JPS61130394A - Method for converting heavy oil into light oil - Google Patents

Abstract

PURPOSE:To obtain light oil efficiently without causing lowering in the activity of catalyst, by cracking a heavy hydrocarbon oil in the presence of a hydrogen- donating solvent, depositing heavy metals on a solid material to remove them, carrying out hydrogenation and fractionating reaction products. CONSTITUTION:A heavy hydrocarbon oil 5 contg. at least 10wt% asphaltene component is introduced into a first-stage reaction tower 1 and cracked in the presence of a hydrogen-donating solvent 12. The reaction mixture is then introduced into a second-stage reaction tower 2 and cracked in the presence of a solid catalyst and a porous solid material (e.g. alumina) and at the same time, at least 50wt% of heavy metals contained therein is deposited on the solid material. The reaction mixture is then introduced into a third-stage reaction tower 3 and hydrogenated in the presence of a hydrogenation catalyst and hydrogen gas 6. The resulting reaction mixture is fed to a separator 4 to recover a light oil product 11 and to recycle a fraction 10 contg. the hydrogen donating solvent to the first-stage reaction tower 1.

Description

[Detailed Description of the Invention] [Field of Ordinary Industrial Application] The present invention is a method for lightening heavy oil, particularly heavy oil containing an asphaltene content, that is, a pentane insoluble content in an LOTL amount or more, by hydrocracking. Regarding the method.

[Prior art and problems to be solved by the invention] Hitherto, it has been known to hydrocrack heavy oil and convert it into high-value products, and many methods have been implemented or Proposed.

Here, heavy oil refers to the fraction with a boiling point of 350℃ or higher, which is 50% by weight.
Examples of hydrocarbon oils containing the above include those obtained from atmospheric distillation residues obtained from crude oil, vacuum distillation residues obtained from coal, oil sands, oil shale, picumen, etc. Furthermore, the lightening mentioned here refers to the purpose of obtaining light oil containing naphtha, gasoline fraction, kerosene fraction, etc. by subjecting the above-mentioned M quality oil to fractionation accompanied by hydrogenation. be.

One of the important problems in the above-mentioned hydrocracking of heavy oil is a decrease in catalyst activity. In other words, heavy oil contains asphaltene, which also contains heavy metals such as vanadium and nickel, which significantly poisons the catalyst, which is a factor that hinders economical long-term continuous operation. It has become. In order to solve this problem, efforts have been made to improve catalysts, and many excellent catalysts have been proposed, but the state of the catalysts is still far from satisfactory.

Another important problem in hydrogen processing is the high cost of hydrogen. In the hydroprocessing of heavy oil, the heavier the feedstock oil, the greater the amount of hydrogen consumed, and the cost associated with this increases enormously.

As one method to solve this hydrogen cost problem, a hydrogenation method using a hydrogen-donating compound obtained by hydrogenating a polycyclic aromatic compound is known (for example, U.S. Pat. No. 4,430,197). It is well known that when heavy oil is hydrocracked using a hydrogen donating compound such as U 54.2
No. 94.686 and Oil & Gas Jour
nal Nov, 22.1982, p, 111-11
6).

Hydrogen donating solvent (hydr, roggn dono)
r) is a compound obtained by hydrogenating a hydrocarbon compound having a multi-I aromatic ring, such as naphthalene, anthracene, etc., and such a hydrogen donor is heated at a high temperature (for example, 38
It is well known that carbon dioxide has the property of releasing hydrogen when the temperature is heated to 0° C. or higher, and many attempts have been made to utilize this property industrially (for example, US Pat. No. 2,953,513). It is also well known that pyrolysis oil, catalytic cracking oil, and hydrocracked oil of heavy oil contain substances that have such hydrogen donating properties, and that they themselves act as effective hydrogen donors ( For example, U.S. Patent Nos. 3 and 9
7 to No. 545).

The object of the present invention is to reduce the decrease in catalyst activity, ease operating conditions, and reduce hydrogen consumption.
An object of the present invention is to provide a method for hydrogenating heavy oil containing 0% by weight or more using a hydrogen-donating solvent.

[Means for solving problems]

The object of the present invention is to provide a method for hydrocracking and lightening heavy hydrocarbon oil containing asphaltene content of LO weight % or more, which includes: (1) decomposing raw material heavy oil in the presence of a hydrogen-donating solvent; (2) the reaction product mixture of the first step is further decomposed in the presence of one or more solid substances from the group consisting of a solid catalyst and a porous solid, and is contained in the feedstock oil; (3) separating the reaction product mixture in the second step from the solid material to which the heavy metals have been attached; a third step in which the first step reaction product mixture is hydrogenated in the presence of hydrogen gas and a hydrogenation catalyst; (4) the reaction product mixture in the third step is converted into a fraction containing a hydrogen-donating solvent and other This is achieved by the method of lightening heavy oil of the present invention, which is characterized in that the hydrogen-donating agent-containing fraction is fractionated into a desired fraction, and the hydrogen-donating agent-containing fraction is recycled in one stage.

The method of the present invention utilizes the fact that hydrogen-donating compounds are contained in the hydrocracked oil of heavy oil and act as hydrogen donors themselves, and process heavy oil in three stages. This is one of its characteristics. The inventors of the present invention have clarified the following facts through experiments, that is, by decomposing heavy oil using a hydrogen-donating solvent in the first stage, and then continuing to decompose the heavy oil in the second stage. Metals such as vanadium and nickel contained in ifX oil are made in a state that is very easy to remove.
By removing metals such as vanadium and nickel in this second stage, the cracked oil entering the third stage is lightened and at the same time most of the metals are removed.
In this stage, the reduction in catalyst activity is significantly reduced and the operating conditions become significantly milder.

The method of the present invention will be explained in more detail.

An example of a flowchart for implementing the present invention is shown in FIG. 1 of the accompanying drawings.

In the K1 diagram, 1 is the first stage reaction tower, 2 is the second stage reaction tower,
3 is the third stage reaction tower, 4 is the separation device, 5 is the raw material heavy oil introduction path, 6 is the hydrogen gas introduction path, 7.8 and 9 are the first
, a stagnation channel for the reaction product mixture in the second and third reaction towers, 10 a recirculation channel for the hydrogen-donating solvent from the separation device 4 to the first reaction tower, 11 a product outlet channel from the separation device, 12
is the makeup introduction route for the hydrogen-donating solvent.

The raw material heavy oil passes through the raw material heavy oil introduction path 5 and then into the recirculation flow path 1.
1st stage reaction column 1 with recirculated hydrogen donating rd agent from 0
decomposition using a hydrogen-donating solvent. The reaction in this first reaction tower is preferably carried out in a heated oven at 380°C to 470°C. The reaction in the first reaction column is carried out in an empty column without any packing material or the like. Next, both the decomposition product from the first-stage reaction tower and the hydrogen-donating solvent that released hydrogen in the first-stage reaction tower are directly led to the second-stage reaction tower.

In the second reaction tower, a solid catalyst, a porous solid, or both of these solid substances are made to exist, and vanadium, nickel, etc., which are easily removed by decomposition in the first reaction tower, are deposited. Here, 50% by weight or more of the heavy metals contained in the raw material oil are allowed to adhere to the solid substance. The reaction in the second reaction tower is preferably carried out at a temperature of 300°C to 470°C. Next, both the decomposition product from the second stage reaction tower and the hydrogen-donating solvent that released hydrogen in the second stage reaction tower are directly led to the third stage reaction tower.

However, the solid catalyst and/or porous material present in the second stage reaction tower is not led to the third stage reaction tower.

In other words, after the reaction in the second stage reaction tower, the entire contents excluding the solid catalyst and porous solids (referred to as reaction product mixture) are
Shame on the reaction tower.

Note that in the first and second reaction towers, hydrogen is supplied using a hydrogen-donating solvent, so hydrogen gas is not necessarily required, especially high-pressure hydrogen gas, but it can be used to prevent coking or to provide hydrogen. Pressure is preferably applied to keep the solvent in the liquid phase. However, the pressure is 20 to 100 Kf/CM, which does not require high pressure like the conventional method using a catalyst.
・About 1 g is sufficient. In addition, the third stage reaction tower 3 requires high pressure hydrogen gas, and it is convenient to share this with the hydrogen pressure of jgl and the second reaction tower. It is preferable to introduce hydrogen gas into the first-stage reaction tower and conduct the reaction while maintaining the hydrogen gas pressure in the first and second reaction towers at 20 to 150, 9/era''·g.

The hydrogen-donating solvent together with the decomposition product from the second stage reaction tower 2 is led to the third reaction tower 3 via the flow path 9, where it is hydrogenated in the presence of a hydrogenation catalyst. Hydrogenation in this third stage reaction column is no different from conventional hydrogenation using a fixed bed. In the third stage reaction tower, hydrogenation is carried out at a reaction temperature of 300° C. to 400° C. and a hydrogen pressure of 20 to 150 Kq/cm”·g1 in the presence of a hydrogenation catalyst.

Since the heavy feedstock oil is lightened in the first and second stage reaction towers, the operating conditions of the third stage reaction tower can be mild, and since metals are removed in the second stage reaction tower, In addition, the decrease in the activity of the catalyst in the third stage reaction column is very slight.

Through hydrogenation in the third stage reaction tower, the hydrogen-donating slag is regenerated (hydrogenated) and becomes a substance with scale-donating properties again.
At the same time, the decomposition products are hydrorefined to remove impurities such as sulfur and nitrogen, resulting in products.

The reaction product mixture in the third reaction column, i.e. the entire contents of the reaction column except the solid catalyst, passes through stream 1R1r9 to separator 4.
It is sent to the
Through the product stream Mll, desired products such as gas, Ganli/su7jo fraction, kerosene fraction, light oil fraction, heavy oil fraction, etc. are recovered, and the hydrogen-donating solvent passes through the circulation path 10 and returns to the first reaction. Used for circulation in the tower. At this time, it is preferable to perform rounding and make-up 12 in which the hydrogen-donating solvent is lost.

One of the preferred examples of the hydrogen-donating solvent used in the present invention is a hydride of polycyclic aromatic hydrocarbon. Examples of the polycyclic aromatic hydrocarbon include 2 to 6 rings, preferably 2 to 6 rings.
Examples include 4-ring aromatic hydrocarbons and derivatives thereof. These aromatic hydrocarbons can be used alone or in combination of two or more.

Specific examples of the aromatic hydrocarbons include lotus 7-talene, anthracene, 7-enanthrene, pyrene, na7-tase/, chrysene, benzopyrene, perylene, picene, etc., or derivatives thereof.

Hydrogenated hydrocarbon oils having a boiling point of 150° C. to 500° C. and a polycyclic aromatic hydrocarbon content of 20 wtTo or more are also suitable for use as the hydrogen-donating solvent of the present invention. A specific example of the hydrocarbon oil is a catalytic cracker (FCC).
), various products obtained from petroleum such as cycle oil, bottom oil of catalytic reforming equipment, pyrolysis oil of naphtha, or tar oil,
Various products obtained from coal such as anthracene oil, creosote oil, coal liquefied oil, etc. can be opened.

In the present invention, an oil selected from FCC cycle oil and naphtha pyrolysis oil containing 7-talene, anth-2 cene, etc. as main components is preferably used.

In the present invention, the polycyclic aromatic hydrocarbon and hydrocarbon oil may be hydrogenated in advance and charged into the present apparatus,
Since hydrogen gas coexists in this device, it is hydrogenated in this device and becomes a hydrogen-donating pillar core agent, so it is not necessarily necessary to hydrogenate it in advance.

The raw material oil used in the method of the present invention has an asphaltene content (pentane insoluble content) of 1.0% or more, preferably 5 to 30%.
These include heavy oil, atmospheric residual oil, vacuum residual oil, oil obtained from coal, oil sand, oil shale, bitumen, etc., in which the fraction with a boiling point of 350° C. or higher accounts for 50° C. or more.

The purpose of the solid catalyst and/or porous solid used in the 1R reaction tower of the present invention is not only to contribute to the decomposition of heavy oil, but also to collect and attach metals that are easily removed by decomposition. As for the properties of the solid catalyst and porous solid, it is preferable that the metal adhesion ability is high.

There are no particular restrictions on the solid catalyst, and it can be used in other heavy oil processing processes,
For example, a catalyst used for hydrocracking, hydrodemetalization, hydrodesulfurization, etc. of heavy oil or a used catalyst can be used.

Further, a small amount of new catalyst can be mixed with these, or a catalyst with relatively low activity can be used in place of the above-mentioned waste catalyst. Solid catalysts include inorganic substances such as alumina, silica, silica-alumina, alumina-boria, silica-alumina-magnesia, silica-alumina-titania, Group 1 substances such as nickel and cobalt, and Group VIB substances such as molybdenum and tungsten. An example is an M1 medium carrying a metal oxide X-ray sulfide. Examples of porous solids include inexpensive ones such as alumina, silica-alumina, ceramics, carbonaceous materials, and clay.

The catalyst used in the third stage reaction column of the present invention is not limited to this method, and any catalyst commonly used in hydrotreating can be used for each purpose. The choice can be made depending on the composition and properties of the raw material oil and the composition and properties of the required product.

Catalysts used in the third stage reaction include alumina, silica,
Group 1 metal oxides or sulfides such as nickel and cobalt and Group ViB metals such as molybdenum and tungsten are added to inorganic supports such as silica-alumina, alumina-boria, silica-alumina-magnesia, and silica-alumina-titania. A supported one is preferably used. As for the properties and shape of the catalyst, any of those conventionally used can be used.

In the present invention, any of a fixed bed type, a moving bed type, and a fluidized bed type may be used as the second and third stage reaction tower types, but it is particularly preferable to use a fixed bed type.

The operating conditions of the present invention are charging of raw material heavy oil (LH5V)
(Amount of feedstock oil charged / Amount of hydrogenation catalyst) (hr-') is 0
．． 1-2.0, hydrogen gas supply i (Nm”/kl feedstock oil) from 200 to 1500, circulation number of hydrogen-donating solvent −j
! [(kl/kl raw material oil) from 0.1 to zo, preferably from 0.1 to 1. It is preferable to carry out within the range of o.

〔Example〕

EXAMPLE An experiment was carried out for the purpose of reducing the weight of vacuum residue oil by using the method of the present invention. The fourth stage reaction tower was an empty tower, and the second stage reaction tower was equipped with a direct desulfurization catalyst for atmospheric residual oil, which had already been used industrially for about 1,000 hours, as a downward flow fixed bed. A silica-alumina carrier (pore volume 0.65 / g 1 surface area 210 m'' 7 g, average pore radius TOA) was used as a catalyst in the third stage reaction tower, cobalt (40 wt%), molybdenum (t
A 720-inch extruded product carrying tswt was filled and used. The reactor is the first stage, 1iE2
Each of the stage and third stage reaction towers had an inner diameter of 40 x φ and a length of 1,300 m, and each of the above-mentioned catalysts had the same total length as each of the second and third stage reaction towers. I tried to make it OO. The raw material oil and hydrogen gas shown in Table 4 were heated with a heater and then introduced into the reaction tower in a downward flow. As the hydrogen-donating solvent, naphtha thermal cracker bottom oil, called thermal cracking oil, whose properties are shown in Table 4, was used, and the make-up amount was 25 wtq6 relative to the feedstock oil. The gas and liquid coming out of the third stage reaction tower are separated in a gas-liquid separator, and then the liquid is passed through a distillation tower at 200°C to 25°C.
The 0°C fraction was collected and recycled as a hydrogen-donating solvent. The amount of solvent used was L5 times that of the raw material oil. After the hydrogen gas is separated in the gas-liquid separator mentioned above, a portion of it is recycled and used.
After mixing with make-up hydrogen, it was charged into the first stage reaction tower together with the raw material oil and circulating bath agent through a heater. The operation time was 2.3ooFRf continuously. The properties of the raw material oil and the properties of the product were shown to Company 1. The operating conditions were as shown in Table 2. It is also shown in Table 3 of material balance 1 at Honsho Shun. In addition, the temporal change in the decomposition rate is shown in □2.
Shown in the figure. Here, the decomposition rate is α-b
(wt%) b: Defined as the fraction (wt%) of fractions of 565°C or higher in the product. In order to check the metal removal rate in the first stage reaction tower, a liquid sample was taken at the outlet of the Ki second stage reaction tower and the amount of metal was measured. The results are shown in Table 5.

Comparative Example A hydrocracking experiment was conducted using a conventional fixed bed reactor using the same raw materials, the same equipment, and the same catalyst as in the example. However, in both the second and third stage reaction towers of No. 11, the catalyst packed in the third stage reaction tower of the example was used. A conventional hydrocracking method using hydrogen and a catalyst was used instead of adding a hydrogen-donating solvent to the system or circulating the hydrogen-donating solvent within the system. The operation was continued for 2300 hours and compared with the example. The operating time is shown in Table 2, and the product properties and material balance are shown in Tables 1 and 3, respectively. Figure 2 also shows the change in decomposition rate over time.

Note that the feedstock oil and hydrogen gas were charged in a downward flow as in the example.

Furthermore, Table 5 shows the decomposition rate and metal removal rate at the outlet of the g2-stage reaction tower.

Table 2 Operating conditions Table 3 Material balance and hydrogen consumption Table 4 Specific gravity of pyrolysis oil Properties and specific gravity of pyrolysis oil LO28 Viscosity 637.8℃ 420 @9 & 9℃ L33 Structural analysis y)2 al CH(:', p(nzu7(n)40 Fractional distillation properties ('C) IBP 192 EP 390 Table 5 Decomposition rate and metal removal rate in the second stage reaction tower Operating time 1800 hours [Invention [Effects] From the results of Examples and Comparative Examples, it is clear that the present invention has the following effects.

As shown in Figure 2, there is almost no decrease in the decomposition rate in the Examples, but there is a significant decrease in the decomposition rate in the Comparative Examples, which may be due to a decrease in the activity of the catalyst. is clear. The reason is (1)
Activity reduction due to metal (2) Activity reduction due to carbon from asphaltene. The first stage reaction tower of the example is a decomposition zone using a hydrogen-donating solvent, and decomposition proceeds even without a catalyst.

As shown in Table 5, in the second stage reaction tower of the example filled with a catalyst that has already been used industrially, lightening was achieved reaching a decomposition rate of 78%, and 70 to 85% of metals were removed. ing. Therefore, the adhesion of metals such as vanadium and nickel onto the catalyst in the third stage reaction tower is extremely small, and the decrease in catalyst activity caused by this is slight. The temperature of the third stage reaction tower was 340°C in the example and 40°C in the comparative example.
It is lower than that at 0°C, and therefore the decrease in activity due to carbonaceous matter from 7-sphaltene is also small. For these reasons,
In the Examples, there is almost no decrease in the decomposition rate due to operating time, but in the Comparative Examples, the decomposition rate decreases significantly due to a decrease in the activity of the catalyst.

(2) High decomposition rate.

The method of the present invention allows C111 to pass through a larger amount of oil than the comparative example.
, 2 Table 11Cu-CLH5V=CL3, ratio! 1e example t
io, 2), the decomposition rate is large (5th
Table and Figure 2). This is the N1 stage reaction column and the second
This is because significant lightening occurs in the plate reaction tower, indicating that the lightening effect of the ice-water donating solvent is significant.

(3) Can be carried out at low reaction pressure.

The weight shown in Table 2 is 70 Kg/cm in the example.
” ・Executed at 170 kg/cm (comparative example)
”・g).

Fundamentally, when a hydrogen-donating solvent is used, hydrogen transfer occurs in the liquid phase, so the pressure that keeps the hydrogen-donating solvent in the liquid phase is sufficient; High pressure is not required. In addition, in the third stage reaction column of the method of the present invention, as shown in Table 5, the K-already lightened oil is hydrotreated and the hydrogen-donating solvent is hydrogenated. For these hydrogenation reactions, a very high pressure is not required, and the pressure as in the example is sufficient.

(4) Low hydrogen consumption.

As shown in Table 3, despite the high decomposition rate, the amount of hydrogen consumed may be small. The reason for this is the first and second stage.
In the stage reaction tower, hydrogen transfer is carried out in the liquid phase, so hydrogen is efficiently transferred, and despite the high decomposition rate, the amount of hydrogen consumed is small. Since the hydrogenation of oil is carried out, the reaction takes place at a relatively low temperature, and the amount of hydrogen consumed is small. Furthermore, hydrogenation of the hydrogen-donating bath agent is carried out efficiently, and there is little wasteful consumption of hydrogen. Therefore, even if the total amount of hydrogen consumed in the first, second and third reaction columns is small, effective lightening can be achieved.

From the above description, the features and advantages of the method of the present invention will be apparent and it will be apparent that the method is a significant improvement over conventional methods.

[Brief explanation of drawings]

FIG. 1 is a block diagram for explaining the present invention in detail, and FIG. 2 is a graph showing temporal changes in decomposition rates in Examples and Comparative Examples.

Claims (1)

[Claims] 1. A method for lightening heavy hydrocarbon oil containing 1.0% by weight or more of asphaltene by hydrogen cracking: (1) raw material heavy oil in the presence of a hydrogen-donating solvent; (2) further decomposing the reaction product mixture of the first stage in the presence of one or more solid substances from the group consisting of a solid catalyst and a porous solid; a second step in which 50% by weight or more of the heavy metals contained therein are attached to the solid material; and (3) the reaction product mixture in the second step is separated from the solid material to which the heavy metals are attached; a third step in which the second step reaction product mixture is hydrogenated in the presence of hydrogen gas and a hydrogenation catalyst; A method for lightening heavy oil, which comprises fractionating it into other desired fractions and recycling the hydrogen-donating solvent-containing fraction to the first stage. 2. The method according to claim 1, wherein the first step reaction is carried out in the presence of hydrogen gas. 3. The method according to claim 1, wherein the second stage reaction is carried out in the presence of hydrogen gas. 4. In the first and second stages, at least some hydrogen is released from the hydrogen-donating solvent, and in the third stage, the hydrogen-donating solvent that released the hydrogen is hydrogenated to produce a hydrogen-donating solvent. The method according to claim 1. 5. The temperature of the first stage is 380°C to 470°C, the temperature of the second stage is 300°C to 470°C, and the temperature of the third stage is 300°C.
The method according to claim 1, wherein the temperature is maintained at ~400°C. 6. The method according to claim 1, wherein the pressure in the first, second, and third stages is maintained at 20 to 150 Kg/cm^2.g using hydrogen gas. 7. The method according to claim 1, wherein the hydrogen-donating solvent is a hydride of a polycyclic aromatic hydrocarbon. 8. The method according to claim 1, wherein the hydrogen-donating solvent is a hydride of a hydrocarbon oil having a boiling point of 150°C to 500°C and a polycyclic aromatic hydrocarbon content of 20 vot% or more. 9. The amount of circulating liquid of the hydrogen-donating solvent-containing fraction is 0.1 to 2.
0 (kl/kl raw material oil). 10. The method according to claim 1, wherein the hydrogen-donating solvent is added from outside the system. 11. The method according to claim 1, wherein the solid material in the second stage and the hydrogenation catalyst in the third stage are used as a fixed bed.