Hydrocarbon production method and apparatus

Abstract

The present invention provides a method for producing hydrocarbons, comprising the steps of: (S1) heat-treating organic waste to produce a first mixed gas; (S2) dry reforming the first mixed gas in a first fixed bed reactor to generate a second mixed gas; (S3) separating the second mixed gas into a first material flow containing carbon dioxide and a second material flow containing hydrogen and carbon monoxide; (S4) enabling the first material flow separated in the step (S3) to flow into a second fixed bed reactor, and converting the first material flow into carbon monoxide through a reverse Boudala reaction; (S5) mixing the second material flow with the carbon monoxide converted in the step (S4) to prepare a third mixed gas; (S6) generating a synthesis gas from the third mixed gas by a water-gas shift reaction; and (S7) producing hydrocarbons from the synthesis gas by catalytic reaction.

Description

Technical Field

[0001] This invention relates to a method and apparatus for preparing hydrocarbons from organic waste, and more specifically, to a method and apparatus for preparing hydrocarbons that can improve the yield of hydrocarbons prepared from organic waste and minimize carbon dioxide production. Background Technology

[0002] Organic waste can severely damage the environment during landfilling due to decomposition, requiring collection based on its specific characteristics and proper disposal through prescribed processes. However, simple disposal of organic waste necessitates the establishment of treatment facilities and consumes significant manpower, resulting in greater waste compared to production processes. Therefore, methods and technologies for recycling organic waste have been developed in recent years. A representative technology is the gasification process, which utilizes organic waste to produce syngas and convert it into high-value-added products for energy conversion.

[0003] Gasification typically refers to a series of processes that convert carbonaceous feedstocks such as coal, organic waste, and biomass into syngas containing hydrogen and carbon monoxide by reacting them with a supply of steam, oxygen, carbon dioxide, or a mixture thereof. In this case, "syngas" usually refers to a mixed gas generated through a gasification reaction that contains hydrogen and carbon monoxide, and may further contain carbon dioxide and / or methane.

[0004] Gasification technology has expanded to produce feedstocks and fuels for various compounds. For example, syngas can be used as a feedstock in the Fischer-Tropsch synthesis reaction to produce high-value-added products such as light oils, heavy oils, diesel fuel, waxes, aviation fuels, and lubricating oil bases. Furthermore, hydrogen from syngas, a major byproduct of gasification processes, is known to be used in hydrogen power generation, ammonia production, and oil refining processes. Methanol produced from syngas can also be used to obtain high-value-added chemical substances such as acetic acid, olefins, dimethyl ethers, aldehydes, fuels, and additives. However, the yield of syngas derived from organic waste is extremely low, making it difficult to efficiently produce high-value-added compounds from syngas.

[0005] In recent years, catalyst-based gasification processes have been developed for the production of syngas. However, the generation of coke and other contaminants during gasification leads to catalyst deactivation, causing process failures during continuous operation. Furthermore, to ensure economic viability, it is necessary to recover relatively expensive catalysts. However, recovering catalysts emitted in aggregated states such as coke requires multiple subsequent processes (such as air burning), resulting in a significant reduction in process efficiency.

[0006] Furthermore, conventional organic waste gasification processes suffer from significantly low yields of syngas, which can be converted into high-value-added products (below 30%), thus reducing productivity and limiting their application and commercialization. Moreover, while suppressing CO2 emissions is preferable from an environmental perspective, the gasification products of organic waste contain CO2 in addition to H2 and CO. This results in higher carbon dioxide emissions compared to landfill or pyrolysis treatments, potentially leading to further environmental pollution.

[0007] Therefore, there is a need for a method and apparatus for preparing hydrocarbons that can improve the yield of syngas that can be converted into high-value-added products during the gasification process of organic waste, thereby efficiently converting it into high-value-added hydrocarbons while minimizing the generation of carbon dioxide. Summary of the Invention

[0008] (a) Technical problems to be solved According to one aspect of the present invention, a method and apparatus for preparing hydrocarbons that significantly improves the yield of hydrocarbon preparation can be provided.

[0009] According to one aspect of the present invention, a method and apparatus for preparing hydrocarbons that minimizes the generation of carbon dioxide can be provided.

[0010] (II) Technical Solution The method for preparing hydrocarbons according to the present invention comprises the following steps: (S1) thermally treating organic waste to generate a first mixed gas; (S2) dry reforming the first mixed gas in a first fixed-bed reactor to generate a second mixed gas; (S3) separating the second mixed gas into a first feed stream containing carbon dioxide and a second feed stream containing hydrogen and carbon monoxide; (S4) feeding the first feed stream separated in step (S3) into a second fixed-bed reactor and converting it into carbon monoxide by a reverse boudouard reaction; (S5) mixing the second feed stream with the carbon monoxide converted in step (S4) to prepare a third mixed gas; (S6) generating syngas from the third mixed gas through a water-gas shift reaction; and (S7) generating hydrocarbons from the syngas through a catalytic reaction.

[0011] In one instance, the first mixed gas may further include one or more selected from landfill gas, shale gas, refinery waste gas, and biogas.

[0012] In one example, the second fixed-bed reactor can receive a carbon supply source from an external source.

[0013] In one instance, the first feed stream may contain more than 50% by volume carbon dioxide.

[0014] In one example, the C / O element ratio of the first mixed gas can be less than 0.8.

[0015] In one instance, step (S2) can be carried out on a composite catalyst with an active metal supported on a support.

[0016] In one example, the active metal may include one or more selected from nickel, vanadium, iron, platinum, palladium, and ruthenium.

[0017] In one example, the carrier may include one or more selected from silica, alumina, silica-alumina, carbon, zirconium oxide, titanium dioxide, zeolite, SAPO, and ALPO.

[0018] In one instance, step (S2) can be performed at a temperature of 700°C to 1000°C.

[0019] In one instance, step (S4) can be performed at a temperature of 600°C to 1000°C and a pressure of 50 kPa to 300 kPa.

[0020] In one example, the synthesis gas in step (S6) may contain hydrogen and carbon monoxide, wherein the ratio of hydrogen to carbon monoxide may be between 1.8:1 and 2.2:1.

[0021] In one instance, the organic waste in step (S1) may be selected from one or more of waste plastics, solid waste, biomass, waste oil, waste tires and metered garbage bags.

[0022] In one instance, prior to step (S2), a step of purifying the first mixed gas from step (S1) may be further included.

[0023] The hydrocarbon preparation apparatus according to the present invention comprises: a pyrolysis reactor that thermally treats organic waste to generate a first mixed gas; a first fixed-bed reactor that performs a dry reforming reaction on the first mixed gas under a catalyst to generate a second mixed gas; a carbon dioxide separation unit that separates the second mixed gas into a first feed stream containing carbon dioxide and a second feed stream containing hydrogen and carbon monoxide; a second fixed-bed reactor that converts the first feed stream into carbon monoxide via a reverse Boudouar reaction; a gas mixing unit that mixes the second feed stream with the carbon monoxide converted in the second fixed-bed reactor to prepare a third mixed gas; a syngas generation unit that converts the third mixed gas into syngas via a water-gas shift reaction; and a hydrocarbon conversion unit that converts the syngas into hydrocarbons via a catalytic reaction.

[0024] In one example, the second fixed-bed reactor may be connected between the carbon dioxide separation unit and the gas mixing unit, and the second fixed-bed reactor may include a second-first fixed-bed reactor and a second-second fixed-bed reactor connected in parallel.

[0025] In one example, the second fixed-bed reactor may further include a control unit for switching between the second-first fixed-bed reactor and the second-second fixed-bed reactor. The control unit can control the following modes: a first mode, in which the connection between the carbon dioxide separation unit, the second-first fixed-bed reactor, and the gas mixing unit is disconnected, causing the second-first fixed-bed reactor to regenerate and the reverse Boudouar reaction to proceed through the second-second fixed-bed reactor; or a second mode, in which the connection between the carbon dioxide separation unit, the second-second fixed-bed reactor, and the gas mixing unit is disconnected, causing the second-second fixed-bed reactor to regenerate and the reverse Boudouar reaction to proceed through the second-first fixed-bed reactor.

[0026] In one example, a refining unit may be further included between the pyrolysis reactor and the first fixed-bed reactor.

[0027] (III) Beneficial Effects According to one embodiment of the present invention, the yield of hydrocarbons prepared from organic waste can be significantly improved.

[0028] According to one embodiment of the present invention, the generation of carbon dioxide can be minimized during the preparation of hydrocarbons. Attached Figure Description

[0029] Figure 1 This is a schematic diagram illustrating a hydrocarbon preparation apparatus according to one example.

[0030] Figure 2 This is a schematic diagram of a hydrocarbon preparation apparatus including a refining unit, according to one example.

[0031] Figure 3 This is a schematic diagram illustrating a hydrocarbon preparation apparatus including a switchable reverse Boudouar reactor, according to one example.

[0032] Figure 4 A graph showing the methane conversion based on the dry reforming reaction time when preparing hydrocarbons according to an example method. Detailed Implementation

[0033] Unless otherwise specified, the singular form of the terms used in this specification may be interpreted to also include the plural form.

[0034] The numerical ranges used in this specification include lower and upper limits, as well as all values ​​within that range, all values ​​defined therein, and all possible combinations of upper and lower limits of numerical ranges defined in different forms. Unless otherwise specifically defined in this specification, values ​​outside the defined numerical range that may arise due to experimental error or rounding are also included within the defined numerical ranges.

[0035] The terms “comprising” or “including” used in this specification are open-ended expressions that have the same meaning as expressions such as “possessing,” “containing,” “having,” “characterized in,” etc., and do not exclude elements, materials, or processes not further listed.

[0036] Unless otherwise defined, the units of % used in this specification refer to weight unless otherwise specified.

[0037] Conventional catalytic gasification processes have been used to produce syngas. However, the generation of coke and other contaminants during gasification leads to catalyst deactivation, causing process failures during continuous operation. Furthermore, to ensure economic viability, relatively expensive catalysts need to be recovered. However, recovering catalysts emitted in a concentrated state, such as coke, requires multiple subsequent processes (e.g., air combustion), significantly reducing process efficiency. Moreover, conventional organic waste gasification processes have yielded syngas production rates significantly lower than 30%, reducing productivity and limiting the conversion into high-value-added products. In addition, environmental protection is paramount, minimizing CO2 emissions is preferable. However, in addition to H2 and CO, organic waste gasification products also contain CO2, resulting in higher CO2 emissions compared to landfill or pyrolysis treatments, potentially causing further environmental pollution. Therefore, the inventors of this invention have designed a method and apparatus for efficiently producing hydrocarbons from organic waste while minimizing CO2 generation.

[0038] This invention provides a method for preparing hydrocarbons, the method comprising the following steps: (S1) thermally treating organic waste to generate a first mixed gas; (S2) dry reforming the first mixed gas in a first fixed-bed reactor to generate a second mixed gas; (S3) separating the second mixed gas into a first feed stream containing carbon dioxide and a second feed stream containing hydrogen and carbon monoxide; (S4) feeding the first feed stream separated in step (S3) into a second fixed-bed reactor and converting it into carbon monoxide via a reverse Boudouar reaction; (S5) mixing the second feed stream with the carbon monoxide converted in step (S4) to prepare a third mixed gas; (S6) generating syngas from the third mixed gas via a water-gas shift reaction; and (S7) generating hydrocarbons from the syngas via a catalytic reaction.

[0039] Compared to existing gasification processes, the hydrocarbon preparation method according to the present invention can efficiently convert organic waste into syngas, thereby maximizing the yield of high-value-added hydrocarbons converted from syngas. Specifically, when reforming the gas derived from organic waste, the efficiency of the reforming reaction is improved by using a fixed-bed reactor with the highest conversion rate per unit mass of catalyst, thus increasing the yield of syngas and hydrocarbons. Furthermore, the generation of carbon dioxide during the hydrocarbon preparation process is minimized, thereby preventing environmental pollution.

[0040] The step (S1) is a step of thermally treating the organic waste to generate the first mixed gas, in which the gasification reaction of the organic waste can occur.

[0041] In one instance, the organic waste in step (S1) can be selected from one or more of waste plastics, solid waste, biomass, waste oil, waste tires, or metered garbage bags.

[0042] Specifically, step (S1) may be accompanied by one or more gasification reactions selected from the following reaction formulas 1 to 4.

[0043] [Reaction Formula 1] C x H y +H2O H2 + CO (water-coal gasification reaction) [Reaction 2] C x H y +CO2 CO (carbon dioxide vaporization reaction) [Reaction 3] CO + 3H2 CH4 + H2O (Methanation reaction) [Reaction 4] C x H y +O2 CO2 (oxidation reaction) In one example, the first mixed gas may contain methane, hydrogen, carbon monoxide and carbon dioxide, and may also contain various impurities such as water vapor, nitrogen oxides, sulfur oxides, and hydrogen chloride.

[0044] In one example, to increase the methane content in the first mixed gas composition, step (S1) can be carried out under first catalyst conditions or without a catalyst. Increasing the methane content in the first mixed gas composition can be advantageous in terms of methane reforming efficiency or syngas production yield. Therefore, to increase the methane content in step (S1), an acid-site catalyst or a molybdenum-based molding catalyst can be used as the bed material of the gasifier. Without a catalyst, the gasifier can be operated under low-temperature, high-pressure conditions to increase the methane content. Regarding the yield improvement effect of methane reforming, the same effect can be expected not only for the methane content but also for the C2 to C4 hydrocarbon content, and the C2 to C4 hydrocarbon content can also be increased by using an acid-site catalyst or by low-temperature, high-pressure gasification operation.

[0045] In one example, the first catalyst can be an acid-site catalyst or a molybdenum-based shaped catalyst. The acid-site catalyst can be alumina or a catalyst with solid acid sites derived from a structure. Alumina can be alumina alone, silica-alumina, or alumina dispersed in a carbon structure, etc., and the acid-site material can be zeolite, SAPO, AlPO, metal-organic framework (MOF), or its structural variations. A molybdenum-based catalyst refers to a catalyst in which molybdenum is supported on a support; nickel, cobalt, etc., can be added as needed, and tungsten can be used instead of molybdenum. The support can be a durable support capable of supporting active metals; for example, it can contain one or more substances selected from silica, alumina, silica-alumina, carbon, and zirconium oxide.

[0046] As another example of increasing the methane content in the first mixed gas, the first mixed gas may further contain one or more selected from landfill gas, shale gas, refinery waste gas, and biogas. The aforementioned landfill gas, shale gas, refinery waste gas, and biogas contain more than 40% by volume of methane and carbon dioxide, specifically, more than 50% by volume of methane and carbon dioxide. Therefore, by further containing the aforementioned gases, the first mixed gas has the effect of further improving the syngas production yield through subsequent methane reforming and reverse Boudouar reactions.

[0047] In one example, the upper limit of the C / O element ratio of the first mixed gas can be below 0.8, below 0.75, or below 0.7, and the lower limit can be above 0.1, above 0.2, or above 0.3. Specifically, the C / O element ratio can be from 0.1 to 0.8, and more specifically, from 0.3 to 0.7.

[0048] When the C / O ratio of the first mixed gas meets the above range, the oxygen content in the first mixed gas is higher than the carbon content when carrying out the following methane reforming reaction, which significantly reduces the amount of coke generated by side reactions and prevents catalyst deactivation, thereby enabling efficient methane reforming reaction.

[0049] In one instance, after step (S1), a further step of purifying the first mixed gas may be included.

[0050] The first mixed gas generated from the thermal treatment of organic waste may contain one or more impurities selected from tar, sulfur, nitrogen, and chlorine. Specifically, the first mixed gas may contain water-soluble impurities such as H2S, HCl, HOCl, and NH3, as well as non-water-soluble impurities such as tar. These impurities in the first mixed gas can cause catalyst deactivation, potentially reducing the efficiency of subsequent processes. Therefore, removing impurities from the first mixed gas and refining it can improve the overall process efficiency.

[0051] The method for purifying the first mixed gas can be selected from one or more combinations of high-pressure dust collection filters, water washing, alkaline solution washing, and passing through ceramic filters, but is not limited to these. When using water washing or alkaline solution washing, water-soluble impurities such as H2S, HCl, HOCl, and NH3 contained in the first mixed gas can be removed. When the first mixed gas is passed through ceramic filters or dust collection filters, non-water-soluble impurities such as tar and dust can be removed.

[0052] Step (S2) is a step of dry reforming the methane contained in the first mixed gas in the first fixed-bed reactor to prepare the second mixed gas. Step (S2) may be accompanied by a reforming reaction according to the following reaction formula 5.

[0053] [Reaction 5] CH4+CO2 2CO + 2H₂ (Carbon dioxide reforming reaction) The reforming reaction in step (S2) can be carried out at a temperature of 600°C to 1400°C and a pressure of 30 kPa to 2000 kPa.

[0054] Step (S2) can be performed without a catalyst, but can be performed using a catalyst to improve the reaction conversion rate at low temperatures of 600°C to 700°C. The catalyst for step (S2) can be a composite catalyst with an active metal supported on a carrier. The active metal can contain one or more selected from nickel, vanadium, iron, platinum, palladium, and ruthenium. Nickel, vanadium, or iron are commonly used as the active metal; however, when the impurity content in the raw materials, such as organic waste, is low during the heat treatment process, precious metals such as platinum, palladium, or ruthenium can be used.

[0055] In one example, the support may be a solid acid substance such as an oxide or zeolite. Specifically, the support may be one or more selected from ZSM-5, ZSM-11, USY zeolite, Ferrite, Mordenite, MCM-22, SUZ-4, L-type zeolite, silica, alumina, silica-alumina, carbon, zirconium oxide, and titanium dioxide.

[0056] By conducting the dry reforming reaction of methane in step (S2) in a fixed-bed reactor, the reforming efficiency of methane can be improved, thereby increasing the yield of hydrocarbons. Specifically, in the dry reforming process, the ratio of hydrogen to carbon monoxide as a product is close to 1:1, thus facilitating the catalytic reaction of syngas used in subsequent processes. Furthermore, by conducting the dry reforming of methane in a fixed-bed reactor, even if the methane content in the first mixed gas is low, methane can be effectively converted into hydrogen and carbon monoxide.

[0057] That is, by dry reforming the first mixed gas in a fixed-bed reactor in step (S2), not only can the yield of syngas be improved, but the hydrocarbon conversion reaction of syngas can also be carried out smoothly, thus improving the hydrocarbon preparation yield.

[0058] Step (S3) is to separate the second mixed gas into a first stream containing carbon dioxide and a second stream containing hydrogen and carbon monoxide.

[0059] In one example, the method for separating the second mixed gas into the first and second streams is not limited as long as it is a known method. However, in this invention, a carbon dioxide separation unit can be used for separation, which can be an amine scrubber. Typically, amine scrubbers use amine substances to bind and remove carbon dioxide, separating components such as carbon dioxide and hydrogen sulfide from gas vapors, and recovering gases containing hydrogen, carbon monoxide, or inert gases. Therefore, using an amine scrubber can separate the second mixed gas into the first and second streams.

[0060] As another example, the carbon dioxide separation unit can be a carbon capture and storage unit (CCS). When a CCS unit is used in the separation of carbon dioxide, the CCS unit can adsorb and separate carbon dioxide by utilizing one or more adsorbents selected from calcium oxide, calcium hydroxide, dolomite, limestone or natural alkali. Therefore, the CCS unit can be used to separate the second mixed gas into the first stream and the second stream.

[0061] The lower limit of the carbon dioxide content in the first feed stream can be 40% by volume or more, 50% by volume or more, or 60% by volume or more, and the upper limit of the carbon dioxide content in the first feed stream can be less than 99% by volume, less than 90% by volume, less than 80% by volume, or less than 70% by volume. Specifically, the first feed stream can contain 40% by volume to 99% by volume of carbon dioxide, and more specifically, it can contain 50% by volume to 80% by volume of carbon dioxide. In the carbon dioxide separation unit, when carbon dioxide is captured and then separated, in order to separate carbon dioxide with high purity, the regeneration tower in which carbon dioxide separation occurs in the adsorbent needs to be designed with a high number of trays, thus consuming more energy. Therefore, by having the first feed stream contain carbon dioxide within the above-mentioned range, the carbon dioxide separation process can be carried out under milder conditions.

[0062] Step (S4) involves converting the first feed stream separated in step (S3) into carbon monoxide via a reverse Boudouar reaction in the second fixed-bed reactor. By further converting the carbon dioxide contained in the first feed stream into carbon monoxide via the reverse Boudouar reaction, environmental pollution can be prevented by reducing carbon dioxide emissions, while simultaneously maximizing the yield of syngas. The reverse Boudouar reaction may be accompanied by the following reaction formula 6.

[0063] [Reaction Formula 6] C + CO2 2CO The step (S4) can be carried out at a temperature of 600°C to 1000°C and a pressure of 50 kPa to 300 kPa.

[0064] The reverse Boudouar reaction can be carried out by obtaining a carbon supply source from an external source. Specifically, the carbon supply source can be char derived from the organic waste, more specifically char derived from the pyrolysis of waste plastics or char derived from biomass. Alternatively, to avoid the possibility of introducing impurity gases through an external carbon supply source, high-purity graphite can be included.

[0065] By carrying out the reverse Boudouar reaction in step (S4) in a second fixed-bed reactor, carbon dioxide can be efficiently converted into carbon monoxide even if the first feed stream contains low-purity carbon dioxide.

[0066] In step (S2) of this invention, methane is dry-reformed in a first fixed-bed reactor, thus efficiently performing the dry reforming of methane using carbon dioxide contained in the first mixed gas as a reactant. Therefore, the carbon dioxide content in the second mixed gas converted from the first mixed gas and the first feed stream containing carbon dioxide originating from the second mixed gas is very low. Thus, for efficient conversion to carbon monoxide, it may be advantageous to carry out the reverse Boudouar reaction in a fixed-bed reactor with the highest conversion rate per unit weight of catalyst.

[0067] Step (S5) is to mix the second feed stream separated in the carbon dioxide separation unit with the carbon monoxide converted by the reverse Boudouar reaction in step (S4) to prepare the third mixed gas.

[0068] The third gas mixture may contain hydrogen and carbon monoxide.

[0069] Step (S6) is a process of adjusting the carbon monoxide to hydrogen ratio in the third mixed gas via a water-gas shift reaction to generate syngas. The third mixed gas can be converted via a water-gas shift reaction to achieve a hydrogen:carbon monoxide ratio suitable for a subsequent catalytic reaction. The water-gas shift reaction can be accompanied by the following reaction formula 7.

[0070] [Reaction Formula 7] CO + H₂O H2+CO2 The water-gas shift reaction can be carried out in the presence of a catalyst containing one or more metals selected from Fe, Cu, Zn, and Cr. The water-gas shift reaction can be carried out at temperatures ranging from 100°C to 400°C, specifically from 100°C to 300°C, and at bar levels ranging from 20 bar to 80 bar, specifically from 25 bar to 70 bar.

[0071] The hydrogen to carbon monoxide ratio in the syngas generated by the water-gas shift reaction can be from 1.5 to 3:1, specifically from 1.9 to 2.1:1. When the hydrogen to carbon monoxide ratio in the syngas meets the above range, the catalytic reaction for subsequent processes can proceed smoothly.

[0072] Step (S7) is the step of converting the syngas generated in step (S6) into hydrocarbon fractions, which can be converted into appropriate hydrocarbon fractions through catalytic reaction.

[0073] The catalytic reaction is not limited as long as it can convert syngas into hydrocarbon fractions, but it can specifically be a Fischer-Tropsch synthesis reaction or a methanol-olefin conversion reaction.

[0074] In one instance, when the catalytic reaction in step (S7) is a Fischer-Tropsch synthesis reaction, the syngas generated in step (S6) can be used as a raw material to carry out a reaction accompanied by the following reaction formula 8.

[0075] [Reaction Equation 8] nCO + 2nH2 C n H 2n +nH2O The Fischer-Tropsch synthesis reaction can be carried out in the presence of a catalyst containing cobalt, nickel or iron. The support may include alumina, silicon dioxide, titanium dioxide, etc., and the co-catalyst may include noble metals such as Pt, R, Re.

[0076] The Fischer-Tropsch synthesis reaction can be carried out at temperatures ranging from 100°C to 500°C, specifically from 200°C to 350°C, and at pressures ranging from 10 atm to 50 atm, specifically from 10 atm to 30 atm.

[0077] In one instance, when the catalytic reaction in step (S7) is a methanol-olefin conversion reaction, step (S7) may include: a reaction to convert syngas into methanol; and a reaction to convert methanol into olefins.

[0078] The reaction that converts syngas into methanol can be accompanied by the following reaction formula 9.

[0079] [Reaction Formula 9] CO + 2H2 CH3OH In one example, the reaction of converting syngas into methanol can be carried out under a Cu-based catalyst. Specifically, the Cu-based catalyst can be a Cu-based methanol synthesis catalyst, and the support for the Cu-based catalyst can be one or more selected from SiO2, ZrO2, Ga2O3, Al2O3, MgO, and TiO2. Specifically, the Cu-based methanol synthesis catalyst can be Cu / Zn / Al2O3.

[0080] The reaction of converting the synthesis gas into methanol can be carried out at 400°C to 600°C, specifically at 430°C to 530°C, and at 0.1 MPa to 10 MPa, specifically at 0.1 MPa to 5 MPa.

[0081] The reaction of methanol to olefins can be carried out under zeolite-based catalysts or AlPO4-based molecular sieve catalysts. Specifically, the molecular sieve-based catalyst can be ZSM-5, and the AlPO4-based catalyst can be a silica-aluminaphosphate (SAPO) molecular sieve catalyst, specifically selected from one or more of SAPO-5, SAPO-8, SAPO-11, SAPO-16, SAPO-17, SAPO-18, SAPO-20, SAPO-31, SAPO-34, SAPO-35, SAPO-44, and SAPO-46.

[0082] The reaction that converts methanol to olefins can be carried out at temperatures ranging from 200°C to 600°C, specifically from 300°C to 500°C, and at pressures ranging from 1 bar to 10 bar, specifically from 1 bar to 5 bar.

[0083] This invention provides a hydrocarbon preparation apparatus 1, comprising: a pyrolysis reactor 10, which heat-treats organic waste 100 to generate a first mixed gas 110; a first fixed-bed reactor 20, which performs a dry reforming reaction on the first mixed gas 110 under a catalyst to generate a second mixed gas 200; a carbon dioxide separation unit 30, which separates the second mixed gas 200 into a first feed stream 210 containing carbon dioxide and a second feed stream 211 containing hydrogen and carbon monoxide; and a second solid... The system includes a fixed-bed reactor 40, which converts the first feed stream 210 into carbon monoxide via a reverse Boudouar reaction; a gas mixing unit 50, which mixes the second feed stream 211 with the carbon monoxide converted in the second fixed-bed reactor 40 to prepare a third mixed gas 220; a syngas generation unit 60, which converts the third mixed gas 220 into syngas 230 via a water-gas shift reaction; and a hydrocarbon conversion unit 70, which converts the syngas 230 into hydrocarbons via a catalytic reaction.

[0084] The hydrocarbon preparation apparatus 1 according to the present invention, by using a fixed-bed reactor, can efficiently convert the first mixed gas 110 into syngas 230 and hydrocarbons, while significantly reducing carbon dioxide emissions, thus preventing environmental pollution. Furthermore, by using a fixed-bed reactor, which is easier to control and has lower equipment and operating costs compared to a fluidized-bed reactor, it offers the advantage of providing an economical process.

[0085] Reference Figure 1Organic waste 100 is introduced into pyrolysis reactor 10 and, after heat treatment, generates a first mixed gas 110. The first mixed gas 110 flows into the first fixed-bed reactor 20 and is converted into a second mixed gas 200 through a dry methane reforming reaction.

[0086] In one example, the hydrocarbon preparation apparatus may further include a refining unit 80 connected between the pyrolysis reactor 10 and the first fixed-bed reactor 20. Specifically, see... Figure 2 The first mixed gas 110 flows into the refining unit 80 to remove impurities, and the first mixed gas 120 after removing impurities is introduced into the first fixed-bed reactor 20, so that the methane reforming reaction can be carried out.

[0087] The refining unit 80 includes a sprayer for injecting liquid, receiving a first mixed gas 110 from the pyrolysis reactor 10, and contacting the first mixed gas 110 with water or a weakly alkaline solution containing sodium carbonate to remove water-soluble impurities such as H2S, HCl, HOCl and NH3. Alternatively, a high-pressure dust collector can be used to remove dust, and non-water-soluble impurities such as tar can be removed by means of a ceramic filter.

[0088] The second mixed gas 200 flows into the carbon dioxide separation unit 30 and is separated into a first feed stream 210 containing carbon dioxide and a second feed stream 211 containing hydrogen and carbon monoxide. The second feed stream 211 is directly supplied to the gas mixing unit 50, and the first feed stream 210 is supplied to the second fixed-bed reactor 40, thereby being converted into carbon monoxide through the reverse Boudouar reaction.

[0089] In one example, the second fixed-bed reactor 40 is connected between the carbon dioxide separation unit 30 and the syngas generation unit 60, as shown in the reference. Figure 3 The second fixed-bed reactor 40 may include a second-first fixed-bed reactor 41 and a second-second fixed-bed reactor 42 connected in parallel. Since the second fixed-bed reactor 40 includes the second-first fixed-bed reactor 41 and the second-second fixed-bed reactor 42, the reactors can be switched and used according to the catalyst activity of the fixed-bed reactors, thereby improving the overall process efficiency and enabling continuous operation of the process.

[0090] In another example, the second fixed-bed reactor 40 may further include a control unit (not shown) for switching between the second-first fixed-bed reactor 41 and the second-second fixed-bed reactor 42.

[0091] The control unit (not shown) can control the first mode, which disconnects the connection between the carbon dioxide separation unit 30, the second-first fixed bed reactor 41, and the syngas generation unit 60, so that the second-first fixed bed reactor 41 is regenerated and the reverse Boudouar reaction is carried out through the second-second fixed bed reactor 42.

[0092] Furthermore, the control unit (not shown) can control the second mode, which disconnects the connection between the carbon dioxide separation unit 30, the second-second fixed bed reactor 42, and the syngas generation unit 60, causing the second-second fixed bed reactor 42 to be regenerated, and the reverse Boudouar reaction to be carried out through the second-first fixed bed reactor 41.

[0093] The second fixed-bed reactor 40 can receive carbonized material, specifically carbonized material derived from organic waste, which can react with carbon dioxide to convert it into carbon monoxide. Non-limitingly, the carbonized material can be carbonized material derived from the pyrolysis of waste plastics or carbonized material derived from biomass.

[0094] The gas mixing unit 50 mixes the second feed stream 211 with the carbon monoxide converted in the second fixed-bed reactor 40 to prepare a third mixed gas 220. The third mixed gas 220 is supplied to the syngas generation unit 60, and the hydrogen:carbon monoxide ratio in the third mixed gas 220 is adjusted by a water-gas shift reaction, thereby converting it into syngas 230.

[0095] Syngas 230 can be introduced into hydrocarbon conversion unit 70 and converted into hydrocarbons through Fischer-Tropsch synthesis or methanol and olefin conversion, and recovered as high-value-added fractions.

[0096] In one example, when the hydrocarbon conversion unit 70 performs a methanol and olefin conversion reaction, the hydrocarbon conversion unit 70 may include a methanol conversion unit and an olefin conversion unit, wherein the methanol conversion unit receives syngas 230 and converts it into methanol, and the olefin conversion unit receives methanol from the methanol conversion unit and converts it into olefins.

[0097] In one example, the hydrocarbon preparation apparatus 1 may further include a separation unit connected to the hydrocarbon conversion unit 70, which separates the generated hydrocarbons into different fractions according to their boiling points by distillation.

[0098] The following describes specific embodiments of the present invention in further detail.

[0099] (Example 1) 1000g of municipal solid waste was added to a pyrolysis reactor, and then subjected to heat treatment with steam at 1200℃ and 250kPa under alumina beads to recover a first mixed gas with a C / O ratio of 0.69. The composition of the recovered first mixed gas is shown in Table 1 below.

[0100] [Table 1] The first mixed gas was cooled and added to a purification unit including a wet scrubber, where it was treated at 70°C and 100 kPa to remove impurities, and the purified first mixed gas was recovered. The composition of the impurity gases contained in the first mixed gas and the purified first mixed gas is shown in Table 2 below. As shown in Table 2, when the mixed gas was purified by the wet scrubber, no impurity gases such as NH3, HCl, H2S, and COS were detected, thus confirming that the impurities contained in the first mixed gas were effectively removed.

[0101] [Table 2] The refined first mixed gas was prepared at 2 L / g 催化剂(cat) • A space velocity of 1 hour is supplied to a first fixed-bed reactor containing 100 g of Ni / Al2O3 catalyst to prepare a second mixed gas by dry reforming methane. Specifically, in the first fixed-bed reactor filled with catalyst, H2 is supplied at 900 °C at a flow rate of 3.03 Nl / min and reduced for 2 hours. Then, the first mixed gas is supplied to the first fixed-bed reactor at a flow rate of 3.33 Nl / min, thereby carrying out the dry reforming reaction in a continuous process.

[0102] The Ni / Al2O3 catalyst was prepared by impregnating 1 mm diameter alumina particles in an aqueous solution of nickel nitrate hexahydrate dissolved in distilled water, followed by drying at 150 °C for 2 hours and then continuous calcination at 500 °C for 2 hours. This process was repeated multiple times as a unit process until the nickel content in the catalyst reached 20% by weight. The nickel content in the catalyst was measured by X-ray fluorescence spectrometry (XRF) analysis using Thermo Fisher Scientific's ARL QUANT' X.

[0103] The recovered second mixed gas, after water removal, flows into an amine scrubber. Carbon dioxide contained in the second mixed gas is captured by the amine scrubber, and the carbon dioxide-removed second mixed gas is separated into a second feed stream. Specifically, the second mixed gas flows into the first amine scrubber, where CO2 is captured using an aqueous solution of 12% by weight of NH3 dissolved in it (amine solution) at 50°C to 60°C, 10 to 20 bar, and a throughput of 0.5 Nl / h. The uncaptured gas is recovered as the second feed stream. The amine solution from the first amine scrubber flows into the second amine scrubber and is separated into amine solution and CO2 at 100°C. The CO2 is recovered as the first feed stream.

[0104] The recovered first feed stream was continuously fed into a second fixed-bed reactor filled with Ni / Al₂O₃ catalyst and 5 kg of high-purity graphite, where carbon dioxide was converted to carbon monoxide via a reverse Boudouar reaction. The reverse Boudouar reaction was conducted under N₂ gas conditions, at 750 °C, a CO₂ flow rate of 2.33 Nl / min, and a space velocity of 2.0 L / g. 催化剂 It is carried out under the condition of · hours.

[0105] Carbon monoxide converted from the first feed stream and the second feed stream separated from the amine scrubber flow into a gas mixing unit, where they are mixed at 200°C to prepare a third mixed gas. The third mixed gas flows into a syngas generation unit, where it is used to produce syngas with a H2:CO molar ratio of 2:1 via a water-gas shift reaction. The water-gas shift reaction is carried out at 165°C, 35 bar, and a space velocity of 1.4 L / g under a Cu / Zn / Al2O3 catalyst. 催化剂 The reaction was carried out under reaction conditions lasting for hours.

[0106] Syngas is supplied to the hydrocarbon conversion unit at a rate of 5000 L / kg under a cobalt / zinc oxide (Co / ZnO) catalyst. 催化剂 • The space velocity was set to an injection rate such that the volume ratio of carbon monoxide:hydrogen:argon was 63.2:31.3:5.5, and the Fischer-Tropsch synthesis reaction was carried out for 60 hours at a reaction temperature of 300°C and a pressure of 10 bar, and the hydrocarbon fraction was recovered.

[0107] (Comparative Example 1) The process was carried out using the same method as in Example 1, except that the reverse Boudouar reaction process of Example 1 was not performed, and hydrocarbons were prepared using a second mixed gas.

[0108] (Comparative Example 2) The process was carried out using the same method as in Example 1, except that the water-gas shift reaction in Example 1 was not performed, and hydrocarbons were prepared using a third mixed gas.

[0109] (Experimental Example 1) Evaluation of the performance of dry reforming When preparing hydrocarbons using the method of Example 1, the methane conversion rates based on the run time of the dry reforming process are shown in Table 3 below. Figure 4 The methane conversion rate was calculated using Equation 1 after analyzing the CH4 content in the second gas mixture emitted per hour. Gas composition analysis was performed using gas chromatography (GC), and the total amount of gas was confirmed using a gas meter. Specifically, quantification was performed using GC to calculate the selectivity of different gases, and the composition of each gas was analyzed using the total amount of gas confirmed by the gas meter.

[0110] [Formula 1] [Table 3] As shown in Table 3 and Figure 4 As shown, even with a 120-minute dry reforming process, the methane conversion rate does not decrease and remains above 97%. Excellent catalyst activity is maintained even during prolonged reactions, demonstrating that coke-induced catalyst deactivation can be significantly reduced even when using a fixed-bed reactor. Therefore, when preparing hydrocarbons using the method according to the present invention, dry reforming reactions can be carried out continuously in a fixed-bed reactor for extended periods.

[0111] (Experimental Example 2) Analysis of Gas Composition The compositions of the gases contained in the first mixed gas, the second mixed gas, the third mixed gas, and the syngas during the preparation of hydrocarbons using the methods of Example 1, Comparative Example 1, and Comparative Example 2 were analyzed and are shown in Table 4 below. The compositions of the major components contained in the hydrocarbons thus prepared were analyzed and are shown in Table 5. Gas composition analysis was performed using gas chromatography (GC) in the same manner as in Experimental Example 1, and the total amount of gas was confirmed using a gas meter. Specifically, quantification was performed by GC to calculate the selectivity of different gases, and the composition of each gas was analyzed by the total amount of gas confirmed by the gas meter.

[0112] [Table 4] [Table 5] As shown in Tables 4 and 5, when preparing hydrocarbons using the method of Example 1, the carbon dioxide contained in the second mixed gas is recovered and converted into carbon monoxide through the reverse Boudouar reaction process. Therefore, not only can the yield of the prepared hydrocarbons be increased, but also high-quality syngas and hydrocarbons can be obtained.

[0113] More specifically, referring to Table 4, the syngas of Example 1, prepared sequentially through dry reforming, reverse Boudouar reaction, and water-gas shift process, showed higher H2 and CO contents than CH4 and CO2 contents. Furthermore, with the increase in syngas production yield, the yield of hydrocarbon fractions (liquid) prepared using the syngas reached as high as 77.3 g. Therefore, the hydrocarbon preparation method of the present invention can produce high-value-added syngas and hydrocarbons in high yield from a mixed gas obtained by the pyrolysis of organic waste, while reducing greenhouse gas emissions, thus exhibiting excellent environmental pollution prevention effects.

[0114] On the other hand, in Comparative Example 1, the carbon dioxide contained in the second mixed gas was not recovered and converted into carbon monoxide via the reverse Boudouar reaction; instead, syngas and hydrocarbons were prepared from the second mixed gas. Therefore, compared to Example 1, the prepared syngas contained less H2 and CO, and contained a large amount of carbon dioxide. Consequently, the yield of the prepared hydrocarbon fraction (liquid) was 58.1 g, significantly lower than that of Example 1.

[0115] In Comparative Example 2, the water-gas conversion process was not performed, so the molar ratio of hydrogen and carbon monoxide in the third mixed gas could not be controlled. As a result, the hydrocarbons could not be successfully converted through the catalytic reaction, and the measured yield of the prepared hydrocarbon fraction (liquid) was as low as 62.8 g.

[0116] Therefore, in the preparation of hydrocarbons according to the method of the present invention, a dry reforming reaction and a reverse Boudouar reaction are carried out in a fixed-bed reactor, converting the mixed gas obtained by the reverse Boudouar reaction into water gas, thereby improving process efficiency and enabling the preparation of syngas and hydrocarbons in high yield. Specifically, the dry reforming process is carried out in a fixed-bed reactor to improve the reforming efficiency of methane, maintaining a high methane conversion rate even during long-term dry reforming reactions, thus enabling a continuous process. Simultaneously, the reverse Boudouar reaction is carried out in the fixed-bed reactor, thereby efficiently converting carbon dioxide in the mixed gas into carbon monoxide. In particular, the reverse Boudouar reaction separates carbon dioxide contained in the mixed gas and converts it into carbon monoxide, thus offering the advantage of reducing carbon dioxide emissions while producing a large amount of carbon monoxide. Furthermore, the syngas prepared by the water gas conversion process has a controlled ratio of hydrogen to carbon monoxide in the mixed gas, thus efficiently carrying out the catalytic reaction of the subsequent hydrocarbon preparation process, thereby significantly improving the yield of syngas and hydrocarbons.

[0117] As described above, the present invention has been illustrated with specific content and limited embodiments, but this is only provided to help to understand the present invention more fully. The present invention is not limited to the above embodiments, and those skilled in the art can make various modifications and variations based on these descriptions.

[0118] Therefore, the concept of this invention should not be limited to the illustrated embodiments, and all contents of the claims of this invention and those equivalent to or having equivalent variations thereof are within the scope of the concept of this invention.

[0119] [Explanation of reference numerals in the attached figures] 1: Hydrocarbon preparation apparatus; 10: Pyrolysis reactor 20: Fixed-bed reactor No. 1; 30: Carbon dioxide separation unit 40: Fixed-bed reactor No. 2; 41: Fixed-bed reactor No. 2-1 42: Fixed-bed reactor No. 2-2; 50: Gas mixing unit 60: Syngas generation unit; 70: Hydrocarbon conversion unit 80: Refining unit; 100: Organic waste 110: First gas mixture; 120: First gas mixture after impurity removal 200: Second mixed gas; 210: First feed stream 211: Second feed stream; 220: Third mixed gas stream 230: Syngas

Claims

1. A process for the production of hydrocarbons, wherein, The preparation method includes the steps of: (S1) thermally treating organic waste to produce a first mixed gas; (S2) dry reforming the first mixed gas in a first fixed bed reactor to produce a second mixed gas; (S3) separating the second mixed gas into a first stream containing carbon dioxide and a second stream containing hydrogen and carbon monoxide; (S4) flowing the first stream separated in the step (S3) into a second fixed bed reactor and converting into carbon monoxide by reverse Boudouard reaction; (S5) mixing the second stream with the carbon monoxide converted in the step (S4) to produce a third mixed gas; (S6) producing a synthesis gas from the third mixed gas by water gas shift reaction; and (S7) producing a hydrocarbon from the synthesis gas by catalytic reaction.

2. The method of making hydrocarbons according to claim 1, wherein, The first mixed gas further includes one or more selected from landfill gas, shale gas, refinery off-gas, and biogas.

3. The method of making hydrocarbons according to claim 1, wherein, The second fixed bed reactor receives a carbon supply source from the outside.

4. The method of making hydrocarbons according to claim 1, wherein, The first stream contains 50% by volume or more of carbon dioxide.

5. The method of making hydrocarbons according to claim 1, wherein, The C / O element ratio of the first mixed gas is 0.8 or less.

6. The method of making hydrocarbons according to claim 1, wherein, The step (S2) is performed under a composite catalyst in which an active metal is supported on a support.

7. The method of making hydrocarbons according to claim 6, wherein, The active metal includes one or more selected from nickel, vanadium, iron, platinum, palladium, and ruthenium.

8. The method of making hydrocarbons according to claim 6, wherein, The support includes one or more selected from silicon dioxide, aluminum oxide, silicon dioxide-aluminum oxide, carbon, zirconium oxide, titanium dioxide, zeolite, SAPO, and ALPO.

9. The method of making hydrocarbons according to claim 1, wherein, The step (S2) is performed at a temperature of 700°C to 1000°C.

10. The method of making hydrocarbons according to claim 1, wherein, The step (S4) is performed at a temperature of 600°C to 1000°C and a pressure of 50 KPa to 300 KPa.

11. The method of making hydrocarbons according to claim 1, wherein, The synthesis gas in the step (S6) contains hydrogen and carbon monoxide, and the ratio of the hydrogen to the carbon monoxide satisfies 1.8:1 to 2.2:

1.

12. The method of making hydrocarbons according to claim 1, wherein, The organic waste in the step (S1) is one or more selected from waste plastic, solid waste, biomass, waste oil, waste tire, and metered garbage bag.

13. The method of making hydrocarbons according to claim 1, wherein, Before the step (S2), further including a step of refining the first mixed gas of the step (S1).

14. A hydrocarbon production apparatus, wherein, The hydrocarbon production apparatus includes: a pyrolysis reactor that thermally treats organic waste to produce a first mixed gas; a first fixed bed reactor that dry reforms the first mixed gas under a catalyst to produce a second mixed gas; a carbon dioxide separation unit that separates the second mixed gas into a first stream containing carbon dioxide and a second stream containing hydrogen and carbon monoxide; a second fixed bed reactor that converts the first stream into carbon monoxide by reverse Boudouard reaction; a gas mixing unit that mixes the second stream with the carbon monoxide converted in the second fixed bed reactor to produce a third mixed gas; a synthesis gas generation unit that converts the third mixed gas into a synthesis gas by water gas shift reaction; and a hydrocarbon production unit that produces a hydrocarbon from the synthesis gas by catalytic reaction. a hydrocarbon conversion unit that converts the synthesis gas into hydrocarbons by a catalytic reaction.

15. The hydrocarbon production apparatus of claim 14, wherein, The second fixed bed reactor is connected between the carbon dioxide separation unit and the gas mixing unit, and includes a second-1 fixed bed reactor and a second-2 fixed bed reactor connected in parallel.

16. The hydrocarbon production apparatus of claim 15, wherein, The second fixed bed reactor further includes a control unit for switching the second-1 fixed bed reactor and the second-2 fixed bed reactor, The control unit controls the following modes: a first mode in which the connection of the carbon dioxide separation unit-second-1 fixed bed reactor-gas mixing unit is cut off, the second-1 fixed bed reactor is regenerated, and the reverse Boudouard reaction is performed by the second-2 fixed bed reactor; or a second mode in which the connection of the carbon dioxide separation unit-second-2 fixed bed reactor-gas mixing unit is cut off, the second-2 fixed bed reactor is regenerated, and the reverse Boudouard reaction is performed by the second-1 fixed bed reactor.

17. The synthetic gas production apparatus of claim 14, wherein, The hydrocarbon production apparatus further includes a refining unit between the pyrolysis reactor and the first fixed bed reactor.

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