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Title:
BRUSH FOR COLLECTING OIL FROM WATER USING A COLLECTION DEVICE AND A CORRESPONDING COLLECTION DEVICE
Document Type and Number:
WIPO Patent Application WO/2017/212117
Kind Code:
A1
Abstract:
The invention relates to a brush for collecting oil from water using a collection device, which brush (10) includes - a body (12) arranged to form a circle (14) arranged to be supported around the rotation shaft (104) of a collection device (100), which body (12) includes an outer surface (24), - bristle bunches (22), comprising several individual brush fibres (20) attached to the said outer surface (24) to collect oil, each of which brush fibre has two ends, i.e. a base end (44) and a free end (48), which bristle bunches (22) include first bristle bunches (25) and second bristle bunches (28), of which the second bristle bunches (28) are greater in length between the free end (48) of the brush fibres (20) and the outer surface (24) of the body (12) than the first bristle bunches (25), which said bristle bunches (22) form a continuous brush surface (26) on the brush (10). In the said second bristle bunches (28) the brush fibres (20) are bent over a selected length in a selected direction, which direction differs from the direction of the brush fibre (20) over the rest of the length of the brush fibre (20) and which selected length is greater than the length of the first bristle bunches (25) from the outer surface (24) of the body. The invention also relates to a corresponding collection device.

Inventors:
SAJAKORPI, Kimmo (Kolsopintie 6, YLÖJÄRVI, 33470, FI)
HIRSIVUORI, Timo (Kolsopintie 6, YLÖJÄRVI, 33470, FI)
Application Number:
FI2017/050423
Publication Date:
December 14, 2017
Filing Date:
June 07, 2017
Export Citation:
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Assignee:
SAJAKORPI OY (Kolsopintie 6, YLÖJÄRVI, 33470, FI)
International Classes:
E02B15/10; A46B9/02; E02B15/04
Domestic Patent References:
2007-06-28
1997-10-23
Foreign References:
FI107280B2001-06-29
Attorney, Agent or Firm:
KESPAT OY (Vasarakatu 1, JYVÄSKYLÄ, 40320, FI)
Download PDF:
Claims:
CLAIMS

1. Brush for collecting oil using a collection device, which brush (10) includes

- a body (12) arranged to form a circle (14) arranged to be supported around a rotation shaft (104) of the collection device (100), which body (12) includes an outer surface (24) ,

- bristle bunches (22), comprising several individual brush fibres (20) attached to the said outer surface (24) to collect oil, each of which brush fibre has two ends, i.e. a base end (44) and a free end (48), which bristle bunches (22) include first bristle bunches (25) and second bristle bunches (28), of which the second bristle bunches (28) are greater in length between the free end (48) of the brush fibres (20) and the outer surface (24) of the body (12) than the first bristle bunches (25), which said bristle bunches (22) form a continuous brush surface (26) on the brush (10) , characterized in that in the said second bristle bunches (28) the brush fibres (20) are bent over a selected length in a selected direction, which direction differs from direction of the brush fibre (20) over rest of the length of the brush fibre (20) and which selected length is greater than the length of the first bristle bunches (25) from the outer surface (24) of the body.

2. Brush according to Claim 1, characteri zed in that the said second bristle bunches (28) are 1.5 - 3 times, preferably 2.0 - 2.5 times the length of the first bristle bunches (25) . 3. Brush according to Claim 1 or 2, characteri zed in that in the said second bristle bunches (28) the brush fibres (20) are bent at an angle of 40 - 90° relative to the longitudinal direction of the first bristle bunches (25) in order to form a trough-like structure (30) against the brush surface (26) to collect oil.

4. Brush according to any of Claims 1 - 3, characteri zed in that the body (12) is one of the following: a brush drum, a brush belt, or a chain consisting of body elements (32) .

5. Brush according to any of Claims 1 - 4, characteri zed in that the ratio of the second bristle bunches (28) to the first bristle bunches (25), and the length of the portion of the second bristle bunches (28) bent in the direction of the circumference of the brush (10) are arranged to be such that a gap for oil remains between the consecutive second bristle bunches (28) in the direction of rotation of the brush (10) .

6. Brush according to any of Claims 1 - 5, characterized in that in the said second bristle bunches (28) the brush fibres (20) are bent in a selected direction of the brush (10) at a point in the brush fibres (20) that is farther from the body (12) than the brush surface (26) . 7. Brush according to any of Claims 1 - 6, characteri zed in that at least some of the brush fibres (20) are crimped in order to increase the collection capacity.

8. Brush according to an of Claims 1 - 7, characteri zed in that the bristle bunches (22) are attached to the body (12) at such a distance from each other that the bristle bunches (22) touch each other in the brush surface (26) .

9. Brush according to any of Claims 1 - 8, characteri zed in that the selected direction is the direction of rotation of the brush (10) .

10. Brush according to any of Claims 1 - 9, characteri zed in that the bending point of the brush fibres (20) of the second bristle bunches (26) can be at a distance from the base end (44) of the brush fibres (20) that corresponds to 20 - 80 % of the length of the portion of the brush fibre (20) between the base end (44) and the free end ( 48 ) of the brush fibres ( 20 ) of the second bristle bunches (28).

11. Brush according to any of Claims 1 - 10, characteri zed in that in the second bristle bunches (26) the brush fibres (20) are of polyester.

12. Brush according to any of Claims 1 - 11, characteri zed in that the bristle bunches (22) are attached at right angles to the body (12) of the brush (10). 13. Brush according to any of Claims 1 - 12, characteri zed in that the diameter of the brush fibre (20) is, in the case of the shorter bristle bunches (25), 0.3 mm - 8.00 mm, preferably 0.5 - 1.5 mm and, in the case of the brush fibres (20) of the second bristle bunches (26), 0.7 mm - 10.00 mm, preferably 1.0 - 2.0 mm, the diameter of the brush fibre (20) increasing along with the viscosity of the oil being collected.

14. Brush according to any of Claims 1 - 13, characteri zed in that the length of the bristle bunch can be 30 mm - 500 mm, preferably 50 - 200 mm.

15. Brush according to any of Claims 1 - 14 characteri zed in that the brush fibres (20) of the second bristle bunches (28) are bent at a distance from the base end (44) of each brush fibre (20) , which distance is at the bend 5 - 20 mm greater than the distance of the free ends (44) of the first bristle bunches (25) from the outer surface (24) of the body (12) .

16. Collection device for collecting oil from water in a machine-aided manner, which collection device (100) includes a frame (102) for suspending the collection device (100) from a base (200), at least one brush (10) for collecting oil from water (300), suspended with the aid of a rotation shaft (104) from the said frame (102) , operating devices for rotating the said brush (10) in the frame (102) , a receptacle (108) for storing the collected oil, and a scraper (106) fitted in connection with the brush (10) for scraping oil from the brush (10) into the receptacle (108) , in which the brush (10) includes

- a body (12) arranged to form a circle (14) arranged to be supported around the rotation shaft (104) of the collection device (100), which body (12) includes an outer surface (24) ,

- bristle bunches (22), comprising several individual brush fibres (20) attached to the said outer surface (24) to collect oil, each of which brush fibre has two ends, i.e. a base end (44) and a free end (48), which bristle bunches (22) include first bristle bunches (25) and second bristle bunches (28), of which the second bristle bunches (28) are greater in length between the free end (48) of the brush fibres (20) and the outer surface (24) of the body (12) than the first bristle bunches (25), which said bristle bunches (22) form a continuous brush surface (26) on the brush (10) , characteri zed in that in the said second bristle bunches (28) the brush fibres (20) are bent over a selected length in a selected direction, which direction differs from direction of the brush fibre (20) over rest of the length of the brush fibre (20) .

17. Collection device according to Claim 16, characteri zed in that the said operating devices are arranged to rotate the brush (10) at a circumferential velocity of 60 - 110 cm/s, in order to transfer the oil to the scraper (106) .

18. Collection device according to Claim 16 or 17, characteri zed in that the scraper (106) is a comb-like element arranged to push between the brush fibres (20) as the brush (10) rotates against the scraper (106) .

Description:
BRUSH FOR COLLECTING OIL FROM WATER USING A COLLECTION DEVICE AND A CORRESPONDING COLLECTION DEVICE

The invention relates to a brush for collecting oil from water using a collection device, which brush includes

- a body arranged to form a circle and arranged to be supported around the rotation shaft of a collection device, which body includes an outer surface,

- bunches of bristles, comprising several individual brush fibres attached to the outer surface to collect oil, each of which brush fibre has two ends, i.e. a base end and a free end, which bristle bunches include first bristle bunches and second bristle bunches, of which the second bristle bunches are greater in length between the ends of the brush fibres than the first bristle bunches, which bristle bunches form a continuous brush surface on the brush .

The invention also related to a corresponding collection device for collecting oil from water in a machine-aided manner.

Known from the prior art is a Finnish patent publication FI 125029 B, which discloses a collection device according to the prior art for collecting oil form the surface of water. The collection device includes a rotating brush, which collects oil from the surface of the water into the brush fibres, and a scraper, which collects the oil from the brush fibres into a receptacle. Bristle bunches of even length or different length, which are straight in the direction of the radius of the cross-section of the body of the brush, are used in the brush. A drawback of such a collection device is the limited ability of the brush to bind oil to itself, as particularly low-viscosity oils flow more easily back into the water from the surface of the brush fibres before the brush fibres come into contact with the oil-collecting scraper. Thus the collection efficiency of the collection device remains deficient. Also known from the prior art are publications WO 2007/071813 Al and EP 0069496 Al, which disclose a brush that comprises bristle bunches of two differently sized straight bristles. The differently-sized bristle bunches form recesses in the surface of the brush for removing water. Such brushes are not, however, particularly effective in collecting oil.

The invention is intended to create a more effective brush than brushes of the prior art for collecting oil from water using a collection device. The characteristic features of the present invention are stated in the accompanying Claims 1. The invention is also intended to create a more effective collection device than a collection device of the prior art for collecting oil from water in a machine-aided manner. The characteristic features of the present invention are stated in the accompanying Claim 16.

This intention can be achieved by means of a brush for collecting oil from water using a collection device, which brush includes a body arranged to form a circle and arranged to be supported around the rotation shaft of the collection device, which body includes an outer surface. In addition, the brush includes bristle bunches consisting of several individual brush fibres, attached to the outer surface for collecting oil, each of which brush fibres has two ends, i.e. a base end and a free end. The bristle bunches include first bristle bunches and second bristle bunches, of which the second bristle bunches are longer over the distance between the brush fibres free ends and the outer surface of the body than the first bristle bunches. The bristle bunches form a continuous brush surface on the brush. In the second bristle bunches, the brush fibres are bent over a selected length in a selected direction, which direction differs from the direction of the brush fibres over the rest of the length of the bristle bunch and which selected length is greater than the length of the first bristle bunches from the outer surface of the body.

The greater oil-collection efficiency of the brush according to the invention compared to brushes of the prior art is based on the fact that, when the brush rotates, to the direction of the trough-like structure formed by the bent brush fibres of the second bristle bunches, the through-like structure collects oily water into itself. On the other hand, the second bristle bunches increase the total surface area of the brush's brush fibres and in turn the surface area to which oil can adhere by capillary action with the aid of adhesion between the brush fibres. If the brush is rotated in the opposite direction, then the increase in total surface area caused by the second bristle bunches leads to an increase in the oil-collection efficiency. In this connection, reference to the length of the second bristle bunches in a direction at right-angles to the brush surface means that the brush fibres of the second bristle bunches extend farther from the brush body that the brush fibres of the first bristle bunches forming the brush surface, even though the brush fibres of the second bristle bunches can be at an angle deviating from at a right angle relative to the body.

In other words, the brush fibres in the second bristle bunches are bent in the selected direction of the brush at a point in the brush fibres that is farther from the body than the brush surface.

The bent brush fibres of the second bristle bunches lift oil from the surface of the water into the trough-like structure parallel to the shaft of the brush, formed between them and the continuous brush surface. With the aid of the trough-like structure, the oil is lifted efficiently from the water, as the continuous brush surface formed by the first bristle bunches fills rapidly with oil and limits the oil-collection capacity. This also prevents low-viscosity oils from escaping quickly between the brush fibres, as the bent brush fibres of the second bristle bunches collect oil in the trough parallel to the brush shaft, formed in the bend in the brush fibres. With the aid of the bent brush fibres, oil is effectively transferred at least as far as the scraper, which removes the oil from the brush fibres into the receptacle. In this way the efficiency of the collection increases and larger amounts of oil can be removed in a shorter time. The selected direction is preferably the direction of rotation. The ability of the trough-like structure of the second bristle bunches to collect effectively oily water can then be exploited.

The second bristle bunches can be 1.5 - 3 times, preferably 2.0 - 2.5 times the length of the first bristle bunches. The second bristle bunches will then be sufficiently long for the bend formed in them to lie outside the continuous brush surface, but on the other hand sufficiently short so that the second bristle bunches do not overlap each other on the circle formed by the brush body.

The second bristle bunches can be bent at an angle of 40 - 90° relative to the longitudinal direction of the other bristle bunches, in order to form the trough-like structure for collecting oil against the brush surface. With the aid of the second bristle bunches, a trough-like structure is then formed outside the continuous brush surface and the bent parts of the brush fibres of the second bristle bunches are at such an angle that they also prevent oil from flowing out of the trough-like structure immediately the oil is lifted from the level of the water surface.

The point of bending of the brush fibres of the second bristle bunches can be at a distance from the base end of the brush fibres which corresponds to 20 - 80 % of the length of the brush fibres between the base end and free end of the brush fibres of the bristle bunch .

The individual brush fibres in the second bristle bunches are preferably of polyester. Polyester retains its shape, to which it has been formed in the manufacturing stage, which is especially important in the bent second bristle bunches, so that the trough-like structure will remain, despite the stress of the scraper. In other words, in the second bristle bunches the brush fibres should be sufficiently stiff to be able to be able to resist the mass of the oil adhering to the trough-like structures formed by the second bristle bunches when the trough-like structure lifts oil from the surface of the water. The body is preferably one of the following: a brush drum, a brush belt, or a chain consisting of body elements. As the body formed as a brush drum is symmetrical it is easy to manufacture and can have an inflexible structure. In a brush belt, the number of bristle bunches can be greater that in a brush drum, permitting a greater amount of oil to bind at a time to the brush. A brush belt also permits the scraper to be placed higher above the surface of the water. The body elements are easily replaced and the whole brush need not be rejected if some of the bristle bunches have become unusable.

The ratio of the second bristle bunches to the first bristle bunches is arranged to be such that, in the direction of rotation of the brush, a gap remains between the consecutive second bristle bunches, to lead oil to the trough-like structure. At the same time, the length of the portion of the brush fibres of the second bristle bunches bent in the direction of the circumference of the brush is also arranged to be such that a gap is formed. In other words, the ratio of the second bristle bunches to the first bristle bunches and the length of the portion of the second bristle bunches bent in the direction of the circumference of the brush are arranged to be such that the second bristle bunches do not overlap each other. For example, if the length of the bent portion of a second bristle bunch is 50 % of the total length of a brush fibre of the second bristle bunch, the ratio of the second bristle bunches to the first bristle bunches can be 1:4 - 1:8. If, on the other hand, the length of the bent portion of the second bristle bunch is 20 % of the length of a brush fibre of the second bristle bunch, the ratio of the second bristle bunches to the first bristle bunches can be 1:2 - 1:4.

The bristle bunches are preferably attached perpendicularly to the body of the brush. The bent second bristle bunches will then form trough-like structures with a greater volume for collecting oil.

The diameter of the brush fibre can be, in the case of the first bristle bunches, 0.3 mm - 8.00 mm, preferably 0.5 - 1.5 mm and, in the case of the second bristle bunches, 0.7 mm - 10.00 mm, preferably 1.0 - 2.0 mm, with the diameter of the brush fibre increasing in step with the viscosity of the oil being collected. A sufficiently large surface area will then be obtained for low-viscosity fluid oils, so that the oil adheres effectively between the brush fibres by adhesion. On the other hand, with a suitable brush-fibre diameter, the brush fibres of the second bristle bunches will achieve a sufficient stiffness not to bend due to the forces created by the oil being lifted, in the opposite direction to the direction of travel of the brush when lifting oil .

The length of the bristle bunch can be 30 mm - 500 mm, preferably 50 - 200 mm. In this context, the term length refers to the distance between the base end and the free end of the brush fibre. The number of free ends of the brush fibres of a bristle bunch can be 20 - 200, preferably 38 - 60 items. This number is preferably reached by bending 10 - 30 fibres in two and attaching them at the bend to the body of the brush by punching, according to the prior art. The number of brush fibres is also affected by the size of the bristle hole and the thickness of the brush fibre, which are selected according to the desired result.

The length, in the direction of the tangent of the brush, of the trough-like structure formed by the second bristle bunches can be 15 - 45 mm.

The diameter of the brush can be preferably 0.2 - 2.5 m. The choice of diameter of the brush is affected by the available collection device and its construction.

35 - 65 % of the surface area of the brush body is preferably free in order to remove water, the rest of the surface area being covered by brush fibres. Sufficient space will then remain in the gap of the brush fibres for the water to escape between the brush fibres .

The second bristle bunches are preferably bent at a distance from the base end of each brush fibre, which distance is 5 - 20-mm greater than the distance of the free ends of the first bristle bunches from the outer surface of the body.

The brush fibres are preferably punched in bristle bunches into the body, when the perforation made in the body for the bristle bunches can be patterned to create addition effectiveness.

In this context, reference to a continuous brush surface means a brush surface, in which there are no areas that are completely empty of bristles, though the brush itself can be assembled from separate consecutive parts and have a helically arranged structure .

At least some of the brush fibres are preferably crimped to increase the collection capacity. In the crimped brush fibres, the bottoms of the crimping forms cups, to which the oil can adhere .

The bristle bunches are preferably attached to the body at such a distance from each other that the bristle bunches touch each other in the brush surface. Thus the brush surface is made to be continuous .

According to one embodiment, in the second bristle bunches the brush fibres can be bent into a curve of the radius of a circle, in such a way that the direction of the base end of the brush fibre is at 40 - 90° relative to the direction of the free end of the brush fibre. In the present application, the term bending means that the brush fibres may have been either physically bent from straight brush fibres into bent brush fibres, or alternatively the brush fibres may have been formed already in the same shape that would have been achieved through bending.

In this connection it should be understood that, when speaking of the dimensioning of the brush and the brush fibres, the structure according to the invention can be scaled from small brushes with a diameter of ten centimetres up to brushes with a diameter of two metres. The dimensioning of the brushes is then naturally also scaled correspondingly in the case of the brush fibres' length, thickness, and number, whereas, for example, the depth of the trough-like structure and the length of the parts of the bent brush fibres of the second bristle bunches remain essentially the same. Similarly, the dimensions of the brush also change according to the viscosity of the oil being collected, heavier oil fractions requiring greater fibre thicknesses to achieve sufficient stiffness.

The intention of the collection device according to the invention can be achieved by means of a collection device for collecting oil from water mechanically, which collection device includes a frame for suspending the collection device from a base, at least one brush for collecting oil from water suspended with the aid of its rotation shaft from the said frame, operating devices for rotating the said brush in the frame, a receptacle for holding the collected oil, and a scraper arranged in connection with the brush for scraping the oil from the brush into the receptacle. The brush includes a body arranged to form a rotation for attaching the body around the rotation shaft of the brush device and bristle bunches consisting of the several individual brush fibres attached to the outer surface belonging to the body for collecting oil, each of which brush fibre has two ends, i.e. a base end and a free end. The bristle bunches include first bristle bunches and second bristle bunches, of which the second bristle bunches are longer in length between their ends than the first bristle bunches, which bristle bunches form a brush with a continuous unified brush surface. In the second bristle bunches, the brush fibres are bent over a selected length in a selected direction, which direction differs from the direction of the brush fibre over the length of the rest of the brush fibre. By means of such a collection device a considerably greater capacity is achieved, using a simpler implementation then previously, than that of collection devices according to the prior art.

The selected direction, in which the second bristle bunches are bent, is preferably the direction of rotation of the brush. The bent brush fibres of the second bristle bunches then form a trough-like structure, in which oil travels effectively to the scraper .

The angle of the scraper relative to the radial direction of the brush can be 20 - 45°, preferably in such a way that the point of the scraper points in the direction of the tangent of the brush. The oil that has collected on top of the scraper will then flow by gravity from the scraper into the receptacle. The point of the scraper preferably travels close to the brush body, at a distance of about 10 - 20 mm from the body, and the base of the spikes belonging to the scraper is at a distance from the body of about 40 - 60 % of the length of the first bristle bunches .

In the device according to the invention, the brush can be arranged to be rotated at a circumferential velocity of 20 - 200 mm/s, preferably 50 - 100 mm/s in the case of heavy oils. If the diameter of the body of the brush is about 500 mm, the rotational speed will then be 0.5 - 4 rpm. Heavy oil flows slowly from between the brush fibres of the second bristle bunches, so that the rotational speed can be quite low, thus assisting the cleaning of the brush fibres of the second bristle bunches by the scraper. In the case of light oils, the brush according to the invention can be arranged to be rotated at a rotational speed of as much as 10 - 20 rpm. With light oils, the rotational speed should be greater, so that the oil has not time to flow off the trough-like structure formed by the second bristle bunches.

The operating devices are preferably arranged to rotate the brush at a circumferential velocity of 60 - 110 cm/s, to transfer the oil to the scraper. The circumferential velocity is of great importance, as at too great a circumferential velocity oil is splashed around the brush and, on the other hand, at too low a circumferential velocity it flows through the brush.

The scraper is preferably a comb-like element arranged to push between the brush fibres as the brush rotates against the scraper. The scraper is then easy to implement and does not damage the brush fibres unlike, for example, pressing between rollers.

The base is preferably a water-traffic vessel or a skimmer. These are highly suitable as bases for the collection device according to the invention.

The operating devices for rotating the brush can be any of the following: an internal-combustion engine, an electric motor, a hydraulic motor, or a pneumatic motor.

In the present application, the length of the first and second bristle bunches and the brush fibres refers to their length between the outer surface of the body and the free end of the brush fibre, though the brush fibre itself could be attached bent in two to the body of the brush.

In the following, the invention is described in detail with reference to the accompanying drawing showing some embodiment of the invention, in which

Figure 1 shows a cross-section of a first embodiment of the brush according to the invention,

Figure 2 shows a cross-section of a second embodiment of the brush according to the invention,

Figure 3 shows a cross-section of a third embodiment of the brush according to the invention, Figure 4 shows an axonometric view of a floating base, on which the collection device according to the invention is suspended,

Figure 5 shows a cross-section of a first embodiment of the brush according to the invention, when oil is collected using the brush,

Figure 6 shows the brush of the first embodiment according to

Figure 1, in which the second bristle bunches are denser ,

Figure 7 shows the brush of the first embodiment according to

Claim 1, in which the bristle bunches between the second bristle bunches increase in size in the direction of rotation of the brush,

Figure 8 shows an axonometric view of the brush embodiment according to Figure 1 fitted to a roller,

Figure 9 shows one variation of the brush embodiment of Figure

7, in which the first bristle bunches grow in steps,

Figure 10 shows a variation of the brush embodiment according to Figure 8,

Figure 11 shows an axonometric view of a fourth variation of the embodiment of the brush according to the invention, fitted to a roller,

Figure 12 shows an axonometric view of a variation of the embodiment of the brush according to the invention, fitted to a roller.

Figure 1 shows a first embodiment of the brush according to the invention, in which a brush drum forms the body 12 of the brush 10. Generally in all embodiments of the invention the brush 10 includes a body 12 forming an outline with a circular cross-section or circulated around two rollers, from which the brush 10 is supported around the rotation shaft 104 of the brush device, and several individual brush fibres 20 forming bristle bunches 22 attached to the outer surface 24 belonging to the body 12. Each brush fibre has a base end 44 attached to the outer surface 24 of the body 12 and a free end 48. The bristle bunches 22 form the brush surface 26 for the brush 10, which is continuous over the entire outer circumference of the brush 10. The brush fibres of the adjacent bristle bunches in the brush surface support each other in the direction of the tangent of the brush. According to the invention, the bristle bunches 22 include first bristle bunches 25 and second bristle bunches 28. In the second bristle bunches 28 the brush fibres 20 are longer than the brush fibres of the first bristle bunches 25 and the brush fibres 20 of the second bristle 28 are bent in the direction of rotation of the brush 10, thus forming a trough-like structure 30 against the brush surface 26. The trough-like structure 30 can have two open ends 21, which can be seen, for example in Figure 12. The term open end refers to the fact that at this point there are no brush fibres of a second bristle bunch to form an obstacle to the flow of water in the axial direction of the brush. According to Figure 1, there are enough second bristle bunches 28, that the brush fibres 20 of the second bristle bunches 28 bent in the direction of the tangent of the rotation shaft cover at least 50 - 90 % of the area of the outer circumference of the brush 10.

In the embodiment of Figure 1, the brush fibres 20 of the second bristle bunches 28 are bent at an angle of slightly less than 90° relative to the direction of the radius of the rotation shaft. A clearly trough-shaped structure 30, which is sufficiently deep to also retain oils with a high viscosity in the brush 10, is then formed between the bent brush fibres 20 of the second bristle bunches 28 and the brush surface 26. The term depth of the trough-like structure 30 refers to the distance of the end of the brush fibres 20 of the second bristle bunches 28 and the bends 34 from each other. The trough-like structure 30 preferably narrows towards the bend, so that the trough-like structure 30 has its "mouth open" when it meets the surface of the water, so that the oil collects on the inner surface of the trough-like structure. The oil cannot escape from the inner surface from the trough-like structure, when the second bristle bunches rises from the water. The brush has preferably been submerged in the water at least to the extent that each brush fibre remains under the surface of the water at some stage in its rotation. On the other hand, the brush is preferably submerged in the water at most up to its rotation shaft, so that the water has time to leave before the scraper.

The brush fibres are bent in two in the holes in the brush body and attached using a metal staple. The positioning and frequency of the holes are affected by the dimensioning of the scraper and the viscosity of the oil to be collected. The brush fibres can also be permanently attached to the body as part of moulding, i.e. the brush fibres are attached to the body already when moulding it. According to one embodiment, rows of the brush fibres can be formed in cassettes, which are fed into corresponding counter-holes in the brush body. Though only a cross-section of the brush is shown in Figures 1 - 7, it should be understood that the brush has preferably a cylindrical or roller-like structure, as in Figures 8 - 12, which has two edges, i.e. ends. The bristle bunches are preferably fitted to the brush in essentially longitudinal rows, in each of which rows there are bristle bunches of a specific length. According to one embodiment, the rows can be set partly helically in the body, so that the bristle bunches meet the scraper at different times, which prevents vibrations from arising. Though in this connection rows of bristle bunches are referred to, the consecutive bristles are preferably slightly overlapping, to increase the brush's efficiency.

Figure 2 shows a second embodiment of the brush according to the invention, in which the brush's 10 body is a brush belt. In this embodiment, the body 12 forms an elongated circle 14, a kind of oval, at the ends of which are rotation shafts 104. In such an embodiment, the second bristle bunches 28 can be exactly the same as in the first embodiment of Figure 1. Using the brush according to the second embodiment, the advantage is gained over the brush of the first embodiment that with it oil can be lifted farther from the water surface without increasing the size of the diameter of the rotation shaft. The brush can be placed vertically, so that one rotation shaft is below and the other above it, so that the scraper belonging to the collection device can be placed close to the upper rotation shaft. The brush fibres can be attached to the body correspondingly as in the embodiment of Figure 1, but, unlike the first embodiment, the body should be flexible, so that it will withstand the change in shape from curved to straight over the journey between the curve of the rotation shaft.

In the third embodiment of the brush according to the invention of Figure 3, the brush is also elongated, but the body 12 is formed of body elements 32 placed in a chain. At least one row of bristle bunches, or preferably two rows of bristle bunches 22 according to Figure 3 can be attached to each body element. The body elements 32 can, in turn, be attached, for example, to a belt, which is rotated around the rotation shafts 104.

The individual brush fibres used in the brush can be of various fibrous materials such as, for example, polypropylene, polyester, or polyamide. The brush fibres of the second bristle bunches are, for their part, preferably of polyester, which retains its shape, which is important in connection with the bent brush fibres of the second bristle bunch. The bend made in the brush fibres of the second bristle bunches is preferably formed by heat treatment after inserting the bristles.

The cross-section of an individual brush fibre can be round, oval, star-shaped, or some other shape suitable for the purpose, which increases the specific surface area of the brush fibre. The choice is affected, as is the choice of the brush fibre's diameter, by the viscosity of the oil to be collected. In the bristle bunch, the fibre can be straight or crimped, and in the second bristle bunch straight and bent or straight and crimped. In the case of the thinnest oil to be collected, i.e. diesel, the thinnest possible fibres are preferably used, preferably nylon fibres, which are crimped or have an oval-shaped or star-shaped cross-section. With the aid of crimping the brush fibres, the efficiency of the brush can be increased considerably, as the crimping forms pockets between the fibres, in which the collected oil remains .

The material used in the body of the brush can be, for example, plastic, metal or a composite, depending on the embodiment and its requirements. The density of placing of the brush fibres of the bristle bunches of the brush must not be too great, to allow water to leave the brush before the scraper. The placing density of the brush fibres can be 0.5 - 2.5 mm, i.e. each brush fibre is at a distance of 0.5 - 2.5 mm from the adjacent brush fibre. It should be understood that the inner surface of the body includes attachment elements for locking the body around the rotation shaft, even though these are not shown in the figures. The attachment elements can be according to the prior art.

Figure 4 shows one embodiment of the collection device 100 according to the invention attached to a base. The collection device according to the invention is preferably attached to the side or in front of a floating vessel or skimmer acting as the base, when the flow of water caused by the floating vessel does not move the oily water out of the way of the collection device. The collection device includes a frame 102 arranged to be suspended from the vessel 200, at least one brush 10 for collecting oil from the water 300 and suspended from the frame 102 with the aid of a rotation shaft 104, operating devices for rotating the brush 10, a receptacle 108 for holding the collected oil, and a scraper 106 fitted in connection with the brush 10 for scraping oil from the brush 10 into the receptacle 108. The brush used in the collection device 100 is a brush according to the invention. In the embodiment of Figure 4, the brush 10 is a brush 10 according to the second embodiment shown in Figure 2. The area for collection is preferably delimited using the guides 114 shown in the figure, so that the oily water is guided to the collection device.

The scraper 106 is shown in greater detail in Figure 5, which also shows the oil 400 to be collected in the trough-like structures 30. The scraper 106 preferably includes a blade part 110, which lies nearly against the body 12 of the brush 10. The blade part 110 of the scraper 106 can be a comb-like element, through which the brush fibres 20 of the bristle bunches 22 travel as the oil detaches from the surfaces of the brush fibres to the blade part 110. The oil collected from the scraper 106 can flow into a receptacle 108. Figure 5 shows the preferred direction of rotation of the brush 10. Preferably when the scraper is a comb-like structure the angle between the spikes of the comb-like structure is rounded, to be able to prevent the brush fibres from sticking between the spikes. Figure 6 shows a brush 10 corresponding to the embodiment of the brush according to Figure 1, in which the second bristle bunches 28 are set more densely than in the brush 10 shown in Figure 1. The ratio of the number of second bristle bunches to that of the first bristle bunches can vary according to the length of the bent part of the second bristle bunches. In this case, however, a limitation lies in the fact that the second bristle bunches set on the circumference must not overlap each other, but a gap should remain between them, from which the oil can enter the trough-like structure formed by the second bristle bunches. According to Figures 7 and 9, the bristle bunches 22 between the second bristle bunches 28 can lengthen or shorten, in the direction of rotation, in the gap between two second bristle bunches 28. The lengthening can, according to Figures 7 and 9 be linear, or, according to Figure 10, stepped in the case of the adjacent first bristle bunches. The first bristle bunches can then include bristle bunches of several different lengths. The capacity of the trough-like structure formed by the second bristle bunches with the aid of the first bristle bunches of different lengths ban be increased, thus increasing the efficiency of the brush .

In the roller-like brush 10 shown in Figure 11, the bristle bunches form bristle discs 40 and 42 transversely in the brush, of which some are traditional intermediate discs 40 equipped with bristle bunches of even length and some are bristle discs 42 containing second bristle bunches according to the invention. Such a more enclosed trough-like structure is particularly well suited to collecting oils with a specific viscosity. Recesses, which effectively collect oil, are formed in the trough-like structure. For its part, Figure 12 shows a roller-like brush 10, in which the consecutive second bristle bunches 28 in the longitudinal direction of the brush form rows 46, which are preferably at a slant relative to the longitudinal direction of the brush. The slant is preferably arranged in such a way that the slant is symmetrical relative to the centre point of the brush, so that V-shaped rows of second bristle bunches are formed in the brush, which collect oil in the centre of the brush or, alternatively, at the ends of the brush, depending on the direction of rotation of the brush. In this context, the term trough-like refers to the shape of a cylinder split in the direction of the axis of rotation, in which both ends are open to allow water to escape. The following is a description in the light of details of an embodiment of the brush according to the invention. In this embodiment, the diameter of the brush's body is 800 mm (the body without brush strips and at the level of the brush surface has a diameter of 910 mm) . The material used in the brush fibres of the first bristle bunches of the brush can be polypropylene, the diameter of a brush fibre 0.4 mm and its length 40 mm. The material used in the longer brush fibres of the second bristle bunches can be polyethylene, when the diameter of a brush fibre is 0.5 mm and its length 80 mm. The second bristle bunches are preferably bent at a distance of 50 mm from the base end of each brush fibre. The brush can then be used for the collection of heavy oils. The brush is completely covered with bristles and the bristle bunches can be over a width of 480 mm on a body of 550 mm, so that measured at the brush surface the brush's diameter is 910 mm. The straight brush fibres can be crimped, but the crimping is very little relative to the fibre's thickness. The brush's surface area can be about 1.3 - 1.5 m . In tests, a rotating speed of 1 rpm was used, when the circumferential velocity was 48 mm/s, and using a brush with the aforementioned dimensioning an oil-collection capacity of 468 kg/h was achieved, which in terms of a square metre is 342 kg/m 2 /h of heavy fuel oil (POR 180, at a temperature of 20°C) . The comb-like scraper used is preferably set at an angle relative to the brush fibres striking it. In the scraper, there are as many gaps as there are bristle-bunch rows in the brush, i.e. in this case 32. In the scraper there are then 31 "comb" spikes, the width of the spikes being 80 mm. Compared to a brush according to the prior art equipped only with straight fibres, in which the length of the fibres is 70 mm and the diameter and the width of the brush body is the same as in the previous example, the use of the brush according to the invention achieves an oil-collection capacity of as much as 30 % more. The brush and collection device according to the invention can be used for collecting oils and oil-like chemicals from water in both fresh and sea-waters. The brush and collection device according to the invention can also be adapted for use in collecting other liquid impurities from water besides oil, as the operating principle of the second bristle bunches is also suitable for collecting other liquid impurities.