A method for graded utilization of all components of Reed sphagnum moss guided by segmented fiber breaking

Abstract

This invention is a method for the graded utilization of all components of Arundo donax through segmented fiber crushing. This method, through the coordinated design of front-end and back-end processes, systematically couples customized agronomic front-end processes, differentiated component separation paths, and a shared environmentally friendly purification platform to achieve the joint production of multiple series of high-value products from a single Arundo donax raw material. The method includes the following steps: customized production and supply of targeted raw materials; differentiated separation and pretreatment of whole-plant components; and high-value conversion of components based on the shared purification platform: high-value conversion of leaves to obtain high-purity Arundo donax flavonoids and Arundo donax leaf powder; separation and derivatization of the three culms to obtain xylose / syrup and high-purity lignin, as well as further derivatization to prepare various bio-based chemicals and bio-based materials, including lactide, polylactic acid resin, nanocellulose, and bamboo-based plastic composite materials. This invention achieves efficient, clean, and high-value utilization of all components of Arundo donax, forming a complete industrial chain.

Description

Technical Field

[0001] This invention relates to the field of high-value comprehensive utilization technology of biomass resources, and in particular to a method for graded utilization of all components of Phragmites australis guided by segmented fiber crushing. Background Technology

[0002] As a high-yielding and highly resilient energy plant (resistant to cold, drought, and salinity), Reed (Phragmites australis) boasts high biomass production and is rich in cellulose, hemicellulose, and lignin (collectively known as the "three elements"), as well as leaf flavonoids and other components with high development value, making it an ideal raw material for biomanufacturing and green chemistry. Currently, the industrial development of Reed as a raw material is still in its initial stage, mainly focusing on single or low-value utilization pathways such as physical methods for producing fuel pellets, gasification synthesis of green methanol or jet fuel, anaerobic fermentation for methane production, and traditional chemical methods for extracting crude fiber.

[0003] The existing technology mainly suffers from the following bottlenecks:

[0004] The industrial chain is fragmented and lacks a systematic approach: existing research and industrial practices mostly focus on a specific link in the supply chain of Phragmites australis (such as breeding, planting, or processing of a single product), and have not yet formed a systematic technical route and operational standards for the entire industrial chain, from targeted breeding and seedling cultivation, standardized planting, mechanized harvesting to the refined separation of all components and high-value derivatives. This results in poor coordination between links, making it difficult to achieve a large-scale and stable supply of industrial raw materials.

[0005] Incomplete utilization of components and serious waste of resources: Most existing processes fail to achieve the synergistic utilization of the entire Arundo donax plant (leaves and culms), especially the efficient, clean separation and deep conversion of high-value flavonoids in Arundo donax leaves and the "three elements" in the culms. There is a common situation of "using culms and discarding leaves" or "extensive utilization", which fails to achieve the highest value development goal of "fully utilizing" Arundo donax biomass.

[0006] Key separation technologies are immature, and their environmental and economic efficiency is poor: In core processes such as the separation of the three elements (cellulose, lignin, and flavonoids) and extraction of flavonoids from Arundo donax, traditional methods (such as strong acid-base chemical methods and high-temperature-high-pressure extraction) often suffer from low separation efficiency, low product purity, high solvent consumption, high energy consumption, and serious wastewater and waste residue pollution. In particular, there is still a lack of mature and reliable solutions for efficient and low-damage leaf and stalk separation technologies tailored to the characteristics of Arundo donax, as well as integrated technologies for the purification of hemicellulose sugar solutions, lignin, and flavonoids that are suitable for industrialization and environmental protection.

[0007] There is a lack of high-value product development pathways: Currently, the types of end products derived from Reed are limited and the added value is not high. The huge potential of Reed as a platform raw material for producing high-end bio-based materials (such as nanocellulose and high-performance polylactic acid), fine chemicals (such as high-purity lactide and lignin), and pharmaceutical and health product raw materials (such as high-purity flavonoids) has not been fully realized.

[0008] Therefore, developing an integrated process for the entire Reed rush industry chain that can span from breeding to end products, realize high-value utilization of all components, and integrate environmentally friendly and efficient separation and purification technologies is of urgent need and great significance for promoting the upgrading and development of the Reed rush industry and improving resource utilization efficiency and economic benefits. Summary of the Invention

[0009] The present invention aims to address the shortcomings of the prior art by providing a method for graded utilization of all components of Reed sphagnum moss by segmented crushing and fiber guidance.

[0010] To achieve the above objectives, this invention employs the following technical solution: a method for the graded utilization of all components of Reed rush through segmented crushing and fiber-guided processing. This method, through the collaborative design of front-end and back-end processes, systematically couples customized agronomic front-end processes, differentiated component separation paths, and a shared environmentally friendly purification platform to achieve the joint production of multiple series of high-value products from a single Reed rush raw material. The method includes the following steps:

[0011] S1. Customized production and supply of targeted raw materials: Reed raw materials adapted to the subsequent mechanized separation and crushing processes using front-end agronomic production. The Reed raw materials are Reed segments with a stem length of 15 cm.

[0012] S2. Differential separation and pretreatment of whole plant components: The leaves and stems of the reed segments obtained in step S1 were mechanically separated and then subjected to targeted pretreatment.

[0013] S21. Leaf component processing path: The separated Reed leaves are subjected to liquid-solid co-pulverization and alcohol solvent extraction to form an extract mixture containing flavonoids;

[0014] S22, Stem Component Processing Path: The separated leafless reed stems are sequentially subjected to high-pressure water jet transverse fixed-length cutting, longitudinal hydraulic crushing along the fiber, and high-pressure water jet fine crushing to obtain reed fiber powder with a specific fiber morphology.

[0015] S3. High-value conversion of components based on a shared purification platform:

[0016] S31, Leaf high-value conversion: The extraction mixture obtained in step S21 is sent to the first membrane integrated purification and solvent recovery system to simultaneously separate and produce high-purity arundinacea flavonoids and arundinacea leaf powder, and recover the alcohol solvent.

[0017] S32. Separation and Derivatization of the Three Elements in Bamboo: The bamboo fiber powder obtained in step S22 is subjected to steam explosion pretreatment, hemicellulose dissolution, and catalytic solvent separation of lignin and cellulose. During this process, the hemicellulose sugar solution and lignin separation solution are respectively introduced into the second membrane integrated purification and solvent recovery system for processing to separate and purify xylose / syrup and high-purity lignin, and recover the process solvent. The high-purity cellulose, xylose or syrup obtained are used as platform intermediates for further derivatization to prepare a variety of bio-based chemicals and bio-based materials, including lactide, polylactic acid resin, nanocellulose and bamboo-based plastic composite materials.

[0018] Specifically, the front-end agronomy in step S1 is a customized production system that integrates systems to ensure a long-term, stable, and uniform supply of raw materials. This system specifically includes the following sequentially connected links:

[0019] Targeted breeding and seedling cultivation: By screening polyploid genes of Phragmites australis to cultivate multi-fiber germplasm, then using culture medium to cultivate embryo seedlings, and then using greenhouse root division seedling cultivation and adaptability hardening seedlings in planting sites to obtain high-quality seedlings with consistent traits.

[0020] Standardized transplanting: The cultivated seedlings are transplanted in 2-meter-wide ridges with 0.6-meter intervals and three rows with gaps of 1020 plants each. Channels and trenches are left between the ridges for ventilation, mechanical operation, drainage, salt and alkali removal.

[0021] Cyclic management: Apply base fertilizer once a year after harvesting or before new shoots sprout; and adjust water supply according to annual rainfall to ensure water availability;

[0022] Customized harvesting: During the perennial growth period of Phyllostachys aurea, from November to February of the following year, mechanized equipment is used to harvest and pack the stems of Phyllostachys aurea at a uniform height, row by row, to obtain Phyllostachys aurea segments with a stem length of 15 cm.

[0023] Specifically, in step S2, the leaves and stems of the reed segments are mechanically separated. This is achieved through the following process: the reed segments are packaged and sent to the temporary warehouse of the primary processing base for dehydration pretreatment. Then, they are mechanically separated by a leaf and stem peeling machine, and then separated by air separation and drying. Finally, the separated reed leaves are sent to the reed leaf raw material storage warehouse, and the separated leafless reed stems are sent to the reed stem raw material storage warehouse, thus completing the raw material storage of reed leaves and leafless reed stems.

[0024] Specifically, in step S21, the flavonoid-containing extraction mixture is obtained through the following process:

[0025] S211. After purification and low-temperature drying, the leaves of Reed are fed together with an ethanol solution into a pulverizing device for liquid-solid co-pulverization to 80 mesh, and the flavonoids are initially dissolved during the pulverization process.

[0026] S212. Apply ultrasonic cyclic vibration at a frequency of 20-40 kHz and a power of 300-700 W to the obtained slurry to promote dissolution and enhance the dissolution of flavonoids, thereby obtaining an extract mixture containing flavonoids.

[0027] Specifically, in step S31, the first membrane integrated purification and solvent recovery system includes a horizontal screw centrifuge separation unit, a multi-stage membrane purification unit, a freeze-drying crystallization unit, and a solvent distillation recovery unit connected in sequence.

[0028] The horizontal spiral centrifuge unit performs millimeter-scale solid-liquid separation on the extraction mixture to obtain flavonoid extract and ethanol-containing solid residue;

[0029] The multi-stage membrane purification unit sequentially performs ultrafiltration to remove macromolecular impurities, nanofiltration to remove small molecule impurities, and nanofiltration dialysis to concentrate the flavonoid extract, thereby obtaining a high-purity flavonoid concentrate.

[0030] The freeze-drying crystallization unit converts high-purity flavonoid concentrate into high-purity reed flavonoid powder;

[0031] The solvent distillation and recovery unit distills the solid residue containing ethanol and the alcohol-containing waste liquid generated during the membrane purification process to recover ethanol for recycling, while also obtaining dried Reed Leaf powder.

[0032] Specifically, in step S22, the Reed Fiber Powder with a specific fibrous morphology is obtained through the following sequential physical crushing and processing steps:

[0033] S221, Oriented Stacking and Intelligent Segmentation: Leafless reed stems are oriented and stacked, and then cut to a fixed length using a high-pressure water jet cross-cutting device; the cutting device automatically adjusts the cutting length according to the identification result of stem nodes. When a stem node is identified, the cutting length is 5 cm; when no node is identified, the cutting length is 2 cm.

[0034] S222, longitudinal crushing along the fiber: The cut sections of Reed stalks are fed into a high-pressure water jet longitudinal crushing device and subjected to high-frequency oscillating hydraulic crushing along the fiber direction to dissociate them into fiber bundles;

[0035] S223. Fiber Refining and Crushing: The fiber bundles are further crushed by a high-pressure hydroentangling device to obtain fiber powder;

[0036] S224. Screening and post-processing: The fiber powder is screened by vibration to collect uniform fiber powder in the range of 20-60 mesh; then washed with water and dried by circulating air boiling at ≤60℃ to obtain the reed fiber powder for the separation of the three elements. The reed fiber powder is then stored in the intermediate reed fiber powder storage silo.

[0037] Specifically, in step S32, the steam explosion pretreatment and hemicellulose dissolution are achieved through the following steps:

[0038] S321, Steam explosion treatment: Place the reed fiber powder in a steam explosion reactor and maintain it at a saturated steam pressure of 1.6-2.0 MPa and a temperature of 190-210°C for 5-15 minutes, then instantly depressurize and explode to obtain the pretreated brownish-brown material.

[0039] S322, Hemicellulose dissolution: Treat the brown material with hot water or a 2% NaOH dilute alkaline solution at 60-80℃ for 1-2 hours to fully dissolve the hemicellulose component;

[0040] S323, Preliminary solid-liquid separation: The material after step S322 is subjected to millimeter-level solid-liquid separation to obtain hemicellulose sugar solution and cellulose-lignin solid phase residue.

[0041] The catalytic solvent separation of lignin and cellulose is achieved through the following steps:

[0042] S324. Catalytic reaction: The solid residue obtained in step S323 is mixed with an ethanol-water solution with a volume ratio of 1:1, and a catalytic amount of sulfuric acid is added. The mixture is reacted at 160-180℃ for 1-3 hours.

[0043] S325, Primary separation: The material after the reaction in step S324 is subjected to millimeter-level solid-liquid separation to obtain a cellulose-rich solid phase and a lignin-rich liquid phase.

[0044] Specifically, the second membrane integrated purification and solvent recovery system includes a first membrane purification branch, a second membrane purification branch, and a common solvent recovery unit arranged in parallel.

[0045] The first membrane purification branch is used to process hemicellulose sugar solution and consists of the following components connected in sequence: a microfiltration or ultrafiltration membrane module for retaining residual solid particles, a first nanofiltration membrane module for separating oligosaccharides, a second nanofiltration membrane module for desalting monosaccharides, and an ultrafiltration membrane module for purifying the sugar solution; after processing by this branch, xylose or syrup products are obtained.

[0046] The second membrane purification branch is used to process the lignin-rich liquid phase and consists of the following components connected in sequence: a microfiltration or ultrafiltration membrane module for filtering out trace fibers and colloids, a nanofiltration membrane module for concentrating lignin and dialysis to recover sulfuric acid, and a distillation unit for separating the product from the lignin concentrate; after processing by this branch, a high-purity lignin product is obtained and ethanol is recovered.

[0047] A shared solvent recovery unit is used to receive and process solvent-containing streams generated from each branch to recover and recycle ethanol, water, and sulfuric acid from the process.

[0048] Specifically, the cellulose-rich solid phase separated in step S325 is high-purity cellulose, which is subjected to high-value conversion through at least one of the following methods:

[0049] a. Fiber grading: The fiber is dispersed in water and mechanically decomposed and sieved to obtain long fibers with a mesh size greater than 100, medium fibers with a mesh size of 100 to 200, and short fibers with a mesh size less than 200.

[0050] b. Nanofiber preparation: Short fiber slurry was modified by carboxymethylation and then homogenized under high pressure to prepare microfibrillated cellulose and fibrous nanofibers;

[0051] c. Nanocrystal preparation: Cellulose nanocrystals are prepared by acid hydrolysis of microfibrillated cellulose and fibrous nanofibers.

[0052] In particular, xylose or syrup products, as fermentation raw materials, are used to derive polylactic acid (PLA) series products through the following pathways:

[0053] Fermentation and purification: After detoxification, decolorization and concentration adjustment, it is used as a fermentation raw material, and high-purity lactic acid is obtained through microbial fermentation and purification;

[0054] L-lactide synthesis: High-purity lactic acid is purified by dehydration condensation, depolymerization cyclization and distillation to obtain L-lactide and D-lactide products with high optical purity.

[0055] Polymerization Derivatization: Polylactic acid products are prepared using high optical purity L-lactide and D-lactide as raw materials through at least one of the following methods:

[0056] copolymerization reaction to prepare polyracemic lactic acid;

[0057] Stereocomposite reaction to prepare stereocomposite polylactic acid;

[0058] High molecular weight polylactic acid bioresin was prepared by ring-opening polymerization using L-lactide or a mixture of L-lactide and D-lactide as monomers.

[0059] Specifically, high molecular weight polylactic acid bioresin and high purity cellulose were melt-blended and granulated at a mass ratio of 6:4 to prepare bamboo-based plastic composite material particles.

[0060] The beneficial effects of this invention are:

[0061] 1. Achieved systematic integration and value maximization of the entire Reed rush industry chain: This invention proposes and constructs a complete and replicable technical system from polyploid gene screening and breeding, standardized intelligent planting, customized harvesting to full-component graded utilization. By systematically coupling customized agronomic front-end, differentiated leaf and stalk separation paths, and a shared environmentally friendly purification platform, a stable and uniform supply of raw materials is ensured, and the directional and efficient conversion of various components of Reed rush leaves and stalks is achieved. This truly realizes the "complete utilization" of Reed rush resources, and can simultaneously produce up to fifteen high-value-added products, greatly improving the economic benefits of the entire industry chain.

[0062] 2. Provides efficient and clean solutions for leaf-stem separation and the separation of cellulose, hemicellulose, and lignin: Through optimized mechanical peeling and air-separation drying processes, efficient and low-damage separation of reed leaves and stems is achieved, laying the foundation for subsequent independent high-value processing. The use of a combination of high-pressure water jet intelligent cutting and crushing technology to process the stems allows for automatic process adjustments based on stem nodes, achieving low-damage and high-efficiency fiber dissociation, which is beneficial for subsequent separation of the three components. A combined process of steam explosion pretreatment, mild alkaline leaching, and catalytic solvent separation achieves efficient and relatively clean separation of cellulose, hemicellulose, and lignin, providing high-purity raw materials for the deep processing of each component.

[0063] 3. A highly efficient and environmentally friendly shared purification and resource recycling platform was constructed: First and second purification systems based on multi-stage membrane integration technology (microfiltration, ultrafiltration, and nanofiltration) were designed for flavonoid extract, hemicellulose syrup, and lignin separation liquid, respectively. This platform design achieves high-precision separation and purification of different material flows, replacing traditional high-energy-consuming and high-polluting separation methods, resulting in high product purity and yield. Both systems integrate solvent recovery units (distillation), enabling efficient recovery of ethanol, water, and catalyst (sulfuric acid) and achieving recycling, significantly reducing production costs and organic solvent emissions, embodying a green and environmentally friendly process concept.

[0064] 4. A diversified path for high-value product development has been established: High-purity cellulose is used to derive a series of high-end bio-based materials, including long / medium / short fibers, microfibrillated cellulose (MFC), cellulose nanofibers (CNF), and cellulose nanocrystals (CNC), through grading, modification, and nano-sizing. Purified xylose / syrup is successfully used in a combination of bio-fermentation and chemical synthesis to derive high-value bio-based chemicals and biodegradable materials, such as high-optical-purity L / D-lactide, high-molecular-weight polylactic acid (PLA), polyracemic lactic acid (PDLLA), and stereocomposite polylactic acid (sc-PLA). By compounding self-produced PLA resin with high-purity cellulose, "bamboo-based plastic" composite material particles have been successfully prepared, providing new high-performance raw materials for bio-based biodegradable plastics and achieving a closed-loop and extended industrial chain. Attached Figure Description

[0065] Figure 1 This is a flowchart illustrating the overall process for the graded utilization of all components of Reed sphagnum moss according to the present invention.

[0066] Figure 2 This is a customized agronomic front-end flowchart for the present invention;

[0067] Figure 3 This is a flowchart of the leaf component treatment and flavonoid purification and recovery process of the present invention;

[0068] Figure 4 This is a flowchart of the physical crushing process of the straw components of the present invention;

[0069] Figure 5 This is a flowchart of the three-element separation and membrane integrated purification process of the present invention;

[0070] Figure 6 This is a composite diagram of the downstream derivative paths and end products of the two platform intermediates of the present invention;

[0071] The following will describe in detail, with reference to the accompanying drawings, embodiments of the present invention. Detailed Implementation

[0072] The present invention will be further described below with reference to embodiments:

[0073] like Figures 1-6 As shown, a method for the graded utilization of all components of Reed rush through segmented crushing and fiber-guided processing is presented. This method, through the collaborative design of front-end and back-end processes, systematically couples customized agronomic front-end processes, differentiated component separation paths, and a shared environmentally friendly purification platform to achieve the joint production of multiple series of high-value products from a single Reed rush raw material. The method includes the following steps:

[0074] S1. Customized production and supply of targeted raw materials: Reed raw materials adapted to the subsequent mechanized separation and crushing processes using front-end agronomic production. The Reed raw materials are Reed segments with a stem length of 15 cm.

[0075] S2. Differential separation and pretreatment of whole plant components: The leaves and stems of the reed segments obtained in step S1 were mechanically separated and then subjected to targeted pretreatment.

[0076] S21. Leaf component processing path: The separated Reed leaves are subjected to liquid-solid co-pulverization and alcohol solvent extraction to form an extract mixture containing flavonoids;

[0077] S22, Stem Component Processing Path: The separated leafless reed stems are sequentially subjected to high-pressure water jet transverse fixed-length cutting, longitudinal hydraulic crushing along the fiber, and high-pressure water jet fine crushing to obtain reed fiber powder with a specific fiber morphology.

[0078] S3. High-value conversion of components based on a shared purification platform:

[0079] S31, Leaf high-value conversion: The extraction mixture obtained in step S21 is sent to the first membrane integrated purification and solvent recovery system to simultaneously separate and produce high-purity arundinacea flavonoids and arundinacea leaf powder, and recover the alcohol solvent.

[0080] S32. Separation and Derivatization of the Three Elements in Bamboo: The bamboo fiber powder obtained in step S22 is subjected to steam explosion pretreatment, hemicellulose dissolution, and catalytic solvent separation of lignin and cellulose. During this process, the hemicellulose sugar solution and lignin separation solution are respectively introduced into the second membrane integrated purification and solvent recovery system for processing to separate and purify xylose / syrup and high-purity lignin, and recover the process solvent. The high-purity cellulose, xylose or syrup obtained are used as platform intermediates for further derivatization to prepare a variety of bio-based chemicals and bio-based materials, including lactide, polylactic acid resin, nanocellulose and bamboo-based plastic composite materials.

[0081] This invention systematically couples the previously fragmented agronomic, separation, and processing stages, forming a complete industrial chain with interconnected ends and a closed-loop material supply. Through the design of "differentiated separation" and "shared platform purification," it achieves the synchronous, efficient, and high-value utilization of all components (leaves and culms) of Phragmites australis, solving the core pain points of serious resource waste, single product, and low added value in traditional industries, and truly achieving the highest goal of "fully utilizing" resources.

[0082] In step S1, the front-end agronomy is a customized production system that integrates systems to ensure a long-term, stable, and uniform supply of raw materials. This system specifically includes the following sequentially connected links:

[0083] Targeted breeding and seedling cultivation: By screening polyploid genes of Phragmites australis to cultivate multi-fiber germplasm, then using culture medium to cultivate embryo seedlings (in a closed plant workshop), and then dividing the roots for seedling cultivation in greenhouses (warm greenhouses in the north and cool greenhouses in the south), and selecting seedlings through adaptability hardening in the planting area to obtain high-quality seedlings with consistent traits.

[0084] Standardized transplanting: Using intelligent or mechanized transplanting technology, the cultivated seedlings are transplanted in 2-meter-wide ridges with 0.6-meter intervals and 1020 plants per 3 rows with gaps between them. Channels and trenches are left between the ridges for ventilation, mechanical operation, drainage, salt and alkali removal.

[0085] Cyclic management: Apply base fertilizer once a year after harvesting or before new shoots sprout; and adjust water supply according to annual rainfall to ensure water supply; no watering is needed if the annual rainfall is not less than 500 mm, and watering is needed if the rainfall is less than 500 mm, with a total of not less than 400 cubic meters per acre, watered once every two months.

[0086] Customized harvesting: During the perennial growth period of Phragmites australis (a single planting of Phragmites australis can continue for 15 to 20 years of harvesting), from November to February of the following year, mechanized equipment is used to harvest and pack the Phragmites australis stems at a uniform height, row by row, to obtain Phragmites australis segments with a stem length of 15 cm.

[0087] This agronomic system ensures a high-quality foundation for raw materials through "gene screening-tissue culture seedlings"; the standardized "three-row wide ridge" planting model improves land utilization and yield while ensuring good ventilation and mechanized operation conditions; the simplified management strategy of "one base fertilizer and watering as needed" greatly reduces water and fertilizer input and labor costs while ensuring yield; and the customized solution of "uniform specifications and winter harvesting" ensures that the physical form (length, moisture content) and chemical composition (fiber content) of the raw materials are highly uniform, perfectly meeting the stringent requirements of subsequent industrial processing for raw material consistency, which is the primary prerequisite for achieving large-scale, continuous production.

[0088] In step S2, the leaves and stems of the Reed Stalks are mechanically separated. This is achieved through the following process: the Reed Stalks are packaged and sent to a temporary warehouse at the primary processing base for dehydration pretreatment (such as sun-drying). Then, they are mechanically separated using a leaf-stem peeling machine, followed by air-separation drying (completing separation and dehydration). Finally, the separated Reed Stalks are sent to the Reed Stalk raw material storage warehouse, and the separated leafless Reed Stalks are sent to the Reed Stalk raw material storage warehouse, thus completing the raw material storage of Reed Stalks and leafless Reed Stalks. Reed Stalks are supplied year-round for ultrafine powder extraction to produce high-purity flavonoids and Reed Stalk dry powder. Reed Stalks are supplied year-round for the separation of cellulose, hemicellulose, and lignin, and further separation and decomposition to manufacture various high-end environmentally friendly industrial raw materials.

[0089] This step employs a combined leaf-stem separation process of "mechanical peeling + air-separation drying," replacing traditional manual or simple mechanical separation methods. This process is highly efficient, has a large processing capacity, and achieves thorough and clean separation of leaves and stems with minimal fiber damage. The separated leaves have high integrity, which is beneficial for the effective extraction of flavonoids; the stems are free of leaf impurities, creating conditions for the subsequent high-purity separation of the three essential elements (flavonoids, nutrient, and stem).

[0090] In step S21, the flavonoid-containing extraction mixture is obtained through the following process:

[0091] S211. After purification and low-temperature drying, the leaves of Reed are fed together with an ethanol solution (68% concentration) into a pulverizing device for liquid-solid synergistic pulverization (liquid-liquid-blade composite steel blade synergistic pulverization) to 80 mesh, and the flavonoids are initially dissolved during the pulverization process.

[0092] S212. Apply ultrasonic cyclic vibration at a frequency of 20-40 kHz and a power of 300-700 W to the obtained slurry to promote dissolution and enhance the dissolution of flavonoids, thereby obtaining an extract mixture containing flavonoids.

[0093] This step employs a combination of "liquid-solid synergistic pulverization" and "ultrasonic enhanced extraction." The ethanol solvent comes into full contact with the material immediately upon pulverization and begins to dissolve flavonoids, achieving synchronization between extraction and pulverization, significantly shortening the extraction time. Subsequent ultrasonic treatment utilizes its cavitation, mechanical, and thermal effects to further disrupt plant cell walls, greatly promoting the dissolution rate and extraction yield of flavonoids. Compared to traditional single soaking or hot reflux extraction, this method offers significant advantages such as high efficiency, short extraction time, relatively low solvent consumption, and minimal damage to active ingredients.

[0094] In step S31, the first membrane integrated purification and solvent recovery system includes a horizontal screw centrifuge separation unit, a multi-stage membrane purification unit, a freeze-drying crystallization unit, and a solvent distillation recovery unit connected in sequence.

[0095] The horizontal spiral centrifuge unit performs millimeter-scale solid-liquid separation on the extraction mixture to obtain flavonoid extract and ethanol-containing solid residue;

[0096] The multi-stage membrane purification unit sequentially performs ultrafiltration to remove macromolecular impurities, nanofiltration to remove small molecule impurities, and nanofiltration dialysis to concentrate the flavonoid extract, thereby obtaining a high-purity flavonoid concentrate.

[0097] The freeze-drying crystallization unit converts high-purity flavonoid concentrate into high-purity reed flavonoid powder;

[0098] The solvent distillation and recovery unit distills the solid residue containing ethanol and the alcohol-containing waste liquid generated during the membrane purification process to recover ethanol for recycling, and at the same time obtains Reed Leaf powder (which requires cold chain storage and transportation to ensure activity).

[0099] This integrated system is the core of flavonoid high-value utilization and resource recovery. Its advantages include: High-efficiency integration and purification: Through a process of "centrifugation-multi-stage membrane separation-lyophilization," continuous and efficient purification of flavonoids from crude extract to high-purity powder is achieved. The application of membrane technology replaces expensive and time-consuming steps such as traditional chromatography, resulting in high product purity and yield. Resource closed-loop and zero waste discharge: The system's embedded solvent recovery unit recovers and recycles almost all ethanol from solid residues and membrane filtration waste liquid, significantly reducing solvent costs and avoiding pollution from organic waste liquids. Simultaneously, the solid residue is converted into valuable Reed Leaf powder, achieving complete material utilization.

[0100] In step S22, the Reed Fiber Powder with a specific fiber morphology is obtained through the following sequential physical crushing and processing steps:

[0101] S221, Oriented Stacking and Intelligent Segmentation: Leafless reed stems are oriented and stacked, and then cut to a fixed length (2-5 cm) using a high-pressure water jet cross-cutting device; the cutting device automatically adjusts the cutting length according to the identification result of stem nodes. When a stem node is identified, the cutting length is 5 cm; when no node is identified, the cutting length is 2 cm.

[0102] S222, longitudinal crushing along the fiber: The cut sections of Reed stalks are fed into a high-pressure water jet longitudinal crushing device and subjected to high-frequency oscillating hydraulic crushing along the fiber direction to dissociate them into fiber bundles;

[0103] S223. Fiber Refining and Crushing: The fiber bundles are further crushed by a high-pressure hydroentangling device to obtain fiber powder;

[0104] S224. Screening and post-processing: The fiber powder is screened by vibration to collect uniform fiber powder in the range of 20-60 mesh; then washed with water and dried by circulating air boiling at ≤60℃ to obtain the reed fiber powder for the separation of the three elements. The reed fiber powder is then stored in the intermediate reed fiber powder storage silo.

[0105] This step employs a purely physical "high-pressure water jet combined crushing" technology. Its advantages include: low damage and high efficiency: The "cold" cutting and crushing method of the water jet avoids damage to the fiber structure caused by frictional heat from mechanical blades, maximizing the preservation of the fiber's natural length and strength, thus ensuring the subsequent production of high-quality cellulose products. Intelligent and homogenized operation: Intelligent identification of nodules and adjustment of cutting length solves the problem of uneven crushing caused by varying nodule hardness, ensuring high uniformity of the subsequent fiber powder particle size (20-60 mesh). This is a key prerequisite for achieving stable and efficient separation of the three elements (cellulose, fiber, and carbon).

[0106] In step S32, the steam explosion pretreatment and hemicellulose dissolution are specifically achieved through the following steps:

[0107] S321, Steam explosion treatment: Place the reed fiber powder in a steam explosion reactor and maintain it at a saturated steam pressure of 1.6-2.0 MPa and a temperature of 190-210°C for 5-15 minutes, then instantly depressurize and explode to obtain the pretreated brownish-brown material.

[0108] S322, Hemicellulose dissolution: Treat the brown material with hot water or a 2% NaOH dilute alkaline solution at 60-80℃ for 1-2 hours to fully dissolve the hemicellulose component;

[0109] S323, Preliminary solid-liquid separation: The material after step S322 is subjected to millimeter-level solid-liquid separation (horizontal screw separator) to separate hemicellulose sugar solution and cellulose-lignin solid phase residue.

[0110] The catalytic solvent separation of lignin and cellulose is achieved through the following steps:

[0111] S324. Catalytic reaction: The solid residue obtained in step S323 is mixed with an ethanol-water solution with a volume ratio of 1:1, and a catalytic amount of sulfuric acid is added. The mixture is reacted at 160-180℃ for 1-3 hours.

[0112] S325, Primary separation: The material after the reaction in step S324 is subjected to millimeter-level solid-liquid separation (horizontal screw separator) to obtain a solid phase rich in cellulose and a liquid phase rich in lignin.

[0113] This three-element separation process combines steam explosion, mild alkali dissolution, and catalytic solvent method, offering significant advantages: Highly efficient dissociation: Steam explosion, through the instantaneous release of high-temperature, high-pressure steam, powerfully disrupts the lignin-carbohydrate complex structure (LCC bonds), significantly improving the efficiency of subsequent component separation. Mild conditions and high selectivity: Using a low-concentration alkali solution at a lower temperature dissolves hemicellulose, avoiding the severe degradation of cellulose by strong alkali at high temperatures; the subsequent ethanol-water catalytic system efficiently breaks the chemical bonds between lignin and cellulose, and while dissolving lignin, separates cellulose in a solid phase with high yield and high purity. Compared to traditional acid or high-strength alkali methods, this route provides better separation results, less cellulose damage, and higher product purity.

[0114] The second membrane integrated purification and solvent recovery system includes a first membrane purification branch, a second membrane purification branch, and a common solvent recovery unit arranged in parallel.

[0115] The first membrane purification branch is used to process hemicellulose sugar solution and consists of the following components connected in sequence: a microfiltration or ultrafiltration membrane module for retaining residual solid particles, a first nanofiltration membrane module for separating oligosaccharides, a second nanofiltration membrane module for desalting monosaccharides, and an ultrafiltration membrane module for purifying the sugar solution; after processing by this branch, xylose or syrup products are obtained.

[0116] The second membrane purification branch is used to process the lignin-rich liquid phase and consists of the following components connected in sequence: a microfiltration or ultrafiltration membrane module for filtering out trace fibers and colloids, a nanofiltration membrane module for concentrating lignin and dialysis to recover sulfuric acid, and a distillation unit for separating the product from the lignin concentrate; after processing by this branch, a high-purity lignin product is obtained and ethanol is recovered.

[0117] A shared solvent recovery unit is used to receive and process solvent-containing streams generated from each branch to recover and recycle ethanol, water, and sulfuric acid from the process.

[0118] The second membrane integration system in this step is one of the core technology platforms of this invention. Its advantages are: Precise fractionation and purification: Two parallel but customized membrane separation and purification routes were designed to address the different physicochemical properties of hemicellulose sugar solution and lignin solution. Through the combination of microfiltration, ultrafiltration, and nanofiltration membranes and precise molecular weight cutoff control, the fine separation and desalination of oligosaccharides and monosaccharides in the sugar solution were achieved, as well as the high-concentration of lignin and the efficient dialysis recovery of the catalyst (sulfuric acid). The purity and quality of the product meet the standards for high-end applications. Efficient resource recycling: The shared solvent recovery unit realizes the internal circulation of key media such as ethanol, water, and sulfuric acid, constructing a closed loop for clean production and reducing pollutant emissions and raw material consumption from the source of engineering.

[0119] The cellulose-rich solid phase separated in step S325 is high-purity cellulose, which is subjected to high-value conversion through at least one of the following methods:

[0120] a. Fiber grading: The fiber is dispersed in water and mechanically decomposed and sieved to obtain long fibers with a mesh size greater than 100, medium fibers with a mesh size of 100 to 200, and short fibers with a mesh size less than 200.

[0121] b. Nanofiber preparation: Short fiber slurry is modified by carboxymethylation and then homogenized under high pressure to prepare microfibrillated cellulose and fibrous nanofibers; specifically, after carboxymethylation, negative charges are introduced on the surface of the short fibers, and the carboxymethylated fiber slurry is sprayed and impacted by a high-pressure homogenizer under extremely high pressure (such as 500-1000 bar) to microfibrilize the fibers and obtain microfibrillated cellulose (MFC) and fibrous nanofibers (CNF) products;

[0122] c. Nanocrystal preparation: Cellulose nanocrystals are prepared by acid hydrolysis of microfibrillated cellulose and fibrous nanofibers; specifically: microfibrillated cellulose (MFC) and fibrous nanofibers (CNF) are ground and sheared by a nano-grinding machine and exfoliated by high-intensity ultrasonic cavitation to produce nanofibers, and pure cellulose is hydrolyzed with concentrated sulfuric acid (64% WT) at 45°C for 30-60 minutes to prepare cellulose nanocrystals (CNC) products.

[0123] This step enables the full-spectrum, high-value development of cellulose from the macro to the nanoscale. Its advantages include: product tiering: fiber products of different lengths can be obtained through simple mechanical sieving, meeting the needs of various industrial fields such as papermaking and composite material reinforcement, resulting in broad market adaptability. Mature nanotechnology route: the adopted "carboxymethylation pretreatment-high-pressure homogenization" is a classic and efficient method for preparing MFC / CNF, while "acid hydrolysis" is the standard method for preparing CNC. Based on the high-purity cellulose raw materials obtained in the preceding steps, this step can stably prepare high-performance nanocellulose products with extremely high added value, providing core raw materials for entering the high-end bio-based materials market.

[0124] Xylose or syrup products are used as fermentation raw materials to derive polylactic acid (PLA) series products through the following pathways:

[0125] Fermentation and purification: After detoxification, decolorization and concentration adjustment, it is used as a fermentation raw material. High-purity lactic acid is obtained through microbial fermentation and purification. Specifically, xylose / syrup products are detoxified, decolorized and the concentration is adjusted to a stable mixture of C5 and C6 sugars. The fermentation raw material is fermented in batches with special mixed bacteria, and then high-purity lactic acid is produced by esterification / molecular distillation.

[0126] Lactide synthesis: High-purity lactic acid is purified by dehydration condensation, depolymerization cyclization, and distillation to obtain high-optical-purity L-lactide and D-lactide products; specifically: lactic acid undergoes dehydration condensation reaction to generate low-molecular-weight polylactic acid prepolymer, which is then heated to depolymerize and generate cyclic dimer lactide, which is then separated and purified by distillation to obtain high-optical-purity L-lactide and D-lactide products.

[0127] Polymerization Derivatization: Polylactic acid products are prepared using high optical purity L-lactide and D-lactide as raw materials through at least one of the following methods:

[0128] Copolymerization reaction was used to prepare polyracemic lactic acid (PDLLA).

[0129] Stereocomposite reaction to prepare stereocomposite polylactic acid (sc-PLA).

[0130] High molecular weight polylactic acid bioresin (PLA) is prepared by ring-opening polymerization of L-lactide or a mixture of L-lactide and D-lactide as monomers in the presence of a catalyst (such as stannous octoate).

[0131] This step successfully bridges the gap between biomass sugars derived from Arundo donax and mature bio-fermentation and chemical synthesis processes, transforming them into polylactic acid (PLA) and its key upstream monomers—a bio-based biodegradable material in high demand in the current market. Its advantages lie in: a complete and mature pathway: from sugar fermentation to lactic acid, and then to lactide purification and polymerization, each step utilizes industry-proven and reliable technologies, ensuring conversion efficiency and product quality from biomass to polymer materials. High-end products: In addition to producing general-purpose PLA resin, it can also produce high-performance sc-PLA and high-purity L / D-lactide monomers through stereochemical configuration control, penetrating higher-profit niche markets such as medical and high-end packaging, significantly raising the added value ceiling of the Arundo donax industry chain.

[0132] High molecular weight polylactic acid bioresin and high purity cellulose were melt-blended and granulated at a mass ratio of 6:4 to prepare bamboo-based plastic composite material particles.

[0133] This step achieves a closed-loop industrial chain and maximizes value. Its advantages include: performance optimization and cost control: Cellulose, as a natural reinforcing agent, effectively improves the mechanical strength, heat resistance, and dimensional stability of PLA, while partially replacing the more expensive PLA resin, thus reducing the cost of composite materials. Creating distinctive end products: The resulting "bamboo-based plastic" granules combine bio-based, biodegradable, and reinforcing modification characteristics, making them a novel environmentally friendly material with distinctive features and market competitiveness. They can be directly used in injection molding, extrusion, and other processing, providing a high-value export with clear market acceptance for the entire bamboo reed industrial chain.

[0134] This invention is the first to construct and validate a complete and replicable system for the high-value utilization of the entire Reed rush industry chain. This method achieves end-to-end integration and optimization from gene selection to end-materials by deeply coupling three major modules: customized agronomic front-end, differentiated component separation pathway, and shared membrane integrated purification platform.

[0135] This breaks the limitation of the past disconnect between breeding, planting and processing in the utilization of reed bamboo. By producing raw materials (15 cm reed bamboo segments) with traits and specifications highly adapted to subsequent industrial processing through the front-end agronomy, it ensures the stable, efficient and large-scale operation of the entire industrial chain from the source.

[0136] Targeting the characteristics of Reed Leaf and Stem components, this study innovatively combines multiple sets of efficient and low-damage separation technologies, including "liquid-solid synergistic pulverization-ultrasonic enhanced extraction" and "high-pressure water jet intelligent crushing-steam explosion pretreatment-catalytic solvent separation." It also pioneered the use of two "multi-stage membrane integrated purification and solvent recovery systems" capable of processing different materials as a shared platform, achieving high-purity extraction of flavonoids, hemicellulose sugars, and lignin, as well as closed-loop solvent recycling. This significantly reduces energy consumption and environmental impact while improving product quality.

[0137] Using the separated high-purity cellulose and xylose / syrup as core platform intermediates, a full-spectrum, high-value-added product tree has been developed, encompassing fibers of different specifications, various nanocelluloses, high optical purity lactide, a series of polylactic acid resins, and even "bamboo-based plastic" composite materials. This not only achieves the complete utilization of reed biomass but also elevates the value of the industrial chain from traditional low-end fuels to the field of high-end bio-based materials and chemicals.

[0138] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0139] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0140] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0141] The present invention has been described above by way of example. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any improvements made by adopting the inventive concept and technical solution of the present invention, or direct application to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A method for graded utilization of all components of Reed sphagnum moss using segmented, fiber-guided crushing, characterized in that, This method, through the collaborative design of front-end and back-end processes, systematically couples customized agronomic front-end processes, differentiated component separation pathways, and a shared environmentally friendly purification platform to achieve the joint production of multiple series of high-value products from a single Reed rush raw material. The method includes the following steps: S1. Customized production and supply of targeted raw materials: Reed raw materials adapted to the subsequent mechanized separation and crushing processes using front-end agronomic production. The Reed raw materials are Reed segments with a stem length of 15 cm. S2. Differential separation and pretreatment of whole plant components: The leaves and stems of the reed segments obtained in step S1 were mechanically separated and then subjected to targeted pretreatment. S21. Leaf component processing path: The separated Reed leaves are subjected to liquid-solid co-pulverization and alcohol solvent extraction to form an extract mixture containing flavonoids; S22, Stem Component Processing Path: The separated leafless reed stems are sequentially subjected to high-pressure water jet transverse fixed-length cutting, longitudinal hydraulic crushing along the fiber, and high-pressure water jet fine crushing to obtain reed fiber powder with a specific fiber morphology. S3. High-value conversion of components based on a shared purification platform: S31, Leaf high-value conversion: The extraction mixture obtained in step S21 is sent to the first membrane integrated purification and solvent recovery system to simultaneously separate and produce high-purity arundinacea flavonoids and arundinacea leaf powder, and recover the alcohol solvent. S32. Separation and Derivatization of the Three Elements in Bamboo: The bamboo fiber powder obtained in step S22 is subjected to steam explosion pretreatment, hemicellulose dissolution, and catalytic solvent separation of lignin and cellulose. During this process, the hemicellulose sugar solution and lignin separation solution are respectively introduced into the second membrane integrated purification and solvent recovery system for processing to separate and purify xylose / syrup and high-purity lignin, and recover the process solvent. The high-purity cellulose, xylose or syrup obtained are used as platform intermediates for further derivatization to prepare a variety of bio-based chemicals and bio-based materials, including lactide, polylactic acid resin, nanocellulose and bamboo-based plastic composite materials.

2. The method for graded utilization of all components of Reed sphagnum moss using segmented, fiber-guided crushing according to claim 1, characterized in that, In step S1, the front-end agronomy is a customized production system that integrates systems to ensure a long-term, stable, and uniform supply of raw materials. This system specifically includes the following sequentially connected links: Targeted breeding and seedling cultivation: By screening polyploid genes of Phragmites australis to cultivate multi-fiber germplasm, then using culture medium to cultivate embryo seedlings, and then using greenhouse root division seedling cultivation and adaptability hardening seedlings in planting sites to obtain high-quality seedlings with consistent traits. Standardized transplanting: The cultivated seedlings are transplanted in 2-meter-wide ridges with 0.6-meter intervals and three rows with gaps of 1020 plants each. Channels and trenches are left between the ridges for ventilation, mechanical operation, drainage, salt and alkali removal. Cyclic management: Apply base fertilizer once a year after harvesting or before new shoots sprout; and adjust water supply according to annual rainfall to ensure water availability; Customized harvesting: During the perennial growth period of Phyllostachys aurea, from November to February of the following year, mechanized equipment is used to harvest and pack the stems of Phyllostachys aurea at a uniform height, row by row, to obtain Phyllostachys aurea segments with a stem length of 15 cm.

3. The method for graded utilization of all components of Reed sphagnum moss using segmented, fiber-guided crushing according to claim 1, characterized in that, In step S21, the flavonoid-containing extraction mixture is obtained through the following process: S211. After purification and low-temperature drying, the leaves of Reed are fed together with an ethanol solution into a pulverizing device for liquid-solid co-pulverization to 80 mesh, and the flavonoids are initially dissolved during the pulverization process. S212. Apply ultrasonic cyclic vibration at a frequency of 20-40 kHz and a power of 300-700 W to the obtained slurry to promote dissolution and enhance the dissolution of flavonoids, thereby obtaining an extract mixture containing flavonoids.

4. The method for graded utilization of all components of Reed sphagnum moss using segmented, fiber-guided crushing according to claim 3, characterized in that, In step S31, the first membrane integrated purification and solvent recovery system includes a horizontal screw centrifuge separation unit, a multi-stage membrane purification unit, a freeze-drying crystallization unit, and a solvent distillation recovery unit connected in sequence. The horizontal spiral centrifuge unit performs millimeter-scale solid-liquid separation on the extraction mixture to obtain flavonoid extract and ethanol-containing solid residue; The multi-stage membrane purification unit sequentially performs ultrafiltration to remove macromolecular impurities, nanofiltration to remove small molecule impurities, and nanofiltration dialysis to concentrate the flavonoid extract, thereby obtaining a high-purity flavonoid concentrate. The freeze-drying crystallization unit converts high-purity flavonoid concentrate into high-purity reed flavonoid powder; The solvent distillation and recovery unit distills the solid residue containing ethanol and the alcohol-containing waste liquid generated during the membrane purification process to recover ethanol for recycling, while also obtaining dried Reed Leaf powder.

5. The method for graded utilization of all components of Reed sphagnum moss using segmented, fiber-guided crushing according to claim 1, characterized in that, In step S22, the Reed Fiber Powder with a specific fiber morphology is obtained through the following sequential physical crushing and processing steps: S221, Oriented Stacking and Intelligent Segmentation: Leafless reed stems are oriented and stacked, and then cut to a fixed length using a high-pressure water jet cross-cutting device; the cutting device automatically adjusts the cutting length according to the identification result of stem nodes. When a stem node is identified, the cutting length is 5 cm; when no node is identified, the cutting length is 2 cm. S222, longitudinal crushing along the fiber: The cut sections of Reed stalks are fed into a high-pressure water jet longitudinal crushing device and subjected to high-frequency oscillating hydraulic crushing along the fiber direction to dissociate them into fiber bundles; S223. Fiber Refining and Crushing: The fiber bundles are further crushed by a high-pressure hydroentangling device to obtain fiber powder; S224. Screening and post-processing: The fiber powder is screened by vibration to collect uniform fiber powder in the range of 20-60 mesh; then washed with water and dried by circulating air boiling at ≤60℃ to obtain the reed fiber powder for the separation of the three elements. The reed fiber powder is then stored in the intermediate reed fiber powder storage silo.

6. The method for graded utilization of all components of Reed sphagnum moss using segmented, fiber-guided crushing according to claim 5, characterized in that, In step S32, the steam explosion pretreatment and hemicellulose dissolution are specifically achieved through the following steps: S321, Steam explosion treatment: Place the reed fiber powder in a steam explosion reactor and maintain it at a saturated steam pressure of 1.6-2.0 MPa and a temperature of 190-210°C for 5-15 minutes, then instantly depressurize and explode to obtain the pretreated brownish-brown material. S322, Hemicellulose dissolution: Treat the brown material with hot water or a 2% NaOH dilute alkaline solution at 60-80℃ for 1-2 hours to fully dissolve the hemicellulose component; S323, Preliminary solid-liquid separation: The material after step S322 is subjected to millimeter-level solid-liquid separation to obtain hemicellulose sugar solution and cellulose-lignin solid phase residue. The catalytic solvent separation of lignin and cellulose is achieved through the following steps: S324. Catalytic reaction: The solid residue obtained in step S323 is mixed with an ethanol-water solution with a volume ratio of 1:1, and a catalytic amount of sulfuric acid is added. The mixture is reacted at 160-180℃ for 1-3 hours. S325, Primary separation: The material after the reaction in step S324 is subjected to millimeter-level solid-liquid separation to obtain a cellulose-rich solid phase and a lignin-rich liquid phase.

7. The method for graded utilization of all components of Reed sphagnum moss using segmented, fiber-guided crushing according to claim 6, characterized in that, The second membrane integrated purification and solvent recovery system includes a first membrane purification branch, a second membrane purification branch, and a common solvent recovery unit arranged in parallel. The first membrane purification branch is used to process hemicellulose sugar solution and consists of the following components connected in sequence: a microfiltration or ultrafiltration membrane module for retaining residual solid particles, a first nanofiltration membrane module for separating oligosaccharides, a second nanofiltration membrane module for desalting monosaccharides, and an ultrafiltration membrane module for purifying the sugar solution; after processing by this branch, xylose or syrup products are obtained. The second membrane purification branch is used to process the lignin-rich liquid phase and consists of the following components connected in sequence: a microfiltration or ultrafiltration membrane module for filtering out trace fibers and colloids, a nanofiltration membrane module for concentrating lignin and dialysis to recover sulfuric acid, and a distillation unit for separating the product from the lignin concentrate; after processing by this branch, a high-purity lignin product is obtained and ethanol is recovered. A shared solvent recovery unit is used to receive and process solvent-containing streams generated from each branch to recover and recycle ethanol, water, and sulfuric acid from the process.

8. The method for graded utilization of all components of Reed sphagnum moss using segmented, fiber-guided crushing according to claim 6, characterized in that, The cellulose-rich solid phase separated in step S325 is high-purity cellulose, which is subjected to high-value conversion through at least one of the following methods: a. Fiber grading: The fiber is dispersed in water and mechanically decomposed and sieved to obtain long fibers with a mesh size greater than 100, medium fibers with a mesh size of 100 to 200, and short fibers with a mesh size less than 200. b. Nanofiber preparation: Short fiber slurry was modified by carboxymethylation and then homogenized under high pressure to prepare microfibrillated cellulose and fibrous nanofibers; c. Nanocrystal preparation: Cellulose nanocrystals are prepared by acid hydrolysis of microfibrillated cellulose and fibrous nanofibers.

9. A method for graded utilization of all components of Reed sphagnum moss using segmented, fiber-guided crushing according to claim 7, characterized in that, Xylose or syrup products are used as fermentation raw materials to derive polylactic acid (PLA) series products through the following pathways: Fermentation and purification: After detoxification, decolorization and concentration adjustment, it is used as a fermentation raw material, and high-purity lactic acid is obtained through microbial fermentation and purification; L-lactide synthesis: High-purity lactic acid is purified by dehydration condensation, depolymerization cyclization and distillation to obtain L-lactide and D-lactide products with high optical purity. Polymerization Derivatization: Polylactic acid products are prepared using high optical purity L-lactide and D-lactide as raw materials through at least one of the following methods: copolymerization reaction to prepare polyracemic lactic acid; Stereocomposite reaction to prepare stereocomposite polylactic acid; High molecular weight polylactic acid bioresin was prepared by ring-opening polymerization using L-lactide or a mixture of L-lactide and D-lactide as monomers.

10. A method for graded utilization of all components of Reed sphagnum moss using segmented, fiber-guided crushing according to claim 9, characterized in that, High molecular weight polylactic acid bioresin and high purity cellulose were melt-blended and granulated at a mass ratio of 6:4 to prepare bamboo-based plastic composite material particles.

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