EP1421165B1 - Method for treating a surface with a treating gel and treating gel - Google Patents

Method for treating a surface with a treating gel and treating gel Download PDF

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Publication number
EP1421165B1
EP1421165B1 EP02760387A EP02760387A EP1421165B1 EP 1421165 B1 EP1421165 B1 EP 1421165B1 EP 02760387 A EP02760387 A EP 02760387A EP 02760387 A EP02760387 A EP 02760387A EP 1421165 B1 EP1421165 B1 EP 1421165B1
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EP
European Patent Office
Prior art keywords
gel
treatment
weight
mixture
inorganic
Prior art date
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EP02760387A
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German (de)
French (fr)
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EP1421165A1 (en
Inventor
Sylvain Faure
Bruno Fournel
Paul Fuentes
Yvan Lallot
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Orano Demantelement SAS
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Commissariat a lEnergie Atomique CEA
Compagnie Generale des Matieres Nucleaires SA
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    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21F—PROTECTION AGAINST X-RADIATION, GAMMA RADIATION, CORPUSCULAR RADIATION OR PARTICLE BOMBARDMENT; TREATING RADIOACTIVELY CONTAMINATED MATERIAL; DECONTAMINATION ARRANGEMENTS THEREFOR
    • G21F9/00—Treating radioactively contaminated material; Decontamination arrangements therefor
    • G21F9/001—Decontamination of contaminated objects, apparatus, clothes, food; Preventing contamination thereof
    • G21F9/002—Decontamination of the surface of objects with chemical or electrochemical processes
    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D17/00—Detergent materials or soaps characterised by their shape or physical properties
    • C11D17/0008—Detergent materials or soaps characterised by their shape or physical properties aqueous liquid non soap compositions
    • C11D17/003—Colloidal solutions, e.g. gels; Thixotropic solutions or pastes
    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
    • C11D3/02—Inorganic compounds ; Elemental compounds
    • C11D3/04—Water-soluble compounds
    • C11D3/042—Acids
    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
    • C11D3/02—Inorganic compounds ; Elemental compounds
    • C11D3/04—Water-soluble compounds
    • C11D3/046—Salts
    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
    • C11D3/02—Inorganic compounds ; Elemental compounds
    • C11D3/12—Water-insoluble compounds
    • C11D3/124—Silicon containing, e.g. silica, silex, quartz or glass beads
    • 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
    • C23G1/025—Cleaning or pickling metallic material with solutions or molten salts with acid solutions acidic pickling pastes
    • 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

Definitions

  • the present invention relates to a method of treating a surface with a gel, as well as to a treatment gel that can be used in such a process.
  • the treatment may be for example a decontamination treatment, for example radioactive or organic, a pickling treatment or a degreasing treatment of a surface.
  • the gels of the prior art do not dry or in several tens of hours and must all be removed after a few hours by rinsing with water.
  • the rinsing also makes it possible to interrupt the action of the gel on the wall and to control the duration of action of the gel.
  • Rinsing has the disadvantage of generating liquid effluents of the order of 10 L of water per kg of gel used. These decontamination effluents in the case of radioactive decontamination are treated in existing nuclear material treatment facilities. This requires in-depth studies on the management of these effluents and their impact vis-à-vis the facilities treatment circuits. In addition such gels that must be rinsed can not be used to treat installation surfaces that must not be flooded.
  • the present invention is specifically intended to provide a method of treating a surface with a gel, and a treatment gel for use in such a process, which overcomes the aforementioned drawbacks of the prior art.
  • the gel dries by fracturing.
  • concentrations are expressed in moles per liter of gel in the present text.
  • the gel drying temperature in the treatment process is between 20 and 30 ° C, and the relative humidity between 20% and 70%.
  • AEROSIL fumed silicas "Cab-O-Sil” M5, H5 or EH5 (trademarks) marketed by CABOT and pyrogenic silicas marketed by Degussa under the name AEROSIL (trademarks).
  • fumed silicas AEROSIL 380 (trade mark) silica with a specific surface area of 380 m 2 / g, which offers the maximum viscosity properties for a minimum mineral filler, will be preferred.
  • the precipitated silica may be obtained, for example, by mixing a solution of sodium silicate and an acid.
  • the preferred precipitated silicas are marketed by DEGUSSA under the name SIPERNAT 22 LS and FK 310 (trademarks).
  • the viscosifying agent of the gel of the present invention is therefore a mixture of the two types of silicas mentioned above, pyrogenated and precipitated.
  • the mixture of the silicas is preferably at a concentration of 5 to 10% by weight of the gel to ensure drying of the gel at a temperature of between 20 ° C. and 30 ° C. and relative humidity of between 20 and 70% on average at 2 ° to 5 hours. Indeed, such a mixture unexpectedly influences the drying of the gel and the particle size of the residue obtained.
  • the dry gel is in the form of particles of controlled size ranging from 0.1 to 2 mm thanks in particular to the aforementioned compositions of the present invention.
  • a precipitated silica for example FK 310 (trademarks)
  • an 8% silica gel for example AEROSIL 380 (trademarks)
  • the active treatment agent may be an acid or a mixture of inorganic acids, preferably selected from hydrochloric acid, nitric acid, sulfuric acid and phosphoric acid or a mixture thereof.
  • the acid is preferably present at a concentration of 0.1 to 7 mol / l, more preferably 0.5 to 4 mol / l, to ensure drying of the gel at a temperature between 20 ° C and 30 ° C and relative humidity between 20 and 70% on average in 2 to 5 hours.
  • the treatment gel according to the invention may also contain, as active treatment agent, a base, preferably a mineral base preferably chosen from sodium hydroxide, potassium hydroxide or mixtures thereof.
  • a base preferably a mineral base preferably chosen from sodium hydroxide, potassium hydroxide or mixtures thereof.
  • the base is advantageously present at a concentration of less than 2 mol / l, preferably between 0.5 and 2 mol / l, more preferably between 1 and 2 mol / l to ensure drying of the gel at a temperature of between 20 ° C. and 30 ° C and relative humidity between 20 and 70% on average in 2 to 5 hours
  • the gel of the invention may contain an oxidizing agent, for example at a concentration of 0.5 to 1 mol / l, which has a normal oxidation-reduction potential greater than 1400 mV in a strong acid medium, that is to say, an oxidizing power greater than that of permanganate.
  • an oxidizing agent for example, such oxidizing agents may be Ce (IV) Co (III) and Ag (II).
  • the oxidizing agents are generally associated with a mineral acid, such as nitric acid at a moderate concentration of less than 2 mol / l, and allowing rapid drying of the gel.
  • Cerium is generally introduced in the form of electrogenerated cerium (IV) nitrate Ce (NO 3 ) 4 or hexanitrate cerium (NH 4 ) 2 Ce (NO 3 ) 5 .
  • a typical example of an oxidizing decontamination gel according to the invention consists of a colloidal solution comprising 0.1 to 0.5 mol / l of This (NO 3 ) 4 or (NH 4 ) 2 Ce (NO 3 ) 6 , from 0.5 to 2 mol / l of nitric acid and from 5 to 15% by weight of silica.
  • the gels of the invention can easily be prepared at room temperature by adding to an aqueous solution the mineral gelling agent consisting of the silica mixture which preferably has a high specific surface area, for example greater than 100 m 2 / g. .
  • a viscosity of at least 350 mPa.s and a viscosity recovery time of less than one second are preferred so that the gel can be sprayed, remotely or not, on the surface to be treated without pouring.
  • the objective of the present invention is therefore also to provide gels with controlled duration of action by a fast drying time, sufficient to ensure the treatment of the surface, usually between 2 and 5 hours, and even between 2 and 3 hours at a temperature between 20 ° C and 30 ° C and average relative humidity between 20 and 70%.
  • the gels according to the invention comprise a mixture of viscosifying agents and an active decontamination agent at the above concentrations, the drying of the gel leads to a dry residue having an ability to easily detach from the support. Thus, no rinsing with water is necessary and the process thus generates no secondary effluent.
  • the gels of the present invention can be generally described as colloidal solutions comprising a mixture of silicas and an active treatment agent, for example an acid, a base, an oxidizing agent, a reducing agent or a mixture thereof, which is chosen in particular according to the nature of the treatment and the surface to be treated.
  • an active treatment agent for example an acid, a base, an oxidizing agent, a reducing agent or a mixture thereof, which is chosen in particular according to the nature of the treatment and the surface to be treated.
  • an alkaline gel having degreasing properties can be used.
  • the removal of a hot and cold-fixed contamination on a stainless steel surface can be done by means of an oxidizing gel.
  • the dissolution of oxide layers can be done by means of a reducing gel which will preferably be used in addition to the oxidizing gel and alternately.
  • a cold-fixed contamination on a ferritic steel can be removed for example by means of an acid gel.
  • the gel may be applied to the surface to be treated by conventional methods such as spraying with a spray gun or with a brush, for example a brush to be decontaminated.
  • the viscous colloidal solution may for example be conveyed via a low pressure pump ( ⁇ 7 bars) and the bursting of the gel jet on the surface may be obtained with a flat or round nozzle.
  • the sufficiently short viscosity recovery time allows the sprayed gel to adhere to the wall.
  • the amounts of gel deposited on the surface to be treated are generally 100 to 2000 g / m 2 , preferably 100 to 1000 g / m 2 , more preferably 300 to 700 g / m 2 . They influence the drying time of the gel.
  • the drying time of the gel of the present invention depends mainly on its composition within the concentration ranges defined above. It is generally between 2 and 5 hours, more precisely between 2 and 3 hours, at a temperature of between 20 ° C. and 30 ° C. and a mean relative humidity of between 20 and 70%.
  • the dry residue obtained after drying can be easily removed, for example by brushing and / or suction, but also by gas jet, for example compressed air.
  • the treatment of the surface can be renewed each time with the same gel or with gels of different nature during the different successive stages, each of these steps including the application of the gel, the maintenance of the gel on the surface during the treatment of the surface and its drying, as well as the removal of the dry residue obtained.
  • the present invention is generally applicable to the treatment, for example of decontamination, of metal surfaces, important or not, which are not necessarily horizontal, but which can be inclined or even vertical.
  • Treatment means any surface treatment for cleaning, decontaminate or etch said surface. It may be for example a radioactive or organic decontamination treatment (eg removal of microorganisms, parasites etc ...), a pickling treatment for removing oxides or a degreasing treatment of a surface.
  • a radioactive or organic decontamination treatment eg removal of microorganisms, parasites etc
  • a pickling treatment for removing oxides or a degreasing treatment of a surface.
  • the present invention can be used to treat all kinds of surfaces such as metal surfaces, plastic surfaces, vitreous material surfaces, etc.
  • compositions of the gels of the present invention according to the surface to be treated and the treatment to be carried out.
  • the present invention may advantageously be used for example in the nuclear field for decontaminating tanks, ventilation ducts, storage pools, glove boxes, etc. It can be used both for periodic maintenance of existing installations and for the remediation of installations.
  • the present invention thus also relates to a method for decontaminating an installation.
  • the decontamination process can comprise a dedusting of the installation to be treated, followed by a treatment of the installation at by means of a treatment method according to the present invention.
  • the dedusting of the installation to be treated can be achieved for example by brushing, blowing or dust extraction to remove solid unbound contamination.
  • This pretreatment can be carried out for example on the stainless steel ventilation ducts of nuclear installations which contain large quantities of dust.
  • the treatment method of the present invention can then be used by applying one or more gel passes of the invention to remove the contamination attached to the inner walls of the sheaths.
  • the gels dry completely after having acted on the surface and are easily detached from the wall by suction.
  • Te represents the evaporation rate as a percentage of the initial quantity of solvent
  • ts the drying time in minutes
  • T the drying temperatures for each curve in ° C
  • Hr the relative humidity level during the different tests expressed as a percentage.
  • the amount of gel deposited on the surface had only a slight influence on the drying characteristics and more particularly on the detachability. Different amounts of gel ranging from 0.1 to 2 kg of gel per m 2 were deposited on surfaces. The amounts of about 0.3 kg.m -2 to about 0.7 kg.m -2 are preferred.
  • the drying conditions are the most important parameters in the process of the present invention. Among them is the drying temperature and the moisture content of the drying air. The existence of a convective current is also important. The influence of these parameters was assessed quantitatively by plotting drying charts.
  • the temperature range which is retained is 20 ° C to 30 ° C and the relative humidity range of drying air 20% to 70%, the relative humidity being defined as the ratio of the vapor pressure of water at a given temperature at the saturation vapor pressure of the water at the same temperature.
  • New 304 L stainless steel parts are gel coated.
  • the amount of gel deposited is 0.5 kg.m -2 ( ⁇ 5%) for the following tests when this is not specified.
  • the silicas are pre-mixed in a cylindrical beaker tours.min 800 -1 using a propeller stirrer to ensure intimate mixing of the silica.
  • When preparing the gel was stirred at 500 tours.min -1 by the same stirring system.
  • Coated samples are placed in a climatic chamber at controlled temperature and humidity.
  • the climate chamber is a KBF trademark with a volume of 115 liters.
  • Humidity control is provided by steam injection generated by the passage of an electric current through humidifier.
  • the speed of the convective current at the surface of the samples can be considered as identical for all the cases and of very low intensity.
  • the mass of the coating over time is monitored for each set temperature / humidity pair.
  • the curves obtained have the same pace as at 30 ° C. However, the drying times are lengthened.
  • the total drying is obtained at 35% humidity in a time of the order of 5 hours. Considering the test carried out at 30 ° C it is determined by extrapolation that with a relative humidity of 20% the total drying time for this value at 25 ° C is between 3 hours and 5 hours. At 50% humidity the extrapolated total drying time is 9 hours which remains acceptable in a surface treatment process.
  • the test carried out in the DEMETER cell is superimposed with the test carried out at 42% relative humidity in the climatic chamber. This allows to derive a pair of values representative of the atmosphere of an armored cell, ie approximately 20 ° C. and 42% relative humidity. This analogy does not take into account a possible deviation of the convection between the climatic chamber and the armored cell.
  • FIG. 4 gathers curves made for three quantities of gel deposited at 20 ° C. and at 42% relative humidity.
  • the humidity levels plotted on the ordinate vary in proportion to the drying speed.
  • the direct comparison of one temperature with the other is not possible because the characteristic times retained are not identical for all the temperatures.
  • the drying charts set forth in this example allow the drying times required during an application of the process of the present invention to be provided provided that the air temperature of the sheath and its relative humidity are known.
  • the area representative of the atmosphere of an armored cell was estimated centered around the following values: temperature: 20 ° C and relative humidity: 40%. These values were obtained by analogy by carrying out a drying test in the DEMETER (trademark) cell.
  • the charts show good compatibility as soon as the temperature is above 20 ° C and the humidity is below about 40%. For lower temperatures or higher humidities, it may be necessary to implement a convective regime in the sheath which can be achieved with a half-speed operation.
  • AEROSIL 380 (trademark) which is a fumed silica with a high specific surface area of 380 m 2 / g, and from 0.5% to 1% by weight of precipitated silica FK 310 (trademark).
  • the present invention provides a gel having characteristics similar to those of a conventional decontamination gel as long as it is not dry in terms of contact time and composition.
  • the gel when the gel is dry, its residues are of controlled size relatively independently of the drying characteristics thanks to the addition of precipitated silica.
  • the advantages are in particular the absence of pulverulent residue, the sizes obtained being of the order 0.1 to 3 mm, facilitating the debondability of the surface residue, and recovery by brushing or aspiration.
  • AEROSIL 380 (trade mark) silica gels and a mixture of nitric acid and phosphoric acid were prepared.
  • the concentration of each of the two acids is preferably less than 2 mol / l. Beyond this, the gel does not dry at a temperature of 25 ° C and a relative humidity of 40%. For a concentration of each of the two acids of between 1 and 2 M, the drying times observed at a temperature of 25 ° C and a relative humidity of 40% vary between 2 and 4 hours.
  • a gel (HNO 3 1M / H 3 PO 4 1M) was in particular prepared and tested in terms of decontamination on aluminum flanges from a pneumatic transfer network of a nuclear waste reprocessing plant.
  • Decontamination factors of the order of 14 (Cs 137, Eu 154) were obtained after a single gel pass (Cs 137: from 1300 Bq / cm 2 to 110 Bq / cm 2 ) and the surface activity was be lowered below 50 Bq / cm 2 with an extra pass.
  • an oxidizing gel according to the invention was prepared using 3 M nitric acid and 0.1 to 0.3 M Ce (IV). ).
  • the gels dry quickly in less than 3 hours and easily peel off with a brush.
  • the corrosion results obtained by coating 500 g / m2 on inconel are quite interesting since generalized erosion is effect between 0.1 and 0.3 ⁇ m.

Abstract

Surface treatment gel comprises a colloidal solution containing 5-25 wt.% of an inorganic viscosifier, 0.1-7 mole/l of a treatment agent and optionally 0.05-1 mole/l of an oxidizing agent having a redox potential above 1.4 V in strong acids, or the reduced form of such an oxidizing agent. An Independent claim is also included for a method for treating a surface, comprising applying a treatment gel as above to the surface, maintaining the gel at a temperature and relative humidity such that the gel dried and has time to treat the surface before forming a dry solid residue, and removing the residue from the surface.

Description

DOMAINE TECHNIQUETECHNICAL AREA

La présente invention se rapporte à un procédé de traitement d'une surface par un gel, ainsi qu'à un gel de traitement utilisable dans un tel procédé.The present invention relates to a method of treating a surface with a gel, as well as to a treatment gel that can be used in such a process.

Le traitement peut être par exemple un traitement de décontamination, par exemple radioactive ou organique, un traitement de décapage ou un traitement de dégraissage d'une surface.The treatment may be for example a decontamination treatment, for example radioactive or organic, a pickling treatment or a degreasing treatment of a surface.

Il peut être utilisé sur toutes sortes de surfaces à traiter, telles que des surfaces métalliques, des surfaces en matières plastiques, des surfaces de matériaux vitreux etc...It can be used on all kinds of surfaces to be treated, such as metal surfaces, plastic surfaces, vitreous materials surfaces, etc.

ETAT DE LA TECHNIQUE ANTERIEURESTATE OF THE PRIOR ART

Les gels de l'art antérieur ne sèchent pas ou en plusieurs dizaines d'heures et doivent tous être éliminés au bout de quelques heures par rinçage à l'eau. Le rinçage permet aussi d'interrompre l'action du gel sur la paroi et de contrôler la durée d'action du gel.The gels of the prior art do not dry or in several tens of hours and must all be removed after a few hours by rinsing with water. The rinsing also makes it possible to interrupt the action of the gel on the wall and to control the duration of action of the gel.

Le rinçage présente l'inconvénient de générer des effluents liquides de l'ordre de 10 L d'eau par kg de gel utilisé. Ces effluents de décontamination lorsqu'il s'agit de décontamination radioactive sont traités dans les installations existantes de traitement de matières nucléaires. Ceci impose donc des études approfondies sur la gestion de ces effluents et sur leur impact vis-à-vis des circuits de traitement des installations. En outre de tels gels qui doivent être rincés ne peuvent pas être utilisés pour traiter des surfaces d'installation qui ne doivent pas être inondées.Rinsing has the disadvantage of generating liquid effluents of the order of 10 L of water per kg of gel used. These decontamination effluents in the case of radioactive decontamination are treated in existing nuclear material treatment facilities. This requires in-depth studies on the management of these effluents and their impact vis-à-vis the facilities treatment circuits. In addition such gels that must be rinsed can not be used to treat installation surfaces that must not be flooded.

Les documents FR-A-2 380 624, EP-A-0 589 781 et FR-A-2 656 949 décrivent des gels de décontamination de surface. Ces gels sont à base de silice ou d'alumine. Ces documents ne décrivent pas de gel pour lesquels la durée de séchage, le décollement des résidus secs de gel de la surface et la taille de ces résidus sont contrôlés.Documents FR-A-2 380 624, EP-A-0 589 781 and FR-A-2 656 949 describe surface decontamination gels. These gels are based on silica or alumina. These documents do not describe gel for which the drying time, the detachment of dry gel residues from the surface and the size of these residues are controlled.

EXPOSE DE L'INVENTIONSUMMARY OF THE INVENTION

La présente invention a précisément pour but de fournir un procédé de traitement d'une surface par un gel, ainsi qu'un gel de traitement utilisable dans un tel procédé, qui surmonte les inconvénients précités de l'art antérieur.The present invention is specifically intended to provide a method of treating a surface with a gel, and a treatment gel for use in such a process, which overcomes the aforementioned drawbacks of the prior art.

Le procédé de traitement comprend dans cet ordre les étapes suivantes :

  • application du gel de traitement sur la surface à traiter, le gel de traitement étant le gel de traitement de la présente invention tel que défini ci-dessous,
  • maintien du gel de traitement sur la surface à traiter à une température et humidité relative telles que le gel sèche et qu'il ait le temps de traiter la surface avant de former un résidu sec et solide, et
  • élimination du résidu sec et solide de la surface traitée.
The treatment method comprises in this order the following steps:
  • applying the treatment gel to the surface to be treated, the treatment gel being the treatment gel of the present invention as defined below,
  • maintaining the treatment gel on the surface to be treated at a temperature and relative humidity such that the gel is dry and that it has time to treat the surface before forming a dry and solid residue, and
  • removing the dry and solid residue from the treated surface.

De préférence, selon l'invention, le gel sèche en se fracturant.Preferably, according to the invention, the gel dries by fracturing.

Les intérêts d'un tel traitement, dit par gel « aspirable », par rapport aux traitements de l'art antérieur sont nombreux. D'abord, il présente les avantages des traitements par gel. Par exemple, il permet d'éviter lors d'une décontamination sur place » d'installations radioactives, les projections de solutions aqueuses produisant de grandes quantités d'effluents radioactifs pour une efficacité limitée en raison du faible temps de contact avec les pièces.The interests of such a treatment, said by "aspirable" gel, compared to the treatments of the prior art are numerous. First, it presents the benefits of gel treatments. For example, it avoids during on-site decontamination of radioactive installations, the projections aqueous solutions producing large quantities of radioactive effluents for limited efficiency due to the short time of contact with the parts.

Ensuite, il permet d'éviter l'opération classique de rinçage du gel par l'eau ou un autre liquide et ne produit ainsi aucun effluent liquide à traiter par la suite. Il en découle une diminution de la quantité d'effluents et une simplification en terme de filière globale de traitement par exemple de décontamination.Then, it avoids the conventional operation of rinsing the gel with water or other liquid and thus produces no liquid effluent to be treated later. This results in a decrease in the amount of effluents and a simplification in terms of global treatment system, for example decontamination.

Le gel de traitement de la présente invention est constitué d'une solution colloïdale comprenant :

  • 5 à 25% en poids, de préférence de 5 à 15% en poids, par rapport au poids du gel, d'un mélange de silice pyrogénée et de silice précipitée,
  • 0, 5 à 4 mol/l d'un agent actif de traitement, et
  • éventuellement de 0,05 à 1 mol/l d'un agent oxydant ayant un potentiel normal d'oxydoréduction E0 supérieur à 1,4 v en milieu acide fort ou de la forme réduite de cet agent oxydant.
The treatment gel of the present invention consists of a colloidal solution comprising:
  • 5 to 25% by weight, preferably 5 to 15% by weight, relative to the weight of the gel, of a mixture of fumed silica and precipitated silica,
  • 0.5 to 4 mol / l of an active treatment agent, and
  • optionally from 0.05 to 1 mol / l of an oxidizing agent having a normal redox potential E 0 greater than 1.4 v in a strong acid medium or the reduced form of this oxidizing agent.

Les concentrations sont exprimées en moles par litre de gel dans le présent texte.The concentrations are expressed in moles per liter of gel in the present text.

Des variantes et modes particuliers de réalisation du procédé de l'invention et du gel de l'invention sont tels que définis dans le jeu de revendications annexé.Particular variants and embodiments of the process of the invention and the gel of the invention are as defined in the attached set of claims.

Selon l'invention, la température de séchage du gel dans le procédé de traitement est comprise entre 20 et 30°C, et l'humidité relative entre 20% et 70%.According to the invention, the gel drying temperature in the treatment process is between 20 and 30 ° C, and the relative humidity between 20% and 70%.

On peut notamment citer les silices pyrogénées "Cab-O-Sil" M5, H5 ou EH5 (marques de commerce) commercialisées par la société CABOT et les silices pyrogénées commercialisées par la société DEGUSSA sous l'appellation AEROSIL (marques de commerce). Parmi les silices pyrogénées, on préférera la silice AEROSIL 380 (marque de commerce) d'une surface spécifique de 380 m2/g qui offre les propriétés viscosantes maximales pour une charge minérale minimale.Mention may especially be made of fumed silicas "Cab-O-Sil" M5, H5 or EH5 (trademarks) marketed by CABOT and pyrogenic silicas marketed by Degussa under the name AEROSIL (trademarks). Among the fumed silicas, AEROSIL 380 (trade mark) silica with a specific surface area of 380 m 2 / g, which offers the maximum viscosity properties for a minimum mineral filler, will be preferred.

La silice précipitée peut être obtenue par exemple humide par mélange d'une solution de silicate de soude et d'un acide. Les silices précipitées préférées sont commercialisées par DEGUSSA sous le nom de SIPERNAT 22 LS et FK 310 (marques de commerce).The precipitated silica may be obtained, for example, by mixing a solution of sodium silicate and an acid. The preferred precipitated silicas are marketed by DEGUSSA under the name SIPERNAT 22 LS and FK 310 (trademarks).

L'agent viscosant du gel de la présente invention est donc un mélange des deux types de silices précités, pyrogénée et précipitée. Le mélange des silices est de préférence à une concentration de 5 à 10% en poids du gel pour assurer un séchage du gel à température comprise entre 20°C et 30°C et humidité relative comprise entre 20 et 70 % en moyenne en 2 à 5 heures. En effet, un tel mélange influence de manière inattendue le séchage du gel et la granulométrie du résidu obtenu.The viscosifying agent of the gel of the present invention is therefore a mixture of the two types of silicas mentioned above, pyrogenated and precipitated. The mixture of the silicas is preferably at a concentration of 5 to 10% by weight of the gel to ensure drying of the gel at a temperature of between 20 ° C. and 30 ° C. and relative humidity of between 20 and 70% on average at 2 ° to 5 hours. Indeed, such a mixture unexpectedly influences the drying of the gel and the particle size of the residue obtained.

En effet, le gel sec se présente sous la forme de particules de taille contrôlée allant de 0,1 à 2 mm grâce notamment aux compositions précitées de la présente invention.Indeed, the dry gel is in the form of particles of controlled size ranging from 0.1 to 2 mm thanks in particular to the aforementioned compositions of the present invention.

Par exemple, l'ajout de 0,5 % en poids d'une silice précipitée, par exemple FK 310 (marques de commerce), à un gel à 8% de silice, par exemple AEROSIL 380 (marques de commerce), augmente la granulométrie du résidu sec et conduit à des résidus de taille millimétrique facilitant l'élimination, ou la récupération, par brossage ou aspiration.For example, the addition of 0.5% by weight of a precipitated silica, for example FK 310 (trademarks), to an 8% silica gel, for example AEROSIL 380 (trademarks), increases the granulometry of the dry residue and leads to residues of millimeter size facilitating the elimination, or the recovery, by brushing or aspiration.

L'agent actif de traitement peut être un acide ou un mélange d'acides inorganiques, de préférence choisis parmi l'acide chlorhydrique, l'acide nitrique, l'acide sulfurique et l'acide phosphorique ou un mélange de ceux-ci. L'acide est de préférence présent à une concentration de 0,1 à 7 mol/l, de préférence encore de 0,5 à 4 mol/l, pour assurer un séchage du gel à température comprise entre 20°C et 30°C et humidité relative comprise entre 20 et 70 % en moyenne en 2 à 5 heures.The active treatment agent may be an acid or a mixture of inorganic acids, preferably selected from hydrochloric acid, nitric acid, sulfuric acid and phosphoric acid or a mixture thereof. The acid is preferably present at a concentration of 0.1 to 7 mol / l, more preferably 0.5 to 4 mol / l, to ensure drying of the gel at a temperature between 20 ° C and 30 ° C and relative humidity between 20 and 70% on average in 2 to 5 hours.

Le gel de traitement selon l'invention peut également contenir en tant qu'agent actif de traitement une base de préférence une base minérale choisie de préférence parmi la soude, la potasse ou leurs mélanges.The treatment gel according to the invention may also contain, as active treatment agent, a base, preferably a mineral base preferably chosen from sodium hydroxide, potassium hydroxide or mixtures thereof.

La base est avantageusement présente à une concentration inférieure à 2 mol/l, de préférence entre 0,5 et 2mol/l, de préférence encore entre 1 et 2 mol/l pour assurer un séchage du gel à température comprise entre 20°C et 30°C et humidité relative comprise entre 20 et 70 % en moyenne en 2 à 5 heuresThe base is advantageously present at a concentration of less than 2 mol / l, preferably between 0.5 and 2 mol / l, more preferably between 1 and 2 mol / l to ensure drying of the gel at a temperature of between 20 ° C. and 30 ° C and relative humidity between 20 and 70% on average in 2 to 5 hours

Enfin, le gel de l'invention peut contenir un agent oxydant, par exemple à une concentration de 0,5 à 1 mol/l, qui présente un potentiel normal d'oxydo-réduction supérieur a 1400 mV en milieu acide fort, c'est-à-dire un pouvoir oxydant supérieur à celui du permanganate. A titré d'exemple, de tels agents oxydants peuvent être le Ce(IV) le Co(III) et l'Ag(II).Finally, the gel of the invention may contain an oxidizing agent, for example at a concentration of 0.5 to 1 mol / l, which has a normal oxidation-reduction potential greater than 1400 mV in a strong acid medium, that is to say, an oxidizing power greater than that of permanganate. For example, such oxidizing agents may be Ce (IV) Co (III) and Ag (II).

Les agents oxydants, parmi lesquels le cérium IV est préféré, sont généralement associés à un acide minéral, comme de préférence l'acide nitrique à une concentration modérée inférieure à 2 mol/l et autorisant un séchage rapide du gel. Le cérium est généralement introduit sous forme de nitrate de cérium (IV) électrogénéré Ce(NO3)4 ou de l'hexanitrato cérate de diammonium (NH4)2Ce(NO3)5.The oxidizing agents, among which cerium IV is preferred, are generally associated with a mineral acid, such as nitric acid at a moderate concentration of less than 2 mol / l, and allowing rapid drying of the gel. Cerium is generally introduced in the form of electrogenerated cerium (IV) nitrate Ce (NO 3 ) 4 or hexanitrate cerium (NH 4 ) 2 Ce (NO 3 ) 5 .

Ainsi un exemple typique de gel de décontamination oxydant selon l'invention est constitué d'une solution colloïdale comprenant 0,1 à 0,5 mol/l de Ce(NO3)4 ou (NH4)2Ce(NO3)6, de 0,5 à 2 mol/l d'acide nitrique et de 5 à 15 % en poids de silice.Thus, a typical example of an oxidizing decontamination gel according to the invention consists of a colloidal solution comprising 0.1 to 0.5 mol / l of This (NO 3 ) 4 or (NH 4 ) 2 Ce (NO 3 ) 6 , from 0.5 to 2 mol / l of nitric acid and from 5 to 15% by weight of silica.

Les gels de l'invention peuvent aisément être préparés, à la température ambiante, en ajoutant à une solution aqueuse l'agent gélifiant minéral constitué du mélange de silices qui présente de préférence une surface spécifique élevée, par exemple supérieure à 100 m2/g. Une viscosité au moins égale à 350 mPa.s et un temps de reprise de la viscosité inférieur à une seconde sont préférés pour que le gel puisse être pulvérisé, à distance ou non, sur la surface à traiter sans couler.The gels of the invention can easily be prepared at room temperature by adding to an aqueous solution the mineral gelling agent consisting of the silica mixture which preferably has a high specific surface area, for example greater than 100 m 2 / g. . A viscosity of at least 350 mPa.s and a viscosity recovery time of less than one second are preferred so that the gel can be sprayed, remotely or not, on the surface to be treated without pouring.

L'objectif atteint par la présente invention consiste donc aussi à fournir des gels à durée d'action contrôlée par un temps de séchage rapide, suffisant pour garantir le traitement de la surface, le plus souvent compris entre 2 et 5 heures, et même entre 2 et 3 heures., à température comprise entre 20°C et 30°C et humidité relative moyenne comprise entre 20 et 70 %.The objective of the present invention is therefore also to provide gels with controlled duration of action by a fast drying time, sufficient to ensure the treatment of the surface, usually between 2 and 5 hours, and even between 2 and 3 hours at a temperature between 20 ° C and 30 ° C and average relative humidity between 20 and 70%.

En outre, du fait que les gels selon l'invention comprennent un mélange d'agents viscosants et un agent actif de décontamination aux concentrations précitées, le séchage du gel conduit à un résidu sec présentant une aptitude à se détacher facilement du support. Ainsi, aucun rinçage à l'eau n'est nécessaire et le procédé ne génère ainsi aucun effluent secondaire.In addition, since the gels according to the invention comprise a mixture of viscosifying agents and an active decontamination agent at the above concentrations, the drying of the gel leads to a dry residue having an ability to easily detach from the support. Thus, no rinsing with water is necessary and the process thus generates no secondary effluent.

Les gels de la présente invention peuvent être décrits de manière générale comme des solutions colloïdales comprenant un mélange de silices et un agent actif de traitement, par exemple un acide, une base, un agent oxydant, un agent réducteur ou un mélange de ceux-ci, qui est choisi notamment en fonction de la nature du traitement et de la surface à traiter.The gels of the present invention can be generally described as colloidal solutions comprising a mixture of silicas and an active treatment agent, for example an acid, a base, an oxidizing agent, a reducing agent or a mixture thereof, which is chosen in particular according to the nature of the treatment and the surface to be treated.

Ainsi pour un traitement consistant en l'élimination d'une contamination non fixée, sous la forme de graisses, sur des surfaces en acier inox et ferritiques, un gel alcalin présentant des propriétés dégraissantes peut être utilisé.Thus for a treatment consisting in the removal of an unfixed contamination, in the form of greases, on stainless steel and ferritic surfaces, an alkaline gel having degreasing properties can be used.

L'élimination d'une contamination fixée à chaud et à froid sur une surface en acier inox peut se faire au moyen d'un gel oxydant. La dissolution de couches d'oxydes peut se faire au moyen d'un gel réducteur qui sera utilisé de préférence en complément du gel oxydant et de manière alternée.The removal of a hot and cold-fixed contamination on a stainless steel surface can be done by means of an oxidizing gel. The dissolution of oxide layers can be done by means of a reducing gel which will preferably be used in addition to the oxidizing gel and alternately.

Enfin une contamination fixée à froid sur un acier ferritique peut être éliminée par exemple au moyen d'un gel acide.Finally a cold-fixed contamination on a ferritic steel can be removed for example by means of an acid gel.

Le gel peut être appliqué sur la surface à traiter par des procédés classiques tels que par pulvérisation au pistolet ou au moyen d'un pinceau, par exemple d'un pinceau à décontaminer.The gel may be applied to the surface to be treated by conventional methods such as spraying with a spray gun or with a brush, for example a brush to be decontaminated.

Pour l'application par pulvérisation du gel sur la surface à traiter, la solution colloïdale visqueuse peut par exemple être véhiculée par l'intermédiaire d'une pompe basse pression (<7 bars) et l'éclatement du jet de gel sur la surface peut être obtenu avec une buse à et plat ou à jet rond. Le temps de reprise de la viscosité suffisamment court permet au gel pulvérisé d'adhérer à la paroi.For the spray application of the gel on the surface to be treated, the viscous colloidal solution may for example be conveyed via a low pressure pump (<7 bars) and the bursting of the gel jet on the surface may be obtained with a flat or round nozzle. The sufficiently short viscosity recovery time allows the sprayed gel to adhere to the wall.

Les quantités de gel déposées sur la surface à traiter sont généralement de 100 à 2000 g/m2, de préférence 100 à 1000 g/m2, de préférence encore 300 à 700 g/m2. Elles influencent la durée de séchage du,gel.The amounts of gel deposited on the surface to be treated are generally 100 to 2000 g / m 2 , preferably 100 to 1000 g / m 2 , more preferably 300 to 700 g / m 2 . They influence the drying time of the gel.

La durée de séchage du gel de la présente invention dépend principalement de sa composition dans les fourchettes de concentration définies ci-dessus. Elle est généralement comprise entre 2 et 5 heures, plus précisément entre 2 et 3 heures, à température comprise entre 20°C et 30°C et humidité relative moyenne comprise entre 20 et 70 %.The drying time of the gel of the present invention depends mainly on its composition within the concentration ranges defined above. It is generally between 2 and 5 hours, more precisely between 2 and 3 hours, at a temperature of between 20 ° C. and 30 ° C. and a mean relative humidity of between 20 and 70%.

Le résidu sec obtenu après séchage peut être éliminé facilement, par exemple par brossage et/ou aspiration, mais aussi par jet de gaz, par exemple d'air comprimé.The dry residue obtained after drying can be easily removed, for example by brushing and / or suction, but also by gas jet, for example compressed air.

Il est évident que le traitement de la surface pourra être renouvelé chaque fois avec le même gel ou avec des gels de nature différente lors des différentes étapes successives, chacune de ces étapes comprenant l'application du gel, le maintien du gel sur la surface pendant le traitement de la surface et son séchage, ainsi que l'élimination du résidu sec obtenu.It is obvious that the treatment of the surface can be renewed each time with the same gel or with gels of different nature during the different successive stages, each of these steps including the application of the gel, the maintenance of the gel on the surface during the treatment of the surface and its drying, as well as the removal of the dry residue obtained.

La présente invention s'applique de manière générale au traitement, par exemple de décontamination, de surfaces métalliques, importantes ou non, qui ne sont pas nécessairement horizontales, mais qui peuvent être inclinées ou mêmes verticales.The present invention is generally applicable to the treatment, for example of decontamination, of metal surfaces, important or not, which are not necessarily horizontal, but which can be inclined or even vertical.

Par traitement on entend tout traitement de surface destiné à nettoyer, décontaminer ou décaper ladite surface. Il peut s'agir par exemple d'un traitement de décontamination radioactive ou organique (par exemple élimination de microorganismes, de parasites etc...), d'un traitement de décapage destiné à éliminer des oxydes ou d'un traitement de dégraissage d'une surface.Treatment means any surface treatment for cleaning, decontaminate or etch said surface. It may be for example a radioactive or organic decontamination treatment (eg removal of microorganisms, parasites etc ...), a pickling treatment for removing oxides or a degreasing treatment of a surface.

La présente invention peut être utilisée pour traiter toutes sortes de surfaces telles que des surfaces métalliques, des surfaces en matières plastiques, des surfaces de matériaux vitreux etc...The present invention can be used to treat all kinds of surfaces such as metal surfaces, plastic surfaces, vitreous material surfaces, etc.

L'homme du métier saura adapter les compositions précitées des gels de la présente invention suivant la surface à traiter et le traitement à effectuer.Those skilled in the art will be able to adapt the aforementioned compositions of the gels of the present invention according to the surface to be treated and the treatment to be carried out.

La présente invention peut avantageusement être utilisée par exemple dans le domaine du nucléaire pour décontaminer des cuves, des gaines de ventilation, des piscines d'entreposage, des boîtes à gants, etc. Elle peut être utilisée aussi bien dans le cadre de la maintenance périodique d'installations existantes, que de l'assainissement d'installations.The present invention may advantageously be used for example in the nuclear field for decontaminating tanks, ventilation ducts, storage pools, glove boxes, etc. It can be used both for periodic maintenance of existing installations and for the remediation of installations.

En effet, elle permet de limiter la quantité d'effluent produite lors du traitement des éléments précités.Indeed, it limits the amount of effluent produced during the treatment of the aforementioned elements.

Elle trouve également une application dans le traitement d'installations dans lesquelles l'introduction de liquide est proscrite. Un exemple d'une telle application est la décontamination de gaines de ventilation d'installations nucléaires.It is also applicable in the treatment of installations in which the introduction of liquid is prohibited. An example of such an application is the decontamination of ventilation ducts of nuclear installations.

La présente invention se rapporte donc également à un procédé de décontamination d'une installation.The present invention thus also relates to a method for decontaminating an installation.

Selon l'invention, le procédé de décontamination peut comprendre un dépoussiérage de l'installation à traiter, suivi d'un traitement de l'installation au moyen d'un procédé de traitement selon la présente invention.According to the invention, the decontamination process can comprise a dedusting of the installation to be treated, followed by a treatment of the installation at by means of a treatment method according to the present invention.

Le dépoussiérage de l'installation à traiter peut être réalisé par exemple par brossage, soufflage ou aspiration des poussières afin d'enlever la contamination solide non fixée. Ce prétraitement peut être effectué par exemple sur les gaines en acier inoxydable de ventilation d'installations nucléaires qui contiennent des quantités importantes de poussières.The dedusting of the installation to be treated can be achieved for example by brushing, blowing or dust extraction to remove solid unbound contamination. This pretreatment can be carried out for example on the stainless steel ventilation ducts of nuclear installations which contain large quantities of dust.

Le procédé de traitement de la présente invention peut ensuite être utilisé en appliquant une ou plusieurs passes de gel de l'invention pour éliminer la contamination fixée au niveau des parois internes des gaines. Les gels sèchent totalement après avoir agi sur la surface et se détachent facilement de la paroi par aspiration.The treatment method of the present invention can then be used by applying one or more gel passes of the invention to remove the contamination attached to the inner walls of the sheaths. The gels dry completely after having acted on the surface and are easily detached from the wall by suction.

D'autres caractéristiques et avantages de l'invention apparaîtront encore à la lecture des exemples suivants, en référence aux dessins annexés, donnés bien entendu à titre illustratif et non limitatif.Other features and advantages of the invention will become apparent on reading the following examples, with reference to the accompanying drawings, given of course by way of illustration and not limitation.

BREVE DESCRIPTION DES FIGURESBRIEF DESCRIPTION OF THE FIGURES

  • La figure 1 représente des abaques de séchage d'un gel selon la présente invention à 30°C en fonction de l'humidité relative, ce gel ayant une formulation Aerosil 380 (marque de commerce) 8% + HNO3 7 M.FIG. 1 represents drying slabs of a gel according to the present invention at 30 ° C. as a function of the relative humidity, this gel having an Aerosil 380 (trademark) 8% + HNO 3 7 M formulation.
  • La figure 2 représente des abaques de séchage d'un gel de la présente invention à 25°C en fonction de l'humidité relative, ce gel ayant une formulation Aerosil 380 (marque de commerce) 8 % + HNO3 7 M (sur la courbe -x- : T : 25°C - H2 : 42% Si038 seule).FIG. 2 shows drying plots of a gel of the present invention at 25 ° C. as a function of relative humidity, this gel having a formulation Aerosil 380 (trademark) 8% HNO 3 + 7 M (on the -x- curve: T: 25 ° C - H 2: 42% only Si038).
  • La figure 3 représente des abaques de séchage d'un gel de la présente invention à 20°C en fonction de l'humidité relative, ce gel ayant une formulation Aerosil 380(marque de commerce) 8% + HNO3 7 M.FIG. 3 shows gel drying charts of the present invention at 20 ° C. as a function of relative humidity, this gel having an Aerosil 380 (trademark) 8% + HNO 3 7 M formulation.
  • La figure 4 représente des abaques de séchage d'un gel de la présente invention à 20°C et 40% d'humidité relative en fonction de la quantité de gel appliquée sur une surface, ce gel ayant une formulation Aerosil 380(marque de commerce) 8% + HNO3 7 M.FIG. 4 shows gel drying plots of the present invention at 20 ° C. and 40% relative humidity depending on the amount of gel applied to a surface, this gel having an Aerosil 380 formulation. ) 8% + HNO 3 7 M.
  • La figure 5 est un graphique représentant l'influence du taux d'humidité sur la cinétique de séchage à différentes températures de séchage d'un gel selon l'invention, ce gel ayant une formulation Aerosil 380(marque de commerce) 8% + HNO3 7 M.FIG. 5 is a graph showing the influence of the moisture content on the drying kinetics at different drying temperatures of a gel according to the invention, this gel having a formulation Aerosil 380 (trademark) 8% + HNO 3 7 M.
  • La figure 6 est un graphique représentant l'influence de la température sur la cinétique de séchage d'un gel selon l'invention à 42% d'humidité relative, ce gel ayant une formulation Aerosil 380(marque de commerce) 8% + HNO3 7 M.FIG. 6 is a graph showing the influence of temperature on the drying kinetics of a gel according to the invention at 42% relative humidity, this gel having a formulation Aerosil 380 (trademark) 8% + HNO 3 7 M.
  • La figure 7 présente quatre photographies montrant des résidus secs de gels obtenus avec le mélange Aérosil 380 (marque de commerce) à 8% et FK310 (marque de commerce) 0,5% d'une part et le mélange Aérosil 380 (marque de commerce) 8% et FK310 (marque de commerce) 1% d'autre part pour deux modes de séchage.Figure 7 presents four photographs showing dry gel residues obtained with Aerosil 380 (trademark) 8% and FK310 (trademark) 0.5% and Aerosil 380 (trademark). ) 8% and FK310 (trademark) 1% secondly for two drying modes.
  • la figure 8 est un graphique représentant la perte de masse de deux gels d'alumine à 2,5 et 5 mol/l de soude en fonction du temps (M = masse et t = temps).Figure 8 is a graph showing the mass loss of two gels of alumina at 2.5 and 5 mol / l of sodium as a function of time (M = mass and t = time).

Sur ces figures, Te représente le taux d'évaporation en pourcentage de la quantité initiale de solvant, ts : le temps de séchage en minutes, T : les températures de séchage pour chaque courbe en °C, et Hr le taux d'humidité relative lors des différents essais exprimé en pourcentage.In these figures, Te represents the evaporation rate as a percentage of the initial quantity of solvent, ts : the drying time in minutes, T : the drying temperatures for each curve in ° C, and Hr the relative humidity level during the different tests expressed as a percentage.

EXEMPLESEXAMPLES Exemple 1 (non revendiqué) Example 1 (not claimed)

Les propriétés de séchage d'un gel à base de silice AEROSIL 380, silice pyrogénée à surface spécifique élevée de 380 m2/g sont étudiées dans cet exemple.The drying properties of a silica-based gel AEROSIL 380, fumed silica with a high specific surface area of 380 m 2 / g are studied in this example.

Des essais préliminaires réalisés par les inventeurs ont permis de montrer qu'en milieu nitrique concentré 7 M, l'utilisation d'une formulation à base de silice pyrogénée, par exemple de type AEROSIL 380 (marque de commerce), à une concentration comprise entre 8 et 10% en poids permet d'obtenir des résidus secs qui se détachent facilement au bout de quelques heures (entre 2 et 5 heures environ). Ainsi, les temps de contact sont suffisants pour traiter une surface. Une teneur de l'ordre de 8% en masse de silice a donc été retenue par les inventeurs.Preliminary tests carried out by the inventors have made it possible to show that in a 7M concentrated nitric medium, the use of a formulation based on fumed silica, for example of the AEROSIL 380 (trademark) type, at a concentration of between 8 and 10% by weight makes it possible to obtain dry residues which are easily detached after a few hours (between about 2 and 5 hours). Thus, the contact times are sufficient to treat a surface. A content of the order of 8% by weight of silica was therefore retained by the inventors.

La quantité de gel déposée sur la surface n'a eu qu'une légère influence sur les caractéristiques de séchage et plus particulièrement sur l'aptitude au détachement. Différentes quantités de gel allant de 0,1 à 2 Kg de gel par m2 ont été déposées sur des surfaces. Les quantités de 0,3 kg.m-2 à 0,7 kg.m-2 environ sont préférées.The amount of gel deposited on the surface had only a slight influence on the drying characteristics and more particularly on the detachability. Different amounts of gel ranging from 0.1 to 2 kg of gel per m 2 were deposited on surfaces. The amounts of about 0.3 kg.m -2 to about 0.7 kg.m -2 are preferred.

Les conditions de séchage constituent les paramètres les plus importants dans le procédé de la présente invention. Parmi eux, on trouve la température de séchage et le taux d'humidité de l'air de séchage. L'existence d'un courant convectif est également importante. L'influence de ces paramètres a été appréciée quantitativement en traçant des abaques de séchage.The drying conditions are the most important parameters in the process of the present invention. Among them is the drying temperature and the moisture content of the drying air. The existence of a convective current is also important. The influence of these parameters was assessed quantitatively by plotting drying charts.

Le domaine de température qui est retenu est 20°C à 30°C et le domaine d'humidité relative de l'air de séchage 20% à 70%, l'humidité relative étant définie comme le rapport de la pression de vapeur d'eau à une température donnée à la pression de vapeur saturante de l'eau à la même température.The temperature range which is retained is 20 ° C to 30 ° C and the relative humidity range of drying air 20% to 70%, the relative humidity being defined as the ratio of the vapor pressure of water at a given temperature at the saturation vapor pressure of the water at the same temperature.

Des pièces en acier inoxydable 304 L neuves sont enduites de gel. La quantité de gel déposée est de 0,5 kg.m-2 (±5%) pour les essais suivants lorsque ceci n'est pas précisé.New 304 L stainless steel parts are gel coated. The amount of gel deposited is 0.5 kg.m -2 (± 5%) for the following tests when this is not specified.

Les silices sont pré-mélangées en bécher cylindrique à 800 tours.min-1 à l'aide d'un agitateur à hélice afin d'assurer un mélange intime des silices. Lors de la préparation, le gel est agité à 500 tours.min-1 par le même système d'agitation.The silicas are pre-mixed in a cylindrical beaker tours.min 800 -1 using a propeller stirrer to ensure intimate mixing of the silica. When preparing the gel was stirred at 500 tours.min -1 by the same stirring system.

Les échantillons revêtus sont placés dans une enceinte climatique à température et humidité contrôlées. L'enceinte climatique est de marque de commerce KBF et de volume 115 litres. La régulation d'humidité est assurée par injection de vapeur générée par le passage d'un courant électrique dans l'humidificateur. La vitesse du courant convectif à la surface des échantillons peut être considérée comme identique pour tous les cas et de très faible intensité. La masse de l'enduction au cours du temps est suivie pour chaque couple température/humidité fixé.Coated samples are placed in a climatic chamber at controlled temperature and humidity. The climate chamber is a KBF trademark with a volume of 115 liters. Humidity control is provided by steam injection generated by the passage of an electric current through humidifier. The speed of the convective current at the surface of the samples can be considered as identical for all the cases and of very low intensity. The mass of the coating over time is monitored for each set temperature / humidity pair.

1°) INFLUENCE DE LA TEMPERATURE1 °) INFLUENCE OF THE TEMPERATURE

Pour trois températures 30°C, 25°C et 20°C les abaques représentés respectivement sur les figures 1 à 3 ont été tracées pour plusieurs valeurs de l'humidité relative.For three temperatures 30 ° C., 25 ° C. and 20 ° C., the graphs shown respectively in FIGS. 1 to 3 have been plotted for several values of the relative humidity.

Les courbes correspondant aux abaques à 30°C sont présentées sur la figure 1.The curves corresponding to the charts at 30 ° C. are presented in FIG.

Les courbes obtenues sur cette figure présentent une partie linéaire correspondant à la phase à vitesse de séchage constante. La vitesse de séchage est d'autant plus lente que l'humidité est élevée ce qui est cohérent. Pour les faibles humidités (20% et 35%) on note l'apparition d'un palier à partir de 200 minutes environ. Ce palier correspond à 100% de solvant évaporé ce qui indique que la phase de séchage à vitesse décroissante est quasi inexistante. On en déduit que le gel est totalement sec au bout de trois heures environ dès que l'humidité est inférieure à 35%. En revanche, pour les valeurs supérieures le palier n'est pas atteint après le temps d'expérience. Il peut être obtenu par extrapolation de la phase initiale de séchage à vitesse constante. Dans ces conditions, on constate qu'en l'absence de courant convectif, une humidité de 50% conduit à un temps de séchage extrapolé de 8 heures environ ce qui reste compatible avec une opération de décontamination. Une humidité relative supérieure à 70% conduit dans ce cas à des temps de séchage excessifs.The curves obtained in this figure have a linear part corresponding to the constant drying rate phase. The speed of drying is even slower than humidity is high which is consistent. For low humidities (20% and 35%) there is the appearance of a plateau from about 200 minutes. This level corresponds to 100% evaporated solvent, which indicates that the drying phase at decreasing speed is almost non-existent. It is deduced that the gel is completely dry after about three hours when the humidity is less than 35%. On the other hand, for the higher values the step is not reached after the experiment time. It can be obtained by extrapolation of the initial phase of drying at constant speed. Under these conditions, it is found that in the absence of convective current, a humidity of 50% leads to an extrapolated drying time about 8 hours which is compatible with a decontamination operation. Relative humidity above 70% in this case leads to excessive drying times.

Les courbes correspondant aux abaques à 25°C sont présentées sur la figure 2. L'essai à 70% d'humidité relative a été supprimé compte tenu des durées de séchage plus longues observées à 30°C.The curves corresponding to the charts at 25 ° C. are shown in FIG. 2. The test at 70% relative humidity was suppressed taking into account the longer drying times observed at 30 ° C.

Les courbes obtenues ont la même allure qu'à 30°C. Toutefois, les temps de séchage sont allongés. Le séchage total est obtenu à 35% d'humidité en un temps de l'ordre de 5 heures. Compte tenu de l'essai réalisé à 30°C il est déterminé par extrapolation qu'avec une humidité relative de 20% le temps de séchage total pour cette valeur à 25°C est compris entre 3 heures et 5 heures. A 50% d'humidité le temps de séchage total extrapolé est de 9 heures ce qui reste acceptable dans un procédé de traitement d'une surface.The curves obtained have the same pace as at 30 ° C. However, the drying times are lengthened. The total drying is obtained at 35% humidity in a time of the order of 5 hours. Considering the test carried out at 30 ° C it is determined by extrapolation that with a relative humidity of 20% the total drying time for this value at 25 ° C is between 3 hours and 5 hours. At 50% humidity the extrapolated total drying time is 9 hours which remains acceptable in a surface treatment process.

Grâce aux essais suivants, il a été possible de déduire une valeur pratique pour une atmosphère de cellule blindée. Un abaque de séchage a été tracé dans une cellule blindée de la marque de commerce DEMETER, la température de l'air de la cellule était de 22°C. Les courbes correspondant à cet essai ainsi que d'autres réalisées à 20°C dans l'enceinte climatique sont présentées sur la figure 3 annexée. Sur cette figure, la référence « Cell » représente la cellule DEMETER (marque de commerce).Thanks to the following tests, it has been possible to deduce a practical value for an armored cell atmosphere. A drying chart was plotted in an armored cell of the trademark DEMETER, the air temperature of the cell was 22 ° C. The curves corresponding to this test as well as others produced at 20 ° C. in the climatic chamber are shown in the appended FIG. In this figure, the reference "Cell" represents the DEMETER cell (trademark).

L'essai réalisé dans la cellule DEMETER se superpose avec l'essai réalisé à 42% d'humidité relative dans l'enceinte climatique. Ceci permet de dégager un couple de valeurs représentatives de l'atmosphère d'une cellule blindée soit 20°C et 42% d'humidité relative environ. Cette analogie ne prend pas en compte un éventuel écart de la convection entre l'enceinte climatique et la cellule blindée.The test carried out in the DEMETER cell is superimposed with the test carried out at 42% relative humidity in the climatic chamber. This allows to derive a pair of values representative of the atmosphere of an armored cell, ie approximately 20 ° C. and 42% relative humidity. This analogy does not take into account a possible deviation of the convection between the climatic chamber and the armored cell.

En ce qui concerne le temps de séchage total à 20°C, compte tenu des résultats expérimentaux, il a été estimé à 7 heures environ à 35% d'humidité et à 8 heures environ à 42% d'humidité.With regard to the total drying time at 20 ° C, considering the experimental results, it was estimated at about 7 hours at 35% humidity and at about 8 hours at 42% humidity.

2°) INFLUENCE DE LA QUANTITE DE GEL APPLIQUEE2 °) INFLUENCE OF THE QUANTITY OF APPLIED GEL

La figure 4 annexée rassemble des courbes réalisées pour trois quantités de gel déposées à 20°C et à 42% d'humidité relative.The attached FIG. 4 gathers curves made for three quantities of gel deposited at 20 ° C. and at 42% relative humidity.

Cette figure montre que la cinétique de séchage est peu affectée entre 0,33 kg.m-2 et 0,42 kg.m-2 de gel déposé. Une différence plus nette est visible pour 0,5 kg.m-2. Dans ces conditions il apparaît donc préférable de viser des taux d'application relativement faibles, de l'ordre de 0,3 kg.m-2.This figure shows that the kinetics of drying is little affected between 0.33 kg.m -2 and 0.42 kg.m -2 of deposited gel. A clearer difference is visible for 0.5 kg.m- 2 . Under these conditions it therefore seems preferable to aim for relatively low application rates of the order of 0.3 kg.m -2 .

3°) INFLUENCE DE L'HUMIDITE SUR LA CINETIQUE DE SECHAGE3 °) INFLUENCE OF MOISTURE ON KINETIC DRYING

Afin d'évaluer l'incidence de l'humidité, des courbes ont été tracées à partir de points caractéristiques des phases de séchage à vitesse constante du gel observées lors des essais précédents réalisés à température fixée. Ces courbes sont présentées sur la figure 5 annexée. Sur cette figure, « L » représente un linéaire de séchage à 30°C pendant 120 minutes tracé à partir des valeurs moyennes de la courbe correspondante. Ce linéaire a pour équation y = -1,6039x + 110,27, avec x l'humidité relative en %, et y le taux d'évaporation (% de la quantité initiale de solvant).In order to evaluate the incidence of humidity, curves were drawn from characteristic points of the constant speed drying phases of the gel observed during the previous tests carried out at fixed temperature. These curves are presented in the appended FIG. In this figure, "L" represents a linear drying at 30 ° C for 120 minutes plotted from the average values of the corresponding curve. This linear has for equation y = -1.6039x + 110.27, with x the relative humidity in%, and y the rate of evaporation (% of the initial quantity of solvent).

Les temps caractéristiques ayant été choisis dans le domaine de séchage à vitesse constante, pour une température donnée, les taux d'humidité portés en ordonnée varient proportionnellement à la vitesse de séchage. En revanche la comparaison directe d'une température à l'autre n'est pas possible car les temps caractéristiques retenus ne sont pas identiques pour toutes les températures.Since the characteristic times have been chosen in the constant-speed drying range, for a given temperature, the humidity levels plotted on the ordinate vary in proportion to the drying speed. On the other hand, the direct comparison of one temperature with the other is not possible because the characteristic times retained are not identical for all the temperatures.

Cette figure montre que la vitesse de séchage diminue de manière linéaire lorsque le taux d'humidité relative augmente pour toutes les températures, dans le domaine expérimental. L'influence du taux d'humidité a tendance à augmenter légèrement lorsque la température diminue ce qui est cohérent.This figure shows that the drying rate decreases linearly as the relative humidity increases for all temperatures, in the experimental field. The influence of the moisture content tends to increase slightly when the temperature decreases which is consistent.

L'augmentation de l'humidité de 10% se traduit par une diminution de la vitesse de séchage de 16 %. Ceci montre l'importance de bien connaître les conditions de séchage lors de l'application du gel dans le procédé de la présente invention.Increasing the humidity by 10% results in a decrease in drying speed of 16%. This demonstrates the importance of knowing the drying conditions when applying the gel in the process of the present invention.

3°) INFLUENCE DE LA TEMPERATURE SUR LA CINETIQUE DE SECHAGE3 °) INFLUENCE OF THE TEMPERATURE ON THE KINETIC DRYING

Pour des essais réalisés à 42% d'humidité relative, une comparaison des cinétiques aux différentes températures est effectuée. Les résultats sont portés sur la figure 6.For tests carried out at 42% relative humidity, a comparison of the kinetics at different temperatures is carried out. The results are shown in FIG.

Comme précédemment, on peut évaluer que l'augmentation de la température de 10% conduit à une augmentation de la vitesse de séchage de 13% environ. On constate donc les effets contraires de l'augmentation de l'humidité et de la température.As before, it can be estimated that the increase in temperature of 10% leads to an increase in the drying rate of about 13%. The opposite effects of increased humidity and temperature are thus noted.

Les abaques de séchage établis dans cet exemple permettent de prévoir les temps de séchage nécessaires lors d'une application du procédé de la présente invention pourvu que la température de l'air de la gaine et son humidité relative soient connues.The drying charts set forth in this example allow the drying times required during an application of the process of the present invention to be provided provided that the air temperature of the sheath and its relative humidity are known.

Le domaine représentatif de l'atmosphère d'une cellule blindée a été estimé centré autour des valeurs suivantes : température : 20°C et humidité relative : 40%. Ces valeurs ont été obtenues par analogie en effectuant un essai de séchage dans la cellule DEMETER (marque de commerce).The area representative of the atmosphere of an armored cell was estimated centered around the following values: temperature: 20 ° C and relative humidity: 40%. These values were obtained by analogy by carrying out a drying test in the DEMETER (trademark) cell.

En ce qui concerne la compatibilité des temps de séchage avec une opération de décontamination, les abaques montrent une bonne compatibilité dès que la température est supérieure à 20°C et l'humidité est inférieure à 40% environ. Pour des températures plus basses ou des humidités plus élevées, il peut être nécessaire de mettre en place un régime convectif dans la gaine ce qui pourra être réalisé avec une marche à demi-régime.As regards the compatibility of the drying times with a decontamination operation, the charts show good compatibility as soon as the temperature is above 20 ° C and the humidity is below about 40%. For lower temperatures or higher humidities, it may be necessary to implement a convective regime in the sheath which can be achieved with a half-speed operation.

Exemple 2Example 2

Dans cet exemple, les propriétés de séchage d'un gel à base d'un mélange de silices constitué de 8% en poids d'AEROSIL 380 (marque de commerce), qui est une silice pyrogénée à surface spécifique élevée de 380 m2/g, et de 0,5% à 1% en poids de silice précipitée FK 310 (marque de commerce).In this example, the drying properties of a silica-based gel consisting of 8% by weight of AEROSIL 380 (trademark), which is a fumed silica with a high specific surface area of 380 m 2 / g, and from 0.5% to 1% by weight of precipitated silica FK 310 (trademark).

La taille des résidus obtenus après séchage dans le cas du mélange Aérosil 380 (marque de commerce) et FK310 a été comparée à la taille des résidus recueillis dans le cas de la silice Aérosil 380 (marque de commerce) seule.The size of the residues obtained after drying in the case of the mixture Aerosil 380 (trademark) and FK310 was compared to the size of the residues collected in the case of Aerosil 380 silica (trademark) alone.

Sur la figure 7 annexée, des photographies des résidus secs obtenus avec le mélange Aérosil 380 (marque de commerce) à 8% et FK310 (marque de commerce) à 0,5%, référencées « A », d'une part et le mélange Aérosil 380 (marque de commerce) 8% et FK310 (marque de commerce) à 1%, référencées « B », d'autre part sont présentées pour deux modes de séchage, l'un à 30°C et l'autre à température ambiante (25°C).In the attached FIG. 7, photographs of the dry residues obtained with the mixture Aerosil 380 (trademark) at 8% and FK310 (trademark) at 0.5%, referenced "A", on the one hand and the mixture Aerosil 380 (trademark) 8% and FK310 (trademark) 1%, referenced "B", on the other hand are presented for two modes of drying, one at 30 ° C and the other at temperature ambient temperature (25 ° C).

Ces résultats montrent que la taille des résidus secs dépend peu des conditions de séchage ce qui constitue un avantage. En ce qui concerne la taille des résidus, on observe dans tous les cas qu'elle est très supérieure à celle obtenue dans le cas de la silice Aérosil 380 seule. Ici, la taille des résidus les plus grands est supérieure au millimètre contre 600.10-6 m dans le cas de la silice Aérosil 380 (marque de commerce) seule. La proportion des résidus de grande dimension est beaucoup plus importante. Parallèlement, il y a beaucoup moins de résidus de très faibles dimensions susceptibles de ne pas être ré-entrainés lors de l'élimination des résidus secs. Sans faire d'analyse quantitative précise sur les distributions granulométriques on peut avancer un ordre de grandeur de 2 à 3 pour l'augmentation de la taille moyenne des résidus secs ce qui est spectaculaire compte tenu de la faible quantité de silice ajoutée. Le résultat est observé dès l'ajout de 0,5% de silice FK 310 (marque de commerce).These results show that the size of the dry residues depends little on the drying conditions which is an advantage. Regarding the size of the residues, it is observed in all cases that it is much higher than that obtained in the case of Aerosil 380 silica alone. Here, the size of the largest residues is greater than one millimeter against 600.10 -6 m in the case of silica Aerosil 380 (trademark) alone. The proportion of large tailings is much larger. At the same time, there are far fewer residues of very small dimensions that may not be re-trained during the disposal of dry residues. Without making a precise quantitative analysis on particle size distributions, we can advance an order of magnitude of 2 to 3 for the increase of the average size of dry residues which is spectacular considering the small amount of silica added. The result is observed when adding 0.5% silica FK 310 (trademark).

Ce résultat est très important car il montre que la présente invention fournit un gel possédant des caractéristiques voisines de celles, d'un gel de décontamination classique tant qu'il n'est pas sec en terme de temps de contact et de composition. En revanche, lorsque le gel est sec, ses résidus sont de taille contrôlée de manière relativement indépendante des caractéristiques de séchage grâce à l'ajout de silice précipitée Les avantages sont notamment l'absence de résidu pulvérulent, les tailles obtenues étant de l'ordre de 0,1 à 3 mm, facilitant l'aptitude au décollement du résidu de la surface, et la récupération par brossage ou aspiration.This result is very important because it shows that the present invention provides a gel having characteristics similar to those of a conventional decontamination gel as long as it is not dry in terms of contact time and composition. On the other hand, when the gel is dry, its residues are of controlled size relatively independently of the drying characteristics thanks to the addition of precipitated silica. The advantages are in particular the absence of pulverulent residue, the sizes obtained being of the order 0.1 to 3 mm, facilitating the debondability of the surface residue, and recovery by brushing or aspiration.

Exemple 3 (non revendiqué) Example 3 (not claimed)

Pour décontaminer de l'aluminium, des gels à base de silice AEROSIL 380 (marque de commerce) à 8% en poids et d'un mélange d'acide nitrique et d'acide phosphorique ont été préparés. La concentration de chacun des deux acides est de préférence inférieure à 2 mol/l. Au-delà, le gel ne sèche pas à une température de 25°C et une humidité relative de 40%. Pour une concentration de chacun des deux acides comprise entre 1 et 2 M, les temps de séchage observés à une température de 25°C et une humidité relative de 40% varient entre 2 et 4 heures.To decontaminate aluminum, 8% by weight AEROSIL 380 (trade mark) silica gels and a mixture of nitric acid and phosphoric acid were prepared. The concentration of each of the two acids is preferably less than 2 mol / l. Beyond this, the gel does not dry at a temperature of 25 ° C and a relative humidity of 40%. For a concentration of each of the two acids of between 1 and 2 M, the drying times observed at a temperature of 25 ° C and a relative humidity of 40% vary between 2 and 4 hours.

Un gel (HNO3 1M /H3PO4 1M) a été notamment préparé et testé en terme de décontamination sur des brides en aluminium provenant d'un réseau de transfert pneumatique d'une usine de retraitement de déchets nucléaires. Des facteurs de décontamination de l'ordre de 14 (Cs 137, Eu 154) ont été obtenus après une seule passe de gel (Cs 137: de 1300 Bq/cm2 à 110 Bq/cm2) et l'activité surfacique a pu être abaissée en dessous de 50 Bq/cm2 avec une passe supplémentaire.A gel (HNO 3 1M / H 3 PO 4 1M) was in particular prepared and tested in terms of decontamination on aluminum flanges from a pneumatic transfer network of a nuclear waste reprocessing plant. Decontamination factors of the order of 14 (Cs 137, Eu 154) were obtained after a single gel pass (Cs 137: from 1300 Bq / cm 2 to 110 Bq / cm 2 ) and the surface activity was be lowered below 50 Bq / cm 2 with an extra pass.

Exemple 4Example 4

Pour décontaminer de l'acier inoxydable ou de l'inconel (marque de commerce), un gel oxydant selon l'invention a été préparé en utilisant de l'acide nitrique 3 M et 0,1 à 0,3 M de Ce (IV).To decontaminate stainless steel or inconel (trademark), an oxidizing gel according to the invention was prepared using 3 M nitric acid and 0.1 to 0.3 M Ce (IV). ).

Les gels sèchent rapidement en moins de 3 heures et se décollent facilement au pinceau. Les résultats de corrosion obtenus par enduction de 500g/m2 sur de l'inconel sont tout à fait intéressants puisque l'érosion généralisée est effet comprise entre 0,1 et 0,3 µm.The gels dry quickly in less than 3 hours and easily peel off with a brush. The corrosion results obtained by coating 500 g / m2 on inconel are quite interesting since generalized erosion is effect between 0.1 and 0.3 μm.

Claims (22)

  1. Method for treating a surface with a treatment gel, said method comprising in this order the following steps:
    - applying a treatment gel on the surface to be treated, said treatment gel consisting of a colloidal solution comprising:
    • 5 to 25% by weight of an inorganic viscosing agent or a mixture of inorganic viscosing agents based on the weight of the gel,
    • 0.5 to 4 mol/l of an active treatment agent, and
    • optionally 0.05 to 1 mol/l of an oxidizing agent with a normal oxidation-reduction potential E0 larger than 1.4 V in a strong acid medium or of the reduced form of this oxidizing agent,
    - maintaining the treatment gel on the surface to be treated at a temperature and relative humidity such that the gel dries and has the time to treat the surface before forming a dry and solid residue, and
    - removing the dry and solid residue from the treatment surface.
  2. Treatment method according to claim 1, wherein the drying temperature is between 20 and 30°C, and the relative humidity between 20 and 70%.
  3. Treatment method according to claim 1, wherein the mixture of silicas represents 5 to 15% by weight of the gel.
  4. Treatment method according to claim 1, wherein the mixture of silicas represents 5 to 10% by weight of the gel.
  5. Treatment method according to claim 1, wherein the precipitated silica represents 0.5% by weight of the gel and the pyrogenated silica represents 8% by weight of the gel.
  6. Treatment method according to any ane of the claims 1 to 5, wherein the active treatment agent is an inorganic acid or a mixture of inorganic acids.
  7. Treatment method according to claim 6, wherein the inorganic acid is selected from hydrochloric acid, nitric acid, sulphuric acid, phosphoric acid or a mixture thereof.
  8. Treatment method according to any of claims 1 to 5, wherein the gel comprises an active treatment agent which is an inorganic base present in a concentration from 0.5 to 2 moles per litre of gel.
  9. Treatment method according to claim 8, wherein the inorganic base is selected from soda, potash or a mixture thereof.
  10. Treatment method according to any of claims 1 to 5, wherein the treatment gel comprises from 0.5 to 1 mol/l of an oxidizing agent with a normal oxidation-reduction potential E0 larger than 1.4 V in a strong acid medium selected from Ce (IV), Co (III) or Ag (II).
  11. Treatment method according to claim 1, wherein the treatment gel comprises from 5 to 15% by weight of silica, 0.5 to 2 mol/l of nitric acid and from 0.1 to 0.5 moles per litre of gel, of Ce (NO3)4 or (NH4)2Ce(NO3)6.
  12. Treatment method according to claim 1, wherein the treatment gel is applied on the surface to be treated in an amount from 100 to 2000 g of gel per m2 of surface.
  13. Treatment method according to claim 1, wherein the dry and solid residue is removed from the treated surface by brushing and/or by suction.
  14. Use of a method according to any of claims 1 to 13, for degreasing a surface, for removing an oxide layer from a metal surface or for decontaminating a surface.
  15. Method for decontaminating a facility comprising removal of dust from the installation to be treated, followed by a treatment of the facility by means of a method according to any of claims 1 to 13.
  16. Method according to claim 15, wherein the facility is a ventilation shaft of a nuclear facility.
  17. Gel for treating a surface, consisting of a colloidal solution comprising:
    • 5 to 25% by weight of an inorganic viscosing agent or of a mixture of inorganic viscosing agents based on the weight of the gel,
    • 0.5 to 4 mol/l of an active treatment agent, and
    • optionally from 0.05 to 1 mol/l of an oxidizing agent with a normal oxidation-reduction potential E0 larger than 1.4 V in a strong acid medium or of the reduced form of this oxidizing agent.
  18. Gel for treating a surface according to claim 17, consisting of a colloidal solution comprising:
    wherein the mixture of silicas represents 5 to 15% by weight based on the weight of the gel, and
    wherein the active treatment agent is an inorganic acid or a mixture of inorganic acids.
  19. Treatment gel according to claim 17, wherein the mixture of pyrogenated and precipitated silicas represents 5 to 10% by weight of the gel.
  20. Treatment gel according to claim 17, wherein the precipitated silica represents 0.5% by weight of the gel and the pyrogenated silica represents 8% by weight of the gel.
  21. Treatment gel according to claim 18, wherein the inorganic acid is selected from hydrochloric acid, nitric acid, sulphuric acid, phosphoric acid or a mixture thereof.
  22. Treatment gel according to claim 17 or 20, wherein the oxidizing agent with a normal oxidation-reduction potential E0 larger than 1.4 V in a strong acid medium is selected from Ce (IV), Co (III) or Ag (II).
EP02760387A 2001-07-17 2002-07-15 Method for treating a surface with a treating gel and treating gel Expired - Lifetime EP1421165B1 (en)

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FR0109520A FR2827530B1 (en) 2001-07-17 2001-07-17 PROCESS FOR TREATING A SURFACE WITH A TREATMENT GEL, AND TREATMENT GEL
PCT/FR2002/002509 WO2003008529A1 (en) 2001-07-17 2002-07-15 Method for treating a surface with a treating gel and treating gel

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Families Citing this family (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3914721B2 (en) * 2001-06-25 2007-05-16 株式会社平間理化研究所 Non-aqueous resist stripping solution management apparatus and non-aqueous resist stripping solution management method
FR2827530B1 (en) * 2001-07-17 2004-05-21 Commissariat Energie Atomique PROCESS FOR TREATING A SURFACE WITH A TREATMENT GEL, AND TREATMENT GEL
US8009696B2 (en) * 2004-08-06 2011-08-30 Ipeak Networks Incorporated System and method for achieving accelerated throughput
CN1332398C (en) * 2004-10-15 2007-08-15 中国人民解放军总参谋部工程兵科研三所 Peeling off type pressed detergent
US20060151434A1 (en) * 2005-01-07 2006-07-13 The Boc Group, Inc. Selective surface texturing through the use of random application of thixotropic etching agents
FR2891470B1 (en) * 2005-10-05 2007-11-23 Commissariat Energie Atomique ASPIRABLE GEL FOR DECONTAMINATION OF SURFACES AND USE
FR2962046B1 (en) * 2010-07-02 2012-08-17 Commissariat Energie Atomique BIOLOGICAL DECONTAMINATION GEL AND METHOD OF DECONTAMINATING SURFACES USING THE GEL.
FR2984170B1 (en) 2011-12-19 2014-01-17 Commissariat Energie Atomique DECONTAMINATION GEL AND METHOD OF DECONTAMINATING SURFACES BY SOAKING USING THE GEL.
JP5846997B2 (en) * 2012-03-30 2016-01-20 鹿島建設株式会社 Film forming composition, surface cleaning method, radioactive substance removing method, surface protecting method, and film
FR2990364B1 (en) 2012-05-11 2014-06-13 Commissariat Energie Atomique METHOD FOR RADIOACTIVE DECONTAMINATION OF EARTH BY DISPERSE AIR FLOTATION FOAM AND FOAM
FR3003869B1 (en) 2013-03-29 2015-05-01 Commissariat Energie Atomique PIGMENT DECONTAMINATION GEL AND METHOD OF DECONTAMINATING SURFACES USING THE GEL.
FR3003763B1 (en) 2013-03-29 2015-05-15 Commissariat Energie Atomique ALKALINE OXIDIZING GEL FOR BIOLOGICAL DECONTAMINATION AND METHOD FOR BIOLOGICAL DECONTAMINATION OF SURFACES USING THE GEL.
CN103695205B (en) * 2013-12-03 2016-01-20 中国人民解放军总参谋部工程兵科研三所 A kind of Self-broken decontamination liquid
FR3014336B1 (en) 2013-12-05 2016-01-22 Commissariat Energie Atomique USE OF AN ALKALINE OXIDIZING GEL FOR REMOVING BIOFILM ON A SURFACE OF A SOLID SUBSTRATE.
US9969549B2 (en) 2014-03-24 2018-05-15 The Boeing Company Systems and methods for controlling a fuel tank environment
FR3027310B1 (en) * 2014-10-15 2017-12-15 Commissariat Energie Atomique GEL FOR REMOVING GRAFFITI AND METHOD FOR REMOVING GRAFFITIS USING THE GEL.
FR3053897B1 (en) 2016-07-13 2022-05-20 Commissariat Energie Atomique ADSORBENT AND PHOTOCATALYTIC DECONTAMINATION GEL AND METHOD FOR DECONTAMINATING SURFACES USING THIS GEL
FR3054839B1 (en) 2016-08-05 2020-06-26 Commissariat A L'energie Atomique Et Aux Energies Alternatives SUCTION GEL AND METHOD FOR ELIMINATING RADIOACTIVE CONTAMINATION CONTAINED IN AN ORGANIC LAYER ON THE SURFACE OF A SOLID SUBSTRATE.
US20180094217A1 (en) * 2016-09-30 2018-04-05 General Electric Company Method and material for cleaning metal surfaces
RU2655525C2 (en) * 2016-10-05 2018-05-28 Федеральное государственное бюджетное образовательное учреждение высшего образования "Волгоградский государственный медицинский университет" Министерства здравоохранения Российской Федерации ГБОУ ВПО ВолгГМУ МЗ РФ Non-aqueous cleaning method for removing surface contaminants from orthopedic structures
RU2662531C1 (en) * 2017-05-31 2018-07-26 Кирилл Игоревич Мыльников Chamber for processing plastic products
FR3083712B1 (en) 2018-07-11 2022-01-21 Commissariat Energie Atomique METHOD FOR DECONTAMINATING A GAS MEDIUM CONTAMINATED BY CONTAMINATING SPECIES IN SUSPENSION.
RU187811U1 (en) * 2018-11-14 2019-03-19 Александр Николаевич Костин DEVICE FOR FINISHING SURFACE OF PLASTIC PRODUCTS
RU189421U1 (en) * 2019-02-11 2019-05-22 Александр Николаевич Костин PORTABLE DEVICE FOR FINISHING THE SURFACE OF PLASTIC PRODUCTS
CN112760659B (en) * 2020-12-02 2022-09-27 中国辐射防护研究院 Oxidation decontamination gel and preparation method and application thereof
CN114672816B (en) * 2022-01-07 2024-04-05 航天科工防御技术研究试验中心 Composition for removing corrosion on aluminum alloy surface as well as preparation method and application thereof
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Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3578499A (en) * 1968-08-02 1971-05-11 Grace W R & Co Gelling composition for general purpose cleaning and sanitizing
FR2380624A1 (en) * 1977-02-09 1978-09-08 Commissariat Energie Atomique Radioactive decontamination by applying gel contg. decontaminant - then rinsing off or removing when dry
US4365516A (en) * 1978-01-06 1982-12-28 Rockwell International Corporation Ultrasonic couplant gel compositions and method for employing same
JPS5939511B2 (en) * 1982-08-05 1984-09-25 正己 小林 Gel derusting agent
FR2656949B1 (en) * 1990-01-09 1994-03-25 Commissariat A Energie Atomique DECONTAMINANT GEL AND ITS USE FOR RADIOACTIVE DECONTAMINATION OF SURFACES.
US5264010A (en) * 1992-04-27 1993-11-23 Rodel, Inc. Compositions and methods for polishing and planarizing surfaces
FR2695839B1 (en) * 1992-09-23 1994-10-14 Commissariat Energie Atomique Reducing decontaminating gel and its use for surface decontamination, in particular of nuclear installations.
US5782940A (en) * 1996-03-15 1998-07-21 Carborundum Universal Limited Process for the preparation of alumina abrasives
FR2746328B1 (en) * 1996-03-21 1998-05-29 Stmi Soc Tech Milieu Ionisant ORGANOMINERAL DECONTAMINATION GEL AND ITS USE FOR THE DECONTAMINATION OF SURFACES
FR2781809B1 (en) * 1998-07-31 2002-06-07 Commissariat Energie Atomique DEGREASING COMPOSITION AND METHODS USING THE SAME
US6455751B1 (en) * 1999-03-03 2002-09-24 The Regents Of The University Of California Oxidizer gels for detoxification of chemical and biological agents
FR2798603B1 (en) * 1999-09-20 2002-03-01 Tech En Milieu Ionisant Stmi S ORGANIC DECONTAMINATION GEL AND ITS USE FOR DECONTAMINATION OF SURFACES
US6616910B2 (en) * 2000-05-05 2003-09-09 Institut Francais Du Petrole Process for preparation of an EUO-structural-type zeolite, the zeolite that is obtained and its use as catalyst for isomerization of C8-aromatic compounds
FR2827530B1 (en) * 2001-07-17 2004-05-21 Commissariat Energie Atomique PROCESS FOR TREATING A SURFACE WITH A TREATMENT GEL, AND TREATMENT GEL
US6605158B1 (en) * 2001-10-12 2003-08-12 Bobolink, Inc. Radioactive decontamination and translocation method

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JP2004535510A (en) 2004-11-25
US20040175505A1 (en) 2004-09-09
CN1273578C (en) 2006-09-06
DE60214567T2 (en) 2007-09-13
UA82465C2 (en) 2008-04-25
JP4334339B2 (en) 2009-09-30
FR2827530B1 (en) 2004-05-21
DE60214567D1 (en) 2006-10-19
ATE338806T1 (en) 2006-09-15
US20060032518A1 (en) 2006-02-16
EP1421165A1 (en) 2004-05-26
US7713357B2 (en) 2010-05-11
US7718010B2 (en) 2010-05-18
FR2827530A1 (en) 2003-01-24
WO2003008529A1 (en) 2003-01-30
RU2004104467A (en) 2005-05-10
ES2271318T3 (en) 2007-04-16
CN1592778A (en) 2005-03-09

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