Sulfidation method of fixed bed residue oil hydrogenation catalyst

Abstract

The present invention discloses a method for sulfurizing a fixed-bed residual oil hydrogenation catalyst. The method comprises: after completing the catalyst loading, air tightness inspection, and catalyst presulfurization preparation steps for the fixed-bed residual oil hydrogenation device, the reverse sulfurization process of the catalyst is started: first, a reverse full-cycle process of the start-up diesel is established, and then the diesel is presulfurized in a full cycle. When the reactor temperature is 230 to 260°C, the start-up diesel is switched to wax oil, and then the wax oil is presulfurized in a full cycle, and finally, fresh sulfur-containing wax oil is used for non-full cycle presulfurization. The sulfurization method of the present invention can shorten the catalyst sulfurization time, reduce the amount of sulfurizing agent, reduce equipment corrosion, and prevent the catalyst from being over-activated and coked in the initial stage, which causes the catalyst bed pressure drop to increase and the properties of the hydrogenation product to deteriorate.

Description

Technical Field

[0001] The invention relates to the technical field of residual oil hydrogenation, in particular to a sulfurization method of a fixed-bed residual oil hydrogenation catalyst. Background Art

[0002] Heavy oil refers to oil products with heavier fractions, generally referring to the residual oil fraction, which is the remaining part after the crude oil is subjected to atmospheric and vacuum distillation to remove the gasoline fraction, diesel fraction, vacuum distillate oil and other fractions. The physical and chemical properties of residual oil are characterized by high viscosity, many heteroatoms and low hydrogen-carbon ratio. It is one of the most difficult raw materials to process in the oil refining industry. The processing of residual oil is not only to crack it into low-boiling products, such as naphtha, middle distillate oil and vacuum gas oil, but also to increase its hydrogen-carbon ratio. At present, the developed residual oil processing processes mainly include hydrogenation and decarbonization. Compared with the coking process in the decarbonization process, the hydrogenation process can not only increase the yield of liquid products, but also remove heteroatoms therein, providing high-quality feed for downstream devices. Therefore, the hydrogenation unit has become the core unit of most oil refining enterprises.

[0003] Hydrogenation process is divided into four types according to the state of catalyst in the reactor: fixed bed, moving bed, ebullating bed and suspended bed. Fixed bed residue oil hydrogenation process technology has the advantages of high liquid product yield, good product quality, strong production flexibility, less waste and scrap, environmental friendliness, high return on investment, etc., and is being used more and more widely. At present, the combination of residue oil fixed bed hydrotreatment and catalytic cracking is the mainstream technology in China's residue oil hydrogenation and upgrading process technology.

[0004] Fixed bed residue oil hydrogenation technology has the characteristics of complex raw material composition, multiple reactors, and multiple catalyst brands, which determines that the start-up process will directly affect the operating performance, product quality and operation cycle of the device. The catalyst sulfidation step in the start-up process is particularly important. At present, the active metal components of residue oil hydroprocessing catalysts exist in an oxidized state during production, transportation and storage. Research and industrial practice have proved that the hydroprocessing catalyst has higher hydrogenation activity, stability and selectivity, stronger anti-toxicity, and longer life after sulfurization, so as to maximize the role of the hydrogenation catalyst. Therefore, the residue oil hydroprocessing catalyst must be sulfurized before use to improve the activity and stability of the catalyst.

[0005] Catalyst sulfidation can be divided into wet sulfidation and dry sulfidation. Dry sulfidation is carried out in the presence of hydrogen by directly injecting organic sulfides into a certain concentration of hydrogen sulfide or directly injecting them into the circulating hydrogen. Wet sulfidation is carried out in the presence of hydrogen by pre-sulfurizing distillate oil containing sulfides in liquid and semi-liquid phases.

[0006] There are many problems in the existing fixed-bed residue oil hydrogenation catalyst sulfurization process. For example, in order to ensure that the catalyst is completely sulfurized, an excessive amount of sulfurizing agent is injected into the reaction system, causing problems with the storage and safety of the sulfurizing agent, and the excessive hydrogen sulfide produced by the decomposition of the sulfurizing agent will corrode the equipment, especially the high-pressure air cooling, and the load of the subsequent desulfurization process will increase, directly affecting the complexity of the operation and economic benefits; in the early stage of the reaction, the over-activated catalyst has a high hydrogenation activity, which not only causes rapid coking on the catalyst surface, but also hydrogenates and saturates the aromatic components in the residue oil in large quantities. However, due to the low reaction temperature, the large-molecule asphaltene that is difficult to react cannot be converted into small molecules, destroying the colloidal system with aromatic components as solvent and colloidal asphaltene as solute, resulting in the precipitation of asphaltene, and foam entrainment at the hot high-pressure separator, which seriously affects the separation effect and system stability; due to the limited heat source of the device, it is difficult to heat up the reactor, and the constant temperature period during the high-temperature sulfurization process is too long, resulting in a long sulfurization time.

[0007] CN103059939A discloses a catalyst sulfurization method for a residue oil hydrogenation process. The method includes: 1) the residue oil hydroprocessing unit includes two rows of residue oil hydrogenation series reactors; 2) one row of reactors in the residue oil hydroprocessing unit operates normally, and the other row of reactors is ready for sulfurization and start-up; 3) the desulfurization rate of the circulating hydrogen desulfurization unit in the stably operated residue oil hydroprocessing unit is adjusted; 4) the hydrogen sulfide-containing gas discharged from the circulating hydrogen desulfurization unit of the stably operated residue oil hydroprocessing unit is introduced into a row of residue oil hydroprocessing unit reactors ready for sulfurization, and the row of residue oil hydroprocessing reactor devices is subjected to sulfurization operation; 5) sulfurization is performed according to the normal residue oil hydroprocessing unit dry / wet sulfurization conditions until the end. The application scenario of this method is limited. First, the device needs to be set up in a double series, and the two rows need to be staggered to stop and start, which is not suitable for single series devices and the same start and stop operation mode.

[0008] CN103100446A discloses a start-up sulfurization method for a hydrogenation device. The method comprises: first, a part of the circulating gas is heated by a heating furnace, and then a sulfurizing agent is introduced, the sulfurizing agent is decomposed to obtain hydrogen sulfide, and then the circulating gas rich in hydrogen sulfide is mixed with the second part of the circulating gas, and after reaching the expected temperature requirement, the catalyst bed is passed through, and the temperature is continued to rise after a large amount of hydrogen sulfide penetrates the catalyst bed, and the injection amount of the sulfurizing agent is adjusted according to the requirements of the hydrogen sulfide content, and the ratio of the two parts of the circulating gas is adjusted according to the temperature requirements, and the sulfurization is completed according to the heating rate and constant temperature conditions. After the sulfurization is completed, the temperature is lowered, the start-up oil is introduced to wet the catalyst bed, and then the temperature is raised and the raw oil is replaced. The method adopts gas preheating, the gas temperature-carrying efficiency is low, the reactor heating rate is slow, and the sulfurization time is long. Summary of the invention

[0009] In view of the shortcomings of the prior art, the present invention provides a method for sulfurizing a fixed-bed residue oil hydrogenation catalyst. The sulfurization method of the present invention can shorten the catalyst sulfurization time, reduce the amount of sulfurizing agent, reduce equipment corrosion, and prevent the catalyst from being over-activated and coked in the initial stage, which may cause an increase in catalyst bed pressure drop and deterioration in hydrogenation product properties.

[0010] The invention provides a method for sulfurizing a fixed-bed residual oil hydrogenation catalyst. The method comprises: after completing catalyst loading, air tightness inspection and catalyst presulfurization preparation steps for a fixed-bed residual oil hydrogenation device, starting a catalyst reverse sulfurization process: firstly establishing a reverse full-circulation process of start-up diesel, then performing full-circulation presulfurization of diesel, when the reactor temperature is 230-260 DEG C, switching the start-up diesel to wax oil, then performing full-circulation presulfurization of wax oil, and finally using fresh sulfur-containing wax oil for non-full-circulation presulfurization.

[0011] In the above start-up method, the system pressure is maintained at 13-20 MPa during the entire process of the sulfidation method, and the system pressure refers to the outlet pressure at the top of the cold high-pressure separator.

[0012] In the above start-up method, the reverse sulfidation process of the catalyst means that the flow direction of the logistics through the catalyst during the sulfidation process is opposite to the flow direction of the liquid raw material logistics through the catalyst during normal production.

[0013] In the above start-up method, during the reverse sulfidation process of the catalyst, each feed (including diesel, wax oil, hydrogen and sulfiding agent) enters the reactor from the bottom of the last reactor and flows in reverse until it is discharged from the top of the first reactor.

[0014] In the above-mentioned start-up method, the establishment of a reverse full-cycle process of the start-up diesel includes the start-up diesel entering the reactor from the bottom of the last reactor, flowing in reverse until it is discharged from the top of the first reactor, the logistics discharged from the top of the first reactor entering the hot high-pressure separator (i.e., hot high-fraction), and obtaining hot high-fraction liquid and hot high-fraction gas after separation, the obtained hot high-fraction liquid entering the hot low-pressure separator (i.e., hot low-fraction) to separate the obtained hot low-fraction liquid as circulating oil, the obtained hot high-fraction gas entering the cold high-pressure separator (i.e., cold high-fraction) to separate the obtained cold high-fraction gas as circulating hydrogen, and the circulating oil and circulating hydrogen continue to be used as feed for the last reactor. In the process of establishing the reverse full-cycle of the start-up diesel, the reactor temperature is controlled not to exceed 230°C, preferably not to exceed the decomposition temperature of the sulfiding agent.

[0015] In the above-mentioned start-up method, the diesel full-cycle pre-sulfurization is after the diesel reverse full cycle is established. Under the condition of diesel reverse full cycle, a sulfiding agent is added to the feed, and after hydrogen sulfide penetrates the catalyst bed, the first constant temperature sulfurization is carried out.

[0016] In the above start-up method, before hydrogen sulfide penetrates the catalyst bed, the temperature is controlled at 210-230°C. Preferably, the reactor is heated at a rate of 5-20°C / h. The condition for hydrogen sulfide to penetrate the catalyst bed is that hydrogen sulfide is detected for the first time in the circulating hydrogen and the concentration is 0.1 vol.% to 0.5 vol.%, preferably 0.1 vol.% to 0.2 vol.%.

[0017] In the above start-up method, the first constant temperature sulfidation is carried out at 220-230°C for 4-8 hours. After hydrogen sulfide penetrates the catalyst bed to the first constant temperature sulfidation stage, the hydrogen sulfide content in the circulating hydrogen is controlled to be not less than 0.2 vol.%, preferably 0.2 vol.% to 1.0 vol.%.

[0018] In the above-mentioned start-up method, after the first constant temperature vulcanization, when the reactor temperature is 230-260°C, the start-up diesel is switched to wax oil, and then the wax oil full-cycle pre-vulcanization, i.e., the second constant temperature vulcanization, is performed. The second constant temperature vulcanization is performed at 280-290°C for 4-8 hours, and the hydrogen sulfide content in the circulating hydrogen is controlled to be not less than 0.5 vol.%, preferably 0.5 vol.%-1.0 vol.%. Preferably, the reactor is heated from the first constant temperature to the second constant temperature at a rate of 5-15°C / h.

[0019] In the above startup method, during the full-circulation presulfurization process, before the reactor temperature reaches 260° C., the method for controlling the concentration of hydrogen sulfide in the circulating hydrogen can be adjusted according to the injection amount of the sulfiding agent. After the reactor temperature reaches 260° C., the method for controlling the concentration of hydrogen sulfide in the circulating hydrogen can be adjusted according to the injection amount of the sulfiding agent and / or the circulating oil feed load.

[0020] In the above-mentioned start-up method, after the first constant temperature vulcanization, when the reactor temperature rises to 260-280°C, water is injected into the system. The water injection position is before the inlet of the heat exchanger at the top of the hot high-pressure separator and before the inlet of the high-pressure air cooling. In order to prevent the ammonium salt from crystallizing and blocking the pipeline, water can be injected into the pipeline to dissolve the ammonium salt. Hydrogen sulfide and ammonia will generate ammonium hydrogen sulfide crystals when the temperature is lower than 120°C, and hydrogen chloride and ammonia will generate ammonium chloride crystals when the temperature is lower than 200°C.

[0021] In the above-mentioned start-up method, the non-full-circulation presulfurization of fresh sulfur-containing wax oil is carried out after the full-circulation presulfurization of wax oil, and the fresh sulfur-containing wax oil is used as the feed of the last reactor without adding a sulfiding agent (i.e., no additional sulfiding agent is added), and the circulating oil is at most partially circulated (i.e., not circulated or partially circulated) during the sulfidation process. That is, in the non-circulation presulfurization process, without adding a sulfiding agent, fresh sulfur-containing wax oil or fresh sulfur-containing wax oil and part of the circulating oil enter the reactor from the bottom of the last reactor, flow in reverse until discharged from the top of the first reactor, and the logistics discharged from the top of the first reactor enters the hot high-pressure separator (i.e., hot high-fraction), and is separated to obtain hot high-fraction liquid and hot high-fraction gas, and the obtained hot high-fraction liquid enters the hot low-pressure separator (i.e., hot low-pressure separator) to separate the obtained hot low-fraction liquid as circulating oil (this circulating oil is at most partially circulated), and the obtained hot high-fraction gas enters the cold high-pressure separator (i.e., cold high-fraction) to separate the obtained cold high-fraction gas as circulating hydrogen, and the circulating hydrogen and the circulating oil used for circulation continue to be the feed of the last reactor.

[0022] In the above-mentioned start-up method, the non-full-circulation pre-sulfurization of the fresh sulfur-containing wax oil is to increase the temperature to 310-330°C and perform constant temperature sulfidation for 2-8 hours. During the non-full-circulation pre-sulfurization stage of the fresh sulfur-containing wax oil, the hydrogen sulfide content in the circulating hydrogen is controlled to be not less than 0.7 vol.%, preferably 0.7-1.0 vol.%. Preferably, the heating rate to the non-full-circulation pre-sulfurization constant temperature is 5-15°C / h.

[0023] In the above-mentioned start-up method, during the non-full circulation presulfurization process of the fresh sulfur-containing wax oil, the method for controlling the concentration of hydrogen sulfide in the circulating hydrogen can be adjusted according to the wax oil feed load, the sulfur content of the wax oil, the amount of circulating oil used for circulation, and the hydrogen sulfide content in the circulating hydrogen used for circulation. Among them, the method for adjusting the hydrogen sulfide content in the circulating hydrogen used for circulation is to start the circulating hydrogen desulfurization system to dehydrogenate the gas separated by the cold high-pressure separator before using it as circulating hydrogen. The circulating hydrogen desulfurization system can be a circulating hydrogen desulfurization tower that removes hydrogen sulfide from the circulating hydrogen through lean amine liquid.

[0024] In the above start-up method, preferably, during the vulcanization process, the feed amount of diesel or wax oil is controlled to be above 60wt.% of the designed processing load. Preferably, the feed amount of diesel or wax oil is 60wt.% to 90wt.% of the designed processing load.

[0025] In the above start-up method, the sulfiding agent is preferably at least one of carbon disulfide and dimethyl disulfide. Preferably, the preferred injection temperature of carbon disulfide is 180-190°C, and the preferred injection temperature of dimethyl disulfide is 190-200°C.

[0026] In the above-mentioned start-up method, during the non-full-circulation presulfurization process of fresh sulfur-containing wax oil, the sulfur-containing wax oil is preferably straight-run wax oil, and its sulfur content ranges from 1.5wt.% to 3.5wt.%, preferably 2.0wt.% to 3.5wt.%.

[0027] In the above-mentioned start-up method, before the non-full circulation presulfurization of the fresh sulfur-containing wax oil, the wax oil used is preferably straight-run wax oil. There is no particular restriction on the sulfur content in the wax oil used.

[0028] In the above start-up method, preferably, the initial hourly injection rate of the sulfiding agent is 3 wt.% to 6 wt.% of the theoretical sulfur required for complete sulfidation of all catalysts.

[0029] In the above start-up method, quenching hydrogen can be used to cool the reactor. Part of the circulating hydrogen can be used as quenching hydrogen to cool the reactor that needs to be cooled, and part of it can be used as circulating hydrogen to feed the reactor again.

[0030] In the above start-up method, after the sulfurization is completed, the reverse operation process is switched to the normal forward operation process, that is, the residual oil feedstock and hydrogen are fed from the first reactor and discharged from the last reactor.

[0031] In the above-mentioned start-up method, the catalyst loading, air tightness inspection, and catalyst presulfurization preparation steps of the fixed bed residual oil hydrogenation unit can be carried out by conventional methods in the art, and there is no special restriction in the present invention. The fixed bed residual oil hydrogenation unit is based on the conventional fixed bed residual oil hydrogenation unit in the art, and two pipelines are added between the first reactor and the last reactor, which are respectively used for the last reactor feeding and the first reactor discharging in the reverse sulfidation process to enter the subsequent separation process to realize the reverse sulfidation operation of the present invention. The catalyst presulfurization preparation step includes conventional steps such as wetting the catalyst and throwing out the dirty oil, the purpose is to wet the catalyst and remove the powder brought in by the catalyst. Among them, the start-up oil used for wetting the catalyst can be selected from at least one of straight-run diesel and / or straight-run wax oil, preferably wax oil. In the catalyst presulfurization preparation step, the reactor temperature is no more than 230°C, preferably no more than the decomposition temperature of the sulfiding agent. In the catalyst presulfurization preparation step, the feed amount of the start-up oil is more than 60wt.% of the design load, preferably 60wt.%~90wt.%.

[0032] In the above-mentioned start-up method, the fixed-bed residue oil hydrogenation unit adopts at least one hydrogenation reactor, more preferably multiple hydrogenation reactors are arranged in series, and more preferably three to five hydrogenation reactors are arranged.

[0033] In the above-mentioned start-up method, the catalyst generally includes a residue oil hydroprotection catalyst, a residue oil hydrodemetallization catalyst, a residue oil hydrodesulfurization catalyst, and may also include a residue oil hydrodenitrogenation and a carbon residue removal catalyst. Wherein, based on the total loading volume of the fixed-bed residue oil hydroprocessing catalyst, the residue oil hydroprotection catalyst accounts for 3% to 10% of the total loading volume, the residue oil hydrodemetallization catalyst accounts for 30% to 60% of the total loading volume, and the sum of the loading volumes of the residue oil hydrodesulfurization catalyst and the residue oil hydrodenitrogenation and carbon residue removal catalyst accounts for 37% to 67% of the total loading volume. The loading order of the catalyst can be loaded in a conventional grading order, and the loading order is generally that during normal production, the raw oil is sequentially contacted with the residue oil hydroprotection catalyst, the residue oil hydrodemetallization catalyst, the residue oil hydrodesulfurization catalyst, and the residue oil hydrodenitrogenation and carbon residue conversion catalyst. The residue oil hydroprocessing protection catalyst, residue oil hydrodemetallization catalyst, residue oil hydrodesulfurization catalyst, residue oil hydrodenitrogenation and residual carbon conversion catalyst can adopt the catalysts with corresponding functions commonly used in the art, such as CEN, FZC, ZTN and ZTS series residue oil hydroprocessing catalysts produced by the Catalyst Branch of Sinopec.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. The inventor has found through research that in a fixed bed residue oil hydrogenation unit, the catalyst loaded in the tail reactor has high activity and the head reactor has low activity. The catalyst loaded in the tail reactor requires more hydrogen sulfide than the head reactor during vulcanization. In order to ensure that the catalyst in the rear reactor is completely vulcanized, the existing method requires the injection of an excessive amount of vulcanizing agent. The inventor has further found that when the reverse vulcanization method of the present invention is adopted, the vulcanizing agent first enters the tail reactor to undergo a vulcanization reaction with a high-activity catalyst that requires more hydrogen sulfide, and then undergoes a vulcanization reaction with a low-activity catalyst that requires less hydrogen sulfide, without the need for excessive injection of a vulcanizing agent; and after the wax oil is switched, the wax oil introduced in reverse is easy to remove the organic sulfur in the start-up wax oil at a lower temperature under the action of the high-activity catalyst loaded in the tail reactor to generate hydrogen sulfide, and participate in the vulcanization reaction of the catalyst, so that the organic sulfur contained in the wax oil can be fully utilized to reduce the injection amount of the vulcanizing agent, so the vulcanization method of the present invention can save the amount of the vulcanizing agent to a great extent.

[0036] 2. The vulcanization method of the present invention is simple to operate, shortens the switching time of the vulcanization medium, and adopts a mode in which the wax oil replaces the diesel oil while the reactor is heated.

[0037] 3. The existing method requires the injection of excessive sulfiding agent to generate excessive hydrogen sulfide. A large amount of hydrogen sulfide in the circulating hydrogen does not participate in the reaction, which will cause corrosion to high-pressure air cooling and other equipment. The sulfidation method of the present invention utilizes the catalyst and reaction characteristics to ensure that the catalyst is completely sulfided without excessive hydrogen sulfide. The concentration of hydrogen sulfide in the circulating hydrogen is low. When it reaches the high-pressure air cooling and other equipment, the concentration of hydrogen sulfide is already low; and the circulating hydrogen desulfurization system can be reasonably started in advance, which effectively reduces the content of hydrogen sulfide in the circulating hydrogen again; therefore, the present invention can effectively reduce the corrosion of equipment and reduce the risk of equipment corrosion.

[0038] 4. In the sulfurization method of the present invention, the material flow flows in the reverse direction from the bottom to the top of the reactor, which increases the porosity between the catalyst beds and prevents carbon deposition and coking between the catalyst particles during the sulfurization process.

[0039] 5. The vulcanization method of the present invention has a fast heating rate and a low heating furnace load. When the temperature is increased during vulcanization, the source of heat for heating is mainly provided by the heat source device. In addition, the heat released by the vulcanization reaction can also appropriately increase the temperature. Since the rear reactor has high catalytic activity and releases more heat than the head reactor, and the more heat released by the tail reactor in the prior art cannot be utilized, the vulcanization method of the present invention drives the logistics to release more heat from the tail reactor to flow to the head reactor, which is beneficial to the rapid increase of the overall reactor temperature; because the reverse heating rate is fast, the reactor inlet temperature is appropriately lowered, and the target temperature can also be reached within the specified time. There is no need to heat the reactor feed to a higher temperature through a heating furnace, so the heating furnace load can be reduced. The higher the reactor temperature, the more obvious this advantage is; reverse vulcanization can make full use of the reaction heat released during the vulcanization process, reduce heat exchange steps, and avoid frequent heat exchange processes that lead to heat loss.

[0040] 6. The vulcanization method of the present invention can significantly shorten the vulcanization time.

[0041] 7. The sulfidation method of the present invention performs reverse sulfidation on the catalyst without the need for excessive hydrogen sulfide, and will not cause the situation in the prior art where the low-activity catalyst in the first reactor is overactivated, thereby avoiding the problem of catalyst coking that occurs in the early stage of the residual oil reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a schematic diagram of the process flow of the present invention.

[0043] Attached Figure 1 The markings are as follows:

[0044] 1 Fresh raw materials; 2, 4, 6, 16, 18, 23 three-way valve; 5 Forward logistics at the outlet of the heating furnace; 7 Logistics line at the top of the first reactor; 8 Fixed bed first reactor; 9 Logistics line at the top of the second reactor; 10 Fixed bed second reactor; 11 Logistics line at the top of the third reactor; 12 Fixed bed third reactor; 13 Logistics line at the top of the fourth reactor; 14 Fixed bed fourth reactor; 15, 17 Logistics lines at the bottom of the fourth reactor; 19 High heat fraction; 20 High heat fraction liquid; 21 Low heat fraction; 2 2 hot low fraction liquid; 24 circulation line; 25 circulation feed pump; 26 heating furnace outlet reverse logistics line; 27 reverse tower top logistics line; 28 hot high fraction gas; 29 air cooling; 30 cold high fraction; 31 cold high fraction gas; 33 circulating hydrogen compressor; 34 quenching hydrogen; 35 circulating hydrogen; 36 new hydrogen; 37 new hydrogen compressor; 38 mixed hydrogen; 39 cold high fraction liquid; 40 hot low fraction gas; 41 hydrogenation slag line; 42 sulfiding agent. 43 circulating hydrogen desulfurization tower; 44 lean amine liquid; 45 rich amine liquid. DETAILED DESCRIPTION

[0045] The start-up method provided by the present invention and its functions and effects are further described below in conjunction with the accompanying drawings and embodiments, but the present invention is not limited thereby. Many devices are omitted in the drawings, such as pumps, heat exchangers, heating furnaces, air cooling and stripping towers, but they are well known to those skilled in the art.

[0046] In the present invention, circulating hydrogen refers to the cold high-fraction gas separated by a cold high-pressure separator (i.e., cold high-fraction) as circulating hydrogen, and the concentration of hydrogen sulfide in the circulating hydrogen refers to the concentration of hydrogen sulfide in the cold high-fraction gas.

[0047] In the present invention, the reactor temperature is a weighted temperature calculated based on the weight of the catalyst loading volume of each reactor.

[0048] The start-up vulcanization process (reverse vulcanization process) of the present invention is as follows: Figure 1As shown, it includes four reactors, namely, the first reactor 8, the second reactor 10, the third reactor 12 and the fourth reactor 14, and the process includes: after the sulfiding medium is heated by the heating furnace 3, the three-way valve 4 controls the reverse logistics line 26 of the heating furnace outlet, and then the three-way valve 16 controls the logistics to enter the fixed bed fourth reactor 14 from the bottom logistics line 15 of the fourth reactor 14, and then the four-reaction tower top logistics line 13 enters from the bottom of the fixed bed third reactor 12, the three-reaction tower top logistics line 11 enters from the bottom of the fixed bed second reactor 10, the second reactor tower top logistics line 9 enters from the bottom of the fixed bed first reactor 8, and the logistics enters from the first reactor tower top After flowing out of logistics line 7, it is controlled by three-way valve 6 to go to reverse tower top logistics line 27, enters hot high fraction 19 through three-way valve 18, hot high fraction liquid 20 enters hot low fraction 21, hot low fraction liquid 22 goes to circulation line 24 through three-way valve 23, is mixed with sulfiding agent 42, and then is mixed with mixed hydrogen 38 through circulating feed pump and returned to the heating furnace inlet, hot high fraction gas 28 enters cold high fraction 30 after passing through heat exchange equipment such as air cooling 31, cold high fraction gas 31 is pressurized and divided into quenching hydrogen 34 and circulating hydrogen 35, new hydrogen 36 is pressurized by new hydrogen compressor 37 and mixed with circulating hydrogen to form mixed hydrogen 38. When the circulating hydrogen desulfurization system is activated, the circulating hydrogen enters from the bottom of the circulating hydrogen desulfurization tower 43 after being separated by the cold high-pressure separator, and the lean amine liquid 44 enters from the top of the desulfurization tower. After the two phases are in countercurrent contact, the desulfurized circulating hydrogen flows out from the top of the desulfurization tower and enters the circulating hydrogen compressor. The lean amine liquid absorbs hydrogen sulfide to generate rich amine liquid 45, which flows out from the bottom of the desulfurization tower for regeneration.

[0049] The existing conventional vulcanization process is operated according to the normal production process, such as Figure 1 As shown, four reactors are included, namely, first reactor 8, second reactor 10, third reactor 12 and fourth reactor 14. The process includes: after the sulfiding medium is heated by the heating furnace 3, it is controlled by the three-way valve 4 to go to the forward logistics line 5 at the outlet of the heating furnace, and then the logistics are controlled by the three-way valve 6 to enter the fixed bed first reactor 8 from the top logistics 7 of the first reactor tower, the top logistics 9 of the second reactor tower enters the fixed bed second reactor 10, the top logistics 11 of the third reactor tower enters the fixed bed third reactor 12, the top logistics 13 of the fourth reactor tower enters the fixed bed fourth reactor 14, and the bottom logistics 15 of the fourth reactor tower enters the fixed bed fourth reactor 16. The hot high fraction gas 28 is controlled by three-way valves 16 and 18 to enter the hot high fraction 19, the hot high fraction liquid 20 enters the hot low fraction 21, the hot low fraction liquid 22 goes to the circulation line 24 through the three-way valve 23, is mixed with the sulfiding agent 44, and then is mixed with the mixed hydrogen 38 through the circulation feed pump and returned to the heating furnace inlet, the hot high fraction gas 28 enters the cold high fraction 30 after passing through the air cooling 29 and other heat exchange equipment, the cold high fraction gas 31 is pressurized and divided into quenching hydrogen 34 and circulating hydrogen 35, the new hydrogen 36 is pressurized by the new hydrogen compressor 37 and mixed with the circulating hydrogen to form mixed hydrogen 38.

[0050] The embodiments and comparative examples of the present invention adopt Figure 1The fixed-bed residue oil hydrogenation unit includes four reactors, namely, the first reactor, the second reactor, the third reactor and the fourth reactor, wherein the catalysts are hydrogenation protection catalysts (FZC-103D, FZC-103E), hydrodemetallization catalysts (FZC-28A, FZC-204A), hydrodesulfurization catalysts (FZC-33BT), and hydrodenitrogenation catalysts (FZC-41BT). The first reactor is loaded with the same volume of FZC-103D and FZC-103E catalysts, the second reactor is loaded with the same volume of FZC-28A and FZC-204A catalysts, the third reactor is loaded with FZC-33BT catalyst, and the fourth reactor is loaded with FZC-41BT catalyst. The loading volume ratio of the first reactor: the second reactor: the third reactor: the fourth reactor is 12:43:21:24, and the total catalyst loading amount is 507 tons. The catalyst grading and the vulcanizing agent used in the embodiments and comparative examples of the present invention are the same; the start-up diesel used in the embodiments and comparative examples is straight-run diesel, and the start-up wax oil used in Example 2 is high-sulfur straight-run wax oil. The other embodiments and comparative examples use low-sulfur straight-run wax oil, and its properties are shown in Table 1. The vulcanizing agent uses dimethyl disulfide. The main conditions of the catalyst vulcanization process of the embodiments and comparative examples of the present invention are compared in Table 2, the properties of the raw oil are shown in Table 3, the main evaluation conditions are shown in Table 4, and the evaluation results of the embodiments and comparative examples are shown in Table 5.

[0051] In the examples and comparative examples of the present invention, hydrogen sulfide penetration of the catalyst bed means that the concentration of hydrogen sulfide in the circulating hydrogen is detected to be higher than 0.1 vol. % after the injection of the sulfiding agent.

[0052] Table 1 Properties of the start-up oil used in each case

[0053] project Straight run diesel Low sulfur straight run wax oil High sulfur straight run wax oil S, wt.% 0.8 1.7 3.3 N, μg / g 24 418 722 Distillation range, ℃ ASTM D-86 ASTM D-1160 ASTM D-1160 Initial distillation point 213 348 366 Final distillation point 356 520 542

[0054] Example 1

[0055] This embodiment adopts the sulfurization method of the present invention. After the fixed bed residue oil hydrogenation unit is completed with catalyst loading and air tightness inspection, hydrogen is introduced, the pressure of the reaction system is controlled to be 18 MPa, the temperature is gradually increased, and the start-up diesel is positively introduced from the first reactor into the reaction system to wet the catalyst, and the waste oil is thrown out to clean the catalyst. When the throwing is completed, the reactor temperature is controlled to reach 170°C.

[0056] Start the catalyst reverse sulfidation process:

[0057] First, establish a diesel reverse full cycle process, introduce diesel and hydrogen from the bottom of the last reactor, and make them flow in reverse until they are discharged from the top of the first reactor, and establish a diesel reverse full cycle process. In the process of establishing the diesel reverse full cycle, control the reactor temperature not to exceed 170℃;

[0058] Then, the full-cycle pre-sulfurization process is carried out. When the reactor temperature is 170°C, the sulfiding agent is injected at a flow rate of 1.5t / h, and the diesel feed rate is controlled at 85wt.% of the design load, which is 160t / h. At the same time, the temperature at the outlet of the heating furnace is increased to 220°C at 15°C / h. After the sulfiding agent is smoothly injected into the reaction system, the injection rate of the sulfiding agent is increased to 3.5t / h and maintained until hydrogen sulfide penetrates. When the reaction temperature rises to 220°C, the temperature is stopped and hydrogen sulfide penetration is waited. After hydrogen sulfide penetrates, the concentration of hydrogen sulfide in the circulating hydrogen is controlled to be 0.2-1.0vol.%, and the first constant temperature sulfurization is carried out for 4 hours. Subsequently, the temperature of the reactor was raised to 290°C at a rate of 10°C / h. When the temperature reached 250°C, fresh wax oil was injected to replace the diesel in the device. After the wax oil was switched, the wax oil was fully circulated. During the heating process, the amount of sulfiding agent injected was gradually reduced until the injection of sulfiding agent was stopped while ensuring that the hydrogen sulfide content in the circulating hydrogen was 0.5-1.0 vol.%. When the reactor temperature reached 260°C, water was injected. When the reactor temperature reached 290°C, a second constant temperature sulfidation was performed for 4 hours, during which the hydrogen sulfide content in the circulating hydrogen was controlled to be 0.5-1.0 vol.%.

[0059] Then, the wax oil is subjected to a non-full-circulation pre-sulfurization process. After the second constant-temperature sulfurization is completed, lean amine liquid is added, the circulating hydrogen desulfurization tower is opened, and the full-circulation process is changed to a fully open circuit (i.e., the circulating oil is not circulated). Fresh wax oil is injected at 85wt.% of the design load, i.e., 160t / h. At the same time, the reactor temperature is increased to 320°C at a rate of 10°C / h. After reaching 320°C, the temperature is kept constant for 2 hours before the sulfurization is completed. During this period, the hydrogen sulfide content in the circulating hydrogen is controlled to be 0.7-1.0vol.%.

[0060] Example 2

[0061] This embodiment adopts the sulfurization method of the present invention. After the catalyst is loaded and the airtightness is checked on the fixed bed residue oil hydrogenation unit, hydrogen is introduced, the pressure of the reaction system is controlled to be 19 MPa, the temperature is gradually increased, and the start-up diesel is positively introduced from the first reactor into the reaction system to wet the catalyst, and the waste oil is thrown out to clean the catalyst. When the throwing is completed, the reactor temperature is controlled to reach 185°C.

[0062] Start the catalyst reverse sulfidation process:

[0063] First, establish a diesel reverse full cycle process, introduce diesel and hydrogen from the bottom of the last reactor, and make them flow in reverse until they are discharged from the top of the first reactor, and establish a diesel reverse full cycle process. In the process of establishing the diesel reverse full cycle, control the reactor temperature not to exceed 185℃;

[0064] Then, the full-cycle pre-sulfurization process is carried out. When the reactor temperature is 185°C, the sulfiding agent is injected at a flow rate of 2.0 t / h, and the diesel feed rate is controlled at 80 wt.% of the design load, which is 150 t / h. At the same time, the temperature at the outlet of the heating furnace is raised to 230°C at 15°C / h. After the sulfiding agent is smoothly injected into the reaction system, the injection rate of the sulfiding agent is increased to 3.0 t / h and maintained until hydrogen sulfide penetrates. When the reaction temperature rises to 230°C, the temperature is stopped and hydrogen sulfide penetration is waited. After hydrogen sulfide penetrates, the concentration of hydrogen sulfide in the circulating hydrogen is controlled to be 0.2-1.0 vol.%, and the first constant temperature sulfidation is carried out for 4 hours. Subsequently, the temperature of the reactor was raised to 290°C at a rate of 6°C / h. When the temperature reached 260°C, fresh wax oil was injected to replace the diesel in the device. After the wax oil was switched, the wax oil was fully circulated. During the heating process, the amount of sulfiding agent injected was gradually reduced until the injection of sulfiding agent was stopped while ensuring that the hydrogen sulfide content in the circulating hydrogen was 0.5-1.0 vol.%. When the temperature of the reactor reached 260°C, water was injected. When the temperature of the reactor reached 290°C, a second constant temperature sulfidation was performed for 3 hours, during which the hydrogen sulfide content in the circulating hydrogen was controlled to be 0.5-1.0 vol.%.

[0065] Then the wax oil is subjected to a non-full-circulation pre-sulfurization process. After the second constant-temperature sulfurization is completed, lean amine liquid is added, and the circulating hydrogen desulfurization tower is opened. The full-circulation process is changed to a partial circulation process. The total feed rate at the reactor inlet is adjusted to 160 t / h, i.e. 85 wt.% of the design load, of which the mass ratio of fresh wax oil and circulating oil is 1:1. At the same time, the reactor temperature is increased to 320°C at a rate of 15°C / h, and the sulfurization is terminated after the temperature is kept constant for 4 hours after reaching 320°C. During this period, the hydrogen sulfide content in the circulating hydrogen is controlled to be 0.7-1.0 vol.%.

[0066] Example 3

[0067] This embodiment adopts the sulfurization method of the present invention. After the catalyst is loaded and the airtightness is checked on the fixed bed residue oil hydrogenation device, hydrogen is introduced, the pressure of the reaction system is controlled to be 20 MPa, the temperature is gradually increased, and the start-up diesel is positively introduced from the first reactor to the reaction system to wet the catalyst, and the waste oil is thrown out to clean the catalyst. When the throwing is completed, the reactor temperature is controlled to reach 170°C.

[0068] Start the catalyst reverse sulfidation process:

[0069] First, establish a diesel reverse full cycle process, introduce diesel and hydrogen from the bottom of the last reactor, and make them flow in reverse until they are discharged from the top of the first reactor, and establish a diesel reverse full cycle process. In the process of establishing the diesel reverse full cycle, control the reactor temperature not to exceed 200℃;

[0070] Then, the full-cycle pre-sulfurization process is carried out. When the reactor temperature is 200°C, the sulfiding agent is injected at a flow rate of 2.0 t / h, and the diesel feed rate is controlled at 85wt.% of the design load, which is 160 t / h. At the same time, the temperature at the outlet of the heating furnace is increased to 230°C at 10°C / h. After the sulfiding agent is smoothly injected into the reaction system, the injection rate of the sulfiding agent is increased to 3.5 t / h and maintained until hydrogen sulfide penetrates. When the reaction temperature rises to 230°C, the temperature is stopped and hydrogen sulfide penetration is waited. After hydrogen sulfide penetrates, the hydrogen sulfide concentration in the circulating hydrogen is controlled to be 0.2-1.0 vol.%, and the first constant temperature sulfurization is carried out for 4 hours. Subsequently, the temperature of the reactor was raised to 280°C at a rate of 10°C / h. When the temperature reached 240°C, fresh wax oil was injected to replace the diesel in the device. After the wax oil was switched, the wax oil was fully circulated. During the heating process, the amount of sulfiding agent injected was gradually reduced until the injection of sulfiding agent was stopped while ensuring that the hydrogen sulfide content in the circulating hydrogen was 0.5-1.0 vol.%. When the reactor temperature reached 260°C, water was injected. When the reactor temperature reached 280°C, a second constant temperature sulfidation was performed for 4 hours, during which the hydrogen sulfide content in the circulating hydrogen was controlled to be 0.5-1.0 vol.%.

[0071] Then, the wax oil is subjected to a non-full-circulation pre-sulfurization process. After the second constant-temperature sulfurization is completed, lean amine liquid is added, the circulating hydrogen desulfurization tower is opened, and the full-circulation process is changed to a fully open circuit (i.e., the circulating oil is not circulated). Fresh wax oil is injected at 85wt.% of the design load, i.e., 160t / h. At the same time, the reactor temperature is increased to 310°C at a rate of 15°C / h. After reaching 310°C, the temperature is kept constant for 6 hours before the sulfurization is completed. During this period, the hydrogen sulfide content in the circulating hydrogen is controlled to be 0.7-1.0vol.%.

[0072] Comparative Example 1

[0073] This comparative example adopts a conventional sulfurization method (operated according to the process flow during normal production). After the fixed-bed residual oil hydrogenation unit is completed with catalyst loading and airtightness inspection, hydrogen is introduced, the pressure of the reaction system is controlled to be 18 MPa, and the temperature begins to be gradually increased. Start-up diesel is positively introduced into the reaction system from the first reactor to wet the catalyst, and the dirty oil is thrown out to clean the catalyst. After the throwing out is completed, the full circulation of the start-up oil is established, and the reactor temperature is controlled to reach 180°C.

[0074] Start the catalyst sulfidation process:

[0075] Start injecting sulfiding agent at a flow rate of 1.5t / h, and at the same time, heat the outlet of the heating furnace at a rate of 5℃ / h to 230℃. After ensuring that the sulfiding agent is smoothly injected into the reaction system, increase the injection amount of the sulfiding agent to 3.0t / h, and maintain the injection amount until hydrogen sulfide penetrates. When the reaction temperature rises to 230℃, stop heating and wait for hydrogen sulfide to penetrate. After hydrogen sulfide penetrates and the concentration of hydrogen sulfide in the circulating hydrogen is 0.2-1.0vol.%, the first constant temperature sulfidation is carried out for 6 hours. Then the reactor temperature is raised to 280℃ at a rate of 5℃ / h. When it rises to 250℃, it is changed to full open circuit to inject fresh wax oil to replace the diesel in the device. After the wax oil is switched, it is changed to full circulation. During this period, the sulfiding agent is injected continuously. When the reactor temperature rises to 280℃, the second constant temperature is carried out for 6 hours, during which the hydrogen sulfide content in the circulating hydrogen is controlled to be 1.0-1.5vol.%;

[0076] Then the reactor temperature was raised to 310°C at a rate of 5°C / h, and the temperature was kept constant for 8 hours before the sulfidation was completed. During this period, the hydrogen sulfide content in the circulating hydrogen was controlled to be 1.5-2.0 vol.% by adjusting the injection amount of the sulfiding agent.

[0077] Comparative Example 2

[0078] This comparative example adopts a conventional sulfurization method (operated according to the process during normal production). After the fixed-bed residue oil hydrogenation unit is filled with the catalyst and the airtightness is checked, hydrogen is introduced, the pressure of the reaction system is controlled to be 17MPa, and the temperature is gradually increased. The start-up wax oil is positively introduced into the reaction system from the first reactor to wet the catalyst, and the dirty oil is thrown out to clean the catalyst. After the throwing out is completed, a full circulation process of wax oil is established, and the reactor temperature is controlled to reach 190°C.

[0079] Start the catalyst sulfidation process:

[0080] Start injecting sulfiding agent at a flow rate of 2.0t / h, and at the same time, increase the temperature of the heating furnace outlet to 230℃ at 10℃ / h. After ensuring that the sulfiding agent is smoothly injected into the reaction system, increase the injection amount of the sulfiding agent to 3.5t / h, and maintain the injection amount until hydrogen sulfide penetrates. When the reaction temperature rises to 230℃, stop heating and wait for hydrogen sulfide to penetrate. After hydrogen sulfide penetrates and the concentration of hydrogen sulfide in the circulating hydrogen is 0.2-1.0vol.%, the first constant temperature sulfidation is performed for 8 hours. Then the reactor temperature is increased to 290℃ at 6℃ / h. When the reactor temperature rises to 290℃, the second constant temperature sulfidation is performed for 8 hours, during which the hydrogen sulfide content in the circulating hydrogen is controlled to be 1.0-1.5vol.%;

[0081] Subsequently, the reactor temperature was raised to 320°C at a rate of 10°C / h, and the temperature was kept constant for 6 hours before the sulfidation was completed. During this period, the hydrogen sulfide content in the circulating hydrogen was controlled to be 1.5-2.0 vol.% by adjusting the injection amount of the sulfiding agent.

[0082] Table 2 Comparison of main conditions of catalyst sulfidation process in various cases

[0083]

[0084]

[0085] *Note: Reactor temperature

[0086] As can be seen from Table 2, firstly, by adopting the sulfurization method of the present invention, the time used for catalyst sulfurization is significantly shorter than that of the comparative example, and the overall average start-up time is saved by nearly 20 hours, which is helpful to improve the efficiency of the refinery; secondly, by adopting the sulfurization method of the present invention, the amount of sulfurizing agent used is saved by more than 30wt.%; thirdly, by adopting the sulfurization method of the present invention, the content of hydrogen sulfide in the circulating hydrogen during the catalyst sulfurization process is significantly lower than that of the comparative example, thereby reducing the corrosion of hydrogen sulfide to the equipment.

[0087] In addition, sampling and analysis were performed after the device was running stably. Under the premise that the main operating conditions including feed amount, reaction temperature, reaction pressure and hydrogen-to-oil ratio were consistent, the overall reactor pressure drop of the embodiment device was lower than that of the comparative example. It is worth noting that the pressure drop of the front reactor of the embodiment was significantly lower than that of the comparative example, which is conducive to the long-term operation of the device. The properties of the hydrogenated product are shown in Table 5. The various indicators of the hydrogenated residue oil in the embodiment are better than those of the comparative example.

[0088] Table 3 Raw oil properties

[0089]

[0090] Table 4 Main operating conditions

[0091]

[0092]

[0093] Table 5 Properties of the hydrogenation products obtained in each case

[0094] project index Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Carbon residue, wt.% ≯3.10 2.65 2.68 2.71 2.95 2.93 S, wt.% ≯0.20 0.13 0.14 0.15 0.22 0.19 N, μg / g ≯2500 1000 1091 1122 1320 1209 Ni+V, μg / g ≯12.00 8.42 8.63 8.66 9.54 9.17

[0095] It can be seen from Tables 3 to 5 that the device using the above catalyst sulfurization method can meet the technical index requirements during actual operation, and the impurity content of hydrogenated residue oil and the pressure drop of the reactor in the embodiment are significantly lower than those in the comparative example. The sulfurization method of the present invention is better than the traditional method in terms of catalyst sulfurization effect, and there is still room for optimization within the proposed operating conditions. In addition, it has the unique advantages of simple operation, short time consumption and small amount of sulfurizing agent.

Claims

1. A method for sulfurizing a fixed-bed residue oil hydrogenation catalyst, comprising: After completing the catalyst loading, air tightness inspection, and catalyst presulfurization preparation steps for the fixed bed residue oil hydrotreating unit, the catalyst reverse sulfidation process is started: first, a reverse full-cycle process of the start-up diesel is established, and then the diesel is fully presulfided. When the reactor temperature is 230-260°C, the start-up diesel is switched to wax oil, and then the wax oil is fully presulfided. Finally, fresh sulfur-containing wax oil is used for non-full-cycle presulfidation. Establishing a reverse full-cycle process of start-up diesel includes: the start-up diesel enters the reactor from the bottom of the last reactor, flows in reverse until it is discharged from the top of the first reactor, the logistics discharged from the top of the first reactor enters a hot high-pressure separator, namely a hot high-fraction separator, and is separated to obtain hot high-fraction liquid and hot high-fraction gas, the obtained hot high-fraction liquid enters a hot low-pressure separator, namely a hot low-fraction separator, and the obtained hot low-fraction liquid is used as circulating oil, the obtained hot high-fraction gas enters a cold high-pressure separator, namely a cold high-fraction separator, and the obtained cold high-fraction gas is used as circulating hydrogen, and the circulating oil and circulating hydrogen are continued as feeds for the last reactor, wherein, in the process of establishing a reverse full-cycle process of start-up diesel, the reactor temperature is controlled not to exceed 230°C; The diesel full-cycle pre-sulfurization is to add a sulfiding agent to the feed after the reverse full-cycle of the diesel is established, and to carry out the first constant-temperature sulfidation after the hydrogen sulfide penetrates the catalyst bed; the first constant-temperature sulfidation is carried out at a constant temperature of 220-230°C for 4-8 hours, and the hydrogen sulfide content in the circulating hydrogen is controlled to be not less than 0.2 vol.% from the time the hydrogen sulfide penetrates the catalyst bed to the first constant-temperature sulfidation stage; After the first constant temperature vulcanization, when the reactor temperature is 230-260°C, the start-up diesel is switched to wax oil, and then the wax oil full-cycle pre-vulcanization, i.e., the second constant temperature vulcanization, is carried out at 280-290°C for 4-8 hours. During the process of rising from the first constant temperature to the second constant temperature and during the second constant temperature vulcanization stage, the hydrogen sulfide content in the circulating hydrogen is controlled to be not less than 0.5 vol.%; The non-full-circulation presulfurization of fresh sulfur-containing wax oil is carried out after the full-circulation presulfurization of wax oil. Without adding a sulfiding agent, fresh sulfur-containing wax oil is used as the feed of the last reactor, and the circulating oil is at most partially circulated in the sulfidation process.

2. The vulcanization method according to claim 1, characterized in that: The hydrogenation catalyst comprises a residual oil hydrogenation protection catalyst, a residual oil hydrogenation demetallization catalyst and a residual oil hydrogenation desulfurization catalyst; the catalyst loading sequence is that during normal production, the feedstock oil is sequentially contacted with the residual oil hydrogenation protection catalyst, the residual oil hydrogenation demetallization catalyst and the residual oil hydrogenation desulfurization catalyst.

3. The vulcanization method according to claim 1, characterized in that: The system pressure is maintained at 13-20 MPa during the entire process of the vulcanization method.

4. The vulcanization method according to claim 1, characterized in that: In the process of establishing the reverse full circulation of the start-up diesel, the reactor temperature is controlled not to exceed the decomposition temperature of the sulfiding agent.

5. The vulcanization method according to claim 1, characterized in that: After hydrogen sulfide penetrates the catalyst bed to the first constant temperature sulfidation stage, the hydrogen sulfide content in the circulating hydrogen is controlled to be 0.2 vol.%~1.0 vol.%.

6. The vulcanization method according to claim 5, characterized in that During the process of rising from the first constant temperature to the second constant temperature and in the second constant temperature sulfidation stage, the hydrogen sulfide content in the circulating hydrogen is controlled to be 0.5 vol.%~1.0 vol.%.

7. The vulcanization method according to claim 5 or 6, characterized in that: The reactor is heated from the first constant temperature to the second constant temperature at a rate of 5-15°C / h.

8. The vulcanization method according to claim 5, characterized in that: Before hydrogen sulfide penetrates the catalyst bed, the temperature is controlled at 210~230℃.

9. The vulcanization method according to claim 8, characterized in that The reactor is heated at a rate of 5-20°C / h.

10. The vulcanization method according to claim 5, characterized in that: The condition for hydrogen sulfide to penetrate the catalyst bed is that hydrogen sulfide is detected for the first time in the circulating hydrogen and the concentration is 0.1 vol.%~0.5 vol.%.

11. The vulcanization method according to claim 10, characterized in that The concentration of hydrogen sulfide is 0.1vol.%~0.2vol.%.

12. The vulcanization method according to claim 1 or 11, characterized in that: The non-full-circulation pre-sulfurization of the fresh sulfur-containing wax oil is to increase the temperature to 310-330° C. and perform constant temperature sulfurization for 2-8 hours. During the non-full-circulation pre-sulfurization stage, the hydrogen sulfide content in the circulating hydrogen is controlled to be not less than 0.7 vol.%.

13. The vulcanization method according to claim 12, characterized in that In the non-full-circulation presulfurization stage, the hydrogen sulfide content in the circulating hydrogen is controlled to be 0.7~1.0vol.%.

14. The vulcanization method according to claim 12, characterized in that The heating rate to the non-full-cycle pre-sulfurization constant temperature is 5~15℃ / h.

15. The vulcanization method according to claim 1, characterized in that: During the vulcanization process, the feed amount of diesel or wax oil is controlled to be above 60wt.% of the designed processing load.

16. The vulcanization method according to claim 15, characterized in that The feed amount of diesel or wax oil is 60wt.%~90wt% of the designed processing load.

17. The vulcanization method according to claim 5 or 6, characterized in that: The vulcanizing agent is at least one of carbon disulfide and dimethyl disulfide; the injection temperature of carbon disulfide is 180-190°C, and the injection temperature of dimethyl disulfide is 190-200°C.

18. The vulcanization method according to claim 11, characterized in that: In the non-full-circulation presulfurization process of fresh sulfur-containing wax oil, the sulfur-containing wax oil is straight-run wax oil, and its sulfur content ranges from 1.5 wt.% to 3.5 wt.%.

19. The vulcanization method according to claim 18, characterized in that The sulfur content ranges from 2.0 wt.% to 3.5 wt.%.

20. The vulcanization method according to claim 1, characterized in that: Before the non-full-circulation presulfurization of fresh sulfur-containing wax oil, the wax oil used is straight-run wax oil.

21. The vulcanization method according to claim 1, characterized in that: The fixed bed residue oil hydrogenation unit adopts at least one hydrogenation reactor.

22. The vulcanization method according to claim 21, characterized in that The fixed bed residue oil hydrogenation device is provided with a plurality of hydrogenation reactors in series.

23. The vulcanization method according to claim 22, characterized in that The fixed-bed residue oil hydrogenation device is provided with three to five hydrogenation reactors.

24. The vulcanization method according to claim 1, characterized in that The hydrogenation catalyst also includes a residue oil hydrodenitrogenation and carbon removal catalyst; the catalyst loading sequence is that during normal production, the feedstock oil is sequentially contacted with the residue oil hydroprotection catalyst, the residue oil hydrodemetallization catalyst, the residue oil hydrodesulfurization catalyst and the residue oil hydrodenitrogenation and carbon removal catalyst.

25. The vulcanization method according to claim 1, 21 or 24, characterized in that Based on the total loading volume of the fixed-bed residue hydroprocessing catalyst, the residue hydroprotection catalyst accounts for 3% to 10% of the total loading volume, the residue hydrodemetallization catalyst accounts for 30% to 60% of the total loading volume, and the sum of the loading volumes of the residue hydrodesulfurization catalyst and the residue hydrodenitrogenation and carbon removal catalyst accounts for 37% to 67% of the total loading volume.

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