NO300426B1 - Procedure for eco-friendly removal of oil and oil-like substances from the water or soil surface and oil adsorbents applicable thereto - Google Patents

Abstract

To combat oil spillages and for rapid uptake of the escaped oil or oleaginous substances, there serves a process in which high-temperature-blown glass wool is hydrophobised and simultaneously bound using silicone and a starch serving as binder. The glass wool treated in accordance with this is then combined to form a cuttable, mat-shaped framework and is expediently dried at 150 DEG C. The then cohering three-dimensional framework mats are applied to the contaminated water sites and are left there for complete absorption, and are then together with the absorbed oil, subjected to intermediate storage and then mechanically or thermally disposed of or reprocessed. A corresponding adsorber is composed of this fine-fibre glass wool which is prepared and configured by coating with silicone and starch in such a way that adsorption of the oil away from the water surface or the ground surface is then possible. <IMAGE>

Description

The present invention relates to a method for avoiding and/or helping the contamination of water and soil with oil or oil-like substances by applying hydrophobic, inorganic fibers to the exposed area, binding the threatening oil to the fibers and treatment by separating fibers and oil. The invention also relates to an oil adsorber for absorbing oil or oil-like substances from the water or soil surface, comprising inorganic fibers equipped with silicone as a hydrophobic agent.

With the ever-larger oil transports, the threat to the environment due to oil leaks is also increasing. Within the framework of the oil disaster of recent years, entire stretches of coast have been heavily polluted and marine life has been totally destroyed in the exposed areas. There has been no lack of attempts to pump up leaked oil from the surface of the water or soil, or to neutralize it by spraying various substances onto the oil or oil-like substances. From FR-PS 2,646,189 it is known to blow hydrophobized mineral fibers on the surface of the water where these fibers bind oil or oil-like substances to them and capture these to then lift off the mixture and further process it. The fibers, which must be relatively short, are hydrophobicized with a silicone oil. The amount of addition is at 0.5 to 3 weight-#. A shortcoming of this known method is that the relatively short mineral fibers tend to sink when they cannot form a bond with the oil in time. Thereby, a part of the blown-out mineral fiber materials is lost before they become active at all. The pollution of the seabed and also the earth is thus quite significant.

FR-PS 2,401,214 also describes the absorption of oil by means of mineral fibers whereby these mineral fibers are pre-impregnated by means of a binder. This method exhibits deficiencies comparable to those described for FR-PS 2,646,189.

From GB-PS 1,235,463, a method is known in which the oil lying on water is to be taken up by means of inorganic fibres, whereby the fibers are equipped in advance with a water-repellent material. The fibers float on the water and lead to a deposit of oil which is then removed by burning the fibres. Apart from the fact that simply burning off the oil taken up by the fibers cannot generally be defended purely economically, there is also a significant environmental impact due to the burning of the oil. In addition to this, it has been shown that the absorption capacity of fibers laid out or blown onto the surface of the water is not sufficient to absorb the sufficient quantities of oil within a short time and to hold it safely. In addition, the recovery of the fibers filled with added clay is rather complicated, whereby the above-mentioned effect also occurs here, namely that part of the fibers sink into the water or cannot be recovered for other reasons.

The present invention therefore has the task of providing a quick and safe-acting method to combat tanker accidents and similar problems as well as to provide a suitable oil adsorber with the help of which an overall environmentally friendly handling of leaked oil or oil-like substances is possible.

According to the invention, this task is solved by blowing glass wool in the high-temperature area being hydrophobized and at the same time bound with silicone and a starch (polysaccharides) serving as a binder, the glass wool thus treated being transferred to a cutable, mat-like grid before or during drying at 150°C and continuously applied to the stressed water or soil surface and left there until full absorption, after which the largely fully absorbed glass wool is taken up and temporarily stored and then subjected to a mechanical or thermal separation.

With such a method, it is possible, also in the event of a major ship accident or other environmental stress, within a short time to lay on a glass wool mat suitable for adsorption or several similar mats, to capture leaked oil or oil-like substances, to bind these and to transport them away. The combined "coating" of the individual glass wool threads ensures that in the end the individual threads do not just lie loosely on top of each other but, on the contrary, provides an advantageous grid that can absorb a large amount of oil and similar "damages". In addition, this lattice work offers the possibility to really bind the once occupied substances in such a way that the mats can be recovered and temporarily stored until the final processing can begin. This final treatment can be carried out mechanically and/or thermally, depending on whether or not you want to use the glass wool or the corresponding glass wool grid mats again. During the "combustion" of the glass wool at approx. At 150°C, not only is the drying effect accelerated, but there is also a certain reaction in the silicone/starch mixture with the individual fibres. The starch enables a certain joining or gluing of the individual fibers so that the described lattice work can be achieved, which in turn gives the mat the necessary stability but also in another way enables the deposition of the oil or the oil-like substances. The corresponding mats make up a spatial lattice structure which, via capillary action, ensures oil adsorption.

An advantageous spatial lattice work is achieved in particular by adding 7 to 10 # of silicone and starch to the wool so that the individual glass threads obtain the necessary stability or preserve this, above all also their length, so that the described favorable lattice work is ensured.

The mixture of silicon and starch achieves the sufficient adhesive effect when the mixture is in the ratio of 94 to 96% silicone per 6 to 4 # starch and when this is then simultaneously added to the glass wool. It thus turns out that during the subsequent drying, a hardening takes place which means that the latticework retains the large surface which can then absorb the corresponding amounts of oil.

In order to ensure the most even possible coating of the individual glass fibres, the invention aims for silicone and starch to be applied to the fibers or fiber strands before or at the joining of the fibres. Thereby, practically every single fiber is reached so that these can be taken to further processing in a correspondingly pre-treated manner. It is also advantageous that the fibers are sprayed in such a way that practically no droplets are formed, thereby in turn ensuring an even coating of the individual fibers and a corresponding laying of the fibers. Above, it is described that a shearable, mat-shaped lattice work is provided which is then maximally suitable for adsorption of oil. In order to achieve the greatest possible surface and also in a way a large cavity around the individual fibers, the invention aims for the sprayed fibers to be laid on top of each other and then compacted and then joined at approx. 150°C. This results in a loose but still easily cuttable and advantageous latticework.

If you want to achieve a higher raw density, you have the option that after spraying with silicone and starch, the fibers can be brought together under force and then fused, whereby this forced movement is already sufficient to achieve the light compression.

A large surface on the one hand and yet a great stability on the other hand is achieved with such a grid when soft glass wool with a fiber diameter of 5 to 7 pm is used as glass wool. This fine glass wool can also be stabilized to such an extent that the required fiber length is achieved and can be maintained, whereby overall a uniform lattice work is achieved which is suitable for absorbing large quantities of oil. It is surprising that this thus created latticework exhibits a recording capacity of 1:30. 1 liter of the soft glass wool with a weight of approx. 30 g binds 900 g of oil. The oil-soaked fiberglass mat in this way can be further processed in various ways. One can imagine that the glass wool grid mat saturated with oil or oil-like substances to an extensive extent is freed from oil by pyrolysis or direct annealing at approx. 850°C. Thereby, the glass turns into a melt and can be advantageously used, for example, in road construction applications, as it is completely free of oil residues.

A further method is to centrifuge or compress the glass wool grid mat that is extensively saturated with oil or oil-like substances. This treatment has the advantage that, in principle, you keep the glass wool grid mats and can possibly use them again. Here it does not matter that the oil is not removed 100% from the mat but, for example, only in an amount of 99%. A further advantage is that the oil is then available in a processable form, whereby it also depends on what stage it was in at the moment it was released into the environment. When centrifuging, it can therefore be advantageous to set the centrifugation force so that the stability of the glass wool grid mats is taken into account so that these are maintained in a usable condition.

Where you have at your disposal an oil incineration plant whose operation is frequently supplemented with supplementary fuel, it is advantageous when the glass wool grid mats are added to the waste incineration where they are also submitted to landfill. The oil is burned, whereby the solid residues go into the ash together with the solid residues of the glass wool grid mats, while the other residues are carried out with the flue gases and taken care of together with them.

The spread of an oil blanket is advantageously prevented by pushing the glass wool grid mats into a perforated hose and laying them out with these as a variable barrier on the water surface. Through the perforations, the oil has access to the glass wool grid mat so that it can absorb the oil. The hose itself can be made of a material that does not represent any environmental risk or is not affected by harmful substances. The glass wool mesh mats gradually become full so that a certain sinking of the hose with the glass wool mesh mats occurs so that new zones of the mats come into contact with the oil and can also absorb it. The oil itself, however, provides a natural buoyancy so that the hose does not sink overall. Once the oil coating has been removed by applying additional glass wool grid mats, the hose or the hose barrier can also be removed and treated. Here, too, one can imagine that the oil can be driven out by compression or centrifugation in such a way that the barrier can then be used once more. The enormous absorption capacity for the barrier and also the imposed mat elements guarantees an immediate tearing up of the closed oil blanket with the result that at least part of the necessary oxygen supply can be resumed. However, the island-like oil patches that may still remain ensure the maintenance of life of all kinds below the water surface, so that this already has a gentle effect at an early stage. However, it is also conceivable to place an oil adsorber as a permanent device around drilling devices so that any partially released oil layers can be captured without there being any danger of them escaping via the water surface. The use of such glass wool grid mats in perforated hoses is also advantageous because the risk of explosion is reduced or avoided by early absorption of the oil.

Oil adsorbers of the type of the invention have not been known until now. According to the known technique such as FR-PS 2,646,189, hydrophobic inorganic fibers are everywhere only scattered over the water without giving them any stable skeleton or latticework, which only now justifies the designation oil adsorber. In order to obtain such an oil adsorber that can be used in the method of the invention, the invention aims at coating the glass fibers obtained in the high temperature range with a mixture of silicone and starch (polysaccharides), that the fibers are brought together into cutable, mat-shaped glass wool strands and then hardened and deposited. This provides spatially formed oil adsorbers which, depending on the dimensions, i.e. thickness and length as well as depth, can absorb practically any amount of oil. Thereby, the oil transported due to the capillary action can be stored in the grid in such a way that it is not pushed out again even under small loads, for example when the mats are removed from the water. Naturally, the fixation of the oil depends on the pourability of the oil, but it should be said that oils as such are always safely taken up, while gasoline and similar substances can only be bound in to a certain extent, that the mats can then also be transported and temporarily stored and finally further processed. It is also important that the oil can be absorbed to such an extent that it can be fixed securely to the individual glass fibers with their large surfaces. This is ensured by the grating provided according to the invention.

The oil adsorbers of the invention are particularly suitable for use in the form of barriers when the glass wool grid mats are surrounded by a perforated hose. Thereby, these glass wool grid mats are usually pushed into the hose. However, one can also think of forming the hose from corresponding foil with corresponding perforations and then wrapping the foil around the individual glass wool grid mats with subsequent welding so that manual work can be avoided to a large extent. Glass wool grid mats also perform their function as an oil adsorber in the perforated hose, whereby, however, it is also securely retained in the perforated hose and secured against impact and damage.

Sufficient absorption capacity on the one hand and advantageous stability on the other hand are achieved with a glass wool grid mat which has a room weight of 18 to 42 kg/m 5 .

The adsorption effect of the glass wool grid mats is particularly ensured by the fact that the fibers are placed loosely on top of each other after coating and then joined at 150°C. In this way, a fast and safe acting grid skeleton is achieved, respectively a spatial grid structure which also advantageously and safely stores the trapped oil. Above 150° C, the reaction between the silicone or starch material and the fibers is accelerated and optimized so that the necessary advantageous glass fibers of small diameter are bonded together to the grid.

The invention is particularly distinguished by the fact that it provides a method and an oil adsorber with the help of which environmental hazards can be quickly and safely combated by e.g. tanker accident. The 01jeadsorber, which is produced in the manner described, can be placed as a glass wool grid mat on the surface of the water, whereby it then automatically absorbs oil or oil-like substances and then binds these substances to such an extent that the substances together with the glass wool grid mat can be transported. The glass wool grid mats are then further processed, so that they can either be disposed of in an environmentally friendly way or be put to new use. Surprising is the speed with which the glass wool grid mat picks up the oil or the oil-like products and also fixes this in a safe way, so that a good removal from the exposed areas is achieved and then at a later time to continue and finish the deposition work.

Further details and advantages of the objects of the invention can be found in the following description of the attached drawings, where a preferred embodiment is described. The drawings show: fig. 1 schematically shows a device for the production of

glass fibers,

fig. 2 a single glass fiber in section,

fig. 3 post-processing steps for the procedure sketch i

fig. 1, and

fig. 4 a glass wool grid mat arranged in a hose.

Fig. 1 first shows the glass melt 1 which has been heated in a suitable way. The glass flow 2 exits into the burner area 3 where the rotating centrifuge 4 with the nozzles 5 ensures a corresponding fiber formation. The induction heating is indicated by position 7.

The individual glass fibers 9,10 leave the nozzle part 5 and are then available for further processing as glass wool strand 18.

The further processing of the glass fibers 9,10 and the glass wool strand 18 takes place by spraying silicone and starch, whereby these materials are supplied via supply pipes 12 and 13 in an already mixed state and then brought forward via the free air nozzle 14 and sprayed onto the glass fibers 9,10. The supply pipes 12, 13 are hereby connected via the mixing container 16 with the silicone container 14 and the starch container 15.

While the glass stream 2 is affected by hot air from the hot air supply 6, the air nozzle 17 can be fed with normal air.

Fig. 2 shows a single glass fiber 9,10 which is equipped with a coating 19 of silicone and starch. For clarification, coating 19 is shown on a non-proportional scale.

In fig. 1 it is suggested that the two glass wool strands 18,18' are fed into each other and placed together, while the two glass wool strands 18,18' in fig. 3 are simply added together, which is sufficient to stabilize the fibers or the resulting lattice structure by a corresponding binding effect. This bonding takes place in the method of the invention by adding starch, while the added silicone should hydrophobicize the individual glass fibers 9,10.

By the one in fig. 3 embodiment of the invention, the drying takes place at approx. 150°C via oven heating 20. However, there are also other possibilities for optimizing the thus formed glass wool grid mat 21 in a similar way using heat.

Fig. 4 shows a section of a hose 22 in which a glass wool grid mat 21 is arranged. The hose 22 is equipped with a number of holes arranged along its length and circumference in order in this way to give oil or oil-like substances access to the grid mat through the hose 22 as follows that the glass wool grid mat fully exerts its adsorption effect.

While, in accordance with the above, only adsorbent and binding agent is supplied from one point, it is also conceivable that either silicon or starch or a mixture is sprayed onto the glass wool strands 18 from further mixing points 24,25, so that the last treatment of the relevant glass wool grid mat takes place in the area of the supply pipes 12,13.

All the features mentioned, including those that can be obtained from the drawings alone, are considered part of the invention, both individually and in combination.

Claims (10)

1. Procedure for avoiding or combating contamination of water and soil with oil or oil-like substances by applying hydrophobic, inorganic fibers to the exposed area, fixing the threatening oil on the fibers and processing by separating fibers and oil, characterized in that in the high-temperature area blown glass wool is hydrophobized and at the same time bound with silicone and a starch (polysaccharides) that serves as a binder, that the glass wool treated in this way is transferred to a cuttable, mat-like grid before or during drying at 150°C and continuously applied to the stressed water or soil surface and is left there until fully absorbed, after which the largely fully absorbed glass wool is taken up and temporarily stored before being subjected to a mechanical or thermal separation. 2. Method according to claim 1, characterized in that the glass wool is mixed with 7-10% silicone and starch whereby silicone and starch are mixed in a ratio of 94 to 96% silicone per 6 to 4$ starch and then together applied to the glass wool. 3. Method according to claims 1 and 2, characterized in that silicone and starch are sprayed onto the fibers or the fiber strands before and when laying the fibers, that the sprayed fibers are placed on top of each other and thereby compacted and then processed at approx. 150°C for fixation, using soft glass wool with fiber diameters between 5 and 7 µm as glass wool. 4. Method according to claim 1, characterized in that the glass wool grid mats saturated with oil or oil-like substances to an extensive extent are freed from oil by pyrolysis or direct annealing at 850°C. 5. Method according to claim 1, characterized in that the glass wool grid mats saturated with oil or oil-like substances to an extensive extent are freed from oil by centrifugation or compression. 6. Method according to claim 1, characterized in that the glass wool grid mats are taken to waste incineration. 7. Method according to claim 1, characterized in that the glass wool grid mats are pushed into a perforated hose and together with this are placed on the water surface as a variable barrier. 8. Oil adsorbers for absorbing oil or oil-like substances from the water or soil surface, consisting of inorganic fibers equipped with silicone as a hydrophobic agent, characterized in that the glass fibers obtained in high-temperature areas (9,10) are coated with a mixture of silicone and starch (polysaccharides) (19), that the fibers are brought together into cutable mat-shaped glass wool strands (18) and hardened and then cut to size. 9. Oil adsorber according to claim 8, characterized in that the glass wool grid mats (21) are surrounded by a perforated hose (22). 10. Oil adsorber according to claim 8, characterized in that the glass wool grid mats (21) have a bulk density of 18 to 42 kg/m^, the glass fibers (9,10) being laid loosely on top of each other after coating and then fixed at 150"C.