阅读说明：本技术 一种加氢处理方法和系统 (Hydrotreating method and system ) 是由 邵志才 邓中活 戴立顺 聂红 刘涛 施瑢 聂鑫鹏 任亮 杨清河 胡大为 孙淑玲 于 2018-07-06 设计创作，主要内容包括：本发明涉及一种加氢处理方法和系统,该方法包括：(1)、将加氢原料和氢气依次经过加氢保护反应区、加氢脱金属区和深度加氢反应区中进行加氢保护反应、加氢脱金属反应和深度加氢反应；其中,所述加氢保护反应区至少包括在上游的第一加氢保护反应器和在下游的第二加氢保护反应器；(2)、当第一加氢保护反应器中的加氢保护催化剂需要更换时,将第一加氢保护反应器切出并更换为加氢脱金属催化剂或深度加氢催化剂,并将所述加氢原料和氢气引入第二加氢保护反应器中进行加氢保护反应,所得反应流出物引入更换催化剂的第一加氢保护反应器、所述加氢脱金属区和深度加氢反应区中。本发明的方法和系统可以延长装置的运转周期。(The invention relates to a hydrotreating process and system, the process comprising: (1) sequentially passing the hydrogenation raw material and hydrogen through a hydrogenation protection reaction zone, a hydrogenation demetalization zone and a deep hydrogenation reaction zone to carry out hydrogenation protection reaction, hydrogenation demetalization reaction and deep hydrogenation reaction; wherein the hydroprocessing reaction zone comprises at least a first hydroprocessing reactor upstream and a second hydroprocessing reactor downstream; (2) and when the hydrogenation protection catalyst in the first hydrogenation protection reactor needs to be replaced, cutting out the first hydrogenation protection reactor and replacing the first hydrogenation protection reactor with a hydrogenation demetalization catalyst or a deep hydrogenation catalyst, introducing the hydrogenation raw material and hydrogen into a second hydrogenation protection reactor for hydrogenation protection reaction, and introducing the obtained reaction effluent into the first hydrogenation protection reactor with the catalyst replaced, the hydrogenation demetalization area and the deep hydrogenation reaction area. The method and system of the present invention can extend the operating cycle of the device.)

1. A hydroprocessing process, comprising:

(1) sequentially passing the hydrogenation raw material and hydrogen through a hydrogenation protection reaction zone, a hydrogenation demetalization zone and a deep hydrogenation reaction zone to contact with a hydrogenation protection catalyst, a hydrogenation demetalization catalyst and a deep hydrogenation catalyst, and performing a hydrogenation protection reaction, a hydrogenation demetalization reaction and a deep hydrogenation reaction; the hydrogenation protection reaction zone at least comprises an upstream first hydrogenation protection reactor and a downstream second hydrogenation protection reactor according to the flow direction of a reaction material, the hydrodemetallization zone at least comprises one hydrodemetallization reactor, and the deep hydrogenation reaction zone at least comprises one deep hydrogenation reactor;

(2) and when the hydrogenation protection catalyst in the first hydrogenation protection reactor needs to be replaced, cutting out the first hydrogenation protection reactor and replacing the first hydrogenation protection reactor with a hydrogenation demetalization catalyst or a deep hydrogenation catalyst, introducing the hydrogenation raw material and hydrogen into a second hydrogenation protection reactor for hydrogenation protection reaction, and introducing the obtained reaction effluent into the first hydrogenation protection reactor with the catalyst replaced, the hydrogenation demetalization area and the deep hydrogenation reaction area.

2. The method according to claim 1, wherein in step (2), if the hydrogenation protection catalyst in the first hydrogenation protection reactor is replaced by the hydrogenation demetallization catalyst, the reaction effluent obtained from the second hydrogenation protection reactor is introduced into the first hydrogenation protection reactor with the replaced catalyst, and then sequentially introduced into the hydrogenation demetallization zone and the deep hydrogenation reaction zone;

if the hydrogenation protection catalyst in the first hydrogenation protection reactor is replaced by a deep hydrogenation catalyst, the reaction effluent obtained by the second hydrogenation protection reactor is firstly sequentially introduced into the hydrogenation demetalization area and the first hydrogenation protection reactor with the replaced catalyst, and then introduced into the deep hydrogenation reaction area; or if the hydrogenation protection catalyst in the first hydrogenation protection reactor is replaced by the deep hydrogenation catalyst, the reaction effluent obtained by the second hydrogenation protection reactor is firstly sequentially introduced into the hydrogenation demetalization area and the deep hydrogenation reaction area, and then introduced into the first hydrogenation protection reactor with the replaced catalyst.

3. The process of claim 1, wherein the hydrogenation protection catalyst in the hydrogenation protection reaction zone comprises a first carrier and a first active metal component loaded on the first carrier, wherein the first active metal component is selected from a group VIB metal and/or a group VIII metal, and the content of the first active metal component in terms of oxide is 0-12 wt% based on the dry weight of the hydrogenation protection catalyst;

the hydrodemetallization catalyst in the hydrodemetallization region comprises a second carrier and a second active metal component loaded on the second carrier, wherein the second active metal component is selected from VIB group metals and/or VIII group metals, and the content of the second active metal component in terms of oxide is 0-30 wt% on the basis of the dry weight of the hydrodemetallization catalyst;

the deep hydrogenation catalyst in the deep hydrogenation reaction zone comprises a third carrier and a third active metal component loaded on the third carrier, wherein the third active metal component is selected from VIB group metals and/or VIII group metals, and the content of the third active metal component is 5-35 wt% calculated by oxides on the basis of the dry weight of the deep hydrogenation catalyst.

4. The method of claim 1, wherein in step (2), the first hydrogenation protection reactor is determined to require replacement when one of the following conditions occurs:

a. the temperature in the first hydrogenation protection reactor reaches a limit value;

b. the pressure drop of the first hydrogenation protection reactor reaches a limit value;

c. an uncontrolled hot spot was detected in the first hydroprocessing reactor.

5. The process of claim 1, wherein the first, second, hydrodemetallization, and deep hydrogenation reactors are each independently selected from at least one of an upflow reactor, a downflow reactor, and a countercurrent reactor.

6. The method according to claim 1, wherein the hydrogenation feedstock is at least one selected from the group consisting of a residual oil, a mixed oil of a residual oil and a straight-run distillate, coal tar, ethylene tar, coker gas oil, deep-draw gas oil, coker gas oil, catalytically cracked gas oil, recycle oil, slurry oil, thermally cracked gas oil, coal tar gas oil, catalytically cracked gas oil, coker gas oil, coal tar gas oil, and thermally cracked naphtha.

7. The process of claim 1, wherein the hydrogenation feedstock has an iron and calcium content of 15-50 μ g/g, a nickel content of 15-75 μ g/g, and a vanadium content of 15-75 μ g/g.

8. The process of claim 1, wherein the conditions for the hydrogenation protection reaction, the hydrodemetallization reaction, and the deep hydrogenation reaction each independently comprise: the hydrogen partial pressure is 5.0-22.0MPa, the reaction temperature is 330-^-1The volume ratio of hydrogen to the hydrogenation feed was 350-2000.

9. A hydrotreating system comprises a hydrogenation protection reaction zone (1), a hydrogenation demetalization zone (2) and a deep hydrogenation reaction zone (3) which are sequentially communicated according to the flow direction of reaction materials, wherein the hydrogenation protection reaction zone (1) at least comprises a first hydrogenation protection reactor (11) at the upstream and a second hydrogenation protection reactor (12) at the downstream, the hydrogenation demetalization zone (2) at least comprises one hydrogenation demetalization reactor, and the deep hydrogenation reaction zone (3) at least comprises one deep hydrogenation reactor;

the first hydro-protective reactor (11) is arranged to be switched out of the system for catalyst replacement and into the system as a hydrodemetallization reactor or a deep hydrogenation reactor downstream of the second hydro-protective reactor (12).

10. The system according to claim 9, comprising a first line (31), a second line (32), a third line (33), a fourth line (34), a fifth line (35) and a sixth line (36), the first line (31) being used to feed hydrogenation feedstock and hydrogen and communicating with the feed inlets of the first (11) and second (12) hydrogenation protection reactors through the second (32) and third (33) lines, respectively, the discharge outlet of the first hydrogenation protection reactor (11) communicating with the feed inlet of the second hydrogenation protection reactor (12) through the fourth line (34), the discharge outlet of the second hydrogenation protection reactor (12) communicating with the feed inlet of the hydrodemetallization zone (2) through the fifth line (35), the discharge outlet of the hydrodemetallization zone (2) communicating with the feed inlet of the deep hydrogenation zone (3) through the sixth line (36), a first valve (41), a second valve (42) and a third valve (43) are respectively arranged on the second pipeline (32), the third pipeline (33) and the fourth pipeline (34);

the system also comprises a seventh pipeline (37) and an eighth pipeline (38), the discharge hole of the second hydrogenation protection reactor (12) is communicated with the feed hole of the first hydrogenation protection reactor (11) through the seventh pipeline (37), the discharge hole of the first hydrogenation protection reactor (11) is communicated with the feed hole of the hydrodemetallization region (2) through the eighth pipeline (38), and a fourth valve (44), a fifth valve (45) and a sixth valve (46) are respectively arranged on the fifth pipeline (35), the seventh pipeline (37) and the eighth pipeline (38); or the system also comprises a ninth pipeline (39) and a tenth pipeline (310), the discharge hole of the hydrodemetallization zone (2) is communicated with the feed hole of the first hydrogenation protection reactor (11) through the ninth pipeline (39), the discharge hole of the first hydrogenation protection reactor (11) is communicated with the feed hole of the deep hydrogenation reaction zone (3) through the tenth pipeline (310), and the sixth pipeline (36), the ninth pipeline (39) and the tenth pipeline (310) are respectively provided with a seventh valve (47), an eighth valve (48) and a ninth valve (49); or the system further comprises an eleventh pipeline (311), a twelfth pipeline (312) and a thirteenth pipeline (313), the discharge hole of the deep hydrogenation reaction zone (3) is communicated with the feed hole of the first hydrogenation protection reactor (11) through the eleventh pipeline (311), the discharge hole of the first hydrogenation protection reactor (11) is communicated with the twelfth pipeline (312), the discharge hole of the deep hydrogenation reaction zone (3) is communicated with the thirteenth pipeline (313), and the eleventh pipeline (311), the twelfth pipeline (312) and the thirteenth pipeline (313) are respectively provided with a tenth valve (410), an eleventh valve (411) and a twelfth valve (412).

11. The system of claim 9, wherein the first, second, hydrodemetallization, and deep hydrogenation reactors are each independently selected from at least one of an upflow reactor, a downflow reactor, and a countercurrent reactor.

Technical Field

The invention relates to the technical field of hydrogenation, in particular to a hydrotreating method and a hydrotreating system.

Background

Along with the increasing weight change of crude oil, the variety of crude oil is increasing, and the requirement on the weight change of heavy oil products is also increasing. "heavy oil" refers to hydrocarbons of high asphaltene content derived from topped crude oil, petroleum residuum, oil sands, bitumen, shale oil, liquefied coal, or reclaimed oil. The hydrogenation process of heavy oil is a heavy oil deep processing technology, and is characterized by that in the presence of hydrogen gas and catalyst the heavy oils of residual oil, etc. are undergone the processes of hydrodesulfurization, hydrodenitrogenation, hydrodemetallization, residual carbon conversion and hydrocracking reaction, so that the obtained hydrogenated residual oil can be used as feed material for high-quality catalytic cracking to produce light oil product so as to attain the goal of maximally lightening residual oil and implement non-residual oil refinery.

To date, four process types have been developed for residuum hydrogenation: fixed beds, ebullated beds, slurry beds, and moving beds. Among the four process types, the fixed bed process is mature and easy to operate, and the equipment investment is relatively low; the product hydrogen content is increased more and the unconverted residue can be used as RFCC feed, which is the most industrially applicable of the four processes.

For the fixed bed residue hydrogenation process, metal impurities (such as vanadium, nickel, calcium, iron and the like), unsaturated components and dirt in the residue raw material are easily deposited on the surface of the catalyst and in gaps among catalyst particles, so that catalyst orifices are blocked, catalyst deactivation is caused, and bed pressure drop is rapidly increased, so that the device is frequently shut down and the catalyst is replaced. For residual oil with high Ni and V metal contents, metal in the residual oil hydrogenation reaction process can be deposited in catalyst micropores, and for residual oil with high Ni and V metal contents, if the operation time is short, the catalyst micropores can be blocked due to excessive metal deposition, so that the catalyst is inactivated, and the operation period of a residual oil hydrogenation device is seriously influenced. Therefore, the key point for processing the poor-quality residual oil is to solve the problems of the rapid rise of the pressure drop and the catalyst deactivation caused by metal deposition.

Disclosure of Invention

The object of the present invention is to provide a hydroprocessing method and system that can extend the run length of the plant.

In order to achieve the above object, the present invention provides a hydrotreating method including:

(1) sequentially passing the hydrogenation raw material and hydrogen through a hydrogenation protection reaction zone, a hydrogenation demetalization zone and a deep hydrogenation reaction zone to contact with a hydrogenation protection catalyst, a hydrogenation demetalization catalyst and a deep hydrogenation catalyst, and performing a hydrogenation protection reaction, a hydrogenation demetalization reaction and a deep hydrogenation reaction; the hydrogenation protection reaction zone at least comprises an upstream first hydrogenation protection reactor and a downstream second hydrogenation protection reactor according to the flow direction of a reaction material, the hydrodemetallization zone at least comprises one hydrodemetallization reactor, and the deep hydrogenation reaction zone at least comprises one deep hydrogenation reactor;

(2) and when the hydrogenation protection catalyst in the first hydrogenation protection reactor needs to be replaced, cutting out the first hydrogenation protection reactor and replacing the first hydrogenation protection reactor with a hydrogenation demetalization catalyst or a deep hydrogenation catalyst, introducing the hydrogenation raw material and hydrogen into a second hydrogenation protection reactor for hydrogenation protection reaction, and introducing the obtained reaction effluent into the first hydrogenation protection reactor with the catalyst replaced, the hydrogenation demetalization area and the deep hydrogenation reaction area.

Optionally, if the hydrogenation protection catalyst in the first hydrogenation protection reactor is replaced by a hydrodemetallization catalyst, introducing a reaction effluent obtained from the second hydrogenation protection reactor into the first hydrogenation protection reactor with the replaced catalyst, and then sequentially introducing the reaction effluent into the hydrodemetallization region and the deep hydrogenation reaction region;

if the hydrogenation protection catalyst in the first hydrogenation protection reactor is replaced by a deep hydrogenation catalyst, the reaction effluent obtained by the second hydrogenation protection reactor is firstly sequentially introduced into the hydrogenation demetalization area and the first hydrogenation protection reactor with the replaced catalyst, and then introduced into the deep hydrogenation reaction area; or if the hydrogenation protection catalyst in the first hydrogenation protection reactor is replaced by the deep hydrogenation catalyst, the reaction effluent obtained by the second hydrogenation protection reactor is firstly sequentially introduced into the hydrogenation demetalization area and the deep hydrogenation reaction area, and then introduced into the first hydrogenation protection reactor with the replaced catalyst.

Optionally, the hydrogenation protection catalyst in the hydrogenation protection reaction zone comprises a first carrier and a first active metal component loaded on the first carrier, wherein the first active metal component is selected from a group VIB metal and/or a group VIII metal, and the content of the first active metal component in terms of oxide is 0 to 12 wt% based on the dry weight of the hydrogenation protection catalyst;

the hydrodemetallization catalyst in the hydrodemetallization region comprises a second carrier and a second active metal component loaded on the second carrier, wherein the second active metal component is selected from VIB group metals and/or VIII group metals, and the content of the second active metal component in terms of oxide is 0-30 wt% on the basis of the dry weight of the hydrodemetallization catalyst;

the deep hydrogenation catalyst in the deep hydrogenation reaction zone comprises a third carrier and a third active metal component loaded on the third carrier, wherein the third active metal component is selected from VIB group metals and/or VIII group metals, and the content of the third active metal component is 5-35 wt% calculated by oxides on the basis of the dry weight of the deep hydrogenation catalyst.

Optionally, in step (2), when one of the following conditions occurs in the first hydrogenation protection reactor, it is determined that the hydrogenation protection catalyst needs to be replaced:

a. the temperature in the first hydrogenation protection reactor reaches a limit value;

b. the pressure drop of the first hydrogenation protection reactor reaches a limit value;

c. an uncontrolled hot spot was detected in the first hydroprocessing reactor.

Optionally, the first hydrogenation protection reactor, the second hydrogenation protection reactor, the hydrodemetallization reactor and the deep hydrogenation reactor are each independently selected from at least one of an upflow reactor, a downflow reactor and a countercurrent reactor.

Optionally, the hydrogenation raw material is at least one selected from residual oil, mixed oil of residual oil and straight-run distillate oil, coal tar, ethylene tar, coker gas oil, deep-drawing gas oil, coker diesel oil, catalytically cracked diesel oil, recycle oil, slurry oil, thermal cracked diesel oil, coal tar diesel oil, catalytically cracked gasoline, coker gasoline, coal tar gasoline, and thermal cracked naphtha.

Optionally, the contents of iron and calcium in the hydrogenation raw material are both 15-50 μ g/g, the content of nickel is 15-75 μ g/g, and the content of vanadium is 15-75 μ g/g.

Optionally, the conditions of the hydrogenation protection reaction, the hydrodemetallization reaction and the deep hydrogenation reaction each independently include: the hydrogen partial pressure is 5.0-22.0MPa, the reaction temperature is 330-^-1The volume ratio of hydrogen to the hydrogenation feed was 350-2000.

The invention also provides a hydrotreating system, which comprises a hydrogenation protection reaction zone, a hydrogenation demetalization zone and a deep hydrogenation reaction zone which are sequentially communicated according to the flow direction of reaction materials, wherein the hydrogenation protection reaction zone at least comprises an upstream first hydrogenation protection reactor and a downstream second hydrogenation protection reactor, the hydrogenation demetalization zone at least comprises one hydrogenation demetalization reactor, and the deep hydrogenation reaction zone at least comprises one deep hydrogenation reactor;

the first hydroprocessing protection reactor is configured to be switched out of the system for catalyst replacement and into the system as a hydrodemetallization reactor or a deep hydroprocessing reactor downstream of the second hydroprocessing protection reactor.

Optionally, the system includes a first pipeline, a second pipeline, a third pipeline, a fourth pipeline, a fifth pipeline and a sixth pipeline, the first pipeline is used for feeding hydrogenation raw materials and hydrogen and is respectively communicated with the feed inlets of the first hydrogenation protection reactor and the second hydrogenation protection reactor through the second pipeline and the third pipeline, the discharge outlet of the first hydrogenation protection reactor is communicated with the feed inlet of the second hydrogenation protection reactor through the fourth pipeline, the discharge outlet of the second hydrogenation protection reactor is communicated with the feed inlet of the hydrogenation demetallization zone through the fifth pipeline, the discharge outlet of the hydrogenation demetallization zone is communicated with the feed inlet of the deep hydrogenation reaction zone through the sixth pipeline, and the second pipeline, the third pipeline and the fourth pipeline are respectively provided with a first valve, a second valve and a third valve;

the system also comprises a seventh pipeline and an eighth pipeline, wherein a discharge hole of the second hydrogenation protection reactor is communicated with a feed inlet of the first hydrogenation protection reactor through the seventh pipeline, a discharge hole of the first hydrogenation protection reactor is communicated with a feed inlet of the hydrogenation demetallization region through the eighth pipeline, and a fourth valve, a fifth valve and a sixth valve are respectively arranged on the fifth pipeline, the seventh pipeline and the eighth pipeline; or the system further comprises a ninth pipeline and a tenth pipeline, the discharge hole of the hydrodemetallization region is communicated with the feed inlet of the first hydrogenation protection reactor through the ninth pipeline, the discharge hole of the first hydrogenation protection reactor is communicated with the feed inlet of the deep hydrogenation reaction region through the tenth pipeline, and a seventh valve, an eighth valve and a ninth valve are respectively arranged on the sixth pipeline, the ninth pipeline and the tenth pipeline; or the system further comprises an eleventh pipeline, a twelfth pipeline and a thirteenth pipeline, the discharge hole of the deep hydrogenation reaction zone is communicated with the feed inlet of the first hydrogenation protection reactor through the eleventh pipeline, the discharge hole of the first hydrogenation protection reactor is communicated with the twelfth pipeline, the discharge hole of the deep hydrogenation reaction zone is communicated with the thirteenth pipeline, and the eleventh pipeline, the twelfth pipeline and the thirteenth pipeline are respectively provided with a tenth valve, an eleventh valve and a twelfth valve.

Optionally, the first hydrogenation protection reactor, the second hydrogenation protection reactor, the hydrodemetallization reactor and the deep hydrogenation reactor are each independently selected from at least one of an upflow reactor, a downflow reactor and a countercurrent reactor.

Compared with the prior art, the invention has the advantages that:

(1) after the first hydrogenation protection reactor is cut off, the first hydrogenation protection reactor is changed into a demetalization reactor or a deep hydrogenation reactor, so that the demetalization performance or the carbon residue hydrogenation conversion performance can be enhanced.

(2) Under the condition of prolonging the running period of the device, the invention avoids the repeated switching of the device and reduces the potential safety hazard.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of a first embodiment of the system of the present invention.

Fig. 2 is a schematic structural diagram of a second embodiment of the system of the present invention.

Fig. 3 is a schematic structural diagram of a third embodiment of the system of the present invention.

Description of the reference numerals

1 hydrogenation protection reaction zone 11 first hydrogenation protection reactor 12 second hydrogenation protection reactor

2 hydrogenation demetalization zone 3 deep hydrogenation reaction zone

31 first line 32 second line 33 third line

34 fourth line 35 fifth line 36 sixth line

37 seventh line 38 eighth line 39 ninth line

310 tenth pipeline 311 eleventh pipeline 312 twelfth pipeline

313 thirteenth line

41 first valve 42 second valve 43 third valve

44 fourth valve 45 fifth valve 46 sixth valve

47 seventh valve 48 eighth valve 49 ninth valve

410 tenth valve 411 eleventh valve 412 twelfth valve

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

The invention provides a hydrotreating process comprising:

(1) sequentially passing the hydrogenation raw material and hydrogen through a hydrogenation protection reaction zone, a hydrogenation demetalization zone and a deep hydrogenation reaction zone to contact with a hydrogenation protection catalyst, a hydrogenation demetalization catalyst and a deep hydrogenation catalyst, and performing a hydrogenation protection reaction, a hydrogenation demetalization reaction and a deep hydrogenation reaction; the hydrogenation protection reaction zone at least comprises an upstream first hydrogenation protection reactor and a downstream second hydrogenation protection reactor according to the flow direction of a reaction material, the hydrodemetallization zone at least comprises one hydrodemetallization reactor, and the deep hydrogenation reaction zone at least comprises one deep hydrogenation reactor;

(2) and when the hydrogenation protection catalyst in the first hydrogenation protection reactor needs to be replaced, cutting out the first hydrogenation protection reactor and replacing the first hydrogenation protection reactor with a hydrogenation demetalization catalyst or a deep hydrogenation catalyst, introducing the hydrogenation raw material and hydrogen into a second hydrogenation protection reactor for hydrogenation protection reaction, and introducing the obtained reaction effluent into the first hydrogenation protection reactor with the catalyst replaced, the hydrogenation demetalization area and the deep hydrogenation reaction area.

Compared with the prior art that the deactivated hydrogenation protection catalyst in the hydrogenation protection reactor is replaced by a new hydrogenation protection catalyst, the method provided by the invention has the advantages that the hydrogenation protection catalyst in the first hydrogenation protection catalyst is replaced by a hydrogenation demetalization catalyst or a deep hydrogenation catalyst with higher reaction activity, so that the product quality is improved on the premise of ensuring the operation period of a hydrogenation system.

In the present invention, the first hydrogenation protection reactor may be optionally used as a hydrodemetallization reactor or a deep hydrogenation reactor after the catalyst is replaced, and the cut-in position of the first hydrogenation protection reactor is not particularly limited in the present invention. Preferably, the present invention is divided into the following two embodiments according to the difference of catalyst replacement in the first hydrogenation protection reactor in the step (2):

a. if the hydrogenation protection catalyst in the first hydrogenation protection reactor is replaced by the hydrogenation demetalization catalyst, the reaction effluent obtained by the second hydrogenation protection reactor is firstly introduced into the first hydrogenation protection reactor with the replaced catalyst, and then is sequentially introduced into the hydrogenation demetalization area and the deep hydrogenation reaction area. In this embodiment, the first hydroprocessing protection reactor is switched into the first hydrodemetallization reactor after the hydroprocessing system as the hydrodemetallization zone, thereby utilizing its replaced more active catalyst to improve the hydrodemetallization performance and to improve the life of the catalyst in the remaining hydrodemetallization reactors.

b. If the hydrogenation protection catalyst in the first hydrogenation protection reactor is replaced by a deep hydrogenation catalyst, the reaction effluent obtained by the second hydrogenation protection reactor is firstly sequentially introduced into the hydrogenation demetalization area and the first hydrogenation protection reactor with the replaced catalyst, and then introduced into the deep hydrogenation reaction area; or if the hydrogenation protection catalyst in the first hydrogenation protection reactor is replaced by the deep hydrogenation catalyst, the reaction effluent obtained by the second hydrogenation protection reactor is firstly sequentially introduced into the hydrogenation demetalization area and the deep hydrogenation reaction area, and then introduced into the first hydrogenation protection reactor with the replaced catalyst. In this embodiment, the first hydrogenation protection reactor is used as the first deep hydrogenation reactor or the last deep hydrogenation reactor of the deep hydrogenation reaction zone after being cut into the hydrotreating system, and the first deep hydrogenation reactor is used to help improve the deep hydrogenation performance by using the catalyst with higher activity to be replaced, and to improve the service life of the catalyst in the rest deep hydrogenation reactors, and the last deep hydrogenation reactor is used to help strengthen the deep hydrogenation performance and improve the quality of the reaction product. The deep hydrogenation reaction zone can comprise a transition demetalization desulfurization section, a hydrodesulfurization section, a hydrodecarbonization section or a hydrodenitrogenation section and other reaction sections which are sequentially connected in series, and each reaction section can be arranged in one reactor or one or more catalyst beds of one or more reactors.

In the invention, when the first hydrogenation protection reactor is cut out to replace the catalyst, the hydrogenation raw material and hydrogen can be firstly introduced into the second hydrogenation protection reactor, the hydrodemetallization region and the deep hydrogenation reaction region in sequence, and when the catalyst of the first hydrogenation protection reactor is replaced, the first hydrogenation protection reactor is cut back to the reaction system to be used as the hydrodemetallization reactor or the deep hydrogenation reactor.

In the present invention, the hydrogenation protection catalyst, the hydrodemetallization catalyst and the deep hydrogenation catalyst respectively filled in the hydrogenation protection reaction zone, the hydrodemetallization zone and the deep hydrogenation reaction zone are well known to those skilled in the art, for example, the hydrogenation protection catalyst in the hydrogenation protection reaction zone may include a first carrier and a first active metal component loaded on the first carrier, the first active metal component may be selected from a group VIB metal and/or a group VIII metal, and the content of the first active metal component in terms of oxide may be 0 to 12 wt% based on the dry weight of the hydrogenation protection catalyst; the hydrodemetallization catalyst in the hydrodemetallization zone can comprise a second carrier and a second active metal component loaded on the second carrier, wherein the second active metal component can be selected from group VIB metals and/or group VIII metals, and the content of the second active metal component in terms of oxides can be 0-30 wt% based on the dry weight of the hydrodemetallization catalyst; the deep hydrogenation catalyst in the deep hydrogenation reaction zone can comprise a third carrier and a third active metal component loaded on the third carrier, wherein the third active metal component can be selected from a VIB group metal and/or a VIII group metal, and the content of the third active metal component in terms of oxides can be 5-35 wt% based on the dry basis weight of the deep hydrogenation catalyst. The first, second and third supports may be conventional alumina, silica, or the like supports. In addition to the catalysts of the above composition, other catalysts may be made by themselves or commercially available to those skilled in the art, and the present invention will not be described in detail.

In step (2) of the present invention, when one of the following conditions occurs in the first hydrogenation protection reactor, it may be determined that the hydrogenation protection catalyst needs to be replaced: a. the temperature in the first hydrogenation protection reactor reaches the limit value, which indicates that the catalyst in the protection reactor has no activity, can not remove impurities such as iron, calcium and the like in the raw material, and can not protect the following catalyst, generally speaking, the temperature limit can be 420-430 ℃; b. the pressure drop of the first hydrogenation protection reactor reaches the limit value, the reactor is generally provided with the designed highest pressure drop limit, the internal components (such as an outlet collector) of the reactor can be damaged and the operation of a recycle hydrogen compressor can be influenced when the pressure drop is too high, and the existing pressure drop limit is generally designed to be about 0.7 MPa; c. the first hydrogenation protection reactor detects an uncontrollable hot spot, which can be also called a temperature runaway, and the uncontrollable hot spot can be obtained by measuring the radial temperature difference of the reactor, wherein the radial temperature difference is too large, which indicates that the distribution of reaction materials in a catalyst bed layer is not uniform, the service efficiency of the catalyst is influenced, the radial temperature difference does not exceed 25 ℃ in general, and the shutdown treatment is required if the radial temperature difference exceeds 30 ℃.

In the present invention, the hydrogenation protection reactor is well known to those skilled in the art, and may be, for example, a fixed bed reactor or an ebullated bed reactor, and the first hydrogenation protection reactor, the second hydrogenation protection reactor, the hydrodemetallization reactor and the deep hydrogenation reactor may each be independently selected from at least one of an upflow reactor, a downflow reactor and a counter-flow reactor. The downflow reactor refers to a reactor with a material flow flowing from top to bottom, the upflow reactor refers to a reactor with a material flow flowing from bottom to top, and the countercurrent reactor refers to a reactor with liquid and gas flowing in opposite directions. Other reactors may be used by those skilled in the art and the present invention will not be described in detail.

According to the present invention, the hydrogenation feedstock is well known to those skilled in the art, and for example, the hydrogenation feedstock may be at least one selected from the group consisting of a residual oil, a mixed oil of a residual oil and a straight-run distillate oil, coal tar, ethylene tar, coker wax oil, deep-draw wax oil, coker diesel oil, catalytically cracked diesel oil, recycle oil, slurry oil, thermally cracked diesel oil, coal tar diesel oil, catalytically cracked gasoline, coker gasoline, coal tar gasoline, and thermally cracked naphtha. The process of the present invention is particularly suitable for processing residua feedstocks that are susceptible to pressure drop, such as high calcium containing residua, and feedstocks that are susceptible to deactivation of residua hydrogenation catalysts, such as high metal containing residua, where the hydrogenation feedstocks may each have an iron and calcium content of 15-50 μ g/g, a nickel content of 15-75 μ g/g, and a vanadium content of 15-75 μ g/g.

In the present invention, the hydrogenation protection reaction is mainly to remove metal impurities such as iron, copper, calcium, etc., and foulants such as colloids and particulate matters, etc., in a hydrogenation feedstock (for example, residual oil) to protect a catalyst in a subsequent reactor, the hydrogenation demetallization reaction can be used to remove most of metal nickel and vanadium in the hydrogenation feedstock, the deep hydrogenation reaction is used to remove impurities such as metal, most of sulfur and nitrogen, etc., in the remaining portion of the hydrogenation feedstock, and the deep hydrogenation is used to achieve carbon residue hydroconversion, and the conditions of the hydrogenation protection reaction, the hydrogenation demetallization reaction, and the deep hydrogenation reaction can be residual oil hydrogenation process conditions, for example, each of the conditions can independently include: the hydrogen partial pressure is 5.0-22.0MPa, the reaction temperature is 330-^-1The volume ratio of hydrogen to the hydrogenation raw material (hydrogen-oil ratio for short) is 350-.

As shown in fig. 1-3, the present invention further provides a hydrotreating system, which comprises a hydrogenation protection reaction zone 1, a hydrodemetallization zone 2 and a deep hydrogenation reaction zone 3, which are sequentially communicated, wherein the hydrogenation protection reaction zone 1 at least comprises an upstream first hydrogenation protection reactor 11 and a downstream second hydrogenation protection reactor 12, the hydrodemetallization zone 2 at least comprises one hydrogenation demetalization reactor, and the deep hydrogenation reaction zone 3 at least comprises one deep hydrogenation reactor; the first hydro-protection reactor 11 is arranged to be switched out of the system for catalyst replacement and into the system as a hydrodemetallization reactor or a deep hydrogenation reactor downstream of the second hydro-protection reactor 12.

The first hydrogenation protection reactor of the system can be cut into a hydrogenation demetalization reactor or a deep hydrogenation reactor after the catalyst is replaced, so that the quality of the product is improved on the premise of ensuring the operation period of the hydrogenation system.

As shown in fig. 1 to 3, the system may include a first pipeline 31, a second pipeline 32, a third pipeline 33, a fourth pipeline 34, a fifth pipeline 35 and a sixth pipeline 36, the first pipeline 31 is used for feeding hydrogenation raw material and hydrogen and is respectively communicated with the feeding ports of the first hydrogenation protection reactor 11 and the second hydrogenation protection reactor 12 through the second pipeline 32 and the third pipeline 33, the discharging port of the first hydrogenation protection reactor 11 is communicated with the feeding port of the second hydrogenation protection reactor 12 through the fourth pipeline 34, the discharging port of the second hydrogenation protection reactor 12 is communicated with the feeding port of the hydrodemetallization zone 2 through the fifth pipeline 35, the discharging port of the hydrodemetallization zone 2 is communicated with the feeding port of the deep hydrogenation reaction zone 3 through the sixth pipeline 36, and the second pipeline 32, the third pipeline 33 and the fourth pipeline 34 are respectively provided with a first valve 41, a second valve 41 and a second valve 36, A second valve 42 and a third valve 43; the system of the present invention can be divided into the following two embodiments according to the catalyst replacement of the first hydrogenation protection reactor.

In the first embodiment, if the hydrogenation protection catalyst in the first hydrogenation protection reactor is replaced by a hydrodemetallization catalyst, as shown in fig. 1, the system may further include a seventh line 37 and an eighth line 38, the discharge port of the second hydrogenation protection reactor 12 is communicated with the feed port of the first hydrogenation protection reactor 11 through the seventh line 37, the discharge port of the first hydrogenation protection reactor 11 is communicated with the feed port of the hydrodemetallization region 2 through the eighth line 38, and the fifth line 35, the seventh line 37 and the eighth line 38 are respectively provided with a fourth valve 44, a fifth valve 45 and a sixth valve 46; in this embodiment, the first hydroprocessing protection reactor is switched into the first hydrodemetallization reactor after the hydroprocessing system as the hydrodemetallization zone, thereby utilizing its replaced more active catalyst to improve the hydrodemetallization performance and to improve the life of the catalyst in the remaining hydrodemetallization reactors.

In the second embodiment, if the hydrogenation protection catalyst in the first hydrogenation protection reactor is replaced by a deep hydrogenation catalyst, as shown in fig. 2, the system may further include a ninth pipeline 39 and a tenth pipeline 310, the discharge port of the hydrodemetallization zone 2 is communicated with the feed port of the first hydrogenation protection reactor 11 through the ninth pipeline 39, the discharge port of the first hydrogenation protection reactor 11 is communicated with the feed port of the deep hydrogenation reaction zone 3 through the tenth pipeline 310, and the sixth pipeline 36, the ninth pipeline 39 and the tenth pipeline 310 are respectively provided with a seventh valve 47, an eighth valve 48 and a ninth valve 49; or as shown in fig. 3, the system may further include an eleventh pipeline 311, a twelfth pipeline 312 and a thirteenth pipeline 313, the discharge port of the deep hydrogenation reaction zone 3 is communicated with the feed port of the first hydrogenation protection reactor 11 through the eleventh pipeline 311, the discharge port of the first hydrogenation protection reactor 11 is communicated with the twelfth pipeline 312, the discharge port of the deep hydrogenation reaction zone 3 is communicated with the thirteenth pipeline 313, and the eleventh pipeline 311, the twelfth pipeline 312 and the thirteenth pipeline 313 are respectively provided with a tenth valve 410, an eleventh valve 411 and a twelfth valve 412. In this embodiment, the first hydrogenation protection reactor is used as the first deep hydrogenation reactor or the last deep hydrogenation reactor of the deep hydrogenation reaction zone after being cut into the hydrotreating system, and as the first deep hydrogenation reactor, the deep hydrogenation performance is improved by using the catalyst with higher activity to be replaced, and the service life of the catalyst in the rest deep hydrogenation reactors is prolonged, and as the last deep hydrogenation reactor, the deep hydrogenation performance is enhanced, and the quality of the reaction product is improved. The deep hydrogenation reaction zone can comprise a transition demetalization desulfurization section, a hydrodesulfurization section, a hydrodecarbonization section or a hydrodenitrogenation section and other reaction sections which are sequentially connected in series, and each reaction section can be arranged in one reactor or one or more catalyst beds of one or more reactors.

In the present invention, the hydrogenation protection reactor is well known to those skilled in the art, and may be, for example, a fixed bed reactor or an ebullated bed reactor, and the first hydrogenation protection reactor, the second hydrogenation protection reactor, the hydrodemetallization reactor and the deep hydrogenation reactor may each be independently selected from at least one of an upflow reactor, a downflow reactor and a counter-flow reactor. The downflow reactor refers to a reactor with a material flow flowing from top to bottom, the upflow reactor refers to a reactor with a material flow flowing from bottom to top, and the countercurrent reactor refers to a reactor with liquid and gas flowing in opposite directions. Other reactors may be used by those skilled in the art and the present invention will not be described in detail.

The manner in which the system of the present invention operates is further described below in conjunction with the appended drawings, but the invention is not so limited.

When the hydrotreating system is just started, as shown in fig. 1, the first hydrogenation protection reactor 11 and the second hydrogenation protection reactor 12 of the hydrogenation protection reaction zone 1 are connected in series and are in a series state with the subsequent hydrodemetallization zone 2 and the deep hydrogenation reaction zone 3, at this time, the first valve 41, the third valve 43, and the fourth valve 44 are in an open state, and the remaining valves are in a closed state, the reaction material enters the first hydrogenation protection reactor 11 through the first pipeline 31, the second pipeline 32, and the valve 41, then enters the second hydrogenation protection reactor 12 through the fourth pipeline 34 and the third valve 43, and the reaction effluent enters the hydrodemetallization zone 2 and the deep hydrogenation reaction zone 3 through the fifth pipeline 35 and the fourth valve 44. When the hydrogenation protection catalyst in the first hydrogenation protection reactor 11 needs to be replaced, the first valve 41 and the third valve 43 are closed, and at this time, the first hydrogenation protection reactor 11 is cut out from the system for replacing the catalyst and is subjected to sulfidation and passivation, and the following two embodiments are provided according to the difference of the replacement of the catalyst in the first hydrogenation protection reactor 11:

in the first embodiment, when the hydrogenation protection catalyst in the first hydrogenation protection reactor is replaced with the hydrodemetallization catalyst, as shown in fig. 1, the second valve 42, the fifth valve 45 and the sixth valve 46 are opened, the fourth valve 44 is closed, so that the reaction material firstly enters the second hydrogenation protection reaction zone 12 through the first pipeline 31, the third pipeline 33 and the second valve 42, the obtained reaction effluent enters the first hydrogenation protection reactor 11 with the catalyst replaced through the seventh pipeline 37 and the fifth valve 45, the obtained reaction effluent enters the subsequent hydrogenation and demetalization zone 2 and the deep hydrogenation reaction zone 3 through the eighth pipeline 38 and the sixth valve 46, and the first hydrogenation protection reactor 11 at this time serves as the first hydrogenation and demetalization reactor of the hydrogenation and demetalization zone.

In the second embodiment, the first hydrogenation protection reactor is replaced with a deep hydrogenation catalyst, and the two types of hydrogenation protection catalyst are shown in fig. 2 and 3.

As shown in fig. 2, the second valve 42, the eighth valve 48, and the ninth valve 49 are opened, the seventh valve 47 is closed, at this time, the reaction material firstly enters the second hydrogenation protection reaction zone 12 through the first pipeline 31, the third pipeline 33, and the second valve 42, the obtained reaction effluent enters the hydrodemetallization zone 2 through the fifth pipeline 35, the obtained reaction effluent enters the first hydrogenation protection reactor 11 with the catalyst replaced through the ninth pipeline 39 and the eighth valve 48, and then enters the deep hydrogenation reaction zone 2 through the tenth pipeline 310 and the ninth valve 49, at this time, the first hydrogenation protection reactor 11 serves as a first deep hydrogenation reactor of the deep hydrogenation reaction zone.

As shown in fig. 3, the second valve 42, the tenth valve 410, the eleventh valve 411 are opened, the twelfth valve 412 is closed, at this time, the reaction material firstly enters the second hydrogenation protection reaction zone 12 through the first pipeline 31, the third pipeline 33 and the second valve 42, the obtained reaction effluent sequentially enters the hydrodemetallization zone 2 and the deep hydrogenation reaction zone 3 through the fifth pipeline 35 and the sixth pipeline 36, the reaction effluent obtained from the deep hydrogenation reaction zone 3 enters the first hydrogenation protection reactor 11 with the catalyst replaced through the eleventh pipeline 311 and the tenth valve 410, the obtained reaction effluent is sent out of the system through the twelfth pipeline 312 and the eleventh valve 411, and at this time, the first hydrogenation protection reactor 11 serves as the last deep hydrogenation reactor of the deep hydrogenation reaction zone.

The invention is further illustrated by the following examples, but is not to be construed as being limited thereto.