WO2018137794A1

WO2018137794A1 - Extraction method for handling a lignin-containing mixture in a centrifuge

Info

Publication number: WO2018137794A1
Application number: PCT/EP2017/071191
Authority: WO
Inventors: Ernst Schaltegger; Nikolaus Foidl
Original assignee: Ferrum Ag
Priority date: 2017-01-27
Filing date: 2017-08-23
Publication date: 2018-08-02
Also published as: WO2018137792A3; WO2018137792A2; WO2018137793A1; WO2018137795A1

Abstract

The invention relates to an extraction method for performing in a centrifuge arrangement, comprising a centrifuge (Z, Z1, Z2) having a centrifuge drum (2) which is arranged such that it can rotate about a drum axis (T) and which extends with a drum casing (21) along the drum axis (T) from an inlet opening (22) to an outlet opening (23), wherein, on an inner peripheral surface (24) of the drum casing (21), a drum screen (3) is provided in which an ejection element (4) having a conveying device (41) with a conveyor opening (42) is arranged, wherein, in the operating state, the centrifuge drum (2) is supplied with a mixture (G) via the inlet opening (22), and the centrifuge drum (2) is rotated about the drum axis (T) in such a way that the mixture (G) under a drum pressure (P) generated by the rotation is deposited on an inner side of the drum screen (3), and the mixture (G) is a lignin-containing mixture (G), which is heated to a starting temperature of 100-400 degrees Celsius, and, by means of the conveying device (41), in an extraction step (ES, ES1, ES2), an extraction fluid (E) in the form of hot water is supplied into the centrifuge drum (2) at an extraction pressure of 1-150 bar and an extraction temperature of 100-400°C and applied via the conveyor opening (42) from the conveying device (41) into the centrifuge drum (2) to the mixture (G) deposited on the inner side of the drum screen (3) in such a way that lignin and hemicellulose are extracted from the mixture (G) by means of the extraction fluid (E).

Description

Extraction method for treating a lignin-containing mixture in a centrifuge

The invention relates to an extraction method for treating a

Mixture according to the preamble of independent claim 1, as well as a centrifuge assembly according to the preamble of independent claim 11. For dehumidifying damp substances or moist substance mixtures centrifuges in various embodiments are widely used and are used in a variety of fields. So come

For example, for dehumidifying high purity pharmaceutical products discontinuous centrifuges, such as peeler centrifuges, preferably used, while especially when continuously large amounts of a solid-liquid mixture to be separated, continuously operating pusher centrifuges are advantageously used. Depending on the requirements, one-stage or multistage pusher centrifuges, as well as so-called double-skid centrifuges, are used, as well as so-called double-skid centrifuges

Auger centrifuges and a number of other concepts have long been well known to those skilled in the art. Depending on the design, the centrifuges can be aligned vertically or horizontally with respect to the gravitational field of the earth and can be very specific depending on the application.

In the various types of pusher centrifuges, a solid-liquid mixture, a suspension or a wet salt or salt mixture is passed through an inlet pipe via a mixture distributor of a rapidly rotating drum, which is preferably configured as a filter, supplied, so that due to the centrifugal forces acting, the liquid phase is eliminated through the filter, while inside the drum wall under the action of the very strong centrifugal field, which is generated by the rapid rotation of the drum, a solid cake is deposited.

Here, in the case of pusher centrifuges in the rotating drum arranged a substantially disc-shaped, synchronous co-rotating pusher, with depending on the number of screening stages either the pusher bottom or a screening stage in the axial direction in the drum oscillates with a certain amplitude, so that a part of the dehumidified Solid cake is pushed out at one end of the drum. In the opposite movement of the moving floor, a, adjacent to the sliding floor area of the drum is released, which can then be fed through the inlet pipe and the mixture manifold again with a new mixture. Depending on the type used, modern high-performance

Pusher centrifuges easily be achieved throughputs in the order of 100 tons per hour, with drum diameter up to 1000 mm and more are quite common and typical rotational frequencies of the drum, depending on the drum diameter of up to 2000

Revolutions per minute and more can be achieved. In this case usually requires a larger drum diameter because of the strong centrifugal forces occurring a smaller maximum rotational frequency of the drum. Of course, the operating parameters, e.g. the

Rotational frequency of the drum, the amount of mixture supplied per unit time or the drum diameter or the type of pusher centrifuge used also depend on the material to be dehumidified itself, the content of liquid and so on. The known from the prior art pusher centrifuges are usually continuous filter centrifuges. One-stage and multi-stage pusher centrifuges are known, the multi-stage pusher centrifuge from an outer Screening drum and at least one in the outer screening drum

arranged screening stage, which is also designed as a screen drum consists. Several screening stages can be concentric

be arranged so that two, three and multi-stage pusher centrifuges are feasible, all screening stages are driven very quickly synchronously about a common axis of rotation. A solid-liquid mixture to be separated passes in the operating state continuously through a fixed inlet pipe in a arranged in the innermost screening stage, also synchronously co-rotating, mixture distributor and is evenly distributed on the innermost screening stage over the entire screen circumference. Most of the liquid is already centrifuged off here and a solid cake is formed. In contrast, a single-stage pusher centrifuge does not include any further screening stages except the outer screening drum. Here, in order to convey the solids cake in the sieve drum, the moving soil oscillates, which simultaneously co-rotates synchronously with the outer sieve drum. In a two-stage pusher centrifuge performs the innermost stage, which is also referred to as the first stage, in addition to the rotational movement about the axis of rotation of an oscillatory movement in the direction of the axis of rotation. This oscillatory movement is hydraulically via a thrust piston

Reversing mechanism generated. As a result, the solid cake is in

Ring sections, according to the stroke length of the oscillation, pushed from the first to the second stage and finally leaves the pusher centrifuge via an outlet opening. In practice, while the solid cake in the sieve drum continuously with the addition of washing liquid on the

Washed solid cake. For special applications are

Special versions, in particular of two- and multi-stage

Pusher centrifuges, in particular for highly abrasive products, such as e.g. Charcoal and rock phosphate known to be special

Wear protection measures, such as wear-resistant sieves, require. Also special versions for intensive washing processes and to carry out special washing processes, such as countercurrent washing at Nitrocellulose are known in the art. Gas-tight versions of single-stage and multi-stage pusher centrifuges for operation under a protective gas atmosphere are also used.

The functioning of peeler centrifuges is described here using the example of horizontal peeler centrifuges. The solid-liquid separation in horizontal peeler centrifuges is discontinuous in a sequence of specific process steps. According to the product characteristics, the individual process steps take a few minutes to several hours. At the

Filling the suspension is applied via a Füllschwert evenly on the centrifuge drum. The horizontal peeler centrifuge

accelerated to spin off the liquid over the product cake. The washing liquid is uniformly over the wash tube on the

Product cake abandoned. After washing, the spinning takes place until the desired residual moisture of the filter cake is reached. At reduced speed, the paring knife pivots into the product cake and peels the product vertically downwards via the discharge chute. Depending on the product characteristics and drum width, a discharge screw is installed instead of the chute. To protect the filter cloth clamped in the drum, a product residue remains on the filter cloth during peeling. This layer may optionally in the following batches the

Prevent penetration of fines into the filtrate. The residual layer in the horizontal peeler centrifuge is removed application-specifically after each batch or periodically. With gas pressure surges via nozzles outside the drum, the layer can be blown off via the discharge chute. If the process space is rendered inert, the nitrogen is blown off. In other, preferably smaller centrifuges, the solid can also be removed manually after stopping the centrifuge.

Centrifuges are particularly suitable for the washing of substances because they have a lower throughput rate as the pusher centrifuges. A Centrifugal screw basically consists of a rotor of one

Full-barrel drum and a screw body mounted therein has. Both are running at a high speed, the worm a

Differential speed to the surrounding drum has. The mixture to be separated is supplied centrally via an inlet pipe and passes through holes in the screw body in the actual separation space. Due to the centrifugal field, a circular-cylindrical liquid space is formed in the separation space. Due to the density difference between the denser material and the less dense liquid, the solid deposits in the form of a solid cake on the inner wall of the drum. About the solid, the clarifying liquid flows into the channels formed by the screw blades and decanted into the liquid housing.

The process of washing with the different types of centrifuges does not necessarily have to be done with liquids only. When washing with steam, the resulting condensate assumes the function of the washing medium. In addition to reducing the balance lead

Displacement effects for a purification of the solids cake. The

Steam washing is usually completed with breakthrough of the condensation front through the solid cake. It is already known in the prior art that centrifuges are not only suitable for washing but also for extracting substances from mixtures. Extraction of substances such as active ingredients, flavors, vitamins, etc. from a mixture into a liquid phase by means of centrifugal force. In liquid-liquid extraction with decanter centrifuges, two liquids which are insoluble in one another are mixed with the aim of transferring a solute from the starting liquid into the extraction liquid. In the solid-liquid, the liquid is applied to the solid cake and the centrifugal force is carried out an optimal mass transfer from the carrier phase into the solvent phase. The steam extraction works in the Principle like you steam washing only the valuable component is not the solid cake but the condensate. The procedure is only at

Inverted filter centrifuges applied. Here, the centrifuge with a

Solid suspension filled and the mother liquor thrown off. Then the steam extraction is carried out by applying hot steam to the drum, which flows through the solids cake from the inside to the outside. The condensate containing the substrate after flowing through the solids cake is collected in the filtrate. Such processes find e.g. Use in the extraction of active ingredients from herbs. DE 3631470 C1 describes a process for the recovery of beer from the fermentation cellar or storage cellar yeast of breweries. The extraction liquid is circulated via the centrifuge and then the yeast is added to the extraction liquid. In the

Centrifuge, extraction liquid and yeast are immediately separated again. In addition, extraction methods are known, for example the

High pressure extraction with supercritical gases. Gases assume a state at high pressures and temperatures that does not correspond to either a gas or a liquid, this region being called supercritical or supercritical. For example, with supercritical CO2

Extractants derived from food or unwanted

Extracting Extractants: Caffeine from coffee beans, hop resins from hops, nicotine from tobacco, flavors and dyes and ingredients from a wide variety of spices, aromatic plants and natural products. With supercritical CO2 but also the reverse process, the

Impregnate done. For this purpose, a solid starting material is contacted with the impregnating agent dissolved in the supercritical CO2, whereby the

Impregnating penetrates into all pores of the starting material. By slowly relaxing, the supercritical CO2 loses the ability to dissolve and the impregnating substance remains evenly distributed in the starting material. WO 96/33861 A1 describes a continuous extraction process and a corresponding extraction apparatus. For extracting oils by compressing and extracting an oily raw material in

In the presence of a liquid and / or supercritical extraction fluid, a substantially cylindrical reactor provided with inlets and outlets is provided for this purpose. In the reactor, a screw press is provided, which conveys the raw material from the inlet under compression to the outlet of the reactor, wherein at the same time the extra ktionsfluid is introduced under pressure into the reactor. In this case, an oil or an extracted substance is obtained, from which subsequently the extraction fluid can be removed.

A major disadvantage of the known devices for extraction and extraction processes is their constructive and procedurally very complicated structure and the complex implementation of the method, since often several reactors with complex pressure generators are necessary.

For example, the devices for extraction and the need

Extraction method pressure-tight supply device to a reactor and pressure-tight reactors. Considering the high pressures required, there are considerable high costs for the wall thicknesses of the reactors, as well as the need to move batchwise or batchwise. Likewise, due to the reactors long extraction times of sometimes up to well over ten minutes are necessary. Also, a complex supply and removal of the mixture and the transport within the reactors with high-pressure-tight, rotating screws and feedthroughs of

Disadvantage necessary. In addition, the extraction or throughput times are high and the processes are often not so continuous to operate. Not to be underestimated and another major drawback, due to the complexity, are the high susceptibility to failure and the high maintenance intensity of the extraction devices and the extraction methods.

Likewise, centrifuges are known in which, for example by means of a supply line and a nozzle, a solvent on the in a in the Centrifuge drum arranged sieve sedimented mixture is sprayed. However, these centrifuges have the disadvantage that in addition to the limited volume in the centrifuge drum lines and nozzles are still to order, so that the known centrifuges are structurally complicated and expensive to manufacture in terms of manufacturing.

All of these types of centrifuge have long been well known to those skilled in the art and are e.g. in the standard work "industrial centrifuges", by Prof. W. Stahl, DRM PRESS, described in detail.

The main components of any wood or biomass-based fiber used, for example, in the paper industry consist of

Hemicellulose, cellulose and lignin. Lignins are polymeric phenylpropanes whose incorporation into the cell wall leads to woodiness of the plant. Thus, the hardness of wood depends on the degree of lignification (= woodiness). Depending on the type of wood, there is a different degree of lignification. The harder the wood, the higher the lignin content. The lignin extraction is not only of interest to the paper industry. In the near future, the extraction of lignin via various lignin digestion processes will be an integral part of industrial raw material extraction. The biomass is not only suitable as an energy source, but also provides a source of various polymers that can be used as adhesives or binders.

Originally, low-chemical or chemical-free processes were planned to dissolve the hemicellulose and cellulose from the dressing and to render the cellulose pure for alcohol production (fermentation). However, the cellulose, hemicellulose and lignin are closely related. The partially crystalline structure of cellulose and the covalent bonds of lignin to carbohydrates complicate the

Separation of components. Therefore, a variety of lignin solution processes have been developed in recent years, including the Organosolve method

Aquasolve method and the Liquid Hot Water (LHW) method.

However, the most widely used lignin extraction process is the sulfate process (Kraft digestion). In the sulfate process wood chips or crushed plant parts are boiled for several hours at elevated pressure (7- 10bar) in sodium hydroxide solution with sodium sulfide and sodium sulfate. This results in a cleavage of the lignin in the so-called black liquor (soluble alkali lignin). The black liquor can be separated by filtration from the pulp.

In the Organosolv process, water and organic solvents (alcohols), preferably ethanol and ethylene glycol, are added as a mixture

Temperatures between 120 to 180 degrees Celsius used. The biomass is crushed and then, after prehydrolysis with a Brønsted acid, treated with the solvent. By using catalysts, such as redox catalysts, in the solution process, better results are achieved. By a multi-stage countercurrent extraction with alcohol-water mixtures a solution can be obtained, which contains lignin and carbohydrates. The alcohol is distilled off, whereupon the lignin precipitates. In the Aquasolv method, the wood or biomass is soaked in superheated water and thereby by the softening effect of

Water plasticizes the lignin. A small part of the lignin goes into solution. By abrupt relaxation one reaches a resolution up to the fiber. The Liquid Hot Water (LHW) process uses deionized water under pressure at temperatures up to 260 degrees Celsius. Here, hemicellulose and lignin are dissolved out of the cellulose dressing, which then passes through Concentration and cooling are precipitated in different stages. The cellulose can then be further processed in fermentation processes.

Subsequent to one of the above-described method can with a catalyst, preferably a Brønsted acid catalyst such

Sulfuric acid, be hydrolyzed. This results in a hydrolysis of the cellulose to glucose, which is then reacted via fermentation with enzymes to other products, preferably ethanol. Lignin remains as an insoluble residue. A major disadvantage of the known sulfate process are the disturbing emissions and the resulting odor nuisance by ejecting thiols and hydrogen sulfide. It's a straight-forward, chemo-heavy one

Process which requires many components. In addition, the process yields a low yield of softwoods and intensive bleaching is required, as only low degrees of whiteness are achieved. Apart from that, complex equipment is involved in the process

alkali-resistant pressure reactors needed. The need for high pressures in the reactors requires a lot of energy.

A major disadvantage of the known Organosolv process is their procedurally demanding structure. The use of acid or bases in the prehydrolysis of the biomass requires reactors which are corrosion resistant. In addition, not only organic solvents are used in the process but also other reagents (redox catalysts or others), whereby recycling is required in order to minimize the environmental impact. These factors make the Organosolv process a relatively expensive process. Furthermore, the choice of reaction conditions for the Organosolv process is very high consuming, as selective chemicals are needed which are easy to separate so as not to affect the quality of the lignin.

A major disadvantage of the known Aquasolv process and the LHW process is the low lignin yield. For most hardwoods only up to 80% removal of lignin and softwoods up to 45-60% solubility and thus extraction of lignin is possible. Of

Further, in the previous LHW method, the use of

Pressure reactors disadvantageous because in the first 2-3 minutes of the hot water pressure treatment, the solubility and degradation of lignin about a factor of a hundred higher than the incipient re-condensation / precipitation of dissolved lignin and lignin derivatives back to the remaining

Cellulose fibers is. In stirred pressure vessels is so with increasing

Residence time to expect even with increasing precipitation. This not only clogs pipes and valves, it also drastically reduces the initial high resolution and separation of the lignin. Thus, the pressure reactors in the LHW process are not only expensive to maintain and purchase, but also do not allow efficient separation of the mixture. This disadvantage is also evident in all processes in stirred pressure vessels.

Based on this prior art, it is therefore an object of the present invention, a centrifuge for carrying out a

Extraction process to propose an extraction process for the treatment of a lignin-containing mixture, which largely avoids the disadvantages known from the prior art, in particular to propose a centrifuge for carrying out an extraction process and an extraction process for the treatment of a mixture, the constructive and

procedurally simple and / or low

Have throughput times for extraction and / or can be continuously controlled and controlled, so can be operated continuously. Apart from that, a process for the extraction of lignocellulose with high yield and high quality of lignin is proposed, which is an environmentally friendly and low-chemical variant.

If one were to apply the present invention to the sulphate process, the process would proceed as follows. A decanter would be charged with the fiber reaction mixture. In the centrifugal force field of the decanter, high pressures are achieved (20-100bar). The fiber reaction mixture migrates slowly through the decanter, the educt mixture (water, sodium hydroxide solution, sodium sulfide, sodium sulfate) being continuously sprayed onto the fiber mass located in the gravitational field, and this in the gravitational field

Separated by separated reaction mixture (black liquor) and under pressure from the decanter into a corresponding

Discharge tank is discharged. If several decanters are connected in series, the extracted fiber mixture can subsequently be washed with water to remove the rest of the black liquor and then optionally bleached in a following decanter. This process has the advantages, compared to the prior art, that no pressure reactors are required, which is a great deal

Energy saving supplies. Furthermore, due to the high pressures and the possible higher temperature in the gravitational field of the decanter

Reaction rate significantly increased, thereby saving time.

This object is achieved by a centrifuge assembly having the features of claim 11 and an extraction method for treating a

Ligninhaltigen mixture solved with the features of claim 1. The dependent claims relate to particularly advantageous

Embodiments of the invention.

According to the invention, it is proposed to treat a lignin-containing mixture in a centrifuge arrangement. This becomes a ligninhaltiges Introduced mixture through an inlet opening in the centrifuge drum and heated to a starting temperature of 100-400 degrees Celsius, preferably to a starting temperature of 100-350 degrees Celsius, and more preferably to a starting temperature of 120-280 degrees Celsius. By means of

Conveyor of the centrifuge is in an extraction step

Extraction fluid in the form of hot water at an extraction pressure of 1 to 200 bar, preferably from 1 to 150 bar, more preferably 1 to 100 bar and in particular from 10 to 100 bar, an extraction temperature of 100- 400 ° C, preferably at an extraction temperature of 100-350 degrees Celsius, and more preferably at an extraction temperature of 120-280 degrees Celsius, fed into the centrifuge drum and so on the

Delivery opening from the conveyor into the centrifuge drum is applied to the deposited on the inside of the drum screen mixture that lignin and hemicellulose are extracted from the mixture by means of the extraction fluid.

According to the invention, a centrifuge arrangement for carrying out a lignin extraction method is proposed. The centrifuge assembly includes a centrifuge with a rotatable about a drum axis

arranged centrifuge drum having an inlet opening and a

Includes outlet. The centrifuge drum can be supplied with a mixture via the inlet opening. On an inner peripheral surface of the drum shell, a drum screen is provided, in which a standing under the drum pressure generated by the rotation mixture is deductible. Inside the centrifuge drum is a conveyor with a

Feed opening. In the operating state by means of the conveyor a

Solvent be fed into the centrifuge drum such that from the deposited on the inside of the drum screen mixture, an extractant can be extracted.

It is essential for the invention that the mixture of the drum can be fed, wherein the mixture due to the rotation of the centrifuge, in particular the Drum, and in particular due to the high speed and the high centrifugal force acting on the inside of the drum can be brought quickly to the rotary pressure, so that the mixture, preferably a biomass, more preferably a vapor-saturated biomass, on the inner wall of the drum of a fast , high and efficient

Pressure increase is exposed, which heats the mixture further.

It is essential for the invention that the mixture is heated and acted upon with hot Extra ktionsfluid, in particular that the extract is rapidly separated by the rotation in the centrifuge from the mixture to prevent reconstitution of the lignin.

Essential for the invention is that the extraction fluid is water, as a lignin of particularly high quality is obtained.

In the following, a mixture is generally to be understood as meaning that the mixture consists of at least two substances, it being possible for the mixture to be a homogeneous or heterogeneous mixture, and for the substances to be solid, liquid or gaseous. The

Mixture, in particular the mixture which can be supplied via the inlet opening, can be a liquid phase and / or a solid phase, wherein the

In particular, a solid phase may also be a colloidal liquid, and / or comprise a gas phase. The settable mixture which is under rotary pressure may be the solid phase or colloidal

Be liquid, and is also called solid cake in particular. However, the settable mixture which is under the rotary pressure may also comprise portions of the gas phase, which are liquid due to the rotary pressure, or portions of the liquid phase. However, a substantial proportion of the liquid phase may be separable from the settable mixture due to the rotational pressure. In the following, a lignin-containing mixture is generally understood to mean a mixture that contains a biomass, in particular a Biomass mixture of different origin and composition. In this case, the lignin-containing mixture comprises lignocelluloses, ie in particular lignin and its derivatives, hemicellulose and cellulose. For example, a lignin-containing mixture may be understood to be woody or agricultural waste or raw material from livestock and agriculture. The lignin-containing mixture may be mixed with a liquid and / or a solution. In the following, an extractant is generally understood to mean lignin and its derivatives and hemicellulose which has been extracted from the mixture by the extraction methods described. In the following, an extract is generally to be understood as meaning, in general, the liquid extract from the lignin-containing mixture, which is obtained after centrifuging and contains lignin and other extractants. In the following, an extra ktionsfluid is generally understood to mean water, which is in particular in gaseous and / or liquid and / or supercritical and / or vaporous state. In the following, a residual lignin is generally to be understood as meaning the remainder of lignin, which is not in a preceding one

Has solved extraction step. In the following, a digestion is generally understood to mean a physical and / or chemical and / or biological digestion. A digestion is a process in which sparingly soluble substances, with the aid of physical, chemical or biological decomposition agents, are converted into soluble compounds and / or states and / or a process for opening cells.

In particular, this means a digestion of lignocellulosic biomass, ie, for example, the mechanical and chemical-technical pulping of wood. A partial digestion is a process in which plant material is not defibrillated by chemical treatment alone, but the half-pulp thus obtained is further defibrated by physical methods. In particular, this means a partial digestion of lignocellulosic biomass. Under an enzymatic treatment is in the following generally a biochemical and / or biotechnological and / or to understand microbiological treatment with an enzyme complex. In the following, a solvent is generally understood to mean a substance which, in particular, is in gaseous and / or liquid and / or supercritical and / or vaporous state and dissolves out a constituent of a mixture. In particular, a solvent may be an aqueous solvent and / or an organic solvent,

in particular an alcohol and / or an acid and / or a ketone such as e.g. Methanol, ethanol, ethylene glycol, acetone, formic acid and acetic acid. In particular, a solvent may also be an extra ktionsfluid. The rotational pressure is caused by the rotation of the centrifuge, in particular the drum, the centrifugal force acting on the inside of the drum. Under the rotary pressure, especially a high

Rotational pressure, hereinafter a rotary pressure with a with a rotary pressure range of 1 to 200 bar, preferably 1 to 100 bar, particularly preferably 10 to 100 to understand bar.

The centrifuge may be a vertically or horizontally mounted centrifuge, a continuous or discontinuous centrifuge, in particular a peeler centrifuge, sliding centrifuge, single or multi-stage pusher centrifuge, double pusher centrifuge or vibrating centrifuge or a

Be slug centrifuge. The drum can be rotatable in a first direction of rotation. The drum can be rotatable at a drum speed of 1 to 10,000 revolutions per minute, preferably at 500 to 10 000 revolutions per minute, more preferably at 1000 to 4000

Revolutions per minute, in particular be rotatable at 1500 to 3000 revolutions per minute. The drum may be hollow cylindrical, preferably formed as a first hollow cylinder. However, the drum can also have a round and / or circular and / or elliptical cross section in a radial direction, that is to say orthogonal to the drum axis. In principle, the drum may also have a prism-like shape and / or be formed as a prism and in the radial direction a triangular and / or have rectangular and / or polygonal cross-section. The tunnel may be drivable with a first motor, in particular a frequency-controlled first motor, in order to be able to use the drum to control the throughput quantity and the throughput time of the mixture. The drum can outside, so for example on an outside of the drum against

Heat losses to be thermally insulated.

The extraction process for treating a lignin-containing mixture can be carried out in various ways. The lignin-containing mixture may be heated to the starting temperature prior to introduction into the centrifuge, the mixture may also be heated upon delivery or a centrifuge may have a heater which brings the mixture to the desired starting temperature. When applied to the mixture, the extraction fluid and / or the solvent may be gaseous and / or liquid and / or supercritical and / or vaporous. The advantages of the centrifuge arrangement according to the invention and the lignin extraction method mentioned later are:

- low throughput times and / or short residence times of the

Mixture in the centrifuge assembly, in particular in the

Centrifuge, and / or

a high throughput and high processing capacity of the mixture compared to known devices and

Pressure reactors and / or

- Constructively simple designed centrifuge assembly and / or procedurally simple designed and / or low Herstell cost associated lignin extraction method, in particular continuous lignin extraction method with various types of biomass, and / or

- High energy efficiency due to the recirculation of the fluids and the avoidance of pressure reactors - The centrifuge assembly has a much smaller

Device geometry with a high energy efficiency with low residence times compared to the known devices for lignin extraction, in particular with respect to the reactors.

The lignin extraction process provides lignin and hemicellulose of high quality, which is not affected by the process

- The lignin extraction method yields high yields, as a

Recondensation is avoided by the rapid removal of the extract

- The lignin extraction method provides a chemistry-free variant

Comparison to other industrial processes

In an embodiment of the invention, the ejection element in the form of a helical coil is formed with an ejection surface, preferably the ejection element is an ejection screw, and the ejection element is rotatable in the operating state to an ejection axis such that the mixture with the ejection surface along the ejection axis is movable, or Ejection element is a push floor device and the

Push floor device is in the operating state so along the

Ausausossachse arranged to move back and forth, that the mixture with the push floor device, preferably with a thrust surface of the

Moving floor device, along the ejection axis is movable. The ejection element may preferably be arranged at a small distance from the inside of the drum in the drum. The ejection element can be arranged at least partially at the outlet opening of the drum. The ejection axis may preferably coincide with the drum axis, wherein the ejection axis can also assume a different position from the drum axis. The ejection element can, in particular the

Ejection screw, be rotatable in the first direction of rotation like the drum and with an output speed of 0 to 300 revolutions per minute Turning differential rotation to the drum speed, preferably 0 to 150 revolutions per minute, more preferably 0 to 50 revolutions per minute, in particular 5 to 15 or 0 to 20 revolutions per minute

Differential rotation to the drum speed to be rotatable or rotatable. The ejection element may be drivable with a second motor, in particular a frequency-controlled second motor, in order to operate with the

Output element to control the flow rate and the throughput time of the mixture. The ejection element can, in particular when it is designed as a sliding floor device, in the operating state either an oscillatory relative movement between the moving floor device and the immovable in the axial direction of the drum and / or between one or more possibly existing drums perform, so back and forth to be movable. The rotation and / or the oscillatory movement of the ejection element can preferably via a push rod or a

Conveyor shaft done. Advantageously, the mixture is feasible in a structurally simple manner in the drum and out of the drum executable.

In an embodiment of the invention, the ejection element comprises a hollow shaft, wherein the hollow shaft preferably has an inlet opening and / or a

Outlet opening, particularly preferably the hollow shaft circumferentially one or more inlet openings and / or one or more

Has outlet openings. By means of the inlet openings in the hollow shaft, the extraction fluid is traceable into the hollow shaft, and / or by means of

Outlet openings from the hollow shaft in the drum traceable. The

Push rod or a conveyor shaft may preferably be designed as a hollow shaft. The hollow shaft may have a hollow cylindrical shape, and preferably also be designed as a second hollow cylinder. However, the hollow shaft can also have a round and / or circular and / or elliptical cross section in a radial direction, that is to say orthogonal to the ejection axis. In principle, the hollow shaft and a prism-like shape and / or be formed as a prism and in the radial direction have a triangular and / or rectangular and / or polygonal cross-section. Advantageously, the hollow shaft thus allows with the

Inlet opening and / or the outlet opening, that the extra ktionsfluid in the centrifuge, in particular in the drum, traceable, whereby the

Energy consumption by the return of the extraction fluid, in particular due to the large amounts of the extraction fluid, preferred

Water vapor, is substantially lower than in the known devices and methods. Furthermore, due to this measure, the

Extra ktionsfluid in the drum by means of the rotary pressure back into the

Be converted liquid phase and / or recondensed and / or reused.

In an embodiment of the invention, in the lignin extraction method in a centrifuge, a first pressure and / or a second pressure different from the first pressure and / or a first temperature and / or a second temperature different from the first temperature can be set. If a lower pressure and / or a lower temperature are then set in the centrifuge first and then a higher pressure and / or a higher temperature, several extraction substances can be successively dissolved out of the mixture in order to avoid subsequent separation of the individual extraction substances. In particular, only hemicellulose can be dissolved in a centrifuge under a pressure of 10-25 bar, in particular at 20 bar and at a temperature of 100 to 180 degrees Celsius, in particular at a temperature of 120 to 160 degrees Celsius. In an embodiment of the invention, a cavitation rotor is provided in the drum, the cavitation rotor preferably between the

Inlet opening of the drum and the ejection element is arranged, particularly preferably the Kavitationsrotor in the operating state by a

Rotor axis is rotatable. The cavitation rotor is rotatable in a second direction of rotation. The first direction of rotation and the second direction of rotation can match, wherein preferably the second direction of rotation is opposite to the first direction of rotation. The drum axis, ejection axis and

Rotor axis may coincide or take a different position in space. The cavitation rotor can

be hollow cylindrical, preferably be designed as a third hollow cylinder. However, the cavitation rotor can also have a round and / or circular and / or elliptical cross section in a radial direction, that is to say orthogonal to the rotor axis. In principle, the cavitation rotor may also have a prism-like shape and / or be formed as a prism and have a triangular and / or rectangular and / or polygonal cross-section in the radial direction. The cavitation rotor can be driven by a third motor, in particular a frequency-controlled third motor, in order to be able to use the cavitation rotor to control the throughput quantity and the throughput time of the mixture. The first engine and the second engine and the third engine may be the same engine or different engines. The drive device may for the first, second and / or third motor, a direct clutch and / or a

Be pulleys. Advantageously, the mixture with the

In addition, the mixture is additionally in a very short time, so in 1 to 10 seconds, preferably 3 to 8 seconds, mixed and cavitated, i. mechanical forces act on the mixture and thus ensure better mixing of the mixture. Likewise, the mixture due to the rotation of the

Cavitation rotor in the opposite direction additionally mechanically treated and / or better mixed. In an embodiment of the invention, an extract can be removed into a container in the extraction process. In the container can a

Extractant are partially precipitated. Dominates in the container a certain pressure and / or a certain temperature can

Hemicellulose and lignin are partially precipitated. In addition, hemicellulose and lignin can be partially precipitated by concentrating the extract in several steps and thus precipitating the less soluble substance first. In an embodiment of the invention, at least a first centrifuge and a second centrifuge can be arranged in series in the extraction process, so that the lignin-containing mixture is first subjected to a first extraction step in the first centrifuge, and then from the first centrifuge to perform a second extraction step of the second centrifuge is supplied. Here, the extraction step may be a digestion, a partial digestion or an enzymatic treatment. Through sequence of different process steps

(Extraction / digestion / enzymatic treatment) in series

switched centrifuges can be extracted from the mixture, the extractants not only sequentially, but the extraction time can be reduced. In addition, the yield of extractants will be increased. The various process steps can also be carried out in a centrifuge in successive steps. In particular, in a first centrifuge under a pressure of 10-25 bar, in particular at 20 bar and at a temperature of 100 to 180 degrees Celsius, in particular at a temperature of 120 to 160 degrees Celsius, only hemicellulose can be dissolved in a second centrifuge To dissolve lignin.

In an embodiment of the invention, in the extraction process after the extraction step with hot water, an organic solvent The mixture located on the inside of the drum screen are applied to remove the residual lignin.

In an embodiment of the invention, in the extraction process, in particular before the lignin extraction, a digestion and / or partial digestion of the lignin-containing mixture can be carried out. The lignin-containing biomass can be mechanically disrupted by the cells are digested with a mortar and / or ultrasound and / or cavitation and / or a press and / or shear forces and / or pressure relief.

In addition, the lignin-containing biomass can be non-mechanically digested by the cells are enzymatically digested and / or denatured and / or the membrane lipids are dissolved and / or by saponification of Membraniipide. The lignocellulosic biomass can

be disrupted by adding sparingly soluble components

Disintegrating agents are converted into soluble compounds. In particular, mechanical digestion methods, such as the grinding method and / or the refining method or the chemical-technical method, such as the sulphate method and / or the sulphite method and / or the soda method can be used for digestion.

In an embodiment of the invention may in the extraction process, the centrifuge assembly and / or one of the centrifuges a

Inertgasatmosphäre be generated. In an embodiment of the invention, the delivery opening of the extends

Feed along a discharge axis of the conveyor and are in particular formed as a nozzle and / or as a bore.

In an embodiment of the invention, the centrifuge assembly and / or a centrifuge of the assembly may include a heater to the mixture heat. The centrifuge assembly may also have a heater at the inlet port and / or in front of the inlet port to heat the mixture prior to introduction.

In an embodiment of the invention, the centrifuge assembly may consist of several series-connected centrifuges. Different temperatures and / or pressures can prevail in the different centrifuges, so that different components of the mixture, in particular lignin and

Partially dissolve hemicellulose. In addition, various process steps can be performed in the centrifuges of the centrifuge assembly. Thus, in a first centrifuge before and / or between the

Extraction steps take place a digestion and / or a partial digestion and / or an enzymatic treatment. In particular, before and / or after an extraction step with water and / or after a digestion and / or after a partial digestion and / or after an enzymatic treatment, an extraction step with an organic solvent, in particular ethanol and / or methanol and / or ethylene glycol can take place.

In an embodiment of the invention is at the outlet opening a

Relaxation tank provided. With the ejection element, the mixture which can be deposited on the inside of the drum under a high rotary pressure is simply conveyed via the outlet opening of the

Centrifuge drum into the expansion tank with the low

Tank pressure can be guided out of the drum. Because of the fast

Pressure change from the high rotary pressure in the centrifuge, in particular the drum, to the low tank pressure in the flash tank, the settleable mixture is explosively relaxed. In this case, the portion of the gas phase in the settable mixture which is under the rotary pressure, in particular the portions of the gas phase which are in the liquid or solid phase due to the rotary pressure, are due to the lower one

Tank pressure back into the gas phase, ie the settleable mixture relaxes in a very short time and is torn apart explosively. In particular, when the lignin-containing mixture is a biomass or a

Biomass mixture is, for example, lignocelluloses which are mixed with water or another solvent, are by the

Pressure change from the high rotary pressure to the low tank pressure, the fiber composite and the cell walls of the mixture torn up and torn apart.

In an embodiment of the invention, the relaxation tank is a

Discharge provided, so that the relaxed mixture with the discharge from the flash tank can be discharged. in the

Furthermore, the centrifuge arrangement may comprise a condenser, wherein the condenser is preferably arranged on the expansion tank, so that the expanded mixture, in particular the extraction fluid, by means of

Condensation is liquefiable. The centrifuge assembly may also comprise a further ejection screw, wherein the further ejection screw is preferably arranged on the expansion vessel, so that the relaxed mixture, in particular the relaxed solid cake, in or on or from the flash tank is feasible. The condenser advantageously makes it possible to liquefy the extraction fluid, in particular gases and vapors, as well as entrained substances by means of condensation and thus allows the extraction fluid to be fed to a further fractionation or recycling. The further ejection screw, which can also be an ejection element, can be arranged on the expansion vessel, preferably connected to the expansion vessel or also in this

be arranged. The further ejection screw makes it possible to lead the mixture away from the centrifuge arrangement, in particular further

Devices and / or methods, as described above, supply.

In an embodiment of the invention, the centrifuge assembly comprises a

Pump, preferably a high-pressure solids pump, wherein the pump

preferably at the inlet opening, particularly preferably outside the Drum is arranged, and / or the centrifuge assembly a

Steam generator includes, wherein the steam generator preferably at the

Inlet opening, particularly preferably outside the drum is arranged. The pump may be a frequency-controlled pump and / or be controllable by a transmission. The pump has the advantage that the mixture, before it can be supplied to the centrifuge, in particular the drum and / or the cavitation rotor via the inlet opening of the drum, can additionally be brought to a pump pressure. The steam generator has the advantage that the mixture, before it can be supplied to the centrifuge, in particular the drum and / or the cavitation rotor via the inlet opening of the drum, additionally a gas, preferably a water vapor, can be supplied.

In an embodiment of the invention in the extraction process the

Centrifugal arrangement according to one of claims 1 1 to 15 used according to the invention. Further advantageous measures and preferred process guides emerge from the dependent claims.

In the following, the invention is described both in apparatus and in

procedural terms explained with reference to embodiments with reference to the drawings.

The schematic drawings show:

Fig. 1 shows a first embodiment of the inventive

Centrifuge arrangement, and

Fig. 2 shows another embodiment of the inventive

Centrifuge arrangement, and Fig. 3 shows a first embodiment of the inventive

Extraction method, and

Fig. 4 shows a further embodiment of the inventive

Extraction method, and Fig. 5 shows a further embodiment of the inventive

extraction process

Figure 1 shows a schematic representation of a first

Embodiment of the inventive centrifuge assembly with a centrifuge 1 for performing an extraction method. The

Centrifuge assembly comprises a centrifuge 1 with a centrifuge drum 2, which comprises an inlet opening 22 and an outlet opening 23, and has a hollow cylindrical shape, preferably formed as a first hollow cylinder. Furthermore, the centrifuge Z, Z1, Z2 comprises a

Cavitation R which comprises an inner circumferential surface R2 and blind holes R1 and preferably between the inlet opening 22 of the

Centrifugal drum 2 and the ejection element 4 is arranged, particularly preferably the cavitation R in the operating state about a rotor axis which is equal to the drum axis T, is rotatable. Through the cavitation rotor, the mixture G can be supplied to the centrifuge drum 2 while being mixed and heated. In addition, the addition of the extraction fluid E can also take place via the cavitation rotor R. The centrifuge drum 2 is in the operating state about a drum axis T such in a first

Rotatable direction of rotation that on an inner peripheral surface of the

Drum sleeve 21 in particular an inner drum shell surface, a standing under a rotary pressure mixture is deductible. In the

Centrifuge drum 2 is arranged an ejection element 4, wherein the ejection element 4 is preferably at least partially disposed at the outlet opening 23. In addition, the centrifuge assembly comprises

Ejection element 4 with a conveyor 41st The conveyor 41 is formed as a centrifuge screw 41 1 and comprises a conveying opening 42, via which the extraction fluid E is applied to the mixture G in the operating state. The centrifuge assembly further comprises a

Expansion tank 5, wherein in the expansion tank 5, a lower container pressure can be formed compared to the rotary pressure. The

Outlet opening 23 of the centrifuge drum 2 is at one

Receiving opening of the expansion tank 5 is arranged and the offset under the rotation pressure mixture so with the ejection element 4 via the outlet opening 23 in the flash tank 5 from the

Centrifuge drum 2 dischargeable, that the mixture G under the lower pressure vessel of the flash tank 5 explosively relaxed, and thus mechanical can be unlocked. Thus, due to the rapid pressure change from the higher rotary pressure to the lower tank pressure, the mixture, in particular the settleable mixture, can be released explosively. Subsequent to the centrifuge arrangement described above, a further extraction step ES, ES1, ES2 can take place in a series-connected centrifuge Z, Z1, Z2, in that the mixture G is transferred by the discharge device 51 into the subsequent centrifuge Z, Z1, Z2. FIG. 2 shows a schematic representation of another

Centrifuge assembly comprises a centrifuge 1 with a centrifuge drum 2, which comprises an inlet opening 22 and an outlet opening 23, and a hollow cylindrical shape with a conical part 7, in

Moving direction of the mixture G has. An ejection element 4 is arranged in the centrifuge drum 2, wherein the ejection element 4 is preferably arranged at least partially at the outlet opening 23. In addition, the centrifuge assembly comprises an ejection element 4 with a

Conveyor 41. The conveyor 41 is a centrifuge screw 41 1 and comprises a conveying opening 42, via which in

Operating state, the extraction fluid E is applied to the mixture G. Subsequent to the centrifugal assembly described above, a further extraction step ES, ES1, ES2 in a series

switched centrifuge Z, Z1, Z2 take place by the mixture G is transferred by the discharge device 51 in the subsequent centrifuge Z, Z1, Z2.

Figure 3 shows a first embodiment of the inventive

Extraction method in a centrifuge arrangement and can be described as follows. A lignin-containing mixture G becomes a first

Centrifugal Z1 supplied and there is extracted in a first extraction step ES1, an extractant EX1 at a temperature T1 and a pressure p1 from the mixture G and an extract ET1 discharged into a container B1. Subsequently, the lignin-containing mixture G is transferred to a second centrifuge Z2 and there in a second extraction step ES2 an extraction material EX2 at a temperature T2, which is at least 5 ° C higher than the temperature T1, and a pressure p2, which is greater and / or equal the pressure p1 is extracted from the mixture G and an extract ET2 discharged into a container B2. FIG. 4 shows a further embodiment of the extraction process according to the invention in a centrifuge arrangement and can be described as follows. A lignin-containing mixture G becomes a first

Centrifuge Z1 is supplied and is subjected to a digestion A and / or a partial digestion tA in a first extraction step ES1. In this case, the centrifuge Z1 can be a centrifuge according to FIG. 1, in which a mechanical digestion via abrupt relaxation takes place. Subsequently, the lignin-containing mixture G is transferred to a second centrifuge Z2 and extracted there in a second extraction step ES2 more of the extractant EXn. FIG. 5 shows a further embodiment of the extraction method according to the invention in a centrifuge arrangement and can be described as follows. A lignin-containing mixture G is fed to a first centrifuge Z1 and is treated in a first extraction step ES1 with an extraction fluid E, in particular water. Subsequently, the lignin-containing mixture G is transferred to a second centrifuge Z2 and extracted there in a second extraction step ES2 with a solvent L, in particular an organic solvent, the Restlignin.

Claims

claims:

Extraction method for treating a mixture (G) in a centrifuge arrangement, which comprises a centrifuge (Z, Z1, Z2) with a centrifuge drum (2) rotatably mounted about a drum axis (T), which engages with a drum shell (21) from an inlet opening (Z). 22) to an outlet opening (23) along the drum axis (T), wherein on an inner peripheral surface (24) of the drum shell (21) a drum screen (3) is provided, in which an ejection element (4) is arranged, which is a conveyor (41) with a delivery opening (42),

wherein the centrifuge drum (2) in the operating state over the

Inlet opening (22) is supplied to a mixture (G), and the

Centrifuge drum (2) is rotated around the drum axis (T) such that on an inside of the drum screen (3) the mixture (G) under a drum pressure (P) generated by the rotation is deposited,

characterized in that

the mixture (G) is a lignin-containing mixture (G), which is heated to a starting temperature of 100-400 degrees Celsius, and by means of the conveyor (41) in an extraction step (ES, ES1, ES2) an extraction fluid (E) in the form of hot water at one

Extraction pressure of 1 -150 bar and an extraction temperature of 100- 400 ° C so supplied to the centrifuge drum (2) and in such a way via the delivery opening (42) from the conveyor (41) in the

Centrifuge drum (2) is applied to the deposited on the inside of the drum screen (3) mixture (G) that by means of

Extraction fluids (E) lignin and hemicellulose are extracted from the mixture (G).

2. Extraction method according to claim 1, wherein in the centrifuge (Z, Z1, Z2) a first pressure (p1) and / or one of the first pressure (p1)

different second pressure (p2) and / or a first temperature (T1) and / or one of the first temperature (T1) different second temperature (T2) is set.

3. extraction method according to one of the preceding one

Claims, wherein an extract (ET, ET1, ET2) is removed and an extractant (EXn, EX1, EX2) is partially precipitated.

4. Extraction method according to one of the preceding claims, wherein the addition of the extraction fluid (E) in a Kavitationsrotor (R) is made.

5. Extraction method according to one of the preceding claims, wherein at least a first centrifuge (Z1) and a second centrifuge (Z2) are arranged in series, so that the lignin-containing mixture is first subjected to a first extraction step (ES1) in the first centrifuge (Z1), and then from the first centrifuge (Z1) to perform a second extraction step (ES2) of the second centrifuge (Z2) is supplied.

6. Extraction method according to one of the preceding claims, wherein in the second centrifuge (Z2) a higher pressure and / or a higher

Temperatures than in the first centrifuge (Z1) is set.

7. Extraction method according to one of the preceding claims, wherein in at least one of the centrifuges (Z, Z1, Z2), preferably after the

Extraction step (ES, ES1, ES2) an organic solvent (L) that on the inside of the drum screen (3) located mixture (G) is applied to remove a residual lignin.

8. Extraction method according to one of the preceding claims, wherein in one of the centrifuges (Z, Z1, Z2), in particular before the lignin extraction, a

Digestion (A) and / or partial digestion (tA) of the lignin-containing mixture is performed.

9. Extraction method according to one of the preceding claims, wherein in one of the centrifuges (Z, Z1, Z2), an enzymatic treatment, in particular before the lignin extraction is carried out in order to optimize the yield of an extractant (EXn, EX1, EX2).

10. Extraction method according to one of the preceding claims, wherein in at least one of the centrifuges (Z, Z1, Z2) an inert gas atmosphere is generated.

1 1. Centrifuge arrangement for carrying out a lignin extraction method which comprises a centrifuge (Z, Z1, Z2) with a centrifuge drum (2) rotatably mounted about a drum axis (T), which is connected to a drum shell (21) from an inlet opening (22) to a centrifuge Outlet opening (23) along the drum axis (T) extends, wherein on an inner peripheral surface of the drum shell (21) a

Drum sieve (3) is provided, in which a below by rotation generated drum pressure (P) standing mixture (G) is deductible and in which an ejection element (4) is arranged, which is a

Conveying device (41) with a conveying opening (42),

characterized in that

by means of the conveyor (41) an extraction fluid (E) in the centrifuge drum (2) can be fed and the extraction fluid (E) via the delivery opening (42) from the conveyor (41) in the Centrifuge drum (2) on the on the inside of the drum screen (3) deductible mixture (G) can be applied, that by means of the extraction fluid (E) an extractant (EXn, EX1, EX2) from the mixture (G) is extractable.

12. centrifuge assembly according to claim 1 1, wherein the conveying opening (42) of the conveyor (41) along an ejection axis (X) of the conveyor (41) and in particular as a nozzle and / or as a bore is formed.

13. Centrifuge assembly according to claim 1 1 or 12, wherein the centrifuge (Z, Z1, Z2) comprises a heater.

14. Centrifuge assembly according to claim 1 1, 12 or 13, wherein the

Ejection element (4) is an ejection screw (41 1) and / or the centrifuge (1) comprises a flash tank (5).

15. Centrifuge assembly according to claim 1 1, 12, 13 or 14, wherein

at least a first centrifuge (Z1) and a second centrifuge (Z2) are arranged in series.