FR2709969A1 - Process and adsorbent material for combating odorous and noxious substances - Google Patents

Abstract

The invention relates to a method for controlling emissions of odorous and harmful substances. The method is characterized in that the emission source is covered directly with a material which contains adsorbent particles. It also relates to an adsorbent material containing a planar support material serving as a barrier layer permeable to water vapor, and a layer disposed on the barrier layer and containing adsorbent particles. Application: Building renovation.

Description

The present invention relates to a method of cleaning premises

  loaded with harmful substances, as well as materials that can be used for this purpose. The growing knowledge of the world around us, coupled with very sensitive methods of analysis, is revealing more and more to the public the pollution of our environment by harmful substances. As a result, for buildings loaded with noxious or odorous substances, there is an increased need to remediate these buildings with a minimum of expense. It has also been recognized that the presence of harmful substances must be established with simple means in order to perceive the need for sanitation and the success of sanitation. We consider here as harmful substances substances which a small amount already triggers in humans irritations, allergies or diseases. These substances include wood preservatives such as pentachlorophenol (PCP) and lindane, plasticizers such as polychlorinated biphenyls (PCB), or formaldehyde; the latter has been and is still used in particle board and has been suspected in the meantime to be carcinogenic. Hydrocarbons which are optionally aromatic, or their chlorinated derivatives, can also be released as harmful substances in the sense indicated above, for example varnish,

paints or adhesives.

  Particularly problematic harmful substances are PCBs which have been used for example as plasticizers in sealing materials, in particular for the construction of prefabricated elements. Recent knowledge has shown that over time, PCBs diffuse sealant in contiguous concrete elements as well as are released into the ambient air by the seals. By air exchange, the air loaded with PCB is distributed throughout the building. The PCB released from the seals, known as primary sources, partially precipitates in the premises by binding to particles, but also dissolves largely in wall paints and plastics. It follows that after a certain period of disengagement, a series of so-called secondary emission sources has been formed, of which, in particular, coated walls and ceilings may be mentioned. These secondary sources usually contain such a large amount of PCBs and constitute such a large emission area that the elimination of the seals alone can not produce a lowering of the PCB concentration in the ambient air below. precautionary limits. Carpets can be another source of harmful and odorous substances. The emissions occur, for example, by the fact that the raw materials of these products react under the influence of moisture and / or under the influence of constituents of the material forming the substrate. Even after the flooring has been removed, the floor continues to emit odorous and noxious substances, so that until now, the entire floor has had to be removed or soil laid

  intermediate with posterior aeration.

  Additives incorporated into the building material itself are another source of unpleasant emissions, sometimes harmful to health. For example, many constructions are concerned by ammonia emissions that must be attributed to the use of ammonium salts, urea or organic amines in the broadest sense as agents for protection of concrete and mortar against freezing. It is also possible to mention, as a cause of the amine emanation, also a previous use of a room, for example for the purpose of animal rearing, which leads to the fact that the building elements remain for a long time in contact with each other. with harmful substances coming from the air. If we remove the sources of these substances, for example to

  converting the building from a barn into a residential or commercial space, we are witnessing a re-emission of substances from secondary sources, wall surfaces and ceilings. This situation is comparable in its cause and effect to the above-mentioned problem of PCB pollution.

  DE-A-38 18 993 discloses a method of cleaning premises loaded with harmful substances. However, in this case, it is the ambient air loaded with harmful substances which is purified. To achieve this, the air is passed through adsorbent materials by appropriate measures, artificially or by its own circulation only. For example, the air charged with harmful substances passes through adsorption towers loaded with adsorbents. Another possibility made known by this document is to pass the air on planar bodies of large area, loaded with adsorbent materials, for example curtains. However, this method has the decisive disadvantage of simply accessing the already charged ambient air. This leads to the purified air always being remixed with the air laden with harmful substances and thus obtaining a dilution effect in the best case. DE-OS-40 28 434 discloses a possibility of decontaminating sealing compositions containing harmful substances. By appropriate means, the sealed material, which constitutes the primary source, is then cut and decontaminated. The method therefore intervenes only on the primary source. But as already described above, harmful substances from secondary sources, namely wall surfaces and ceilings, also very considerably charge the ambient air; with the process indicated above, we can not clean up

these secondary sources.

  The problem of the present invention is to make available a method of cleaning premises loaded with harmful substances. This problem is solved by the fact that the emission source is directly coated with a material that contains adsorbent particles. The main advantage then is that suitable materials according to the invention avoid the passage of harmful substances through the covering layer and, consequently, transfer of harmful substances into the ambient air. The process according to the invention thus undertakes the remediation of the emission sources loaded with harmful substances at a stage earlier than the processes which are known according to the state of the art. In the process according to the invention, the harmful substances are therefore generally prevented from passing into the ambient air or to be able to form secondary emission sources, whereas the processes described up to now are based on the elimination of harmful substances from the ambient air which in

is charged.

  The total recovery, according to the invention, of the source of emission offers two decisive advantages: no harmful substance no longer arrives in the space and the adsorption occurs where the concentration of harmful substances is maximum. By the method according to the invention, it has for example been possible to reduce the radon concentration in residential buildings to such an extent that even in premises previously heavily loaded, it has been possible to respect

  limit values that serve as health precautions.

  An embodiment of the method according to the invention resides in the fact that the neighboring elements or objects of the primary sources of emission are firstly

  coated with materials that contain adsorbent moieties.

  This recovery must prohibit the release of harmful substances that arise from the fact that these substances diffuse from the primary sources of emission in these neighboring elements and can emerge in the ambient air by migrating to the surface of these elements of construction. In another embodiment of the present invention, the material is selected from the group of open pore foams, nonwovens, and inorganic and organic binders. In particular, it is an open pore foam 0.5 to 5 mm thick, preferably a cross-linked polyurethane foam which contains finely ground adsorbent particles and a binder. Similarly, the material may contain a fiber web of 0.1 to 2.0 mm thick, which contains the adsorbent particles and the binder. According to another embodiment, the material is a paint, a coating, a sound-absorbing coating or a whitewash, which contains the

adsorbent particles.

  The material according to the invention, which contains the adsorbent particles, can equally well be a

  carpet, preferably an upholstery of carpet backing.

  The concept of binder is addressed to all substances that bind together the same substances or substances of different nature. For example, in the case of a coating according to the invention, it is all non-hydraulic, hydraulic and latent hydraulic binders (gypsum, water glass, Sorel cement, anhydride, magnesia binder, white lime, lime hydraulic, cement, blast furnace slag, etc.). In the case of foams and open-pored nonwovens, the binders are for example all natural or synthetic substances which are used as solutions, dispersions, melts or liquid systems of reactive plastics after formulation (for example by resins and appropriate plasticisers, and if appropriate pigments and fillers), for the

  binding of materials of different nature.

  With regard to the use of a coating or a wash, containing adsorbent particles, for the process according to the invention, particularly good results have been obtained with compositions which were at the same time used as a sound-absorbing coating . This may be due to the high porosity which at the same time allows good accessibility to the adsorbent material. The coating is generally provided as a dry blend containing up to 50% by weight of adsorbent particles and is pulped prior to use. Similarly, the soil to be sanitized can be covered, by the process according to the invention, with an additional whitewash which contains

  up to 50% by weight of adsorbent particles.

  Another embodiment of the process according to the invention lies in the fact that the adsorbent materials can also be incorporated into a wallpaper adhesive. This adhesive may for example consist of a 40% dispersion of ethyl acrylate to which 60% by weight of ground activated carbon is added and suspended in water. The walls and ceilings can be coated with a layer about 300 gm thick on which we put a traditional wallpaper. adhesion

is good.

  If non-moisture-sensitive molecular sieves are used as the adsorbent, a white background shade can be added to which color pigments can be added at will. Effective control of the layer thickness remains important to locally avoid weak points due to insufficient amounts of adsorbent material. But instead of being incorporated into the wallpaper glue, the adsorbent materials can also be incorporated into a paint which must then be applied in sufficient thickness. For this purpose, for reasons of appearance, hardly used active carbon, but rather molecular sieves. The paints are suitable mainly for irregularly shaped or non-planar bodies (cables, tubes) or crossings to be covered. In producing materials for the process according to the invention, it must be ensured that the material or binder does not contain substances that can be absorbed by the adsorbent particles. The specialist in this field knows of appropriate solutions that there is no need to comment here in more detail. However, it is recommended to confirm the choice of binder, for example by

a control test.

  Another embodiment of the process according to the invention lies in the fact that the material comprising the adsorbent particles is a wallpaper on which is applied a cross-linked polyurethane foam 1 to 5 mm, loaded with adsorbent particles. Such

  Foams are preferably compressed and dried with a mixture of ground activated carbon and a binder dispersion.

  In this case, a coal load of up to 200 g / m 2 is reached, the binder / char ratio on a dry basis then varying from 1: 1 to 1: 5.

  Another embodiment according to the invention lies in the fact that the material containing adsorbent particles is a support layer formed of a flat substrate of the group of paper, wallpapers or textile flat bodies, for example fabrics, knits, fiber fleeces or fiberglass fabrics and the adsorbent particles are applied to this support layer. The latter advantageously forms, with the particles disposed on it, a test strip, which is applied to the construction elements, covered or not, in order to determine if there are infiltrations of toxic substances for the environment through stopping layers

  or if there is release of such substances.

  A planar support material which can be used for the processes according to the invention, which contains globules of activated carbon, is described in the documents

EP-A-118 618 and EP-A-90 173.

  With respect to the emission source, these test strips according to the invention can be applied with their adsorbent materials turned both outwards and inwards, in order to detect, for example in the latter case, infiltrations through a wallpaper endowed with adsorbent properties or through floor coverings endowed with the same properties. A 20 x 100 mm strip which contains about 0.5 g of activated carbon has been found to be very suitable as a test strip and very convenient. An embodiment according to the invention consists of a double-sided adhesive tape, one side is lined with adsorbent particles and the other is covered with a silicone protective paper, to be removed before use. The tape is packaged in a gas-tight envelope, which protects the activated carbon until it is used and which

  is also used for re-dispatching to the analysis laboratory.

  The bands can be applied by a slight pressure for example to the underside of seats, tables, etc.

from where we can then detach them.

  Another application of these test strips is the monitoring of the remediation of buildings containing harmful substances, which can be illustrated with an example. As already described above, evaporation of PCB in panel constructions, contaminations involving large areas of walls and ceilings, which can be neutralized by covering the contaminated surface of wallpapers containing activated carbon. Here it is advantageous to be able to recognize at the desired time a possible infiltration of PCB through the wallpaper. For this purpose, the test strip containing the adsorbent particles is adhered to the surface of the adsorbent wallpaper, with orientation towards the wall side. An adhesive tape is preferably used overlapping the test strip (1 cm overlap on all sides) so

  the adsorbent layer is not touched by the adhesive.

  On the inwardly facing side, a barrier layer, for example an aluminum foil, may be provided to increase the efficiency of the strip. or a flooring emitting odorous and noxious substances, an embodiment of the method according to the invention consists in placing between the floor or the contaminated floor covering and the new carpet or other new floor covering, a layer or material by

  which odorous and noxious substances are adsorbed.

  In this method according to the invention, for example, on a flexible support material, granular or spherical adsorbent materials, preferably activated carbon, are adhesively adhered to by means of a spot-printed adhesive composition. porous polymers and are coated with a lightweight textile material permeable to air. A web support material which can be used for this process according to the invention, which contains globules of activated carbon, is described in documents EP-A-118 618 and

EP-A-90 073.

  Another possibility is to provide the support material with a water vapor permeable coating which acts as a fixing material for the adsorbent particles. The adsorbent particles are dispersed in the mass of this coating. After drying, the layer thus produced from the adsorbent materials is covered with a light textile plane body. By the coating on the whole surface, is established next to the adsorbent layer an additional barrier layer, which allows "breathe" the soil because of its permeability to water vapor. The use of an adsorbent material that is not part of the carpet then allows to put any carpet on this material. But the adsorbents can also be directly placed on the floor of the carpet. This presupposes the presence of a high quality posterior coating, which at the same time serves as a binding material for the adsorbent particles. This posterior coating may furthermore be covered with a light textile plane body. When operating in this way, the adsorbent particles are freely accessible in a proportion of at least 50%, preferably between 70 and 80%. This is an advantage from the point of view of the adsorption kinetics, since no adhesive layer has to be passed through. Activated carbon, which is incorporated for example in the form of a powder with a posterior coating, is on the other hand less effective in

  because of the reduced accessibility of the outer surface.

  Another embodiment of the process according to the invention is that the material containing the adsorbent particles is a composite material which consists of a support layer formed from a web support material from the group of paper, wallpapers or textile flat bodies, for example, fabrics, knits, fiber veils or fiberglass fabrics, with a layer on the support layer containing the adsorbent particles and a cover layer disposed on this layer containing the adsorbent particles. This composite material therefore has a sandwich structure comprising the support layer, the adsorbent particles and the covering layer. The adsorbent particles are preferably applied to the support layer by means of a preparation containing an adhesive material. This adhesive material consists of organic binders, especially a dispersion of synthetic material or a two-component system poor in solvent, or it is selected from the group of latex, for example natural latex. This preparation containing the adhesive material may be applied in points or in a layer covering the entire surface. Since, for reasons related to building physics, the water and air permeability of the materials used in construction play an important role, the adhesive material must be permeable in nature

  with water vapor, especially in the case of a layer covering the entire surface.

  The covering layer which is used in the materials that can be used for the process according to the invention is a material which supports the group of paper, wallpapers or flat textile bodies, for example fabrics, knits, fiber sails. or fiberglass fabrics. This covering layer may be lined on the material containing the adsorbent particles, preferably by dots or by a thin sheet of fuse adhesive. A composite material that can be used for the process according to the invention can for example be produced as follows. The support facing the interior space (textile planar body, special paper or fiberglass fabric) is provided with a layer permeable to water vapor covering the entire surface, which is at the same time the material for fixing the adsorbent particles in grains or globules. The particles of adsorbent material are spread on the layer before drying. Excess is removed by aspiration. The adsorbent layer is then covered for example with a light textile material to protect it from the adhesive with which the composite material is bonded to the building element. Lightweight polyester fine mesh webs can advantageously be used for coating.

  bearing a fuse adhesive.

  The layer applied over the entire surface has the decisive advantage that even in the case of using a loose textile backing material, this material can be painted without the wall painting covering the adsorbent particles, altering or rendering them. inaccessible in any other way to harmful substances that must be adsorbed. Dispersions with which water vapor permeable layers can be established are for example the products "Plextol" from the firm Rôhm GmbH or the products of the types "Impranil" and "Impraperm" from the firm Bayer AG.5 Another means of protecting the adsorbent particles contained in the material intended for the process according to the invention, from the penetration of the paint, is to turn the support layer of the adsorbent particles towards the wall and to cover them themselves with the outer material, then using as an adhesive layer between the adsorbent particles and the outer material a fuse sheet of adhesive having slots. This ensures that enough moisture can penetrate, but not

the painting.

  However, for the application of paint, it is preferable to use paints which contain

  little or no solvent.

  In another embodiment of the invention, there is preferably an additional barrier layer, preferably a water vapor permeable barrier layer, on the side of the composite material opposed to the source of the emission, that is to say on the support layer or the covering layer. The barrier layer is generally disposed within the composite material on the

  side of the adsorbent layer opposite to the emission source.

  The invention also relates to an adsorbent material that contains a planar support material formed as a water vapor permeable barrier layer, surmounted by a layer containing adsorbent particles. In another embodiment of the invention, this adsorbent material may contain another covering layer which is arranged

  on the layer containing the adsorbent particles.

  Another adsorbent material according to the invention, in the form of a composite material, contains a web support material, another water vapor permeable barrier layer disposed on said support material and a layer lying thereon. on this barrier layer and containing adsorbent particles. This adsorbent material may contain, in another embodiment of the invention, an additional cover layer which is disposed on the layer containing the adsorbent particles. The role of the barrier layer is to prolong the contact time between the harmful substances and the adsorbent particles by reducing the migration speed of the harmful substances from the emission source towards the surface of the composite material. Another advantage of the barrier layer is that it prevents persistently adsorbable, low volatility gases from migrating air from the interior space into the adsorbent layer and reducing the adsorption efficiency thereof. for example against radon emanating from the wall. It is preferably used when porous planar bodies which are permeable to air are selected as support material. Such a barrier layer is preferably permeable to water vapor so as not to impede the respiration of

masonry.

  At the same time, the barrier layer can constitute the material for fixing the adsorbent particles. But it can also consist of a sheet having slots applied in lining on the inner face of the outer layer of the composite material, preferably a sheet having slots and carrying a fuse adhesive, which is bound to the other adsorbent particles. In another embodiment, the barrier layer may be a latex layer or a layer of latex paint, which is applied to the outer side of the composite material, rotated

towards the interior of the room.

  With regard to the adsorption of radon by means of the process according to the invention, it has appeared that the use as a barrier layer of a slotted sheet carrying a fuse adhesive with which the outer layer of recovery of the side of the piece had been applied in liner on the adsorbent layer, was very effective. Depending on the bonding temperature, the passage of air is reduced by about 90% at the same time as the radon adsorption is considerably improved. The passage of moisture is then more than enough, so there is no risk of moisture build up in the masonry. Another method according to the invention for the adsorption of radon may be to use a material in which the rear face of the outer material is provided with a layer permeable to water vapor, which serves at the same time layer

  adhesive for the granules or globules of adsorbent material.

  The liner is then lined on the adsorbent layer produced after the coating process, which may be, for example, a textile material or a paper. In both cases mentioned above, the radon first comes into contact with the adsorbent layer. The part of the radon that has not been fully adsorbed meets the barrier layer and is curbed by this layer, so that

  the adsorption process can continue.

  In another embodiment of the process according to the invention and adsorbent materials according to the invention, the side of the material or of the composite material (support layer or covering layer) facing the emission source is a layer separation device whose role is to allow removal of the composite material such that the latter can be removed from the emission source and decontaminated. The removal must then be understood in the sense that, in particular, the adsorbent particles may be removed in connection with the support layer and entirely from the emission source. This separation layer may advantageously be a paper or a web that can be split or it consists of two

  fiber sails easy to separate. Practical tests carried out by the Applicant have shown that in the

  case of adsorption of PCBs on activated carbon, because of the favorable adsorption equilibrium, the PCB is "sucked" from the emission source5 (for example from a contaminated wall) and the wall is virtually devoid of of PCBs after a few years. The layer then has the particular purpose of simplifying, for example, the detachment of a wallpaper from the emission source in order to send it to a treatment site according to the standards relating to the harmful substances, for example a production plant. incineration of waste. PCB adsorbents should be detected as completely as possible. In order to achieve this goal, the composite material of the support material or wallpaper must have a weakening point (point for breaking). This possibility is afforded by the following example structure: the outer textile material carries on the side facing the wall grains of adsorbent material which adhere to the textile material with a discontinuously applied adhesive. The adsorbent particles are covered by a divisible paper. Divisible papers have a relatively well-glued surface, but they are barely stuck on the inside and that's why they can be divided. When tearing, one half remains applied to the wall and can serve as a substrate for a new wallpaper, while the other half continues to cover the adsorbents; therefore, any loss of

adsorbents is avoided.

  Another possibility of removing a wallpaper without loss of adsorbents is to make the adsorbent coverage facing the wall strong enough so that it does not tear when removing the wallpaper. The glue bottom can advantageously be everything

first moistened.

  An advantage of the composite material described above

  In general, it is possible for harmful substances to move freely inside the adsorbent layer until they are adsorbed. If, due to a particular nature of the emission source, stronger discharges of harmful substances occur in places, they can extend laterally without hindrance into the adsorbent layer (no local overload) by means of the coating layer. stop and stratified structure. Adsorbent particles are still available in large quantities in all directions and allow even distribution of harmful substances. In case of recovery without insertion of adsorbents, that is to say for example with aluminum foil, it occurs in case of deterioration of the effects of migration and crossings

massive.

  On the other hand, slight local alterations of the composite material according to the invention, for example by drill holes, are completely harmless, because the action of an adsorbent wallpaper, for example, is based on the fixing of the harmful substances. in the area around the source of emission and does not constrain

  not to a total partitioning on the whole surface.

  Another form of implementation of the process according to the invention lies in the fact that the materials containing the adsorbent particles are in the form of strips which are, for example, disposed over joints sealed with compositions containing harmful substances. or are pressed into these joints. These strips can still advantageously be covered with a material which is suitable for the process according to the invention, so as to exclude with absolute safety a passage of harmful substances in space. Since the sealing material of the seals is generally slightly set back, there is sufficient room for a thick strip of adsorbent material; rather large amounts of adsorbent particles can lodge in this recessed space, so that safety can still be guaranteed after many years. The adsorbent particles that can be put in place and used for the process according to the invention and for the adsorbent materials in accordance with the invention are activated charcoal powder, activated carbon globules, activated carbon granules, ionic exchangers carbonized and activated, spherical pitch coal, hydrophobic molecular sieves, molded from hydrophobic molecular sieves or porous polymers. The adsorbent particles, especially activated carbon, advantageously have a surface area of at least 900 m 2 / g. The activated carbon globules and granules preferably have a diameter of 0.1 to 2.0 mm, especially 0.3 to 1.0 mm. The adsorbent particles are preferably present in an amount of 5 to 400 g / m 2,

in particular from 10 to 250 g / m2.

  The production of carbonized and activated ion exchangers is described in document DE-A-43 04 026. The materials according to the invention generally contain

  up to 70% by weight of adsorbent particles.

  Many processes are suitable for the application of the adsorbent particles, for example on the support material. Thus, as described for example in DE-A-32 11 322, small heaps of an active carbon paste and a binder dispersion can be deposited by rotary screen printing, which makes it possible to obtain

  coating weights up to 100 g / m2.

  The use of activated carbon in spherical particles, which is adhered by a material applied in points to a textile plane body, is described in DE-A-33 04 349. An adsorbent material which is suitable for the present invention. The invention is coal in spherical particles, based on pitch. Thus, for example in the case of the use of spherical carbon particles of a

  diameter of 0.3 to 0.8 mm, up to 1000 globules per cm2 can be applied to the support material of the test strips according to the invention or of the composite material.

  This corresponds to more than 20 mg / cm 2 of activated carbon, which is almost freely accessible, since the adhesive material only closes 10 to 15% of the pores. With a specific surface area of 1000 to 1200 m 2 / g and a microscopic pore volume of 0.3 ml / g for a pore diameter of 0.5 to 1.2 nm, and a mean point of 0.8 to 0, At 9 nm, the spherical particle carbon is particularly advantageous for use in the present invention. An important fact is that the microscopic pores are relatively narrow, because the adsorption forces are then maximal. But on the other hand, the microscopic pores must be large enough not to retain the harmful substance molecules that are not very small, for example the PCB molecules. This is why pore diameters of 0.6 to 1.0 nm are very favorable. Such pore diameters are observed, for example, in the case of activated carbons based on pitch (charcoal in spherical particles), based on coconut shells and on the basis of certain coals. The harmful substances are strongly adsorbed in these materials

and are kept there permanently.

  A homogeneous charge of the support layer with the adsorbent particles is important for the efficiency of the composite material. It is guaranteed in particular

  when activated charcoal is used in globules.

  In addition to coal in globules, it is also possible to use basically coal in granules or shale (with particle diameters of 0.3 to 2 mm). It is however preferable to use carbon in globules because of its smooth abrasion-resistant surface

  as well as the optimal coating that it provides.

  In order for certain harmful substances to be adsorbed, it may be necessary to impregnate the adsorbent particles and to use various adsorbent particles: pure activated carbon for harmful high-boiling substances, for example PCB and PCP; pure activated carbon, preferably with very small microscopic pores, for solvents; active carbon impregnated with acid, for example phosphoric acid for the adsorption of ammonia and amines; activated carbon impregnated with a basic substance, for example potassium carbonate,

  for acid gases; charcoal impregnated with 2-amino-1,3

  propanediol or trimethanolamine for the adsorption of formaldehyde; coal impregnated with a sulphide substance for the adsorption of mercury vapor; activated carbon impregnated with copper salts for the adsorption of harmful substances containing sulfur and containing nitrogen, to quote

than the most important.

  With regard to ammonia emissions from masonry, the application of wallpapers containing active carbon particles impregnated with phosphoric acid has given very good results. Such wallpapers basically have the laminated structure described above, wherein granular or globular adsorbent materials are located between two planar textile or paper bodies, one of which is the support layer of the adsorbent particles and the other is the cover layer for these particles. In view of the adsorption of harmful substances of high boiling point in accordance with the process of the invention, it is also advisable to use porous polymers such as, for example, the resins "XUS" from the firm DOW-Chemical Company. . Carbonized and activated cationic exchangers, for example based on sulphonated styrene / divinylbenzene copolymers, which have a great similarity with activated carbon in this case, should also be used.

  which concerns their physical properties.

  For the purposes of the process and the material according to the invention, the external surface of the adsorbent particles

  is freely accessible to harmful and odorous substances preferably in a proportion of at least 50%, especially between 75 and 80%.

  With regard to the sources of emissions which are cleaned up with the process according to the invention or with the materials according to the invention, these are in particular elements and building materials containing odorous and harmful substances. such as walls, beams, prefabricated partitions, concrete slabs, floors, ceilings, beams, planks and wooden floors, joints, compositions

  and sealing materials and fillers.

  For the purposes of the present invention, the term "harmful substances" is intended to mean, in particular, harmful substances adsorbed on powdered activated carbon, globules of activated carbon, granules of activated charcoal, activated and activated carbon exchangers, particulate charcoal pitch spherical, hydrophobic molecular sieves, bodies molded from hydrophobic molecular sieves or porous polymers. These substances include polychlorinated phenols (PCPs), polychlorinated biphenyls (PCBs), chlorinated hydrocarbons (HCX), polycondensed aromatic compounds (PPAs),

  chlorinated paraffins, phthalates, amines, 2-

  ethylhexanol, ammonia and radon.

Example 1

  The interior partitions of a prefabricated building, which had been contaminated with PCB-containing ambient air for many years, were coated on their entire surface with a heavy wallpaper dispersion adhesive. A flat filter was embedded in the adhesive layer according to EP-A-118 618, formed of a glass fabric which had been loaded on one side with 210 g / m 2 of activated carbon globules of a diameter of 0.5 mm using a spot-printed glue which had been covered with a polyester fleece. After conducting these operations, the PCB content of about 10,000 ng / m 3 of ambient air decreased to less than 300 ng / m 3, and thereafter remained below this value. The matter of

  cover gave the impression of a textile covering.

Example 2

  The material containing adsorbent particles which could be used in the process according to the invention consisted of anti-noise plates which had been loaded on the side facing the partition with active carbon granules having a diameter of 0.5 to 1. , 2 mm, whose application weight was 190 g / m2. Other operations

  of the process were the same as in the previous example.

  By covering the entire surface, we could lower

  also the PCB content to less than 300 ng / m3.

Example 3

  A carpet was used as cover material, the back of which had been loaded with active carbon globules and which completely covered a concrete floor contaminated with PCB. The release of PCBs was then totally prevented.

Example 4

  A polyester fabric web having a basis weight of about 100 g / m 2, to which about g / m 2 of spherical carbon was adhered (average diameter of 0.55 mm), was cut into strips which covered with about 1.5 cm on both sides the joints to be protected. The strips were fixed with adhesive tapes, after which a wallpaper was applied according to Example 1, which was loaded with 200 g / m 2 of spherical carbon particles.

Example 5

  Silicone protective paper was divided into three parts on a 10 cm adhesive tape: in a strip 7 cm wide and on the left and right of it in a strip 1.5 cm wide (1 cm). , 5 cm + 7.0 cm + 1.5 cm = cm). The middle strip of protective paper was progressively removed at the same time as spherical carbon of Example 4, which adhered correctly in the field, was spread on the glue layer. The strip coated with spherical particles of coal could be rolled up without difficulty. At the point of use, the side protective papers were detached and the strip was put in place so that the layer of coal covered the joint by about 1.5 cm. The wallpaper was placed on top

these bands as in Example 4.

Example 6

  A 1 cm thick sheet of crosslinked polyurethane foam, with large pore diameters (weight per liter 30 g, porosity 15 ppi) was in all respects provided with an adhesive composition ("Impranil" HS 62 + "Imprafix "HSC, 30 g / l). Then 200 g of spherical carbon per liter of foam were charged to a shaker. After removal of the excess and thermal curing of the adhesive composition, the sheet was cut into 4.5 cm wide strips which were then pressed into the joints with a width of about 4 cm. The strips were immobilized with adhesive tape as a fastener. These strips were covered with paper

  painted as in Examples 4 and 5.

Example 7

  The same polyurethane foam that was used in Example 6 was provided with a paste of ground activated carbon, water and a dispersion of binders and was stripped of excess on a press. After drying the sheet, the sheet was cut into strips which were then treated as in Example 6. The following is a representative example of the composition of the paste: Activated carbon 315 g (dry basis) Water 435 g Acrylate binder A (soft) 40 g Acrylate binder B (hard) 80 g Thickening agent solution (4% 100 g in water) Lubricant (polyamide based) 15 g The processes according to the invention indicated in Examples 4 to 7 have been used to sanitize PCB contaminated sealing materials in panel constructions. In these examples, after the application of the process according to the invention, PCBs could not be detected on the outer side of the covering liner. Similar tests at the laboratory scale have shown that moisture-insensitive molecular sieves can also be used instead of coal

  active as described in the examples.

  As demonstrated in the examples below,

  above, emissions of harmful substances such as, for example, PCB, could be very strongly repressed and even totally inhibited by the process according to the invention. Compared to the passive collectors according to the prior art, the process according to the invention achieves a direct adsorption of almost 100% of the harmful substances that diffuse from the emission source. The harmful substances of high point

  boiling water, in particular, are then permanently fixed.

  Tests carried out by the Applicant have shown that toxic substances are stably adsorbed to an amount of 10% by weight relative to the adsorbent particles. A coal quantity of 200 g / m 2 can therefore permanently neutralize up to 20 g / m 2 of harmful substances. Since such quantities never appear in practice, activated carbon

is never exhausted.

Claims (42)

  A method for combating emissions of odorous and noxious substances, characterized in that the emission source is directly coated with a material which contains adsorbent particles. Method according to Claim 1, characterized in that the elements or objects contiguous to the emission sources are furthermore covered over a large surface of materials which contain particles. adsorbent.   Process according to claim 1 or 2, characterized in that the material containing the adsorbent particles is selected from the group consisting of open pore foams, nonwoven fabrics and inorganic binders. or organic.   Process according to Claim 3, characterized in that the material is an open pore foam 0.5-5.0 mm thick, preferably a cross-linked polyurethane foam, which contains particles   finely ground adsorbents and a binder.   5. A method according to claim 3, characterized in that the material is a fiber web of 0.1 to 2.0 mm thick which contains particles   finely ground adsorbents and a binder.   6. Process according to claim 3, characterized in that the material is a paint, a coating, a sound-absorbing coating or a whitewash which contains adsorbent particles.   7. A method according to claim 3, characterized in that the material is a carpet containing adsorbent particles, in particular a coating of under carpets.   8. Method according to one of claims 3 to   7, characterized in that the material contains up to 70% in weight of adsorbent particles.   9. A method according to claim 1 or 2, characterized in that the material containing the adsorbent particles is a support layer made of a flat material group of paper, wallpapers or flat planes such as fabrics, knits, sails fibers or fabrics of glass fibers and in that the adsorbent particles   are applied on this support layer.   Process according to Claim 2, characterized in that the carrier layer carrying the deposited adsorbent particles forms a test strip which is deposited on the material containing the adsorbent particles to detect passages of substances toxic for the environment through stopping layers or for   detect the release of such substances.   11. The method of claim 1 or 2, characterized in that the material containing adsorbent particles is a composite material which consists of a support layer made of a plane material of the group of paper, wallpapers or textile plan bodies such as fabrics, fiber webs or fiberglass fabrics, a layer containing the adsorbent particles, located thereon.   support layer and carrying a cover layer.   12. Process according to one of Claims 9 to   11, characterized in that the adsorbent particles are applied to the support layer by means of an adhesive material. Process according to Claim 12, characterized in that the adhesive material is a dispersion of synthetic material, a poor two-component system.   in solvent or a latex, for example natural latex.   14. The method of claim 12 or 13, characterized in that the adhesive material is applied in spots. 15. Process according to claim 12 or 13, characterized in that the adhesive material is a layer   permeable to water vapor, covering the entire surface.   16. Process according to one of Claims 9 to   characterized in that the layer of material (support or cover layer) opposite to the emission source is formed as a water vapor permeable barrier layer.   17. Process according to one of Claims 9 to   characterized in that an additional vapor permeable barrier layer is disposed on the material side (support layer or cover layer) opposite to the source of emission.   18. Process according to claim 16 or 17, characterized in that the barrier layer is the material   adhesive for the adsorbent particles.   19. Process according to one of the claims 16   at 18, characterized in that the barrier layer is constituted by a sheet provided with slits lined on the inner side of the outer layer, in particular a slotted sheet bearing a fuse adhesive, which is bonded to the other side to the adsorbent particles.   20. Process according to one of claims 16   at 18, characterized in that the barrier layer is a latex coating, in particular a latex paint which is applied   on the outside facing the room.   21. Process according to one of the claims 11   at 20, characterized in that the covering layer is made of a plane support material of the paper group, wallpapers or textile planar bodies, such as fabrics, knits, fiber webs or fiberglass fabrics. 22. A method according to claim 21, characterized in that the cover layer is applied in lining by points of fuse adhesive or with a band carrying a fuse adhesive on the material containing the adsorbent particles.   23. Process according to one of Claims 9 to   22, characterized in that the side of the composite material (support layer or cover layer) facing the emission source is a separation layer which allows the composite material to be moved away from the emission source and decontaminate it . 24. A method according to claim 23, characterized in that the separation layer is a divisible paper, a divisible web or consists of two   fiber sails easy to separate.   25. Process according to one of the claims   characterized in that the adsorbent particles are activated charcoal, activated carbon globules, activated carbon granules, carbonized and activated ionic exchangers, pitch-based charcoal spherical particles, hydrophobic molecular sieves, elements molded into hydrophobic molecular sieves or porous polymers. 26. Process according to claim 25, characterized in that the activated carbon has a surface specific of at least 900 m2 / g.   27. The method of claim 25 or 26, characterized in that the globules or granules of activated carbon have a diameter of 0.1 to 2.0 mm, preferably 0.3 at 1.0 mm.   28. Process according to one of the claims   characterized in that the adsorbent particles are impregnated in particular with phosphoric acid,   potassium carbonate, trimethanolamine, 2-amino-1,3-   propanediol, sulfur or copper salts.   29. Process according to one of the claims   characterized in that the adsorbent particles are present in an amount of 5 to 400 g / m 2, preferably 10 to 250 g / m 2   Process according to one of the claims   preceding, characterized in that the materials containing the adsorbent particles are in the form of strips which are arranged on joints sealed with sealing materials containing harmful substances and are embedded in these joints.   31. Process according to one of Claims 9 to   , characterized in that the surface of the adsorbent particles is freely accessible in a proportion of at least%, especially between 75 and 80%, to harmful and odorous substances.   32. Process according to one of the preceding claims, characterized in that the emission sources   are building elements or materials containing odorous and noxious substances, such as walls, beams, prefabricated partitions, concrete slabs, floors, ceilings, beams, wooden planks and floors, joints , compositions and sealing materials, putty fillers.   33. Process according to one of the claims   preceding, characterized in that the harmful substances contained in the emission source can be adsorbed by the adsorbent particles.   34. Process according to claim 33, characterized in that the harmful substances are polychlorinated phenols (PCP), polychlorinated biphenyls (PCB), chlorinated hydrocarbons (HCX), polycondensed aromatic compounds (ARP), chloroparaffins, phthalates ,   amines, 2-ethylhexanol, ammonia or radon.   35. Adsorbent material, containing a planar support material which is formed as a water vapor permeable barrier layer, and a layer on the barrier layer   and containing adsorbent particles.   36. An adsorbent material containing a planar support material, an additional vapor-permeable barrier layer disposed on the support material, and a layer disposed on the barrier layer and containing adsorbent particles.   37. Adsorbent material according to claim, characterized in that it contains an additional cover layer disposed on the layer containing the adsorbent particles. 38. Adsorbent material according to claim 36, characterized in that it contains an additional covering layer disposed on the layer containing the adsorbent particles.   39. Adsorbent material according to one of the   Claims 35 to 38, characterized in that the material of   planar support belongs to the group of paper, wallpapers or flat textile bodies such as fabrics, knits,   fiber sails or fiberglass fabrics.   40. Adsorbent material according to one of the   Claims 35 to 39, characterized in that the layer   stopping is the adhesive material for the adsorbent particles. 41. Adsorbent material according to one of the   Claims 35 to 40, characterized in that the layer   stopper is constituted by a sheet having slots, applied in lining on the inner face of the outer layer, in particular a slot sheet carrying a fuse adhesive, which is bonded to the other side to the particles adsorbent.   42. Adsorbent material according to one of the   Claims 35 to 41, characterized in that the layer   stopping is a latex coating, including a latex paint, which is applied on the outer side facing the piece.   43. Adsorbent material according to one of the   Claims 35 to 42, characterized in that the particles   adsorbents are activated charcoal, activated carbon globules, activated carbon granules, carbonized and activated ion exchangers, spherical pitch coal, hydrophobic molecular sieves, molded molecular sieve elements   hydrophobic and / or porous polymers.   44. Adsorbent material according to Claim 43, characterized in that the activated carbon has a surface specific of at least 900 m2 / g.   45. Adsorbent material according to Claim 43 or 44, characterized in that the globules or granules of activated carbon have a diameter of 0.1 to 2.0 mm, preferably from 0.3 to 1.0 mm.   46. Adsorbent material according to one of the   Claims 43 to 45, characterized in that the particles   adsorbents are impregnated in particular with phosphoric acid,   of potassium carbonate, trimethanolamine, 2-amino   1,3-propanediol, sulfur or copper salts.   47. Adsorbent material according to one of the   Claims 43 to 46, characterized in that the particles   adsorbents are present in an amount of 5 to 400 g / m2, preferably from 10 to 250 g / m2.   48. Adsorbent material according to one of the   Claims 37 to 47, characterized in that the layer of   blanket is a flat support material of the group of paper, wallpapers or flat planes such as fabrics, knits, fiber sails or fiber fabrics of glass.   49. Adsorbent material according to one of the   Claims 37 to 48, characterized in that the layer of   cover is applied in lining by fusible adhesive dots or using plies wearing a fuse adhesive on   the material containing the adsorbent particles.   50. Adsorbent material according to one of   Claims 35 to 49, characterized in that its side turned   to the emission source (support or cover layer) is a separation layer that allows the adsorbent material to be removed from the emission source and its decontamination.   51. Adsorbent material according to claim, characterized in that the separating layer is a divisible paper, a divisible web or consists of two webs of easily separable fibers.