FR2848577A1 - PROCESS FOR TREATING NATURAL PLANT FIBERS, IN PARTICULAR WITH A VIEW TO THE USE OF SUCH FIBERS FOR INSULATING BUILDINGS - Google Patents

Abstract

Method involves passing them through a separator (1) for aeration, followed by a tunnel (3) for treating them with various liquids as they are turned inside rotary drums (5). The tunnel has compartments (6-10) for washing fibres/feathers, fire-proofed with boron and ammonium salts, and given anti-parasite treatment. Method involves passing them through a separator (1) for aeration, followed by a tunnel (3) for treating them with various liquids as they are turned inside rotary drums (5). The tunnel has compartments (6-10) for washing fibres/feathers, fire-proofed with boron and ammonium salts, given anti-parasite treatment, optionally perfumed with cedarwood/lavender essences, waterproofed and marked for traceability. After the tunnel they go to a rinsing (11)/membrane pressing (12) unit, followed by tumble drying (14) in hot air before a storage unit (16), a second separator (17) and a packing unit (18). The finished product can be used as insulation at a rate of 3.5 - 4 kg/sq m to give a thickness of 20 cm.

Description

The present invention is in the field of plant fiber treatment

  natural, such as cotton, linen, hemp or the like. It relates to a process for treating such natural plant fibers, with a view in particular to the manufacture of an insulation product for the

  building. The use of an insulating product based on natural plant fibers is known in the building sector. For example, it is known to apply by spraying onto a surface a product combining a binder and such fibers, or also to manufacture insulating panels comprising at least one layer of these fibers.

  A general problem posed lies in the treatment of fibers with a view to obtaining such insulating products. In particular, it is necessary to give the fibers an adequate consistency, as well as flame retardant and anti-parasitic qualities. It will be noted at this stage of the description that it is known to package the bale fibers after their treatment, with a view to their subsequent use. More particularly, it is known to treat the fibers on the one hand with boron salts and / or ammonium salts, to give them a flame retardant character, and on the other hand with carbonic acid to give them an antiparasitic character. , fungicide and insecticide in particular.

  The known processes of the prior art are usually long to implement, that is to say of the order of 24 hours for a treatment of 300 kg of fibers. The factors for increasing the duration of treatment reside in particular in the physico-chemical treatment of the fibers by bath. Furthermore, there is the problem of routing fibers from one treatment station to another, and more particularly of a continuous chain arrangement of the treatment of fibers, from a gross mass of fibers to their packaging. in ball.

  There is therefore a problem to be solved, which lies in the organization of a manufacturing process making it possible to carry out the continuous fiber processing operations in a continuous chain and in the shortest possible time.

  It follows that a difficulty to be overcome in order to resolve this problem is to reconcile the different stages of fiber treatment, based on intuitive compromises between the means used and the results obtained, both specifically for each of these stages 5 as a whole from the treatment of fibers in the gross mass state to their conditioning in bales.

  The object of the present invention is therefore to propose a process for the continuous chain treatment of natural plant fibers, such as cotton, linen, hemp or the like, with a view to their use for the insulation of buildings, which offers a compromise between the various constraints mentioned above. More particularly, it is the object of the present invention to reduce the time necessary for the implementation of such a method, in particular with regard to the operations of washing and physicochemical treatment of the fibers, and with regard to the time elapsed. between the physico-chemical treatments of the fibers and their conditioning in bales. It is even more particularly targeted by the present invention to propose such a method in which the operations of transferring fibers from one station to another are simplified.

  The process of the invention generally comprises in particular the successive stages consisting in: a) a first mechanical treatment of the fibers for their aeration, b) a treatment for washing the fibers, c) physico-chemical treatments of the fibers with treating liquids. These physico-chemical treatments notably consist in wetting the fibers with the treating liquids. These treating liquids comprise, in specific wetting operations, on the one hand mineral salts or the like, such as boron and / or ammonium salts, with a view to giving them flame-retardant qualities, and on the other hand with acids or the like, carbonic acid in particular, with a view to giving them anti-parasitic qualities, d) a second mechanical treatment of the fibers for their conditioning in bales.

  The method of the invention is mainly recognizable in that it consists in circulating the fibers in a liquid fiber processing tunnel. Staged stations for respective treatment of the fibers with a liquid containing a specific treating agent are provided inside this treatment tunnel. Each station implements a capacity for receiving the fibers and the corresponding treating agent, this capacity being rotatably mounted on itself for the purpose of applying the treatment by oscillating stirring of the fibers wetted by the treating liquid. Each capacity is selectively communicating with the rotating capacity of a neighboring station, for the transfer of the fibers from one to the other of the step processing stations of the processing tunnel. These arrangements are such that the various liquid treatment operations of the fibers are carried out by stirring the latter wetted by the treating liquid. Furthermore, the transfer of the fibers from one treatment station to another in the treatment tunnel is carried out continuously after each of the treatments, by spilling the fibers from one of the capacities. It will be noted that the liquid treatment stations of the treatment tunnel are for example any one at least, preferably in successive order, of a washing station, a fire-retardant treatment station, a station anti-parasite, fungicide and / or insecticide treatment in particular, a perfuming treatment station, a waterproofing treatment station, and a marking treatment station by incorporating a tracer agent into the fibers. Preferably and in combination with the abovementioned provisions, the method proposed by the invention further comprises the steps consisting, at the outlet of the treatment tunnel, in extracting the liquids from the fibers. This extraction is preferably carried out by a first mechanical operation of packing the fibers and a second operation of drying the fibers with hot air by passing them through a dryer. Then, in a following step, the fibers circulate in a frayer prior to their packaging, in particular in bales.

  According to a first variant, the fiber packing operation is carried out by means of a rotary wringer at variable speed. It will be noted that this wringer is advantageously in selective communication with the rotating capacity of the terminal station of the processing tunnel. According to a second variant, the fiber packing operation is carried out by means of a membrane press, comprising a fiber receiving tank arranged in the form of a piston body. Like the arrangements of the previous variant, this tank is advantageously in selective communication with the rotating capacity of the terminal station of the processing tunnel. It will be noted that this variant is preferred over the previous one, on the one hand to avoid the formation of fiber fluff by their passage inside the wringer, and on the other hand by the ease offered of transfer of the fibers. at the outlet of the liquid extraction station, the masses of fibers to be conveyed at the outlet of the membrane press being in particular shaped into wafers.

  Preferably, a storage station, formed in particular of a silo, is interposed between the dryer and the shredder, at the outlet of which the storage station is arranged the latter.

  According to an advantageous embodiment of the capacity of each of the treatment stations of the treatment tunnel, this comprises at least one intake and / or discharge outlet for the fibers. It will be understood that, according to various variants, these mouths can be separate or confused. The capacity is also equipped with means for the admission and evacuation of the treating liquids, in particular through the openings which it comprises. From such an advantageous arrangement of the capacities, the method of the invention comprises the specific operations consisting, in each of the treatment stations of the treatment tunnel, successively in: *) orienting the capacity by pivoting on itself to receive the fibers by pouring through the inlet mouth, *) swinging on itself the capacity for stirring the fibers, at least later, if not also simultaneously with the introduction of the treating liquids, *) orient at the end of treatment the capacity by turning over on itself until the disposal mouth is available above the intake mouth of the capacity of the neighboring station, with a view to the spillage of the fibers inside the latter. The provisions of the invention make it possible in particular to apply a duration of treatment to the fibers inside each treatment station of the treatment tunnel, of the order of between 2 minutes and 10 minutes at a temperature of the treatment liquid. order between 300C and 600C.

  It will be noted that according to a preferred form of implementation of the method of the invention, the routing of the fibers between the first mechanical fiber treatment station for their aeration, by their passage through a first frayer for example, towards the tunnel treatment, then to the drying station, then to the storage station, then to the packaging station, are respectively carried out by means of conveyor belts. Such means for transferring fibers from one station to another have the advantage of allowing their spontaneous routing at the end of their passage to each of these stations, without requiring any particular manipulation.

  The present invention will be better understood, and details will become apparent from the description which will be made of a preferred embodiment thereof, in relation to the figure of the appended plate which schematically illustrates a process of the invention.

  In the figure, a process for treating natural plant fibers, with a view to their use for insulating buildings, generally comprises the successive steps consisting in: *) treating the fibers with a first frayer 1 for their aeration. This operation is more particularly aimed at refining and thinning the fibers, and giving them a suitable tangle for their use as an insulating material. *) route the fibers, in particular through a first conveyor belt 2, to a fiber processing tunnel 3 with treatment liquids, such as 4.

  *) treat the fibers by their oscillating stirring, or the like or even by their rotating stirring, together with their wetting by the treating liquids 4. This treatment is carried out at a temperature of the order of between 300C and 600C for a period of between 2mn and 10 minutes, successively within respective 5 rotating capacities, such as 5, assigned to a respective processing. It will be noted that these capacities are preferably successively aligned, having their geometric axis A of rotation substantially coincident. The treatment tunnel 3 comprises at least any one of respective washing stations 6, flame retardant treatment 7, anti-parasitic treatment 8, or also also perfuming treatment 9, waterproofing treatment and marking treatment 10 with a tracer, attesting to the origin of the treatment of the fibers.

  *) extract liquids from the fibers by packing and drying with hot air.

  According to two possible variants, this packing is carried out either by a wringer 11, or and preferably by a membrane press 12. A second conveyor belt 13 is placed at the outlet of the packing station 11 or 12, to route the fibers to a hot air dryer 14.

  *) conveying the fibers at the outlet of the dryer 14, by a third conveyor belt 15 in particular, to a storage station 16, at the outlet of which a second frayer 17 is arranged.

  *) route the fibers, by a fourth conveyor belt 18 in particular, to a station 19 for conditioning the fibers, preferably in bales by means of a press.

Claims (9)

  1.- Process for the treatment of natural plant fibers, with a view in particular to the use of these fibers for the insulation of buildings, of the type of process comprising the successive stages: a) of a first mechanical treatment of the fibers for their aeration, b) washing the fibers, c) physicochemical treatment of the fibers with treating liquids, on the one hand with mineral salts or the like with a view to imparting them flame retardant qualities, and on the other hand with acids in order to give them anti-parasitic qualities, d) a second mechanical treatment of the fibers for their baling, characterized in that it consists in circulating the fibers in a tunnel (3) for liquid treatment of fibers, inside which are arranged staged stations (6-10) for respective treatment of the fibers with a liquid (4) containing a specific treating agent, each station (6-10) employing a capacity (5) of reception fibers and the corresponding treating agent, this capacity (5) being rotatably mounted on itself for the application of the treatment by oscillating stirring of fibers wetted by the treating liquid (4), and being selectively communicating with the capacity rotating (5) from a neighboring station for the transfer of fibers from one to the other of the stepped treatment stations (6-10) of the treatment tunnel (3), so that the various liquid treatment operations (4) fibers are made by stirring the latter wetted by the treating liquid (4), and that the transfer of the fibers from one treatment station (6-10) to another of the treatment tunnel (3), either performed continuously at the end of each of the treatments, by pouring the fibers from one of the capacities to the other (5).   2. A method of treating fibers according to claim 1, characterized: in that the stations (6-10) for liquid treatment of the treatment tunnel (3) are any at least one washing station (6) , a flame retardant treatment station (7), an anti-parasitic treatment station (8), a perfuming treatment station (9), a waterproofing treatment station (10), and d '' a marking treatment station by incorporating a tracer agent into the fibers.   3. A method of treating fibers according to any one of the preceding claims, characterized: in that it comprises the steps consisting, at the outlet of the treatment tunnel (3), in extracting the liquids from the fibers by a first mechanical operation of packing the fibers and a second operation of drying the fibers with hot air by passing them through a drier (14), then in a following step in circulating the fibers in a frayer (17) prior to their conditioning.   4. A method of treating fibers according to claim 3, characterized: in that the fiber packing operation is carried out by means of a rotary wringer (11) at variable speed in selective communication with the rotating capacity (5 ) of the terminal station (10) of the processing tunnel (3).   5. A method of treating fibers according to claim 3, characterized: in that the fiber packing operation is carried out by means of a membrane press (12), comprising a tank for receiving the fibers arranged in the body of piston.   6. A method of treating fibers according to claim 3, characterized: in that a storage station (16) is interposed between the dryer (14) and the shredder (17), at the outlet of which storage station (16 ) is arranged the latter (17).   7. A method of treating fibers according to any one of the preceding claims, characterized: in that the capacity (5) of each of the treatment stations (6-10) of the treatment tunnel (3) comprising at least one 5 fiber inlet and / or outlet mouth, and being equipped with means for inlet and outlet of the treating liquids (4), the method comprises the specific operations consisting, in each of the treatment stations (6-10 ) from the treatment tunnel (3), successively to *) orient the capacity (5) by pivoting on itself to receive the 10 fibers by pouring through the intake mouth, *) swinging the capacity on itself (5) for the stirring of the fibers, at least later, if not also simultaneously with the introduction of the treating liquids (4), *) orient the capacity (5) by turning it over on itself 15 at the end of the treatment until provision from the drain outlet above the ad outlet capacity mission (5) of the neighboring substation, with a view to spilling the fibers inside the latter (5).   8. A method of treating fibers according to any one of the preceding claims, characterized: in that the duration of treatment of the fibers inside each treatment station (6-10) of the treatment tunnel (3) is of the order of between 2 minutes and 10 minutes at a temperature of the treatment liquid (4) of the order of between 30 ° C. and 60 ° C. 25 9. A method of treating fibers according to claim 6, characterized: in that the fibers are routed between the first mechanical treatment station (1) of the fibers for their aeration towards the treatment tunnel (3), then towards the drying station (14), then to the storage station (16), then to the packaging station (19), are respectively carried out by means of conveyor belts (2,13,15,18).   10.- A method of treating fibers according to any one of the preceding claims, characterized: in that it comprises the successive steps consisting in: *) treating the fibers with a first frayer (1) for their aeration, * ) route the fibers to a processing tunnel (3) for the fibers with treating liquids (4), *) treat the fibers by mixing them together with their wetting by the treating liquids (4), at a temperature of the order of between 30'C and 10 600C for a period of between 2mn and 10mn, successively within respective revolving capacities (5), in at least any one of respective washing stations (6), of flame retardant treatment (7) , anti-parasitic treatment (8), or even also perfume treatment (9), waterproofing treatment (10) and marking treatment, *) extract the liquids from the fibers by packing and drying them with hot air, * ) route the fibers to a post e storage (16), at the outlet of which a second frayer (17) is arranged, *) conveying the fibers to a fiber conditioning station (19).