System and method for treatment of a process gas

Abstract

According to an example aspect of the present invention, there is provided a system (1) comprising a liquid ring compressor (2) capable of pressurizing a process gas, wherein a stabilized liquid hydrocarbon product is utilized as a service liquid for the liquid ring compressor (2), a heat exchanger (3) capable of cooling and at least partially condensing a process gas and stabilized liquid hydrocarbon product mixture (14), a phase separator (4) comprising a water boot for separating water, wherein the system (1) is configured to transfer the process gas and stabilized liquid hydrocarbon product mixture (14) from the liquid ring compressor (3) via the heat exchanger (3) to the phase separator (4), wherein the phase separator (4) comprises a water outlet (20), a first gas outlet (5) for guiding at least one first non- condensable gas (6) out of the system (1) and a first liquid outlet (7) for guiding at least a part of a first liquid hydrocarbon product (8) to a stabilizing column (9) comprising a second gas outlet (10) for guiding at least one second non-condensable gas (11) out of the system (1) and a second liquid outlet (12) for guiding at least a part of the stabilized liquid hydrocarbon product (13) back to the liquid ring compressor (2).

Description

FIELD

[0001] The present invention relates to a system and method for treatment of a process gas. In particular, certain embodiments of the present invention relate to a system and method for treatment of a process gas obtained from a product comprising a gas from at least partially pyrolyzed polymer waste material, which product has been transferred to a condensing system arranged downstream of a pyrolysis reactor and providing the process gas.

[0002] Further, the present invention relates to an arrangement comprising a pyrolysis reactor, a condensing system capable of providing a process gas, and a system for treatment of the process gas. BACKGROUND

[0003] Polymers are used in a wide variety of products. The polymers are typically acquired through petroleum resources, which are considered non-renewable. In this connection, the need for a sustainable supply of raw material has arisen, as accumulation of polymer waste has been recognized as an environmental problem. As a consequence, polymer waste is often collected and sorted for recycling or thermal decomposition purposes. Environmental problems can be reduced by subsequent polymer waste material treatment and re-use of at least a part of the material. For example, polymer waste material can be treated by pyrolysis, i.e. by thermal decomposition of the polymer waste material at elevated temperatures in an inert atmosphere, in order to obtain a product comprising a gas from at least partially pyrolyzed polymer waste. Such treatment may, for example, take place in a pyrolysis reactor, such as a rotary kiln reactor, into which polymer waste is fed.

[0004] For example, document EP 4306618 Al discloses a system and method for treatment of polymer waste. The system comprises a hollow chamber comprising a first chamber and a second chamber, wherein the second chamber is rotatable or the first chamber and the second chamber are rotatable, a heating system configured to heat the second chamber or to individually heat the first chamber and the second chamber, a lance having at least one feed outlet, wherein the lance extends within the hollow chamber at least through the first chamber, and wherein the system is configured to feed polymer waste into the second chamber via the at least one feed outlet, and at least one injector capable of injecting at least one sweep fluid into the first chamber or into the first chamber and into the second chamber in order to form a fluid flow towards at least one gas outlet for collecting a product comprising the at least one sweep fluid and a gas from at least partially pyrolyzed polymer waste.

[0005] The product comprising a gas from at least partially pyrolyzed polymer waste is then treated in at least one condensation step to obtain gaseous and condensed products. At least one non-condensable gas, also called process gas, however might require further treatment after the at least one condensation step.

[0006] In view of the foregoing, it would be beneficial to provide a system and a method for treatment of a process gas. SUMMARY OF THE INVENTION

[0007] The invention is defined by the features of the independent claims. Some specific embodiments are defined in the dependent claims.

[0008] According to a first aspect of the present invention, there is provided a system comprising a liquid ring compressor capable of pressurizing a process gas, wherein a stabilized liquid hydrocarbon product is utilized as a service liquid for the liquid ring compressor, a heat exchanger capable of cooling and at least partially condensing a process gas and stabilized liquid hydrocarbon product mixture, a phase separator comprising a water boot for separating water, wherein the system is configured to transfer the process gas and stabilized liquid hydrocarbon product mixture from the liquid ring compressor via the heat exchanger to the phase separator, wherein the phase separator comprises a water outlet, a first gas outlet for guiding at least one first non-condensable gas out of the system and a first liquid outlet for guiding at least a part of a first liquid hydrocarbon product to a stabilizing column comprising a second gas outlet for guiding at least one second non condensable gas out of the system and a second liquid outlet for guiding at least a part of the stabilized liquid hydrocarbon product back to the liquid ring compressor.

[0009] Various embodiments of the first aspect may comprise at least one feature from the following bulleted list: • the liquid ring compressor is capable of pressurizing the process gas to a pressure in the range between 2 and 10 bar(a), for example 5.5 bar(a) or 6 bar(a) • the heat exchanger is capable of cooling the process gas and stabilized liquid hydrocarbon product mixture to a temperature in the range between 20°C and 60°C • the heat exchanger comprises at least one tube arranged in a shell structure, wherein water is utilized for cooling, or a plate type heat exchanger or an air cooler • the stabilizing column comprises a reboiler and an overhead condensing unit • the stabilizing column comprises internals, for example a packed bed with random or structured packing or a trayed column, a liquid distributor and a chimney tray • an operating pressure of the stabilizing column is in the range between 150 kPa(a) and 600 kPa(a), for example 300 kPa(a)

[0010] According to a second aspect of the present invention, there is provided an arrangement comprising a pyrolysis reactor, at least one condensing system capable of providing a process gas, and a system according to any one of claims 1-7, wherein the condensing system is arranged between the pyrolysis reactor and the system.

[0011] According to a third aspect of the present invention, there is provided a method comprising providing a liquid ring compressor capable of pressurizing a process gas, wherein a stabilized liquid hydrocarbon product is utilized as a service liquid for the liquid ring compressor, providing a heat exchanger capable of cooling and at least partially condensing a process gas and stabilized liquid hydrocarbon product mixture, providing a phase separator comprising a water boot for separating water, transferring the process gas and stabilized liquid hydrocarbon product mixture from the liquid ring compressor via the heat exchanger to the phase separator, wherein the phase separator comprises a water outlet, a first gas outlet for guiding at least one first non-condensable gas out of the system and a first liquid outlet for guiding at least a part of a first liquid hydrocarbon product to a stabilizing column comprising a second gas outlet for guiding at least one second noncondensable gas out of the system and a second liquid outlet for guiding at least a part of the stabilized liquid hydrocarbon product back to the liquid ring compressor, and guiding the stabilized liquid hydrocarbon product back to the liquid ring compressor.

[0012] Various embodiments of the third aspect may comprise at least one feature from the following bulleted list: • the method comprising pressurizing the process gas to a pressure in the range between 2 bar(a) and 10 bar(a), for example 5.5 bar(a) or 6 bar(a), by the liquid ring compressor • the method comprising cooling the process gas and stabilized liquid hydrocarbon product mixture to a temperature in the range between 20°C and 60°C by the heat exchanger, for example to 40°C • the method comprising heating of first liquid hydrocarbon product upstream of the stabilizing column • the method comprising utilizing at least a part of stabilized liquid hydrocarbon product obtained from the stabilizing column as the service liquid for the liquid ring compressor • the method comprising mixing the stabilized liquid hydrocarbon product with a heavier further hydrocarbon product

[0013] Considerable advantages are obtained by certain embodiments of the invention. A system and method for treatment of a process gas are provided, particularly for a process gas obtained from a product comprising a gas from at least partially pyrolyzed polymer waste material, which product has been transferred to a condensing system arranged downstream of a pyrolysis reactor and providing the process gas.

[0014] According to the present invention, utilizing a stabilized liquid hydrocarbon product as the service fluid of the liquid ring compressor results in absorbing valuable components from the compressed process gas, thus increasing liquid product yield of the process. The loss of hydrocarbons to the non-condensable gas streams exiting the system can be reduced. Further, a suitable vapor pressure or flash point for transport and storage of the obtained oil can be achieved. Further, the risk of a possible free water phase in the hydrocarbon product product can be avoided or at least reduced. Furthermore, the noncondensable gases exiting the system have less heavier hydrocarbons entrained. Additionally, at least one non-condensable gas at an elevated pressure can be provided for other downstream applications, for example as fuel or as feedstock. Pressurizing the process gas can also be beneficial for utilization of the stream in a direction downstream. Even further, a substantial waste water stream from the liquid ring compressor can be avoided by using a stabilized liquid hydrocarbon product as the service liquid of the liquid ring compressor. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIGURE 1 illustrates a schematic view of a system for treatment of a process gas in accordance with at least some embodiments of the present invention,

[0016] FIGURE 2 illustrates a schematic view of an arrangement in accordance with at least some embodiments of the present invention, and

[0017] FIGURE 3 illustrates a schematic view of another arrangement in accordance with at least some embodiments of the present invention. EMBODIMENTS

[0018] In FIGURE 1 a schematic view of a system 1 for treatment of a process gas 15 in accordance with at least some embodiments of the present invention is illustrated. The system 1 comprises a liquid ring compressor 2 or liquid ring pump capable of pressurizing a process gas 15. The process gas 15 may be obtained from the process shown in FIGURE 3, for instance. The process gas 15 comprises hydrocarbons predominantly C8 and below, hydrogen, nitrogen, carbon monoxide, carbon dioxide and steam. According to the present invention, a stabilized liquid hydrocarbon product is utilized as a service liquid for the liquid ring compressor 2. The stabilized liquid hydrocarbon product may be cooled prior to utilizing it as the service liquid. The process gas 15 may be, for example, obtained from a product comprising a gas from at least partially pyrolyzed polymer waste material, which product has been transferred to a condensing system arranged downstream of a pyrolysis reactor and providing the process gas 15. The pyrolysis reactor may be a rotary kiln reactor, for instance. The liquid ring compressor 2 is capable of pressurizing the process gas 15 to about 2 to 10 bar(a), for example 5.5 to 6 bar(a). The temperature of the process gas and stabilized liquid hydrocarbon product mixture may rise to approximately 60°C to 70°C in the liquid ring compressor 2, for instance.

[0019] The system 1 further comprises a heat exchanger 3 capable of cooling and partially condensing a process gas and a stabilized liquid hydrocarbon product mixture 14. The heat exchanger 3 may, for example, comprise at least one tube arranged within a shell structure, a plate type heat exchanger or an air cooler. The cooling medium may be air or water. The process gas and stabilized liquid hydrocarbon product mixture 14 from the liquid ring compressor 2 is able to flow through the tube. The heat exchanger 3 may, for example, operate with cooling water present in the shell structure. The heat exchanger may be, for example, capable of cooling the process gas and stabilized liquid hydrocarbon product mixture 14 to a temperature in the range between 20°C and 60°C. For example, the compressed two-phase flow from the liquid ring compressor 2 may be cooled to a temperature of 40°C. The service liquid works as an absorbent for the heavier components in the process gas 15. Gas and liquid are in phase equilibrium with each other at the discharge side.

[0020] Furthermore, the system 1 comprises a phase separator 4 comprising a water boot for separating any possible free water 21. After cooling, the process gas and stabilized liquid hydrocarbon product mixture 14 is led into the phase separator 4. In other words, the system 1 is configured to transfer the process gas and stabilized liquid hydrocarbon product mixture 14 from the liquid ring compressor 2 via the heat exchanger 3 to the phase separator 4. The phase separator 4 comprises a water outlet 20 for guiding water 21 out of the system 1, a first gas outlet 5 for guiding at least one first non-condensable gas 6 out of the system 1 and a first liquid outlet 7 for guiding at least a part of a separated first liquid hydrocarbon product 8 to a stabilizing column 9. Gaseous hydrocarbons and nonhydrocarbons such as hydrogen, nitrogen, carbon monoxide and carbon dioxide may be removed via the first gas outlet 5. Light first non-condensable gases 6, for example C4 and lighter hydrocarbons (C4 and lighter), may be directed to a fuel gas network via the first gas outlet 5 or other users, for instance. The slip stream may be sent to spillback. The spillback controls the liquid ring compressor 2 suction pressure.

[0021] The stabilizing column 9 comprises a second gas outlet 10 for guiding at least one second non-condensable gas 11 out of the system 1 and a second liquid outlet 12 for guiding at least a part of a stabilized second liquid hydrocarbon product 13 back to the liquid ring compressor 2. The stabilizing column 9 is typically provided to remove C4 and lighter components dissolved in the first liquid hydrocarbon product 8, i.e. the feed stream. Typically, the stabilizing column 9 comprises a stand pipe and a bottom sump with relevant connections for inlet and outlet process streams. The stabilizing column 9 may be further equipped with or connected to a reboiler and an overhead condenser, for instance. The overhead condenser may be an external, an integrated or a direct contact condenser. Light second non-condensable gases 11 may be directed to the fuel gas network via the second gas outlet 10 or other users, for instance. An operating pressure of the stabilizing column 9 may be dictated by an available or selected pressure of the liquid ring compressor 2, a downstream gas user requirement and / or available cold and hot utility temperature levels. The operating pressure of the stabilizing column 9 may be in the range between 150 kPa(a) and 600 kPa(a), for instance. The stabilized liquid hydrocarbon product 13 obtained from the stabilizing column 9 can be utilized as the service liquid for the liquid ring compressor 2.

[0022] Example:

[0023] According to an example, the operating pressure of the stabilizing column 9 is 300 kPa(a). An electrical reboiler heats a bottom circulation to about 142°C and a bottom sump temperature is approximately 132°C. The integrated overhead condenser operates with regular cooling water and cools the reflux stream to about 40°C.

[0024] According to a certain embodiment, internals of the stabilizing column 9 may include a packed bed with random packing or sieve trays, a liquid distributor, a chimney tray, and feed distributors for the column feed and reboiler return flow. A purpose of the chimney tray is to collect reflux in the form of hydrocarbon liquid dripping from the integrated overhead condenser and to distribute gas from the column's flash zone to an integrated overhead condenser. Separating and decanting any remaining water may also be possible.

[0025] The accessories of the stabilizing column 9 can be chosen based on required capacity and design criteria of the unit. For example, structured packing has a lower pressure drop, but can have limitations with small internal diameters of the stabilizing column 9. Utility types and a plant layout also have an effect on an equipment type selection. Upstream of the stabilizing column 9, there may be a feed-bottoms exchanger for heat integration purposes, for instance. The combined stream from the phase separator 4 and a condensing system, for example a quench tower, arranged upstream of the system 1 may be, for example, heated from about 40°C to approximately 98°C with the help of a hot stabilizer bottom stream. While heating the feed, part of it flashes and the two-phase flow is directed into flash zone, just under the reflux collector chimney tray.

[0026] The stabilized product then cools down to about 70°C in the feed-bottoms exchanger. The stabilized liquid hydrocarbon product, i.e. the bottom product of the stabilizing column 9, is typically produced to meet a specific product specification (vapor pressure). By stabilizing, most of the C4 and lighter hydrocarbon products are removed from the bottom product. In one embodiment, the stream may mainly contain naphthagrade material (approximately 90 wt% boiling point below 182 °C) and some heavier kerosene-grade material (approximately 10 wt% boiling point below 248 °C). The proportions depend on the feed quality and operating conditions. Part of the product in the form of oil is cooled down to 40°C in a product cooler and sent back to the liquid ring compressor 2 to serve as the service fluid. The stabilized oil can be mixed with a heavier oil cut to form a total oil product having suitable vapor pressure at a desired storage temperature. The heavier further hydrocarbon product may, in one embodiment, contain approximately 30 wt% hydrocarbons boiling below 180 °C, but this depends on the feed and operating conditions. A pour point of the total oil product dictates the storage temperature and an amount of oil that is bypassed through the product cooler. A typical storage temperature is 70°C.

[0027] The total oil product properties are: A suitable vapor pressure or flash point for the transport and storage of the oil. In this example, the suitable vapor pressure has been achieved by adjusting the 5 wt-% cut point of the light oil to 70°C. The mixing of the dry stabilized light oil with the heavier cut stream decreases a probability of having free water in the combined stream. In addition to the suitable vapor pressure or flash point and low water content, impurity levels of the LWP product can be controlled by choosing correct selection of waste plastics as the feedstock to the unit.

[0028] Non condensable gas products from the process have also favourable properties and benefits according to the disclosed process. As the gas phase is thoroughly mixed with the service fluid in the liquid ring compressor 2 and at least one remaining second non-condensable gas is obtained through evaporation in the stabilization column, solids content of the at least one second non-condensable gas is minimized. The at least one second non-condensable gas has also less heavier hydrocarbons entrained, mitigating fouling in combustion equipment or other equipment arranged downstream. Additionally, the stable quality gas is more suitable for further separation to e.g. LPG-type product fraction or use as petrochemical feedstock.

[0029] In FIGURE 2 a schematic view of an arrangement 16 in accordance with at least some embodiments of the present invention is illustrated. The arrangement 16 comprises a pyrolysis reactor 17, at least one condensing system 18 capable of providing a process gas 15, and a system 1 as described above in connection with FIGURE 1.

[0030] In FIGURE 3 a schematic view of another arrangement 16 in accordance with at least some embodiments of the present invention is illustrated. The arrangement 16 comprises a pyrolysis reactor 17, a condensing system 18 capable of providing a process gas 15, and a system 1 as described above in connection with FIGURE 1.

[0031] The condensing system 18 is typically arranged directly after or downstream of the pyrolysis reactor 17. The condensing system 18 comprises a first condensing unit 22. The first condensing unit 22 may be a quench tower, for instance. The first condensing unit 22 comprises a first gas inlet 23 for guiding a first product 24 comprising the pyrolysis gas into the first condensing unit 22. The pyrolysis gas is provided from the pyrolysis reactor 17. The first product 24 may, for example, comprise a gas from at least partially pyro lyzed polymer waste material. The first product 24 may additionally comprise other gases including purge gases, flush gases or sweeping gases utilized in the pyrolysis reactor, for instance. Further, the first condensing unit 22 comprises a first outlet 25 for guiding a condensed second product 26 out of the first condensing unit 22. The condensed second product 26 is typically a product comprising heavy hydrocarbons. Additionally, the first condensing unit 22 comprises a second outlet 27 for guiding a gaseous third product 28 out of the first condensing unit 22.

[0032] The condensing system 18 further comprises an overhead condensing unit 31. The condensing system 18 is configured to transfer the gaseous third product 28 to a second phase separator 35 via the overhead condensing unit 31. The second phase separator 35 may be a three-phase separation vessel, for instance. The gaseous third product 28 can be guided from the second outlet 27 of the first condensing unit 22 to a second gas inlet 30 of the overhead condensing unit 31 via a first piping system 29. The overhead condensing unit 31 comprises a heat exchanger capable of condensing the gaseous third product 28 at a temperature below 100 °C.

[0033] The condensing system 18 further comprises at least one water injection system arranged upstream of the heat exchanger of the overhead condensing unit 31. The at least one water injection system is capable of washing, cooling and at least partly condensing the gaseous third product 28 by contacting said gaseous third product 28 water. For example, the overhead condensing unit 31 comprises at least one tube arranged within a shell structure and the gaseous third product 28 is capable of flowing along the at least one tube. The at least one tube may be arranged vertically or substantially vertically. In such a case, the condensing system 18 is typically configured to guide the gaseous third product 28 along the at least one tube from a top of the overhead condensing unit 31. The water injection system comprises one or more spray nozzles capable of spraying water onto an inner surface of the at least one tube, onto a tube sheet of the overhead condensing system 31 and / or directly into a gas flow of the gaseous third product 28. Spraying water onto the inner surface of the at least one tube and / or the tube sheet may, for example, take place from on top or in an upper part of the overhead condensing unit 31, i.e. upstream of the heat exchanger, to enable proper washing of the at least one tube. Spraying water directly into the gas flow may, for example, take place by another water injection system comprising one or more spray nozzles centred in the first piping system 29, i.e. upstream of the overhead condensing unit 11. As a consequence, water can be injected in a downstream direction in a co-current way. A mixture of condensed oil and water injected by the at least one water injection system can exit the overhead condensing unit 31 via a fluid outlet 32 and flow along a second piping system 33 together with the remaining gaseous third product to the second phase separator 35 comprising a fluid inlet 34. Consequently, the first piping system 29 and / or the second piping system 33 is / are washed by the water flow. Salt formation on at least some components of the condensing system 18, and thus fouling can be therefore avoided or at least reduced. Further, water soluble impurities including HCI, NH3 and H2S can be scrubbed off from the stream of the gaseous third product. Sprayed water can also clean entrained solid particles from the incoming stream of the gaseous third product.

[0034] Water utilized in the injection of water typically consists of pyrolytic water generated in the pyrolysis reactions and added makeup water. A pyrolytic water stream is typically generated at the first injection point or in the overhead condenser itself and is later separated from the third product in a downstream separation step. Makeup water is added to control an impurity content of the washing water. Makeup water quality may meet specifications of a boiler feed water quality to mitigate at least one of corrosion, scaling, fouling and foaming, for instance. Makeup water within this document means that the water is essentially contaminant free. Sour water and / or process water is removed from the process in a downstream separation step.

[0035] According to some embodiments, the at least one tube of the overhead condensing unit 31 may be arranged vertically or substantially vertically and the gaseous third product 28 is capable of flowing along the at least one tube 31 from a bottom of the overhead condensing unit 31. According to certain other embodiments, it is also possible to arrange the at least one tube of the overhead condensing unit 31 horizontally or substantially horizontally.

[0036] The second phase separator 35 comprises a fluid inlet 34 through which the remaining gaseous third product and the water and oil mixture from the overhead condensing unit 31 can enter. The second phase separator 35 is capable of separating the remaining gaseous third product and the water and oil mixture to obtain a condensed fourth product comprising at least an aqueous phase 36 and a separated oil phase 37. Water 38 and oil 39 can be removed from the phase separator 35. Remaining process gases 15 such as non-condensable gases can be guided out of the condensing system 18 to the liquid ring compressor 2 of the system 1.

[0037] It is to be understood that the embodiments of the invention disclosed are not limited to the particular structures, process steps, or materials disclosed herein, but are extended to equivalents thereof as would be recognized by those ordinarily skilled in the relevant arts. It should also be understood that terminology employed herein is used for the purpose of describing particular embodiments only and is not intended to be limiting.

[0038] Reference throughout this specification to one embodiment or an embodiment means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Where reference is made to a numerical value using a term such as, for example, about or substantially, the exact numerical value is also disclosed.

[0039] As used herein, a plurality of items, structural elements, compositional elements, and / or materials may be presented in a common list for convenience. However, these lists should be construed as though each member of the list is individually identified as a separate and unique member. Thus, no individual member of such list should be construed as a de facto equivalent of any other member of the same list solely based on their presentation in a common group without indications to the contrary. In addition, various embodiments and examples of the present invention may be referred to herein along with alternatives for the various components thereof. It is understood that such embodiments, examples, and alternatives are not to be construed as de facto equivalents of one another, but are to be considered as separate and autonomous representations of the present invention.

[0040] Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the description, numerous specific details are provided, such as examples of lengths, widths, shapes, etc., to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention.

[0041] While the forgoing examples are illustrative of the principles of the present invention in one or more particular applications, it will be apparent to those of ordinary skill in the art that numerous modifications in form, usage and details of implementation can be made without the exercise of inventive faculty, and without departing from the principles and concepts of the invention. Accordingly, it is not intended that the invention be limited, except as by the claims set forth below.

[0042] The verbs “to comprise” and “to include” are used in this document as open limitations that neither exclude nor require the existence of also un-recited features. The features recited in dependent claims are mutually freely combinable unless otherwise explicitly stated. Furthermore, it is to be understood that the use of "a" or "an", that is, a singular form, throughout this document does not exclude a plurality. INDUSTRIAL APPLICABILITY

[0043] At least some embodiments of the present invention find industrial application in treatment of a process gas obtained from a product comprising a gas from at least partially pyrolyzed polymer waste material, which product has been transferred to a condensing system arranged downstream of a pyrolysis reactor and providing the process gas. REFERENCE SIGNS LIST 1            system 2            liquid ring compressor 3           heat exchanger 4           phase separator 5              first gas outlet 6            first non-condensable gas 7              first liquid outlet 8            first liquid hydrocarbon product 9            stabilizing column 10          second gas outlet 11          second non-condensable gas 12           second liquid outlet 13          second liquid hydrocarbon product 14          process gas and stabilized liquid hydrocarbon product mixture 15          process gas 16          arrangement 17           pyrolysis reactor 18          condensing system 19          product comprising a gas from at least partially pyro lyzed polymer waste 20          water outlet 21          water 22           first condensing unit 23            first gas inlet 24           first product 25            first outlet 26          second product 27          second outlet 28          third product 29          first piping system 30          second gas inlet 31          overhead condensing unit 32           fluid outlet 33          second piping system 34           fluid inlet 35          second phase separator 36         an aqueous phase 37          oil phase 38          water 39           oil CITATION LIST Patent Literature EP 4306618 Al

Claims

1. A system (1) comprising:- a liquid ring compressor (2) capable of pressurizing a process gas (15), wherein a stabilized liquid hydrocarbon product is utilized as a service liquid for the liquid ring compressor (2),- a heat exchanger (3) capable of cooling and at least partially condensing a process gas and the stabilized liquid hydrocarbon product mixture (14),- a phase separator (4) comprising a water boot for separating water,- wherein the system (1) is configured to transfer the process gas and stabilized liquid hydrocarbon product mixture (14) from the liquid ring compressor (3) via the heat exchanger (3) to the phase separator (4), wherein the phase separator (4) comprises a water outlet (20), a first gas outlet (5) for guiding at least one first noncondensable gas (6) out of the system (1) and a first liquid outlet (7) for guiding at least a part of a first liquid hydrocarbon product (8) to a stabilizing column (9) comprising a second gas outlet (10) for guiding at least one second noncondensable gas (11) out of the system (1) and a second liquid outlet (12) for guiding at least a part of the stabilized liquid hydrocarbon product (13) back to the liquid ring compressor (2).

2. The system (1) according to claim 1, wherein the liquid ring compressor is capable of pressurizing the process gas to a pressure in the range between 2 and 10 bar(a).

3. The system (1) according to claim 1 or 2, wherein the heat exchanger is capable of cooling the process gas and stabilized liquid hydrocarbon product mixture (14) to a temperature in the range between 20°C and 60°C.

4. The system (1) according to any one of claims 1-3, wherein the heat exchanger (3) comprises at least one tube arranged in a shell structure, wherein water is utilized for cooling, or a plate type heat exchanger or an air cooler.

5. The system (1) according to any one of claims 1-4, wherein the stabilizing column (9) comprises a reboiler and an overhead condensing unit.

6. The system (1) according to any one of claims 1-5, wherein the stabilizing column (9) comprises internals.

7. The system (1) according to any one of claims 1-6, wherein an operating pressure of the stabilizing column (9) is in the range between 150 kPa(a) and 600 kPa(a).

8. An arrangement (16) comprising:- a pyrolysis reactor (17),- at least one condensing system (18) capable of providing a process gas (15), and- a system (1) according to any one of claims 1-7, wherein the condensing system (18) is arranged between the pyrolysis reactor (17) and the system (1).

9. A method comprising:- providing a liquid ring compressor (2) capable of pressurizing a process gas, wherein a stabilized liquid hydrocarbon product is utilized as a service liquid for the liquid ring compressor (2),- providing a heat exchanger (3) capable of cooling and at least partially condensing a process gas and stabilized liquid hydrocarbon product mixture (14),- providing a phase separator (4) comprising a water boot for separating water,- transferring the process gas and stabilized liquid hydrocarbon product mixture (14) from the liquid ring compressor (3) via the heat exchanger (3) to the phase separator (4), wherein the phase separator (4) comprises a water outlet (20), a first gas outlet (5) for guiding at least one first non-condensable gas (6) out of the system (1) and a first liquid outlet (7) for guiding at least a part of a first liquid hydrocarbon product (8) to a stabilizing column (9) comprising a second gas outlet (10) for guiding at least one second non-condensable gas (11) out of the system (1) and a second liquid outlet (12) for guiding at least a part of the stabilized liquid hydrocarbon product (13) back to the liquid ring compressor (2), and- guiding the stabilized liquid hydrocarbon product (13) back to the liquid ring compressor (2).

10. The method according to claim 1, the method comprising pressurizing the process gas to a pressure in the range between 5.5 and 6 bar(a) by the liquid ring compressor (2).

11. The method according to claim 9 or 10, the method comprising cooling the process gas and stabilized liquid hydrocarbon product mixture (14) to a temperature in the range between 20°C and 60°C by the heat exchanger (3).

12. The method according to any one of claims 9-11, the method comprising heating of first liquid hydrocarbon product (8) upstream of the stabilizing column (9).

13. The method according to any one of claims 9-12, the method comprising utilizing at least a part of the stabilized liquid hydrocarbon product (13) obtained from the stabilizing column as the service liquid for the liquid ring compressor (2).

14. The method according to any one of claims 9-13, the method comprising mixing the stabilized liquid hydrocarbon product (13) with a heavier further hydrocarbon product.

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