating and firing a precious metal such as Ru or Pd mixed with a small amount of base metal. Ti-
Compared to PT alloy electrodes, it has particularly excellent electrical properties (N flow rate, anode potential, etc.).

（発明が解決しようとする問題点〕 しかしながら、ＤＳＡの特性の研究が進につれて、最近
、通電をしないままの状態で陽極を電解液中に浸漬して
おくと、陽極単独での腐蝕や、陽極と陰極との電位差に
よって生じる逆電流のために酸化物金属の還元が起り、
電極消耗量を増大させる等の問題が発生することが明ら
かとなった。(Problems to be Solved by the Invention) However, as research on the characteristics of DSA has progressed, it has recently become clear that if the anode is immersed in an electrolyte without energizing, the anode alone may be corroded or Reduction of the oxide metal occurs due to the reverse current generated by the potential difference between the oxide and the cathode,
It has become clear that problems such as increased electrode consumption occur.

特に、一枚の電極基材上に陽極および陰極が存在する電
極や、陽極および陰極を短絡させた場合の陽極塗布物の
消耗量は急激に増加する。以下、この問題につい図を用
いて詳細に説明する。In particular, when an anode and a cathode are present on a single electrode base material or when the anode and cathode are short-circuited, the amount of consumption of the anode coating increases rapidly. This problem will be explained in detail below using figures.

［１）　　ｌ１ｊｉ極単独での腐蝕 第５図（ａ）（ｂ）に陽極を単独で電解液中に浸漬した
場合の状態を示す。第５図（ａ）は通電初期の状態を示
したもので、陽極３が電解液９中に浸された状態である
。陽極３はチタン等の電極基材１ｏと金属酸化物膜１１
からなっている。ここで、金属酸化物Ｉｌ！１１に含ま
れている各種金属酸化物をＭｌ、Ｍ２　、Ｍｌとすると
、これら金属酸化物は固溶一体化しているため、電解液
９と接した面上での電位差はそれ程大きくなく、腐蝕は
進行しにくいと考えてよい。[1] Corrosion of the l1ji electrode alone Figures 5(a) and 5(b) show the state when the anode alone is immersed in the electrolyte. FIG. 5(a) shows the state at the initial stage of energization, in which the anode 3 is immersed in the electrolytic solution 9. The anode 3 includes an electrode base material 1o such as titanium and a metal oxide film 11.
It consists of Here, the metal oxide Il! Assuming that the various metal oxides contained in 11 are Ml, M2, and Ml, these metal oxides are integrated as a solid solution, so the potential difference on the surface in contact with the electrolytic solution 9 is not so large, and corrosion does not occur. It can be considered difficult to progress.

ところが、通電日数の経過に伴って第５図（ｂ）に示し
たような消耗部分１２．１３ができると、金属酸化物１
１１１１の表面電位は消耗していない部分と消耗した部
分とで差が生じる。これはＮｓ。However, as the number of days of energization passes, a consumable part 12.13 as shown in FIG. 5(b) is formed, and the metal oxide 1
There is a difference in the surface potential of 1111 between the undepleted portion and the depleted portion. This is Ns.

Ｍ２．Ｍｓの性能に差があり、通電に伴う消耗量に差が
生じるためである。ここで、通電に対する腐蝕性の順位
をＭｌ　＞Ｍ２　＞Ｍｌとし、金属酸化物膜単独での電
位の序列を、 Ｍｌ　＞Ｍ２　＞Ｍｌ （貴）←→（卑） とすれば、消耗部分１２．１３と未消耗部分との間の電
位差は、第５図（ａ）の場合より大きくなり、腐蝕電流
の入り込む部分（真の部分）は還元電流のために消耗す
る。M2. This is because there is a difference in the performance of Ms, which causes a difference in the amount of consumption due to energization. Here, if the order of corrosiveness with respect to energization is Ml > M2 > Ml, and the order of potential of the metal oxide film alone is Ml > M2 > Ml (noble)←→(base), then the consumable portion 12. The potential difference between 13 and the unconsumed portion becomes larger than in the case of FIG. 5(a), and the portion into which the corrosive current enters (the true portion) is consumed due to the reduction current.

■　陽極および陰極が整流器を通して接続されている場
合の腐蝕 第４図に示したように、陽極２と陰極４間に整流器６が
接続された場合を考える。電解時の陽極３の電位をＥｌ
　、陰極４の電位をＥ２とすると、整流器６の電源を切
った時の陽極３および陰極４間には、 Ｅ−Ｅｌ　−Ｅ２　　（Ｅ２　＜０） の電圧負荷がある。すると、陰極４から陽極３へ逆電流
が流れ、陽極３の還元が生じる。この逆電流の大きさは
、整流器抵抗、電解液抵抗、電極面積に左右され、第６
図に示したような曲線となる。(2) Corrosion when the anode and cathode are connected through a rectifier As shown in FIG. 4, consider the case where a rectifier 6 is connected between the anode 2 and the cathode 4. The potential of the anode 3 during electrolysis is El
, when the potential of the cathode 4 is E2, there is a voltage load of E-El-E2 (E2 < 0) between the anode 3 and the cathode 4 when the power of the rectifier 6 is turned off. Then, a reverse current flows from the cathode 4 to the anode 3, and the anode 3 is reduced. The magnitude of this reverse current depends on the rectifier resistance, electrolyte resistance, and electrode area.
The curve will look like the one shown in the figure.

また、この曲線はＡ、Ｂ、Ｃの３つの領域に区分できる
。Ｃの領域は陽極３と陰極４の自然電位の差によって生
じる逆電流である。こうして発生する逆電流（還元電流
）によって、陽ｆｆ１３が消耗する。Further, this curve can be divided into three regions, A, B, and C. Region C is a reverse current caused by the difference in natural potential between the anode 3 and the cathode 4. The positive FF13 is consumed by the reverse current (reduction current) generated in this way.

（３）陽極および陰極を短絡した時、または一枚の基材
上に陽極および陰極が存在する場合第７因（ａ）に陽極
３および陰極４を短絡した場合、同図（ｂ）（ｃ）に一
枚の基材上に陽極３および陰極４が存在している状態を
示す。第７図（ａ）において、陽極３と陰極４とはリー
ド線１４によって短絡されている。第７図（ｂ）は一枚
のチタン基材の表裏両面にそれぞれ陽極１０および陰極
１１が形成された電極を電解液９に浸した状態を示した
もので、同図（Ｃ）は一枚のチタン基材１５の同一面上
に陽極部１６と陰極部１７が存在する電極を電解液９中
に浸した状態を示したものである。(3) When the anode and the cathode are short-circuited, or when the anode and the cathode are present on one substrate If the anode 3 and the cathode 4 are short-circuited due to factor 7 (a), the same figure (b) (c) ) shows a state in which an anode 3 and a cathode 4 are present on one base material. In FIG. 7(a), the anode 3 and the cathode 4 are short-circuited by a lead wire 14. In FIG. FIG. 7(b) shows a state in which electrodes having an anode 10 and a cathode 11 formed on the front and back surfaces of a single titanium base material are immersed in an electrolyte 9, and FIG. 7(C) shows a single titanium base material. This figure shows a state in which an electrode having an anode part 16 and a cathode part 17 on the same surface of a titanium base material 15 is immersed in an electrolytic solution 9.

これら第７図（ａ）（ｔ））（Ｃ）の３状態を、前記（
２）の整流器を介して陽極および陰極間を接続した状態
と比較すると、整流器の抵抗がない分だけ単位時間内に
流れる逆電流は大きくなる。第８図に第７図（ａ）の状
態においての逆電流と、整流器の出力電源を切った時か
らの経過時間との関係を示す。These three states of FIG. 7(a),(t))(C) are
Compared to the state of 2) in which the anode and cathode are connected via a rectifier, the reverse current flowing within a unit time becomes larger due to the lack of resistance of the rectifier. FIG. 8 shows the relationship between the reverse current in the state of FIG. 7(a) and the elapsed time since the output power of the rectifier was turned off.

次に、前記（１）〜（３の状！！Ｉ（第４図、第５図お
よび第７図参照）の各状態で、電極の電気的特性および
消耗量がどのように変化するかを、以下に示す試験条件
および方法で試験を行なって調査した。Next, we will examine how the electrical characteristics and consumption of the electrode change in each of the states (1) to (3) (see Figures 4, 5, and 7). The investigation was conducted using the following test conditions and methods.

陽極面積＝３０履Ｘ４０ｍ（Ｐｔ、Ｐｄ主成分）電解液
：＊水 電解液温度：２５℃前後 電流密度：　１５Ａ／ｄ７ｙＬ２ 整流器出力電源を切った時間：１ｌ−１０ｕｒ整流器出
力電源を切る頻度：１回／　ｄａｙ電解液流速：　０．
１　ｍ／Ｓｅｃ 試験方法：　１５Ａ／ｄｍ２で通電を行ない、１回／ｄ
ａＶ　Ｘ　１　Ｈｏｕｒだけ電源を切る。Anode area = 30 feet x 40 m (Pt, Pd main components) Electrolyte: * Water Electrolyte temperature: Around 25℃ Current density: 15A/d7yL2 Rectifier output power off time: 1l-10ur Rectifier output power off frequency: 1 Times/day Electrolyte flow rate: 0.
1 m/Sec Test method: energize at 15 A/dm2, 1 time/d
Turn off the power for aV x 1 Hour.

この試験の結果得られた、消耗量と電源を切った回数と
の関係を第９図に、電流効率と電源を切った回数との関
係を第１０図に、陽極電位と電源を切った回数との関係
を第１１図にそれぞれ示す。Figure 9 shows the relationship between the amount of consumption and the number of times the power was turned off, and Figure 10 shows the relationship between the current efficiency and the number of times the power was turned off. The relationships between the two are shown in FIG. 11.

なお、電源を切った回数は、６２回でストップした。Note that the number of times the power was turned off stopped at 62 times.

これら第９図〜第１１図において、曲線■は通電だけの
場合、曲線■は陽極単独での腐蝕、曲線■は陽極と陰極
が整流器を介して接続されている場合、曲線■は陽極と
陰極間を短絡した場合の変化をそれぞれ示している。曲
線■は６２回の短絡で７５％消耗し、電流効率は初期で
９７％程度あったのが８０％となり、また電位は１．１
８Ｖであったのが１．５Ｖ程度まで上昇した。In these Figures 9 to 11, the curve ``■'' is when only energization is applied, the curve ``■'' is the corrosion of the anode alone, the curve ``■'' is the case where the anode and the cathode are connected through a rectifier, and the curve ``■'' is the case where the anode and the cathode are connected. The graphs show the changes when the two are short-circuited. Curve ■ is consumed by 75% after 62 short circuits, the current efficiency has decreased from about 97% at the beginning to 80%, and the potential has decreased to 1.1.
The voltage rose from 8V to around 1.5V.

このように陽極の性能低下が生じると、次の問題が発生
する。When the performance of the anode is degraded in this way, the following problem occurs.

（ａ）　　電流効率の低下および電位の上昇に伴い、ラ
ンニングコストが増大する。(a) Running costs increase as current efficiency decreases and potential increases.

（ｂ）　　消耗量の増加により電極寿命が短くなる。(b) The electrode life will be shortened due to increased consumption.

各種電解槽において、電解の種類によってやや異なるが
、電解液を入れたままの状態で電解を中断する頻度は多
く、上記問題の解決は急務となっている。In various electrolytic cells, although it differs slightly depending on the type of electrolysis, electrolysis is often interrupted while the electrolyte remains in the tank, and there is an urgent need to solve the above problem.

本発明は上記した事情に鑑みてなされたもので、陰極か
ら陽極への逆電流の発生を防止し、逆電流′に起因する
ランニングコストの増加および電極消耗量の増加を抑制
することを可能とした電解槽における逆電流の防止方法
および装置を提供することを目的とする。The present invention has been made in view of the above-mentioned circumstances, and is capable of preventing the generation of reverse current from the cathode to the anode, and suppressing the increase in running costs and electrode consumption caused by reverse current. An object of the present invention is to provide a method and device for preventing reverse current in an electrolytic cell.

（問題点を解決するための手段） 本発明に係る電解槽における逆電流防止方法は、陽極と
陰極が配された電解槽に電解液を導き、これら陽極およ
び陰極間に電解用直流電圧を印加することにより電解を
行なうに際し、前記電解用直流電圧が遮断された時、前
記陽極および陰極間に微小直流電圧を印加して陽極から
陰極へ微小電流を流すことにより、陰極から陽極へ流れ
る逆電流を防止することを特徴とする。(Means for Solving the Problems) The method for preventing reverse current in an electrolytic cell according to the present invention is to introduce an electrolytic solution into an electrolytic cell in which an anode and a cathode are arranged, and apply a DC voltage for electrolysis between the anode and the cathode. When performing electrolysis, when the DC voltage for electrolysis is cut off, a minute DC voltage is applied between the anode and the cathode to cause a minute current to flow from the anode to the cathode, thereby creating a reverse current flowing from the cathode to the anode. It is characterized by preventing

また、本発明に係る電解槽における逆電流防止装置は、
陽極と陰極が配された電解槽に電解液を導き、これら陽
極および陰極間に電解用直流電圧を印加することにより
電解を行なう装置において、前記電解用直流電圧が遮断
された時１．前記陽極および陰極間に微小直流電圧を印
加して陽極から陰極へ微小電流を流す手段と、前記電解
槽の前記陽極および陰極より下方に設置された液面セン
サと、この液面センサにより電解液の液面が検出された
時、前記電解用直流電圧と共に前記微小直流電圧を遮断
する手段とを備えたことを特徴とする。Further, the reverse current prevention device in the electrolytic cell according to the present invention is
In an apparatus that performs electrolysis by introducing an electrolytic solution into an electrolytic cell having an anode and a cathode and applying a DC voltage for electrolysis between the anode and cathode, when the DC voltage for electrolysis is cut off: 1. means for applying a minute DC voltage between the anode and cathode to flow a minute current from the anode to the cathode; a liquid level sensor installed below the anode and cathode of the electrolytic cell; The present invention is characterized by comprising means for cutting off the minute DC voltage together with the electrolytic DC voltage when the liquid level is detected.

〔作用〕[Effect]

本発明においては、電解用直流電圧が遮断され　。 In the present invention, the DC voltage for electrolysis is cut off.

た時、陽極および陰極間に微小直流電圧が印加されるこ
とにより、陽極から陰極へ向かう順電流が流れ、それに
よって陰極から陽極へ向かう逆電流の発生が防止される
。At this time, a minute DC voltage is applied between the anode and the cathode, so that a forward current flows from the anode to the cathode, thereby preventing the generation of a reverse current from the cathode to the anode.

〔発明の効果〕〔Effect of the invention〕

本発明によれば、電解槽における逆電流が防止されるこ
とにより、逆電流に起因するランニングコストの増加が
抑えられ、また電極（陽極）の消耗量を低減させること
ができ、電気的特性の劣化が少なくなる。According to the present invention, by preventing reverse current in the electrolytic cell, it is possible to suppress the increase in running costs caused by reverse current, reduce the amount of wear of the electrode (anode), and improve the electrical characteristics. Deterioration is reduced.

〔実施例〕〔Example〕

第１図を参照して本発明の第１の実施例を説明する。第
１図において、電解液が電解液供給管１を通って電解槽
２に入り、整流器６に通電線７゜８を介して接続され直
流電圧が印加された陽極３と陰極４との間で電解されて
、電解液排出管５から送り出される構成は、第４図に示
した従来装置と同様である。A first embodiment of the present invention will be described with reference to FIG. In FIG. 1, an electrolytic solution enters an electrolytic cell 2 through an electrolytic solution supply pipe 1, and is connected to a rectifier 6 via a current-carrying wire 7.8 between an anode 3 and a cathode 4 to which a DC voltage is applied. The configuration in which the electrolyte is electrolyzed and sent out from the electrolyte discharge pipe 5 is the same as that of the conventional device shown in FIG.

ここで、本実施例においては整流器６と交流電源２０と
を接続している電気線路２１．２２に第１のリレー回路
２３が挿入され、この第１のリレー回路２３には電気線
路２４を介して、フロートレススイッチ等を含む液面セ
ンサ２５が接続されている。液面センサ２５は電解槽２
の陽極３および陰極４の設置位置より下方に設置され、
電解槽２内の液面を検出する。Here, in this embodiment, the first relay circuit 23 is inserted into the electric lines 21 and 22 connecting the rectifier 6 and the AC power supply 20, and the first relay circuit 23 is connected to the electric line 24. A liquid level sensor 25 including a floatless switch and the like is connected. The liquid level sensor 25 is connected to the electrolytic tank 2
is installed below the installation position of the anode 3 and cathode 4,
The liquid level in the electrolytic cell 2 is detected.

整流器６には第２図に示すように、電解用スイッチ２７
の他に該スイッチ２７に電気線路２７を介して接続され
た第２のリレー回路２８が備えられており、この第２の
リレー回路２８によって電解用直流電圧の遮断時に微小
直流電圧が出力される。As shown in FIG. 2, the rectifier 6 is equipped with an electrolysis switch 27.
In addition, a second relay circuit 28 connected to the switch 27 via an electric line 27 is provided, and this second relay circuit 28 outputs a minute DC voltage when the DC voltage for electrolysis is interrupted. .

今、電解用スイッチ２６を切り、電解用直流電圧を遮断
すると、同時に第２のリレー回路２８が働き、陽極３と
陰極４間に電解用直流電圧より小さい微小直流電圧が印
加され、通電ＩＩ７〜陽極３〜陰極４〜通電線８の経路
で微小電流が流れる。Now, when the electrolytic switch 26 is turned off and the electrolytic DC voltage is cut off, the second relay circuit 28 is activated at the same time, and a minute DC voltage smaller than the electrolytic DC voltage is applied between the anode 3 and the cathode 4, and the energization II7~ A minute current flows in the path from the anode 3 to the cathode 4 to the current-carrying wire 8.

これにより陰極４から陽極３へ向かう逆電流の発生が防
止される。This prevents generation of a reverse current flowing from the cathode 4 to the anode 3.

こうして電解が中断された後、電解槽２内の電解液が排
出され、電解液の液面が液面センサ２５で検出されると
、第１のリレー回路がオフ状態とされることにより、交
流電Ｉｔ！２０から整流器６への電源供給は遮断される
。従って、第２のリレー回路２８による微小直流電圧の
印加も、電解液の排出に伴って中断されることになる。After electrolysis is interrupted in this way, when the electrolytic solution in the electrolytic cell 2 is discharged and the liquid level of the electrolytic solution is detected by the liquid level sensor 25, the first relay circuit is turned off and the AC current is turned off. It! The power supply from 20 to rectifier 6 is cut off. Therefore, the application of the minute DC voltage by the second relay circuit 28 is also interrupted as the electrolyte is discharged.

上記構成において、海水を電解液として作動させ、前述
の従来法について行なった試験と同様の条件および方法
で試験を行ない、陽極の消耗量と電気的性能の変化を調
べた。下表にその結果を示す。With the above configuration, a test was conducted using seawater as the electrolyte under the same conditions and method as the test conducted for the conventional method described above, and the amount of consumption of the anode and changes in electrical performance were investigated. The results are shown in the table below.

表 陽極消耗量（％）　電流効率（％）　電位（Ｖ）４０　
　　　　　　９７　　　　１．１８ただし、上記表中の
値は１００回電源を切った後の計測値である。Surface anode consumption (%) Current efficiency (%) Potential (V) 40
97 1.18 However, the values in the above table are the values measured after turning off the power 100 times.

この結果からも明らかなように、陽極の消耗はほとんど
皆無であり、電気的特性の劣化も起こっでいない。As is clear from this result, there was almost no consumption of the anode, and no deterioration of the electrical characteristics occurred.

このように本発明に基づいて電解の中断と同時に陽極か
ら陰極へ微小電流を流すことによる効果をまとめると、
次のようになる。In summary, the effects of flowing a minute current from the anode to the cathode at the same time as the interruption of electrolysis based on the present invention are as follows:
It will look like this:

（１）　　陽極と陰極間の短絡による陽極の消耗をはと
んと皆無にすることができる。(1) Anode wear due to short circuits between the anode and cathode can be completely eliminated.

（２電気的特性の劣化が防止される。(2) Deterioration of electrical characteristics is prevented.

［３）　　（１）（２）の結果、ランニングコストの上
昇、さらにイニシャルコストの増加が抑制される。[3] As a result of (1) and (2), increases in running costs and further increases in initial costs are suppressed.

次に、第３図を参照して本発明の第２の実施例を説明゛
する。本実施例においては、整流器６を電解用とし、そ
の他にもう一つ微小直流電圧印加用としての整流器３ｏ
が設けられている。整流器６からの電解用直流電圧の出
力が遮断されると、同時に電気線路３１を介して結合さ
れている第１のリレー回路２３と第３のリレー回路３２
が働き、整流器３０の入出力がオン状態となることによ
って、前述と同様に陽極３から陰極４へと微小電流が流
れ、逆電流の発生が防止される。また、電解槽２内の電
解液がなくなると、第１の実施例と同様にして液面セン
サ２５でそれが検出され、整流器３０の入力が遮断され
、微小電流の供給も中断される。従って、本実施例にお
いても第１の実施例と同様の効果を得ることができる。Next, a second embodiment of the present invention will be explained with reference to FIG. In this embodiment, the rectifier 6 is used for electrolysis, and another rectifier 3o is used for applying a minute DC voltage.
is provided. When the output of the electrolytic DC voltage from the rectifier 6 is cut off, the first relay circuit 23 and the third relay circuit 32 which are connected via the electric line 31 simultaneously
is activated, and the input and output of the rectifier 30 are turned on, so that a minute current flows from the anode 3 to the cathode 4 in the same manner as described above, and generation of a reverse current is prevented. Furthermore, when the electrolytic solution in the electrolytic cell 2 runs out, it is detected by the liquid level sensor 25 in the same manner as in the first embodiment, the input to the rectifier 30 is cut off, and the supply of minute current is also interrupted. Therefore, in this embodiment as well, the same effects as in the first embodiment can be obtained.

なお、本発明は上記した実施例に限定されるものではな
く、その要旨を逸脱しない範囲で種々変形して実施が可
能である。例えば陽極および陰極が同一基材上に形成さ
れた電極では、第１および第２の実施例で説明したよう
に微小電流を流すための微小直流電圧発生手段としては
整流器が好適であるが、陽極と陰極とが別々の基材上形
成されている電解装置においては、陽極と陰極との電位
差よりも若干高い程度の直流電圧を印加するものであれ
ばよく、必ずしも整流器を使用する必要はない。Note that the present invention is not limited to the embodiments described above, and can be implemented with various modifications without departing from the gist thereof. For example, in the case of an electrode in which an anode and a cathode are formed on the same base material, a rectifier is suitable as a means for generating a minute DC voltage to flow a minute current as explained in the first and second embodiments. In an electrolytic device in which a cathode and a cathode are formed on separate base materials, it is sufficient to apply a DC voltage slightly higher than the potential difference between the anode and cathode, and it is not necessarily necessary to use a rectifier.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本発明の第１の実施例に係る電解装置の概略構
成図、第２図は同実施例における整流器の内部構成を示
す図、第３図は本発明の第２の実施例に係る電解装置の
要部の概略構成画、第４図は従来の電解装置の一例を示
す図、第５図（ａ）（ｂ）は電解液中に浸漬中の未消耗
陽極および消耗陽極の図、第６図は整流器を介して陰極
から陽極へ流れる逆電流の経時変化を示す図、第７図（
ａ）は陽極と陰極間を短絡して電解液中に浸漬した状態
を示す図、第７図（ｂ）（Ｃ）は一枚の基材上に陽極と
陰極が形成されている電極を電解液中に浸漬した状態を
示す図、第８図は整流器出力電源を切ると同時に陽極と
陰極間を短絡した時に流れる逆電流の経時変化を示す図
、第９図は整流器の電源を１回／ｄａＶ　Ｘ　Ｈｏｕｒ
の割合で切った時の陽極酸化物消耗量の電源を切った回
数に対する変化を示す図、第１０図は陽極の電流効率の
整流器出力電源を切った回数に伴う変化を示す図、第１
１図は陽極の電位の整流器出力電源を切った回数に伴う
変化を示す図である。 １・・・電解液供給管、２・・・電解槽、３・・・陽極
、４・・・陰極、５・・・電解液排出管、６・・・整流
器、７．８・・・通電線、１０・・・電極基材、１１・
・・金属酸化物膜、１２．１３・・・消耗部分、１４・
・・短絡線、１５・・・電極基材、１６・・・陽極部、
１７・・・陰極部、２０・・・交流ｆ！ｌ！Ｉ、２１．
２２・・・電気線路、２３・・・リレー回路、２４・・
・電気線路、２５・・・液面センサ、２６・・・電解用
スイッチ、２７・・・電気線路、２８・・・リレー回路
、３０・・・整流器、３１・・・電気線路、３２・・・
リレー回路・。 出願人復代理人　弁理士　鈴江武彦 第１図 す 第２図 第３図 第４図 第５図 第６図 、＋−一　　　　　−へ Ｊ　　　　　　　−一−−〆− （ａ） 第７図 第８図 第９図 第１０図FIG. 1 is a schematic configuration diagram of an electrolytic device according to a first embodiment of the present invention, FIG. 2 is a diagram showing the internal configuration of a rectifier in the same embodiment, and FIG. A schematic diagram of the main parts of such an electrolytic device; FIG. 4 is a diagram showing an example of a conventional electrolytic device; FIGS. 5(a) and 5(b) are diagrams of an unconsumable anode and a consumable anode immersed in an electrolytic solution. , Figure 6 is a diagram showing the change over time of the reverse current flowing from the cathode to the anode via the rectifier, and Figure 7 (
Figure 7 (b) and (C) show the state in which the anode and cathode are short-circuited and immersed in an electrolytic solution. Figure 8 shows the state in which the rectifier is immersed in the liquid. Figure 8 shows the change over time in the reverse current that flows when the anode and cathode are short-circuited at the same time as the rectifier output power is turned off. Figure 9 shows the state in which the rectifier output is turned off and the anode and cathode are short-circuited. daV X Hour
Figure 10 is a diagram showing the change in anode oxide consumption with the number of times the power is turned off when the power is turned off at a rate of .
FIG. 1 is a diagram showing a change in the potential of the anode with the number of times the rectifier output power is turned off. DESCRIPTION OF SYMBOLS 1... Electrolyte supply pipe, 2... Electrolytic cell, 3... Anode, 4... Cathode, 5... Electrolyte discharge pipe, 6... Rectifier, 7.8... Connection Electric wire, 10... Electrode base material, 11.
...Metal oxide film, 12.13...Consumable part, 14.
... Short circuit wire, 15 ... Electrode base material, 16 ... Anode part,
17...Cathode part, 20...AC f! l! I, 21.
22... Electric line, 23... Relay circuit, 24...
・Electric line, 25... Liquid level sensor, 26... Electrolysis switch, 27... Electric line, 28... Relay circuit, 30... Rectifier, 31... Electric line, 32...・
Relay circuit. Applicant Sub-Agent Patent Attorney Takehiko Suzue Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6, +-1 -J -1--〆- (a) Figure 7 Figure 8 Figure 9 Figure 10

Claims (2)

【特許請求の範囲】[Claims] （１）陽極と陰極が配された電解槽に電解液を導き、こ
れら陽極および陰極間に電解用直流電圧を印加すること
により電解を行なうに際し、前記電解用直流電圧が遮断
された時、前記陽極および陰極間に微小直流電圧を印加
して、陽極から陰極に微小電流を流すことにより、陰極
から陽極へ流れる逆電流を防止することを特徴とする電
解槽における逆電流の防止方法。(1) When conducting electrolysis by introducing an electrolytic solution into an electrolytic cell in which an anode and a cathode are arranged and applying a DC voltage for electrolysis between these anodes and cathodes, when the DC voltage for electrolysis is interrupted, the A method for preventing reverse current in an electrolytic cell, characterized in that reverse current flowing from the cathode to the anode is prevented by applying a minute DC voltage between the anode and the cathode and causing a minute current to flow from the anode to the cathode. （２）陽極と陰極が配された電解槽に電解液を導き、こ
れら陽極および陰極間に電解用直流電圧を印加すること
により電解を行なう装置において、前記電解用直流電圧
が遮断された時、前記陽極および陰極間に微小直流電圧
を印加して、陽極から陰極へ微小電流を流す手段と、前
記電解槽の前記陽極および陰極より下方に設置された液
面センサと、この液面センサにより電解液の液面が検出
された時、前記電解用直流電圧と共に前記微小直流電圧
を遮断する手段とを備えたことを特徴とする電解槽にお
ける逆電流の防止装置。(2) In a device that performs electrolysis by introducing an electrolytic solution into an electrolytic cell in which an anode and a cathode are arranged and applying a DC voltage for electrolysis between the anode and the cathode, when the DC voltage for electrolysis is cut off, means for applying a minute DC voltage between the anode and cathode to flow a minute current from the anode to the cathode; a liquid level sensor installed below the anode and cathode of the electrolytic cell; A device for preventing reverse current in an electrolytic cell, comprising means for cutting off the minute DC voltage together with the electrolysis DC voltage when the liquid level of the liquid is detected.