Apparatus and method for recovering valuable materials

Abstract

A membrane filter press comprising two end elements and a plurality of filter elements, wherein a main space defined by a filter medium from a rear back or filter space is formed between two filter elements and an assigned frame section, at least one filter element formed as a membrane filter element by the two filter elements forming the main space, and having a fluidizable interior defined by at least one flexible membrane in the direction of the filter medium, the main space having at least one supply passage for a mixture of substances to be separated, the back or filter space having at least one filter passage for the filter material, in particular at least one filter passage leading to a collection passage, and the main space having not only a supply passage but also at least one discharge opening, in particular a discharge opening located vertically above the supply passage. The present invention further includes a plant and method for producing solid products and / or valuable materials.

Description

Technical Field

[0001] The present invention relates to a membrane filter press, a plant, and a method for improving the separation of solid products or valuable materials.

[0002] A number of methods and apparatuses for separating solid products and / or valuable materials from auxiliary or by-products in a single-stage or multi-stage processing step downstream of an actual chemical reaction are known in the chemical industry. These generally use filtration or separation apparatuses operating continuously or batchwise.

[0003] Vertical filter presses operating in batch mode or membrane filter presses having filter plates suspended adjacent to one another exhibit high dehumidification rates, and typical embodiments for solid-liquid filtration are known, for example, from German Utility Model No. 20202110189, German Utility Model No. 202018104129, or German Patent Application Publication No. 102015007535. Membrane filter presses comprise up to 200 membrane filter plates arranged parallel to each other between a head plate and an end plate. It is also known to provide plate packages by combining membrane filter plates with rigid filter plates without membranes. Two outer surfaces of the membrane filter plates are provided with flexible or movable membranes, which are driven and restored by, for example, flowing water into the internal space. This step is used to press and dewater the resulting filter cake at the end of the loading stage before the membrane filter press needs to be opened and emptied. The membrane may form a single component integrated with the membrane filter plate, or it may be a replaceable component. The membrane filter press disclosed in German Utility Model No. 202018104129 has a central feed channel, and each plate has a central opening through which the mixture of material to be separated (feed) can flow from one filter space to an adjacent filter space. Four collection channels for discharging the filtrate are formed by channel segments within each plate, which form a common flow channel in the closed structure of the membrane filter press.

[0004] German Patent No. 102007027033 discloses a membrane filter press that enables more extensive processing of a filter cake by rinsing away unwanted substances. For this purpose, the plate has continuous rinsing passages at two plate edges. An introduction element leads from a supply rinsing passage to each filter space, and an discharge element leads to a discharge rinsing passage and exits the filter space without passing through the filter material. Thus, the filter cake can be rinsed, for example, with water or a liquefied medium, and unwanted adhering substances can be discharged.

[0005] In the production process for methionine, which is common knowledge, it is known that the mother liquor from methionine production is discharged and treated using a filtering device through which unreacted liquid substances and inhibitors are removed. The amino acid methionine is used in many fields, such as pharmaceuticals, health and fitness products, but in particular, it is used as a feed additive in many types of livestock feed. On an industrial scale, methionine is produced chemically via the Bucherer-Werkes reaction, a variation of the Strecker synthesis. The starting material 3-methylmercaptopropanal (MMP, produced from 2-propenal and methyl mercaptan), hydrocyanic acid (hydrogen cyanide), ammonia, and carbon dioxide are reacted to obtain 5-(2-methylmercaptoethyl)hydantoin (methionine hydantoin), which is then subjected to alkali hydrolysis with alkali metal hydroxides and / or alkali metal carbonates and alkali metal bicarbonates, such as potassium hydroxide and / or potassium carbonate and potassium bicarbonate, to obtain alkali metal methionates (e.g., potassium methionine) (see Formula 1).

[0006] Formula 1: Saponification of methionine hydantoin [ka]

[0007] The solid product methionine is finally released from its alkali metal salt by acidification, for example by carbon dioxide (carbonation) (see Equation 2), and filtered off as a precipitate from the suspension containing alkali metal carbonates and alkali metal bicarbonates (e.g., potassium carbonate and potassium bicarbonate).

[0008] Equation 2: Carbonation [ka]

[0009] Filtration is carried out continuously, for example, using a separation or filtration unit, where the filtrate and mother liquor (first mother liquor) containing alkali metal bicarbonates (e.g., potassium carbonate and potassium bicarbonate) are recirculated to saponify the methionine hydantoin. Such a process is disclosed, for example, in European Patent Application Publication No. 780370.

[0010] As with all recirculation processes, this process also requires the removal of the filtrate to prevent the individual precursors and by-products, particularly formate, from increasing beyond acceptable levels, as these are inhibitors. However, the removed filtrate still contains methionine, alkali metal carbonates, and alkali metal bicarbonates (e.g., potassium carbonate and potassium bicarbonate), which are useful products for the saponification of methionine hydantoin. To recover as much methionine and potassium bicarbonate as possible from the filtrate, a second carbonation may be performed on the removed filtrate.

[0011] Obtaining methionine and potassium bicarbonate from a first mother liquor by a second carbonation is subject to various processes, such as those disclosed in German Patent Application Publication No. 2421167, in which separation by centrifuge after carbonation is proposed. Alternatively, European Patent Application Publication No. 839804 proposes using a water-soluble liquefaction medium to precipitate methionine, but this involves additional effort and the possibility of impurities.

[0012] Even when the separation apparatus is known and tested, the separation step often requires thorough cleaning of the separation apparatus, which involves a high degree of manual work, especially in separation apparatuses such as filters or membrane filter presses that can achieve particularly high dry values.

[0013] Therefore, an object of the present invention is to provide an improved separation apparatus that enables the achievement of higher performance for plants or methods of solid products and / or solid valuable materials.

[0014] This objective is achieved by a plant for producing solid products and / or valuable materials having the characteristics of claim 1, and by a method for producing solid products and / or valuable materials having the characteristics of claim 10.

[0015] The plant is configured to produce a solid or solidifiable product and / or a valuable material, in particular to produce at least one product and / or at least one valuable material in a mixture of liquid substances, and comprises a process unit and at least one connected separation unit, the process unit is - At least one reactor for precipitating or solidifying valuable materials, - At least one supply conduit to the processor unit and / or reactor for introducing at least one reactant and, if necessary, additional (auxiliary) substances, - A connecting conduit for discharging a suspension containing at least one precipitated solid valuable material as a liquid substance mixture to a separation unit, wherein the connecting conduit is configured to separate the solid valuable material from the suspension. The separation unit comprises at least one membrane filter press, the membrane filter press is • Through conduits to the receiving and conditioning units, • Via return conduit to the process unit It is connected.

[0016] In this specification, “solid products and / or solid valuable materials” are collectively referred to as “valuable materials,” where “valuable materials” means substances or mixtures thereof that have a positive effect on the process when the valuable materials are separated as solids in accordance with the present invention and / or recycled to the upstream processes and / or liquefaction of the plant, unless otherwise specified. In particular, valuable materials are not inhibitors or contaminants and / or are not detrimental to the quality of each process and / or product. In this case, valuable materials may be appropriately selected, for example, from the reactants, by-products, auxiliaries and / or final products of each process for the final product. Products and / or valuable materials are, in particular, chemical substances or mixtures of substances. In this case, “by-products” is also used synonymously with all substances in a mixture of substances that do not constitute solid “valuable materials,” unless otherwise specified.

[0017] In the first embodiment, the receiving and conditioning unit is a heat exchanger or heating device, thereby bringing the liquefaction medium to a temperature at least equal to the melting or dissolution temperature of the solid valuable material, ideally at least 5% higher than the liquefaction or dissolution temperature of the solid valuable material. For the production and liquefaction of methionine, it is advantageous to establish a temperature of 60°C or higher, ideally 70°C or higher.

[0018] The receiving and conditioning unit may also be an adjacent process unit or plant unit from which a suitable liquefied medium can be derived.

[0019] The term “reactants” should be understood to mean all starting materials and auxiliaries, as well as optionally, a flowable catalyst or liquid catalyst, which are collectively referred to as reactants for simplicity. The state of matter generally refers to standard conditions of 1 bar and 20°C, or, unless otherwise indicated, typical process conditions known to those skilled in the art other than those of this invention.

[0020] Furthermore, it should be understood that the numerical representation of a "single (a)" unit, such as a "reactor," may include two or more units and is not necessarily limited to a "single" unit.

[0021] Finally, the term “connected” should be understood to mean not only direct connections, but also conduits or conduit connections to which units secondarily important to the invention are located, such as valve manifolds, stack tanks, or indirect heat exchangers.

[0022] The membrane filter press included in the plant is A filter chamber is formed between two filter elements and an assigned frame section, comprising two end frames, a plurality of filter elements positioned between the end frames, at least one supply passage for a suspension, and at least one collection passage for discharging filtrate, and is divisible into a main space and a rear filtrate space by an insertable filter medium. At least one filter element is formed as a membrane filter element by two filter elements forming a main space and has a fluidizable interior. The fluidizable interior of the membrane filter element may be formed from a plurality of subspaces interconnected via passages or conduits. At least one interior is defined by at least one flexible membrane in the direction of the main space / inserted filter medium. The flexible membrane ideally forms at least one wall or wall portion of the interior and can be moved, stretched, or expanded in the direction of the main space by increasing the internal pressure. The main space has or is connected to at least one supply passage for a mixture of substances to be separated. The back or filter space has or is connected to at least one filter passage for discharging the filter material, where advantageously, at least one filter passage leads to a collection passage, thereby enabling the filter material to be discharged from the membrane filter press. The collection passage is advantageously formed from a number of passage segments, each of which is located within the filter element, together forming the entire collection passage.

[0023] The main chamber includes not only a supply opening but also at least one discharge opening, particularly a discharge opening arranged vertically above the supply passage.

[0024] In other words, it is possible to enable the liquefied medium to directly traverse the main space from the supply opening for the substance mixture to be separated to an additional discharge opening without passing through the filter medium, particularly without passing through the filtrate passage and / or the collection passage for the filtrate. This also distinguishes it from known filter presses or membrane filter presses where the main space containing the formed filter cake can be rinsed by injecting a fluid that is discharged again via a lower rinsing passage, which is not integrated here, for example, via the supply opening or the supply passage through the upper introduction rinsing passage.

[0025] The filter element may in principle have any polygonal, circular or elliptical shape. The filter element preferably has a basic shape of a square, rectangle or at most octagon. The element has a lower frame section, an upper frame section and a lateral frame section. In the case of a square filter element, these are a lower frame section, an upper frame section and two lateral frame sections having a frame or edge region. The membrane filter press and the formed spaces and their flow passages are described based on the position of the filter medium. The membrane filter press operates usefully only when using the filter medium, but the filter medium is a wearing part and generally not part of the membrane filter press.

[0026] The term "frame" or "edge region" should not be understood as being geometrically limited and particularly refers to the region of the filter element that is in contact with an adjacent filter element and / or where the filter medium is fixed.

[0027] The term filter element should be further understood to include, in particular, a group of frame-type or plate-type elements that together form a filter element, and especially a group of elements that are stacked on top of each other parallel to the plane in which the filter material extends, forming a single filter element together, and also having corresponding flow passages, in particular internal flow passages.

[0028] Therefore, for example, two circumferential elements or frames may each have filter media, and the central element may form a dividing and supporting wall, and thus the three elements together form one filter element. Similarly, each circumferential element or frame may have filter media, and the central element may have at least one expandable membrane, which itself does not contain filter media, and the group of elements together form a complete membrane module.

[0029] Further embodiments and further details of the basic configuration of a filter press or membrane filter press, such as external support structures, sealing means, internal geometry, driving means for opening, closing, and pressing the filter elements, membrane filter frames and different arrangements of filter frames, discharge devices, media connection elements to the head plate, etc., are all known, and therefore these embodiments and further embodiments can be expanded and / or combined as desired by those skilled in the art. This also applies to process engineering requirements for operating a filter or membrane filter press. In particular, the head plate / element, which is one of two end elements, includes at least one connection element, such as a flange or abrupt coupling for each (internal) passage or conduit.

[0030] In known methods, the head element is specifically the idle side, while the opposite end element is the movable side, which is motorized to seal and press the membrane filter press.

[0031] In an advantageous embodiment, it may be provided that at least one supply conduit is located in the vertically lower frame section. This has the advantage that, once the feed is introduced, the trapped gas can be released upward, for example, through the discharge opening or filter passage. Furthermore, during the liquefaction step, the filter cake is positioned vertically downward from the introduced liquefied medium, and therefore the discharge opening is kept almost free, allowing for the most vigorous mixing possible between the solid (filter cake / filter cake pieces) and the incoming liquefied medium.

[0032] In a further advantageous embodiment, at least one discharge opening located vertically above the supply passage can therefore be located in the vertically upper frame section.

[0033] Since the liquefied medium must fill the main space which is largely filled with the filter cake, i.e., it will experience high flow resistance, at least temporarily, in a further advantageous embodiment, the number of lower supply or delivery passages may be provided to be at least one greater than the number of outflow / discharge passages.

[0034] It has been found to be particularly advantageous when two lower supply openings and / or supply passages and one upper discharge opening / one upper discharge passage are provided within the filter element.

[0035] Therefore, in a further advantageous embodiment, the ratio of the total flow cross-sections of the supply passage to the total flow cross-sections of the discharge passage is provided to be in the range of 1:3 to 2:1, ideally in the range of 1:2 to 1:1. This allows fresh liquefied medium to flow in at any time without excessive flow resistance, and furthermore, smaller fragments of the filter cake are discharged as solids and, in some cases, completely dissolved during subsequent transport.

[0036] It is advantageous when the separation unit comprises two, three, or four subunits, each having two, three, or four filter devices and / or precipitation reactors and subsequent filter devices connected in series for optimal discharge of valuable material. Depending on the valuable material to be separated, it is possible to connect the filter devices in series such that the fineness increases, i.e., the average mesh size or average pore size decreases, and / or, in particular, to perform multiple precipitation steps and subsequent solid-liquid separations using the filter devices. Depending on the volumetric flow rate being processed, the separation unit may also comprise multiple parallel channels for partial volumetric flows, each separating the valuable material from the respective partial volumetric flow, where it will be apparent to those skilled in the art that each channel for partial volumetric flow may similarly comprise a subunit, a precipitation reactor and / or a filter device.

[0037] In improving the plant, it may be advantageous for the membrane filter press to be configured according to one of the embodiments and / or variations described above.

[0038] This may be particularly advantageous when the final subunit and / or final filter device is a membrane filter press or similar filter press according to the present invention, which can be emptied and / or regenerated using a liquefied medium.

[0039] It may be advantageous when at least two of the flow paths of separation units, each of which carries a partial volume flow, are connected to a common membrane filter press according to the present invention, which can be emptied and / or regenerated using a liquefiing medium. It may be particularly advantageous overall when, among 1 to n filtration or separation devices for valuable materials, the nth filter device along the main processing or main flow direction, i.e., the final filter device, is a membrane filter press according to the present invention. All embodiments and advantages described for membrane filter presses shall also apply to plants in the same or similar ways unless these embodiments and advantages are excluded for physical or chemical reasons, and vice versa.

[0040] In further improvements to the plant, it may be advantageous that the membrane filter press comprises multiple filter elements, each having a main space formed between two adjacent filter elements, and that at least two main spaces are connected to at least one discharge passage of the membrane filter press via their respective discharge openings, and that at least one discharge passage is connected to a process unit, in particular to a reactor of the process unit. The discharge passage is advantageously connected to a container or stack tank located upstream of the process unit.

[0041] The collection conduit is, in particular, an internal collection conduit, where “internal” collection conduit should be understood to mean that the conduit is formed from the passage segments of individual filter elements, and advantageously, each passage segment is an internal component of each filter element.

[0042] The connection between the collection conduit and the process unit or the reactor of the process unit may also be made via a work-up stage, intermediate processing, etc.

[0043] In further improvements to the plant, the supply passages / supply openings to each main space of the membrane filter press are I. In the conduit (outlet channel) for guiding the filtered material of the upstream separation device, II. Outflow paths of process units, especially in flow paths directly connected to flow paths (outflow paths), and / or III. Receiving and conditioning units for supplying liquefied media, particularly in separate receiving and conditioning units It may be advantageous when connected. Here, “separate” should be understood to mean that the unit is not integrated into the main process and is only connected to the main process for the liquefaction / regeneration step of the separation device.

[0044] In alternative form I, in particular, the membrane filter press may be the final filter device of the plant at position n, and the filtrate used as the liquefied medium, and conditioned if necessary, may originate from upstream of the filter device at position n-1. In this case, the number of filter devices n may be 2, 3, 4, or 5 in particular. It may be particularly advantageous when at least one of the filter devices at positions 1 to n-1 is a continuously operating filter or separator.

[0045] In other words, the liquefied medium is, in particular, a suspension, mixture of substances, or filter from one of the following three channels, where, - In Case I, the filtration product from the upstream separation device is optionally used at least partially after additional chemical and / or physical conditioning. - In Case II, at least one separation device of the separation unit from the flow path of the suspension or mixture of substances to the liquefaction of the valuable material is bypassed at least partially or completely. - In Case III, the liquefaction medium is taken out from a separate receiving and conditioning unit for liquefaction.

[0046] A key aspect of variant I may be that a more significant concentration of inhibitors or contaminants that could be detrimental during recirculation to the process unit may have already occurred, and this depends on the specific process.

[0047] Modification form III allows for optimal conditioning and selection of the liquefaction medium, but has the disadvantage of requiring the greatest construction effort. Therefore, providing modification form I for liquefaction has certain advantages because it allows for the direct use of the filtration material, which is already depleted in terms of at least one valuable material, i.e., in terms of overall volume, as the liquefaction medium.

[0048] In variant I or II, the flow path to the regenerated separation device may also be conditioned, for example, by adjusting the temperature for optimal liquefaction.

[0049] In an advantageous configuration of the plant, the plant is used to produce methionine. Precipitation of methionine from a mixture of materials is carried out by carbonation. The plant is advantageously equipped with at least two separation devices, the first of which is advantageously a continuous separation device such as a centrifuge, a rotary vacuum filter device, or a vacuum belt filter device. For the precipitation of valuable materials, it is advantageous when each separation device has a carbonation reactor located upstream of it, particularly a carbonation reactor to which a gas conduit (e.g., for CO2 introduction) is connected into the reactor.

[0050] It is advantageous when the final separation device is a membrane filter press llch configured according to one of the embodiments or variations described above.

[0051] The present invention further relates to a method for producing solid products and / or solid valuable materials using a plant, in particular, for producing at least one product and / or at least one valuable material in a mixture of liquid substances, a. Steps to prepare the process unit and the isolation unit, b. Introducing at least one reactant and, if necessary, further (auxiliary) substances into a process unit to produce and precipitate at least one solid valuable material in a suspension, in particular the step of precipitation downstream of the production / unit and / or downstream of the production (synthesis) site. c. A step of separating at least one type of solid valuable material using at least one separation device in the separation unit and discharging at least one type of by-product, d This includes methods.

[0052] This involves taking the following steps: e. A step of collecting a small amount of at least one separable valuable material as a filter cake in at least one separation device. Collection should be understood here in particular to mean the temporary enrichment, accumulation, or filling of the valuable material inside the separation device by inflow through at least one supply passage. This increases the pressure inside the separation device, particularly inside the main space, while simultaneously discharging the replaced gas and / or filtrate. The filtrate and at least temporarily the gas also pass through their respective filter media and exit the separation device via the filtrate passage, advantageously via at least one collection conduit. The gas may be discharged through other (gas) passages that are temporarily or permanently suitable for it, such as the discharge passage for the liquefied medium, which is empty in this step, as specified below. f. A step of dehumidifying a small amount of at least one valuable material in at least one separation device, which is advantageously carried out to a residual moisture content of at least 60%, and ideally to a residual moisture content of 35% to 10%. Dehumidification may be carried out in one or more stages, and in particular may be carried out mechanically by air pressure and / or by pressure generated by a fluid, by introducing a gas or a gas mixture. Pressure in mechanical dehumidification is advantageously generated by an incompressible medium, in particular by using a liquid that presses a press film in the direction of the filter cake (valuable material). g. A step of liquefying a small amount of at least one valuable material, which has been collected in at least one separation device and solidified as a filter cake inside the separation device, with a liquefaction medium. The term "inside the separation device" should be understood to mean that the valuable material to be liquefied is not discharged, and therefore, furthermore, the separation device is not opened after collection and single-stage or multi-stage dehumidification. The liquefied medium is favorably introduced into the main space of the filter element of the membrane filter press via one or more supply passages and supply openings after complete filling (collection). h. A step of recirculating the liquefied valuable material to a process unit and / or discharging it to a stack tank.

[0053] In this step and alternative variations of the method, the valuable material dissolved in the liquefied medium may be stored at least temporarily in a tank, particularly in an intermediate location, and may be further conditioned if necessary before being introduced to the upstream part of the separation unit, taking into consideration the main production process.

[0054] In alternative embodiments of the method, prior to step f. liquefaction, a step may be taken in which the separation apparatus is opened and the filter cake or portion of the filter cake is discharged, i.e., dropped, by gravity, in particular, as is possible without manual and / or mechanical intervention. In other words, the emptying step in these variations of the method involves incomplete emptying, thus avoiding more manual washing.

[0055] Next, the separation device is closed again and sealed by pressing, and any remaining adhering filter cake or fragments are liquefied. It may be advantageous if, before closing the separation device and liquefying, at least a significant amount of adherings on the sealing surface are removed, for example, using a brush or compressed air.

[0056] In a further improved method variant, the dehumidification of the valuable material is carried out in at least two series-connected separation devices in at least two substeps. - In the first substep, a first small amount of valuable material is separated and dehumidified, and the filtered material separated in the first separation device is sent to the second separation device. - In the second substep, valuable materials present in the filter are separated and dehumidified. It may be provided.

[0057] It may be even more advantageous if the first separation device is a continuously operating separation device, in particular a vacuum filter, such as a rotary drum filter or a belt filter, or a continuously operating centrifuge or another centrifugal separator, and the second separation device is a chamber-type filter press, in particular a chamber-type filter press or a membrane chamber-type filter press.

[0058] In further improved method variations, the dehumidification in the first substep may be performed to a residual moisture content of 60% to 30% in the separated valuable material, and the dehumidification in the second substep may be performed to a residual moisture content in the range of 45% to 10% in the separated valuable material. The specific separation performance is highly dependent on each substance being separated and the separation apparatus. Ideally, the first substep includes dehumidification to a residual moisture content of 60% to 40% in the separated valuable material, and the dehumidification in the second substep is performed to a residual moisture content in the range of 35% to 15%, ideally in the range of 30% to 10% in the separated valuable material.

[0059] It may be advantageous overall when the burden on the filter media due to the passage of the liquefied medium is eliminated. In the improved method variant, it is therefore provided that a pressure rise occurs in the filter chamber or rear chamber during the feeding of the liquefied medium into the main chamber and its discharge through one or more discharge passages. This pressure in the filter chamber or rear chamber should be at least equal to, or slightly higher than, the pressure in the main chamber, and can be caused by the introduction of a fluid, especially a gas. To prevent sedimentation, the fluid is favorably heated, especially to the dominant temperature in the main chamber / temperature of the liquefied medium.

[0060] In a further improved method variant, the liquefaction medium for liquefying the valuable material collected inside at least one separation device may be an acid and / or alkali, in particular, not a mixture of substances, a filter, or a suspension, i.e., an acid or alkali not taken from the plant or process at the upstream part.

[0061] Liquefaction may be advantageous when it involves conditioning the liquefied medium, particularly heating and / or adjusting its pH value. pH adjustment is performed by known methods, such as the addition of an acid or alkali. This is particularly advantageous when the liquefied medium is obtained as a filter from an upstream process stage to a separation unit, and may be advantageous when the filter is conditioned for the purpose of dissolving valuable materials.

[0062] Similarly, it may be advantageous when the filtrate from the first separation apparatus is supplied to a conditioning unit to carry out a conditioning step before being introduced to the second separation apparatus / second separation step, where, for more extensive precipitation of valuable materials and filtrate, - Post-reactions due to the addition of reactants and / or - For example, changing process parameters such as temperature and pressure. It will take place.

[0063] In a further improved method variant, during liquefaction, the valuable material collected (separated) inside at least one separation device may be exposed to a flow of the liquefiing medium from below in the direction of gravity and discharged from each main space and each filter element upward in the direction of gravity and / or above the supply passage.

[0064] The introduction of the liquefied medium is ideally carried out through at least one supply passage for the feed. Conduit connections, ports, connecting elements, valves, etc., may be provided for this purpose.

[0065] It is particularly advantageous that, while the discharge opening remains open, some or a fragment of the valuable material that is optionally dissolved but not yet liquefied falls into the incoming fresh liquefiing medium. In contrast, small fragments of the valuable material that are still solid may be accompanied, although this may be intentional.

[0066] In process development, a sieve or grid structure may be provided inside or upstream of the discharge opening to specify the maximum size of the filter cake / valuable material fragments that can be washed away.

[0067] It is advantageous when the progress of liquefaction is monitored using sensors. This can be done, for example, by measuring flow rate, pressure, pressure difference, vibration, conductivity, capacitive load, or their progress over time. Particularly in batch operations, it is advantageous to be able to determine the end or degree of liquefaction and, consequently, the output of valuable material, and terminate the cycle. Any main chamber or any discharge opening is advantageously equipped with such sensors. This makes it possible to open the separation unit at a defined time and replace individual defective filter elements as needed. This is particularly advantageous because, in contrast to the typical operating mode of membrane filter presses, there is no continuous visual inspection by an operator who manually emptys the filter press.

[0068] A method according to any one of the prior art claims, characterized by being used to produce the solid valuable material methionine and / or methionyl-methionine (methionine dipeptide; met-met).

[0069] The liquefied medium is, advantageously, a mixture of substances from an upstream unit, and in particular, the mixture of substances is a suspension flowing out from a first or second carbonation or a filter from an upstream separation device such as a continuous filter. Prior conditioning may be provided, in particular, consisting of a temperature increase. The temperature of the mixture of substances can be advantageously raised to above 65°C, ideally above 75°C. The temperature of the liquefied medium is 115°C or less, ideally 110°C.

[0070] A membrane filter press and / or plant configured according to at least one of the exemplary embodiments or variations described herein may be provided for the method, which may be advantageous overall.

[0071] All aspects and advantages described above for membrane filter presses or plants shall also apply to methods in the same or similar applications, unless such aspects and advantages are excluded or inapplicable for physical or chemical reasons, and vice versa.

[0072] The present invention will be described below in this specification with particular reference to exemplary embodiments and figures. [Brief explanation of the drawing]

[0073] [Figure 1] This figure shows a first exemplary embodiment as a schematic diagram of the plant and method. [Figure 2] This figure shows further exemplary embodiments as a schematic diagram of the plant and method. [Figure 3A] This is a partial diagram showing an exemplary embodiment for a membrane filter press. [Figure 3B] This is a partial diagram showing an exemplary embodiment for a membrane filter press. [Figure 4A] This is a partial diagram showing a further exemplary embodiment of a membrane filter press. [Figure 4B] This is a partial diagram showing a further exemplary embodiment of a membrane filter press. [Figure 5A] This is a partial diagram showing a further exemplary embodiment of a membrane filter press. [Figure 5B] This is a partial diagram showing a further exemplary embodiment of a membrane filter press. [Figure 6] This is a schematic diagram of different supply routes at end or head elements.

[0074] Figure 1 shows a plant for producing at least one type of solid valuable material or solidifiable valuable material. Plant 100 comprises a process unit 200 having a supply conduit 204 and an outlet conduit 216 for reactants not further specified or distinguished. For work-up of liquid material mixtures, the outlet conduit 216 is connected to a separation unit 300 via a connecting conduit 206. Separation unit 300 comprises a first separation unit 302 and a second separation unit 304. The first separation unit 302 comprises a discharge conduit 318 for valuable materials, in particular solid valuable materials, and a connecting conduit 314 to the second separation unit 304 into which the filtered material from the first separation unit 302 is transported. A receiving and conditioning unit 400 is located within the connecting conduit 314 and upstream of the second connecting conduit 304. The depleted material mixture, for example, the filtrate from the first separation unit 302, can be modified in terms of its chemical and / or physical properties using the receiving and conditioning unit 400 to achieve broader material separation. Further solid precipitation is specifically carried out for this purpose. The second separation unit 304 is connected to the process unit 200 via a (recirculation) conduit 208. A conduit 314 connecting the two separation units 302, 304 includes a bypass conduit 326 that can thereby bypass the receiving and conditioning unit 400.

[0075] A more extensive precipitation of solids may be carried out, for example, by using an indirect heat exchanger to lower the temperature, and depending on the substance, by precipitating crystalline solids. The solids are particularly identical or nearly identical to the solids previously separated in the first separation unit 302. Alternatively, the separation step 400 comprises a feed conduit for reactants and a mixing unit and / or reactor to achieve at least one chemical reaction and precipitation of the substances led to the conduit 314. The solid material precipitated in the flow path from the first separation unit 302 to the second separation unit is particularly identical to the valuable material of the processor unit 200 / the solid material or valuable material separated from the first separation unit 302.

[0076] In the example shown in Figure 2, within the second separation device 304, the suspension is further depleted with respect to valuable material, and the (second) filter is discharged through the conduit 312 and stacked in the container 230. The second separation device 304 is a membrane filter press in which solids are collected and dehumidified in batch operation.

[0077] Following the separation of the solid valuable material by the first separation unit 302 and the discharge of at least one filtrate as a mixture of materials to the second separation unit 304, the first method step includes collecting the settled valuable material in the second separation unit 304 as a filter cake, where further conditioning of the filtrate and precipitation of the solid valuable material are optionally performed beforehand. A further method step includes performing single-stage or multi-stage dehumidification of the separated valuable material in the second separation unit 304, where the sealed filter cake is exposed to gas, particularly air or an inert gas, under high pressure in the filter space and / or main space for a period of time and / or mechanically pressed through a hydraulically operable membrane 360 ​​(Figure 3).

[0078] As a result, valuable materials are released from the attached liquid phase, and therefore, a large amount of harmful by-products and inhibitors are discharged, with the valuable materials having a residual moisture content of 30% to 15%.

[0079] Filtration using membrane filter presses is highly effective, allowing for efficient separation of liquid contaminants or inhibitors from the filter cake. However, emptying a membrane filter press is generally very time-intensive, especially since it requires manual operation. Furthermore, depending on the type of filter cake and / or the mixture of substances present, the mixture or solid filter cake may contain hazardous substances, requiring the membrane filter press to be opened with specific protective measures in place.

[0080] Accordingly, the present invention provides that in a subsequent method step, the membrane filter press is not opened for emptying and regeneration, but rather the liquefaction of the filter cake / solid valuable material is performed by passing the liquefaction medium through the main chamber of the membrane filter press. The medium is advantageously passed through the main chamber of the filter element of the membrane filter press such that the liquefaction medium does not flow through or substantially flow through the filter material.

[0081] The liquefied medium, rich in liquefied valuable material (filter cake), is recycled to the process unit 200 via the conduit 208.

[0082] In the example shown in Figure 1, the liquefied medium is the filtrate from the first separation unit 302, which is led to a conduit 314 and pre-conditioned in the receiving and conditioning unit 400, particularly by raising the temperature so that the collected filter cake is liquefied. After liquefaction inside the second separation unit 304, the filtrate / enriched liquefied medium, which is rich in valuable materials, is recirculated to the process unit 200 via a conduit 208.

[0083] Figure 2 shows a plant and associated processes equivalent to those in Figure 1. The process unit 200 comprises a first reactor 201 and a second reactor 202, where reactants are introduced into the first reactor 201 and at least one reaction or synthesis step is carried out. The second reactor 202 is a precipitation reactor in which, for example, crystallization of a solid valuable material is initiated. Further reactants or auxiliaries may be introduced into the second reactor 202 to carry out precipitation or crystallization, but this is not shown in this case. The plant 100 comprises a central control unit 500 in which different units and devices are connected via control and data lines 210.

[0084] The outflow passage 216 of the process unit 200 is in the form of a continuously operating vacuum filtration unit and is connected via a connecting conduit 206 to a first separation unit 302 which includes a vacuum device 310. The suspension led to the connecting conduit 206 is applied to a belt filter 308 which is continuously recirculated via a coating unit 306, and this belt filter 308 interacts with the vacuum device 310 in a known manner. The separated solid valuable material with a first residual moisture content passes through a transport unit 318 and is collected in a container 320. The filtration from the vacuum device 310 is temporarily supplied to a container 322 via a conduit 314 for subsequent supply to a second discontinuously (batch-operated) separation unit 304. Located downstream of the vacuum apparatus 310 is a reactor 330, to which the reactants are supplied in a manner not further specified, to achieve a more extensive precipitation of the same or different solid valuable material from the material mixture (filtrate) flowing out of the first separation apparatus 302. The reactor 330 downstream of the first separation apparatus 302 generally enhances the precipitation of the same valuable material from the filtrate. As described herein, in the first step of the method, a suspension is supplied to a second separation apparatus 304, which is in the form of a membrane filter press 340, via a conduit 314, and the solid valuable material is collected as a filter cake, followed by dehumidification of the filter cake, as described particularly in relation to Figures 3 to 6.

[0085] Intended to provide a liquefaction medium for liquefying a filter cake in a closed membrane filter press 340, Figure 2 shows a total of three alternative embodiments, of which generally only one is provided permanently.

[0086] I. In a first alternative configuration, the liquefaction medium may be produced via conduit 314 as a conditioned filtrate from the filtrate of the first separator 302, where the conditioning unit 400 substantially consists of a heat exchanger 420 located upstream of the second separator 304. In one variant, a reactor 330 provided for the precipitation reaction is sized and connected so that, during the regeneration period of the second separator 304, the reactor further functions as a pure buffer vessel and / or as part of the conditioning unit 400 for supplying the liquefaction medium required for the liquefaction of valuable materials.

[0087] In this alternative variant, reactor 330 is bypassed for the step of liquefying the filter cake in the second separation unit 304.

[0088] II. A second alternative configuration involves bypassing the first separation unit 302 and directly supplying a small amount of material mixture or suspension from the process unit 200 to the second separation unit 304. For this purpose, a flow path leading to a conduit 314 via an outflow passage 216, a first valve unit 220, a conduit 214 acting as a bypass for the first separation unit 302, and a second valve unit 226 upstream of the heat exchanger 420. In this alternative configuration, the heat exchanger 420 substantially forms the conditioning unit 400.

[0089] Advantageously, a second small amount of material mixture or suspension from process unit 200 is simultaneously supplied to the first separation unit 302, and the filtrate is stacked in a suitable container or reactor until the downstream separation unit 304 is regenerated (emptied) via bypass conduit 214. In particularly advantageous method modes and plant configurations, the main production process of the valuable material does not need to be completely interrupted.

[0090] III. A third alternative configuration includes a completely separate receiving and conditioning unit 400, schematically shown in the lower right of Figure 2 and enclosed by a dashed line. This receiving and conditioning unit 400 can supply the liquefaction medium necessary for liquefying the solid valuable material from the second separator 304, for example, in the form of a pure solvent, such as an alkali or acid, and can condition or meter the solvent as needed. The solvent thus supplied is passed through a supply conduit 314 via a further valve unit 222 upstream of the second separator 304, as shown, here which may be done at different suitable locations upstream of the second separator 304 and / or for direct introduction into the separator 304.

[0091] In Alternative Configuration III, a receiving and conditioning unit 400, which supplies further liquefied medium, is shown schematically in a highly simplified manner. The receiving and conditioning unit 400 includes a receiving tank 410, conduit 412, heat exchanger 422, and valve unit 224, with supply conduits indicated by arrows, as well as optionally transport means and further units not shown. Valve unit 224 is connected via conduit 316 to valve unit 222 located upstream of the second separator 304 (here a membrane filter press 340), where valve unit 222 is integrated into the supply conduit 314 to the second separator 304. Connecting conduits indicated by dashed lines show alternative or additional connecting conduits 414 to further valve units 226 within conduit 314. Through this connecting conduit 414, the liquefied medium from the receiving tank 410 can be introduced together with the material mixture from the conduit 214 or conduit 314 upstream of the heat exchanger 420 on the suction side of the pump 324, mixed, and produce the final liquefied medium.

[0092] The liquefied medium, enriched with a fully or largely liquefied valuable material (filter cake), is passed through conduit 208 to container 232, which is used for stacking and controlled discharge to process unit 200 / second reactor 202 via conduit 212. In an alternative process (not shown), the enriched liquefied medium is introduced at least partially into the first reactor 201.

[0093] The container 322, through which the filtered material from the vacuum device 310 passes via the conduit 314 and is at least temporarily stacked, enables uninterrupted or nearly uninterrupted operation of the process unit 200 and the first separation device 302.

[0094] In further exemplary embodiments (not shown), the separation apparatus 300 comprises one or two (further) subunits downstream of the first filter apparatus 302 and upstream of the terminal (final) membrane filter press 340 in the filter flow path 314, each subunit having, for example, a reactor 330 and at least one precipitation reactor, similar to the filter apparatus. The filter apparatus of the (further) subunits may be a continuously operating filter apparatus, such as a belt or drum vacuum filter, or a centrifuge.

[0095] Figure 3 shows the basic configuration of a membrane filter press 340 in two embodiments in which a second separation device 304 can be configured according to Figure 1 or Figure 2, in two partial figures A) and B) as longitudinal section views. The figures are highly simplified and therefore not shown, for example, media connections of end or head elements, load-bearing structures, driving means, fluid connections or control components, as these are known in principle to those skilled in the art. In both partial figures, the membrane filter press 340 is shown in an open position in which the membrane filter frames 370 are arranged apart from each other. Partial figure A) shows a membrane filter press 340 having two edge or end elements 342, with only the membrane filter frame 370 positioned between the two edge or end elements 342 as filter elements 344.

[0096] Both embodiments include a central feed passage 364 for the mixture of materials to be separated (feed), and collection passages 366 for the discharge of filtered material are located at the upper and bottom corners of the filter element 344. Since the membrane filter press 340 and the individual filter elements 344 can be oriented and operated as a whole at any desired inclination or orientation, indications such as “upper,” “upper,” “bottom,” or “downward” are used for simpler description and relate to typical and advantageous orientations and setups without being intended as general limitations. In this case, the membrane filter frame 370 and the (rigid) filter frame (without membrane) 372 are shown collectively as filter elements 344. Indications relating to the filter frame 372 also apply to their interaction with edge or end elements 342 and adjacent filter elements 344.

[0097] Unlike in Part A), the membrane filter press 340 in Part B) is formed from filter elements 344, which alternately have membrane filter frames 370 and filter frames 372 in addition to two edge or end elements 342. All filter elements 344, 370, and 372 are oriented in a vertically suspended manner.

[0098] The filter elements 344, 370, and 372 have a filter medium 354 on both sides, which is configured as a filter fleece or filter mat. In the shown embodiment, the filter medium 354 is formed from two parallel filter mats connected via a tubular section in a manner not further specified. When installed, this tubular section bridges the central feed opening 374 of each of the filter elements 344. Two filter elements 344 / a pair of end elements 342 and adjacent filter elements 344 form a common main space 352, in which the mixture of material to be separated (feed) is introduced through the uninterrupted feed passages 362 and feed openings 374 within each filter element 344, in which a filter cake is formed during the collection process. In the left-hand end element 342, also called the head element, the feed passage 362 is simultaneously the feed opening to the subsequent main space 352.

[0099] As viewed from the main space 352, the rear of the filter media 354 is formed into individual filter media spaces or rear spaces 356, from which one or more filter media passages 364 lead to one of the four collection passages. The filter media is discharged via an end element 342 (head element) shown on the left side, which also feeds the material mixture.

[0100] According to the present invention, two discharge openings 376 are provided in each main space 354, thereby discharging and supplying the liquefied medium and the liquefied valuable material to the downstream processing unit 200. Each discharge opening 376 is connected to a discharge passage 378, which is further connected to a return conduit 208 shown in Figures 1 and 2.

[0101] Therefore, when the membrane filter press 340 is regenerated after filling, a short-circuit flow of the liquefied medium can be generated, which, via the supply passage 362, reaches the discharge opening 376 through the supply opening 374 and each main chamber 352 within each filter element 344, and enters the common discharge passage 378.

[0102] Exemplary Embodiments In the method for producing methionine (MET) described at the beginning, in the configuration of the present invention, saponification of methionine hydantoin is carried out in reactor 201 according to formula 1.

[0103] Subsequently, in reactor 202, methionine is liberated from its alkali metal salt by carbonation with carbon dioxide according to the second formula, and filtered as a solid in the first filter device 302 from the mixture of substances containing alkali metal carbonates and alkali metal bicarbonates (e.g., potassium carbonate and potassium bicarbonate).

[0104] Prior to the first carbonation, the mixture of substances in the supply conduit 204 still contains 119–151 g / kg of active potassium cations (a.K+) in the form of, for example, KHCO3, K2CO3, and 7.1–9.0 g / kg of formate as the potassium salt of formic acid. Formate is an inhibitor or contaminant of the methionine process, and it is advantageous to remove it as completely as possible.

[0105] After the first separation apparatus 302, the filtrate has concentrations of 61.5–78.5 g / kg of a.K+ and 8.8–11.2 g / kg of formate, and is subsequently thermally concentrated in an evaporator (not shown). Thus, when the mixture of substances enters reactor 330, it has concentrations of 114.5–145.5 g / kg of a.K+ and 15.8–20.2 g / kg of formate.

[0106] Finally, the valuable materials methionine, potassium carbonate, potassium bicarbonate, and some of the by-products, such as methionyl-methionine (met-met), are filtered out in a second separation apparatus to obtain a high-concentration product.

[0107] The plant for methionine production is configured according to Figure 2 and may include further subunits comprising a precipitation reactor and a filtration device.

[0108] In this way, the valuable materials methionine, potassium carbonate, potassium bicarbonate, and the by-product met-met, which have been thoroughly depleted, can be recycled in liquefied form through the conduit 208 without any adverse effect on the process unit 200.

[0109] By eliminating the need to open, wash, and reseal the terminal second separation device 304, which is configured as a membrane filter press, a significant improvement in the overall performance of the methionine production method was achieved.

[0110] The low complexity of the apparatus is achieved particularly by omitting a separate process unit for the removal and discharge of the filter cake, which would otherwise need to be encapsulated and carried out to avoid condensate formation and the introduction of odors into adjacent plants. Furthermore, mechanical wear on the components of the filter press is reduced because the very frequent movement of plates in each filtration cycle is eliminated. The transport of plates in the filter press can be largely eliminated. Finally, the filter fabric is also protected, extending its service life and significantly minimizing clogging of the filter media. Figure 4 shows alternative embodiments of the membrane filter frame 370 (partial figure A) and the assigned filter frame 372 (partial figure B) in two partial figures A) and B), where the desired vertical orientation is shown. Unlike the earlier embodiment in Figure 3, the supply passage 362 / two supply passages 362 are located in the lower frame section 346, and the discharge passage 378 is located in the center of the upper frame section 348. For the introduction of the suspension from the feed passage 362, the filter frame 372 has shaft-shaped or slot-shaped feed openings 374 and corresponding discharge openings 376, respectively. These feed openings 374 and discharge openings 376 allow the respective material mixtures to pass over the edges of each filter medium 354. In one embodiment not further specified, the feed openings 374 and discharge openings 376 are in the form of fully or partially closed shaft or passage elements that extend from the feeder passage 362 over the edges of the inserted filter medium 354 and provide further securing of the filter medium 354 by, for example, clamping. The operation of the membrane filter press 340 according to the embodiment in Figure 4 or Figure 5 is described in detail with reference to Figure 6.

[0111] Figure 5 shows a membrane filter press 340 similar to that in Figure 4. As shown in Figure 4, the main space 352 is formed on one side by a membrane filter frame 370 (partial figure A) and on the other side by a rigid filter frame 372 (partial figure B), both shown in the open position. The main space 352 has a basic octagonal shape. Two segments of the supply passage 362 are located in the lower frame section 346, and the discharge passage 378 is provided in the upper frame section 348. In addition, several filter passages 364 protrude from the main space 352 and are connected to one of the collection passages 366 for the filtered material. Each supply opening 374 leads from each of the supply passages 362 to the main space 352. Similarly, a discharge opening 376 leads from the main space 352 to the discharge passage 378. These supply openings 374 and discharge openings 376 may be configured as described in relation to Figure 4.

[0112] A common feature of the embodiments shown in Figures 4 and 5 is that both the suspension (feed) to be filtered and the liquefaction medium are introduced through the lower supply passage 362.

[0113] The advantages of this embodiment shown in Figures 4 and 5 are, in particular, that when the liquefied medium is introduced into the main space 352, a defined flow is formed and fragments of the filter cake fall toward the incoming fresh liquefied medium. Smaller fragments are sieved by the upward flow and are accompanied when they reach a sufficiently small size.

[0114] Figure 6 shows the end elements 342 of the membrane filter press 340, as well as all the supply and discharge options for different media. Figure 6 will be helpful in illustrating the individual method steps for operating the membrane filter press 340, which will be described in detail below herein.

[0115] Starting with an empty membrane filter press 340: (1) Introduction of suspension S from below through two supply passages 362, where simultaneously, the trapped gas A, generally air, is released through the upper collection passage 366 and / or a separate venting conduit, where the discharge passage 378 is closed until the main chamber 352 is completely filled (not shown). The discharge passage 378 may be temporarily used to discharge gas A. (2) Further introduction of the suspension S into the main space via the supply passage 362, and first compression of the filter cake by the incoming suspension S, where the filtered material FT is discharged via the collection passage 366. (3) Complete filling of the main space 352 with the filter cake and completion of the introduction of the suspension S, introduction of gas A into the main space 352 via the upper collection passage 366 for more extensive dewatering of the filter cake and discharge of the filtrate FT via the lower collection passage 366. (4) Introduction of fluid, in particular water (indicated as double arrow B) into the interior of the membrane filter frame 370 via a port 380 which may also be located on the upper side, and compression and final dewatering of the filter cake, where the compression of the filter cake and resetting of the membrane create a flow path or flow slot in the main space 352 between the (recovered) membrane and at least one side of the filter cake. (5) Introduction of a liquefied medium VM without valuable materials from below through two supply passages 362 and discharge of a liquefied medium VM+ containing valuable materials through an upper discharge passage 378 until the filter cake is completely liquefied / small enough fragments can be discharged. (6) Introduction of gas A, particularly compressed air (indicated by double arrows), into the main chamber 352 via the upper collection conduit 366, and optional shutoff of the upper discharge passage 378. Introduction of gas A in counterflow via the supply passage 362 and discharge of the waiting liquefied medium VM+ containing valuable materials by increasing the pressure in the main chamber 352 until the liquefied medium VM+ containing valuable materials is completely replaced. In this case, the replaced liquefied medium VM+ may be collected in a container, e.g., a container of the receiving and conditioning unit 400. Purification or filtration of the discharged gas A as necessary, if the discharged gas A contains, for example, volatile parts or hazardous substances of the liquefied medium VM. (7) In particular, the introduction of the suspension S by step (1) without opening the membrane filter press first.

[0116] The opening and closing of the passages during operation and non-operation were not performed separately, but are equally obvious to those skilled in the art from the desired flow control / direction described.

[0117] In this invention, the terms "suspension" and "mixture of substances to be separated" are used synonymously.

[0118] In this invention, the term “liquefiing medium” particularly refers to a mixture of substances, a suspension, or a filter, or to an acid or alkali used for the purpose of liquefying a solid valuable material, and optionally conditioned for that purpose. Furthermore, the term “suspension” should be understood to mean a heterogeneous mixture of a (continuous) fluid and a (dispersed) solid dispersed therein. [Explanation of symbols]

[0119] 100 plants 200 process units 201 Reactor 202 Reactor 204 Supply conduit 206 Connecting conduit (to 300, 302) 208 Return conduit (from 304 to 200) 210 Data Lines 212 Return conduit (from 232, 208 to 200) 214 (Regeneration) Conduit 216 Outflow channel 220 Valve Unit 222 Valve Unit 224 valve unit (from 400) 226 Valve Unit 230 Container 232 Container 300 Separation Units 302 Separation device, 1st 304 Separation device, 2nd 306 Coating Unit 308 Conveyor unit, belt filter 310 Vacuum equipment 312 Emissions (from 304) 314 Conduit (from 302, 310 to 304) 316 Conduit (from 400 to 304 via 222) 318 Discharge (from P of 302) 320 container 322 Container 324 Conveying means, pumps 326 Bypass conduit 330 reactors 340 Membrane filter press 342 Edge / End elements 344 filter elements 346 frame divisions, lower side 348 frame divisions, upper side 350 frame divisions, lateral 352 Main Space 354 Filter media 356 Filtrate / rear space 358 Internal 360 membrane 362 Supply passage (from S) 364 Filter passage (for FT) 366 Collection Passage (for FT, 364) 370 Membrane Filter Frames 372 filter frames 374 Supply opening (to 352 in the filter frame) 376 Discharge opening (for S) 378 Discharge passage (for S after 376) 380 ports (for B deployment) 400 Receiving and Conditioning Units 410 (receiving) tank 412 Conduit 414 Connecting conduit 420 heat exchanger 422 Heat exchanger 500 control units A Fluid 1: Gas, air B Fluid 2: Water E. Reactants FT filter media G Gravity direction S suspension VM liquefaction medium VM+ liquefied medium, containing valuable materials

Claims

1. A plant (100) for producing at least one product and / or at least one valuable material, comprising a first process unit (200) and at least one connected separation unit (300), wherein the process unit (200) is A reactor (201, 202) for processing a mixture of materials, At least one supply conduit (204) for introducing at least one reactant into at least one reactor (201, 202), A connecting conduit (206) for discharging a suspension containing at least one precipitated solid valuable material to the separation unit (300), wherein the separation unit (300) is configured to separate the at least one valuable material, and the connecting conduit (206) and In a plant (100) equipped with, The separation unit (300) comprises at least one membrane filter press (340), and the membrane filter press (340) is Conduits (214, 314) to a receiving and conditioning unit (400) configured to condition a liquefaction medium for liquefying at least one of the aforementioned valuable materials, and A return conduit (208) leading to the process unit (200) recirculates at least one of the liquefied valuable materials. connected A plant (100) characterized by the following features.

2. The membrane-type filter press (302) comprises two end elements (342) and a plurality of filter elements (344), and the filter space, which can be divided by the filter material (354) into a main space (352) and a rear back or filter material space (356), is formed in each case between two filter elements (342, 344, 370, 372) and an assigned frame section (346, 348, 350), and at least one filter element (344) is one of the two filter elements (344) that form the main space (352). Formed as a membrane filter frame (370), comprising a fluidizable interior (358) defined by at least one flexible membrane (360) in the direction of the filter space, the main space (352) having at least one supply opening (374) for the mixture of substances to be separated, in particular a supply opening (374) leading to a supply passage (362), and the back or filter space (356) having at least one filter passage (364) for the filter material (FT), in particular at least one filter passage (364) leading to a collection passage (366), The main space (352) includes not only the supply opening (374) for the material mixture, but also at least one discharge opening (376), in particular a discharge opening (376) located vertically above the supply passage (362). The plant according to claim 1, characterized in that

3. The plant according to claim 1 or 2, wherein the membrane filter press (340) comprises a plurality of filter elements (344), and in each case a main space (352) is formed between two adjacent filter elements (304), and at least two main spaces (352) are connected in each case to at least one discharge passage (378) of the membrane filter press (340) via one discharge opening (376), and the discharge passage (378) is connected to the process unit (200).

4. The supply passage (362) and the connected main space (352) of the membrane filter press (340) are I. In the conduit (314) for guiding the filtered material of the upstream separation device (302), II. Through the flow paths (214, 314) to the outflow path (216) of the process unit (200), and / or III. In the receiving and conditioning unit (400) for supplying the liquefied medium The plant according to any one of claims 1 to 3, characterized in that it is connected.

5. The plant according to any one of claims 1 to 4, characterized in that the separation unit (300) comprises two, three or four filter devices (302, 304) and / or two, three or four subunits each comprising a precipitation reactor (330) and a subsequent filter device (304).

6. The plant according to any one of claims 1 to 5, characterized in that at least one supply passage (362) is located in the vertically lower frame section (346).

7. The plant according to any one of claims 1 to 6, characterized in that at least one discharge opening (376) located vertically above the supply passage (362) is located in the vertically upper frame section (348).

8. The apparatus according to any one of claims 1 to 7, characterized in that the number of lower supply passages (362) is at least one greater than the number of discharge passages (378) arranged above.

9. The apparatus according to any one of claims 1 to 8, characterized in that the ratio of the total flow cross-sections of the supply passage (362) to the total flow cross-sections of the discharge passage is in the range of 1:3 to 2:1, ideally in the range of 1:2 to 1:

1.

10. A method for producing at least one solid product and / or a solid valuable material within a plant (100), a. A step of preparing a process unit (200) and a separation unit (300), b. A step of introducing at least one reactant into the process unit (200) to produce at least one solid valuable material and by-products in the material mixture, c. Separating the solid valuable material using at least one separation device (302, 304) within the separation unit (300) and discharging at least one by-product, In a method including, d. A step of collecting at least one small amount of separable valuable material as a filter cake in at least one separation device (302, 304), e. A step of dehumidifying, in particular multi-stage dehumidification, a small amount of at least one of the valuable materials in at least one separation device (302, 304), f. A step of liquefying at least one small amount of the valuable material collected in the separation device (302, 304) and solidified as a filter cake inside the separation device (302, 304) with a liquefaction medium, g. A step of recirculating the liquefied medium containing the dissolved valuable material to the process unit (100) and / or discharging it to the stack tank (232), A method characterized by including

11. The dehumidification of the valuable material is carried out in at least two substeps within at least two series-connected separation devices (302, 304). In the first substep, a first small amount of the valuable material is separated and dehumidified, and the filtrate (FT) separated in the first separation device (302) is sent to the second separation device. In the second substep, the valuable material present in the filtrate (FT) is separated and dehumidified. The method according to claim 10, characterized in that...

12. The method according to claim 11, characterized in that the dehumidification in the first substep is carried out until the residual moisture content in the separated valuable material is reduced to 30%, and the dehumidification in the second substep is carried out until the residual moisture content in the separated valuable material is 30% or less.

13. The method according to any one of claims 10 to 12, characterized in that the liquefaction medium for liquefying the valuable material collected inside the at least one separation device (302, 304) is a mixture of materials, suspensions and / or filters, in particular a conditioned mixture of materials, suspensions and / or filters from an upstream portion of the plant and / or a preceding method step.

14. The method according to any one of claims 10 to 13, characterized in that the liquefaction medium for liquefying the valuable material collected inside the at least one separation device (302, 304) is an acid or alkali, which is neither a mixture of substances from the upstream portion of the plant and / or a preceding method step, nor a suspension and / or a filter.

15. The method according to any one of claims 10 to 14, characterized in that, during liquefaction, the valuable material collected (separated) inside the at least one separation device (304) is exposed to a flow of the liquefaction medium from below in the direction of gravity and is discharged from each main space (352) and each filter element (344) upward in the direction of gravity and / or above the supply passage (362).

16. The method according to any one of claims 10 to 15, characterized in that the plant (100) for producing at least one product or valuable material is configured according to any one of claims 6 to 10.

17. The method according to any one of claims 10 to 16, characterized in that it is used to produce the solid valuable material methionine and / or methionyl-methionine.

18. At least two precipitation steps, At least two separation steps, The following steps are performed, and prior to the at least two separation steps, a precipitation step is performed for at least one valuable material methionine, and at least one of the precipitation steps, in particular both precipitation steps, is followed by a carbonation step, in particular CO ２ This is a carbonation process using The method according to claim 17, characterized in that

19. The method according to claim 17 or 18, characterized in that the final separation step for at least one valuable material methionine is performed using a plant (100) according to any one of claims 1 to 9, comprising a separation device (304) configured as a membrane filter press (340), wherein after dehumidification, the membrane filter press (340) is emptied and / or regenerated by liquefaction of the filter cake, in particular by emptying and / or regenerating with a closed membrane filter press (340), and after liquefaction of the filter cake, the liquefied medium containing the valuable material is discharged through at least one internal discharge passage (378) of the membrane filter press (340).

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