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
  • 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
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B08—CLEANING
  • B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
  • B08B9/00—Cleaning hollow articles by methods or apparatus specially adapted thereto
  • B08B9/08—Cleaning containers, e.g. tanks
  • B08B9/0804—Cleaning containers having tubular shape, e.g. casks, barrels, drums
  • B08B9/0813—Cleaning containers having tubular shape, e.g. casks, barrels, drums by the force of jets or sprays
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B08—CLEANING
  • B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
  • B08B9/00—Cleaning hollow articles by methods or apparatus specially adapted thereto
  • B08B9/08—Cleaning containers, e.g. tanks
  • B08B9/0821—Handling or manipulating containers, e.g. moving or rotating containers in cleaning devices, conveying to or from cleaning devices
  • B08B9/0826—Handling or manipulating containers, e.g. moving or rotating containers in cleaning devices, conveying to or from cleaning devices the containers being brought to the cleaning device
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B08—CLEANING
  • B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
  • B08B9/00—Cleaning hollow articles by methods or apparatus specially adapted thereto
  • B08B9/08—Cleaning containers, e.g. tanks
  • B08B9/093—Cleaning containers, e.g. tanks by the force of jets or sprays
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B08—CLEANING
  • B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
  • B08B9/00—Cleaning hollow articles by methods or apparatus specially adapted thereto
  • B08B9/08—Cleaning containers, e.g. tanks
  • B08B9/20—Cleaning containers, e.g. tanks by using apparatus into or on to which containers, e.g. bottles, jars, cans are brought
  • B08B9/28—Cleaning containers, e.g. tanks by using apparatus into or on to which containers, e.g. bottles, jars, cans are brought the apparatus cleaning by splash, spray, or jet application, with or without soaking
  • B08B9/34—Arrangements of conduits or nozzles
• • 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
  • C23G3/00—Apparatus for cleaning or pickling metallic material

Definitions

• the present invention relates to a method of surface treatment of a metal container having at least one orifice, said method being more particularly intended for the pickling of containers made up of assembled sheets by welding, crimping, riveting, bonding, etc.
• Such containers are, for example, drums, fixed or mobile tanks, storage silos, tanks, tanks for heating domestic water, and generally all the hollow bodies.
• the orifice to which reference is made may, for example, be intended to receive pipes, a filling, heating or evacuation system.
• the container is assembled by welding, the area most affected by this contamination is the weld bead.
• the object of the present invention is therefore to provide a surface treatment method which does not have the drawbacks of the prior art and which makes it possible in particular to treat metal containers without generating large quantities of toxic effluents, in complete safety for operators, and with improved and high productivity.
• a first object of the present invention is constituted by a method of surface treatment of a metal container having at least one orifice, by at least one treatment solution, characterized in that it comprises the steps consisting in :
• said container in a treatment enclosure in such a way that its orifice faces downwards, said enclosure comprising a plurality of nozzles for spraying said solution under pressure and at least one receiving tank,
• the method according to the invention can also include the following variants, taken individually or in combination:
• the treatment solution can be sprayed at a pressure higher than 10 bar
• the treatment solution is sprayed at a pressure below 90 bar
• the pickling solution can contain at least one acid chosen from a halogen acid, an organic acid and a mineral acid,
• the halogen acid can be hydrofluoric acid
• the mineral acid can be sulfuric or phosphoric acid
• the organic acid can be a peroxygenated acid, in particular peracetic acid
• the container or hollow body to be treated can be made of cast iron, steel, stainless steel, titanium, zirconium, copper, nickel, or their alloys, and preferably cast iron, steel or stainless steel, and more preferably stainless steel,
• the redox potential of the pickling solution is maintained at a predetermined value, located above the normal potential of species in solution, preferably 100 mV above, and more particularly 150 mV above,
• the metal container can be obtained by welding sheets
• the metal container can be a hot water tank, but also a vinification tank, a tank for the transport of food or chemical products, for example.
• a second object of the invention consists of a device for treating the surface of a metal container having at least one orifice, which comprises a treatment enclosure provided with at least one receiving tank, means for holding said container, means for spraying a treatment solution into said enclosure and inside said container, means for recirculating said solution between said tank and said spraying means, said recirculating means comprising a pump for supplying said means of projection at a pressure higher than 8 bar.
• a third object of the invention consists of a surface treatment line of a metal container having at least one orifice, comprising a device according to the invention, and further comprising a conveyor chain feeding said device with said metal containers.
• the device according to the invention can also include the following variants, taken individually or in combination:
• control means comprising at least one measurement probe, in particular of the temperature, of the concentration of H + ions, or of the redox potential of the treatment solution, implanted at any point of the recirculation circuit of the solution ,
• the device includes a system for suction and condensation of acid vapors.
• the method according to the invention can be applied to any metallic surface, and in particular to cast iron, steel, alloy steels, ferrous alloys, nickel and its alloys, chromium and its alloys, titanium and its alloys, zirconium and its alloys, as well as copper and its alloys.
• the present inventors have found that spraying a pickling solution at a pressure greater than 8 bar, and preferably greater than 10 bar, makes it possible to obtain pickling times divided at least by 6, compared to methods of 'immersion in tanks.
• the projection of the pickling solution makes it possible to crack the calamines and then inject the solution into its cracks. This mechanical action is associated with a chemical action by a percolation - chemical dissolution mechanism.
• the pickling solution at a pressure of less than 90 bar.
• the rate of supply of the solution also makes it possible to reduce the diffusion limit layer by accelerating the renewal of the acid solution on the surface of the container.
• the device according to the invention as shown in Figure 1 comprises an enclosure 1 which can be made gas and liquid tight vis-à-vis the outside of the device.
• this enclosure 1 is installed a plate (not shown) provided with a receiving tank 2 connected to a system for recovering a treatment solution.
• the enclosure 1 also includes a lower projection nozzle 3 intended for the treatment of the internal part of a metal container 4, as well as a series of nozzles 5, 5 ', 5 "in the upper part of the enclosure 1 and intended for the treatment of the external part of the container 4.
• the enclosure 1 can further comprise a system for suction and condensation of acid vapors (not shown), as well as a heating system for the enclosure 1 with automatic regulation.
• It comprises at least one receiving tank 2, but can contain as many as there are different treatment solutions, which can make it possible to collect each solution in a specific tank and therefore to facilitate its recycling and / or its recirculation in the 'pregnant.
• Means can also be provided for adding reagents to this enclosure 1, as well as sensors 6, 6 ′, 6 ′′ making it possible to monitor the good progress of the surface treatment.
• sensors 6, 6 ′, 6 can be installed at different locations on the device and in particular in the receiving tank 2 or on the circuit for collecting the solution which has just been sprayed under pressure, but also outside the enclosure. 1 in a solution preparation tank.
• sensors 6, 6 ′, 6 “measuring the redox potential, the H + concentration, the temperature, or any other sensor which can make it possible to determine whether the solution must be treated before being used.
• This device is therefore intended for treating the surface of a metal container 4 comprising at least one orifice 4 '.
• This container is introduced into the enclosure 1 and arranged so that its orifice 4 'is oriented downwards.
• the lower projection nozzle 3 is inserted through the orifice 4 ′, inside the container 4, then a pickling solution is sprayed at a pressure higher than 8 bar, and at a temperature comprised, for example, between 40 and 70 ° C.
• a pickling solution which can be used in the process according to the invention may comprise an acid or a mixture of mineral acids comprising a halogen compound or a sulphate, orthophosphate or metaphosphate radical, or alternatively an acid or a mixture of aliphatic organic acids or cyclic, such as a peroxygenated acid such as peracetic acid, or acid Perboric.
• This solution can also include mixtures of acids of different nature, such as a mixture of halogen acid and mineral acid, for example.
• Peroxygenated acid can also be obtained in situ by adding hydrogen peroxide to an organic acid.
• the use of these peroxygenated acids is particularly advantageous, since the pickling solutions containing them can be eliminated by simple combustion without release of toxic gases.
• the concentration of acids is preferably between 0.1 and 7 moles per liter, and more preferably between 0.1 and 6 moles per liter, while the concentration of metals in the solution is preferably between 0 , 2 and 2 moles per liter.
• This pickling solution also comprises an oxidized compound originating from the metal constituting the container to be treated at its maximum valence.
• This compound can also be combined with the pickling solution by dissolving a synthetic salt in the solution or by the action of hydrogen peroxide, ozone or persalts.
• the composition of the solution will be adapted to the composition and to the constitution of the oxides to be eliminated.
• the redox potential will be chosen so as to be greater than the redox potential of the redox couple of the main constituent, in an oxidizing / reducing molar ratio greater than or equal to 4, in the medium considered.
• the temperature of the solution is preferably between 40 ° C and 80 ° C, and more particularly preferably, of the order of 60 ° C, more or less 2 ° C.
• the solution spraying rate is regulated so as to balance the emptying rate in the enclosure.
• the container Before or after spraying this pickling solution, the container can be rinsed with hot (60 ° C) or cold (15 ° C) aqueous solutions, for example. It can also be passivated by hydrogen peroxide diluted in an acid medium, or any other solution (persalts, etc.).
• hot (60 ° C) or cold (15 ° C) aqueous solutions for example. It can also be passivated by hydrogen peroxide diluted in an acid medium, or any other solution (persalts, etc.).

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Materials Engineering (AREA)
• General Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Organic Chemistry (AREA)
• Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
• Other Surface Treatments For Metallic Materials (AREA)
• Application Of Or Painting With Fluid Materials (AREA)
• Chemical Treatment Of Metals (AREA)
• Chemically Coating (AREA)
• ing And Chemical Polishing (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

Family

ID=33443134

Family Applications (1)

Country Status (10)

Cited By (4)

Families Citing this family (6)

Citations (4)

• 2003
  • 2003-06-04 FR FR0306744A patent/FR2855773B1/fr not_active Expired - Fee Related
• 2004
  • 2004-05-17 DK DK04742760T patent/DK1633499T3/da active
  • 2004-05-17 EP EP04742760A patent/EP1633499B1/de not_active Expired - Lifetime
  • 2004-05-17 ES ES04742760T patent/ES2313028T3/es not_active Expired - Lifetime
  • 2004-05-17 SI SI200430930T patent/SI1633499T1/sl unknown
  • 2004-05-17 WO PCT/FR2004/001212 patent/WO2004108309A1/fr not_active Ceased
  • 2004-05-17 PT PT04742760T patent/PT1633499E/pt unknown
  • 2004-05-17 DE DE602004017169T patent/DE602004017169D1/de not_active Expired - Lifetime
  • 2004-05-17 AT AT04742760T patent/ATE411119T1/de active
• 2005
  • 2005-12-05 NO NO20055761A patent/NO329293B1/no not_active IP Right Cessation

Patent Citations (4)

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