Process for producing an additive material, in particular in the field of paper production or the production of plastic material, an additive material obtained from said process and a product comprising said additive material

Abstract

A process for producing an additive material (MA), in particular in the field of paper production or the production of plastic materials; the process comprises the following steps: providing an agri-food material (M1); carrying out a first drying of the agri-food material (M1) by reducing the moisture content below 20%, in particular below 10%; grinding the agri-food material (M1); sieving the agri-food material (M1) to separate the agri-food material (M1) that has a particle size (DG) lower than 2 mm, in particular lower than 1 mm, more in particular lower than 0.7 mm; and pelletising the agri-food material (M1).

Description

[0001] PROCESS FOR PRODUCING AN ADDITIVE MATERIAL , IN PARTICULAR IN THE FIELD OF PAPER PRODUCTION OR THE PRODUCTION OF PLASTIC MATERIAL , AN ADDITIVE MATERIAL OBTAINED FROM SAID PROCESS AND A PRODUCT COMPRISING SAID ADDITIVE MATERIAL

[0002] Cross-Reference to Related Applications

[0003] This Patent Application claims priority from Italian Patent Application No . 102023000025551 filed on November 30 , 2023 , the entire disclosure of which is incorporated herein by reference .

[0004] Technical Field

[0005] The present invention relates to a process for producing an additive material , an additive material obtained from said process and a product comprising said additive material .

[0006] The invention is advantageously applied (without thereby losing generality) in the production of additives to be utilised in the field of paper production or the production of plastic material , in particular plastic composites .

[0007] Prior Art

[0008] In the sector of the paper industry, i . e . in paper production, the fibres traditionally used include cellulose fibres from wood (with long or short fibres ) and recycling paper .

[0009] It is also known to use in the sector of the paper industry or the plastic materials industry alternative fibres deriving from agri- food waste .

[0010] The alternative fibres used so far are subj ected to a drying and grinding process before being added to the mixture for the production of paper . However, in general , these alternative fibres are mainly exclusively utilised as fillers . Therefore , they do not signi ficantly contribute to strength or mechanical resistance which, as is known, depends on the length of the fibres of the paper ( in particular of the final paper sheet ) produced . In other words , the alternative fibres are often utilised only as fillers , and cannot form a signi ficant part of the mixture , mainly due to the other components present in the agri- food waste , which limit the use thereof at high levels .

[0011] W02008073186A2 relates to the processing of biomass and products derived therefrom .

[0012] US2010196981A1 relates to a method and a system for producing raw materials from slurry .

[0013] CN112515222A relates to a method for the j oint production of paper pulp and fodder utilising vegetable fibres as a raw material .

[0014] Description of the Invention

[0015] The obj ect of the present invention is to provide a process for producing an additive material , in particular in the field of paper production or the production of plastic material , an additive material obtained from said process and a product comprising said additive material which are free from the drawbacks of the state of the art and which are easy and cost-ef fective to produce .

[0016] According to the present invention, a process for producing an additive material is provided, in particular in the field of paper production or the production of plastic material , as claimed in the following independent claims and, preferably, in any of the claims directly or indirectly dependent on the independent claims .

[0017] In addition, according to the present invention, an additive material is provided, in particular in the field of paper production or the production of plastic material , as claimed in the following independent claims and, preferably, in any of the claims directly or indirectly dependent on the independent claims .

[0018] In addition, according to the present invention, a product is provided, in particular in the field of paper production or the production of plastic material , as claimed in the following independent claims and, preferably, in any of the claims directly or indirectly dependent on the independent claims .

[0019] The claims describe preferred embodiments of the present invention forming integral part of the present description .

[0020] Brief Description of the Drawings

[0021] The present invention will now be described with reference to the accompanying drawings , which illustrate two non-limiting embodiments of the process :

[0022] - Figure 1 is a schematic diagram depicting the various steps of a first embodiment of the process in particular belonging to the state of the art ; and

[0023] - Figure 2 is a schematic diagram depicting the various steps of a second embodiment of the process according to the present invention .

[0024] Preferred Embodiments of the Invention

[0025] Figures 1 and 2 schematically il lustrate , by means of a block diagram, the various steps, according to different embodiments, of a process for producing an additive material MA (also known as filler or substitute material) . The additive material MA is configured to be used, in particular in the field of paper production or the production of plastic material [which in the following discussion is understood as both traditional plastics (such as polyethylene, polypropylene, polylactic acid, polyhydroxybutyrate - virgin or recycled) , and bioplastics] .

[0026] In the following discussion, the term "agri-food material" means a cultivated, produced and processed material of agricultural products intended for nutrition. In particular, the agri-food material Ml used in the process in question is a waste of the agri-food chain. Preferably, the agri-food material Ml comprises at least one material chosen from (non-exhaustive list) : brewers' grains, bran from industrial cereal processing (for example in bread and pasta processing) , jute, hemp, flax, coffee processing waste (for example the coating of the bean (also known as silverskin) , used coffee, coffee grounds) , egg shells, citrus pulp, fruit and vegetable processing waste or a combination thereof.

[0027] In the accompanying figures, a process for producing the additive material MA is provided (the steps of which are schematically indicated in the block diagram) . Preferably, but not limitedly, the sequence for performing the steps of the process is defined by the order described herein in the following .

[0028] The process comprises a step (not illustrated) of providing an agri-food material Ml. The process comprises a step (indicated in the accompanying figures as step A) of carrying out a first drying of the agri-food material Ml by reducing its moisture content below 20%, in particular below 10%.

[0029] The process comprises a step (indicated in the accompanying figures as step B) of grinding the (in particular dried) agri-food material Ml, so as to obtain a ground agri-food material Ml. In other words, in this step the agri-food material Ml (preferably, dried in step A) is ground, so as to reduce its particle size DG. The term "particle size" means the size of the particles (i.e. of the pieces into which it has been fragmented) of the agri-food material Ml. The ground material Ml is substantially a powder. In the case where the agri-food material Ml comprises a combination of at least two agri-food materials, then the step of grinding the materials Ml preferably comprises a sub-step of homogenising (i.e. amalgamating) the ground agri-food material Ml, so as to obtain a ground agri-food material Ml with a homogeneous (in particular uniform) distribution of the two or more ground agri-food materials.

[0030] The process comprises a step (indicated in the accompanying figures as step C) of sieving the agri-food material Ml ground in step B, so as to separate the agri- food material Ml that has a particle size DG that is less than a predefined particle size DGP . The predefined particle size DGP is lower than 2 mm, in particular than 1 mm, more in particular than 0.7 mm. In other words, in this step the agri-food material Ml is sieved by means of a separating device (such as a filter, a sieve, a screen) . The separating device (of known type and thus not described in detail) comprises a separation mesh, each of which has a size equal to the predefined particle size DGP (which as previously described is lower than 2 mm, in particular than 1 mm, more in particular than 0.7 mm) , so as to separate the agri-food material Ml that has the particle size DG less than the predefined particle size DGP (which continues the process) , from the agri-food material Ml that has the particle size DG greater than the predefined particle size DGP (which is discarded) . According to a possible alternative (which is optional) and is illustrated by a dashed line in Figures 1 and 2, the agri-food material Ml that has the particle size DG greater than the mesh size (i.e. greater than the predetermined particle size DGP) , which is thus separated from the remaining amount of agri-food material Ml and is returned to the grinding step (i.e. the previously described step B) to be again subjected to the grinding step.

[0031] The process comprises a step (indicated in the accompanying figures as step H) of pelletising the agri-food material Ml, in particular sieved in the sieving step C. In other words, in this step the agri-food material Ml, which preferably comes from the sieving step, is agglomerated to obtain the additive material MA.

[0032] Preferably, but not limitedly, the step of carrying out the first drying of the agri-food material Ml occurs upstream of the step of grinding the agri-food material Ml. This allows improving the grinding, as the risk of clogging the grinding device is drastically reduced.

[0033] Between the sieving step and the pelletising step, the process comprises the steps D-G indicated in the following. Preferably, but not limitedly, the performing sequence is defined by the order described herein in the following.

[0034] The process further comprises a step (indicated in the accompanying figures as step D) of treating the agri-food material Ml (specifically the part having the particle size less than the predetermined particle size DGP) with an acidic or basic aqueous solution (as it will be described in the following) . In particular, the aqueous solution comprises (in particular consists of) : a quaternary ammonium salt and an organic acid. Alternatively, the aqueous solution comprises (in particular consists of) a quaternary ammonium salt and another organic molecule. In particular, the quaternary ammonium salt comprises at least one chosen from:

[0035] 2-hydroxy-N, N, N-trimethylethanammonium chloride, 2-hydroxy- N,N, N-trimethylethanammonium chloride) ; and / or the organic acid comprises at least one chosen from: 2-hydroxyethanoic acid, 4-oxopentanoic acid, 2S-hydroxy-l , 4-butanedioic acid,

[0036] 3-carboxy-3-hydroxy-l , 5-pentanedioic acid, ethanoic acid or a combination thereof; and / or the other organic molecule comprises at least one chosen from: 1,3 diazole, diaminomethanone or a combination thereof.

[0037] Advantageously, the aqueous solution comprises between 25% to 75% of water and the remaining part (in particular between 75% and 25%) of quaternary ammonium salt, of organic acid or of the other organic molecule.

[0038] Advantageously, the amount of aqueous solution added in the step of treating the agri-food material Ml is between 3 and 20% by weight, preferably substantially equal to 10% by weight , with respect to the agri- food material Ml to be treated .

[0039] The process comprises a step ( indicated in the accompanying figures as step E ) of adj usting the pH of the treated agri- food material Ml , in particular as indicated in the previously described step D, so as to reach a predetermined pH, which is defined depending on the chemical composition of the agri- food material Ml . This step allows selectively solubilis ing some components ( such as lignin, hemicellulose and pectin) present to puri fy the cellulose fibre present . Advantageously, the step of treating the agri- food material Ml is carried out downstream of the sieving step and upstream of the step of adj usting the pH .

[0040] The process comprises a step ( indicated in the accompanying figures as step F) of washing the treated agri- food material Ml with a washing fluid, in particular water, in such a way that the pH is modi fied until a neutral pH (which is known to be a pH substantially equal to 7 ) is reached .

[0041] Advantageously, but not limitedly, the process can comprise a step of mixing the material Ml for a given period of time (preferably between 3 and 8 hours , depending on the processed agri- food material Ml ) and at a given temperature (preferably below 100 ° C, in particular equal to 50 ° C, depending on the processed agri- food material Ml ) . The step of mixing the material Ml preferably occurs downstream of the step of adj usting the pH and upstream of the step of washing the material Ml .

[0042] Advantageously, but not limitedly, upstream of the step of washing the material (and in particular downstream of the mixing step - if present) there is a step of filtering the agri-food material Ml.

[0043] The process comprises a step (indicated in the accompanying figures as step G) of carrying out a second drying of the agri-food material Ml, preferably (but not necessarily) washed, by reducing the moisture content below 20%, in particular below 10%. In other words, the agri-food material Ml, in particular after having been subjected to washing as indicated in the previously described step F, is again dried so as to bring the moisture content below 20%, in particular below 10%. The step of carrying out the second drying is a different and additional step with respect to the step of carrying out a first drying.

[0044] According to a further aspect of the present invention, also the additive material MA obtained (i.e. produced) by applying the previously described production process is provided. The additive material MA thereby produced is configured to be admixed (i.e. added) to the mixture for the production of paper or plastic material.

[0045] Preferably, but not limitedly, the additive material MA has a spherical or cylindrical shape.

[0046] Advantageously, the additive material MA has a size between 3 and 30 mm.

[0047] According to an additional aspect of the present invention, a product (manufactured product which can be a semi-finished or finished product) made of paper and comprising the additive material MA, produced by applying the previously described production process, is provided. The product comprises an amount of additive material MA between 1 and 70% by weight.

[0048] According to an additional aspect of the present invention, a product made of plastic material and comprising the additive material MA, produced by applying the previously described production process, is provided. The product comprises an amount of additive material MA between 5 and 90% by weight.

[0049] The term "semi-finished" also means a mixture of paper material or plastic material comprising the additive material MA not yet moulded.

[0050] In the following, some laboratory examples are described (which are purely exemplifying and not limiting) and which have the purpose of clarifying the different previously described steps of the process.

[0051] EXAMPLE 1:

[0052] Providing 1 ton of agri-food material Ml comprising (in particular consisting of) beer production waste (brewers' grains) that is dried until reaching a moisture content between 6% and 12%, ground, sieved (particle size DG lower than 0.7 mm) . The agri-food material Ml that has the particle size lower than 0.7 mm is finally pelletised.

[0053] The additive material MA obtained can be utilised in place of the traditional cellulose in paper production in varying percentages, between 1% and 70% by weight.

[0054] Alternatively, the additive material MA obtained can be utilised in place of (virgin or recycled) plastic materials in the production of products made of plastic or bioplastic material in varying percentages between 5% and 90% by weight. EXAMPLE 2:

[0055] Providing 100 g of agri-food material Ml comprising (in particular consisting of) beer production waste (brewers' grains) that is dried until reaching a moisture content between 6% and 12%, ground and sieved (particle size DG lower than 0.7 mm) . The agri-food material Ml that has the particle size lower than 0.7 mm is treated with 1000 g of an aqueous solution (50% by weight) , comprising 270 g of 2- (hydroxyethyl ) trimethylammonium chloride and 230 g of diaminomethanone . The pH of the solution is adjusted to pH 9. After a period of time, in particular 6 hours, the agri- food material Ml that has the particle size lower than 0.7 mm is filtered and washed with water up to neutral pH. The agri-food material Ml that has the particle size lower than 0.7 mm is then dried and finally pelletised.

[0056] The additive material MA obtained can be utilised in place of traditional cellulose in paper production in varying percentages between 1% and 70% by weight.

[0057] Alternatively, the additive material MA obtained can be utilised in place of (virgin or recycled) plastic materials in the production of products made of plastic or bioplastic material in varying percentages between 5% and 90% by weight.

[0058] EXAMPLE 3:

[0059] Providing 100 g of agri-food material Ml comprising (in particular consisting of) egg shell waste that is dried until reaching a moisture content between 6% and 12%, ground and sieved (particle size DG lower than 0.7 mm) . The agri-food material Ml that has the particle size lower than 0.7 mm is finally pelletised. The additive material MA obtained can be utilised in place of the traditional cellulose in paper production in varying percentages between 1% and 20% by weight.

[0060] EXAMPLE 4 :

[0061] Providing 1 ton of agri-food material Ml comprising (in particular consisting of) cereal grinding waste (bran) that is dried until reaching a moisture content between 6% and 12%, ground and sieved (particle size DG lower than 0.7 mm) . The agri-food material Ml that has the particle size lower than 0.7 mm is finally pelletised.

[0062] The additive material MA obtained can be utilised in place of the traditional cellulose in paper production in varying percentages between 1% and 70% by weight.

[0063] Alternatively, the additive material MA obtained can be utilised in place of (virgin or recycled) plastic materials in the production of products made of plastic or bioplastic material in varying percentages between 5% and 90% by weight.

[0064] EXAMPLE 5:

[0065] Providing 100 g of agri-food material Ml comprising (in particular consisting of) cereal grinding waste (bran) that is dried until reaching a moisture content between 6% and 12%, ground and sieved (particle size DG lower than 0.7 mm) . The agri-food material Ml that has the particle size lower than 0.7 mm is treated with 1000 g of an aqueous solution (50% by weight) , comprising 340 g of 2- (hydroxyethyl ) trimethylammonium acetate and 160 g of 2- hydroxyethanoic acid. The pH of the solution is adjusted to pH 4. After a period of time, in particular 4 hours of mixing at room temperature, the agri-food material Ml that has the particle size lower than 0.7 mm is filtered and washed with water up to neutral pH. The agri-food material Ml that has the particle size lower than 0.7 mm is then dried and finally pelletised .

[0066] The additive material MA obtained can be utilised in place of the traditional cellulose in paper production in varying percentages between 1% and 70% by weight.

[0067] Alternatively, the additive material MA obtained can be utilised in place of (virgin or recycled) plastic materials in the production of products made of plastic or bioplastic material in varying percentages between 5% and 90% by weight.

[0068] EXAMPLE 6:

[0069] Providing 50 g of agri-food material Ml comprising (in particular consisting of) waste from the transport bags of green coffee (which are typically made of jute) that is ground and sieved (particle size DG lower than 0.7 mm) . The agri-food material Ml that has the particle size lower than 0.7 mm is treated with 1000 g of an aqueous solution, comprising 290 g of 2- (hydroxyethyl ) trimethylammonium acetate and 136 g of hydroxyethanoic acid. The pH of the solution is adjusted to pH 4. After a period of time, in particular 2 hours of mixing at 80°C, the agri-food material Ml that has the particle size lower than 0.7 mm is filtered and washed with water up to neutral pH. The agri-food material Ml that has the particle size lower than 0.7 mm is dried and finally pelletised.

[0070] This pellet can be utilised in place of the traditional cellulose in paper production in varying percentages between 1% and 70% by weight. Or it can be utilised in place of (virgin or recycled) plastic materials in the production of products made of plastic or bioplastic material in varying percentages between 5% and 90%.

[0071] EXAMPLE 7:

[0072] Providing 1 ton of agri-food material Ml comprising (in particular consisting of) pectin production waste (known as pulp) that is dried until reaching a moisture content between 6% and 12% and sieved (particle size DG lower than 0.7 mm) . The agri-food material Ml that has the particle size lower than 0.7 mm is finally pelletised.

[0073] The additive material MA obtained can be utilised in place of the traditional cellulose in paper production in varying percentages between 1% and 70% by weight.

[0074] Alternatively, the additive material MA obtained can be utilised in place of (virgin or recycled) plastic materials in the production of products made of plastic or bioplastic material in varying percentages between 5% and 90% by weight.

[0075] EXAMPLE 8:

[0076] Providing 100 g of agri-food material Ml comprising (in particular consisting of) used coffee that is ground and sieved (particle size DG lower than 0.7 mm) . The agri-food material Ml that has the particle size lower than 0.7 mm is treated with 1000 g of an aqueous solution (50% by weight) , comprising 290 g of 2- (hydroxyethyl ) trimethylammonium acetate and 210 g of diaminoethanone. The pH of the solution is adjusted to pH 10. After a period of time, in particular 8 hours of mixing at 80°C, the agri-food material Ml that has the particle size lower than 0.7 mm is filtered and washed with water up to neutral pH . The agri- food material Ml that has the particle si ze lower than 0 . 7 mm is then dried and finally pelletised .

[0077] The additive material MA obtained can be utilised in place of (virgin or recycled) plastic materials in the production of products made of plastic or bioplastic material in varying percentages between 5% and 90% by weight .

[0078] The production process , the additive material MA and the product comprising the additive material MA described so far have a plurality of advantages .

[0079] Firstly, the process allows producing the additive material MA that can be utilised for the production of paper with di f ferent percentages (preferably by weight ) depending on the type of paper to be produced . In particular, it is possible to produce disposable paper, also known as tissue ( such as face wipes , toilet paper, disinfectant wipes , paper napkins or paper towels ) comprising up to 40% (preferably, up to 30% ) of additive material MA. The percentage ( in particular by weight ) of the additive material MA can be increased up to 80% (pre ferably up to 70 ) in the production of rigid paper such as in the paper-making and corrugated cardboard field .

[0080] In particular, with reference to the paper production sector, the process allows obtaining an additive material MA for paper production in an ef ficient and sustainable way, providing an innovative solution for the paper industry and which contributes to reducing deforestation as a valid alternative to virgin fibres coming from wood .

[0081] The process also has the advantage of producing an additive material MA that can be used in the field of the production of plastic materials that can be admixed to di f ferent (virgin or recycled) plastic materials such as polyethylene , polypropylene , PBA, PHB at varying percentages ( in particular by weight ) . Such variables are preferably between 5% and 90% . The admixed plastic material of the additive material MA can be moulded with di f ferent moulding technologies (non-exhaustive list : inj ection moulding, extrusion moulding, blow moulding or rotational moulding) .

[0082] Thanks to the steps of treating the agri- food material Ml , the step of adj usting the first pH and the washing step, the agri- food material Ml is cleaned of components that can interfere with paper production . For this reason, the process described so far has the advantage of having an alternative pulp ( i . e . the additive material MA) that can be admixed to the paper mixture up to high percentages , as previously described .

[0083] The additive material MA produced ( i . e . obtained) according to the previously described process has the further advantage of contributing to increase the mechanical resistance of the product produced therefrom .

[0084] The process also has the advantage of preserving the proteins and / or the pectin and / or the hemicellulose contained ( compri sed) in the material Ml . In particular, it has been found that the preservation of proteins and / or pectin and / or hemicellulose (which we recall are el iminated in the process of known type ) and which are comprised within the additive material MA allow, regardless of the length of the fibre , increas ing the mechanical resistance of the product . In other words , laboratory tests have shown that by increasing the amount of proteins and / or pectin and / or hemicellulose comprised in the agri- food material Ml ( and therefore the additive material MA obtained therefrom) it is possible to increase the percentage by weight of additive material MA to be added to the mixture for the production of paper, simultaneously improving the mechanical resistance thereof . In addition, the laboratory tests carried out have shown that also in the field of processing plastic material , similar to that of paper, it is possible to increase the percentage by weight of additive material MA to be added to the mixture for the production of plastic material , simultaneously improving the mechanical resistance thereof . Also in this case , the additive material MA can be added to the mixture in place of the (virgin or recycled) plastic materials .

Claims

C L A I M S1. A process for producing an additive material (MA) , in particular in the field of paper production or the production of plastic materials; the process comprises the following steps:- providing an agri-food material (Ml) ;- carrying out (A) a first drying of the agri-food material (Ml) by reducing the moisture content below 20%, in particular below 10%; grinding (B) the, in particular dried, agri-food material (Ml ) ;- sieving (C) the ground agri-food material (Ml) to separate the agri-food material (Ml) that has a particle size (DG) that is less than a predefined particle size (DGP) lower than 2 mm, in particular lower than 1 mm, more in particular lower than 0.7 mm;- pelletising (H) the, in particular sieved, agri-food material (Ml ) ; the method is characterised in that between the step of sieving (C) and the step of pelletising (H) the agri-food material (Ml) , the process comprises the further steps:- treating (D) with an acidic or basic aqueous solution;- adjusting (E) a first pH of the treated agri-food material (Ml) to reach a predetermined pH, depending on the chemical composition of the agri-food material (Ml) ; wherein the first pH is acidic or basic;- washing (F) the treated agri-food material (Ml) with a washing fluid, in particular water, in such a way that the first pH is modified until a second pH is reached; whereinthe second pH is neutral; and- carrying out (G) a second drying of the agri-food material (Ml) by reducing the moisture content below 20%, in particular below 10%.

2. The process according to claim 1, wherein the amount of aqueous solution added in the treating step to the agrifood material (Ml) is between 3% and 20% by weight, preferably substantially equal to 10% by weight, with respect to the agri-food material (Ml) to be treated.

3. The process according to claim 1 or 2, wherein the aqueous substance used in the treating step (D) comprises: a quaternary ammonium salt and an organic acid; or a quaternary ammonium salt and another organic molecule; wherein : the quaternary ammonium salt comprises at least one chosen from: 2-hydroxy-N, N, N-trimethylethanammonium chloride, 2- hydroxy-N, N, trimethylethanammonium chloride; and / or the organic acid comprises at least one chosen from: 2- hydroxyethanoic acid, 4-oxopentanoic acid, 2S-hydroxy-l , 4- butanedioic acid, 3-carboxy-3-hydroxy-l , 5-pentanedioic acid, ethanoic acid or a combination thereof; and / or the organic molecule comprises at least one chosen from: 1,3 diazole, diaminomethanone or a combination thereof.

4. The process according to any one of the preceding claims, wherein the step (A) of a first drying of the agri- food material (Ml) occurs upstream of the step (B) of grinding the agri-food material (Ml) .

5. The process according to any one of claims 1 to 4, wherein the step of treating (D) the agri-food material (Ml)is carried out downstream of the step (C) of sieving and upstream of the step of adjusting the first pH.

6. The process according to any one of the preceding claims, wherein the agri-food material (Ml) comprises at least one material chosen from: brewers' grains, bran from industrial cereal processing, jute, hemp, flax, coffee processing waste, egg shells, citrus pulp, fruit and vegetable processing waste, or a combination thereof.

7. An additive material (MA) obtained by applying the production process according to any one of claims 1 to 6; wherein the additive material (MR) has a spherical or cylindrical shape.

8. A product made of paper and comprising an amount between 1 and 70% by weight of an additive material (MA) ; wherein the additive material (MA) is made by applying the production process according to any one of claims 1 to 6.

9. A product made of plastic material and comprising an amount between 5 and 90% by weight of an additive material (MA) ; wherein the additive material (MA) is made by applying the production process according to any one of claims 1 to 6.

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