JPH0160552B2 - - Google Patents

Info

Publication number
JPH0160552B2
JPH0160552B2 JP5272882A JP5272882A JPH0160552B2 JP H0160552 B2 JPH0160552 B2 JP H0160552B2 JP 5272882 A JP5272882 A JP 5272882A JP 5272882 A JP5272882 A JP 5272882A JP H0160552 B2 JPH0160552 B2 JP H0160552B2
Authority
JP
Japan
Prior art keywords
detection electrode
iron ion
iron
ion implantation
change
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
JP5272882A
Other languages
Japanese (ja)
Other versions
JPS58171578A (en
Inventor
Mitsuyuki Abe
Kenji Oonishi
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.)
Nippon Corrosion Engineering Co Ltd
Original Assignee
Nippon Corrosion Engineering Co Ltd
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 Nippon Corrosion Engineering Co Ltd filed Critical Nippon Corrosion Engineering Co Ltd
Priority to JP5272882A priority Critical patent/JPS58171578A/en
Publication of JPS58171578A publication Critical patent/JPS58171578A/en
Publication of JPH0160552B2 publication Critical patent/JPH0160552B2/ja
Granted legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23FNON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F11/00Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
    • C23F11/08Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
    • C23F11/18Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids using inorganic inhibitors

Landscapes

  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Prevention Of Electric Corrosion (AREA)
  • Preventing Corrosion Or Incrustation Of Metals (AREA)

Description

【発明の詳細な説明】[Detailed description of the invention]

この発明は、鉄イオン注入監視装置の提供に係
わる。 海水を用いた熱交換器には銅合金チユーブを使
用しているが、当該チユーブの潰食防止の方法と
して鉄イオン注入が有効な方法として実施されて
いる。 すなわち、一般に、銅合金部材の耐食性は表面
に形成される保護皮膜によつて左右されるが、そ
の中でも特に耐食性能の向上に重要な役割りをも
つものが鉄系の保護皮膜であることが知られ、特
に、冷却管内の防食に対しては、在来の電気防食
法と併用することにより管端部だけでなく管内面
全体の防食効果が期待でき、また電気防食の所要
防食電流の低減も計れることから、この種の併用
が広く実施される傾向にある。鉄系保護皮膜を形
成する鉄イオンの注入法としては硫酸第1鉄や鉄
電解槽が用いられる。 しかるに、これら防食法を実施する場合、その
保護皮膜の維持、管理は重要であり防食状況が明
確に確認でき適正な供給を継続させる手段が必要
である。 従来、鉄イオン供給法における防食状況の確認
は一定期間鉄イオンを供給した後に冷却管を引き
抜きその一部を切り取るか、あらかじめ水室内に
設置した試験片を取り出して表面に形成された防
食保護皮膜の状態を観察しその成分を分析するな
どの方法によるため、その判断には時間的な制約
をうけるとともに多大の手間ひまを必要としてい
た。 そこで、銅合金部材表面に形成される防食保護
皮舶の分極抵抗値と皮膜状態との間に下表のよう
な関係の経験側を基にして、
The present invention relates to providing an iron ion implantation monitoring device. Copper alloy tubes are used in heat exchangers using seawater, and iron ion implantation is an effective method for preventing erosion of the tubes. In other words, the corrosion resistance of copper alloy members is generally influenced by the protective film formed on the surface, but it is the iron-based protective film that plays a particularly important role in improving corrosion resistance. In particular, for corrosion protection inside cooling pipes, when used in conjunction with conventional cathodic protection methods, corrosion protection effects can be expected not only on the pipe ends but also on the entire inner surface of the pipe, and the required corrosion protection current for cathodic protection can be reduced. This type of combination tends to be widely implemented because it can also be used to measure As a method for implanting iron ions to form an iron-based protective film, ferrous sulfate or an iron electrolytic bath is used. However, when implementing these anti-corrosion methods, it is important to maintain and manage the protective film, and a means to clearly confirm the anti-corrosion status and continue appropriate supply is required. Conventionally, the corrosion protection status in the iron ion supply method was confirmed by supplying iron ions for a certain period of time, then pulling out the cooling pipe and cutting a part of it, or by taking out a test piece that had been placed in a water chamber in advance and forming an anticorrosion protective film on the surface. Since the method involves observing the state of the substance and analyzing its components, the determination is subject to time constraints and requires a great deal of time and effort. Therefore, based on the empirical relationship between the polarization resistance value of the anti-corrosion protective coating formed on the surface of the copper alloy member and the coating condition as shown in the table below,

【表】 上記分極抵抗値をプラント運転中において簡単
に計測することにより銅合金部材の防食皮膜の状
態を管理する、すなわち、電気防食装置の電流回
路と電位計測装置を用い防食電流Oのときの陰極
(銅合金部材)電位および防食電流供給時の陰極
(銅合金部材)電位とを通電々流値をあらかじめ
銅合金部材への防食電流配分比率と防食対象面積
とを記憶させた演算回路に入力し、単位面積当り
の皮膜(分極)抵抗値を算出して、これから上記
関係に基づき防食皮膜の状態を把握するとした手
段が提案されている。 しかるに、これは、一見適格かつ合理的なよう
であるが、重大な誤差要因をもつている。 すなわち、上述の如く電気防食装置の電流回路
を利用して測定された皮膜抵抗値は、当該皮膜の
形成状態に関係なく回路の一部を構成の海水の水
温、水質等の外部条件で変化するためにその皮膜
評価は必らずしも適正でない難点がある。 本発明は叙上の事情に鑑みなされたもので、か
かる不適正要因を是正した新規手段を提供するも
のである。 すなわち、本発明は保護皮膜の形成状態を水室
と取水路に配設した検出電極によつて検知し、電
気的に外部警報として表示し、適正注入時期を指
示するとしたもので、つまり、熱交換器の水室、
管板および冷却管内と鉄イオン注入前の海水取水
路に単独又は複数の検出電極を設け、熱交換器側
検出電極に形成される鉄イオンによる電極表面の
皮膜と汚れによる分極抵抗の変化と取水路検出電
極の汚れによる分極抵抗の変化の大きさを電気的
に比較して変化量に応じて適正な鉄イオン注入を
外部に表示する装置である。第1図は本発明装置
の概略を示し、水室内に検出電極2および水路内
に検出電極3を設置し、各々の絶縁電線を鉄イオ
ン監視装置1に接続する。 当該監視装置1の信号は盤面や中央電気管理室
に表示可能とし、且つ、現場に設置される硫酸第
1鉄注入装置7や鉄電解槽8の制御信号として利
用できる。 該検出電極2,3は熱交換器の管板又は冷却管
の材質と同質とし、各々に取付ける電極形状は同
型とする。 尚、検出電極2,3は単独又は複数とし、各々
を接続箱4にまとめて配線する。 図中5は熱交換器水室、6は循環水ポンプ、9
は海水取水路を夫々示す。 又、第2図は叙上本発明装置の計測部の概略を
示す。各検出電極2,3及び2本の抵抗によるブ
リツジ回路の両端には矩形波発生装置10によつ
て電圧を加え、ブリツジ回路の残りの2端子を増
巾器11に接続して検出電極に形成される鉄イオ
ンによる皮膜の程度によつて変化する検出電圧を
増巾器11で増巾する。すなわち水室内の検出電
極2及び水路内の検出電極3には同じ電流が流れ
るが水室内の検出電極2には鉄イオンによる皮膜
形成によつて分極抵抗が増加するため分極量が大
きくなり両端の電圧は水路内の検出電極3より増
加してブリツジ回路の出力電圧が増加する。 検出電圧の大きさは皮膜形成の状態によつてあ
る基準巾を持たせることが必要のため、その調整
装置12,13を附属させる。つまり、12は基
準値と過剰値の調整、13は基準値と不足値の調
整である。 増巾した電圧は比較回路14に入れ、各々の検
出電極電流の大きさを対比させる。 比較回路14には基準値を変化させる調整器1
5と各電極設置場所の流速条件を修正する修正回
路16および複数の検出電極の平均値を算出する
演算回路17を附属させる。 外部表示の方法は装置盤面にランプ、メータ
ー、ベル等によつてなされたもので、図中18,
19,20は、注入過剰、注入適正、注入不足を
示す表示装置である。 その他、装置内に警報端子やコンピユーター端
子を設け、中央管理電気室に記号を送る外部管理
制御を可能とする。 尚、図中21は電源回路を示す。 第3図は、検出電圧の変化を示すもので、適正
基準、過剰値および不足値を表わす推定図
である。 しかして、叙上本発明装置によるならば、水室
内の検出電極2及び水路内の検出電極3の表面は
設置環境の相違によつて附着物が異なつてくる。 即ち、鉄イオンを注入している水室内電極2表
面には鉄皮膜が附着するが、水路内の電極3表面
には附着しない。 本発明では、鉄保護皮膜の評価は電気防食施工
の復水器実測から管板および管端部の表面抵抗の
大きさによつて判定している。 表面抵抗の大きさは新管および保護皮膜が充分
でない場合、1Ω―m2以下、適正な保護皮膜は1
〜20Ω―m2、過剰な保護皮膜20Ω―m2以上であ
る。 鉄イオン注入の管理制御法として管板および管
端部の表面抵抗を自動的に測定してその大きさを
表示するのも一つの方法であるが、この場合、季
節的に水温が変動することによる伝導率の変化、
夏季の水質汚染および冷却水量の変化等によつて
表面抵抗も保護皮膜の形成状態に関係なく変化す
る。そのため、表面抵抗の大きさは不正確になる
ので実用的でない。 また、検出電極を水室内に取付けるのも一つの
方法であるが、この場合も前述表面抵抗の方法と
同じように種々の条件が加わるので不正確になる
ので実用的でない。 ところが、本発明では、鉄イオン注入点以前の
熱交換器に用いる冷却水と同じ水路内に検出電極
を設置し、水室内の検出電極の表面に附着する鉄
イオンの量を各々の電極で比較し、附着する量の
大きさの変化を電気的に検知する方法であるの
で、この場合には、設置する検出電極の水質条件
が同一となり、水温、水質および伝導率の要素は
省略することが出来るので、正確な値を検出する
ことが可能となつている。 この結果、下記の如き諸効果が奏される。 (1) 従来、慣習として手動によつて硫酸第1鉄を
注入していたものが、保護皮膜の形成状態によ
つて自動的に注入時期を知ることが出来る。 (2) 鉄電解槽を用いている場合、保護皮膜の形成
状態によつて鉄イオンの発生量を自動的に制御
出来る。 また、本発明装置の利用例を例示するならば下
記の通りである。 (1) 火力発電所の復水器および冷却器の鉄イオン
注入管路を制御。 (2) 石油化学、石油製精工場の冷却器の鉄イオン
注入管理と制御。 (3) 舶用復水器および冷却器の鉄イオン注入管理
と制御。 (4) 鉄電解槽の鉄イオン発生量の管理と制御。
[Table] The state of the anti-corrosion coating on copper alloy members can be managed by simply measuring the above polarization resistance value during plant operation. The cathode (copper alloy member) potential and the cathode (copper alloy member) potential when the anticorrosive current is supplied are input to the arithmetic circuit that stores the anticorrosive current distribution ratio to the copper alloy member and the area to be protected in advance. However, a method has been proposed in which the coating (polarization) resistance value per unit area is calculated and the state of the anticorrosion coating is determined based on the above relationship. However, although this seems reasonable and reasonable at first glance, it has a serious error factor. In other words, as mentioned above, the film resistance value measured using the current circuit of the cathodic protection device changes depending on external conditions such as the temperature and quality of the seawater that constitutes part of the circuit, regardless of the state of formation of the film. Therefore, the film evaluation is not always appropriate. The present invention has been made in view of the above circumstances, and provides a new means for correcting such inappropriate factors. In other words, the present invention detects the formation state of the protective film using detection electrodes installed in the water chamber and the intake channel, and displays it electrically as an external alarm to indicate the appropriate injection time. exchanger water chamber,
A single or multiple detection electrodes are installed in the tube plate and cooling pipes and in the seawater intake channel before iron ion injection, and changes in polarization resistance due to a film and dirt on the electrode surface due to iron ions formed on the detection electrode on the heat exchanger side and water intake. This is a device that electrically compares the magnitude of change in polarization resistance due to contamination of the road detection electrode and externally indicates appropriate iron ion implantation according to the amount of change. FIG. 1 schematically shows the apparatus of the present invention, in which a detection electrode 2 is installed in a water chamber and a detection electrode 3 is installed in a water channel, and each insulated wire is connected to an iron ion monitoring device 1. The signal from the monitoring device 1 can be displayed on the panel or in the central electrical control room, and can also be used as a control signal for the ferrous sulfate injection device 7 and the iron electrolytic cell 8 installed at the site. The detection electrodes 2 and 3 are made of the same material as the tube plate or cooling pipe of the heat exchanger, and the shapes of the electrodes attached to each are the same. Incidentally, the detection electrodes 2 and 3 may be used alone or in plurality, and each of them is wired together in the connection box 4. In the figure, 5 is the heat exchanger water chamber, 6 is the circulating water pump, and 9
indicate seawater intake channels. Further, FIG. 2 schematically shows the measuring section of the apparatus of the present invention described above. A rectangular wave generator 10 applies voltage to both ends of a bridge circuit consisting of each detection electrode 2, 3 and two resistors, and the remaining two terminals of the bridge circuit are connected to an amplifier 11 to form a detection electrode. Amplifier 11 amplifies the detected voltage, which varies depending on the degree of coating formed by iron ions. In other words, the same current flows through the detection electrode 2 in the water chamber and the detection electrode 3 in the water channel, but the polarization resistance increases due to the formation of a film by iron ions on the detection electrode 2 in the water chamber, so the amount of polarization increases and the polarization at both ends increases. The voltage increases from the detection electrode 3 in the water channel, and the output voltage of the bridge circuit increases. Since the magnitude of the detection voltage needs to have a certain standard width depending on the state of film formation, adjusting devices 12 and 13 are attached. That is, 12 is the adjustment of the reference value and excess value, and 13 is the adjustment of the reference value and insufficient value. The amplified voltage is input to a comparison circuit 14 to compare the magnitude of each detection electrode current. The comparison circuit 14 includes a regulator 1 that changes the reference value.
5, a correction circuit 16 for correcting the flow velocity conditions at each electrode installation location, and an arithmetic circuit 17 for calculating the average value of a plurality of detection electrodes. The external display method is by using lamps, meters, bells, etc. on the device panel, and is indicated by 18 in the figure.
19 and 20 are display devices indicating excessive injection, appropriate injection, and insufficient injection. In addition, alarm terminals and computer terminals are installed inside the device to enable external management control by sending symbols to the central control electrical room. Note that 21 in the figure indicates a power supply circuit. FIG. 3 shows changes in the detected voltage, and is an estimated diagram showing appropriate standards, excessive values, and insufficient values. According to the device of the present invention described above, the surfaces of the detection electrode 2 in the water chamber and the detection electrode 3 in the waterway have different deposits depending on the installation environment. That is, the iron coating adheres to the surface of the electrode 2 in the water chamber into which iron ions are implanted, but does not adhere to the surface of the electrode 3 in the water channel. In the present invention, the iron protective coating is evaluated based on the magnitude of the surface resistance of the tube sheet and tube end based on actual measurements of the condenser during cathodic protection. The surface resistance is less than 1Ω-m2 for new pipes and when the protective film is insufficient, and for a proper protective film it is 1Ω- m2 or less.
~20Ω-m 2 , and the excess protective film is 20Ω-m 2 or more. One way to manage and control iron ion implantation is to automatically measure the surface resistance of tube sheets and tube ends and display its magnitude, but in this case, water temperature fluctuates seasonally. Change in conductivity due to,
The surface resistance also changes due to water pollution in summer and changes in the amount of cooling water, regardless of the state of formation of the protective film. Therefore, the magnitude of the surface resistance becomes inaccurate, which is not practical. Another method is to install the detection electrode inside the water chamber, but in this case as well, as with the surface resistance method, various conditions are added, making the method inaccurate and thus impractical. However, in the present invention, the detection electrode is installed in the same water channel as the cooling water used for the heat exchanger before the iron ion injection point, and the amount of iron ions attached to the surface of the detection electrode in the water chamber is compared for each electrode. However, since this is a method of electrically detecting changes in the amount of adhesion, the water quality conditions of the detection electrodes installed are the same, and the elements of water temperature, water quality, and conductivity can be omitted. This makes it possible to detect accurate values. As a result, the following effects are produced. (1) Conventionally, ferrous sulfate was injected manually, but now it is possible to automatically determine when to inject ferrous sulfate based on the state of the protective film formed. (2) When using an iron electrolytic cell, the amount of iron ions generated can be automatically controlled depending on the state of the protective film formed. Further, examples of usage of the device of the present invention are as follows. (1) Controls iron ion implantation lines for condensers and coolers in thermal power plants. (2) Iron ion implantation management and control of coolers in petrochemical and oil refineries. (3) Iron ion implantation management and control for marine condensers and coolers. (4) Management and control of the amount of iron ions generated in the iron electrolyzer.

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

第1図は本発明装置の概略図、第2図は同装置
の計測部の概略図、第3図は検出電流の変化図で
ある。 2,3…検出電極、1…鉄イオン監視装置、4
…接続箱、5…熱交換器水室、6…循環水ポン
プ、7…硫酸第1鉄注入装置、8…鉄電解槽、9
…海水取水路、10…矩形波発生装置、11…増
巾器、12,13…調整装置、14…比較回路、
15…調整器、16…修正回路、17…演算回
路、18,19,20…表示装置、21…電源回
路。
FIG. 1 is a schematic diagram of the device of the present invention, FIG. 2 is a schematic diagram of the measuring section of the device, and FIG. 3 is a diagram of changes in detected current. 2, 3...detection electrode, 1...iron ion monitoring device, 4
... Connection box, 5... Heat exchanger water chamber, 6... Circulating water pump, 7... Ferrous sulfate injection device, 8... Iron electrolytic cell, 9
... seawater intake channel, 10 ... square wave generator, 11 ... amplifier, 12, 13 ... adjustment device, 14 ... comparison circuit,
15... Adjuster, 16... Correction circuit, 17... Arithmetic circuit, 18, 19, 20... Display device, 21... Power supply circuit.

Claims (1)

【特許請求の範囲】[Claims] 1 熱交換器等の水室、管板および冷却管内と鉄
イオン注入前の海水取水路に単独又は複数の検出
電極を設け、該熱交換器側検出電極に形成される
鉄イオンによる電極表面の皮膜と汚れによる分極
抵抗の変化と該取水路検出電極の汚れによる分極
抵抗の変化の大きさを電気的に比較して変化量に
応じて適正な鉄イオン注入を外部に表示するとし
てなることを特徴とする在来の電気防食法と併用
する鉄イオン注入による潰食防止に於ける鉄イオ
ン注入監視装置。
1. A single or multiple detection electrode is provided in the water chamber, tube plate, and cooling pipe of a heat exchanger, etc., and in the seawater intake channel before iron ion injection, and the iron ions formed on the heat exchanger side detection electrode are used to detect the electrode surface. By electrically comparing the change in polarization resistance due to the film and dirt with the magnitude of the change in polarization resistance due to dirt on the intake channel detection electrode, it is possible to externally display appropriate iron ion implantation according to the amount of change. Features: Iron ion implantation monitoring device used in combination with conventional cathodic protection methods to prevent erosion by iron ion implantation.
JP5272882A 1982-03-31 1982-03-31 Device for monitoring injection of iron ion Granted JPS58171578A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5272882A JPS58171578A (en) 1982-03-31 1982-03-31 Device for monitoring injection of iron ion

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5272882A JPS58171578A (en) 1982-03-31 1982-03-31 Device for monitoring injection of iron ion

Publications (2)

Publication Number Publication Date
JPS58171578A JPS58171578A (en) 1983-10-08
JPH0160552B2 true JPH0160552B2 (en) 1989-12-22

Family

ID=12922980

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5272882A Granted JPS58171578A (en) 1982-03-31 1982-03-31 Device for monitoring injection of iron ion

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JPH0631816B2 (en) * 1986-10-03 1994-04-27 株式会社日立製作所 Method and apparatus for suppressing elution of radioactive material into cooling water in nuclear power plant
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