WO2023132814A1

WO2023132814A1 - Method of obtaining chemical-thermomechanical fibrous mass from plant raw materials and systems for its realization

Info

Publication number: WO2023132814A1
Application number: PCT/UA2022/000019
Authority: WO
Inventors: Valentin Mikhailovich FRECHKA
Original assignee: Releaf Paper France Sas
Priority date: 2022-01-04
Filing date: 2022-04-19
Publication date: 2023-07-13

Abstract

A method of obtaining a chemical-thermomechanical fibrous mass (CTFM) from plant raw materials with forming an automated plant processing line, wherein providing the plan raw material plastification by mechanical interaction of the plant raw material particles under conditions of high pressure and temperature by a hydrothermal impregnation. Saturating with alkali an obtained thermomechanical plasticized mass (TPM) by using a chemical- thermomechanical chamber without pressure. Performing a stepwise dewaxing with neutralization of an alkali, and precipitating of a residual lignin in a solution of a low concentrated acetic acid, bleaching of the CTFM by using an acetic acid.

Description

Method of obtaining chemical-thermomechanical fibrous mass from plant raw materials and systems for its realization

CROSS-REFERENCES TO RELATED APPLICATIONS

The present patent application claims priority to Ukrainian patent applications a202200999 filed March 23, 2022 and u202200037 filed January 04, 2022.

FIELD OF INVENTION

The claimed invention relates to a pulp and a paper industry, namely to a method of manufacturing paper products using non-woody plant biowaste, for example fallen leaves.

BACKGROUND

With a global developing of industry, trading, logistics different paper products are becoming more popular. In addition, as usual use for printing and stationery, the paper has become an excellent alternative to polymeric materials in the manufacture of various types of packaging, utensils, and other products, which has led to a significant increase in wood use and requires ways to reduce such use.

Today, the main ways to reduce the usage of wood in the paper manufacture products can be a paper recycling, as well as search for alternative raw materials as a source of cellulose.

Another aspect of the claimed invention comprising reduce hazardous waste and resources for the production of pulp and paper products.

To solve named problems, the RELEAF PAPER technology was developed and implemented in production, which involves the use of a new method of manufacturing a fibrous product for the production of paper products of a plant biomass, such as plant waste or fallen leaves.

It is known from the prior art the patent RU2736428, wherein a method of obtaining a fibrous Miscanthus semi-finished product, which includes the preparation of Miscanthus stalks by grinding into a chaff. On the next step providing the chaff thermochemical treatment in an alkaline environment at elevated temperature, grinding to obtain fibrous mass, sorting mass thickening and bleaching. Miscanthus chaff is pre-impregnated in a solution containing alkali metal hydroxide, surfactants, and stabilizer, at a temperature near 70°C for 0,5-12 hours, with followed separating of the solution from the chaff. Then providing its thermochemical treatment in an alkaline environment at a temperature of 80-120°C for 20-60 minutes, then the chaff is thickened to a concentration of 60-70% with the separation of spent alkaline solution, diluted with water or a solution of bleaching chemicals and ground to obtain a fibrous mass. Sorting the mass, wherein a separated waste is grounding together with a sieve after thickening. After one cycle of the impregnating, strengthing a solution is with a concentrated solutions of alkali metal hydroxide, surfactant and stabilizer to the concentration of the initial solution and reused. Finished 13-15 cycles of the solution is sent for regeneration.

There are several other known methods of obtaining non-wood pulp. For example, the closest analogue is the method described by KR20150085179A, wherein a production of paper by using leaves is based on the method of fiber extraction, by action on the leaves with organic solvents. According to known technology, providing a stage of leaves cleaning, grinding, extracting fiber by centrifuging of the crushed mixture, mixed with a solvent to separate the pigment from the main fiber. The pigment solution may contain methyl ester of acetone, ethyl ether, diethyl ether, hexane and palm oil. The disadvantage of this method is:

- high cost of solvents;

- high level of solvent toxicity, which requires the creation of special working conditions in the workplace;

- low ability of solvents to dissolve lignin polymers, which reduces the mechanical strength of the fiber;

- the liquid products disposal complexity during leaf processing.

It is also known a method of obtaining long-fiber cellulose oof a pineapple leaves by fine processing of biomass according to the invention CN 104674353 A, where providing a first fibers pre-ultrasonic treatment; further processing for swelling of fibers which is carried out by special chemical reagents; providing the fibers chemical treatment after the swelling; at the end of the process, combedding, crushing and drying the pineapple leaf fiber.

The disadvantage of this method is:

-high costs for ultrasonic treatment of raw materials.

-this method does not allow to remove large molecules of lignin incrustator, which makes the fiber brittle and unstable to UV rays.

Another known technology is described by a patent, GB2283989A, wherein disclosed an information of a possibility to obtaining a mass of banana leaves by an alkaline process and relates to an unbleached cellulose production. The known technology comprising steps of using a banana leaf biomass under the following processing conditions: caustic soda 12% (NaOH), maximum temperature 150°C, duration 3 hours.

The present technology eliminates disadvantages of the technologies/methods described by KR20150085179A, CN104674353A and GB2283989A. The developed technology, which has become the object of protection, is based on the technology of obtaining plant fibers from non-wood raw materials, such as fallen leaves or stems of plant waste, by chemical-thermomechanical dispersion in a slightly alkaline medium with acetic acid deposition of lignin. 0

The disadvantages of the known methods include the high cost of solvents, the high level of toxicity of solvents, which requires special working conditions in production and complicates the disposal or processing of liquid products of leaf processing. Disadvantages also include a low ability of these solvents to dissolve 5 lignin polymers, which reduces the mechanical strength of the fiber.

The claimed technology solves said disadvantages of the prior art and allows processing of different types of raw materials within a single automated plant processing line, with the ability to change the stages, which makes it unified and 0 mobile. This approach reduces water and energy costs, making the method cost- effective and environmentally friendly.

The technical problem to be solved by the invention is to create and implement a method of obtaining semi-cellulosic fibers from non-wood cellulose, such as 5 fallen leaves, by chemical-thermomechanical treatment of a plant raw material in a weak alkaline medium with an acetic acid deposition of lignin.

The technical result obtained by the invention consists of minimizing water and energy resources with increasing the plant fiber yield relative to the weight of raw10 materials used. In particular, the proposed method reduces resource values to: 52 kg of alkali, 450 kW of electricity, 6 m3 of water, 120 m3 of gas per 1 ton of finished fiber.

SUMMARY OF THE INVENTION 15 The essence of the claimed invention is to implement a method of obtaining a chemical-thermomechanical fibrous mass (CTFM) from plant raw materials with forming an automated plant processing line, wherein separating a previously untreated raw material out of foreign inclusions without a plant fiber. Crushing the raw material by fractions and sorting the plant raw material with followed20 drying and granulation. Processing the plant raw material with including at least steps of delignification, purification and bleaching of the plant fiber suitable for the production of paper products. According to the method, forming one of the automated line module, wherein providing the plan raw material plastification by mechanical interaction of the plant raw material particles under conditions of high25 pressure and temperature by a hydrothermal impregnation. Wherein saturating with alkali an obtained thermomechanical plasticized mass (TPM) by using a chemical-thermomechanical chamber without pressure. Performing a stepwise dewaxing with neutralization of an alkali, and precipitating of a residual lignin in a solution of a low concentrated acetic acid, with bleaching of the CTFM by using30 an acetic acid.

According to the method analyzing a Neutral detergent fiber (NDF) of the plan raw material sample before the processing starts of, wherein determining the fiber rate suitable for paper products production. 35

According to the possible variant of the method using fallen leaves as a main source of the plant fibrous mass. Wherein using a Straw, a Reed, a Miscanthus, and an Arundo in combination or separately as the source of the plant fibrous mass. Using the plant fibrous mass wherein characteristics of production 0 requirements, comprising the plant fiber mass rate in the final paper product of at least 30%. The method comprising steps of separating the plant fiber mass from the foreign inclusions, by using by a cylinder perforated separators and aerocyclones, which are forming one of the modules of the automated line.

The method according to the claim 1 wherein providing the hydrothermal impregnation under the pressure by using a sealed screw chamber, which is a part of the automated line. Providing the hydrothermal impregnation with temperature above 100 ⁰ C.

The thermomechanical mass delignification comprising steps of dissolving lignin and hemicelluloses, by washing out of the plant fiber by using condensate of a steam supplied to the chemical-thermomechanical fibrous mass.

The stepwise dewaxing comprising at least a primary dewaxing with a presence of a low concentration acid solution (<2%) and secondary fibrillation with a complete dewaxing, by using conical mills at low mass concentration.

According to the present invention the bleaching step comprising at least two cycles, wherein providing a continuous circulation of heated bleach solution with high concentration of the plant fibrous mass.

The described method according to the claimed invention can be implemented based on a system for obtaining chemical-thermomechanical fibrous mass from plant raw materials comprising: an automated plant processing line which is consists of at least unit (1) for mechanical separation of the plant raw materials out of foreign inclusions without a plant fiber, a separation block (A), a convection dryer block (C), a sorting and grinding block (D), a granulator (E). Wherein the system comprising at least a delignification block (H). The automated plant processing line comprising a chemical-thermomechanical processing unit (2) which is comprising a sealed thermomechanical screw disperser (G) with changable temperature and pressure parameters. Wherein thermomechanical screw disperser (G), is connected to the delignification block in a form of chemical-thermo-mechanical chamber (H) with steam supply system, which in turn is connected to block of the plant raw material dewaxing based on a high concentration defibrillator (I), a block alkali neutralization by a high- concentration hydro pulper (J) and bleaching blocks.

The block alkali neutralization by the high-concentration hydro pulper (J) with a low rotor.

Wherein the bleaching block comprising at least perforated cylinders mounted in sealed cylinders that are designed as the automated line part.

DESCRIPTION OF THE DRAWINGS

The essence of the claimed invention is explained, but not limited to the following graphic materials:

Figure 1 - is shown a schematic diagram of a system for obtaining chemical- thermo-mechanical fibrous mass from plant raw materials;

Figure 2 - is shown a structure of plant raw materials.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of the claimed invention will be described below.

In the text of the description synonyms for the expression "chemical- thermomechanical fibrous mass" can be considered:

Fibrous mass;

Semi-fibrous mass;

Fibrous semi-fmished product;

Semi-cellulose. Based on possible embodiments of the invention, the terms: "plant raw materials", "plant biowaste" may include:

Fallen leaves (target raw materials);

Straw: wheat, barley, rice;

Biomass for processing sugar cane (bagasse);

Arundo;

Biomass after coconut processing;

Biomass after processing pineapples;

Biomass after processing of banana fruits;

Biomass after processing banana stalks;

Needles from representatives of gymnosperms;

Stems of Hops.

According to possible embodiments of the invention, the claimed technology can be implemented in production of:

Calendered kraft paper;

Kraft paper not calendered;

Paper bags;

Cardboard;

Corrugated cardboard;

Cast containers by type: egg gasket, egg box, logistics packaging;

Building materials: gasket for the floor, bulk insulation;

Containers for seedlings and plants;

Decorative materials and fillers.

The plant raw materials are grouped into at least two groups: mechanically stable group (SPG-002) and delicate group (LPG-001) depending on the part of the plant, mechanical strength, and quality composition, which determines the stages of the technological process within one line. (1) Delicate Group (LPG-001) is mainly relates to leaves, as it mainly performs photosynthesis and gas exchange. The leaves structure is very fragile because it does not have strong trophic tissues that would contain fiber similar to the fiber in a bark, for example. That is why excluding a hard machining and long-term treatment with alkali at extremely high temperatures out of the technological process of processing eliminates for preserving the integrity of fibers and maximum mass yield.

Delicate group (LPG-001) includes:

1.1. Fallen leaves of deciduous trees of temperate, tropical, and equatorial poles, namely: Betula borysthenica Klokov, Betula pendula Roth., Ulmus minor, Fagus sylvatica L., Fagus orientalis, Ulmaceae, Salix L., Alnusincana, Aesculus hippocastanum, Carpinus betulus L., Quercus robur L.,Quercus rubra (Quercus borealis), Catalpa bignonioides Walt., Castanea sativa, Acer platanoides L., Acer campestre, Tilia platyphyllos, Populus tremula L., Platanus, Rhus L., Populus nigra L., Fraxinus, Prunus cerasus L., Juglans regia L., Morus, Pinus sylvestris L., Acacia, Paulownia, Paulownia fortunei, Paulownia elongata, Paulownia Cion in Vitro 112, Citrus sinensis, Citrus reticulata, Diospyros, Ficus, Acer saccharum Marsh., Vitaceae, Humulus L., Ginkgo, Ginkgo biloba, Robinia pseudoacacia, Tectona grandis, Shorea robusta, Phoenix dactylifera..

1.2. Deciduous biomass of the genus Banana grass (Musa).

1.3. Modified leaves (needles) of gymnosperms.

(2) Standing Group (SPG-002) is mainly relates to the stem, because it performs a trophic and conductive function, it contains longer fibers, more branched fractions of lignin and has a higher degree of mechanical strength compared to the leaves. In order to obtain a fibrous mass, at firs it must be freed from inlays, xylans and other compounds, which is possible under more aggressive conditions of pressure, temperature and degree of alkalinity.

Mechanically stable group (SPG-002) includes: 2.1. Bonfire stems part of some members of the family of cereals (Poaceae , namely: Avena, Chloris, Cortaderia, Hordeum, Oreobambos, Oryza, Panicum, Phragmites, Saccharum, Secale, Sorghum, Triticum, Zea.

22. Stem part of Arundo donax.

2.3. Fruit part of biomass after processing of coconut Cocos nucifera).

2.4. Rosettes, leaf, and fruit biomass after processing of Ananas comosus.

2.5. The twisted part of the stem is the part of Flops (Humulus L.).

2.6. Stems of Japanese buckwheat (Reynoutria japonica .

2.7. Stem part of edible tomatoes (Lycopersicori .

2.8. Twisted part of grape stalks (Vids').

According to one of the possible embodiments, the present invention is describing a system for producing chemical -thermo-mechanical fibrous mass from vegetable raw materials. Said system can be constructively implemented based on an automated plant processing line formed according to the scheme (Figure 1).

The automated plant processing line comprises at least module 1 for mechanical separation of the plant raw material out of foreign inclusions not containing a plant fibers, where the plant raw material is fed to a separation block (A), such as a drum separator in which sand, stones, heavy non-plant inclusions are removed through the perforation and purge air flows, or light fractions, such as polyethylene.

According to one of the possible embodiments of the invention, the drum separator can be equipped with internal ribs and placed at an angle, while, as it rotates clockwise, the plant raw material moves along the separator, thereby being unloaded into the washing basin, block (B). The washing basin (B) can be filled with a bactericidal solution to inactivate living microorganisms. Due to the circulation of water, the plant raw material moves along the washing basin and is fed to the vibrating conveyor, which moves through a tunnel of a convection dryer block (C).

The plant raw material may be dry or wet, but it is in any case is free of pollutants, bacteria, fungal spores and dried for long-term storage. After the dryer block (C), the plant raw material moves grinding block (D) with next granulator (E) and forming fractions (granules) in a shape convenient for storage with a particle size of 1 to 2 cm, for next storing in a separate warehouse.

The granulation process allows increasing the bulk density of raw materials. Depending on the type of the plant raw material, the technology allows obtaining, for example, a cylindrical granule with a diameter of 1 cm and a length of 2 cm, or a briquette 2x2 cm.

Further, according to production needs, the granulated plant raw material may be overloaded by the screw conveyor to the next module of the automated plant processing line. This embodiment of the invention allows obtaining the most selective plant raw materials for cost-effective storage, transportation, and subsequent use.

Impregnating processing with the transferring to thermomechanical processing, which is realized by a chemical-thermomechanical processing module 2, wherein the dry granular plant raw materials moving through the screw mixer-conveyor (F) into the thermomechanical screw disperser block (G) is designed as a sealed screw chamber with a changeable internal temperature and pressure parameters. At this stage, a plastification of the plant raw materials is realized by the mechanical interaction of the plant raw material particles under conditions of a high pressure and temperature.

Water steam is supplied to the dispersant under pressure and high temperature. The main task of this stage is to make the plant raw material plastic, swollen, more homogeneous. Because this process is provided in a humid environment and at high temperatures, some organic molecules will be dissolved, proteins are denatured, etc., which will simplify further processing of the plant raw materials. Pushing out by pressure and rotational movements, the plasticized mass enters delignification block (H) which is designed as a chamber of chemical- thermomechanical treatment under conditions of high pressure.

The delignification is provided with the stepwise splitting of fibers, neutralization of alkali, and precipitation of residual lignin in a solution of weakly concentrated acetic acid, followed by bleaching of the fibrous mass with acetoperhydrol agent. At the delignification block (H) the plant raw material is actively mixed, the plasticized mass is saturated with alkali, which providing a degradation of most compounds and the transition of lignin to a soluble phase. Due to the formation of condensate, the semi-fibrous mass is well washed from lignin. Alkali is fed into the chamber through aerosol nozzles, process pH in the range of 10- 13, active alkali concentration 2-5%, operating temperature 120-150°C, pressure in the range of 0.4-1 MPa.

Following the same principle as a thermomechanical screw disperser, the plant raw material is discharged into a high concentration defibrillator block (I). Wherein breaking down cellulose fibrils and making the fiber smaller by the defibrillator block. Thanks to high rate plasticization of biomass and its release from the inlays, the fiber is no longer brittle and is well cleavable. This block is formed to obtain a high-yield fibrous mass, which is well ground. The defibering module 3 of the plant raw material dewaxing, involves at least primary defibering in the presence of weakly concentrated acid (<2%) and secondary fibrillation with complete defibering, which is performed by conical mills (L), (K.) at low mass concentration.

As the size of the fibers decreases, together with the flow of water, the fibrous mass passes through the grinding disc of the defibrillator block (I) and pumped into the high-concentration hydro pulper block (J), where the acetic acid solution is fed. As the result of high-concentration hydro pulper block (J) operation, providing the precipitation of integral lignin, pH equalization, and compression of cellulose fibrils.

Defibrillator block (I) action takes about 10-20 minutes, after which under self weight pressure, distributing the fibrous pulp between the a first-order conical mill (K) and a second-order conical mill (L). At this stage, the degree of grinding of the fibrous pulp is from 15 to 22 degrees Schopper- Riegler (°SR). Since the plant raw materials of non-wood origin have a very fragile structure, the mode of grinding in conical mills can occur in several ways:

-Both mills are involved, the concentration on the first-order conical mill is high, on the second-order conical mill is low.

-Only one conical mill is involved, the concentration is high, the grinding time is short.

-Only one conical mill is involved, the concentration is low, the grinding time is short.

-Only one conical mill is involved, the concentration is low, the grinding time is long.

Conical mills are made with the ability to adjust the degree of closure of the headset, which depends on the time of passage of the mass through the mill, which affects the subsequent degree of grinding. In this method, the optimal degree of grinding can be set to 26-30 degrees Schopper-Riegler (°SR).

Based on a reason that in the previous stages, there is a possibility that certain particles may be present in the biomass that has not split into fibers. That is why after all production stages providing screening at a vibrating sorting platform block (M) with spraying water for better separation of fiber from non-fibrous inclusions. Such placing of the screening block allows to reduce material loss.

The present invention is not limited to the use of screening at this stage. The screening blocks can be divided into several stages, but it may depend only on the plant raw material characteristics, as well as quality and economic requirements. After screening, almost 100% of the fibrous mass enters the mass thickener block (N), wherein it is further distributed to the production of paper products.

It is important to note that in the proposed method, at the stage of dispersion and chemical-thermomechanical treatment, the usage of a large volume of water is excluded, ie the raw material is processed in a humid environment, but not in solution. This reduces the cost of water and steam to heal the environment. According to the results of the examination, this process is characterized by the following indicators of resource costs for the production of 1 ton of mass.

(Table No 1):

The delignification block (H), in turn, is connected in series with the specified units of the raw material dewaxing module 3, which also provides alkali neutralization. The automated line may additionally be equipped with a fiber bleaching block, which may include concentration perforated cylinders installed within mounted in sealed cylinders (containers) (not shown in the figures).

The blocks of purification (dewaxing) of the plant raw materials and neutralization of alkali can be made in the form of a high-concentration hydro pulper with a lower rotor.

The described schematic diagram of the installation may be modified depending on the types of plant biowaste.

Dividing the raw material into two groups, the stages of processing for the delicate group (LPG-001) are:

according to the scheme (Figure 1).

For the stable group (SPG-002) there are:

according to the scheme (Figure 1).

It is known from the prior art that, as a rule, cellulose fibers are suitable for paper production, denoting a set of lignin-free cellulose fibers obtained by chemical or mechanical methods from wood.

Much of the world's pulp production is wood pulp, and the wood used for pulp production is softwood with low resin content, high fiber length, and low density. The claimed invention provides for the use of vegetative organs of the tree, such as fallen leaves, which are renewed annually and are formed in large quantities, for example, in urban ecosystems (cities). In any case, the leaves that fall in cities accumulate around roads, parks, squares, and need to be disposed of properly, as they can harm the urban environment when mixed with general rubbish or open rot.

The main source of fibrous mass is fallen leaves with characteristics that meet production requirements, with a mass fraction of plant fiber in the final product (paper product) of at least 30%. Also, following possible variants of the invention as vegetable raw materials, if necessary, can use Straw, Reed, Miscanthus, Arundo.

As part of the tree, the leaf also has vessels (Figure 2), which consist of fibrous bundles formed by phloem and xylem. Consider a picture "A" (Figure 2), which shows the structure of the leaves leg (petiole) 4, central vein 5, peripheral veins 6. Considering the sheet as a whole, the focus of raw materials, according to the claimed technology, will fall on these structural elements. If we look at the leaf at the anatomical level, picture "B" shows components such as cuticle 7, epidermis 8, columnar parenchyma 9, xylem 10, phloem 1 1 , spongy parenchyma 12. The element xylem 10 is the main source of cellulose when using leaves as vegetable raw materials in the implementation of the invention. Xylem 10 itself is a mechanical tissue that divides into vessels and tracheids. Vessels - long hollow tubes formed from a vertical row of parenchymal cells. Tracheids are elongated dead cells without cytoplasm. The lignocellulosic complex makes up most of the vessels and tracheids.

In the leaf, the lignocellulosic complex is presented in the form of cellulose chains in which such components as hemicelluloses, lignins, pentosans, etc. are integrated. Picture "C" depicts lignocellulose complex 13, integral lignin 14, lignin 15, residual lignin 16, hemicellulose 17, inclusion 18, hemicellulose 19, bound hemicellulose 20. The method claimed in the invention involves the release of cellulose from lignocellulose 13 method PI1 / 1 - DE2 / 2. The length of such fibers, depending on the leaf particle and wood species, is 0.3 - 4 cm. However, since the main function of the leaf remains photosynthesis and gas exchange, the fiber has lower physical and mechanical properties than wood. This is because the leaves must fall off each season and decompose quickly. This leads to complicated processing of leaves with traditional known methods of processing raw materials with sulfur-containing reagents or highly alkaline solutions. This affects the lower fiber yield (10-20%), fiber shortening, fiber destruction, and so on.

The Re-leaf technology claimed by the essence of the invention allows to obtain a fiber under optimal conditions where the integrity of the fiber is preserved, but most of the inlaying components are separated.

According to the described system of implementation of the invention, the claimed method can be embodied by processing plant biomass into a semi-fibrous product on the example of fallen leaves. The results of processing of various raw materials will be given below (see Table 2; 3), based on the calculation model, where the reference sample is prepared raw materials weighing 1000 grams.

Pre-treated raw materials in the form of a mix of fallen leaves with various inclusions that do not contain plant fibers, separated from the inclusions, washed from sand and dust, and then perform convection drying to a moisture content of not more than 10%. At this stage, the preparation of raw materials is performed by perforated drum separators and aerocyclones, forming one of the modules of the automated line 1 .

The raw material sample is ground to a particle size of 1 to 3 cm, sorted and granulated. The prepared dry mass is loaded into a sealed screw chamber for heating under pressure with the possibility of mixing, with an electric heating element, where it is kept for a specified period under a pressure of 0.5-1 MPa, at a controlled temperature of more than 100°C and 1 :5. This process provides hydrothermal impregnation of the mass and gives it plastic properties by mechanical interaction under conditions of high pressure and temperature.

In the next stage, the plasticized mass is washed and loaded into an unsealed screw mixer, in the form of a chemical-thermo-mechanical chamber without pressure heated to 80-100°C, into which the delignificating alkali solution is fed. This process can take about 30 minutes. During this time, the plastic absorbs the active alkali, which leads to partial delignification and release of the fiber, which may be suitable for paper production. Delignification of the thermomechanical mass involves the dissolution of lignin and hemicelluloses, which are washed out of the fibers by condensate formed by the supply o f steam to the chemical - thermo-mechanical chamber. This solution significantly reduces water use.

Thereafter, the delignified mass is loaded into a high concentration hydropulper with a lower rotor, the partially delignified mass is subjected to partial dewaxing for 5-10 minutes. Then a weakly concentrated acetic acid solution (<2%) acetic acid solution is added to the mass, the dewaxing process continues. At this stage, integral lignin precipitates, the fiber acquires properties that determine its further grinding and the ability to produce paper, the medium acquires a pH value of 6. Acetic acid neutralizes alkali, which stabilizes the delignification process and leads to its precipitation. That is, the fiber is released from N% lignin, which makes it elastic and suitable for further complete defibering.

Further, the partially mass of split fibers, devoid of most lignin content, is washed and split into fibers in full compliance with ISO 5264-1, TAPPI T 200m, T 205m, SCAN C 25, CPPA C.2. Deferment lasts an average of 15-20 minutes under load. This mode allows you to achieve a degree of grinding mass of 22-25°SR and preserve the integrity of the fibers. Grinding is completed by washing and casting a paper sample of 100% fiber and in a mixture with waste paper brand MS-5B in different proportions.

The bleaching step involves at least two cycles performed in concentration perforated drums mounted in sealed cylinders that form one of the modules of the automated line, with continuous circulation of heated bleach solution and high concentration of fibrous mass.

In the present embodiment of the invention, acetoperhydrol two-stage bleaching is provided. A high concentrate of the bleached fibrous mass is fed into the perforated drums. The bleaching process is provided by two components: perhydrol and acetic acid, which together make peracetic acid. The reaction is catalyzed by alkali at a pH of 8.5. Concentrations of components are selected so that the fiber is not subject to destruction, and in the second stage of bleaching, before washing, the bleaching solution was with a neutral pH. The bleaching step involves at least two cycles performed in concentration perforated drums mounted in hermetic cylinders that form one of the modules of the automated line, with continuous circulation of heated bleach solution and high concentration of fibrous mass.

Casting of paper products, in one of the variants can be carried out on a paper machine with an inclined mesh table and an open pressure box at a rolling speed of 2.15 m\min.

According to various embodiments of the invention, the raw materials used and the concentration of substances, according to the results of laboratory studies, the claimed method allows to obtain the following indicators:

Yield of fiber from fallen leaves based on wet material (Table 2):

The (Table 3) shows the test results of paper products, namely paper from a mixture of fallen leaves, hop stalks, pineapple tops and the same mixture with waste paper brand MS-5B. Testing was performed in accordance with the following standards: BDS EN ISO 536: 2020 Paper and cardboard - Determination of weight of 1 m2 of paper (ISO 536: 2019);

The claimed invention implements a protocol before production preparation, namely the analysis of a biomass sample for the content of neutral detergent mass - NDM (Neutral detergent fiber - NDF) by deep processing. This stage can be carried out immediately before production or in the field at the stage of raw material collection. The purpose of the analysis is to determine the fiber content suitable for the production of paper products and by-products. It is an integral part of the process, as it allows you to predict the cost of energy, water resources, preparation of facilities for wastewater treatment.

According to one of the possible embodiments of the invention, the kit for analysis may include: laboratory scales, mobile hygrometer, pH meter, distilled water, sodium hydroxide solution, acetic acid solution, additional equipment.

The algorithm according to the protocol of pre-production preparation provides the following actions:

(1) Take a biomass sample.

(2) Determine the initial relative humidity.

(3) Grind the sample portion, add EDTA (Ethylene diamine tetra acetic Acid) and heat but do not boil for 10 minutes. In this case, there is decompression of cellulose fibrils, which will further facilitate its isolation.

(4) After heating, drain the solution and rinse the mass and grind.

(5) Add sodium hydroxide solution to the suspension, boil for 20 minutes. This process will ensure the dissolution of lignin, the separation of hemicelluloses, the dissolution of xylan, and the destruction of proteins, amino acids and other compounds.

(6) After boiling, drain the solution and wash the mass from the delignification solution.

(7) Dissolve the fibrous mass in acetic acid solution and grind. Acetic acid acts as a pH stabilizer and precipitates integral lignin, provides compression of cellulose fibrils.

(8) Wash the resulting mass and dissolve in additional EDTA and heat, but do not boil for 10 minutes. EDTA provides at this stage re-decompression of cellulose fibrils. As a result of this action, the fiber is released from most non-fibrous inclusions that are not suitable for the production of paper products.

(9) After heating, drain the solution and wash the mass, squeeze the mass, measure the moisture and determine the relative yield of the fibrous mass based on the weighing method.

Thus, this analysis makes it possible to determine the theoretical yield of fiber suitable for the production of paper products in the field, well in advance before preparing the raw material for processing. Also, the obtained fiber sample can serve as a breakdown for microscopy, determination of the possible degree of grinding, fiber length, ash content, and so on.

Casting of paper products, in one of the variants can be carried out on a paper machine with an inclined mesh table and an open pressure box at a rolling speed of 2.15 m \ min.

For the manufacture of paper products can use the following raw materials:

- chemical-thermomechanical mass (CTMM) from plant biomass by current regulations, formed by the stages; - fibers processed (waste paper) brands MS-3 A, MS-5B-1, MS-5B-2, MS-5B-3, MS-6B-1, MS-8V-1 in accordance with State Standards of Ukraine (DSTU) 3500;

- intramass glue AKD (alkyl-keten dimer) by current regulations;

- water-repellent resin by current regulations;

- com starch modified by State Standards of Ukraine (DSTU) 4380.

Features of the fibrous mass, which is obtained by the claimed technology, form the relevant requirements for the technological process, namely, the preparation of production machines for the production of paper products. For example, if you make paper from 100% fiber from fallen leaves or straw, reduce the speed of the forming part of the paper machine and choose the appropriate drying mode. At the same time, cast products (vacuum forming method), such as egg trays, require less time to dry and do not deform during drying due to greater porosity.

Several tests have shown that paper can also be made in a composition with recycled waste paper fibers. You can consider a paper product, a product of fallen leaves or straw, if the unit weight is at least 30% by weight of alternative fiber, in this case, obtained from fallen leaves.

For the manufacture of cast paper products, for example, egg pads use the following raw materials:

- chemical-thermomechanical mass (CTMM) from plant biomass by current regulations;

- processed fibers (waste paper) of the MS-5B-2 brand;

The results of laboratory tests show that this type of product is characterized by the speed of drying after molding and does not require the use of adhesive components. The possibility of using 100% of fibers of non-wood origin, such as fallen leaves, has also been confirmed.

Claims

1. A method of obtaining a chemical-thermomechanical fibrous mass (CTFM) from plant raw materials with forming an automated plant processing line, wherein separating a previously untreated raw material out of foreign inclusions without a plant fiber, crushing by fractions and sorting the plant raw material with followed drying and granulation, processing the plant raw material with including at least steps of delignification, purification and bleaching of the plant fiber suitable for the production of paper products; wherein forming one of the automated line modules, wherein providing the plan raw material plastification by mechanical interaction of the plant raw material particles under conditions of high pressure and temperature by a hydrothermal impregnation; wherein saturating with alkali an obtained thermomechanical plasticized mass (TPM) by using a chemical-thermomechanical chamber without pressure; performing a stepwise dewaxing with neutralization of an alkali, and precipitating of a residual lignin in a solution of a low concentrated acetic acid, bleaching of the CTFM by using an acetic acid.

2. The method according to the claim 1 wherein analyzing a Neutral detergent fiber (NDF) of the plan raw material sample before the processing starts of, wherein determining the fiber rate suitable for paper products production.

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3. The method according to the claim 1 wherein using fallen leaves as a main source of the plant fibrous mass using the plant fibrous mass wherein characteristics of production requirements, comprising the plant fiber mass rate in the final paper product of at least 30%.

4. The method according to the claim 1 wherein separating the plant fiber mass from the foreign inclusions, by using by a cylinder perforated separators and aerocyclones, which are forming one of the modules of the automated line.

5. The method according to the claim 1 wherein using a Straw, a Reed, a Miscanthus, and an Arundo in combination or separately as the source of the plant fibrous mass.

6. The method according to the claim 1 wherein providing the hydrothermal impregnation under the pressure by using a sealed screw chamber, which is a part of the automated line, wherein providing the hydrothermal impregnation with temperature above 100 ⁰ C.

7. The method according to the claim 1 wherein the thermomechanical mass delignification comprising steps of dissolving lignin and hemicelluloses, by washing out of the plant fiber by using condensate of a steam supplied to the chemical-thermomechanical fibrous mass.

8. The method according to the claim 1 wherein the stepwise dewaxing comprising at least a primary dewaxing with a presence of a low concentration acid solution (<2%) and secondary fibrillation with a complete dewaxing, by using conical mills at low mass concentration. The method according to the claim 1 wherein the bleaching step comprising at least two cycles, wherein providing a continuous circulation of heated bleach solution with high concentration of the plant fibrous mass. A system for obtaining chemical-thermomechanical fibrous mass from plant raw materials comprising: an automated plant processing line which is consists of at least module (1) for mechanical separation of the plant raw materials out of foreign inclusions without a plant fiber, a separation block (A), a convection dryer block (C), a sorting and grinding block (D), a granulator (E), wherein the system comprising at least a delignification block (H); wherein the automated plant processing line comprising a chemical- thermomechanical processing module (2) which is comprising a sealed thermomechanical screw disperser block (G) with changeable temperature and pressure parameters, wherein thermomechanical screw disperser (G), is connected to the delignification block in a form of chemical-thermo-mechanical chamber (H) with steam supply system, which in turn is connected to a module (3) of the plant raw material dewaxing based on a high concentration defibrillator (I), a block alkali neutralization by a high-concentration hydro pulper (J) and bleaching blocks. The system according to the claim 10 wherein the block alkali neutralization by the high-concentration hydro pulper (J) with a low rotor. The system according to the claim 10 wherein the bleaching block comprising at least perforated cylinders mounted in sealed cylinders that are designed as the automated line part.