Method for dry-forming a cellulose product from cellulose fibres in a product forming unit and a product forming unit

Abstract

A product forming unit and method for dry-forming a three-dimensional cellulose product from cellulose fibres. The product forming unit comprises a fibre transporting unit and a forming mould. The fibre transporting unit is configured for feeding loose and separated cellulose fibres from the fibre transporting unit to a three-dimensional shaping structure by means of a flow of air as carrying medium for the cellulose fibres. The loose and separated cellulose fibres are arranged onto a three-dimensional surface of the three-dimensional shaping structure by means of the flow of air for air-forming a three-dimensional body of cellulose fibres. The three-dimensional surface of the three-dimensional shaping structure has a shape corresponding to a shape of a three-dimensional pressing surface of the forming mould. The forming mould is configured for dry-forming the cellulose product into a three-dimensional compressed structure in a pressing operation from the three-dimensional body of cellulose fibres, by pressing and heating the three-dimensional shaping structure with the three-dimensional body of cellulose fibres with a forming pressure and a forming temperature.

Description

[0001] METHOD FOR DRY-FORMING A CELLULOSE PRODUCT FROM CELLULOSE

[0002] FIBRES IN A PRODUCT FORMING UNIT AND A PRODUCT FORMING UNIT

[0003] TECHNICAL FIELD

[0004] The present disclosure relates to a method for dry-forming a cellulose product from cellulose fibres in a product forming unit. The disclosure further relates to a product forming unit for dry-forming a cellulose product from cellulose fibres.

[0005] BACKGROUND

[0006] Cellulose fibres are commonly used as raw material for producing or manufacturing cellulose products. Products formed of cellulose fibres can be used in many different situations where there is a need for sustainable products. A wide range of products can be produced from cellulose fibres, such as for example bottles, cups, and containers.

[0007] Product forming units are used when manufacturing cellulose products from raw materials including cellulose fibres, and traditionally cellulose products have been produced by wet-forming methods. One material commonly used for wet-forming cellulose fibre products is wet moulded pulp. Wet-formed products are generally formed by immersing a suction forming mould into a liquid or semi liquid pulp suspension or slurry comprising cellulose fibres, and when suction is applied, a body of pulp is formed with the shape of the desired product by fibre deposition onto the forming mould. With all wet-forming methods, there is a need for drying of the wet moulded product, where the drying process is a time and energy consuming part of the production. The demands on aesthetical, chemical and mechanical properties of cellulose products are increasing, and due to the properties of wet-formed cellulose products, the mechanical strength, flexibility, freedom in material thickness, and chemical properties are limited. It is also difficult in wet-forming processes to control the mechanical properties of the products with high precision. One development in the field of producing cellulose products, is dry-forming of cellulose products without using wet-forming methods. Instead of forming the cellulose products from a liquid or semi liquid pulp suspension or slurry, a cellulose structure air-formed from cellulose fibres is used. The cellulose structure is inserted into a forming mould and during the dry-forming of the cellulose products, the cellulose fibres are subjected to a high forming pressure and a high forming temperature. One difficulty with dry-forming methods is the problem with an efficient production process, where deep drawn cellulose products can be produced at high speeds with high quality. The air-forming and handling of the cellulose structure is a complicated and time consuming process when dry-forming the cellulose products, and there is a need for producing products with high finish at increased production rates. Thus, a more efficient product forming unit and method for producing high-quality cellulose products are desired, especially when forming deep drawn products.

[0008] SUMMARY

[0009] An object of the present disclosure is to provide a method for dry-forming a three- dimensional cellulose product from cellulose fibres in a product forming unit, and a product forming unit for dry-forming a cellulose product from cellulose fibres, where the previously mentioned problems are avoided. This object is at least partly achieved by the features of the independent claims. The dependent claims contain further developments of the method for dry-forming a cellulose product and the product forming unit for dry-forming a cellulose product.

[0010] The disclosure concerns a method for dry-forming a three-dimensional cellulose product from cellulose fibres in a product forming unit. The product forming unit comprises a fibre transporting unit and a forming mould. The method comprises the steps: providing loose and separated cellulose fibres to the fibre transporting unit, and feeding the loose and separated cellulose fibres in the fibre transporting unit by means of a flow of air; feeding of the loose and separated cellulose fibres from the fibre transporting unit to a three-dimensional shaping structure by means of the flow of air as carrying medium for the cellulose fibres, and arranging the loose and separated cellulose fibres onto a three-dimensional surface of the three-dimensional shaping structure by means of the flow of air for air-forming a three-dimensional body of cellulose fibres, wherein the three-dimensional surface of the three-dimensional shaping structure has a shape corresponding to a shape of a three-dimensional pressing surface of the forming mould; positioning the three-dimensional shaping structure with the air-formed three-dimensional body of cellulose fibres in the forming mould; dry-forming the cellulose product into a three-dimensional compressed structure in a pressing operation from the three-dimensional body of cellulose fibres, by pressing and heating the three-dimensional shaping structure with the three- dimensional body of cellulose fibres in the forming mould with a forming pressure and a forming temperature.

[0011] Advantages with these features are that the process of forming the cellulose product can be more efficient, where the cellulose product can be produced at high speeds with high quality by shaping the three-dimensional body of cellulose fibres before dryforming the cellulose product into the three-dimensional compressed structure in the forming mould. The handling of the cellulose fibres is simplified with the at least one three-dimensional body of cellulose fibres, and the method is enabling the dry-forming of cellulose products with high finish at high production rates. The three-dimensional shaping structure is enabling a more efficient product forming unit and method for producing high-quality cellulose products, which especially is suitable for forming deep drawn products. The three-dimensional surface of the three-dimensional shaping structure is defined as a non-planar surface having a three-dimensional shape for an efficient forming of the three-dimensional body of cellulose fibres. The three-dimensional surface has a surface configuration adapted to the configuration of the forming mould for an efficient positioning of the three-dimensional body of cellulose fibres and the three-dimensional shaping structure in the forming mould. The three-dimensional surface of the three-dimensional shaping structure may have any suitable three-dimensional configuration. Suitably, the three-dimensional surface has a shape corresponding to or similar to a final shape of the cellulose product formed in the forming mould. In this way, the shape of the three-dimensional body of cellulose fibres suitably has a shape corresponding to or similar to a final shape of the cellulose product formed in the forming mould. The three-dimensional surface of the three- dimensional shaping structure has a shape corresponding to the shape of the three- dimensional pressing surface of the forming mould for an efficient forming process. This is for example desired if deep drawn products are formed. With the expression corresponding shape is meant that the three-dimensional surface of the three- dimensional shaping structure and at least one three-dimensional pressing surface of the forming mould, have three-dimensional shapes that are similar in configuration, resulting in the forming of a three-dimensional body of cellulose fibres that fits in the forming mould without large deformations. It should be understood that the three- dimensional surface of the three-dimensional shaping structure and at least one three-dimensional pressing surface of the forming mould may or may not be identical, but at least arranged with corresponding three-dimensional shapes for an efficient positioning of the three-dimensional body of cellulose fibres in the forming mould together with the three-dimensional shaping structure.

[0012] In one embodiment, the forming pressure is in the range of 1-600 MPa, preferably in the range of 1-100 MPa, more preferably in the range of 4-20 MPa, and the forming temperature is in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C. These parameters are enabling an efficient forming of the cellulose products into the three-dimensional compressed structure, where the cellulose products can be formed with a high rigidity.

[0013] In one embodiment, the three-dimensional shaping structure comprises an outer surface and an inner surface. The three-dimensional surface is arranged as the outer surface and / or the inner surface. The three-dimensional shaping structure comprises a plurality of suction openings connecting the outer surface and the inner surface. The method further comprises the steps: arranging the loose and separated cellulose fibres onto the three-dimensional surface by means of the flow of air for air-forming the three-dimensional body of cellulose fibres, and applying a negative pressure via the suction openings for distributing the cellulose fibres onto the three-dimensional surface. The suction openings are enabling efficient deposition of the cellulose fibres onto the three-dimensional surface of the three-dimensional shaping structure, and the negative pressure applied is securing a desired distribution of the cellulose fibres. The suction openings may have any suitable shape, size and configuration. The shape and / or size of the suction openings may vary between different parts of the three-dimensional shaping structure, as well as the number of suction openings arranged in the three-dimensional shaping structure.

[0014] In one embodiment, the method further comprises the step: dry-forming the cellulose product in the forming mould from the three-dimensional body of cellulose fibres in the pressing operation, where during dry-forming the three-dimensional shaping structure is supporting the three-dimensional body of cellulose fibres, and where the cellulose fibres in the three-dimensional body of cellulose fibres are integrated into the three-dimensional compressed structure. The cellulose product is formed from the three-dimensional body of cellulose fibres. The cellulose fibres in the three- dimensional body of cellulose fibres are compressed and integrated into the three- dimensional compressed structure during the pressing operation. The three- dimensional shaping structure is used as a structural element supporting the three- dimensional body of cellulose fibres during the pressing operation for an efficient forming of the cellulose product.

[0015] In one embodiment, the method further comprises the steps: removing the three- dimensional compressed structure and the three-dimensional shaping structure from the forming mould after the pressing operation; and separating the three-dimensional compressed structure from the three-dimensional shaping structure.

[0016] In one embodiment, the three-dimensional shaping structure is arranged as a three- dimensional net structure or as a three-dimensional perforated structure. These constructions are providing an efficient distribution of cellulose fibres onto the three- dimensional surface, while allowing the flow of air to pass through the three- dimensional shaping structure.

[0017] In one embodiment, the forming mould comprises a first mould part and a corresponding second mould part. The first mould part and / or the second mould part comprises the three-dimensional pressing surface. The method further comprises the steps: arranging the three-dimensional shaping structure with the air-formed three- dimensional body of cellulose fibres into a position between the first mould part and corresponding second mould part; applying the forming pressure by pressing the three-dimensional shaping structure with the air-formed three-dimensional body of cellulose fibres between the first mould part and corresponding second mould part; and applying the forming temperature onto the three-dimensional shaping structure with the air-formed three-dimensional body of cellulose fibres in the forming mould. The first mould part is cooperating with the second mould part, and the first mould part and second mould part are interacting for efficiently forming the cellulose product into the three-dimensional compressed structure. In one embodiment, the method further comprises the step: compacting the three- dimensional body of cellulose fibres before dry-forming the cellulose product in the forming mould. By compacting the three-dimensional body of cellulose fibres before dry-forming the cellulose product in the forming mould, the three-dimensional body of cellulose fibres is easier to transport to the forming mould. The compacting operation is compressing the fibre structure of the three-dimensional body of cellulose fibres into a more dense structure, without influencing the general three-dimensional shape.

[0018] The disclosure further concerns a product forming unit for dry-forming a three- dimensional cellulose product from cellulose fibres. The product forming unit comprises a fibre transporting unit and a forming mould. The fibre transporting unit is configured for feeding loose and separated cellulose fibres from the fibre transporting unit to a three-dimensional shaping structure by means of a flow of air as carrying medium for the cellulose fibres. The loose and separated cellulose fibres are arranged onto a three-dimensional surface of the three-dimensional shaping structure by means of the flow of air for air-forming a three-dimensional body of cellulose fibres. The three-dimensional surface of the three-dimensional shaping structure has a shape corresponding to a shape of a three-dimensional pressing surface of the forming mould. The forming mould is configured for dry-forming the cellulose product into a three-dimensional compressed structure in a pressing operation from the three- dimensional body of cellulose fibres, by pressing and heating the three-dimensional shaping structure with the three-dimensional body of cellulose fibres with a forming pressure and a forming temperature.

[0019] Advantages with these features are that the process of forming the cellulose product in the product forming unit can be more efficient, where the cellulose product can be produced at high speeds with high quality by shaping the three-dimensional body of cellulose fibres before dry-forming the cellulose product into the three-dimensional compressed structure in the forming mould. The handling of the cellulose fibres is simplified with the at least one three-dimensional body of cellulose fibres, and the method is enabling the dry-forming of cellulose products with high finish at high production rates. The three-dimensional shaping structure is enabling a more efficient product forming unit for producing high-quality cellulose products, which especially is suitable for forming deep drawn products. The three-dimensional surface of the three- dimensional shaping structure is defined as a non-planar surface having a three- dimensional shape for an efficient forming of the three-dimensional body of cellulose fibres. The three-dimensional surface has a surface configuration adapted to the configuration of the forming mould for an efficient positioning of the three-dimensional body of cellulose fibres and the three-dimensional shaping structure in the forming mould. The three-dimensional surface of the three-dimensional shaping structure may have any suitable three-dimensional configuration. Suitably, the three-dimensional surface has a shape corresponding to or similar to a final shape of the cellulose product formed in the forming mould. In this way, the shape of the three-dimensional body of cellulose fibres suitably has a shape corresponding to or similar to a final shape of the cellulose product formed in the forming mould. The three-dimensional surface of the three-dimensional shaping structure has a shape corresponding to the shape of the three-dimensional pressing surface of the forming mould for an efficient forming process. This is for example desired if deep drawn products are formed. With the expression corresponding shape is meant that the three-dimensional surface of the three-dimensional shaping structure and at least one three-dimensional pressing surface of the forming mould, have three-dimensional shapes that are similar in configuration, resulting in the forming of a three-dimensional body of cellulose fibres that fits in the forming mould without large deformations. It should be understood that the three-dimensional surface of the three-dimensional shaping structure and at least one three-dimensional pressing surface of the forming mould may or may not be identical, but at least arranged with corresponding three-dimensional shapes for an efficient positioning of the three-dimensional body of cellulose fibres in the forming mould together with the three-dimensional shaping structure.

[0020] In one embodiment, the forming pressure is in the range of 1-600 MPa, preferably in the range of 1-100 MPa, more preferably in the range of 4-20 MPa, and the forming temperature is in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C. These parameters are enabling an efficient forming of the cellulose products into the three-dimensional compressed structure, where the cellulose products can be formed with a high rigidity.

[0021] In one embodiment, the three-dimensional shaping structure comprises an outer surface and an inner surface. The three-dimensional surface is arranged as the outer surface and / or the inner surface. The three-dimensional shaping structure comprises a plurality of suction openings connecting the outer surface and the inner surface. The suction openings are enabling efficient deposition of the cellulose fibres onto the three-dimensional surface, and when applying a negative pressure a desired distribution of the cellulose fibres is enabled. The suction openings may have any suitable shape, size and configuration. The shape and / or size of the suction openings may vary between different parts of the three-dimensional shaping structure, as well as the number of suction openings arranged in the three-dimensional shaping structure.

[0022] In one embodiment, the forming mould is configured for dry-forming the cellulose product from the three-dimensional body of cellulose fibres in the pressing operation. The three-dimensional shaping structure is configured for supporting the three- dimensional body of cellulose fibres, and the cellulose fibres in the three-dimensional body of cellulose fibres are integrated into the three-dimensional compressed structure. In this embodiment, the cellulose product is formed from the three- dimensional body of cellulose fibres. The cellulose fibres in the three-dimensional body of cellulose fibres are compressed and integrated into the three-dimensional compressed structure during the pressing operation. The three-dimensional shaping structure is used as a structural element supporting the three-dimensional body of cellulose fibres during the pressing operation for an efficient forming of the cellulose product.

[0023] In one embodiment, the three-dimensional shaping structure is arranged as a three- dimensional net structure or as a three-dimensional perforated structure. These constructions are providing an efficient distribution of cellulose fibres onto the three- dimensional surface, while allowing the flow of air to pass through the three- dimensional shaping structure.

[0024] In one embodiment, the forming mould comprises a first mould part and a corresponding second mould part. The first mould part and / or the second mould part comprises the three-dimensional pressing surface. The forming mould is configured for applying the forming pressure by pressing the three-dimensional shaping structure with the air-formed three-dimensional body of cellulose fibres between the first mould part and corresponding second mould part. The forming mould is configured for applying the forming temperature onto the three-dimensional shaping structure with the air-formed three-dimensional body of cellulose fibres. The first mould part is cooperating with the second mould part, and the first mould part and second mould part are interacting for efficiently forming the cellulose product into the three- dimensional compressed structure.

[0025] BRIEF DESCRIPTION OF DRAWINGS

[0026] The disclosure will be described in detail in the following, with reference to the attached drawings, in which

[0027] Fig. 1a-f show schematically, in side views, an embodiment of a product forming unit comprising a fibre transporting unit and a forming mould, where a three-dimensional shaping structure is arranged on a support structure,

[0028] Fig. 2a-b show schematically, in perspective views from above, the three- dimensional shaping structure and an alternative embodiment of the three-dimensional shaping structure, and

[0029] Fig. 3a-h show schematically, in side views, an embodiment of a product forming unit comprising a fibre transporting unit and a forming mould, where a three-dimensional shaping structure is arranged on a movable support structure.

[0030] DESCRIPTION OF EXAMPLE EMBODIMENTS

[0031] Various aspects of the disclosure will hereinafter be described in conjunction with the appended drawings to illustrate and not to limit the disclosure, wherein like designations denote like elements, and variations of the described aspects are not restricted to the specifically shown embodiments, but are applicable on other variations of the disclosure.

[0032] In the figures, different embodiments of a product forming unit II are schematically illustrated, in which a cellulose product 1 is dry-formed from cellulose fibres CF. The product forming unit II comprises a fibre transporting unit T and a forming mould M. The fibre transporting unit T is used for feeding loose and separated cellulose fibres CF into a flow of air A, and for transporting the cellulose fibres CF from the fibre transporting unit T to a three-dimensional shaping structure S by means of the flow of air A as carrying medium for the cellulose fibres CF. The loose and separated cellulose fibres are arranged onto a three-dimensional surface SSD of the three- dimensional shaping structure S by means of the flow of air A for air-forming a three- dimensional body B of cellulose fibres CF. The cellulose product 1 is dry-formed into a three-dimensional compressed structure CSD in a pressing operation OP from the three-dimensional body B of cellulose fibres CF, by pressing and heating the three- dimensional shaping structure S with the three-dimensional body B of cellulose fibres CF in the forming mould M with a forming pressure Pp and a forming temperature Tp. During dry-forming, the cellulose fibres CF in the three-dimensional body B of cellulose fibres CF are integrated into the three-dimensional compressed structure C3D.

[0033] With the expression cellulose product 1 is meant a product that is dry-formed in the forming mould M from the cellulose fibres CF. The dry-formed cellulose product 1 may be a final product ready for use in a specific application. Alternatively, the dry-formed cellulose product 1 may be a pre-formed part of a final product and thus constitute a part of an assembled final product. One or more pre-formed parts may for example be attached to each other with glue or other fastening means into a final product.

[0034] With the expression loose and separated cellulose fibres CF is meant cellulose fibres that are separated from each other and loosely arranged relative to each other, or cellulose fibres or cellulose fibre bundles that are separated from each other and loosely arranged relative to each other.

[0035] The cellulose fibres CF may originate from a suitable cellulose raw material, such as a pulp material. Suitable pulp materials are for example fluff pulp, paper structures, or other cellulose fibre containing structures. The cellulose fibres may also be extracted from agricultural waste materials, for example wheat straws, fruit and vegetable peels, bagasse, or from other suitable sources. When for example using pulp as raw material for the cellulose fibres CF, the pulp structure commonly needs to be separated in a separating unit, such as a suitable mill unit, before feeding the loose and separated cellulose fibres CF into the flow of air A. In the separating unit, the pulp structure is separated into individual cellulose fibres, or into individual cellulose fibres and cellulose fibre bundles, and the better milling process the more individual cellulose fibres are formed. In other embodiments, only individual cellulose fibres may be used as raw material. The loose and separated cellulose fibres CF may be provided by a mill unit arranged in connection to the product forming unit II, or alternatively preprepared loose and separated cellulose fibres CF are provided to the product forming unit II.

[0036] The fibre transporting unit T is used for arranging the loose and separated cellulose fibres CF onto the three-dimensional surface SSD of the three-dimensional shaping structure S by means of the flow of air A for forming the three-dimensional body B of cellulose fibres CF. In this way, the three-dimensional body B of cellulose fibres CF is air-formed in a dry and controlled fibre forming process in which the cellulose fibres CF are air-formed onto the three-dimensional surface SSD of the of the three- dimensional shaping structure S by means of the flow of air A as carrying medium for the cellulose fibres CF. It should be understood that even if the three-dimensional body B of cellulose fibres CF is slightly compacted before the forming of the cellulose products 1 , such as compacting the three-dimensional body B for feeding or transportation purposes, the three-dimensional body B still comprises loose and separated cellulose fibres CF.

[0037] The three-dimensional surface SSD of the of the three-dimensional shaping structure S is defined as a non-planar surface having a three-dimensional shape for an efficient forming of the three-dimensional body B of cellulose fibres CF. The three-dimensional surface SSD of the three-dimensional shaping structure S has a surface configuration adapted to the configuration of the forming mould for an efficient positioning of the three-dimensional body B of cellulose fibres CF in the forming mould M without larger deformations. The three-dimensional surface SSD of the three-dimensional shaping structure S may have any suitable three-dimensional configuration, and the three- dimensional surface SSD may for example be arranged with elevated, undulating, rounded and / or step-like surface sections. Suitably, the three-dimensional surface SSD of the three-dimensional shaping structure S has a shape corresponding to or similar to a final shape of the cellulose product 1 formed in the forming mould M. In this way, the shape of the three-dimensional body B of cellulose fibres CF suitably has a shape corresponding to or similar to a final shape of the cellulose product 1 formed in the forming mould M.

[0038] With an air-formed three-dimensional body B of cellulose fibres CF is meant an essentially air-formed fibrous structure produced from cellulose fibres CF, where cellulose fibres CF are carried and formed to the three-dimensional body B of cellulose fibres CF by air as carrying medium. This is different from a normal papermaking process or a traditional wet-forming process, where water is used as carrying medium for the cellulose fibres when forming the paper or fibre structure. In the air-forming process, small amounts of water or other substances may if desired be added to the cellulose fibres in order to change the properties of the cellulose products, but air is still used as carrying medium in the forming process. The small amount of water has the advantage of enabling forming of hydrogen bonds between the fibres in the forming mould when subjected to pressure and temperature. The hydrogen bonds are an important factor for rigidity of the cellulose product.

[0039] The three-dimensional body B of cellulose fibres CF may have a composition where the fibres are of the same origin or alternatively contain a mix of two or more types of cellulose fibres, depending on the desired properties of the cellulose products 1. The cellulose fibres CF used in the three-dimensional body B of cellulose fibres CF are during the forming process of the cellulose products 1 strongly bonded to each other. The cellulose fibres CF may be mixed with other substances or compounds to a certain amount. With cellulose fibres is meant any type of cellulose fibres, such as natural cellulose fibres or manufactured cellulose fibres. The three-dimensional body B of cellulose fibres CF may specifically comprise at least 95% cellulose fibres, or more specifically at least 99% cellulose fibres. However, the three-dimensional body B of cellulose fibres CF may have other suitable configurations and cellulose fibre amounts.

[0040] As described above, the loose and separated cellulose fibres are arranged onto the three-dimensional surface SSD of the three-dimensional shaping structure S by means of the flow of air A for air-forming a three-dimensional body B of cellulose fibres CF. The three-dimensional surface SSD of the three-dimensional shaping structure S is in this way defining the three-dimensional shape of the three-dimensional body B of cellulose fibres CF. Suitably, the three-dimensional shaping structure S is arranged as a three-dimensional net structure or as a three-dimensional perforated structure that is made of a relatively stiff material for an efficient air-forming of the three- dimensional body B of cellulose fibres CF onto the three-dimensional surface SSD, and for efficient transport of the air-formed three-dimensional body B of cellulose fibres CF together with the three-dimensional shaping structure S from the fibre transporting unit T to the forming mould M. Suitable material configurations for the three- dimensional shaping structure S are for example three-dimensional steel structures, three-dimensional aluminium structures, three-dimensional plastic structures, or three-dimensional composite structures.

[0041] The three-dimensional surface SSD of the three-dimensional shaping structure S has a shape corresponding to a shape of a three-dimensional pressing surface SPSD of the forming mould M. When positioning the three-dimensional shaping structure S with the air-formed three-dimensional body B of cellulose fibres CF in the forming mould M, the cellulose product 1 is dry-formed into a three-dimensional compressed structure CSD in the pressing operation OP by pressing and heating the three- dimensional shaping structure S with the three-dimensional body B of cellulose fibres CF in the forming mould M with the forming pressure Pp and the forming temperature TF.

[0042] The forming mould M is thus used for dry-forming the cellulose products 1 into a three- dimensional compressed structure CSD by pressing and heating the three-dimensional body B of cellulose fibres CF and the three-dimensional shaping structure S in the forming mould M with a forming pressure Pp in the range of 1-600 MPa, preferably in the range of 1-100 MPa, more preferably in the range of 4-20 MPa, and a forming temperature Tp in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C. The forming pressure Pp may selectively be higher in specific parts or areas of the forming mould M. This higher forming pressure Pp may be used for forming sections of the cellulose product 1 having a higher stiffness.

[0043] Figures 1a-f schematically show an embodiment of a product forming unit II in which cellulose products 1 are dry-formed from cellulose fibres CF. The product forming unit II comprises a fibre transporting unit T and a forming mould M. The product forming unit II further comprises a support structure 11 arranged in connection to the fibre transporting unit T. The fibre transporting unit T is used for feeding loose and separated cellulose fibres CF into a flow of air A, and for transporting the cellulose fibres CF to a three-dimensional shaping structure S by means of the flow of air A as carrying medium for the cellulose fibres CF. The support structure 11 is used for holding the three-dimensional shaping structure S for forming a three-dimensional body B of cellulose fibres CF onto the three-dimensional shaping structure S from the cellulose fibres CF transported by the flow of air A to the three-dimensional shaping structure S.

[0044] The three-dimensional shaping structure S is illustrated in figure 2a, and the three- dimensional shaping structure S comprises a three-dimensional surface SSD. The three-dimensional body B of cellulose fibres CF is formed onto the three-dimensional surface SSD from the cellulose fibres CF transported by the flow of air A to the three- dimensional shaping structure S, as will be further described below. The three- dimensional shaping structure S may have any suitable three-dimensional shape and configuration, such as for example shapes with male and / or female configurations.

[0045] In figure 2a, a three-dimensional shaping structure S with a male configuration is schematically illustrated, and in figure 2b, an alternative embodiment of a three- dimensional shaping structure S with a female configuration is schematically illustrated.

[0046] In the embodiment shown in figures 1 a-f , the fibre transporting unit T comprises a flow channel 8 in which a flow of air A is introduced, for example by a suitable fan unit or other air flow establishing device of the fibre transporting unit T. The three- dimensional shaping structure S is arranged in connection to the flow channel 8 upon forming of the three-dimensional body B of cellulose fibres CF to enable the distribution of cellulose fibres CF onto the three-dimensional surface SSD. The fibre transporting unit T comprises a fibre outlet TFO, and the fibre outlet TFO is suitably arranged in connection to the flow channel 8. The fibre outlet TFO may be configured as a hood H or similar arrangement, for an efficient distribution of cellulose fibres CF onto the three-dimensional shaping structure S. Loose and separated cellulose fibres CF are introduced into the flow of air A for forming a mix of air and cellulose fibres CF that are transported by means of the flow of air A in the flow channel 8. The loose and separated cellulose fibres CF are in this way fed in the fibre transporting unit T by means of a flow of air A to the fibre outlet TFO of the fibre transporting unit T.

[0047] In other non-illustrated embodiments, two or more flow channels 8 may be arranged in connection to the support structure 11 , for feeding different types of cellulose fibres CF to the three-dimensional shaping structure S. In this way, air-forming of the three- dimensional body B of cellulose fibres CF with layers of different cellulose fibres CF is enabled. In some embodiments, a non-illustrated mill unit may be arranged in connection to the flow channel 8. The mill unit may be used for both separating cellulose raw material into loose and separated cellulose fibres CF and establishing the flow of air A in the flow channel 8. A mix of cellulose fibres CF into the flow of air A may be established directly by the mill unit.

[0048] As indicated in figures 1a-f, the fibre transporting unit T is feeding the loose and separated cellulose fibres CF in the flow channel 8 to the three-dimensional surface SSD of the three-dimensional shaping structure S by means of the flow of air A.

[0049] As shown in for example figure 2a, the three-dimensional shaping structure S comprises an outer surface So and an inner surface Si. The inner surface Si is arranged opposite the outer surface So. A plurality of suction openings 7 are connecting the outer surface So and the inner surface Si. In this embodiment, the three-dimensional surface SSD is arranged as the outer surface So of the three- dimensional shaping structure S. The three-dimensional surface SSD of the three- dimensional shaping structure S is configured for receiving the loose and separated cellulose fibres CF by means of the flow of air A for forming the three-dimensional body B of cellulose fibres CF upon application of a negative pressure PN via the suction openings 7 for distributing the cellulose fibres CF onto the three-dimensional surface SSD, as schematically illustrated in figure 1c. The three-dimensional shaping structure S may suitably be arranged as a three-dimensional net structure or as a solid perforated structure, as described above. The suction openings 7 may have any suitable shape, size and configuration. The shape and / or size of the suction openings 7 may vary between different parts of the three-dimensional shaping structure S, as well as the number of suction openings 7 arranged in the three-dimensional shaping structure S.

[0050] In other non-illustrated embodiments, the three-dimensional shaping structure S are only partly arranged with suction openings 7 for steering and controlling the flow of cellulose fibres CF.

[0051] In further non-illustrated embodiments, the three-dimensional shaping structure S may be arranged without the suction openings, and the cellulose fibres CF are deposited onto the three-dimensional surface SSD without the need for applying a negative pressure through the three-dimensional shaping structure S. In this way, the cellulose fibres CF are instead shot or sprayed onto the three-dimensional surface SSD by a flow of air A as carrying medium for the cellulose fibres CF.

[0052] In further non-illustrated embodiments, the three-dimensional surface SSD is instead arranged as the inner surface Si of the three-dimensional shaping structure S. Alternatively, the three-dimensional surface SSD may be arranged fully or partly as the outer surface So and the inner surface Si of the three-dimensional shaping structure S, or the three-dimensional surface SSD may be arranged as one or more parts of the outer surface So and / or the inner surface Si of the three-dimensional shaping structure S.

[0053] The forming of the three-dimensional body B of cellulose fibres CF is sequentially illustrated in figures 1a-f. In figure 1a, a provided three-dimensional shaping structure S is transported to the fibre transporting unit T, as indicated with the arrow. Thereafter, the provided three-dimensional shaping structure S is arranged on the support structure 11 in connection to the to the fibre outlet TFO of the fibre transporting unit T, into a position in which cellulose fibres CF can be deposited onto the three- dimensional shaping structure S, as shown in figure 1b. In the illustrated embodiment, the support structure 11 is configured as a stationary support structure, and the three- dimensional shaping structure S is transported to the position in figure 1b with any suitable transportation means. In this position, the three-dimensional shaping structure S is empty and ready for receiving cellulose fibres CF from the fibre transporting unit T. The fibre transporting unit T is suitably movably arranged, and the hood H with the fibre outlet TFO may in this way be positioned over the three- dimensional shaping structure S, as understood from the figure.

[0054] When the three-dimensional shaping structure S is arranged in connection to the fibre outlet TFO of the fibre transporting unit T, as shown in figure 1 b, the loose and separated cellulose fibres CF are deposited onto the three-dimensional surface SSD of the three-dimensional shaping structure S by means of the flow of air A for airforming a three-dimensional body B of cellulose fibres CF.

[0055] In the position shown in figure 1b, the three-dimensional shaping structure S is arranged in direct connection to the fibre outlet TFO, and the loose and separated cellulose fibres CF transported in the fibre transporting unit T are deposited onto the three-dimensional surface SSD. The loose and separated cellulose fibres CF are fed from the fibre outlet TFO to the three-dimensional shaping structure S by means of the flow of air A as carrying medium for the cellulose fibres CF, and the three-dimensional body B of cellulose fibres CF is built up on the three-dimensional surface SSD. The three-dimensional surface SSD of the three-dimensional shaping structure S is suitably receiving the loose and separated cellulose fibres CF by means of the flow of air A for forming the three-dimensional body B of cellulose fibres CF by applying a negative pressure PN via the suction openings 7 for distributing the cellulose fibres CF onto the three-dimensional surface SSD.

[0056] The three-dimensional body B of cellulose fibres CF is air-formed in a dry and controlled fibre forming process in which the cellulose fibres CF are deposited onto the three-dimensional surface SSD of the three-dimensional shaping structure S by means of the flow of air A as carrying medium for the cellulose fibres CF when the three-dimensional shaping structure S is arranged in connection to the fibre outlet TFO. When a suitable amount of cellulose fibres CF are formed onto the three-dimensional surface SSD, as shown in figure 1c, the three-dimensional body B of cellulose fibres CF is formed, and thereafter the three-dimensional shaping structure S with the formed three-dimensional body B of cellulose fibres CF can be further transported to the forming mould M, as indicated with the arrow in figure 1c.

[0057] In figure 1d, the three-dimensional shaping structure S with the air-formed three- dimensional body B of cellulose fibres CF is positioned in the forming mould M. The forming mould M is configured for dry-forming the cellulose product 1 into a three- dimensional compressed structure CSD in a pressing operation OP, by pressing and heating the three-dimensional shaping structure S with the three-dimensional body B of cellulose fibres CF in the forming mould M with a forming pressure Pp and a forming temperature TF.

[0058] In the embodiment shown in figures 1 a-f , the forming mould M comprises a first mould part 3a and a corresponding second mould part 3b that are cooperating for forming the cellulose products 1 from the three-dimensional bodies B of cellulose fibres CF. The first mould part 3a and the second mould part 3b are movably arranged relative to each other, and the first mould part 3a and the second mould part 3b are configured for moving relative to each other in a pressing direction Dp. The second mould part 3b is stationary and the first mould part 3a is movably arranged in relation to the second mould part 3b in the pressing direction DP, during the pressing operation OP. As indicated with the double arrow in figure 1a, the first mould part 3a is configured to move both towards the second mould part 3b and away from the second mould part 3b in linear movements along an axis extending in the pressing direction Dp.

[0059] It should be understood that for all embodiments according to the disclosure, the expression moving in the pressing direction DP includes a movement in the pressing direction DP, and the movement may take place in opposite directions. The expression may further include both linear and non-linear movements of a mould part, where the result of the movement during forming is a repositioning of the mould part in the pressing direction Dp.

[0060] The three-dimensional surface SSD of the three-dimensional shaping structure S is in the embodiment shown in figures 1a-f used for pressing the three-dimensional body B of cellulose fibres CF. The three-dimensional surface SSD of the three-dimensional shaping structure S has a shape corresponding to a shape of a three-dimensional pressing surface SPSD of the forming mould M. In this embodiment, the first mould part 3a comprises the three-dimensional pressing surface SPSD. Thus, the three- dimensional surface SSD of the three-dimensional shaping structure S has a shape corresponding to the shape of a three-dimensional pressing surface SPSD of the first mould part 3a. As described above, the three-dimensional surface SSD is an outer surface So of the three-dimensional shaping structure S, and the three-dimensional surface SSD is arranged as a pressing surface in connection to the second mould part 3b for an efficient forming of the cellulose product 1. The three-dimensional pressing surface SPSD of the first mould part 3a and the three-dimensional surface SSD of the three-dimensional shaping structure S are configured as cooperating pressing surfaces during the pressing operation OP.

[0061] The three-dimensional pressing surface SPSD of the first mould part 3a is arranged as an outer surface that is arranged to press the three-dimensional shaping structure S and the formed three-dimensional body B of cellulose fibres CF during the pressing operation OP, when the three-dimensional shaping structure S with the formed three- dimensional body B of cellulose fibres CF is arranged between the first mould part 3a and the second mould part 3b. By arranging the three-dimensional surface SSD of the three-dimensional shaping structure S and the three-dimensional pressing surface SPSD of the first mould part 3a with corresponding shapes, an efficient cellulose product forming process is achieved. This is for example desired if deep drawn products are formed.

[0062] With the expression corresponding shape is meant that the three-dimensional surface SSD of the three-dimensional shaping structure S and the three-dimensional pressing surface SPSD of the forming mould M, such as the surface in the first mould part 3a, have three-dimensional shapes that are similar in configuration, resulting in the forming of a three-dimensional body B of cellulose fibres CF that fits in the forming mould M without large deformations. It should be understood that the three- dimensional surface SSD of the three-dimensional shaping structure S and at least one three-dimensional pressing surface SPSD of the forming mould M may or may not be identical, but at least arranged with corresponding three-dimensional shapes for an efficient positioning and pressing operation OP of the three-dimensional body B of cellulose fibres CF in the forming mould M.

[0063] In the embodiment shown in figures 1a-f, the second mould part 3b comprises a receiving surface 9 arranged for holding the three-dimensional shaping structure S with the formed three-dimensional body B of cellulose fibres CF. As shown in figure 1 d, the three-dimensional shaping structure S with the formed three-dimensional body B of cellulose fibres CF is positioned onto the receiving surface 9 of the second mould part 3b, and in this position, the forming mould M is ready for initiating the pressing operation OP.

[0064] In other non-illustrated embodiments, the second mould part 3b instead comprises the three-dimensional pressing surface SPSD, and the first mould part 3a may then comprise a receiving surface 9 arranged for holding the three-dimensional shaping structure S with the formed three-dimensional body B of cellulose fibres CF.

[0065] The forming mould M is configured for dry-forming the cellulose product 1 into a three- dimensional compressed structure CSD in a pressing operation OP from the three- dimensional body B of cellulose fibres CF, by pressing and heating the three- dimensional shaping structure S with the three-dimensional body B of cellulose fibres CF with a forming pressure Pp and a forming temperature Tp. The forming mould M is applying the forming pressure Pp by pressing the three-dimensional shaping structure S with the air-formed three-dimensional body B of cellulose fibres CF between the first mould part 3a and the second mould part 3b, as shown in figure 1e. The forming mould M is further applying the forming temperature TF onto the three-dimensional shaping structure S with the air-formed three-dimensional body B of cellulose fibres CF.

[0066] When the three-dimensional body B of cellulose fibres CF is formed with a shape corresponding to the shape of the first mould part 3a, as shown in figures 1 a-f, the dry-forming operation in the forming mould M can be made with reduced risks of weak material sections and / or cracks in the final cellulose product 1 , since the three- dimensional body B of cellulose fibres CF will not be stretched out a major extent during the pressing operation OP in the forming mould M.

[0067] With the expression pressing operation OP is meant the operation of the mould parts for forming a cellulose product 1 from the three-dimensional body B of cellulose fibres CF. In the embodiment shown in figures 1 a-f, the pressing operation OP starts when the first mould part 3a is moved from a stationary position. In this position, the first mould part 3a and the second mould part 3b are arranged at a distance from each other and the three-dimensional shaping structure S with the three-dimensional body B of cellulose fibres CF can be fed into the forming mould M in a forming position between the first mould part 3a and the second mould part 3b, as illustrated in figures 1c-d.

[0068] When the cellulose product is formed in the forming mould M, the first mould part 3a is moved away from the second mould part 3b back to the stationary position, as understood from figures 1e-f. When the first mould part 3a has reached the stationary position again, the pressing operation OP is completed. The pressing operation OP is thus defined as a pressing cycle during which the three-dimensional shaping structure S with the three-dimensional body B of cellulose fibres CF is exerted to the forming pressure PF, and the duration of the pressing operation OP is suitably calculated from the start of the movement of the first mould part 3a from the stationary position until the first mould part 3a has reached the stationary position again.

[0069] The forming mould M is configured for dry-forming the cellulose product 1 from the three-dimensional body B of cellulose fibres CF in the pressing operation OP, and the three-dimensional shaping structure S is supporting the three-dimensional body B of cellulose fibres CF during the pressing operation OP. The forming mould M is in the pressing operation OP dry-forming the cellulose product 1 into a three-dimensional compressed structure CSD by pressing and heating the three-dimensional body B of cellulose fibres CF in the forming mould M with a forming pressure PF in the range of 1-600 MPa, preferably in the range of 1-100 MPa, more preferably in the range of 4- 20 MPa, and a forming temperature TF in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C. In this way, the cellulose fibres CF in the three-dimensional body B of cellulose fibres CF are integrated into the three-dimensional compressed structure CSD.

[0070] The forming pressure PF may selectively be higher in specific parts or areas of the forming mould M. This higher forming pressure Pp may be used for forming sections of the cellulose product 1 having a higher stiffness.

[0071] The three-dimensional body B of cellulose fibres CF may be compacted before dryforming the cellulose product 1 in the forming mould M. The compacting operation is compressing the fibre structure of the three-dimensional body B of cellulose fibres CF into a more dense structure, without influencing the general three-dimensional shape.

[0072] The forming mould M may further comprise a heating unit. The heating unit is configured for applying the forming temperature TF onto the three-dimensional body B of cellulose fibres CF during the forming operation in the forming mould M. The heating unit may have any suitable configuration. The heating unit may be integrated in or cast into the first mould part 3a and / or second mould part 3b, and suitable heating devices are e.g. electrical heaters, such as resistor elements, or fluid heaters. Other suitable heat sources may also be used.

[0073] The forming pressure PF may be applied to the three-dimensional body B of cellulose fibres CF in only one pressing step during the pressing operation OP. Suitably, the cellulose product 1 is dry-formed into the three-dimensional compressed structure CSD in a single pressing operation by pressing and heating the three-dimensional body B of cellulose fibres CF in the forming mould M with the forming pressure PF and the forming temperature TF. In this way, the forming pressure PF and the forming temperature TF are applied onto the three-dimensional body B of cellulose fibres CF during a single pressing operation upon forming of the cellulose product 1 in the forming mould M. With a single pressing operation is meant that the cellulose product 1 is formed from the three-dimensional body B of cellulose fibres CF in one single pressing step in the forming mould M. In the single pressing operation, the first mould part 3a and the second mould part 3b are interacting with each other for establishing the forming pressure PF and the forming temperature TF during a single operational engagement step. Thus, in the single pressing operation, the forming pressure PF and the forming temperature TF are not applied to the three-dimensional body B of cellulose fibres CF in two or more repeated pressing steps.

[0074] Alternatively, the forming pressure PF may be applied in two or more repeated pressing steps during the pressing operation OP, and in this way, the mould parts are repeatedly exerting the forming pressure PF onto the three-dimensional body B of cellulose fibres CF.

[0075] After the pressing operation OP in the forming mould M, the formed three-dimensional compressed structure CSD and the three-dimensional shaping structure S are removed from the forming mould M, and the three-dimensional compressed structure CSD is separated from the three-dimensional shaping structure S, as illustrated with arrows in figure 1f.

[0076] It should be understood that the forming mould M may have other configurations. In alternative non-illustrated embodiments, the first mould part 3a may be stationary and the second mould part 3b movably arranged in relation to the first mould part 3a during the pressing operation OP, or both the first mould part 3a and the second mould part 3b are movably arranged towards and away from each other.

[0077] The forming mould M may have a single-cavity configuration with one first mould part 3a and one second mould part 3b cooperating with each other for dry-forming the cellulose products 1 , as shown in figures 1a-f.

[0078] Alternatively, the forming mould M may have a multi-cavity configuration, where instead two or more first mould parts 3a are cooperating with two or more corresponding second mould parts 3b. In this way, two or more cellulose products 1 can be produced in one pressing operation OP. A single-cavity configuration forming mould M thus comprises only one first mould part 3a and a cooperating second mould part 3b. A multi-cavity configuration forming mould M comprises two or more cooperating first mould parts 3a and second mould parts 3b. It should be understood that even if the forming mould M is described in connection to a single-cavity configuration forming mould, the disclosure is equally applicable on multi-cavity configuration forming moulds.

[0079] Figures 3a-h schematically show another embodiment of a product forming unit II in which cellulose products 1 are dry-formed from cellulose fibres CF. The product forming unit II comprises a fibre transporting unit T and a forming mould M. The product forming unit II further comprises a movable support structure 11 arranged in connection to the fibre transporting unit T. The fibre transporting unit T is used for feeding loose and separated cellulose fibres CF into a flow of air A, and for transporting the cellulose fibres CF to a three-dimensional shaping structure S by means of the flow of air A as carrying medium for the cellulose fibres CF. The movable support structure 11 is used for holding one or more three-dimensional shaping structures S, for forming a three-dimensional body B of cellulose fibres CF onto each of the one or more three-dimensional shaping structures S from the cellulose fibres CF transported by the flow of air A.

[0080] The three-dimensional shaping structure S may have the same configuration as described in the embodiment above in connection to figures 1a-f, where the three- dimensional shaping structure S comprises a three-dimensional surface SSD. The three-dimensional body B of cellulose fibres CF is formed onto the three-dimensional surface SSD from the cellulose fibres CF transported by the flow of air A to three- dimensional shaping structure S, as will be further described below. The three- dimensional shaping structure S may have any suitable three-dimensional shape and configuration, such as for example shapes with male and / or female configurations.

[0081] In the embodiment shown in figures 3a-h, the fibre transporting unit T comprises a flow channel 8 in which a flow of air A is introduced, for example by a suitable fan unit or other air flow establishing device of the fibre transporting unit T. The three- dimensional shaping structure S is arranged in connection to the flow channel 8 upon forming of the three-dimensional body B of cellulose fibres CF to enable the distribution of cellulose fibres CF onto the three-dimensional surface SSD. The fibre transporting unit T comprises a fibre outlet TFO, and the fibre outlet TFO is suitably arranged in connection to the flow channel 8. The fibre outlet TFO may be configured as a hood H or similar arrangement, for an efficient distribution of cellulose fibres CF onto the three-dimensional shaping structure S. Loose and separated cellulose fibres CF are introduced into the flow of air A for forming a mix of air and cellulose fibres CF that are transported by means of the flow of air A in the flow channel 8. The loose and separated cellulose fibres CF are in this way fed in the fibre transporting unit T by means of a flow of air A to the fibre outlet TFO of the fibre transporting unit T.

[0082] In other non-illustrated embodiments, two or more flow channels 8 may be arranged in connection to the support structure 11 , for feeding different types of cellulose fibres CF to the three-dimensional shaping structure S. In this way, air-forming of the three- dimensional body B of cellulose fibres CF with layers of different cellulose fibres CF is enabled.

[0083] In some embodiments, a non-illustrated mill unit may be arranged in connection to the flow channel 8. The mill unit may be used for both separating cellulose raw material into loose and separated cellulose fibres CF and establishing the flow of air A in the flow channel 8. A mix of cellulose fibres CF into the flow of air A may be established directly by the mill unit.

[0084] As indicated in figures 3a-h, the fibre transporting unit T is feeding the loose and separated cellulose fibres CF in the flow channel 8 to the three-dimensional surface SSD of the three-dimensional shaping structure S by means of the flow of air A.

[0085] The three-dimensional shaping structure S comprises an outer surface So and an inner surface Si. The inner surface Si is arranged opposite the outer surface So. A plurality of suction openings 7 are connecting the outer surface So and the inner surface Si. In this embodiment, the three-dimensional surface SSD is arranged as the outer surface So of the three-dimensional shaping structure S. The three-dimensional surface SSD of the three-dimensional shaping structure S is configured for receiving the loose and separated cellulose fibres CF by means of the flow of air A for forming the three-dimensional body B of cellulose fibres CF upon application of a negative pressure PN via the suction openings 7 for distributing the cellulose fibres CF onto the three-dimensional surface SSD, as schematically illustrated in figure 3d. The three- dimensional shaping structure S may suitably be arranged as a three-dimensional net structure or as a solid perforated structure, as described above. The suction openings 7 may have any suitable shape, size and configuration. The shape and / or size of the suction openings 7 may vary between different parts of the three-dimensional shaping structure S, as well as the number of suction openings 7 arranged in the three- dimensional shaping structure S.

[0086] In other non-illustrated embodiments, the three-dimensional shaping structure S are only partly arranged with suction openings 7 for steering and controlling the flow of cellulose fibres CF.

[0087] In further non-illustrated embodiments, the three-dimensional shaping structure S may be arranged without the suction openings, and the cellulose fibres CF are deposited onto the three-dimensional surface SSD without the need for applying a negative pressure through the three-dimensional shaping structure S. In this way, the cellulose fibres CF are instead shot or sprayed onto the three-dimensional surface SSD by a flow of air A as carrying medium for the cellulose fibres CF.

[0088] In further non-illustrated embodiments, the three-dimensional surface SSD is instead arranged as the inner surface Si of the three-dimensional shaping structure S. Alternatively, the three-dimensional surface SSD may be arranged fully or partly as the outer surface So and the inner surface Si of the three-dimensional shaping structure S, or the three-dimensional surface SSD may be arranged as one or more parts of the outer surface So and / or the inner surface Si of the three-dimensional shaping structure S.

[0089] In the embodiment illustrated in figures 3a-h, the support structure 11 is configured as a movable support structure arranged as an endless circulating support structure having a belt-like configuration. The one or more three-dimensional shaping structures S are transported to the fibre outlet TFO, by means of the movable support structure 11 , and in this position, the three-dimensional shaping structure S is empty and ready for receiving cellulose fibres CF from the fibre transporting unit T.

[0090] The forming of the three-dimensional body B of cellulose fibres CF is sequentially illustrated in the figures. In figures 3a-c, a provided first three-dimensional shaping structure Si is arranged on the movable support structure 11 and transported to the fibre transporting unit T, as indicated with the arrow in figure 3b. When the provided first three-dimensional shaping structure Si is transported by the movable support structure 11 and positioned in connection to the to the fibre outlet TFO of the fibre transporting unit T, as shown in figure 3c, the movable support structure 11 is suitably stopped and the cellulose fibres CF can be deposited onto the first three-dimensional shaping structure Si. In this position, the three-dimensional shaping structure S is empty and ready for receiving cellulose fibres CF from the fibre transporting unit T. The fibre transporting unit T is suitably movably arranged, and the hood H with the fibre outlet TFO may in this way be positioned over the three-dimensional shaping structure S, as understood from figures 3c-d.

[0091] When the first three-dimensional shaping structure Si is positioned in connection to the fibre outlet TFO of the fibre transporting unit T, one or more further three- dimensional shaping structures may be arranged on the movable support structure 11 , such as a second three-dimensional shaping structure S2 shown in figure 3c.

[0092] When the first three-dimensional shaping structure Si is arranged in connection to the fibre outlet TFO of the fibre transporting unit T, as shown in figure 3d, the loose and separated cellulose fibres CF are deposited onto the three-dimensional surface SSD of the three-dimensional shaping structure S by means of the flow of air A for airforming a three-dimensional body B of cellulose fibres CF.

[0093] In the position shown in figure 3d, the first three-dimensional shaping structure Si is arranged in direct connection to the fibre outlet TFO, and the loose and separated cellulose fibres CF transported in the fibre transporting unit T are deposited onto the three-dimensional surface SSD. The loose and separated cellulose fibres CF are fed from the fibre outlet TFO to the first three-dimensional shaping structure Si by means of the flow of air A as carrying medium for the cellulose fibres CF, and the three- dimensional body B of cellulose fibres CF is built up on the three-dimensional surface SSD. The three-dimensional surface SSD of the first three-dimensional shaping structure Si is suitably receiving the loose and separated cellulose fibres CF by means of the flow of air A for forming the three-dimensional body B of cellulose fibres CF by applying a negative pressure PN via the suction openings 7 for distributing the cellulose fibres CF onto the three-dimensional surface SSD.

[0094] The three-dimensional body B of cellulose fibres CF is air-formed in a dry and controlled fibre forming process in which the cellulose fibres CF are deposited onto the three-dimensional surface SSD of the first three-dimensional shaping structure Si by means of the flow of air A as carrying medium for the cellulose fibres CF when the first three-dimensional shaping structure Si is arranged in connection to the fibre outlet TFO. When a suitable amount of cellulose fibres CF are formed onto the three- dimensional surface SSD, as shown in figure 3e, the three-dimensional body B of cellulose fibres CF is formed, and thereafter the first three-dimensional shaping structure Si with the formed three-dimensional body B of cellulose fibres CF can be further transported to the forming mould M, as indicated with the arrow in figure 3e.

[0095] In figure 3f, the first three-dimensional shaping structure Si with the air-formed three- dimensional body B of cellulose fibres CF is positioned in the forming mould M. The forming mould M is configured for dry-forming the cellulose product 1 into a three- dimensional compressed structure CSD in a pressing operation OP, by pressing and heating the three-dimensional shaping structure S with the three-dimensional body B of cellulose fibres CF in the forming mould M with a forming pressure Pp and a forming temperature Tp. As understood from figure 3f, when the first three-dimensional shaping structure Si with the air-formed three-dimensional body B of cellulose fibres CF is positioned in the forming mould M, the second three-dimensional shaping structure S2 is transported to the fibre transporting unit T and a third three-dimensional shaping structure S3 is arranged on the movable support structure 11 .

[0096] In the embodiment shown in figures 3g-h, the forming mould M comprises a first mould part 3a and a corresponding second mould part 3b that are cooperating for forming the cellulose products 1 from the three-dimensional bodies B of cellulose fibres CF. The forming mould may have the configurations and functions described above in connection to figures 1a-f. As indicated with the double arrow in figure 3a, the first mould part 3a is configured to move both towards the second mould part 3b and away from the second mould part 3b in linear movements along an axis extending in the pressing direction Dp.

[0097] The three-dimensional surface SSD of the three-dimensional shaping structure S is in the embodiment shown in figures 3a-h used for pressing the three-dimensional body B of cellulose fibres CF. The three-dimensional surface SSD of the three-dimensional shaping structure S has a shape corresponding to a shape of a three-dimensional pressing surface SPSD of the forming mould M. In this embodiment, the first mould part 3a comprises the three-dimensional pressing surface SPSD. Thus, the three- dimensional surface SSD of the three-dimensional shaping structure S has a shape corresponding to the shape of a three-dimensional pressing surface SPSD of the first mould part 3a. As described above, the three-dimensional surface SSD is an outer surface So of the three-dimensional shaping structure S, and the three-dimensional surface SSD is arranged as a pressing surface in connection to the second mould part 3b for an efficient forming of the cellulose product 1. The three-dimensional pressing surface SPSD of the first mould part 3a and the three-dimensional surface SSD of the three-dimensional shaping structure S are configured as cooperating pressing surfaces during the pressing operation OP.

[0098] The three-dimensional pressing surface SPSD of the first mould part 3a is arranged as an outer surface that is arranged to press the three-dimensional shaping structure S and the formed three-dimensional body B of cellulose fibres CF during the pressing operation OP, when the three-dimensional shaping structure S with the formed three- dimensional body B of cellulose fibres CF is arranged between the first mould part 3a and the second mould part 3b. By arranging the three-dimensional surface SSD of the three-dimensional shaping structure S and the three-dimensional pressing surface SPSD of the first mould part 3a with corresponding shapes, as described above, an efficient cellulose product forming process is achieved. This is for example desired if deep drawn products are formed.

[0099] In the embodiment shown in figures 3a-h, the second mould part 3b comprises a receiving surface 9 arranged for holding the three-dimensional shaping structure S with the formed three-dimensional body B of cellulose fibres CF. As shown in figure 3f, the first three-dimensional shaping structure Si with the formed three-dimensional body B of cellulose fibres CF is positioned onto the receiving surface 9 of the second mould part 3b, and in this position, the forming mould M is ready for initiating the pressing operation OP.

[0100] The forming mould M is configured for dry-forming the cellulose product 1 into a three- dimensional compressed structure CSD in a pressing operation OP from the three- dimensional body B of cellulose fibres CF, by pressing and heating the three- dimensional shaping structure S with the three-dimensional body B of cellulose fibres CF with a forming pressure Pp and a forming temperature Tp. The forming mould M is applying the forming pressure Pp by pressing the first three-dimensional shaping structure Si with the air-formed three-dimensional body B of cellulose fibres CF between the first mould part 3a and the second mould part 3b, as shown in figure 3g. The forming mould M is further applying the forming temperature Tp onto the three- dimensional shaping structure S with the air-formed three-dimensional body B of cellulose fibres CF. As shown in figure 3g, a further three-dimensional body B of cellulose fibres CF may be formed onto the second three-dimensional shaping structure S2 during the pressing operation OP in the forming mould M.

[0101] When the three-dimensional body B of cellulose fibres CF is formed with a shape corresponding to the shape of the first mould part 3a, as shown in figures 3a-h, the dry-forming operation in the forming mould M can be made with reduced risks of weak material sections and / or cracks in the final cellulose product 1 , since the three- dimensional body B of cellulose fibres CF will not be stretched out a major extent during the pressing operation OP in the forming mould M.

[0102] With the expression pressing operation OP is meant the operation of the mould parts for forming a cellulose product 1 from the three-dimensional body B of cellulose fibres CF. In the embodiment shown in figures 3a-h, the pressing operation OP starts when the first mould part 3a is moved from a stationary position. In this position, the first mould part 3a and the second mould part 3b are arranged at a distance from each other and the three-dimensional shaping structure S with the three-dimensional body B of cellulose fibres CF can be fed into the forming mould M in a forming position between the first mould part 3a and the second mould part 3b, as illustrated in figures 3e-f.

[0103] When the cellulose product is formed in the forming mould M, the first mould part 3a is moved away from the second mould part 3b back to the stationary position, as understood from figures 3g-h. When the first mould part 3a has reached the stationary position again, the pressing operation OP is completed. The pressing operation OP is thus defined as a pressing cycle during which the three-dimensional shaping structure S with the three-dimensional body B of cellulose fibres CF is exerted to the forming pressure PF, and the duration of the pressing operation OP is suitably calculated from the start of the movement of the first mould part 3a from the stationary position until the first mould part 3a has reached the stationary position again.

[0104] The forming mould M is configured for dry-forming the cellulose product 1 from the three-dimensional body B of cellulose fibres CF in the pressing operation OP, and the three-dimensional shaping structure S is supporting the three-dimensional body B of cellulose fibres CF during the pressing operation OP. The forming mould M is in the pressing operation OP dry-forming the cellulose product 1 into a three-dimensional compressed structure CSD by pressing and heating the three-dimensional body B of cellulose fibres CF in the forming mould M with a forming pressure PF in the range of 1-600 MPa, preferably in the range of 1-100 MPa, more preferably in the range of 4- 20 MPa, and a forming temperature TF in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C. In this way, the cellulose fibres CF in the three-dimensional body B of cellulose fibres CF are integrated into the three-dimensional compressed structure CSD.

[0105] The forming pressure PF may selectively be higher in specific parts or areas of the forming mould M. This higher forming pressure Pp may be used for forming sections of the cellulose product 1 having a higher stiffness.

[0106] The three-dimensional body B of cellulose fibres CF may be compacted before dryforming the cellulose product 1 in the forming mould M. The compacting operation is compressing the fibre structure of the three-dimensional body B of cellulose fibres CF into a more dense structure, without influencing the general three-dimensional shape.

[0107] The forming mould M may further comprise a heating unit, as described above in connection to figures 1a-h.

[0108] The forming pressure PF may be applied to the three-dimensional body B of cellulose fibres CF in only one pressing step during the pressing operation OP. Suitably, the cellulose product 1 is dry-formed into the three-dimensional compressed structure CSD in a single pressing operation by pressing and heating the three-dimensional body B of cellulose fibres CF in the forming mould M with the forming pressure PF and the forming temperature TF. In this way, the forming pressure PF and the forming temperature TF are applied onto the three-dimensional body B of cellulose fibres CF during a single pressing operation upon forming of the cellulose product 1 in the forming mould M. With a single pressing operation is meant that the cellulose product 1 is formed from the three-dimensional body B of cellulose fibres CF in one single pressing step in the forming mould M. In the single pressing operation, the first mould part 3a and the second mould part 3b are interacting with each other for establishing the forming pressure PF and the forming temperature TF during a single operational engagement step. Thus, in the single pressing operation, the forming pressure PF and the forming temperature TF are not applied to the three-dimensional body B of cellulose fibres CF in two or more repeated pressing steps. Alternatively, the forming pressure PF may be applied in two or more repeated pressing steps during the pressing operation OP, and in this way, the mould parts are repeatedly exerting the forming pressure PF onto the three-dimensional body B of cellulose fibres CF.

[0109] After the pressing operation OP in the forming mould M, the formed three-dimensional compressed structure CSD and the first three-dimensional shaping structure Si are removed from the forming mould M, and the three-dimensional compressed structure CSD is separated from the first three-dimensional shaping structure Si , as illustrated with arrows in figure 3h. Thereafter, the pressing operation OP may be repeated and the second three-dimensional shaping structure S2 with the formed three-dimensional body B of cellulose fibres CF may be positioned onto the receiving surface 9 of the second mould part 3b. In this position, the forming mould M is ready for initiating a further pressing operation OP.

[0110] It will be appreciated that the above description is merely exemplary in nature and is not intended to limit the present disclosure, its application or uses. While specific examples have been described in the specification and illustrated in the drawings, it will be understood by those of ordinary skill in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the present disclosure as defined in the claims. Furthermore, modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from the essential scope thereof. Therefore, it is intended that the present disclosure not be limited to the particular examples illustrated by the drawings and described in the specification as the best mode presently contemplated for carrying out the teachings of the present disclosure, but that the scope of the present disclosure will include any embodiments falling within the foregoing description and the appended claims. Reference signs mentioned in the claims should not be seen as limiting the extent of the matter protected by the claims, and their sole function is to make claims easier to understand. REFERENCE SIGNS

[0111] 1 : Cellulose product

[0112] 3a: First mould part

[0113] 3b: Second mould part

[0114] 7: Suction opening

[0115] 8: Flow channel

[0116] 9: Receiving surface

[0117] 11 : Support structure

[0118] A: Air

[0119] B: Three-dimensional body

[0120] CF: Cellulose fibres

[0121] CSD: Three-dimensional compressed structure

[0122] H: Hood

[0123] M: Forming mould

[0124] OP: Pressing operation

[0125] PF: Forming pressure

[0126] PN: Negative pressure

[0127] S: Three-dimensional shaping structure

[0128] SSD: Three-dimensional surface

[0129] Si: Inner surface

[0130] So: Outer surface

[0131] SPSD: Three-dimensional pressing surface

[0132] T: Fibre transporting unit

[0133] Tp: Forming temperature

[0134] Tpo: Fibre outlet

[0135] II: Product forming unit

Claims

CLAIMS1 . A method for dry-forming a three-dimensional cellulose product (1) from cellulose fibres (CF) in a product forming unit (II), wherein the product forming unit (II) comprises a fibre transporting unit (T) and a forming mould (M), wherein the method comprises the steps: providing loose and separated cellulose fibres (CF) to the fibre transporting unit (T), and feeding the loose and separated cellulose fibres (CF) in the fibre transporting unit (T) by means of a flow of air (A); feeding of the loose and separated cellulose fibres (CF) from the fibre transporting unit (T) to a three-dimensional shaping structure (S) by means of the flow of air (A) as carrying medium for the cellulose fibres (CF), and arranging the loose and separated cellulose fibres (CF) onto a three-dimensional surface (SSD) of the three-dimensional shaping structure (S) by means of the flow of air (A) for air-forming a three-dimensional body (B) of cellulose fibres (CF), wherein the three-dimensional surface (SSD) of the three-dimensional shaping structure (S) has a shape corresponding to a shape of a three-dimensional pressing surface (SPSD) of the forming mould (M) such that the three-dimensional surface of the three-dimensional shaping structure and at least one three-dimensional pressing surface of the forming mould, have three-dimensional shapes that are similar in configuration, resulting in the forming of a three-dimensional body of cellulose fibres that fits in the forming mould without large deformations; positioning the three-dimensional shaping structure (S) with the airformed three-dimensional body (B) of cellulose fibres (CF) in the forming mould (M); dry-forming the cellulose product (1) into a three-dimensional compressed structure (CSD) in a pressing operation (OP) from the three- dimensional body (B) of cellulose fibres (CF), by pressing and heating the three- dimensional shaping structure (S) with the three-dimensional body (B) of cellulose fibres (CF) in the forming mould (M) with a forming pressure (Pp) and a forming temperature (Tp).

2. The method according to claim 1 , wherein the forming pressure (Pp) is in the range of 1-600 MPa, preferably in the range of 1-100 MPa, more preferably in the range of 4-20 MPa,and the forming temperature (TF) is in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C.

3. The method according to claim 1 or 2, wherein the three-dimensional shaping structure (S) comprises an outer surface (So) and an inner surface (Si), wherein the three-dimensional surface (SSD) is arranged as the outer surface (So) and / or the inner surface (Si), wherein the three-dimensional shaping structure (S) comprises a plurality of suction openings (7) connecting the outer surface (So) and the inner surface (Si), wherein the method further comprises the steps: arranging the loose and separated cellulose fibres (CF) onto the three- dimensional surface (SSD) by means of the flow of air (A) for air-forming the three- dimensional body (B) of cellulose fibres (CF), and applying a negative pressure (PN) via the suction openings (7) for distributing the cellulose fibres (CF) onto the three-dimensional surface (SSD).

4. The method according to any preceding claim, wherein the method further comprises the step: dry-forming the cellulose product (1) in the forming mould (M) from the three-dimensional body (B) of cellulose fibres (CF) in the pressing operation (OP), wherein during dryforming the three-dimensional shaping structure (S) is supporting the three- dimensional body (B) of cellulose fibres (CF), and wherein the cellulose fibres (CF) in the three-dimensional body (B) of cellulose fibres (CF) are integrated into the three-dimensional compressed structure (CSD).

5. The method according to claim 4, wherein the method further comprises the steps: removing the three- dimensional compressed structure (CSD) and the three-dimensional shaping structure (S) from the forming mould (M) after the pressing operation (OP); and separating the three-dimensional compressed structure (CSD) from the three- dimensional shaping structure (S).

6. The method according to any preceding claim,wherein the three-dimensional shaping structure (S) is arranged as a three-dimensional net structure or as a three-dimensional perforated structure.

7. The method according to any preceding claim, wherein the forming mould (M) comprises a first mould part (3a) and a corresponding second mould part (3b), wherein the first mould part (3a) and / or the second mould part (3b) comprises the three-dimensional pressing surface (SPSD), wherein the method further comprises the steps: arranging the three-dimensional shaping structure (S) with the airformed three-dimensional body (B) of cellulose fibres (CF) into a position between the first mould part (3a) and corresponding second mould part (3b); applying the forming pressure (PF) by pressing the three-dimensional shaping structure (S) with the air-formed three-dimensional body (B) of cellulose fibres (CF) between the first mould part (3a) and corresponding second mould part (3b); and applying the forming temperature (TF) onto the three-dimensional shaping structure (S) with the air-formed three-dimensional body (B) of cellulose fibres (CF) in the forming mould (M).

8. The method according to any preceding claim, wherein the method further comprises the step: compacting the three- dimensional body (B) of cellulose fibres (CF) before dry-forming the cellulose product (1) in the forming mould (M).

9. A product forming unit (II) for dry-forming a three-dimensional cellulose product (1) from cellulose fibres (CF), wherein the product forming unit (II) comprises a fibre transporting unit (T) and a forming mould (M), wherein the fibre transporting unit (T) is configured for feeding loose and separated cellulose fibres (CF) from the fibre transporting unit (T) to a three- dimensional shaping structure (S) by means of a flow of air (A) as carrying medium for the cellulose fibres (CF), wherein the loose and separated cellulose fibres (CF) are arranged onto a three-dimensional surface (SSD) of the three- dimensional shaping structure (S) by means of the flow of air (A) for air-forming a three-dimensional body (B) of cellulose fibres (CF),wherein the three-dimensional surface (SSD) of the three-dimensional shaping structure (S) has a shape corresponding to a shape of a three- dimensional pressing surface (SPSD) of the forming mould (M) such that the three- dimensional surface of the three-dimensional shaping structure and at least one three-dimensional pressing surface of the forming mould, have three-dimensional shapes that are similar in configuration, resulting in the forming of a three- dimensional body of cellulose fibres that fits in the forming mould without large deformations, wherein the forming mould (M) is configured for dry-forming the cellulose product (1) into a three-dimensional compressed structure (CSD) in a pressing operation (OP) from the three-dimensional body (B) of cellulose fibres (CF), by pressing and heating the three-dimensional shaping structure (S) with the three-dimensional body (B) of cellulose fibres (CF) with a forming pressure (PF) and a forming temperature (Tp).

10. The product forming unit (II) according to claim 9, wherein the forming pressure (PF) is in the range of 1-600 MPa, preferably in the range of 1-100 MPa, more preferably in the range of 4-20 MPa, and the forming temperature (Tp) is in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C.11 . The product forming unit (II) according to claim 9 or 10, wherein the three-dimensional shaping structure (S) comprises an outer surface (So) and an inner surface (Si), wherein the three-dimensional surface (SSD) is arranged as the outer surface (So) and / or the inner surface (Si), wherein the three-dimensional shaping structure (S) comprises a plurality of suction openings (7) connecting the outer surface (So) and the inner surface (Si).

12. The product forming unit (II) according to any of claims 9 to 11 , wherein the forming mould (M) is configured for dry-forming the cellulose product (1) from the three-dimensional body (B) of cellulose fibres (CF) in the pressing operation (OP), wherein the three-dimensional shaping structure (S) is configured for supporting the three-dimensional body (B) of cellulose fibres (CF), and wherein the cellulose fibres (CF) in the three-dimensional body (B) ofcellulose fibres (CF) are integrated into the three-dimensional compressed structure (CSD).

13. The product forming unit (II) according to any of claims 9 to 12, wherein the three-dimensional shaping structure (S) is arranged as a three-dimensional net structure or as a three-dimensional perforated structure.

14. The product forming unit (II) according to any of claims 9 to 13, wherein the forming mould (M) comprises a first mould part (3a) and a corresponding second mould part (3b), wherein the first mould part (3a) and / or the second mould part (3b) comprises the three-dimensional pressing surface (SPSD), wherein the forming mould (M) is configured for applying the forming pressure (PF) by pressing the three-dimensional shaping structure (S) with the air-formed three-dimensional body (B) of cellulose fibres (CF) between the first mould part (3a) and corresponding second mould part (3b), and wherein the forming mould (M) is configured for applying the forming temperature (TF) onto the three-dimensional shaping structure (S) with the air-formed three-dimensional body (B) of cellulose fibres (CF).

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