CN109988609B

CN109988609B - Flexible shale oil hydrocracking process

Info

Publication number: CN109988609B
Application number: CN201711468822.2A
Authority: CN
Inventors: 刘涛; 李宝忠; 张忠清; 孙士可; 王岩; 方向晨
Original assignee: China Petroleum and Chemical Corp; Sinopec Dalian Research Institute of Petroleum and Petrochemicals
Current assignee: Sinopec Dalian Petrochemical Research Institute Co ltd; China Petroleum and Chemical Corp
Priority date: 2017-12-29
Filing date: 2017-12-29
Publication date: 2021-05-04
Anticipated expiration: 2037-12-29
Also published as: CN109988609A

Abstract

The invention discloses a flexible shale oil hydrocracking process. Carrying out hydrogenation pretreatment on a shale oil raw material, then carrying out gas-liquid separation, enabling the obtained liquid phase to enter a hydrocracking pretreatment reactor, then entering a hydrocracking reactor, and dividing the material passing through an upper hydrocracking catalyst bed layer into two parts; one material is pumped out of the hydrocracking reactor through the middle of the bed layer and enters the hydroisomerization cracking reactor to carry out an isomerization cracking reaction; the other material continuously flows downwards through a lower hydrocracking catalyst bed layer; and respectively carrying out gas-liquid separation and fractionation on the hydrocracking reaction material and the hydroisomerization cracking reaction material to obtain naphtha, aviation kerosene, diesel oil and tail oil products with different specifications. The invention provides a hydrocracking process for simultaneously producing more than two distillate oil and tail oil with different specifications on a set of hydrocracking process device, which can fully utilize the heat carried by part of cracked materials to realize the coupling operation of a hydrocracking reactor and a hydroisomerization cracking reactor.

Description

Flexible shale oil hydrocracking process

Technical Field

The invention belongs to the field of petroleum refining, and particularly relates to a hydrocracking process for flexibly producing high-quality light naphtha, heavy naphtha, aviation kerosene, diesel oil and tail oil products with different properties by using shale oil as raw oil.

Background

Shale oil is a liquid product obtained by heating and decomposing kerogen in oil shale, the shale oil contains a large amount of unsaturated hydrocarbons, also contains non-hydrocarbon compounds such as sulfur, nitrogen and oxygen, and also contains higher-content metal impurities, and generally the shale oil has relatively higher paraffin content, namely higher condensation point. The hydrogenation technology is an important processing means for the lightening of heavy oil and the upgrading of the quality of light oil. The hydrocracking technology has the advantages of strong raw oil adaptability, good product flexibility, high liquid product yield, high product quality and the like, and is developed quickly. The existing hydrocracking technology can be divided into three types according to the processing flow: a one-stage series hydrocracking process flow, a single-stage hydrocracking process flow and a two-stage hydrocracking process flow. The operation can be divided into three types according to whether the tail oil is circulated or not: a single-pass once-through process flow, a partial circulation process flow and a full circulation process flow. The hydrocracking technology uses two types of catalysts, namely a hydrocracking pretreatment catalyst and a hydrocracking catalyst, wherein the hydrocracking catalyst can be divided into different types of catalysts according to different cracking components, and the main cracking components comprise amorphous silica-alumina, a Y-type molecular sieve, a beta-type molecular sieve, an SAPO-series molecular sieve, a ZSM-5 molecular sieve and the like. When different types of hydrocracking components are used, the composition and the property of the obtained light oil are greatly different, and the composition and the property of tail oil are also greatly different.

CN102453537A discloses a hydrocracking method for shale oil, which comprises, first, subjecting shale oil to hydrogenation pretreatment, fractionating the hydrogenation pretreatment product stream, and subjecting the obtained tail oil to hydrocracking, wherein only one type of hydrocracking catalyst is used. CN101942333A discloses a shale oil one-stage series hydrocracking process, wherein the hydrocracking reactor is operated by gas-liquid countercurrent method and only one type of hydrocracking catalyst is used. Thus the products of each fraction obtained in the above hydrocracking process are of only one specification.

CN103055922B discloses a preparation method of a bulk phase hydrocracking catalyst, and CN105018139B, CN 001293228A, CN001508225A and CN104611020B all disclose a method for grading two different Y-type molecular sieves in a hydrocracking method of low energy consumption high yield high quality chemical raw materials. The technology can produce high-quality products by using a hydrocracking method containing a Y-type molecular sieve hydrocracking catalyst by using wax oil as raw oil, wherein the tail oil has high alkane content and low BMCI value and is a raw material for preparing ethylene by high-quality steam cracking, but the product of each fraction obtained by hydrocracking has only one specification.

CN105582992A discloses a hydroisomerization catalyst, a preparation method and application thereof, and a hydrocracking tail oil hydroisomerization method, which can produce high-quality products by using a hydrocracking method containing an isomerization type molecular sieve hydrocracking catalyst and taking wax oil as raw oil, wherein the tail oil has high isomerization content, low condensation point and high viscosity index and is a raw material of high-quality lubricating oil base oil, but the product of each fraction obtained by hydrocracking only has one specification.

CN103394368B discloses a light oil type hydrocracking catalyst containing a composite molecular sieve, a preparation method and an application thereof, CN103551186B discloses a medium oil type hydrocracking catalyst containing a composite molecular sieve, a preparation method and an application thereof, and US4837396A discloses a preparation of a composite molecular sieve catalyst. The technology can produce various high-quality hydrocracking products by using a hydrocracking method of a hydrocracking catalyst containing a Y-type molecular sieve and an isomeric molecular sieve composite molecular sieve by using wax oil as raw oil, but the product of each fraction has only one specification.

CN001169919C discloses a method for increasing the yield of high-quality diesel oil by distillate oil. The technology can produce various high-quality hydrocracking products by using wax oil as raw oil and simultaneously using a hydrocracking method containing two catalysts, namely a Y-type molecular sieve catalyst and an isomeric molecular sieve hydrocracking catalyst, but the product of each fraction has only one specification.

In conclusion, compared with the existing hydrocracking technology using two different types of molecular sieve catalysts and the hydrocracking technology using the Y-type molecular sieve hydrocracking catalyst, the obtained heavy naphtha product has low sulfur content, relatively high aromatic hydrocarbon potential, relatively high smoke point of aviation kerosene products, low sulfur content of diesel oil products, high cetane number, but relatively high condensation point, low aromatic hydrocarbon content of tail oil products, relatively low density, relatively low BMCI value, but very high condensation point which is usually more than 30 ℃; by using a hydrocracking technology of an isomeric molecular sieve hydrocracking catalyst, the obtained heavy naphtha product has low sulfur content, slightly low aromatic hydrocarbon potential, low sulfur content and low condensation point of a diesel product, but has relatively slightly low cetane number and relatively high tail oil density, but has high content of isomeric hydrocarbon and very low condensation point which is usually less than 0 ℃; the hydrocracking technology using the Y-heterogeneous compound molecular sieve-containing catalyst or the hydrocracking technology using the Y-heterogeneous compound molecular sieve-containing hydrocracking catalyst and the heterogeneous molecular sieve-containing hydrocracking catalyst in a grading manner, and the property of the obtained tail oil is between that of the Y-heterogeneous compound molecular sieve-containing hydrocracking catalyst and that of the heterogeneous molecular sieve-containing hydrocracking catalyst. The hydrocracking process technology has the advantages that the hydrocracking tail oil products produced at the same conversion rate are greatly different, wherein the tail oil using the Y-type molecular sieve catalyst is a high-quality raw material for preparing ethylene through steam cracking, the tail oil using the heterogeneous molecular sieve catalyst is a raw material capable of directly producing high-quality lubricating oil base oil or serving as the high-quality lubricating oil base oil, and the tail oil obtained by using the Y-heterogeneous compound molecular sieve-containing catalyst or grading the Y-type molecular sieve-containing hydrocracking catalyst and the heterogeneous molecular sieve-containing hydrocracking catalyst can be used as a raw material for preparing ethylene through steam cracking or serving as a raw material for the high-quality lubricating oil base oil. Therefore, when the above hydrocracking processes are used alone, different types of hydrocracking catalysts can be selected according to requirements, or two molecular sieve composite catalysts are used, or two hydrocracking catalysts are selected for use in a grading manner, but the processes can only produce tail oil products with one property, namely, the operation flexibility is relatively poor.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a flexible shale oil hydrocracking process, namely, a hydrogenation pretreatment technology is used, partial reaction material flow is extracted from the middle part of a hydrocracking reactor using a Y-shaped hydrocracking catalyst, and high-quality ethylene raw material prepared by steam cracking, high-quality lubricating oil base oil raw material, naphtha products with various specifications and high-quality motor fuel products are flexibly produced from the shale oil raw material oil by a Y-shaped hydrocracking catalyst hydrocracking and heterogeneous hydrocracking catalyst hydrocracking combined method.

The invention relates to a flexible shale oil hydrocracking process, which comprises the following steps:

a. the method comprises the following steps that firstly, shale oil raw oil enters a hydrogenation pretreatment reactor under a hydrogenation pretreatment condition and passes through a hydrogenation pretreatment catalyst bed layer, and an obtained hydrogenation pretreatment material flow is separated in a high-pressure separator to obtain hydrogenation pretreatment high-pressure hydrogen-rich gas and a liquid-phase material flow;

b. b, allowing the liquid phase material flow obtained in the step a to enter a hydrocracking pretreatment reactor under a hydrocracking pretreatment condition and pass through a hydrocracking pretreatment catalyst bed layer, allowing the hydrocracking pretreatment material flow to pass through a first hydrocracking catalyst bed layer containing a Y-type molecular sieve catalyst in the hydrocracking reactor under the hydrocracking condition to obtain a first hydrocracking material flow, dividing the part of the material flow into two parts, and extracting one part of the material flow out of the hydrocracking reactor;

c. b, continuously allowing the rest part of the first hydrocracking material flow in the step b to pass through a second hydrocracking catalyst bed layer containing a Y-type molecular sieve catalyst in a hydrocracking reactor under a hydrocracking condition, and separating and fractionating a hydrocracking material flow to obtain a hydrocracking high-pressure hydrogen-rich gas, a hydrocracking gas product, a hydrocracking naphtha product, a hydrocracking aviation kerosene product, a hydrocracking diesel oil product and a hydrocracking tail oil product;

d. and c, allowing the first hydrocracking material flow extracted from the reactor in the step b to pass through a hydroisomerization cracking catalyst bed layer containing an isomerization type molecular sieve catalyst in a hydroisomerization cracking reactor under the hydroisomerization cracking condition, and separating and fractionating the hydroisomerization cracking material flow to obtain a hydroisomerization cracking high-pressure hydrogen-rich gas, a hydroisomerization cracking gas product, a hydroisomerization cracking naphtha product, a hydroisomerization cracking aviation kerosene product, a hydroisomerization cracking diesel product and a hydroisomerization cracking tail oil product.

The hydrocracking process according to the present invention may further comprise a step e: and d, mixing the hydrogenation pretreatment high-pressure hydrogen-rich gas obtained in the step a, the hydrocracking high-pressure hydrogen-rich gas obtained in the step c and the hydroisomerization cracking high-pressure hydrogen-rich gas obtained in the step d for recycling.

The shale oil raw material oil contains S, N, O and metal impurities, particularly metal can cause the blockage of a reactor inlet to cause pressure drop and blockage of a hydrocracking pretreatment catalyst pore channel to cause permanent inactivation of the catalyst, and water generated by O hydrogenation reaction can cause the collapse of a molecular sieve in the hydrocracking catalyst to cause the inactivation of the hydrocracking catalyst and even crushing. When raw oil passes through a hydrogenation pretreatment catalyst, O and metals are effectively removed, S, N is removed to a certain extent, aromatic hydrocarbons are hydrogenated and saturated to a certain extent, water and liquid phase material flow are separated after material flow subjected to hydrogenation pretreatment is separated by a high-pressure separator, and S, N is effectively removed when the liquid phase material flow continuously passes through the hydrocracking pretreatment catalyst, the aromatic hydrocarbon is further hydrogenated and saturated, when the hydrocracking pretreatment material flow continuously passes through a hydrocracking catalyst bed layer containing a Y-type molecular sieve catalyst, part of ring-opening reaction of the cyclic hydrocarbon occurs, the aromatic hydrocarbon is further subjected to hydrogenation saturation, the macromolecule is cracked into micromolecule, one part of hydrocracking material flow is continuously subjected to hydrocracking, because the Y-type molecular sieve has the characteristic of preferentially cracking macromolecular cyclic hydrocarbon, can obtain aviation kerosene products, diesel oil products and tail oil products with high normal hydrocarbon content and low aromatic hydrocarbon content; and (3) after a part of the extracted first hydrocracking material flow passes through a hydroisomerization cracking catalyst containing an isomerization type molecular sieve catalyst, continuing isomerization hydrocracking, wherein the isomerization hydrocracking product with high isomerization hydrocarbon content can be obtained due to the characteristics of isomerization and cracking of the isomerization type molecular sieve, and particularly, the diesel oil and diesel oil product has low condensation point, the tail oil product has low condensation point and high viscosity index.

Compared with the prior art, the flexible shale oil hydrocracking process has the advantages that:

1. according to the invention, through the hydrogenation pretreatment process, O in the shale oil can be removed and separated, so that fatal influence of water generated by hydrogenation on subsequent catalysts, especially a hydrocracking catalyst and a hydroisomerization cracking catalyst, is avoided, and meanwhile, metal is removed and is remained in the hydrogenation pretreatment reactor, so that the influence on the hydrocracking pretreatment reactor and the catalyst is reduced, and the service lives of the subsequent hydrocracking pretreatment catalyst, the hydrocracking catalyst and the hydroisomerization cracking catalyst are prolonged.

2. In the invention, the hydrocracking reactor comprises at least two hydrocracking catalyst beds. Through the step of extracting the cracking materials arranged in the middle of the bed layer of the hydrocracking reactor, the hydrocracking material strands can be effectively distributed without special operation, and the obtained materials are subjected to different hydrocracking processes, so that target products with different specifications, particularly tail oil products, can be flexibly produced. At the same time, it is technically easy to extract the reactant stream in the middle of the reactor bed. In the prior art, although a plurality of light products can be obtained by adjusting the conversion rate and the distillation range of the products, only one type of light naphtha products, heavy naphtha products, aviation kerosene products and diesel oil products can be generally obtained in the same distillation range of a set of hydrocracking unit, and particularly only one type of tail oil products can be obtained because only one hydrocracking reactor outlet is arranged; if different specifications of hydrocracking products are required, more than two sets of hydrocracking units are required. Therefore, the invention provides a hydrocracking process for simultaneously producing more than two same-fraction ranges, but different specifications of tail oil products, more than two different specifications of aviation kerosene products, more than two different specifications of diesel oil products and a plurality of different specifications of naphtha products on one hydrocracking process device for the first time.

3. According to the invention, the first hydrocracking material flow extracting device is arranged in the middle of the catalyst bed layer of the hydrocracking reactor, the first hydrocracking material flow obtained by subjecting a shale oil raw material to hydrogenation pretreatment, hydrocracking pretreatment and hydrocracking is extracted out of the reactor and is respectively sent into the independently arranged hydrocracking reactors to carry out the hydroisomerization cracking reaction, and the condensation point of the hydrocracked material is further reduced, so that naphtha products, aviation kerosene products, diesel oil products and tail oil products with different aromatic hydrocarbon contents and different isomeric hydrocarbon contents can be flexibly produced by the method.

4. In the invention, heavy naphtha obtained by hydrocracking a product obtained by fractionating the material flows of two reactors by using a catalyst containing a Y-type molecular sieve has relatively high aromatic hydrocarbon potential, a aviation kerosene product has relatively high smoke point, a diesel oil product has relatively high cetane number, a tail oil product has high paraffin content and a BMCI value is relatively low; the naphtha obtained by partial hydrocracking of the catalyst containing the Y-type molecular sieve and the hydroisomerization of the catalyst containing the heterogeneous molecular sieve has high content of isomeric hydrocarbon, low freezing point of aviation kerosene products, low condensation point of diesel oil products, high content of isomeric hydrocarbon of tail oil products, large viscosity index and low condensation point; can respectively meet the requirements of producing naphtha, aviation kerosene products, diesel oil products and tail oil products with different specifications.

5. In the invention, the liquid obtained in the middle of the hydrocracking catalyst bed layer of the hydrocracking reactor has very high temperature and pressure, and can directly enter a newly arranged hydrocracking reactor for reaction, thereby fully utilizing the heat carried by the part of cracking materials and realizing the coupling operation of the hydrocracking reactor and the hydrocracking reactor.

Drawings

Fig. 1 is a schematic flow chart of the principle of the present invention.

Wherein: 1-shale oil raw oil, 2-hydrogenation pretreatment reactor, 3-hydrocracking pretreatment reactor, 4-hydrocracking reactor, 5-hydrocracking raw material flow, 6-hydrocracking material flow, 7-hydrocracking reactor, 8-hydrocracking high-pressure separator, 9-hydrocracking high-pressure separator, 10-hydrocracking fractionating tower, 11-hydrocracking fractionating tower, 12-hydrocracking light naphtha product, 13-hydrocracking heavy naphtha product, 14-hydrocracking aviation kerosene product, 15-hydrocracking diesel oil product, 16-hydrocracking tail oil product, 17-hydrocracking light naphtha product, 18-hydrocracking heavy naphtha product, 19-hydrocracking aviation kerosene product, 20-hydroisomerized cracked diesel oil product, 21-hydroisomerized cracked tail oil product, 22-hydrocracking high-pressure separator hydrogen-rich gas, 23-hydroisomerized cracked high-pressure separator hydrogen-rich gas, 24-make-up hydrogen, 25-hydrotreating high-pressure separator, 26-hydrotreating high-pressure separator hydrogen-rich gas, and 27-hydrotreating high-pressure separator liquid phase material flow.

Detailed Description

The initial boiling point of the shale oil raw material in the step a is 100-400 ℃, and the final boiling point is 400-650 ℃. The shale oil raw material oil can be shale oil obtained from oil shale, or mixed oil of one or more of coal tar obtained from coal, direct coal liquefaction oil, indirect coal liquefaction oil, synthetic oil and the like, or straight run wax oil, coking wax oil, catalytic cycle oil and the like obtained from petroleum.

The hydrogenation pretreatment catalyst in the step a and the hydrocracking pretreatment catalyst in the step b are conventional hydrogenation catalysts. Generally, metals in a VIB group and/or a VIII group are used as active components, alumina or silicon-containing alumina is used as a carrier, the metals in the VIB group are generally Mo and/or W, and the metals in the VIII group are generally Co and/or Ni. Based on the weight of the catalyst, the content of the VIB group metal is 10-35 wt% calculated by oxide, the content of the VIII group metal is 3-15 wt% calculated by oxide, and the properties are as follows: the specific surface area is 100 to 650m²The pore volume is 0.15 to 0.6 mL/g. The main catalysts comprise hydrogenation pretreatment catalysts such as 3936, 3996, FF-16, FF-26, FF-36, FF-46 and FF-56 series developed by the petrochemical research institute, and can also be similar catalysts with functions developed by domestic and foreign catalyst companies, such as HC-K, HC-P of UOP company, TK-555 and TK-565 of Topsoe company, KF-847 and KF-848 of Akzo company, and the like. The hydrotreating catalyst and the hydrocracking catalyst may be the same or different. The hydrogenation pretreatment operation condition can adopt the conventional operation condition, generally the reaction pressure is 3.0MPa to 19.0MPa, the reaction temperature is 260 ℃ to 430 ℃, and the liquid hourly volume space velocity is 0.2h^-1～6.0h^-1The volume ratio of the hydrogen to the oil is 100: 1-2000: 1.

And (b) filling a hydrogenation protective agent and a hydrodemetallization catalyst on the hydrogenation pretreatment catalyst in the step a. Wherein the hydrogenation protective agent accounts for 5-20% of the total catalyst volume of the hydrogenation pretreatment reactor, and the hydrogenation demetalization catalyst accounts for 10-40% of the total catalyst volume of the hydrogenation pretreatment reactor.

The high pressure separator described in step a is a conventional separator operating at reaction pressure conditions.

The liquid phase stream in the step a does not contain water generated by the reaction or water brought in from the outside. The total metal content in the liquid phase logistics is not more than 5 [ mu ] g/g, preferably not more than 3 [ mu ] g/g.

The hydrocracking pretreatment operation condition of the step b can adopt the common conditionsThe operating conditions of the reactor are that the reaction pressure is 3.0MPa to 19.0MPa, the reaction temperature is 300 ℃ to 450 ℃, and the liquid hour volume space velocity is 0.2h^-1～6.0h^-1The volume ratio of the hydrogen to the oil is 100: 1-2000: 1.

The hydrocracking catalyst in the step b and the step c is a conventional hydrocracking catalyst. Generally, metals in a VIB group and/or a VIII group are used as active components, the metals in the VIB group are generally Mo and/or W, and the metals in the VIII group are generally Co and/or Ni. The catalyst carrier contains one or more of alumina, siliceous alumina and molecular sieve, preferably Y-type molecular sieve. Based on the weight of the catalyst, the content of the VIB group metal is 10-35 wt% calculated by oxide, the content of the VIII group metal is 3-15 wt% calculated by oxide, and the content of the Y type molecular sieve is 5-80 wt%. The main catalysts are 3824, 3825, 3976, FC-12, FC-24, FC-26, FC-32, FC-50 catalysts and the like developed by the petrochemical research institute, HC-12, HC-14, HC-24, HC-39 and the like of UOP company. For hydrocracking catalysts, certain hydrogenation activity and certain cracking activity are required, so that hydrogenation saturation of olefins and aromatics in hydrotreating generated oil and fractions generated in a hydrocracking process is ensured, and ring-opening reaction of saturated aromatics is also required.

The hydrocracking conditions described in step b may be conventional operating conditions and are generally: the reaction pressure is 3.0MPa to 19.0MPa, the reaction temperature is 300 ℃ to 450 ℃, and the liquid hourly volume space velocity is 0.2h^-1～6.0h^-1The volume ratio of the hydrogen to the oil is 100: 1-2000: 1.

And b, taking the part of the extracted material flow in the step b as a liquid phase, wherein the part of the extracted material flow accounts for 5-95 wt% of the raw oil, and preferably 10-80 wt%.

The hydrocracking conditions described in step c may be conventional and are generally: the reaction pressure is 3.0MPa to 19.0MPa, the reaction temperature is 300 ℃ to 450 ℃, and the liquid hourly volume space velocity is 0.2h^-1～6.0h^-1The volume ratio of the hydrogen to the oil is 100: 1-2000: 1.

The separation described in step c generally comprises separating two parts for a hydrocracking high-pressure separator and a low-pressure separator. Wherein the high-pressure separator separates to obtain the hydrocracking high-pressure hydrogen-rich gas and liquid, and the liquid separated by the high-pressure separator enters the low-pressure separator. The low pressure separator separates the high pressure liquid product to yield a hydrocarbon-rich gas and a low pressure liquid product. The hydrocarbon-rich gas is separated to obtain the required hydrocracking gas product.

The fractionation described in step c is carried out in a hydrocracking fractionator system. And fractionating the low-pressure liquid product in a fractionating tower to obtain a hydrocracking light naphtha product, a hydrocracking heavy naphtha product, a hydrocracking aviation kerosene product, a hydrocracking diesel oil product and a hydrocracking tail oil product.

The hydroisomerization cracking catalyst in the step d is a conventional hydroisomerization cracking catalyst. Generally, metals in a VIB group and/or a VIII group are used as active components, the metals in the VIB group are generally Mo and/or W, and the metals in the VIII group are generally Co and/or Ni. The carrier of the catalyst is one or more of alumina, silicon-containing alumina and molecular sieve, preferably molecular sieve, and the molecular sieve can be beta type molecular sieve, Sapo type molecular sieve, etc. Based on the weight of the catalyst, the content of the VIB group metal is 10-35 wt% calculated by oxide, the content of the VIII group metal is 3-15 wt% calculated by oxide, and the content of the molecular sieve is 5-80 wt%. The main catalysts comprise FC-14, FC-20 and the like developed by the petrochemical research institute. For hydrocracking catalysts, certain hydrogenation activity and certain cracking activity are required, and both the hydrogenation saturation of olefins and aromatics in reaction materials and the isomerization of straight-chain paraffins are required. The hydroisomerization cracking may be carried out under conventional operating conditions, which are generally: the reaction pressure is 3.0MPa to 19.0MPa, the reaction temperature is 300 ℃ to 450 ℃, and the liquid hourly volume space velocity is 0.2h^-1～6.0h^-1The volume ratio of the hydrogen to the oil is 100: 1-2000: 1.

The separation described in step d is carried out in a hydroisomerization cracking high pressure separator and a low pressure separator. Wherein, the hydroisomerization cracking high-pressure separator separates to obtain the hydroisomerization cracking high-pressure hydrogen-rich gas and liquid, and the liquid separated by the high-pressure separator enters the low-pressure separator. The low pressure separator separates the high pressure liquid product to yield a hydrocarbon-rich gas and a low pressure liquid product. The hydrocarbon-rich gas is separated to obtain the required hydroisomerized cracked gas product.

The fractionation described in step d is carried out in a hydroisomerization cracking fractionator system. And fractionating the low-pressure liquid product in a fractionating tower to obtain a hydroisomerized cracked light naphtha product, a hydroisomerized cracked heavy naphtha product, a hydroisomerized cracked aviation kerosene product, a hydroisomerized cracked diesel oil product and a hydroisomerized cracked tail oil product.

The hydrocracking gas product and the hydroisomerization gas product in step c and step d can be used as products independently or can be mixed into a mixed gas product.

The hydrocracked light naphtha product and the hydroisomerized cracked light naphtha product in the step c and the step d can be used as the products independently or can be mixed into a mixed light naphtha product.

The hydrocracked heavy naphtha product and the hydroisomerized cracked heavy naphtha product in the step c and the step d can be used as the products independently or can be mixed into a mixed heavy naphtha product.

The hydrocracking aviation kerosene product and the hydroisomerization cracking aviation kerosene product in the step c and the step d can be independently used as products, and can also be mixed into a mixed aviation kerosene product.

The hydrocracking diesel oil product and the hydroisomerization diesel oil product in the step c and the step d can be used as products independently or can be mixed into a mixed diesel oil product.

And d, taking the hydrocracking tail oil in the step c as a product.

And d, independently using the hydroisomerized cracked tail oil in the step d as a product.

And e, mixing the high-pressure hydrogen-rich gas in the step e, and then directly using the mixed gas as recycle hydrogen, or recycling the mixed gas after hydrogen sulfide is removed by a recycle hydrogen desulfurization system.

With reference to fig. 1, the method of the present invention is as follows: the method comprises the steps of firstly mixing shale oil raw oil 1 with recycle hydrogen and entering the hydrogenation pretreatment reactor 2, introducing hydrogenation pretreatment material flow into a hydrogenation pretreatment high-pressure separator 25 for gas-liquid separation, separating to obtain hydrogenation pretreatment high-pressure hydrogen-rich gas 26 and hydrogenation pretreatment high-pressure separator liquid-phase material flow 27, introducing the liquid-phase material flow 27 and the recycle hydrogen into a hydrocracking pretreatment reactor 3, mixing the hydrocracking pretreatment material flow with the recycle hydrogen and entering the hydrocracking reactor 4, extracting a hydrocracking raw material flow 5 from a reactant flow passing through a first hydrocracking catalyst bed, introducing the material flow after extracting the hydrocracking raw material flow 5 into a subsequent hydrocracking catalyst bed, introducing a hydrocracking generated material flow 6 into a hydrocracking high-pressure separator 8 for gas-liquid separation, introducing a liquid obtained by separation into a fractionating tower 10 for fractionating to obtain a hydrocracking light naphtha product 12, Hydrocracking heavy naphtha product 14, hydrocracking aviation kerosene product 14, hydrocracking diesel oil product 15 and hydrocracking tail oil product 16, wherein a hydrocracking raw material flow 5 enters a hydroisomerization cracking reactor 7, a resultant flow passing through a hydrocracking catalyst bed enters a hydroisomerization cracking high-pressure separator 9 for gas-liquid separation, the liquid obtained by separation enters a fractionating tower 11 for fractionation to obtain a hydroisomerization cracking light naphtha product 17, a hydroisomerization cracking heavy naphtha product 18, a hydroisomerization cracking aviation kerosene product 19, a hydroisomerization cracking diesel oil product 20 and a hydroisomerization cracking tail oil product 21, the hydrocracking light naphtha product 12 and the hydroisomerization cracking light naphtha product 17 can be used as products independently or can be mixed to obtain a mixed light naphtha product, the hydrocracking heavy naphtha product 13 and the hydroisomerization heavy naphtha product 18 can be used as products independently, or mixed to obtain a mixed heavy naphtha product, the hydrocracking aviation kerosene product 14 and the hydroisomerization cracking aviation kerosene product 19 can be independently used as products or mixed to obtain a mixed aviation kerosene product, the hydrocracking diesel oil product 15 and the hydroisomerization cracking diesel oil product 20 can be independently used as products or mixed to obtain a mixed diesel oil product, the hydrogen-rich gas 22 obtained by the separation of the hydrocracking high-pressure separator 8, the hydrogen-rich gas 23 obtained by the separation of the hydroisomerization cracking high-pressure separator 9 and the hydrogen-rich gas 26 obtained by the separation of the hydrogenation pretreatment high-pressure separator 25 are mixed and then are pressurized by a recycle hydrogen compressor and mixed with make-up hydrogen 24 to be used as recycle hydrogen.

The embodiments and effects of the present invention are described below by way of examples.

Examples 1 to 3

The protective agents FZC-100, FZC-105 and FZC106 are hydrogenation protective agents developed and produced by the smooth petrochemical research institute of the China petrochemical industry, Inc.; the catalyst FZC-204 is a hydrodemetallization catalyst developed and produced by the smooth petrochemical research institute of China petrochemical company Limited; the catalyst FF-56 is a hydrotreating catalyst developed and produced by the smooth petrochemical research institute of China petrochemical company Limited; the catalyst FC-32 is a hydro-upgrading catalyst developed and produced by China petrochemical company Limited, compliant petrochemical research institute, and contains a Y-type molecular sieve; the catalyst FC-20 is a hydroisomerization cracking catalyst which is developed and produced by the smooth petrochemical research institute of China petrochemical company Limited and contains a beta-type molecular sieve.

TABLE 1 Primary Properties of shale oil base stocks

TABLE 2 Process conditions

Table 2 Process conditions

TABLE 3 test results

It can be seen from the examples that, the flexible shale oil hydrocracking process of the present invention realizes the purpose of producing hydrocracking products with different properties by using the hydrocracking pretreatment and the pretreatment to separate the generated material flow, extracting a part of the reaction material flow from the hydrocracking reactor, and using the hydrocracking catalyst and the hydroisomerization cracking catalyst, and the production mode is flexible.

Claims

1. A flexile shale oil hydrocracking process comprising the steps of:

b. b, allowing the liquid phase material flow obtained in the step a to enter a hydrocracking pretreatment reactor under a hydrocracking pretreatment condition and pass through a hydrocracking pretreatment catalyst bed layer, and allowing the hydrocracking pretreatment material flow to pass through a hydrocracking catalyst bed layer containing a Y-type molecular sieve catalyst on the upper part of the hydrocracking reactor under the hydrocracking condition to obtain a first hydrocracking material flow; this part of the reaction stream is divided into two parts, one of which is withdrawn from the hydrocracking reactor;

c. b, continuously passing the rest first hydrocracking material flow through a hydrocracking catalyst bed layer containing a Y-shaped molecular sieve catalyst at the lower part of the hydrocracking reactor under the hydrocracking condition, and separating and fractionating the hydrocracking material flow to obtain a hydrocracking high-pressure hydrogen-rich gas, a hydrocracking gas product, a hydrocracking naphtha product, a hydrocracking aviation kerosene product, a hydrocracking diesel oil product and a hydrocracking tail oil product;

2. The hydrocracking process of claim 1, further comprising step e: and d, mixing the hydrogenation pretreatment high-pressure hydrogen-rich gas obtained in the step a, the hydrocracking high-pressure hydrogen-rich gas obtained in the step c and the hydroisomerization cracking high-pressure hydrogen-rich gas obtained in the step d for recycling.

3. The hydrocracking process according to claim 1, wherein the shale oil feedstock of step a has an initial boiling point of 100 to 400 ℃ and an end boiling point of 405 to 650 ℃.

4. The hydrocracking process according to claim 2, wherein the shale oil feed oil further comprises one or more of coal tar, coal direct liquefaction oil, coal indirect liquefaction oil, synthetic oil, virgin wax oil, coker wax oil, and catalytic cycle oil.

5. The hydrocracking process according to claim 1, wherein the hydrotreating catalyst in step a and the hydrocracking pretreatment catalyst in step B both use group vib and/or group viii metals as active components and alumina or siliceous alumina as a carrier; based on the weight of the catalyst, the content of the VIB group metal is 10-35 wt% calculated by oxide, and the content of the VIII group metal is 3-15 wt% calculated by oxide; the properties are as follows: the specific surface area is 100 to 650m²The pore volume is 0.15 to 0.6 mL/g.

6. The hydrocracking process according to claim 1, wherein the hydrotreating pretreatment conditions in step a are: the reaction pressure is 3.0MPa to 19.0MPa, the reaction temperature is 260 ℃ to 430 ℃, and the liquid hourly volume space velocity is 0.2h^-1～6.0h^-1The volume ratio of the hydrogen to the oil is 100: 1-2000: 1.

7. The hydrocracking process according to claim 1, wherein said hydrotreating catalyst in step a is loaded with a hydrogenation protecting agent and a hydrodemetallization catalyst thereon; the hydrogenation protective agent accounts for 5-20% of the total catalyst volume of the hydrogenation pretreatment reactor, and the hydrogenation demetalization catalyst accounts for 10-40% of the total catalyst volume of the hydrogenation pretreatment reactor.

8. The hydrocracking process of claim 1, wherein the liquid stream in step a is free of water produced by the reaction or water introduced from the outside.

9. The hydrocracking process according to claim 1, characterized in that the total metal content in the liquid phase stream obtained in step a is not more than 5 μ g/g.

10. The hydrocracking process according to claim 1, wherein the hydrocracking pretreatment conditions in step b are: the reaction pressure is 3.0MPa to 19.0MPa, the reaction temperature is 300 ℃ to 450 ℃, and the liquid hourly volume space velocity is 0.2h^-1～6.0h^-1The volume ratio of the hydrogen to the oil is 100: 1-2000: 1.

11. The hydrocracking process according to claim 1, wherein the hydrocracking catalyst in steps B and c is prepared by using metals in group VIB and/or group VIII as active components, and the catalyst carrier contains one or more of alumina, siliceous alumina and Y-type molecular sieve; based on the weight of the catalyst, the content of the VIB group metal is 10-35 wt% calculated by oxide, the content of the VIII group metal is 3-15 wt% calculated by oxide, and the content of the molecular sieve is 5-80 wt%.

12. The hydrocracking process according to claim 1, wherein the hydrocracking conditions in step b are: the reaction pressure is 3.0MPa to 19.0MPa, the reaction temperature is 300 ℃ to 450 ℃, and the liquid hourly volume space velocity is 0.2h^-1～6.0h^-1The volume ratio of the hydrogen to the oil is 100: 1-2000: 1.

13. The hydrocracking process according to claim 1, wherein the partial stream withdrawn in step b is 5 to 95wt% based on the weight of the feedstock in liquid phase.

14. According to the claims1, the hydrocracking process is characterized in that the hydrocracking conditions in the step c are as follows: the reaction pressure is 3.0MPa to 19.0MPa, the reaction temperature is 300 ℃ to 450 ℃, and the liquid hourly volume space velocity is 0.2h^-1～6.0h^-1The volume ratio of the hydrogen to the oil is 100: 1-2000: 1.

15. The hydrocracking process according to claim 1, wherein the hydroisomerization catalyst of step d comprises a group VIB and/or group VIII metal as an active component, wherein the carrier of the catalyst comprises one or more of alumina, siliceous alumina and a molecular sieve, and the molecular sieve is a beta-type molecular sieve or a Sapo-type molecular sieve; based on the weight of the catalyst, the content of the VIB group metal is 10-35 wt% calculated by oxide, the content of the VIII group metal is 3-15 wt% calculated by oxide, and the content of the molecular sieve is 5-80 wt%.

16. The hydrocracking process according to claim 1, wherein said hydroisomerization cracking conditions are: the reaction pressure is 3.0MPa to 19.0MPa, the reaction temperature is 300 ℃ to 450 ℃, and the liquid hourly volume space velocity is 0.2h^-1～6.0h^-1The volume ratio of the hydrogen to the oil is 100: 1-2000: 1.

17. The hydrocracking process according to claim 1, wherein the partial stream withdrawn in step b is 10 to 80wt% based on the weight of the feedstock in liquid phase.