JPH06179880A - Method of hydrotreatment of heavy oil - Google Patents

Abstract

PURPOSE:To provide a method of hydrotreatment of heavy oil which is suitable for eliminating metals contained in the heavy oil. CONSTITUTION:The hydrotreatment method contains the hydrodemetallization step wherein a slurry made by mixing a heavy oil contg. at least 10ppm heavy metals, Ni and V, with a catalyst powder having a mean particle size of 0.1-100mum and contg. fine hardly sulfurizable ferromagnetic particles dispersed therein is treated at 300-500 deg.C under 10-250kg/cm<2> pressure in the presence of hydrogen and the catalyst separation step wherein the catalyst powder is separated from the treated slurry with a magnetic separator.

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 heavy oil, and particularly to a heavy metal containing at least nickel and vanadium in a total amount of at least 10 ppm among heavy metals such as nickel, vanadium, iron and copper. The present invention relates to a method for hydrotreating heavy oil, which comprises hydrodemetallizing an oil in the presence of a powder catalyst, and then efficiently separating the hydrodemetallized oil and the powder catalyst by using a magnetic separator.

[0002]

BACKGROUND ART Heavy oil containing distillation residues obtained by atmospheric distillation or vacuum distillation contains a large amount of metals such as nickel, vanadium, iron, copper and sodium in addition to nitrogen and sulfur. Has been. Therefore, when such a heavy oil is subjected to hydrorefining to obtain a fuel oil, not only these metals contained in the heavy oil are deposited on the hydrotreating catalyst to lower the catalytic activity. However, it also promotes the formation of coke and causes a drift of the feedstock in the catalyst bed. The hydrorefining referred to here is a method in which the feedstock oil is catalytically treated under pressurized hydrogen to remove the sulfur and nitrogen components in the feedstock oil as hydrogen sulfide and ammonia.

Usually, in order to reduce the influence of such polluted metals, the metal removal selectivity is high in the preceding stage of the hydrodesulfurization catalyst,
It is filled with a hydrodemetallization catalyst having a large metal holding capacity. Although the life of the hydrodesulfurization catalyst is extended by this, not all the metal in the feed oil can be captured by the hydrodemetalization catalyst, so the metal slipping the hydrodemetalization catalyst is deposited on the hydrodesulfurization catalyst, The activity of the hydrodesulfurization catalyst is gradually reduced. Further, when the heavy oil containing a high concentration of metals is hydrotreated, the metal holding capacity of the hydrodemetallizing catalyst will be exceeded in a short period of time, so it is necessary to frequently replace the catalyst.

As a method of removing pollutant metals from heavy oil, a method of carrying out a hydrodemetallization reaction in a slurry bed using a powder catalyst and continuously withdrawing a used catalyst from the apparatus can be considered. However, in this case, it is difficult to separate the produced oil and the catalyst.

Japanese Patent Publication No. 61-44916 has reported the use of a high gradient magnetic separator as a method for separating the catalyst from the product oil reacted in such a slurry bed. In this case, the catalyst used is Ni, C having hydrogenation activity on a porous carrier such as alumina.
It is a powder of a so-called hydrotreating catalyst supporting sulfides such as o, Mo and W, or a catalyst in which a ferromagnetic powder substance such as magnetite is physically mixed with the powder catalyst. The former catalyst has a high demetallizing activity because it is a hydrotreating catalyst, but this catalyst has a paramagnetic property of 350 to 50.
Under the reaction temperature condition of 0 ° C., the magnetism is extremely weak, and it is difficult to completely separate the catalyst even by using a high gradient magnetic separator. Therefore, in order to completely separate the catalyst from the produced oil, the temperature of the magnetic separation must be lowered, but the temperature must be raised again in the subsequent hydrodesulfurization, which is disadvantageous from an economical point of view. In addition, if it is a ferromagnetic material such as magnetite, the catalyst can be easily separated from the produced oil even under reaction temperature conditions, but since such a material has a very small surface area, it has almost no hydrodemetallizing activity. Not not.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a heavy oil hydrotreating method suitable for removing metals contained in the heavy oil.

[0007]

The inventors of the present invention have conducted extensive studies to solve the above-mentioned problems, and as a result, by using a catalyst containing a specific component, the efficiency and selectivity of magnetic separation are improved, and an equilibrium catalyst is obtained. The inventors have found that the activity and selectivity of can be maintained at a high level, and have completed the present invention.

That is, according to the present invention, a powder catalyst containing a heavy oil containing nickel and vanadium in a total amount of 10 ppm or more as a heavy metal content and having an average particle size of 0.1 to 200 μm dispersed and containing non-sulfurizable ferromagnetic fine particles is dispersed. In the presence of hydrogen, the temperature of the slurry is 300 to 500 ° C., and the pressure is 10 to 250.
Hydrogenation of heavy oil comprising a hydrodemetallization treatment step of treating with kg / cm ² and a catalyst separation step of separating the powdered catalyst from the demetallized slurry with a magnetic separator. Provide a processing method.

The present invention also provides a heavy oil containing nickel and vanadium as a heavy metal component in a total amount of 10 ppm or more,
In the presence of hydrogen, a slurry mixed with a powder catalyst having an average particle diameter of 0.1 to 200 μm and containing non-sulfurizable ferromagnetic fine particles dispersed therein is heated at a temperature of 300 to 500 ° C. and a pressure of 10 to 250 kg.
/ Cm ² , a hydrodemetallization treatment step, a catalyst separation step of separating the powder catalyst from the demetallized slurry using a magnetic separator, and a powder catalyst obtained from the separation step are separated. And a hydrotreating step of hydrotreating the treated oil.

The present invention will be described in more detail below. The heavy oil used in the present invention means a fraction having a boiling point of 565 ° C or higher.
Contains 0 vol% or more and has a density at 15 ° C of 0.89 g /
A hydrocarbon oil containing ³ cm ³ or more, containing heavy metals such as iron, nickel, vanadium and copper together with sulfur and nitrogen, and carbonizing at least 10 ppm or more of nickel and vanadium in total of these heavy metals. It is hydrogen oil. Examples of such oils include atmospheric distillation residual oil, vacuum distillation residual oil, shale oil, tar sand bitumen, orinocotal, and coal liquefied oil. Further, a mixture of a relatively light oil such as straight-run light oil or vacuum light oil and the above heavy oil is also included in the heavy oil in the present invention. In the present invention, atmospheric distillation residual oil and vacuum distillation residual oil are particularly preferably used. Further, in order to increase the economic advantage of the treatment method of the present invention, the total amount of nickel and vanadium contained in the heavy oil is preferably 50 ppm or more, and 100
More than ppm is more preferable.

The catalyst used in the present invention has an average particle size of 0.1.
The powder catalyst has a particle diameter of ˜200 μm, preferably 1 μm to 100 μm, and contains the non-sulfurizable ferromagnetic substance particles in the powder catalyst. The smaller the average particle size of the powder catalyst is, the higher the hydrodemetallizing activity is, but if the average particle size is less than 0.1 μm, it becomes difficult to separate the catalyst from the produced oil even by using a magnetic separator. Further, if the average particle size exceeds 200 μm, the hydrodemetallizing activity decreases.

In the present invention, the powder catalyst preferably comprises a porous carrier, a hydrogenation active metal, and a refractory sulfur compound. The porous carrier has a surface area of 10 m ² / g or more, preferably 50 m ² / g or more, more preferably 200 m ² / g or more and a pore volume of 0.1 cc / g or more, preferably 0.5 cc / g or more. Examples of such heat-resistant carriers include porous inorganic oxides and carbonaceous carriers. Examples of porous inorganic oxides include alumina, silica, silica-alumina, silica-magnesia, alumina-magnesia, alumina-boria, silica-titania, silica-zirconia, synthetic zeolites and other natural compounds such as sepiolite and natural zeolites. There are things,
Alumina is particularly preferably used. Examples of the carbonaceous carrier include activated carbon and carbon black.

The hydrogenation active metal supported on the porous carrier is at least one selected from W, V, Mo, Ni, Co and Fe. Ni-Mo, Co-
A combination of Mo and Ni-Co-Mo is particularly preferable. The hydrogenation active metal is preferably supported on the porous inorganic oxide as an oxide, a sulfide or a precursor of an oxide or a sulfide. The concentration of the hydrogenation active metal in the powder catalyst is preferably 5 to 40 wt% as a metal oxide, and 10 to 30
wt% is more preferable.

Spinel-type ferrite, a non-sulfurizable ferromagnetic substance contained in the powder catalyst used in the present invention,
Examples include hexagonal alkaline earth ferrite, various ferrites such as yttrium and rare earth ferrites, and the like. However, since it is necessary to be ferromagnetic at the temperature at which magnetic separation is performed, a substance having a Curie point of changing from ferromagnetism to paramagnetism of 300 ° C. or higher, preferably 500 ° C. or higher is used.

Further, it is necessary that the ferromagnetic material is hardly sulfurized under the hydrodemetallizing condition. The refractory sulphidity here means, for example, a ferromagnetic material at 400 ° C. in a hydrogen sulfide / hydrogen mixed gas (5 vol% H ₂ S) at 1 atm,
It means that the reduction rate of the saturation magnetization of the ferromagnetic material after the treatment for 1 hour is 50% or less, preferably 30% or less.

In the present invention, Ba-based ferrite, Z
N-type ferrite, Mn-type ferrite, and Zn-Mn-type ferrite are preferably used. The average particle size of the ferromagnetic material used in the present invention is preferably in the range of 0.05 to 50 μm, more preferably 0.1 to 25 μm. Further, it is preferably 1/4 or less of the average particle diameter of the powder catalyst. The ferromagnetic material and the powdered catalyst are not used as a physical mixture of separate particles, but are used in the integrated state in which the ferromagnetic material is dispersed in the powdered catalyst. The content ratio of the ferromagnetic material in the powder catalyst is 0.0
The range of 1 to 50 wt% is preferable, and 0.05 to 10 wt
The range of% is more preferable.

The method of dispersing the ferromagnetic substance in the powder catalyst used in the present invention is not particularly limited, but the following method is preferably adopted. For example, a method of supporting a ferromagnetic substance or a precursor of a ferromagnetic substance on a porous inorganic oxide carrier or a carbonaceous carrier, or fine particles of a ferromagnetic substance on a gel metal hydroxide. Disperse,
The method of drying and baking it is mentioned. As a method of molding the catalyst into powder, a method of pulverizing a dried or calcined catalyst by a wet method or a dry method, or a method of spray-drying a gel or sol metal hydroxide is preferably used.

In the hydrodemetallizing treatment step in the present invention, at least 40 wt%, preferably 60 wt% or more of heavy metals such as nickel and vanadium contained in the feed oil are deposited on the powder catalyst. The conditions of this hydrodemetallizing treatment are very wide, but the reaction temperature is 300
It is necessary to be in the range of to 500 ° C, preferably 350 to 450 ° C. When the reaction temperature is lower than 300 ° C., the reaction rate of hydrodemetallization is slow and a sufficient demetallization rate cannot be obtained. The reaction temperature is 500 ° C
If it exceeds the range, a large amount of sludge is generated due to thermal decomposition, which is not preferable. Regarding other conditions, the hydrogen partial pressure is generally 10 to 250 kg / cm ² , preferably 50 to 15
0 kg / cm ² , hydrogen / feed oil ratio 100-2000N
1 / Nl, the residence time of the oil in the apparatus is 10 to 200 minutes, preferably 20 to 100 minutes. The reactor type is preferably a tubular type or an upflow ebullated bed type.

The concentration of the powder catalyst in the slurry consisting of the feed oil and the powder catalyst supplied to the hydrodemetallizing process is preferably 0.01 to 300 g / l, and 0.1 to 1 is preferable.
The range of 00 g / l is more preferable.

In this hydrodemetallizing process, the reaction conditions are set so that the demetalization rate of the total amount of nickel and vanadium contained in the feed oil is 40 wt% or more, preferably 60 wt% or more.

In the heavy oil hydrotreating method of the present invention, the slurry that has undergone the hydrodemetallizing step is sent to the next catalyst separating step, where the magnetic separator separates the hydrodemetallizing oil and the powder catalyst. And separated.

The magnetic separator referred to herein is such that a ferromagnetic packing is placed in a uniform high magnetic field space, a magnetic field gradient of at least 200 gauss / cm or more is generated around the packing, and the packing surface is formed. A magnetic separator designed to magnetize ferromagnetic or paramagnetic microparticles and separate them from oil, preferably with a high gradient having a high magnetic field gradient of 100 × 10 ^{3 to} 20000 × 10 ³ gauss / cm. It is a magnetic separator. As the high gradient magnetic separator, there are a high magnet type that generates a uniform high magnetic field by an exciting coil and a permanent magnet type that generates a uniform high magnetic field by a permanent magnet.

The ferromagnetic filler is usually 1 to 1
Aggregates of ferromagnetic wires, such as steel wool or steel net with a diameter of 000 μm, or expanded metal or steel beads are used. Expanded metal or steel beads are preferably used.

The method of separating the powdered catalyst on which heavy metals such as nickel and vanadium are deposited from the hydrodemetallized oil by the magnetic separator is to introduce the demetalized oil into the magnetic field space of the magnetic separator and This is done by magnetizing the powder catalyst on the ferromagnetic packing placed in the.

As the process variables when operating the magnetic separator, there are usually magnetic field strength, magnetic field gradient, linear velocity, particle concentration and treatment temperature, which are optimal depending on the type, size and concentration of the powdered catalyst to be magnetized. Conditions are selected.

The magnetic field strength is the strength of the magnetic field in the space where the packing is placed, and is at least 200 gausses, usually 500-25000 gausses, preferably 1000-20 gausses.
It is in the range of 000 gauss.

The magnetic field gradient is the amount of change in the magnetic field strength generated around the packing material depending on the distance and can be changed by changing the magnetic field strength or the kind and diameter of the packing material.
At least 200 gauss / cm or more, usually 100 × 10
^{3 to} 25,000 × 10 ³ gauss / cm, preferably 200
A range of 0 × 10 ^{3 to} 20000 × 10 ³ gauss / cm is used.

The particle concentration means the concentration of the powder catalyst dispersed in the hydrodemetallized oil and to be subjected to magnetic separation,
It is operated within the above range.

The treatment temperature refers to the temperature of the hydrodemetallizing oil when it is introduced into the magnetic separation, and is not higher than the reaction temperature of the hydrodemetallizing and is usually room temperature to 500 ° C., preferably 300.
To 500 ° C, more preferably 350 to 450 ° C. The treatment temperature is preferably not higher than the Curie temperature of the ferromagnetic substance particles contained in the powder catalyst.

The linear velocity is the linear velocity of oil when passing through a magnetic field, and is usually in the range of 0.1 to 50 cm / sec, preferably 0.2 to 20 cm / sec. The smaller the magnetism of the powder catalyst to be separated and the smaller the particle size, the smaller the linear velocity needs to be.

In the present invention, the powdered catalyst magnetized in the ferromagnetic packing in the magnetic separator can be washed away by lowering the magnetic field strength and flowing oil. As the cleaning oil at this time, raw material heavy oil put into the hydrotreating step, hydrodemetallized oil demetalized in the hydrotreating step, or product heavy oil obtained by further hydrotreating the demetallized oil, etc. Can be used. The powder catalyst washed away from the magnetic separator may be returned to the hydrotreating process and reused in its entirety, or part of it may be dropped into heavy fuel oil and the rest may be reused, or it may be dropped into full product heavy oil. I don't care.

The hydrodemetallized oil from which the powder catalyst has been removed in the above catalyst separation step can be further subjected to fixed bed hydrotreatment. The fixed bed hydrotreatment is a method in which a feedstock oil and hydrogen are reacted at high temperature and high pressure in the presence of a catalyst to carry out decomposition, desulfurization, denitrification, and demetallization reaction to convert into an oil effective as a product.

As the catalyst used in the fixed bed hydrotreating treatment, cobalt, nickel, molybdenum, a porous carrier such as alumina, silica-alumina, or alumina-boria is used.
A catalyst supporting a metal hydride component composed of a metal or metal compound of Group VI and / or Group VIII of the periodic table such as tungsten and platinum is used.

Conditions in the fixed bed hydrotreating process are as follows: reaction temperature 300 to 480 ° C., reaction pressure 50 to 20.
0 kg / cm ² (gauge), preferably 75 to 150 k
g / cm ² (gauge), liquid space velocity 0.1 to 10 h
r ^-1 , preferably 0.2 to 4 hr ^-1 , and a hydrogen / oil ratio of 1
The value of each region of 00 to 2000 Nl / l is adopted.

[0035]

EXAMPLES Next, examples of the present invention will be described, but the present invention is not limited thereto.

Example 1 680 g of sodium aluminate and 50% gluconic acid aqueous solution 2
0 cc was dissolved in 5 liters of pure water and heated to 50 ° C. Separately, 725 g of aluminum sulfate was dissolved in 5 liters of pure water and heated to 50 ° C. An aluminum sulfate solution was added to the sodium aluminate solution with vigorous stirring to form an alumina hydrogel. The pH at this time was 9.5. The hydrogel was aged for 1 hour, then filtered and washed to obtain a pseudo-boehmite cake. To this, 50 g of Mn.Zn-based ferrite (average particle size 1.7
5 μm, saturation magnetization 59.2 emu / g) were kneaded, and then pure water was added to adjust the viscosity, followed by spray drying with hot air at 250 ° C. This was further air-baked at 500 ° C. for 1 hour. The obtained powder had an average particle size of 55 μm and a surface area of 243 m ² / g. The composition is 95 wt% γ-alumina and 5 wt% ferrite.

Cobalt and molybdenum were supported on this powder by a usual method. The supported amount is 5 wt% CoO, MoO ₃
It is 15 wt%.

Using this powder catalyst, a Middle East vacuum residue was hydrotreated. However, before carrying out the reaction, the catalyst was pre-sulfided at 400 ° C. for 1 hour in a 5% hydrogen sulfide / hydrogen stream. Table 1 shows the properties of the raw material oil used.

Table 1 was added to the stirring type stainless steel autoclave.
1 liter of the raw material oil described in 1 above and 50 g of the above powder catalyst were added, and the reaction was performed under the following conditions.

Hydrogen partial pressure: 100 kgf / cm ² Reaction temperature: 400 ° C. Reaction time: 1 hour

After the reaction was completed, the produced oil was treated under the following conditions using an electromagnet type high gradient magnetic separator. Magnetic field strength: 20 kilogauss Linear velocity: 3.0 cm / sec Temperature: 150 ° C Filling material: Steel wool

The recovery rate of the powder catalyst by this treatment is 100.
It was wt%. Table 1 shows the properties of the treated oil after removing the powder catalyst. 1

[0043]

[Table 1]

Further, using each oil shown in Table 1,
Then, fixed bed hydrotreatment was performed. The catalyst is alumina
CoO on the body 3wt%, MoO₃13wt% supported catalyst
And a 1/32 inch cylinder type extruded product
Is. The reaction conditions are as follows.

Hydrogen partial pressure: 100 kgf / cm ² Reaction temperature: 400 ° C. LHSV: 0.3 hr ^-1 Table 2 shows the analysis results of the produced oil 50 hours after the start of the reaction.

[0046]

[Table 2]

Comparative Example 1 γ-alumina powder was prepared in the same manner as in Example 1. However, ferrite was not included. The obtained powder has an average particle size of 55 μm and a surface area of 255 m ² /
It was g. This powder was coated with Co in the same manner as in Example 1.
O5 wt% and MoO ₃ 15 wt% were supported.

After presulfiding the catalyst, the vacuum residual oil shown in Table 1 was hydrotreated in the same manner as in Example 1.
After the reaction was completed, the produced oil was treated with an electromagnet type high gradient magnetic separator under the same conditions as in Example 1. The recovery rate of the powder catalyst by this treatment was 34.7 wt%. The properties of this treated oil are shown in Table 3.

[0049]

[Table 3]

This treated oil was subjected to fixed bed hydrotreatment in the same manner as in Example 1. However, since the treated oil contained a large amount of unrecovered powder catalyst, the catalyst bed was blocked immediately after the start of the reaction and the reaction could not be continued.

[0051]

The heavy oil hydrotreating method of the present invention enables efficient removal of metals contained in the heavy oil.

Claims (2)

[Claims] 1. A slurry in which a heavy oil containing nickel and vanadium in a total amount of 10 ppm or more as a heavy metal component is mixed with a powder catalyst containing an average particle diameter of 0.1 to 200 μm and dispersible ferromagnetic fine particles dispersed therein. In the presence of hydrogen at a temperature of 300 to 500 ° C. and a pressure of 10 to 250 kg / cm ² , and a catalyst separation for separating the powdered catalyst from the demetalized slurry by using a magnetic separator. A method for hydrotreating heavy oil, comprising the steps of: 2. A slurry obtained by mixing a heavy oil containing nickel and vanadium as a heavy metal component in a total amount of 10 ppm or more with a powder catalyst having an average particle diameter of 0.1 to 200 μm and containing hard-to-sulfide ferromagnetic fine particles dispersed therein. In the presence of hydrogen at a temperature of 300 to 500 ° C. and a pressure of 10 to 250 kg / cm ² , and a catalyst separation for separating the powdered catalyst from the demetalized slurry by using a magnetic separator. A heavy oil hydrotreating method comprising: a step; and a hydrotreating step of hydrotreating the treated oil from which the powder catalyst obtained from the separating step is separated.