CN109988602A

CN109988602A - A kind of flexible wax oil hydrogenation treatment process

Info

Publication number: CN109988602A
Application number: CN201711469264.1A
Authority: CN
Inventors: 刘涛; 李宝忠; 张学辉; 彭绍忠; 崔哲; 乔凯
Original assignee: China Petroleum and Chemical Corp; Sinopec Dalian Research Institute of Petroleum and Petrochemicals
Current assignee: China Petroleum and Chemical Corp; Sinopec Dalian Research Institute of Petroleum and Petrochemicals
Priority date: 2017-12-29
Filing date: 2017-12-29
Publication date: 2019-07-09

Abstract

The invention discloses a kind of flexible wax oil hydrogenation treatment process.Wax oil raw material enters the first hydrotreating reactor after mixing with hydrogen, is divided into two strands by the material after the hydrotreating catalyst bed of top；One material is extracted out the first hydrotreating reactor among bed, and is mixed into the second hydrotreating reactor with LCO and is carried out hydrogenation reaction；Another strand of material continues to flow downwardly through the hydrotreating catalyst bed of lower part, and gained the first hydrotreating reaction material and the second hydrotreating reaction material carry out gas-liquid separation and fractionation, obtain naphtha, diesel oil and add hydrogen heavy distillat etc..The present invention provides one kind on a set of hydrogenation plant flexible processing different material oil, produce the flexible hydroprocessing technique of fine quality catalytic cracking raw material, heat entrained by the first hydrotreated material of part can be made full use of, realizes the coupling operation of the first hydrotreating reactor and the second hydrotreating reactor.

Description

A kind of flexible wax oil hydrogenation treatment process

Technical field

The invention belongs to petroleum refining fields, and in particular to one kind flexibly produces high-quality urge as feedstock oil using wax oil and LCO Change the flexible hydroprocessing technique of cracked stock.

Background technique

Fluid catalytic cracking (FCC) is one of the important means of light materialization of heavy oil, but with catalyzed cracking processing original The in poor quality and heaviness of material, operating condition is more and more harsher, and light-end products yield and product property are deteriorated, and catalytic cracking Raw material hydrotreating techniques not only can remove sulphur, nitrogen, metal impurities content, can also improve the cracking performance of charging, drop Low FCC operating severity improves product distribution, improves purpose product selectivity, reduces dry gas and coke yield, improves FCC dress The economy set reduces purpose product sulfur content, reduces SOx and NOx content etc. in regenerated flue gas.Catalytic cracking light cycle oil (LCO) there are the sulphur and nitrogen of certain content in, exist in the form of organic compound, and arene content is high, especially two rings The content of the above aromatic hydrocarbons is high, and usual LCO is recycled directly back to continue to convert in catalytic cracking unit, or enters hydrotreater Catalytic cracking unit is entered back into after adding hydrogen, either enters other devices and processes or directly as product.

CN103773495A, CN101875856A, CN102465035A and CN001896192A disclose a kind of wax oil and add The technology of refining LCO is mixed in hydrogen treatment process, main purpose is production fine quality catalytic cracking raw material, or allows LCO in wax oil The coupling technique recycled between hydrotreater and catalytic cracking unit realizes the clean manufacturing of catalytic cracking unit.But by The hydrogenation depth of the direct hydrogenation after wax oil is mixed with LCO, LCO not can be effectively controlled, can only (catalysis is split with mixed hydrogenation product Change raw material) sulfur content or nitrogen content as control target, be unfavorable for LCO produce premium effective control.

It is usually all that LCO directly mixes refining in conclusion comparing existing LCO hydrogen addition technology and wax oil hydrogenation processing technique Carried out into wax oil hydrotreating unit plus hydrogen, obtained after mixed hydrogenation plus hydrogen wax oil and plus hydrogen LCO split collectively as catalysis Disguise the raw material set, i.e. LCO returns again to catalytic cracking unit after adding hydrogen, and due to not controlling the hydrogenation depth of LCO deliberately, catalysis is split Change quality of gasoline and do not reach best, and without the Combined machining technology of reaction mass coupling.

Summary of the invention

In view of the deficiencies of the prior art, the present invention provides a kind of flexible wax oil hydrogenation treatment process, i.e., by from using Extraction section reaction stream in the middle part of one hydrotreating reactor adds the wax oil feedstock oil and LCO feedstock oil by two The group technology that hydrogen handles reaction zone produces fine quality catalytic cracking raw material.

A kind of flexible wax oil hydrogenation treatment process of the invention, includes the following steps:

A, wax oil feedstock oil passes through the first hydrotreating reactor top hydrotreating catalyst under hydroprocessing conditions first Bed obtains the first hydrotreating logistics, this part reaction stream is divided into two parts, and a portion extracts the first hydrotreating out Reactor；

B, the first hydrotreating logistics continuation of remainder is anti-by the first hydrotreating under hydroprocessing conditions in step a The lower part hydrotreating catalyst bed for answering device obtains the first hydrotreating reactor product stream by separation, fractionation (or vapour Mention) after obtain the first hydrogenation gas product, the first hydrotreated naphtha product, the first hydrogenated diesel oil and first plus hydrogen heavy distillat；

C, the first hydrotreating logistics of the first hydrotreating reactor of the resulting extraction of step a is adding at hydrogen after mixing with LCO The hydrotreating catalyst bed for passing through the second hydrotreating reactor under the conditions of reason obtains the generation of the second hydrotreating reactor Logistics obtains the second hydrogenation gas product, the second hydrotreated naphtha product, second plus hydrogen bavin after separation, fractionation (or stripping) Oil and second adds hydrogen heavy distillat.

Flexible wax oil hydrogenation treatment process according to the present invention, step b and separation in step c and fractional distillation process are preferably total With a set of separation, fractionating system.Wherein, high pressure hydrogen-rich gas obtained by separation process recycles after being recycled or mix respectively and makes With.

The requirement of product quality, environmental requirement, technological operation etc. all carries out the raw material oil nature of catalytic cracking unit Limitation, the especially limitation of sulfur content, and due to the difference of feedstock oil composition, the distribution of catalytic cracking product and property also have Biggish difference；Research shows that: the aromatic hydrogenation saturation depth of LCO is affected to fcc gasoline product quality, especially It is that mononuclear aromatics is antiknock component in gasoline, increases and the content of mononuclear aromatics in hydrogen LCO is added to can be increased catalytic cracking The octane number of gasoline, and the first hydrotreating logistics extracted out is reacted because having already been through partial hydrogenation, adds the reduction of hydrogen difficulty, because This its mixed with LCO after can achieve the purpose that hydrodesulfurization, hydrodenitrogeneration requirement under the operating condition relatively mitigated, and at this time Just can control the hydrogenation depth of LCO, i.e., under the premise of meeting sulfur content by LCO two cycloaromatics and polycyclic aromatic hydrocarbon add Hydrogen is to mononuclear aromatics, rather than hydrogenation depth excessively generates cycloalkane or hydrogenation depth is insufficient and generate two cycloaromatics, this The content of Aromatics in Fcc Naphtha can be improved in product after sample hydrotreating when being re-introduced into catalytic cracking unit, from And improve the octane number of catalytically cracked gasoline.

Compared with prior art, the advantages of present invention flexible wax oil hydrogenation treatment process, is:

It 1, include at least two hydrotreating catalyst beds in the first hydrotreating reactor in the present invention.Existed by setting The first processing material extraction step among first hydrotreating reactor bed, is not necessarily to special operation, can be realized to first Effective distribution of hydrotreated material stock, then make obtained material by hydrogenation combination technique, it is good so as to produce Purpose product.Meanwhile abstraction reaction logistics is technically also to be easily achieved among reactor bed.And in the prior art In, LCO is typically directly mixed into a hydrotreating reactor with wax oil feedstock oil and directly produces catalytically cracked material.

2, the present invention among the catalyst bed of the first hydrotreating reactor by being arranged the first hydrotreating logistics Withdrawing device, the first hydrotreating logistics by wax oil raw material Jing Guo the first hydrotreating extract reactor, and by itself and LCO Mixing is sent into the second hydrotreating reactor for being separately provided and carries out hydrogenation reaction, due in some wax oil raw material The impurity such as sulphur, nitrogen have been hydrogenated removing, therefore further add the difficulty of hydrogen to reduce, therefore can control reaction condition to control The hydrogenation depth of LCO controls the depth that two cycloaromatics and polycyclic aromatic hydrocarbon add hydrogen to be saturated in LCO, control as far as possible by two cyclophanes The a lot of cycloaromatics of hydrocarbon add hydrogen to mononuclear aromatics, in this way will plus hydrogen after LCO carry out reducing when catalytic cracking again reaction difficulty or The arene content in catalytically cracked gasoline is improved, the octane number of gasoline is improved.

3, in the present invention, the extraction logistics sheet that is obtained among the first hydrotreating reactor hydrogenation pretreatment catalyst bed Body has very high temperature and pressure, can be directly entered in newly-installed second hydrotreating reactor after mixing with LCO It is reacted, so that this thigh be made full use of to divide heat entrained by hydrotreated material, realizes the first hydrotreating reactor With the coupling operation of the second hydrotreating reactor.

4, in the present invention, the first hydrotreating reaction system is identical with the operating pressure of the second hydrotreating reaction system, Therefore a set of hydrogen desulphurization system and a set of hydrogen gas circulating system can be used in the high pressure hydrogen-rich gas in two systems, if into one Step two systems share a set of separation, fractionation (or stripping) system, then can significantly save equipment investment and operating cost.

Detailed description of the invention

Fig. 1 is principle process schematic diagram of the invention.

Fig. 2 is another principle process schematic diagram of the invention.

Wherein: logistics is extracted in 1- wax oil feedstock oil, the first hydrotreating reactor of 2-, the first hydrotreating of 3- out, and 4-LCO is former Material oil, 5- the first hydrotreating reactor recycle hydrogen, the first hydrotreating reactor of 6- generate logistics, and the second hydrotreating of 7- is anti- Device is answered, the second hydrotreating reactor of 8- generates logistics, the second high-pressure separator of 9-, 10- after-fractionating tower, 11- second plus hydrogen Handle naphtha, the second hydroprocessed diesel of 12-, 13- the second hydrotreating heavy distillate, 14- the second high-pressure separator hydrogen-rich Gas, 15- supplement hydrogen, the first high-pressure separator of 16-, the first fractionating column of 17-, the first hydrotreated naphtha of 18-, 19- first Hydroprocessed diesel, 20- the first hydrotreating heavy distillate, 21- the first high-pressure separator hydrogen-rich gas, 22- mixed high-voltage point From device, 23- mixing fractionating column, 24- mixed hydrogenation handles naphtha, and 25- mixed hydrogenation handles diesel oil, the processing of 26- mixed hydrogenation Heavy distillate, 27- mixed high-voltage separator hydrogen-rich gas.

Specific embodiment

The initial boiling point of wax oil raw material described in step a is 100~400 DEG C, and the end point of distillation is 405~650 DEG C.The wax oil is former Material oil can be one of straight-run gas oil, wax tailings, deasphalted oil that PETROLEUM PROCESSING obtains etc., the coal tar obtained from coal It is wherein several mixed to be also possible to them for one of oil, coal direct liquefaction oil, ICL for Indirect Coal Liquefaction oil, synthetic oil, shale oil etc. Close oil.

Step a, hydrotreating catalyst described in step b and step c is conventional wax oil hydrogenation processing catalyst.One As using VI B race and/or group VIII metal as active component, using aluminium oxide or silicon-containing alumina as carrier, group VIB metal is general For Mo and/or W, group VIII metal is generally Co and/or Ni.With the poidometer of catalyst, group VIB tenor is with oxide It is calculated as 10wt%~35wt%, group VIII metal content is calculated as 3wt%~15wt% with oxide, and property is as follows: specific surface 100 ~650m²0.15~0.6mL/g of/g, Kong Rongwei.Main catalyst have Fushun Petrochemical Research Institute develop 3936, 3996, FF-16, the hydrogenation pretreatment catalysts such as FF-26, FF-36, FF-46, FF-56 series are also possible to domestic and international catalyst The function of company's exploitation is similar to catalyst, and such as HC-K, HC-P of Uop Inc., TK-555, TK-565 of Topsoe company are catalyzed Agent and KF-847, KF-848 of Akzo company etc..Step a, hydrotreating catalyst described in step b and step c can be used Identical catalyst, the catalyst that can also be different.

Conventional Hydroprocessing conditions, generally reaction pressure can be used in the operating condition of hydrotreating described in step a 3.0MPa~19.0MPa, reaction temperature are 300 DEG C~450 DEG C, volume space velocity 0.2h when liquid^-1~6.0h^-1, hydrogen to oil volume ratio is 100:1~2000:1.

The entrance of first hydrotreating reactor described in step a, the i.e. top loading of top hydrogenation catalyst bed add Hydrogen protective agent, hydrogenation protecting agent are conventional hydrogenation protecting agent, and the usual gradation of protective agent bed uses 2 kinds or more of protective agent Kind.Conventional operating condition, generally reaction pressure 3.0MPa~19.0MPa can be used in protectant operating condition, reaction Temperature is 280 DEG C~420 DEG C, volume space velocity 0.5h when liquid^-1~20.0h^-1, hydrogen to oil volume ratio is 100:1~2000:1.

The mass ratio that the fraction of stream of extraction described in step a accounts for wax oil feedstock oil in terms of liquid phase is 5~95 wt%, excellent It is selected as 10~60 wt%.

Operating condition described in step b can be used conventional Hydroprocessing conditions, and generally reaction pressure 3.0MPa~ 19.0MPa, reaction temperature are 300 DEG C~450 DEG C, volume space velocity 0.2h when liquid^-1~6.0h^-1, hydrogen to oil volume ratio be 100:1~ 2000:1。

Separation described in step b generally comprises the first hydrotreating high-pressure separator and low pressure separator separates two Point.The isolated hydrotreating high pressure hydrogen-rich gas of its high-pressure separator and liquid, the isolated liquid of high-pressure separator Into low pressure separator.Low pressure separator is by the isolated hydrocarbon-rich gas of highly pressurised liquid product and low pressure liquid product.Hydrocarbon-rich gas Body is isolated to the hydrotreating gaseous product of needs.

Fractionation described in step b (or stripping) carries out in hydrotreating fractionating column (or stripper) system.Low pressure liquid Body product is fractionated in fractionating column obtains the first hydrotreated naphtha product, the first hydroprocessed diesel and the first hydrotreating Heavy distillat.

LCO raw material described in step c is the light cycle oil of catalytic cracking unit, and initial boiling point is 100~200 DEG C, the end point of distillation It is 320~400 DEG C.The virtues such as some coker gas oils, ethylene cracking tar, coal tar can also be blended in the LCO feedstock oil High one or more of the diesel oil distillate of hydrocarbon content.

Operating condition described in step c can be used conventional Hydroprocessing conditions, and generally reaction pressure 3.0MPa~ 19.0MPa, reaction temperature are 300 DEG C~450 DEG C, preferably 320 DEG C~410 DEG C, volume space velocity 0.2h when liquid^-1~6.0h^-1, Hydrogen to oil volume ratio is 100:1~2000:1.

Separation described in step c carries out in the second hydrotreating high-pressure separator and low pressure separator.Wherein plus hydrogen The isolated hydrotreating high pressure hydrogen-rich gas of high-pressure separator and liquid are handled, the isolated liquid of high-pressure separator enters Low pressure separator.Low pressure separator is by the isolated hydrocarbon-rich gas of highly pressurised liquid product and low pressure liquid product.Hydrocarbon-rich gas warp Second hydrotreating gaseous product of isolated needs.

Fractionation described in step c (or stripping) carries out in second hydrotreating fractionating column (or stripper) system.It is low Press liquid product is fractionated in fractionating column obtains the second hydrotreated naphtha product, the second hydroprocessed diesel and second plus hydrogen Heavy distillate.

First hydrotreating gas products described in step b and step c and the second hydrotreating gas products can be single It is solely used as product, mixed gas product can also be mixed into.

The first hydrotreated naphtha product and the second hydrotreated naphtha product described in step b and step c Mixing naphtha product can also be mixed into separately as product.

First hydroprocessed diesel described in step b and step c and the second hydroprocessed diesel can be separately as productions Product can also mix the feedstock oil as catalytic cracking unit.

First hydrotreating heavy distillat described in step b and step c and the second hydrotreating heavy distillat mixing are used as and urge Change the feedstock oil of cracking unit.

Separation described in step b and step c can handle high-pressure separator and mixing low pressure separator in mixed hydrogenation Interior progress, i.e., the generation logistics of two hydrotreating reactors are mixed into the same hydrotreating high-pressure separator and same Low pressure separator.The wherein isolated mixed hydrogenation processing high pressure hydrogen-rich gas of mixed hydrogenation processing high-pressure separator and mixed liquor Body, the isolated mixing liquid of mixed high-voltage separator enter mixing low pressure separator.Low pressure separator is mixed by high pressure liquid The isolated mixing hydrocarbon-rich gas of body product and mixing low pressure liquid product.Mixing hydrocarbon-rich gas is isolated to the mixing of needs Hydrotreating gaseous product.

Fractionation described in step b and step c (or stripping) can handle fractionating column (or mixing stripping in mixed hydrogenation Tower) it carries out in system.The fractionation in mixing fractionating column of mixing low pressure liquid product obtains mixed hydrogenation processing naphtha product, mixes Close hydroprocessed diesel and mixed hydrogenation heavy distillate.

Mixed high-voltage hydrogen-rich gas described in step b and step c can be used directly as recycle hydrogen, also can choose By recycled after desulphurization of recycle hydrogen system removing hydrogen sulfide.

In the present invention, the hydrogenation process in second hydrotreating reactor includes the two reaction ranks successively carried out Section, first stage of reaction carries out in the catalyst bed A containing hydrotreating catalyst, second stage of reaction containing plus hydrogen It handles in the catalyst bed B of catalyst and carries out.It can also include that LCO feedstock oil is cut into light fraction and double distilled in the present invention The process divided, the temperature of the cutting are 245 ~ 300 DEG C.First weighted BMO spaces object of the heavy distillat and step a extraction By catalyst bed A after stream mixing, catalyst bed A gained hydrotreating logistics passes through catalysis after mixing with the light fraction Agent bed B.

Further, in the second hydrotreating reactor second stage of reaction reaction temperature y₂Lower than first stage of reaction Reaction temperature y₁, preferably y₂Compare y₁Low 5-20 DEG C.

It is anti-by more hydrotreating catalysts in the cutting gained heavy distillat of LCO feedstock oil based on polycyclic aromatic hydrocarbon It answers, can achieve the purpose of control aromatic hydrogenation depth, and double ring arene passes through less hydrotreating catalyst in light fraction Reaction, can achieve the purpose that control aromatic hydrogenation depth simultaneously with heavy distillat, i.e. LCO after hydrotreating meets sulfur content Double ring arene and polycyclic aromatic hydrocarbon moderately add hydrogen to mononuclear aromatics simultaneously, can satisfy sulfur content after further catalytic cracking and want The catalytically cracked gasoline asked, and the octane number of gasoline can be improved.In addition, the second hydrotreating reactor internal catalyst bed layer B lower than catalyst bed A at a temperature of operated, be also beneficial to double ring arene add hydrogen saturation be converted into mononuclear aromatics reaction Progress.

In the present invention, the catalyst bed A and catalyst bed B be can be set in a hydrotreating reactor It is interior, or can be separately positioned in more than two hydrotreating reactors.First way is preferably used in the present invention.

In conjunction with Fig. 1, method of the invention is specific as follows: wax oil feedstock oil 1 is mixed into first plus hydrogen with recycle hydrogen 5 first Treatment reactor 2 extracts logistics 3, extraction out by extracting hydrotreating in the reaction stream of the first hydrotreating catalyst bed out Logistics after hydrotreating extraction logistics 3 goes successively to the hydrotreating catalyst bed of lower part, the hydrotreating extraction of extraction Logistics 3 enters the second hydrotreating reactor 7 after mixing with LCO feedstock oil 4, passes through the product of hydrotreating catalyst bed Stream 8, which enters in the second high-pressure separator 9, carries out gas-liquid separation, and isolated liquid enters fractionation in after-fractionating tower 10 and obtains Second hydrotreated naphtha 11, the second hydroprocessed diesel 12, the second hydrotreating heavy distillat 13, the first hydrotreating reaction Device production logistics 6, which enters in the first high-pressure separator 16, carries out gas-liquid separation, and isolated liquid enters the first fractionating column 17 It is high that middle fractionation obtains the first hydrotreated naphtha 18, the first hydroprocessed diesel 19, the first hydrotreating heavy distillat 20, second The first isolated hydrogen-rich gas 21 of the second hydrogen-rich gas 14 and the first high-pressure separator 16 for pressing separator 9 isolated is mixed It is further mixed with supplement hydrogen 15 as recycle hydrogen after circulating hydrogen compressor is pressurized after conjunction.

Illustrate the present invention program and effect below by embodiment.

Embodiment 1-4

Protective agent FZC-100, FZC-105 and FZC106 are China Petroleum and Chemical Corporation Fushun Petrochemical Research Institute The hydrogenation protecting agent of development and production；Catalyst FF-24 is China Petroleum and Chemical Corporation Fushun Petrochemical Research Institute The hydrotreating catalyst of development and production.

The main character of 1 wax oil feedstock oil of table

	Wax oil 1	Wax oil 2	LCO
				Density, g/cm³	0.904	0.937	0.935
Fraction range, DEG C	325~550	345~620	156~380
				Sulfur content, wt%	2.2	1.5	1.1
Nitrogen content, wt%	0.103	0.245	0.08
				Arene content, wt%	—	—	91.6

2 process conditions of table

2 process conditions of continued

3 test result of table

Wherein, the cutting temperature of LCO light fraction and heavy distillat is 270 DEG C.

Using flexible wax oil hydrogenation treatment process of the invention it can be seen from embodiment, by from the first hydrotreating A part of reaction stream of extraction in reactor, extraction logistics and LCO mixed hydrogenation process for producing fine quality catalytic cracking raw material, extraction Residue after logistics adds hydrogen reason logistics continuation hydrotreating to produce high-quality naphtha, hydrogenated diesel oil and the purpose for adding hydrogen heavy distillat, Fine quality catalytic cracking raw material is provided, production method is flexible.

Claims

1. a kind of flexible wax oil hydrogenation treatment process, includes the following steps:

B, the first hydrotreating logistics continuation of remainder is anti-by the first hydrotreating under hydroprocessing conditions in step a The lower part hydrotreating catalyst bed for answering device obtains the first hydrotreating reactor product stream by separation, fractionation or vapour The first hydrogenation gas product, the first hydrotreated naphtha product, the first hydrogenated diesel oil and first plus hydrogen heavy distillat are obtained after proposing；

C, in hydrotreating after the first hydrotreating logistics of the first hydrotreating reactor of extraction obtained by step a is mixed with LCO Under the conditions of by the hydrotreating catalyst bed of the second hydrotreating reactor, obtain the second hydrotreating reactor product Stream by separation, fractionation or stripping after obtain the second hydrogenation gas product, the second hydrotreated naphtha product, the second hydrogenated diesel oil and Second adds hydrogen heavy distillat.

2. hydroprocessing technique described in accordance with the claim 1, which is characterized in that step b and separation in step c and be fractionated The a set of separation of Cheng Gongyong, fractionating system.

3. hydroprocessing technique described in accordance with the claim 1, which is characterized in that the initial boiling point of the wax oil raw material be 100~ 400 DEG C, the end point of distillation is 405~650 DEG C.

4. hydroprocessing technique described in accordance with the claim 3, which is characterized in that the wax oil feedstock oil is selected from straight run wax In oil, wax tailings, deasphalted oil, coal tar, coal direct liquefaction oil, ICL for Indirect Coal Liquefaction oil, synthetic oil and shale oil etc. extremely Few one kind.

5. hydroprocessing technique described in accordance with the claim 1, which is characterized in that the initial boiling point of the LCO is 100~200 DEG C, the end point of distillation is 320~400 DEG C.

6. hydroprocessing technique described in accordance with the claim 1, which is characterized in that also blend coker gas oil, second in the LCO At least one of alkene pyrolysis fuel oil and coal tar.

7. hydroprocessing technique described in accordance with the claim 1, which is characterized in that the hydrotreating catalyst is with VI B race And/or group VIII metal is active component, using aluminium oxide or silicon-containing alumina as carrier；With the poidometer of catalyst, group VIB Tenor is calculated as 10wt%~35wt% with oxide, and group VIII metal content is calculated as 3wt%~15wt% with oxide；Its property As follows: specific surface is 100~650m²0.15~0.6mL/g of/g, Kong Rongwei.

8. hydroprocessing technique described in accordance with the claim 1, which is characterized in that the condition of hydrotreating described in step a are as follows: anti- Answer pressure 3.0MPa~19.0MPa, reaction temperature is 300 DEG C~450 DEG C, volume space velocity 0.2h when liquid^-1~6.0h^-1, hydrogen oil body Product is than being 100:1~2000:1.

9. hydroprocessing technique described in accordance with the claim 1, which is characterized in that the fraction of stream extracted out in step a is with liquid phase The weight percent that meter accounts for wax oil feedstock oil is 5~95 wt%, preferably 10~60 wt%.

10. hydroprocessing technique described in accordance with the claim 1, which is characterized in that hydroprocessing condition described in step b are as follows: Reaction pressure 3.0MPa~19.0MPa, reaction temperature are 300 DEG C~450 DEG C, volume space velocity 0.2h when liquid^-1~6.0h^-1, hydrogen oil Volume ratio is 100:1~2000:1.

11. hydroprocessing technique described in accordance with the claim 1, which is characterized in that the condition of hydrotreating described in step c are as follows: Reaction pressure 3.0MPa~19.0MPa, reaction temperature are 300 DEG C~450 DEG C, and preferably 320 DEG C~410 DEG C, volume is empty when liquid Fast 0.2h^-1~6.0h^-1, hydrogen to oil volume ratio is 100:1~2000:1.

12. hydroprocessing technique described in accordance with the claim 1, which is characterized in that in second hydrotreating reactor Hydrogenation process includes two stages of reaction successively carried out, and first stage of reaction is in the catalyst bed containing hydrotreating catalyst It is carried out in layer A, second stage of reaction carries out in the catalyst bed B containing hydrotreating catalyst.

13. hydroprocessing technique according to claim 12, which is characterized in that further include being cut into LCO feedstock oil gently The process of fraction and heavy distillat, the temperature of the cutting are 245 ~ 300 DEG C.

14. hydroprocessing technique according to claim 13, which is characterized in that the of the heavy distillat and step a extraction Pass through the catalyst bed A containing hydrotreating catalyst, catalyst bed A gained plus hydrogen after one weighted BMO spaces logistics mixing It handles after logistics is mixed with the light fraction through the catalyst bed B containing hydrotreating catalyst.

15. hydroprocessing technique according to claim 14, which is characterized in that the reaction temperature y of second stage of reaction₂It is low In the reaction temperature y of first stage of reaction_1。

16. hydroprocessing technique according to claim 15, which is characterized in that y₂Compare y₁Low 5-20 DEG C.

17. group technology according to claim 12, which is characterized in that the catalyst bed A and catalyst bed B It is arranged in a hydrotreating reactor, or is separately positioned in more than two hydrotreating reactors.