Method for a real-time analysis and inspection of the release of volatile compounds in production, processing, or recycling methods, in particular during the extrusion process

Abstract

The invention relates to a method for the real-time analysis or the near-real-time analysis and optionally the real-time inspection or near-real-time inspection and regulation of the release of volatile compounds in methods for producing, processing, or recycling materials, said materials being heated or melted and optionally additionally degassed for processing purposes. The method has the steps of collecting a sample; guiding the sample which has the volatile compounds to an analysis device for a real-time analysis or near-real-time analysis of the volatile compounds, including a measurement and analysis of the volatile compounds; and if necessary controlling and regulating parameters of the production, processing, or recycling methods in order to maximize the release and discharge of said volatile compounds and thus reduce the remaining volatile substances in the processed material. Furthermore, a device is provided comprising a process unit, in particular an extruder, for processing the material, said process unit having a device for collecting a sample of the volatile compounds during processing and at least one analysis device for a real-time analysis or a near-real-time analysis of the volatile compounds, and comprising a controller for processing the material, said controller being designed to control, optimize, and regulate parameters of the processing of the materials and the cleaning performance on the basis of data obtained during the real-time analysis or near-real-time analysis of volatile compounds. The invention also allows a continuous process inspection for quality control purposes and a rejection of the generated materials or recycled products in the event of undesired input streams or an excessively high degree of contamination thereof.

Description

[0001] Method for real-time analysis and control of the release of volatile compounds in the manufacturing, processing or recycling process, in particular during extrusion

[0002] The present invention relates to a method for real-time or near-real-time analysis and, if necessary, real-time or near-real-time control of the release of volatile compounds in a manufacturing, processing, or recycling process for materials, wherein the materials are heated or melted for processing and, if necessary, additionally degassed. The method includes the steps of taking a sample, passing the sample containing the volatile compounds to an analysis device for real-time or near-real-time analysis of the volatile compounds, with measurement and analysis of the volatile compounds, and, if necessary, controlling and regulating parameters of the manufacturing, processing, or recycling process to maximize the release and removal of these volatile compounds and thus to reduce the remaining volatile substances in the processed material or even increase them by deliberately adding them.Furthermore, a device is provided with a process unit, in particular an extruder, for material processing, comprising at least one device for sampling volatile compounds during processing, as well as at least one analysis device for real-time or near-real-time analysis of the volatile compounds, and a control device for the material processing configured to control, optimize, and regulate material processing parameters based on data obtained during the real-time or near-real-time analysis of volatile compounds. Furthermore, the present invention enables continuous process monitoring for quality control and near-real-time rejection of such produced materials or recyclates with undesirable or excessive contamination of the input streams. State of the art.

[0003] During the manufacturing, processing, or recycling of materials, particularly when these materials are heated or melted to improve material processing, volatile substances or volatile compounds are released. These volatile compounds released during processing can be of a wide variety. They can be, for example, harmful to health or the environment, as well as odorous substances, residues from material production (e.g., residual monomers, catalyst residues, residual solvents, etc.), substances in recyclates (decomposition products, printing ink residues, etc.), substances absorbed during the use phase (flavors, oils, fats, fuels), or similar.

[0004] Volatile substances are often removed during processing using negative pressure, e.g., vacuum degassing.

[0005] These undesirable odorous substances and volatile compounds must be removed as completely as possible during the processing so that they are not released from the manufactured product itself at a later stage.

[0006] Such compounds are particularly prone to outgassing during extrusion. Depending on the materials being processed, these can be contaminated to varying degrees with odorous substances and volatile compounds, which can be released during the process and even after production. Accordingly, necessary quality control of these compounds is essential, both during the manufacturing process and in relation to the final product.

[0007] However, the existing methods, particularly those for quality control of finished products, suffer from the fact that they do not provide information about possible contamination of the input stream during the actual manufacturing process. Accordingly, the manufacturing process cannot be monitored or influenced in a timely manner.

[0008] Various approaches to solving this problem already exist. One problem, however, is that the analysis of the compounds' outgassing emissions is usually performed using offline methods, meaning there is no timely analysis of emissions during the manufacturing process. Common offline methods include the so-called triangle test according to DIN EN ISO 4120, the profile test according to DIN EN ISO 12299, rapid sensory methods VDA 270 or VDA 277 and 278, and ISO 16000-28.

[0009] DE 10 2007 061 666 B4 describes a method for determining material properties. The method involves determining the material properties of a workpiece during production, e.g., by extrusion. In particular, an analysis of the gases diffused into the ambient air during the manufacture of a workpiece is described. In the case of a continuously produced extruded profile, a material-removing seaming or workpiece separation takes place after leaving a production line. The removed material from the extruded profile is essentially continuously removed and separated in a material stream, and samples are taken for analysis so that the analysis result can be assigned to a specific workpiece. However, the method does not allow for online analysis during the manufacturing process, and in particular, it does not allow for subsequent control, optimization, or regulation of the process.

[0010] EP 2 760 618 B1 describes a method with a device for removing volatile components from polymer-containing media. EP 1 713 832 B1 discloses a device with a method for measuring a polymerization reaction by taking and analyzing a sample. EP 1 119 800 B1 describes a system for online interference of physical and chemical properties and systems for online control of plants based on model-predictive control algorithms.

[0011] Patel, SH et al., 2001, 20(1), 22 to 41, provides an overview of polymer processing, particularly the emission of volatile compounds and their detection. The methods used to analyze potentially volatile compounds, particularly offline, are described in general. Typically, corresponding analysis units are placed downstream of the extruder. DE 199 34 349 A1 describes analysis methods for the continuous, analytical monitoring of polymers during their production or processing. The extrudate is analyzed using a "gas dome" after leaving the extruder. DE 10 2010 042 958 A1 describes a system and method for the continuous production of preforms. Volatile compounds are determined after the extrudate leaves the melt generation section of the system, the extruder. The same also applies to the disclosure of US 2011 / 0154883 A1.DE 10 2007 029 010 A1 generally describes a process for compounding polymers. It describes the use of entraining agents to reduce the content of residual solvents, monomers, or oligomers.

[0012] However, all of the processes suffer from the fact that they are either carried out as offline methods or that the analysis of the volatile compounds and produced extrudates takes place after leaving the extruder and, in particular in the case of extrusion processes, only the analysis of the produced product is carried out afterwards, but not a real-time or online analysis and the associated control and regulation of the process towards optimal operating points at which a maximum of volatile compounds is removed even with variable input flows.

[0013] This means that environmentally harmful and health-damaging substances, including odorous substances, can only be analyzed and analyzed at a later point in time using existing methods, meaning that their emissions cannot be directly influenced during the manufacturing process. These unpleasant odors represent a major disadvantage, particularly in modern processes that use recyclates, such as plastic recyclates or composite recyclates, and thus limit their use in various industries. As a result, the resulting extrudates or granules, or the manufactured products, such as packaging, are stored temporarily and only released for further use after these products have been analyzed for potentially harmful substances. This results in high inventory levels and the potential destruction of large quantities of manufactured products.In addition, these individual analyses as samples cannot reflect possible batch-related changes throughout the production process, e.g. due to variable input flows.

[0014] Methods for reducing outgassing substances, such as volatile compounds, are known in the art. For example, to reduce the odor of plastics, entraining agents, e.g., in the form of granules or in liquid form, e.g., water or carbon dioxide, are introduced during the processing. These entraining agents can be used to remove the substances from the process, e.g., using appropriate vacuum devices. However, as described above, their control, in particular the verification of their effectiveness, is only achieved through downstream offline processes, which, moreover, are associated with a significant amount of time. Other methods for determining the chemical composition during the extrusion process are limited to analyzing the melt using near-infrared spectroscopy.

[0015] There is therefore a need to provide methods that allow real-time or online analysis of undesirable substances in the material being processed and the resulting product during the processing process, in order to control and optimize process parameters accordingly. In particular, this allows optimal process windows or specific operating points to be found and adjusted, where a maximum of volatile compounds are removed, even with variable input streams, so that a minimum of them remains in the final product.

[0016] Brief description of the invention

[0017] The present invention relates to suitable methods for real-time analysis or near-real-time analysis and, where appropriate, real-time control or near-real-time control of the release of volatile compounds in a manufacturing, processing, or recycling process of materials, wherein these materials are heated and / or melted and / or degassed for processing, comprising the steps:

[0018] - sampling of volatile compounds at at least one position of the process unit of the process;

[0019] - Directing these volatile compounds to an analysis device for real-time or near-real-time analysis of the volatile compounds;

[0020] - Measurement and analysis of volatile compounds;

[0021] - if necessary, controlling process parameters to maximize the removal of these volatile compounds or to minimize / maximize the remaining / added volatile compounds in the resulting product of the process,

[0022] - Sampling of volatile compounds in a degassing zone of the process unit of these manufacturing, processing or recycling processes.

[0023] A further step may also be the rejection of the product. If the input stream contains too many critical substances, these will be immediately and directly detected in the inline process according to the invention. The product can thus be immediately sorted out as part of the online quality control. In contrast, the downstream offline analysis of the state of the art only allows for random sampling, so that the detection of critical substances is subject to the sampling statistics and may therefore be lost.

[0024] The method according to the invention is particularly suitable for processing materials in the form of an extrusion of these, e.g., plastic-containing materials, in particular recyclates.

[0025] The corresponding analysis system for the volatile compounds, hereinafter also referred to as a gas analysis system, comprises a device for sampling the volatile compounds at at least one position in the processing process. It also comprises an analysis device, such as a gas chromatograph, wherein the information obtained by the gas chromatograph is used, possibly with the aid of a control device, to control parameters and regulations of the processing process.

[0026] In a further aspect, the present invention is directed to a device for material processing with a process unit, in particular an extruder. This device comprises, in addition to the actual processing space, e.g. in the case of an extruder, the corresponding extrusion chamber (process part), at least one device for sampling volatile compounds during the manufacturing, processing, or recycling process, at least one analysis device for real-time or near-real-time analysis of the volatile compounds, wherein this analysis device is conductively connected to a device for sampling; a control device of the processing process configured to control and regulate parameters of the processing process on the basis of data obtained by the real-time or near-real-time analysis of volatile compounds.

[0027] That is, in one embodiment, the device according to the invention comprises an extruder with a gas analysis system according to the invention, as described, wherein the device for sampling volatile compounds is arranged upstream of the outlet of the extruder, ie within the compounding or recycling process.

[0028] Description of the characters

[0029] Figure 1 - a schematic representation of the device according to a

[0030] Embodiment.

[0031] Figure 2 - schematic flow of the process using a

[0032] Flow diagram. Detailed description of the invention

[0033] The present invention relates in a first aspect to a method for real-time analysis or near-real-time analysis and optionally near-real-time control of the release of volatile compounds in a manufacturing, processing or recycling process of materials, wherein these materials are heated or melted for processing and optionally additionally degassed, comprising the steps:

[0034] Sampling of volatile compounds at at least one position of the process unit of the process;

[0035] Directing these volatile compounds to an analysis device for real-time or near-real-time analysis of the volatile compounds;

[0036] Measurement and analysis of volatile compounds; if necessary, control and regulation of process parameters to remove these volatile compounds or to minimize the remaining volatile compounds in the resulting product of the process, wherein the sampling of volatile compounds takes place in a degassing zone of the process unit of this manufacturing, processing, or recycling process.

[0037] In one aspect of the invention, an increase in volatile compounds is further achieved by introducing these compounds, e.g., deodorization by introducing fragrances or odor inhibitors, etc.

[0038] In this case, “real-time analysis” means that the sample taken is fed directly to the analysis device via a conductive connection, where it is immediately measured and analyzed.

[0039] The term “near real-time” means that there is a period of time between sample collection and receipt of the analysis of a maximum of 20 minutes, such as a maximum of 10 minutes, preferably also less than 8 minutes, 6 minutes, 5 minutes or less.

[0040] The term "volatile compounds" refers to substances and compounds that are volatile at room temperature or upon heating or melting up to the processing temperature due to their low vapor pressure or low boiling point, i.e., they degas from the material. These are usually small molecules, e.g., short-chain organic substances. These volatile compounds escape in fluid form, i.e., as eluate, in liquid or gaseous form. Volatile compounds include, in particular, highly volatile organic compounds that degas from the material due to their low boiling points and lower vapor pressure at lower temperatures.

[0041] The term ‘measurement and analysis’, and in particular the term ‘analysis’, covers different forms of information or data obtained.

[0042] The term “melting” or “melted” refers to a material processing in which the viscosity of the material is reduced by the addition of energy in the form of heat or radiation, making the material more flowable.

[0043] On the one hand, the analysis can be a determination of the substances themselves, i.e., a determination of the released volatile compounds as such. However, the analysis can also be a semi-quantitative or quantitative analysis of the specific released substances. In this case, the analysis can include a complete determination of the released volatile compounds. In an alternative embodiment, the analysis can include a determination of model substances that represent a group of substances.

[0044] The method according to the invention allows, on the basis of the gas analysis system used, a rapid determination of the volatile compounds in order to ensure the reduction of the release of these volatile compounds, in particular at a later time, or to enable an improvement in the removal of these volatile compounds, including odor-active substances, during the manufacturing, processing, or recycling process.

[0045] This can be done and controlled with the help of entraining agents or extraction agents, as explained in more detail below.

[0046] The method according to the invention is characterized in that, due to the possibility of real-time analysis or near-real-time analysis, the substances that negatively influence the processing and use of the manufactured products, such as unpleasant odor, etc., can be reduced.

[0047] In one embodiment, the manufacturing, processing, or recycling process for materials according to the invention is an extrusion process. The term "extrusion process" refers to all types of extrusion processes, including compounding, recycling, or the production of profiles, films, and fibers by extrusion. In one embodiment, the manufacturing, processing, or recycling process is thus compounding, which can be carried out using an extruder but also using other known processes. Compounding typically means the targeted production of specific material compositions by admixing additives with appropriate processing of the raw material to produce the desired product from the corresponding starting materials.

[0048] In one embodiment, the process is one in which at least one sample is taken for analysis of the volatile compounds upstream of the extruder die. In contrast to the prior art, in which the analysis of volatile compounds and harmful compounds in the extrudate is performed downstream of the extruder, i.e., offline, so to speak, early online or inline analysis allows for rapid control and regulation of both the respective feed materials and the entraining and extraction agents used.

[0049] The materials usable according to the invention include, in particular, plastics. In one embodiment, the materials to be processed are plastics or plastic-containing compositions, such as composites. In one embodiment, these materials are recyclates that are appropriately processed and transformed into new products.

[0050] Extrusion typically produces granules, which are then further processed in appropriate processing machines, such as injection molding machines, etc. Other products of extrusion include profiles, fibers, foams, or films. In one embodiment, the method according to the invention is used in a processing process for plastic-containing materials in the form of an extrusion to obtain processed granules from recyclates as intermediate products.

[0051] In one embodiment, the volatile compounds are sampled in a vent zone of this processing method. For example, extruders have at least one vent zone in which volatile compounds are removed from the process. In one embodiment, the sample is taken in the last vent zone of the extruder before the product, typically extrudates or granules, exits.

[0052] Extrusion equipment often features degassing zones for removing volatile compounds. This degassing is typically achieved by applying negative pressure, e.g., through suitable vacuum degassing or atmospheric degassing.

[0053] Corresponding devices and methods are known to those skilled in the art. In one embodiment, the volatile compounds are sampled for analysis during degassing of the materials being processed, e.g., from the extruder.

[0054] As mentioned, extruders usually contain several degassing zones to remove volatile components from the molten material. Degassing is ensured and controlled by a vacuum pump.

[0055] Degassing points can be used simultaneously to feed in entraining agents or extraction agents, although these terms overlap. The use of entraining agents to remove these volatile components from the melt is well known. Common entraining agents include N2, CO2, or even (moist) air. These absorb the outgassing substances and transport them in the entraining agent stream to the degassing or outlet opening. Supercritical CO2 (pressure > 73.8 bar and temperature > 31.1 °C) or solvents can also be used as extraction agents. Since these extraction agents can also enter the vapor phase and "entrain" the dissolved substances, the terms and processes of entraining agent-assisted and extractive extrusion are used synonymously below.

[0056] In one embodiment of the present invention, the method involves removing the volatile compounds directly or as contained in the entraining or extraction agent and passing these volatile compounds to the analysis device under negative pressure, e.g., using a vacuum. In one embodiment, the analysis device is a gas chromatograph with possible subsequent detection. In one embodiment, the sample is fed under vacuum to the gas chromatograph and, in this case, with a suitable detector, e.g., a flame ionization detector or a mass spectrometer.

[0057] In one embodiment, the method further comprises the control and regulation of parameters of the manufacturing, processing, or recycling process based on the volatile compounds determined in the analysis. This control and regulation according to the invention can include the supply of suitable entraining agents and / or extraction agents to reduce the volatile compounds in the process product or to increase the outgassing of the volatile compounds, including the odorous compounds, from the material during processing. The control and optimization allows the reduction of the content of volatile compounds in the material through the appropriate supply of entraining agents and / or extraction agents.Real-time or near-real-time analysis essentially closes a control loop, allowing the optimization of process parameters for maximum degassing and, at the same time, monitoring of volatile substances during the manufacturing, processing, or recycling process. The method according to the invention also allows for continuous monitoring of extrusion and recycling processes. Continuous monitoring of the composition of the degassing substances or those contained in the entraining or extraction agents allows for the detection of excessively contaminated input streams in the process, and the resulting materials / recyclates can be separated out. The introduced entraining and extraction agents can serve as carriers for the substances to be analyzed.

[0058] The entraining agents and / or extraction agents can be supplied through at least one of the degassing points of the process unit, in particular the extruder.

[0059] In order to control in particular the effectiveness of the extraction agents and entraining agents, it is advantageous to carry out the sampling for the real-time analysis according to the invention at least at the last degassing zone.

[0060] In a further embodiment, the entraining agents and / or extraction agents are introduced into the extruder via an opening in the extruder, e.g., with the aid of corresponding inlet devices, usually appropriately controlled and regulated inlet valves or injection valves for the entraining agent or extraction agent. Thus, the entraining agents or extraction agents can be introduced into the extruder via these corresponding inlets and removed again at a second opening. The entraining agents or extraction agents are introduced into the extruder system in such a way that they are located both in the melt (particularly in the case of extraction agents such as supercritical CO2) and around the melt (particularly in the case of an entraining agent such as air or N2) in the empty space of the extruder, i.e., they overlie the melt accordingly in the compounding process.In one embodiment, the flow direction of the respective extraction agents or entraining agents can be the same as the flow direction of the melt. Alternatively, the flow direction (cocurrent) can also be in the opposite direction to the melt flow direction (countercurrent). The flow direction of the entraining gas or extraction agent can depend on the position of the feed and extraction. In one embodiment, the method and the device according to the invention can be designed such that the entraining gas or extraction agent used is analyzed for volatile components after removal from the process. Extraction agents and / or entraining agents can also be fed into the system multiple times; identical or different entraining agents and / or extraction agents can be fed at the same or different positions.

[0061] In one embodiment, the method is one in which the process itself is adapted to the process task or the process length or process duration in the extruder is extended in order to reduce the amount of volatile compounds in the extruder, in particular of environmentally harmful or health-damaging compounds, and to obtain extrudates that can then be immediately further processed. According to the invention, it is also possible to use two or more successive extruders in order to, for example, use different entraining agents to remove the volatile compounds. In this case, for example, in a first section of an extended extruder or in a first extruder when several extruders are present, one type of entraining or extraction agent, e.g.A polar entraining agent, such as water, is used, while in the subsequent section or in the second or subsequent extruder, a non-polar entraining agent, such as supercritical CO2, etc., is used. Furthermore, the invention can be used to analyze the undesirable volatile substances present in the first step, while in the second step, these are then removed by a specialized entraining agent.

[0062] Suitable extraction and entraining agents include air, water, CO2, especially supercritical CO2, and N2. The extraction or entraining agents can also be provided with additives, such as surfactants, to improve the entraining or extraction properties. In one embodiment, the process according to the invention for removing the volatile compounds can thus be carried out in a cascading manner. "Cascading" here means that in the first step, the process parameters are non-specifically designed for maximum cleaning performance, while in the second step, individual substances, such as odorous or toxic substances, are targeted.

[0063] With the aid of the method and the device according to the invention, it is possible to intervene in the process directly and during the ongoing process with the aid of the extraction agents and / or entraining agents on the basis of the real-time analysis of the volatile compounds and accordingly to specifically optimize the removal of the volatile compounds or, conversely, to reduce the volatile compounds remaining in the product during the extrusion process and in the process product.

[0064] The method according to the invention allows real-time analysis of volatile compounds, in particular odor-active substances, during processing in order to effectively and quickly optimize, control and regulate process parameters.

[0065] The method according to the invention allows a reduction in the amount of work and time required and is particularly suitable for controlling and optimizing processes in the context of plastics recycling, but also in the processing and development of composite materials or filled plastics, such as WPC and other cellulose fiber reinforced composite materials.

[0066] Parameters that can be used for control according to the invention include, in addition to the use of entraining and extraction agents, parameters such as temperature, speed, pressures, fill level, residence times, and other process parameters of the manufacturing, processing, or recycling process itself, as well as the corresponding amounts and types of the aforementioned entraining and / or extraction agents added, as well as the possible compounding of other additives that limit the subsequent undesired release of volatile compounds from the process product. These also include compounds such as odor absorbers, etc.

[0067] The extraction and entraining agents can have or fulfill additional properties and functions. These include disinfection and sterilization during the processing process, as well as general cleaning or decolorization.

[0068] In a further aspect, the present invention is directed to a device for material processing with a process unit, in particular an extruder, comprising at least one device for sampling volatile compounds during processing; at least one analysis device for real-time or near-real-time analysis of the volatile compounds, wherein this analysis device is conductively connected to a device for sampling; a control device of the processing method, configured to control and regulate parameters of the processing method based on data obtained by the real-time analysis or near-real-time analysis of the entraining and extraction agents with the volatile compounds contained therein.

[0069] The material processing device according to the invention can, in particular, be an extruder, wherein this extruder has a corresponding gas analysis device with the sampling device and the analysis device with corresponding zone discharges. In addition to this gas analysis device, the invention also provides a control device for controlling and regulating the manufacturing, processing, or recycling process. This control unit allows the process parameters of the device, e.g., the extruder, to be optimized, controlled, and regulated. Furthermore, this control device enables the supply of entraining agents or extraction agents to correspondingly predetermined positions of the material processing device, such as the extruder.

[0070] In one embodiment of the device according to the invention, the device is one in which the process unit comprises at least one extruder and at least one device for sampling volatile compounds arranged upstream of the outlet nozzle of the extruder. In one embodiment, the device can have two or more extruders. These extruders have corresponding devices for sampling and, if appropriate, devices for introducing entraining agents and / or extraction agents into the process unit, in particular the extruder. In one embodiment, the device can have one or more feed points for the entraining agent and one or more removal points for the entraining agent loaded with the detected volatile substances. The devices for sampling volatile compounds are designed in such a way that they take place upstream of the outlet nozzle of the corresponding extruder.If multiple extruders are present, these and the associated extrusion or recycling process parameters can be controlled and regulated via one or more control and regulation units for maximum and specifically optimized purification of the extrudate. In one embodiment, the device according to the invention comprises at least one analysis device for real-time analysis of the volatile compounds, which includes a gas detection unit. The detection unit can be a flame ionization detector or a mass spectrometer.

[0071] The device for introducing entraining and / or extraction agents into the process unit, in particular the extruder, can be coupled, for example, to the degassing zone of the unit, such as the extruder. It is also possible for the extraction or entraining agent to be added at a different point in the process than the sampling device. In one embodiment, the sampling device is arranged at the last degassing zone of an extruder, and this sampling device is conductively connected to a gas chromatograph. Furthermore, at least one vacuum pump is provided for generating a negative pressure and sampling, conveying the sample to the analysis device, and optionally removing volatile compounds from the processing in the extruder.

[0072] The device according to the invention is in particular a device for extruding plastics and / or plastic and composite recyclates.

[0073] Accordingly, the starting materials are fed into the extruder in the form of flakes, granules, agglomerates, powder, flat semi-finished products, or smaller components in order to obtain corresponding granules from the input streams.

[0074] The invention is further explained with reference to the figures.

[0075] Figure 1 shows an embodiment of the device according to the invention with the sub-reference to which the method according to the invention is explained in more detail.

[0076] The starting materials are fed to the extruder 1 via inlet 6. Possible starting materials are plastics and / or plastic and composite recyclates that are to be recycled and processed into granules for further processing. Samples of volatile compounds, which are removed, for example, during degassing, can be fed to the gas chromatograph 3 via line 9 via the sampling device 2. This is done, for example, with the help of the vacuum pump 4a. The composition of the volatile compounds and, if applicable, their quantities can be analyzed in real time or near real time using this gas chromatograph and a corresponding detector. The evaporation pressure is used to remove the samples and / or a vacuum is applied. Vacuum pump 4b allows additional removal of the volatile compounds from the extruder via the degassing zones 5a to 5d.

[0077] Process parameters can be controlled via the control unit 10. For example, entraining agents and / or extraction agents can be fed into the system from the storage container 11 via the venting openings 5a to 5d or via special inserts or injection openings in the extruder housing.

[0078] These special inserts can be designed such that the corresponding entraining or extraction agent is introduced into the extruder either in the direction of melt flow or against the direction of melt flow. For example, the entraining agent can be fed in via opening 5a and removed via opening 5b. The same or a different entraining or extraction agent can be introduced into the system again via 5c and, if necessary, removed via 5d. This also makes it possible, depending on the analysis of the substances entrained in the first entraining or extraction agent, to add a second entraining or extraction agent that is particularly suitable for removing certain substances. Alternatively, the entraining or extraction agent can also be introduced via 5c and also removed via 5b.Accordingly, the flow directions in the extruder are shown with A, while arrows B and C indicate possible flow directions of the entraining agent and / or extraction agent. Furthermore, the withdrawn entraining agent and / or extraction agent can also be fed via the corresponding gas line to the chromatograph for further analysis, e.g., via line 9 shown as an example.

[0079] The openings, e.g. 5a, ..., can be designed both for introducing the entraining and / or extraction agents and for removing the volatile organic compounds.

[0080] The respective positions in the drawing are chosen only as examples and show a possible process setup. The positions for the supply and discharge of the extraction and entraining agents, as well as the analysis of the outgassing substances, preferably entrained in the extraction and entraining agents, can also be located at various other locations.

[0081] The produced granulate 8 leaves the extruder via the extrusion die 7. Due to the process according to the invention, these granules contain the lowest possible amounts of odorous substances and volatile compounds. If necessary, contaminated process products can be separated out here as part of quality control.

[0082] As shown, the sampling is carried out in such a way that the corresponding openings 5a, 5b and 5c are arranged in front of the extrusion nozzle 7.

[0083] Figure 2 shows a flow diagram of the schematic sequence of the process according to the invention.

[0084] In step 20, a sample of volatile compounds or of the entraining or extracting agents containing the volatile compounds is taken at at least one position of the manufacturing, processing, or recycling process and this sample is passed to an analysis device, 25.

[0085] In the analysis device, the sample is then measured and analyzed in the next step 30. The analysis can include an analysis of selected model substances, e.g., for quality control or compliance with limit values, or an analysis of all components of the sample. The analysis can be qualitative, semi-quantitative, or quantitative. The measured data is then sent, for example, to an evaluation unit 40, which accordingly allows or maximizes the amounts and / or presence of certain volatile organic compounds in order to minimize the remaining residue in the final product (process product). The information or data thus obtained is then transmitted to a control unit, which, if necessary, regulates parameters of the processing method 50.Such control steps may include adding entraining agents and / or extractants during the manufacturing, processing, or recycling process, or adjusting the feed position, quantity, type, or composition of the extractant, as well as its residence time, 60, e.g., via the corresponding degassing zones, in order to modify the processing, 70, in particular to remove odorous substances from the processing process and reduce volatile compounds in the process product. Furthermore, process parameters such as temperatures, pressures, residence times, speed, filling level, etc., can be optimized and controlled to produce a maximum-purity end product.

[0086] The invention has been explained in more detail with reference to the figures, without being limited thereto. Those skilled in the art will be familiar with corresponding embodiments of the methods and the individual devices of the apparatus for implementing the invention. This includes, in particular, all continuous processes involving an extruder or an extrusion process, such as recycling, compounding, profile extrusion, or film, fiber, and foam production. Furthermore, the invention can also be used in continuous or discontinuous processes that can be installed upstream or downstream of the extruder, such as material drying or post-crystallization.

[0087] List of reference symbols

[0088] 1 extruder

[0089] 2 Sampling device

[0090] 3 Gas chromatograph

[0091] 4a, 4b,... Vacuum pump

[0092] 5a, 5b, 5c,... - degassing zone

[0093] 6 Entrance

[0094] 7 Extrusion nozzle

[0095] 8 granules

[0096] 9 Management

[0097] 10 Control unit

[0098] 11 storage containers

[0099] 20 Sampling

[0100] 25 Conducting the rehearsal

[0101] 30 Analysis

[0102] 40 Evaluation

[0103] 50 Control

[0104] 60 Supply of entraining and / or extraction agents

[0105] 70 modified procedure

[0106] A Flow direction of the melt in the extruder

[0107] B Flow direction extractant / entrainer

[0108] C Flow direction of entrainer / extractant

Claims

Patent claims 1 . A method for real-time or near-real-time analysis and, where appropriate, real-time or near-real-time control of the release of volatile compounds in a manufacturing, processing or recycling process of materials, wherein these materials are heated or melted for processing and, where appropriate, additionally degassed, comprising the steps: - sampling of volatile compounds at at least one position of the process unit of the process; - Directing these volatile compounds to an analysis device for real-time or near-real-time analysis of the volatile compounds; - Measurement and analysis of volatile compounds; - if necessary, controlling and regulating process parameters to maximize the removal of these volatile compounds or to minimize the remaining volatile compounds in the processed product, wherein the sampling of volatile compounds takes place in a degassing zone of the process unit of this manufacturing, processing or recycling process.

2. The method according to claim 1, wherein the manufacturing, processing, or recycling process of materials is an extrusion process including compounding.

3. The method according to claim 1 or 2, wherein the volatile compounds are highly volatile compounds such as eluates.

4. The method according to any one of the preceding claims, wherein at least one sample is taken for analysis of the volatile compounds before the extrusion nozzle.

5. The method according to any one of the preceding claims, wherein the sampling of volatile compounds takes place in a venting zone of an extruder.

6. The method according to claim 1, wherein the at least one devolatilization zone is at least the last devolatilization zone of the extruder before the product exits.

7. The method according to any one of the preceding claims, wherein the material comprises plastics.

8. The method according to claim 1, wherein the material is recyclate, in particular plastic recyclate.

9. The method according to any one of the preceding claims, wherein the removal of the volatile compounds and the conduction of these volatile compounds takes place under the application of negative pressure.

10. The method according to any one of the preceding claims, wherein the sampling of the compounds for analysis occurs during degassing of the materials.

11. The method according to any one of the preceding claims, wherein the analysis device comprises gas chromatography with subsequent detection.

12. The method according to one of the preceding claims, wherein the control and regulation of parameters of the manufacturing, processing, or recycling process for reducing and optionally increasing the content of volatile compounds in the material comprises the supply of entraining agents, in particular air, steam, N2, or CO^.

13. The method according to any one of the preceding claims, wherein the control and regulation of parameters of the manufacturing, processing or recycling process for the maximum removal of these volatile compounds or for the minimization and optionally increase of the remaining or optionally added volatile compounds of these in the product obtained from the process, the supply of extraction agents, entraining agents and / or in particular supercritical CO2, water vapor or Odor absorbers. The process according to claim 11 or 12, wherein the entraining agents and / or extraction agents are supplied through degassing points or special inserts of the process unit, in particular the extruder. The process according to one of the preceding claims, wherein process products that do not meet the requirements regarding remaining volatile compounds, in particular those that still exhibit residual contamination, can be separated out during the process.A material processing device with a process unit, in particular an extruder, comprising i) at least one device for sampling volatile compounds during processing; ii) at least one analysis device for real-time or near-real-time analysis of the volatile compounds, wherein this analysis device is conductively connected to a sampling device; iii) a control device for the production, processing, or recycling process, configured to control parameters of the production, processing, or recycling process based on data obtained by the real-time or near-real-time analysis of volatile compounds. The device according to claim 16, wherein the process unit comprises at least one extruder, and at least one device for sampling volatile compounds is arranged upstream of the outlet nozzle of the extruder.The device according to claim 17, wherein the at least one analysis device for real-time analysis of the volatile compounds comprises a gas chromatogram and a detection unit. The device according to any one of claims 16 to 18, further comprising at least one device for introducing entraining and / or extraction agents into the process unit, in particular the extruder, arranged upstream of the extruder's outlet nozzle. The device according to any one of claims 16 to 19, wherein the sampling device is arranged at least at the last venting zone of an extruder and is conductively connected to a gas chromatogram. Furthermore, at least one vacuum pump is provided for generating a negative pressure for sampling and analysis and, if necessary, for removing volatile compounds from the processing in the extruder. The device according to any one of claims 16 to 20, wherein the device is a device for extruding plastics and / or plastic and composite recyclates.Device according to one of claims 16 to 21, wherein the control device is one which can control and regulate parameters of the processing method, in particular process parameters selected from temperature, speed, residence time, degree of filling, pressure profiles, amount and type of entraining agent or extraction agent, relative flow direction of the entraining agent or extraction agent in relation to the product flow and feed and removal position(s).

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