Boiling bed-fixed bed system and shutdown method and application

Abstract

The present application relates to a petroleum chemical production process, and discloses a boiling bed-fixed bed system, a shutdown method and application. The boiling bed-fixed bed system comprises a reaction unit, a fractionation unit, a catalyst adding and discharging unit, a circulating hydrogen unit, a fresh hydrogen unit and an inert gas unit. In the direction of raw material flow, the reaction unit comprises a raw material subunit, a heat exchange subunit, a boiling bed reactor subunit, a fixed bed reactor subunit and a separation subunit which are sequentially and serially arranged. The fractionation unit is provided with a discharge pipeline and a circulating pipeline which is communicated with the inlet of the raw material subunit. The outlet of the boiling bed reactor subunit is communicated with the inlet of the catalyst adding and discharging unit. The outlet of the separation subunit is communicated with the inlet of the circulating hydrogen unit. The outlets of the circulating hydrogen unit, the fresh hydrogen unit and the inert gas unit are communicated with the inlets of the fixed bed reactor subunit and the heat exchange subunit.

Description

TECHNICAL FIELD

[0001] The present application relates to a petroleum chemical production process, in particular to a boiling bed-fixed bed system and a shutdown method and application. BACKGROUND

[0002] Both boiling bed process and fixed bed process have practical industrial application devices, at present, boiling bed process and fixed bed process can be combined and applied by setting a fractionation system between boiling bed and fixed bed, such as coal tar boiling bed-fixed bed combined process, but the process of directly combining boiling bed process and fixed bed process has not been applied in industry. The existing technology has few introductions on the shutdown method of boiling bed-fixed bed process, and more stays in the stage of "talking on paper".

[0003] CN108102689 introduces a shutdown method of coal tar hydrogenation process, mainly considering the mutual solubility of the first cleaning oil (hydrogenation treated oil obtained from the coal tar boiling bed hydrogenation treatment reaction unit) and the second cleaning oil (distillate oil obtained from the fixed bed hydrogenation reactor) and the stability of the system, introducing that the first cleaning oil is used for cleaning first, then the second cleaning oil is used for cleaning, after the cleaning is completed, the oil pump is stopped, and the nitrogen gas is used for purging the device to complete the shutdown.

[0004] However, the shutdown methods of boiling bed process and fixed bed process are different, how to connect the shutdown process of the combination of the two processes to realize safe shutdown has not been reported so far. SUMMARY

[0005] The purpose of the present application is to combine the boiling bed shutdown process and the fixed bed shutdown process, considering the shutdown characteristics of the boiling bed process and the fixed bed process respectively, combining the actual shutdown experience, a boiling bed-fixed bed system and a shutdown method and application are provided, the system comprises a reaction unit, a fractionation unit, a catalyst adding and discharging unit, a circulating hydrogen unit, a new hydrogen unit and an inert gas unit, along the flow direction of the raw material, the reaction unit comprises a raw material subunit, a heat exchange subunit, a boiling bed reactor subunit, a fixed bed reactor subunit and a separation subunit which are sequentially and serially arranged, the effective combination of the boiling bed shutdown process and the fixed bed shutdown process can be realized, the shutdown time can be effectively shortened by 3-15 days on the basis of ensuring safe shutdown.

[0006] In order to achieve the above purpose, the first aspect of the present application provides a boiling bed-fixed bed system, which comprises: a reaction unit and a fractionation unit which are sequentially and serially arranged along the flow direction of the raw material;

[0007] Along the flow direction of the raw material, the reaction unit comprises a raw material subunit, a heat exchange subunit, a boiling bed reactor subunit, a fixed bed reactor subunit and a separation subunit which are sequentially and serially arranged;

[0008] The raw material subunit is used to supply raw material oil to the reaction unit. The raw material subunit inlet is equipped with an oil injection pipeline and an injection pipeline. The oil injection pipeline is used to inject shutdown oil into the reaction unit, and the injection pipeline is used to inject functional injection agents into the reaction unit.

[0009] The heat exchange subunit is used to control the temperature of the reaction unit;

[0010] The fluidized bed reactor subunit is used to receive material from the heat exchange subunit;

[0011] The fixed-bed reactor subunit includes at least one fixed-bed reactor, preferably 3-5, and more preferably the fixed-bed reactors are connected in series to receive materials from the fluidized bed reactor subunit.

[0012] The separation subunit is used to separate materials from the fixed-bed reactor subunit;

[0013] The fractionation unit outlet is provided with a circulation pipeline and a discharge pipeline, each used for closed-loop circulation of the system and discharge of materials, respectively. The circulation pipeline is connected to the inlet of the raw material sub-unit.

[0014] The fluidized bed-fixed bed system also includes:

[0015] A catalyst addition and discharge unit is used to receive catalyst and shutdown oil from a fluidized bed reactor subunit, the outlet of which is connected to the inlet of the catalyst addition and discharge unit.

[0016] A circulating hydrogen unit is used to supply circulating hydrogen to the reaction unit. The outlet of the separation subunit is connected to the inlet of the circulating hydrogen unit, and the outlet of the circulating hydrogen unit is connected to the inlet of the fixed-bed reactor subunit and the inlet of the heat exchange subunit, respectively.

[0017] The new hydrogen unit is used to provide the fresh hydrogen required for the reaction unit to consume and to control the pressure of the reaction unit. The outlet of the new hydrogen unit is connected to the inlet of the fixed bed reactor subunit and the inlet of the heat exchange subunit, respectively.

[0018] An inert gas unit is used to provide inert gas to replace the gas phase in the reaction unit. The outlet of the inert gas unit is connected to the inlet of the fixed bed reactor subunit and the inlet of the heat exchange subunit, respectively.

[0019] A second aspect of the present invention provides a shutdown method for the fluidized bed-fixed bed system described in the first aspect of the present invention, the shutdown method comprising:

[0020] (1) The reaction unit is cooled, its flow rate is reduced, and its pressure is decreased;

[0021] (2) through the oil injection pipeline, the raw oil of the reaction unit is replaced by the shutdown oil, the replaced raw oil is discharged to the outside of the system through the discharge pipeline of the fractionation unit outlet, and after the replacement is qualified, the shutdown oil is circulated to the inlet of the raw material subunit through the circulating pipeline of the fractionation unit outlet for closed-loop circulation, and the reaction unit is cooled and depressurized;

[0022] (3) through the injection pipeline, the functional injection agent is injected into the raw material subunit, and is circulated to the inlet of the raw material subunit through the circulating pipeline of the fractionation unit outlet for closed-loop circulation, and the reaction unit is cooled and depressurized, and the ebullated bed reactor subunit is unloaded to the catalyst charging and discharging unit;

[0023] (4) the raw material subunit stops feeding, the ebullated bed reactor subunit is unloaded to the catalyst charging and discharging unit, the reaction unit is pressurized, the shutdown oil of the fixed bed reactor subunit is separated into gas phase and liquid phase through the separation subunit, the gas phase is circulated to the inlet of the fixed bed reactor subunit and the inlet of the heat exchange subunit through the circulating hydrogen unit, and the liquid phase is discharged to the outside of the system through the discharge pipeline of the fractionation unit outlet;

[0024] (5) the reaction unit is circulated, cooled and depressurized, the circulating hydrogen unit is stopped, the reaction unit is depressurized, the inert gas from the inert gas unit is introduced to replace the gas phase in the reaction unit, the replaced gas phase is discharged to the outside of the system through the discharge pipeline of the separation subunit outlet, and after the replacement is qualified, the shutdown is completed.

[0025] The third aspect of the present application provides an application of the shutdown method of the ebullated bed-fixed bed system of the first aspect of the present application or the ebullated bed-fixed bed system of the second aspect of the present application in raw oil hydrogenation, preferably the raw oil is one or more of residual oil, heavy oil, pitch, coal tar and catalytic slurry oil.

[0026] Compared with the prior art, the present application has the following beneficial effects:

[0027] (1) The ebullated bed-fixed bed system provided by the present application is suitable for the combination of ebullated bed process and fixed bed process, and when the system is used for shutdown, the system can be safely shut down and the shutdown time can be effectively shortened by 3-15 days;

[0028] (2) The present application first combines the ebullated bed shutdown process and the fixed bed shutdown process, which fills the gap of the existing shutdown method;

[0029] (3) The shutdown method of the ebullated bed-fixed bed system provided by the present application has the characteristics of safety, reliability, environmental protection and strong operability, the method fully considers the shutdown characteristics of the ebullated bed process and the fixed bed process, and fully identifies the connection and potential risks of each step of the ebullated bed-fixed bed process, effectively avoids the influence of the shutdown oil in the ebullated bed reactor on the fixed bed circulating oil, and realizes the effective connection of the shutdown process when the two processes are combined. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the shutdown process for a fluidized bed-fixed bed system. Detailed Implementation

[0031] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0032] In this invention, unless otherwise stated, directional terms such as "upper," "lower," "top," "bottom," "left," and "right" are generally used to describe the relative positions of components in relation to the directions shown in the accompanying drawings or in relation to the vertical, perpendicular, or gravitational directions.

[0033] According to a first aspect of the present invention, a fluidized bed-fixed bed system is provided, the system comprising: a reaction unit and a fractionation unit arranged in series along the feed flow direction;

[0034] Along the direction of raw material flow, the reaction unit includes a raw material sub-unit, a heat exchange sub-unit, a fluidized bed reactor sub-unit, a fixed bed reactor sub-unit, and a separation sub-unit arranged in series.

[0035] The raw material subunit is used to supply raw material oil to the reaction unit. The raw material subunit inlet is equipped with an oil injection pipeline and an injection pipeline. The oil injection pipeline is used to inject shutdown oil into the reaction unit, and the injection pipeline is used to inject functional injection agents into the reaction unit.

[0036] The heat exchange subunit is used to control the temperature of the reaction unit;

[0037] The fluidized bed reactor subunit is used to receive material from the heat exchange subunit;

[0038] The fixed-bed reactor subunit includes at least one fixed-bed reactor, preferably 3-5, and more preferably the fixed-bed reactors are connected in series to receive materials from the fluidized bed reactor subunit.

[0039] The separation subunit is used to separate materials from the fixed-bed reactor subunit;

[0040] The fractionation unit outlet is provided with a circulation pipeline and a discharge pipeline, each used for closed-loop circulation of the system and discharge of materials, respectively. The circulation pipeline is connected to the inlet of the raw material sub-unit.

[0041] The ebullated bed-fixed bed system further comprises:

[0042] a catalyst charging and discharging unit for receiving catalyst and shutdown oil from the ebullated bed reactor subunit, the outlet of the ebullated bed reactor subunit being in communication with the inlet of the catalyst charging and discharging unit;

[0043] a circulating hydrogen unit for providing circulating hydrogen to the reaction unit, the outlet of the separation subunit being in communication with the inlet of the circulating hydrogen unit, the outlet of the circulating hydrogen unit being in communication with the inlet of the fixed bed reactor subunit and the inlet of the heat exchange subunit, respectively;

[0044] a fresh hydrogen unit for providing fresh hydrogen required by the reaction unit and controlling the pressure of the reaction unit, the outlet of the fresh hydrogen unit being in communication with the inlet of the fixed bed reactor subunit and the inlet of the heat exchange subunit, respectively;

[0045] an inert gas unit for providing inert gas to replace the gas phase in the reaction unit, the outlet of the inert gas unit being in communication with the inlet of the fixed bed reactor subunit and the inlet of the heat exchange subunit, respectively.

[0046] In the present application, the ebullated bed-fixed bed system comprises a reaction unit, a fractionation unit, a catalyst charging and discharging unit, a circulating hydrogen unit, a fresh hydrogen unit and an inert gas unit, along the flow direction of the raw material, the reaction unit comprises a raw material subunit, a heat exchange subunit, an ebullated bed reactor subunit, a fixed bed reactor subunit and a separation subunit arranged in series, suitable for a shutdown process combining ebullated bed shutdown process and fixed bed shutdown process, which can ensure safe shutdown of the system and effectively shorten the shutdown time by 3-15 days when the system is used for shutdown.

[0047] According to the second aspect of the present application, the present application provides a shutdown method of an ebullated bed-fixed bed system, the shutdown method comprising:

[0048] (1) reducing the temperature, quantity and pressure of the reaction unit;

[0049] (2) replacing the raw material oil in the reaction unit with the shutdown oil through the oil injection pipeline, the replaced raw material oil being discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, and after the replacement is qualified, the shutdown oil is circulated to the inlet of the raw material subunit through the circulation pipeline at the outlet of the fractionation unit for closed-loop circulation, and the temperature and pressure of the reaction unit are reduced;

[0050] (3) injecting functional injection agent into the raw material subunit through the injection pipeline, circulating to the inlet of the raw material subunit through the circulation pipeline at the outlet of the fractionation unit for closed-loop circulation, reducing the temperature and pressure of the reaction unit, and unloading the catalyst from the ebullated bed reactor subunit to the catalyst charging and discharging unit;

[0051] (4) The raw material subunit stops feeding, the ebullated bed reactor subunit retreats to stop the oil to the catalyst adding and discharging unit, the reaction unit increases the pressure, the fixed bed reactor subunit's stop oil is separated into gas phase and liquid phase through the separation subunit, the gas phase is recycled to the fixed bed reactor subunit inlet and the heat exchange subunit inlet through the circulating gas unit, and the liquid phase is discharged to the outside of the system through the discharge pipeline of the fractionation unit outlet;

[0052] (5) The reaction unit is cooled and decompressed, the circulating gas unit is stopped, the reaction unit is decompressed, inert gas from the inert gas unit is introduced to replace the gas phase in the reaction unit, the replaced gas phase is discharged to the outside of the system through the discharge pipeline of the separation subunit outlet, and the replacement is completed after being qualified, and the shutdown is completed.

[0053] The ebullated bed shutdown process and the fixed bed shutdown process are combined for the first time, and the blank of the existing shutdown method is made up; in the present application, the shutdown method of the ebullated bed-fixed bed system has the characteristics of safety, reliability, environmental protection and strong operability, the shutdown characteristics of the ebullated bed process and the fixed bed process are fully considered, and the connection and potential risks of each step of the ebullated bed-fixed bed process shutdown are fully identified, the influence of the shutdown oil in the ebullated bed reactor on the fixed bed circulating oil is effectively avoided, and the effective connection of the shutdown process when the two processes are combined is realized.

[0054] According to a preferred embodiment of the present application, in step (1), the reaction unit is cooled through the heat exchange subunit, the amount is reduced through the raw material subunit, and the pressure is reduced through the new gas unit and the separation subunit. The use of the foregoing embodiment helps to introduce the shutdown oil to replace the raw oil in the reaction unit, and facilitates the combination of the ebullated bed-fixed bed shutdown process.

[0055] According to a preferred embodiment of the present application, in step (1), the conditions for cooling the reaction unit include: simultaneously lowering the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit to 340-380℃ at a speed of 5-20℃ / h; preferably, simultaneously lowering the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit to 350-370℃ at a speed of 8-15℃ / h. The use of the foregoing embodiment provides a suitable temperature for introducing the shutdown oil to replace the raw oil in the reaction unit, and especially when the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit is simultaneously lowered to 350-370℃ at a speed of 8-15℃ / h, it is more helpful to effectively connect the shutdown process when the ebullated bed-fixed bed process is combined, and to realize safe, reliable and environmentally friendly shutdown.

[0056] According to a preferred embodiment of the present application, in step (1), the conditions for the reaction unit to reduce the amount of the raw material oil include: reducing the amount of the raw material oil to 60-100% of the design load at a rate of 5-15 t / h; preferably, reducing the amount of the raw material oil to 60-80% of the design load at a rate of 8-15 t / h. The foregoing embodiment provides a suitable amount of the raw material oil for the reaction unit to be replaced by the start-up oil, especially when the reaction unit reduces the amount of the raw material oil to 60-80% of the design load at a rate of 8-15 t / h, which is more conducive to the effective connection of the shutdown process when the ebullated bed-fixed bed process is combined, and realizes safe, reliable and environmentally friendly shutdown.

[0057] According to a preferred embodiment of the present application, in step (1), the conditions for the reaction unit to reduce the pressure include: reducing the pressure of the reaction unit to 8-16 MPa at a rate of 0.1-2.0 MPa / h; preferably, reducing the pressure of the reaction unit to 10-14 MPa at a rate of 0.5-1.5 MPa / h. The foregoing embodiment provides a suitable pressure for the reaction unit to be replaced by the start-up oil, especially when the reaction unit reduces the pressure of the reaction unit to 10-14 MPa at a rate of 0.5-1.5 MPa / h, which is more conducive to the effective connection of the shutdown process when the ebullated bed-fixed bed process is combined, and realizes safe, reliable and environmentally friendly shutdown.

[0058] In the present application, the start-up oil is wax oil, which is optionally diesel oil.

[0059] According to a preferred embodiment of the present application, in step (2), the specific way for the start-up oil to replace the raw material oil of the reaction unit includes:

[0060] Wax oil replaces the raw material oil: wax oil is introduced to replace the raw material oil of the reaction unit through the oil injection pipeline, and the replaced raw material oil is discharged to the outside of the system through the discharge pipeline of the outlet of the fractionation unit. After the replacement is qualified, the wax oil is recycled to the inlet of the raw material subunit through the recycling pipeline of the outlet of the fractionation unit for closed-loop circulation, and the reaction unit is cooled and depressurized. The foregoing embodiment can realize the replacement of the raw material oil of the reaction unit by the start-up oil, and achieve the replacement qualified standard, which is conducive to the combination of the ebullated bed-fixed bed shutdown process.

[0061] According to a preferred embodiment of the present application, in step (2), the specific way for the start-up oil to replace the raw material oil of the reaction unit further includes:

[0062] Diesel oil replaces wax oil: diesel oil is introduced through the oil injection pipeline to open circuit replace the wax oil in the reaction unit, the reaction unit is cooled while open circuit replacement, the replaced wax oil is discharged through the discharge pipeline at the outlet of the fractionation unit to the outside of the system, after the replacement is qualified, the diesel oil is recycled to the inlet of the raw material sub-unit through the recycling pipeline at the outlet of the fractionation unit to realize closed circuit, and the reaction unit is cooled. By using the foregoing embodiment, the raw material oil in the reaction unit can be better replaced by open circuit of the shutdown oil, and the replacement qualified standard can be reached, so that the boiling bed-fixed bed shutdown process can be combined with each other.

[0063] According to a preferred embodiment of the present application, in step (2), the distillation range of the wax oil is 250-530°C, and the wax oil is preferably selected from hydrocracked wax oil or straight-run wax oil, and more preferably is straight-run wax oil. By using the foregoing embodiment, the raw material oil in the reaction unit can be replaced by open circuit of the wax oil, and the cost can be effectively reduced when the wax oil is straight-run wax oil, so that the boiling bed-fixed bed shutdown process can be combined with each other.

[0064] According to a preferred embodiment of the present application, in step (2), the raw material oil is at least one selected from residual oil, heavy oil, pitch, coal tar and catalytic slurry oil, and is preferably residual oil.

[0065] According to a preferred embodiment of the present application, in step (2), the raw material oil in the reaction unit is replaced by open circuit of the wax oil, and the specific mode is that the wax oil feeding amount is increased, and the raw material oil feeding amount is reduced in the same proportion, the replaced raw material oil is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, and the raw material oil in the reaction unit is completely replaced by the wax oil. By using the foregoing embodiment, the replacement efficiency of the raw material oil in the reaction unit replaced by open circuit of the wax oil can be effectively improved, the replacement qualified standard can be reached, and the boiling bed-fixed bed shutdown process can be combined with each other.

[0066] In step (2), when the raw material oil in the reaction unit is replaced by open circuit of the wax oil, the present application does not have special limitation on the wax oil feeding amount, and the skilled in the art can make reasonable selection according to the needs. According to a preferred embodiment of the present application, the wax oil feeding amount is 60-100% by weight of the design load, and is preferably 60-80% by weight. By using the foregoing embodiment, the replacement efficiency of the raw material oil in the reaction unit replaced by open circuit of the wax oil can be effectively improved, and the wax oil amount can be reduced when the wax oil feeding amount is 60-80% by weight of the design load, so that the boiling bed-fixed bed shutdown process can be combined with each other.

[0067] The feed rate of the wax oil is not specially limited in the present application, and can be reasonably selected by those skilled in the art according to the needs. According to a preferred embodiment of the present application, the feed rate of the wax oil is 50-280 t / h, preferably 75-280 t / h. By using the foregoing embodiment, the displacement efficiency of the feed oil of the wax oil open-displacement reaction unit can be effectively improved, and especially when the feed rate of the wax oil is 75-280 t / h, the wax oil consumption can be reduced while the standard of displacement qualification is quickly reached, thereby facilitating the combination of the ebullated bed-fixed bed shutdown process.

[0068] According to a preferred embodiment of the present application, in step (2), the standard of displacement qualification of the feed oil of the wax oil open-displacement reaction unit is that the amount of 538℃ distillate of the hot low-temperature oil is ≥ 85%.

[0069] According to a preferred embodiment of the present application, in step (2), the closed-loop circulation time of the wax oil is 2-12 h, preferably 4-8 h. By using the foregoing embodiment, the residual feed oil in each subunit can be flushed away by the closed-loop circulation of the wax oil in the reaction unit, which is helpful for the complete displacement of the feed oil.

[0070] According to a preferred embodiment of the present application, during the displacement of the feed oil by the wax oil in step (2), the reaction unit is cooled by using a programmed cooling method, and the conditions include: reducing the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit to 260-320℃ at a rate of 5-20℃ / h; preferably, reducing the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit to 280-300℃ at a rate of 5-15℃ / h. By using the foregoing embodiment, a suitable temperature is provided for the wax oil for displacing the reaction unit of the diesel oil, and especially when the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit is reduced to 280-300℃ at a rate of 5-15℃ / h, the shutdown time can be shortened while the safety operation and the displacement conditions of the wax oil are met, so that the ebullated bed-fixed bed process combination can be more effectively connected during the shutdown process, thereby realizing the safe, reliable and environmentally friendly shutdown of the ebullated bed-fixed bed system.

[0071] According to a preferred embodiment of the present application, in the process of replacing the wax oil in the reaction unit with the diesel oil in step (2), the pressure reduction conditions of the reaction unit include: reducing the pressure of the reaction unit to 8-14 MPa at a rate of 0.1-2.0 MPa / h; preferably, reducing the pressure of the reaction unit to 8-12 MPa at a rate of 0.5-1.5 MPa / h. By using the foregoing embodiment, the pressure of the wax oil in the reaction unit is replaced by the diesel oil, especially when the pressure of the reaction unit is reduced to 8-12 MPa at a rate of 0.5-1.5 MPa / h, the safety operation and diesel oil replacement conditions are met, the shutdown time is shortened, the combination of the ebullated bed and fixed bed processes during shutdown is more effectively connected, and the ebullated bed-fixed bed system is safe, reliable and environmentally friendly during shutdown.

[0072] According to a preferred embodiment of the present application, in step (2), the distillation range of the diesel oil is 195-390°C, and the diesel oil is preferably any one selected from the group consisting of hydrodesiel, straight-run diesel oil and catalytic diesel oil, and more preferably the straight-run diesel oil. By using the foregoing embodiment, the wax oil in the reaction unit is replaced by the diesel oil, especially when the diesel oil is the straight-run diesel oil, the wax oil in the reaction unit is better replaced, and the combination of the ebullated bed and fixed bed processes during shutdown is facilitated.

[0073] According to a preferred embodiment of the present application, in step (2), the wax oil in the reaction unit is replaced by the diesel oil, and the specific method is: increasing the feed amount of the diesel oil while proportionally reducing the feed amount of the wax oil, discharging the replaced wax oil from the outlet pipeline of the fractionation unit to the outside of the system, and replacing the wax oil in the reaction unit with the diesel oil. By using the foregoing embodiment, the replacement efficiency of the wax oil in the reaction unit by the diesel oil is effectively improved, the replacement standard is met, and the combination of the ebullated bed and fixed bed processes during shutdown is facilitated.

[0074] In step (2), the wax oil in the reaction unit is replaced by the diesel oil, and the feed amount of the diesel oil is not particularly limited in the present application, as long as the replacement standard is met, and can be reasonably selected by those skilled in the art according to the needs. According to a preferred embodiment of the present application, the feed amount of the diesel oil is 60-100% by weight of the design load, and preferably 60-80% by weight. By using the foregoing embodiment, the replacement efficiency of the wax oil in the reaction unit by the diesel oil is effectively improved, especially when the feed amount of the diesel oil is 60-80% by weight of the design load, the replacement standard is met quickly, the diesel oil consumption is reduced, and the combination of the ebullated bed and fixed bed processes during shutdown is facilitated.

[0075] The present application does not have special restrictions on the feeding speed of the diesel oil, and the skilled in the art can make reasonable selection according to the needs. According to a preferred embodiment of the present application, the feeding speed of the diesel oil is 50-280 t / h, preferably 75-280 t / h. By using the foregoing embodiment, the displacement efficiency of the wax oil in the diesel oil open displacement reaction unit can be effectively improved, especially when the feeding speed of the diesel oil is 75-280 t / h, the diesel oil consumption can be reduced while quickly reaching the displacement qualified standard, thereby facilitating the combination of the boiling bed-fixed bed shutdown process.

[0076] According to a preferred embodiment of the present application, in step (2), when the wax oil in the diesel oil open displacement reaction unit is displaced, the reaction unit is cooled to 170-260°C, preferably 170-240°C, while being displaced. By using the foregoing embodiment, the shutdown time can be effectively shortened, especially when the reaction unit is cooled to 170-240°C while being displaced, the shutdown time is shortened while meeting the safe operation and diesel oil displacement conditions, the displacement qualified standard is reached more quickly, thereby facilitating the combination of the boiling bed-fixed bed shutdown process.

[0077] The present application does not have special restrictions on the cooling speed of the reaction unit while being displaced, and the skilled in the art can make reasonable selection according to the needs. According to a preferred embodiment of the present application, the reaction unit is cooled at a speed of 5-20°C / h, preferably 5-10°C / h, while being displaced. By using the foregoing embodiment, the shutdown time can be effectively shortened, especially when the reaction unit is cooled at a speed of 5-10°C / h while being displaced, the shutdown time is shortened while meeting the safe operation and diesel oil displacement conditions, the displacement qualified standard is reached more quickly, thereby facilitating the combination of the boiling bed-fixed bed shutdown process.

[0078] According to a preferred embodiment of the present application, in step (2), when the wax oil in the diesel oil open displacement reaction unit is displaced, the displacement qualified standard is that the 50°C viscosity of the hot low-temperature separated oil and the hydrogenated atmospheric feed oil is ≥10 mm 2 / s.

[0079] According to a preferred embodiment of the present application, in step (2), the closed loop circulation time of the diesel oil is 2-12 h, preferably 4-8 h. By using the foregoing embodiment, the diesel oil is closed loop circulated in the reaction unit, which can flush away the residual wax oil in each subunit, thereby facilitating the complete displacement of the wax oil.

[0080] According to a preferred embodiment of the present application, in the process of replacing the wax oil with diesel in step (2), the temperature reduction conditions of the reaction unit include: reducing the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit to 170-260°C at a rate of 5-20°C / h; preferably, reducing the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit to 170-240°C at a rate of 5-10°C / h. By using the foregoing embodiment, a suitable temperature is provided for injecting the functional injection agent into the raw material subunit, especially when the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit is reduced to 170-240°C at a rate of 5-10°C / h, the shutdown time can be shortened while meeting the injection conditions of the functional injection agent, so that the ebullated bed-fixed bed process combination can be more effectively connected during the shutdown process, thereby realizing safe, reliable and environmentally friendly shutdown of the ebullated bed-fixed bed system.

[0081] According to a preferred embodiment of the present application, in step (3), the functional injection agent includes a flame retardant. By using the foregoing embodiment, a protective film can be formed on the surface of the catalyst by adding the flame retardant, thereby reducing the risk of spontaneous combustion of the catalyst during the injection of the injection agent.

[0082] According to a preferred embodiment of the present application, in step (3), the feeding amount of the functional injection agent is 0.3-2.0% of the oil storage volume of the reaction unit, preferably 0.5-1.0%. By using the foregoing embodiment, the amount of the functional injection agent can be reduced under the premise of safe injection of the injection agent, which is more conducive to environmental protection.

[0083] According to a preferred embodiment of the present application, in step (3), the closed-loop circulation time of the functional injection agent is 8-24h, preferably 10-12h. By using the foregoing embodiment, the functional injection agent can form a protective film on the surface of the catalyst, while reducing the consumption of the functional injection agent.

[0084] According to a preferred embodiment of the present application, in step (3), the temperature reduction conditions of the reaction unit include: reducing the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit to 120-160°C at a rate of 5-25°C / h; preferably, reducing the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit to 140-150°C at a rate of 10-20°C / h. By using the foregoing embodiment, a suitable temperature is provided for unloading the catalyst from the ebullated bed reactor subunit to the catalyst charging and discharging unit, especially when the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit is reduced to 140-150°C at a rate of 10-20°C / h, the shutdown time can be shortened while meeting the function of the functional injection agent.

[0085] According to a preferred embodiment of the present application, in step (3), the pressure reduction conditions of the reaction unit include: reducing the pressure of the reaction unit to 1-5 MPa at a rate of 0.1-2.0 MPa / h; preferably, reducing the pressure of the reaction unit to 1-2 MPa at a rate of 0.5-1.5 MPa / h. With the foregoing embodiment, suitable pressure is provided for the catalyst unloading of the ebullated bed reactor subunit to the catalyst charging and discharging unit, and especially when the pressure of the reaction unit is reduced to 1-2 MPa at a rate of 0.5-1.5 MPa / h, the efficiency of the catalyst unloading of the ebullated bed reactor subunit can be effectively improved while meeting the safety operation, and the shutdown time is shortened.

[0086] According to a preferred embodiment of the present application, in step (3), the catalyst unloading rate of the ebullated bed reactor subunit is 14-48 m 3 / h, preferably 19-24 m 3 / h. With the foregoing embodiment, especially when the catalyst unloading rate of the ebullated bed reactor subunit is 19-24 m 3 / h, the oil delivery amount is reduced while meeting the catalyst unloading rate of the ebullated bed reactor subunit.

[0087] In step (4), after the raw material subunit stops feeding, the ebullated bed reactor subunit retreats the shutdown oil to the catalyst charging and discharging unit. The present application does not have special limitations on the retreat rate of the ebullated bed reactor subunit, and a person skilled in the art can reasonably select as needed. According to a preferred embodiment of the present application, the retreat rate of the ebullated bed reactor subunit to the catalyst charging and discharging unit is 10-50 m 3 / h, preferably 20-40 m 3 / h. With the foregoing embodiment, especially when the retreat rate of the ebullated bed reactor subunit to the catalyst charging and discharging unit is 20-40 m 3 / h, the efficiency of the ebullated bed reactor subunit retreat of the shutdown oil can be effectively improved while meeting the pipeline flow capacity.

[0088] According to a preferred embodiment of the present application, in step (4), the conditions for the reaction unit to increase pressure include: increasing the pressure of the reaction unit to 1-10 MPa at a rate of 0.1-2.0 MPa / h; preferably, increasing the pressure of the reaction unit to 4-8 MPa at a rate of 0.5-1.5 MPa / h. By using the foregoing embodiment, the appropriate pressure is provided for the circulating oil of the fixed bed reactor subunit, and especially when the reaction unit increases the pressure of the reaction unit to 4-8 MPa at a rate of 0.5-1.5 MPa / h, the influence of the shutdown oil of the ebullated bed reactor subunit on the circulating oil of the fixed bed reactor subunit can be effectively avoided, which helps to effectively connect the shutdown process when the ebullated bed-fixed bed process is combined, thereby realizing safe, reliable and environmentally friendly shutdown.

[0089] In step (4), the shutdown oil of the fixed bed reactor subunit is separated into a gas phase and a liquid phase by the separation subunit, the gas phase is circulated to the inlet of the fixed bed reactor subunit and the inlet of the heat exchange subunit by the circulating hydrogen subunit, and the liquid phase is discharged to the outside of the system through the discharge pipeline of the fractionation subunit outlet. In the present application, the gas phase and the liquid phase are obtained by separating the oil gas brought out by circulation in the fixed bed unit, and the specific components of the gas phase and the liquid phase are not described herein.

[0090] According to a preferred embodiment of the present application, in step (5), the conditions for the reaction unit to decrease temperature include: decreasing the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit to 30-60℃ at a rate of 1-5℃ / h; preferably, decreasing the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit to 40-50℃ at a rate of 1-3℃ / h. By using the foregoing embodiment, the required temperature is provided for the shutdown of the circulating hydrogen subunit, and especially when the reaction unit decreases the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit to 40-50℃ at a rate of 1-3℃ / h, the shutdown of the circulating hydrogen subunit can be accelerated, which helps to safely shutdown the ebullated bed-fixed bed system.

[0091] According to a preferred embodiment of the present application, in step (5), the conditions for the reaction unit to decrease pressure include: decreasing the pressure of the reaction unit to 0.1-2.0 MPa at a rate of 0.5-2.0 MPa / h; preferably, decreasing the pressure of the reaction unit to 0.5-1.0 MPa at a rate of 0.5-1.5 MPa / h. By using the foregoing embodiment, the required pressure is provided for the shutdown of the circulating hydrogen subunit, and especially when the reaction unit decreases the pressure of the reaction unit to 0.5-1.0 MPa at a rate of 0.5-1.5 MPa / h, the shutdown of the circulating hydrogen subunit can be accelerated, which helps to safely shutdown the ebullated bed-fixed bed system.

[0092] According to a preferred embodiment of the present application, in step (5), the pressure relief conditions of the reaction unit include: pressure relief at a rate of 0.5-2.0 MPa / h to 0.05-0.3 MPa; preferably, pressure relief at a rate of 0.5-1.0 MPa / h to 0.1-0.2 MPa. With the foregoing embodiment, the required pressure for open-loop displacement of the gas phase in the reaction unit by inert gas is provided, and especially when the reaction unit is pressure relieved at a rate of 0.5-1.0 MPa / h to 0.1-0.2 MPa, the efficiency of open-loop displacement of the gas phase in the reaction unit by inert gas can be effectively improved, and the ebullated bed-fixed bed system can be safely shut down.

[0093] In step (5), the kind of the inert gas is not particularly limited according to the present application, and is a routine selection for those skilled in the art. According to a preferred embodiment of the present application, the inert gas is selected from any one of nitrogen, helium, neon, argon, krypton, xenon or radon, and is preferably nitrogen. With the foregoing embodiment, the gas phase in the reaction unit can be better displaced, and the ebullated bed-fixed bed system can be safely shut down.

[0094] According to a preferred embodiment of the present application, in step (5), the inert gas from the inert gas unit is used to open-loop displace the gas phase in the reaction unit, and the specific method is as follows: the reaction unit is pressurized to 0.3-2.0 MPa, and then the reaction unit is pressurized again after the separation unit is pressure relieved to 0.05-0.20 MPa, and the above process is repeated for 2-10 times. With the foregoing embodiment, the displacement efficiency of the inert gas for open-loop displacement of the gas phase in the reaction unit can be effectively improved, the displacement standard can be reached, the ebullated bed-fixed bed shutdown process can be combined with each other, and the ebullated bed-fixed bed system can be safely shut down.

[0095] In step (5), the feed amount of the inert gas is not particularly limited according to the present application, and can be reasonably selected by those skilled in the art as required, as long as the gas phase in the reaction unit can be completely displaced. According to a preferred embodiment of the present application, the inert gas from the inert gas unit is used to open-loop displace the gas phase in the reaction unit, and the specific method is as follows: the reaction unit is pressurized to 0.5-0.8 MPa, and then the reaction unit is pressurized again after the separation unit is pressure relieved to 0.05-0.10 MPa, and the above process is repeated for 2-5 times. With the foregoing embodiment, the efficiency of the inert gas for open-loop displacement of the gas phase in the reaction unit can be further improved, the displacement standard can be reached more quickly, the ebullated bed-fixed bed shutdown process can be combined with each other, and the ebullated bed-fixed bed system can be safely shut down.

[0096] According to a preferred embodiment of the present application, in step (5), the inert gas from the inert gas unit is used to replace the gas phase in the reaction unit, and the replacement is qualified when the content of hydrocarbon + hydrogen is less than 0.2 vol%, and the content of H2S is less than 10 mL / m 3 .

[0097] According to a third aspect of the present application, the present application provides an application of the shutdown method of the ebullated bed-fixed bed system according to the first aspect of the present application or the ebullated bed-fixed bed system according to the second aspect of the present application in hydrogenation of raw oil, preferably one or more of residual oil, heavy oil, pitch, coal tar and catalytic oil slurry.

[0098] The specific embodiments of the present application are described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the embodiments of the present application, and are not used to limit the embodiments of the present application.

[0099] In the following examples, the shutdown time is obtained by subtracting the time point when the recording device starts to reduce the temperature, the amount and the pressure from the time point when the inert replacement is qualified;

[0100] The test method for the replacement qualification of each step is as follows:

[0101] Distillation amount: SH / T 0165-1992 (2006) High vacuum distillation method for determination of petroleum products in high boiling range;

[0102] Viscosity: GB / T 11137 Determination of kinematic viscosity of dark petroleum products (upward flow method) and calculation of dynamic viscosity;

[0103] Hydrocarbon + hydrogen: ASTM D1946 Standard practice for gas chromatographic analysis of modified gases;

[0104] H2S content: MT 51-1994 Hydrogen sulfide detection tube;

[0105] Residual oil is from an atmospheric distillation unit;

[0106] Straight-run wax oil is from a conventional distillation unit, and the distillation range is 250-530°C;

[0107] Straight-run diesel oil is from a conventional distillation unit, and the distillation range is 195-390.

[0108] Example 1

[0109] The operating pressure of the reaction unit is 17 MPa, the feedstock subunit is at 100% load, the outlet temperature of the heat exchange subunit is 377°C, the outlet temperature of the ebullated bed reactor subunit is 405°C, the outlet temperature of the fixed bed reactor subunit is 413°C, and the temperature of the material entering the fractionation subunit of the separation subunit is 347°C; the product of the fractionation subunit is normally sent out of the system; the amount of circulating hydrogen in the circulating hydrogen subunit is 275 kNm 3 / h; the amount of fresh hydrogen in the fresh hydrogen subunit is 87 kNm 3 / h.

[0110] The ebullated bed-fixed bed system shown in FIG. 1 is used for shutdown, and the specific operation process is as follows: Figure 1

[0111] (1) The feedstock subunit, the heat exchange subunit, the ebullated bed reactor subunit, the fixed bed reactor subunit, and the separation subunit are simultaneously reduced in temperature at a rate of 8°C / h through the heat exchange subunit to an average temperature of 350°C in the ebullated bed reactor subunit and the fixed bed reactor subunit, the feed of residual oil is gradually reduced at a rate of 8 t / h through the feedstock subunit to 60% by weight of the design load, and the pressure of the reaction unit is reduced at a rate of 0.5 MPa / h through the fresh hydrogen subunit and the separation subunit to 10 MPa;

[0112] (2) The residual oil in the feedstock subunit, the heat exchange subunit, the ebullated bed reactor subunit, the fixed bed reactor subunit, and the separation subunit is replaced by straight-run wax oil through the oil injection pipeline at the inlet of the feedstock subunit, the feed of straight-run wax oil is gradually increased at a rate of 100 t / h to 60% by weight of the design load, and the feed of residual oil is proportionally reduced at a rate of 100 t / h to 0% by weight of the design load, until the residual oil is completely replaced by straight-run wax oil, the replaced residual oil is discharged to the system through the discharge pipeline at the outlet of the fractionation subunit, and the straight-run wax oil is recycled to the inlet of the feedstock subunit through the recycle pipeline at the outlet of the fractionation subunit, after 4 h of closed-loop circulation, the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit is reduced at a rate of 5°C / h to 280°C, and the pressure of the reaction unit is reduced at a rate of 0.5 MPa / h to 8 MPa;

[0113] ​(3) through the raw material sub-unit entrance of the injection oil pipeline straight diesel oil open replacement of raw material sub-unit, heat exchange sub-unit, boiling bed reactor sub-unit, fixed bed reactor sub-unit and separation sub-unit in straight wax oil, gradually increase the feed rate of straight diesel oil to 60% by weight of the design load at the speed of 100 t / h, while reducing the feed rate of straight wax oil by 0% by weight of the design load at the speed of 100 t / h, while replacing, the average temperature of the boiling bed reactor sub-unit and the fixed bed reactor sub-unit is reduced to 170℃ at the speed of 5℃ / h, until the straight wax oil is completely replaced by straight diesel oil, the straight wax oil after replacement is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, and the detection shows that the viscosity of the hot low oil and the hydrogenated atmospheric residue at 50℃ is 10mm 2 / s, the straight diesel oil open replacement of straight wax oil is qualified, and the straight diesel oil is recycled to the inlet of the raw material sub-unit through the circulating pipeline at the outlet of the fractionation unit for 4h;

[0114] (4) through the raw material sub-unit entrance of the injection oil pipeline straight diesel oil open replacement of raw material sub-unit, heat exchange sub-unit, boiling bed reactor sub-unit, fixed bed reactor sub-unit and separation sub-unit in straight wax oil, gradually increase the feed rate of straight diesel oil to 60% by weight of the design load at the speed of 100 t / h, while reducing the feed rate of straight wax oil by 0% by weight of the design load at the speed of 100 t / h, while replacing, the average temperature of the boiling bed reactor sub-unit and the fixed bed reactor sub-unit is reduced to 170℃ at the speed of 5℃ / h, until the straight wax oil is completely replaced by straight diesel oil, the straight wax oil after replacement is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, and the detection shows that the viscosity of the hot low oil and the hydrogenated atmospheric residue at 50℃ is 10mm 3 / s, the straight diesel oil open replacement of straight wax oil is qualified, and the straight diesel oil is recycled to the inlet of the raw material sub-unit through the circulating pipeline at the outlet of the fractionation unit for 4h;

[0115] (5) the raw material sub-unit stops feeding, the boiling bed reactor sub-unit is retreated with straight diesel oil at the speed of 20m 3 / h to the catalyst adding and discharging unit, after the oil is retreated, the raw material sub-unit, the heat exchange sub-unit, the boiling bed reactor sub-unit, the fixed bed reactor sub-unit and the separation sub-unit are increased to 4MPa at the speed of 0.5MPa / h, the fixed bed reactor sub-unit is circulated to discharge oil, the straight diesel oil in the fixed bed reactor sub-unit is separated into gas phase and liquid phase by the separation sub-unit, the gas phase is circulated to the inlet of the fixed bed reactor sub-unit and the inlet of the heat exchange sub-unit through the circulating hydrogen unit, and the liquid phase is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, and the circulating discharge oil is completed;

[0116] (6) When the average temperature of the fluidized bed reactor subunit and the fixed bed reactor subunit in the feed unit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit, and separation subunit is reduced to 40℃ at a rate of 1℃ / h, the circulating hydrogen unit is stopped. At the same time, the pressure is reduced to 0.5MPa at a rate of 0.5MPa / h, and then depressurized to 0.1MPa at a rate of 0.5MPa / h. Nitrogen gas from the inert gas unit is introduced to replace the gas phase in the feed unit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit, and separation subunit. The reaction unit is pressurized to 0.5MPa, and then depressurized to 0.05MPa from the separation subunit. The reaction unit is then pressurized again. This process is repeated twice until the gas phase is basically replaced by nitrogen gas. The replaced gas phase is discharged outside the system through the separation subunit. The volume percentage of hydrocarbon + hydrogen is detected to be 0.1v%, and the H2S content is 8mL / m. 3 The nitrogen purging was successful, and the plant was safely shut down for 12 days.

[0117] Example 2

[0118] Adopting attachment Figure 1 The fluidized bed-fixed bed system shown is to be shut down. The specific operation procedure is as follows:

[0119] (1) The feed subunit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit and separation subunit simultaneously reduce the average temperature of the fluidized bed reactor subunit and fixed bed reactor subunit to 360℃ at a rate of 10℃ / h through the heat exchange subunit, gradually reduce the feed rate of residue oil to 70% of the design load at a rate of 10t / h through the feed subunit, and reduce the pressure of the reaction unit to 12MPa at a rate of 1.0MPa / h through the new hydrogen unit and separation subunit;

[0120] (2) Through the oil injection pipeline at the inlet of the raw material sub-unit, straight-run wax oil is introduced to replace the residue oil in the raw material sub-unit, heat exchange sub-unit, fluidized bed reactor sub-unit, fixed bed reactor sub-unit and separation sub-unit. The feed rate of straight-run wax oil is gradually increased to 70% of the design load at a rate of 150t / h, while the feed rate of residue oil is proportionally reduced to 0% of the design load at a rate of 150t / h until the residue oil is completely replaced by straight-run wax oil. The replaced residue oil is discharged outside the system through the discharge pipeline at the outlet of the fractionation unit. After testing, the distillation rate of the hot low-temperature oil at 538℃ is 90%, and the open-circuit replacement of residue oil with straight-run wax oil is qualified. The straight-run wax oil is circulated through the circulation pipeline at the outlet of the fractionation unit to the inlet of the raw material sub-unit in a closed-circuit circulation for 6 hours. Then, the average temperature of the fluidized bed reactor sub-unit and the fixed bed reactor sub-unit is reduced to 290℃ at a rate of 10℃ / h, while the pressure of the reaction unit is reduced to 10MPa at a rate of 1.0MPa / h.

[0121] (3) through the raw material sub-unit entrance of the injection oil pipeline straight diesel oil open replacement of raw material sub-unit, heat exchange sub-unit, boiling bed reactor sub-unit, fixed bed reactor sub-unit and separation sub-unit in straight wax oil, gradually increase the feed rate of straight diesel oil to 70% of the design load at the speed of 150t / h, while reducing the feed rate of straight wax oil to 0% of the design load at the speed of 150t / h, while replacing, the average temperature of the boiling bed reactor sub-unit and the fixed bed reactor sub-unit is reduced to 200℃ at the speed of 8℃ / h, until the straight wax oil is completely replaced by straight diesel oil, the replaced straight wax oil is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, and the detection shows that the viscosity of the hot low oil and the hydrogenated atmospheric residue at 50℃ is 14mm 2 / s, the straight diesel oil open replacement of straight wax oil is qualified, and the straight diesel oil is recycled to the inlet of the raw material sub-unit through the circulating pipeline at the outlet of the fractionation unit for 6h;

[0122] (4) through the raw material sub-unit entrance of the injection oil pipeline straight diesel oil open replacement of raw material sub-unit, heat exchange sub-unit, boiling bed reactor sub-unit, fixed bed reactor sub-unit and separation sub-unit in straight wax oil, gradually increase the feed rate of straight diesel oil to 70% of the design load at the speed of 150t / h, while reducing the feed rate of straight wax oil to 0% of the design load at the speed of 150t / h, while replacing, the average temperature of the boiling bed reactor sub-unit and the fixed bed reactor sub-unit is reduced to 200℃ at the speed of 8℃ / h, until the straight wax oil is completely replaced by straight diesel oil, the replaced straight wax oil is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, and the detection shows that the viscosity of the hot low oil and the hydrogenated atmospheric residue at 50℃ is 14mm 3 / s, the straight diesel oil open replacement of straight wax oil is qualified, and the straight diesel oil is recycled to the inlet of the raw material sub-unit through the circulating pipeline at the outlet of the fractionation unit for 6h;

[0123] (4) through the raw material sub-unit entrance of the injection oil pipeline straight diesel oil open replacement of raw material sub-unit, heat exchange sub-unit, boiling bed reactor sub-unit, fixed bed reactor sub-unit and separation sub-unit in straight wax oil, gradually increase the feed rate of straight diesel oil to 70% of the design load at the speed of 150t / h, while reducing the feed rate of straight wax oil to 0% of the design load at the speed of 150t / h, while replacing, the average temperature of the boiling bed reactor sub-unit and the fixed bed reactor sub-unit is reduced to 200℃ at the speed of 8℃ / h, until the straight wax oil is completely replaced by straight diesel oil, the replaced straight wax oil is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, and the detection shows that the viscosity of the hot low oil and the hydrogenated atmospheric residue at 50℃ is 14mm 3 / s, the straight diesel oil open replacement of straight wax oil is qualified, and the straight diesel oil is recycled to the inlet of the raw material sub-unit through the circulating pipeline at the outlet of the fractionation unit for 6h;

[0124] (6) The raw material subunit, heat exchange subunit, ebullated bed reactor subunit, fixed bed reactor subunit and separation subunit are lowered in average temperature of the ebullated bed reactor subunit and fixed bed reactor subunit at a rate of 2°C / h to 45°C, and the cycle of the hydrogen unit is stopped, while the pressure is lowered at a rate of 1.0 MPa / h to 0.8 MPa, and then the pressure is released at a rate of 0.8 MPa / h to 0.15 MPa, nitrogen from the inert gas unit is used to replace the gas phase in the raw material subunit, heat exchange subunit, ebullated bed reactor subunit, fixed bed reactor subunit and separation subunit, the reaction unit is pressurized to 0.8 MPa, and then the pressure is released to 0.1 MPa from the separation subunit, and the reaction unit is pressurized again, and the process is repeated 5 times until the gas phase is basically replaced by nitrogen, the replaced gas phase is discharged to the outside of the system through the separation subunit, and the volume percentage of hydrocarbon + hydrogen is detected to be 0.15 v%, and the content of H2S is 9 mL / m 3 , the nitrogen replacement is qualified, the shutdown is safe, and the shutdown time is 13 days.

[0125] Example 3

[0126] The shutdown is performed by using the ebullated bed-fixed bed system as shown in the figure, and the specific operation process is as follows: Figure 1

[0127] (1) The raw material subunit, heat exchange subunit, ebullated bed reactor subunit, fixed bed reactor subunit and separation subunit are lowered in average temperature of the ebullated bed reactor subunit and fixed bed reactor subunit at a rate of 15°C / h to 370°C through the heat exchange subunit, the feed rate of residual oil is gradually lowered to 80% by weight of the design load at a rate of 15 t / h through the raw material subunit, and the pressure of the reaction unit is lowered to 14 MPa at a rate of 1.5 MPa / h through the new hydrogen unit and separation subunit;

[0128] (2) The residual oil in the raw material subunit, heat exchange subunit, ebullated bed reactor subunit, fixed bed reactor subunit and separation subunit is replaced by straight-run wax oil through the oil injection pipeline at the inlet of the raw material subunit, the feed rate of straight-run wax oil is gradually increased to 80% by weight of the design load at a rate of 200 t / h, and the feed rate of residual oil is proportionally reduced to 0% by weight of the design load at a rate of 200 t / h, until the residual oil is completely replaced by straight-run wax oil, the replaced residual oil is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, and the 538°C distillation amount of hot low-temperature oil is detected to be 95%, the straight-run wax oil open-loop replacement of residual oil is qualified, and the straight-run wax oil is circulated to the inlet of the raw material subunit through the circulation pipeline at the outlet of the fractionation unit for 8 h, then the average temperature of the ebullated bed reactor subunit and fixed bed reactor subunit is lowered to 300°C at a rate of 15°C / h, and the pressure of the reaction unit is lowered to 12 MPa at a rate of 1.5 MPa / h;

[0129] ​(3) through the raw material sub-unit entrance of the injection oil pipeline, straight-run diesel oil is introduced to replace straight-run wax oil in the raw material sub-unit, heat exchange sub-unit, ebullated bed reactor sub-unit, fixed bed reactor sub-unit and separation sub-unit, the feeding amount of straight-run diesel oil is gradually increased to 80% by weight of the design load at a speed of 200 t / h, while the feeding amount of straight-run wax oil is proportionally reduced to 0% by weight of the design load at a speed of 200 t / h, the average temperature of the ebullated bed reactor sub-unit and the fixed bed reactor sub-unit is reduced to 240°C at a speed of 10°C / h during the replacement, until the straight-run wax oil is completely replaced by straight-run diesel oil, the replaced straight-run wax oil is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, after detection, the viscosity of the hot low oil and the hydrogenated atmospheric residue at 50°C is 13 mm 2 / s, the straight-run diesel oil open replacement straight-run wax oil is qualified, the straight-run diesel oil is recycled to the inlet closed circuit of the raw material sub-unit through the recycling pipeline at the outlet of the fractionation unit for 8 h;

[0130] (4) through the raw material sub-unit entrance of the injection agent pipeline, flame retardant is introduced, the feeding amount of the flame retardant is 1.0% of the oil storage volume of the reaction unit, after sequentially flowing through the heat exchange sub-unit, the ebullated bed reactor sub-unit, the fixed bed reactor sub-unit and the separation unit, the flame retardant is recycled to the inlet closed circuit of the raw material sub-unit through the recycling pipeline at the outlet of the fractionation unit for 12 h, then the average temperature of the inlets of each unit is reduced to 150°C at a speed of 20°C / h, while the pressure is reduced to 2 MPa at a speed of 1.5 MPa / h, the ebullated bed reactor sub-unit is unloaded with catalyst to the catalyst loading and unloading unit at a speed of 24 m 3 / h, until the unloading of the catalyst is completed;

[0131] (5) the raw material sub-unit stops feeding, the ebullated bed reactor sub-unit is unloaded with straight-run diesel oil to the catalyst loading and unloading unit at a speed of 40 m 3 / h, after the oil unloading is completed, the raw material sub-unit, the heat exchange sub-unit, the ebullated bed reactor sub-unit, the fixed bed reactor sub-unit and the separation sub-unit are increased in pressure to 8 MPa at a speed of 1.5 MPa / h, the fixed bed reactor sub-unit is subjected to a circulating oil chasing process, the straight-run diesel oil in the fixed bed reactor sub-unit is separated into a gas phase and a liquid phase through the separation sub-unit, the gas phase is recycled to the inlet of the fixed bed reactor sub-unit and the inlet of the heat exchange sub-unit through the circulating hydrogen unit, and the liquid phase is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, the circulating oil chasing process is completed;

[0132] (6) When the average temperature of the fluidized bed reactor subunit and the fixed bed reactor subunit in the feed unit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit, and separation subunit is reduced to 50℃ at a rate of 3℃ / h, the circulating hydrogen unit is stopped. At the same time, the pressure is reduced to 1.0MPa at a rate of 1.5MPa / h, and then depressurized to 0.2MPa at a rate of 1.0MPa / h. Nitrogen gas from the inert gas unit is introduced to replace the gas phase in the feed unit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit, and separation subunit. The reaction unit is pressurized to 0.8MPa, and then depressurized to 0.08MPa from the separation subunit. The reaction unit is then pressurized again. This process is repeated 10 times until the gas phase is basically replaced by nitrogen gas. The replaced gas phase is discharged outside the system through the separation subunit. The volume percentage of hydrocarbon + hydrogen is detected to be 0.08v%, and the H2S content is 6mL / m. 3 After the nitrogen purging was completed successfully, the plant was safely shut down for 15 days.

[0133] Example 4

[0134] Adopting attachment Figure 1 The fluidized bed-fixed bed system shown is to be shut down. The specific operation procedure is as follows:

[0135] (1) The feed subunit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit and separation subunit simultaneously reduce the average temperature of the fluidized bed reactor subunit and fixed bed reactor subunit to 380℃ at a rate of 20℃ / h through the heat exchange subunit, gradually reduce the feed rate of residue oil to 100% of the design load at a rate of 15t / h through the feed subunit, and reduce the pressure of the reaction unit to 16MPa at a rate of 2.0MPa / h through the new hydrogen unit and separation subunit;

[0136] (2) Through the oil injection pipeline at the inlet of the raw material sub-unit, straight-run wax oil is introduced to replace the residue oil in the raw material sub-unit, heat exchange sub-unit, fluidized bed reactor sub-unit, fixed bed reactor sub-unit and separation sub-unit. The feed rate of straight-run wax oil is gradually increased to 100% of the design load at a rate of 200t / h, while the feed rate of residue oil is proportionally reduced to 0% of the design load at a rate of 200t / h, until the residue oil is completely replaced by straight-run wax oil. The replaced residue oil is discharged outside the system through the discharge pipeline at the outlet of the fractionation unit. After testing, the distillation yield of hot low-temperature oil at 538℃ is 88%, and the open-circuit replacement of residue oil with straight-run wax oil is qualified. The straight-run wax oil is circulated through the circulation pipeline at the outlet of the fractionation unit to the inlet of the raw material sub-unit in a closed-circuit circulation for 12h. Then, the average temperature of the fluidized bed reactor sub-unit and the fixed bed reactor sub-unit is reduced to 320℃ at a rate of 20℃ / h, while the pressure of the reaction unit is reduced to 14MPa at a rate of 2.0MPa / h.

[0137] (3) through the raw material sub-unit entrance of the injection oil pipeline, straight-run diesel oil is introduced to replace straight-run wax oil in the raw material sub-unit, heat exchange sub-unit, ebullated bed reactor sub-unit, fixed bed reactor sub-unit and separation sub-unit, the feeding amount of straight-run diesel oil is gradually increased to 100% of the design load at a rate of 200 t / h, while the feeding amount of straight-run wax oil is proportionally reduced to 0% of the design load at a rate of 200 t / h, and the average temperature of the ebullated bed reactor sub-unit and the fixed bed reactor sub-unit is reduced to 260°C at a rate of 20°C / h during the replacement, until the straight-run wax oil is completely replaced by straight-run diesel oil, and the replaced straight-run wax oil is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, after detection, the viscosity of the hot low oil and the hydrogenated atmospheric residue at 50°C is 16 mm 2 / s, the straight-run diesel oil open replacement straight-run wax oil is qualified, and the straight-run diesel oil is recycled to the inlet closed circuit of the raw material sub-unit through the recycling pipeline at the outlet of the fractionation unit for 12 h;

[0138] (4) through the raw material sub-unit entrance of the injection oil pipeline, straight-run diesel oil is introduced to replace straight-run wax oil in the raw material sub-unit, heat exchange sub-unit, ebullated bed reactor sub-unit, fixed bed reactor sub-unit and separation sub-unit, the feeding amount of straight-run diesel oil is gradually increased to 100% of the design load at a rate of 200 t / h, while the feeding amount of straight-run wax oil is proportionally reduced to 0% of the design load at a rate of 200 t / h, and the average temperature of the ebullated bed reactor sub-unit and the fixed bed reactor sub-unit is reduced to 260°C at a rate of 20°C / h during the replacement, until the straight-run wax oil is completely replaced by straight-run diesel oil, and the replaced straight-run wax oil is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, after detection, the viscosity of the hot low oil and the hydrogenated atmospheric residue at 50°C is 16 mm 3 / s, the straight-run diesel oil open replacement straight-run wax oil is qualified, and the straight-run diesel oil is recycled to the inlet closed circuit of the raw material sub-unit through the recycling pipeline at the outlet of the fractionation unit for 12 h;

[0139] (5) the raw material sub-unit stops feeding, the ebullated bed reactor sub-unit is unloaded at a rate of 50 m 3 / h, after the oil is unloaded, the raw material sub-unit, heat exchange sub-unit, ebullated bed reactor sub-unit, fixed bed reactor sub-unit and separation sub-unit are increased to 10 MPa at a rate of 2.0 MPa / h, the fixed bed reactor sub-unit is circulated to chase oil, the straight-run diesel oil in the fixed bed reactor sub-unit is separated into gas phase and liquid phase through the separation sub-unit, the gas phase is recycled to the inlet of the fixed bed reactor sub-unit and the inlet of the heat exchange sub-unit through the circulating hydrogen unit, and the liquid phase is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, and the circulation chasing oil is completed;

[0140] (6) When the average temperature of the fluidized bed reactor subunit and the fixed bed reactor subunit in the feed unit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit, and separation subunit is reduced to 60℃ at a rate of 5℃ / h, the circulating hydrogen unit is stopped. At the same time, the pressure is reduced to 2.0MPa at a rate of 2.0MPa / h, and then depressurized to 0.3MPa at a rate of 2.0MPa / h. Nitrogen gas from the inert gas unit is introduced to replace the gas phase in the feed unit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit, and separation subunit. The reaction unit is pressurized to 2.0MPa, and then depressurized to 0.2MPa from the separation subunit. The reaction unit is then pressurized again. This process is repeated 5 times until the gas phase is basically replaced by nitrogen gas. The replaced gas phase is discharged outside the system through the separation subunit. The volume percentage of hydrocarbon + hydrogen is detected to be 0.05v%, and the H2S content is 7mL / m. 3 After the nitrogen purging was completed successfully, the plant was safely shut down for 20 days.

[0141] Example 5

[0142] Adopting attachment Figure 1 The fluidized bed-fixed bed system shown is to be shut down. The specific operation procedure is as follows:

[0143] (1) The feed subunit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit and separation subunit simultaneously reduce the average temperature of the fluidized bed reactor subunit and fixed bed reactor subunit to 340℃ at a rate of 5℃ / h through the heat exchange subunit, gradually reduce the feed rate of residue oil to 60% of the design load at a rate of 5t / h through the feed subunit, and reduce the pressure of the reaction unit to 8MPa at a rate of 0.1MPa / h through the new hydrogen unit and separation subunit;

[0144] (2) Through the oil injection pipeline at the inlet of the raw material sub-unit, straight-run wax oil is introduced to replace the residue oil in the raw material sub-unit, heat exchange sub-unit, fluidized bed reactor sub-unit, fixed bed reactor sub-unit and separation sub-unit. The feed rate of straight-run wax oil is gradually increased to 60% of the design load at a rate of 50t / h, while the feed rate of residue oil is proportionally reduced to 0% of the design load at a rate of 50t / h until the residue oil is completely replaced by straight-run wax oil. The replaced residue oil is discharged outside the system through the discharge pipeline at the outlet of the fractionation unit. After testing, the distillation yield of hot low-temperature oil at 538℃ is 92%, and the open-circuit replacement of residue oil with straight-run wax oil is qualified. The straight-run wax oil is circulated through the circulation pipeline at the outlet of the fractionation unit to the inlet of the raw material sub-unit in a closed-circuit circulation for 2 hours. Then, the average temperature of the fluidized bed reactor sub-unit and the fixed bed reactor sub-unit is reduced to 260℃ at a rate of 5℃ / h, while the pressure of the reaction unit is reduced to 8MPa at a rate of 0.1MPa / h.

[0145] (3) Straight-run diesel oil is introduced through the oil injection pipeline at the inlet of the feed subunit to replace the straight-run wax oil in the feed subunit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit, and separation subunit. The feed rate of straight-run diesel oil is gradually increased to 60% of the design load at a rate of 50 t / h, while the feed rate of straight-run wax oil is proportionally reduced to 0% of the design load at a rate of 50 t / h. During the replacement, the average temperature of the fluidized bed reactor subunit and the fixed bed reactor subunit is reduced to 170℃ at a rate of 5℃ / h until all the straight-run wax oil is replaced with straight-run diesel oil. The replaced straight-run wax oil is discharged outside the system through the discharge pipeline at the outlet of the fractionation unit. The viscosity of the hot low-grade oil and the hydrogenated atmospheric residue oil at 50℃ is 16 mm. 2 / s, straight-run diesel oil is qualified after open-loop replacement of straight-run wax oil, and straight-run diesel oil is circulated through the circulation pipeline at the outlet of the fractionation unit to the inlet of the raw material sub-unit for 2 hours in a closed-loop circulation.

[0146] (4) Flame retardant is introduced through the injection pipeline at the inlet of the raw material subunit. The feed rate of the flame retardant is 0.3% of the oil volume of the reaction unit. It flows sequentially through the heat exchange subunit, the fluidized bed reactor subunit, the fixed bed reactor subunit, and the separation unit. After that, it circulates through the circulation pipeline at the outlet of the fractionation unit back to the inlet of the raw material subunit in a closed loop for 8 hours. Then, the average temperature at the inlet of each unit is reduced to 120℃ at a rate of 5℃ / h, and the pressure is reduced to 1MPa at a rate of 0.1MPa / h. The fluidized bed reactor subunit is at a rate of 14m 3 The catalyst is discharged to the catalyst addition and discharge unit at a rate of / h until the catalyst discharge is completed;

[0147] (5) The raw material sub-unit stops feeding, and the fluidized bed reactor sub-unit resumes feeding at a rate of 10m. 3 Straight-run diesel is returned to the catalyst addition and discharge unit at a rate of 0.1 MPa / h. After the oil is returned, the feed subunit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit and separation subunit increase the pressure to 1 MPa at a rate of 0.1 MPa / h. The fixed bed reactor subunit is circulated to remove oil. The straight-run diesel in the fixed bed reactor subunit is separated into gas phase and liquid phase by the separation subunit. The gas phase is circulated to the inlet of the fixed bed reactor subunit and the inlet of the heat exchange subunit through the circulating hydrogen unit. The liquid phase is discharged to the outside of the system through the discharge pipeline of the fractionation unit outlet, thus completing the circulation and removal of oil.

[0148] (6) The raw material subunit, heat exchange subunit, ebullated bed reactor subunit, fixed bed reactor subunit and separation subunit are lowered in average temperature of the ebullated bed reactor subunit and fixed bed reactor subunit at a rate of 1 ℃ / h to 30 ℃, and at the same time, the pressure is lowered at a rate of 0.5 MPa / h to 0.1 MPa, and then the pressure is released at a rate of 0.5 MPa / h to 0.05 MPa, nitrogen gas from the inert gas subunit is used to replace the gas phase in the raw material subunit, heat exchange subunit, ebullated bed reactor subunit, fixed bed reactor subunit and separation subunit, the reaction unit is pressurized to 0.3 MPa, and then the pressure is released to 0.01 MPa from the separation subunit, and then the reaction unit is pressurized again, and this is repeated 8 times until the gas phase is basically replaced by nitrogen gas, and the replaced gas phase is discharged to the outside of the system through the separation subunit, and the volume percentage of hydrocarbon + hydrogen is detected to be 0.12 v%, and the content of H2S is 6 mL / m 3 , the nitrogen replacement is qualified, the safety shutdown is completed, and the shutdown time is 22 days.

[0149] Comparative Example 1

[0150] The shutdown system is the same as that in Example 1, except that the shutdown method of the ebullated bed system is used for shutdown, and the specific operation process is as follows:

[0151] (1) The raw material subunit, heat exchange subunit, ebullated bed reactor subunit, fixed bed reactor subunit and separation subunit are lowered in average temperature of the ebullated bed reactor subunit and fixed bed reactor subunit at a rate of 8 ℃ / h to 350 ℃ through the heat exchange subunit, and the feed rate of residual oil is gradually lowered at a rate of 8 t / h through the raw material subunit to 60% by weight of the design load, and the pressure of the reaction unit is lowered at a rate of 0.5 MPa / h through the new hydrogen unit and separation subunit to 10 MPa;

[0152] (2) The residual oil in the raw material subunit, heat exchange subunit, ebullated bed reactor subunit, fixed bed reactor subunit and separation subunit is replaced by straight-run wax oil through the oil injection pipeline at the inlet of the raw material subunit, and the feed rate of straight-run wax oil is gradually increased at a rate of 100 t / h to 60% by weight of the design load, and at the same time, the feed rate of residual oil is proportionally reduced at a rate of 100 t / h to 0% by weight of the design load, until the residual oil is completely replaced by straight-run wax oil, and the replaced residual oil is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, and it is detected that the 538 ℃ distillation amount of hot low-temperature oil is 85%, the straight-run wax oil open-loop replacement of residual oil is qualified, and the straight-run wax oil is circulated to the inlet of the raw material subunit through the circulation pipeline at the outlet of the fractionation unit for 4 h, and then the average temperature of the ebullated bed reactor subunit and fixed bed reactor subunit is lowered at a rate of 5 ℃ / h to 280 ℃, and at the same time, the pressure of the reaction unit is lowered at a rate of 0.5 MPa / h to 8 MPa;

[0153] (3) Straight-run diesel oil is introduced through the oil injection pipeline at the inlet of the feed subunit to replace the straight-run wax oil in the feed subunit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit, and separation subunit. The feed rate of straight-run diesel oil is gradually increased to 60% of the design load at a rate of 100 t / h, while the feed rate of straight-run wax oil is proportionally reduced to 0% of the design load at a rate of 100 t / h. During the replacement, the average temperature of the fluidized bed reactor subunit and the fixed bed reactor subunit is reduced to 170℃ at a rate of 5℃ / h until all the straight-run wax oil is replaced with straight-run diesel oil. The replaced straight-run wax oil is discharged outside the system through the discharge pipeline at the outlet of the fractionation unit. The viscosity of the hot low-grade oil and the hydrogenated atmospheric residue oil at 50℃ is 12 mm. 2 / s, straight-run diesel oil is qualified after open-loop replacement of straight-run wax oil, and straight-run diesel oil is circulated through the circulation pipeline at the outlet of the fractionation unit to the inlet of the raw material sub-unit for 4 hours in a closed-loop circulation.

[0154] (4) Flame retardant is introduced through the injection pipeline at the inlet of the raw material subunit. The feed rate of the flame retardant is 0.5% of the oil volume of the reaction unit. It flows sequentially through the heat exchange subunit, the fluidized bed reactor subunit, the fixed bed reactor subunit, and the separation unit. After that, it circulates through the circulation pipeline at the outlet of the fractionation unit back to the inlet of the raw material subunit in a closed loop for 10 hours. Then, the average temperature of the fluidized bed reactor subunit and the fixed bed reactor subunit is reduced to 140℃ at a rate of 10℃ / h, while the pressure is reduced to 1.0MPa at a rate of 0.5MPa / h. The fluidized bed reactor subunit is at a pressure of 19m 3 The catalyst is discharged to the catalyst addition and discharge unit at a rate of / h until the catalyst discharge is completed;

[0155] (5) The raw material sub-unit stops feeding, and the fluidized bed reactor sub-unit operates at a rate of 20m... 3 The straight-run diesel fuel is returned to the catalyst addition and discharge unit at a rate of / h;

[0156] (6) When the average temperature of the fluidized bed reactor subunit and the fixed bed reactor subunit in the feed unit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit, and separation subunit is reduced to 40℃ at a rate of 1℃ / h, the circulating hydrogen unit is stopped. At the same time, the pressure is reduced to 0.5MPa at a rate of 0.5MPa / h, and then depressurized to 0.1MPa at a rate of 0.5MPa / h. Nitrogen gas from the inert gas unit is introduced to replace the gas phase in the feed unit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit, and separation subunit. The reaction unit is pressurized to 0.5MPa, and then depressurized to 0.05MPa from the separation subunit. The reaction unit is then pressurized again. This process is repeated 15 times until the gas phase is basically replaced by nitrogen gas. The replaced gas phase is discharged outside the system through the separation subunit. The volume percentage of hydrocarbon + hydrogen is detected to be 0.1v%, and the H2S content is 8mL / m. 3, nitrogen replacement qualified, safe shutdown, shutdown time 30 days.

[0157] The shutdown method of the ebullated bed system is used in the ebullated bed-fixed bed system provided by the present application, there is a problem that the fixed bed reactor subunit cannot be circulated or the circulation is not complete, the nitrogen replacement process is difficult to qualify, resulting in that the shutdown cannot be safe or the safe shutdown time is greatly prolonged.

[0158] Comparative Example 2

[0159] The shutdown system is the same as Example 1, except that the shutdown method of the fixed bed system is used for shutdown, and the specific operation process is as follows:

[0160] (1) The raw material subunit, heat exchange subunit, ebullated bed reactor subunit, fixed bed reactor subunit and separation subunit are simultaneously lowered in temperature at a rate of 8℃ / h through the heat exchange subunit to an average temperature of 350℃ in the ebullated bed reactor subunit and the fixed bed reactor subunit, the feed rate of the residual oil is gradually reduced to 60% by weight of the design load at a rate of 8t / h through the raw material subunit, and the reaction unit pressure is reduced to 10MPa at a rate of 0.5MPa / h through the mononitrogen unit and the separation subunit;

[0161] (2) The residual oil in the raw material subunit, heat exchange subunit, ebullated bed reactor subunit, fixed bed reactor subunit and separation subunit is replaced by straight-run wax oil introduced through the oil injection pipeline at the inlet of the raw material subunit, the feed rate of the straight-run wax oil is gradually increased to 60% by weight of the design load at a rate of 100t / h, while the feed rate of the residual oil is proportionally reduced to 0% by weight of the design load at a rate of 100t / h, until the residual oil is completely replaced by straight-run wax oil, the replaced residual oil is discharged to the outside of the system through the discharge pipeline at the outlet of the fractionation unit, and the hot low oil is detected to have a 538℃ distillation amount of 85%, the straight-run wax oil open-loop replacement of the residual oil is qualified, and the straight-run wax oil is circulated to the inlet of the raw material subunit through the circulation pipeline at the outlet of the fractionation unit for 4h, then the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit is lowered to 280℃ at a rate of 5℃ / h, and the reaction unit pressure is reduced to 8MPa at a rate of 0.5MPa / h;

[0162] (3) Straight-run diesel oil is introduced through the oil injection pipeline at the inlet of the feed subunit to replace the straight-run wax oil in the feed subunit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit, and separation subunit. The feed rate of straight-run diesel oil is gradually increased to 60% of the design load at a rate of 100 t / h, while the feed rate of straight-run wax oil is proportionally reduced to 0% of the design load at a rate of 100 t / h. During the replacement, the average temperature of the fluidized bed reactor subunit and the fixed bed reactor subunit is reduced to 170℃ at a rate of 5℃ / h until all the straight-run wax oil is replaced with straight-run diesel oil. The replaced straight-run wax oil is discharged outside the system through the discharge pipeline at the outlet of the fractionation unit. The viscosity of the hot low-grade oil and the hydrogenated atmospheric residue oil at 50℃ is 12 mm. 2 / s, straight-run diesel oil is qualified after open-loop replacement of straight-run wax oil, and straight-run diesel oil is circulated through the circulation pipeline at the outlet of the fractionation unit to the inlet of the raw material sub-unit for 4 hours in a closed-loop circulation.

[0163] (4) Flame retardant is introduced through the injection pipeline at the inlet of the raw material sub-unit. The feed rate of the flame retardant is 0.5% of the oil volume of the reaction unit. It flows through the heat exchange sub-unit, the fluidized bed reactor sub-unit, the fixed bed reactor sub-unit and the separation unit in sequence. Then it is circulated through the circulation pipeline at the outlet of the fractionation unit to the inlet of the raw material sub-unit for closed-loop circulation for 10 hours. Then the average temperature of the fluidized bed reactor sub-unit and the fixed bed reactor sub-unit is reduced to 140℃ at a rate of 10℃ / h.

[0164] (5) The feedstock subunit stops feeding and the fluidized bed reactor subunit and the fixed bed reactor subunit are circulated to remove oil. The straight-run diesel in the fluidized bed reactor subunit and the fixed bed reactor subunit is separated into gas phase and liquid phase by the separation subunit. The gas phase is circulated to the inlet of the fixed bed reactor subunit and the inlet of the heat exchange subunit through the circulating hydrogen unit, and the liquid phase is discharged to the outside of the system through the discharge pipeline of the fractionation unit outlet, thus completing the circulation of oil.

[0165] (6) When the average temperature of the fluidized bed reactor subunit and the fixed bed reactor subunit in the feed unit, heat exchange subunit, fluidized bed reactor subunit, and separation subunit is reduced to 40℃ at a rate of 1℃ / h, the circulating hydrogen unit is stopped. At the same time, the pressure is reduced to 0.5MPa at a rate of 0.5MPa / h, and then depressurized to 0.1MPa at a rate of 0.5MPa / h. Nitrogen gas from the inert gas unit is introduced to replace the gas phase in the feed unit, heat exchange subunit, fluidized bed reactor subunit, fixed bed reactor subunit, and separation subunit. The reaction unit is pressurized to 0.5MPa, and then depressurized to 0.05MPa from the separation subunit. The reaction unit is then pressurized again. This process is repeated 20 times until the gas phase is basically replaced by nitrogen gas. The replaced gas phase is discharged outside the system through the separation subunit. The volume percentage of hydrocarbon + hydrogen is detected to be 0.1v%, and the H2S content is 8mL / m. 3, nitrogen replacement is qualified, safe shutdown, shutdown time is 30 days.

[0166] The shutdown method of the fixed bed system is used in the boiling bed-fixed bed system provided by the present application, the boiling bed reactor subunit cannot be oil-retired, resulting in that the nitrogen replacement of the reaction unit is not thorough, the replacement is not qualified in a relatively short time, and the shutdown time is greatly prolonged or even cannot be safely shut down.

[0167] According to examples 1-5 and comparative examples 1-2, the boiling bed-fixed bed system provided by the present application can realize safe and reliable shutdown by using the shutdown method of the boiling bed-fixed bed system provided by the present application, and can effectively shorten the shutdown time by 3-15 days.

[0168] The shutdown method of the boiling bed-fixed bed system provided by the present application combines the boiling bed shutdown process and the fixed bed shutdown process for the first time, fills the gap of the existing shutdown method, has the characteristics of safety and reliability, environmental protection, and strong operability, fully considers the shutdown characteristics of the boiling bed process and the fixed bed process, fully identifies the connection and potential risks of each step of the boiling bed-fixed bed process, effectively avoids the influence of the shutdown oil in the boiling bed reactor on the fixed bed circulating oil, and realizes the effective connection of the shutdown process when the two processes are combined.

[0169] The above describes the preferred embodiments of the present application, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be considered as disclosed by the present application, and all belong to the protection scope of the present application.

Claims

1. An ebullated bed - fixed bed system, characterized in that, The system comprises a reaction unit and a fractionation unit arranged in series along the flow direction of the raw material; The reaction unit comprises a raw material subunit, a heat exchange subunit, a boiling bed reactor subunit, a fixed bed reactor subunit and a separation subunit arranged in series along the flow direction of the raw material; The raw material subunit is configured to provide raw oil to the reaction unit, and the raw material subunit is provided with an oil injection pipeline and an agent injection pipeline, the oil injection pipeline is configured to inject shutdown oil into the reaction unit, and the agent injection pipeline is configured to inject functional agent into the reaction unit; The heat exchange subunit is configured to control the temperature of the reaction unit; The boiling bed reactor subunit is configured to receive materials from the heat exchange subunit; The fixed bed reactor subunit comprises at least one fixed bed reactor configured to receive materials from the boiling bed reactor subunit; The separation subunit is configured to separate materials from the fixed bed reactor subunit; The fractionation unit is provided with a circulation pipeline and a discharge pipeline, each of which is configured to circulate the system and discharge the materials, and the circulation pipeline is in communication with the inlet of the raw material subunit; The boiling bed-fixed bed system further comprises: A catalyst adding and discharging unit configured to receive catalyst and shutdown oil from the boiling bed reactor subunit, and the outlet of the boiling bed reactor subunit is in communication with the inlet of the catalyst adding and discharging unit; A circulating hydrogen unit configured to provide circulating hydrogen to the reaction unit, the outlet of the separation subunit is in communication with the inlet of the circulating hydrogen unit, and the outlet of the circulating hydrogen unit is in communication with the inlet of the fixed bed reactor subunit and the inlet of the heat exchange subunit, respectively; A fresh hydrogen unit configured to provide fresh hydrogen required by the reaction unit and control the pressure of the reaction unit, and the outlet of the fresh hydrogen unit is in communication with the inlet of the fixed bed reactor subunit and the inlet of the heat exchange subunit, respectively; An inert gas unit configured to provide inert gas to replace the gas phase in the reaction unit, and the outlet of the inert gas unit is in communication with the inlet of the fixed bed reactor subunit and the inlet of the heat exchange subunit, respectively.

2. The ebullated bed - fixed bed system of claim 1, wherein, The fixed bed reactor subunit comprises 3-5 fixed bed reactors.

3. The ebullated bed - fixed bed system of claim 1, wherein, The fixed bed reactors are connected in series.

4. A method for shutting down the system of claim 1, characterized in that, The shutdown method comprises: (1) reducing the temperature, quantity and pressure of the reaction unit; (2) introducing shutdown oil through the oil injection pipeline to replace the raw oil in the reaction unit, and the replaced raw oil is discharged to the outside of the system through the discharge pipeline of the fractionation unit outlet, and after replacement, the shutdown oil is circulated to the inlet of the raw material subunit through the circulation pipeline of the fractionation unit outlet for closed loop circulation, and the temperature and pressure of the reaction unit are reduced; (3) injecting functional agent into the raw material subunit through the agent injection pipeline, and circulating to the inlet of the raw material subunit through the circulation pipeline of the fractionation unit outlet for closed loop circulation, and the temperature and pressure of the reaction unit are reduced, and the boiling bed reactor subunit is unloaded to the catalyst adding and discharging unit; (4) The raw material subunit stops feeding, the boiling bed reactor subunit retreats to stop the oil to the catalyst plus the unit, the reaction unit increases the pressure, the fixed bed reactor subunit's stop oil is separated into gas phase and liquid phase through the separation subunit, the gas phase is recycled to the fixed bed reactor subunit inlet and the heat exchange subunit inlet through the circulating gas unit, and the liquid phase is discharged to the outside of the system through the discharge pipeline of the fractionation unit outlet; (5) The reaction unit is cooled and decompressed in circulation, the circulating gas unit is stopped, the reaction unit is decompressed, and the gas phase in the reaction unit is replaced by inert gas from the inert gas unit, and the replaced gas phase is discharged to the outside of the system through the separation subunit, and the replacement is completed after being qualified.

5. The method of claim 4, wherein, In step (1), The reaction unit is cooled through the heat exchange subunit, reduced in quantity through the raw material subunit, and decompressed through the new gas unit and the separation subunit; The conditions for cooling the reaction unit include: The average temperature of the boiling bed reactor subunit and the fixed bed reactor subunit is simultaneously reduced at a speed of 5-20 ℃ / h to 340-380 ℃; And / or The conditions for reducing the quantity of the reaction unit include: The quantity of the raw oil is reduced at a speed of 5-15 t / h to 60-100% of the design load by weight; And / or The conditions for decompressing the reaction unit include: The pressure of the reaction unit is reduced at a speed of 0.1-2.0 MPa / h to 8-16 MPa.

6. The method of claim 5, wherein, In step (1), The conditions for cooling the reaction unit include: The average temperature of the boiling bed reactor subunit and the fixed bed reactor subunit is simultaneously reduced at a speed of 8-15 ℃ / h to 350-370 ℃; and / or The conditions for reducing the quantity of the reaction unit include: The quantity of the raw oil is reduced at a speed of 8-15 t / h to 60-80% of the design load by weight; and / or The conditions for decompressing the reaction unit include: The pressure of the reaction unit is reduced at a speed of 0.5-1.5 MPa / h to 10-14 MPa.

7. The method of claim 4, wherein, In step (2), The specific way of replacing the raw oil of the reaction unit by the stop oil open circuit is: Wax oil replaces the raw oil: the wax oil is introduced into the reaction unit through the oil injection pipeline to replace the raw oil in open circuit, the replaced raw oil is discharged to the outside of the system through the discharge pipeline of the fractionation unit outlet, and after the replacement is qualified, the wax oil is recycled to the inlet of the raw material subunit through the circulation pipeline of the fractionation unit outlet to form a closed loop circulation, and the reaction unit is cooled and decompressed.

8. The method of claim 4, wherein, In step (2), The specific way of replacing the raw oil of the reaction unit by the stop oil open circuit also includes: Diesel oil replaces the wax oil: diesel oil is introduced into the reaction unit through the oil injection pipeline to replace the wax oil in open circuit, the reaction unit is cooled at the same time, the replaced wax oil is discharged to the outside of the system through the discharge pipeline of the fractionation unit outlet, and after the replacement is qualified, the diesel oil is recycled to the inlet of the raw material subunit through the circulation pipeline of the fractionation unit outlet to form a closed loop circulation, and the reaction unit is cooled.

9. The method of claim 7, wherein: The distillation range of the wax oil is 250-530 ℃; and / or The raw oil is selected from at least one of residual oil, pitch, coal tar, and catalytic slurry oil; and / or The wax oil is introduced into the reaction unit through the oil injection pipeline to replace the raw oil in open circuit, Specifically, the feed amount of the wax oil is increased, and the feed amount of the raw oil is reduced by the same proportion, the replaced raw oil is discharged to the outside of the system through the discharge pipeline of the outlet of the fractionation unit, and the raw oil in the reaction unit is replaced by the wax oil until the raw oil is completely replaced by the wax oil; and / or The replacement standard is that the amount of 538℃ distillate of the hot low-temperature separated oil is greater than or equal to 85%; and / or The closed-loop circulation time of the wax oil is 2-12h; and / or In the process of replacing the raw oil with the wax oil, the reaction unit is cooled in a programmed manner, and the conditions include: The average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit is reduced to 260-320℃ at a speed of 5-20℃ / h; and / or The pressure of the reaction unit is reduced to 8-14MPa at a speed of 0.1-2.0MPa / h.

10. The method of claim 9, wherein, the wax oil is selected from hydrocracked wax oil or straight-run wax oil; and / or the raw oil is selected from residual oil; and / or the wax oil is open-loop replaced with the raw oil of the reaction unit; and / or the feed amount of the wax oil is 60-100% by weight of the design load; the feed speed of the wax oil is 50-280t / h; and / or The replacement standard is that the amount of 538℃ distillate of the hot low-temperature separated oil is greater than or equal to 85%; and / or The closed-loop circulation time of the wax oil is 4-8h; and / or In the process of replacing the raw oil with the wax oil, the reaction unit is cooled in a programmed manner, and the conditions include: The average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit is reduced to 280-300℃ at a speed of 5-15℃ / h; and / or The pressure of the reaction unit is reduced to 8-12MPa at a speed of 0.5-1.5MPa / h.

11. The method of claim 10, wherein, the wax oil is selected from straight-run wax oil; and / or the feed amount of the wax oil is 60-80% by weight of the design load; and / or the feed speed of the wax oil is 75-280t / h.

12. The method of claim 8, wherein, the distillation range of the diesel oil is 195-390℃; and / or the wax oil of the reaction unit is open-loop replaced with the diesel oil, Specifically, the feed amount of the diesel oil is increased, and the feed amount of the wax oil is reduced by the same proportion, the replaced wax oil is discharged to the outside of the system through the discharge pipeline of the outlet of the fractionation unit, and the wax oil in the reaction unit is replaced by the diesel oil until the wax oil is completely replaced by the diesel oil; and / or The reaction unit is cooled to 170-260℃ while being open-loop replaced; and / or and / or The closed-loop circulation time of the diesel oil is 2-12h; The standard for substitution qualification is: the viscosity of hot low-bleed oil and hydrogenated atmospheric feed oil at 50℃ is ≥10mm 2 / s; and / or In the process of replacing the wax oil with the diesel oil, the reaction unit is cooled at a speed of 5-20℃ / h to reduce the average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit to 170-260℃.

13. The method of claim 12, wherein, the diesel oil is selected from any one of hydrocracked diesel oil, straight-run diesel oil or catalytic diesel oil; and / or the feed amount of the diesel oil is 60-100% by weight of the design load; the feed speed of the diesel oil is 50-280t / h; and / or ​ ​ ​ The reaction unit is cooled to 170-240℃ in the open displacement reaction unit; and / or The diesel closed loop cycle time is 4-8h; and / or In the diesel displacement wax oil process, the reaction unit cooling conditions include: The average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit is reduced to 170-240℃ at a rate of 5-10℃ / h.

14. The method of claim 4, wherein, In step (3), The functional injection agent includes a flame retardant; and / or The functional injection agent closed loop cycle time is 8-24h; and / or The reaction unit cooling conditions include: The average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit is reduced to 120-160℃ at a rate of 5-25℃ / h. and / or The reaction unit pressure reduction conditions include: The reaction unit pressure is reduced to 1-5MPa at a rate of 0.1-2.0MPa / h. and / or The boiling bed reactor subunit unloads catalyst at a rate of 14-48 m 3 / h.

15. The method of claim 14, wherein, In step (3), The functional injection agent feed amount is 0.3-2.0% of the reaction unit oil storage volume; and / or The functional injection agent closed loop cycle time is 10-12h; and / or The reaction unit cooling conditions include: The average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit is reduced to 140-150℃ at a rate of 10-20℃ / h; and / or The reaction unit pressure reduction conditions include: The reaction unit pressure is reduced to 1-2MPa at a rate of 0.5-1.5MPa / h. and / or The boiling bed reactor subunit unloads catalyst at a rate of 19-24 m 3 / h.

16. The method of claim 15, wherein, In step (3), the functional injection agent feed amount is 0.5-1.0% of the reaction unit oil storage volume.

17. The method of claim 4, wherein, In step (4), The velocity of the ebullated bed reactor subunit to the catalyst addition and removal unit is 10-50 m 3 / h; and / or The reaction unit pressure increase conditions include: The reaction unit pressure is increased to 1-10MPa at a rate of 0.1-2.0MPa / h.

18. The method of claim 17, wherein, In step (4), The velocity of the ebullated bed reactor subunit to the catalyst addition and removal unit is 20-40 m 3 / h; and / or The reaction unit pressure increase conditions include: The reaction unit pressure is increased to 4-8MPa at a rate of 0.5-1.5MPa / h.

19. The method of claim 4, wherein, In step (5), The reaction unit cycle cooling conditions include: The average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit is reduced to 30-60℃ at a rate of 1-5℃ / h. and / or The reaction unit cycle pressure reduction conditions include: The reaction unit pressure is reduced to 0.1-2.0MPa at a rate of 0.5-2.0MPa / h. and / or The reaction unit pressure relief conditions include: The pressure is relieved to 0.05-0.3MPa at a rate of 0.5-2.0MPa / h. and / or The inert gas is selected from any one of nitrogen, helium, neon, argon, krypton, xenon or radon; and / or The inert gas from the inert gas unit displaces the gas phase in the reaction unit, Specifically, the reaction unit is pressurized to 0.3-2.0MPa, and after the separation subunit is depressurized to 0.05-0.20MPa, the reaction unit is pressurized again, and this is repeated 2-10 times; and / or In step (5), The criteria for replacement qualification are: hydrocarbon + hydrogen < 0.2 v%, H2S < 10 mL / m 3 .

20. The method of claim 19, wherein, The reaction unit cycle cooling conditions include: The average temperature of the ebullated bed reactor subunit and the fixed bed reactor subunit is reduced to 40-50℃ at a rate of 1-3℃ / h. and / or The reaction unit cycle pressure reduction conditions include: ​ the pressure of the reaction unit is reduced to 0.5-1.0 MPa at a rate of 0.5-1.0 MPa / h; and / or the conditions under which the reaction unit is depressurized include: depressurization to 0.1-0.2 MPa at a rate of 0.5-1.0 MPa / h; and / or the inert gas is nitrogen; and / or the reaction unit is pressurized to 0.5-0.8 MPa and depressurized to 0.05-0.10 MPa.

21. Use of the ebullated bed-fixed bed system according to any one of claims 1 to 3 or the shutdown method of the ebullated bed-fixed bed system according to any one of claims 4 to 20 in the hydrogenation of a feedstock oil.

22. The use according to claim 21, wherein the feedstock oil is one or more of residual oil, pitch, coal tar, and catalytic slurry oil.

23. The use according to claim 21, wherein the feedstock oil is heavy oil.

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