Aviation kerosene and preparation method and preparation system thereof

Abstract

The invention discloses aviation kerosene as well as a preparation method and a preparation system thereof, and the preparation method of the aviation kerosene comprises the following steps: (1) distilling direct coal liquefaction oil to obtain a first light oil fraction, a first aviation kerosene fraction and a heavy oil fraction; (2) hydrocracking the heavy oil fraction to obtain a second light oil fraction and a second jet fuel fraction; (3) mixing the first light oil fraction and the second light oil fraction, and carrying out alkylation reaction and hydrogenation reaction to obtain a third aviation kerosene fraction; and (4) hydrofining the first aviation kerosene fraction, the second aviation kerosene fraction and the third aviation kerosene fraction to obtain aviation kerosene. The method provided by the invention realizes maximum production of aviation kerosene from the direct coal liquefaction oil, improves the yield of aviation kerosene, realizes high-valued utilization of the direct coal liquefaction oil and methanol, and reduces the production cost at the same time.

Description

Technical Field

[0001] The present invention relates to the field of coal chemical industry, and in particular to aviation kerosene and a preparation method and a preparation system thereof. Background Art

[0002] Liquid fuel is the power source of aircraft, and fuel energy determines flight performance. Conventional liquid fuel has low energy, which has become a bottleneck problem restricting the performance of existing aircraft and the development of new aircraft. The energy of fuel (energy = density * calorific value) depends on its molecular structure. Petroleum refined fuel is mainly chain structure and single ring structure with lower density and volume calorific value, while Fischer-Tropsch synthetic fuel has a higher chain structure content.

[0003] Coal direct liquefaction oil is rich in polycyclic aromatic hydrocarbons and has a unique molecular structure. It fully retains the high-density polycyclic structure unique to coal and is a high-quality raw material for preparing high-density, high heat sink, and high thermal stability high-performance fuels. The preparation of aerospace special fuels with coal direct liquefaction oil is of great significance to ensure the urgent demand for fuel for high-performance aircraft.

[0004] The preparation of aviation kerosene from direct coal liquefaction oil generally undergoes processes such as dephenolization, hydrogenation and decontamination, hydrogenation and saturation, and fraction cutting to obtain a cycloalkane mixture with a boiling range of 150 to 300°C. However, the yield of aviation kerosene from this route is low, the product performance is poor, and the economic efficiency needs to be improved. Summary of the invention

[0005] The present invention is based on the inventor's discovery and understanding of the following facts and problems: the current method for preparing aviation kerosene by direct liquefaction of coal oil has a low aviation kerosene fraction yield, poor product performance, and the economic efficiency needs to be improved.

[0006] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the embodiments of the present invention provide an aviation kerosene and a preparation method and system thereof, which realizes the maximum production of aviation kerosene from coal direct liquefaction oil, improves the yield of aviation kerosene, realizes the high-value utilization of coal direct liquefaction oil and methanol, and reduces the production cost.

[0007] An embodiment of the present invention provides a method for preparing aviation kerosene, comprising the following steps:

[0008] (1) distilling the coal direct liquefaction oil to obtain a first light oil fraction, a first aviation kerosene fraction and a heavy oil fraction;

[0009] (2) treating the heavy oil fraction by hydrocracking to obtain a second light oil fraction and a second jet fuel fraction;

[0010] (3) mixing the first light oil fraction and the second light oil fraction, and subjecting the mixture to an alkylation reaction and a hydrogenation reaction to obtain a third jet fuel fraction;

[0011] (4) The first jet fuel fraction, the second jet fuel fraction and the third jet fuel fraction are subjected to a hydrotreating treatment to obtain jet fuel.

[0012] The advantages and technical effects brought by the preparation method of aviation kerosene of the embodiment of the present invention are as follows: the coal direct liquefaction oil is distilled and separated to obtain a first light oil fraction, a first aviation kerosene fraction and a heavy oil fraction. The heavy oil fraction is subjected to hydrocracking treatment to further obtain a light oil fraction and an aviation kerosene fraction, and the heavy oil fraction is converted into aviation kerosene to the maximum extent. The mixed light oil fraction is subjected to alkylation reaction and hydrogenation reaction at the same time, and the hydrodeoxygenation reaction is efficiently carried out under hydrogen conditions, so that the phenolic substances rich in the mixed light oil fraction are converted into aromatics or alkylbenzenes. Aromatics and alkylbenzenes are components of the target product aviation kerosene, which can maximize the production of aviation kerosene; at the same time, the mixed light oil fraction is converted into an aviation kerosene fraction through an alkylation carbonization reaction, thereby improving the utilization rate of coal direct liquefaction oil and increasing the yield of aviation kerosene components; the hydrogen environment is conducive to slowing down the carbon deposition rate of the catalyst during the alkylation process, extending the service life of the catalyst and thus reducing the catalyst cost. By mixing the jet fuel fractions and performing hydrofining treatment to remove heteroatoms such as S and N, high-quality and excellent performance jet fuel is produced. The preparation method of jet fuel maximizes the conversion of heavy oil fractions into jet fuel, and carbonizes the light oil fractions through alkylation to produce jet fuel, which can improve the conversion efficiency of direct coal liquefaction to prepare jet fuel, realize the maximum production of jet fuel from direct coal liquefaction, improve the yield and fuel performance of jet fuel, and the preparation method is simple and economical, realizing the high-value utilization of direct coal liquefaction while reducing production costs.

[0013] In some embodiments, the cutting temperature of the first light oil fraction or the second light oil fraction is independently 170-230°C;

[0014] And / or, the cutting temperature of the heavy oil fraction is 280-300°C.

[0015] In some embodiments, in step (2), the hydrocracking treatment uses a fixed bed reactor;

[0016] And / or, the reaction temperature of the hydrocracking treatment is 320-470°C, the reaction pressure is 8-19 MPa, and the volume space velocity of the heavy oil fraction is 0.2-2.0 h -1 , hydrogen to oil volume ratio is 500-2000;

[0017] And / or, the hydrocracking treatment uses a hydrocracking catalyst; the hydrocracking catalyst includes an active component and a carrier; the active component includes at least one of Group VIB and Group VIII metal elements; the weight content of the active component in the hydrocracking catalyst is 0.2% to 20% in terms of metal elements; the carrier includes at least one of an inorganic oxide or a molecular sieve.

[0018] In some embodiments, in step (3), the first light oil fraction and the second light oil fraction are mixed, and subjected to alkylation reaction and hydrogenation reaction with methanol and hydrogen to obtain a third jet fuel fraction;

[0019] And / or, the alkylation reaction and hydrogenation reaction adopt a fixed bed reactor;

[0020] And / or, the reaction temperature of the alkylation reaction and the hydrogenation reaction is 200-460°C, and the volume space velocity of the mixed light oil fraction is 5-15h -1 , the reaction pressure is 4-20MPa, and the hydrogen-to-oil volume ratio is 5-20.

[0021] In some embodiments, in step (3), the molar ratio of methanol to mixed light oil fraction is (0.5-2):3.

[0022] In some embodiments, in step (3), the hydrogenation reaction uses a hydrogenation catalyst; the hydrogenation catalyst includes an active component and a carrier; the active component of the hydrogenation catalyst includes Cu element; the weight content of the active component in the hydrogenation catalyst is 0.1 to 8% in terms of metal element.

[0023] In some embodiments, in step (3), the alkylation reaction uses an alkylation catalyst; the alkylation catalyst includes an active component and a carrier; the active component includes at least one of Mo and Ni elements; the weight content of the active component in the alkylation catalyst is 0.1% to 5% as a metal element; the carrier includes at least one of molecular sieves; the molecular sieve includes at least one of ZSM-11 or MCM-22.

[0024] In some embodiments, in step (4), the hydrofining treatment uses a fixed bed reactor;

[0025] And / or, the reaction temperature of the hydrofining treatment is 260-400°C, the reaction pressure is 6-17 MPa, and the volume space velocity of the mixed aviation kerosene fraction is 0.2-2.0 h -1 , hydrogen-to-oil ratio is 500-2000;

[0026] And / or, the hydrorefining treatment uses a hydrorefining catalyst; the hydrorefining catalyst includes an active component and a carrier; the active component includes at least one of VIB and VIII group metal elements; the weight content of the active component in the hydrorefining catalyst is 0.2% to 20% in terms of metal elements; the carrier includes at least one of an inorganic oxide or a molecular sieve.

[0027] The embodiment of the present invention provides an aviation kerosene, which is prepared by the method for preparing the aviation kerosene according to the embodiment of the present invention. In the embodiment of the present invention, the aviation kerosene has a high yield and excellent fuel performance, and the high-value utilization of direct coal liquefaction oil is achieved while reducing the production cost of the aviation kerosene.

[0028] An embodiment of the present invention provides a system for preparing aviation kerosene, comprising:

[0029] A distillation separation unit, wherein the distillation separation unit is provided with a coal direct liquefied oil inlet, a first light oil fraction outlet, a first aviation kerosene fraction outlet and a heavy oil fraction outlet;

[0030] A hydrocracking unit, wherein the hydrocracking unit is provided with a heavy oil fraction inlet, a second light oil fraction outlet and a second jet fuel fraction outlet, and the heavy oil fraction inlet is connected to the heavy oil fraction outlet;

[0031] An alkylation and hydrogenation unit, wherein the alkylation and hydrogenation unit is provided with a first light oil fraction inlet, a second light oil fraction inlet and a third jet fuel fraction outlet, wherein the first light oil fraction inlet is connected to the first light oil fraction outlet, and the second light oil fraction inlet is connected to the second light oil fraction outlet;

[0032] The hydrotreating unit is provided with a first jet fuel fraction inlet, a second jet fuel fraction inlet, a third jet fuel fraction inlet and a jet fuel outlet, wherein the first jet fuel fraction inlet is connected to the first jet fuel fraction outlet, the second jet fuel fraction inlet is connected to the second jet fuel fraction outlet, and the third jet fuel fraction inlet is connected to the third jet fuel fraction outlet.

[0033] In the embodiment of the present invention, the aviation kerosene preparation system is used to implement the aviation kerosene preparation method described in the embodiment of the present invention or to prepare the aviation kerosene described in the embodiment of the present invention. The system for producing aviation kerosene can improve the conversion efficiency of coal direct liquefaction oil to prepare aviation kerosene, achieve maximum production of aviation kerosene from coal direct liquefaction oil, improve aviation kerosene yield and fuel performance, achieve high-value utilization of coal direct liquefaction oil while reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of a system for preparing aviation kerosene according to an embodiment of the present invention.

[0035] Reference numerals:

[0036] Distillation separation unit 100, hydrocracking unit 200, alkylation and hydrogenation unit 300, hydrofining unit 400;

[0037] Coal direct liquefaction oil 1, first light oil fraction 2, first aviation kerosene fraction 3, heavy oil fraction 4, second light oil fraction 5, second aviation kerosene fraction 6, methanol 7, third aviation kerosene fraction 8, gas product 9, aviation kerosene 10. DETAILED DESCRIPTION

[0038] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0039] A method for preparing aviation kerosene according to an embodiment of the present invention comprises the following steps:

[0040] (1) distilling the coal direct liquefaction oil to obtain a first light oil fraction, a first aviation kerosene fraction and a heavy oil fraction;

[0041] (2) treating the heavy oil fraction by hydrocracking to obtain a second light oil fraction and a second jet fuel fraction;

[0042] (3) mixing the first light oil fraction and the second light oil fraction, and subjecting the mixture to an alkylation reaction and a hydrogenation reaction to obtain a third jet fuel fraction;

[0043] (4) The first jet fuel fraction, the second jet fuel fraction and the third jet fuel fraction are subjected to a hydrotreating treatment to obtain jet fuel.

[0044] The preparation method of aviation kerosene of the embodiment of the present invention is to distill and separate the direct coal liquefaction oil to obtain a first light oil fraction, a first aviation kerosene fraction and a heavy oil fraction. The heavy oil fraction is subjected to hydrocracking treatment to further obtain a light oil fraction and an aviation kerosene fraction, and the heavy oil fraction is converted into aviation kerosene to the maximum extent. The mixed light oil fraction is subjected to alkylation reaction and hydrogenation reaction at the same time, and the hydrodeoxygenation reaction is efficiently carried out under hydrogen conditions, so that the phenolic substances rich in the mixed light oil fraction are converted into aromatics or alkylbenzenes, which are the components of the target product aviation kerosene, and can maximize the production of aviation kerosene; at the same time, the mixed light oil fraction is converted into an aviation kerosene fraction through an alkylation carbonization reaction, thereby improving the utilization rate of direct coal liquefaction oil and increasing the yield of aviation kerosene components; the hydrogen environment is conducive to slowing down the carbon deposition rate of the catalyst during the alkylation process, extending the service life of the catalyst and thus reducing the catalyst cost. The aviation kerosene fraction is mixed and subjected to hydrorefining treatment to greatly remove heteroatoms such as S and N, and produce high-quality aviation kerosene with excellent performance. The preparation method of aviation kerosene maximizes the conversion of heavy oil fractions into aviation kerosene, and realizes carbon increase of light oil fractions through alkylation reaction to produce aviation kerosene, which can improve the conversion efficiency of preparing aviation kerosene from coal direct liquefaction oil, realizes the maximum production of aviation kerosene from coal direct liquefaction oil, and improves the yield and fuel performance of aviation kerosene. The preparation method is simple and economical, realizes the high-value utilization of coal direct liquefaction oil while reducing production costs.

[0045] In some embodiments, the cutting temperature of the first light oil fraction or the second light oil fraction is independently 170-230°C, that is, the light oil fraction is a fraction not higher than the cutting temperature of 170-230°C, specifically, the cutting temperature may be 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C;

[0046] And / or, the first jet fuel fraction, the second jet fuel fraction, the third jet fuel fraction, and the aviation kerosene are each independently a fraction having a cutting temperature of not less than 170-230°C and / or not more than 280-300°C, that is, a fraction having a cutting temperature of not less than the cutting temperature of the light oil fraction and / or not more than the cutting temperature of the heavy oil fraction; in a specific embodiment, the aviation kerosene can be a fraction having a temperature of 170-300°C;

[0047] And / or, the cutting temperature of the heavy oil fraction is 280-300°C, that is, the heavy oil fraction is a fraction with a cutting temperature not lower than 280-300°C, specifically, the cutting temperature can be 280°C, 285°C, 290°C, 295°C, 300°C.

[0048] In some embodiments, in step (2), the heavy oil fraction is subjected to hydrocracking treatment and gas-liquid separation to obtain hydrogen-rich gas and liquid oil products; the liquid oil products are distilled to obtain a second light oil fraction and a second jet fuel fraction.

[0049] In some embodiments, in step (2), the hydrocracking treatment uses a fixed bed reactor. Optionally, the hydrocracking treatment uses one fixed bed reactor.

[0050] In some embodiments, in step (2), the reaction temperature of the hydrocracking treatment is 320-470°C, specifically, for example, 320°C, 400°C, 445°C, 450°C, 455°C, 470°C; the reaction pressure is 8-19MPa, specifically, for example, 8MPa, 10MPa, 16MPa, 17MPa, 18MPa, 19MPa; the volume space velocity of the heavy oil fraction is 0.2-2.0h -1 , specifically, for example, 0.2h -1 , 0.8h -1 , 1.0h -1 , 1.5h -1 , 2.0h -1 ; The volume ratio of hydrogen to oil is 500-2000, specifically, for example, 500, 1000, 1100, 1200, 1500, 2000.

[0051] In some embodiments, in step (2), the hydrocracking treatment uses a hydrocracking catalyst; the hydrocracking catalyst includes an active component and a carrier; the active component includes at least one of a VIB and VIII group metal element;

[0052] Optionally, the active component includes at least one of Ni, Mo, Co, and W metal elements; optionally, the active component is a sulfide of the metal element; the weight content of the active component in the hydrocracking catalyst is 0.2% to 20% in terms of metal element, specifically, for example, 0.2%, 0.5%, 1%, 2%, 5%, 10%, 15%, 20%; the carrier includes at least one of an inorganic oxide or a molecular sieve; optionally, the inorganic oxide includes at least one of alumina and silicon oxide.

[0053] In the embodiment of the present invention, the heavy oil fraction is subjected to hydrocracking treatment to further obtain a light oil fraction and an aviation kerosene fraction, so as to achieve direct coal liquefaction to produce more aviation kerosene and improve the aviation kerosene yield. The method of the present invention has no particular restriction on the type of hydrocracking catalyst, as long as it can catalyze the hydrocracking reaction; there is no particular restriction on the preparation method of the hydrocracking catalyst, which can be prepared in a conventional manner in the art.

[0054] In some embodiments, in step (3), the first light oil fraction and the second light oil fraction are mixed, and subjected to alkylation reaction and hydrogenation reaction with methanol and hydrogen to obtain a third jet fuel fraction; preferably, the molar ratio of methanol to the mixed light oil fraction is (0.5-2):3, specifically, for example, 0.5:3, 1:3, 1.5:3, 2:3.

[0055] In the embodiment of the present invention, the alkylation reaction adopts a hydrogenation process, so that the mixed light oil fraction of the coal direct liquefaction oil undergoes an alkylation reaction with methanol to generate a jet fuel fraction, and the light oil fraction is carbonized to produce jet fuel through the alkylation reaction, which can improve the conversion efficiency of the coal direct liquefaction oil to prepare jet fuel, realize the maximum production of jet fuel from the coal direct liquefaction oil, improve the jet fuel yield and fuel performance, make full use of the abundant and low-priced methanol resources, and reduce the production cost while realizing the high-value utilization of methanol.

[0056] In some embodiments, in step (3), the first light oil fraction and the second light oil fraction are mixed, subjected to alkylation reaction and hydrogenation reaction with methanol and hydrogen, and then subjected to gas-liquid separation and fractionation to obtain the third jet fuel fraction.

[0057] In some embodiments, in step (3), the alkylation reaction adopts a hydrogenation process.

[0058] In some embodiments, in step (3), the alkylation reaction and hydrogenation reaction are carried out using a fixed bed reactor.

[0059] In some embodiments, in step (3), the reaction temperature of the alkylation reaction and the hydrogenation reaction is 200-460°C, specifically, for example, 200°C, 300°C, 420°C, 430°C, 435°C, 460°C; the volume space velocity of the mixed light oil fraction is 5-15h -1 , specifically, for example, 5h -1 , 8h -1 , 9h -1 , 10h -1 , 12h -1 , 15h -1 ; The reaction pressure is 4 to 20 MPa, specifically, for example, 4 MPa, 5 MPa, 6 MPa, 10 MPa, 15 MPa, 20 MPa; The hydrogen-to-oil volume ratio is 5-20, specifically, for example, 5, 6, 8, 10, 15, 20.

[0060] In some embodiments, in step (3), the hydrogenation reaction uses a hydrogenation catalyst; the hydrogenation catalyst includes an active component and a carrier; the active component of the hydrogenation catalyst includes Cu element;

[0061] Optionally, the active component is a sulfide of a metal element, specifically, a sulfide of the Cu element; the weight content of the active component in the hydrogenation catalyst is 0.1-8% in terms of the metal element, specifically, for example, 0.1%, 0.5%, 0.6%, 1%, 2%, 5%, 6%, 7%, 8%; the carrier includes at least one of an inorganic oxide or a molecular sieve; the inorganic oxide includes at least one of aluminum oxide and silicon oxide.

[0062] In the embodiment of the present invention, in the presence of a hydrogenation catalyst, the phenolic substances in the mixed light oil fraction are subjected to a hydrodeoxygenation reaction with hydrogen, thereby reducing the oxygen content in the raw material, obtaining aromatics and alkylbenzenes, and increasing the yield of the aviation kerosene component. The hydrogenation conditions and the hydrogenation catalyst containing Cu can efficiently carry out the hydrodeoxygenation reaction, convert the phenolic substances rich in the raw material into aromatics or alkylbenzenes, improve the yield of aviation kerosene, and realize the maximum production of aviation kerosene by direct coal liquefaction.

[0063] In some embodiments, in step (3), the alkylation reaction uses an alkylation catalyst; the alkylation catalyst includes an active component and a carrier; the active component includes at least one of Mo and Ni elements;

[0064] Optionally, the active component is a sulfide of a metal element; the weight content of the active component in the alkylation catalyst is 0.1% to 5% in terms of the metal element, specifically, for example, 0.1%, 0.5%, 0.6%, 1%, 2%, 3%, 4%, 5%; the carrier includes at least one of the molecular sieves; optionally, the molecular sieve includes at least one of ZSM-11 or MCM-22; the silicon-to-aluminum ratio of the molecular sieve, i.e., the silicon-to-aluminum molar ratio, is 20 to 200.

[0065] In the embodiment of the present invention, the alkylation reaction adopts a hydrogenation process, and in the presence of an alkylation catalyst, a mixed light oil fraction of coal direct liquefaction oil and methanol undergo an alkylation reaction to generate aviation kerosene distillate oil, making full use of the abundant and low-priced methanol resources, while achieving high-value utilization of methanol and reducing production costs. The method of the present invention adopts a hydrogenation process, which can greatly slow down the carbon deposition rate of the alkylation catalyst, extend the service life of the alkylation catalyst, and reduce the catalyst cost. Mo and Ni modified ZSM-11 or MCM-22 molecular sieve catalysts can greatly remove heteroatoms such as S and N, improve the quality of aviation kerosene, and at the same time can convert the light fraction into an aviation kerosene fraction of 170 to 300°C through an alkylation carbon increase reaction, thereby improving the utilization rate of coal direct liquefaction oil and methanol and increasing the yield of aviation kerosene components.

[0066] In some embodiments, in the step (3), the mass ratio of the hydrogenation catalyst to the alkylation catalyst is 1-2:1-2, specifically, 1-2 (e.g., 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2): 1-2 (e.g., 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2).

[0067] In some embodiments, in step (4), the first jet fuel fraction, the second jet fuel fraction and the third jet fuel fraction are subjected to hydrotreating treatment, and then subjected to gas-liquid separation and fractionation to obtain jet fuel.

[0068] In some embodiments, in step (4), the hydrotreating treatment is performed using a fixed bed reactor.

[0069] In some embodiments, in step (4), the reaction temperature of the hydrofining treatment is 260-400°C, specifically, for example, 260°C, 300°C, 345°C, 350°C, 355°C, 400°C; the reaction pressure is 6-17MPa, specifically, for example, 6MPa, 8MPa, 10MPa, 12MPa, 13MPa, 17MPa; the volume space velocity of the mixed jet fuel fraction is 0.2-2.0h -1 , specifically, for example, 0.2h -1 , 0.6h -1 , 0.8h -1 , 1.0h -1 , 1.5h -1 , 2.0h -1 ; The hydrogen-to-oil ratio is 500-2000, specifically, for example, 500, 800, 900, 1000, 2000.

[0070] In some embodiments, in step (4), the hydrotreating treatment uses a hydrotreating catalyst; the hydrotreating catalyst includes an active component and a carrier; the active component includes at least one of a VIB and VIII group metal element;

[0071] Optionally, the active component includes at least one of Ni, Mo, Co, and W metal elements; optionally, the active component is a sulfide of a metal element; the weight content of the active component in the hydrorefining catalyst is 0.2% to 20% in terms of metal element, specifically, for example, 0.2%, 0.5%, 1%, 2%, 5%, 10%, 15%, 20%; the carrier includes at least one of an inorganic oxide or a molecular sieve; the inorganic oxide includes at least one of alumina and silicon oxide.

[0072] In the embodiment of the present invention, the aviation kerosene fractions are mixed and subjected to hydrofining treatment to substantially remove heteroatoms such as S and N, thereby producing aviation kerosene with high quality and excellent performance.

[0073] An aviation kerosene according to an embodiment of the present invention is prepared by the method for preparing aviation kerosene according to an embodiment of the present invention. In the embodiment of the present invention, the aviation kerosene has a high yield and excellent fuel performance, and the high-value utilization of direct coal liquefaction oil is achieved while reducing the production cost of the aviation kerosene.

[0074] In some embodiments, the density of aviation kerosene is ≥ 0.89 g / cm 3 , the net calorific value of aviation kerosene is ≥43.0MJ / kg.

[0075] A system for preparing aviation kerosene according to an embodiment of the present invention comprises: a distillation separation unit 100, a hydrocracking unit 200, an alkylation and hydrogenation unit 300 and a hydrofining unit 400.

[0076] The distillation separation unit 100 is provided with a coal direct liquefied oil inlet, a first light oil fraction outlet, a first aviation kerosene fraction outlet and a heavy oil fraction outlet;

[0077] The hydrocracking unit 200 is provided with a heavy oil fraction inlet, a second light oil fraction outlet and a second jet fuel fraction outlet, and the heavy oil fraction inlet is connected to the heavy oil fraction outlet;

[0078] The alkylation and hydrogenation unit 300 is provided with a first light oil fraction inlet, a second light oil fraction inlet and a third jet fuel fraction outlet, the first light oil fraction inlet is connected to the first light oil fraction outlet, and the second light oil fraction inlet is connected to the second light oil fraction outlet;

[0079] The hydrotreating unit 400 is provided with a first jet fuel fraction inlet, a second jet fuel fraction inlet, a third jet fuel fraction inlet and a jet fuel outlet. The first jet fuel fraction inlet is connected to the first jet fuel fraction outlet, the second jet fuel fraction inlet is connected to the second jet fuel fraction outlet, and the third jet fuel fraction inlet is connected to the third jet fuel fraction outlet.

[0080] In the embodiment of the present invention, the aviation kerosene preparation system is used to implement the aviation kerosene preparation method described in the embodiment of the present invention or to prepare the aviation kerosene described in the embodiment of the present invention. The system for producing aviation kerosene can improve the conversion efficiency of coal direct liquefaction oil to prepare aviation kerosene, achieve maximum production of aviation kerosene from coal direct liquefaction oil, improve aviation kerosene yield and fuel performance, achieve high-value utilization of coal direct liquefaction oil while reducing production costs.

[0081] like Figure 1 As shown, the method for preparing aviation kerosene according to the embodiment of the present invention adopts the system for preparing aviation kerosene according to the embodiment of the present invention, comprising:

[0082] (1) Direct coal liquefaction oil 1 is fed into a distillation separation unit 100, and a first light oil fraction 2, a first jet fuel fraction 3, and a heavy oil fraction 4 are obtained by distillation;

[0083] (2) The heavy oil fraction 4 and hydrogen are sent to the hydrocracking unit 200, and hydrogen-rich gas and liquid oil products are obtained through hydrocracking reaction and gas-liquid separation; the liquid oil products are distilled to obtain a second light oil fraction 5 and a second jet fuel fraction 6; optionally, they are sent to the hydrocracking unit 200 through a high-pressure pump;

[0084] (3) mixing the first light oil fraction 2 and the second light oil fraction 5, and sending the mixed light oil fraction, methanol 7 and hydrogen to the alkylation and hydrogenation unit 300, performing alkylation reaction and hydrogenation reaction, and obtaining the third jet fuel fraction 8 and gas product 9 through gas-liquid separation and fractionation; optionally, sending them to the alkylation and hydrogenation unit 300 through a high-pressure pump;

[0085] (4) The first jet fuel fraction 3, the second jet fuel fraction 6 and the third jet fuel fraction 8 are sent to a hydrotreating unit 400 for hydrotreating reaction, and jet fuel 10 is obtained through gas-liquid separation and fractionation.

[0086] The present invention is described below with reference to specific embodiments. It should be noted that these embodiments are merely illustrative and do not limit the present invention in any way.

[0087] Example 1

[0088] A method for preparing aviation kerosene by directly liquefying coal oil, comprising:

[0089] (1) Using Yulin coal direct liquefaction oil as raw material oil, a first light oil fraction of less than 170°C, a first aviation kerosene fraction of 170-300°C, and a heavy oil fraction of more than 300°C were obtained by distillation separation; the properties of the raw material oil are shown in Table 1.

[0090] (2) The heavy oil fraction is mixed with hydrogen, subjected to hydrocracking reaction and gas-liquid separation, to obtain hydrogen-rich gas and liquid oil products; the liquid oil products are distilled to obtain a second light oil fraction of less than 170°C and a second jet fuel fraction of 170 to 300°C; the hydrocracking adopts a fixed bed reactor.

[0091] (3) The first light oil fraction and the second light oil fraction are mixed, and the mixed light oil fraction, methanol and hydrogen are subjected to alkylation reaction and hydrodeoxygenation, desulfurization and denitrogenation reaction, and the third jet fuel fraction of 170 to 300° C. is obtained by gas-liquid separation and fractionation. The alkylation reaction and hydrogenation reaction are carried out in a fixed bed reactor.

[0092] (4) The first jet fuel fraction, the second jet fuel fraction and the third jet fuel fraction are mixed and then subjected to a hydrotreating reaction, followed by gas-liquid separation and fractionation to obtain jet fuel at a temperature of 170 to 300° C. The hydrotreating reaction is carried out using a fixed bed reactor.

[0093] The specific parameters of the hydrocracking treatment, alkylation reaction and hydrogenation reaction, and hydrofining treatment are shown in Table 2. The main properties of the aviation kerosene of Example 1 are shown in Table 3.

[0094] Example 2

[0095] A method for preparing aviation kerosene by directly liquefying coal oil, comprising:

[0096] (1) Using Xinjiang coal direct liquefaction oil as raw material oil, a first light oil fraction of less than 230°C, a first aviation kerosene fraction of 230-300°C, and a heavy oil fraction of more than 300°C were obtained by distillation separation; the properties of the raw material oil are shown in Table 1.

[0097] (2) The heavy oil fraction is mixed with hydrogen, subjected to hydrocracking reaction and gas-liquid separation, to obtain hydrogen-rich gas and liquid oil products; the liquid oil products are distilled to obtain a second light oil fraction of less than 170°C and a second jet fuel fraction of 170 to 300°C; the hydrocracking adopts a fixed bed reactor.

[0098] (3) The first light oil fraction and the second light oil fraction are mixed, and the mixed light oil fraction, methanol and hydrogen are subjected to alkylation reaction and hydrodeoxygenation, desulfurization and denitrogenation reaction, and the third jet fuel fraction of 170 to 300° C. is obtained by gas-liquid separation and fractionation. The alkylation reaction and hydrogenation reaction are carried out in a fixed bed reactor.

[0099] (4) The first jet fuel fraction, the second jet fuel fraction and the third jet fuel fraction are mixed and then subjected to a hydrotreating reaction, followed by gas-liquid separation and fractionation to obtain jet fuel at a temperature of 170 to 300° C. The hydrotreating reaction is carried out using a fixed bed reactor.

[0100] The specific parameters of the hydrocracking treatment, alkylation reaction and hydrogenation reaction, and hydrofining treatment are shown in Table 2. The main properties of the aviation kerosene of Example 2 are shown in Table 3.

[0101] Example 3

[0102] A method for preparing aviation kerosene by directly liquefying coal oil, comprising:

[0103] (1) Inner Mongolia coal direct liquefaction oil is used as raw material oil, and a first light oil fraction of less than 220°C, a first aviation kerosene fraction of 220-300°C, and a heavy oil fraction of more than 300°C are obtained by distillation separation; the properties of the raw material oil are shown in Table 1.

[0104] (2) The heavy oil fraction is mixed with hydrogen, subjected to hydrocracking reaction and gas-liquid separation, to obtain hydrogen-rich gas and liquid oil products; the liquid oil products are distilled to obtain a second light oil fraction of less than 170°C and a second jet fuel fraction of 170 to 300°C; the hydrocracking adopts a fixed bed reactor.

[0105] (3) The first light oil fraction and the second light oil fraction are mixed, and the mixed light oil fraction, methanol and hydrogen are subjected to alkylation reaction and hydrodeoxygenation, desulfurization and denitrogenation reaction, and the third jet fuel fraction of 170 to 300° C. is obtained by gas-liquid separation and fractionation. The alkylation reaction and hydrogenation reaction are carried out in a fixed bed reactor.

[0106] (4) The first jet fuel fraction, the second jet fuel fraction and the third jet fuel fraction are mixed and then subjected to a hydrotreating reaction, followed by gas-liquid separation and fractionation to obtain jet fuel at a temperature of 170 to 300° C. The hydrotreating reaction is carried out using a fixed bed reactor.

[0107] The specific parameters of the hydrocracking treatment, alkylation reaction and hydrogenation reaction, and hydrofining treatment are shown in Table 2. The main properties of the aviation kerosene of Example 3 are shown in Table 3.

[0108] Comparative Example 1

[0109] A method for preparing aviation kerosene by directly liquefying coal oil, comprising:

[0110] (1) The Yulin coal direct liquefaction oil in Example 1 is used as the raw material oil, and is separated by distillation to obtain a first light oil fraction of <170°C, a first aviation kerosene fraction of 170-300°C, and a heavy oil fraction of >300°C; the properties of the raw material oil are shown in Table 1.

[0111] (2) The heavy oil fraction is mixed with hydrogen, subjected to hydrocracking reaction and gas-liquid separation, to obtain hydrogen-rich gas and liquid oil products; the liquid oil products are distilled to obtain a second light oil fraction of less than 170°C and a second jet fuel fraction of 170 to 300°C; the hydrocracking adopts a fixed bed reactor.

[0112] (3) The first jet fuel fraction and the second jet fuel fraction are mixed and then subjected to a hydrotreating reaction, followed by gas-liquid separation and fractionation to obtain jet fuel at 170 to 300° C. The hydrotreating reaction is performed using a fixed bed reactor.

[0113] The specific parameters of the hydrocracking treatment, alkylation reaction and hydrogenation reaction, and hydrofining treatment are shown in Table 2. The main properties of the aviation kerosene of Comparative Example 1 are shown in Table 3.

[0114] Table 1 Properties of coal direct liquefaction oil of Examples 1-3

[0115]

[0116] Table 2 Main process conditions of Examples 1-3 and Comparative Example 1

[0117]

[0118]

[0119] Table 3 Main properties of the aviation kerosene products of Examples 1-3 and Comparative Example 1

[0120]

[0121] It can be seen from Table 2 and Table 3 that the preparation method of the embodiment of the present invention obtains aviation kerosene by subjecting coal direct liquefaction oil to hydrogenation reaction and methanol alkylation reaction and other processes. The density of aviation kerosene is high, higher than 0.89 g / cm 3 The aviation kerosene yield is high, reaching more than 82%. Based on the high-value utilization of direct coal liquefaction oil, maximization of aviation kerosene yield and cost reduction, aviation kerosene has a higher net calorific value of quality, higher than 43.0MJ / kg.

[0122] Compared with Example 1, the aviation kerosene yield of Comparative Example 1 is lower, because Comparative Example 1 fails to make full use of the light oil fraction in the direct coal liquefaction oil and the light oil fraction generated by the hydrocracking of the heavy oil fraction. In the alkylation reaction and hydrogenation reaction steps of the present invention, the provided hydrogenation conditions and the single metal active component hydrogenation catalyst containing Cu can efficiently carry out the hydrodeoxygenation reaction, so that the phenolic substances rich in the light oil fraction are converted into aromatics or alkylbenzenes, and the aviation kerosene fraction yield is improved; the Mo and Ni modified MCM-22 or ZSM-11 molecular sieve catalyst provided by the present invention can greatly remove heteroatoms such as S and N, and at the same time, the light oil fraction is converted into an aviation kerosene fraction of 170 to 300 ° C through the alkylation carbon increase reaction, thereby improving the utilization rate of direct coal liquefaction oil and methanol, and maximizing the aviation kerosene component yield. In Table 3, the sulfur of the aviation kerosene of the embodiment of the present invention is less than 3 mg / L, and the nitrogen is less than 5 mg / L, and the sulfur and nitrogen are removed. Through alkylation reaction, hydrogenation reaction, hydrorefining treatment and other processes, heteroatoms such as S and N are largely removed, the quality of aviation kerosene is improved, and high-quality aviation kerosene with excellent performance is obtained.

[0123] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0124] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0125] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0126] Although the above embodiments have been shown and described, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those of ordinary skill in the art are all within the scope of protection of the present invention.

Claims

1. A method for preparing aviation kerosene, characterized in that: The following steps are involved: (1) distilling the coal direct liquefaction oil to obtain a first light oil fraction, a first aviation kerosene fraction and a heavy oil fraction; (2) treating the heavy oil fraction by hydrocracking to obtain a second light oil fraction and a second jet fuel fraction; (3) mixing the first light oil fraction and the second light oil fraction, and subjecting the mixture to an alkylation reaction and a hydrogenation reaction to obtain a third jet fuel fraction; (4) The first jet fuel fraction, the second jet fuel fraction and the third jet fuel fraction are subjected to a hydrotreating treatment to obtain jet fuel.

2. The method for preparing aviation kerosene according to claim 1, characterized in that: The cutting temperature of the first light oil fraction or the second light oil fraction is independently 170-230°C; And / or, the cutting temperature of the heavy oil fraction is 280-300°C.

3. The method for preparing aviation kerosene according to claim 1, characterized in that: In the step (2), the hydrocracking treatment adopts a fixed bed reactor; And / or, the reaction temperature of the hydrocracking treatment is 320-470°C, the reaction pressure is 8-19 MPa, and the volume space velocity of the heavy oil fraction is 0.2-2.0 h -1 , hydrogen to oil volume ratio is 500-2000; And / or, the hydrocracking treatment uses a hydrocracking catalyst; the hydrocracking catalyst includes an active component and a carrier; the active component includes at least one of Group VIB and Group VIII metal elements; the weight content of the active component in the hydrocracking catalyst is 0.2% to 20% in terms of metal elements; the carrier includes at least one of an inorganic oxide or a molecular sieve.

4. The method for preparing aviation kerosene according to claim 1, characterized in that: In the step (3), the first light oil fraction and the second light oil fraction are mixed, and subjected to alkylation reaction and hydrogenation reaction with methanol and hydrogen to obtain a third jet fuel fraction; And / or, the alkylation reaction and hydrogenation reaction adopt a fixed bed reactor; And / or, the reaction temperature of the alkylation reaction and the hydrogenation reaction is 200-460°C, and the volume space velocity of the mixed light oil fraction is 5-15h -1 , the reaction pressure is 4-20MPa, and the hydrogen-to-oil volume ratio is 5-20.

5. The method for preparing aviation kerosene according to claim 4, characterized in that: In the step (3), the molar ratio of methanol to mixed light oil fraction is (0.5-2):

3.

6. The method for preparing aviation kerosene according to claim 1, characterized in that: In the step (3), the hydrogenation reaction uses a hydrogenation catalyst; the hydrogenation catalyst includes an active component and a carrier; the active component of the hydrogenation catalyst includes Cu element; the weight content of the active component in the hydrogenation catalyst is 0.1-8% in terms of metal element.

7. The method for preparing aviation kerosene according to claim 1, characterized in that: In the step (3), the alkylation reaction uses an alkylation catalyst; the alkylation catalyst includes an active component and a carrier; the active component includes at least one of Mo and Ni elements; the weight content of the active component in the alkylation catalyst is 0.1% to 5% as a metal element; the carrier includes at least one of molecular sieves; the molecular sieve includes at least one of ZSM-11 and MCM-22.

8. The method for preparing aviation kerosene according to claim 1, characterized in that: In the step (4), the hydrofining treatment adopts a fixed bed reactor; And / or, the reaction temperature of the hydrofining treatment is 260-400°C, the reaction pressure is 6-17 MPa, and the volume space velocity of the mixed aviation kerosene fraction is 0.2-2.0 h -1 , hydrogen-to-oil ratio is 500-2000; And / or, the hydrorefining treatment uses a hydrorefining catalyst; the hydrorefining catalyst includes an active component and a carrier; the active component includes at least one of VIB and VIII group metal elements; the weight content of the active component in the hydrorefining catalyst is 0.2% to 20% in terms of metal elements; the carrier includes at least one of an inorganic oxide or a molecular sieve.

9. An aviation kerosene, characterized in that: The aviation kerosene is prepared by the method for preparing aviation kerosene according to any one of claims 1 to 8.

10. A system for preparing aviation kerosene, characterized in that: include: A distillation separation unit, wherein the distillation separation unit is provided with a coal direct liquefied oil inlet, a first light oil fraction outlet, a first aviation kerosene fraction outlet and a heavy oil fraction outlet; A hydrocracking unit, wherein the hydrocracking unit is provided with a heavy oil fraction inlet, a second light oil fraction outlet and a second jet fuel fraction outlet, and the heavy oil fraction inlet is connected to the heavy oil fraction outlet; An alkylation and hydrogenation unit, wherein the alkylation and hydrogenation unit is provided with a first light oil fraction inlet, a second light oil fraction inlet and a third jet fuel fraction outlet, wherein the first light oil fraction inlet is connected to the first light oil fraction outlet, and the second light oil fraction inlet is connected to the second light oil fraction outlet; The hydrotreating unit is provided with a first jet fuel fraction inlet, a second jet fuel fraction inlet, a third jet fuel fraction inlet and a jet fuel outlet, wherein the first jet fuel fraction inlet is connected to the first jet fuel fraction outlet, the second jet fuel fraction inlet is connected to the second jet fuel fraction outlet, and the third jet fuel fraction inlet is connected to the third jet fuel fraction outlet.

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