Reactor apparatus and method for decomposing objects composed of plastic-based composite materials

Abstract

The present invention relates to a reactor apparatus and method for decomposing an object made of a plastic composite material into its individual components by solvolysis using at least one reactor chamber, in which the object can be exposed to a solvent in a supercritical state. The present invention provides at least three pressure chambers arranged in series: a first load lock chamber, a reactor chamber adjacent to the first load lock chamber, and a second load lock chamber adjacent to the reactor chamber, each connected to each other via a movable partition means, which can be moved in each case from an open position in which two of the adjacent pressure chambers are connected to each other to a closed position in which two of the adjacent pressure chambers are fluidically, thermally, and pressure-isolated from each other. The reactor chamber is thermally coupled to a heating system and is fluidly connectable, directly or indirectly, to the first load lock chamber via at least one first line and to a first pressurizable supply line. A solvent can be supplied to the reactor chamber via the first pressurizable supply line. The second load lock chamber element has a second line, which is connectable directly or indirectly to the first load lock chamber. Means are also provided for moving an object or a carrier holding an object from one pressure chamber to an adjacent pressure chamber in a force-based manner when the partition means is moved to the open position.

Description

[Technical Field]

[0001] The present invention relates to a reactor apparatus and method for decomposing objects composed of plastic-based composite materials into their individual components by solvolysis using at least one reactor chamber in which the objects can be exposed to a solvent in a supercritical state.

[0002] When a liquid such as water is heated under pressure, above its critical temperature and pressure, it eventually reaches a so-called supercritical state, characterized by a lower density, a much lower viscosity, and a much higher diffusion coefficient than a true liquid. Water in the supercritical state also has exceptional solvency. To achieve this state, water must have a temperature of at least 374.12°C and be subjected to a pressure of at least 22.1 MPa (221 bar). The unique solvent properties of water in the supercritical state, plus the ease with which the solvent can be removed by reducing the pressure, are of interesting technological importance.

[0003] These unique solvent properties of supercritical water have already been successfully utilized to separate, process, and recycle, for example, hybrid materials or components, especially composite fiber materials based on engineering plastics. [Background technology]

[0004] German Patent Application No. 2016105966 describes a method and plant for recycling carbon fiber-reinforced polymers using water as a solvent in a supercritical state to separate the carbon fibers or carbon fiber mats from their surrounding polymer matrix. Two similar reactors are used to implement the recycling method, with their operation interlocked with each other in the following manner: In the first reactor, already filled with recycled material and charged with a liquid solvent, after corresponding heating to a processing temperature between 374.12°C and 450°C and subjected to a processing pressure between 221.2 bar and 300 bar, the solvent assumes a supercritical state in which it can dissolve the polymer matrix and separate the fiber components through a chemical reaction, while the second reactor is filled with recycled material and charged with a solvent. Both reactors are thermally coupled via a heat recovery system. The heat recovery system utilizes the heat energy of the first reactor, which must be cooled before the recycle process is completed and the purified material can be removed, to heat the second reactor. The purification reaction process takes place in the second reactor after a corresponding further heating and pressure increase to reach the supercritical state of the solvent while the first reactor is cooled, emptied, and therefore filled with fresh recycle material and can be charged with fresh solvent.

[0005] The sequence of the above operating principles of both reactors in series with each other can be continued continuously.

[0006] The fundamental usability of supercritical water to produce fiber reinforced composites in a plastic polymer matrix can be seen in Japanese Patent Publication No. 3134095 and Japanese Patent Publication No. 10-87872.

[0007] U.S. Patent No. 5,233,021 describes a method for extracting pure polymer components from a multicomponent polymer fiber structure, each component having a different melting temperature. The individual components are extracted from the multicomponent structure by sequentially separating the individual components under different temperature and pressure conditions in separate processing chambers using a supercritical fluid.

[0008] U.S. Patent Application Publication No. 2003 / 0129103 discloses a method for separating an electrophotographic carrier composition containing at least a carrier and a toner, the carrier comprising a magnetic core material and a material such as a resin covering the carrier. For the separation, the carrier is treated in water under supercritical, critical, or subcritical conditions to separate the magnetic core material and the resin material from each other. The separated magnetic core material is then collected.

[0009] Japanese Patent Application Laid-Open Publication No. 2013-203826 discloses a method and system for producing recycled fibers. The system includes a reaction vessel for decomposing a fiber-reinforced resin with a supercritical fluid or a critical fluid. Summary of the Invention

[0010] The present invention is based on the object of improving a reactor device and a method for decomposing objects made of plastic-based composite materials into their individual components by solvolysis, in which the objects can be exposed to a solvent in a supercritical state, making it possible to realize energy-intensive processes on an industrial scale with significantly lower energy consumption than previously possible. In particular, it creates the possibility of managing large amounts of objects to be purified, for example in the form of rotor blade parts or fragments arising therefrom, e.g., in the form of bulk material, resulting, for example, from the dismantling of deteriorated wind turbines.

[0011] The solution to this object on which the invention is based is specified in claim 1. A method according to this solution forms the subject matter of claim 14. Features which advantageously improve the inventive concept form the subject matter of the dependent claims and can be found in the following description, in particular with reference to the example embodiments shown in the drawings.

[0012] The present invention is based on the finding that most of the energy consumption is due to the generation of process parameters related to the temperature and pressure in the reactor chamber required for the solvent's critical state. Therefore, it is necessary to use the amount of energy required for the chemical reaction process, particularly in the form of heat energy, as economically as possible in order to minimize any resulting heat energy losses during the reactor chamber filling, reaction process, and emptying. This applies particularly to the recycling of large amounts of recycled materials on an industrial scale, i.e., in the shortest possible time with high separation quality.

[0013] The reactor device according to the present solution according to the features of the preamble of claim 1 provides at least three pressure chambers arranged in series, each connected or connectable to one another via movable partition means that can be moved individually from an open position, in which two adjacent pressure chambers are connected to one another, i.e., can be in releasable fluid communication with one another, to a closed position, in which two adjacent pressure chambers are fluidically, thermally, and pressure-isolated from one another.

[0014] The pressure chambers located outside the serial arrangement in each case serve as load lock chambers and will also be referred to as such in the following, and each have a reactor cover that opens at its end and that can close the load lock chamber in a fluid-tight, thermally insulating and pressurizable manner. The pressure chamber located between both load lock chambers via a partition means in each case serves as a reactor chamber and is thermally coupled to the heating system.

[0015] The at least three pressure chambers arranged in a serial arrangement are hereinafter referred to as the first load lock chamber, the reactor chamber, and the second load lock chamber. Thus, the object to be chemically treated and made of a plastic-based composite material is first introduced into the first load lock chamber by a carrier with the reactor cover open. After the reactor cover is closed, the object undergoes a thermal pretreatment in the first load lock chamber. The carrier holding the object is then moved from the first load lock chamber into the reactor chamber with the partition means open. In the reactor chamber, the object is subjected to the actual chemical reaction process. The chemically treated object then enters the second load lock chamber, where it is cooled before being released from the second load lock chamber as extractables and residual components at the end of the process.

[0016] Optionally, at least one further load lock chamber can be provided on one or both sides of the reactor chamber, in either case in a serial arrangement, but the remaining description will focus on the above reactor apparatus, in either case with three pressure chambers.

[0017] The reactor chamber, which is advantageously identical in shape and size to the first and second load lock chambers except for the thermal coupling to the heating system, is fluidly connectable directly or indirectly to the first load lock chamber via at least one first line. The first and second load lock chambers are also advantageously identical. A first pressurizable supply line also opens into the reactor chamber, via which solvent can be supplied to the reactor chamber as needed.

[0018] Additionally, the second load lock chamber is fluidly connectable directly or indirectly to the first load lock chamber via a second line.

[0019] Finally, means are provided for moving the carrier holding the objects from one pressure chamber to an adjacent pressure chamber in a forceful manner when the partition means is moved to the open position. Although it is assumed below that the objects to be chemically decomposed are suitably arranged in a carrier for controlled transport through the reactor apparatus, it is equally conceivable to omit the carrier and arrange the objects in the individual pressure chambers, for example in the form of divided bulk material.

[0020] The first load lock chamber can be fluidly connected to both the reactor chamber and the second load lock chamber via a first line and a second line, respectively. This allows a significant proportion of heat to be used to preheat the objects to be chemically separated and the solvent present therein. This is due to the controlled and on-demand diversion into the first load lock chamber of the solvent discharged from the heatable reactor chamber, as well as the solvent discharged from the second load lock chamber and from which heat must be released for cooling purposes. Since the preheating in the first load lock chamber of the objects to be chemically separated together with the carrier and the solvent used to wash the objects and the carrier surroundings is substantially based on waste heat from the second load lock chamber and the reactor chamber, the energy input into the reactor chamber required to create a supercritical state of the solvent in the reactor chamber is significantly lower than that of known comparable reactor technologies.

[0021] Furthermore, the reactor apparatus according to the present solution allows for a stepwise unidirectional passage of a carrier filled with the object to be decomposed from the first load lock chamber into the reactor chamber and from the reactor chamber into the second load lock chamber, from which the target components to be chemically decomposed into individual liquid and solid components can be removed together with the carrier. The continuous, stepwise process control resulting from the reactor apparatus allows for the purification or chemical decomposition of fiber-reinforced plastic parts, in particular in the form of planar components or component segments up to bulk materials, in large quantities and with a high throughput per unit time, and is characterized in accordance with the present solution by the following method steps:

[0022] At the beginning of the method, a first carrier containing the object to be chemically treated must be introduced through the open first load lock chamber and the releasably connected reactor chamber. Then, a second carrier, similarly filled with the object to be chemically treated, is introduced into the first load lock chamber. After the partition between the first load lock chamber and the reactor chamber is closed and the first load lock chamber is closed with a reactor cover, a solvent is fed into the reactor chamber and heated therein to a predetermined temperature T1 of up to 320°C. The pressure buildup resulting from the pressurized feeding of the solvent and the heating in the reactor chamber is limited by a controlled, overpressure-limited discharge of the heated solvent from the reactor chamber at a first pressure value p1 of up to 250 bar, preferably 150 bar, and the heated solvent at temperature T1 and pressure p1 is in a subcritical state.

[0023] As the solvent, preferably water is used.

[0024] The subcritical solvent discharged from the reactor chamber in a controlled, overpressure-limited manner is then fed into the first load lock chamber, so that the objects held in the second carrier are preheated in the load lock chamber. Optionally, additional solvent is also fed under pressure into the first load lock chamber.

[0025] Heat treatment continues in the reactor chamber until a temperature T2 of at least 374°C and at most 500°C and a pressure p2 of at least 230 bar and at most 250 bar are reached, at which point the solvent water becomes supercritical. This condition is maintained for a predetermined treatment time t. During this treatment time t, the solvent in its supercritical state can dissolve the object made of plastic-based composite material into its constituent parts. During this treatment, the polymer plastic portion of the object is put into solution by the solvent, while the insoluble solid portion of the object, such as the fiber portion, remains as residual material in the carrier.

[0026] During this time, a temperature T1 of up to 320°C and a load lock chamber pressure p1 of up to 250 bar are established in the first load lock chamber, optionally by the solvent flowing in separately and by the solvent originating from the reactor chamber. In this way, the object located in the first load lock chamber is subjected to the action of the solvent at the process temperature T1 and process pressure p1 in a subcritical state, while the object located in the reactor chamber is subjected to chemical decomposition by the solvent in a supercritical state, i.e., preheating of the object in the first load lock chamber and chemical decomposition of the object in the reactor chamber are carried out simultaneously.

[0027] After a predetermined processing time t, which depends on how long it takes for the objects in the reactor chamber to be completely chemically separated or decomposed into their individual components, the solvent in a supercritical state is discharged from the reactor chamber in a controlled manner and transferred via a line into a second load lock chamber. Then, a second partition separating the reactor chamber from the second load lock chamber is opened, and the carrier with the solid remaining components of the objects is transferred forcefully out of the reactor chamber and into the second load lock chamber with the assistance of a means. After the second partition between the reactor chamber and the second load lock chamber is closed, the preheated solvent in the first load lock chamber is transferred in a controlled manner into the reaction chamber via a line. After this, or chronologically overlapping with this, the first partition between the first load lock chamber and the reactor chamber is opened, so that the second carrier with the preheated objects is transferred into the reactor chamber. After the first partition between the first load lock chamber and the reactor chamber is closed, the preheated solvent is brought to a supercritical state by heating the reactor chamber as in the previous processing step. After the first load lock chamber is emptied, the reactor cover closing the first load lock chamber is opened and a further carrier with the objects to be separated is loaded. After the first load lock chamber is loaded and closed, filling and preheating begins in the first load lock chamber as described above.

[0028] After the solvent, which has been mixed with the dissolved polymer from the plastic portion of the object, is drained from the second load lock chamber, the first carrier holding the remaining undissolved components can be removed from the second load lock chamber.

[0029] After the solvent is drained from the second load lock chamber and before the reactor cover is opened, the first carrier with the remaining components of the object is rinsed with fresh solvent, so that the solvent is preheated due to the residual heat present in the second load lock chamber and can be returned to the first load lock chamber.

[0030] After the initial filling of the empty reactor apparatus, the method according to the present solution thus comprises carrying out three simultaneously operating processing steps during normal processing, namely, thermally pre-treating the object to be reactively processed in the presence of a solvent in a subcritical state, chemically reactively dissolving or decomposing the object in the presence of a solvent in a supercritical state in the reactor chamber, and cooling and rinsing the remaining components of the object and draining the used solvent from the second load lock chamber.

[0031] The energy-related advantages of the method according to the present solution and of the reactor device according to the present solution are, inter alia, the utilization of waste heat from the reactor chamber and from the residual heat of the second load lock chamber for heating the first load lock chamber after the corresponding filling of the object by filling it with a solvent in a subcritical state at a process temperature T1 and a process pressure p1.

[0032] The treatment time or residence time of the objects in the first and second load lock chambers depends on the duration of the chemical reactive decomposition or dissolution treatment in the reactor chamber. With a constant amount of objects per carrier and an appropriate selection of treatment volume in the reactor chamber, the treatment time t for complete dissolution of the plastic part of the objects is typically 2 hours, i.e., the carrier with the objects located in the reactor device is moved through one pressure chamber every 2 hours.

[0033] As a result of the above-described operating principle of the reactor device according to the present solution, the temperature level in the reactor chamber fluctuates only between the process temperature T1, which results in the end-of-process temperature during the heating stage in the first load lock chamber, and the process temperature T2, at which the solvent is in a critical state. Depending on the selection of the upper process temperature T2, which can be between 374°C and 500°C, the temperature in the reactor chamber only needs to be further heated from the lower process temperature of 320°C, ranging from a minimum of 54°C to a maximum of 180°C. The energy input required for each individual decomposition and dissolution process is therefore significantly lower than in all previously known methods of this type. The device according to the present solution, as well as the method according to the present solution that can be implemented therewith, are explained in more detail below with reference to the illustrated exemplary embodiments.

[0034] The invention will now be described by way of example using exemplary embodiments, without limiting the general inventive concept, and by way of reference to the drawings in which: [Brief explanation of the drawings]

[0035] [Figure 1] A p / T graph illustrating the cyclic process of solvolysis is shown. [Figure 2] 1 illustrates an example embodiment of a reactor device formed in accordance with the present solution. [Figure 3] 1 shows the carrier with the object to be treated reactively disposed therein. [Figure 4] A schematic diagram is shown. [Figure 5a] The individual processing steps are shown. [Figure 5b] The individual processing steps are shown. [Figure 5c] The individual processing steps are shown. [Figure 5d] The individual processing steps are shown. DETAILED DESCRIPTION OF THE INVENTION

[0036] Figure 1 shows a thermodynamic pressure-temperature diagram in which the phase transitions of water are shown as a function of pressure and temperature. In addition to the phase transitions, which are known per se, the critical point of water should be noted. Above a temperature of 374.12°C and a pressure of 221.2 bar, the defined state of matter for water no longer exists, in particular because the densities of the liquid and gas phases are identical. It is precisely this critical point that must be reached and exceeded to achieve the desired effect of dissolving plastic-based fiber-reinforced composites.

[0037] The reactor arrangement according to the present solution is constructed in such a way that the thermodynamic cyclic process K shown in Figure 1 can be realized with minimal energy input in the sequence of cyclic stages K1, K2, K3, K4 and K5 shown in the figure. Reference will be made below to the cyclic stages K1 to K5 shown in Figure 1 in conjunction with the description of the method steps given below.

[0038] 2 shows a preferred embodiment of the reactor device according to the present solution, which is formed by three pressure chambers connected to one another in series in the form of a first load lock chamber 1, a reactor chamber 2, and a second load lock chamber 3. All three pressure chambers 1, 2, 3 are preferably in the form of hollow tubes, each having the same internal diameter and chosen to be equal in length. A first partition means 4' is introduced between the first load lock chamber 1 and the reactor chamber 2, and a second partition means 4'' is introduced between the reactor chamber 2 and the second load lock chamber 3, each partition means having a slide valve which, in the open state, allows free movement between the two adjacent pressure chambers, and, in the closed state, separates the adjacent pressure chambers from one another in a fluid-tight, thermally stable, and pressure-stable manner at temperatures up to 650°C and pressures or pressure differences up to 400 bar. The first and second load lock chambers 1, 3 can be closed at their ends by reactor covers 5', 5'', respectively, which allow the first and second load lock chambers 1, 3 to be closed in a fluid-tight manner from the surrounding environment.

[0039] The reactor chamber 2 is also equipped with a heating system H, which allows the reactor chamber 2 to be heated to a processing temperature of up to 500°C.

[0040] A carrier 6 is provided (see FIG. 3 ) to correspond to the inner diameter of the pressure chambers 1, 2, 3, which are identical in dimensions except for the inner diameter. The carrier 6 is suitably designed to receive the object 7 to be chemically dissolved, preferably a fiber-reinforced composite material in the form of fragments or pieces. For this purpose, the carrier preferably has a grid-like holder 8, which allows flow and temperature distribution around the object 7 in all possible directions within the carrier 6. Slide elements 9 attached to the outside of the carrier 6 allow the carrier 6 to easily slide or be pushed through the tubular inner contours of the individual pressure chambers 1, 2, 3, which each have the same cross-sectional shape and size and longitudinal axes that are coaxially oriented with respect to one another. This ensures that the carrier 6 introduced into the reactor chamber 2 via the first load lock chamber 1 can easily enter the reactor chamber 2 and from there into the second load lock chamber 3, from where the carrier 6 can be removed again from the reactor system.

[0041] FIG. 4 shows a schematic overview of all components required for the operation of the reactor system according to the present solution. The first load lock chamber 1 is openably connected to the reactor chamber 2 via a first partition means 4′. The reactor chamber 2 is likewise openably connected to the second load lock chamber 3 via a second partition means 4″, which is otherwise identical to the first partition means 4′. The first and second load lock chambers 1, 3 can be closed fluid-tight at their ends by reactor covers 5′, 5″, respectively. The reactor chamber 2 is thermally coupled to a heating system H, which serves as the only heat source within the entire reactor system according to the present solution. A supply line Z1 opens into the first load lock chamber 1, via which a solvent, preferably in the form of water, can be supplied by a supply pump F, preferably in a pressure-regulated manner, in a controlled manner and as needed, into the first load lock chamber 1.

[0042] Similarly, supply lines Z2, Z3 open into the reactor chamber 2 and the second load lock chamber 3, respectively, via which supply lines a solvent in the form of water can be supplied by respective supply pumps F, preferably in a pressure-regulated manner and as needed, to the reactor chamber 2 and the second load lock chamber 3, respectively.

[0043] Furthermore, a first line A1 leads out from the reactor chamber 2, along which a controllable check valve SP is installed. The first line A1 opens into a buffer reservoir ZW. The buffer reservoir ZW is preferably thermally insulated in order to temporarily store the hot solvent discharged from the reactor chamber 2 in a controlled manner by the check valve SP for further use without the discharged solvent undergoing significant cooling. The buffer reservoir ZW is connected to the first load lock chamber 1 via a supply line Z4, along which a controllable check valve SP is also arranged. In addition, a second line A2 opens into the buffer reservoir ZW and is connected to the second load lock chamber 3, along which a check valve SP is also introduced.

[0044] Additionally, reactor chamber 2 is fluidly connected to first load lock chamber 1 via a third line A3, along which a controllable check valve SP is also disposed. Solvent can thus, in turn, exit reactor chamber 2 via third line A3 directly into first load lock chamber 1 as needed, limiting overpressure buildup in reactor chamber 2 without delay and / or assisting in preheating of the solvent in the first load lock chamber. Additionally, third line A3 allows for the controlled transfer of solvent preheated in first load lock chamber 1 into empty reactor chamber 2, as described in more detail below.

[0045] In a similar manner, a fourth line A4 is attached between the reactor chamber 2 and the second load lock chamber 3, along which a controllable check valve SP is also disposed. The fourth line A4 is used to transfer the supercritical solvent in a controlled manner out of the reactor chamber and into the second load lock chamber 2, as will also be explained in more detail below.

[0046] Finally, a fifth line A5 connected to the collection container AB is drawn out from the second load lock chamber 3, and a check valve SP is arranged along the fifth line A5.

[0047] The above components interact to achieve the process of degrading an object made of a plastic-based composite material as follows:

[0048] Starting from a completely empty reactor system, a first carrier 61 filled with objects to be reactively treated is placed into the reactor chamber 2 via the first load lock chamber 1, which is opened by opening the reactor cover 5', and the partition means 4' between the first load lock chamber 1 and the reactor chamber 2, which has been moved into an open position. The partition means 4' between the first load lock chamber 1 and the reactor chamber 2 is then closed. A second carrier 62, supplied with corresponding objects, is introduced into the first load lock chamber 1 with the reactor cover 5' open, which is then fluid-tightly connected to the first load lock chamber 1. This situation is shown in FIG. 5a.

[0049] Water as a solvent enters the reactor chamber 2 through a supply line Z2 shown in Figure 4, and a supply pump F provided along the supply line Z2 can achieve a water pressure of about 150 bar in the reactor chamber 2. While the solvent water is being supplied to the reactor chamber 2, a heating process by the heating system H begins, and as a result, the temperature in the reactor chamber rises to about 300°C.

[0050] The internal pressure in reactor chamber 2 is limited to a maximum of 250 bar, for example, in a pressure-regulated manner by reducing the water flow via first line A1 and a controllable check valve SP located along line A1. The heated solvent leaving reactor chamber 2 via first line A1 is collected in buffer container ZW and temporarily stored as heated solvent. Further heating and pressure regulation in reactor chamber 2 brings the solvent into a supercritical state, i.e., a temperature of 380°C to 400°C and a process pressure of 230 to 250 bar prevail in reactor chamber 2. In this state, the substance is decomposed into its constituent parts by solvolysis. With reference to the thermodynamic cyclic process according to FIG. 1, this part of the process corresponds to cyclic stage K3 and continues until all of the fiber components have been separated from their surrounding plastic matrix. The solvolysis cyclic stage K3 typically lasts for approximately 2 hours.

[0051] In parallel with this, thermally preheated and temporarily stored solvent is drawn from the buffer reservoir ZW into the first load lock chamber 1. The first load lock chamber 1 is further filled with solvent by a supply unit F to reach a pressure of approximately 150 bar. The temperature inside the first load lock chamber is preheated to a temperature of 300 °C and an internal pressure of up to 250 bar by the solvent temporarily stored in the buffer reservoir ZW and, optionally, via a third line A3 containing solvent originating from the reactor chamber 2. The circulation steps K1 and K2 are thus realized in the first load lock chamber 1 while the circulation step K3, in which the substance to be purified is decomposed into its constituent parts, is taking place in the reactor chamber 2. See FIG. 5b.

[0052] After the chemical decomposition process carried out in the reactor chamber 2 is completed, the solvent, which is in a supercritical state and contains dissolved polymer moieties, is discharged in a controlled manner via the fourth line A4 into the second load lock chamber 3. For this purpose, the check valve SP along the fourth line A4 is opened in a controlled manner. Due to the expansion and pressure drop that occurs when the supercritical solvent enters the second load lock chamber 3, the solvent immediately becomes subcritical. Then, the second partition means 4'' to the second load lock chamber 3 is opened, and the first carrier 61 filled with the residue of the chemically treated object is transferred into the second load lock chamber 3.

[0053] To move the carrier 61 from the reactor chamber 2 into the second load lock chamber 3, means are provided that can move the carrier 61 in a forceful manner from the reactor chamber 2 into the second load lock chamber 3. The means provided for this purpose can comprise an electrically, hydraulically, pneumatically or magnetically powered transport mechanism that transports the carrier 61 in the longitudinal direction of the reactor chamber 2 and the second load lock chamber 3, which are openly connected to each other.

[0054] Alternatively, as shown in FIG. 5c, the entire reactor apparatus can be tilted relative to the horizontal Ho or even moved vertically. In this way, the carrier 61 located in the reactor chamber 2 slides under the force of gravity into the second load lock chamber 3 when the second partition means 4″ is open. Using this gravity-driven transport technique, objects can also be introduced into the pressure chamber without a carrier, for example, in the form of loose bulk material. In this case, the bulk material falls into the next pressure chamber. The solvent flows out of the reactor chamber 2 in a controlled manner through the fourth open line A4 and into the second load lock chamber 3, expanding in the process. Then, the second partition means 4″ closing the second load lock chamber 3 is moved to the closed position, and the reactor chamber 2 is filled in a controlled manner with preheated solvent from the first load lock chamber 1 via the open third line A3. The first partition means 4′ between the first load lock chamber 1 and the reactor chamber 2 is then opened. In this way, the second carrier 62 located in the first load lock chamber passes through the reactor chamber 2 and into the first load lock chamber 1. After the corresponding closure of the first partition means 4' between the first load lock chamber 1 and the reactor chamber 2, the reactor apparatus is returned to its original horizontal position Ho.

[0055] As a result of the rapid displacement of the first carrier 61 and the solvent from the reactor chamber 2 into the right-hand load lock chamber 3, and as a result of the discharge of this solvent via the fifth line A5 into the collection container AB (see FIG. 4), a sudden drop in pressure and temperature occurs in the second load lock chamber 3. This corresponds to the circulation stage K4 in the thermodynamic circulation process K shown in FIG. 1. The first carrier 61 introduced into the second load lock chamber 3 together with the remaining components of the fibrous objects is then cooled by rinsing with fresh water, which is achieved with the help of the third supply line Z3 into the second load lock chamber 3. This cooling corresponds to the fifth circulation stage K5. The solvent introduced into the second load lock chamber 2 by rinsing with fresh water is preheated by thermal contact with the second load lock chamber 2 and the first carrier 61, so that this solvent is transferred via the second line A2 to the buffer reservoir ZW to fill the first load lock chamber 1, which is again filled with the third carrier 63 with the objects to be chemically treated.

[0056] After the corresponding cooling and rinsing of the first carrier 61 located in the second load lock chamber 3, the reactor cover 5 is opened and the carrier can be removed from the second load lock chamber 3. In this way, the residue of insoluble matter located in the first carrier has undergone the entire solvolysis cycle shown in FIG. 1. At the same time, the subsequent solvolysis treatment corresponding to the third cycle K3 is already carried out in the reactor chamber 2, the duration of which is up to 2 hours, corresponding to the time frame for both the residence time of the matter in the first load lock chamber 1, where cycle steps K1 and K2 are carried out, and the residence time of the matter in the second load lock chamber 3, where cycle steps K4 and K5 are carried out. See FIG. 5d.

[0057] Thus, the reactor system according to the present solution allows the thermodynamic cyclic process K shown in Figure 1 to be distributed and simultaneously carried out between the first load lock chamber 1, the reactor chamber 2 and the second load lock chamber 3. In full load operation, the process steps carried out in the individual pressure chambers change over a two hour period.

[0058] In contrast to the illustrated division of the pressure chamber into three, i.e., the first load lock chamber, the reactor chamber, and the second load lock chamber, the reactor apparatus according to the present solution can also be supplemented with further load lock chambers in order to realize thermodynamic transitions with smaller pressure and temperature differences. For example, two load lock chambers can be arranged in series upstream of the reactor chamber. Alternatively or in combination, two load lock chambers can be arranged in series downstream of the reactor chamber. [Explanation of symbols]

[0059] 1. Load Lock Chamber No. 1 2. Reactor Room 3. Second load lock chamber 4' First partition means 4'' Secondary Partition 5', 5'' Reactor Cover 6, 61, 62, 63 Carrier 7 Object 8 Holder 9 Slide Elements H Heating System K thermodynamic circulation process K1, K2, K3, K4, K5 Circulation Stages A1, A2, A3, A4, A5 lines F Supply Pump SP check valve AB Collection Container Z1, Z2, Z3, Z4 supply lines Ho horizontal ZW Buffer Container

Claims

1. A reactor device for decomposing an object (7) made of a plastic-based composite material into its individual components by solvolysis using at least one reactor chamber (R), in which the object (7) can be exposed to a solvent in a supercritical state, at least three pressure chambers (1, 2, 3) arranged in series are provided as a first load lock chamber (1), a reactor chamber (2) adjacent to the first load lock chamber (1) and a second load lock chamber (3) adjacent to the reactor chamber (2), the pressure chambers being connected to one another via openable and closable partition means (T1, T2), which can in each case be moved from an open position, in which two of the mutually adjacent pressure chambers (1 / 2, 2 / 3) are connected to one another, to a closed position, in which two of the mutually adjacent pressure chambers (1 / 2, 2 / 3) are fluidically, thermally and pressure-separated from one another, the reactor chamber (2) is thermally coupled to a heating system (H) and is fluidly connectable, directly or indirectly, to the first load lock chamber (1) via at least one first line (A1) and to a first pressurizable supply line (Z2), through which a solvent can be supplied into the reactor chamber (2); the second load lock chamber (3) has a second line (A2), and the second line (A2) can be directly or indirectly connected to the first load lock chamber (1); A reactor apparatus, wherein when the partition means (T1, T2) are moved to said open position, means are provided for moving said object or a carrier holding said object from one pressure chamber to an adjacent pressure chamber in a force-based manner.

2. 2. The reactor apparatus according to claim 1, wherein the pressure chambers (1, 2, 3) are each tubular, each have the same cross-sectional shape and size, and each have longitudinal axes of the pressure chambers arranged coaxially with one another.

3. 3. The reactor system according to claim 1 or 2, wherein said partition means (4', 4'') each comprise a slide valve.

4. 2. The reactor apparatus according to claim 1, wherein a check valve (SP) is arranged along the first line (A1).

5. 5. The reactor apparatus of claim 4, wherein the check valve (SP) is in the form of an overpressure valve.

6. 6. The reactor apparatus according to claim 1, wherein a buffer vessel (ZW) is arranged along the first line (A1).

7. 7. The reactor apparatus according to claim 1, wherein the first load lock chamber (1) is connectable to a second pressurizable supply line (Z1) through which a solvent can be supplied into the first load lock chamber (1).

8. 8. The reactor apparatus according to any one of claims 1 to 7, wherein a third supply line (Z3) for supplying a solvent opens into the second load lock chamber (3).

9. 9. The reactor apparatus according to claim 8, wherein at least one controllable feed pump (F) is arranged in each case along the first, second and third feed lines (Z1, Z2, Z3).

10. 10. The reactor apparatus according to claim 1, wherein a check valve (SP) is arranged along a fifth line (A5) that opens into the second load lock chamber (3) and is connected to a collection vessel (AB).

11. 11. The reactor apparatus according to claim 1, wherein the means comprises a tilting device for moving the at least three pressure chambers (1, 2, 3) arranged in series from a horizontal position to a position inclined relative to the horizontal, during which the carrier (6) holding the object (7) slides out of one pressure chamber and into an adjacent pressure chamber under the action of gravity.

12. 11. The reactor apparatus according to any one of claims 1 to 10, wherein the means comprises an electrically, hydraulically, pneumatically or magnetically powered transport mechanism, which transports the carrier (6) along its longitudinal axis into two pressure chambers releasably connected to each other.

13. 13. The reactor system according to claim 1, wherein the first and second load lock chambers (1, 3), respectively, are closable at their ends in a fluid-tight, temperature-loadable and pressurizable manner by openable reactor covers (R1, R2).

14. 14. A method for disintegrating an object (7) made of a plastic-based composite material into its individual components using a reactor device according to any one of claims 1 to 13, comprising: a) loading a first carrier (6) holding said objects (7) into said reactor chamber (2) and closing said reactor chamber (2); b) loading a second carrier (6) holding said object (7) into said first load lock chamber (1) and closing said first load lock chamber (1); c) supplying a solvent into the reactor chamber (2) and heating the reactor chamber (2) to a temperature T1; d) limiting the resulting pressure in the reactor chamber (2) to a pressure p1 by overpressure regulated discharge of heated solvent from the reactor chamber (2), the solvent being in a subcritical state at the temperature T1 and the pressure p1; e) supplying the subcritical solvent discharged from the reactor chamber (2) into the first load lock chamber (1); f) increasing the pressure and temperature in the reactor chamber (2) to a temperature T2 and a pressure P2, wherein the solvent is in a supercritical state for a predetermined treatment time t; g) after the treatment time t, moving the first carrier (6) holding the object (7) and the solvent out of the reactor chamber (2) and into the second load lock chamber (3), and discharging the solvent out of the second load lock chamber (3); h) moving the second carrier (6) holding the object (7) out of the first load lock chamber (1) and into the reactor chamber (2); i) loading further carriers holding said objects into said first load lock chamber (1); j) removing the first carrier holding the object from the second load lock chamber (3); k) carrying out method steps c) to j) in the form of a successive stepwise process in which further carriers holding objects are thermally treated for the purpose of solvolysis in all said pressure chambers (1, 2, 3).

15. The subcritical solvent discharged from the reactor chamber (2) is temporarily stored in a buffer storage vessel (ZW), 15. The method according to claim 14, wherein the subcritical solvent discharged from the reactor chamber (2) is supplied into the first load lock chamber (1) by discharging from the buffer storage vessel (ZW).

16. 16. Method according to claim 14 or 15, wherein in conjunction with method step e), a solvent is additionally fed under pressure into the first load lock chamber (1).

17. 16. The method according to claim 15, wherein after the solvent has been evacuated from the second load lock chamber (3) in method step g), the second load lock chamber (3) together with the first carrier (6) holding the object (7) present in the second load lock chamber (3) is rinsed with fresh solvent, and after the second load lock chamber (3) has been rinsed, the heated fresh solvent is transferred to the buffer reservoir (ZW).

18. 18. The method according to any one of claims 14 to 17, wherein water is used as solvent and the following process parameters apply: T1: Maximum 320°C p1: maximum 250 bar, preferably 150 bar T2: 374°C to 500°C p2: 230 bar to 250 bar

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