Method for producing biogas from fibrous substrates

Abstract

A method for producing biogas from a fibrous substrate, comprising: biological pretreatment by solid-state fermentation using one or more filamentous fungal strains, particularly one or more saprophytic filamentous fungal strains; production of biogas from a woven fabric, nonwoven fabric, or agglomerated and shredded fibrous substrate (with the formation of digestion residue); and recovery of the digestion residue.

Description

Technical Field

[0001] The present invention relates to a method for producing biogas from a fibrous substrate, the method comprising: - biologically pre-treating the fibrous substrate to form a biologically pre-treated fibrous substrate; - transferring the biologically pre-treated fibrous substrate to a biogas production facility; - producing biogas while generating digestion residues from the pre-treated fibrous substrate; - recovering the digestion residues.

Background Art

[0002] Such a biogas production method is well known in the technical field, similar to the case of biogas production from plant waste and wood waste.

[0003] In this case, a biological pretreatment is carried out instead of a mechanical or chemical pretreatment, and an enzyme is used to pretreat the waste in order to promote decomposition by methane-producing microorganisms in the biogas production facility.

[0004] In reality, mechanical / physical or chemical pretreatment is often necessary to obtain biogas production yields that ensure the profitability of a facility. Unfortunately, these pretreatments still require energy resources (crushing, heating, pressurization) and products such as bases (sometimes strong bases) and acids to perform preliminary decomposition of the waste. In the case of chemical treatments, despite considerable efforts to recycle these basic and acidic waste liquids, these treatments still consume water and generate liquid phases that require further treatment. Furthermore, pretreated waste often requires additional treatment (neutralization, heat treatment, etc.) before being introduced into a biogas production facility. For these reasons, some researchers are turning to biological pretreatment using enzymes. While this has proven quite effective in increasing biogas production from waste, it incurs significant additional production costs. Enzymes are relatively expensive, require stringent temperature and pH conditions for optimal function, and carry risks for industrial use, so they are not currently common for most substrates suitable for biogas production. Researchers generally report using them for complex substrates where carbonaceous materials are not readily utilized by bacteria within biogas production facilities.

[0005] Substrates that are difficult to access for carbonaceous materials include not only wood waste but also textile waste, which is a major challenge in waste management.

[0006] In 2021, more than 149 million tons of textile products were produced worldwide. In Europe, textile consumption has increased by more than 40% in the past 20 years, and it is estimated that an average of 11 kg of textile products are discarded per person per year. Of this textile waste, only 38% is collected and sorted with a view to reuse, only 1% is recycled, and it is estimated that 87% is incinerated or sent to landfills.

[0007] One of the main problems with textile waste stems from its diversity. In fact, not only are there different types of waste, but the textile products themselves are also diverse, and the fibers that make them up are also diverse, including blends of various types.

[0008] Regarding textile manufacturing waste (cutting scraps, defective products, production residues, etc.), several solutions currently exist because its properties are clearly understood and managed. However, certain types of textile waste pose significant problems from a recycling perspective.

[0009] Currently, for textile fibers derived from clothing, the existing solution is mechanical sorting to collect resalable garments. For other fibers, advanced sorting aimed at separating fabrics based on composition is performed manually or using fiber optic technology. Textile waste from furniture is not currently recycled and is used as a heat source.

[0010] Furthermore, the blending of synthetic and natural fibers found in mattress covers and other mesh curtains is a source of plastic fibers that cannot be utilized with existing technologies. Although physicochemical treatment methods exist to weaken natural fibers and make them spinnable, they are not currently being effectively utilized.

[0011] In addition, mattress covers are sometimes separated from the mattress itself, but this is not always done and depends on the technical capabilities of the waste disposal center responsible for recycling. Furthermore, some facilities shred mattresses with the ticking still attached, and to remove metal parts, shredded material is produced that is a mixture of shredded ticking and synthetic or natural foam. [Overview of the project] [Problems that the invention aims to solve]

[0012] The present invention aims to overcome the shortcomings of the prior art by providing a method for producing biogas that offers a means of recovering complex waste such as mattress waste, furniture fabric waste, used textile waste, and decorative textile waste. [Means for solving the problem]

[0013] To solve this problem, the present invention provides the biogas production method described at the beginning, characterized in that the biological pretreatment of the fibrous substrate involves solid fermentation of a woven fabric, nonwoven fabric, or agglomerated fibrous substrate using one or more filamentous fungal strains, more specifically one or more saprophytic filamentous fungal strains, and even more specifically strains selected from the Basidiomycota and Ascomycota, wherein the biologically pretreated fibrous substrate is shredded into portions where colonies have formed by one or more fungal strains.

[0014] Thus, the method according to the present invention provides a biological pretreatment for fibrous substrates, which has several advantages. Firstly, pretreatment by solid-state fermentation using one or more strains provides a structural solution that does not require large amounts of water, large amounts of chemicals, or expensive reagents, and does not require significant investment in infrastructure. The strains are known for their ability to digest compounds that are particularly difficult to access, or compounds that are particularly contaminant or toxic, and their action opens up the fibrous structure and promotes the action of methane-producing microorganisms. Furthermore, the strains proliferate by using carbonaceous material as a nutrient source, and as a result produce biomass (i.e., mycelium and other fungal compounds) that is easily digestible by methane-producing microorganisms, thereby reducing the proportion of complex and difficult-to-access fibers in the fibrous substrate. Therefore, after pretreatment with one or more strains, the ratio of complex substrate to digestible substrate becomes more favorable.

[0015] Advantageously, in the method of the present invention, the one or more strains include at least one strain with high colonization ability selected from the group consisting of strains belonging to the genera Agrocybe, Ganoderma, Trametes, Pycnoporus, Pleurotus, Phomes, Phomitopsis, Irpex, Laetiporus, Inonotus, Lentinula, Fusarium, Aspergillus, Trichoderma, Penicillium, Cladosporium, Cetomium, and Acremonium. In particular, species of the genera Agrocybe, Ganoderma, G. aplanatum, G. boninecen, G. lucidum, G. resin, G. cecile, species of the genera Trametes; Trametes hirsuta, T. pubescens, T. suaveolens, T. versicolor, Pycnoporus sanguineus, species of the genera Pleurotus, P. albidas, P. citrinopyreatus, P. jamor, P. eryngii, P. or Streatus, P. ostraceus florida, P. ostraceus sajorcajucaju, P. samoneo stramineus, fumotokitake, akamatsutake, shironamekitake, kitake, oyster mushroom, shiitake; Lepideus lentinus, L. giganteus, L. squalorus, L. tigrinus, a species of Fusarium, Fusarium calmorum, Fusarium solani, a species of Aspergillus, Aspergillus oryzae, Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus, Aspergillus terei, a species of Trichoderma, Trichoderma risei, Trichoderma viride, Trichoderma longibrachiatum, a species of Cladosporum, a species of Cetomium, Cetomium globosum are preferred. This results in fungal strains that spread widely and provide large amounts of biomass that can be used by methane-producing microorganisms for methane production or as a culture substrate. Furthermore, during the colonization process, the fungal strains utilize the carbonaceous material present in the fibrous substrate and begin digesting it. In this way, at least one strain enables the conversion of hard-to-use carbonaceous material into carbonaceous material that can be more readily used by methane-producing microorganisms.

[0016] Advantageously, according to the present invention, the one or more strains include at least one enzyme-producing strain selected from the group consisting of strains belonging to the genera Agrocybe, Ganoderma, Trametes, Pycnoporus, Pleurotus, Phomes, Fomitopsis, Irpex, Laetiporus, Inonotus, Lentinula, Fusarium, Aspergillus, Trichoderma, Penicillium, Cladosporium, Cetomium, and Acremonium, more specifically, a species of Agrocybe, a species of Ganoderma, a species of G. aplanatum, a species of G. boninecen, a species of G. lucidum, a species of G. resin, a species of G. cecile, and a species of Trametes. Species; Trametes hirsuta, T. pubescens, T. suaveolens, T. versicolor, Pycnoporus sanguineus, a species of Pleurotus, P. albidas, P. citrinopyreatus, P. jamor, P. eryngii, P. ostreatus, P. ostraceus florida, P. ostraceus sajorcajucaju, P. samoneostramineus, Pycnoporus samoneus, Pycnoporus matsutake, Pycnoporus sarcocajucaju, P. samoneostramineus, Pycnoporus rufipes, Pycnoporus sarcocajucaju, P. samoneus stramineus, Pycnoporus rufipes, Pycnoporus sarcocajucaju, P. lepideus lentinus, L. giganteus, L. squalorus, L. tigrinus, a species of Fusarium, Fusarium calmorum, Fusarium solani, Aspergillus, The group is selected from strains belonging to Aspergillus oryzae, Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus, Aspergillus terei, a species of Trichoderma, Trichoderma lisey, Trichoderma viride, Trichoderma longibrachiatum, a species of Cladosporum, a species of Cetomium, and Cetomium globosum. In this case, the enzymes produced may have various uses. That is, they may contribute to the breakdown of fibrous substrates, or the enzymes may be a byproduct of the fungal attack on fibrous substrates, which can be recovered, purified, and sold.

[0017] According to the present invention, in some cases, the one or more bacterial strains are assumed to be a mixture of one or more strains having high colonization ability and one or more enzyme-producing bacterial strains.

[0018] In the present invention, "biogas" preferably means gases of biological origin, and in particular refers to gases containing methane, other gases optionally usable as fuel, and carbon dioxide. The latter carbon dioxide is preferably post-treated (recovery, supercritical extraction, reaction with other molecules).

[0019] In a preferred embodiment of the present invention, the aggregated, woven, or nonwoven shredded fiber base material comprises fibers selected from natural plant or animal fibers, semi-synthetic or polymer fibers, and lignocellulose fibers.

[0020] In this specification, natural plant fibers refer to natural fibers such as abaca, bagasse, bamboo, coconut, cotton, flax, hemp, jute, raffia, ramie, rattan, wood, huklaea andina, ceiba pentandra, agave cisarana, kenaf, and piña.

[0021] Natural animal fibers refer to natural animal fibers such as alpaca, angora, bisas, camel hair, cashmere, cat intestines, guanaco, hair or fur, llama, mohair, pashmina, kivik, silk, and in some cases spider silk, tendons, sheep's wool, vicuña, and yak.

[0022] For the purposes of this invention, semi-synthetic fibers refer to fibers such as cellulose acetate, diacetate cellulose, triacetate cellulose, lyocell, and modal.

[0023] Polymer fibers include acrylic fibers, aramid fibers (Twaron®, Kevlar®, Nomex, Technora), microfibers, polyamide fibers, polyester fibers, polyolefin fibers, high molecular weight polyethylene fibers, elastane fibers, Vectran fibers, Vinalon fibers, and Zylon fibers.

[0024] This classification was published by Weidmann in 2010.

[0025] For the purposes of the present invention, lignocellulosic fibers mean fibers derived from forestry, agriculture, waste (such as furniture wood, chipboard, etc.), which contain lignin, hemicellulose and cellulose in various ratios.

[0026] The "fragmented fibrous substrate formed in the form of a woven or non-woven fabric by aggregating the fibers" or the "granular or块状 fibrous substrate composed of the fibers formed in the form of a woven or non-woven fabric by aggregating" usually refers to fibrous or lignocellulosic fibers, and means aggregated woven or non-woven fibers that have undergone a step of reducing the size for granulation. This size reduction includes crushing using a shearing crusher, guillotine cutter, shredder, jaw crusher, or crusher. This crushing step is carried out before the supply of the fibrous substrate. In certain cases, before the wetting step, if it is considered useful, for example, if the particle size distribution of the fibrous substrate in the form of lumps or granules formed from the fibers is too large, or if the average size of the lumps is too large, the present invention also assumes the implementation of an additional size reduction step.

[0027] Preferably, the fibrous substrate in the form of an aggregated woven or non-woven fabric is the crushed residue of recycled fiber products, particularly recycled furniture fiber products, recycled mattresses, bathroom or bedding linen, clothing fiber products, fiber production scraps or waste, upholstery, and mixtures thereof. [[ID=​​​​​​​​​In another embodiment of the present invention, the aggregated fibrous substrate in the form of a woven or nonwoven fabric is, for example, a lignocellulosic elemental fragment, such as chipboard fragments.

[0031] In a preferred embodiment of the present invention, the fibrous base material contains a certain proportion of synthetic fibers, semi-synthetic fibers, synthetic foams such as polyurethane foam, and natural plant fibers or animal fibers, and the recovered digested residue is concentrated with synthetic fibers and plastic materials at a weight ratio of more than 85% relative to the weight of the digested residue.

[0032] In another preferred embodiment of the present invention, the biological pretreatment step is: - A step of preparing a fibrous substrate to obtain a prepared fibrous substrate containing 60-80% by weight of moisture relative to the weight of the prepared fibrous substrate, - A step of sterilizing a prepared fibrous substrate and forming a sterilized and prepared fibrous substrate, - A step of cooling the sterilized and prepared fibrous substrate for a period of 12 to 24 hours, - A step of inoculating the fibrous substrate of the sterilized and prepared mycelial spawn from the one or more seed-bearing mycelial spawns by adding at least one seed-bearing mycelial spawn at a concentration of 0.5% to 10%, more specifically 1% to 7%, more specifically 3% to 5% by weight relative to the weight of the sterilized and prepared fibrous substrate, or by inoculating from a liquid culture of the one or more strains to obtain an inoculated, sterilized and prepared fibrous substrate; - A step of mixing inoculated, sterilized, and prepared fibrous base materials to obtain a homogenized, inoculated, sterilized, and prepared fibrous base material, - A homogenized, inoculated, sterilized, and prepared fibrous substrate is cultured for 1 to 6 weeks, more specifically 2 to 5 weeks, in an environment with a relative humidity of 65-85%, more specifically 70-80%. -The process includes the step of recovering a fibrous substrate on which one or more bacterial strains have formed colonies, and forming a biologically pre-treated fibrous substrate.

[0033] Liquid cultures of one or more of the aforementioned strains are used as inoculation in place of, or in addition to, mycelial spawn.

[0034] In this case, the inoculation concentration is determined to the advantage of those skilled in the art, taking into account the concentration of the starting liquid culture medium and the ability of the bacterial strain to grow on the fibrous substrate to be treated. Typically, 1-5% (by weight) of the liquid culture medium is used for inoculation into a disinfected and prepared fibrous substrate.

[0035] Preferably, in the method according to the present invention, the sterilization treatment of the prepared fibrous substrate is pasteurization to obtain a sterilized and prepared fibrous substrate, and is carried out at a temperature of 72°C or higher for at least 3 hours, preferably at least 4 hours, more preferably at least 5 hours.

[0036] More specifically, in the method according to the present invention, pasteurization is carried out while increasing the temperature, and after reaching a peak temperature of 85°C or higher, more specifically 88°C, and even more specifically 90°C, it is maintained for 5 to 50 minutes, more specifically 30 to 40 minutes.

[0037] In a modified version of the present invention, the sterilization treatment of the prepared fibrous substrate is composting comprising at least one composting cycle, the cycle comprising a step of raising the temperature to between 55°C and 80°C, more preferably a step of raising the temperature until a temperature of 58°C to 65°C is obtained, continuing for 6 hours to 5 days, followed by a step of ventilating the fibrous substrate and maintaining a temperature of 46°C to 49°C for 3 to 7 days, while inverting the fibrous substrate as necessary.

[0038] In a preferred embodiment of the present invention, the step of preparing the fibrous substrate to obtain the prepared fibrous substrate includes the step of wetting the fibrous substrate and / or washing the fibrous substrate, which may be drained or dried as necessary.

[0039] In yet another preferred embodiment of the present invention, the step of preparing the fibrous substrate includes an additional step of supplementing essential elements (minerals (calcium, magnesium), phosphorus, carbon source, nitrogen source, etc.), typically by adding grains, for example, to obtain a fibrous substrate having a carbon:nitrogen ratio in the range of 10 to 30, preferably 15 to 20.

[0040] In another modification of the present invention, sterilization of the prepared fibrous substrate includes at least 2, 3, 4, 5, 6, 7, 8, or 10 consecutive composting cycles.

[0041] In a preferred embodiment of the present invention, the method includes a step of producing biomolecules that are recovered simultaneously with the pretreatment, wherein the one or more strains include at least one biomolecule production strain.

[0042] In an advantageous embodiment of the present invention, the biomolecule is a sugar or polysaccharide, and the at least one strain is selected from the group of strains belonging to the genera Agrocybe, Ganoderma, Trametes, Pycnoporus, Pleurotus, Phomes, Fomitopsis, Irpex, Laetiporus, Inonotus, Lentinula, Fusarium, Aspergillus, Trichoderma, Penicillium, Cladosporium, Cetomium, and Acremonium.

[0043] Examples of polysaccharides produced include, but are not limited to, α-glucan, β-glucan, lentane, lipopolysaccharide, polysaccharide krestin (PSK), polysaccharide peptide (PSP), β-d-glucan, and glucuronoglucan.

[0044] In an advantageous embodiment of the present invention, the biomolecule is a biomolecule or precursor of therapeutic or pharmaceutically interesting, such as an antibiotic, an antimitotic agent, an antiviral agent, a bioadsorbent, or a biosurfactant, and the at least one bacterial strain is selected from, for example, antibiotics, antimitotic agents, antiviral agents, bioadsorbents, biosurfactants, etc.

[0045] For example, Ganoderma fungi are composed of triterpenoids and polysaccharides. Triterpenoids have been reported to exhibit hepatoprotective, antihypertensive, cholesterol-lowering, and antihistamine effects, as well as antitumor, anti-angiogenic, anti-platelet aggregation, and complement inhibitory effects. Examples of triterpenoids include ganodermalic acid, lucidenic acid, ganorcisic acid, apranoxidic acid, lucidimol A and B, ganodermanon diol, ganoderiol F, ganodermanon triol, and lucidone. On the other hand, polysaccharides have also been reported to exhibit antitumor effects through immunomodulation and anti-angiogenesis. Polysaccharides also have a protective effect against free radicals and can reduce cell damage caused by mutagenic substances. Some polysaccharides have also been reported to have antidiabetic effects.

[0046] Trametes versicolor extract exhibits anti-radical, antioxidant, antibacterial, and acetylcholinesterase inhibitory activity.

[0047] Extracts from fungi of the genus Pleurotus exhibit therapeutic effects such as cholesterol reduction, free radical scavenging, antioxidant, anti-atherosclerotic, antitumor, and immunomodulatory properties. For example, fungi of the genus Pleurotus have been reported to contain triterpenoids such as 2,3,6,23-tetrahydroxyurous-12-eno-28-acid, 2,3,23-trihydroxyurous-12-eno-28-acid, and lupeol.

[0048] Pigments derived from fungi of the genus Pycnoporus exhibit antiviral, antibacterial, and anti-inflammatory properties.

[0049] Fungi belonging to the genera Aspergillus, Trichoderma, and Penicillium have been reported to contain biosurfactants.

[0050] Fungi belonging to the genera Penicillium, Acremonium, and Aspergillus have been reported to secrete antibiotics such as penicillin and cephalosporins.

[0051] In another advantageous embodiment of the present invention, the biomolecule is an enzyme, and the at least one strain comprises at least one enzyme-producing strain selected from the group belonging to the genera Agrocybe, Ganoderma, Trametes, Pycnoporus, Pleurotus, Phomes, Fomitopsis, Irpex, Laetiporus, Inonotus, Lentinula, Fusarium, Aspergillus, Trichoderma, Penicillium, Cladosporium, Cetomium, and Acremonium, more specifically a species of Agrocybe, a species of Ganoderma, G. aplanatum, G. boninecen, G. lucidum, G. resin, G. cecile, Trametes Species of the genus Metes; Trametes hirsuta, T. pubescens, T. suaveolens, T. versicolor, Pycnoporus sanguineus, Species of the genus Pleurotus, P. albidas, P. citrinopyreatus, P. jamor, P. eryngii, P. ostreatus, P. ostraceus florida, P. ostraceus sajorcajucaju, P. samoneostramineus, Pycnoporus samoneus, Pycnoporus matsutake, Pycnoporus sarcocajucaju, P. samoneostramineus, Pycnoporus rufipes, Pycnoporus scajucaju, Pycnoporus ostreatus, Pycnoporus lepideus, Pycnoporus scajucaju, Pycnoporus shiitake; Lepideus lentinus, L. giganteus, L. squalorus, L. tigrinus, Species of the genus Fusarium, Fusarium calmorum, Fusarium solani, Aspergillus, The strains are selected from Aspergillus oryzae, Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus, Aspergillus terei, a species of Trichoderma, Trichoderma lissey, Trichoderma viride, Trichoderma longibrachiatum, a species of Cladosporum, a species of Cetomium, and Cetomium globosum.

[0052] More specifically, the enzymes are selected from the group consisting of proteases, laccasses, amylases, cellulases, chitinases, xylanases, manganese peroxidases, lipases, and lignin peroxidases.

[0053] In yet another advantageous embodiment, the biomolecule is an active biomolecule such as an ultraviolet absorber, a dye, an antioxidant, or an anti-radical substance, and the at least one strain comprises at least one strain that produces the active biomolecule and is selected from a group of strains belonging to the genera Pycnopolus, Pleurotus, Trametes, Fusarium, and Ganoderma (for example, Pycnopolus sanguineus, Chitonopireatus, Fusarium oxysporum, Fusarium graminearum, Fusarium fujiirum, Fusarium rece, Trichoderma, Trichoderma risei, Trichoderma viride, Trichoderma longibrachiatum). Examples include Pycnopolus sanguineus, Pleurotus, Fusarium oxysporum, Fusarium graminearum, Fusarium fujikuroi, and Trametes versicolor.

[0054] Examples of pigments include, but are not limited to, cinavalin, cinavaric acid, tramesangine, PsPCP, carmine red anthraquinone, aurofusarin, and bicavelin.

[0055] Other embodiments of the method for producing biogas according to the present invention are shown in the appended claims and the following description as non-limiting examples. [Modes for carrying out the invention]

[0056] The present invention relates to a method for producing biogas from a fibrous substrate, wherein the fibrous substrate is biologically pretreated by solid fermentation using one or more bacterial strains, thereby forming a fibrous substrate in which the one or more bacterial strains have colonized and shredded, and this is then transported to a biogas production facility. After being transported to the biogas production facility, microorganisms within the facility digest (anaerobic digestion) the fibrous substrate in which the one or more bacterial strains have colonized.

[0057] The digested residue produced after biogas production is then collected.

[0058] According to the present invention, it is desirable that the microbial strain rapidly proliferates on a fibrous substrate and has a high ability to establish itself using this substrate as a growth source. This makes it possible to convert carbonaceous substances that are difficult for methane-producing microorganisms to utilize into more readily usable carbonaceous substances. The microbial strain used may also be an enzyme-producing strain. In this case, enzyme production occurs simultaneously with the growth of the microbial biomass, acting synergistically on the decomposition of the fibrous substrate. The enzyme facilitates access for subsequent methane-producing microorganisms.

[0059] In certain embodiments of the present invention, a mixture of multiple strains is selected to optimize the pretreatment of a fibrous substrate with the strains.

[0060] The aggregated, woven, or nonwoven shredded fibrous substrate contains fibers selected from natural plant or animal-derived fibers, semi-synthetic fibers, polymer fibers, and lignocellulose fibers. This preferably includes recycled fiber products, particularly recycled furniture fiber products, recycled mattresses, bathroom or bedding linens, clothing fiber products, fiber production scrap or waste, upholstery, and crushed residues of mixtures thereof. More preferably, it includes crushed residues of recycled fiber products selected from furniture, mattress, and upholstery fiber products, with a synthetic foam content of 10-80%. This residue may also include wood chip residue.

[0061] In particular, for furniture fabrics, mattresses, and upholstery, the composition of the waste is so diverse that there is currently no effective recovery method. Typically, fibrous materials contain a certain proportion of synthetic fibers, semi-synthetic fibers, synthetic foams such as polyurethane (PU) foam, natural plant fibers, or animal fibers.

[0062] While many stakeholders view the presence of synthetic fibers and contamination by plastic foams such as PU foam as disadvantageous because they involve substrates that are difficult to decompose by methane-producing microorganisms, this invention represents a technological breakthrough. This is because, by treating fibrous substrates containing synthetic contaminants as the target of treatment, the digested residue can be concentrated with synthetic and plastic materials, enabling recovery in the field of plastic recycling. According to this invention, the recovered digested residue is concentrated with synthetic fibers and plastic materials at a rate of 85% by weight or more relative to the weight of the digested residue.

[0063] According to the present invention, the biological pretreatment step is: - The steps of preparing a fibrous substrate and obtaining a prepared fibrous substrate containing 60-80% by weight of moisture relative to the weight of the prepared fibrous substrate, - A step of sterilizing the prepared fibrous substrate and forming a sterilized and prepared fibrous substrate. - A step of cooling the sterilized fibrous substrate for a period of 12 to 24 hours, - A step of inoculating a sterilized fibrous substrate with mycelial spawns derived from one or more fungal strains by seed addition, specifically, adding them in a weight ratio of 0.5% to 10% by weight relative to the weight of the sterilized and prepared fibrous substrate, more specifically 1 to 7%, and even more specifically 3 to 5%, in order to obtain an inoculated, sterilized, and prepared fibrous substrate, - A step of mixing inoculated, sterilized, and prepared fibrous base materials to obtain a homogenized, inoculated, and sterilized prepared fibrous base material, - A homogenized, inoculated, sterilized, and prepared fibrous substrate is cultured for 1 to 6 weeks, more specifically 2 to 5 weeks, in an environment with a relative humidity of 65-85%, more specifically 70-80%. -The process includes the steps of recovering a fibrous substrate on which one or more bacterial strains have colonized and forming a biologically pre-treated fibrous substrate.

[0064] This makes it possible to utilize fibrous substrates that are currently not being recovered due to the difficulty in accessing their carbon mass.

[0065] According to the present invention, the sterilization treatment of the prepared fibrous substrate is pasteurization at a temperature of 72°C or higher for at least 3 hours, preferably at least 4 hours, and more preferably at least 5 hours, in order to obtain the prepared fibrous substrate.

[0066] More specifically, in the method according to the present invention, pasteurization is carried out while increasing the temperature, and after reaching a peak temperature above 85°C, more specifically 88°C, and even more specifically 90°C, it is maintained for 5 to 50 minutes, more specifically 30 to 40 minutes.

[0067] In a modified version of the present invention, the sterilization treatment of the prepared fibrous substrate is composting comprising at least one composting cycle, the cycle comprising a step of raising the temperature to between 55°C and 80°C, more preferably a step of raising the temperature to 58°C and 65°C, holding it for a period of 6 hours to 5 days, followed by a step of ventilating the fibrous substrate and maintaining a temperature of 46°C and 49°C for 3 to 7 days. The fibrous substrate may be inverted if necessary.

[0068] Composting effectively provides thorough sterilization of fibrous substrates while eliminating the need for energy-intensive steps.

[0069] In a preferred embodiment of the present invention, the step of preparing a fibrous substrate to obtain a prepared fibrous substrate includes wetting and / or washing the fibrous substrate and continuing with drainage or drying as necessary.

[0070] In yet another preferred embodiment of the present invention, the step of preparing the fibrous substrate includes an additional step of supplementing essential elements (minerals (calcium, magnesium), phosphorus, carbon source, nitrogen source, etc.), typically by adding grains, for example, to obtain a fibrous substrate having a carbon:nitrogen ratio in the range of 10 to 30, preferably 15 to 20.

[0071] In another modification of the present invention, the sterilization treatment of the prepared fibrous substrate includes at least 2, 3, 4, 5, 6, 7, 8, or 10 consecutive composting cycles.

[0072] The method according to the present invention also aims to produce useful biomolecules during biological pretreatment with one or more bacterial strains. In fact, waste recovery is currently carried out on an industrial scale only when it is economically beneficial, such as in terms of energy recovery rate (when the cost of purchasing raw materials is negative, i.e., when waste producers fund the treatment companies) or when it produces economically valuable substances.

[0073] To promote the recycling of textile waste, this invention enables the simultaneous production of high-value biomolecules of interest, which can provide an additional incentive for operators of biogas production units. Depending on the biological pretreatment conditions, these biomolecules can be used for industrial applications (pigments, detergents, etc.), cosmetic applications, pharmaceutical applications, or therapeutic applications.

[0074] The biomolecules that can be manufactured are as described above.

[0075] Alternatively, these biomolecules are preferably selected from enzymes or biomolecules with a molecular weight of less than 5000 daltons, preferably less than 1000 daltons (such as flavorings, surfactants, colorants, and / or terpene derivatives).

[0076] Preferably, these biomolecules are recovered before the biologically pre-treated fibrous substrate is transported to the biogas production facility.

[0077] The present invention is not limited to the embodiments described above, and it is understood that many modifications are possible without departing from the scope of the appended claims.

Claims

1. A method for producing biogas from a fibrous substrate, The aforementioned method, - The step of biologically pre-treating the fibrous substrate to form a biologically pre-treated fibrous substrate, - A step of transferring the biologically pre-treated fibrous substrate to a biogas production facility, - A step of producing biogas from the pre-treated fibrous substrate while generating digestion residue, - The step of collecting the digested residue, Includes, The biological pretreatment of the fibrous substrate involves solid fermentation of a woven fabric, nonwoven fabric, or agglomerated fibrous substrate using one or more filamentous fungal strains, more specifically, one or more saprophytic filamentous fungal strains, thereby shredding the biologically pretreated fibrous substrate into portions where the one or more fungal strains have formed colonies.

2. The method according to claim 1, wherein the one or more strains include at least one strain having high colonization ability, selected from the group consisting of strains belonging to the genera Agrocybe, Ganoderma, Trametes, Pycnoporus, Pleurotus, Phomes, Phomitopsis, Irpex, Laetiporus, Inonotus, Lentinula, Fusarium, Aspergillus, Trichoderma, Penicillium, Cladosporium, Cetomium, and Acremonium.

3. The method according to claim 1 or 2, wherein the one or more strains include at least one enzyme-producing strain selected from the group consisting of strains belonging to the genera Agrocybe, Ganoderma, Trametes, Pycnoporus, Pleurotus, Phomes, Phomitopsis, Irpex, Laetiporus, Inonotus, Lentinula, Fusarium, Aspergillus, Trichoderma, Penicillium, Cladosporium, Cetomium, and Acremonium.

4. The method according to any one of claims 1 to 3, wherein the one or more strains are a mixture of one or more strains having high colonization ability and one or more enzyme-producing strains.

5. The method according to any one of claims 1 to 4, wherein the aggregated, shredded fibrous base material of a woven or nonwoven fabric comprises fibers selected from natural plant or animal fibers, semi-synthetic or polymer fibers, and lignocellulose fibers.

6. The method according to any one of claims 1 to 5, wherein the aggregated, shredded fibrous base material of a woven or nonwoven fabric is a recycled textile product, more specifically a recycled furniture textile product, a recycled mattress, linens for bathrooms or bedding, a textile product for clothing, scraps or waste from the manufacture of textile products, upholstery, and residues from the crushing of mixtures thereof.

7. The method according to any one of claims 1 to 6, wherein the aggregated fibrous base material in the form of a woven or nonwoven fabric is a crushed residue of regenerated fibers selected from furniture, mattress and upholstery fibers, and has a synthetic foam content in the range of 10% to 80%.

8. The method according to any one of claims 1 to 7, wherein the aggregated fibrous base material in the form of a woven or nonwoven fabric is, for example, a pulverized residue of a lignocellulosic element such as the crushed residue of particleboard.

9. The method according to any one of claims 1 to 8, wherein the fibrous base material contains synthetic fibers, semi-synthetic fibers, synthetic foams such as polyurethane foam, and natural plant fibers or animal fibers in a certain proportion, and the recovered digested residue is concentrated with synthetic fibers and plastic materials at a weight ratio of more than 85% relative to the weight of the digested residue.

10. The step of biologically pre-treating the fibrous substrate is: - The steps of preparing the fibrous base material and obtaining a prepared fibrous base material containing 60 to 80% by weight of moisture relative to the weight of the prepared fibrous base material, - A step of sterilizing the prepared fibrous base material and forming a sterilized and prepared fibrous base material, - A step of cooling the sterilized and prepared fibrous substrate for a period of 12 to 24 hours, - A step of inoculating the fibrous substrate of the sterilized and prepared mycelial spawn from the one or more seed-bearing mycelial spawns by adding at least one seed-bearing mycelial spawn at a concentration of 0.5% to 10%, more specifically 1% to 7%, more specifically 3% to 5% by weight relative to the weight of the sterilized and prepared fibrous substrate, or by inoculating from a liquid culture of the one or more strains, thereby obtaining a fibrous substrate that has been inoculated, sterilized, and prepared from the one or more seed-bearing mycelial spawns, - A step of mixing the inoculated, sterilized, and prepared fibrous base material to obtain a homogenized, inoculated, sterilized, and prepared fibrous base material, - A step of culturing the homogenized, inoculated, sterilized, and prepared fibrous substrate in an environment with a relative humidity of 65-85%, more specifically 70-80%, for a period of 1-6 weeks, more specifically 2-5 weeks. - A step of collecting a fibrous substrate on which one or more bacterial strains have formed colonies, and forming the biologically pre-treated fibrous substrate, The method according to any one of claims 1 to 9, including the method described in any one of claims 1 to 9.

11. The method according to claim 10, wherein the sterilization is steam sterilization, and a fibrous substrate is obtained by sterilizing at a temperature of 72°C or higher for at least 3 hours, preferably at least 4 hours, more preferably at least 5 hours.

12. The method according to claim 11, wherein the sterilization treatment is carried out while increasing the temperature, and after reaching a peak temperature of over 85°C, more specifically 88°C, and even more specifically 90°C, it is maintained for 5 minutes to 50 minutes, more specifically 30 minutes to 40 minutes.

13. The method according to any one of claims 10 to 12, wherein the sterilization treatment of the prepared fibrous substrate is composting comprising at least one composting cycle, the cycle comprising a step of raising the temperature until a temperature of 55°C to 80°C is obtained, more preferably a step of raising the temperature for a period of 6 hours to 5 days until a temperature of 58 to 65°C is obtained, and then a step of ventilating the fibrous substrate and maintaining a temperature of 46 to 49°C for 3 to 7 days, and inverting the fibrous substrate as necessary.

14. The method according to any one of claims 10 to 13, wherein the step of preparing the fibrous substrate to obtain the prepared fibrous substrate includes a step of wetting and / or washing the fibrous substrate, and optionally a step of draining or drying it.

15. The method according to any one of claims 10 to 14, wherein the step of preparing the fibrous base material includes an additional step of supplementing essential elements such as minerals (calcium, magnesium), phosphorus, a carbon source and a nitrogen source, and by adding grain, for example, a fibrous base material is obtained in which the carbon:nitrogen ratio is typically 10 to 30, preferably 15 to 20.

16. The method according to any one of claims 1 to 15, comprising a step of generating a biomolecule simultaneously with pretreatment, wherein the one or more bacterial strains include at least one biomolecule-producing strain.

17. The method according to claim 16, wherein the biomolecule is a sugar or polysaccharide, and the at least one strain comprises at least one sugar or polysaccharide producing strain selected from the group of strains of the genera Ganoderma, Trametes, and Pleurotus, such as Ganodermarcidosum.

18. The method according to claim 16, wherein the biomolecule is, for example, a biomolecule of therapeutic or pharmaceutical interest such as an antibiotic, an antimitotic agent, an antiviral agent, a bioadsorbent, or a surfactant, and the at least one bacterial strain is selected from, for example, an antibiotic, an antimitotic agent, an antiviral agent, a bioadsorbent, or a surfactant.

19. The method according to claim 16, wherein the biomolecule is an enzyme, and the at least one strain comprises at least one enzyme-producing strain selected from the group of strains belonging to the genera Agrocybe, Ganoderma, Trametes, Pycnoporus, Pleurotus, Phomes, Phomitopsis, Irpex, Leitiporus, Inonotus, Lentinula, Fusarium, Aspergillus, Trichoderma, Penicillium, Cladosporium, Cetomium, and Acremonium.

20. The method according to claim 16, wherein the biomolecule is an active biomolecule such as a UV filter, dye, antioxidant, or anti-radical substance, and the at least one strain comprises at least one strain that produces an active biomolecule and is selected from the group of strains belonging to the genera Pycnopolus, Pleurotus, Trametes, Fusarium, and Ganoderma, such as Pycnopolus sanguineus, Pleurotus citrinopyreatus, Fusarium oxysporum, Fusarium graminearum, Fusarium fujicroi, and Trametes versicolor.

21. The method according to claim 16, wherein the biomolecule is a surfactant.

22. The method according to any one of claims 1 to 21, wherein the recovered digested residue is inactivated, particularly by using heat, and formed, for example, into blocks, modules, or panels.

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