JP2625132B2 - Chemical cleaning method for poorly soluble scale - Google Patents
Chemical cleaning method for poorly soluble scaleInfo
- Publication number
- JP2625132B2 JP2625132B2 JP62316052A JP31605287A JP2625132B2 JP 2625132 B2 JP2625132 B2 JP 2625132B2 JP 62316052 A JP62316052 A JP 62316052A JP 31605287 A JP31605287 A JP 31605287A JP 2625132 B2 JP2625132 B2 JP 2625132B2
- Authority
- JP
- Japan
- Prior art keywords
- scale
- poorly soluble
- cleaning method
- chemical cleaning
- cleaning
- 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 - Lifetime
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING 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
- C23F—NON-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
- C23F11/00—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
- C23F11/08—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
- C23F11/10—Inhibiting 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 organic inhibitors
-
- C—CHEMISTRY; METALLURGY
- C23—COATING 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
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/14—Cleaning or pickling metallic material with solutions or molten salts with alkaline solutions
- C23G1/19—Iron or steel
-
- C—CHEMISTRY; METALLURGY
- C23—COATING 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
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/24—Cleaning or pickling metallic material with solutions or molten salts with neutral solutions
- C23G1/26—Cleaning or pickling metallic material with solutions or molten salts with neutral solutions using inhibitors
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
- F22B37/00—Component parts or details of steam boilers
- F22B37/02—Component parts or details of steam boilers applicable to more than one kind or type of steam boiler
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、鉄系金属面に生成付着する難溶性スケール
を溶解除去するための化学的洗浄方法に関する。Description: TECHNICAL FIELD The present invention relates to a chemical cleaning method for dissolving and removing a hardly soluble scale formed and attached to an iron-based metal surface.
鉄系金属表面例えば、火力発電所等のボイラ過熱器管
や主蒸気管内面に生成付着する水蒸気酸化スケールは、
運転時間の経過と共にスケール厚が増大し、ある厚さに
達すると剥離する現象が見られている。特にこの水蒸気
酸化スケールの剥離脱落が一時期に集中的に起るとボイ
ラ過熱器管の閉塞やタービンノズル，タービンブレード
および弁類の摩耗等の障害が発生するため、その前にス
ケールを除去する必要がある。これら、過熱器管や主蒸
気管内面の水蒸気酸化スケール構造は大別すると外層と
内層の二層から成り、外層スケールは主として硬質，緻
密な、ほぼ純粋に近いマグネタイト（Fe3O4）である
が、金属層に面した内層スケールはCrを主体としたスピ
ネル型酸化物（材質がオーステナイト系ステンレス鋼の
場合）あるいはCr,MoおよびSi等を含むスピネル型酸化
物（材質がフェライト系Cr-Mo鋼の場合）である。For example, steam oxidation scale formed and adhered to the inner surface of boiler superheater tubes and main steam pipes of iron-based metal surfaces, such as thermal power plants,
It has been observed that the scale thickness increases as the operation time elapses and peels off when the thickness reaches a certain thickness. In particular, if the steam oxidation scale peels and falls intensively at one time, it will cause obstacles such as clogging of the boiler superheater tubes and wear of turbine nozzles, turbine blades and valves, so it is necessary to remove the scale before that. There is. These steam oxidation scale structures on the inner surface of the superheater tube and main steam tube are roughly divided into two layers, an outer layer and an inner layer. The outer layer scale is mainly hard, dense, and almost pure magnetite (Fe 3 O 4 ). However, the inner layer scale facing the metal layer is a spinel-type oxide mainly composed of Cr (when the material is austenitic stainless steel) or a spinel-type oxide containing Cr, Mo, Si, etc. (the material is ferrite-based Cr-Mo In the case of steel).
これら難溶性の金属酸化物やスピネル型の金属酸化物
を含む水蒸気酸化スケールは結晶構造が緻密なために化
学的に安定性が高く、特にボイラの過熱器管や主蒸気管
内面の水蒸気酸化スケールは全体が難溶性スケールから
成っているため、溶解除去は極めて困難とされており、
従来はスケールによるトラブルがあっても国内では化学
洗浄によって、これらのスケールを溶解除去した実績は
なく、スケールによって閉塞した管を切断し、取替えた
り、摩耗したタービンノズルおよびタービンブレードを
取替えたりしている。The steam oxidation scale containing these hardly soluble metal oxides and spinel-type metal oxides has high chemical stability due to the dense crystal structure, especially the steam oxidation scale on the inner surface of the boiler superheater tube or main steam tube. Is made of a poorly soluble scale, so it is extremely difficult to dissolve and remove it.
In the past, there was no record of dissolving and removing these scales by chemical cleaning in Japan, even if there was a problem with scales.Therefore, pipes clogged by scales were cut and replaced, and worn turbine nozzles and turbine blades were replaced. I have.
また、ボイラ蒸発管のような伝熱面に付着しているス
ケールの溶解除去については、一般にクエン酸アンモニ
ウム溶液またはポリアミノカルボン酸アンモニウム塩溶
液等が用いられている。Further, for dissolving and removing scales attached to a heat transfer surface such as a boiler evaporator tube, an ammonium citrate solution or a polyaminocarboxylic acid ammonium salt solution is generally used.
上述のように、従来はスケールによって閉塞した管を
切断して取替えたり、摩耗したタービンノズルおよびタ
ービンブレードを取替えたりしているがそれに要する費
用およびボイラ停止による発電損失が莫大であるという
問題点があった。As described above, conventionally, pipes clogged by scale have been cut and replaced, or worn turbine nozzles and turbine blades have been replaced.However, there has been a problem that the cost required and power generation loss due to boiler shutdown are enormous. there were.
また、クエン酸，アンモニウム溶液またはポリアミノ
カルボン酸アンモニウム塩溶液等の洗浄液による洗浄で
はボイラ過熱器管や主蒸気管内面の水蒸気酸化スケール
は殆ど溶解されないという問題点があった。Further, there is a problem that the steam oxidation scale on the inner surface of the boiler superheater tube or the main steam tube is hardly dissolved by cleaning with a cleaning solution such as a citric acid, ammonium solution or a polyaminocarboxylic acid ammonium salt solution.
本発明は、かゝる現状に鑑みなされたものでボイラ過
熱器管や主蒸気管内面の硬質スケールが飛散してタービ
ン入口ノズル，タービンブレードの摩耗を生じタービン
の効率低下および各種バルブの弁類の損傷を防止するた
め、難溶性の硬質スケールを完全に溶解除去し、これら
摩耗の根源をなくすことができる難溶性スケールの化学
的洗浄方法を提供することを目的とするものである。SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and hard scale on the inner surface of a boiler superheater tube or a main steam tube is scattered to cause wear of a turbine inlet nozzle and a turbine blade, resulting in a reduction in turbine efficiency and various valve valves. An object of the present invention is to provide a method for chemically cleaning a hardly soluble scale, which can completely dissolve and remove a hardly soluble hard scale in order to prevent the damage of the hardly soluble scale.
本発明はポリアミノカルボン酸にアンモニア水、アン
モニアガス、モルホリン、シクロヘキシルアミン、モノ
エタノールアミン、ジエタノールアミンおよびトリエタ
ノールアミンからなる郡の中から選ばれた少くとも１種
の化合物を添加してpHを6.5〜9.0に調整した洗浄液に水
化ヒドラジンを添加してpHを7.0〜9.5に調整した上更に
腐食抑制剤を添加して得られた混合液により、前処理工
程を含むことなく１工程で鉄系金属面に生成付着した難
溶性スケールを120℃〜160℃の温度範囲で20時間以上の
処理時間で溶解除去することを特徴とする難溶性スケー
ルの化学的洗浄方法を提案するものである。The present invention comprises adding at least one compound selected from the group consisting of ammonia water, ammonia gas, morpholine, cyclohexylamine, monoethanolamine, diethanolamine and triethanolamine to a polyaminocarboxylic acid to adjust the pH to 6.5 to 6.5. A hydrated hydrazine is added to the washing solution adjusted to 9.0 to adjust the pH to 7.0 to 9.5, and a mixed solution obtained by further adding a corrosion inhibitor is used. The present invention proposes a chemical cleaning method for a hardly soluble scale, wherein the hardly soluble scale formed and adhered to a surface is dissolved and removed in a temperature range of 120 ° C to 160 ° C for a processing time of 20 hours or more.
本発明の化学的洗浄方法は、従来の洗浄液では溶解除
去が全く不可能であった上記難溶性の水蒸気酸化スケー
ルを完全に溶解除去可能にしたことを特徴としている。The chemical cleaning method of the present invention is characterized by completely dissolving and removing the hardly soluble steam oxidation scale, which was completely impossible to dissolve and remove with a conventional cleaning liquid.
本発明の有効なポリアミノカルボン酸としては、エチ
レンジアミン４酢酸（以下EDTAという），ジエチレント
リアミン５酢酸（以下DTPAという），ニトロ３酢酸（以
下NTAという）およびヒドロキシエチルエチレンジアミ
ン４酢酸（以下HEDTAという）等がある。これらポリア
ミノカルボン酸の濃度はボイラ過熱器管や主蒸気管内面
に生成付着している水蒸気酸化スケールの量に応じて算
定されるが、水蒸気酸化スケールの剥離現象は蒸気温度
およびボイラの発停回数によっても異なるがボイラ運転
開始後７〜８年を要するので、その経過時間からのスケ
ール量から判断して10〜30重量％が必要である。Examples of useful polyaminocarboxylic acids of the present invention include ethylenediaminetetraacetic acid (hereinafter referred to as EDTA), diethylenetriaminepentaacetic acid (hereinafter referred to as DTPA), nitrotriacetic acid (hereinafter referred to as NTA), and hydroxyethylethylenediaminetetraacetic acid (hereinafter referred to as HEDTA). is there. The concentration of these polyaminocarboxylic acids is calculated according to the amount of steam oxidation scale formed and adhered to the inner surface of the boiler superheater tube or main steam tube. Although it depends on the boiler operation, it takes 7 to 8 years after the start of the boiler operation.
また、上記のポリアミノカルボン酸に、アンモニア
水，アンモニアガス，モルホリン，シクロヘキシルアミ
ン，モノエタノールアミン，ジエタノールアミンおよび
トリエタノールアミンなどのアミン系アルカリ剤を添加
し、pHを6.5〜9.0に調整することによりポリアミノカル
ボン酸を塩の形とし、スケールを構成する金属とのキレ
ートの形成が容易なキレート化剤とする。Further, an amine-based alkali agent such as aqueous ammonia, ammonia gas, morpholine, cyclohexylamine, monoethanolamine, diethanolamine, and triethanolamine is added to the above polyaminocarboxylic acid, and the pH is adjusted to 6.5 to 9.0 to adjust the polyaminocarboxylic acid. The carboxylic acid is in the form of a salt, and is a chelating agent that easily forms a chelate with a metal constituting the scale.
さらにまた本発明の洗浄液による機器の洗浄にあたっ
て腐食抑制剤を添加する必要があるが、腐食抑制剤とし
ては、それが金属面に吸着作用を発揮して腐食抑制効果
を十分奏するものならば、公知の腐食抑制剤を適宜選択
して使用し得る。例えば有機アミン系インヒビター（杉
村化学工業株式会社製、商品名「ヒビロンＫ−400」）
があげられる。その使用濃度は0.3重量％で十分であ
る。Furthermore, it is necessary to add a corrosion inhibitor when cleaning equipment with the cleaning liquid of the present invention. As the corrosion inhibitor, if it exhibits an adsorption effect on a metal surface and sufficiently exhibits a corrosion inhibitory effect, it is known. Can be appropriately selected and used. For example, organic amine-based inhibitors (trade name “Hibiron K-400” manufactured by Sugimura Chemical Industry Co., Ltd.)
Is raised. Its use concentration of 0.3% by weight is sufficient.
本発明による洗浄は上述に基づいて調整した洗浄液を
難溶性スケールが生成付着している被処理機器、例え
ば、ボイラの過熱器管および主蒸気管内に注入し、洗浄
液を循環しながら120〜160℃の温度において20時間以上
の処理時間をかけて難溶性スケールを溶解除去する。In the cleaning according to the present invention, the cleaning liquid adjusted on the basis of the above is injected into a processing target device having a hardly soluble scale formed and adhered thereto, for example, a superheater pipe and a main steam pipe of a boiler, and the cleaning liquid is circulated at 120 to 160 ° C. At a temperature of, a treatment time of at least 20 hours is used to dissolve and remove the poorly soluble scale.
なお、洗浄液のpHが７に近ずく程、洗浄温度は120℃
程度まで低くしても良くそれ以下の温度では難溶性スケ
ールの溶解性が悪くなる。As the pH of the washing solution approaches 7, the washing temperature becomes 120 ° C.
The temperature may be lowered to a lower level, but at a temperature lower than that, the solubility of the poorly soluble scale becomes poor.
一方pHが9.5に近ずく程、洗浄温度は160℃程度まで高
くしないと難溶性スケールは十分溶解しなくなり、pH9.
5以上になると洗浄温度を高くしてもスケールの溶解性
は著しく低下する。On the other hand, as the pH approaches 9.5, the sparingly soluble scale will not sufficiently dissolve unless the washing temperature is raised to about 160 ° C.
If it is 5 or more, the solubility of the scale is significantly reduced even if the washing temperature is increased.
本発明の洗浄液によるスケール溶解機構は明確ではな
いが、水化ヒドラジンを併用添加してpH調整することに
より、スケール溶解力が顕著に促進されることから、ポ
リアミノカルボン酸塩のキレート化作用によってスケー
ルが溶出したFeY-（ポリアミノカルボン酸第二鉄）をヒ
ドラジンが逐次還元してFeY2-（ポリアミノカルボン酸
第一鉄）となるため、スケール表面は常時還元域とな
り、ポリアミノカルボン酸塩によるスケール溶解が促進
側に強く働くためと推測される。Although the mechanism of scale dissolution by the washing solution of the present invention is not clear, the scale dissolving power is remarkably promoted by adjusting the pH by adding hydrazine hydrate in combination, and the scale is dissolved by the chelating action of the polyaminocarboxylate. There eluted FEY - for the (poly amino acid ferric) hydrazine is sequentially reduced FEY 2-(ferrous polyamino acids), the scale surface becomes constantly reducing zone, scale dissolution by poly aminocarboxylate Is presumed to work strongly on the promotion side.
第１表〜第３表に示した洗浄液500mlをオートクレー
ブ（容量１、圧力200Kc/cm2、撹拌可能な加熱圧力容
器）にとり、これに実機の主蒸気管内面に生成付着した
水蒸気酸化スケール（スケール厚み：約0.5mm）7.0g
（完全に溶解するとFeで10,000ppmとなる）を加え、常
時撹拌しながら第１表〜第３表に示す温度および時間で
溶解試験した後、水蒸気酸化スケールの溶解量（asFe）
を測定した。その結果を第１表〜第３表に示す。500 ml of the cleaning liquid shown in Tables 1 to 3 was placed in an autoclave (capacity 1, pressure 200 Kc / cm 2 , a stirable heating pressure vessel), and steam oxidation scale (scale) formed and adhered to the inner surface of the main steam pipe of the actual machine Thickness: about 0.5mm) 7.0g
(When completely dissolved, it becomes 10,000 ppm of Fe), and after performing a dissolution test at the temperature and time shown in Tables 1 to 3 with constant stirring, the dissolved amount of steam oxidation scale (asFe)
Was measured. The results are shown in Tables 1 to 3.
また、従来洗浄液についても同様の試験を行って比較
した。その結果を第１表〜第３表に示す。In addition, the same test was performed for a conventional cleaning liquid and compared. The results are shown in Tables 1 to 3.
第１表〜第３表から判るように、本発明の洗浄液は比
較例の洗浄液に比べて水蒸気酸化スケールの溶解率はほ
とんどが80〜99.8％と非常にすぐれている。As can be seen from Tables 1 to 3, the cleaning liquid of the present invention has a very high solubility of 80 to 99.8% of the steam oxidation scale as compared with the cleaning liquid of the comparative example.
一方、比較例1,5,10,14,17,22,25,28,32,36はポリア
ミノカルボン酸を非還元性のアミン系アルカリ剤のみで
pH調整したものであるが、水化ヒドラジンを併用添加し
ないと水 蒸気酸化スケールの溶解率はほとんどが10％以下と非常
に低く実用できない。On the other hand, Comparative Examples 1,5,10,14,17,22,25,28,32,36 prepared polyaminocarboxylic acids using only non-reducing amine-based alkali agents.
pH adjusted, but water cannot be added unless hydrazine hydrate is added together. The dissolution rate of steam oxidation scale is very low at 10% or less, making it impractical.
またクエン酸アンモニウム溶液を用いた比較例40,41
の場合は水蒸気酸化スケールの溶解率は非常に低く殆ど
溶解しないことが明らかである。Comparative Examples 40 and 41 using ammonium citrate solution
In the case of, it is clear that the dissolution rate of the steam oxidation scale is very low and hardly dissolves.
本発明の方法によれば次のような効果を奏する。 According to the method of the present invention, the following effects can be obtained.
（１）従来の洗浄液では溶解除去が不可能であった硬質
緻密な難溶性の水蒸気酸化スケールに対しても溶解力が
著しく向上し、溶解除去が可能となった。(1) The dissolving power is remarkably improved even for a hard, dense, hardly soluble steam oxidation scale, which cannot be dissolved and removed by the conventional cleaning liquid, and can be dissolved and removed.
（２）洗浄時に溶出する有害な酸化第二鉄イオン（F
e3+）を無害な第一鉄イオン（Fe2+）に還元する作用を
有するため、洗浄面の鋼材の腐食を有効に抑制できる。(2) Harmful ferric oxide ions (F
e 3+ ) is reduced to harmless ferrous ions (Fe 2+ ), so that corrosion of the steel material on the cleaning surface can be effectively suppressed.
（３）従来不可能であったボイラ過熱器や主蒸気管内面
の難溶性の水蒸気酸化スケールを完全に溶解除去するこ
とが可能となったので、スケールの剥離脱落前に定期的
（７〜８年毎）に洗浄することにより、タービンへの障
害をなくすることができる。(3) Since it becomes possible to completely dissolve and remove the hardly soluble steam oxidation scale on the inner surface of the boiler superheater or the main steam pipe, which was impossible in the past, it is necessary to periodically dissolve (7-8) By cleaning every year), the trouble to the turbine can be eliminated.
フロントページの続き (72)発明者 石田 光彦 長崎県長崎市飽の浦町１番１号 三菱重 工業株式会社長崎造船所内 (72)発明者 新村 昭洋 長崎県長崎市飽の浦町１番１号 三菱重 工業株式会社長崎造船所内 (56)参考文献 特公 昭52−21456（ＪＰ，Ｂ２) 特公 昭53−20252（ＪＰ，Ｂ２)Continued on the front page (72) Inventor Mitsuhiko Ishida 1-1, Akunoura-cho, Nagasaki-shi, Nagasaki Mitsubishi Heavy Industries, Ltd. Nagasaki Shipyard (72) Inventor Akihiro Niimura 1-1, Akunoura-cho, Nagasaki-shi, Nagasaki Mitsubishi Heavy Industries, Ltd. (56) References: JP 52-21456 (JP, B2) JP 53-20252 (JP, B2)
Claims (1)
アンモニアガス、モルホリン、シクロヘキシルアミン、
モノエタノールアミン、ジエタノールアミンおよびトリ
エタノールアミンからなる群の中から選ばれた少くとも
１種の化合物を添加してpHを6.5〜9.0に調整した洗浄液
に水化ヒドラジンを添加してpHを7.0〜9.5に調整した上
更に腐食抑制剤を添加して得られた混合液により、前処
理工程を含むことなく１工程で鉄系金属面に生成付着し
た難溶性スケールを120℃〜160℃の温度範囲で20時間以
上の処理時間で溶解除去することを特徴とする難溶性ス
ケールの化学的洗浄方法。(1) an aqueous ammonia,
Ammonia gas, morpholine, cyclohexylamine,
Monoethanolamine, diethanolamine and triethanolamine were added to at least one compound selected from the group to adjust the pH to 6.5 to 9.0, and hydrazine hydrate was added to the washing solution to adjust the pH to 7.0 to 9.5. The mixture obtained by adding a corrosion inhibitor to the iron-based metal surface in a single step without a pretreatment step in a temperature range of 120 ° C to 160 ° C. A method for chemically cleaning a poorly soluble scale, wherein the scale is dissolved and removed in a processing time of 20 hours or more.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62316052A JP2625132B2 (en) | 1987-12-16 | 1987-12-16 | Chemical cleaning method for poorly soluble scale |
| EP88107845A EP0299166A1 (en) | 1987-07-17 | 1988-05-16 | Method for removing scale on inner surfaces of boiler tube members |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62316052A JP2625132B2 (en) | 1987-12-16 | 1987-12-16 | Chemical cleaning method for poorly soluble scale |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01159388A JPH01159388A (en) | 1989-06-22 |
| JP2625132B2 true JP2625132B2 (en) | 1997-07-02 |
Family
ID=18072727
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62316052A Expired - Lifetime JP2625132B2 (en) | 1987-07-17 | 1987-12-16 | Chemical cleaning method for poorly soluble scale |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2625132B2 (en) |
Families Citing this family (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6110881A (en) * | 1990-11-05 | 2000-08-29 | Ekc Technology, Inc. | Cleaning solutions including nucleophilic amine compound having reduction and oxidation potentials |
| US6242400B1 (en) | 1990-11-05 | 2001-06-05 | Ekc Technology, Inc. | Method of stripping resists from substrates using hydroxylamine and alkanolamine |
| US6000411A (en) * | 1990-11-05 | 1999-12-14 | Ekc Technology, Inc. | Cleaning compositions for removing etching residue and method of using |
| US5279771A (en) * | 1990-11-05 | 1994-01-18 | Ekc Technology, Inc. | Stripping compositions comprising hydroxylamine and alkanolamine |
| US6121217A (en) | 1990-11-05 | 2000-09-19 | Ekc Technology, Inc. | Alkanolamine semiconductor process residue removal composition and process |
| US7205265B2 (en) | 1990-11-05 | 2007-04-17 | Ekc Technology, Inc. | Cleaning compositions and methods of use thereof |
| DE69333877T2 (en) * | 1992-07-09 | 2006-06-14 | Ekc Technology Inc | A detergent composition containing a redox amine compound |
| JP4911979B2 (en) * | 2006-01-27 | 2012-04-04 | トヨタ自動車株式会社 | Water-soluble cleaning agent |
| US10674570B2 (en) | 2006-02-21 | 2020-06-02 | Goji Limited | System and method for applying electromagnetic energy |
| US8653482B2 (en) | 2006-02-21 | 2014-02-18 | Goji Limited | RF controlled freezing |
| WO2007096877A2 (en) | 2006-02-21 | 2007-08-30 | Rf Dynamics Ltd. | Electromagnetic heating |
| JP5363893B2 (en) * | 2009-07-06 | 2013-12-11 | 中部電力株式会社 | Method for treating ferrous metal surface exposed to superheated steam |
| CN106028495B (en) | 2009-11-10 | 2019-04-16 | 高知有限公司 | Control the apparatus and method of energy |
| JP6013132B2 (en) * | 2012-10-19 | 2016-10-25 | 朝日化学工業株式会社 | Corrosion inhibitor for organic acid cleaning and metal cleaning method using the corrosion inhibitor |
| CN105008589B (en) * | 2013-03-01 | 2017-09-22 | 通用电气公司 | Composition and method for suppressing the corrosion in gas turbine air compressor |
| WO2018116991A1 (en) * | 2016-12-21 | 2018-06-28 | 東洋製罐グループホールディングス株式会社 | Method for decomposing polyoxalate |
| JP6914987B2 (en) * | 2019-04-26 | 2021-08-04 | 三菱パワー株式会社 | Chemical cleaning method and chemical cleaning equipment |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5221456A (en) * | 1975-08-11 | 1977-02-18 | Hiroko Miyoshi | Knitting machine |
| JPS5320252A (en) * | 1977-08-26 | 1978-02-24 | Hitachi Ltd | Position detecting apparatus for mobile body |
-
1987
- 1987-12-16 JP JP62316052A patent/JP2625132B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01159388A (en) | 1989-06-22 |
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