DE3145547A1 - Mat for absorbing organic liquids, preferably oil, as well process for its production - Google Patents

Abstract

According to the invention, a mat absorbing oil or organic liquids is proposed, the special feature of which is that it has a core of closed-pore foam provided on one or both sides with a nonwoven of synthetic fibres. In this way, a good buoyancy is obtained at the same time as adequate absorptivity for oil or other organic liquids. To produce such a mat, it is envisaged to pin the nonwoven layers onto the foam core and subsequently subject the laminate thus formed to a heat treatment up to the beginning of the thermoplastic range of the foam or the fibres, a calendering treatment also being envisaged.

Description

Mat for absorbing organic liquids, preferably oil, and methods for their production. The invention relates to mats for receiving of organic liquids, in particular liquids distributed in or on water, preferably oil, which as the organic liquid-absorbing element is a synthetic fleece Includes fibers. The term “mat” is also to be understood as meaning a structure which is relatively is thick, but has only a small surface area, for example also in the form of a ribbon or

Strip. The invention also relates to a method for the production of such mats.

It is known to suck up oil or other organic liquids, especially when the se are distributed in or on water, mats or balls to use nonwovens made of synthetic fibers. Such fleeces are, even when they are wet, able to contain comparatively high amounts of organic To absorb liquids or oil. Provided wet fleece used the absorbed water is given off due to its oleophilic properties and instead the oil or the oil-like organic liquid to the surface of the fibers of the fleece bound. Based on these properties, it can be presumed Very good results in terms of water pollution, etc., in particular achieve the binding of the oil or the organic liquids So far, one goes in such a way that the fleece is used in web form, as a roll or in the form of full is, the cohesion in rolls or mat form generally by a corresponding wrapping is achieved. Such a procedure has on the one hand the Disadvantage that the mechanical stability may leave something to be desired, because the cover has to be provided with correspondingly large openings and mostly also only provided in the form of a network iSto Another very essential wangel of the known oil-absorbent mats or rollers is that they are only very limited are able to swim, which is especially important when there is oil or the like but should be absorbed by the water surface. As soon as the known ones Mats or the like with oil or the organic liquid and also have soaked up a certain amount of water, ihx becomes specific Weight SO high that they sink below the surface of the water.

So far, they have managed to get them out of the fleece existing, oil-absorbing mats or the like either attached to floating bodies or stretched between ships or other retaining elements by means of ropes became. This of course complicates the use of the known elements and also brings certain restrictions in the possible applications. For example there must always be at least two boats when stretching between ships, which must keep a certain mutual distance. This prepares Especially with heavy swell, there may be considerable difficulties and requires the use of correspondingly strong and therefore heavier ropes, which in turn leads to the fact that the nonwovens absorbing the oil sink below the surface of the water must be expected.

Furthermore, it should be noted with regard to the known mats or the like, that these are relatively difficult to manufacture. Especially when wrapping with a net, this net must generally be attached by hand will.

The invention is based on the object of providing a mat of the initially to propose mentioned type, which is easy to produce on the one hand, but on the other hand good buoyancy with sufficient capacity for oil or the like having. At the same time, a particularly simple method for producing such Mats are specified.

To solve this problem it is proposed according to the invention, a to train generic mat so that it has a closed surface having, no water-absorbing, buoyant core, the at least is covered on one side with a layer of the fleece attached to it.

While it was previously assumed that in order to achieve the greatest possible absorption capacity for oil or the like to achieve the mat made of synthetic fleece throughout Should there be Fassern, is therefore proposed according to the invention, only to provide a fleece outer layer, while the core of the mat is made of buoyant, there is no water-absorbing material. By using such a core the specific weight of the mat can be kept so low that it is under all Is perfectly buoyant under conditions. It is of course essential that the core has a closed surface, so it cannot soak up. Despite the presence of such a core, however, it is always possible without further ado still achieve a sufficient capacity for oil or organic liquids, which is probably due to the fact that the deposition of the oil or the organic Liquids generally only occur in the outer layers of the fleece anyway, because when they are loaded with oil or the like, further penetration into the interior the mats in the known mats only takes place very slowly. So it's that Effectiveness of the fleece or the mat according to the invention for loading work absolutely 4) comparable to the absorption capacity of known mats.

Only when the mat stays in the water for a longer period can the known mats may absorb a little more oil, provided that they are used accordingly are secured against sinking below the water surface, but the above explain difficulties arise.

After the mat according to the invention on the water surface always floats, it can be easily removed and removed to remove the oil or the organic Liquid can be expressed, whereupon it is immediately ready for use again.

The fleece can enclose the core on one side or on all sides. in the In general, the training will be chosen so that the core is on both sides of the Fleece is covered from synthetic fibers.

In order to achieve a sufficient buoyancy of the mat, should According to the invention, the specific weight of the core can be so low that it is in Water has a buoyancy force of at least 5 N, preferably about 10 N, per liter of the core volume.

The core can consist of various materials.

However, for the sake of ease of manufacture and handling, it is particularly favorable when the core consists of closed-cell foam. A such a material combines good strength with excellent buoyancy and can easily be made to any thickness and density desired.

To fix the fleece on the foam core, the known Procedures are used, for example wise a chemical or thermal bonding. However, it is particularly favorable if the fleece with the foam core connected by needling, because then solidification in one operation of the fleece and at the same time its fixation on the foam core can. Another possibility is of course to use the fibrous web forming the fleece To mix in binding fibers so that the fleece can be fixed by heat. One Another possibility for the formation of a fleece from the fibrous web is to use liquid To use binding agent, in which case the fiber pile additionally by an application device must be performed for the binder. Of course, a fleece can also be used be used, which on the one hand by heat or a binder and on the other hand by a needling process, for example during the fixing on the foam core, is fixed.

The foam core can be made of different materials, for example Polyurethane, polyester, etc. exist, provided it is only closed-cell. It has However, it has been found that a foam core is particularly advantageous which made of polyethylene.

Another way of training the mat is that of The core is formed by a bubble wrap onto which the fleece is applied in a custom-made chopping process is glued on. One will choose this training before anything, if only one-sided a layer is provided.

In principle, all synthetic materials can be used to produce the fleece Fibers are used. However, polyolefin fibers are particularly suitable, for example Polypropylene or polyethylene fibers, because then they have sufficient absorption capacity for oil is achieved.

It is also important that the effective specific surface area of the Fleece, especially if it is only used in comparatively thin layers, if possible is high. For this reason, the titer of the fibers should of the fleece below 20 dtex, preferably below 17 dtex. In contrast, the stack length is and basically the cross-sectional shape of the fibers is of secondary importance. In practice, all fibers can be used for the fleece; dealing with the can be processed by conventional textile machines.

A particularly high absorption capacity for oil or other organic ones Liquids can be reached if the fleece is made of polypropylene splice fibers with a high specific surface. Such fibers can be particularly beneficial accumulate a lot of organic liquid. The specification of the titer or the fiber length is hardly possible with such splice fibers, since they are generally not with constant Titer or uniform fiber length come on the market.

Depending on the respective area of application, the core can be different Have thickness. According to the invention it is provided that the core has a thickness of 2 to 5Q mmhat.

In the same way, the thickness of the core on one or all sides applied fleece. According to the invention it is provided that the fleece on the core as a layer with a basis weight between about 20 and 1,500 g / m², preferably between 50 and 300 g / m² applied. This is how you usually get mats with a basis weight between about 160 and 2,000 g / m². From what core thickness or which fleece thickness you start from depends, as already mentioned from the later use. If only thin oil films are to be removed, use is sufficient a fleece with a basis weight of 50 g / m2 on each side of the core. Should On the other hand, large quantities of oil are absorbed, it is better to add one per side of the kernel Provide fleece with a weight per unit area of 300 g / m2. The thickness must also be similar of the core serving as the buoyancy body are each specially selected. To rule high flow velocities or strong waves, it will be useful to use a core with a thickness of about 40 to 50 mm. In standing water on the other hand, at the lower limit of the range claimed according to the invention, i.e. at about 2mm thickness for the core.

As mentioned above, there are several ways that Manufacture mats according to the invention. In the event that there is a connection between Fleece and a foam core should be done by needling, after the Invention proposed a method which consists in that the fleece corresponding Basis weight is needled on one or both sides of the foam core and that then the layer structure of fleece layer (s) forming the mat and foam core until the beginning of the thermoplastic softening of the fleece forming fibers and / or the foam forming the core heated and one Is subjected to calender treatment.

Such a procedure has the advantage that on the one hand the application and fixing the fleece on the foam core very easily and by means of the usual Maschlnerl can be done. By heating the layer structure forming the mat to a temperature in the range of the thermoplastic softening of either of the fibers or the foam there is also an additional definition of the Foam pricked fibers of the fleece in the foam. Achieved this way one that the one-sided or two-sided fleece layer is particularly good on the foam core adheres, whereby the adhesion is of course particularly good when correspondingly with each other compatible materials are used and the heating is carried out to a temperature where both the fibers and the foam are somewhat soft in this process However, care must be taken that the warming is not too strong otherwise the foam core could collapse or fuse of the fibers of the fleece would be feared, whereby each of the desired properties the mat could be seriously affected. In the event of a coincidence of the foam core would reduce its buoyancy. With a merging the barrels forming the fleece would reduce the capacity for organic liquids impaired.

A particularly firm anchoring of the pierced fibers of the fleece in the foam core is achieved when the layer structure forming the mat is cooled abruptly after exiting the calender0 Below some examples of the formation of mats are dependent on the invention specified by the intended use, whereby a foam core is provided in each case: (1) Small accidents often occur in inland areas in which there is only a thin one oil film results. For such minor accidents on inland waters with weak currents a foam core of 5 mm thickness is sufficient, which on each side with a Fleece is needled with a basis weight of 100 g / ml. The mat then has one Total thickness of about 12 mm.

(2) Should be a thicker film to eliminate when the current is weak a mat with a higher oil binding capacity must be used. Here you go from a foam core, also 5 mm thick, with a Fleece layer is provided with a weight per unit area of about 300 g / m3. Reached the mat then a total thickness of 20 mm. Compared to example (1) is the oil absorbency clearly improved.

(3) For bodies of water with stronger currents, a thicker foam core must be used 15 mm thick, for example, can be used. If you cover this foam core on both sides with a fleece layer with a weight per unit area of 200 g / m2 is achieved a medium oil binding capacity.

The total thickness of the mat is then approx. 25 mm.

(4) For rivers with strong currents, e.g. mountain rivers, or for use in the sea, a float must be used, which is also the case with high waves guarantee perfect swimming. For such cases For example, a foam core with a thickness of 40 mm can be used is needled on both sides with a fleece with a weight per unit area of 200 g / m². the A mat constructed in this way has an oil-binding capacity which is sufficient for most applications and a thickness of approx. 50 mm.

Claims (14)

Claims: 1. Mat for the absorption of organic, in or on water dispersed liquids, preferably oil, which as the organic liquid the receiving element comprises a fleece made of synthetic fibers, characterized in that that they have a closed surface, no water absorbing, buoyant Has core which at least on one side with a layer of the fleece attached to it is covered. 2. Mat according to claim 1, characterized in that the core on all sides is covered with the fleece 3. Mat according to claim 1 or 2, characterized in that that the specific gravity of the core is so low that it can be immersed in water ser generates a driving force of at least 5 N per liter of the core volume. 4. Mat according to one of the preceding claims, characterized in that that the core consists of closed-cell foam. 5. Mat according to claim 4, characterized in that the fleece with the foam core is connected by needling. 6. Mat according to claim 4 or 5, characterized in that the Foam core is made of polyethylene. 7. Mat according to one of claims 1 to 3, characterized in that that the core is formed by a bubble film on which the fleece in a Laminating process is glued on. 8. Mat according to one of the preceding claims, characterized in that that the fleece consists of polyolein fibers (polypropylene or polyethylene fibers). 9. Mat according to one of the preceding claims, characterized in that that the titer of the fibers of the fleece is below -20 dtex, preferably below 17 dtex, lies. 10. Mat according to one of the preceding claims, characterized in that that the fleece is made of polypropylene splice fibers with a high specific surface consists. 11. Mat according to one of the preceding claims, characterized in that that the core has a thickness of about 2 to 50 µm 12. Mat according to one of the preceding Claims characterized in that the fleece on the core as a layer with a weight per unit area between about 20 and 1,500 g / m², preferably 50 and 300 g / m², is applied. 13. A method for producing a mat according to any one of the claims 4 to 6, characterized in that the fleece has a corresponding weight per unit area is needled on one or both sides of the foam core and that afterwards the layer structure of the nonwoven layer (s) and foam core forming the mat at the beginning of the thermoplastic softening of the fibers forming the fleece and / or of the foam forming the core is heated and subjected to a calendar treatment will. 14. The method according to claim 13, characterized in that the After exiting the kala, the layered structure forms mats and cools down suddenly will