Method for producing chemithermomechanical fiber pulp from non-wood plant raw materials and automated line for producing said pulp by said method

Abstract

1. A method for producing a chemi-thermomechanical fiber pulp from a non-wood plant raw material, comprising the steps of pre-preparing leaves, chemi-thermomechanical processing the pre-prepared raw material, and grinding the semi-fibrous and partially delignified pulp to produce a chemi-thermomechanical fiber pulp, wherein the pre-preparation of the initial raw material further comprises pressing the chopped leaves, the plasticization and softening of the pre-prepared leaves is carried out by mechanical rubbing thereof and treatment with pressurized heated steam, the delignification of the plasticized soft raw material is carried out by pressurizing and mixing them in the presence of an alkali metal hydroxide or in the form of a solution or aerosol with an alkali concentration of 3% or less at a temperature of 70-120°C and a pressure of at least 3.5 atm, and the grinding is carried out in the presence of acetic acid with a concentration of up to 3%.

Description

[Technical field]

[0001] The present invention relates to the field of cellulose, in particular to a technology for treating biowaste of plant leaves and subsequently producing a chemi-thermomechanical fibre pulp suitable for producing, for example, paper products, as well as to a line for producing said fibre pulp. [Background technology]

[0002] Chemi-thermomechanical fibrous pulp (or chemi-thermomechanical fibrous pulp) is a semi-finished product for papermaking that contains a set of lignin-free cellulose fibers that can be bonded together and are usually obtained from wood by chemical or mechanical methods.

[0003] The cellulose fibers are released from the wood by breaking down or dissolving the non-cellulose (or non-cellulose) components by chemical or mechanical treatment: the lignin is made soluble, part of the hemicellulose is hydrolyzed, the oligo- and monosaccharides formed are dissolved, and the undissolved remainder contains the cellulose fibers, which are then filtered and modified in a specific way.

[0004] Recently, there has been much focus on minimizing deforestation for papermaking needs, as well as minimizing waste emissions following processing of lignocellulosic feedstocks.

[0005] It is known that trees and other woody plants are not the sole source of fiber for making paper products. There are numerous annual and perennial plants whose leaves contain fibers of sufficient stiffness and length to produce paper of suitable quality. The fallen leaves of these plants are usually burned or decayed (or become tp decay). One of the main advantages of these fiber sources is that they are considered by the art as an environmentally friendly alternative to wood, are renewable annually and are formed in large quantities. However, the development of the non-wood fiber industry is not yet as available as wood fiber, due to the fact that non-wood cellulose is usually more expensive than wood cellulose. In addition, the treatment of leaves is usually complicated by the use of sulfur-containing reagents or highly alkaline solutions, thereby reducing the fiber yield (10-20%) and causing its shortening and destruction.

[0006] Many methods are known for producing non-wood cellulose.

[0007] For example, patent US9950858 relates to the production of cellulose materials from tobacco. The present invention provides tobacco-derived paper products, packaging materials and containers for tobacco products and other consumables and food products. In particular, the present invention discloses a fibrous material containing at least 10% by dry weight percentage of fiber derived from a plant of the Nicotiana species, as well as a method for producing such a fibrous material, which is based on treating different tobacco parts with sodium hydroxide at a concentration of 24% at a temperature of 160°C.

[0008] The patent document GB2283989 discloses the possible production of fiber pulp from banana leaves using an alkaline process and is related to the production of unbleached cellulose. The technology involves using banana leaf biomass with the following treatment conditions: caustic soda 12% (NaOH), maximum temperature 150°C, 3 hours.

[0009] The drawback of this method is the use of a significant number of high concentrations of alkaline solvents. Moreover, prolonged treatment at high temperatures and solvent concentrations reduces the fiber quality, i.e., its stiffness, thereby shortening the fiber "life" during subsequent processing to make products therefrom.

[0010] Patent document CN104674353 discloses a method for producing long fiber cellulose from pineapple leaves through a biomass refining process, which first includes ultrasonic pretreatment of the fibers, then a process for expanding the fibers using special chemical reagents, and after expansion, chemical treatment is carried out, and the method ends with degumming, chopping and drying of the pineapple leaf fibers.

[0011] The high cost for ultrasonic treatment of the raw materials is the main drawback of this method. In addition, the disclosed method does not allow to remove the large molecules of the lignin encrustrator, thereby making the fibers destructible and non-resistant to UV radiation.

[0012] The closest prior art to the claimed invention, disclosed in patent document KR20150085179, is a method for producing paper from leaves, which is based on a fiber extraction technique by subjecting the leaves to an organic solvent. According to the disclosed technique, the leaves are subjected to steps of washing, shredding, fiber removal by centrifugation of the shredded mixture, which is mixed with a solvent to separate the pigment from the main fibers. The pigment separation solution may contain acetone methyl ether, ethyl ether, diethyl ether, hexane and palm oil.

[0013] The disadvantages of this method are: - expensive solvents; -High toxicity levels of solvents that require providing special working conditions at industrial sites; - low ability of the solvent to dissolve lignin polymers, which reduces the mechanical stiffness of the fibers; - Complex disposal or processing of leaf treatment products. DISCLOSURE OF THEINVENTION [Problem to be solved by the invention]

[0014] It is therefore an object of the claimed invention to provide a method and an automated line for producing chemi-thermomechanical fiber pulp from various kinds of non-wood plant raw materials (delicate and stable groups of raw materials) with the aim of achieving the technical effect of producing chemi-thermomechanical fiber pulp that can be suitable for producing paper products of specific purposes, with the highest performance and the lowest cost, in an environmentally friendly way. [Means for solving the problem]

[0015] This object is achieved by providing a method for producing a chemi-thermomechanical fiber pulp from a non-wood plant material, the method comprising: - a step of pre-preparing the leaves, which step comprises at least separating the leaves from inclusions not containing plant fibres and shredding the separated material; chemi-thermomechanical treating the pre-prepared feedstock, the process including at least plasticizing the pre-prepared feedstock and delignifying the pre-prepared feedstock to produce a semi-fibrous and partially delignified pulp; grinding the semi-fibrous, partially delignified pulp to produce a chemi-thermomechanical fiber pulp; The initial feedstock pre-preparation step further comprises pressing the shredded leaves; The plasticization of the pre-prepared leaves is carried out by mechanical rubbing and treatment with pressurized heated steam, Delignification of the plasticized feedstock is carried out by pressurizing and mixing them in the form of a solution or aerosol having an alkali concentration of up to 3% or in the presence of an alkali metal hydroxide at a temperature of 70-120°C and a pressure of at least 3.5 atm; The grinding is carried out in the presence of acetic acid at a concentration of up to 3%.

[0016] The non-woody raw material, preferably fallen leaves, is a bio-waste occurring in cities, parks or other green areas. These leaves are preferably the annual portion of the plant, and therefore the useful parts of the leaves are very sensitive to mechanical treatments, in particular they can be severely damaged during the treatment. This leads to a strong shortening of the fallen leaf fibres in long-term chemical and mechanical treatments. The fallen leaf fibres are therefore too short to produce paper, as they lose their inter-bonding properties, which are important for providing the stiffness of the paper. The claimed method is particularly adapted to produce chemi-thermomechanical fibre pulp from non-woody plant raw material, avoiding said damage and shortening of the fibres.

[0017] These cellulose production conditions provide its softness, stiffness, and fiber integrity. The cleaned fiber pulp can be used to form paper products for various purposes, either from 100% fiber or in compositions with modified fibers such as recycled grades MS-5B, MS-8V, MS-3A, MS-2A, etc.

[0018] The claimed process allows for the production of fibers under optimal conditions which helps to maintain the integrity of the fibers, separate most of the encrusting components and increase the yield by up to 42%.

[0019] The use of water in this method is minimized: firstly, there is no traditional fiber cooking, which requires a lot of water; secondly, the processing of the raw material mainly uses steam, which saturates the biomass, so it becomes pourable, but not liquid; thirdly, the grinding process uses acetic acid, the lignin precipitates, and less water is needed to wash it. Thus, the water consumption is about 15 times less compared to the traditional technology field.

[0020] The claimed method comprises a minimum number of steps, requires a minimum number of equipment units, minimizes the number of steps for increasing and decreasing pulp consistency, minimizes the number of pulp washing steps required, and minimizes the number of pH changes. Furthermore, the method avoids the use of toxic substances or back-end chemicals. Instead, it is characterized by the use of mild alkalis and acids, i.e., non-toxic solvents, low cost, whereby all internal effluents can be restored. The claimed method is therefore environmentally friendly and cost-effective.

[0021] Preferably, the method according to the claims is characterized in that it produces a fibre pulp having the following characteristic values: grinding degree 28 °Schopper-Rigler degree (°RS), pH 8, fibre length 0.7-1.2 mm, fibre diameter 28-32 nm, brown kraft colour and ash content 11%.

[0022] The term "fibrous pulp" is used interchangeably herein with terms such as semi-fibrous pulp, fibrous semi-products and semi-cellulose.

[0023] Preferably, the non-wood plant material used comprises leaves of trees that fall in autumn, fallen leaves of bushes, fallen leaves of shrubs, leaf parts of temperate climate annual plants, leaf variants, such as needle-like leaf variants, and leaf stem parts of plants with a hard growing path, fresh plant leaves of waste nature, fallen leaves of tropical equatorial plants, i.e. fallen leaves of tropical equatorial trees, fallen leaves of tropical equatorial bushes, fallen leaves of tropical equatorial shrubs, leaf variants, such as water-storing leaves, thorns, etc., as well as leaf stem parts of plants with a hard growing path, fresh plant leaves of waste nature. The leaves may have any color scheme, structure, moisture, degree of contamination, degree of decomposition, size, origin and source of formation.

[0024] Preferably, separating the leaves comprises dividing the leaves into groups comprising at least a delicate group and a stable group.

[0025] The delicate group (LPG-001) refers mainly to temperate climate leaves, because they act mainly to maintain photosynthesis and gas exchange within a short period of the year (7 months). Their structure is very fragile, since they lack a rigid vegetative tissue that may contain fibers similar to those in the bast, for example. The technological processing process of these leaves therefore includes strong mechanical treatments and long alkaline treatments at very high temperatures to maintain the integrity of the fibers and the maximum pulp yield.

[0026] The majority of plants in the sensitive group (LPG-001) include the following temperate climate plants: Betula borysthenica Klokov, Betula pendula Roth., Ulmus minor, Fagus sylvatica L., Fagus orientalis, Ulmaceae, Salix L., Alnus incana, Aesculus hippocastanum, Carpinus betulus L., Quercus robur L., Quercus rubra, Quercus borealis, Catalpa bignonioides Walt., Castanea Sativa, Acer serrata ... platanoides L.(Norway Maple), Acer Campestre(Knob Maple), Tier platyphyllos(Summer Tree), Populus tremula L.(Aspen), Platanus L.(Square Tree), Populus nigra L.(Popwood), Fraxinus(Fash Tree), Prunus cerasus L.(Sweet Cherry), Juglans regia L.(Juglans regia), Morus(Mulberry), Pinus sylvestris L.(Scots Pine), Acacia(Acacia), Paulownia(Thorn Tree), Paulownia fortunei(Paulownia), Paulownia elongata(Parsley), Paulownia Cion in Vitro 112, Citrus sinensis(Orange), Citrus reticulata (Mandarin orange), Diospyros (Persimmon), Ficus (Fig), Acer saccharum Marsh. (Sugar maple), Vitaceae (Vitaceae), Humulus L., Ginkgo, Ginkgo biloba, Robinia pseudoacacia, Tectona grandis, Shorea robusta, Humulus L., Reynoutria japonica, Lycopersicon, Vitis, Juglans regia, Corylus avellana, Castanea, Castanea Sativa, Amelanchier, Malus, Rhus.

[0027] The strong group (SPG-002) refers mainly to leaves from tropical equatorial climates, because, taking into account the climatic conditions, especially the moisture regime and the long warm periods of the year, the fibers of these leaves have longer and more branched lignin fractions and a greater mechanical stiffness compared to leaves from temperate climates. To produce a fiber pulp, first the husks, lignin, xylan and other compounds must be removed from this group, which can be done under more aggressive pressure, temperature and alkalinity conditions (or, to produce a fiber pulp, first the husks, lignin, xylan and other compounds must be removed from this group, which can be done under more aggressive pressure, temperature and alkalinity conditions).

[0028] The majority of the stable plant group (SPG-002) includes the following tropical equatorial climate plants: Cocos nucifera, Roystonea altissima (Mill.) HEMoore, Roystonea borinquena OFCook, Roystonea dunlapiana PHAllen, Roystonea lenis Leon, Roystonea maisiana (LHBailey) Zona, Sabal. causiarum(OFCook) ex Becc., Sabal domingensis Becc., Sabal etonia Swingle ex Nash, Sabal gretherae HJQuero.R., Phoenix acaulis Roxb., Phoenix andamanensis S.Barrow, Phoenix atlantica A.Chev., Phoenix canariensis Chabaud, Phoenix dactylifera L. typus, Phoenix loureiroi Kunth, Phoenix paludosa, Bismarckia, Livistoneae, Ananas comosus var. bracteatus, Ananas comosus var. comosus (pineapple), Ananas comosus var. erectifolius, Aloe vera, Salacca zalacca.

[0029] The conditions of the claimed method are used for the treatment of both delicate and stable leaf groups.

[0030] Preferably, pre-preparation of the initial feedstock further comprises washing it and inactivating live microorganisms therein, followed by drying and shredding the separated feedstock.

[0031] The pressing of the chopped material preferably also includes its granulating (or granulating) or briquetting (or briquetting) or baling.

[0032] The chemithermomechanical fiber pulp may be subjected to grinding at high consistency and / or at low consistency.

[0033] Therewith, after the fiber pulp is crushed, it is subjected to vibration sorting to separate the non-defibrated particles of the pulp, followed by thickening of the pulp.

[0034] Furthermore, this object is achieved by providing an automated line for producing chemi-thermomechanical fiber pulp (hemi-thermomechanical / or chemi-thermomechanical) by the method according to the claims, the line comprising, arranged in series in the direction of movement of the raw material, an initial raw material pre-preparation unit, a chemi-thermomechanical unit and a grinding unit, The initial raw material pre-preparation unit at least includes a separation tool for separating the initial raw material from contents not containing plant fiber, a raw material shredder, and a raw material pressing tool; The chemi-thermomechanical unit includes at least a sealed thermomechanical screw disperser equipped with a pressurized steam supply tool, a high-pressure chemi-thermomechanical chamber configured to change the temperature and pressure and equipped with a supply tool for supplying an alkali metal hydroxide or a solution thereof in the form of an aerosol, and a high-concentration fiberization device; The grinding unit includes at least a high consistency hydropulper equipped with an acetic acid supply tool and at least one refiner; The outlet of the sealed thermomechanical screw disperser is connected to the inlet of a high pressure chemi-thermomechanical chamber, while the outlet of the high consistency fiberizer is connected to the inlet of a high consistency hydropulper.

[0035] The line is configured to carry out the claimed method for producing chemithermomechanical fiber pulp from non-wood raw materials, thereby providing all the advantages of the claimed method.

[0036] Preferably, the initial raw material pre-preparation unit further includes a washing tank equipped with a sterilizing solution supply tool and a dryer, the washing tank and the dryer are arranged in series and connected to each other, the outlet of the separation tool is connected to the washing tank, and the outlet of the dryer is connected to the shredder.

[0037] Furthermore, the chopped material pressing tool is preferably made as a granulator (or granulator / granulator), or as a briquetting press, or as a baling press.

[0038] According to one preferred embodiment, the grinding unit includes a high consistency refiner and a low consistency refiner arranged in series.

[0039] The comminution unit may further comprise a vibratory screening platform disposed after the refiner and comprising a water spray tool for spraying water onto the platform.

[0040] Additionally, the comminution unit may further include a pulp thickener located after the vibratory screening platform. [Brief description of the drawings]

[0041] The claimed invention is explained below with the aid of the following figures: [Figure 1] The figure shows a scheme of a preferred embodiment of an automated line for producing chemithermomechanical fiber pulp by the method of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0042] The figure shows a scheme of a preferred embodiment of an automated line for producing chemi-thermomechanical fiber pulp by the method of the present invention. Said line comprises three main units: an initial raw material pre-preparation unit 1, a chemi-thermomechanical unit 2, and a grinding unit 3. As can be seen from the figure, the pre-preparation unit comprises the following devices arranged in series and connected to each other: a raw material separation tool made as a drum separator 4, a washing tank 5, a convection tunnel dryer 6, a shredder 7, and a tool for pressing the raw material after the shredder made as a granulator 8. After passing through the granulator 8, the raw material is sent to a storage 9 or working hopper 10, from where it is fed to the chemi-thermomechanical unit 2. The chemi-thermomechanical unit comprises the following devices arranged in series and connected to each other: a screw mixer conveyor 11, a sealed thermomechanical screw disperser 12 with a pressurized steam supply tool, a high-pressure chemi-thermomechanical chamber 13, and a high-concentration fiberizer 14. The latter grinding unit 3 in turn comprises the following devices arranged in series and connected to each other: a high consistency hydropulper 15, two refiners 16 and 17, a vibrating screening platform 18, and a pulp thickener 19.

[0043] In order to study the parameters of the products that may be produced by the claimed method, as well as to illustrate the parameters of said method, the method was carried out under laboratory conditions as follows.

[0044] The leaf mixture was first separated from branches, debris, sand and dirt by washing under running water, then dried to a constant humidity and chopped. The weighed amount of the ram materials for process imitation was 1000 g.

[0045] The prepared dried leaves were loaded into a laboratory autoclave equipped with an electric heating element and kept at a pressure of 2 atmospheres (atm) and a controlled temperature of at least 100°C for 45 minutes using a 1:5 hydromodule. This process resulted in hydrothermal impregnation of the leaves, giving them plastic properties; that is, some temperature-labile molecules were transferred to a soluble phase, the resin became more injectable, while the proteins were denatured. This step was performed to prepare the raw material for impregnation with the alkaline solution.

[0046] The pre-prepared raw materials were passed multiple times (or multiply) through a laboratory rolling mill with slit sizes of 0.2-1 mm to crush / soften the raw materials and further prepare them for producing fibers.

[0047] The pulp was then washed and loaded into a non-hermetic screw mixer with heating capability up to 100°C, into which delignification alkaline solution was fed. The pulp was constantly stirred and rubbed by the high pressure generated when pumping the pulp in the direction of rotation of the screw shaft. This process lasted for 30 minutes. During this period, the soft, swollen raw material absorbed the active alkali, which resulted in it being partially delignified and thus liberating fibers suitable for paper production.

[0048] The delignified stock was loaded into a laboratory hydro rotor with a bottom rotor, where the stock at 8% pulp consistency was subjected to disintegration and partial fiberization for 5 minutes. Then, 3% acetic acid solution was added to the stock and the fiberization process continued for another 5 minutes. During this step, the integrated lignin precipitated and the fibers acquired properties that defined their further grinding and papermaking capabilities, the pH of the medium was 6, and the fibers were clearing.

[0049] The partially decomposed raw material, devoid of most of the lignin content, was washed and subjected to final defibration in a laboratory hollander according to the ISO 5264-1, TAPPI T 200m, T 205m, SCAN C 25 and CPPA C.2 standards. The average defibration time was 15 minutes, while the load on the rotor was applied by a 500g kettlebell. This mode made it possible to achieve a pulp grinding degree of 25°RS and to maintain the integrity of the fibers. The grinding was finished by washing, thickening and drying the fibers.

[0050] The obtained fiber samples were preliminarily dehydrated by pressing and drying in a drying cabinet at a temperature of 95°C (203°F) for 3 hours, and then they were analyzed.

[0051] Table 1 shows the results of the study of the component composition of the initial leaf mixture. Cellulose is the main component of the leaves and its content in some samples was measured at a level of 48.8%. The lignin content was 27%. This lignin / cellulose ratio is typical for annual plants. The initial swelling and softening of the pulp as well as the further alkaline chemi-thermomechanical treatment led to the destruction of the intermolecular ether bonds crosslinked by hemicellulose and lignin, which occurred gradually without damaging the fiber structure. Table 1: Study results of the composition of the initial leaf mixture TIFF2025509020000001.tif126169

[0052] Table 2 gives the results of the average fiber diameter obtained before and after chemithermomechanical treatment of the initial feedstock in various conditions, as well as in aggressive conditions of leaf treatment at high alkaline and acid concentrations, without steam treatment and rolling. After alkaline treatment, it was observed that the organic matter contained in the initial feedstock was actively dissolved, which started already at low temperatures when the feedstock was in contact with the alkaline solution. During the reaction, the solution was actively stained with brown color characteristic of lignin dissolution. Table 2 - Average diameter of produced fibres TIFF2025509020000002.tif244169

[0053] The vulnerability of such leaf fibre to processing conditions without prior preparation is related to the very loose structure of the leaf due to its high parenchyma content, which, when the leaf is saturated with water and performs its function, has a high degree of stiffness and elasticity. After falling, the water evaporates and the cellular structure becomes encrusted by lignin, which makes it compact and destructible. If alkaline solutions, mechanical forces or temperature suddenly act on this pulp, the internal pressure of the keratinized cells and interstructural elements breaks in an uneven way, leading to the breakage of the fibre together with the outer skin.

[0054] Several treatment options for the leaves have been defined, depending on whether they relate to a sensitive or stable group, and these treatment options are provided below.

[0055] Example 1. Pre-prepared raw materials of the delicate group were treated with an alkali concentration of 3% for 2 hours at a temperature of 70°C-80°C according to the method described in the patent.

[0056] Example 2. Pre-prepared raw materials of the delicate group were treated with an alkali concentration of 3% for 2 hours at a temperature of 75°C to 85°C according to the method described in the patent.

[0057] Example 3. Pre-prepared raw materials of the delicate group were treated with an alkali concentration of 3% for 2 hours at a temperature of 90°C-100°C according to the method described in the patent.

[0058] Example 4. Pre-prepared raw materials of the delicate group were treated with an alkali concentration of 2% for 2 hours at a temperature of 70°C-80°C according to the method described in the patent.

[0059] Example 5. Pre-prepared raw materials of the delicate group were treated with an alkali concentration of 2% for 2 hours at a temperature of 75°C to 85°C according to the method described in the patent.

[0060] Example 6. Pre-prepared raw materials of the delicate group were treated with an alkali concentration of 2% for 2 hours at a temperature of 90°C-100°C according to the method described in the patent.

[0061] Example 7. Pre-prepared raw materials of the delicate group were treated with an alkali concentration of 1% for 3 hours at a temperature of 70°C-80°C according to the method described in the patent.

[0062] Example 8. Pre-prepared raw materials of the delicate group were treated with an alkali concentration of 1% for 3 hours at a temperature of 75°C to 85°C according to the method described in the patent.

[0063] Example 9. Pre-prepared raw materials of the delicate group were treated with an alkali concentration of 1% at a temperature of 90°C-100°C for 3 hours according to the method described in the patent.

[0064] Example 10. The pre-prepared material of the delicate group was treated according to the claimed method for 1.5 hours at a temperature of 110° C., an alkali concentration of 3% and a pressure of 3.5 atm.

[0065] Example 11. The pre-prepared material of the delicate group was treated according to the claimed method for 1.5 hours at a temperature of 120° C., an alkali concentration of 3% and a pressure of 4.5 atm.

[0066] Example 12. Pre-prepared materials of the delicate group were treated according to the claimed method at a temperature of 110° C. for 2 hours, with an alkali concentration pf 2% and a pressure of 3.5 atm.

[0067] Example 13. Pre-prepared raw materials of the delicate group were treated according to the claimed method at a temperature of 120° C. for 2 hours, with an alkali concentration pf 2% and a pressure of 4.5 atm.

[0068] Example 14. Pre-prepared materials of the delicate group were treated according to the claimed method at a temperature of 110° C. for 2 hours, with an alkali concentration of 1% and a pressure of 3.5 atm.

[0069] Example 15. Pre-prepared materials of the delicate group were treated according to the claimed method at a temperature of 120° C. for 2 hours, with an alkali concentration of 1% and a pressure of 4.5 atm.

[0070] Example 16. Pre-prepared raw material of the delicate group was processed by soaking the leaves in hot water and mechanically rolling the softened pulp, while cold extraction of the fibres was carried out with an alkaline concentration of 1% for 2 h.

[0071] Example 17. The delicate group leaf mixture was treated by soaking the leaves in hot water and mechanically rolling the softened pulp, while cold extraction of the fibres was carried out with an alkaline concentration of 2% for 2 h.

[0072] Example 18. Pre-prepared raw material of the delicate group was processed by soaking the leaves in hot water and mechanically rolling the softened pulp, while cold extraction of the fibres was carried out with an alkaline concentration of 3% for 2 h.

[0073] Example 19. The pre-prepared raw material of the stable group was treated with an alkali concentration of 3% at a temperature of 70°C-80°C for 2 hours according to the method described in the claims.

[0074] Example 20. The pre-prepared raw material of the stable group was treated with an alkali concentration of 3% at a temperature of 75°C to 85°C for 2 hours according to the method described in the claims.

[0075] Example 21. The pre-prepared raw material of the stable group was treated with an alkali concentration of 3% at a temperature of 90°C-100°C for 2 hours according to the method described in the claims.

[0076] Example 22. The pre-prepared raw material of the stable group was treated with an alkali concentration of 2% at a temperature of 70°C-80°C for 2 hours according to the method described in the claims.

[0077] Example 23. The pre-prepared raw material of the stable group was treated with an alkali concentration of 2% at a temperature of 75°C to 85°C for 2 hours according to the method described in the claims.

[0078] Example 24. The pre-prepared raw material of the stable group was treated with an alkali concentration of 2% at a temperature of 90°C-100°C for 2 hours according to the method described in the claims.

[0079] Example 25. The pre-prepared raw material of the stable group was treated with an alkali concentration of 1% at a temperature of 70°C-80°C for 3 hours according to the method described in the claims.

[0080] Example 26. The pre-prepared raw material of the stable group was treated with an alkali concentration of 1% at a temperature of 75°C to 85°C for 3 hours according to the method described in the claims.

[0081] Example 27. The pre-prepared raw material of the stable group was treated with an alkali concentration of 1% at a temperature of 90°C-100°C for 3 hours according to the method described in the claims.

[0082] Example 28. The pre-prepared stock of the stable group was treated according to the claimed method for 1.5 hours at a temperature of 110° C., an alkali concentration of 3% and a pressure of 3.5 atm.

[0083] Example 29. The pre-prepared material of the stable group was treated according to the claimed method for 1.5 hours at a temperature of 120° C., an alkali concentration of 3% and a pressure of 4.5 atm.

[0084] Example 30. The pre-prepared material of the stable group was treated according to the claimed method at a temperature of 110° C. for 2 hours, an alkali concentration of 2% and a pressure of 3.5 atm.

[0085] Example 31. The pre-prepared material of the stable group was treated according to the claimed method at a temperature of 110° C. for 2 hours, at an alkali concentration of 1% and at a pressure of 3.5 atm.

[0086] Example 32. The pre-prepared material of the stable group was treated according to the claimed method at a temperature of 120° C. for 2 hours, at an alkali concentration of 1% and at a pressure of 4.5 atm.

[0087] To establish the quality of the produced fibers, several papermaking tests were carried out and the paper was analyzed to evaluate its physical and mechanical parameters.

[0088] Paper samples made from 100% fiber and mixed in various ratios with MS-5B brand recycled paper were cast from the fiber produced by the above method. Casting was performed on a D-47809 paper machine with an inclined 36.4 cm wide grid table and an open headbox at a rolling speed of 2.15 m per minute.

[0089] After the samples were cast, dried and cut, the papers were tested to evaluate their physical and mechanical parameters.

[0090] Table 4 shows the results of the paper product tests, i.e. for papers made with the fallen leaf mixture and for papers made with the same mixture and MS-5B brand recycled paper. The tests were carried out according to the following standard: BDS EN ISO 536:2020 Paper and board - Paper 1m 2 (ISO 536:2019), BDS EN ISO 534:2012 Paper and paperboard-Determination of thickness, density and specific volume (ISO 534:2011), B ISO 535:2014 Paper and paperboard-Determination of bursting strength (ISO 2758:2014), ISO 1974:2012 Paper-Determination of tear strength-Elmendorf method, BDS ISO 1924-3:2011 Paper and paperboard-Constant elongation method (100mm / min), ISO 5636-5:2013 Paper and paperboard air permeability (intermediate range)-Part 5: Gurley method. Table 4. Physical and mechanical parameters of paper TIFF2025509020000003.tif254169

[0091] According to the test results of the paper laboratory samples shown in Table 3, it can be concluded that the physical and mechanical parameters of paper made from 100% plant bio-waste are satisfactory.

[0092] When the pulp grinding degree is 28°RS, 98g / m 2 1m of paper 2 A weight of 0.01 mm and a thickness of 0.35 mm are achieved, which is higher than the standard. Possibly, this can be caused by the high dimensions of the fibers. The breaking force in the machine direction in the dry state is 21% lower than the standard average value, while the breaking force in the transverse direction is in line with the standard. The bursting strength index is higher than the standard. The air permeability of the paper is higher than the standard because the fibers have a low degree of crushing. It is noted that in order to provide the test purity, all test paper samples were not sized, i.e. all parameters can be significantly improved by supplementing the paper pulp with fillers that improve the mechanical properties of the paper, such as alkyl ketene dimer (AKD) or starch.

[0093] Technological processes simulated under laboratory conditions confirmed that it is possible to use plant-based organic materials of non-wood origin for the manufacture of paper products with satisfactory parameters.

[0094] The claimed line operates as follows.

[0095] The leaves are pretreated by an initial feedstock pre-preparation unit 1 according to the scheme (see figure). The leaves fed to the facility landfill are fed to a drum separator 4 where they are purged with an air flow through perforations, thereby removing sand, stones, heavy non-plant contents or light fractions, e.g. polyethylene. The drum separator 4 is equipped with internal ribs and is arranged at an angle, so that when rotating clockwise, the leaves move towards the upper section of the separator 4 and are thereby unloaded into the washing tank 5. The tank 5 is filled with a germicidal liquid for inactivating live microorganisms. Water circulation and air bubble type agitation move the leaves towards the front of the tank 5, where they are captured by a grid vibrating conveyor that moves them through an air dehydrator and then through a convection tunnel dryer 6. The leaves may be transported both in dry and wet state, but in any case they must be washed to remove dirt, bacteria and fungal spores as well as dried to allow long-term storage. After the leaves have been dried, they are chopped by a shredder 7 to obtain a particle size of 1-2 cm. The chopped leaf mass is poured into a collection hopper, from where it is fed by a screw conveyor to the granulator 8. As leaves have a low bulk density, the granulation process makes it possible to increase this parameter. Depending on the type of raw material, cylindrical granules with a diameter of 1 cm and a length of 2 cm, or briquettes with dimensions 2 x 2 cm, may be produced. Then, depending on the production needs, a redistribution is carried out, so that one part is packed in a big-bag container, while another part is loaded by a screw conveyor into the next unit.

[0096] This step is performed to obtain a maximally selective feedstock for cost-effective storage, transportation, and further processing.

[0097] The dry granulated leaf mass is fed through a screw mixer conveyor 11 to a sealed thermomechanical screw disperser 12. The screw disperser is made as a cylindrical horizontal chamber with a screw shaft with a smaller pitch towards the unloading of the mass, so that the mass is at very high pressure during its output and is therefore prone to friction. Pressurized water vapor is fed to the disperser at high temperature. The main purpose of this step is to give the leaves elasticity, swelling and more homogeneity. This process is provided in a moist medium and at high temperature so that some of the organic molecules dissolve, proteins denature etc., making the leaves easier to further process.

[0098] After being extruded by pressure and rotary movement, the plasticized soft leaves are sent to a chemi-thermomechanical chamber 13 under high pressure conditions. Sodium hydroxide aerosol is fed into said chamber, the leaves are vigorously stirred and saturated with alkali, thereby resulting in the decomposition of most compounds and the transfer of lignin to a soluble phase. Due to the formation of condensates, the pulp, already semi-fibrous, is thoroughly washed to remove lignin. The alkali in the form of aerosol is fed into the chamber through a nozzle, the pH of the process is about 12, the active alkali concentration is 3%, the hydromodule is 1:3, the operating temperature is 105-120 °C and the pressure is 3.5-4.5 atm.

[0099] According to the same working principle of the thermomechanical screw disperser, the raw material is unloaded into the high-concentration fiberizer 14, which refines the fibers by cutting the cellulose fibrils. Due to the strong plasticity of the biomass and the lack of husks in it, the fibers are not as breakable as before and are easier to cut.

[0100] This process is carried out to produce a high yield fiber pulp that is easy to grind.

[0101] This crushing is carried out by unit 3, as shown in the figure. As the fibre size decreases with the flow of water, the already fibrous pulp passes through the grinding discs of the high consistency defibrator 14 and is pumped to the high consistency hydropulper 15, which is supplied with a 3% acetic acid solution. The purpose of this step is to precipitate the integral lignin, adjust the pH value and compress the cellulose fibrils. Beating is carried out for 15 minutes, after which the fibre pulp is poured by its own weight into a basin from where it is distributed between the primary and secondary refiners 16 and 17, respectively. At this step the pulp crushing degree is already between 15 and 22°RS. As the leaves have a very brittle structure, the crushing mode in the refiner can be carried out in several ways, namely: - Both refiners are involved, the first refiner produces a higher concentration, while the second refiner produces a lower concentration, - Only one refiner involved, high consistency, short grinding time, - Only one refiner involved, low consistency, short grinding time, -Only one refiner is involved, low consistency, long grinding time.

[0102] Refiners 16 and 17 allow adjustment of the degree of joint closure which affects the time the pulp passes through the refiner, which also affects the degree of further grinding. The optimum degree of grinding in this method is 28° RS.

[0103] Since some particles may be present in the biomass that were not cut into fibers in the previous steps, after every production step screening on a vibrating screening platform 17 is performed by spraying with water to provide a better separation of the fibers from the non-fiber content. By performing the screening step at this particular point in time, rather than after the alkaline treatment step, raw material losses are reduced.

[0104] Nevertheless, the screening can be carried out in several steps depending on the raw material and the quality and economic requirements. After the screening is carried out, the 100% fiber pulp is fed to a pulp thickener 19 for its subsequent distribution to paper product manufacturing facilities.

[0105] According to test results, the method is characterized by the following values ​​of resource consumption for producing 1 ton of pulp: Table No.5-Resource consumption to produce 1 ton of pulp TIFF2025509020000004.tif85169

[0106] The chemithermomechanical fiber pulp produced is used, for example, in paper products, in particular in calendered kraft paper (70-170 g / m 2 ), non-calendared kraft paper (70~420g / m 2 ), paper bags, multi-layer corrugated board, corrugated board with 3, 5, 8 layers which are subsequently processed into corrugated packaging, egg carton-type cast packaging produced by vacuum casting method, egg boxes, logistics packaging, floor insulation lining (2.5-10mm), bulk insulation, seedling and plant packaging, decorative materials and fillers, fiber polymer foams, biocomposite fiber-based materials produced from leaves and bioplastics, bio polyurethanes.

[0107] Thus, methods and automated lines for producing chemi-thermomechanical fiber pulp from various kinds of non-wood plant raw materials (sensitive and stable group raw materials) are provided, which are intended to achieve the technical effect of producing chemi-thermomechanical fiber pulp suitable for producing specific purpose paper products, with maximum performance and minimum cost, in an environmentally friendly manner.

Claims

1. 1. A method for producing a chemithermomechanical fiber pulp from a non-wood plant material, the method comprising: - a step of pre-preparing the leaves, said step comprising at least separating said leaves from non-fiber-containing contents and shredding said separated material; chemi-thermomechanical processing of the preconditioned feedstock, the process including at least plasticizing, softening, and delignifying the plasticized feedstock to produce a semi-fibrous, partially delignified pulp; and grinding the semi-fibrous, partially delignified pulp to produce a chemi-thermomechanical fiber pulp. The pre-preparation of the initial feedstock further comprises pressing the shredded leaves; said plasticization and softening of said pre-prepared leaves is carried out by mechanical rubbing thereof and by treatment with pressurized heated steam, said delignification of the plasticized soft feedstock is carried out by pressurized mixing thereof in the form of a solution or aerosol having an alkali concentration of up to 3% or in the presence of an alkali metal hydroxide at a temperature of 70-120° C. and at a pressure of at least 3.5 atm; The method, wherein the grinding is carried out in the presence of acetic acid at a concentration of up to 3%.

2. The method of claim 1 , wherein said separating the leaves comprises dividing the leaves into groups comprising at least a delicate group and a stable group.

3. 10. The method of claim 1, wherein said pre-preparation of said initial feedstock further comprises washing said feedstock and inactivating live microorganisms therein followed by drying and shredding said separated feedstock.

4. The method of claim 1 , wherein the pressing of the chopped raw material comprises granulating or briquetting or baling thereof.

5. The method of claim 1 , wherein the chemi-thermomechanical fiber pulp is ground at high consistency and / or low consistency.

6. The method according to claim 1 , further comprising the steps of: crushing the fiber pulp, followed by vibratory screening to separate undefibrated particles of the pulp, and then thickening the pulp.

7. 13. An automated line for producing chemithermomechanical pulp by the method of claim 1, the lines being arranged in series in the direction of movement of the raw material, An initial raw material pre-preparation unit; Chemi-thermomechanical unit, Crushing Unit The components of The initial raw material pre-preparation unit includes at least: a separation tool for separating the initial feedstock from non-fiber-containing content; A raw material shredder; A raw material press tool, The chemi-thermomechanical unit comprises at least a sealed thermomechanical screw disperser equipped with a pressurized steam supply tool; a high pressure chemi-thermomechanical chamber configured to vary temperature and pressure, the high pressure chemi-thermomechanical chamber being provided with a delivery tool for delivering an alkali metal hydroxide or a solution thereof in the form of an aerosol; A high-concentration defibration device, The grinding unit comprises at least A high consistency hydropulper equipped with an acetic acid supply tool; at least one refiner, The outlet of the sealed thermomechanical screw disperser is connected to the inlet of the high pressure chemi-thermomechanical chamber, while An automated line, in which the outlet of the high consistency defibrator is connected to the inlet of the high consistency hydropulper.

8. 8. The line according to claim 7, wherein the initial raw material pre-preparation unit further includes a washing tank having a sterilizing liquid supplying tool and a dryer, the washing tank and the dryer are arranged in series and connected to each other, an outlet of the separation tool is connected to the washing tank, and an outlet of the dryer is connected to the shredder.

9. 8. The line according to claim 7, wherein the chopped material press tool is made as a granulator or as a briquetting press or as a baling press.

10. 8. The line of claim 7, wherein the grinding unit comprises a high consistency refiner and a low consistency refiner arranged in series.

11. 8. The line of claim 7, wherein the grinding unit further comprises a vibratory screening platform disposed after the refiner, the vibratory screening platform comprising a water spray tool for spraying water onto the platform.

12. The line of claim 7 , wherein the comminuting unit further comprises a pulp thickener disposed after the vibratory screening platform.

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