US3132975A - Process for pickling and passivating enclosed structures - Google Patents
Process for pickling and passivating enclosed structures Download PDFInfo
- Publication number
- US3132975A US3132975A US32551A US3255160A US3132975A US 3132975 A US3132975 A US 3132975A US 32551 A US32551 A US 32551A US 3255160 A US3255160 A US 3255160A US 3132975 A US3132975 A US 3132975A
- Authority
- US
- United States
- Prior art keywords
- solution
- pickling
- passivating
- rinsing water
- water
- 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
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28G—CLEANING OF INTERNAL OR EXTERNAL SURFACES OF HEAT-EXCHANGE OR HEAT-TRANSFER CONDUITS, e.g. WATER TUBES OR BOILERS
- F28G9/00—Cleaning by flushing or washing, e.g. with chemical solvents
-
- 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
-
- 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
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
Definitions
- This invention is addressed to pickling and passivating surfaces of ferrous metals which are not exposed for treatment in a conventional manner, and it relates more particularly to a new and improved process for pickling and passivating concealed surfaces of iron base alloys and ferrous metals such as the internal surfaces of enclosed structures of substantial dimension or capacity, as represented by heat exchangers, boilers, gas generators, liquid storage tanks, and other process or storage equipment.
- Removal of the oxides by the pickling acids can be followed immediately by washing with aqueous medium for the removal of the pickling acids from the cleaned surfaces of the metal. Rinsing to remove the pickling solutions can be followed almost immediately either by passivating or by drying to avoid reoxidation of the treated ferrous surface.
- Such rinsing, passivating and drying operations can be easily and quickly carried out when concerned with metallic surfaces measurable in a few square meters or even as many as 10 square meters.
- the problem becomes quite different when one has to process surfaces of several hundreds or thousands of square meters, and especially when such surfaces are not readily accessible, such as when they form the internal surfaces of enclosures which may have a capacity of thousands of cubic meters and when such concealed and inaccessible surfaces have to be substantially completely pickled and passivated.
- a heat exchanger for use in nuclear generation of electrical power wherein such heat exchanger may consist of 24 ferrules 30 meters high, having a volume of 350 cubic meters and an internal surface measurable as 30,000 square meters, all of which is combined in a compact structure connected with access piping of 300 mm. diameter. Because of the size, it is impractical to immerse such structure into a pickling bath. In the alternative, the pickling solutions might be introduced into the interior of the exchanger in amounts to fill the exchanger for reaction until the oxides (rust, scale, soldering flux and the like) have been dissolved or stripped from the metal Walls.
- oxides rust, scale, soldering flux and the like
- rinsing by continuous flow of water through the exchanger would also require a number of hours (such as 8-10 hours) before the water rising from the outlet is free of acids, as evidenced by a neutral pH.
- ferrous ions present evenin low concentration in the rinsing water will flocculate as Fe(OH) when the rinsing water is at a pH of about 5.
- These light flocs of Fe(OH) will deposit on the metallic surfaces and, after drying, will give rise to dust, thereby to interfere with the desirable operation of the apparatus.
- FIG. 1 is a flow sheet illustrating the procedures of this invention.
- the picklingsolution is introduced into the interior of the structure from an inlet in the bottom side until the structure is filled to overflowing. As the pickling solution rises through the structure, air is displaced from the structure in a manner to eliminate the formation of any air pockets, thereby to enable the liquid to come into full contact with all of the surfaces.
- an overflow pipe is provided in the uppermost portion of acids, but it is preferred to make use of a solution of the type described in the French Patent No. 966,785, issued June 12, 1946, to Herbert Manfred Freud, also called Jean Frasch, comprising a mild pickling agent.
- Such mild agents are preferred over strong acids such as hydrochloric acid or sulfuric acid, which tend to liberate hydrogen and induce embrittlement of the steel while also possibly creating gas pockets whereby the pickling solution is expelled from contact with the surface of the metal.
- the time that the pickling solution is allowed to remain in reactive contact with the ferrous surface depends upon the pickling solution employed and the amount of rust or scale to be removed.
- the end point can be determined by titration of the solution at predetermined intervals to determine the increase in the amount of iron in the solution.
- pickling can be considered to be complete. With a pickling solution of the aforementioned patent, this will usually take about 24-48 hours.
- the surfaces are rinsed without exposure of the pickled surfaces to air.
- the rinsing water is circulated through the housing from the top to the bottom so that the housing will always remain filled with liquid, thereby to avoid the formation of voids or gas pockets.
- the incoming rinsing water displaces the pickling solution towards the bottom of the housing, with some dilution possibly taking place. Rinsing is thus continued until the liquid issuing from the bottom side of the housing is practically neutral or at least above a pH of 6. While this will indicate substantially complete removal of acid, the presence of Fe(OH) in the wash water will be indicated by the appearance of a blue coloration due to the formation of Prussian blue upon the addition of potassium ferrocyanide in the Prussian blue test.
- the surface is treated with a compound capable of complexing reaction with the contained Fe(OH) to form a soluble compound which can be removed in subsequent rinses to effect substantially complete cleaning of the surfaces.
- complexing compounds as citrates, tartrates, malates, and so on, can be introduced in solution in aqueous medium in the latter stages of the rinsing operation, or immediately thereafter as a separate rinse.
- the circulation of the complexing solution from the top to the bottom of the housing for displacement of rinsing water without the formation of voids or air pockets is continued until the Prussian blue test with potassium ferrocyanide is negative.
- the complexing cycle is followed by a rinsing cycle to eliminate complexing compounds from the system. This is again accomplished by the circulation of clean Water through the housing, as previously described, in a manner to keep the housing filled with water until the pH of the water issuing from the housing is the same as that of the water introduced.
- the surfaces are then passivated by introduction of a passivating solution into the housing to replace the rinse water, preferably by introduction of the passivating solution through the inlet at the top and drainage of the water from the outlet at the bottom, always keeping the housing filled with aqueous medium.
- a passivating solution into the housing to replace the rinse water, preferably by introduction of the passivating solution through the inlet at the top and drainage of the water from the outlet at the bottom, always keeping the housing filled with aqueous medium.
- passivation use can be made of any of the well known or commercial passivating agents for iron, such as an oxidizing agent in solution, but it is preferred to make use of a dilute solution of an amine or amide acid bichromate.
- passivation has been completed and the surfaces are stabilized against rapid rusting or corrosion, the liquids are drained from the housing for the first time to empty the housing since pickling.
- the Walls of the housing will still be Wet with large amounts of water present as a thin film of a few microns in thickness. It is desirable to effect rapid removal of the water for drying the surfaces before rusting can again take place.
- the opening or openings at the top of the housing are sealed and a suction is drawn from the inlet at the bottom. This operates to draw down liquid. For most efficient use, it is desirable to repeat the suction steps at frequent intervals to provide a pulsating effect whereby as much as of the retained moisture can be drained from the housing in a matter of a few hours.
- Suction drying is followed by complete drying by the circulation of dry oxygen or ozonized oxygen from the bottom of the housing to the top, using a vacuum pump at the top to draw off oxygen to maintain subatmospheric conditions within the housing.
- the evacuation rate should be in excess of the rate of introduction of the oxygen so as to maintain vacuum conditions within the housing, thereby to permit the oxygen completely to penetrate the interior of the housing for contact with the remaining moisture whereby the tnoisture evaporates to saturate the oxygen for removal.
- Desiccation with an oxygen stream is continued until the absence of moisture in the exhaust stream is indicated, as by means of absorbent pellets (such as blue silica gel, which turns red when wet).
- absorbent pellets such as blue silica gel, which turns red when wet.
- the process of pickling and passivating internal ferrous surfaces of massive hollow structures comprising introducing a pickling solution into the structure in an amount completely to fill the structure and in a manner to effect substantially complete removal of air thereby to provide for complete wetting of the interior surfaces of the structure with pickling solution, maintaining the pickling solution in contact with the interior surfaces for a time sufficient to remove rust and corrosion from said surfaces, introducing rinsing water into the structure while simultaneously removing pickling solution, said rinsing water being introduced at a rate at least as great as the rate of removal of the pickling solution whereby the interchange is effected without exposure of the surfaces to air, continuing the introduction of rinsing water until the water issuing from the structure is substantially neutral, introducing a solution containing an agent capable of forming a soluble complex with iron hydroxides remaining within the structure to remove the iron hydroxides from the structure by the introduction of rinsing water for displacement of the complexing solutions, introducing a passivating agent in solution into the structure for replacement of the rin
- step of drying the interior surfaces of the structure after the passivating solution has been drained therefrom comprises creating a vacuum within the structure for the displacement of moisture from the walls of the structure.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Materials Engineering (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Chemistry (AREA)
- Combustion & Propulsion (AREA)
- General Engineering & Computer Science (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
- Preventing Corrosion Or Incrustation Of Metals (AREA)
- Chemical Treatment Of Metals (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR796578A FR1236531A (fr) | 1959-06-04 | 1959-06-04 | Procédé de décapage et passivation de grands ensembles fermés |
Publications (1)
Publication Number | Publication Date |
---|---|
US3132975A true US3132975A (en) | 1964-05-12 |
Family
ID=8715619
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US32551A Expired - Lifetime US3132975A (en) | 1959-06-04 | 1960-05-31 | Process for pickling and passivating enclosed structures |
Country Status (8)
Country | Link |
---|---|
US (1) | US3132975A (pt) |
BE (1) | BE591583A (pt) |
CH (1) | CH394760A (pt) |
DE (1) | DE1155652C2 (pt) |
FR (1) | FR1236531A (pt) |
GB (1) | GB949184A (pt) |
LU (1) | LU38770A1 (pt) |
NL (2) | NL131125C (pt) |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3202551A (en) * | 1961-09-13 | 1965-08-24 | Hoechst Ag | Method for producing adherent coatings on iron and steel parts |
US3368913A (en) * | 1963-01-29 | 1968-02-13 | Henkel & Cie Gmbh | Process for the treatment of metal surfaces prior to enameling |
US3416962A (en) * | 1964-08-05 | 1968-12-17 | Sperry Rand Corp | Preparing etched substances for vacuum deposition of a metal thereon |
US3510351A (en) * | 1964-11-27 | 1970-05-05 | Paul Van Dillen | Method for etching and cleaning of objects and plants,particularly tube systems and boiler plants,consisting of iron or steel |
US3522093A (en) * | 1967-02-27 | 1970-07-28 | Chem Cleaning & Equipment Serv | Processes of cleaning and passivating reactor equipment |
US4045253A (en) * | 1976-03-15 | 1977-08-30 | Halliburton Company | Passivating metal surfaces |
US4707191A (en) * | 1984-03-09 | 1987-11-17 | Societe Nationale D'etude Et De Construction De Moteurs D'aviation (Snecma) | Pickling process for heat-resistant alloy articles |
US6706669B2 (en) | 2001-07-13 | 2004-03-16 | Exxonmobil Research And Engineering Company | Method for inhibiting corrosion using phosphorous acid |
US20040168708A1 (en) * | 2001-05-28 | 2004-09-02 | Franck Rouppert | Method for cleaning surfaces,metallic surfaces in particular |
US20080083435A1 (en) * | 2006-10-06 | 2008-04-10 | Myers Craig W | Method of inhibiting corrosion in storage and transport vessels |
WO2008120236A2 (en) | 2007-03-30 | 2008-10-09 | Dorf Ketal Chemicals (I) Private Limited | High temperature naphthenic acid corrosion inhibition using organophosphorous sulphur compounds and combinations thereof |
WO2008122989A2 (en) | 2007-04-04 | 2008-10-16 | Dorf Ketal Chemicals (I) Private Limited | Naphthenic acid corrosion inhibition using new synergetic combination of phosphorus compounds |
WO2009063496A2 (en) | 2007-09-14 | 2009-05-22 | Dorf Ketal Chemicals (I) Private Limited | A novel additive for naphthenic acid corrosion inhibition and method of using the same |
US20110160405A1 (en) * | 2008-08-26 | 2011-06-30 | Dorf Ketal Chemicals (1) Private Limited | Effective novel polymeric additive for inhibiting napthenic acid corrosion and method of using the same |
US20110214980A1 (en) * | 2008-08-26 | 2011-09-08 | Mahesh Subramaniyam | New additive for inhibiting acid corrosion and method of using the new additive |
US9777230B2 (en) | 2009-04-15 | 2017-10-03 | Dorf Ketal Chemicals (India) Private Limited | Effective novel non-polymeric and non-fouling additive for inhibiting high-temperature naphthenic acid corrosion and method of using the same |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2987754B2 (ja) * | 1996-01-17 | 1999-12-06 | 岩谷産業株式会社 | 高純度ガスの配管路での不動態化処理方法 |
CN103014729A (zh) * | 2012-12-06 | 2013-04-03 | 启东市海鹰阀门有限公司 | 汽车散热器洗涤剂 |
CN105021768A (zh) * | 2014-04-15 | 2015-11-04 | 上海梅山钢铁股份有限公司 | 一种钢板高温酸洗试验装置其使用方法 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2428364A (en) * | 1944-09-21 | 1947-10-07 | Frager Max | Process for providing rust free surfaces on ferrous metal parts |
US2524757A (en) * | 1945-05-17 | 1950-10-10 | Dow Chemical Co | Cleaning scaled vessels |
US2773623A (en) * | 1954-06-01 | 1956-12-11 | Heintz Mfg Co | Corrosion resistant coated steel members and method of making |
US2907689A (en) * | 1949-10-24 | 1959-10-06 | Calvin P Kidder | Method of controlling corrosion in a neutronic reactor |
US3063866A (en) * | 1960-12-02 | 1962-11-13 | Gen Mills Inc | Method of forming bismuth whiskers |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1001560B (de) * | 1952-02-25 | 1957-01-24 | Hivolin GmbH Mulheim/Ruhr | Verfahren und Vorrichtung zur Behandlung von Hohlkoerpersystemen mit Fluessigkeiten,z. B. zum Ausbeizen von Kesselanlagen |
DE1053277B (de) * | 1957-11-30 | 1959-03-19 | Hivolin G M B H | Verfahren zur gleichwirkenden inneren Behandlung von Hohlkoerpersystemen mit Fluessigkeiten, z. B. zum Ausbeizen |
-
0
- NL NL252277D patent/NL252277A/xx unknown
- NL NL131125D patent/NL131125C/xx active
-
1959
- 1959-06-04 FR FR796578A patent/FR1236531A/fr not_active Expired
-
1960
- 1960-05-31 US US32551A patent/US3132975A/en not_active Expired - Lifetime
- 1960-06-02 CH CH631360A patent/CH394760A/fr unknown
- 1960-06-02 GB GB19608/60A patent/GB949184A/en not_active Expired
- 1960-06-03 BE BE591583A patent/BE591583A/fr unknown
- 1960-06-03 DE DE1960S0068822 patent/DE1155652C2/de not_active Expired
- 1960-06-03 LU LU38770D patent/LU38770A1/xx unknown
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2428364A (en) * | 1944-09-21 | 1947-10-07 | Frager Max | Process for providing rust free surfaces on ferrous metal parts |
US2524757A (en) * | 1945-05-17 | 1950-10-10 | Dow Chemical Co | Cleaning scaled vessels |
US2907689A (en) * | 1949-10-24 | 1959-10-06 | Calvin P Kidder | Method of controlling corrosion in a neutronic reactor |
US2773623A (en) * | 1954-06-01 | 1956-12-11 | Heintz Mfg Co | Corrosion resistant coated steel members and method of making |
US3063866A (en) * | 1960-12-02 | 1962-11-13 | Gen Mills Inc | Method of forming bismuth whiskers |
Cited By (24)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3202551A (en) * | 1961-09-13 | 1965-08-24 | Hoechst Ag | Method for producing adherent coatings on iron and steel parts |
US3368913A (en) * | 1963-01-29 | 1968-02-13 | Henkel & Cie Gmbh | Process for the treatment of metal surfaces prior to enameling |
US3416962A (en) * | 1964-08-05 | 1968-12-17 | Sperry Rand Corp | Preparing etched substances for vacuum deposition of a metal thereon |
US3510351A (en) * | 1964-11-27 | 1970-05-05 | Paul Van Dillen | Method for etching and cleaning of objects and plants,particularly tube systems and boiler plants,consisting of iron or steel |
US3522093A (en) * | 1967-02-27 | 1970-07-28 | Chem Cleaning & Equipment Serv | Processes of cleaning and passivating reactor equipment |
US4045253A (en) * | 1976-03-15 | 1977-08-30 | Halliburton Company | Passivating metal surfaces |
US4707191A (en) * | 1984-03-09 | 1987-11-17 | Societe Nationale D'etude Et De Construction De Moteurs D'aviation (Snecma) | Pickling process for heat-resistant alloy articles |
US20040168708A1 (en) * | 2001-05-28 | 2004-09-02 | Franck Rouppert | Method for cleaning surfaces,metallic surfaces in particular |
US6706669B2 (en) | 2001-07-13 | 2004-03-16 | Exxonmobil Research And Engineering Company | Method for inhibiting corrosion using phosphorous acid |
US20080083435A1 (en) * | 2006-10-06 | 2008-04-10 | Myers Craig W | Method of inhibiting corrosion in storage and transport vessels |
US9090837B2 (en) | 2007-03-30 | 2015-07-28 | Dorf Ketal Chemicals (I) Private Limited | High temperature naphthenic acid corrosion inhibition using organophosphorous sulphur compounds and combinations thereof |
US20100126842A1 (en) * | 2007-03-30 | 2010-05-27 | Dorf Ketal Chemicals (I) Private Limited | High temperature naphthenic acid corrosion inhibition using organophosphorous sulphur compounds and combinations thereof |
WO2008120236A2 (en) | 2007-03-30 | 2008-10-09 | Dorf Ketal Chemicals (I) Private Limited | High temperature naphthenic acid corrosion inhibition using organophosphorous sulphur compounds and combinations thereof |
US9228142B2 (en) | 2007-04-04 | 2016-01-05 | Dorf Ketal Chemicals (I) Private Limited | Naphthenic acid corrosion inhibition using new synergetic combination of phosphorus compounds |
US20100116718A1 (en) * | 2007-04-04 | 2010-05-13 | Dorf Ketal Chemicals (1) Private Limited | Naphthenic acid corrosion inhibition using new synergetic combination of phosphorus compounds |
WO2008122989A2 (en) | 2007-04-04 | 2008-10-16 | Dorf Ketal Chemicals (I) Private Limited | Naphthenic acid corrosion inhibition using new synergetic combination of phosphorus compounds |
US20100264064A1 (en) * | 2007-09-14 | 2010-10-21 | Dorf Ketal Chemicals (1) Private Limited | novel additive for naphthenic acid corrosion inhibition and method of using the same |
WO2009063496A2 (en) | 2007-09-14 | 2009-05-22 | Dorf Ketal Chemicals (I) Private Limited | A novel additive for naphthenic acid corrosion inhibition and method of using the same |
US9115319B2 (en) | 2007-09-14 | 2015-08-25 | Dorf Ketal Chemicals (I) Private Limited | Additive for naphthenic acid corrosion inhibition and method of using the same |
US20110160405A1 (en) * | 2008-08-26 | 2011-06-30 | Dorf Ketal Chemicals (1) Private Limited | Effective novel polymeric additive for inhibiting napthenic acid corrosion and method of using the same |
US20110214980A1 (en) * | 2008-08-26 | 2011-09-08 | Mahesh Subramaniyam | New additive for inhibiting acid corrosion and method of using the new additive |
US9890339B2 (en) | 2008-08-26 | 2018-02-13 | Dorf Ketal Chemicals (I) Private Limited | Additive for inhibiting acid corrosion and method of using the new additive |
US10787619B2 (en) | 2008-08-26 | 2020-09-29 | Dorf Ketal Chemicals (India) Private Limited | Effective novel polymeric additive for inhibiting napthenic acid corrosion and method of using the same |
US9777230B2 (en) | 2009-04-15 | 2017-10-03 | Dorf Ketal Chemicals (India) Private Limited | Effective novel non-polymeric and non-fouling additive for inhibiting high-temperature naphthenic acid corrosion and method of using the same |
Also Published As
Publication number | Publication date |
---|---|
FR1236531A (fr) | 1960-07-22 |
GB949184A (en) | 1964-02-12 |
LU38770A1 (pt) | 1960-12-03 |
NL131125C (pt) | |
CH394760A (fr) | 1965-06-30 |
DE1155652B (de) | 1963-10-10 |
DE1155652C2 (de) | 1974-11-21 |
BE591583A (fr) | 1960-12-05 |
NL252277A (pt) |
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