Pre-processing reactor for a recycled polymeric feedstock processing device and a device comprising said reactor

Abstract

A pre-processing reactor for a recycled polymeric feedstock processing device comprises a screw conveyor (31) in a closed tube (32) with a. halogen discharge pipeline (35), The screw conveyor (31) may have a variable pitch, A heating system comprises an electric heating member (34) connected to a temperature sensor (33) to provide a defined chemical-physical state of the prepared polymeric feedstock in an outlet opening of a pre-processing reactor (3). A heat exchanger (36) connected to an outer chamber (42) of a main reactor (4) via an exhaust gas path (11) may also be used. In the device, the heated multi -jacketed main reactor (4) is downstream of the pre-processing reactor (3) and comprises an inner chamber (41) and an outer chamber (42). The inner chamber (41) is provided with a solid residue conveyor (5) and a steam -and-gas mixture discharge (18) connected to a separator (8). A condensation block (19) and a separation tank (9) for separating the liquid and gaseous fractions of the finished product are downstream of the separator (8). The device is capable of producing a liquid hydrocarbon mixture free of halogens and their acids.

Description

[0001] Pre-processing reactor for a recycled polymeric feedstock processing device and a device comprising said reactor

[0002] Technical Field

[0003] The proposed invention falls within the field of devices for processing waste polymeric material by means of thermal-catalytic decomposition of molecular chains. It can be used for production of liquid hydrocarbon mixtures from mixed polymeric, for example rubber, waste.

[0004] Background of the Invention

[0005] Wastes containing polymeric materials are processed as recycled polymeric feedstocks. The chemical-physical decomposition of their long molecular chains produces a liquid hydrocarbon mixture that has further uses.

[0006] Document CZ 2017-601 describes a device for production of aromatic hydrocarbons by molecular destruction and reforming of polymers. The device comprises a reactor with an inlet zone and a thermal zone. The thermal zone is formed by a pre-processing thermal zone, a molecular destruction zone, and a reforming zone. At least the pre-processing thermal zone and the molecular destruction zone are provided with a heating system. The inlet zone of the reactor is cooled and / or thermally isolated from the thermal zone of the reactor, The inner cross-section of the inlet zone and the pre-processing thermal zone increases in the direction from the press and / or hopper opening towards the molecular destruction zone. At least the molecular destruction zone is provided inside with a screw conveyor to transport solid residues from the molecular destruction zone to the cooled conveyor system. The cooled conveyor system is adapted to prevent the penetration of the hydrocarbon steam-and-gas mixture into the air and vice versa. A rectification block with an adjustable temperature mode is connected to the reactor above the reforming zone. The rectification block is in the upper part provided with at least one steam-and-gas mixture discharge at a predefined temperature. This discharge is connected via a compensation coupling to the upper part of a downstream cooling tower, the bottom end of which is provided with a siphon passage.

[0007] The document CZ 35104 U1 describes an assembly of a device for converting high-molecular, in particular polymeric, waste into process gas, liquid hydrocarbon fraction, and solid carbonaceous residue. It can be utilized for the production of a liquid hydrocarbon mixture of C6-C30 fraction with a significant aromatic content (synthetic oil) by the thermal cracking method and the combination-'recombination of free split hydrocarbons and their radicals in the process of reforming high-molecular organic feedstock using the reactive distillation method. The assembly comprises a pre-processing chamber for preheating the inlet feedstock, where the pre-processing chamber is composed of a hollow vessel of a substantially cylindrical shape, the longitudinal axis of which forms an angle of 5 to 45°, preferably 10 to 25°, with the horizontal plane. The pre-processing chamber rises from the inlet thereof, by which it is connected to the hopper, towards its outlet. The pre-processing chamber is designed to homogenize the inlet feedstock, to mix it with an optional catalyst / neutralizer (in the case of unsorted plastics) and to remove the entrained air. For this purpose, a screw conveyor is coaxially placed inside the pre-processing chamber, which moves the inlet feedstock from the inlet of the pre-processing chamber to its outlet while being simultaneously heated and mixed. At the same time, the pre- processing chamber is provided in its upper area with an air discharge device.

[0008] A disadvantage of the described devices is the contamination of the resulting hydrocarbon mixture by halogens or acids formed therefrom. The acids are formed already in the reactor during the depolymerization of polymers. In addition to degrading the resulting hydrocarbon mixture, the acids also have a corrosive effect on the inner environment of the device.

[0009] Summary of the Invention

[0010] The essence of the in vention is a pre-processing reactor structure that can be used in a recycled polymeric feedstock processing device. A related invention is a recycled polymeric feedstock processing device structure that utilizes this pre-processing reactor. The recycled polymeric feedstock is mainly scrap plastic, rubber (including tires), etc.

[0011] The pre-processing reactor comprises a screw conveyor in a closed tube. The tube is provided with an inlet and an outlet opening for the processed polymeric feedstock. The inlet opening is preferably located in the front part of the tube (relative to the movement of the processed polymeric feedstock from the front to the rear part of the tube) and the outlet opening is in the opposite, i.e. rear, part of the tube. The inlet and outlet openings are preferably radially oriented. For an easy gravitational movement of the polymeric feedstock, it is preferable if the inlet opening is oriented upwards and the outlet opening downwards. The tube is provided with a halogen discharge pipeline in the last 1 / 3 of the effective length of the screw conveyor. Since halogens are a part of the formed hot steam-and-gas mixture, the pipeline for their discharge is usually situated vertically upwards. The halogens are preferably discharged into a neutralization device.

[0012] The effective length of the screw conveyor is that part of its length which actively participates in the movement of the polymeric feedstock through the pre-processing reactor during rotation. The effective length of the screw conveyor thus comprises its length from the inlet of the polymeric feedstock to the screw conveyor, including the part of the screw conveyor that overlaps the cross-section of the inlet opening, For the purposes of this application, the effective length of the screw convey or ends at the closer (front) edge of the outlet opening from the pre- processing reactor and does not overlap it. This is because the outlet opening is preferably oriented vertically downward, where the polymeric feedstock continues by gravity without the need to be actively conveyed by the screw of the screw conveyor (it may alternatively be pushed by the polymeric feedstock that is still being transported to the outlet opening by the screw conveyor). The screw of the screw conveyor may overlap the outlet opening, but it is not comprised in the above definition of the effective length of the screw conveyor.

[0013] The pre-processing reactor is provided with a heating system for the mechanical-thermal- chemical preparation of the polymeric feedstock. In the last 1 / 5 of the effective length of the screw conveyor, the heating system comprises at least one electric heating member connected to at least one temperature sensor. The technical effect of this configuration is to provide a defined chemical-physical state of the prepared polymeric feedstock at the outlet from the pre- processing reactor. The temperature sensor continuously measures the temperature of the prepared (preheated) polymeric feedstock. It is because it is essential that a temperature is reached which allows the release (isolation) of halogens from the polymeric feedstock and their safe removal from the device. In the event that a sufficient temperature is not reached at the temperature sensor, the associated at least one heating member sufficiently increases the temperature of the polymeric feedstock prior to the exit thereof from the pre-processing reactor. A sufficient temperature of the polymeric feedstock for the release of the halogens is thus achieved with certainty.

[0014] The heating system of the pre-processing reactor preferably comprises a heat exchanger. The heat exchanger is a closed body provided with an inlet and outlet opening. At least a part of the outer surface of the tube of the screw conveyor extends into the inner space of the heat exchanger. This ensures the transfer of thermal energy from the inner space of the heat exchanger to the tube of the screw conveyor. The inner volume of the heat exchanger is separated from the inner volume of the tube of the screw conveyor. The heating of the pre- processing reactor can thus at least partially provide hot gas (for example exhaust gases) when the heat exchanger is connected by the inlet opening thereof to their source.

[0015] In order to prevent the formation of a relatively cold plug of solidified poly meric feedstock in the pre-processing reactor, the shaft of the screw conveyor can be provided with a heating system, In particular, the heating system may comprise an electric resistance heating body. The heating of the inner space of the hollow shaft using hot gas (for example exhaust gases) or hot liquid may also be considered. The development has revealed that the existing approaches to solving this problem, which consist in locally increasing the temperature of the tube of the screw conveyor, do not yield satisfactory results. If the polymeric mixture were to solidify in the screw conveyor, the processing and movement thereof within the pre-processing reactor would be essentially impossible. The screw conveyor must be disassembled and cleaned.

[0016] In a preferred embodiment, the pitch of the screw of the screw conveyor in at least the last 1 / 5 of the effective length of the screw conveyor may be smaller (finer) than in the first 1 / 5 of the effective length of the screw conveyor. Further, the distance between the inner surface of the tube of the screw convey or and the surface of the shaft of the screw conveyor in at least the last 1 / 5 of the effective length of the screw conveyor may be smaller than in the first 1 / 5 of the effective length of the screw conveyor. This can be achieved by increasing the diameter of the shaft of the screw conveyor and / or reducing the inner diameter of the tube of the screw conveyor.

[0017] The choice of this screw convey or arrangement depends on the type of processed polymeric feedstock. However, the purpose is for the polymeric feedstock to become compacted with the increasing temperature while progressing through, the pre-processing reactor and to fill the entire inner cross-section of the tube of the screw conveyor. Thereby, a plug is gradually formed in the pre-processing reactor, which aids the movement of the components released in the heating process from the polymeric feedstock towards the outlet from the pre-processing reactor. Thus, the reduction of the inner cross-section and pitch of the screw of the screw conveyor regulate the density of the polymeric feedstock, or the degree of filling of the inner space of the pre-processing reactor with the polymeric feedstock, and the speed of its movement through the pre-processing reactor. It is desirable for the change of the pitch of the screw and the distance between the inner surface of the tube of the screw conveyor and the shaft of the screw conveyor to be smooth, gradual .

[0018] This definition of the screw arrangement and / or the diameter of the shaft of the screw conveyor means that the given element is located at least within the specified section of the effective length. It can of course be used in a longer section, for example in the last 1 / 3 or 1 / 2 of the effective length. It is essential that the above technical effect is achieved, at the end of the effective length of the screw conveyor - compaction of the polymeric feedstock at the outlet from the pre-processing reactor, which is characterized by filling the entire cross-section of the tube before reaching the end of the effective length of the screw conveyor.

[0019] The pre-processing reactor is used for heating of the polymeric feedstock and mixing it with catalysts (neutralizers) into a homogeneous mix. It also ensures the exclusion of gaseous halogens and their discharge (extraction) into the neutralization device. The longitudinal axis of the pre-processing reactor (i.e., the axis of rotation of the screw conveyor) may be horizontal, inclined, or vertical. The choice of the orientation of the pre-processing reactor is determined by the type of the processed polymeric feedstock. For mixed municipal waste, it is preferable if the orientation of the longitudinal axis of the pre-processing reactor is vertical. For tires and sludges, it is preferably inclined, and for plastics, it can be mainly horizontal.

[0020] In particular, the described pre-processing reactor can be utilized within the structure of the recycled polymeric feedstock processing device, where the described pre-processing reactor is integrated, before the main reactor with the heating system in which the actual depolymerization of the polymers takes place. Such a device is a related invention described below.

[0021] The device comprises a container for the processed polymeric feedstock, provided with a dosing device. The container is connected to an inlet hermetic closure via a feedstock line. The inlet hermetic closure is provided with an inert gas supply. The inlet hermetic closure can be a hermetic chamber filled with an inert gas with a closable inlet and outlet opening. The purpose of the inlet hermetic closure is to prevent atmospheric air from entering the downstream parts of the device and also the gaseous substances from exiting the device back into the container and possibly into the ambient air,

[0022] The polymeric feedstock with a defined maximum fraction is introduced into the container. The polymeric feedstock can be supplemented with a catalyst (neutralizer). The purpose of the catalyst (neutralizer), if used, is to improve both the physical and chemical processes and to isolate the halogens typically found in the polymeric feedstock. The choice of possible use and the amount of catalyst (neutralizer) depends on the composition and degree of contamination of the inlet polymeric feedstock. The dosing device may be, for example, a press or other solid material conveyor or may be part of gravitational transport of the polymeric feedstock (mass or volume dosing device). The pre-processing reactor described above is connected to the outlet from the inlet hermetic closure by the feedstock line. A multi -jacketed main reactor with a heating system for the depolymerization of polymers is connected to the outlet from this pre-processing reactor. The polymeric feedstock from the pre-processing reactor proceeds to the main reactor by gravity or under pressure, depending on the type of the polymeric feedstock. In this configuration, the plug of preheated and prepared polymeric feedstock in the pre-processing reactor also prevents th e passage of hot gases from the main reactor to the pre-processing reactor.

[0023] The main reactor comprises at least an inner chamber and an outer chamber. The inner chamber is connected to the pre-processing reactor by the feedstock line. The outer chamber covers at least a part of the surface of the jacket of the inner chamber. The outer chamber is provided with or connected to a heat source for heating the inner chamber. The process of cyclic (repeated.) thermal-catalytic depolymerization and reforming of the polymeric feedstock takes place in the main reactor at a defined high temperature. The reforming of the polymeric feedstock refers to a process where the desired single molecules or new short molecular chains are formed from the depolymerized (broken) molecules. In addition to waste solid residues, a hot steam-and-gas mixture is formed by the decomposition of the polymeric feedstock. The steam-and-gas mixture usually includes hydrogen, carbon monoxide, etc. In addition, it includes particularly a wide spectrum of hydrocarbons: from those with the lightest molecular weight (gases CH4, C2H6.. .) to heavy condensable hydrocarbon vapors, which then form the liquid fraction of the finished product.

[0024] In a preferred embodiment, the heating system of the main reactor may comprise a combustion chamber located in the bottom part thereof. The inner space of the combustion chamber is connected to the inner space of the outer chamber of the main reactor. The exhaust gases from the combustion chamber enter the interspace between the wall of the inner and the outer chamber of the main reactor through a deflector that prevents direct contact of the flame with the jacket of the inner chamber. The outer chamber i s thus de facto a heat exchanger with inner volume separated from the inner volume of the inner chamber. The exhaust gases from said interspace transfer heat to the inner chamber. The exhaust gases then from this interspace preferably continue via an exhaust gas path to the heat exchanger of the pre-processing reactor. The heating of the pre-processing reactor can thus be at least partially provided by the residual heat from heating the main reactor.

[0025] The combustion chamber is provided, with at least one fuel burner connected to an external fuel line, The gas from the external fuel line is usually the primary fuel source, At the same time, a gas line with a gas container leads into the combustion chamber, which originates from a separation tank. Preferably, the gaseous fraction from the processed polymeric feedstock may be post-combusted, separated from the liquid fraction in the separation tank. It can then serve as a secondary fuel source, which is both ecological and economic (disposal of gaseous products is ensured and their leakage into the air is prevented, in addition, they are utilized for heating systems).

[0026] The inner chamber of the main reactor is in the bottom part provided with a. solid residue conveyor. The solid residue conveyor carries solid residues from the processing of the polymeric feedstock out of the main reactor and leads into a solid residue cooling device. The solid residue cooling device is provided at the outlet thereof with an outlet hermetic closure with inert gas supply. The outlet hermetic closure prevents atmospheric air from entering the downstream parts of the device and the gaseous substances from exiting the device into the ambient air.

[0027] The inner chamber of the main reactor is provided in the upper part thereof with a steam-and- gas mixture discharge, which is connected to a separator. The hot steam-and-gas mixture in the separator is partially condensed, mixed, and its molecularly heavier parts return upstream of the incoming steam-and-gas mixture and eventually to the main reactor. During the counter-flow movement of the interacting phases of the partially condensed steam-and-gas mixture, a chemical mass transfer occurs, thereby improving the quality of the resulting product. In the main reactor, any returned condensate is reheated and repeatedly subjected to the thermal- catalytic depolymerization process together with depolymerization of the newly processed polymeric feedstock supplied from the pre-processing reactor.

[0028] The separator may preferably be an essentially vertical body (the longest axis of the body is essentially vertical). The body may preferably be a cylinder. The steam-and-gas mixture line from the main reactor enters the body of the separator from below. In the separator, there is a set of partial baffles where the rising h ot steam-and-gas mixture encounters and is mixed with the condensate flowing towards the main reactor as it progresses upwards. In this process, there is a bidirectional chemical mass transfer between the gaseous and liquid fractions.

[0029] After the partially transformed steam-and-gas mixture exits the upper part of the separator, which is enriched by the chemical mass transfer, the mixture progresses by the overpressure and by gravity from above to the condensation block. At the inlet to the condensation block, the partially transformed steam-and-gas mixture already comprises the primary condensing component. The condensation block may preferably be an essentially vertical body (the longest axis of the body is essentially vertical). The body may preferably be a cylinder. The condensation block also comprises a set of partial baffles, which the mixture impinges on, is mixed with, and is further condensed. In doing so, it progresses by the overpressure and by gravity to the separation tank, which is downstream of the condensation block. A siphon passage is located between the condensation block and the separation tank. It provides the necessary overpressure in the preceding parts of the device; in addition, by bubbling the gaseous fraction through the liquid fraction, further desirable chemical reactions and / or purification of the gaseous fraction can take place. The separation tank is used to separate the gaseous and liquid fractions exiting the condensation block.

[0030] Together wdth the separator, condensation block, and separation tank, the inner chamber of the main reactor forms a so-called cyclic gravitational molecular sieve (sometimes also called a ''rectification block”). The cyclic gravitational molecular sieve ensures the output of the finished product wdth the desired quality (partially condensed steam-and-gas mixture with hydrocarbons of a certain maximum molecular weight, the composition of which is adjustable by the device parameters such as temperature and pressure). It can be said that the cyclic gravitational molecular sieve is a device for controlling the molecular weight of the partially condensed steam-and-gas mixture at the outlet from the separation tank at a given temperature.

[0031] The separation tank is connected to a liquid fraction filtration. The liquid fraction filtration is used to remove unwanted solid impurities. Preferably, it is centrifugal filtration. The liquid fraction filtration is connected to the liquid fraction storage tank. An embodiment where the liquid fraction filtration is in a single block together with the storage tank may also be considered. The liquid fraction storage tank can be provided wdth a liquid fraction discharge for its further processing.

[0032] Description of Drawings

[0033] An exemplary embodiment of the proposed solution is described with reference to the drawings, which show in fig. 1 - a schematic view of the device: fig. 2 - a schematic vertical longitudinal section of the pre-processing reactor. Exemplary Embodiment of the Inventi on

[0034] The pre-processing reactor 3 intended for the recycled polymeric feedstock processing device comprises a screw conveyor 31 in a hermetically closed tube 32. The tube 32 is provided with a halogen discharge pipeline 35 into a neutralization device in the last 1 / 3 of the effective length x of the screw conveyor 31. The effective length x of the length of the screw conveyor 31 is defined from the front edge of the inlet opening of the polymeric feedstock (and completely overlapping its cross-section) to the front edge of the outlet opening of the polymeric feedstock (and not extending into its cross-section).

[0035] The pitch of the screw of the screw conveyor 31 in the last 1 / 5 of the effective length x of the screw conveyor 31 is smaller (finer) than in the first 1 / 5 of the effective length x of the screw' conveyor 31. At the same time, the distance between the inner surface of the tube 32 of the screw' conveyor 31 and the surface of the shaft 37 of the screw' conveyor 31 in the last 1 / 5 of the effective length x of the screw conveyor 31 is smaller than in the first 1 / 5 of the effective length x of the screw' conveyor 31. This is achieved by increasing the diameter of the shaft 37 of the screw conveyor 31 .

[0036] The pre-processing reactor 3 is provided with a heating system for the mechanical-thermal- chemical preparation of the polymeric feedstock. The heating system of the pre-processing reactor 3 comprises a set of electric heating members 34 connected to a temperature sensor 33 in the last 1 / 5 of the effective length x of the screw conveyor 31. The heating members 34 are arranged, from the perspective of the movement of the polymeric feedstock, in front of the temperature sensor 33. The temperature sensor 33 is arranged on the closer (front) edge of the outlet opening of the pre-processing reactor 3, i.e,, at the end of the effective length x of the screw conveyor 31. This ensures that the prepared polymeric feedstock reaches the defined chemical-physical state at the outlet from the pre-processing reactor 3 at the moment it enters its outlet opening.

[0037] The heating system of the pre-processing reactor 3 is further included in the shaft 37 of the screw conveyor 3.1., where an electric heating body is arranged. The heating system of the pre- processing reactor 3 further comprises a heat exchanger 36. The heat exchanger 36 is arranged around the tube 32 of the screw con veyor 31. In this exemplary embodimen t, the heat exchanger 36 extends approximately between 2 / 5 to 4 / 5 of the effective length x of the screw conveyor 31. The heat exchanger 36 is provided with forced extraction. An exemplary recycled polymeric feedstock processing device comprises the pre-processing reactor 3 described above. The device further comprises a container 1 for the processed polymeric feedstock. The container 1 is provided with a dosing device, which is connected to an inlet hermetic closure 2 with an inert gas supply by a feedstock line. The outlet from the inlet hermetic closure 2 is connected to the pre-processing reactor 3 by a feedstock line. The outlet opening of the pre-processing reactor 3 is introduced into a main reactor 4 by a polymeric feedstock line. The main reactor 4 is multi-jacketed and comprises an inner chamber 41 and an outer chamber 42. The inner chamber 41 is connected by the feedstock line to the outlet opening of the pre- processing reactor 3. The outer chamber 42 completely covers the surface of the jacket of the inner chamber 41 (the inner chamber 41 is completely enclosed in the outer chamber 42).

[0038] The heating system of the main reactor 4, the purpose of which is to provide depolymerization of polymers, comprises a combustion chamber 17. The combustion chamber 17 is provided with a fuel burner that is connected to an external fuel line 13. At the same time, a gas line 15 with a gas container 16, which originates from a separation tank 9, leads into the combustion chamber 17. The inner space of the combustion chamber 17 is connected to the inner space of the outer chamber 42 of the main reactor 4. The outer chamber 42 of the main reactor 4 is connected via an exhaust gas path 11 to the inlet opening of the heat exchanger 36 of the pre- processing reactor 3.

[0039] In its bottom part, the inner chamber 41 of the main reactor 4 is provided with a solid residue conveyor 5 leading into a solid, residue cooling device 6. The cooling device 6 is provided at the outlet thereof with an outlet hermetic closure 7 provided with an inert gas supply, The solid residues can then be collected in an external solid residue container 14.

[0040] Further, the inner chamber 41 of the main reactor 4 is provided in its upper part with a steam- and-gas mixture discharge 18, which is connected to a separator 8. The upper part of the separator 8 is connected to the upper part of a condensation block 19 by a sloped line. The bottom part of the condensation block 19 is provided with a siphon passage to the separation tank 9. The inner chamber 41 of the main reactor 4, the separator 8, the condensation block 19, and the separation tank 9 together form a cyclic gravitational molecular sieve. The separation tank 9 is connected to a centrifugal liquid fraction filtration 10. The liquid fraction filtration 10 is connected to a storage tank 12. List of Reference Signs 1 container for the processed polymeric feedstock with a dosing device

[0041] 2 inlet hermetic closure

[0042] 3 pre-processing reactor

[0043] 4 - main reactor

[0044] 5 solid residue conveyor from the main reactor

[0045] 6 solid residue cooling device

[0046] 7 outlet hermetic closure

[0047] 8 separator

[0048] 9 - separation tank

[0049] 10 - liquid fraction filtration

[0050] 11 - exhaust gas path

[0051] 12 storage tank

[0052] 13 external fuel line

[0053] 14 solid residue container

[0054] 15 gas line

[0055] 16 gas container

[0056] 17 combustion chamber

[0057] 18 steam-and-gas mixture discharge

[0058] 19 condensation block

[0059] 31 - screw conveyor of the pre-processing reactor

[0060] 32 - tube of the screw conveyor

[0061] 33 temperature sensor

[0062] 34 electric heating member

[0063] 35 halogen discharge pipeline

[0064] 36 heat exchanger

[0065] 37 shaft of the screw conveyor

[0066] 41 inner chamber of the main reactor

[0067] 42 outer chamber of the main reactor x effective length of the screw conveyor

Claims

Claims1. A pre-processing reactor for a recycled poly meri c feedstock processing device, characterized in that it comprises a screw' conveyor (31) in a closed, tube (32) provided, with an inlet opening and an outlet opening of the processed polymeric feedstock, where the screw conveyor (31) has an effective length (x) comprising the length of the screw conveyor (31) from the front edge of the inlet opening of the polymeric feedstock and completely overlapping the cross-section thereof to the front edge of the outlet opening of the polymeric feedstock and. not extending into its cross-section, wherein the tube (32) is provided with a halogen discharge pipeline (35) in the last 1 / 3 of the effective length (x) of the screw conveyor (31) and the pre-processing reactor (3) is provided with a heating system for the mechanical-thermal- chemical preparation of the polymeric feedstock that comprises in the last 1 / 5 of the effective length (x) of the screw conveyor (31) at least one electric heating member (34) connected to at least one temperature sensor (33) to provide a. defined chemical-physical state of the prepared polymeric feedstock in the outlet opening of the pre-processing reactor (3).

2. The pre-processing reactor according to claim 1, characterized in that the heating system of the pre-processing reactor (3) further comprises an air heat exchanger (36) provided with an inlet and outlet opening, wherein at least a part of the outer surface of the tube (32) of the screw conveyor (31) extends into the inner space of the heat exchanger (36) for the thermal energytransfer from the inner space of the heat exchanger (36) into the tube (32) of the screw conveyor (31).

3. The pre-processing reactor according to any one of claims 1 or 2, characterized in that the shaft (37) of the screw conveyor (31) is provided, with a heating system.

4. The pre-processing reactor according to any one of the preceding claims 1 to 3, characterized in that the pitch of the screw' of the screw conveyor (31) in at least the last 1 / 5 of the effective length (x) of the screw conveyor (31) is smaller than in the first 1 / 5 of the effective length (x) of the screw conveyor (31).

5. The pre-processing reactor according to any one of the preceding claims 1 to 4, characterized in that the distance between the inner surface of the tube (32) of the screw conveyor and the surface of the shaft (37) of the screw conveyor (31) in at least the last 1 / 5 of the effective length (x) of the screw conveyor (31) is smaller than in the first 1 / 5 of the effective length (x) of the screw conveyor (31).

6. A recycled polymeric feedstock processing device comprising the pre-processing reactor according to any one of the preceding claims 1 to 5, characterized in that it comprises a container (1) for the processed polymeric feedstock provided with a dosing device, which is connected to an inlet hermetic closure (2) provided with an inert gas supply via a feedstock line, the outlet of the inlet hermetic closure (2) is connected to the inlet opening of the pre-processing reactor (3) and the outlet opening of the pre-processing reactor (3) is connected to the inlet opening of a multi-jacketed main reactor (4) with a heating system for the depolymerization of polymers, where the main reactor (4) comprises at least an inner chamber (41) provided with an inlet and an outlet opening and an outer chamber (42) that at least partially covers the outer surface of the jacket of the inner chamber (41), wherein the outlet opening in the bottom part, of the inner chamber (41) of the main reactor (4) is provided with a solid residue conveyor (5) leading into a solid residue cooling device (6), which is provided at its outlet with an outlet hermetic closure (7) provided with an inert gas supply, and further, the inner chamber (41) of the main reactor (4) is in the upper part thereof provided with a steam-and-gas mixture discharge (18) which is connected to a separator (8) with a. downstream condensation block (19), and there is a separation tank (9) downstream of the condensation block (19), connected to a liquid fraction filtration (10), which is connected to or provided with a storage tank (12).

7. The device according to claim 6, characterized in that the heating system of the main reactor (4) comprises a combustion chamber (17) that is connected to the separation tank (9) by a gas line (15) with a gas container (16),wherein the inner space of the combustion chamber (17) is connected to the inner space of the outer chamber (42) of the main reactor (4) and the combustion chamber (17) is provided with at least one fuel burner that is connected to an external fuel line (13).

8. The device according to any one of claims 6 or 7, characterized in that the inlet opening of the heat exchanger (36) of the heating system of the pre-processing reactor (3) is connected to the outer chamber (42) of the main reactor (4) by an exhaust gas path (11).

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