EP2300221B1 - Method for pulping lignocellulose into fibre materials - Google Patents

Description

The invention relates to a process for the digestion of lignocellulosic materials into fibrous materials and to a process for the further processing of these fibrous materials.

Before being processed, lignocelluloses are comminuted to produce and insulation materials, to reinforcements or fillers, to cardboard or to fuels, either to chips or to fibrous materials. The thin and mostly curved fibers gain in increasing economic importance compared to the straight, stiff and highly elastic chips, because they have better processing properties and the products made with them are superior.

The most important machines for defibering the lignocelluloses are grinding stones, twin-screw extruders and cone or disc refiners. Currently dominate the double disc refiners. In the case of the double-disc refiner, the fiberizing disruption is mainly due to shearing stress between the two grinding discs arranged in parallel and profiled on the inside with ribs, one of which is arranged rigidly and the other rotates at high speed. In the digestion process, the lignocelluloses flow as an aqueous-flowable mass after the radial Entry into the refiner through the increasingly narrowing gap between the grinding discs to the outside. The lignocelluloses are split by shear forces successively to fibers with high to very high fineness.

Important disadvantages of the named Zerfaserungsmaschinen are low throughput and / or high electrical energy requirements. The currently dominant refiner also has the disadvantage that the defibration of harder lignocelluloses such. As wood, is only possible if the raw material is previously hydrothermally softened by a cooking process at high pressures of about 10 to 20 bar and temperatures of about 160 to 220 ° C. This requires expensive apparatus technology and a lot of heat energy. Furthermore fall in the necessary dewatering of Faserpülpe large amounts of polluted wastewater.

The decomposition of lignocelluloses with refiners results in fibrous materials that are poorly refined internally because the defibration process is mainly due to shear stress. The high porosity in the fibers is therefore largely retained. In addition, admixed substances such. As binder and / or water repellent, distributed mainly on the surface of the fibers. The pore volume of the fibers contains gases after the water has dried. The pores in the fibers reduce the strength of the fibers, and they degrade the compression properties of the pulp z. As in the production of fiber materials by compression molding, because the trapped in the pores gases increase the compression resistance and reinforce the re-expansion after the pressure relief of the pressed material. The latter can even lead to the destruction of the material by expansion cracks.

The document DE-B-1074390 discloses a method for digesting lignocellulosic materials into pulps using pug mill rolls after blending and treatment with chemicals.

The pore volume also favors the damage of the products by the penetration of water and / or microorganisms.

The object of the invention is in the context of the production of new lignocellulose-based materials to provide a method for digesting these lignocelluloses with improved and also flexibly adjustable properties, which is characterized by a small number of process stages and low heat and electrical energy requirements and in which no heavy burden Wastewater from a cooking process incurred.

According to the invention the object is achieved by the features of claim 1.

By "fiber improvers" is meant here substances which not only promote broadening and comminution of the material, but are reactive substances which impart new, significantly improved properties to the fibers with a view to their further use as materials. They have a modifying, changing, ennobling effect. The refining of the fibers takes place during the exclusion in the pellet press and above all during drying and / or storage.

By "wet surface state" is meant a state in which the water content is about 5 to 15% higher than the saturation water content. This, in turn, indicates the moisture content that a raw material has when its inner pore volume is completely filled with water, but there is no additional surface moisture. All brown coal from different opencast mines or from different seams in an opencast mine, every type of wood or straw and also the same wood of different ages each have their "saturation water content" depending on the material and pore structure. That's why this size is resource-specific. These saturation moisture contents are a minimum requirement for the formation of high quality pulps in the pellet press. In the reduction of partially or strongly pre-dried lignocelluloses with pellet presses, a "spanish" comminution product is always produced.

This is also the case with a previously known method ( EP 0 143 415 ). There, namely, the crushed product is processed immediately after crushing in a first pellet press in another pellet press pellets, which requires that the material from the beginning can have only a very low humidity, otherwise in the holes of the die of the second pellet press no Pressure can be built up, which is required for the production of at least semi-solid pellets. In addition, if too high a water content due to the heating in the second pellet press this would abruptly when exiting the press channels, where high pressure prevails evaporate, causing unacceptable cracks in the pellets and causing them to easily disintegrate or, in particular, to crumble upon further handling. The aim of this prior art method is also fundamentally different from the method according to the invention, by which neither comminution of the lumpy long-fiber material causes still pellets to be produced, but a fibrous material to be produced with novel properties.

Also in another known method ( DE 199 55 844 A1 ) are to be produced in contrast to the method according to the invention pellets of pressed biomass. In order to be able to produce these pellets, a wood moisture content of 11 - 14% is absolutely necessary. In contrast, in the process according to the invention with significantly greater humidity, namely the surface moist condition mentioned, worked, ie a state where not only the pores are completely filled with water - this would correspond to a humidity of up to 50 wt .-% - but In addition, working with an excess moisture of 5 to 15% water, which is present as surface moisture. As an additive in the previously known method, no fiber improving material having the above-mentioned properties is used, but corn starch, by which the pressing pressure is lowered, the sliding effect is increased and binder properties are obtained. By contrast, the properties of the fibers are changed by the fiber-improving agents used according to the invention, since the fiber-improving substances penetrate into the fibers and thus modify them. This penetration is caused not only by the mechanical processing, but also by the higher humidity, so that wet-chemical reactions can take place, which is not possible with the previously known pellets because of the low moisture content of only 11-14%. Furthermore, one must work in the production of pellets made of wood with very small size of the press nip (distance of the pusher rolls from the die), namely to 0.2 mm. In the method according to the invention, however, larger distances up to 2 mm or even up to 5 mm and thus lower rolling pressures are possible.

For the digestion process, flat die pellet presses are used, in which a high and specifically variable pre-pressure can be set on the press rolls. This can be effected for example by adjustable compression springs or with a hydraulic system. The flat die pelleting press is advantageously suitable for the defibering process, because the pressing force in the narrowest gap between the flat die and the press roll is concentrated on a very small line surface, the so-called press seam. This allows, by the form, e.g. reinforced with the hydraulic system, the setting of particularly high and at the same time selectively variable specific compressive pressures in the squeeze seam. The high compressive stress of the material in the narrow pressure seam between a flat surface and the rounded surface of the press roller causes a concertina-like spreading of lignocelluloses to individual fiber bundles, because in the lignocellulosic the tensile strength perpendicular to the fiber direction is substantially lower than in the fiber direction and the pressed material in which can dodge both sides of the squeeze expanding pressing chambers.

The feed material must have the state of a surface-moist solid mixture, because the lignocelluloses soften due to the high water content, which is the splitting process allows for fiber bundles. The surface-moist state is also necessary because the lignocelluloses only then have the necessary compressive plasticity, which is necessary for a lateral squeezing out of the substance from the press nip and thus enables dissolution into individual fiber bundles in the first place. If the lignocelluloses are too dry, then they are completely drawn without alternate flow in the narrowest press nip, embrittled there by high pressure compression and discharged as a solid film or in the form of chip-shaped material. On the other hand, the feed material must not be too moist, because otherwise it assumes the property of a solid dispersed in water under pressure and escapes any press compaction in the press nip between the flat die and the Kollerwalzen by premature flow away. The feed would then drain without precompaction and without splitting into fiber bundles quickly through the holes of the flat die.

The flat die pelleting press is also advantageously suitable for the production of high-quality fibrous materials from lignocelluloses, because the feedstock is compacted not only with relatively high, but selectively adjustable specific pressing pressures in the narrowest press nip, but the pulping process is realized by a rolling load stress rolling over the material several times , This allows the production of highly compacted low-pore fibers without weakening by local overpressing of the solid, because the compression process is realized by the multiple rolling over of the goods by the press rolls successively and thus gentler.

Due to the multiple Wälzdruckbeanspruchung of the feed with high, but specifically adjustable specific pressing pressures is also achieved that the admixed fiber improvers are pressed under the moist-pasty environment conditions successively in the inner pore volume of increasingly thinning fiber bundles and succeeds largely continuous mixing to the fiber center.

The flat die pelleting press has the advantage over the ring die pelleting press that the roll rollers can not roll on the flat die without friction, since a relative movement between the roll surface and the flat die press takes place in a direction close to the axis, which is the direction of the relative movement in the edge region of the flat die press is opposite.

The type of fiber-improving substances depends on the field of application of the fibers to be produced and the properties to be fulfilled. Suitable fiber-improving substances are substances which ultimately impart the desired properties during the pulping process in the flat-matrix pelleting press and / or thereafter to the fibers by physical and / or chemical reactions and by partial filling of internal pore volume. The fiber improvers may be solutions, liquids and / or dispersed solids. The quality-forming reactions take place between the resulting pulp and the fiber improvers or some ingredients of both substances as well as partially in the fiber improvers itself. The required intensity and the depth effect of the reactions in the fibers is only by the common digestion of lignocelluloses and Fiber upgrading in the flat die pelleting press under conditions of prolonged intense Wälzdruckbeanspruchung and required for the reactions aqueous environment achieved.

For the implementation of the digestion process in the flat-matrix pellet press increased Guttemperaturen not process-related necessary, but beneficial. As the product temperature rises, the pulping and impregnation processes of the fibers are facilitated and the accumulated reactions intensified.

The flat-matrix pellet presses are therefore also advantageous for the digestion of lignocelluloses to high-quality fibrous materials with flexibly adjustable properties, because part of the active digestion organs consists of a flat die with a large number of holes whose opening width, shape and distance can be selected within large ranges , Due to the large number of holes in the flat disc, high throughput rates are possible. Furthermore, damage to the fibers by mechanical overstress is avoided by the hole openings, because the fibers are discharged after reaching the required fineness through the hole openings. The timely discharge is made possible by the high plasticity of the surface moist pulping material. The hole openings are designed so that their on resistance prevents too fast discharge of the material from the digestion space and at the same time a mechanical overuse of the fibers is avoided by too slow discharge. The distance between the holes, the format, the aperture size of the holes, and the die thickness can increase the intensity of the digestion and reaction process be adjusted so that the given fiber quality is achieved. The holes in the flat die are an important reason why the pulp can be opened up without the risk of overstraining with the high specific pressing pressures in the press seams. Their opening width may be between about 2 to about 15 mm, depending on the desired fiber quality. Furthermore, the length and the geometry of the hole channels are to be designed so that no high displacement resistance, which would lead to pelletization occur. The digestion material is discharged as a moist bonded brittle mass.

The pulp is always discharged primarily through the holes of the flat die. A further increase in the throughput capacity of the digestion machine is possible by a supplementary discharge of a portion of the pulping material via an obliquely placed edge rifle.

With flat-matrix pellet presses, therefore, an intensive digestion of the lignocelluloses is achieved at the same time with high throughput, because the press rolls or pug rollers move at high speed of about 2.1-2.6 m / sec in the middle circular path and the presses in dependence Their size with 2 to 5 press rollers are equipped. Furthermore, the largest presses have a large active die area of about 6,000 cm ² .

The flat die pelleting press is also advantageous for the pulping process because it allows the press rolls to be directly driven. In this way it is ensured that the feed material is digested by the required rolling overrolling stress. For press rolls without direct drive, such as z. As with ring die presses, there is a risk that the roller without slippage slide without self-rotation over the moist good without genuine fiberizing effect.

The most important reasons for the high quality of the produced fibers and for the flexibly adjustable properties are the strong reduction of the pore volume in the fibers as well as the modifying effect of the fiber improvers. The type of fiber improver depends on the field of application of the fibers. The number of suitable substances is therefore very large. As fiber improvers z. B. lignite, black peat, water-milled cement-slaked lime, gypsum and / or ash, acids, salt solutions, pitches, bitumens, waxes, resins, glues and a large number of starch, sugar and / or protein-rich natural substances suitable ,

The pulp is discharged from the flat pellet pellet press as a more or less strongly bonded product with a high water content. The Austragsgut can z. B. as a pulp for the production of silage, as pre-digested feed or for the production of fiber materials by the wet hot pressing process can be used directly. In other applications, an aftertreatment by drying and / or by loosening comminution is required. Drying sets the final water content required for further processing of the pulp. Furthermore, many important reactions between the pulp and the fiber improvers and / or in the fiber pulp are initiated or enhanced and completed by the heating of the material during drying and by the removal of water. Due to the loosening acting comminution are adhesive bonds, Zwickelbrücken and positive connections between the fibers dissolved. During the drying of the material treated according to the invention, the advantage arises that, for example, wood dries faster after the mechanical treatment, since the water is no longer enclosed in cells.

For the loosening acting post-shredding z. As mechanical vortex mixers, disc mills, pin mills, disc mills and racquets with one or two rotors suitable. For drying z. B. Convection dryer with mechanical loosening elements best.

By the digestion process described high-quality fibers with flexibly adjustable properties such. High binding rate, high drying rate, improved digestion properties, high water resistance, optional high resistance to biodegradation or acceleration of microbiological conversion reactions, high mixing stability, improved compression properties by reduction of compression resistance and reduction of elastic reexpansion after press release, conversion of hydrophilic to hydrophobic Fabrics, high structural strength, low glue requirement, increased soil fertility, u. a. m. From the fibers z. B. even then high-quality fiber materials are produced when the fineness of the fibers is lower than in the use of conventional Refinerfaserstoffen.

The new digestion process for the production of fibrous materials from lignocelluloses is in addition to the already mentioned advantages compared to the other defibration processes by low electrical energy requirement of ≤50%, low need for heat energy, small number of process stages and by no accumulation of polluted wastewater by eliminating the pressure boiling before the digestion process.

Further advantages of the method are the robustness of the flat-matrix pellet press against hard foreign substances. The machine wear is low, because at the Good stress by rotating press rollers, the wear by friction is low. The foreign matter is either crushed or discharged by the press rolls, because the press rolls dodge upwards when overloaded. The process is suitable for the production of fibrous materials from recent and / or fossil lignocelluloses in the form of lignite xylitol or pulp.

The addition and mixing of the lignocelluloses or the lignocellulosic materials with the appropriate fiber improvers can take place in the form of solutions, liquids and / or dispersed solids in the weight ratio dependent on the application of the pulp and a water supply, so that a total of a wet surface mix arises.

The refining effect of the fiber improvers can be realized by physical and / or chemical reactions between the newly formed fibers and the fiber improver or between ingredients of both feeds, by reactions in the fiber enhancers and by the partial filling of pore volumes in the fibers.

By the flexible adjustment of digestion conditions and by the nature and the proportion of fiber improvers high quality fibers with the required properties such. B. improved drying and / or digestion and / or binding and / or compression properties and / or produced with high mixing stability and / or as needed with high resistance to biodegradation or with improved properties for rapid microbiological conversion reactions.

Advantageously, a pellet press is used, in which the rolling rollers not only roll on the die, but are provided with its own drive. This can be done via the drive of the rotary motion (king shaft) or via its own drive motors.

The discharge of the material to be pulped from the flat pelletizing pellet press can be done in an advantageous embodiment, not only through the holes in the die, but also over the edge of the flat die press, which is expediently provided there with an edge guard.

As a flat die such is selected with a depending on the quality of fiber to be achieved hole geometry in terms of size, opening width, hole spacing and Lochkanallängsgeometrie and with a die thickness that allows intensive Wälzdruckverdichtung without damaging the fibers, high flow rates and Gutaustrag in the loose state without formation of solid pellets

1. a) 5 bis 60 Gew.-% Weichbraunkohlen mit lagerstättenabhängigen Sättigungswassergehalten von 50 bis 60 %
2. b) 10 bis 40 Gew.-% Zement (trocken) nach Befeuchtung zu Mörtel
3. c) 1 bis 40 Gew.-% Löschkalk (trocken) nach Befeuchtung zu Mörtel
4. d) 5 bis 40 Gew.-% Gips (trocken) nach Befeuchtung zu Mörtel
5. e) 5 bis 50 Gew.-% Kraftwerksfilteraschen (trocken) nach Nassaufschlussmahlung zu einer Mörtelmasse
6. f) 5 bis 60 Gew.-% Magerquark oder quarkreiche Veredlungsprodukte
7. g) 5 bis 25 Gew.-% eiweißreiche Extraktionsschrote von Ölsaaten (trocken) nach Nassaufschlussvermahlung zu einer feindispersen Masse und/oder durch Kochen der breiigen Masse
8. h) 3 bis 15 % Gew.-% Stärke bzw. stärkereiche Rohstoffe (trocken) nach Aufschluss zu Kleistern oder nach Dünnkochung
9. i) 1 bis 15 % Gew.-% Zucker oder zuckerreiche Rohstoffe nach Auflösung
10. j) 1 bis 15 Gew.-% natürliche oder synthetische Leime
11. k) 0,5 bis 10 Gew.-% Paraffine und/oder Bitumina, Peche, Wachse, Harze nach ihrer Verflüssigung
12. l) Feinkörnige oder flüssige Nährstoffe, Mineralsalze und/oder Vitamine in Art und Menge nach dem Bedarf des Anwendungsfalles
13. m) Salz zur Herstellung von Faserstoffen für Silagen
14. n) 1 bis 20 Gew.-% Säuren und/oder Salze mit konservierender Wirkung
15. o) Düngestoffe hinsichtlich Anteil und Art nach Bedarf des Einsatzgebietes
16. p) Ton- und Lehmmineralien in vom Anwendungsfall abhängigen Anteilen.

The fiber-improving agents are advantageously selected one or more at a time from the following materials:

1. a) 5 to 60% by weight of lignite coal with deposit-dependent saturation water contents of 50 to 60%
2. b) 10 to 40 wt .-% cement (dry) after moistening to mortar
3. c) 1 to 40 wt .-% slaked lime (dry) after moistening to mortar
4. d) 5 to 40 wt .-% gypsum (dry) after moistening to mortar
5. e) 5 to 50 wt .-% power plant filter ash (dry) after wet pulping to a mortar mass
6. f) 5 to 60% by weight of lean quark or quark rich processing products
7. g) 5 to 25 wt .-% protein-rich extraction meal of oil seeds (dry) after wet digestion to a finely dispersed mass and / or by boiling the pulpy mass
8. h) from 3 to 15% by weight of starch or high-starch raw materials (dry) after digestion into pastes or after thin-boiling
9. i) 1 to 15% by weight of sugar or sugar-rich raw materials after dissolution
10. j) 1 to 15 wt .-% natural or synthetic glues
11. k) 0.5 to 10 wt .-% paraffins and / or bitumens, pitches, waxes, resins after their liquefaction
12. l) Fine-grained or liquid nutrients, mineral salts and / or vitamins in the type and amount according to the needs of the application
13. m) salt for the production of fiber materials for silages
14. n) 1 to 20% by weight of acids and / or salts with preservative action
15. o) fertilizers in terms of proportion and type according to the needs of the application
16. p) Clay minerals and clay minerals in proportions dependent on the use case.

For further processing, the moist and bonded fibrous materials discharged from the flat-matrix pellet press are expediently processed by storage and / or drying and / or loosening comminution to give a fibrous material having a cotton-like structure. In this case, for the loosening comminution of the bonded pulp to a pulp with cotton-like structure after predrying to moisture contents of w ≤50% mechanical vortex mixers, disc mills, pin mills, impact mills, impact mills or beater mills with one or two rotors can be used. The drying and loosening of the pulp can be done simultaneously z. B. be performed with dryers that are equipped with mechanical loosening devices.

The material thus produced can be dried with less energy consumption, since the initial moisture content is lower than with the use of refiners. The pulp can then be pressed, in particular into pellets, strands, plates or the like. The product thus produced can then be used in many ways, depending on the composition. Applications are e.g. Materials and materials, building materials, reinforcements or fillers, cardboard, pore formers or fuels.

Depending on the application, pellet presses with smooth or profiled (grooved) surfaces of the pug mill rolls and / or dies can be used.

• Feinheit und Länge der Fasern sind variabel einstellbar
• die Intensität der Verdichtung des inneren Porenvolumens
• stärkere oder verminderte Hygroskopizität (Wasseraufnahmevermögen) der Faserstoffe
• Resistenz der Faserstoffe gegen Abbau durch Mikroorganismen
• Adhäsionseigenschaften der Faseroberflächen gegenüber Leimen oder anderen Bindestoffen können nach Bedarf eingestellt werden
• Besonders gute Kompressionseigenschaften der Faserstoffe z. B bei der Pressverdichtung zu Werkstoffen (geringer Widerstand der Fasern bei der Pressverdichtung und keine Rückexpansion nach der Pressverdichtung)
• Hohe Stabilität von Mischungen (keine Entmischung z. B. bei Faserstoffen, die als Futterstoffe verwendet werden). Feste Einbindung von z. B. Vitaminen, Mineralien, Schroten, Mehlen, Salzen in die Fasern
• Beschleunigung des Silierprozesses (Zerfaserung der Lignozellulosen bei Zugabe von Salz und evtl. anderen Hilfsstoffen)
• Deutliche Verbesserung der Trocknungseigenschaften gegenüber Spänen.

With the method according to the invention, the following properties can be achieved or set:

• The fineness and length of the fibers are variably adjustable
• the intensity of the compression of the inner pore volume
• greater or lesser hygroscopicity (water absorption capacity) of the fibers
• Resistance of the fibers to degradation by microorganisms
• Adhesion properties of the fiber surfaces to glues or other binders can be adjusted as needed
• Particularly good compression properties of the fibers z. B in the press compaction to materials (low resistance of the fibers in the compression of the press and no re-expansion after the compression of the press)
• High stability of mixtures (no segregation eg with fibrous materials, which are used as lining materials). Fixed integration of z. As vitamins, minerals, shot, flours, salts in the fibers
• Acceleration of the ensiling process (defibration of the lignocelluloses with the addition of salt and possibly other excipients)
• Significant improvement of the drying properties compared to chips.

Fig. 1

eine Prinzipdarstellung der erfindungsgemäß verwendeten Pelletpresse; und

Fig. 2

eine Draufsicht in Richtung des Zylinderachse der Kollerrolle der Pelletpresse der Fig. 1.

The invention will be explained below with reference to the accompanying drawings, for example. Show it:

Fig. 1

a schematic diagram of the pellet press used in the invention; and

Fig. 2

a plan view in the direction of the cylinder axis of the muller roller of the pellet press the Fig. 1 ,

In Fig. 1 the principle of a pellet press is shown in which rolling on a flat die 1 2 rolling rollers 2, which are acted upon in the direction of arrow 3 with a compressive force. The muller rolls 2 are thereby unrolled by the rotation of the king shaft 9 in the direction of arrow 4 on the die 1. The Good 7 is abandoned in the direction of the arrows 6, pressed by drilling the die 1, exits at the bottom of the same and is cut by a cutter 5. In contrast to the normal operation of a pellet press, part of the material at 8 can also emerge via an edge guard over the edge of the die 1.

In Fig. 2 the holes 10 of the die 1 are shown, through which the material 7 is pressed. The squeezing seam 12 designates the point at which the squeegee roller 2 touches the die 1 or comes closest to it. The material deviates here in the direction of the arrows 11 from the pressure seam 12 to the outside, as far as it is not pressed through the holes 10, which causes the intense shear stress of the material.

example 1

Production of the feed for the digestion process by mixing 60 wt .-% wood chips from spruce with a saturation water content of w = 58% and 40 wt .-% lignite with a grain size of 0 - 20 mm and a saturation water content of w = 54%. Further moistening of the mixture of raw materials during mixing in the Eirich mixer with water until the state of the mixed material, which has a very wet surface, of w = 62%. Digestion of the mix with a flat die pelleting press using a flat die with 4 mm round holes and a thickness of 20 mm is fitted. The circular holes in the die have an equidistant spacing of 4 mm from each other. The hole channel has a cylinder length of 5 mm in the upper part. Thereafter, the channel expands to a diameter of 6 mm. The round holes are not milled on top. The pressure in the hydraulic system is up to 200 bar. The pulping process in the flat die pelleting press produces a pulp which, as a bonded mass without pellet formation, is discharged through the holes in the flat die. The pulping material is pre-dried to water-content of about w≈45 to 50% until it is moist to the surface, and then dispersed by means of a hammering mill with a 4 mm conidurbite sieve to form a loose pulp having a cotton-like structure. After the residual drying of the pulp to a water content of w = 10%, a fine pulp is available whose fibers consist of an irreversible composite of wood and lignite. The new wood / carbon fibers are characterized by very good compression and binding properties as well as high resistance to microorganisms and macroorganisms. The fibers are hydrophobic in contrast to pure wood fibers. The wood / carbon fiber floats at least 4 months on the water, in contrast to Refinerfaserstoff. The processing into fiber materials produces solid and water-resistant end products.

Example 2

Mixing of 75 wt .-% wood chips with chip lengths of 5 to 20 mm and with a saturation water content of w = 54% and 25 wt .-% cement (dry) after its moistening to mortar with a Eirichmischer with simultaneous feeding from water to the setting of the surface moist state of the mix of w = 61%. Digestion of the mix with a flat pellet pellet press under the conditions given in Example 1. 7 days storage of damp pulp for setting the cement in the fibers. Loosening of the bonded pulp with a Schlagnasen mill with 4 mm conidur discharge screen and residual drying of the pulp to w = 20% for the production of glue-bonded fiber materials.

Example 3

Mixing of 70 wt .-% wood chips with a saturation water content of w = 57% and 30 wt .-% shredded and moistened rape straw with a saturation water content of w = 68%. The rapeseed straw is itself a lignocellulose, but it also acts as a fiber improver. Digestion of the mix with a flat pellet pellet press under the conditions given in Example 1. Loosening of the slightly bonded pulp with a mechanical vortex mixer. From the wet pulp with the addition of only 4 wt .-% urea-formaldehyde glue after wet hot pressing process with mold temperatures of 180 to 200 ° C particularly solid materials, because the pulp has achieved a high self-binding capacity by the modifying effect of rapeseed straw.

Example 4

Chopped maize plants in mixed maturity with a water content of w = 59% and a small proportion of rock salt (dry) in dissolved form are mixed. At the same time, the surface moisture is due to the addition of water Condition of the mixed material set at w = 68%. The digestion with the flat-matrix pellet press, which is equipped with a die with 15 mm round holes, produces a fibrous material that ensilages more quickly throughout and has a higher digestive value due to the intensive digestion of the coarse maize stalks.

Example 5

98% by weight woodchips having a water content of w = 45% and 2% by weight slaked lime (dry), which is previously dissolved in water and dispersed, are mixed. Additional moistening sets the surface wet condition of w = 61%. The extinguishing calcium solution strengthens the digestion of the wood into a pulp by its alkaline action. In addition, the Ca ions react during digestion with wood constituents. By digesting the lime-containing woodchips with the flat-matrix pellet press, which is covered with a die with 6 mm round holes, a pulp is produced which dries quickly. The drying time is reduced by 40% compared to wood chips with similar chip length. The pulp is also characterized by very good pelleting properties and the pellets produced from it burn particularly low emissions, because the pellets have a higher fire resistance and the slaked lime is effective as an additive.

Example 6

40 wt .-% chopped wheat straw with a water content of w = 18% and 60 wt .-% of the sugar beet geköpfte beet leaves with a water content of w = 76% mixed. Due to the digestion of the mixed material with the flat-matrix pellet press under the process conditions named in Example 1, a surface-moist, defibrated pulping material is formed under the sustained stress of the rolling element. The mushy mass, which arises from the beet leaves, penetrates the straw fibers and is absorbed by these completely without secretion of liquid. The result is a straw / beet leaf pulp that dries quickly and without the formation of water content margins and has good pelleting properties. The pellets are a high quality and storable feed.

Claims (12)

1. Method for the disintegration of lignocellulosic materials to fibers, wherein the lignocellulosic materials in admixture with fiber improvers are subjected in a surface moist state, in which the water content is approximately 5-15% higher than the saturation water contet, in a flat die pellet press to an adjustable rolling pressure by pan grinder rollers (2), whereby - augmented by the moisture in the interior of the pores in the fiber material - the fiber improvers penetrate into the interior of the fiber material and react there, wherein the disintegrated and enhanced material (7) is then subsequently forced through the drilled holes (10) in the flat die (1), so that the fiber improvers endow the fibers with improved properties for use as engineering, insulating, reinforcing or filler materials through physical and/or chemical reactions and also through partial filling of internal pore volumes.
2. Method according to Claim 1, characterized by disintegration of the surface moist material through a rolling pressure stress which is specifically adjustable in respect of intensity and duration.
3. Method according to Claim 1 or 2, characterized in that the pan grinder rollers (2) and/or the die (1) of the flat die press are subjected to adjustable spring force.
4. Method according to Claim 1 or 2, characterized in that the pan grinder rollers (2) and/or the die (1) of the flat die press are subjected to adjustable hydraulic pressure.
5. Method according to any one of Claims 1 to 4, characterized by pre-comminution of the selected recent and/or fossil lignocelluloses to a particle size of ≤ 200 mm and preferably ≤ 50 mm and also, if necessary, moistening of the raw materials sufficient to achieve the saturation water content specific to the particular raw material.
6. Method according to any one of Claims 1 to 5, characterized in that it utilizes a pellet press having pan grinder rollers (2) which are driven.
7. Method according to any one of Claims 1 to 6, characterized in that the disintegrated material discharges from the flat die pellet press not just through holes in the die (1) but additionally via an edge weir.
8. Method according to any one of Claims 1 to 7, characterized in that it utilizes one or more fiber improvers selected from the following group:

   a. 5% to 60% by weight of lignite having deposit dependent saturation water contents of 50 to 60%

   b. 10% to 40% by weight of cement (dry) after moistening to form mortar

   c. 1% to 40% by weight of slaked lime (dry) after moistening to form mortar

   d. 5% to 40% by weight of gypsum (dry) after moistening to form mortar

   e. 5% to 50% by weight of power station filter ashes (dry) after wet disintegration grinding to form a mortar mass

   f. 5% to 60% by weight of lean quark or quark rich enhancement products

   g. 5% to 25% by weight of protein rich extraction grains from oilseeds (dry) after wet disintegration grinding to form a finely disperse mass and/or through cooking of the pasty mass

   h. 3% to 15% by weight of starch or starch rich raw materials (dry) after disintegration into pasty glues or after thin cooking

   i. 1% to 15% by weight of sugar or sugar rich raw materials after dissolution

   j. 1% to 15% by weight of natural or synthetic glues

   k. 0.5% to 10% by weight of paraffins and/or asphalts, pitches, waxes, resins after liquefaction thereof

   l. finely granular or liquid nutrient materials, mineral salts and/or vitamins of the type and amount required in the use scenario

   m. salt for producing fibers for silages

   n. 1% to 20% by weight of acids and/or salts having a preservative action

   o. fertilizers of the type and proportion needed by the field of use

   p. clay and loam minerals in the proportions depending on the use scenario.
9. Method according to any one of Claims 1 to 8, characterized by aftertreatment of the moist and interadhered fiber discharged from the flat die pellet press through storage and/or drying and/or loosening comminution.
10. Method according to Claim 9, characterized in that the loosening comminution of the interadhered fiber to form a fiber having a waddinglike texture after a pre-drying to moisture contents of w ≤ 50% utilizes mechanical vortex mixers, disk mills, pin mills, bladed disk mills, impact plate mills or beater mills having one or two rotors.
11. Method according to Claim 9 or 10, characterized in that the drying and loosening of the fiber are carried out simultaneously with, for example, dryers equipped with mechanical loosening devices.
12. Method according to any one of Claims 9 to 11, in that the fiber is pressed, particularly into pellets, strands, plaques or the like.

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