A hydrogenation heat exchange process

Abstract

A hydrogenation heat exchange process, when the working load M in the wound tube heat exchanger satisfies the design load N between N60%≤M≤N110%, the raw oil and hydrogen are mixed and flow through two tube passes of the wound tube heat exchanger, and the hydrogen-oil ratio in each tube pass is 500-1100Nm 3 / m 3 When the working load M and the design load N satisfy N 30%≤M<N 60%, the hydrogen is divided into two paths. The first path of hydrogen is mixed with the raw oil and then flows through the first pipe pass. The hydrogen-oil ratio in the first pipe pass is 475~1050Nm 3 / m 3 ; The second hydrogen goes through the second tube pass, and the flow rate of hydrogen in the second tube pass is not less than 0.1m / s; when the working load M and the design load N meet M>N 110%, the raw oil and hydrogen are mixed and go through the two tube passes of the wound tube heat exchanger, and the hydrogen-oil ratio in each tube pass is 450~1000Nm 3 / m 3 Compared with the prior art, the present application can adapt to load fluctuations and realize the conversion of different processing technologies of hydrogen mixing before the furnace and hydrogen mixing after the furnace.

Description

Technical Field

[0001] The invention belongs to the technical field of heat exchange, and in particular relates to a hydrogenation heat exchange process. Background Art

[0002] Hydrotreating is one of the more important treatment methods for petroleum products. It refers to the removal of sulfur, nitrogen, oxygen and other heteroatoms and metal impurities in oil products under certain temperature, hydrogen partial pressure and catalyst conditions, saturating olefins and partially hydrogenating aromatics to improve the performance of oil products.

[0003] The process of hydrotreating is as follows: after the oil product is mixed with hydrogen, it is sent to a heating furnace to be heated to a specified temperature, and then enters a reactor equipped with a catalyst; after the reaction is completed, the hydrogen is separated in a separator and recycled through a compressor; the products are separated in a stabilization tower into hydrogen sulfide, ammonia, water, and a small amount of gaseous hydrogen produced by decomposition during the reaction.

[0004] Existing hydrogenation heat exchange systems and processes, such as the solutions disclosed in the invention patent application with application number CN202110477804.0, "Hydrogenation heat exchange system and heat exchange process using multi-stream wound tube heat exchanger" (application publication number CN113063309A), and the invention patent application with application number CN202110477790.2, "A heat exchange system and heat exchange process for hydrogenation process" (application publication number CN113267075A).

[0005] The working load of the heat exchanger in the existing hydrogenation heat exchange system generally needs to be maintained between 60% and 100% of the design load. When it is in the start-up stage or when the raw material supply is insufficient, it is difficult to maintain a working load above 60%. Low-load operation often leads to scaling and coking in the heat exchanger, making it difficult for the entire system to operate for a long time. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a hydrogenation heat exchange process that can adapt to load fluctuations in view of the current status of the prior art.

[0007] The technical solution adopted by the present invention to solve the above technical problems is: a hydrogenation heat exchange process, characterized in that:

[0008] A wound tube heat exchanger with one shell pass and two tube passes is used for heat exchange. The two tube passes are the first tube pass and the second tube pass. The heat exchange process is:

[0009] When the working load M and the design load N in the wound tube heat exchanger meet the first working condition of N 60% ≤ M ≤ N 110%, the raw oil and hydrogen are mixed and flow through the two tubes of the wound tube heat exchanger, and the hydrogen-oil ratio in each tube is 500-1100 Nm 3 / m 3;

[0010] When the working load M and the design load N in the wound tube heat exchanger meet the second working condition of N 30% ≤ M < N 60%, the hydrogen is divided into two paths. The first path of hydrogen is mixed with all the raw oil and then flows through the first tube pass. The hydrogen-to-oil ratio in the first tube pass is 475-1050Nm 3 / m 3 The second hydrogen gas flows through the second tube pass, and the flow rate of hydrogen gas in the second tube pass is not less than 0.1 m / s. The hydrogen-oil ratio in the hydrogenation reaction is determined by the performance of the catalyst. When the performance of the catalyst is constant, the processing of the crude oil is reduced, and the hydrogen gas can be reduced synchronously. Because the crude oil only flows through one tube pass under the second working condition, the hydrogen flow rate does not change much compared with the first working condition.

[0011] The "hydrogen" in the present application may be the circulating hydrogen output from the hydrogenation device (the circulating hydrogen may contain impurities), or the hydrogen directly connected from the outside.

[0012] When the working load M and the design load N in the wound tube heat exchanger meet the third working condition of M>N 110%, the raw oil and hydrogen are mixed and flow through the two tubes of the wound tube heat exchanger, and the hydrogen-oil ratio in each tube is 450~1000Nm 3 / m 3 .

[0013] In this application, the workload in the wound tube heat exchanger can be determined from the ratio of the amount of processed raw oil to the design value. In addition, under various working conditions, the pressure and temperature of the raw oil are generally slightly higher than the pressure and temperature of hydrogen.

[0014] In order to reduce the risk of scaling of the heat exchanger, preferably, when the wound tube heat exchanger is switched from high-load operation of M≥N 60% to low-load operation of M<N 60%, the first tube pass is cleaned first, specifically as follows: all the raw oil and part of the hydrogen are passed into the first tube pass, and part of the hydrogen with a flow rate of 0.1-0.7 m / s is passed into the second tube pass (Note: except for ensuring that there is hydrogen with a low flow rate of 0.1-0.7 m / s in the second tube pass, all other hydrogen is passed into the first tube pass, and the temperature and pressure of the raw oil and hydrogen remain unchanged), after maintaining for 48-72 hours, all the hydrogen is passed into the first tube pass, all the raw oil is input into the second tube pass, and after maintaining for 12-24 hours, the cleaning of the first tube pass is completed;

[0015] Then clean the second pipe side as follows: pass all the crude oil and part of the hydrogen into the second pipe side, pass part of the hydrogen with a flow rate of 0.1 to 0.7 m / s into the first pipe side (Note: in addition to ensuring that there is hydrogen with a low flow rate of 0.1 to 0.7 m / s in the first pipe side, all other hydrogen is passed into the second pipe side, and the temperature and pressure of the crude oil and hydrogen remain unchanged), maintain for 48 to 72 hours and then complete the cleaning of the second pipe side.

[0016] In the above scheme, preferably, a hydrogenation heat exchange system having the above-mentioned wound tube heat exchanger is used, and the hydrogenation heat exchange system also includes a raw oil main pipeline for conveying raw oil and a hydrogen main pipeline for conveying hydrogen.

[0017] The output end of the main raw oil pipeline is connected to the first raw oil pipeline and the second raw oil pipeline;

[0018] The output end of the hydrogen main pipeline is connected to a first hydrogen pipeline and a second hydrogen pipeline;

[0019] The first raw oil pipeline, the second raw oil pipeline, the first hydrogen pipeline, and the second hydrogen pipeline are all provided with a first valve for controlling flow;

[0020] The inlet end of the first pipe pass is connected to the outlet end of the first raw oil pipeline and the outlet end of the first hydrogen pipeline, and the inlet end of the second pipe pass is connected to the outlet end of the second raw oil pipeline and the outlet end of the second hydrogen pipeline;

[0021] When the coiled tube heat exchanger is in the first operating condition, all first valves are opened;

[0022] When the wound tube heat exchanger is in the second operating condition, the first valve on the first raw oil pipeline is opened, the first valve on the second raw oil pipeline is closed, and the first valves on the first and second hydrogen pipelines are both opened;

[0023] When the coiled tube heat exchanger is in the third operating condition, all first valves are opened.

[0024] To ensure the heat exchange effect, preferably, the heat exchange tubes of the wound tube heat exchanger are spirally wound layer by layer from the inside to the outside to form a multi-layer spiral tube, each layer of the spiral tube has a heat exchange tube for the first tube pass and the second tube pass, and the heat exchange tubes for the first and second tube passes are evenly distributed in each layer of the spiral tube. In this way, the shell side medium and the medium of each layer of the spiral tube can be evenly exchanged with each other, especially when the first tube pass is passed with crude oil and hydrogen, and only a small amount of hydrogen is passed in the second tube pass, the heat exchange effect can be effectively guaranteed.

[0025] Preferably, the outlet end of the first tube pass and the outlet end of the second tube pass are separated to form two paths;

[0026] Alternatively, the outlet end of the first tube pass and the outlet end of the second tube pass are combined into one.

[0027] Preferably, the outlet end of the first tube pass and the outlet end of the second tube pass are two independent and separate winding tube heat exchangers, and the hydrogenation heat exchange system further comprises:

[0028] A first raw oil bypass pipeline, whose input end is connected to the first raw oil pipeline and is located between the inlet end of the first raw oil pipeline and the first valve on the first raw oil pipeline; and whose output end is connected to the outlet end of the first pipeline pass;

[0029] A second raw oil bypass pipeline, whose input end is connected to the second raw oil pipeline and is located between the inlet end of the second raw oil pipeline and the first valve on the second raw oil pipeline; and whose output end is connected to the outlet end of the second pipeline;

[0030] The first feedstock oil bypass pipeline and the second feedstock oil bypass pipeline are both provided with a third valve for controlling the flow rate. In this way, the third valve can be controlled according to the outlet temperature of the tube side of the heat exchanger. For example, when the outlet temperature of the tube side of the heat exchanger is high, the corresponding third valve can be opened to mix the unheated low-temperature feedstock oil with the medium at the outlet of the tube side, thereby reducing the temperature of the medium at the outlet of the tube side.

[0031] Also preferably, when the outlet end of the first tube pass and the outlet end of the second tube pass are combined into one, the hydrogenation heat exchange system further comprises:

[0032] A third raw oil bypass pipeline, whose input end is connected to the above raw oil main pipeline, and whose output end is connected to a combined path of the outlet end of the first pipe pass and the outlet end of the second pipe pass;

[0033] And a third valve is provided on the third raw oil bypass pipeline.

[0034] In the above schemes, preferably, the hydrogenation heat exchange system also includes a heating furnace and a hydrogenation reactor connected to the output end of the heating furnace, the outlet end of the first tube side and the outlet end of the second tube side are connected to the input end of the above heating furnace, the inlet end of the shell side of the wound tube heat exchanger is connected to the output end of the above hydrogenation reactor, and the outlet end of the shell side of the wound tube heat exchanger is connected to the downstream equipment.

[0035] Preferably, it also includes a heating furnace bypass pipeline, whose input end is connected to the pipeline between the input end of the heating furnace and the outlet end of the tube side of the wound tube heat exchanger, and whose output end is connected to the pipeline between the output end of the heating furnace and the input end of the hydrogenation reactor; and a fourth valve for controlling the flow is provided on the heating furnace bypass pipeline and the pipeline between the input end of the heating furnace and the outlet end of the tube side of the wound tube heat exchanger. In this way, when the temperature of the medium at the outlet of the tube side is high, the heating furnace bypass pipeline can be directly used.

[0036] Preferably, when the outlet end of the first tube pass and the outlet end of the second tube pass are separated and form two paths, the two paths are connected to the input end of the heating furnace through their own pipelines, and the above-mentioned fourth valve is provided on both pipelines. There are also two bypass pipelines of the heating furnace, and both are provided with a fourth valve. The input ends of the two bypass pipelines of the heating furnace are respectively connected to the corresponding two pipelines, and the output ends are connected to the pipeline between the output end of the heating furnace and the input end of the hydrogenation reactor. In this way, when the temperature of the medium at the outlet of the tube pass is high, the bypass pipeline of the heating furnace can be directly used. In this way, the conversion of different processing technologies of hydrogen mixing before the furnace and hydrogen mixing after the furnace can be realized according to the working conditions and the different processed oil products, and the advantages of the two hydrogenation processes can be taken into account, making the production more flexible and more adaptable.

[0037] Compared with the prior art, the advantages of the present invention are: by designing the heat exchange process so that when the heat exchanger is in normal working condition (i.e., the first working condition) or high load working condition (i.e., the third working condition), the raw oil and hydrogen are mixed and go through the two tubes of the heat exchanger; when the heat exchanger is in low load working condition (i.e., the second working condition), the required minimum flow rate requirement is achieved by adjusting the flow rate of the gas-liquid phase in different tubes, such as the raw oil and the first hydrogen are mixed and go through the first tube, and the second hydrogen goes through the second tube. Since all the raw oil goes through the first tube, the oil-gas mixed feed flow rate entering the heat exchanger can be guaranteed to be between 60% and 110% of the normal design, which solves the problem of low load and long cycle operation, and guarantees the flow rate and maintains the heat exchange efficiency of the heat exchanger; since hydrogen passes through the second tube, it effectively avoids the damage to the heat exchanger caused by the long-term high external pressure and high temperature working condition when there is no medium in a tube of the multi-stream heat exchanger. And the present application can realize the conversion of different processing technologies of hydrogen mixing before the furnace and hydrogen mixing after the furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0039] Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0040] Figure 3 This is a schematic diagram of the structure of the third embodiment of the present invention. DETAILED DESCRIPTION

[0041] The present invention is further described in detail below with reference to the accompanying drawings.

[0042] Embodiment 1:

[0043] like Figure 1As shown, a preferred embodiment 1 of a hydrogenation heat exchange process of the present invention is shown, and the process adopts a hydrogenation heat exchange system, which includes a wound tube heat exchanger 1, a raw oil main pipeline 2 for conveying raw oil, a hydrogen main pipeline 3 for conveying hydrogen, a first raw oil bypass pipeline 51, a second raw oil bypass pipeline 52, a heating furnace 6, a hydrogenation reactor 7 and a heating furnace bypass pipeline 8.

[0044] The main feedstock oil pipeline 2 and the main hydrogen pipeline 3 are both provided with a second valve 42 for controlling the flow rate. The output end of the main feedstock oil pipeline 2 is connected to the first feedstock oil pipeline 21 and the second feedstock oil pipeline 22. The output end of the main hydrogen pipeline 3 is connected to the first hydrogen pipeline 31 and the second hydrogen pipeline 32. The first feedstock oil pipeline 21, the second feedstock oil pipeline 22, the first hydrogen pipeline 31, and the second hydrogen pipeline 32 are both provided with a first valve 41 for controlling the flow rate.

[0045] The wound tube heat exchanger 1 has a shell side and two tube sides, the two tube sides are the first tube side 11 and the second tube side 12, the inlet end of the first tube side 11 is connected to the outlet end of the first raw oil pipeline 21 and the outlet end of the first hydrogen pipeline 31, and the inlet end of the second tube side 12 is connected to the outlet end of the second raw oil pipeline 22 and the second hydrogen pipeline 32. The outlet end of the first tube side 11 and the outlet end of the second tube side 12 are separated and form two paths. In this embodiment, the heat exchange tubes of the wound tube heat exchanger 1 are spirally wound layer by layer from the inside to the outside to form a multi-layer spiral tube, and each layer of the spiral tube has the heat exchange tubes of the first tube side 11 and the second tube side 12, and the number of heat exchange tubes of the first and second tube sides is the same and is evenly distributed alternately in each layer of the spiral tube.

[0046] The input end of the first raw oil bypass pipeline 51 is connected to the first raw oil pipeline 21 and is located between the inlet end of the first raw oil pipeline 21 and the first valve 41 on the first raw oil pipeline 21. The output end of the first raw oil bypass pipeline 51 is connected to the outlet end of the first pipe pass 11. The input end of the second raw oil bypass pipeline 52 is connected to the second raw oil pipeline 22 and is located between the inlet end of the second raw oil pipeline 22 and the first valve 41 on the second raw oil pipeline 22. The output end of the second raw oil bypass pipeline 52 is connected to the outlet end of the second pipe pass 12. At the same time, the first raw oil bypass pipeline 51 and the second raw oil bypass pipeline 52 are both provided with a third valve 43 for controlling the flow rate.

[0047] The two pipelines coming out of the two tubes of the wound tube heat exchanger 1 are merged into one and then connected to the input end of the heating furnace 6, the output end of the heating furnace 6 is connected to the input end of the hydrogenation reactor 7, the output end of the hydrogenation reactor 7 is connected to the inlet end of the shell side of the wound tube heat exchanger 1, and the outlet end of the shell side of the wound tube heat exchanger 1 is connected to the downstream equipment. The downstream equipment is the existing technology, including a hot high-pressure separation tank, a hot low-pressure separation tank, an air cooler, a cold low-pressure separation tank, etc., which will not be described in detail here.

[0048] The input end of the heating furnace bypass pipeline 8 is connected to the pipeline between the input end of the heating furnace 6 and the outlet end of the tube side of the wound tube heat exchanger 1, and the output end is connected to the pipeline between the output end of the heating furnace 6 and the input end of the hydrogenation reactor 7; and the fourth valve 44 for controlling the flow rate is provided on the heating furnace bypass pipeline 8 and the pipeline between the input end of the heating furnace 6 and the outlet end of the tube side of the wound tube heat exchanger 1. The fourth valve 44 on the pipeline between the input end of the heating furnace 6 and the outlet end of the tube side of the wound tube heat exchanger 1 is located between the input end of the heating furnace 6 and the input end of the heating furnace bypass pipeline 8.

[0049] The heat exchange process of this embodiment is as follows:

[0050] When the working load M and the design load N in the wound tube heat exchanger 1 meet the first working condition of N 60% ≤ M ≤ N 110%, all first valves 41 are opened, and the raw oil and hydrogen are mixed and flow through the two tubes of the wound tube heat exchanger 1, and the hydrogen-to-oil ratio in each tube is 500-1100 Nm 3 / m 3 (Hydrogen oil ratio can be 500Nm 3 / m 3 、1100Nm 3 / m 3 Or any value between 500 and 1100, designed according to actual working conditions);

[0051] When the working load M and the design load N in the wound tube heat exchanger 1 meet the second working condition of N 30% ≤ M < N 60%, the first valve 41 on the first raw oil pipeline 21 is opened, the first valve 41 on the second raw oil pipeline 22 is closed, and the first valves 41 on the first and second hydrogen pipelines are opened, so that the hydrogen is divided into two paths. The first path of hydrogen is mixed with the raw oil and then flows through the first pipe 11, and the hydrogen-to-oil ratio in the first pipe 11 is 475-1050Nm 3 / m 3 (Hydrogen oil ratio can be 475Nm 3 / m 3 、1050Nm 3 / m 3or any value between 475 and 1050, specifically designed according to actual working conditions); the second hydrogen passes through the second pipe 12, and the flow rate of the hydrogen in the second pipe 12 is not less than 0.1 m / s;

[0052] When the working load M and the design load N in the wound tube heat exchanger 1 meet the third working condition of M>N 110%, all first valves 41 are opened, and the raw oil and hydrogen are mixed and flow through the two tubes of the wound tube heat exchanger 1, and the hydrogen-oil ratio in each tube is 450-1000Nm 3 / m 3 (Hydrogen oil ratio can be 450Nm 3 / m 3 、1000Nm 3 / m 3 Or any value between 450 and 1000, specifically designed according to the actual working conditions). Under the third working condition, in order to fully exchange heat, the feed oil bypass will be closed, and the hydrogen-to-oil ratio will decrease.

[0053] In the heat exchanger of the present application, the tube side inlet temperature is 110-160°C, the tube side outlet temperature is 320-380°C, the shell side inlet temperature is 360-420°C, the shell side outlet temperature is 220-260°C, and the operating pressure is 5-20MPa.

[0054] When the wound tube heat exchanger 1 is switched from high load (≥ N 60%) operation to low load (< N 60%) operation, the first tube side 11 is cleaned first, specifically as follows: all the raw oil and most of the hydrogen are passed into the first tube side 11, a small portion of hydrogen with a flow rate of 0.1-0.7 m / s is passed into the second tube side 12, and after maintaining for 48-72 hours, all the hydrogen is passed into the first tube side 11, all the raw oil is input into the second tube side 12, and after maintaining for 12-24 hours, the cleaning of the first tube side 11 is completed;

[0055] Then clean the second pipe side as follows: pass all the crude oil and most of the hydrogen into the second pipe side 12, pass a small portion of hydrogen with a flow rate of 0.1 to 0.7 m / s into the first pipe side 11, and complete the cleaning of the second pipe side 12 after maintaining for 48 to 72 hours.

[0056] Embodiment 2:

[0057] like Figure 2As shown, a preferred embodiment 2 of a hydrogenation heat exchange process of the present invention is shown. This embodiment is basically the same as the embodiment 1, except that in this embodiment, the outlet end of the first tube side 11 and the outlet end of the second tube side 12 are separated independently to form two paths, and the two paths are connected to the input end of the heating furnace 6 through their own pipelines, and the two pipelines are both provided with the above-mentioned fourth valve 44, and there are also two heating furnace bypass pipelines 8, and both are provided with the fourth valve 44, the input ends of the two heating furnace bypass pipelines 8 are respectively connected to the corresponding two pipelines, and the output ends are connected to the pipeline between the output end of the heating furnace 6 and the input end of the hydrogenation reactor 7.

[0058] Embodiment three:

[0059] like Figure 3 As shown, a preferred embodiment 3 of a hydrogenation heat exchange process of the present invention is shown. This embodiment is basically the same as the embodiment 1, except that in this embodiment, the outlet end of the first pipe side 11 and the outlet end of the second pipe side 12 are combined into one, and the combined pipeline is connected to the raw oil main pipeline 2 through a third raw oil bypass pipeline 53, and the third raw oil bypass pipeline 53 is provided with a third valve 43.

Claims

1. A hydrogenation heat exchange process, characterized in that: A wound tube heat exchanger (1) having a shell side and two tube sides is used for heat exchange, wherein the two tube sides are a first tube side (11) and a second tube side (12), and the heat exchange process is as follows: When the working load M and the design load N in the wound tube heat exchanger (1) satisfy the first working condition of N 60% ≤ M ≤ N 110%, the raw oil and hydrogen are mixed and flow through two tube passes of the wound tube heat exchanger (1), and the hydrogen-to-oil ratio in each tube pass is 500-1100 Nm 3 / m 3 ; When the working load M and the design load N in the wound tube heat exchanger (1) meet the second working condition of N 30% ≤ M < N 60%, the hydrogen is divided into two paths. The first path of hydrogen is mixed with all the raw oil and then flows through the first tube pass (11). The hydrogen-oil ratio in the first tube pass (11) is 475-1050Nm 3 / m 3 The second hydrogen gas flows through the second pipe (12), and the flow rate of the hydrogen gas in the second pipe (12) is not less than 0.1 m / s; When the working load M and the design load N in the wound tube heat exchanger (1) satisfy the third working condition of M>N 110%, the raw oil and hydrogen are mixed and flow through two tube passes of the wound tube heat exchanger (1), and the hydrogen-oil ratio in each tube pass is 450-1000 Nm 3 / m 3 ; The hydrogenation heat exchange process uses a hydrogenation heat exchange system having the above-mentioned wound tube heat exchanger (1), and the hydrogenation heat exchange system also includes a raw material oil main pipeline (2) for conveying raw material oil and a hydrogen main pipeline (3) for conveying hydrogen. The output end of the main raw oil pipeline (2) is connected to a first raw oil pipeline (21) and a second raw oil pipeline (22); The output end of the hydrogen main pipeline (3) is connected to a first hydrogen pipeline (31) and a second hydrogen pipeline (32); The first raw oil pipeline (21), the second raw oil pipeline (22), the first hydrogen pipeline (31), and the second hydrogen pipeline (32) are all provided with a first valve (41) for controlling flow rate; The inlet end of the first pipe side (11) is connected to the outlet end of the first raw oil pipeline (21) and the outlet end of the first hydrogen pipeline (31), and the inlet end of the second pipe side (12) is connected to the outlet end of the second raw oil pipeline (22) and the outlet end of the second hydrogen pipeline (32); When the coiled tube heat exchanger (1) is in a first operating state, each first valve (41) is opened; When the wound tube heat exchanger (1) is in the second operating state, the first valve (41) on the first raw oil pipeline (21) is opened, the first valve (41) on the second raw oil pipeline (22) is closed, and the first valves (41) on the first and second hydrogen pipelines are both opened; When the coiled tube heat exchanger (1) is in the third operating state, all first valves (41) are open.

2. The hydrogenation heat exchange process according to claim 1, characterized in that: When the wound tube heat exchanger (1) is switched from high load operation of M≥N60% to low load operation of M<N60%, the first tube side (11) is cleaned first, specifically as follows: all the raw oil and part of the hydrogen are passed into the first tube side (11), part of the hydrogen with a flow rate of 0.1 to 0.7 m / s is passed into the second tube side (12), and after maintaining for 48 to 72 hours, all the hydrogen is passed into the first tube side (11), all the raw oil is input into the second tube side (12), and after maintaining for 12 to 24 hours, the cleaning of the first tube side (11) is completed; Then, the second tube side (12) is cleaned as follows: all the crude oil and part of the hydrogen are introduced into the second tube side (12), part of the hydrogen with a flow rate of 0.1 to 0.7 m / s is introduced into the first tube side (11), and the cleaning of the second tube side (12) is completed after maintaining for 48 to 72 hours.

3. The hydrogenation heat exchange process according to claim 1, characterized in that: The heat exchange tubes of the wound tube heat exchanger (1) are spirally wound layer by layer from the inside to the outside to form a multi-layer spiral tube, each layer of the spiral tube has a first tube pass (11) and a second tube pass (12) heat exchange tube, and the first and second tube pass heat exchange tubes are evenly distributed in each layer of the spiral tube.

4. The hydrogenation heat exchange process according to claim 1, characterized in that: The outlet end of the first tube pass (11) and the outlet end of the second tube pass (12) are separated independently to form two paths; Alternatively, the outlet end of the first tube pass (11) and the outlet end of the second tube pass (12) are combined into one.

5. The hydrogenation heat exchange process according to claim 4, characterized in that: When the outlet end of the first tube pass (11) and the outlet end of the second tube pass (12) are separated to form two independent paths, the hydrogenation heat exchange system further comprises: A first raw oil bypass pipeline (51), whose input end is connected to the first raw oil pipeline (21) and is located between the inlet end of the first raw oil pipeline (21) and the first valve (41) on the first raw oil pipeline (21); and whose output end is connected to the outlet end of the first pipeline (11); A second raw oil bypass pipeline (52), whose input end is connected to the second raw oil pipeline (22) and is located between the inlet end of the second raw oil pipeline (22) and the first valve (41) on the second raw oil pipeline (22); and whose output end is connected to the outlet end of the second pipeline (12); The first crude oil bypass pipeline (51) and the second crude oil bypass pipeline (52) are both provided with a third valve (43) for controlling flow rate.

6. The hydrogenation heat exchange process according to claim 4, characterized in that: When the outlet end of the first tube side (11) and the outlet end of the second tube side (12) are combined into one path; the hydrogenation heat exchange system further comprises: A third crude oil bypass pipeline (53), whose input end is connected to the crude oil main pipeline (2), and whose output end is connected to a combined outlet of the first pipe pass (11) and the outlet of the second pipe pass (12); Furthermore, a third valve (43) is provided on the third raw oil bypass pipeline (53).

7. The hydrogenation heat exchange process according to any one of claims 4 to 6, characterized in that: The hydrogenation heat exchange system also includes a heating furnace (6), a hydrogenation reactor (7) connected to the output end of the heating furnace (6), the outlet end of the first tube side (11) and the outlet end of the second tube side (12) are connected to the input end of the above-mentioned heating furnace (6), the inlet end of the shell side of the wound tube heat exchanger (1) is connected to the output end of the above-mentioned hydrogenation reactor (7), and the outlet end of the shell side of the wound tube heat exchanger (1) is connected to the downstream equipment.

8. The hydrogenation heat exchange process according to claim 7, characterized in that: It also includes a heating furnace bypass pipeline (8), whose input end is connected to the pipeline between the input end of the heating furnace (6) and the outlet end of the tube side of the wound tube heat exchanger (1), and whose output end is connected to the pipeline between the output end of the heating furnace (6) and the input end of the hydrogenation reactor (7); and a fourth valve (44) for controlling the flow rate is provided on the heating furnace bypass pipeline (8) and on the pipeline between the input end of the heating furnace (6) and the outlet end of the tube side of the wound tube heat exchanger (1).

9. The hydrogenation heat exchange process according to claim 8, characterized in that: When the outlet end of the first pipe side (11) and the outlet end of the second pipe side (12) are independently separated to form two routes, the two routes are connected to the input end of the heating furnace (6) through their own pipelines, and the above-mentioned fourth valve (44) is provided on both pipelines. There are also two heating furnace bypass pipelines (8), and both are provided with the fourth valve (44). The input ends of the two heating furnace bypass pipelines (8) are respectively connected to the corresponding two pipelines, and the output ends are connected to the pipeline between the output end of the heating furnace (6) and the input end of the hydrogenation reactor (7).

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