METHOD FOR PRODUCTION OF PRODUCTS FROM POROUS POLYMER MATERIALS

Abstract: The present invention is for a method for production of products from porous polymer materials and a device for practicing the method. The purpose of the present invention is to treat recycled or fresh material so that it is sterilized and bad smell is removed and that in connection therewith it is prepared in such a way that it may directly be used for production of new products. After disintegration the pieces of disintegrated material are supplied through a supply channel (12) to a treament chamber (1), wherein they are both radiated by UV light and coated with glue. The pieces so treated are removed from the treatment chamber by a conveyor (13) and are directly transferred to a second conveyor (27). Carried by the conveyor (27) the material is moved through several microwave heating chambers (33, 34, 35, 36).

Description: Method for production of products from porous polymer: materials. The present invention is for a method for production of products from porous polymer materials and a device for practicing the method. The method and device of the invention are primarily intended to be used by recycling of polymer material but may also be used for freshly produced material. Porous polymer material primarily means that kind of material which is used for furniture, mattresses and cushions, whereby the polymer is different kinds of polyether. Besides handling of the very voluminous goods and other technical problems the recycling of used such materials also brings with it special problems which are related to that the material may be both infected and as a consequence hereof or for other reasons be bad smelling. Bad smell may also be caused by the starting components (for example amines) which have not reacted completely by the manufacture of the polymer. This is especially essential when the original products which shall be recycled are mattresses from hospital beds and the like. The purpose of the present invention is to treat recycled or fresh material so that it is sterilized and bad smell is removed and that in connection therewith it is prepared in such a way that it may directly be used for production of new products. For production of products by the method of the invention porous polymer materials of low volume weights, 10-50 kg/m , are used. Primarily the starting material is recycled mattresses, cushions, stuffing materials and other furniture materials. This starting material is disintegrated into small pieces in the order of 1-30 mm. Using a flow of air and gas these small parts are blown into the treatment chamber where they are both radiated for sterilization and removal of smell causing substances and also are given a coating of glue in order that they will be put together to new products in the further processing. In a second treatment step the material so obtained is heated using microwave energy for final sterilization and in some applications also for shaping final products. The radiation is preferably by UV-light and during a coincident glue coating, whereby the glue is supplied in the form of very small drops which do not cover the whole surface of the particles but only gives a pointwise coating. UV- radiation and glue coating preferably takes place in the same operation in the treatment chamber. The use of microwave energy for the subsequent heating has among others the advantage that the supply of energy takes places immediately in the whole of the material, whereby a complete sterilization is secured. Suitable conditions for treatment can be a heating time of about 3 minutes and a maximum temperature in the material of o about 80 C. The invention will below be described more in detail with reference to the enclosed figures. Figure 1 shows a side view of a device for using the invention and figure 2 shows the same device from above. Figure 3 shows a cross section of a treatment chamber for use by the method of the invention and figure 4 shows a cross section of the same chamber, at right angle to that of figure 3. After disintegration the pieces of disintegrated material are supplied through a supply channel 12 to a treatment chamber 1, wherein they are both radiated by UV light and coated with glue. The pieces so treated are removed from the treatment chamber by a conveyor 13 and are directly transferred to a second conveyor 27. Carried by the conveyor 27 the material is moved through several microwave heating chambers 33, 34, 35, 36 having intermediate connecting chambers 37, 38, 39. Each heating chamber comprises microwave transmitters 41-48. Thereupon the material passes through a final chamber 40, in which it is cooled and the process air is removed through the air channels 49-52. During conveyance on the conveyor 27 the material is delimited upwards by a cooperating band 30, having essentially the same dimensions as the conveyor 27. In the microwave heating chambers the material is heated and the single pieces are bound together by the glue particles, whereby the glue dries, hardens or otherwise reacts chemically. The final product so obtained is a continous strip of porous polymer material, having the desired volume weight, which strip can be separated and cut to desired shape. The treatment chamber is shown more detailed in figures 3 and 4. The material is supplied to the chamber through an inlet 12 and is preferably conveyed by means of an air flow. In the top of the chamber there are several lamps 2-7, which emit UV- radiation. This also initiates the formation of ozon which takes part in the process inside the chamber. Liquid glue is supplied through a tube 11 and spraying dies 8, 9, 10. The material supplied falls down through the chamber 1 while it is being radiated and sprayed upon with glue drops. The spraying of glue is adapted as needed to cooperate with the UV- radiation, e.g. by positioning the dies 8, 9, 10 somewhat lower in the chamber than as shown in the figures. In the bottom of the chamber there is a conveyor 13, the surface of which is perforated so that air may pass through it. Air is collected in a collecting channel 16 below the conveyor and is removed from the plant. The conveyor 13 is operated at constant speed over the rolls 14 and 15 and the treated material is removed through the opening 18 which is delimited by an upper edge 17. Along the larger opposing walls 19 and 20 of the chamber a movable plastic foil 21, 22 can be arranged which during the process may move downwards continuously or stepwise. The plastic foil is supplied from the rolls 23 and 24 and is collected on the rolls 25 and 26. The plastic foil is made from a material, to which the porous polymer and the glue adheres poorly and in this way it is avoided that material sticks to the walls of the chamber. The treated material is collected as mentioned in the bottom of the chamber and the process parameters are so controlled that suitable amount of material is present at the lower end of the chamber and there functions as a filter for the outflowing air. The upper edge 17 of the outflow opening 18 is preferably adjustable in different directions, whereby the compression and other properties of the material which is conveyed out from the chamber to some extent can be controlled. The delimiting edge 17 as shown in the figures is straight but it may also be given for example a wavelike shape. Preferably the so obtained material is directly transferred to the following conveyor 27 shown in figures 1 and 2 for further treatment in the microwave heating chambers 33-36. It is also possible to transfer the material from the treatment chamber to closed molds before the treatment in microwave heating chambers in order to obtain a shaped product.

Claims: CLAIMS 1) Method for manufacturing of products from porous polymer materials, characterized therein, that recycled porous polymer material is disintegrated into small pieces, that these pieces thereupon during free fall in an flow of air or gas are exposed to UV-radiation and coated with particles of glue and that the so obtained material is heated by microwave energy to such a temperature and with such a duration that the material is sterilized. 2) Method according to claim 1, characterized therein, that UV-radiation and glue coating take place simultaneously. 3) Method according to any of the preceding claims, characterized therein, that the material simultaneously with heating with microwave energy is shaped and bound to a final product. 4) Device for simultaneous radiation and spray coating of disintegrated polymer material in a chamber, charaterized therein, that a film of a polymer material of another kind is movably arranged along at least two of the walls of the chamber.

Inventors: GUSTAFSSON PER ERIK, HAEGGSTAM ULF, JANSEN PETER, GUSTAFSSON, PER, ERIK, HAEGGSTAM, ULF, JANSEN, PETER
Applicants: CIRRUS AB, GUSTAFSSON PER ERIK, HAEGGSTAM ULF, JANSEN PETER, GUSTAFSSON, PER, ERIK, HAEGGSTAM, ULF, JANSEN, PETER
Application year: 1996
Main classification: C08J9
IPC codes: A61L2, B29B13, B29B17, B29C44, C08J9