INFILL FOR SYNTHETIC AND HYBRID TURFS AND TURFS SO OBTAINED

Abstract

A synthetic turf having a mat with a face arranged adjacent to a surface to coat, and a face opposite the face. The turf includes a plurality of blades made of a synthetic material that are connected to the mat. Above the face of the mat, an infill material is provided that is arranged among the blades. The infill material includes a predetermined percentage by volume of a vegetable material consisting of rachis of cereal ear.

Claims

1. An infill material for synthetic turfs, or hybrid synthetic-natural turfs, for sports, or recreational, or ornamental uses comprises a predetermined percentage by volume of a vegetable material consisting of rachis of cereal ear; wherein the rachis of cereal ear is not coated by a layer, or film, of material.

2. The infill material, according to claim 1, wherein said percentage by volume of said material consisting of rachis of cereal ear in said infill material is set between 5% and 90%.

3. The infill material, according to claim 1, wherein said vegetable material consisting of rachis of cereal is maize cob.

4. The infill material, according to claim 1, wherein said material infill consists entirely of the vegetable material consisting of rachis of cereal ear not coated by a layer, or film, of material.

5. The infill material, according to claim 1, wherein the vegetable material consisting of rachis of cereal ear not coated by a layer, or film, of material is dried or substantially dried with a moisture content less than 50%.

6. The infill material, according to claim 1, wherein the vegetable material consisting of rachis of cereal ear not coated by a layer, or film, of material has a moisture content less than 30%.

7. The infill material, according to claim 1, wherein said vegetable material consisting of rachis of cereals has a granulometry set between 0.3 mm and 5.0 mm.

8. The infill material, according to claim 5, wherein the dried or substantially dried vegetable material of rachis of cereal ear not coated by a layer or film of coating material is obtained by subjecting to a drying step into a silo a vegetable material of rachis of cereal ear not coated by a layer or film of coating material with an initial moisture content greater than 50%.

9. The infill material, according to claim 8, wherein the vegetable material of rachis of cereal ear not coated by a layer or film of coating material having an initial moisture content than is greater 50% introduced into the silo where an air-flow at a predetermined temperature is also fed for reducing the moisture content from the value greater than 50% to the value less than 50%.

10. The infill material, according to claim 1, wherein the vegetable material consisting of rachis of cereal ear not coated by a layer or film of material is rounded by subjecting the vegetable material consisting of rachis of cereal ear to a rounding treatment.

11. The infill material, according to claim 1, wherein the vegetable material consisting of rachis of cereal ear not coated by a layer or film of material not coated by a layer or film of material is rounded by subjecting the vegetable material consisting of rachis of cereal ear to a rounding treatment and wherein the rounded vegetable material consisting of rachis of cereal ear not coated by a layer or film of material so obtained is dried or substantially dried up to reaching a predetermined moisture content by a drying treatment.

12. The infill material, according to claim 5, wherein the dried or substantially dried vegetable material of rachis of cereal ear not coated by a layer or film of coating material with a moisture content less than 50% is introduced into a bag made of an impermeable material thus avoiding that it can absorb moisture from the external environment until the moment of its use.

13. The infill material, according to claim 1, wherein the vegetable material of rachis of cereal ear not coated by a layer or film of coating material has a bulk density comprised between 0.3 kg/dm.sup.3 and 0.5 kg/dm.sup.3.

14. A synthetic or hybrid synthetic-natural turf for sports or recreational or ornamental uses comprising: a mat having a first face arranged on a surface and a second face opposite to the first face; a plurality of blades of synthetic material connected to said mat and protruding from the second face in such a way to form a synthetic mat; an infill material distributed on the second face of the mat among the plurality of blades of synthetic material, wherein the infill material comprises a vegetable material consisting of rachis of cereal ear which is not coated by a layer or film of material.

15. The synthetic or hybrid synthetic-natural turf for sports or recreational or ornamental uses according to claim 14 wherein the infill material, furthermore, comprises at least a second layer arranged above the layer consisting of rachis of cereal ear which is not coated by a layer or film of material, wherein the second layer consists of: a layer comprising a predetermined percentage by volume of cereal husks; a layer comprising a predetermined percentage by volume of a loose final product from raw material based on ground cork; a layer comprising a predetermined percentage by volume of rachis of cereal ear which is not coated by a layer or film of material; a layer comprising a predetermined percentage by volume of a ligninic and/or resinous material of vegetable origin; a layer comprising a mixture of at least two material selected among: the cereal husks, the loose final product from raw material based on ground cork, the rachis of cereal ear which is not coated by a layer or film of material, the ligninic and/or resinous material of vegetable origin, sand.

16. The synthetic or hybrid synthetic-natural turf for sports or recreational or ornamental uses according to claim 14, wherein the vegetable material of rachis of cereal ear which is not coated by a layer or film of material having a predetermined moisture content less than 50% is stored within a bag which is made of an impermeable material, and wherein, when the vegetable material of rachis of cereal ear which is not coated by a layer or film of material is discharged from the bag to be distributed on the second face of the mat has still the same, or substantially the same, predetermined moisture content less than 50%.

17. The synthetic or hybrid synthetic-natural turf for sports or recreational or ornamental uses according to claim 14 wherein the rachis of cereal ear which is not coated by a layer or film of material is preliminarily dried up to obtaining a predetermined moisture content less than 50%.

18. The synthetic or hybrid synthetic-natural turf for sports or recreational or ornamental uses according to claim 14 wherein the rachis of cereal ear which is not coated by a layer or film of material is rounded by preliminarily subjecting the vegetable material consisting of rachis of cereal ear to a rounding treatment.

19. A synthetic or hybrid synthetic-natural turf for sports or recreational or ornamental uses comprising: a mat having a first face arranged on a surface and a second face opposite to the first face; a plurality of blades of synthetic material connected to said mat and protruding from the second face in such a way to form a synthetic mat; an infill material distributed on the second face of the mat among the plurality of blades of synthetic material, wherein the infill material comprises a layer consisting of a mixture of a predetermined percentage volume of rachis of cereal ear which is not coated by a layer or film of material with a predetermined percentage volume of at least a material selected among: a cereal husks, a loose final product from raw material based on ground cork, a ligninic and/or resinous material of vegetable origin, sand.

20. The synthetic or hybrid synthetic-natural turf for sports or recreational or ornamental uses according to claim 19 wherein the ligninic and/or resinous material of vegetable origin is the tip cap of the cereal which is the portion attaching the kernel to the rachis of the cereal ear.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0099] The invention will be now shown with the following description of an exemplary embodiment thereof, exemplifying but not limitative, with reference to the attached drawings in which:

[0100] FIG. 1 diagrammatically shows a cross sectional view of a possible exemplary embodiment of a synthetic turf in which an infill material, according to the invention, is used;

[0101] FIGS. 2 and 3 diagrammatically show a cross sectional view of two possible exemplary embodiments of the synthetic turf shown in FIG. 1;

[0102] FIG. 4 diagrammatically shows a cross sectional view of a possible exemplary embodiment of a hybrid synthetic-natural turf in which an infill material, according to the invention, is used;

[0103] FIG. 5 diagrammatically shows a cross sectional view of an exemplary embodiment of the turf shown in FIG. 4;

[0104] FIG. 6A diagrammatically shows a cross section view of a fresh corn cob provided with the kernels;

[0105] FIG. 6B diagrammatically shows in plan a kernel of the fresh corn cob of FIG. 6A still provided with the tip cap;

[0106] FIG. 7 diagrammatically shows a side elevation view of a possible silo that can be used for the ensilage of the vegetable material of rachis of cereal ear and to obtain dried or substantially dried vegetable material of rachis of cereal ear not coated by a layer or film of coating material;

[0107] FIG. 8 diagrammatically shows a side elevation view of a possible alternative embodiment of the silo that can be used for the ensilage the vegetable material of rachis of cereal ear and to obtain a dried or substantially dried vegetable material of rachis of cereal ear not coated by a layer or film of coating material;

[0108] FIG. 9 diagrammatically shows a side elevation perspective view of a possible container inside of which the dried or substantially dried vegetable material of cereal ear, according to the invention, can be introduced for being transferred;

[0109] FIG. 10 diagrammatically shows a side elevation view of a possible device for carrying out the rounding treatment of the dried or substantially dried vegetable material of cereal ear, according to the invention;

[0110] FIG. 11 shows an enlargement of the dried or substantially dried vegetable material of cereal ear, which is fed to a device for carrying out the rounding treatment of FIG. 10;

[0111] FIG. 12 shows an enlargement of the dried or substantially dried and rounded vegetable material of cereal ear exiting the device for carrying out the rounding treatment of FIG. 10.

DETAILED DESCRIPTION OF SOME EXEMPLARY EMBODIMENTS

[0112] With reference to FIGS. 1 and 2, a synthetic turf 1, according to the invention, comprises a mat 2 provided with a face 2a, that, in use, is arranged adjacent to a surface 50 to be coated, and with a face 2b opposite to the face 2a. The turf 1 also comprises a plurality of blades 3 made of a synthetic material that are connected to the mat 2. Above the face 2b of the mat 2 an infill material 10 is also provided that is arranged among the blades 3 of synthetic material.

[0113] As described in detail hereinafter, the infill material, according to the present invention, can be used both for synthetic turfs, i.e. comprising exclusively blades of synthetic material, and for hybrid turfs, i.e. comprising both blades of synthetic material and a living vegetable material.

[0114] According to the invention, the infill material 10 comprises a predetermined percentage by volume of a vegetable material consisting of rachis of cereal ear. In a possible exemplary embodiment the cereal can be maize and, therefore, the vegetable material is cob.

[0115] In the exemplary embodiment of FIG. 1, the infill material 10 provides a lower layer 11, or stabilizing infill, comprising the material consisting of rachis of cereal ear, and an upper layer 12, or performance infill, comprising a mixture of the rachis of cereal ear not coated by a layer or film of material with at least a material comprising: cereal husks, a loose final product from raw material based on ground cork, a ligninic and/or resinous material of vegetable origin, sand.

[0116] As shown in the exemplary embodiment of FIG. 2, the infill material 10 can provide a single layer. This can be completely constituted by the rachis of cereal ear which is not coated by a layer or film of material.

[0117] In another embodiment according to the invention, the infill material 10 can comprise a layer consisting of a mixture of a predetermined percentage volume of rachis of cereal ear which is not coated by a layer or film of material with a predetermined percentage volume of at least another material selected among cereal husks, a loose final product from raw material based on ground cork, a ligninic and/or resinous material of vegetable origin, sand.

[0118] In particular, the infill material 10 can be a single layer consisting of a mixture of a predetermined percentage volume of rachis of cereal ear which is not coated by a layer or film of material with a predetermined percentage volume of at least another material selected among cereal husks, a loose final product from material based on ground cork, a ligninic and/or resinous material of vegetable origin, sand.

[0119] As anticipated above, according to an embodiment of the invention, the infill material 10 can comprise a predetermined percentage by volume of a vegetable ligninic and/or resinous material i.e. having a high content of lignin and/or resin. The high content of lignin and/or resin makes these material, and therefore the infill material 10 of the whole turf, highly resistant to the attacks of microorganisms and allows, then to avoid the use of antibacterial chemical substances as provided for the turfs of prior art (see for example US2010/055461).

[0120] The presence of the ligninic and/or resinous material of vegetable origin allows in any case a slow and graduated decomposition of the material consisting of rachis of cereal ear. This is desired and appreciated, because the presence of a certain amount of microorganisms allows to reproduce a normal activity of a natural turf and allows to regenerate the turf owing to the hygienizing action that causes the elimination of the pathogenic agents and to keep nutritive substances. In order to compensate the slow degradation of the material consisting of rachis of cereal ear it is sufficient to periodically reintegrate the turf with new material. Unlike other solutions of the prior art as for example described in US2010/055461, therefore, it is essential that the material consisting of rachis of cereal ear is not coated by a film of substances that completely inhibit its natural biological activities.

[0121] The ligninic and/or resinous material, if present, can be selected from the group consisting of: a loose material based on ground coconut, olive stones, teguments of the cracked pine-kernels, material obtained by de-fibring the cones, in particular cones of arboreous species of the Pinus type, common reed, or Arundo donax, ground into fragments, or particles of predetermined size, teguments of pistachio seeds, barley grain, in particular devitalized for avoiding germination, teguments of sunflower seeds, shells of dried fruits, fragments of banana plant parts, grape seeds and/or grape stalks of Vitis vinifera, Aloe fibres, or a combination thereof. As shown, as an example in FIGS. 6A and 6B in the case of a fresh corn cob 9 that means provided with the kernels, but also valid for other types of cereal, the ligninic and/or resinous material can, advantageously, be the cap or tip cap 7 of the cereal which is the portion attaching the kernel 8 to the rachis of the cereal ear 6 and that can be separated from the kernel 8 during the treatment of the vegetable material.

[0122] In case the vegetable material is a loose product obtained from a raw material based on ground coconut, preferably it comprises the sole granular and fibrous part contained in the raw material based on the starting coconut. For example, the granular and fibrous part can be obtained undergoing the starting raw material to a separation step of the granular and fibrous part from the powder part that is present in it, as described in detail in WO2008125895. The ligninic and/or resinous material can be mixed with a predetermined percentage by volume of a raw material based on ground cork.

[0123] In particular, the above described ligninic material in the presence of humidity form a three-dimensional reticular structure that keeps between its meshes the cereal husks, trapping it and so avoiding that it can raise from the turf and scatter in the surrounding environment. This makes it possible to fully exploit the physical properties of the cereal husks, in particular its high porosity and elasticity, and to avoid at the same time that it can hamper the action of the athletes during a sports event, in case it pile up on the surface.

[0124] The infill material 10 for synthetic turfs, or hybrid turfs, as described above, is completely, even if slowly, biodegradable because it consists exclusively of organic material. This allows to avoid the disposal of the infill material in controlled dump when the synthetic turf is abandoned.

[0125] In the further exemplary embodiment, diagrammatically shown in FIG. 3, the infill material 10 provides a lower layer 11, an intermediate layer 12 and an upper layer 13. More in detail, the lower layer 11 can comprise a predetermined amount of sand, the intermediate layer 12 can comprise the material consisting of rachis of cereal ear, for example of cob, and the upper layer 13 can be constituted by a material selected among cereal husks, a loose final product from raw material based on ground cork, a ligninic and/or resinous material of vegetable origin, sand or it can be a mixture of at least two material selected among cereal husks, a loose final product from raw material based on ground cork, a ligninic and/or resinous material of vegetable origin, sand.

[0126] In the FIGS. 4 and 5 hybrid turfs, are shown, i.e. comprising both leaves of the plant species 100, i.e. deriving from the growth of at least one vegetable species, and blades of synthetic material 3, 3, in which it is used infill material 10, according to the present invention. More in detail, in case of hybrid turfs 1 a flexible support 21 is provided. This can be made, for example, of a not biodegradable material, in such a way that it can work as a barrier for roots 110 of at least one living vegetable species 100 that roots in the infill material 10. Once a predetermined vegetative development is achieved, the vegetable species 100 form a natural turf that passes in height the synthetic mat consisting of the fibres of plastic material. As shown in FIGS. 4 and 5, the difference of height Dh between the leaves of plant species 100 and the blades of synthetic material 3 can be higher than about 10 cm.

[0127] The infill material 10 can have the same compositions of the synthetic turfs described with reference to FIGS. 1 to 5. For example, the infill material 10 can comprise a lower layer 11 and an upper layer 12 as described above, with reference to FIG. 1, (FIG. 4), or a single layer as described with reference to FIG. 2, (FIG. 5).

[0128] In this case, the above described property of the cob, as well as generally of the spine of other cereals, provides an auto-regulation of the heat of the turf obtaining ideal environmental conditions for the development of the living vegetable material 100.

[0129] The support 2 can provide drainage holes 4, having sizes such that it allows the outflow of the percolated obtained by the drainage action of the infill material, but at the same time to avoid the passage of the roots.

[0130] In particular, the aforementioned vegetable material of rachis of cereal ear not coated by a layer or film of coating material, can be obtained dried or substantially dried. More in particular, the dried or substantially dried material of rachis of cereal ear not coated by a layer or film of coating material can have a moisture content less than 50%, advantageously less than 40%, preferably less than 30%, more preferably less than 20%.

[0131] It is suitable to note that the aforementioned vegetable material of rachis of cereal ear not coated by a layer or film of coating material with a moisture content less than 50% has been tested in laboratory for measuring its water absorption capacity. More precisely, an amount of 50 grams of dried or substantially dried vegetable material of rachis of cereal ear not coated, in an oven up to obtain a vegetable material with a moisture content less than 50%, precisely about 49.5%, has been introduced into a container having a diameter of 5.7 cm. Water has been added into the container giving the vegetable material the time of absorbing the same, the total weight of the added and absorbed water has been measured, and, therefore, the ratio between the weight of the vegetable material, precisely corncob, i.e. 50 g, and the weight of the added and absorbed water equal to about 98 g, i.e. the total weight of the swollen sample is 148 g. This way, the water absorption capacity of the vegetable material of rachis of cereal ear not coated by a layer or film of coating material dried or substantially dried, has been measured showing to be about 196%, which is significantly greater than 138% of the vegetable material of rachis of cereal ear not coated by a layer or film of coating material with a moisture content of about 65-70% as indicated above. Repeating the test for the same sample of dried or substantially dried vegetable material of rachis of cereal ear not coated by a layer of film of material but with a moisture content of about 30%, the water absorption capacity calculated was about 220%.

[0132] The dried or substantially dried material of rachis of cereal ear not coated by a layer or film of coating material as above described can be obtained by subjecting to an ensilage process a determined amount of vegetable material of rachis of cereal ear which is not coated by a film or layer of coating material.

[0133] In the embodiment according to the invention, which is diagrammatically shown in FIGS. 7 and 8, a determined quantity of vegetable material of rachis of cereal ear 5 with a moisture, or moisture content, greater than 60%, advantageously greater than 50%, for example greater than 40% is introduced into a silo 200, for example made of metallic, or plastic, material, advantageously by a loading duct 210.

[0134] Advantageously, as diagrammatically shown in FIG. 5, a predetermined air-flow 250 can be fed through one, or more, feeding ducts 205 within the aforementioned silo 200. The air-flow 250, preferably dried air, at a predetermined temperature, in particular higher than 20 C., more in particular higher than 25 C., advantageously higher than 40 C., preferably higher than 50 C., more preferably higher than 60 C., in such a way to cause the moisture of the vegetable material of rachis of cereal ear to decrease from the aforementioned initial moisture up to the predetermined final moisture content, in particular less than 50%, advantageously less than 40%, preferably less than 30%, more preferably less than 20%. In particular, the vegetable material of rachis of cereal ear produced in this way, is subjected to an airy drying treatment.

[0135] Advantageously, the aforementioned dried or substantially dried vegetable material of rachis of cereal ear not coated by a layer or film of coating material, at the end of the aforementioned treatment has a pH5, advantageously a pH4.5, preferably a pH4.

[0136] More in particular, a reduction of pH up to a value comprised between 4 and 5, i.e. 45 pH5, can occur, in particular following an acetic aerobics fermentation. The acidification of the environment internal to the silo leads to the development of lactic bacteria which operate the lactic fermentation, bringing the pH to values even less than 4.

[0137] In particular, the aforementioned vegetable material of rachis of cereal ear not coated by a layer or film of coating material dried or substantially dried, can be used for obtaining at least a performance infill of a turf.

[0138] In an embodiment of the invention, at least 70% in volume, advantageously at least 80% in volume, of the infill material 10 can be formed by the aforementioned dried or substantially dried vegetable material of rachis of cereal ear which is not coated by a layer or film of coating material. In an embodiment of the invention, the infill material can 10 be formed only by the aforementioned dried or substantially dried vegetable material of rachis of cereal ear not coated by a layer or film of coating material, as described above.

[0139] In particular, with reference again to FIG. 1, the infill material 10 can comprise, from below to the above, a first layer 11, or stabilizing infill, and at least a second layer 12, or performance layer, positioned above the first layer 11. This latter can comprise, or can be completely formed by, or formed for the most part, in particular at least the 70% in volume, or at least the 80% in volume, by, dried or substantially dried vegetable material of rachis of cereal ear which is not coated by a film or layer of coating material, as described above advantageously with a moisture content less than 50%, advantageously less than 40%, preferably less than 30% at the moment when the same is distributed on the second face of the mat.

[0140] The stabilizing infill 11 can be a layer of sand, in particular siliceous sand. In an alternative embodiment according to the invention, the stabilizing infill 11 can be a layer comprising a mix of sand and dried or substantially dried vegetable material of rachis of cereal ear not coated by a layer or film of coating material. For example, the aforementioned mix of the stabilizing infill can comprise between 20% and 80% in volume of sand, and between 20% and 80% in volume of dried or substantially dried vegetable material of rachis of cereal ear which is not coated by a layer or film of coating material.

[0141] The combined use of sand and dried or substantially dried vegetable material of rachis of cereal ear not coated by a layer or film of coating material, allows to obtain a turf 1 which is highly draining and because of the properties of the vegetable material of rachis of cereal ear to prevent the sand which is present in the stabilizing infill from becoming compact and, therefore, the synthetic turf owing to water irrigation or rain from flooding. In other words, the presence of the vegetable material of rachis of cereal ear guarantees the maintenance, over time, of the effectiveness of the drainage action of the layer of sand.

[0142] Furthermore, as shown in detail in FIG. 4 for the corresponding embodiment, but also valid for the other embodiments according to the invention shown in FIGS. 1 to 3, the mat or support 2 can be provided with drainage holes 4 having a size such that they allow the percolated water obtained by the drainage action of the infill material 10 to flow and leave the turf.

[0143] As shown in FIG. 9, as an example, the dried or substantially dried vegetable material of rachis of cereal ear not coated by a layer or film of coating material 6, according to the invention, having a moisture less than 50%, in particular less than 40%, advantageously less than 30%, preferably less than 20%, more preferably less than 10%, for example less than 5% can be packaged in bags 60 having predetermined capacity. In particular, each bag, or big bag 60 where the vegetable material can be stored, is made of a water impermeable material, for example polypropylene, advantageously formed by strands of polypropylene, in order to avoid that, once introduced inside of it, the vegetable material of rachis of cereal ear according to the invention, can absorb moisture from the external environment, thus assuring that the same remains at the aforementioned desired moisture content, in particular less than 50%, more in particular less than 40%, advantageously less than 30%, preferably less than 20%, more preferably less than 10%. More in particular, the displacement from the drying plant to the bag 60 can occur by an external jacket 155, for example made of nylon, which guarantees the passage of the vegetable material of rachis of cereal ear in the bag 60 without that it can absorb moisture. Therefore, at the moment of distributing the final product, that means dried or substantially dried vegetable material of rachis of cereal ear not coated by a layer or film of coating material, this will have the desired moisture content, in particular less than 50%, more in particular less than 40%, advantageously less than 30%, preferably less than 20%, more preferably less than 10%, for example less than 5%.

[0144] The dried or substantially dried vegetable material of rachis of cereal ear not coated by a layer or film of coating material, as describe above can be used as infill material 10 of a turf 1 of synthetic type (FIGS. 1 to 3), or mixed synthetic/natural (FIGS. 4 and 5), to be used both for sport and ornamental purposes.

[0145] According to the invention, the vegetable material consisting of rachis of cereal ear can be, advantageously, rounded by subjecting the vegetable material consisting of rachis of cereal ear to a rounding treatment. As diagrammatically shown in the figures from 10 to 12, the rounding treatment can be carried out by a device for carrying out the rounding treatment. For example, the aforementioned device for carrying out the rounding treatment can be a rotary drum, in particular a rotary drum sieve 300. In this latter case, the same device can carry out both a granulometry selection in order to have a material with a size comprised between 0.3 mm and 5.0 mm, by using a sieve with meshes of predetermined size, and the rounding of the treated material in order to have a rounded material. In other embodiments according to the invention, however, the selection treatment, in particular a sieving treatment, can be carried out by a first apparatus, for example a sieve, in order to select the vegetable material having a size greater than 0.3 mm, which is used in the infill material 10, and to discharge, instead, the vegetable material with a smaller size. In this case, the rounding treatment can be carried out by a second apparatus different from the first apparatus used for the selection treatment.

[0146] In the case of a rotary drum sieve 300, this can be provided with a container body 301 within which the starting aforementioned vegetable material can be introduced, for example by a loading hopper 303 guiding the same towards an inlet 304 of which the container body 301 is provided with. Within the rotary drum sieve 300, a moving device 305, for example an Archimedean screw, or an endless screw, or an element provided with a plurality of blades, can be mounted. More in detail, the moving device 305 moves the worked vegetable material of rachis of cereal ear not coated by a layer or film of coating material 5 and pushes the same against a perforated sieve 306 arranged around the same. The perforated sieve 306, for example cylindrical, or substantially cylindrical, or conical, or however tubular, shape, is provided with holes of predetermined size. During the treatment within the rotary drum sieve 300, the vegetable material of rachis of cereal ear not coated by a layer or film of coating material 5 is rounded as a result of the impact of the same against the internal wall of the sieve 306 and of the displacement caused by the moving device 305. In this way, the vegetable material of rachis of cereal ear not coated by a layer or film of coating material 5 reduces its size up to pass through the aforementioned holes 307 having predetermined size. The rounded vegetable material of rachis of cereal ear not coated by a layer or film of coating material and with reduced size 5, in particular less than the size of the holes 307, passes through the sieve 306 and exits the containing body 301 through a discharge aperture 308. The rotary drum sieve 300 can be provided with a first motor 311 adapted to cause by a first motion transmission element 312, for example a first transmission belt, the rotation about a rotational axis 310, of the displacement member 305. Furthermore, a second motor 313 can be provided configured to cause the sieve 306 to rotate about the rotation axis 310 by a second motion transmission element 314, for example a second transmission belt.

[0147] The rotary drum sieve 300 can be, furthermore, provided with an outlet, not shown in the figure for simplicity, positioned at the end portion opposite with respect to the inlet 304 and through which the vegetable material of rachis of cereal ear not coated by a layer or film of coating material 5 which is still larger than those of the holes 307 of the sieve 306 is discharged to be subjected again to a treatment. In particular, the aforementioned holes 307 of the sieve 306 can have a size comprised between 0.5 mm and 5.0 mm, advantageously comprised between 0.6 mm and 4 mm, preferably between 0.7 mm and 3.6 mm.

[0148] At the end of the rounding treatment, and, in case, at the contemporary sieving treatment, the aforementioned rounded vegetable material of rachis of cereal ear not coated by a layer or film of coating material is obtained (an enlargement of which is shown in FIG. 12). The rounded material so obtained further contribute to increase the water absorption capacity of the dried or substantially dried vegetable material of rachis of cereal ear not coated by a layer or film of coating material, in particular because the fibres made of material come closer to each other. Therefore, when the product will absorb water. Another drawback solved by the rounding treatment to which the initial vegetable material of rachis of cereal ear not coated by a layer or film of coating material is subjected to, is to avoid that the same can be damaged, in particular cut, due to the presence of cutting edges or contours, the fibres made of synthetic material of the turf to which it is destined to.

[0149] As diagrammatically shown in FIG. 12, the rounded vegetable material of rachis of cereal ear not coated by a layer or film of coating material 5, in case having the aforementioned selected granulometry, for example comprised between 0.3 mm and mm, 5 advantageously comprised between 0.5 mm e 5 mm, exiting the device for carrying out the rounding treatment 300, can be sent to the aforementioned drying step, advantageously to the aforementioned ensilage step and, therefore, fed to the aforementioned silo 200.

[0150] In particular, the vegetable material of rachis of cereal ear not coated by a layer or film of coating material, advantageously rounded, has a bulk density comprised between 0.3 kg/dm.sup.3 and 0.5 kg/dm.sup.3, preferably between 0.35 kg/dm.sup.3 and 0.55 kg/dm.sup.3.

[0151] The dried or at least partly dried and rounded vegetable material of rachis of cereal ear, to be precise corn cob, not coated by a film or layer of coating material 6, has been tested in laboratory by using a container, where a quantity of about 50 grams of dried or substantially dried and rounded vegetable material of rachis of cereal ear not coated by a layer or film of coating material 6, with an initial moisture, or moisture content, less than 50% and precisely about 49.6%, has been introduced. Adding water into the container and giving the vegetable material of rachis of cereal ear 6 the time of absorbing the same, the total weight of the absorbed water has been resulted to be equal to 128 g, i.e. the total weight of the swollen sample was 178 g and, therefore, the water absorption capacity of this vegetable material 6 is greater than 256%. Repeating the test for a moisture content less than 30%, and precisely about 29.5%, the total weight of the absorbed water has been resulted to be equal to 152 g, i.e. the total weight of the swollen sample was 202 g and, therefore, the calculated water absorption capacity of this vegetable material 6 was about 304%. It has, therefore, been concluded that the vegetable material 6 obtained at the end of the rounding process described above has a water absorption capacity significatively higher than that of the dried or substantially dried vegetable material 6 described above with the same moisture content (about 50% and about 30%) but not rounded.

[0152] The vegetable material of rachis of cereal ear not coated by a layer or film of coating material dried or partly dried and rounded 6 obtained by subjecting the material both to the rounding treatment and to the drying treatment as described above, can be introduced within the bags 60. In particular, the vegetable material of rachis of cereal ear not coated by a layer or film of coating material, in case rounded and/or dried or substantially dried, contained within the bag 60 remains at the same, or substantially the same, predetermined moisture content indicated above, for example less than 50%, in particular less than 40%, advantageously less than 30%, preferably less than 20%, more preferably less than 10%, during its transportation from the production site up to its distribution on the second face of the mat 2 for obtaining the turf 1 at the use site.

[0153] The foregoing description of an embodiment of the method and of the apparatus according to the invention will so fully reveal the invention according to the conceptual point of view so that other, by applying current knowledge, will be able to modify and/or adapt in various applications this specific embodiment without further research and without parting from the invention, and, accordingly, it is meant that such adaptations and modifications will have to be considered as equivalent to the exemplified specific embodiment. The means and the materials to realise the different functions described herein could have a different nature without, for this reason, departing from the field of the invention. It is to be understood that the phraseology or terminology that is employed herein is for the purpose of description and not of limitation.