CN101120075B

CN101120075B - Process for producing ultra low sulfur and low aromatic diesel fuel

Info

Publication number: CN101120075B
Application number: CN2006800047726A
Authority: CN
Inventors: 刘益相; 金明俊; 赵仁镐; 朴哲佑; 金奎泰; 柳在旭; 申池宣; 朴城范
Original assignee: SK Innovation Co Ltd; SK Energy Co Ltd
Current assignee: SK Innovation Co Ltd; SK Energy Co Ltd
Priority date: 2005-02-17
Filing date: 2006-02-15
Publication date: 2011-11-16
Anticipated expiration: 2026-02-15
Also published as: CN101120075A; KR20060091990A; WO2006088314A1; KR101156370B1; JP2008530336A

Abstract

On the basis of the finding that hydrogenation reactivity with aromatics, as well as desulfurization reactivity, is closely correlated with the distillation properties of feedstock straight-run gasoil, the disclosed process is provided for separating the straight-run gasoil effluent from a crude distillation unit so as to afford a feedstock having properties good enough to be treated in a post-hydrodesulphurization process, thereby not only utilizing pre-existing hydrodesulphurization units to the maximum, but also significantly reducing aromatic levels. The process allows the production of diesel fuel meeting the WWFC category-4 standard, requiring the minimum possible investment in new facilities.

Description

The method of production super low sulfur and low aromatic diesel fuel fuel

Technical field

The present invention relates to a kind of method of producing ultra-low-sulphur diesel fuel by hydrogen addition catalyzed reaction.More specifically, the present invention relates to the method for the diesel oil fuel of a kind of production super low sulfur and low aromatic substances, wherein will separate from the straight-run diesel oil effluent of simple distillation device, obtain having the charging that good character is enough to handle in the technology after hydrogenating desulfurization, thereby not only farthest utilized already present hydrodesulfurization unit, also reduced the content of aromatic substances significantly.

Background technology

At present, although in order to improve Air quality and to prevent Global warming, developed many substitute energys energetically, but expected that gasoline and diesel oil fuel will continue to dominate automobile fuel market in considerable time, their consumption is all increasing every year gradually.But, in order to respond the action that improves global environment, the fuel that market demand is high-quality.Particularly, since 2005 or 2010, developed country and other country will be controlled at 50 or 10ppm to the sulphur content of diesel oil.For example, the sulphur content of the fuel of selling in European Union must be equal to or less than 50wppm.According to the regulation (beginning on June 1st, 2006 to carry out) of EPA, the sulphur content of diesel oil must reduce to and be equal to or less than 15wppm.After this, European and most of Asian countries wishes to formulate the regulation that is similar to EPA.Except sulphur, aromatic substance has become (comprising many rings) target of control.In fact, in some regulations that come into force at present, the total amount of regulation aromatic substance must reduce to certain level.For example, CARB (California AirResources Board) standard diesel oil and Sweden I class diesel oil (Swedish Class I diesel) the maximum aromatic substances total content of allowing is respectively 10 volume % and 5 volume %.Estimate in the near future to become more strict, perhaps will reformulate about some regulations of fuel performance (for example content of aromatic substances, distillating property etc.).

Since 2000,, developed new sulfur removal technology based on absorption, solvent extraction etc. for the production sulphur content is equal to or less than the ultra-low-sulphur diesel of 50/10ppm.But oil refinery company would rather use the sulfur removal technology of having developed, rather than develops new technology.Most of oil refinery company by improving desulfurization catalyst performance or improve technology and met regulation about sulphur content.But for proposing to relate to aspect aromatic substances or distillatory regulation prepares, except some new Technologies, people do not propose other as yet and substitute.At present, refinery is faced with new investment burden and huge control of the economy loss.

The example of representational Technology is included in the SynSat method in order to the content that reduces sulphur and aromatic substances of twentieth century early development, and the HDS-HAD method based on HAD (hydrogenation-dearomatization) catalyzer of exploitation about 2000.But these method and technologies all have following shortcoming: improved running cost owing to consume excessive hydrogen, needed huge investment to improve existing sulfur removal technology or introduce new processing unit.

Korean Patent discloses to have disclosed for 98-64338 number carries out hydrogenating desulfurization in the presence of the catalyzer that comprises inorganic carrier, group vib metal, group VIII metal and phosphorus, the sulphur content of straight-run diesel oil can be reduced to 100ppm or (step 1) below the 100ppm, if and allow at least a portion steam stripped stream from the effluent of step 1 with hydrogen by catalyst bed (wherein group VIII metal and halogen are immersed in the inorganic carrier), then the content of aromatic substances can be less than 5 volume %, and sulphur content can be less than 50ppm (preferred 10ppm).

United States Patent (USP) has disclosed a kind of production sulphur content for No. 6824673 and has been equal to or less than the method that 10wppm, total aromatic content are equal to or less than the diesel oil of 15 weight %.The operation that this method is intended to overcome conventional hydrogenating desulfurization/aromatic hydrocarbons saturation process needs the highly compressed problem, is included in first hydrodesulfurizationstages stages, handles the overhead product charging in the presence of hydrogen-containing treat gas and Hydrobon catalyst, makes the ground desulfurization of described feeding part.In second hydrodesulfurizationstages stages, in the presence of hydrogen-containing treat gas and Hydrobon catalyst, steam stripped liquid phase stream is handled equally then.After transferring to the aromatic substances hydrogenation stage, steam stripped liquid phase stream and hydrogen-containing treat gas are reacted in the presence of the aromatic substances hydrogenation catalyst, make aromatic substances hydrogenation.Therefore not but as mentioned above, this method need increase many operation stages, and has changed existing method to a large extent, overcomes the problem of ordinary method aspect the easy and economic benefit in technology.

Certainly, if above-mentioned expensive method is applicable to the characteristics of indivedual oil refinery companies, then can adopt for some companies.But, as in the situation of restriction sulphur content, the preferred dark sulfur removal technology that adopts oil refinery company to develop as far as possible.

In addition, the cut of expectation ultra-low-sulphur diesel shows light oil character, and has lower total aromatic content.In order to meet these expectations, diesel oil must meet 4 class standards of the WWFC shown in the following table 1 (worldwide fuel charter).

Table 1

Proportion, 60/60	0.82～0.84
		Sulphur content, ppm	5～10
Flash-point, °F	122 minutes
		Viscosity, 40 ℃ of centistokes	2.0～4.0
Particulate matter (PM), mg/litre	24 (maximum values)
		Cetane index	52.0 minute
Cetane value	55.0 minute
		T90，°F	608 (maximum values)
T95，°F	644 (maximum values)
		EP，°F	662 (maximum values)
Aromatic substances, weight %	15 (maximum values)

Therefore, need a kind of method of exploitation, guarantee to produce the diesel oil that satisfies WWFC 4 class standards, and can utilize the production unit of existing production ultra-low-sulphur diesel.

In addition, use the equipment of existing production ultra-low-sulphur diesel, utilize high boiling point heavy gas oil cut to produce the work in-process diesel product and consider it is favourable, wherein the 20-30 weight % of straight distillation light diesel oil in the high boiling point heavy gas oil cut straight-run diesel oil that is equivalent to from atmospheric distillation plant, obtain from economic aspect.

Summary of the invention

As mentioned above, proposed exploitation and considered advantageous method from economic aspect, with the direction of response exploitation diesel automobile engine, meeting the requirement of low sulfur content fuel, and cut shows light oil character and narrow fraction aromatic substances character.

According to the present invention, in order to utilize existing deep desulfuration method as much as possible, meet WWFC4 class diesel oil standard simultaneously, the inventor is to the character of addition reaction of hydrogen, the processing condition of particularly dark desulfurization zone, the distillating property of charging and depend on that the reflex action of catalyst property carried out thorough research found that the hydrogenation activity of aromatic substances and distillating property desulphurizing activated and charging straight-run diesel oil are closely related.That is to say that under dark desulfurization condition, be lower than certain specific temperature spot along with boiling range proceeds to, the sulphur content that is used as the straight-run diesel oil of hydrodesulfurization process charging can be reduced to 5ppm from about 10ppm easily, and its aromatic content can obviously reduce.In addition, the inventor has developed a kind of effective design, wherein separate the cut that has certain specific boiling point or be lower than this specific boiling point from straight-run diesel oil, as the charging of hydrodesulfurization process, simultaneously residual high boiling point last running being produced is the work in-process diesel product.

Therefore, the purpose of this invention is to provide a kind of method of producing diesel oil, this method can be under dark desulfurization condition, the aromatic content that obtains ultralow sulphur content simultaneously and obviously reduce.

Another object of the present invention provides the method for the diesel oil fuel of a kind of production super low sulfur and low aromatic substances, this method can farthest be utilized existing dark sulfur removal technology equipment, need minimum new investment, do not need to improve on a large scale existing processes equipment, do not need to introduce new processing unit yet.

Another object of the present invention provides a kind of method, wherein separates the solar oil cut that has certain specific boiling point or be lower than this specific boiling point from straight-run diesel oil, and as the charging of hydrogenating desulfurization, remaining diesel oil distillate is used to produce the work in-process diesel product simultaneously.

According to an embodiment, the invention provides a kind of method of producing the diesel oil fuel of low aromatic substances and super low sulfur, comprising: a), will be separated into each cut from the straight-run diesel oil effluent of simple distillation device according to the cut point that is set in the 320-360 ℃ of scope; B) be the 30-80 kg/cm at pressure ², temperature is that 320-380 ℃, liquid hourly space velocity are 0.1-2.0 hour ^-1And H ₂/ oil ratio example is 150-1000Nm ³Under the condition of/kl, in the presence of Hydrobon catalyst, make in cut point or each the cut fraction hydrogenation desulfurization below the cut point; C) recovery lives through the diesel oil distillate of the hydrogenating desulfurization of step b).

In a preferred improved procedure, described method also comprises by selective hydrogenation cracking, nitrogen absorption/dewaxing/hydrogenating desulfurization or hydrogenating desulfurization/process for dewaxing reforms at least a portion that boiling point is higher than the diesel oil distillate of cut point; From the logistics that after reforming step, obtains, separate the solar oil cut, the solar oil cut that obtains in this diesel oil distillate and the step b) is merged.From outflow stream, separate the charging that diesel oil distillate residue cut afterwards can be used as other process from last handling process.

By following feature, can reduce the content of aromatic substances significantly according to method of the present invention, and obtain the ultralow sulphur content that meets the standard that developed country carries out: under dark desulfurization condition, in the boiling spread that is set in straight run heavy gas oil from cut point in the straight-run diesel oil effluent of CDU or following and cut that obtain carries out hydrogenating desulfurization.Especially, the advantage of method of the present invention is farthest to have utilized existing dark sulfur removal technology equipment, and only needs minimum investment, does not need existing processes equipment is improved on a large scale, does not also need to increase new processing unit.In addition, the present invention can reduce the predetermined required temperature of reaction of sulphur content of realization, thereby the time limit of service that has prolonged catalyst system therefor has reduced the hydrogen amount that consumes.In addition, boiling point can also be converted into the work in-process diesel product of cleaning by suitable reforming process above the cut of cut point.

Description of drawings

Thereby Fig. 1 is expression handles the conceptual view of method that straight-run diesel oil farthest increases the efficient of aftertreatment according to of the present invention in independent process;

Fig. 2 is the figure that the distribution of nitrogen compound in straight-run diesel oil done with respect to boiling point;

Fig. 3 is an exemplary process figure, the scheme that expression is reformed above the diesel oil distillate of cut point to isolating boiling point from straight-run diesel oil by the selective hydrogenation cleavage method according to embodiments of the present invention;

Fig. 4 is an exemplary process figure, the scheme that expression is reformed above the diesel oil distillate of cut point to isolating boiling point from straight-run diesel oil by nitrogen absorption/dewaxing/hydrodesulfurizationprocess process according to another embodiment of the invention;

Fig. 5 is an exemplary process figure, the scheme that expression is reformed above the diesel oil distillate of cut point to isolating boiling point from straight-run diesel oil by hydrogenating desulfurization/process for dewaxing according to another embodiment of the invention;

Fig. 6 is the figure that single aromatic substance of obtaining among the embodiment 3 saturation exponent in basic (base) cut and 340 ℃-cut is done with respect to temperature of reaction;

Fig. 7 is the figure that shows the saturation exponent of single aromatic substance in basic cut, 340 ℃-cut and 360 ℃-cut that obtains among the embodiment 3;

Fig. 8 is that the saturation exponent of single aromatic substance of obtaining among the embodiment 4 is with respect to foundation CoMo catalyzer and CoMo-NiMo[90-10] figure that does of the temperature of reaction of catalyzer.

* the brief description * of Reference numeral

1,11,21: crude oil

2,12,22: than the light cut of straight-run diesel oil

3,13,23: boiling point is not higher than the cut of the straight-run diesel oil of cut point

4,14,24: boiling point surpasses the cut of the straight-run diesel oil of cut point

5,15,25: long residuum (AR)

6,16,26: boiling point is not higher than the cut of the hydrogenating desulfurization of cut point

7: the outflow logistics that obtains by selective hydrogenation cleavage method (HDC)

17: the outflow logistics that obtains by N absorption/dewaxing/hydrodesulfurizationprocess process

27: the outflow logistics that obtains by hydrogenating desulfurization/process for dewaxing

100,110,120: simple distillation device (CDU)

101,111,121: hydrogenating desulfurization (HDS) device

102: selective hydrogenation cracking (HDC) device

112: nitrogen absorption/dewaxing/hydrodesulfurization unit

122: hydrogenating desulfurization/dewaxing device

103,113,123: the diesel oil storing unit

Embodiment

Now preferred implementation of the present invention is described in detail, the example of these preferred implementations is illustrated in the accompanying drawings, and wherein same reference numerals is represented components identical.In order to explain the present invention, these embodiments are described below with reference to accompanying drawing.

Utilize existing dark desulfurizer to reduce in the solution of aromatic substances in searching, as mentioned above, according under dark desulfurization condition, the character of charging (the particularly heavy constituent of straight-run diesel oil) will greatly influence the unexpected discovery of the decline of the saturated or hydrogenation of aromatic substances and sulphur content, develop the present invention.Therefore, distillating property to charging is optimized, to overcome the shortcoming of ordinary method, that is to say, need huge fund input, improved running cost, and farthest utilize existing dark desulfurizer, remedy diesel oil fuel effectively by the introducing novel method and inevitably lose,, inevitably lose thereby remedy diesel oil to produce clean diesel (work in-process) product that sulphur and aromatic content meet WWFC 4 class standards.

In order to reach this purpose, emphasis has been considered following two aspects in the present invention.The most important thing is how high boiling fraction is separated, and handle, thereby farthest make aromatic substances hydrogenation and reduce sulphur content, wherein high boiling fraction normally by under the dark desulfurization condition to handle generation from the straight-run diesel oil effluent of simple distillation device (CDU), cause catalyst degradation, be difficult to the desulfurization performance that keeps stable.In addition, provide a kind of method, this method is utilized high boiling point diesel production work in-process clean diesel product residual after separation, thereby obtains great economic benefit.

With reference to figure 1, the viewpoint that farthest increases efficiency of post treatment by separating treatment straight run gas has been described.Fig. 2 has shown the figure that the distribution property of nitrogen (N) compound in straight-run diesel oil done with respect to boiling point.

According to ASTM D 86 standards, the boiling point of the straight-run diesel oil of the cut that obtains from CDU by fractionation is about 200-460 ℃, is about 200-390 ℃ usually.For as charging of the present invention, the sulphur content of straight-run diesel oil preferably is about 2.0 weight %, and nitrogen content is about 400ppm or less than 400ppm.

Term " hydrodesulfurization reaction or method " used in the literary composition is meant in the presence of catalyzer, can remove heteroatoms (particularly sulphur atom and nitrogen-atoms) and can make reaction of aromatic substances hydrogenant or method from charging by what hydrogen-containing treat gas carried out.

In the present invention, as the criteria for classification based on infusibility sulphur (RS) compound of dibenzothiophene (DBT) structure, the distribution property of each methyl substituents in TBP (true boiling point) fractionation scope is the important factor of determining the temperature standard of separation straight-run diesel oil.Representational RS compound is a dibenzothiophene derivatives, such as 4-MDBT, 4, and 6-dimethyl Dibenzothiophene etc.

In the RS compound, the DBT (1C-DBT) that has a methyl substituents or do not have a methyl substituents is very easy to desulfurization, and can be distributed in 320 ℃ or be lower than 320 ℃ by fractionation.When having two methyl substituents (2C-DBT), DBT mainly is distributed in about 320-340 ℃ the temperature range, when having three methyl substituents (3C-DBT), mainly be distributed in about 340-360 ℃ the scope, if have four or more a plurality of methyl substituents, then mainly be distributed in the scope that is higher than 360 ℃.

As shown in Figure 2, at 360 ℃ or be higher than in 360 ℃ the distillation range, the concentration of two kinds of nitrogen compounds all obviously influences 4, the dark desulfurization of 6-DMDBT, and RS compound such as high boiling point benzo DBT increase sharply.Especially, though to dark desulfurization studies show that boiling point is higher than 360 ℃ cut and just exists with trace, still can worsen desulfurization condition, particularly cause temperature of reaction to increase sharply, make the time limit of service of catalyzer shorten to 1 year or 2 years from 4 years or 5 years.

According to the present invention, consider that above-mentioned analytical results selects the cut point of suitable straight-run diesel oil.As shown in Figure 1, according to 380 ℃ boiling point, straight-run diesel oil is divided into straight distillation light diesel oil and straight run heavy gas oil usually.However, it should be understood that this differentiation is from considering not to be intended to limit the present invention in order to set for simplicity in full.

In the embodiment shown in Fig. 1 a, straight distillation light diesel oil can be divided into the cut that boiling point is not less than and is not higher than the boiling point (being cut point) of selection.The cut that boiling point surpasses the boiling point of selecting is the last running of straight distillation light diesel oil and the mixture of straight run heavy gas oil, makes the independent back reforming process of this mixture experience.In the embodiment of Fig. 1 b, straight distillation light diesel oil is divided into the cut that boiling point is not less than and is not higher than the boiling point of selection.Make boiling point surpass the independent back reforming process of cut experience of the boiling point of selection.

Therefore, in all straight-run diesel oils, can use existing treatment unit under dark desulfurization condition, the cut that boiling point is lower than the boiling point of selection carries out hydrogenating desulfurization to be handled.Simultaneously, in independent back reformer, boiling point is handled above at least a portion of the cut of the boiling point of selecting.Therefore, compare, can greatly reduce required equipment input, thereby solve the economic problems of the outer investment of total value aspect according to the program of the present invention with the common process technology.

According to the present invention, consider the distillating property of straight-run diesel oil, will be set in about 360 ℃ of maximum as the cut point of the standard of separating straight-run diesel oil.If desired, cut point can be reduced to about 320 ℃.Therefore, preferably cut point is set in about 320 ℃ to 360 ℃ scope.When considering the distribution property of RS compound, more preferably cut point is set in about 340 ℃.

In hydrodesulfurizationstages stages, handle the cut that boiling point is lower than the cut point of selection.In this regard, typical dark desulfurization condition is preferred, because this condition can farthest be utilized conventional device.The dark desulfurization condition of this class can comprise: reaction pressure is the 30-80 kg/cm ², temperature of reaction is about 320-380 ℃, and liquid hourly space velocity (LHSV) is about 0.1-2.0 hour ^-1, H ₂/ oil ratio example is about 150-1000Nm ³/ kl.Preferably, the boiling point dark desulfurization that is lower than the cut of cut point is about the 50-70 kg/cm in reaction pressure ³, temperature of reaction is about 350-370 ℃, and LHSV is about 0.5-1.0 hour ^-1, H ₂/ oil ratio example is about 300-500Nm ³Carry out under the condition of/kl.Under these conditions, carry out hydrogenating desulfurization, sulphur content is reduced to below the 10ppm, preferably be reduced to below the 5ppm.When according to certain specific boiling point (for example about 340 ℃), particularly consider the distribution property of RS compound, when charging straight-run diesel oil is separated, can so that to the sulphur content of the cut that is lower than this boiling point be reduced to 5ppm or below the 5ppm, be reduced to 1-2ppm in some cases.Can obviously find out from the data of following examples, can reduce more than 18 ℃ or 18 ℃ making sulphur content be reduced to the required temperature of reaction of conformance with standard (for example, 10pppm or 10ppm are following).

The typical catalyst that is used for hydrogenating desulfurization comprises porous infusibility carrier (for example gama-alumina, silicon-dioxide, zeolite or their combination), and deposition is selected from first metal component and second metal component that is selected from Co, Ni, W and their combination of Mo on this carrier.Gross weight in catalyzer is a benchmark, and the consumption of first metal component is about 10-30 weight %, preferably is about 12-20 weight %, and the consumption of second metal component is about the 2-10 weight % of catalyst weight, is more preferably the 3-7 weight % of catalyst weight.

As mentioned above, one of most important characteristic of the present invention is that when the cut that is lower than predetermined boiling point that obtains from straight-run diesel oil carried out hydrogenating desulfurization under dark desulfurization condition, their aromatic content and sulphur content can both obviously be reduced.Especially, for the content of the aromatic substances that meets WWFC 4 class standards regulations should be equal to or less than 15 weight %, second metal component of catalyzer preferably comprises the combination (for example CoMo-NiMo or CoMo-NiW) of two or more metal ingredients, rather than independent a kind of composition.But, it should be noted that, even when second metal component by independent a kind of composition (for example CoMo) when forming, also comprise the polycyclic aromatic material being lower than the isolated cut of certain specific cut point, for example two rings or more polycyclic aromatic substances, their content is reduced to 2 weight % or below the 2 weight %, estimates that this numerical value is the standard of future to the polycyclic aromatic substances content.

According to the present invention, at the boiling point of selecting or be lower than cut that the boiling point of selection obtains under dark desulfurization condition during the experience hydrogenating desulfurization, they can contain 5ppm or less than the sulphur of 5ppm and 15 weight % or less than the aromatic substances of 15 weight %.

On the other hand, the cut that the boiling point that obtains is surpassed the cut point of selecting is transferred in the reforming process of back, but at the diesel oil fuel of this production super low sulfur and low aromatic substances.Can carry out these reforming processes by three kinds of following embodiments.In this regard, Fig. 3 to Fig. 5 has shown selective hydrogenation cleavage method, nitrogen absorption/dewaxing/hydrodesulfurizationprocess process and hydrogenating desulfurization/process for dewaxing respectively, and the diesel oil distillate that can be higher than predetermined cut point by these methods to the boiling point that obtains from straight-run diesel oil is reformed.

In simple distillation device 100,110,120, by fractionation

crude oil

1,11,21 is separated into each component according to boiling point.The

cut

2,12,22 lighter than straight-run diesel oil separates in addition with the

cut

5,15,25 heavier than straight-run diesel oil, at cut point or be lower than the

cut

3,13,23 that cut point obtains be transferred in the hydrodesulfurization unit 101,111,121 that moves under dark desulfurization condition from straight-run diesel oil.Retrieve cut 6,16,26 effluents, introduce in the diesel oil storing unit 103,113,123 from hydrodesulfurization unit.

Simultaneously, by the back reforming

method cut

4,14,24 that boiling point is higher than cut point is converted into the more cut of high value.According to the present invention, cut as much as possible is restructured as meets the required low aromatic substances and the diesel oil fuel of super low sulfur standard, merge in the diesel oil storing unit with

cut

6,16,26 then.For the shortcoming (being cryogenic properties) that overcomes high boiling fraction, can carry out (hydrogenation) dewaxing process as shown in Figure 4 and Figure 5.Representative reactions condition in selective hydrogenation cracker 102, nitrogen absorption/dewaxing/hydrodesulfurization unit 112 and hydrogenating desulfurization/dewaxing device 122 is summarised in the following table 2.

Table 2

¹: in this HDC method, can use conventional silica-alumina or zeolite based catalysts.

²: in this N adsorption method, can use conventional silica gel, silica-alumina or zeolite-based adsorbent.

³: in this process for dewaxing, can use conventional zeolite based catalysts.

⁴: in this HDS method, can use above-mentioned Hydrobon catalyst.

In addition, before or after carrying out back reformation processing, can also carry out hydrogen treatment or hydrofinishing process, thereby improve the color or the stability of product.

The present invention may be better understood by following examples, and this embodiment is illustrative, should not be construed as restriction the present invention.

Embodiment 1

In this embodiment, the character of each used specimen material and change according to the productive rate of the straight distillation light diesel oil of cut point has been described.All following specimen materials are by the preparation of identical straight distillation light diesel oil, except the sample in last hurdle of table 3 is a mixture with straight run heavy gas oil.In table 3, provided main character by the sample for preparing according to the isolating cut of the TBP cut point of 340 ℃ and 360 ℃.In table 4, summed up the productive rate of solar oil (LGO) according to different cut points.From the data of table 4 as can be seen, 10 ℃ of the every variations of TBP cut point estimate that productive rate changes about 5.6 volume %.But,, be not intended to limit the scope of the invention so productive rate changes because the character of cut, composition and productive rate depend on the character of used crude oil.

Table 3

The character of straight-run diesel oil

¹: the 340 ℃+cut that obtains from straight distillation light diesel oil

²: the 340 ℃+cut that obtains from straight distillation light diesel oil and the mixture of straight run heavy gas oil

³: cloud point/pour point

⁴: simulation distil

Table 4

Solar oil (LGO) productive rate according to the TBP cut point

The TBP cut point	?330	340	360	370	380
						LGO, volume %	?65	71	82	88	94

Embodiment 2

Three kinds of solar oil samples of analytical table 3 under the listed experiment condition of following table 5 (basic, 340 ℃-, 360 ℃-) nature of devulcanization.In continuous reactor, carry out reaction experiment, make sulphur content reduce to required desulfurization temperature of 10ppm and hydrogen consumption with measurement.The result is summarised in the following table 6.

Table 5

Experiment condition

Catalyzer	The CoMo-base	Catalyst volume	55cc
				H ₂Dividing potential drop	58 kg/cm ²	H ₂/ oil	220Nm ³/kl
The Rxn temperature	320-370℃	LHSV	1.0 hour ^-1

Table 6

	Substantially	360℃-	340℃-
				Rxn temperature 10ppm, ℃	363	345	335
The hydrogen that consumes, Nm ³/kl	58	56	52

Can obviously find out from the data of table 6, when cut that the boiling point that obtains from straight distillation light diesel oil is not higher than the cut point that is set in 320-340 ℃ carries out hydrogenating desulfurization under dark desulfurization condition, can make sulphur content be reduced to 10ppm or reduce more than 18 ℃ or 18 ℃ less than the required temperature of reaction of 10ppm.Consider this result, compare in the situation of not carrying out carrying out in the hydrogenating desulfurization under the isolating situation according to distillating property with straight-run diesel oil that expection the present invention can prolong 2 years at most with the time limit of service of catalyzer, the consumption of hydrogen reduces 10% at most.

Embodiment 3

In following table 7, provided the variation of the aromatic substances composition of control among the embodiment 2.In addition, measure the saturation exponent of single aromatic substance of all basic cuts, 340 ℃-cut and 360 ℃-cut with the variation of temperature of reaction.

Table 7

The content of aromatic substances

The saturation exponent of single aromatic substances:

(hydride conversion rate)=[(A+B+C)-D]/(A+B+C)

A: the concentration of two aromatic substances (weight %) in the charging

B: the concentration of two aromatic substances (weight %) in the product

C: the concentration of single aromatic substances (weight %) in the charging

D: the concentration of two aromatic substances (weight %) in the product

As shown in Figure 6, the cut point that straight-run diesel oil is lower obtains the higher hydrogen transformation efficiency of single aromatic substance.

Fig. 7 shows the saturation exponent of single aromatic substance in each basic cut, 340 ℃-cut and 360 ℃-cut.In identical temperature of reaction, the hydride conversion rate of aromatic substance increases with the decline of the distillation temperature of straight-run diesel oil.But as shown in Figure 7, being increased in of hydride conversion rate has slowing down to a certain degree in 360 ℃-340 ℃ the scope.It is believed that slowing down of advancing the speed is because the hydrogen activity restriction of CoMo catalyzer causes.

Embodiment 4

Do not use to contain the catalyzer of CoMo (100%), contain CoMo: NiMo (9: 1) makes 360 ℃-cut as the catalyzer of activeconstituents LGO desulfurization under the condition identical with embodiment 2 and use as activeconstituents.As a result, the aromatic content of product obviously descends.In order to compare, analyze the hydride conversion rate of CoMo (100%) catalyzer and CoMo: NiMo (9: 1) catalyzer, the results are shown among Fig. 8.As shown in Figure 8, CoMo: NiMo (9: 1) catalyzer is compared with the CoMo catalyzer, transformation efficiency can be improved up to about 8% down in identical temperature of reaction (360 ℃).

Can find out obviously that from the data of table 7 under given dark desulfurization condition, alternative catalysts can make the content of aromatic substances be reduced to below 15% or 15%.Similarly, add NiMo and can obviously improve hydrogenation activity, even also be like this under low reaction temperatures.

Embodiment 5

In order to determine whether cut can be produced diesel oil fuel by reforming method (comprising hydrocracking), and reaction experimentizes under the condition shown in the following table 8.Provided the result in the following table 9.

Table 8

340 ℃+(1) ¹Reaction conditions

Catalyzer	HDT/HDC/HDT ²	Charging	340℃+(1)
				H ₂The dividing potential drop kg/cm ²	95	H ₂/ oil, Nm ³/kl	1200
Rxn temperature ℃	384/392/200-360	LHSV, hour ^-1	0.65

¹: with the import is benchmark, uses all three steps.Consider the calorific value of each reactor, by inlet temperature and H ₂Quencher speed is determined the temperature of each step, because the reaction in each reactor is heat release.Temperature of reaction is the weight average reaction bed temperature (WABT) of each reactor.

²: hydrotreatment or hydrofining step.This step can use conventional heat exchange network to carry out at low temperatures, to improve the tint permanence and the stability of product.

Table 9

As shown in table 9, the diesel oil fuel of (15 weight % or less than 15 weight %) and ultra-low sulfur (10ppm or less than 10ppm) is handled and is produced and have low aromatic content in the reformation of cut that the boiling point that obtains from straight-run diesel oil is higher than the cut point of selection.In addition, the rate of recovery that is recycled to the high boiling fraction of diesel oil distillate equals 82 volume %, therefore shows that loss of yield is little of 6%.Therefore, if consider extra petroleum naphtha production, method of the present invention makes moderate progress aspect macroeconomic.

Embodiment 6

For whether check can be by as shown in Figure 4 absorption with nitrogen component from by in being higher than the cut that cut point obtains, removing effectively the straight-run diesel oil, be that 70 ℃, LHSV are 1.5 hours in temperature ^-1With pressure be 7 kg/cm ²Condition under with 340 ℃+(1) cut of preparation in the silica adsorbent Processing Example 1 of modification.Measuring the remove rate of nitrogen from cut is 78% (total nitrogen content is reduced to 116ppm from 526ppm).

Therefore, estimate to make cut meet the requirement of cryogenic properties and sulphur content aspect according to improved Hydrodewaxing of the present invention and Hydrobon catalyst by adopting.

Embodiment 7

In order to check when handling whether can produce high-quality diesel oil fuel by heavy gas oil in conjunction with straight distillation light diesel oil, 340 ℃+(2) cut of test implementation example 1 preparation under the given condition of following table 10.

Table 10

340 ℃+(2) ¹Reaction conditions

Catalyzer	HDT/HDC/HDT	Charging	340℃+(2)
				H ₂The dividing potential drop kg/cm ²	108	H ₂/ oil, Nm ³/kl	1200
Rxn temperature ℃	384/392/200-360	LHSV, hour ^-1	0.65

¹: except hydrogen dividing potential drop difference, identical among other condition and the embodiment 5.

Table 11

With listed similar in the table 9 of embodiment 5, the data of table 11 show, can be produced and had low aromatic content the diesel oil fuel of (15 weight % or less than 15 weight %) and ultra-low sulfur (10ppm or less than 10ppm) by the mixture of the high boiling fraction of heavy gas oil and straight-run diesel oil.

Preferred implementation according to the present invention has been described embodiment.However, it should be understood that these contents are not used for restriction to explanation of the present invention.Specification sheets of the present invention and claim are understood to include all changes and the modification in the true scope of the present invention.

Claims

1. produce the method for hanging down aromatics and ultra-low-sulphur diesel fuel for one kind, it comprises:

A) according to the cut point that is set in the 320-360 ℃ of scope, will be separated into each cut from the straight-run diesel oil effluent of simple distillation device;

B) comprising that pressure is the 30-80 kg/cm ², temperature is that 320-380 ℃, liquid hourly space velocity are 0.1-2.0 hour ^-1And H ₂/ oil ratio example is 150-1000Nm ³Under the condition of/kl, in the presence of Hydrobon catalyst, make at cut point or each cut below the cut point and carry out hydrogenating desulfurization; And

C) recovery lives through the diesel oil distillate of the hydrogenating desulfurization of step b),

Wherein, the sulphur content of the diesel oil distillate that obtains after step b) is equal to or less than 10ppm, and aromatic content is equal to or less than 15 weight %.

2. the method for claim 1 is characterized in that, the boiling point of described straight-run diesel oil is 200 ℃ to 460 ℃.

3. method as claimed in claim 2 is characterized in that, the sulphur content of described straight-run diesel oil is equal to or less than 2 weight %, and nitrogen content is equal to or less than 400wtppm.

4. the method for claim 1 is characterized in that, described cut point is 340 ℃.

5. the method for claim 1 is characterized in that, the sulphur content of the diesel oil distillate that obtains after step b) is equal to or less than 5ppm, and aromatic content is equal to or less than 15 weight %.

6. the method for claim 1, it is characterized in that, used Hydrobon catalyst comprises porous infusibility carrier in the step b), on this carrier, deposit first metal component that is selected from Mo and second metal component that is selected from Co, Ni, W and their combination, gross weight in described catalyzer is a benchmark, and the content of described first metal component and second metal component is respectively 10-30 weight % and 2-10 weight %.

7. method as claimed in claim 6 is characterized in that, described Hydrobon catalyst comprises the combination as the CoMo of catalytically-active metal component and NiMo or CoMo and NiW.

8. method as claimed in claim 6 is characterized in that, described carrier is by gama-alumina, silicon-dioxide, zeolite or their combined preparation.

9. the method for claim 1 is characterized in that, described method also comprises:

By (i) selective hydrogenation cracking process, (ii) nitrogen absorption/dewaxing/hydrodesulfurization or (iii) hydrogenating desulfurization/wax fractionation process, at least a portion that isolating boiling point from step a) is higher than the diesel oil distillate of cut point is reformed; And

From the logistics that after reforming step, obtains, separate diesel oil distillate, the solar oil cut that obtains in this diesel oil distillate and the step b) is merged.

10. method as claimed in claim 9 is characterized in that, step (i) is comprising that pressure is the 40-120 kg/cm ², temperature is that 340-410 ℃, liquid hourly space velocity are 0.5-3.0 hour ^-1And H ₂/ oil ratio example is 400-1500Nm ³Carry out under the condition of/kl.

11. method as claimed in claim 9 is characterized in that, step is (ii) carried out under the following conditions: for nitrogen absorption, pressure is the 5-20 kg/cm ², temperature is that 40-200 ℃, liquid hourly space velocity are 1.0-3.0 hour ^-1For dewaxing, pressure is the 30-80 kg/cm ², temperature is that 300-410 ℃, liquid hourly space velocity are 0.5-3.0 hour ^-1And H ₂/ oil ratio example is 200-1000Nm ³/ kl; For hydrogenating desulfurization, pressure is the 30-80 kg/cm ², temperature is that 300-410 ℃, liquid hourly space velocity are 0.5-3.0 hour ^-1And H ₂/ oil ratio example is 200-1000Nm ³/ kl.

12. method as claimed in claim 9 is characterized in that, step is (iii) carried out under the following conditions: for hydrogenating desulfurization, pressure is the 30-80 kg/cm ², temperature is that 300-410 ℃, liquid hourly space velocity are 0.5-3.0 hour ^-1And H ₂/ oil ratio example is 200-1000Nm ³/ kl; For dewaxing, pressure is the 30-80 kg/cm ², temperature is that 300-410 ℃, liquid hourly space velocity are 1.0-3.0 hour ^-1And H ₂/ oil ratio example is 200-1000Nm ³/ kl.

13. method as claimed in claim 9 is characterized in that, the sulphur content of isolating solar oil cut is equal to or less than 10ppm the logistics that obtains after reforming step, and aromatic content is equal to or less than 15 weight %.