JP4013486B2 - Cooling water slime prevention method - Google Patents
Cooling water slime prevention method Download PDFInfo
- Publication number
- JP4013486B2 JP4013486B2 JP2001046409A JP2001046409A JP4013486B2 JP 4013486 B2 JP4013486 B2 JP 4013486B2 JP 2001046409 A JP2001046409 A JP 2001046409A JP 2001046409 A JP2001046409 A JP 2001046409A JP 4013486 B2 JP4013486 B2 JP 4013486B2
- Authority
- JP
- Japan
- Prior art keywords
- cooling water
- water
- residual chlorine
- slime
- chlorine
- 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 - Fee Related
Links
Images
Landscapes
- Treatment Of Water By Oxidation Or Reduction (AREA)
- Water Treatment By Electricity Or Magnetism (AREA)
Description
【０００１】
【発明の属する技術分野】
本発明は、冷却水系のスライム防止方法に関する。さらに詳しくは、本発明は、冷却水系において、金属部材の腐食を抑えて、しかもスライムの発生を効果的に防止することができる冷却水系のスライム防止方法に関する。
【０００２】
【従来の技術】
冷却水は、石油化学産業や鉄鋼産業などの種々の産業分野において、間接的又は直接的に被処理物を冷却する目的で、あるいは、ビルの空調、冷暖房、その関連装置などに多量に使用されている。近年は、水資源の不足や有効利用の観点から、冷却水の使用量を削減するために、開放循環冷却水系の高濃縮運転における強制ブロー量の削減など、冷却水の高度利用が行われている。このように冷却水を高度に利用した場合には、溶存塩類や栄養源の濃縮などにより、循環冷却水の水質が悪化し、細菌、黴、藻類などの微生物群に、土砂、塵埃などが混ざり合って形成されるスライムが発生しやすくなり、熱交換器における熱効率の低下や通水の悪化を引き起こし、またスライム付着下部において、機器や配管の局部腐食を誘発する。
そこで、このようなスライムによる障害を防止するために、種々の抗菌剤、例えば、次亜塩素酸ナトリウムや過酸化水素水などの酸化性抗菌剤などが用いられている。これらの抗菌剤は、薬剤タンクに貯留され、薬注ポンプによって冷却水系に注入されている。しかし、スライム防止のために抗菌剤を使用すると、ローリー運搬、コンテナ移動など、運搬に労力を要し、抗菌剤の取り扱い中に漏洩などを起こして人体に被害を与える危険性があり、抗菌剤の残量をチェックして定期的に補充する手間がかかるなどの問題がある。
冷却水系で問題となるスライム障害を防止するために、電解次亜塩素酸発生装置が用いられている。しかし、補給水中の塩化物イオン濃度が低い場合には、冷却水系において塩化物イオンが濃縮されても、スライム処理に十分な次亜塩素酸の発生速度が得られなかった。また、冷却水に食塩などを添加して塩化物イオン濃度を高めると、冷却水と接触する金属部材に腐食を生じやすくなるという問題があった。このために、金属部材の腐食を抑え、しかもスライムの発生を効果的に防止し得る冷却水系のスライム防止方法が求められていた。
【０００３】
【発明が解決しようとする課題】
本発明は、開放循環冷却水系において、金属部材の腐食を抑えて、しかもスライムの発生を効果的に防止することができる冷却水系のスライム防止方法を提供することを目的としてなされたものである。
【０００４】
【課題を解決するための手段】
本発明者らは、上記の課題を解決すべく鋭意研究を重ねた結果、開放循環冷却水系において、食塩水を電解し残留塩素を発生させた塩素水を補給水に添加し、さらに循環水系に電解槽を設置して残留塩素を発生させることにより、金属部材の腐食速度が小さく、しかもスライム防止に必要かつ十分な残留塩素の発生速度が得られることを見いだし、この知見に基づいて本発明を完成するに至った。
すなわち、本発明は、開放循環冷却水系の冷却水に塩素を添加してスライムを防止する方法において、冷却水系に補給される補給水に、補給水中の残留塩素が０ . ５〜２ mgCl ／Ｌになるように食塩水を電解して残留塩素を発生させた塩素水を添加するとともに、濃縮された冷却水を電解し、残留塩素を発生させることを特徴とする冷却水系のスライム防止方法を提供するものである。
【０００５】
【発明の実施の形態】
本発明の冷却水系のスライム防止方法においては、開放循環冷却水系の冷却水に塩素を添加してスライムを防止する方法において、冷却水系に補給される補給水に食塩水を電解して残留塩素を発生させた塩素水を添加するとともに、濃縮された冷却水を電解し、残留塩素を発生させる。本発明方法は、補給水中の塩化物イオン濃度が低く、冷却水系において塩化物イオンを濃縮させても、スライム処理に十分な残留塩素を発生することができない冷却水系に好適に適用することができる。
本発明方法において、補給水に添加する食塩水を電解して残留塩素を発生させた塩素水の製造方法に特に制限はなく、例えば、食塩水電解次亜塩素酸発生装置を用いて製造することができる。食塩水電解次亜塩素酸発生装置を用いて、無隔膜式電解槽で食塩水を電解すると、陽極と陰極で次のような反応が起こって塩素と水酸化ナトリウムが生成し、さらに塩素と水酸化ナトリウムが反応して次亜塩素酸ナトリウムが生成する。市販の食塩水電解次亜塩素酸発生装置を用いて、残留塩素濃度６０〜８０mgCl／Ｌ程度の塩素水を製造することができる。
２Ｃｌ- → Ｃｌ2 ＋ ２ｅ-
２Ｎａ+ ＋ ２Ｈ2Ｏ ＋ ２ｅ- → ２ＮａＯＨ ＋ Ｈ2
Ｃｌ2 ＋ ２ＮａＯＨ → ＮａＯＣｌ ＋ ＮａＣｌ ＋ Ｈ2Ｏ
本発明方法において、補給水への塩素水の添加量に特に制限はないが、補給水中の残留塩素濃度が０.１〜３mgCl／Ｌとなるように添加することが好ましく、０.５〜２mgCl／Ｌとなるように添加することがより好ましい。補給水中の残留塩素濃度が０.１mgCl／Ｌ未満であると、スライム防止効果が不十分となるおそれがある。補給水中の残留塩素濃度が３mgCl／Ｌを超えると、冷却水系の金属部材の腐食が速くなるおそれがある。
食塩水を電解して残留塩素を発生させた塩素水には、通常は残留塩素濃度の１０倍程度の塩化物イオンが含まれているので、補給水中の残留塩素濃度が０.１〜３mgCl／Ｌであると、補給水中に含まれる１〜３０mgCl-／Ｌ程度の塩化物イオンが冷却水系に送り込まれ、冷却水の濃縮とともに濃縮され、例えば、濃縮倍率１０倍で冷却水系を運転すると、濃縮された冷却水中の塩化物イオン濃度は１０〜３００mgCl-／Ｌ程度となる。
【０００６】
本発明方法において、濃縮された冷却水の電解方法に特に制限はなく、例えば、電極を冷却水のピットに浸漬して電解することができ、あるいは、冷却水系の配管に電解槽を設置して電解することもできる。電解槽の設置場所に特に制限はなく、例えば、冷却水の送り配管にバイパス配管を設けて電解槽を設置し、電解により残留塩素を発生させた冷却水をピットに返送することができ、冷却水の送り配管に電解槽を設置することもでき、あるいは、冷却水の戻り配管に電解槽を設置することもできる。
本発明方法に用いる電極の材質に特に制限はないが、陽極としては、例えば、チタンなどの耐食性の材料に、白金、イリジウムなどの白金系元素の単体又はその酸化物を被覆した残留塩素の発生効率が良好な材質を好適に用いることができる。陰極としては、例えば、ステンレス鋼、アルミニウム、銀などを用いることができるが、陰極と陽極を同一の材質とすることもできる。また、電流の方向を固定する必要はなく、電流の正負を定期的又は随意的に逆転させ、陰極と陽極とを反転させながら電解を行うことができる。電極の反転により、陰極に付着した炭酸カルシウムなどのスケールを剥離しながら運転することができるので、電解効率の低下を防ぐことができる。なお、この場合、両電極を同一の材質とすれば、一定の残留塩素の発生効率が得られる。この場合、用いる電極としては、例えば、チタンなどを基材とし、白金やイリジウムなどを被覆した電極などを挙げることができる。
【０００７】
本発明方法において、電解のために印加する直流電圧に特に制限はないが、２〜４０Ｖであることが好ましく、４〜３０Ｖであることがより好ましい。印加する電圧が２Ｖ未満であると、残留塩素の発生効率が低下するおそれがある。印加する電圧が４０Ｖを超えると、人体に対して危険性が生ずるおそれがある。本発明方法において、電解のために通電する電流に特に制限はないが、冷却水系の循環水量１ｍ3／ｈに対して、０.１〜３Ａであることが好ましい。電流が循環水量１ｍ3／ｈに対して０.１Ａ未満であると、残留塩素の発生量が過少となって、スライム防止効果が不十分となるおそれがある。電流が循環水量１ｍ3／ｈに対して３Ａを超えると、残留塩素濃度が高くなりすぎて金属の腐食を招くおそれがある。
図１は、本発明の冷却水系のスライム防止方法の実施の一態様の工程系統図である。補給水に食塩水電解残留塩素発生装置（図示していない。）において残留塩素を発生させた塩素水が添加され、冷却塔１のピット２に供給される。冷却水はピットから循環ポンプ３により送り出され、送り配管４、熱交換器５、戻り配管６を経由して冷却塔に返送される。送り配管にはバイパス配管７が接続され、バイパス配管へ流入した冷却水は、電解槽８で電解されて残留塩素が発生し、ピットに返送される。
本発明のスライム防止方法によれば、冷却水系において、抗菌剤などを使用することなく、金属部材の腐食を抑えて、しかもスライムの発生を効果的に防止することができる
【０００８】
【実施例】
以下に、実施例を挙げて本発明をさらに詳細に説明するが、本発明はこれらの実施例によりなんら限定されるものではない。
実施例１
図１に示す循環水量１００ｍ3／ｈの冷却水系において、試験を行った。
塩化物イオン濃度１.０mgCl-／Ｌの水に、食塩水電解次亜塩素酸発生装置により発生させた次亜塩素酸を含有する塩素水を、残留塩素濃度１.０mgCl／Ｌとなるように添加して補給水とした。補給水中の塩化物イオン濃度は、１１mgCl-／Ｌであった。
腐食性試験の試験片として、材質が低炭素鋼のＪＩＳ Ｇ ３１４１の１種（ＳＰＣＣ）であり、ＪＩＳ Ｋ ０１００の付図４に記載された円形試験片を冷却水ピットに浸漬した。
濃縮された冷却水中の塩化物イオン濃度を１１０mgCl-／Ｌとして、冷却水系を濃縮倍数が１０倍となるように運転し、さらに循環水を電解槽に通水して次亜塩素酸を発生させ、残留塩素濃度を０.５mgCl／Ｌに維持しつつ３０日間の運転を行った。
３０日後の冷却水中の一般細菌数は１０2ＣＦＵ（colony forming unit）／mLであり、低炭素鋼試験片の腐食速度は１０ｍｄｄ（mg／dm2／day）であった。
比較例１
循環水を電解槽に通水して次亜塩素酸を発生させる操作を行わなかった以外は、実施例１と同様にして、冷却水系の運転を３０日間行った。濃縮された冷却水中の塩化物イオン濃度は１１０mgCl-／Ｌであり、残留塩素濃度は０.１mgCl／Ｌであった。
３０日後の冷却水中の一般細菌数は１０5ＣＦＵ／mLであり、低炭素鋼試験片の腐食速度は１５ｍｄｄであった。
比較例２
実施例１と同じ冷却水系において、塩化物イオン濃度１.０mgCl-／Ｌの水に、食塩水電解次亜塩素酸発生装置から発生させた次亜塩素酸を含有する塩素水を、残留塩素濃度５.０mgCl／Ｌとなるように添加して補給水とした。補給水中の塩化物イオン濃度は、５１mgCl-／Ｌであった。冷却水ピットには、実施例１と同じ低炭素鋼試験片を浸漬した。
循環水を電解槽に通水して次亜塩素酸を発生させる操作を行うことなく、冷却水系を濃縮倍数１０倍となるようにして３０日間運転した。濃縮された冷却水中の塩化物イオン濃度は５１０mgCl-／Ｌであり、残留塩素濃度は０.５mgCl／Ｌであった。
３０日後の冷却水中の一般細菌数は１０2ＣＦＵ／mLであり、低炭素鋼試験片の腐食速度は４０ｍｄｄであった。
実施例１及び比較例１〜２の結果を、第１表に示す。
【０００９】
【表１】
第１表に見られるように、補給水に食塩水電解次亜塩素酸発生装置により発生させた次亜塩素酸を含有する塩素水を添加し、さらに循環水を電解槽に通水して次亜塩素酸を発生させた実施例１においては、冷却水中の一般細菌数が少なく、スライム防止効果が十分に発現することが予測され、また、低炭素鋼試験片の腐食速度も小さい。
これに対して、循環水を電解槽に通水して次亜塩素酸を発生させる操作を行わなかった比較例では、補給水中の塩化物イオン濃度を実施例１と同じにすると、循環水中の残留塩素濃度が低くなり、低炭素鋼試験片の腐食速度は大きくないが、一般細菌数が多く、スライムの発生が予測される。一方、補給水中の塩化物イオン濃度を高くして、循環水中の残留塩素濃度を実施例１と同じにすると、冷却水中の一般細菌数は少なくなるが、低炭素鋼試験片の腐食速度が大きく、冷却水系における金属部材の腐食の進行が速いことが予測される。
【００１１】
【発明の効果】
本発明のスライム防止方法によれば、冷却水系において、抗菌剤などを使用することなく、金属部材の腐食を抑えて、しかもスライムの発生を効果的に防止することができる
【図面の簡単な説明】
【図１】図１は、本発明方法の実施の一態様の工程系統図である。
【符号の説明】
１ 冷却塔
２ ピット
３ 循環ポンプ
４ 送り配管
５ 熱交換器
６ 戻り配管
７ バイパス配管
８ 電解槽[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cooling water-based slime prevention method. More specifically, the present invention relates to a cooling water system slime prevention method capable of suppressing corrosion of a metal member and effectively preventing slime generation in a cooling water system.
[0002]
[Prior art]
Cooling water is used in large quantities in various industrial fields such as the petrochemical industry and the steel industry for the purpose of indirectly or directly cooling workpieces, or for air conditioning, heating and cooling of buildings, and related equipment. ing. In recent years, from the viewpoint of lack of water resources and effective use, advanced use of cooling water has been carried out in order to reduce the amount of cooling water used, such as reducing the amount of forced blow in highly concentrated operation of open circulation cooling water systems. Yes. In this way, when cooling water is used at a high level, the quality of circulating cooling water deteriorates due to the concentration of dissolved salts and nutrients, etc., and soil, sand, dust, etc. are mixed with microorganisms such as bacteria, sputum and algae. The slime formed is likely to be generated, causing a decrease in thermal efficiency and water flow in the heat exchanger, and inducing local corrosion of equipment and piping at the lower part of the slime adhesion.
Therefore, various antibacterial agents, for example, oxidizing antibacterial agents such as sodium hypochlorite and hydrogen peroxide water, are used to prevent such slime damage. These antibacterial agents are stored in a medicine tank and injected into a cooling water system by a chemical injection pump. However, if antibacterial agent is used to prevent slime, it requires labor for transportation such as lorry transportation, container movement, etc., and there is a risk of causing leakage during handling of the antibacterial agent and causing damage to the human body. There is a problem that it takes time to check the remaining amount and periodically replenish it.
An electrolytic hypochlorous acid generator is used in order to prevent slime trouble which is a problem in the cooling water system. However, when the chloride ion concentration in the make-up water is low, even if the chloride ion is concentrated in the cooling water system, the generation rate of hypochlorous acid sufficient for slime treatment cannot be obtained. In addition, when the salt ion or the like is added to the cooling water to increase the chloride ion concentration, there is a problem that the metal member in contact with the cooling water is easily corroded. For this reason, there has been a demand for a cooling water-based slime prevention method capable of suppressing corrosion of metal members and effectively preventing slime generation.
[0003]
[Problems to be solved by the invention]
An object of the present invention is to provide a cooling water-based slime prevention method capable of suppressing corrosion of metal members and effectively preventing slime generation in an open circulating cooling water system.
[0004]
[Means for Solving the Problems]
As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention added chlorine water that has electrolyzed salt water and generated residual chlorine to makeup water in an open circulating cooling water system, and further added to the circulating water system. It has been found that by installing an electrolytic cell to generate residual chlorine, the corrosion rate of the metal member is small, and the generation rate of residual chlorine necessary and sufficient for slime prevention can be obtained. It came to be completed.
That is, according to the present invention, in the method for preventing slime by adding chlorine to the cooling water in the open circulation cooling water system, residual chlorine in the makeup water is 0.5 to 2
[0005]
DETAILED DESCRIPTION OF THE INVENTION
In the cooling water system slime prevention method of the present invention, chlorine is added to the cooling water in the open circulation cooling water system to prevent slime. While adding the generated chlorine water, the concentrated cooling water is electrolyzed to generate residual chlorine. The method of the present invention can be suitably applied to a cooling water system that has a low chloride ion concentration in the makeup water and cannot generate sufficient residual chlorine for slime treatment even if the chloride ion is concentrated in the cooling water system. .
In the method of the present invention, there is no particular limitation on the production method of chlorinated water in which residual chlorine is generated by electrolyzing the saline solution added to the makeup water. For example, it is produced using a saline electrolyzed hypochlorous acid generator. Can do. When electrolyzing saline in a diaphragm-type electrolytic cell using a saline electrolytic hypochlorous acid generator, the following reaction occurs at the anode and cathode to produce chlorine and sodium hydroxide, and further, chlorine and water. Sodium oxide reacts to produce sodium hypochlorite. Chlorine water having a residual chlorine concentration of about 60 to 80 mgCl / L can be produced using a commercially available saline electrolysis hypochlorous acid generator.
2Cl − → Cl 2 + 2e −
2Na + + 2H 2 O + 2e − → 2NaOH + H 2
Cl 2 + 2NaOH → NaOCl + NaCl + H 2 O
In the method of the present invention, the amount of chlorine water added to the makeup water is not particularly limited, but it is preferably added so that the residual chlorine concentration in the makeup water is 0.1 to 3 mgCl / L, and 0.5 to 2 mgClCl. It is more preferable to add so as to be / L. If the residual chlorine concentration in the make-up water is less than 0.1 mg Cl / L, the slime prevention effect may be insufficient. If the residual chlorine concentration in the makeup water exceeds 3 mgCl / L, the cooling water metal member may be corroded faster.
Chlorine water generated by electrolyzing salt water to generate residual chlorine usually contains about 10 times the chloride concentration of the residual chlorine, so the residual chlorine concentration in the makeup water is 0.1 to 3 mgCl / When it is L, about 1 to 30 mg Cl − / L of chloride ions contained in the makeup water is sent to the cooling water system and concentrated together with the concentration of the cooling water. For example, when the cooling water system is operated at a concentration ratio of 10 times, The concentration of chloride ions in the cooled water is about 10 to 300 mg Cl − / L.
[0006]
In the method of the present invention, the method for electrolyzing the concentrated cooling water is not particularly limited. For example, the electrode can be immersed in the pit of the cooling water for electrolysis, or an electrolytic cell is installed in the cooling water system pipe. It can also be electrolyzed. There are no particular restrictions on the location of the electrolytic cell. For example, a bypass pipe can be installed in the cooling water feed pipe to install the electrolytic tank, and the cooling water that has generated residual chlorine by electrolysis can be returned to the pit. An electrolytic cell can be installed in the water feed pipe, or an electrolytic cell can be installed in the cooling water return pipe.
The material of the electrode used in the method of the present invention is not particularly limited, but as the anode, for example, generation of residual chlorine in which a corrosion-resistant material such as titanium is coated with a single element of platinum-based element such as platinum or iridium or an oxide thereof. A material having good efficiency can be preferably used. As the cathode, for example, stainless steel, aluminum, silver or the like can be used, but the cathode and the anode can be made of the same material. Further, it is not necessary to fix the direction of the current, and the electrolysis can be performed while reversing the polarity of the current periodically or arbitrarily and reversing the cathode and the anode. By reversing the electrodes, it is possible to operate while peeling the scale such as calcium carbonate attached to the cathode, so that it is possible to prevent a reduction in electrolytic efficiency. In this case, if both electrodes are made of the same material, a certain residual chlorine generation efficiency can be obtained. In this case, as an electrode to be used, for example, an electrode in which titanium or the like is used as a base material and platinum or iridium is coated can be used.
[0007]
In the method of the present invention, there is no particular limitation on the DC voltage applied for electrolysis, but it is preferably 2 to 40V, more preferably 4 to 30V. If the voltage to be applied is less than 2 V, the generation efficiency of residual chlorine may be reduced. If the applied voltage exceeds 40V, there is a risk of danger to the human body. In the method of the present invention, the current to be energized for electrolysis is not particularly limited, but is preferably 0.1 to 3 A with respect to the circulating water amount 1 m 3 / h in the cooling water system. If the current is less than 0.1 A with respect to the circulating water volume of 1 m 3 / h, the amount of residual chlorine generated becomes too small and the slime prevention effect may be insufficient. If the current exceeds 3 A with respect to the circulating water volume of 1 m 3 / h, the residual chlorine concentration becomes too high, which may cause metal corrosion.
FIG. 1 is a process flow diagram of one embodiment of the cooling water system slime prevention method of the present invention. Chlorine water in which residual chlorine is generated in a brine electrolysis residual chlorine generator (not shown) is added to the makeup water and supplied to the
According to the slime prevention method of the present invention, corrosion of a metal member can be suppressed and the generation of slime can be effectively prevented without using an antibacterial agent or the like in the cooling water system.
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.
Example 1
The test was performed in a cooling water system having a circulating water amount of 100 m 3 / h shown in FIG.
Chloride ion concentration 1.0mgCl - / water of L, and chlorine water containing hypochlorous acid generated by a saline electrolysis hypochlorite generator, so that the residual chlorine concentration 1.0mgCl / L Added to make up makeup water. Chloride ion concentration of the supply water, 11mgCl - / was L.
As a test piece for the corrosive test, the material is one of low carbon steel JIS G 3141 (SPCC), and the circular test piece described in FIG. 4 of JIS K 0100 was immersed in a cooling water pit.
Concentrated chloride ion concentration in the cooling water 110MgCl - as / L, concentration multiples cooling water system is operated so as to be 10 times, and further the circulating water was passed through the electrolytic cell to generate hypochlorous acid The operation was performed for 30 days while maintaining the residual chlorine concentration at 0.5 mgCl / L.
After 30 days, the number of general bacteria in the cooling water was 10 2 CFU (colony forming unit) / mL, and the corrosion rate of the low carbon steel specimen was 10 mdd (mg / dm 2 / day).
Comparative Example 1
The cooling water system was operated for 30 days in the same manner as in Example 1 except that the operation of passing circulating water through the electrolytic cell and generating hypochlorous acid was not performed. Chloride ion concentration of the concentrated cooling water 110mgCl - / L, and the residual chlorine concentration was 0.1mgCl / L.
The number of general bacteria in the cooling water after 30 days was 10 5 CFU / mL, and the corrosion rate of the low carbon steel specimen was 15 mdd.
Comparative Example 2
In the same cooling water system as in Example 1, chlorine water containing hypochlorous acid generated from a saline electrolytic hypochlorous acid generator was added to water having a chloride ion concentration of 1.0 mg Cl − / L, and the residual chlorine concentration was It was added so as to be 5.0 mgCl / L and used as make-up water. Chloride ion concentration of the supply water, 51mgCl - / was L. The same low carbon steel specimen as in Example 1 was immersed in the cooling water pit.
The cooling water system was operated for 30 days with the concentration factor being 10 times without performing the operation of passing circulating water through the electrolytic cell to generate hypochlorous acid. Chloride ion concentration of the concentrated cooling water 510mgCl - / L, and the residual chlorine concentration was 0.5mgCl / L.
The number of general bacteria in the cooling water after 30 days was 10 2 CFU / mL, and the corrosion rate of the low-carbon steel specimen was 40 mdd.
The results of Example 1 and Comparative Examples 1 and 2 are shown in Table 1.
[0009]
[Table 1]
As can be seen in Table 1, chlorine water containing hypochlorous acid generated by a saline electrolytic hypochlorous acid generator was added to the makeup water, and the circulating water was passed through the electrolytic cell. In Example 1 in which chlorous acid was generated, the number of general bacteria in the cooling water was small, and it was predicted that the slime prevention effect was sufficiently exhibited, and the corrosion rate of the low-carbon steel specimen was low.
On the other hand, in the comparative example in which circulating water was passed through the electrolytic cell and the operation of generating hypochlorous acid was not performed, if the chloride ion concentration in the makeup water was the same as in Example 1, Although the residual chlorine concentration is low and the corrosion rate of the low-carbon steel specimen is not large, the number of general bacteria is large and the occurrence of slime is predicted. On the other hand, if the chloride ion concentration in the make-up water is increased and the residual chlorine concentration in the circulating water is the same as in Example 1, the number of general bacteria in the cooling water decreases, but the corrosion rate of the low-carbon steel specimen increases. It is predicted that the corrosion of the metal member in the cooling water system is fast.
[0011]
【The invention's effect】
According to the slime prevention method of the present invention, corrosion of a metal member can be suppressed and the generation of slime can be effectively prevented without using an antibacterial agent or the like in the cooling water system. ]
FIG. 1 is a process flow diagram of one embodiment of the method of the present invention.
[Explanation of symbols]
1 Cooling
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001046409A JP4013486B2 (en) | 2001-02-22 | 2001-02-22 | Cooling water slime prevention method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001046409A JP4013486B2 (en) | 2001-02-22 | 2001-02-22 | Cooling water slime prevention method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2002248478A JP2002248478A (en) | 2002-09-03 |
| JP4013486B2 true JP4013486B2 (en) | 2007-11-28 |
Family
ID=18908041
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2001046409A Expired - Fee Related JP4013486B2 (en) | 2001-02-22 | 2001-02-22 | Cooling water slime prevention method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4013486B2 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4117607B2 (en) * | 2002-10-01 | 2008-07-16 | 栗田工業株式会社 | Cooling water treatment method |
| JP4703246B2 (en) * | 2005-04-21 | 2011-06-15 | 三洋電機株式会社 | Refrigeration equipment |
| JP4688613B2 (en) * | 2005-08-30 | 2011-05-25 | 三洋電機株式会社 | Air conditioner |
| JP2007205591A (en) * | 2006-01-31 | 2007-08-16 | Miura Co Ltd | Operating method of cooling tower |
| JP2012115720A (en) * | 2010-11-29 | 2012-06-21 | Hakuto Co Ltd | Biocidal method of circulating water system in open type water cooling tower |
-
2001
- 2001-02-22 JP JP2001046409A patent/JP4013486B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP2002248478A (en) | 2002-09-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4116949B2 (en) | Electrochemical sterilization and sterilization method | |
| CN104903251B (en) | Electrolyzed water production method and generator | |
| JP3716042B2 (en) | Acid water production method and electrolytic cell | |
| JP3428998B2 (en) | Electrolyzer producing mixed oxidant gas | |
| US20180346352A1 (en) | Electrochemicl system and method for on-site generation of oxidants at high current density | |
| US4345981A (en) | Anodically polarized surface for biofouling and scale control | |
| KR100883894B1 (en) | Apparatus for producing non-acidic hypochlorous acid and method for producing non-acidic hypochlorite | |
| JP2006098003A (en) | Circulating cooling water system electrolytic treatment method and electrolytic treatment apparatus | |
| US5039383A (en) | Halogen generation | |
| JP4117607B2 (en) | Cooling water treatment method | |
| EP0826794A1 (en) | Apparatus for producing hypochlorite | |
| JP2010194402A (en) | Water treatment system and treatment method of cooling system circulating water | |
| JP3520060B2 (en) | Hypochlorous acid generation method and apparatus | |
| JPS6039757B2 (en) | Hydrochloric acid electrolysis method | |
| JP4013486B2 (en) | Cooling water slime prevention method | |
| JP6300252B1 (en) | Water treatment system, electrode corrosion inhibiting method and electrode corrosion inhibiting device for water treatment system | |
| JP3685384B2 (en) | Slime prevention method | |
| JP2627101B2 (en) | Additive chemicals for the production of electrolytic hypochlorous acid sterilized water | |
| JP2006255653A (en) | Water-based electrolytic treatment method | |
| JP2006095426A (en) | Circulating cooling water system electrolytic treatment method and electrolytic treatment apparatus | |
| JP3422366B2 (en) | Cooling water slime prevention method | |
| JP4925079B2 (en) | Water treatment method and water treatment apparatus | |
| JP3521896B2 (en) | Water treatment method for cooling water system | |
| JP3928455B2 (en) | Water treatment method for cooling water system | |
| JP2002239557A (en) | Slime prevention method for cooling water system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20040604 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20050815 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20070416 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20070615 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20070821 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20070903 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100921 Year of fee payment: 3 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110921 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120921 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130921 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140921 Year of fee payment: 7 |
|
| LAPS | Cancellation because of no payment of annual fees |