RU2708252C1 - Method and apparatus for hydrogenating waxy oil - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil processing. Method includes: (1) contact of paraffin oil as raw material and hydrogen-containing gas with first hydrotreating catalyst, separation of the first hydrotreated flow produced as a result of contact into two parts, i.e. first hydrotreated flow A and first hydrotreated flow B, and performing gas-liquid separation of first hydrotreated flow A to produce first hydrotreated gas-phase flow and first hydrotreated liquid-phase flow; (2) providing contact of first hydrotreated stream B, first hydrotreated liquid-phase flow and hydrogen-containing gas with second hydrotreating catalyst to obtain finished hydrotreated flow, and (3) contacting the first hydrotreated gas-phase flow and the light catalytic cracking recycle gas oil with the hydrofining catalyst for conducting the hydrotreating reaction to obtain the finished hydrotreated flow, wherein the catalytic cracking recycle gas oil initial boiling point is 100–200 °C, and the catalytic cracking recycle gas oil end boiling point temperature is 320–400 °C, first hydrotreated flow A is 5–95 wt% of total weight of first hydrotreated flow A and first hydrotreated flow B, hydroprocessed gas-phase flow makes 5–95 vol.% of hydrogen-containing gas at stage (1). Invention also relates to a version of the method and apparatus for hydrogenating paraffin oil.

EFFECT: obtaining high-quality raw materials for catalytic cracking and performing a technologically flexible process with low power consumption.

18 cl, 3 dwg, 6 tbl, 8 ex

Description

Technical field

The invention relates to the field of oil refining, in particular, to a method and apparatus for the hydrogenation of paraffin oil.

State of the art

Fluid-catalytic cracking (FCC) is one of the most important means to facilitate heavy fuel. However, as FKK raw materials deteriorate and become heavier, working conditions become more and more severe, and the yield and properties of light products are lower. FKK raw materials hydrotreating technologies not only allow removal of impurities such as sulfur, nitrogen, metal, etc., but can also improve the cracking performance of raw materials, soften the FKK operating conditions, improve product distribution, improve target product selectivity, reduce dry yield gas and coke, increase the economic efficiency of the FCC installation, reduce the sulfur content in the finished product and reduce the content of SOx and NOx in the regenerated exhaust gas, etc. Catalytic cracking light gas oil (LHG) has a certain sulfur and nitrogen content, which are contained in organic compounds, and a high content of aromatic hydrocarbons, in particular bicyclic and polycyclic aromatic hydrocarbons. LHG is usually recycled directly to the FCC unit for further processing or hydrogenated in a hydroprocessing unit and then returned to the FCC unit, or processed in other devices, or directly selected as a product.

CN 103773495 A, CN 101875856 A, CN 102465035 A and CN 1896192 A disclose a method for mixing light recycle catalytic cracked gas oil in the process of paraffin oil hydrotreatment, mainly to obtain high-quality FCC feedstock, or a complex method for circulating light catalytic cracked recycle gas oil between a unit hydrotreatment of paraffin oil and FKK plant for the implementation of clean production at the FKK plant. However, since paraffin oil is directly hydrogenated after it is mixed with light catalytic cracking gas oil, it is not possible to effectively control the degree of hydrogenation of catalytic cracking light gas oil; instead, it is necessary to use the sulfur content or nitrogen content in the mixed hydrogenation product (FCC feedstock) as a control indicator for control. This approach is not favorable for the effective regulation of the production of high-quality gasoline with light catalytic cracking gas oil.

Briefly, in existing technologies for hydrogenation of light recycle gas oil of catalytic cracking and hydrogenation of paraffin oil, usually light recycle gas oil of catalytic cracking is directly mixed in a hydroprocessing unit for hydrogenation, and hydrogenated paraffin oil and hydrogenated light recycle gas oil of catalytic cracking obtained from feedstock for a catalytic cracking unit, i.e. light recycle catalytic cracking gas oil is returned to the FCC unit after its hydrogenation. Since the degree of hydrogenation of light recycle gas oil for catalytic cracking is not strictly controlled, the quality of gasoline obtained during catalytic cracking is not the best; in addition, there is no combined processing technology for the combined reaction materials.

SUMMARY OF THE INVENTION In order to overcome the above disadvantages of the prior art, the present invention provides a method and apparatus for hydrogenating paraffin oil. In the present invention, paraffin oil and light catalytic cracking gas oil are treated by a combined hydrotreatment and hydrotreatment process to produce high quality FCC feedstock; in addition, the process is technologically flexible and energy consumption is low.

In order to achieve the above objective, in a first aspect of the present invention, there is provided a method for hydrogenating paraffin oil, which comprises the following steps:

(1) contacting the paraffinic oil as a feedstock and a hydrogen-containing gas with a first hydroprocessing catalyst under the conditions of the first hydroprocessing, dividing the first hydroprocessed stream resulting from the contact into two parts, i.e. the first hydrotreated stream A and the first hydrotreated stream B, and performing gas-liquid separation of the first hydrotreated stream A to obtain a first hydrotreated gas-phase stream and a first hydrotreated liquid-phase stream;

(2) providing contact of the first hydrotreated stream B, the first hydrotreated liquid phase stream and a hydrogen-containing gas with the second hydrotreatment catalyst under the conditions of the second hydrotreatment to obtain the finished hydrotreated stream, and

(3) contacting the first hydrotreated gas-phase stream and light catalytic cracking gas oil with a hydrotreating catalyst for carrying out a hydrotreating reaction under hydrotreating conditions to obtain a finished hydrotreated stream.

Preferably, the method further comprises separating the light recycle gas oil of catalytic cracking to obtain a light fraction and a heavy fraction, where the cut-off temperature is 245-300 ° C; stage (3) includes: contacting the first hydrotreated gas-phase stream, the heavy fraction and the hydrogen-containing gas with the first hydrotreating catalyst to provide a first hydrotreating reaction under the conditions of the first hydrotreating to obtain a first hydrotreated stream; then, contacting the first hydrotreated stream, light fraction and hydrogen-containing gas with the second hydrotreating catalyst, providing a second hydrotreating reaction under the conditions of the second hydrotreating. It is also preferred that the temperature of the second hydrotreatment reaction is lower than the temperature of the first hydrotreatment reaction; even more preferably, the temperature of the second hydrotreatment reaction is lower than the temperature of the first hydrotreatment reaction by 5-20 ° C (more preferably 10-20 ° C). In a preferred embodiment, the degree of hydrogenation of aromatic hydrocarbons can be better controlled to produce more monocyclic aromatic hydrocarbons, provided that sulfur requirements are met.

In a second aspect, the present invention provides a paraffin oil hydrogenation unit, comprising:

first hydroprocessing unit;

a gas-liquid separator designed to carry out gas-liquid separation of a portion of the first hydrotreated stream obtained in the first hydrotreatment unit to obtain a first hydrotreated gas-phase stream and a first hydrotreated liquid-phase stream;

a second hydroprocessing unit for performing a second hydroprocessing of the remaining part of the first hydroprocessing stream and the first hydroprocessing liquid phase stream to obtain a finished hydroprocessing stream;

a catalytic cracking light recycle gas oil feed unit for supplying a catalytic cracking light recycle gas oil, and

a hydrotreating unit for hydrotreating a light recycle gas oil of catalytic cracking supplied by a feed unit of a light recycle gas oil of catalytic cracking and a hydrotreated gas-phase stream to obtain a finished hydrotreated stream.

Preferably, the hydrotreating unit includes a first hydrotreating unit and a second hydrotreating unit, which are arranged in series; the installation further includes a distillation column for light catalytic cracking light gas oil, located between the first hydrotreating unit and the catalytic cracking light cycle gas oil supply unit, for separating the catalytic cracking light cycle gas oil supplied by the light catalytic cracking light cycle gas oil unit and fraction; the heavy fraction and the first hydrotreated gas phase stream are hydrotreated in a first hydrotreatment unit to obtain a first hydrotreated stream; the first hydrotreated stream and the light fraction are hydrotreated in a second hydrotreatment unit to obtain a finished hydrotreated stream.

Product quality requirements, environmental protection and process implementation, etc. impose restrictions on the properties of raw materials for the installation of FCC, especially restrictions on the sulfur content. Moreover, the distribution and properties of FCC products vary widely due to the different composition of the feed. As a result of the studies, the author of the present invention found that the degree of hydrogenation of aromatic compounds of light recycle gas oil of catalytic cracking has a great influence on the quality of FCC gasoline. In particular, monocyclic aromatic hydrocarbons in gasoline are a high octane component, and the octane number of FCC gasoline can be increased due to an increase in the content of monocyclic aromatic hydrocarbons in the hydrogenated light catalytic cracking gas oil. As a result of further studies, the author of the present invention found that the content of monocyclic aromatic hydrocarbons in the subsequent product can be increased by extracting the gas phase stream from part of the first hydrotreated stream, possibly because the extracted gas phase stream contains hydrogen sulfide and ammonia in a certain concentration and has an inhibitory effect, equivalent to a decrease in catalyst activity. Thus, under hydrotreating conditions, the degree of hydrogenation of catalytic cracking light cycle gas oil can be controlled with high accuracy, and bicyclic aromatic hydrocarbons and polycyclic aromatic hydrocarbons in catalytic cracking light cycle gas oil can be hydrogenated to form monocyclic aromatic hydrocarbons, provided that the sulfur content requirements are met, unlike excessive hydrogenation to produce naphthenic hydrocarbons or incomplete hydrogen Hovhan to give the bicyclic aromatic hydrocarbons. Thus, when the hydrotreated product is returned to the FCC unit, the aromatic hydrocarbon content of the FCC gasoline can be increased, and thus, the octane number of the FCC gasoline can be increased. In addition, the method provided in the present invention reduces the adverse effect of hydrogen sulfide and ammonia on the second hydroprocessing catalyst and is more favorable for increasing the service life of the second hydroprocessing catalyst.

Compared with the prior art, the method and apparatus for the hydrogenation of paraffinic oil provided in the present invention have the following advantages.

1. In the present invention, at least two hydrotreating steps are carried out and a gas-liquid separation and retrieving part of the hydrotreated gas-phase stream is carried out between the two hydrotreatment steps to realize the efficient distribution of the hydrotreated streams, then the resulting streams are processed by a combined hydrogenation process so that finished products can be obtained with various parameters as required. In contrast, in the prior art, a hydrotreating method and a hydrotreating method are used separately, and therefore, usually only one hydrogenated finished product can be obtained.

2. In the present invention, gas-liquid separation is carried out between the two hydrotreating stages, the hydrotreated gas-phase stream obtained by hydrotreating the paraffinic oil is recovered, mixed with light catalytic cracking gas oil and the resulting mixture is fed for a separate hydrotreatment reaction. Since the recovered gas phase stream contains hydrogen sulfide and ammonia, it negatively affects the hydrodesulfurization reaction of easily recycle catalytic cracking gas oil and has an inhibitory effect, which is equivalent to a decrease in the activity of the catalyst. Under hydrotreating conditions, the degree of hydrotreating the light recycle gas oil of catalytic cracking is precisely controlled, and bicyclic aromatic hydrocarbons and polycyclic aromatic hydrocarbons in light recycle gas oil of catalytic cracking are hydrogenated to form monocyclic aromatic hydrocarbons, provided that they meet the sulfur content requirements, as opposed to excessive hydrogenation with hydrocarbons or incomplete hydrogenation to produce bicyclic aromatic hydrocarbons. Thus, when the hydrotreated product is returned to the FCC unit, the aromatic hydrocarbon content of the FCC gasoline can be increased, and thereby the octane number of the FCC gasoline can be increased; as for the hydrotreated part, since the hydrogen sulfide and ammonia components obtained by hydrodesulfurization and hydrodenitrification reactions during the first hydrotreatment are recovered, and the remaining stream is mixed with hydrogen-containing gas, which is equivalent to a decrease in the partial pressure of hydrogen sulfide and the partial pressure of ammonia during the second hydrotreatment, i.e. . reducing the inhibition of active centers of the subsequent hydroprocessing catalyst or increasing the activity of the second hydroprocessing catalyst and mitigating the conditions of the second hydroprocessing operation.

3. In the present invention, the gas-phase stream recovered between the two hydrotreating stages has a high temperature and high pressure, and can be mixed with a light recycle catalytic cracking gas oil after heat exchange and then directly provide a separate hydrotreating reaction; in this way, the heat generated by the hydrotreated gas phase stream can be completely utilized to carry out the combined hydrotreatment and hydrotreatment process.

4. In the present invention, the working pressure of the hydrotreatment reaction system and the working pressure of the hydrotreatment reaction system can be the same, and one separation and fractionation unit can be used for the hydrotreatment reaction system and the hydrotreatment reaction system; thus, equipment and operating costs can be significantly reduced.

Brief Description of the Drawings

In FIG. 1 is a block diagram of a paraffin oil hydrogenation unit provided in Example 1 of the present invention;

in FIG. 2 is a block diagram of a paraffin oil hydrogenation unit provided in Example 4 of the present invention;

In FIG. 3 is a block diagram of a paraffin oil hydrogenation unit provided in Example 5 of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

Endpoints and any value in the ranges disclosed in the present invention are not limited to the exact ranges and values; instead, these ranges or values should be understood as encompassing values close to these ranges or values. For numerical ranges, the endpoints of the ranges and discrete values can be combined with each other to produce one or more new numerical ranges, which should be considered specifically disclosed herein.

In a first aspect of the present invention, there is provided a method for hydrogenating paraffinic oil, comprising the following steps:

(1) contacting the paraffinic oil as a feedstock and a hydrogen-containing gas with a first hydroprocessing catalyst under the conditions of the first hydroprocessing, dividing the first hydroprocessed stream resulting from the contact into two parts, i.e. the first hydrotreated stream A and the first hydrotreated stream B and gas-liquid separation of the first hydrotreated stream A to obtain a first hydrotreated gas-phase stream and a first hydrotreated liquid-phase stream;

(2) providing contact of the first hydrotreated stream B, the first hydrotreated liquid phase stream and a hydrogen-containing gas with a second hydrotreatment catalyst under the conditions of the second hydrotreatment to obtain a finished hydrotreated stream, and

(3) contacting the first hydrotreated gas phase stream and light catalytic cracking gas oil with a hydrotreating catalyst, providing a hydrotreating reaction under hydrotreating conditions to obtain a finished hydrotreated stream.

In accordance with the present invention, preferably the initial boiling point of paraffin oil is 100-400 ° C, and the final boiling point of paraffin oil is 405-650 ° C. For example, the initial boiling point of paraffin oil is 320-345 ° C, and the final boiling point of paraffin oil is 550-620 ° C.

Paraffin oil can be selected from at least one material from vacuum gas oil (VGO), heavy catalytic cracking gas oil (THCK), deasphalted oil (DAN), coal tar, a product of direct distillation of coal (PPSU), a product of distillation of indirect liquefaction of coal ( PKSU), synthetic oil and oil from tar shale.

Hydrogen-containing gas refers to a gas that supplies hydrogen, and may be fresh hydrogen, recycled hydrogen, or a hydrogen-rich gas. The hydrogen-containing gas in step (1) and the hydrogen-containing gas in step (2) in the present invention may be the same or different. Those skilled in the art will appreciate what hydrogen-containing gas means in the present invention after reading the technical scheme of the present invention.

In accordance with the present invention, the first hydroprocessing catalyst and the second hydroprocessing catalyst may be various hydroprocessing catalysts that are conventionally used in the art; preferably, the first hydroprocessing catalyst and the second hydroprocessing catalyst contain a carrier and an active component, respectively and independently, where the active component is selected from at least one metal element of group VIB and / or VIII, and the carrier is alumina and / or silicon-containing alumina. The metal element of group VIB is usually Mo and / or W, and the metal element of group VIII is usually Co and / or Ni.

Preferably, based on the total mass of the catalyst for the first hydroprocessing and in terms of oxide, the content of the metal element of the VIB group is 10-35 mass. %, and the content of the metal element of group VIII is 3-15 mass. % Also preferably, the specific surface area of the first hydroprocessing catalyst is 100-650 m ² / g, and the pore volume of the first hydroprocessing catalyst is 0.15-0.6 ml / g.

Preferably, based on the total weight of the catalyst for the second hydroprocessing and in terms of oxide, the content of the metal element of the VIB group is 10-35 mass. %, and the content of the metal element of group VIII is 3-15 mass. % Also preferably, the specific surface area of the second hydroprocessing catalyst is 100-650 m ² / g, and the pore volume of the second hydroprocessing catalyst is 0.15-0.6 ml / g.

The first hydroprocessing catalyst and the second hydroprocessing catalyst can be purchased or obtained. The first hydroprocessing catalyst and the second hydroprocessing catalyst in the present invention respectively and independently include, but are not limited to, hydroprocessing catalysts 3936, 3996, FF-16, FF-24, FF-26, FF-36, FF-46 and FF-56, manufactured by Sinopec Dalian (Fushun) Research Institute of Petroleum and Petrochemicals, HC-K and HC-P catalysts manufactured by UOP, TK-555 and TK-565 catalysts manufactured by Topsoe, and KF-847 and KF-848 catalysts manufactured by Akzo. The first hydroprocessing catalyst and the second hydroprocessing catalyst in the present invention may be the same or different.

The conditions of the first hydroprocessing and the conditions of the second hydroprocessing may be traditional operating conditions. For example, the conditions of the first hydrotreatment and the conditions of the second hydrotreatment respectively and independently include: reaction pressure of 3-19 MPa, reaction temperature of 300-450 ° C, hourly volumetric rate of liquid 0.2-6 h ^-1 and volumetric ratio of hydrogen to oil: 100- 2000: 1; preferably, the conditions of the first hydroprocessing and the conditions of the second hydroprocessing, respectively and independently, include: a reaction pressure of 4-17 MPa; the reaction temperature is 320-420 ° C, the hourly volumetric rate of the liquid is 0.4-4 h ^-1 and the volumetric ratio of hydrogen to oil is 400-1500: 1, more preferably the conditions of the first hydrotreatment and the conditions of the second hydrotreatment, respectively, and independently include: reaction pressure 6- 17 MPa; the reaction temperature is 350-385 ° C, the hourly volumetric rate of the liquid is 0.8-4 h ^-1 and the volumetric ratio of hydrogen to oil: 700-1500: 1. The conditions of the first hydroprocessing and the conditions of the second hydroprocessing can be the same or different.

According to the present invention, for better protection of the first hydroprocessing catalyst, preferably the method further comprises contacting the paraffin oil with a protective hydroprocessing catalyst and then contacting the first hydroprocessing catalyst. Such a preferred embodiment is more favorable for extending the life of the first hydroprocessing catalyst. More specifically, a hydroprocessing protective catalyst may be charged over the first hydroprocessing catalyst layer. There are no particular requirements for the protective hydroprocessing catalyst of the present invention. In other words, the hydroprocessing protective catalyst can be any hydroprocessing protective catalyst that is traditionally used in technology, such as the FZC series catalysts developed by Sinopec Dalian (Fushun) Research Institute of Petroleum and Petrochemicals, including FZC-100, FZC-105 and FZC- 106. To improve the effect of the protective hydroprocessing catalyst, two or more protective hydroprocessing catalysts mixed together may be used as the protective hydroprocessing catalyst. One of ordinary skill in the art can select a protective hydroprocessing catalyst in accordance with the actual conditions.

In accordance with the present invention, the operating conditions of the protective hydroprocessing catalyst may be conventional operating conditions. For example, the reaction pressure can be 3-19 MPa, the reaction temperature can be 280-420 ° C, the hourly space velocity of the liquid can be 0.5-20 h ^-1 and the volumetric ratio of hydrogen to oil can be 100-2000: 1.

In accordance with a preferred embodiment of the present invention, the share of the first hydrotreated stream And accounts for 5-95 mass. % of the total mass of the first hydrotreated stream A and feather hydrotreated stream B, more preferably 10-80 mass. %, even more preferably 22-53 mass. %

In accordance with the present invention, gas-liquid separation of the first hydrotreated stream A can be performed in a gas-liquid separator. Gas-liquid separation conditions are not particularly limited in the present invention. In other words, gas-liquid separation can be performed using traditional technical means. The gas-liquid separator at least includes a reagent inlet, a liquid phase conduit and a gas phase conduit. More specifically, the first hydrotreated gas-phase stream obtained by separation is recovered through the gas phase conduit, and the first hydroprocessed gas-phase stream obtained by separation is sent through the liquid phase conduit to the unit for the second hydrotreatment reaction.

In accordance with a preferred embodiment of the present invention, the hydrotreated gas phase stream is 5-95 vol. % hydrogen-containing gas in stage (1), preferably 10-80 vol. %, more preferably 20-50 vol. %

In accordance with the present invention, light recycle gas oil (LHG) catalytic cracking is not particularly limited. In other words, the light catalytic cracking gas oil can be any light catalytic cracking gas oil traditionally used in the art. For example, the initial boiling point of light recycle gas oil of catalytic cracking is 100-200 ° C, and the final boiling point of light recycle gas oil of catalytic cracking is 320-400 ° C. Examples of the present invention are described by the example of light recycle gas oil of catalytic cracking with a boiling range of a fraction of 156-380 ° C.

In accordance with the method described in the present invention, the light catalytic cracking gas oil may also contain at least one coking light gas oil, ethylene cracking resin and coal tar material. This embodiment allows you to expand the sources of raw materials for diesel fuel, which contain a large amount of aromatic hydrocarbons.

In accordance with the method provided in the present invention, preferably the mass ratio of light recycle catalytic cracking gas oil to paraffinic oil is 0.1-3: 1, more preferably 0.3-1.1: 1.

In accordance with the present invention, the hydrotreating catalyst may be any hydrotreating catalyst conventionally used in the art. Preferably, the hydrotreating catalyst comprises a support and an active component, wherein the active component is selected from at least one of a group VIB and / or Group VIII metal element and the support is alumina and / or silicon-containing alumina. The metal element of group VIB is usually Mo and / or W, and the metal element of group VIII is usually Co and / or Ni. Preferably, based on the total weight of the hydrotreating catalyst and in terms of oxide, the content of the metal element of the VIB group is 10-35 mass. %, and the content of the metal element of group VIII is 3-15 mass. % Also preferably, the specific surface area of the hydrotreating catalyst is 100-650 m ² / g, and the pore volume of the hydrotreating catalyst is 0.15-0.6 ml / g.

A hydrotreating catalyst may be purchased or obtained. The hydrotreating catalyst in the present invention includes, but is not limited to, catalysts 3936, FF-14, FF-16, FF-24, FF-26, FF-36, FF-56, FHUDS-5 and FHUDS-7, developed by Sinopec Dalian (Fushun) Research Institute of Petroleum and Petrochemicals, HC-K and HC-P catalysts manufactured by UOP, TK-555 and TK-565 catalysts manufactured by Topsoe, and KF-847 and KF-848 catalysts manufactured by Akzo.

In accordance with the present invention, hydrotreating conditions may include a reaction pressure of 3-19 MPa, a reaction temperature of 260-450 ° C., a liquid hourly space velocity of 0.2-6 h-1, a volumetric ratio of hydrogen to oil of 100-2000: 1, and preferably the reaction temperature is 280-410 ° C; also preferably, hydrotreating conditions include: a reaction pressure of 4-17 MPa, a reaction temperature of 300-400 ° C., a liquid hourly space velocity of 0.5-5 h ^-1 and a hydrogen to oil volume ratio of 300-1,500: 1, even more preferably hydrotreating conditions include: a reaction pressure of 6-17 MPa, a reaction temperature of 340-375 ° C., a hourly volumetric rate of liquid of 1.5-5 h ^-1 and a volumetric ratio of hydrogen to oil of 1000-1500: 1.

According to a preferred embodiment of the present invention, the method further comprises separating the light recycle gas oil of catalytic cracking to obtain a light fraction and a heavy fraction, wherein the cut-off temperature is 245-300 ° C, more preferably 260-280 ° C; stage (3) includes contacting the first hydrotreated gas-phase stream, the heavy fraction and the hydrogen-containing gas with the first hydrotreating catalyst to conduct the first hydrotreating reaction under the conditions of the first hydrotreating to obtain a first hydrotreated stream; then contacting the first hydrotreated stream, light fraction and hydrogen-containing gas with a second hydrotreating catalyst for conducting a second hydrotreating reaction under conditions of a second hydrotreating.

Even more preferably, the temperature of the second hydrotreatment reaction is lower than the temperature of the first hydrotreatment reaction; preferably, the temperature of the second hydrotreatment reaction is lower than the temperature of the first hydrotreatment reaction by 5-20 ° C; more preferably, the temperature of the second hydrotreatment reaction is lower than the temperature of the first hydrotreatment reaction by 10-20 ° C.

The heavy fraction obtained by separating the starting light recycle gas oil of catalytic cracking is mainly polycyclic aromatic hydrocarbons, which are subjected to hydrotreating reactions twice, and they are more favorable to achieve the goal of controlling the degree of hydrogenation of aromatic compounds; bicyclic aromatic hydrocarbons in the light fraction obtained by separation of light recycle gas oil of catalytic cracking are subjected to a less intense (single) hydrotreatment reaction, and they can be used with a heavy fraction of light recycle gas oil of catalytic cracking to further achieve the goal of controlling the degree of hydrogenation of aromatic compounds; namely, bicyclic aromatic hydrocarbons and polycyclic aromatic hydrocarbons in hydrotreated light cycle gas oil of catalytic cracking are moderately hydrogenated to form monocyclic aromatic compounds, provided that they meet the sulfur content requirements, and monocyclic aromatic compounds are additionally treated with porous chemistry of FCC to produce catalytic gasoline that meets the requirements for catalytic gasoline sulfur content and has an improved octane rating.

In addition, in a preferred embodiment of the present invention, the temperature of the second hydrotreatment reaction is lower than the temperature of the first hydrotreatment reaction by 5-20 ° C (more preferably 10-20 ° C) and is more favorable for the hydrosaturation of bicyclic aromatic hydrocarbons with the formation of monocyclic aromatic hydrocarbons .

According to a preferred embodiment of the present invention, the conditions of the first hydrotreatment and the conditions of the second hydrotreatment respectively and independently include: a reaction pressure of 4-17 MPa, a reaction temperature of 300-400 ° C., a hourly volumetric flow rate of 0.5-5 h ^-1 and a volumetric ratio hydrogen to oil 300-1500: 1; preferably, the conditions of the first hydrotreating and the conditions of the second hydrotreating respectively and independently include: reaction pressure of 6-17 MPa, reaction temperature of 340-385 ° C, hourly volumetric rate of liquid 1.5-5 h ^-1 and volumetric ratio of hydrogen to oil 1000-1500 :one.

Preferably, the temperature of the first hydrotreatment reaction is 340-395 ° C, and the temperature of the second hydrotreatment reaction is 320-385 ° C, more preferably the temperature of the first hydrotreatment reaction is 355-375 ° C, and the temperature of the second hydrotreatment reaction is 340-365 ° C.

It is also preferable that the hourly volumetric flow rate of the liquid of the first hydrotreating reaction is 0.5-5.0 h ^-1 (preferably 1.0-4.0 h ^-1 , more preferably 1.5-2.1 h ^-1 ), and hourly the fluid volumetric rate of the second hydrotreating reaction is 1.0-6.0 h ^-1 (preferably 1.5-5.0 h ^-1 , more preferably 3.3-4.5 h ^-1 ).

In accordance with the present invention, the first hydrotreatment in step (1) and the second hydrotreatment in step (2) can be performed in one hydrogenation reactor or in two hydrogenation reactors. In particular, if the first hydroprocessing in step (1) and the second hydroprocessing in step (2) are carried out in one hydrogenation reactor, the catalyst bed of the first hydroprocessing and the catalyst layer of the second hydroprocessing are arranged sequentially in the hydrogenation reactor, and a gas-liquid separator can be located between the catalyst layer of the first hydrotreatment and a catalyst bed of the second hydrotreatment for gas-liquid separation. If the hydroprocessing in step (1) and the second hydroprocessing in step (2) are carried out in two reactors, the first hydroprocessing in step (1) can be performed in the first hydroprocessing reactor, and the second hydroprocessing in step (2) can be performed in the second hydroprocessing reactor, the first hydroprocessing reactor and the second hydroprocessing reactor are arranged in series, and gas-liquid can be located between the first hydroprocessing reactor and the second hydroprocessing reactor for gas-liquid separation.

According to the present invention, the hydrotreating step (3) can be carried out in a hydrotreating reactor in which a hydrotreating catalyst layer is provided. Moreover, preferably the hydrotreatment reaction in step (3) comprises a first hydrotreatment reaction and a second hydrotreatment reaction. The first hydrotreating reaction and the second hydrotreating reaction can be performed in one hydrogenation reactor or two hydrogenation reactors. In particular, if the first hydrotreating reaction and the second hydrotreating reaction are carried out in one hydrogenation reactor, the catalyst bed of the first hydrotreating and the catalyst layer of the second hydrotreating are arranged sequentially in the hydrogenation reactor. If the first hydrotreating reaction and the second hydrotreating reaction are carried out in two hydrogenation reactors, the first hydrotreating reaction can be performed in the first hydrotreating reactor, the second hydrotreating reaction can be performed in the second hydrotreating reactor, and the first hydrotreating reactor and the second hydrotreating reactor are arranged in series.

In accordance with the method provided in the present invention, a person skilled in the art can perform separation and fractionation for the finished hydrotreated stream obtained in stage (2) and the finished hydrotreated stream obtained in stage (3) in accordance with specific requirements to obtain specific products.

According to the method provided in the present invention, preferably step (2) further comprises treating the finished hydrotreated stream by separation and fractionation to obtain a hydrotreated hydrogen-rich gas, hydrotreated gas,

hydrotreated naphtha, hydrotreated diesel, and hydrotreated heavy fraction; more preferably, the separation in step (2) includes high pressure separation and low pressure separation, the finished hydrotreated stream is processed by high pressure separation to obtain a hydrotreated hydrogen rich gas and hydrotreated high pressure separated liquid phase stream, and then hydrotreated separated high pressure liquid phase stream processed by low pressure separation to obtain hydrotreated gas and hydrotreated liquid phase according to eye, and hydrotreated liquid-phase stream is fractionated to obtain a hydrotreated naphtha, hydrotreated diesel, and hydrotreated heavy fraction. High pressure separation may be performed in a high pressure separator, and low pressure separation may be performed in a low pressure separator. High pressure separation conditions and low pressure separation conditions are not particularly limited in the present invention. In other words, high pressure separation and low pressure separation can be carried out using traditional technical means.

One of skill in the art can perform fractionation specifically for a hydrotreated liquid phase stream in accordance with specific product requirements. The fractionation in step (2) in the present invention can be carried out in a hydrotreatment distillation column and the fractionation conditions in step (2) are not particularly limited in the case where the above products can be obtained. For example, the above products can be obtained by fractionation, in which the initial boiling point of hydrotreated naphtha can be 35-45 ° C, the cut-off temperature between hydrotreated naphtha and hydrotreated diesel fuel can be 60-180 ° C, and the cut-off temperature between hydrotreated diesel fuel and hydrotreated with a heavy fraction may be 330-375 ° C.

According to the method provided in the present invention, preferably step (3) further comprises treating the finished hydrotreated stream by separation and fractionation to obtain hydrotreated hydrogen rich gas, hydrotreated gas, hydrotreated naphtha and hydrotreated diesel fuel; more preferably, the separation in step (3) includes high pressure separation and low pressure separation, the obtained hydrotreated stream is treated by high pressure separation to obtain a hydrotreated hydrogen rich gas and hydrotreated high pressure separated liquid phase stream, and then the hydrotreated separated high pressure liquid phase stream is treated by low pressure separation to obtain hydrotreated gas and hydrotreated liquid phase stream, and hydrotreated nny liquid phase stream is processed by fractionation to obtain a hydrotreated naphtha, and hydrotreated diesel. High pressure separation may be performed in a high pressure separator, and low pressure separation may be performed in a low pressure separator. High pressure separation conditions and low pressure separation conditions are not particularly limited in the present invention. In other words, high pressure separation and low pressure separation can be carried out using traditional technical means.

One of skill in the art can perform fractionation specifically for a hydrotreated liquid phase stream in accordance with specific product requirements. The fractionation in step (3) in the present invention can be carried out in a hydrotreating distillation column, and the fractionation conditions in step (3) are not particularly limited in the case where the above products can be obtained. For example, the above products can be obtained by fractionation, where the initial boiling point of hydrotreated naphtha can be 35-45 ° C, and the cut-off temperature between hydrotreated naphtha and hydrotreated diesel fuel can be 60-180 ° C.

In the present invention, both hydrotreated gas and hydrotreated gas are hydrocarbon-rich gases. In addition, the gases can be separated according to actual requirements to produce the desired gaseous products.

According to a preferred embodiment of the present invention, the method further comprises recycling the hydrotreated hydrogen rich gas and the hydrotreated hydrogen rich gas to provide the desired hydrogen-containing gas. Hydrotreated hydrogen rich gas and hydrotreated hydrogen rich gas can be recycled directly or recycled after desulfurization.

The hydrotreated hydrogen rich gas and the hydrotreated hydrogen rich gas can be respectively recycled and reused independently in step (1) and / or step (2); in addition, fresh hydrogen may be introduced if the hydrotreated hydrogen rich gas and hydrotreated hydrogen rich gas are not sufficient to produce the hydrogen required by the process provided in the present invention. One of skill in the art can clearly understand how to recycle a hydrotreated hydrogen rich gas and a hydrotreated hydrogen rich gas after studying the flow chart of the present invention.

The concentration of hydrogen in the hydrotreated hydrogen-rich gas and hydrotreated hydrogen-rich gas is high, and the concentration of the hydrogen-containing gas is high and can usually reach 85-97 vol. % after hydrotreated hydrogen-rich gas and hydrotreated hydrogen-rich gas are mixed with fresh hydrogen.

To further simplify the installation, preferably hydrotreated hydrogen-rich gas and hydrotreated hydrogen-rich gas obtained by high pressure separation in step (1) and high pressure separation in step (2) are under the same pressure. In this preferred embodiment, the hydrotreated hydrogen rich gas and the hydrotreated hydrogen rich gas can be recycled using a single system.

The hydrotreated gas obtained in step (2) and the hydrotreated gas obtained in step (3) can be selected as separate products or can be mixed to produce a mixed gaseous product.

The hydrotreated naphtha obtained in step (2) and the hydrotreated naphtha obtained in step (3) may be selected as separate products or may be mixed to form a mixed naphtha product.

Hydrotreated diesel fuel obtained in stage (2) and hydrotreated diesel fuel obtained in stage (3) can be selected as separate products or can be mixed to obtain a mixed product - diesel fuel.

The hydrotreated heavy fraction obtained in stage (2) can be used as raw material for the FCC installation.

In accordance with the present invention, to further save equipment and operating costs, preferably the method further comprises mixing the finished hydrotreated stream and the finished hydrotreated stream to produce a mixed stream and then performing separation (preferably including high pressure separation and low pressure separation) and mixed fractionation flow; more preferably, the mixed stream is separated by high pressure separation to obtain a mixed hydrogen-rich gas and a mixed high-pressure separated liquid phase stream, and then the mixed high-pressure separated liquid-phase stream is separated by low pressure separation to obtain a mixed gas and a mixed liquid phase, and a mixed liquid phase the stream is fractionated to obtain a mixed naphtha, a mixed diesel fuel and a mixed heavy fraction. High pressure separation may be performed in a high pressure separator, and low pressure separation may be performed in a low pressure separator. High pressure separation conditions and low pressure separation conditions are not particularly limited in the present invention. In other words, high pressure separation and low pressure separation can be performed using conventional technical means.

One of skill in the art can fractionate specifically for a mixed liquid phase stream in accordance with specific product requirements. Fractionation can be performed in a mixing distillation column and the fractionation conditions are not particularly limited in the present invention in the case where the above products can be obtained. For example, the initial boiling point of the mixed naphtha may be 35-45 ° C, the cut-off temperature between the mixed naphtha and mixed diesel fuel may be 60-180 ° C, and the cut-off temperature between the mixed diesel fuel and the mixed heavy fraction may be 330-375 ° C .

Mixed gas is a hydrocarbon-rich gas. In addition, the gas can be separated according to actual requirements to produce the desired gaseous products.

According to a preferred embodiment of the present invention, the method further comprises recirculating the mixed hydrogen-rich gas to provide the desired hydrogen-containing gas. The mixed hydrogen rich gas may be recycled directly or may be recycled after desulfurization.

In a second aspect, the present invention provides a paraffin oil hydrogenation unit. As shown in FIG. 1, 2 and 3, the installation of hydrogenation of paraffin oil includes:

first hydroprocessing unit 1;

a gas-liquid separator 2, designed to carry out gas-liquid separation of a portion of the first hydrotreated stream obtained in the first hydroprocessing unit 1 to obtain a first hydrotreated gas-phase stream and a first hydrotreated liquid-phase stream;

a second hydroprocessing unit 3, intended for performing therein a second hydroprocessing of the remaining part of the first hydroprocessing stream and the first hydroprocessing liquid phase stream to obtain a finished hydroprocessing stream;

a catalytic cracking light recycle gas oil supply unit 4 for catalytic cracking light recycling gas oil, and

a hydrotreating unit 5 for hydrotreating a light recycle gas oil of catalytic cracking supplied by a light recycle gas oil of catalytic cracking unit 4 and a hydrotreated gas-phase stream to obtain a finished hydrotreated stream.

In the present invention, the catalytic cracking light recycle gas oil supply unit 4 is not particularly limited so long as it can provide catalytic cracking light recycle gas oil. The catalytic cracking light recycle gas oil feed unit 4 may be a storage tank for catalytic cracking light recycle gas oil or a device for producing catalytic cracking light recycle gas oil.

According to the present invention, the output of the catalytic cracking light recycle gas oil supply unit 4 is connected to the inlet of the hydrotreating unit 5 by means of a pipeline.

According to the apparatus provided in the present invention, preferably the gas-liquid separator 2 includes a reagent inlet, a liquid phase conduit and a gas phase conduit; the reagent inlet of the gas-liquid separator 2 is connected to the outlet of the first hydroprocessing unit 1, the hydroprocessed liquid-phase stream is sent to the second hydroprocessing unit 3 through the liquid phase pipeline, and the first hydroprocessed gas-phase stream is sent to the hydrotreating unit 5 through the gas phase pipeline. A portion of the first hydrotreated stream obtained in the first hydroprocessing unit 1 is treated by gas-liquid separation in a gas-liquid separator 2 to obtain a first hydrotreated gas-phase stream and a first hydrotreated liquid-phase stream; the first hydrotreated liquid-phase stream is fed through the pipeline for the liquid phase to the second hydrotreatment unit and processed together with the remaining part of the first hydrotreated stream by the second hydrotreatment in the second hydrotreatment unit 3; the first hydrotreated gas-phase stream is directed through the gas phase conduit to the hydrotreating unit 5 and processed together with the light catalytic cracking gas oil recirculated by the catalytic cracking light recycle gas oil supply unit 4 by hydrotreating in the hydrotreating unit 5.

In accordance with the installation provided in the present invention, the placement of the first hydroprocessing unit 1 and the second hydroprocessing unit 3 are not particularly limited. According to an embodiment of the present invention, the first hydroprocessing unit 1 and the second hydroprocessing unit 3 may be located in one hydrogenation reactor; in accordance with another embodiment of the present invention, the first hydroprocessing unit 1 and the second hydroprocessing unit 3 can be located in different hydrogenation reactors, respectively.

In a preferred embodiment of the present invention, the hydrotreating unit 5 includes a first hydrotreating unit 51 and a second hydrotreating unit 52, which are arranged in series, and the installation further includes a distillation column 12 for light catalytic cracking gas oil located between the first hydrotreating unit 51 and the light recycling gas oil supply unit 4 catalytic cracking for separating light recycle gas oil of catalytic cracking fed through a light retse feed unit catalytic cracking gas oil, to light fraction and heavy fraction; the heavy fraction and the first hydrotreated gas phase stream are hydrotreated in the first hydrotreatment unit 51 to produce a first hydrotreated stream; the first hydrotreated stream and the light fraction are hydrotreated in a second hydrotreatment unit 52 to produce a finished hydrotreated stream.

More specifically, the inlet of the distillation column 12 for light catalytic cracking gas oil is connected to the inlet of the catalytic cracking light gas oil supply unit 4 through a pipe, wherein the light catalytic cracking gas oil circulating through the catalytic cracking light gas oil supply unit 4 is fed to the distillation unit 12 for light recycle gas oil catalytic cracking and there is fractionated to obtain a light fraction and a heavy fraction. The distillation column 12 for light recycle gas oil of catalytic cracking contains an outlet for a light fraction and an exit for a heavy fraction, while the output for a heavy fraction of a distillation column 12 for light recycle gas oil of a catalytic cracking is connected to the inlet of the first hydrotreating unit 51, and the output for a light fraction of a distillation column 12 for light recycle catalytic cracking gas oil is connected to the inlet of the second hydrotreating unit 52.

According to the present invention, the first hydrotreating unit 51 and the second hydrotreating unit 52 can be located in the same hydrogenation reactor or in different hydrogenation reactors, respectively. Preferably, the first hydrotreating unit 51 and the second hydrotreating unit 52 are located in one hydrogenation reactor.

According to a preferred embodiment, the bicyclic aromatic hydrocarbons and polycyclic aromatic hydrocarbons in the light catalytic cracking gas oil can be more easily moderated with hydrogen to form monocyclic aromatic hydrocarbons, subject to sulfur requirements, and then monocyclic aromatic hydrocarbons can be further processed by catalytic cracking to produce FKK gasoline, which meets the requirements for w sulfur and has an improved octane number.

According to the apparatus provided in the present invention, one skilled in the art can separate and fractionate the finished hydrotreated stream obtained in the second hydrotreatment unit 3 and the finished hydrotreated stream obtained in the hydrotreatment unit 5, in accordance with specific requirements, to obtain specific products.

According to an embodiment of the present invention, the finished hydrotreated stream and the finished hydrotreated stream are treated by separation and fractionation, respectively.

Preferably, the installation provided in the present invention further includes:

a hydroprocessing separator unit including a hydroprocessing high pressure separator 61 and a hydroprocessing low pressure separator 62 connected in series, where the output of the second hydroprocessing unit 3 is connected to the inlet of the hydroprocessing high pressure separator 61 through a pipeline; the finished hydrotreated stream is separated at high pressure in a high-pressure hydroprocessing separator 61 to obtain a hydrotreated hydrogen-rich gas and a hydrotreated high-pressure separated liquid phase stream, and then the hydrotreated high-pressure separated liquid-phase stream is separated at low pressure in a low-pressure hydrotreated separator 62 to obtain a hydrotreated gas and hydrotreated liquid phase flow.

Preferably, the apparatus provided in the present invention further includes a hydroprocessing distillation column 7 in which the inlet of the hydroprocessing distillation column 7 is connected to the outlet of the low pressure hydroprocessing separator 62 through a pipeline, the hydroprocessed liquid phase stream being fractionated in the hydroprocessing distillation column 7 to produce a hydrotreated naphtha, hydrotreated diesel fuel and hydrotreated heavy fraction.

Preferably, the apparatus provided in the present invention also includes a hydrotreating separator unit including a hydrotreating high pressure separator 81 and a hydrotreating low pressure separator 82 connected in series, where the output of the hydrotreating unit 5 is connected to the inlet of the hydrotreating high pressure separator 81 through a pipeline; the finished hydrotreated stream is separated at high pressure in a high-pressure hydrotreating separator 81 to obtain a hydrotreated hydrogen-rich gas and a hydrotreated high-pressure separated liquid phase stream, and then the hydrotreated separated at a high pressure liquid-phase stream is separated at low pressure in a low-pressure hydrotreating separator 82 to obtain a hydrotreated gas and hydrotreated liquid phase flow.

Preferably, the apparatus provided in the present invention further includes a hydrotreating distillation column 9, where the inlet of the hydrotreating distillation column 9 is connected to the outlet of the low-pressure hydrotreating separator 82 through a pipeline; the hydrotreated liquid phase stream is fractionated in a hydrotreating distillation column 9 to obtain hydrotreated naphtha and hydrotreated diesel fuel.

Hydrotreating high pressure separator 61 and hydrotreating high pressure separator 81 are not particularly limited in the present invention; in other words, they can be high pressure separators traditionally used in the art. In addition, the low-pressure hydroprocessing separator 62 and the low-pressure hydrotreating separator 82 are not particularly limited, in other words, they can be low-pressure separators conventionally used in the art.

The hydrotreatment distillation column 7 is not particularly limited in the present invention, provided that the above products can be obtained by fractionation. One of skill in the art can fractionate a hydrotreated liquid phase stream specifically in accordance with specific product requirements. Products obtained by fractionation of a hydrotreated liquid phase stream are described above and are not discussed in more detail herein.

The distillation column 9 hydrotreatment is not particularly limited in the present invention, provided that the above products can be obtained by fractionation. One skilled in the art can fractionate a hydrotreated liquid phase stream specifically in accordance with specific product requirements. Products obtained by fractionation of a hydrotreated liquid phase stream are described above and are not discussed in more detail herein.

According to a preferred embodiment of the present invention, the outlet for the gas phase of the hydrotreating high-pressure separator 61 and the outlet for the gas phase of the hydrotreating high-pressure separator 81 are connected to the inlet of the first hydroprocessing unit 1 and / or the inlet of the second hydroprocessing unit 3, respectively and independently, for recycling the hydrotreated rich hydrogen gas and hydrotreated hydrogen-rich gas to provide the hydrogen needed for installation. The specific method for their use is described above, and it is not discussed in more detail in this document.

According to another embodiment of the present invention, the prepared hydrotreated stream and the finished hydrotreated stream are mixed to form a mixed stream, and then the mixed stream is processed by separation and fractionation. This embodiment is more favorable for reducing equipment investment.

Preferably, the installation provided in the present invention further includes:

a mixing separator block and a mixing distillation column 11, where the mixing separator block includes a high pressure mixing separator 101 and a low pressure mixing separator 102 connected in series, and the output of the low pressure mixing separator 102 is connected to the inlet of the mixing distillation column 11; the output of the second hydroprocessing unit 3 and the output of the hydrotreating unit 5 are connected to the inlet of the high-pressure mixing separator 101; the prepared hydrotreated stream and the finished hydrotreated stream are mixed and then separated at high pressure in a high-pressure mixing separator 101 to obtain a mixed hydrogen-rich gas and a mixed high-pressure liquid phase stream.

The mixed high-pressure liquid-phase stream is separated at low pressure in a low-pressure mixing separator 102 to produce a mixed gas and a mixed liquid-phase stream.

The mixed liquid phase stream is fractionated in a mixing distillation column 11 to obtain a mixed naphtha, a mixed diesel fuel and a mixed heavy fraction.

The high-pressure mixing separator 101 is not particularly limited. In other words, the high-pressure mixing separator 101 may be any high-pressure separator conventionally used in the art. Similarly, the low-pressure mixing separator 102 is not particularly limited. In other words, the low pressure mixing separator 102 may be any low pressure separator conventionally used in the art.

The mixing distillation column 7 is not particularly limited in the present invention, provided that the above products can be obtained by fractionation. One of skill in the art can fractionate a mixed liquid phase stream specifically in accordance with specific product requirements. Products obtained by fractionating a mixed liquid phase stream are described above and are not discussed in more detail herein.

According to a preferred embodiment of the present invention, the outlet for the gas phase from the high-pressure mixing separator 101 is connected to the inlet of the first hydroprocessing unit 1 and / or the inlet of the second hydroprocessing unit 3 for recirculating the mixed hydrogen-rich gas to provide the hydrogen needed for the installation. A specific use is described above and is not discussed in more detail herein.

Hereinafter, a method and apparatus for hydrogenating paraffin oil in an embodiment of the present invention is described with reference to FIG. 3.

(1) Paraffin oil and hydrogen-containing gas are fed to a hydroprocessing reactor equipped with a first hydroprocessing unit 1 (first hydroprocessing catalyst layer), a second hydroprocessing unit 3 (second hydroprocessing catalyst layer) and a gas-liquid separator 2 located between the first hydroprocessing unit 1 and the second unit 3 hydrotreatment. A portion of the first hydrotreated stream (first hydrotreated stream A) passing through the catalyst bed of the first hydrotreatment is separated by gas-liquid separation in a gas-liquid separator 2 to obtain a first hydrotreated gas-phase stream and a first hydrotreated liquid-phase stream;

(2) The remainder of the first hydrotreated stream (first hydrotreated stream B), the first hydrotreated liquid phase stream and a hydrogen-containing gas are fed into the catalyst bed of the second hydrotreatment to obtain the finished hydrotreated stream, the finished hydrotreated stream is fed to the high-pressure hydroprocessing separator 61 and separated by high pressure separation to obtain a hydrotreated hydrogen-rich gas and a hydrotreated high-pressure liquid-phase stream, hydrotreatment The high-pressure liquid-phase cleaned bottoms stream is fed to a low-pressure hydroprocessing separator 62 and separated by low-pressure separation to obtain a hydrotreated gas and a hydrotreated liquid-phase stream; a hydrotreated liquid phase stream is fractionated in a hydrotreatment distillation column 7 to obtain hydrotreated naphtha, hydrotreated diesel fuel and hydrotreated heavy fraction;

(3) The light catalytic cracking gas oil recycled through the catalytic cracking light gas oil feeding unit 4 is separated in a distillation column 12 for light catalytic cracking gas oil into a light fraction and a heavy fraction, and a heavy fraction and a first hydrotreated gas phase stream (1) is fed to a hydrotreating unit 5 provided with a first hydrotreating unit 51 (a first hydrotreating catalyst bed) and a second hydrotreating unit 52 (a second hydrotreating catalyst bed cleaning). The heavy fraction and the first hydrotreated gas-phase stream obtained in step (1) are passed through the catalyst bed of the first hydrotreatment to obtain the first hydrotreated stream, and the first hydrotreated stream and the light fraction are passed through the catalyst bed of the second hydrotreatment to obtain the finished hydrotreated stream. The finished hydrotreated stream is fed to a high-pressure hydrotreating separator 81, separated by high-pressure separation to obtain a hydrotreated hydrogen-rich gas and a hydrotreated high-pressure liquid phase stream, and a hydrotreated high-pressure separated liquid phase is fed to a low-pressure hydrotreating separator 82 and separated by separation low pressure to obtain hydrotreated gas and hydrotreated liquid phase flow; the hydrotreated liquid phase stream is fractionated in a hydrotreating distillation column to obtain hydrotreated naphtha and hydrotreated diesel fuel.

The hydrotreated gas obtained in step (2) and the hydrotreated gas obtained in step (3) can be selected as separate products or can be mixed to produce a mixed gaseous product. The hydrotreated naphtha obtained in step (2) and the hydrotreated naphtha obtained in step (3) may be selected as separate products or may be mixed to form a mixed naphtha product. Hydrotreated diesel fuel obtained in stage (2), and hydrotreated diesel fuel obtained in stage (3) can be selected as separate products or can be mixed to obtain a mixed product - diesel fuel. The hydrotreated heavy fraction obtained in stage (2) can be used as raw material for the FCC installation.

Hydrotreated hydrogen-rich gas and hydrotreated hydrogen-rich gas are recycled and used together with fresh hydrogen to provide the hydrogen-containing gas needed for the device.

Further, the present invention is described in more detail in the examples, but the scope of the present invention is not limited to these examples.

In the following examples, hydrotreatment catalysts are FZC-100, FZC-105 and FZC-106 hydrotreatment catalysts developed by Sinopec Dalian (Fushun) Research Institute of Petroleum and Petrochemicals;

The first hydroprocessing catalyst and the second hydroprocessing catalyst are FF-24 catalyst developed by Sinopec Dalian (Fushun) Research Institute of Petroleum and Petrochemicals;

The hydrotreating catalyst is an FHUDS-5 catalyst developed by Sinopec Dalian (Fushun) Research Institute of Petroleum and Petrochemicals.

The main properties of paraffin oil and light recycle gas oil catalytic cracking are presented in table 1.

Examples 1-3

(1) In accordance with the apparatus of FIG. 1, paraffin oil as a raw material and a hydrogen-containing gas are fed to a hydroprocessing reactor, which is equipped with a first hydroprocessing unit 1 (catalyst bed of the first hydroprocessing), a second hydroprocessing unit 3 (catalyst layer of the second hydroprocessing) and a gas-liquid separator 2 located between the first hydroprocessing unit and the second block 3 hydroprocessing. A portion of the first hydrotreated stream (first hydrotreated stream A) passing through the catalyst bed of the first hydrotreatment is separated by gas-liquid separation in a gas-liquid separator 2 to obtain a first hydrotreated gas-phase stream and a first hydrotreated liquid-phase stream. The first hydroprocessing conditions are presented in table 2.

(2) The remainder of the first hydrotreated stream (first hydrotreated stream B), the first hydrotreated liquid phase stream and hydrogen-containing gas are fed into the catalyst bed of the second hydrotreatment to obtain the finished hydrotreated stream, the finished hydrotreated stream is fed to the high-pressure hydroprocessing separator 61 and separated by high pressure separation to obtain a hydrotreated hydrogen-rich gas and a hydrotreated high-pressure liquid phase stream, wherein droobrabotanny separated by high pressure liquid-phase stream is fed to low pressure separator 62 and the hydrotreatment is separated by low pressure separation to obtain hydrotreated and the hydrotreated liquid-phase gas stream; a hydrotreated liquid phase stream is fractionated in a hydrotreatment distillation column 7 to obtain a hydrotreated naphtha (boiling range is 38-150 ° C), hydrotreated diesel fuel (boiling range is 150-365 ° C) and a hydrotreated heavy fraction (boiling range is> 365 ° C). The second hydroprocessing conditions are presented in table 2;

(3) The light catalytic cracking gas oil recycle supplied by the light catalytic cracking gas recycle feed unit 4, and the first hydrotreated gas phase stream obtained in step (1), are fed to the hydrotreating unit 5 provided with a hydrotreating catalyst layer and the light catalytic cracking gas recycle and the first hydrotreated gas phase stream is passed through a hydrotreating catalyst bed to form a finished hydrotreated stream. The finished hydrotreated stream is fed to a high-pressure hydrotreating separator and separated by high-pressure separation to obtain a hydrotreated hydrogen-rich gas and a hydrotreated high-pressure liquid phase stream, and a hydrotreated high-pressure liquid phase is fed to a low-pressure hydrotreating separator 82 and separated by low-pressure separation pressure to obtain hydrotreated gas and hydrotreated liquid phase flow; the hydrotreated liquid phase stream is fractionated in a hydrotreating distillation column 9 to obtain hydrotreated naphtha (boiling range 38–150 ° C) and hydrotreated diesel fuel (boiling range> 150 ° C). Hydrotreating conditions are presented in table 2.

In this case, the hydrotreated hydrogen-rich gas and the hydrotreated hydrogen-rich gas are recycled and used together with fresh hydrogen to provide a hydrogen-containing gas (volumetric hydrogen content of approximately 88-92%) required for installation.

In table 2, the FZC series refers to a composite of 10 vol. % FZC-100, 30 vol. % FZC-105 and 60 o6.% FZC-106.

The properties of the products obtained in examples 1-3 are presented in table 3.

Comparative Example 1

Paraffin oil (paraffin oil 1) is fed as a raw material and a hydrogen-containing gas to a hydroprocessing reactor, which is provided with a layer of a hydroprocessing catalyst, and paraffin oil and hydrogen-containing gas are passed through a layer of a hydroprocessing catalyst to conduct a hydroprocessing reaction (reaction conditions are the same as the reaction conditions of the first hydroprocessing in example 1) to obtain a hydrotreated stream. The hydrotreated stream is separated in a high temperature high pressure separator to obtain a high temperature gas phase and a liquid phase.

The high temperature gas phase obtained by separation in a high temperature high pressure separator is mixed with light catalytic cracking gas oil (such as the light catalytic cracking gas oil in Example 1, the weight ratio of light catalytic cracking gas oil to paraffinic oil is 0.3: 1, and then the mixture is subjected to a hydrotreatment reaction (the conditions are the same as those in Example 1) in a hydrotreatment reactor to obtain a finished hydrotreated stream. The finished hydrotreated stream is separated by high pressure separation and low pressure separation in accordance with step (3) in Example 1 to obtain a hydrotreated hydrogen-rich gas, hydrotreated gas and hydrotreated high-pressure liquid phase stream. The hydrotreated liquid phase separated at high pressure is fractionated in accordance with step (3) in Example 1 to obtain hydrotreated naphtha and hydrotreated diesel fuel.

The liquid phase obtained by separation in a high-temperature high-pressure separator is fed to a hydrotreatment distillation column and fractionated in accordance with step (2) in Example 1 to obtain hydrotreated naphtha, hydrotreated diesel fuel and hydrotreated heavy fraction.

The properties of the obtained products are presented in table 3.

Example 4

The method described in Example 2 is used, but the finished hydrotreated stream and the finished hydrotreated stream are mixed and then separated and fractionated together. More specific:

(1) perform in accordance with stage (1) in example 2;

(2) perform in accordance with stage (2) in example 2 to obtain a finished hydrotreated stream;

(3) perform in accordance with stage (3) in example 2 to obtain the finished hydrotreated stream;

(4) in accordance with the installation of FIG. 2, the finished hydrotreated stream obtained in stage (2) and the finished hydrotreated stream obtained in stage (3) are mixed to obtain a mixed stream, the mixed stream is fed to a high pressure mixing separator 101 for high pressure separation to obtain a mixed hydrogen rich gas and a mixed high-pressure separated liquid phase stream, the mixed high-pressure separated liquid phase stream is fed to a low pressure mixing separator 102 for low pressure separation to obtain a mixed gas and mixed liquid-phase flow; the mixed liquid phase stream is fractionated in a mixing distillation column 11 to obtain a mixed naphtha (the boiling range is 38-150 ° C), a mixed diesel fuel (the boiling range is 150-365 ° C) and a mixed heavy fraction (the boiling range is> 365 °).

In this case, the mixed hydrogen-rich gas is recycled and used together with fresh hydrogen to provide a hydrogen-containing gas (volumetric content of hydrogen is approximately 88-92%) required for installation.

The properties of the obtained products are presented in table 4.

Examples 5-7

(1) In accordance with the apparatus of FIG. 3, the first hydroprocessing and gas-liquid separation is carried out in accordance with examples 1-3. The conditions of the first hydrotreatment are presented in table 5.

(2) Perform in accordance with examples 1-3. The conditions of the second hydrotreatment are presented in table 5.

(3) The light catalytic cracking gas oil recycle supplied by the catalytic cracking light gas cycle oil feeding unit 4 is separated in a light cycle catalytic cracking gas oil distillation column 12 into a light fraction and a heavy fraction. The cut-off temperature is presented in Table 5. The heavy fraction and the first hydrotreated gas-phase stream obtained in stage (1) are fed to the hydrotreating unit 5, equipped with a first hydrotreating unit 51 (first hydrotreating catalyst layer) and a second hydrotreating unit 52 (second hydrotreating catalyst layer) . The heavy fraction and the first hydrotreated gas-phase stream obtained in stage (1) are passed through the catalyst bed of the first hydrotreatment to obtain a first hydrotreated stream, and the first hydrotreated stream and light fraction are passed through the catalyst bed of the second hydrotreatment to obtain a finished hydrotreated stream. The conditions of the first hydrotreatment and the conditions of the second hydrotreatment are presented in table 5. The separation and fractionation of the finished hydrotreated stream is carried out in accordance with examples 1-3.

In this case, the hydrotreated hydrogen-rich gas and the hydrotreated hydrogen-rich gas are recycled and used together with fresh hydrogen to provide a hydrogen-containing gas (volumetric hydrogen content of approximately 88-92%) required for the installation.

In table 5, the FZC series refers to a composite of 10 vol. % FZC-100, 30 vol. % FZC-105 and 60 o6.% FZC-106.

The properties of the products obtained in examples 5-7 are presented in table 6.

From the results of the examples of the present invention, it can be seen that the desired products can be obtained with various properties on demand using the method and installation for the hydrogenation of paraffinic oil provided in the present invention; in addition, the sulfur content of hydrotreated naphtha, hydrotreated naphtha, hydrotreated diesel fuel, hydrotreated diesel fuel and hydrotreated heavy fraction can be effectively reduced, and the content of monocyclic aromatic hydrocarbons in hydrotreated diesel fuel can be increased. Thus, hydrotreated diesel fuel can be used as a high quality FCC feedstock, and the aromatic hydrocarbon content of FCC gasoline can be increased when the specified product is fed to the FCC unit. From the comparison results of Examples 1-3 and Examples 5-7, it can be seen that the preferred embodiment of the present invention is more favorable for reducing the sulfur content in the products, and the content of monocyclic aromatic hydrocarbons in hydrotreated diesel fuel can be further increased.

Although the invention has been described above in detail in certain preferred embodiments with reference to the accompanying drawings, the present invention is not limited to these embodiments. Various simple changes may be made, including combinations of technical features in various other suitable ways, in accordance with the flow chart of the present invention, within the scope of the technical concept of the present invention, but such changes and combinations should be considered disclosed in the present invention and fall within the scope of legal protection of the present invention .

Claims (60)

1. The method of hydrogenation of paraffin oil, comprising the following stages: (1) contacting the paraffinic oil as a feedstock and a hydrogen-containing gas with a first hydroprocessing catalyst under the conditions of the first hydroprocessing, dividing the first hydroprocessed stream resulting from the contact into two parts, i.e. the first hydrotreated stream A and the first hydrotreated stream B, and performing gas-liquid separation of the first hydrotreated stream A to obtain a first hydrotreated gas-phase stream and a first hydrotreated liquid-phase stream; (2) providing contact of the first hydrotreated stream B, the first hydrotreated liquid phase stream and a hydrogen-containing gas with the second hydrotreatment catalyst under conditions of the second hydrotreatment to obtain a finished hydrotreated stream; and (3) contacting the first hydrotreated gas-phase stream and light catalytic cracking gas oil with a hydrotreating catalyst to carry out a hydrotreating reaction under hydrotreating conditions to obtain a ready hydrotreated stream, wherein the initial boiling point of light catalytic cracking gas oil is 100-200 ° C, and the final the boiling point of light recycle gas oil of catalytic cracking is 320-400 ° C, the first hydrotreated stream A is 5-95 wt.% from her weight of the first hydrotreated stream A and stream B first hydrotreated, hydrotreated gas phase stream is 5-95 vol.% hydrogen-containing gas in step (1). 2. A method for hydrogenating paraffin oil, comprising the following steps: (1) contacting the paraffinic oil as a feedstock and a hydrogen-containing gas with a first hydroprocessing catalyst under the conditions of the first hydroprocessing, dividing the first hydroprocessed stream resulting from the contact into two parts, i.e. the first hydrotreated stream A and the first hydrotreated stream B, and performing gas-liquid separation of the first hydrotreated stream A to obtain a first hydrotreated gas-phase stream and a first hydrotreated liquid-phase stream; (2) providing contact of the first hydrotreated stream B, the first hydrotreated liquid phase stream and a hydrogen-containing gas with the second hydrotreatment catalyst under conditions of the second hydrotreatment to obtain a finished hydrotreated stream; (3) separating the light recycle gas oil of catalytic cracking to obtain a light fraction and a heavy fraction, where the cut-off temperature is 245-300 ° C and contacting the first hydrotreated gas-phase stream, heavy fraction and a hydrogen-containing gas with the first hydrotreating catalyst for the first hydrotreating reaction under conditions first hydrotreating to obtain a first hydrotreated stream; then contacting the first hydrotreated stream, light fraction and hydrogen-containing gas with a second hydrotreating catalyst for conducting a second hydrotreating reaction under conditions of a second hydrotreating to obtain a finished hydrotreated stream; the initial boiling point of light recycle gas oil of catalytic cracking is 100-200 ° C, and the final boiling point of light recycle gas oil of catalytic cracking is 320-400 ° C, the first hydrotreated stream A is 5-95 wt.% of the total mass of the first hydrotreated stream A and the first hydrotreated stream B, the hydrotreated gas-phase stream is 5-95 vol.% Hydrogen-containing gas in stage (1). 3. The method according to p. 1 or 2, in which the initial boiling point of paraffin oil is 100-400 ° C, and the final boiling point of paraffin oil is 405-650 ° C; preferably, paraffin oil is selected from at least one material from vacuum gas oil (VGO), heavy catalytic cracking gas oil (THC), deasphalted oil (DAN), coal tar, a direct coal liquefaction distillation product (PPSU), an indirect coal liquefaction distillation product (PKSU) ), synthetic oil and oil from tar shale. 4. The method according to p. 1 or 2, in which the amount of light recycle gas oil of catalytic cracking is such that the mass ratio of light recycle gas oil of catalytic cracking to paraffin oil is 0.1-3: 1, more preferably 0.3-1.1: 1. 5. The method according to claim 1 or 2, in which the first hydroprocessing catalyst and the second hydroprocessing catalyst contain a carrier and an active component, respectively, and independently, where the active component is selected from at least one metal element of group VIB and / or VIII, and the carrier is alumina and / or silicon-containing alumina; preferably, based on the total weight of the catalyst for the first hydroprocessing and in terms of oxide, the content of the metal element of group VIB is 10-35 wt.%, and the content of the metal element of group VIII is 3-15 wt.%; preferably, based on the total weight of the catalyst for the second hydroprocessing and in terms of oxide, the content of the metal element of group VIB is 10-35 wt.%, and the content of the metal element of group VIII is 3-15 wt.%; preferably, the specific surface area of the first hydroprocessing catalyst is 100-650 m ² / g, and the pore volume of the first hydroprocessing catalyst is 0.15-0.6 ml / g; preferably, the specific surface area of the second hydroprocessing catalyst is 100-650 m ² / g, and the pore volume of the second hydroprocessing catalyst is 0.15-0.6 ml / g. . 6. A process according to claim 1 or 2, wherein the hydroprocessing conditions of the first and second hydrotreating conditions respectively and independently include: a reaction pressure of 3-19 MPa, a reaction temperature of 300-450 ° C, a liquid hourly space velocity of 0.2-6 h ^{- 1} and the volume ratio of hydrogen to oil is 100-2000: 1; preferably the conditions of the first hydroprocessing and the conditions of the second hydroprocessing, respectively and independently, include: a reaction pressure of 4-17 MPa; the reaction temperature is 320-420 ° C, the hourly volumetric rate of the liquid is 0.4-4 h ^-1 and the volumetric ratio of hydrogen to oil is 400-1500: 1. 7. The method according to any one of paragraphs. 1-6, in which the hydrotreated gas-phase stream is 10-80 vol.% Hydrogen-containing gas in stage (1). 8. The method according to any one of paragraphs. 1-6, in which the first hydrotreated stream A is 10-80 wt.% Of the total mass of the first hydrotreated stream A and the first hydrotreated stream B. 9. The method according to any one of paragraphs. 1-6, in which the hydrotreating catalyst contains a carrier and an active component, where the active component is selected from at least one of a group VIB and / or VIII metal elements, and the carrier is alumina and / or silicon-containing alumina; preferably, based on the total weight of the hydrotreating catalyst and in terms of oxide, the content of the Group VIB metal element is 10-35 wt.%, and the content of the Group VIII metal element is 3-15 wt.%; preferably, the specific surface area of the hydrotreating catalyst is 100-650 m ² / g, and the pore volume of the hydrotreating catalyst is 0.15-0.6 ml / g; preferably hydrotreating conditions include: a reaction pressure of 3-19 MPa, a reaction temperature of 260-450 ° C, a liquid hourly space velocity of 0.2-6 h ^-1 , a hydrogen to oil volume ratio of 100-2000: 1, more preferably a reaction temperature of 280 -410 ° C. 10. The method according to p. 2, in which the temperature of the second hydrotreatment reaction is lower than the temperature of the first hydrotreatment reaction; preferably, the temperature of the second hydrotreatment reaction is lower than the temperature of the first hydrotreatment reaction by 5-20 ° C. 11. The method according to any one of paragraphs. 1-10, in which step (2) further comprises treating the finished hydrotreated stream by separation and fractionation to obtain hydrotreated hydrogen rich gas, hydrotreated gas, hydrotreated naphtha, hydrotreated diesel fuel and hydrotreated heavy fraction; step (3) further includes treating the final hydrotreated stream by separation and fractionation to obtain hydrotreated hydrogen rich gas, hydrotreated gas, hydrotreated naphtha and hydrotreated diesel fuel; preferably, the separation in step (2) includes high pressure separation and low pressure separation, the finished hydrotreated stream is treated by high pressure separation to obtain a hydrotreated hydrogen rich gas and a hydrotreated high pressure separated liquid phase stream, and then the hydrotreated high pressure separated liquid phase is treated by low pressure separation to produce hydrotreated gas and hydrotreated liquid phase stream, and a hydrotreated liquid phase stream is fractionated to obtain hydrotreated naphtha, hydrotreated diesel fuel and hydrotreated heavy fraction; preferably, the separation in step (3) includes high pressure separation and low pressure separation, the obtained hydrotreated stream is treated by high pressure separation to obtain a hydrotreated hydrogen-rich gas and hydrotreated high-pressure liquid phase stream, and then the hydrotreated high-pressure liquid phase stream is treated by low pressure separation to obtain hydrotreated gas and hydrotreated liquid phase flow, and hydrotreated idkofazny stream is fractionated to obtain a hydrotreated naphtha, and hydrotreated diesel fuel; preferably, the method further includes recycling the hydrotreated hydrogen rich gas and the hydrotreated hydrogen rich gas to provide the desired hydrogen-containing gas. 12. The method according to any one of paragraphs. 1-10, further comprising mixing the finished hydrotreated stream and the finished hydrotreated stream to form a mixed stream and then processing the mixed stream by separation and fractionation; preferably, the mixed stream is treated by high pressure separation to obtain a mixed hydrogen-rich gas and a mixed high-pressure separated liquid-phase stream, and then the mixed high-pressure separated liquid-phase stream is treated by low-pressure separation to obtain a mixed gas and a mixed liquid-phase stream, and a mixed liquid-phase stream subjected to fractionation to obtain a mixed naphtha, a mixed diesel fuel and a mixed heavy fraction ; preferably, the method further comprises recycling the mixed hydrogen rich gas to provide the desired hydrogen containing gas. 13. Installation for the hydrogenation of paraffin oil, including: the first block (1) hydroprocessing; a gas-liquid separator (2), designed to carry out gas-liquid separation of a portion of the first hydrotreated stream obtained in the first hydroprocessing unit to obtain a first hydrotreated gas-phase stream and a first hydrotreated liquid-phase stream; a second hydroprocessing unit (3) intended for performing therein a second hydroprocessing of the remaining part of the first hydroprocessed stream and the first hydroprocessed liquid phase stream to obtain a finished hydroprocessed stream; a catalytic cracking light recycle gas oil supply unit (4) for supplying a catalytic cracking light gas oil recycle unit, and a hydrotreating unit (5) for hydrotreating a catalytic cracking light recycle gas oil thereof, supplied by a catalytic cracking light recycle gas oil unit (4); cracking, and hydrotreated gas-phase stream to obtain a finished hydrotreated stream. 14. Installation for the hydrogenation of paraffin oil, including: the first block (1) hydroprocessing; a gas-liquid separator (2), designed to carry out gas-liquid separation of a portion of the first hydrotreated stream obtained in the first hydroprocessing unit to obtain a first hydrotreated gas-phase stream and a first hydrotreated liquid-phase stream; a second hydroprocessing unit (3) intended for performing therein a second hydroprocessing of the remaining part of the first hydroprocessed stream and the first hydroprocessed liquid phase stream to obtain a finished hydroprocessed stream; a catalytic cracking light recycle gas oil supply unit (4) for supplying a catalytic cracking light recycle gas oil, a hydrotreating unit (5) including a first hydrotreating unit (51) and a second hydrotreating unit (52) arranged in series; a distillation column (12) for light catalytic cracking gas oil, located between the first hydrotreating unit (51) and a light catalytic cracking gas oil supply unit (4) for separating light catalytic cracking gas oil supplied through a light catalytic light gas oil feeding unit (4) cracking, to light fraction and heavy fraction; the heavy fraction and the first hydrotreated gas phase stream are hydrotreated in a first hydrotreatment unit (51) to obtain a first hydrotreated stream; the first hydrotreated stream and the light fraction are hydrotreated in a second hydrotreatment unit (52) to obtain a finished hydrotreated stream. 15. Installation according to claim 13 or 14, in which the gas-liquid separator (2) includes an inlet for a reagent, a pipeline for a liquid phase and a pipeline for a gas phase; the inlet for the reagent of the gas-liquid separator (2) is connected to the outlet of the first hydroprocessing unit (1), the first hydroprocessed liquid-phase stream is sent to the second hydroprocessing unit (3) through the liquid phase pipeline, and the first hydroprocessed gas-phase stream is sent to the hydrotreating unit (5) through the pipeline for the gas phase. 16. Installation according to any one of paragraphs. 13-15, further comprising: a hydroprocessing separator unit including a hydroprocessing high pressure separator (61) and a hydroprocessing low pressure separator (62) connected in series, while the output of the second hydroprocessing unit (3) is connected to the inlet of the hydroprocessing high pressure separator (61) through a pipeline; the finished hydrotreated stream is separated at high pressure in a hydroprocessing high-pressure separator (61) to obtain a hydrotreated hydrogen-rich gas and a hydrotreated high-pressure liquid-phase stream, and then the hydrotreated high-pressure liquid-phase stream is separated at low pressure in a low-pressure separator (62) hydrotreatment to obtain hydrotreated gas and hydrotreated liquid phase stream; hydrotreatment distillation column (7), where the hydrotreatment distillation column inlet (7) is connected to the outlet of the hydroprocessing low-pressure separator (62) through a pipeline, the hydrotreated liquid-phase stream is fractionated in the hydrotreatment distillation column (7) to obtain hydrotreated naphtha, hydrotreated diesel fuel and hydrotreated diesel fuel heavy fraction; a hydrotreating separator unit including a hydrotreating high pressure separator (81) and a hydrotreating low pressure separator (82) connected in series, where the output of the hydrotreating unit (5) is connected to the inlet of the hydrotreating high pressure separator (81) through a pipeline; the finished hydrotreated stream is separated at high pressure in a hydrotreating high-pressure separator (81) to obtain a hydrotreated hydrogen-rich gas and a hydrotreated high-pressure liquid phase stream, and then the hydrotreated high-pressure liquid phase is separated at low pressure in a low pressure separator (82) hydrotreating to obtain hydrotreated gas and hydrotreated liquid phase stream; and a hydrotreating distillation column (9), where the hydrotreating distillation column (9) inlet is connected to the outlet of a hydrotreating low-pressure separator (82) through a pipeline, the hydrotreated liquid-phase stream is fractionated in a hydrotreating distillation column (9) to obtain hydrotreated naphtha and hydrotreated diesel fuel. 17. Installation according to claim 15, in which the outlet for the gas phase of the hydrotreating high-pressure separator (61) and the outlet for the gas phase of the hydrotreating high-pressure separator (81) are connected to the inlet of the first hydroprocessing unit (1) and / or the inlet of the second unit (3 ) hydrotreatment, respectively and independently, to recycle the hydrotreated hydrogen rich gas and the hydrotreated hydrogen rich gas to provide the hydrogen needed for the installation. 18. Installation according to claim 13 or 15, further comprising: a mixing separator block and a mixing distillation column (11), wherein the mixing separator block includes a high pressure mixing separator (101) and a low pressure mixing separator (102) connected in series, and the output of the low pressure mixing separator (102) is connected to the input of the mixing distillation columns (11); the output of the second hydrotreating unit (3) and the hydrotreating unit (5) are connected to the inlet of the high-pressure mixing separator (101); the prepared hydrotreated stream and the finished hydrotreated stream are mixed and then separated at high pressure in a high-pressure mixing separator (101) to obtain a mixed hydrogen-rich gas and a mixed high-pressure liquid-phase stream; the mixed high-pressure liquid-phase stream is separated at low pressure in a low-pressure mixing separator (102) to produce a mixed gas and a mixed liquid-phase stream; the mixed liquid phase stream is subjected to fractionation in a mixing distillation column (11) to obtain a mixed naphtha, mixed diesel fuel and mixed heavy fraction; preferably the gas phase outlet of the high-pressure mixing separator (101) is connected to the inlet of the first hydroprocessing unit (1) and / or the inlet of the second hydroprocessing unit (3) to recycle the mixed hydrogen-rich gas to provide the hydrogen needed for the installation.

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