Methods and systems for preparing jet fuel from Fischer-Tropsch synthesis intermediates

Abstract

This invention relates to a method and system for obtaining jet fuel (or aviation kerosene) from Fischer-Tropsch synthesis intermediates through deep processing. Specifically, this invention uses Fischer-Tropsch liquefied petroleum gas (LPG) and naphtha through reforming and / or aromatization and alkylation to obtain alkyl aromatic components, overcoming the shortcomings of the single-structure composition of Fischer-Tropsch oils while significantly increasing the yield of aviation kerosene components. The method according to this invention can produce high-quality aviation kerosene with advantages such as sulfur-free or extremely low sulfur content, high smoke point, and high calorific value, and can be used to prepare high-quality, ultra-clean aviation fuel.

Description

Technical Field

[0001] This invention belongs to the field of Fischer-Tropsch synthesis intermediate product processing, and relates to processing methods and systems for implementing Fischer-Tropsch synthesis intermediate products, specifically to methods and systems for obtaining jet fuel (or aviation kerosene) from Fischer-Tropsch synthesis intermediate products through deep processing. Background Technology

[0002] Traditional jet fuel is refined from petroleum, accounting for 4%-8% of total crude oil consumption. With the development of the aviation industry, the increasing demand for jet fuel and the dwindling petroleum resources will gradually create a contradiction. Furthermore, pollution emissions from aircraft engines during idling, takeoff, cruise, and landing are becoming increasingly prominent and have attracted widespread attention. Utilizing carbon-containing resources such as coal or biomass to produce high-quality jet fuel cleanly and efficiently through Fischer-Tropsch synthesis technology to replace some traditional petroleum feedstock has significant scientific and practical value.

[0003] Fischer-Tropsch synthesis technology typically refers to the process where carbon-containing feedstocks are gasified, converted, and purified to produce clean syngas (CO + H2), which is then converted into petroleum products using a Fischer-Tropsch synthesis unit. Fischer-Tropsch synthesis technology is characterized by a wide range of feedstocks, products that are virtually free of sulfur and nitrogen impurities, low aromatic content, and clean and environmentally friendly characteristics, enabling it to meet the growing demand for jet fuel and increasingly stringent environmental requirements. Fischer-Tropsch synthesis technology is one of the most realistic and feasible approaches to achieving the clean and efficient conversion and utilization of carbon-containing resources, considering market capacity and demand, centralized clean conversion and utilization, and future expansion applications.

[0004] Chinese patent CN107446618B discloses a method for hydrotreating Fischer-Tropsch synthetic oil. This method involves mixing Fischer-Tropsch synthetic oil with hydrogen and feeding it into a hydrocracking reactor. The reaction takes place under the action of a hydrocracking catalyst, the average pore size of which decreases along the flow direction of the stream. The hydrotreating effluent is separated into gas and liquid phases. The gas phase is recycled, while the liquid phase enters a fractionation tower. In the fractionation tower, naphtha, aviation kerosene (hereinafter also referred to as "jet fuel"), diesel oil, and tail oil are obtained, with the tail oil being recycled back to the hydrocracking reactor. However, this method has the following shortcomings: First, the Fischer-Tropsch intermediate oil contains olefins and oxygen-containing compounds such as alcohols, acids, ketones, and esters, and direct hydrocracking will affect the stability of the catalyst. Second, the jet fuel component obtained solely through hydrocracking has a low content of isomeric hydrocarbons, affecting the balance between jet fuel yield and freezing point.

[0005] US Patent 6309432B1 discloses a method for processing and upgrading Fischer-Tropsch synthetic oil. This method first divides the Fischer-Tropsch synthetic oil into light and heavy fractions at a cutoff point of 371°C. The light fraction (below 371°C) undergoes thermal and cold separation systems to obtain a 246°C-371°C fraction and a C5-246°C fraction. The 246°C-371°C fraction and the heavy fraction (above 371°C) are then passed through a hydroisomerization reactor. During olefin saturation and hydrodeoxygenation, n-alkanes undergo hydroisomerization and hydrocracking reactions, with the isomerization products mainly being monomethyl branched hydrocarbons. The C5-246°C fraction is not hydrotreated but is mixed with the products from the hydrocracking reactor and sent to a fractionation tower to obtain corresponding jet fuel fractions. However, because Fischer-Tropsch synthetic oil has a high oxygen and olefin content, direct contact with the isomerization catalyst can affect the catalyst's stability and operating cycle, and result in poor product quality.

[0006] Chinese patent CN104711019B discloses a system and method for producing jet fuel and diesel oil from Fischer-Tropsch synthetic oil. This process includes two parts: hydrorefining and hydrotreating. The Fischer-Tropsch synthetic oil is first mixed with hydrogen and then fed into a hydrorefining reactor. The product enters a fractionation tower; the naphtha fraction is used as feedstock for ethylene cracking, the diesel fraction enters a hydroisomerization reactor, and the tail oil enters a hydrocracking reactor. The products from the two reactors are mixed and then fed into a fractionation tower to obtain aviation kerosene and diesel products. The tail oil is then recycled to the hydrocracking reactor. However, this method uses the naphtha fraction for cracking to produce ethylene, which reduces the oil yield.

[0007] The aforementioned existing technologies reflect representative process methods for producing aviation kerosene from Fischer-Tropsch synthesis intermediates. Although they can all produce alkane aviation kerosene components, there is still considerable room for optimization in terms of the balance between aviation kerosene yield and aviation kerosene composition and properties. Summary of the Invention

[0008] To address the aforementioned problems in the prior art, this invention provides a method and system for obtaining high-quality jet fuel through deep conversion of Fischer-Tropsch synthesis intermediates. The method and system described in this invention are designed specifically for the compositional distribution and reaction characteristics of Fischer-Tropsch synthesis intermediates, enabling flexible production of high-quality aviation kerosene with yields exceeding 75%.

[0009] On one hand, the present invention provides a method for preparing aviation kerosene from Fischer-Tropsch synthesis intermediates, the method comprising:

[0010] (1) Stripping the intermediate product of Fischer-Tropsch synthesis to obtain stripped light component, stripped intermediate component and stripped heavy component;

[0011] (2) The stripped heavy components from step (1) are subjected to hydrorefining to obtain the hydrorefined product;

[0012] (3) The hydrorefined product from step (2) is subjected to a first fractionation to obtain LPGⅠ, naphthaⅠ, a first intermediate component and a first heavy component;

[0013] (4) The first intermediate component from step (3) is hydroisomerized to obtain the hydroisomerized product;

[0014] (5) The first heavy component from step (3) is subjected to hydrocracking to obtain hydrocracking products;

[0015] (6) The hydroisomers from step (4) and the hydrocracking products from step (5) are subjected to a second fractionation to obtain LPG II, naphtha II, aviation kerosene and cracking tail oil; wherein the cracking tail oil is returned to step (5) for hydrocracking reaction.

[0016] (7) One or more of LPGⅠ, naphthaⅠ, LPGⅡ, and naphthaⅡ are treated in one or more of the following ways: reforming, aromatization; and then the reformed product and / or aromatized product are alkylated together with at least a portion of the stripped light component and the stripped intermediate component to obtain the alkylated product, and returned to step (2) for hydrorefining.

[0017] In a preferred embodiment, step (7) may be selected from one or more of the following:

[0018] a. At least a portion of naphtha I and at least a portion of naphtha II are reformed to obtain reformed products; then at least a portion of stripped light components, at least a portion of stripped intermediate components and reformed products are alkylated together to obtain alkylated products, and returned to step (2) for hydrorefining.

[0019] b. At least a portion of LPG I, at least a portion of naphtha I, at least a portion of LPG II, and at least a portion of naphtha II are subjected to aromatization to obtain an aromatized product; then at least a portion of the stripped light component, at least a portion of the stripped intermediate component, and the aromatized product are subjected to alkylation to obtain an alkylated product, and then returned to step (2) for hydrogenation purification.

[0020] c. At least a portion of LPG I and at least a portion of LPG II are subjected to aromatization to obtain an aromatized product; at least a portion of naphtha I and at least a portion of naphtha II are subjected to reforming to obtain a reformed product; at least a portion of the stripped light component, at least a portion of the stripped intermediate component, the aromatized product and the reformed product are subjected to alkylation to obtain an alkylated product, and then returned to step (2) for hydrorefining.

[0021] On the other hand, the present invention provides a system for preparing aviation kerosene from Fischer-Tropsch synthesis intermediates, the system comprising: a stripping unit, an aromatization unit, a reforming unit, an alkylation unit, a hydrorefining unit, a hydroisomerization unit, a hydrocracking unit, and a first fractionation unit and a second fractionation unit.

[0022] The present invention has the following beneficial effects:

[0023] Compared with existing Fischer-Tropsch synthetic petroleum product processing technologies, the method described in this invention obtains alkyl aromatic components from Fischer-Tropsch liquefied petroleum gas and naphtha through reforming and / or aromatization and alkylation, thus overcoming the deficiency of the single composition and structure of Fischer-Tropsch synthetic petroleum gas and significantly improving the yield of jet fuel components. Furthermore, through flexible matching of process units and adjustment of operating parameters, jet fuel components with different compositions and properties can be produced, enhancing technological competitiveness.

[0024] The method according to the present invention can produce high-quality aviation kerosene, which has advantages such as being sulfur-free or having extremely low sulfur content, high smoke point and calorific value, and can be used to prepare high-quality ultra-clean aviation fuel. Attached Figure Description

[0025] The accompanying drawings are part of the specification and, together with the detailed description, provide a further explanation of the invention, but are not intended to limit the invention.

[0026] Figure 1 The present invention provides a schematic flowchart of a method for preparing aviation kerosene from Fischer-Tropsch synthesis intermediates, wherein step (7) is performed in manner (a).

[0027] Figure 2 The present invention provides a schematic flowchart of a method for preparing aviation kerosene from Fischer-Tropsch synthesis intermediates, wherein step (7) is performed in manner (b).

[0028] Figure 3 The present invention provides a schematic flowchart of a method for preparing aviation kerosene from Fischer-Tropsch synthesis intermediates, wherein step (7) is performed in manner (c). Detailed Implementation

[0029] The specific embodiments of the present invention will be described in detail below. The specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0030] In this invention, the term "Fischer-Tropsch synthesis intermediate" refers to a Fischer-Tropsch synthesis product containing more than C2, obtained from carbon-containing raw materials through gasification, conversion, purification, and Fischer-Tropsch synthesis reaction.

[0031] The term "aviation kerosene" refers to aviation fuel specially developed for the performance of aircraft engines and the safety of aircraft, mainly composed of hydrocarbon compounds of different fractions.

[0032] In one embodiment, the present invention provides a method for preparing aviation kerosene from Fischer-Tropsch synthesis intermediates, the method comprising:

[0033] (1) Stripping the intermediate product of Fischer-Tropsch synthesis to obtain stripped light component, stripped intermediate component and stripped heavy component;

[0034] (2) The stripped heavy components from step (1) are subjected to hydrorefining to obtain the hydrorefined product;

[0035] (3) The hydrorefined product from step (2) is subjected to a first fractionation to obtain LPGⅠ, naphthaⅠ, a first intermediate component and a first heavy component;

[0036] (4) The first intermediate component from step (3) is hydroisomerized to obtain the hydroisomerized product;

[0037] (5) The first heavy component from step (3) is subjected to hydrocracking to obtain hydrocracking products;

[0038] (6) The hydroisomers from step (4) and the hydrocracking products from step (5) are subjected to a second fractionation to obtain LPG II, naphtha II, aviation kerosene and cracking tail oil; wherein the cracking tail oil is returned to step (5) for hydrocracking reaction.

[0039] (7) One or more of LPGⅠ, naphthaⅠ, LPGⅡ, and naphthaⅡ are treated in one or more of the following ways: reforming, aromatization; and then the reformed product and / or aromatized product are alkylated together with at least a portion of the stripped light component and at least a portion of the stripped intermediate component to obtain an alkylated product, and returned to step (2) for hydrorefining.

[0040] In some embodiments, in step (7), at least a portion of LPG I, at least a portion of naphtha I, at least a portion of LPG II and / or at least a portion of naphtha II may be aromatized; or, at least a portion of naphtha I and / or at least a portion of naphtha II may be reformed.

[0041] In some embodiments, in step (7), all or part of LPG I, all or part of naphtha I, and all of LPG II and / or all of naphtha II may be aromatized; or, all or part of naphtha I and / or all of naphtha II may be reformed.

[0042] In some preferred embodiments, in step (7), all or part of LPGⅠ, all or part of naphthaⅠ, and all of LPGⅡ and / or all of naphthaⅡ may be aromatized, and then the aromatized product is alkylated together with stripped light components and stripped intermediate components to obtain alkylated products, and then returned to step (2) for hydrorefining.

[0043] In some preferred embodiments, in step (7), all or part of naphtha I and all of naphtha II may be reformed, and then the reformed product may be alkylated together with stripped light components and stripped intermediate components to obtain alkylated products, which are then returned to step (2) for hydrorefining.

[0044] In some preferred embodiments, in step (7), all or part of LPG I and all of LPG II may be aromatized, and all or part of naphtha I and / or all of naphtha II may be reformed. Then, the reformed product and / or aromatized product may be alkylated together with stripped light components and stripped intermediate components to obtain alkylated products, which are then returned to step (2) for hydrorefining.

[0045] In a preferred embodiment, step (7) may be selected from one or more of the following:

[0046] a. At least a portion of naphtha I and at least a portion of naphtha II are reformed to obtain reformed products; then at least a portion of stripped light components, at least a portion of stripped intermediate components and reformed products are alkylated together to obtain alkylated products, and returned to step (2) for hydrorefining.

[0047] b. At least a portion of LPG I, at least a portion of naphtha I, at least a portion of LPG II, and at least a portion of naphtha II are subjected to aromatization to obtain an aromatized product; then at least a portion of the stripped light component, at least a portion of the stripped intermediate component, and the aromatized product are subjected to alkylation to obtain an alkylated product, and then returned to step (2) for hydrogenation purification.

[0048] c. At least a portion of LPG I and at least a portion of LPG II are subjected to aromatization to obtain an aromatized product; at least a portion of naphtha I and at least a portion of naphtha II are subjected to reforming to obtain a reformed product; at least a portion of the stripped light component, at least a portion of the stripped intermediate component, the aromatized product and the reformed product are subjected to alkylation to obtain an alkylated product, and then returned to step (2) for hydrorefining.

[0049] In a preferred embodiment, step (7) may be selected from one or more of the following:

[0050] All or part of naphtha I and all of naphtha II are reformed to obtain reformed products; then stripped light components, stripped intermediate components and reformed products are alkylated together to obtain alkylated products, and returned to step (2) for hydrorefining.

[0051] All or part of LPG I, all or part of naphtha I, all of LPG II, and all of naphtha II are subjected to aromatization to obtain aromatized products; then, the stripped light component, the stripped intermediate component, and the aromatized products are subjected to alkylation to obtain alkylated products, which are then returned to step (2) for hydrorefining; or

[0052] All or part of LPGⅠ and all of LPGⅡ are subjected to aromatization reaction to obtain aromatized products; all or part of naphthaⅠ and all of naphthaⅡ are subjected to reforming reaction to obtain reformed products; stripped light components, stripped intermediate components, aromatized products and reformed products are subjected to alkylation reaction to obtain alkylated products, and then returned to step (2) for hydrogenation purification.

[0053] In this invention, the "stripped light component" is a component with a distillation temperature of <36°C, which mainly contains C3-C4 hydrocarbons.

[0054] In this invention, the "stripping intermediate component" is a component with a distillation temperature of 36℃-130℃, which mainly contains C5-C8 hydrocarbons.

[0055] In this invention, "stripping heavy components" are components with a distillation range temperature >130°C, which mainly contain C9+ hydrocarbons.

[0056] In step (1), exemplary conditions for stripping may be: top temperature 90℃-180℃, bottom temperature 220℃-300℃, pressure 0.01Mpa-0.06Mpa, and theoretical plate number 10-20. In step (1), the stripping may be carried out in a stripping column.

[0057] In step (2), the hydrorefining is carried out under the action of a hydrorefining catalyst. For example, the hydrorefining catalyst comprises a support and an active metal supported on the support, wherein the support comprises alumina and / or silica-alumina, preferably γ-Al2O3; the active metal comprises one or more of noble metals (e.g., Pt, Pd, etc.), Group VIB non-noble metals, or Group VIII non-noble metals, preferably one or more of Mo, W, Co, and Ni (e.g., Ni-W).

[0058] Preferably, the hydrorefining reaction may include one or more catalyst beds, for example, one, two or three catalyst beds.

[0059] In some embodiments, each catalyst bed may be packed with the same or different types of hydrorefining catalysts. Preferably, when using a hydrorefining catalyst for a hydrorefining reaction, various hydrorefining catalyst protectants known to those skilled in the art may be packed, and the hydrorefining reaction may include one or more catalyst beds. In some embodiments, each catalyst bed may be packed with the same or different types of hydrorefining catalysts and / or hydrorefining catalyst protectants.

[0060] In step (2), the exemplary conditions for the hydrorefining may be: a reaction temperature of 150℃-400℃, preferably 250℃-350℃ (e.g., 250℃, 260℃, 270℃, 280℃, 300℃, etc.); a reaction pressure of 2-12 MPa, preferably 4-10 MPa (e.g., 4 MPa, 5 MPa, 6 MPa, 7 MPa, 8 MPa, 9 MPa, or 10 MPa); a hydrogen-to-oil volume ratio of (300-1500):1, preferably (400-800):1 (e.g., 400:1, 500:1, 600:1, 700:1, or 800:1); and a volume hourly space velocity of 0.1-5 h⁻¹. -1 Preferably 0.5-3h -1 (e.g., 0.5h) -1 1.0h -1 1.5h -1 2.0h -1 2.5h -1 , or 3h -1 ).

[0061] In some embodiments, for example, the hydrorefining reaction can be carried out in a fixed-bed reactor.

[0062] In this invention, "LPGⅠ" is a component with a distillation temperature of <36°C, which mainly contains C3-C5 hydrocarbons.

[0063] In this invention, "naphtha I" is a component with a distillation range of 36℃-130℃, which mainly contains C6-C8 hydrocarbons.

[0064] In this invention, the "first intermediate component" is a component with a distillation temperature of 130℃-300℃, which mainly contains C9-C16 hydrocarbons.

[0065] In this invention, the "first heavy component" is a component with a distillation range temperature > 300°C, which mainly contains C17+ hydrocarbons.

[0066] In step (3), exemplary conditions for the first fractionation may be: a top temperature of 50°C-150°C, preferably 100°C-140°C (e.g., 100°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, or 138°C), and a bottom temperature of 250°C-350°C, preferably 270°C-310°C (e.g., 270°C, 275°C, 280°C, 285°C, 290°C, 295°C). 300℃, 301℃ or 305℃), pressure 0.01-0.15MPa, preferably 0.10MPa-0.15MPa (e.g. 0.10MPa, 0.11MPa, 0.12MPa, 0.13MPa, 0.14MPa or 0.15MPa), theoretical plate number 20-30 (e.g. 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30).

[0067] In step (4), the hydroisomerization reaction is carried out in the presence of a hydroisomerization catalyst. For example, the hydroisomerization catalyst comprises a support and an active metal supported on the support, wherein preferably, the support comprises one or more of Beta, USY, ZSM-22, SAPO-11, ZSM-23, ZSM-35 molecular sieve supports or amorphous silicon, preferably one or more of Beta, USY, ZSM-22, SAPO-11, ZSM-23, ZSM-35 molecular sieve supports; the active metal comprises one or more of Group VIB non-noble metals and Group VIII metals, preferably one or more of Ni, Co, Mo, and W (e.g., Ni-W).

[0068] In step (4), the exemplary conditions for the hydroisomerization may be: a reaction temperature of 260℃-380℃, preferably 280℃-375℃, more preferably 280℃-360℃ (e.g., 280℃, 290℃, 300℃, 310℃, 320℃, 330℃, 340℃, 350℃, or 360℃); a reaction pressure of 1-8 MPa, preferably 2-6 MPa (e.g., 2 MPa, 3 MPa, 4 MPa, 5 MPa, or 6 MPa); a hydrogen-to-oil volume ratio of (300-1000):1, preferably (400-800):1 (e.g., 400:1, 500:1, 600:1, 700:1, or 800:1); and a volume hourly space velocity of 0.1-5 h⁻¹. -1 Preferably 0.5-3h -1 (e.g., 0.5h) -1 1.0h -1 1.5h -1 2.0h -1 2.5h -1 , or 3h -1 ).

[0069] In a preferred embodiment, the hydroisomerization can be carried out in a fixed-bed reactor.

[0070] In step (5), the hydrocracking is carried out in the presence of a hydrocracking catalyst. For example, the hydrocracking catalyst comprises a support and an active metal supported on the support. Preferably, the support may include one or more of alumina, silica, amorphous silica-alumina, Y, USY, Beta, MCM-41, and Y-Beta composite molecular sieves, or amorphous alumina and / or silica-alumina, preferably amorphous silica-alumina and a molecular sieve support (e.g., USY molecular sieve). The active metal may include one or more of Group VIB and / or Group VIII non-noble metals, preferably one or more of Ni, Co, Mo, and W (e.g., Ni-W).

[0071] In step (5), the exemplary conditions for the hydrocracking may be: a reaction temperature of 260℃-380℃, preferably 280℃-375℃, more preferably 280℃-350℃ (e.g., 280℃, 285℃, 290℃, 295℃, 300℃, 305℃, 310℃, 315℃, 320℃, 325℃, 330℃, 335℃, 340℃, 345℃ or 350℃). The reaction pressure is 1-8 MPa, preferably 2-6.5 MPa (e.g., 2 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa or 6.5 MPa); the hydrogen-to-oil volume ratio is (300-1000):1, preferably (400-800):1 (e.g., 400:1, 500:1, 600:1, 700:1 or 800:1); the volume hourly space velocity is 0.1-5 h⁻¹. -1 Preferably 0.5-3h -1 (e.g., 0.5h) -1 1.0h -1 1.5h -1 2.0h -1 2.5h -1 , or 3h -1 ).

[0072] In a preferred embodiment, the hydrocracking can be carried out in a fixed-bed reactor.

[0073] In this invention, "LPGⅡ" is a component with a distillation temperature of <36°C, which mainly contains C3-C5 hydrocarbons.

[0074] In this invention, "naphtha II" is a component with a distillation range of 36℃-130℃, which mainly contains C6-C8 hydrocarbons.

[0075] In this invention, "aviation kerosene" is a component with a distillation temperature of 130℃-300℃, which mainly contains C9-C16 hydrocarbons.

[0076] In this invention, "cracked tail oil" is a component with a distillation temperature >300°C, which mainly contains C17+ hydrocarbons.

[0077] In step (6), the conditions for the second fractionation may be: a top temperature of 30°C-150°C, preferably 100°C-150°C (e.g., 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 137°C, or 140°C); and a bottom temperature of 250°C-350°C, preferably 270°C-310°C (e.g., 270°C, 275 ... Temperatures: 80℃, 285℃, 290℃, 295℃, 300℃, 301℃, or 305℃; Pressure: 0.01-0.15MPa, preferably 0.10MPa-0.15MPa (e.g., 0.10MPa, 0.11MPa, 0.12MPa, 0.13MPa, 0.14MPa, or 0.15MPa); Theoretical plate number: 20-30 (e.g., 26).

[0078] In step (7), all or part of the LPGⅠ is subjected to an aromatization reaction, specifically the proportion of LPGⅠ subjected to the aromatization reaction to the total LPGⅠ is 5%-100%.

[0079] In step (7), all or part of the LPG ⅠI is subjected to an aromatization reaction, specifically the proportion of LPG ⅠI undergoing the aromatization reaction to the total LPG ⅠI is 5%-100%.

[0080] In step (7), all or part of the naphtha I is subjected to aromatization or reforming reaction, specifically the proportion of naphtha I subjected to aromatization or reforming reaction to the total naphtha I is 10%-100%.

[0081] In step (7), all or part of the naphtha Ⅱ is subjected to aromatization or reforming reaction, specifically the proportion of naphtha Ⅱ subjected to aromatization or reforming reaction to the total naphtha Ⅰ is 10%-100%.

[0082] In step (7), the reforming reaction is carried out under the action of a reforming catalyst. For example, the reforming catalyst includes a bifunctional reforming catalyst and a non-acidic reforming catalyst. Preferably, the bifunctional reforming catalyst is selected from Pt-Sn / Al2O3-Cl. - Pt-Re / Al2O3-Cl -One or more of the following: the non-acidic reforming catalyst is selected from one or more of Pt / KL, Pt / Kβ, Pt / KY, Pt-Sn / KL, and Pt-Re / KL.

[0083] In step (7), exemplary conditions for the reforming reaction may be: a reaction temperature of 250℃-550℃, preferably 280℃-500℃ (e.g., 300℃, 350℃, 400℃, 450℃, 480℃); a reaction pressure of 0.1-4MPa, preferably 0.35-3MPa (e.g., 0.5MPa, 1MPa, 1.5MPa, 2.0MPa, 2.5MPa, 3.0MPa); a hydrogen-to-oil volume ratio of (300-1000):1, preferably (400-800):1; and a volume hourly space velocity of 0.1-5h. -1 Preferably 0.5-3h -1 (e.g., 0.5h) -1 1.0h -1 1.2h -1 1.5h -1 2.0h -1 2.5h -1 , or 3h -1 ).

[0084] In some embodiments, the reforming reaction is carried out in a fixed-bed reactor.

[0085] In step (7), the aromatization reaction is carried out under the action of an aromatization catalyst. For example, the aromatization catalyst includes Zn and Ga modified ZSM-5, ZSM-11, etc.

[0086] In step (7), exemplary conditions for the aromatization reaction may be: a reaction temperature of 250℃-550℃, preferably 280℃-540℃ (e.g., 300℃, 320℃, 350℃, 380℃, 400℃, 420℃, 450℃, 480℃, 500℃, 520℃, 535℃); a reaction pressure of 0.1-4MPa, preferably 0.3-3MPa (0.3, 0.5, 0.8, 1.0, 1.5, 1.8, 2.0, 2.5 or 3MPa); and a volume hourly space velocity of 0.1-5h. -1 Preferably 0.5-3h -1 (0.5h -1 1.0h -1 1.2h -1 1.5h -1 2.0h -1 2.5h -1 , or 3h -1 ).

[0087] In some embodiments, the aromatization reaction is carried out in a fixed-bed or fluidized-bed reactor.

[0088] In step (7), the alkylation reaction is carried out under the action of an alkylation catalyst. For example, the alkylation catalyst may include liquid acids such as H2SO4, solid acids such as AlCl3, molecular sieves such as Beta, ZSM-5, MOR, USY, and MCM-22, as well as one or more of solid phosphoric acid, heteropoly acids, and solid superacids; preferably one or more of molecular sieves and solid superacids.

[0089] In step (7), exemplary conditions for the alkylation reaction may be: a reaction temperature of 100°C-350°C, preferably 120°C-280°C (e.g., 130°C, 140°C, 150°C, 180°C, 220°C, or 250°C); a reaction pressure of 1-8 MPa, preferably 2-6 MPa (e.g., 2 MPa, 3 MPa, 4 MPa, 5 MPa, or 6 MPa); and a volume hourly space velocity of 0.1-5 h⁻¹. -1 Preferably 0.5-3h -1 (For example, 0.5h) -1 1.0h -1 1.5h -1 2.0h -1 2.5h -1 , or 3h -1 ).

[0090] In some embodiments, the alkylation reaction is carried out in a fixed-bed reactor. In the most preferred embodiment, the alkylated product obtained by the alkylation reaction in step (7) conforms to the composition of aviation kerosene and can therefore be directly separated.

[0091] On the other hand, the present invention provides a system for preparing high-quality jet fuel from Fischer-Tropsch synthesis intermediates, the system comprising: a stripping unit, an aromatization unit, a reforming unit, an alkylation unit, a hydrorefining unit, a hydroisomerization unit, a hydrocracking unit, and first and second fractionation units.

[0092] In some embodiments, the system may further include a Fischer-Tropsch synthesis unit, which is a fixed-bed, fluidized-bed, or slurry-bed reactor.

[0093] In some embodiments, the stripping unit is a stripping tower. In some embodiments, the aromatization unit is a fixed-bed or fluidized-bed reactor. In some embodiments, the reforming unit is a fixed-bed reactor. In some embodiments, the alkylation unit is a fixed-bed reactor. In some embodiments, the hydrorefining unit is a fixed-bed reactor. In some embodiments, the hydroisomerization unit is a fixed-bed reactor. In some embodiments, the hydrocracking unit is a fixed-bed reactor.

[0094] The content of this invention can be illustrated by way of example through the description in the following numbered paragraphs:

[0095] 1. A method for preparing aviation kerosene from Fischer-Tropsch synthesis intermediates, the method comprising:

[0096] (1) Stripping the intermediate product of Fischer-Tropsch synthesis to obtain stripped light component, stripped intermediate component and stripped heavy component;

[0097] (2) The stripped heavy components from step (1) are subjected to hydrorefining to obtain the hydrorefined product;

[0098] (3) The hydrorefined product from step (2) is subjected to a first fractionation to obtain LPGⅠ, naphthaⅠ, a first intermediate component and a first heavy component;

[0099] (4) The first intermediate component from step (3) is hydroisomerized to obtain the hydroisomerized product;

[0100] (5) The first heavy component from step (3) is subjected to hydrocracking to obtain hydrocracking products;

[0101] (6) The hydroisomers from step (4) and the hydrocracking products from step (5) are subjected to a second fractionation to obtain LPG II, naphtha II, aviation kerosene and cracking tail oil; wherein the cracking tail oil is returned to step (5) for hydrocracking reaction.

[0102] (7) One or more of LPGⅠ, naphthaⅠ, LPGⅡ, and naphthaⅡ are treated in one or more of the following ways: reforming, aromatization; and then the reformed product and / or aromatized product are alkylated together with at least a portion of the stripped light component and at least a portion of the stripped intermediate component to obtain an alkylated product, and returned to step (2) for hydrorefining.

[0103] 2. According to the method described in paragraph 1, wherein in step (7), at least a portion of LPG I, at least a portion of naphtha I, at least a portion of LPG II and / or at least a portion of naphtha II are aromatized; or, at least a portion of naphtha I and / or at least a portion of naphtha II are reformed.

[0104] 3. According to the method described in paragraph 2, wherein in step (7), all or part of LPGⅠ, all or part of naphthaⅠ, and all of LPGⅡ and / or all of naphthaⅡ are aromatized; or, all or part of naphthaⅠ and / or all of naphthaⅡ are reformed.

[0105] 4. The method according to any one of paragraphs 1-3, wherein in step (7), all or part of LPGⅠ, all or part of naphthaⅠ, and all of LPGⅡ and / or all of naphthaⅡ are aromatized, and then the aromatized product is alkylated together with stripped light component and stripped intermediate component to obtain alkylated product, and returned to step (2) for hydrorefining.

[0106] 5. The method according to any one of paragraphs 1-3, wherein in step (7), all or part of naphtha I and all of naphtha II are reformed, and the reformed product is then alkylated together with stripped light components and stripped intermediate components to obtain an alkylated product, which is then returned to step (2) for hydrorefining.

[0107] 6. The method according to any one of paragraphs 1-3, wherein in step (7), all or part of LPGⅠ and all of LPGⅡ are aromatized, and all or part of naphthaⅠ and / or all of naphthaⅡ are reformed, and the reformed product and / or aromatized product are then alkylated together with stripped light component and stripped intermediate component to obtain alkylated product, and returned to step (2) for hydrorefining.

[0108] 7. The method according to any one of paragraphs 1-3, wherein step (7) is selected from one or more of the following:

[0109] a. At least a portion of naphtha I and at least a portion of naphtha II are reformed to obtain reformed products; then at least a portion of stripped light components, at least a portion of stripped intermediate components and reformed products are alkylated together to obtain alkylated products, and returned to step (2) for hydrorefining.

[0110] b. At least a portion of LPG I, at least a portion of naphtha I, at least a portion of LPG II, and at least a portion of naphtha II are subjected to an aromatization reaction to obtain an aromatized product; then at least a portion of the stripped light component, at least a portion of the stripped intermediate component, and the aromatized product are subjected to an alkylation reaction to obtain an alkylated product, and returned to step (2) for hydrorefining; or

[0111] c. At least a portion of LPG I and at least a portion of LPG II are subjected to aromatization to obtain an aromatized product; at least a portion of naphtha I and at least a portion of naphtha II are subjected to reforming to obtain a reformed product; at least a portion of the stripped light component, at least a portion of the stripped intermediate component, the aromatized product and the reformed product are subjected to alkylation to obtain an alkylated product, and then returned to step (2) for hydrorefining.

[0112] 8. The method according to any one of paragraphs 1-3, wherein step (7) is selected from one or more of the following:

[0113] All or part of naphtha I and all of naphtha II are reformed to obtain reformed products; then stripped light components, stripped intermediate components and reformed products are alkylated together to obtain alkylated products, and returned to step (2) for hydrorefining.

[0114] All or part of LPG I, all or part of naphtha I, all of LPG II, and all of naphtha II are subjected to aromatization to obtain aromatized products; then, the stripped light component, the stripped intermediate component, and the aromatized products are subjected to alkylation to obtain alkylated products, which are then returned to step (2) for hydrorefining; or

[0115] All or part of LPGⅠ and all of LPGⅡ are subjected to aromatization reaction to obtain aromatized products; all or part of naphthaⅠ and all of naphthaⅡ are subjected to reforming reaction to obtain reformed products; stripped light components, stripped intermediate components, aromatized products and reformed products are subjected to alkylation reaction to obtain alkylated products, and then returned to step (2) for hydrogenation purification.

[0116] 9. The method according to any one of paragraphs 1-3, wherein in step (1), the stripping conditions are: top temperature 90℃-180℃, bottom temperature 220℃-300℃, pressure 0.01Mpa-0.06Mpa, and theoretical plate number 10-20.

[0117] 10. The method according to any one of paragraphs 1-3, wherein in step (2), the hydrorefining is carried out under the action of a hydrorefining catalyst.

[0118] 11. The method according to paragraph 10, wherein the hydrorefining catalyst comprises a support and an active metal supported on the support, wherein the support comprises alumina and / or silica; and the active metal comprises one or more of a noble metal, a Group VIB non-noble metal, or a Group VIII non-noble metal.

[0119] 12. The method according to paragraph 11, wherein the support is γ-Al2O3; or the active metal is one or more of Mo, W, Co and Ni.

[0120] 13. The method according to any one of paragraphs 1-3, wherein the hydrorefining reaction comprises one or more catalyst beds, each of the catalyst beds being packed with the same or different types of hydrorefining catalyst.

[0121] 14. The method according to paragraph 10, wherein a hydrogenation catalyst protectant is loaded when the hydrogenation reaction is carried out using a hydrogenation refining catalyst.

[0122] 15. The method according to any one of paragraphs 1-3, wherein, in step (2), the conditions for hydrorefining are: reaction temperature of 150℃-400℃; reaction pressure of 2-12 MPa; hydrogen-to-oil volume ratio of (300-1500):1; and volume hourly space velocity of 0.1-5 h⁻¹. -1 .

[0123] 16. The method according to any one of paragraphs 1-3, wherein in step (3), the conditions for the first fractionation are: top temperature of 50℃-150℃, bottom temperature of 250℃-350℃, pressure of 0.01-0.15MPa, and theoretical number of plates of 20-30.

[0124] 17. The method according to paragraph 16, wherein in step (4), the hydroisomerization reaction is carried out in the presence of a hydroisomerization catalyst; wherein the hydroisomerization catalyst comprises a support and an active metal supported on the support.

[0125] 18. The method according to paragraph 17, wherein the support comprises one or more of Beta, USY, ZSM-22, SAPO-11, ZSM-23, ZSM-35 molecular sieve supports or amorphous silicon; and the active metal comprises one or more of Group VIB non-noble metals and Group VIII metals.

[0126] 19. The method according to paragraph 18, wherein the active metal is one or more of Ni, Co, Mo, and W.

[0127] 20. The method according to any one of paragraphs 1-3, wherein, in step (4), the conditions for the hydroisomerization are: a reaction temperature of 260℃-380℃; a reaction pressure of 1-8 MPa; a hydrogen-to-oil volume ratio of (300-1000):1; and a volume hourly space velocity of 0.1-5 h⁻¹. -1 .

[0128] 21. The method according to any one of paragraphs 1-3, wherein in step (5), the hydrocracking is carried out in the presence of a hydrocracking catalyst, wherein the hydrocracking catalyst comprises a support and an active metal supported on the support.

[0129] 22. The method according to paragraph 21, wherein the support comprises one or more of alumina, silica, amorphous silica-alumina, Y, USY, Beta, MCM-41, Y-Beta composite molecular sieves, and amorphous alumina and / or silica-alumina; and the active metal comprises one or more of Group VIB non-precious metals and / or Group VIII non-precious metals.

[0130] 23. The method according to paragraph 22, wherein the active metal is one or more of Ni, Co, Mo, and W.

[0131] 21. The method according to any one of paragraphs 1-3, wherein, in step (5), the conditions for hydrocracking are: a reaction temperature of 260℃-380℃; a reaction pressure of 1-8 MPa; a hydrogen-to-oil volume ratio of (300-1000):1; and a volume hourly space velocity of 0.1-5 h⁻¹. -1 .

[0132] 22. The method according to any one of paragraphs 1-3, wherein in step (6), the conditions for the second fractionation are: top temperature 30℃-150℃; bottom temperature 250℃-350℃; pressure 0.01-0.15MPa; theoretical plate number 20-30.

[0133] 23. The method according to any one of paragraphs 1-3, wherein, in step (7), all or part of the LPGⅠ is aromatized, wherein the LPGⅠ undergoing aromatization accounts for 5%-100% of the total LPGⅠ.

[0134] 24. The method according to any one of paragraphs 1-3, wherein, in step (7), all or part of the LPG ⅠI is aromatized, wherein the proportion of LPG ⅠI undergoing aromatization is 5%-100% of the total LPG ⅠI.

[0135] 25. The method according to any one of paragraphs 1-3, wherein, in step (7), all or part of the naphtha I is subjected to an aromatization reaction or a reforming reaction, wherein the naphtha I subjected to the aromatization reaction or reforming reaction accounts for 10%-100% of the total naphtha I.

[0136] 26. The method according to any one of paragraphs 1-3, wherein, in step (7), all or part of the naphtha Ⅱ is subjected to an aromatization reaction or a reforming reaction, specifically the naphtha Ⅱ subjected to the aromatization reaction or reforming reaction accounts for 10%-100% of the total naphtha Ⅰ.

[0137] 27. The method according to any one of paragraphs 1-3, wherein in step (7), the reforming reaction is carried out under the action of a reforming catalyst, wherein the reforming catalyst comprises a bifunctional reforming catalyst and a non-acidic reforming catalyst.

[0138] 28. The method according to paragraph 27, wherein the bifunctional reforming catalyst is selected from Pt-Sn / Al2O3-Cl - Pt-Re / Al2O3-Cl - One or more of them.

[0139] 29. The method according to paragraph 27, wherein the non-acidic reforming catalyst is selected from one or more of Pt / KL, Pt / Kβ, Pt / KY, Pt-Sn / KL, and Pt-Re / KL.

[0140] 30. The method according to any one of paragraphs 1-3, wherein, in step (7), the conditions for the reforming reaction are: a reaction temperature of 250℃-550℃; a reaction pressure of 0.1-4MPa; a hydrogen-to-oil volume ratio of (300-1000):1; and a volume hourly space velocity of 0.1-5h. -1 .

[0141] 31. The method according to any one of paragraphs 1-3, wherein in step (7), the aromatization reaction is carried out under the action of an aromatization catalyst, wherein the aromatization catalyst includes Zn and Ga modified ZSM-5 and ZSM-11.

[0142] 32. The method according to any one of paragraphs 1-3, wherein, in step (7), the conditions for the aromatization reaction are: a reaction temperature of 250℃-550℃; a reaction pressure of 0.1-4MPa; and a volume hourly space velocity of 0.1-5h. -1 .

[0143] 33. The method according to any one of paragraphs 1-3, wherein in step (7), the alkylation reaction is carried out in the presence of an alkylation catalyst, wherein the alkylation catalyst comprises one or more of a liquid acid, a solid acid, a molecular sieve, and a heteropoly acid.

[0144] 34. The method according to paragraph 33, wherein the alkylation catalyst is one or more of molecular sieves and solid superacids.

[0145] 35. The method according to paragraph 33, wherein the alkylation catalyst is one or more selected from H2SO4, AlCl3, Beta, ZSM-5, MOR, USY, MCM-22, solid phosphoric acid, and solid superacid.

[0146] 36. The method according to any one of paragraphs 1-3, wherein, in step (7), the conditions for the alkylation reaction are: a reaction temperature of 100°C-350°C; a reaction pressure of 1-8 MPa; and a volume hourly space velocity of 0.1-5 h⁻¹. -1 .

[0147] 37. A system for preparing high-quality jet fuel from Fischer-Tropsch synthesis intermediates, the system comprising: a stripping unit, an aromatization unit, a reforming unit, an alkylation unit, a hydrorefining unit, a hydroisomerization unit, a hydrocracking unit, and first and second fractionation units.

[0148] The invention is further illustrated by the following examples, but the invention is not limited thereto.

[0149] Example

[0150] Unless otherwise stated, the reagents, materials and apparatus involved in the following examples are all commercially available in the art; the routine operations involved in the following examples can be found in patents, patent applications and publications disclosed in the art (e.g., He Yongde, ed., Modern Coal Chemical Technology Handbook, Chemical Industry Press, 2003, but not limited thereto).

[0151] Example 1

[0152] This embodiment adopts Figure 1 The process shown is as follows, specifically:

[0153] The Fischer-Tropsch synthesis unit products were stripped under the following conditions: top temperature 150℃, bottom temperature 270℃, pressure 0.03MPa, and 14 theoretical plates. The stripped products were separated into light stripped components, intermediate stripped components, and heavy stripped components. The heavy stripped components were then subjected to hydrorefining with a Ni-W / γ-Al₂O₃ catalyst at 260℃, pressure 10MPa, and space velocity 1.0 h⁻¹. -1 The hydrogen-to-oil ratio was 600, and a hydrorefining reaction was carried out to obtain the hydrorefined product. The hydrorefined product was subjected to a first fractionation at a top temperature of 138℃, a bottom temperature of 295℃, a pressure of 0.11MPa, and 25 theoretical plates to obtain LPG I, naphtha I, a first intermediate component, and a first heavy component. The first intermediate component was then subjected to hydroisomerization with a Ni-W / ZSM-22 catalyst at a temperature of 350℃, a pressure of 6MPa, and a space velocity of 2h⁻¹. -1The hydrogen-to-oil ratio was 600, and a hydroisomerization reaction was carried out to obtain the hydroisomerized product. The first heavy component was then subjected to hydrocracking with a Ni-W / USY catalyst at a temperature of 345℃, a pressure of 6 MPa, and a space velocity of 1.5 h⁻¹. -1 Hydrocracking reaction is carried out under a hydrogen-to-oil ratio of 600 to obtain hydrocracking products. The hydroisomers and hydrocracking products are then subjected to a second fractionation at a top temperature of 137°C, a bottom temperature of 301°C, a pressure of 0.12 MPa, and 26 theoretical plates to obtain LPG II, naphtha II, aviation kerosene, and cracking tail oil. All cracking tail oil is returned for hydrocracking.

[0154] 20% naphtha I and all of naphtha II were reacted with a Pt-Re / KL reforming catalyst at 480°C, 1 MPa, and a space velocity of 1.2 h⁻¹. -1 The reforming reaction was carried out under a hydrogen-to-oil ratio of 600 to obtain the reformed product; then, the stripped light component, stripped intermediate component, and reformed product were co-processed in the presence of MCM-22 molecular sieve catalyst at a temperature of 140℃, a pressure of 3MPa, and a space velocity of 2h. -1 The alkylation reaction was carried out under certain conditions to obtain the alkylated product, which was then returned for hydrogenation purification.

[0155] The product yields of each reaction unit in this embodiment are shown in Table 1, and the product properties are shown in Table 2.

[0156] Example 2

[0157] This embodiment adopts Figure 1 The process shown is as follows, specifically:

[0158] The Fischer-Tropsch synthesis unit products were stripped under the following conditions: top temperature 150℃, bottom temperature 270℃, pressure 0.03MPa, and 14 theoretical plates. The stripped products were separated into light stripped components, intermediate stripped components, and heavy stripped components. The heavy stripped components were then subjected to hydrorefining with a Ni-W / γ-Al₂O₃ catalyst at 260℃, pressure 10MPa, and space velocity 1.0 h⁻¹. -1 Hydrorefining reaction was carried out under a hydrogen-to-oil ratio of 600 to obtain the hydrorefined product. The hydrorefined product was subjected to a first fractionation at a top temperature of 138℃, a bottom temperature of 295℃, a pressure of 0.11MPa, and 25 theoretical plates to obtain LPG I, naphtha I, a first intermediate component, and a first heavy component. The first intermediate component was then subjected to hydroisomerization with a Ni-W / ZSM-22 catalyst at a temperature of 350℃, a pressure of 6.0MPa, and a space velocity of 2h⁻¹. -1The first heavy component underwent a hydroisomerization reaction at a hydrogen-to-oil ratio of 600 to obtain the hydroisomerized product. The first heavy component was then subjected to hydrocracking with a Ni-W / USY molecular sieve catalyst at a temperature of 345℃, a pressure of 6 MPa, and a space velocity of 1.5 h⁻¹. -1 Hydrocracking reaction is carried out under a hydrogen-to-oil ratio of 600 to obtain hydrocracking products. The hydroisomers and hydrocracking products are then subjected to a second fractionation at a top temperature of 137°C, a bottom temperature of 301°C, a pressure of 0.12 MPa, and 26 theoretical plates to obtain LPG II, naphtha II, aviation kerosene, and cracking tail oil. All cracking tail oil is returned for hydrocracking.

[0159] 90% of naphtha I and all of naphtha II were reformed using a Pt-Re / KL catalyst at 480°C, 1 MPa, and a space velocity of 1.2 h⁻¹. -1 The reforming reaction was carried out under a hydrogen-to-oil ratio of 600 to obtain the reformed product; then, the stripped light component, stripped intermediate component, and reformed product were co-existing in the presence of an MCM-22 molecular sieve catalyst, and the reaction was carried out at a temperature of 140℃, a pressure of 3MPa, and a space velocity of 2h. -1 The alkylation reaction was carried out under certain conditions to obtain the alkylated product, which was then returned for hydrogenation purification.

[0160] The product yields of each reaction unit in this embodiment are shown in Table 1, and the product properties are shown in Table 2.

[0161] Example 3

[0162] This embodiment adopts Figure 2 The process shown is as follows, specifically:

[0163] The Fischer-Tropsch synthesis unit products were stripped under the following conditions: top temperature 150℃, bottom temperature 270℃, pressure 0.03MPa, and 14 theoretical plates. The stripped products were separated into light stripped components, intermediate stripped components, and heavy stripped components. The heavy stripped components were then subjected to hydrorefining with a Ni-W / γ-Al₂O₃ catalyst at 260℃, pressure 10MPa, and space velocity 1.0 h⁻¹. -1 The hydrogen-to-oil ratio is 600, and a hydrorefining reaction is carried out to obtain the hydrorefined product. The hydrorefined product is then subjected to a first fractionation at a top temperature of 138°C, a bottom temperature of 301°C, a pressure of 0.11 MPa, and 25 theoretical plates to obtain LPG I, naphtha I, a first intermediate component, and a first heavy component. The first intermediate component is then subjected to hydroisomerization with a Ni-W / ZSM-22 catalyst at a temperature of 350°C, a pressure of 6 MPa, and a space velocity of 2 h⁻¹. -1The first heavy component underwent a hydroisomerization reaction under a hydrogen-to-oil ratio of 600 to obtain the hydroisomerized product. The first heavy component was then subjected to hydrocracking with a Ni-W / USY catalyst at a temperature of 345℃, a pressure of 6 MPa, and a space velocity of 1.5 h⁻¹. -1 Hydrocracking reaction is carried out under a hydrogen-to-oil ratio of 600 to obtain hydrocracking products. The hydroisomers and hydrocracking products are then subjected to a second fractionation at a top temperature of 137°C, a bottom temperature of 301°C, a pressure of 0.12 MPa, and 26 theoretical plates to obtain LPG II, naphtha II, aviation kerosene, and cracking tail oil. All cracking tail oil is returned for hydrocracking.

[0164] 10% LPG I, 20% naphtha I, and all of LPG II and naphtha II were reacted in the presence of a Ga / ZSM-5 catalyst at a temperature of 490℃, a pressure of 0.3 MPa, and a space velocity of 0.5 h⁻¹. -1 Under certain conditions, an aromatization reaction was carried out to obtain the aromatized product; then, the stripped light component, the stripped intermediate component, and the aromatized product were jointly subjected to an aromatization reaction in the presence of an MCM-22 molecular sieve catalyst at a temperature of 140℃, a pressure of 3MPa, and a space velocity of 2h. -1 The alkylation reaction was carried out under certain conditions to obtain the alkylated product, which was then returned for hydrogenation purification.

[0165] The product yields of each reaction unit in this embodiment are shown in Table 1, and the product properties are shown in Table 2.

[0166] Example 4

[0167] This embodiment adopts Figure 3 The process shown is as follows, specifically:

[0168] The Fischer-Tropsch synthesis unit products were stripped under the following conditions: top temperature 150℃, bottom temperature 270℃, pressure 0.03MPa, and 14 theoretical plates. The stripped products were separated into light stripped components, intermediate stripped components, and heavy stripped components. The heavy stripped components were then subjected to hydrorefining with a Ni-W / γ-Al₂O₃ catalyst at 260℃, pressure 10MPa, and space velocity 1.0 h⁻¹. -1 The hydrogen-to-oil ratio was 600, and a hydrorefining reaction was carried out to obtain the hydrorefined product. The hydrorefined product was subjected to a first fractionation at a top temperature of 138℃, a bottom temperature of 295℃, a pressure of 0.11MPa, and 25 theoretical plates to obtain LPG I, naphtha I, a first intermediate component, and a first heavy component. The first intermediate component was then subjected to hydroisomerization with a Ni-W / ZSM-22 catalyst at a temperature of 350℃, a pressure of 6MPa, and a space velocity of 2h⁻¹. -1The hydrogen-to-oil ratio was 600, and a hydroisomerization reaction was carried out to obtain the hydroisomerized product. The first heavy component was then subjected to hydrocracking with a Ni-W / USY catalyst at a temperature of 345℃, a pressure of 6 MPa, and a space velocity of 1.5 h⁻¹. -1 Hydrocracking reaction is carried out under a hydrogen-to-oil ratio of 600 to obtain hydrocracking products. The hydroisomers and hydrocracking products are then subjected to a second fractionation at a top temperature of 137°C, a bottom temperature of 301°C, a pressure of 0.12 MPa, and 26 theoretical plates to obtain LPG II, naphtha II, aviation kerosene, and cracking tail oil. All cracking tail oil is returned for hydrocracking.

[0169] 10% LPGⅠ and all LPGⅡ were reacted in the presence of Ga / ZSM-5 catalyst at a temperature of 535℃, a pressure of 0.3 MPa, and a space velocity of 0.5 h⁻¹. -1 The aromatization reaction was carried out under the following conditions to obtain the aromatized product; 20% naphtha I and all of naphtha II were reacted in the presence of a Pt-Re / KL reforming catalyst at a temperature of 480℃, a pressure of 1 MPa, and a space velocity of 1.2 h⁻¹. -1 A reforming reaction was carried out under a hydrogen-to-oil ratio of 600 to obtain the reformed product. Then, the stripped light component, stripped intermediate component, reformed product, and aromatized product were subjected to a reaction in the presence of an MCM-22 molecular sieve catalyst at a temperature of 140℃, a pressure of 3MPa, and a space velocity of 2h. -1 The alkylation reaction was carried out under certain conditions to obtain the alkylated product, which was then returned for hydrogenation purification.

[0170] The product yields of each reaction unit in this embodiment are shown in Table 1, and the product properties are shown in Table 2.

[0171] Comparative Example 1

[0172] This comparative example adopts Figure 1 The process shown is as follows, specifically:

[0173] The Fischer-Tropsch synthesis unit product was stripped under conditions of 150°C at the top, 270°C at the bottom, 0.03 MPa at a pressure of 14 theoretical plates, and separated into three fractions: LPG, C5-C8, and C9+. All three fractions were then fed into a hydrorefining unit for hydrorefining. The refined product was then fractionated in a distillation column to obtain LPG, naphtha, C9-C16, and C17+ fractions. The LPG and naphtha fractions were sent to the finished product tank area. The C9-C16 fraction was fed into a hydroisomerization unit under conditions of Pt-Pd / ZSM-22 catalyst, 335°C, 6 MPa at a pressure of 2 h⁻¹. -1Isomerization was carried out under a hydrogen-to-oil ratio of 600; the C17+ fraction was fed into a hydrocracking unit and subjected to hydrocracking at 345°C, 6 MPa, and 1.5 h⁻¹ in the presence of a Pt / USY catalyst. -1 Hydrocracking reaction is carried out under a hydrogen-to-oil ratio of 600. The products of the hydroisomerization unit and the hydrocracking unit are fractionated into LPG / naphtha fraction, jet fuel fraction and cracking tail oil after passing through a fractionation tower. The LPG / naphtha fraction and jet fuel fraction are sent to the finished product tank area as products, while the cracking tail oil is recycled back into the hydrocracking unit through a circulation system.

[0174] The product yields of each reaction unit in this comparative example are shown in Table 1, and the product properties are shown in Table 2.

[0175] Comparative Example 2

[0176] This comparative example adopts Figure 1 The process shown is as follows, specifically:

[0177] The Fischer-Tropsch synthesis unit product was stripped under conditions of 150°C top temperature, 270°C bottom temperature, 0.03 MPa pressure, and 14 theoretical plates. The stripping column separated the product into three fractions: LPG, C5-C8, and C9+. All three fractions were then fed into a hydrorefining unit for further hydrorefining. The refined product was then fractionated in a distillation column to obtain LPG, naphtha, C9-C16, and C17+ fractions. The LPG and naphtha fractions were sent to the finished product tank area. The C9-C16 fraction was fed into a hydroisomerization unit and subjected to hydroisomerization at 350°C, 6 MPa pressure, and 2 h⁻¹ space velocity in the presence of a Ni-W / ZSM-22 catalyst. -1 Isomerization was carried out under a hydrogen-to-oil ratio of 600; the C17+ fraction was fed into a hydrocracking unit and subjected to hydrocracking in the presence of a Ni-W / USY catalyst at a temperature of 345°C, a pressure of 6 MPa, and a space velocity of 1.5 h⁻¹. -1 Hydrocracking reaction is carried out under a hydrogen-to-oil ratio of 600. The products of the hydroisomerization unit and the hydrocracking unit are fractionated into LPG / naphtha fraction, jet fuel fraction and cracking tail oil after passing through a fractionation tower. The LPG / naphtha fraction and jet fuel fraction are sent to the finished product tank area as products, while the cracking tail oil is recycled back into the hydrocracking unit through a circulation system.

[0178] The product yields of each reaction unit in this comparative example are shown in Table 1, and the product properties are shown in Table 2.

[0179] The above embodiments more clearly illustrate the advantages of the method of the present invention and the level that the product obtained by the present invention can achieve. According to the method of the present invention, the light oil components of Fischer-Tropsch synthesis are fully utilized, and the yield and quality of aviation kerosene components can be flexibly adjusted. The produced aviation kerosene components have the characteristics of low sulfur content and high calorific value, and can be used directly as aviation kerosene or as an excellent blending component for petroleum-based aviation kerosene. It has a positive effect on reducing emissions and improving combustibility.

[0180] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

[0181]

Claims

1. A method for preparing aviation kerosene from Fischer-Tropsch synthesis intermediates, the method comprising: (1) Stripping the Fischer-Tropsch synthesis intermediates to obtain stripped light components, stripped intermediate components and stripped heavy components; (2) The stripped heavy components from step (1) are subjected to hydrorefining to obtain the hydrorefined product; (3) The hydrorefined product from step (2) is subjected to a first fractionation to obtain LPG I, naphtha I, a first intermediate component and a first heavy component; (4) The first intermediate component from step (3) is subjected to hydroisomerization to obtain the hydroisomerized product; (5) The first heavy component from step (3) is subjected to hydrocracking to obtain hydrocracking products; (6) The hydroisomers from step (4) and the hydrocracking products from step (5) are subjected to a second fractionation to obtain LPG II, naphtha II, aviation kerosene and cracking tail oil; wherein the cracking tail oil is returned to step (5) for hydrocracking reaction. (7) One or more of LPG I, naphtha I, LPG II, and naphtha II are treated in one or more of the following ways: reforming, aromatization; and then the reformed product and / or aromatized product are alkylated together with at least a portion of the stripped light component and at least a portion of the stripped intermediate component to obtain an alkylated product, and returned to step (2) for hydrorefining.

2. The method according to claim 1, wherein, In step (7), at least a portion of LPG I, at least a portion of naphtha I, at least a portion of LPG II and / or at least a portion of naphtha II are aromatized; Alternatively, at least a portion of naphtha I and / or at least a portion of naphtha II may be reformed.

3. The method according to claim 2, wherein, In step (7), all or part of LPG I, all or part of naphtha I, and all of LPG II and / or all of naphtha II are aromatized; Alternatively, all or part of naphtha I and / or all of naphtha II may be reformed.

4. The method according to any one of claims 1-3, wherein, In step (7), all or part of LPG I, all or part of naphtha I, and all of LPG II and / or all of naphtha II are aromatized, and then the aromatized product is alkylated together with the stripped light component and the stripped intermediate component to obtain the alkylated product, and then returned to step (2) for hydrorefining.

5. The method according to any one of claims 1-3, wherein, In step (7), all or part of naphtha I and all of naphtha II are reformed, and then the reformed product is alkylated together with stripped light components and stripped intermediate components to obtain alkylated products, which are then returned to step (2) for hydrorefining.

6. The method according to any one of claims 1-3, wherein, In step (7), all or part of LPG I and all of LPG II are aromatized, and all or part of naphtha I and / or all of naphtha II are reformed. The reformed product and / or aromatized product are then alkylated together with stripped light components and stripped intermediate components to obtain alkylated products, which are then returned to step (2) for hydrorefining.

7. The method according to any one of claims 1-3, wherein, Step (7) is selected from one or more of the following: a. At least a portion of naphtha I and at least a portion of naphtha II are reformed to obtain reformed products; then at least a portion of stripped light components, at least a portion of stripped intermediate components and reformed products are alkylated together to obtain alkylated products, and returned to step (2) for hydrorefining. b. At least a portion of LPG I, at least a portion of naphtha I, at least a portion of LPG II, and at least a portion of naphtha II are subjected to an aromatization reaction to obtain an aromatized product; Then, at least a portion of the stripped light component, at least a portion of the stripped intermediate component, and the aromatization product are subjected to an alkylation reaction to obtain an alkylated product, which is then returned to step (2) for hydrogenation purification. or c. At least a portion of LPG I and at least a portion of LPG II are subjected to an aromatization reaction to obtain an aromatized product; At least a portion of naphtha I and at least a portion of naphtha II are subjected to a reforming reaction to obtain a reformed product; At least a portion of the stripped light component, at least a portion of the stripped intermediate component, the aromatization product and the reforming product are subjected to an alkylation reaction to obtain an alkylated product, which is then returned to step (2) for hydrogenation purification.

8. The method according to any one of claims 1-3, wherein, Step (7) is selected from one or more of the following: All or part of naphtha I and all of naphtha II are reformed to obtain reformed products; then stripped light components, stripped intermediate components and reformed products are alkylated together to obtain alkylated products, and returned to step (2) for hydrorefining. All or part of LPG I, all or part of naphtha I, all of LPG II, and all of naphtha II are subjected to aromatization to obtain aromatized products; then the stripped light components, stripped intermediate components, and aromatized products are subjected to alkylation to obtain alkylated products, and returned to step (2) for hydrorefining. or Aromatization of all or part of LPG I and all of LPG II yields aromatized products; All or part of naphtha I and all of naphtha II are reformed to obtain reformed products; stripped light components, stripped intermediate components, aromatized products and reformed products are alkylated together to obtain alkylated products, and then returned to step (2) for hydrorefining.

9. The method according to any one of claims 1-3, wherein, In step (1), the stripping conditions are: top temperature 90℃-180℃, bottom temperature 220℃-300℃, pressure 0.01Mpa-0.06Mpa, and theoretical number of trays 10-20.

10. The method according to any one of claims 1-3, wherein, In step (2), the hydrorefining is carried out under the action of a hydrorefining catalyst.

11. The method according to claim 10, wherein, The hydrorefining catalyst comprises a support and an active metal supported on the support, wherein the support comprises alumina and / or silica; and the active metal comprises one or more of a noble metal, a Group VIB non-noble metal, or a Group VIII non-noble metal.

12. The method according to claim 11, wherein, The support is γ-Al2O3; or the active metal is one or more of Mo, W, Co and Ni.

13. The method according to any one of claims 1-3, wherein, The hydrorefining reaction includes one or more catalyst beds, each of which is filled with the same or different types of hydrorefining catalyst.

14. The method of claim 10, wherein, When using a hydrorefining catalyst for a hydrorefining reaction, a hydrorefining catalyst protectant is loaded.

15. The method according to any one of claims 1-3, wherein, In step (2), the conditions of the hydrofining are as follows: reaction temperature is 150-400℃; reaction pressure is 2-12 MPa; hydrogen / oil volume ratio is (300-1500):1; volume space velocity is 0.1-5 h-1. -1 .

16. The method according to any one of claims 1-3, wherein, In step (3), the conditions for the first fractionation are: top temperature of 50℃-150℃, bottom temperature of 250℃-350℃, pressure of 0.01-0.15MPaG, and theoretical number of plates of 20-30.

17. The method according to claim 16, wherein, In step (4), the hydroisomerization reaction is carried out in the presence of a hydroisomerization catalyst; wherein the hydroisomerization catalyst comprises a support and an active metal supported on the support.

18. The method according to claim 17, wherein, The carrier includes one or more of Beta, USY, ZSM-22, SAPO-11, ZSM-23, ZSM-35 molecular sieve carriers or amorphous silicon; the active metal includes one or more of Group VIB non-noble metals and Group VIII metals.

19. The method according to claim 18, wherein, The active metal is one or more of Ni, Co, Mo, and W.

20. The method according to any one of claims 1-3, wherein, In step (4), the conditions for the hydroisomerization are: reaction temperature of 260℃-380℃; reaction pressure of 1-8 MPa; hydrogen-to-oil volume ratio of (300-1000):1; and volume hourly space velocity of 0.1-5 h⁻¹. -1 .

21. The method according to any one of claims 1-3, wherein, In step (5), the hydrocracking is carried out in the presence of a hydrocracking catalyst, wherein the hydrocracking catalyst comprises a support and an active metal supported on the support.

22. The method according to claim 21, wherein, The carrier includes one or more of alumina, silica, amorphous silica-alumina, Y, USY, Beta, MCM-41, and Y-Beta composite molecular sieves; the active metal includes one or more of Group VIB non-precious metals and / or Group VIII non-precious metals.

23. The method according to claim 21, wherein, The carrier is selected from amorphous alumina and / or amorphous aluminum silicate.

24. The method according to claim 22, wherein, The active metal is one or more of Ni, Co, Mo, and W.

25. The method according to any one of claims 1-3, wherein, In step (5), the hydrocracking conditions are as follows: reaction temperature 260℃-380℃; reaction pressure 1-8 MPa; hydrogen-to-oil volume ratio (300-1000):1; volume hourly space velocity (VHSV) 0.1-5 h⁻¹. -1 .

26. The method according to any one of claims 1-3, wherein, In step (6), the conditions for the second fractionation are: top temperature 30℃-150℃; bottom temperature 250℃-350℃; pressure 0.01-0.15MpaG; theoretical number of plates 20-30.

27. The method according to any one of claims 1-3, wherein, In step (7), all or part of LPG I is aromatized, wherein the proportion of LPG I undergoing aromatization is 5%-100% of the total LPG I.

28. The method according to any one of claims 1-3, wherein, In step (7), all or part of LPG Ⅱ is aromatized, wherein the proportion of LPG Ⅱ undergoing aromatization is 5%-100% of the total LPG Ⅱ.

29. The method according to any one of claims 1-3, wherein, In step (7), all or part of the naphtha I is subjected to aromatization or reforming reaction, wherein the naphtha I subjected to aromatization or reforming reaction accounts for 10%-100% of the total naphtha I.

30. The method according to any one of claims 1-3, wherein, In step (7), all or part of the naphtha Ⅱ is subjected to aromatization or reforming reaction, and the specific proportion of naphtha Ⅱ subjected to aromatization or reforming reaction to the total naphtha Ⅰ is 10%-100%.

31. The method according to any one of claims 1-3, wherein, In step (7), the reforming reaction is carried out under the action of a reforming catalyst, wherein the reforming catalyst includes a bifunctional reforming catalyst and a non-acidic reforming catalyst.

32. The method according to claim 31, wherein, The bifunctional reforming catalyst is selected from Pt-Sn / Al2O3-Cl - Pt-Re / Al2O3-Cl - One or more of them.

33. The method according to claim 31, wherein, The non-acidic reforming catalyst is selected from one or more of Pt / KL, Pt / Kβ, Pt / KY, Pt-Sn / KL, and Pt-Re / KL.

34. The method according to any one of claims 1-3, wherein, In step (7), the conditions for the reforming reaction are: reaction temperature of 250℃-550℃; reaction pressure of 0.1-4MPa; hydrogen-to-oil volume ratio of (300-1000):1; and volume hourly space velocity of 0.1-5h. -1 .

35. The method according to any one of claims 1-3, wherein, In step (7), the aromatization reaction is carried out under the action of an aromatization catalyst, wherein the aromatization catalyst includes Zn and / or Ga modified ZSM-5 and / or ZSM-11.

36. The method according to any one of claims 1-3, wherein, In step (7), the conditions for the aromatization reaction are: reaction temperature of 250℃-550℃; reaction pressure of 0.1-4MPa; and volume hourly space velocity of 0.1-5h. -1 .

37. The method according to claim 1, wherein, In step (7), the alkylation reaction is carried out under the action of an alkylation catalyst, wherein the alkylation catalyst includes one or more of liquid acid and solid acid.

38. The method according to claim 1, wherein, In step (7), the alkylation reaction is carried out under the action of an alkylation catalyst, wherein the alkylation catalyst includes one or more of molecular sieves and heteropoly acids.

39. The method according to claim 37 or 38, wherein, The alkylation catalyst is one or more of molecular sieves and solid superacids.

40. The method according to claim 37 or 38, wherein, The alkylation catalyst is one or more of H2SO4, AlCl3, Beta, ZSM-5, MOR, USY, MCM-22, solid phosphoric acid, and solid superacid.

41. The method according to any one of claims 1-3, wherein, In step (7), the alkylation reaction conditions are: reaction temperature of 100℃-350℃; reaction pressure of 1-8MPa; and volume hourly space velocity of 0.1-5h. -1 .

42. A system for preparing high-quality jet fuel from Fischer-Tropsch synthesis intermediates using the method of any one of claims 1-41, the system comprising: Stripping unit, aromatization unit, reforming unit, alkylation unit, hydrorefining unit, hydroisomerization unit, hydrocracking unit, and first and second fractionation units.

Images