The invention relates to a system for recycling used tires comprising a high-pressure fluid spray head.
Such an installation makes it possible to separate the materials constituting a tire for the purpose of recycling or reusing at least some of the materials.
Such a system is described notably in document D1 (U.S. Pat. No. 5,341,996). It notably comprises a means for holding and rotating a tire, and a means for spraying jets of fluid onto the tire to be treated. The spraying means comprises several spray heads each comprising an axis of symmetry. The spraying means also comprises a means for orienting the axis of symmetry of the heads perpendicularly to the surface of the tire to be treated and for rotating the heads about their axis of symmetry. On the periphery of the heads, on one and the same radius, a plurality of outlet nozzles are positioned which direct jets of fluid under pressure in a direction perpendicular to the tire to be treated or at an angle in order to treat surfaces of the tire to be treated that do not pass directly beneath the spray heads.
Such a system makes it possible to separate the metal portions from the fabrics and rubbers of the user tires, but it is not very efficient. The particles of material torn away from the carcass of the tires are quite coarse and consequently quite difficult to recycle. Equally, many passes are often necessary to eliminate all the particles of fabrics and rubber.
One object of the invention is to propose a shredding system that is more efficient than the known systems.
For this reason, the invention proposes a system for recycling used tires comprising at least one head for spraying a fluid at high pressure onto a surface to be treated. The spray head comprises a body mounted so as to rotate about an axis of rotation that is substantially perpendicular to the surface to be treated, and a plurality of outlet nozzles each appropriate for directing a jet of fluid toward the surface to be treated.
According to the invention, the system is characterized in that the plurality of outlet nozzles comprises at least two outlet nozzles that are appropriate for orienting respective jets of fluid in at least two directions having different angles relative to the axis of rotation. In other words, according to the invention, the angles between the directions of the jets and the axis of rotation of the spray head are different so that the jets attack the surface to be treated at different angles of attack and that the trajectories of the jets intersect several times when the head is rotated and/or when the surface to be treated moves in front of the spray head. The result of this is a more rapid cutting of the fabrics surrounding the metal carcass of the treated tire. Equally, smaller residual particles are obtained after cutting which are therefore more easily usable or recyclable. Finally, after complete treatment of the tire, the metal carcass is cleaner.
Angles between the directions of the jets and the axis of rotation of the spray head of between −35° and +35° already give good results. Tests show that the range −25° to −5° or 5° to 25° makes it possible to obtain optimum results.
When the spray head is rotated, each jet attacks the surface to be treated in a ring centered on the axis of rotation of the spray head irrespective of the angle of attack of the jet. In order to have the largest possible surface area attacked for a more rapid treatment, the angles between the directions of the jets of fluid and the axis of rotation of the spray head may be chosen such that the zones of impact of the jets of fluid on the surface to be treated when the spray head is rotated form substantially adjacent or slightly overlapping rings.
According to a variant, the outlet nozzles of the plurality of outlet nozzles are situated on at least two radii that are substantially different from the axis of rotation of the spray head. Therefore, increasing the number of angles of attack and increasing the number of radii produces a larger number of different trajectories which further improves the effectiveness of the spray head.
The fluid used may be water under high pressure which has the advantage of being cheap and easily recyclable after cutting of the tires, compared with other fluids such as oil. Equally, water laden with abrasive particles makes it possible to use lower pressures.
A further subject of the invention is a method for recycling used tires according to which a tire is shredded by spraying a high-pressure fluid through a plurality of jets of fluid in the direction of a surface of the tire to be treated, the jets being able to rotate about an axis of rotation substantially perpendicular to a surface to be treated. The method is characterized in that the jets of fluid are oriented in at least two directions having different angles relative to the axis of rotation.
The invention will be better understood and other features and advantages will appear on reading the following description of an exemplary embodiment of a spray head according to the invention. The description should be read with reference to the appended drawings in which:
A system 1 for recycling tires according to the invention, as shown in
In the example of
It should be noted that the shape of the body of the spray head is immaterial. The shape of the outlet nozzles is also immaterial, the important aspect being only the direction of the jets coming out of said outlet nozzles.
In the example of
The impact of each jet on the surface to be treated has a substantially circular shape if the direction of the jet is substantially perpendicular to the surface to be treated, or substantially elliptical if the direction of the jet is not perpendicular to the surface to be treated.
When the spray head is rotated on the axis of symmetry 22, the impact of each jet of fluid on the surface to be treated has substantially the shape of a ring. When the surface to be treated travels in front of the spray head (when the tire 3 to be recycled is rotated), the impact ring moves along the surface to be treated.
In the example of
Number | Date | Country | Kind |
---|---|---|---|
0852989 | May 2008 | FR | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/EP09/55391 | 5/5/2009 | WO | 00 | 1/20/2011 |