JPH08183964A - Hydrotreating method for raw materials for fluid catalytic cracking - Google Patents

Abstract

(57) [Summary] [Object] To provide a hydrotreatment method capable of supplying a highly reactive raw material for fluid catalytic cracking in a fluid catalytic cracking reaction. [Structure] Depressurized gas oil fraction or atmospheric distillation residual oil fraction or a mixture thereof is subjected to demetalization, decarbonization, desulfurization and denitrification in the first hydrotreatment zone at a relatively high temperature to give a treated oil first. A method for hydrotreating a raw material for catalytic cracking of high quality and high reactivity by providing nuclear hydrogenation of two or more aromatic rings in a second hydrotreatment zone having a reaction temperature lower than that of the hydrotreatment zone. [Effect] The hydrotreated oil obtained by the present invention has high reactivity in a catalytic cracking reaction and a high conversion rate, and thus a light oil can be obtained in a high yield.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for hydrotreating a raw material for fluid catalytic cracking (hereinafter referred to as "raw material for FCC", if necessary). More specifically, the polycyclic aromatic compound in the raw material is used as a nucleus. The present invention relates to a hydrotreatment method for producing a high quality FCC raw material which is removed by hydrogenation and hydrocracking. ADVANTAGE OF THE INVENTION According to this invention, the raw material for FCC which can achieve high conversion and high light oil yield in FCC can be provided.

[0002]

2. Description of the Related Art A fluid catalytic cracking unit is extremely important in terms of technology and economy as a petroleum refining process for producing high-value-added light fuel oil. Infinite development continues to improve the yield of minutes.

However, sulfur is contained in a vacuum gas oil fraction conventionally used as a raw material for fluid catalytic cracking and an atmospheric distillation residue fraction used recently as a measure for increasing the value of heavy oil. Various kinds of complex compounds such as compounds, nitrogen compounds, metal components and polycyclic aromatic compounds are contained, and these impede the reactivity of the catalytic cracking device, leading to a reduction in product yield.

Therefore, a hydrotreating method has been proposed as a pretreatment before the feed oil is fed to the catalytic cracking apparatus (for example, Japanese Patent Laid-Open No. 41391/1990), and a commercial hydrotreating process is also operated. There is.

However, in the conventionally proposed hydrotreating method, it is necessary to simultaneously remove not only the metal components contained in the feed oil but also various compounds, especially polycyclic aromatic components, because the reaction of each compound is different. Since it is difficult and there are many residual compounds that poison the catalyst, it has not been sufficiently achieved to improve the reactivity of FCC.

[0006]

Under the above circumstances, the present invention provides metal components, residual carbon components, sulfur compounds, nitrogen compounds in addition to vacuum gas oil fractions and atmospheric distillation residue fractions,
An object of the present invention is to realize a hydrotreating method capable of efficiently removing all of polycyclic aromatic hydrocarbons and providing a highly reactive raw material for FCC.

[0007]

Means for Solving the Problems As a result of intensive studies conducted by the present inventors to develop a hydrotreating method capable of providing a highly reactive raw material for FCC as described above, the hydrotreating zone is It is assumed to be composed of two steps, one step and the second step, and in the first step, the reaction is performed at a relatively high temperature,
After efficiently carrying out the removal of metal content, residual carbon content, desulfurization, and denitrification reaction, in the second step, the reaction is carried out at a reaction temperature lower than the reaction temperature of the first step, and nuclear hydrogenation of polycyclic aromatics and It was found that the above problems can be achieved by carrying out hydrocracking, and the present invention was completed based on this finding.

Thus, according to the present invention, a reduced pressure gas oil fraction, an atmospheric distillation bottom oil fraction, or a mixture thereof is used in the first hydrotreatment zone so that the pore volume of 60 Å or more is the total pore volume. 40% or more of
In the presence of a hydrotreating catalyst having a high denitrification activity, under the hydrotreating reaction conditions, contact with hydrogen produces a first hydrotreated oil from which sulfur and nitrogen compounds have been removed, The hydrotreated oil is introduced into the second hydrotreating zone and is contacted with hydrogen at a reaction temperature lower than the reaction temperature of the first hydrotreating zone in the presence of a hydrotreating catalyst having high aromatic nucleus hydrotreating activity. This provides a hydrotreatment method for a fluid catalytic cracking feedstock, which comprises producing a second hydrotreated oil from which a polycyclic aromatic component having two or more rings is removed.

Furthermore, as a preferred embodiment of the present invention, the following hydrotreatment methods are provided.

That is, a vacuum gas oil fraction, an atmospheric distillation bottom oil fraction or a mixture thereof is used in the first hydrotreating zone with a refractory inorganic oxide as a carrier and a nickel-molybdenum component and / or cobalt as a hydrogenation active component. -Hydrolysis reaction is carried out in the presence of a hydrotreating catalyst that has a molybdenum component and has a pore volume of 40% or more of the total pore volume with a pore diameter of Å or more. By contacting with hydrogen under the conditions, the first hydrotreated oil from which the metal content, the residual carbon content, the sulfur content and the nitrogen content have been removed is produced, and the first hydrotreated oil is subjected to the second hydrotreatment. Introduced into the treatment zone, carrying a hydrogenation active component on the refractory inorganic oxide, and in the presence of a hydrotreating catalyst having a large total pore volume ratio, lower than the reaction temperature of the first hydrotreatment zone. Temperature is 280 ° C-380 ° C
The hydrotreating method according to claim 1, which comprises producing a second hydrotreated oil from which two or more polycyclic aromatic components have been removed by contacting with hydrogen at a reaction temperature of 1. And a second hydrotreatment zone, a separator is installed between the hydrogen gas and the circulating gas stripping hydrogen sulfide and ammonia, the hydrotreating method according to claim 1, and the first hydrotreated oil to the first hydrogen The hydrotreating method according to claim 1, which comprises lowering the reaction temperature of the second hydrotreating zone by heat exchange with a feed oil to be introduced into the hydrotreating zone, or by joining the second hydrotreated oil. , And the catalyst amount ratio of the second hydrotreatment zone castle is 50% of the total catalyst amount.
% To 10% is provided. Hereinafter, the present invention will be described in detail.

In the present invention, typical properties of the reduced pressure gas oil fraction and the atmospheric distillation residual oil fraction used when preparing the FCC raw material are as follows.

Vacuum gas oil fraction (VGO) Boiling range: 550. F (288 ° C) -1100. F (5
93 ° C.) Sulfur compound content (as S): 1 wt% -3 wt% Nitrogen compound content (as N): 200 ppm-200
0 ppm Ni + V content: 0.1 ppm-10 ppm Residual carbon content (CCR) content: 0.1 wt% -2 wt% atmospheric distillation residual oil fraction (RC) Boiling range: 650 ° F or higher Sulfur compound content ( S): 1 wt% -5 wt% Nitrogen compound content (as N): 500 ppm-300
0 ppm Ni + V content: 0.5 ppm-700 ppm Residual carbon content: 1 wt% -20 wt% As the FCC raw material to be treated by the hydrotreating method according to the present invention, the above-mentioned reduced pressure gas oil fraction and atmospheric distillation residue are used. Not limited to oil fractions, other petroleum refining processes, such as products obtained by thermal cracking equipment such as visbreaking, coking, or products obtained from fluid catalytic cracking equipment also fall within the above boiling range. It can be used if applicable.

Next, the hydrotreating zone of the present invention will be described.

In the present invention, a relatively high reaction temperature is adopted in the first hydrotreating zone so that the demetalization, decarbonization, desulfurization and denitrification reactions are efficiently carried out. In the first hydrotreating zone, the preferred reaction temperature is 28
The temperature is in the range of 0 ° C to 450 ° C, and the more preferable reaction temperature is in the range of 300 ° C to 430 ° C.

The reaction pressure is in the range of 2 MPa to 15 MPa, and the preferable reaction pressure is 3000 kpa-12.
It is in the range of 000 kpa. Raw oil flow rate is 0.5 V /
It is in the range of H / V to 4.5V / H / V, and the preferable feed oil flow rate is in the range of 0.6V / H / V to 2.5V / H / V. Further, the flow rate of hydrogen gas is 100 Nl / source oil 1 to
It is in the range of 1000 Nl / source oil l, and the preferable hydrogen gas flow rate is in the range of 150 Nl / l to 600 Nl / l. Hydrogen sulfide produced by the hydrocracking reaction, ammonia or a lower hydrocarbon is mixed in hydrogen gas, and it can be introduced into the second hydrotreatment zone without gas-liquid separation, but after gas-liquid separation, Ammonia hydrogen sulfide and the like can be removed. In this case, the hydrotreated oil removes lower hydrocarbons, hydrogen sulfide, ammonia and the like as stripping, so that the desulfurization reaction and denitrification reaction, especially the dearomatization rate can be further improved.

The hydrotreating catalyst used in the first hydrotreating zone can achieve various purposes such as demetalization, decarbonization, desulfurization and denitrification, and a catalyst having a combination of functions is preferable. .

A catalyst having a large total pore volume ratio and a relatively large pore diameter is preferable in order to smoothly carry out demetalization and deresidual carbon content, and it is effective to install it in the introduction part of the reaction zone. Is. A preferred hydrotreating catalyst is
A refractory inorganic oxide is used as a carrier and a hydrogenation active component is supported, and the volume of pores having a pore diameter of 60 Å or more is 80% or more of the total pore volume.

As the refractory inorganic oxide, silica, alumina, titania, silica-alumina, alumina-titania, alumina-zirconia, silica-magnesia, etc. are used, and vanadium, molybdenum, tungsten, nickel are used as hydrogenation active components. , Cobalt, palladium,
Platinum, rhenium, ruthenium, rhodium, etc. are used,
These are used by being carried on a carrier.

The properties of the first hydrotreated oil obtained from the first hydrotreated zone are as follows.

Sulfur compound content (as S): 0.3 wt% or less Nitrogen compound content (as N): 600 wt ppm or less Ni + V content: 10 ppm or less Residual carbon content: 2 wt% or less Polycyclic aromatic Group component content: 35 wt% or less The reaction temperature in the second hydrotreating zone is lower than the reaction temperature in the first hydrotreating zone, usually 280 ° C.
It can be adopted in the range of up to 380 ° C. The preferred reaction temperature is in the range of 300 ° C to 360 ° C, but is selected in relation to the reaction temperature of the first hydrotreating zone.

The reaction pressure is 2000 kpa to 20000.
The reaction pressure adopted in the range of kpa is preferably 30
The range is from 00 kpa to 12000 kpa. The flow rate of hydrogen gas is 100 Nl / l of feed oil / l to l of feed oil
00Nl / feedstock l, preferably 150Nl / feedstock l
˜700 Nl / feed oil 1 range.

In the second hydrotreating zone, the hydrotreating catalyst may be any of CoMo type, NiMo type and NiW type, but a hydrotreating catalyst having enhanced aromatic nucleus hydrogenation activity is used. It

For example, a hydrotreating catalyst obtained by using a refractory inorganic oxide as a carrier and supporting a nickel-molybdenum component or a nickel-tungsten component is suitable. As the refractory inorganic oxide, silica as described above, alumina, titania, silica-alumina, alumina-titania, alumina-zirconia, silica-magnesia can be used, as the hydrogenation active component, other than the above, a noble metal component, For example, platinum, palladium, ruthenium or the like can be used.

The ratio of the amount of the catalyst filled in the second hydrotreating zone is preferably 50% to 10% of the total amount of the catalyst. By setting the catalyst amount ratio within this range, the levels of desulfurization and denitrification activities and the level of dearomaticity can be maximized.

The second hydrotreating zone is intended to remove polycyclic aromatics in order to supply a good quality FCC raw material, and has been achieved by adopting a specific reaction temperature. This reaction temperature is lower than the reaction temperature of the first hydrotreatment zone, and is 280 ° C to 380 ° C.
Is preferred. It is set so as to maximize the dearomatization in view of the relationship between the hydrogenation reaction rate of the aromatics and the equilibrium.

Turning now to the process of the present invention, FIG. 1 shows a flow chart as an example of an embodiment of the present invention. In FIG. 1, 1 and 2 are reaction towers, 3 is a heating furnace, 4 and 5 are pumps, 6 and 7 are gas-liquid separators, and 8 and 9 are strippers.

In FIG. 1, the feedstock oil is mixed with hydrogen through a line 10 and a pump 4 and introduced into a heating furnace 3,
After being heated to a predetermined temperature, it is introduced into the first hydrotreating reaction tower and subjected to hydrotreating. The mixture of treated oil and hydrogen gas is passed from the reaction tower 1 through the line 13 to the separator 6
And is separated into gas and liquid. Hydrogen sulfide and ammonia in the gas separated here are removed by stripping. On the other hand, the treated oil is introduced into the stripper 8 through the line 15, where the light components are separated through the line 17. Processed oil after stripping is line 1
It is introduced into the second hydrotreating reaction column 2 via 6 and 18.

The present invention is characterized in that the reaction temperature of the second hydrotreating reaction tower is lower than the reaction temperature of the first hydrotreating reaction tower. It is possible to take measures such as recycling to 18 and introducing into the second hydrotreating reaction tower 2, introducing low temperature gas, or lowering the temperature of the product from the first hydrotreating reaction tower 1 by heat exchange. .

A mixture of hydrogen gas and treated oil is taken out from the lower part of the reaction tower 2, separated by a gas-liquid separator 7 through a line 19, and a light component is removed from a line 22 by a stripper 9 through a line 20 and a line 21. The product is collected through.

[0030]

Next, the present invention will be described with reference to examples.

Examples 1 to 4 and Comparative Examples 1 to 3 Using vacuum gas oil as crude oil, it was subjected to a two-stage hydrotreatment according to the flow shown in FIG. Table 1 shows the properties of the raw material oil, the reaction conditions and the evaluation results. For comparison, the results of making the reaction temperatures of the first and second hydrotreatments the same are also shown.

Further, a reaction test was carried out on the fractions obtained by cutting the treated oils obtained in Examples 1 to 4 and Comparative Examples 1 and 2 at 700 ° F. or above by using a MAT apparatus of a fluid catalytic cracking apparatus. The results are shown in Table 2.

From the experimental results shown in Table 1, when the reaction temperature of the second hydrotreating reaction column was set to a low temperature, there was a remarkable effect on the dearomatization rate as compared with the same case, and the desulfurization rate and denitrification rate were high. It became clear that the rate was also good. It is also understood that when a separator is provided between the first hydrotreating reaction column and the second hydrotreating reaction column, the dearomatization rate is further improved.

From the experimental results shown in Table 2, Examples 1 to 1
4, that is, the one reacted by lowering the reaction temperature of the second hydrotreating reaction column, was found to have a high 430 ° F conversion and a high yield of gasoline with high added value.

[0035]

[Table 1]

[0036]

[Table 2]

[0037]

According to the present invention, depressurized gas oil fraction and atmospheric distillation bottom oil fraction are subjected to demetalization, decarbonization, desulfurization and denitrification in the first hydrotreatment zone at a relatively high temperature. By carrying out dearomatization in the low-temperature second hydrotreatment zone, it is possible to provide a good quality FCC raw material. This raw material is F
When used in CC, the reactivity of FCC can be further enhanced, and high conversion and light oil yield can be obtained.

[Brief description of drawings]

FIG. 1 is a flowchart showing an example of an embodiment of a hydrotreating method of the present invention.

[Explanation of symbols]

 1 First reaction tower 2 Second reaction tower 3 Heating furnace 6 Gas-liquid separator 8 Stripper

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[Procedure amendment]

[Submission date] May 29, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Title of invention

[Correction method] Added

[Correction content]

Title of the Invention Hydrotreating method for raw materials for fluid catalytic cracking

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Added

[Correction content]

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Added

[Correction content]

Thus, according to the present invention, a reduced pressure gas oil fraction, an atmospheric distillation bottom oil fraction, or a mixture thereof is used in the first hydrotreatment zone so that the pore volume of 60 Å or more is the total pore volume. 40% or more of the
In the presence of a hydrotreating catalyst having a high denitrification activity, under the hydrotreating reaction conditions, contact with hydrogen produces a first hydrotreated oil from which sulfur and nitrogen compounds have been removed, The hydrotreated oil is introduced into the second hydrotreating zone and is contacted with hydrogen at a reaction temperature lower than the reaction temperature of the first hydrotreating zone in the presence of a hydrotreating catalyst having high aromatic nucleus hydrotreating activity. Thus, there is provided a method for hydrotreating a feedstock for fluid catalytic cracking , which comprises producing a second hydrotreated oil from which a polycyclic aromatic component having two or more rings is removed. ─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] June 8, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0005

[Correction method] Change

[Correction content]

However, in the conventionally proposed hydrotreating method, it is necessary to simultaneously remove not only the metal component contained in the feed oil but also various compounds, especially polycyclic aromatic components, so that the reactivity of each compound is different. It is difficult to improve the reactivity of the FCC, since many of the remaining compounds are poisonous and cause poisoning of the catalyst.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction content]

[0006]

Under the above circumstances, the present invention provides metal components, residual carbon components, sulfur compounds, nitrogen compounds in addition to vacuum gas oil fractions and atmospheric distillation residue fractions,
It is an object to realize a hydrotreatment method capable of efficiently removing all polycyclic aromatic hydrocarbons and providing a highly reactive raw material for FCC.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

[0010] That is, in the vacuum gas oil fraction or reduced crude oil fractions or mixtures thereof first hydrotreating zone, the refractory inorganic oxide as a carrier nickel as hydrogenation-active component - molybdate component and / or The cobalt-molybdenum component is supported, and the pore volume of 60 Å or more is 4% of the total pore volume.
And 0% or more, the presence of large hydrotreating catalyst of the total pore volume factor, by contacting with hydrogen under hydrotreating reaction conditions, metal content, carbon residue, sulfur and nitrogen To produce a first hydrotreated oil from which the fraction has been removed, introduce the first hydrotreated oil into the second hydrotreated zone, and carry a hydrogenation active component on the refractory inorganic oxide. in the presence of a small yet hydrotreating catalyst pore volume rate, a temperature lower than the reaction temperature of the first hydrotreatment zone 280 ° C. ~
A hydrotreating method according to claim 1, which comprises producing a second hydrotreated oil from which two or more polycyclic aromatic components have been removed by contacting with hydrogen at a reaction temperature of 380 ° C. A separator is provided between the treatment zone and the second hydrotreating zone, and the hydrotreating method according to the item consisting of stripping hydrogen sulfide and ammonia in the circulating gas, and the first hydrotreated oil hydrogenation of the above, wherein consisting lowering the reaction temperature of the second hydrotreating zone region by merging the feedstock with or second hydrotreated oil heat exchanger to be introduced into single hydrotreating zone area fifth processing method, and the second hydrogenation catalyst amount ratio total catalyst volume of the treatment zone area
A hydrotreating method according to the above paragraph is provided which is 0% to 10%. Hereinafter, the present invention will be described in detail.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Name of item to be corrected] 0015

[Correction method] Change

[Correction content]

The reaction pressure is 2000 kpa to 20000.
kpa range, preferred reaction pressure is 3000 kp
It is in the range of a to 12000 kpa. The feedstock flow rate is
It is in the range of 0.5 V / H / V to 4.5 V / H / V, and the preferable feed oil flow rate is 0.6 V / H / V to 2.5 V / H.
The range is / V. The flow rate of hydrogen gas is 100N1 /
The raw material is in the range of 1 to 1000 N1 / feed oil 1, and the preferable hydrogen gas flow rate is in the range of 150 N1 / l to 600 N1 / l. Hydrogen sulfide, ammonia or lower hydrocarbons produced by the hydrocracking reaction is mixed in the hydrogen gas,
Although it can be introduced into the second hydrotreating zone without gas-liquid separation, ammonia sulfide and the like can be removed after gas-liquid separation. In this case, hydrotreated oils stripped from lower hydrocarbons, hydrogen sulfide, since ammonia is divided <br/>, desulfurization and denitrogenation reactions, be particularly further improve the dearomatization rate it can.

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Claims (1)

[Claims] 1. A degassed gas oil fraction, an atmospheric distillation bottom oil fraction, or a mixture thereof is demetallized in the first hydrotreatment zone.
Contact with hydrogen in the presence of a hydrotreating catalyst having high residual carbon, desulfurization / denitrification activity, and under hydrotreating reaction conditions including a reaction temperature of 280 ° C. to 450 ° C. and a reaction pressure of 2000 kpa to 20000 kpa. To produce a first hydrotreated oil from which the metal content, residual carbon content, sulfur compounds and nitrogen compounds have been removed, and introduce the hydrotreated oil into the second hydrotreatment zone for aromatic nuclear hydrogenation. In the presence of a highly active hydrotreating catalyst, the reaction temperature of the second hydrotreating zone is lower than the reaction temperature of the first hydrotreating zone and contacted with hydrogen at a reaction temperature of 280 ° C to 380 ° C. The method for hydrotreating a fluid catalytic cracking feedstock, which comprises producing a second hydrotreated oil from which aromatic components having two or more rings are removed.