JP4523458B2 - Hydrocracking method of heavy petroleum oil - Google Patents

Description

  TECHNICAL FIELD The present invention belongs to a technical field related to a hydrocracking method for petroleum heavy oil, and particularly relates to a hydrocracking method for petroleum heavy oil containing a heavy metal component, and in particular, atmospheric distillation. The present invention belongs to a technical field relating to a method of hydrogenating petroleum heavy oil containing heavy metal components such as residual oil and vacuum distillation residual oil in the presence of a catalyst to obtain a highly lightened product.

  Heavy oil cracking technology that produces a shortage of light products from surplus heavy oil is attracting attention against the background of the rapid change in the demand structure where heavy crude oil and lighter demand are progressing simultaneously. The importance of oil reserves is increasing due to the unavoidable decline in oil reserves.

  So far, many methods have been proposed for thermal cracking and hydrocracking of heavy oils, but these methods have some problems for lightening heavy oils such as vacuum residue oils. Has a point.

  That is, these types of heavy oils tend to contain a fairly large amount of nitrogen and sulfur compounds, and in addition, when heavy oil decomposition is carried out in the presence of a catalyst, a large amount that tends to be extremely harmful. Contains organometallic impurities. As such organometallic impurities (metal impurities), most of them contain nickel (Ni) and vanadium (V), but many contain other metals. These metal impurities are chemically bonded to relatively high molecular weight organic compounds such as asphaltenes in heavy oil, and their presence has a considerable catalytic activity for the decomposition and removal of nitrogen, sulfur and oxygen containing compounds. Be inhibited.

  A so-called coker method, which is a thermal decomposition method, is known as a method for treating residual oil under reduced pressure and the like without using a catalyst. This method is in addition to the problem of treating coke produced as a by-product in large quantities. In addition, due to an increase in the amount of gas produced by over-cracking, the yield of distillate obtained is inevitably reduced, and there are disadvantages that the aromatic content and olefin component are large and the quality is poor.

  In the fixed-bed hydrocracking method in which a granular catalyst is packed in the reactor, when lightening is carried out to a high degree, as described above, it is affected by heavy metals such as asphaltene, V, Ni, etc. The resulting coke and heavy metal gradually deposit on the catalyst layer, resulting in a decrease in catalyst activity and clogging of the catalyst layer, and there is a limit to long-term continuous operation.

  In a method in which hydrocracking is performed in an ebullated bed reactor using an extruded particle catalyst such as a Co-Mo system, pressure loss due to accumulation of coke, etc. is caused by vigorous mixing in the ebullated bed reactor. There is no problem of increase, and since the catalyst can be extracted and replenished during operation, it can be operated continuously for a long time while keeping the activity of the catalyst constant, and has advantages over the fixed bed system. . However, since the catalyst is circulated and operated, there is a mechanical problem such as a pump, which is difficult to operate as compared with the fixed bed system. Further, the catalyst is expensive, the reaction pressure is generally as high as 15 to 20 MPaG, and desulfurization and denitrogenation of the reaction product are insufficient. Furthermore, depending on the type of heavy oil, when the conversion rate is improved, the catalyst is deactivated, and it is necessary to frequently remove the catalyst in the reactor and supply a new catalyst to the reactor. It is operated with the conversion rate suppressed to about 50-60%.

As a technique for overcoming the disadvantages of the conventional methods as described above, petroleum heavy oil is supplied to a suspension bed (slurry bed) reactor together with an inexpensive disposable iron-based catalyst and a circulated reaction product heavy material. There is a method of obtaining a high conversion rate of 90% or more by hydrocracking reaction. In this method, unless the reaction activity of the selected iron-based catalyst is extremely bad, if the reaction pressure is increased to 15 MPa or higher, the temperature is about 450 ° C. and the reaction time is 60 to 90 regardless of the type of heavy oil. A high conversion rate of 90% or more is possible under the condition of a flow rate of heavy heavy oil (+ 525 ° C): 0 to 50% by mass (ratio of feedstock to heavy oil supply of raw materials). Such a method (hereinafter also referred to as a suspension bed type hydrocracking method using an iron-based catalyst) is described in, for example, JP-A-2001-89772.
JP 2001-88772 A

  However, this method (suspension bed type hydrocracking method using an iron-based catalyst) has a high reaction pressure, so the capital investment is higher than in the case of the above-mentioned thermal cracking method. In the suspension bed type hydrocracking method using a catalyst, it is important to reduce the pressure. Certainly, by using an inexpensive and highly active iron-based catalyst such as a natural limonite iron ore catalyst, a low pressure, for example, a reaction pressure of 10 MPa, and a reaction temperature, a reaction time as shown above, It is possible to obtain a conversion rate of 90% or more under the condition of circulating heavy residue flow rate. However, depending on the type of heavy oil (for example, a heavy oil having 13 or more condensed rings of asphaltenes in heavy oil), coke in the hydrocracking process (Toluene Insoluble (hereinafter also referred to as TI)) When the reaction product heavy substances are circulated (hereinafter also referred to as bottom recycling), the TI concentration in the heavy residue (+ 525 ° C.) to be recycled increases. In such a case, since there is almost no decomposition reactivity of TI, the decomposability of the recycled heavy residue is lowered, and the bottom recycling effect cannot be exhibited, and therefore the conversion rate and oil yield are lowered.

  In order to suppress the TI yield, it is effective to increase the reaction pressure, but this is not economical. Therefore, when a low reaction pressure is directed, even if the TI yield increases under low pressure conditions, TI is selectively extracted out of the system in order to keep the TI concentration in the heavy residue to be recycled low. (Hereinafter also referred to as TI selective removal).

  As a method of selectively extracting TI out of the system (hereinafter also referred to as TI selective removal method), a light solvent is added to a heavy reaction product containing a heavy residue (including a solid), and a sedimentation tank ( In the sedimentation-type solid-liquid separator), those that dissolve in the light solvent are extracted from the overflow of the sedimentation tank, while those that are insoluble in the light solvent (TI: mainly the solid component of the catalyst) are extracted from the underflow of the sedimentation tank. There is a so-called solvent addition precipitation type solid-liquid separation method (hereinafter also referred to as a solvent addition type precipitation type solid-liquid separation method). However, in this type of sedimentation-type solid-liquid separation method, generally, a light naphtha equivalent is used as the solvent, and the sedimentation tank is operated at a temperature of 200 ° C or higher. In order to maintain the pressure, a pressure of 1 to 2 MPa or more is required, and the solvent used needs to be recovered from both the overflow side and the underflow side.

  In order to make a more economical process when handling heavy oil with a high TI yield, a low-cost TI selective removal method (solid-liquid separation method) is desired.

  If TI selective removal is possible without the addition of a light solvent as described above (that is, not by a solvent addition method but by a non-solvent addition type solid-liquid separation method), The problem can be solved and the cost can be reduced.

  The present invention has been made paying attention to such circumstances, and the object thereof is to selectively remove TI by a sedimentation-type solid-liquid separation method in a suspension bed type hydrocracking method using an iron-based catalyst. In this case, a light solvent need not be added. That is, petroleum heavy oil containing heavy metal components is supplied to a suspension bed reactor and hydrocracked in the presence of an iron catalyst, and the hydrocracked reaction product is obtained by gas-liquid separation. TI (coke) is selectively removed from the liquid phase fluid (including heavy reaction products and TI) by sedimentation solid-liquid separation, and then the liquid phase fluid is circulated to the suspension bed reactor. TI selective removal without the addition of a light solvent during the selective removal of TI by the sedimentation-type solid-liquid separation method (that is, by the non-solvent addition-type solid-liquid separation method instead of the solvent addition method) It is an object of the present invention to provide a hydrocracking method for heavy petroleum oil that can be used.

  In order to achieve the above object, the present inventors have intensively studied, and as a result, completed the present invention. According to the present invention, the above object can be achieved.

  The present invention, which has been completed in this way and has achieved the above object, relates to a hydrocracking method for heavy petroleum oils, and the petroleum heavy oils according to claims 1 to 6 of the claims. This is a hydrocracking method (hydrocracking method of heavy petroleum oil according to the first to sixth inventions), which has the following configuration.

  That is, the method for hydrocracking petroleum heavy oil according to claim 1 is a suspension bed reactor as a reactor for hydrocracking when hydrocracking petroleum heavy oil containing heavy metal components. A hydrocracking method for petroleum heavy oil using an iron catalyst as a catalyst and comprising the following steps (1) to (4): This is a method [first invention].

(1) The reaction product from the suspension bed reactor is gasified in a high-pressure gas-liquid separator under the conditions of pressure: substantially the same pressure as the suspension bed reactor, temperature: 200 to 350 ° C. A high-pressure gas-liquid separation process that separates into a phase fluid and a liquid phase fluid (including a solid).
(2) The liquid-phase fluid separated in the high-pressure gas-liquid separation step is supplied to a low-pressure gas-liquid separator, and the gas phase fluid and the liquid phase are subjected to the conditions of pressure: normal pressure to 1 MPaG and temperature: 190 to 340 ° C. Low-pressure gas-liquid separation process that separates into fluid (including solid).
(3) The liquid phase fluid separated in the low-pressure gas-liquid separation step is supplied to a sedimentation type solid-liquid separator, and the solid is precipitated under the conditions of pressure: normal pressure to 1 MPaG, temperature: 190 to 340 ° C., A solid-liquid separation step of extracting the fluid of the upper part in the solid-liquid separator from the upper part of the solid-liquid separator, and extracting the fluid composed of the solid component and the oil component from the lower part of the solid-liquid separator;
(4) A circulation step in which part or all of the fluid extracted from the upper part of the solid-liquid separator in the solid-liquid separation step is circulated to the suspension bed reactor.

  The method for hydrocracking heavy petroleum oil according to claim 2, wherein the reaction conditions in the suspension bed reactor are as follows: reaction pressure: 6-14 MPaG, reaction temperature: 430-450 ° C, reaction time: 30-120. The method for hydrocracking petroleum heavy oil according to claim 1, wherein the second invention is.

  The method for hydrocracking heavy petroleum oil according to claim 3 is a limonite iron ore catalyst having an average particle diameter of 2 μm or less, wherein the iron-based catalyst is mechanically pulverized in a petroleum-based solvent. 3. The method for hydrocracking heavy petroleum oil according to claim 1, wherein the iron component is 0.3 to 2% by mass with respect to the amount of heavy petroleum oil [third invention].

  The method for hydrocracking petroleum heavy oil according to claim 4, wherein the temperature condition in the high-pressure gas-liquid separation step is temperature: 250 to 320 ° C. This is a method for hydrocracking a crude oil [fourth invention].

  The method for hydrocracking petroleum heavy oil according to claim 5, wherein the pressure and temperature conditions in the low-pressure gas-liquid separation step are pressure: 0.3 to 0.5 MPaG, temperature: 245 to 315 ° C, and The method for hydrocracking petroleum heavy oil according to any one of claims 1 to 4, wherein the pressure and temperature conditions in the separation step are pressure: 0.3 to 0.5 MPaG, and temperature: 245 to 315 ° C. invention〕.

  The method for hydrocracking petroleum heavy oil according to claim 6, wherein the amount of fluid circulated to the suspension bed reactor in the circulation step is the amount of heavy oil component having a boiling point in the fluid of 525 ° C or higher. The method for hydrocracking petroleum heavy oil according to any one of claims 1 to 5, wherein the amount is 10 to 100% by mass relative to the amount of petroleum heavy oil supplied to the suspension bed reactor. There is [Sixth Invention].

  According to the hydrocracking method of heavy petroleum oils according to the present invention, light weight can be obtained at the time of TI selective removal by sedimentation-type solid-liquid separation method in the hydrocracking method of a suspension bed system using an iron-based catalyst. It becomes unnecessary to add a solvent. That is, petroleum heavy oil containing heavy metal components is supplied to a suspension bed reactor and hydrocracked in the presence of an iron catalyst, and the hydrocracked reaction product is obtained by gas-liquid separation. TI (coke) is selectively removed from the liquid phase fluid (including heavy reaction products and TI) by sedimentation solid-liquid separation, and then the liquid phase fluid is circulated to the suspension bed reactor. TI selective removal without the addition of a light solvent during the selective removal of TI by the sedimentation-type solid-liquid separation method (that is, by the non-solvent addition-type solid-liquid separation method instead of the solvent addition method) You will be able to

  The hydrocracking method for petroleum heavy oil according to the present invention is a suspension bed as a reactor for hydrocracking, as described above, when hydrocracking petroleum heavy oil containing heavy metal components. A method for hydrocracking petroleum heavy oil using a reactor and an iron-based catalyst as a catalyst, comprising the following steps (1) to (4): It is a chemical decomposition method.

(1) The reaction product from the suspension bed reactor is gasified in a high-pressure gas-liquid separator under the conditions of pressure: substantially the same pressure as the suspension bed reactor, temperature: 200 to 350 ° C. A high-pressure gas-liquid separation process that separates into a phase fluid and a liquid phase fluid (including a solid).
(2) The liquid-phase fluid separated in the high-pressure gas-liquid separation step is supplied to a low-pressure gas-liquid separator, and the gas phase fluid and the liquid phase are subjected to the conditions of pressure: normal pressure to 1 MPaG and temperature: 190 to 340 ° C. Low-pressure gas-liquid separation process that separates into fluid (including solid).
(3) The liquid phase fluid separated in the low-pressure gas-liquid separation step is supplied to a sedimentation type solid-liquid separator, and the solid is precipitated under the conditions of pressure: normal pressure to 1 MPaG, temperature: 190 to 340 ° C., A solid-liquid separation step of extracting the fluid of the upper part in the solid-liquid separator from the upper part of the solid-liquid separator, and extracting the fluid composed of the solid component and the oil component from the lower part of the solid-liquid separator;
(4) A circulation step in which part or all of the fluid extracted from the upper part of the solid-liquid separator in the solid-liquid separation step is circulated to the suspension bed reactor.

In the high-pressure gas-liquid separation step (1) above, the reaction product of the hydrocracking in the suspension bed reactor is supplied to the high-pressure gas-liquid separator, and the reaction product is pressurized with the suspension bed reactor. Separation into a gas phase fluid and a liquid phase fluid (including a solid) under conditions of substantially the same pressure and temperature: 200 to 350 ° C. The liquid phase fluid thus separated contains a heavy oil component (heavy reaction product) and a solid (coke, catalyst), but also contains a light oil component in addition to these. . The heavy oil component is an oil component having a boiling point of + 525 ° C. (525 ° C. or higher), and the light oil component is an oil component other than the heavy oil component and is more than the heavy oil component. The boiling point is low.

Assuming that the amount of the light oil component in the liquid phase fluid is A ₁ , the amount of the light oil component in the reaction product is A ₀ , and the amount of the light oil component in the gas phase fluid is A ₂ , A ₁ = A ₀ -A ₂ . That is, among the light oil components in the reaction product, a part (light oil component having a lower boiling point) is contained in the gas phase fluid, but the remaining part (light oil component having a higher boiling point) is liquid. It will be contained in the phase fluid. The amount of light oil component (A ₁ ) in the liquid phase fluid is larger than that in the case of a conventional suspension bed type hydrocracking method using an iron-based catalyst (hereinafter also referred to as a conventional method). That is, this liquid phase fluid contains a relatively large amount of light oil component. This is because the temperature during the high-pressure gas-liquid separation is 200 to 350 ° C., which is lower than that in the conventional method.

  In the low-pressure gas-liquid separation step (2), the liquid phase fluid separated in the high-pressure gas-liquid separation step is supplied to the low-pressure gas-liquid separator, and the pressure is normal pressure to 1 MPaG, and the temperature is 190 to 340 ° C. Under certain conditions, gas phase fluid and liquid phase fluid (including solid) are separated. The liquid phase fluid thus separated contains a heavy oil component (heavy reaction product) and a solid (coke, catalyst), but also contains a light oil component in addition to these. . In addition, this liquid phase fluid is a state in which a part of a heavy oil component (heavy reaction product) is dissolved in a light oil component, and a solid (coke, catalyst) is mixed in this oil component.

The amount of light oil component in this liquid phase fluid (liquid phase fluid separated by the low pressure gas-liquid separator) is B ₁ , and the amount of light oil component in the liquid phase fluid separated in the high pressure gas-liquid separation step the B _0, the amount of light oil component in the gas phase fluid (vapor-phase fluid is separated in a low pressure gas-liquid separator) When B _2, in _{B 1 = B 0 -B 2 =} a 1 -B 2 is there. That is, among the light oil components in the liquid phase fluid separated in the high-pressure gas-liquid separation step, a part (light oil component having a lower boiling point) is contained in the gas phase fluid, but the remainder ( A light oil component having a higher boiling point) is contained in the liquid phase fluid. The amount of light oil component (B ₁ ) in the liquid phase fluid is larger than that in the conventional method, and a relatively large amount of light oil component is contained in the liquid phase fluid. This is because the amount (A ₁ ) of the light oil component in the liquid phase fluid separated in the high-pressure gas-liquid separation step is larger than that in the conventional method. The amount of light oil component (B ₁ ) in this liquid phase fluid is sufficient to enable selective removal of TI (coke) without adding a light solvent in the subsequent solid-liquid separation step. .

  In the solid-liquid separation step (3), the liquid phase fluid separated in the low-pressure gas-liquid separation step is supplied to a sedimentation type solid-liquid separator, and pressure: normal pressure to 1 MPaG, temperature: 190 to 340 ° C. Under this condition, the solid is settled, and the fluid in the upper part of the solid-liquid separator is extracted from the upper part of the solid-liquid separator, while the fluid composed of the solid component and the oil component is extracted from the lower part of the solid-liquid separator. In addition, the liquid phase fluid supplied to the solid-liquid separator has already dissolved a part of the heavy oil component (heavy reaction product) in the light oil component (before the supply to the solid-liquid separator). However, since this oil component is in a state where a solid (coke, catalyst) is mixed, TI can be selectively removed without adding a light solvent to the liquid phase fluid. That is, when the liquid phase fluid is supplied to the solid-liquid separator, the solid (coke, catalyst) in the liquid-phase fluid settles in the solid-liquid separator without adding a light solvent. As a result, TI is selectively removed.

  The fluid extracted from the upper part of the solid-liquid separator in this way contains the remainder of the heavy oil component (heavy reaction product) and the light oil component. This is a state in which the remainder of the heavy oil component (heavy reaction product) is dissolved in the light oil component. On the other hand, the fluid extracted from the lower part of the solid-liquid separator contains a solid component (coke, catalyst) and an oil component. This is a slurry in which a solid component is mixed with an oil component.

  Therefore, TI (coke) selective removal can be performed. In other words, TI selective removal without the addition of a light solvent during the selective removal of TI by the precipitation-type solid-liquid separation method (that is, not by the solvent addition method but by the non-solvent addition method) Can be removed.

  The reason why TI can be selectively removed without adding a light solvent is that the liquid phase fluid separated in the low-pressure gas-liquid separation step contains a relatively large amount of light oil components. In this light oil component, part of the heavy oil component (heavy reaction product) is dissolved, and the remainder of the heavy oil component (that is, coke and catalyst) is mixed with this oil component. Because. That is, since the liquid phase fluid supplied to the sedimentation type solid-liquid separator has already been in the above state (before being supplied), the heavy oil component (heavy reaction production) This is because it is not necessary to add a light solvent for such dissolution.

  In the circulation step (4), part or all of the fluid extracted from the upper part of the solid-liquid separator in the solid-liquid separation step is circulated to the suspension bed reactor. The circulated fluid is hydrocracked in the suspension bed reactor, and the heavy oil component (heavy reaction product) in the fluid contains a light oil component.

  As described above, according to the hydrocracking method of heavy petroleum oil according to the present invention, a light solvent is not added at the time of TI selective removal by the precipitation solid-liquid separation method (that is, solvent addition). TI selective removal (by non-solvent addition precipitation solid-liquid separation method). As a result, it is not necessary to increase the pressure during the precipitation-type solid-liquid separation, and the pressure can be lowered to normal pressure to 1 MPaG, and the necessity of recovering the light solvent is eliminated. That is, when adding a light solvent, a pressure of 1 to 2 MPa or more is required to keep the inside of the sedimentation tank in a liquid state, and the solvent used must be recovered from both the overflow side and the underflow side. However, in the case of the hydrocracking method for petroleum heavy oil according to the present invention, since it is not necessary to add a light solvent, the pressure can be lowered to normal pressure to 1 MPaG. It is not necessary to recover the solvent as described above, and the cost can be reduced.

In the high-pressure gas-liquid separation step (1) above, the temperature is set to 200 to 350 ° C. for the following reason. When the temperature exceeds 350 ° C., the amount of light oil component (A ₁ ) in the liquid phase fluid obtained by separation is reduced, and as a result, the light oil component in the liquid phase fluid obtained by separation in the low-pressure gas-liquid separation step. The amount of oil component (B ₁ ) is reduced, making it difficult to secure the amount necessary to enable selective removal of TI (coke) without adding a light solvent in the subsequent solid-liquid separation process. This makes it difficult to selectively remove TI without adding a light solvent. If it is below 200 ° C, the temperature of the low-pressure gas-liquid separator will be several degrees lower than the temperature of the high-pressure gas-liquid separator, so the temperature of the solid-liquid separator will operate at a maximum of about 200 ° C. If the solid-liquid separation is performed in this temperature range (below 200 ° C.), the liquid viscosity becomes higher, and the solid-liquid separation performance deteriorates. For this reason, the temperature in the high-pressure gas-liquid separation step is set to 200 to 350 ° C.

  In the high-pressure gas-liquid separation step (1), the pressure is set to substantially the same pressure as the suspension bed reactor. This pressure is a pressure when the reaction product from the suspension bed reactor is supplied to the high-pressure gas-liquid separator as it is, and may be equal to the suspension bed reactor, but lower than that. There is also a possibility. In order to include all such cases, the pressure was expressed as substantially the same pressure as the suspension bed reactor. That is, the pressure of substantially the same pressure as that of the suspension bed reactor is not limited to the same pressure as that of the suspension bed reactor, but includes the pressure when the pressure is naturally lower than that.

In the low-pressure gas-liquid separation step (2), the pressure is set to normal pressure to 1 MPaG, and the temperature is set to 190 to 340 ° C. This pressure is a gauge pressure. For example, 1 MPaG is 1.1 MPa in absolute pressure, normal pressure is 0 MPaG in gauge pressure, and 0.101 MPa in absolute pressure. Since 1 MPaG = 1 × 10 ⁶ Pa and 9.80665 × 10 ⁴ Pa = 1 kgf / cm ² (that is, 0.980665 × 10 ⁵ Pa = 1 kgf / cm ² ), 0.980665 MPa = 10 kgf / cm ² . Therefore, the above 1MPaG is 10 / 0.980665kgf / cm ^2, about 10 kgf / cm ^2. The normal pressure is 0.101 MPa (normal pressure = 1 atm = 1.033 kgf / cm ² = 1.033 × 0.0980665 MPa = 0.101 MPa).

  In the solid-liquid separation step (3), the pressure is set to normal pressure to 1 MPaG, and the temperature is set to 190 to 340 ° C. The reason why the pressure is set to normal pressure to 1 MPaG is as follows. That is, as described above, according to the hydrocracking method of heavy petroleum oil according to the present invention, TI selection can be performed without adding a light solvent when selectively removing TI by the precipitation solid-liquid separation method. Therefore, there is no need to increase the pressure during the precipitation-type solid-liquid separation, and the pressure in the solid-liquid separation step (3) can be reduced to normal pressure to 1 MPaG. Normal pressure to 1 MPaG. This leads to cost reduction.

  In the hydrocracking method for heavy petroleum oil according to the present invention, the reaction conditions in the suspension bed reactor are not particularly limited. For example, the reaction pressure is 6 to 14 MPaG, the reaction temperature is 430 to 450 ° C. Reaction time: 30 to 120 minutes [second invention].

As the iron-based catalyst, a limonite iron ore catalyst having an average particle diameter of 2 μm or less mechanically pulverized in a petroleum-based solvent is used, and the added amount is 0.3 to 0.3 as an iron component with respect to the amount of heavy petroleum oil. It is desirable to make it 2% by mass [third invention]. The use of such a limonite iron ore catalyst is more active than iron-based catalysts such as Fe ₂ O ₃ (hematite), FeS ₂ (pyrite), and FeSO ₄ (iron sulfate), and is collected in nature. This is because it is an inexpensive catalyst. When the amount added is less than 0.3% by mass, the amount of coke produced tends to increase rapidly, and when it exceeds 2% by mass, the oil yield hardly increases and the cost tends to increase.

The temperature condition in the high-pressure gas-liquid separation step is preferably set to a temperature of 250 to 320 ° C. [fourth invention]. In this way, the amount (A ₁ ) of the light oil component in the liquid phase fluid obtained by separation is increased at a higher level, and as a result, in the liquid phase fluid obtained by separation in the low pressure gas-liquid separation step. The amount of light oil component (B ₁ ) increases at a higher level, and the amount necessary to enable selective removal of TI (coke) without adding a light solvent in the subsequent solid-liquid separation process It becomes easier to secure the TI, and it becomes possible to selectively remove TI more reliably without adding a light solvent.

Pressure and temperature conditions in the low-pressure gas-liquid separation step are pressure: 0.3 to 0.5 MPaG, temperature: 245 to 315 ° C., and pressure and temperature conditions in the solid-liquid separation step are pressure: 0.3 to 0.5 MPaG, temperature : 245-315 ° C. is desirable [fifth invention]. The reason for this will be described below. In the fourth invention, it is desirable that the temperature of the high-pressure gas-liquid separation step is 250 to 320 ° C. When the liquid phase fluid of the high pressure gas-liquid separation process is supplied to the low pressure gas-liquid separation process of 0.3 to 0.5 MPaG, it is flash-separated into each gas phase and liquid phase fluid at low pressure, so the temperature is high pressure gas-liquid Lower than the separation step. The temperature in that case is 245-315 degreeC. The pressure range of 0.5 MPaG ～1MPaG low-pressure gas-liquid separation step (LPS), the amount of light oil components of the high-pressure gas-liquid separation step liquid phase fluid goes into the vapor phase (B ₂₎ is less, B ₁ is a high level Although it is maintained, the cost of equipment increases due to the higher pressure. In the LPS pressure range of normal pressure to 0.3 MPaG, the equipment cost is low, but B ₂ is relatively large (that is, B ₁ is relatively small), and the solid-liquid separation performance is slightly inferior. In the LPS pressure range of 0.3 to 0.5 MPaG, B ₁ is maintained at a relatively high level, the solid-liquid separation performance is good, and the equipment cost is low.

  The amount of fluid circulated to the suspension bed reactor in the circulation step is determined based on the amount of heavy oil component having a boiling point of 525 ° C. or higher in the fluid relative to the amount of petroleum heavy oil supplied to the suspension bed reactor. It is desirable that the amount be 10 to 100% by mass [Sixth Invention]. When the amount of circulation is less than 10% by mass, the oil yield hardly increases and the bottom recycling effect is not exhibited. On the other hand, when the circulation rate is more than 100% by mass, the oil yield is much higher than when the circulation rate is less than 10% by mass, but the increase rate of the oil yield is 10 to 100% by mass of the circulation rate. The circulation efficiency is lower than in the case of.

  An example of a process flow relating to the hydrocracking method of heavy petroleum oil according to the present invention is shown in FIGS. 1-2, (1) is a slurry preparation tank, (2) is a preheater, (3) is a suspension bed reactor, (4) is a high-pressure gas-liquid separator, and (5) is a high-pressure low-temperature gas-liquid separation. (6) is a distillation column 1, (7) is a gas purification step, (8) is a low-pressure gas-liquid separator, (9) is a settling tank, and (10) is a distillation column 2. Among these, the suspension bed reactor (3) is an example of a suspension bed reactor according to the present invention, the high pressure gas-liquid separator (4) is an example of a high pressure gas-liquid separator according to the present invention, and a low pressure gas-liquid separator. (8) corresponds to an example of a low-pressure gas-liquid separator according to the present invention, and the settling tank (9) corresponds to an example of a settling-type solid-liquid separator according to the present invention. In FIG. 1, a sedimentation type solid-liquid separator (sedimentation tank) is a batch type. The thing shown in FIG. 2 is a circulation type solid-liquid separator (sedimentation tank).

  In the present invention, among the oil components in the heavy reaction product, the heavy oil component is an oil component having a boiling point: + 525 ° C. (525 ° C. or higher), and the light oil component is the above-mentioned It is an oil component other than the heavy oil component and has a boiling point lower than that of the heavy oil component.

  Examples of the present invention and comparative examples will be described below. The present invention is not limited to this embodiment, and can be implemented with appropriate modifications within a range that can be adapted to the gist of the present invention, all of which are within the technical scope of the present invention. include.

[Example 1]
The hydrocracking method of heavy petroleum oil with heavy metals was carried out using the same equipment as in FIG. Details will be described below.

  A petroleum heavy oil containing heavy metal components was supplied to a suspension bed reactor together with an iron catalyst, and a hydrocracking reaction step was carried out for hydrocracking. At this time, a vacuum distillation residue (hereinafter referred to as VR) was used as a petroleum heavy oil containing heavy metals. As the iron-based catalyst, a limonite iron ore catalyst was used. The addition amount of this limonite iron ore catalyst was 1 mass% as an iron component with respect to the amount of heavy petroleum oil. The amount of the cocatalyst added was 1.2 times the amount of the iron component. The hydrocracking reaction conditions in the suspension bed reactor were as follows: reaction pressure: 10 MPa, reaction temperature: 450 ° C., reaction time: 90 minutes, amount of circulating distillation residue: 50% by mass of VR amount.

  The reaction product obtained in the suspension bed reactor is separated from the suspension bed reactor into a gas phase fluid and a liquid phase fluid (including a solid) by supplying the reaction product to a high-pressure gas-liquid separator. A high pressure gas-liquid separation process was performed. At this time, the pressure and temperature conditions of the high-pressure gas-liquid separator were as follows: pressure: 10 MPa, which is substantially the same pressure as the suspension bed reactor, and temperature: 310 ° C.

  The liquid-phase fluid separated in the high-pressure gas-liquid separation step was supplied to a low-pressure gas-liquid separator, and a low-pressure gas-liquid separation step for separating the gas-phase fluid and the liquid-phase fluid (including solid) was performed. At this time, the pressure and temperature conditions of the low-pressure gas-liquid separator were set to pressure: 0.5 MPa, temperature: 300 ° C.

  The liquid phase fluid separated in the low-pressure gas-liquid separation step was supplied to a sedimentation type solid-liquid separator (sedimentation tank) and allowed to stand for 30 minutes under conditions of pressure: 0.5 MPa and temperature: 300 ° C. Thereafter, the upper layer fluid in the settling tank is inserted from the suction port of the insertion tube (its final end, ie, the suction port is located at a height of 85% of the settling tank height H) inserted from the top of the settling tank. And the remaining lower layer fluid was removed from the lower part of the settling tank. Thus, the solid-liquid separation process was performed.

  Table 1 shows the composition of the upper layer fluid and the lower layer fluid in the settling tank extracted in the solid-liquid separation step. From Table 1, it can be seen that TI and catalyst are concentrated in the lower layer fluid, and the amount of TI and catalyst in the upper layer fluid in the sedimentation tank is small.

  A circulation step was performed in which a part of the upper layer fluid in the sedimentation tank extracted in the solid-liquid separation step was circulated to the suspension bed reactor.

  As a result, the conversion rate was 91%, the distillation residue (+ 525 ° C.) yield: 7.3% by mass with respect to the VR amount, and the oil yield: 85% by mass with respect to the VR amount. Here, the conversion rate is obtained by the following formula (1).

    Conversion (%) = 100 × [(in raw material VR + wt% at 525 ° C.) − (Distillation residue yield)] / (raw material VR + wt% at 525 ° C.) ---------- -------- Formula (1)

  The fraction composition of the raw material VR was as shown in Table 2.

[Comparative Example 1]
The hydrocracking reaction step was performed under the same conditions in the same suspension bed reactor using the same petroleum heavy oil and iron catalyst as in Example 1. This reaction product was supplied to a high-pressure gas-liquid separator, and a high-pressure gas-liquid separation step was performed. At this time, the pressure and temperature conditions of the high-pressure gas-liquid separator were set to pressure: 10 MPa, which is substantially the same pressure as the suspension bed reactor, and temperature: 370 ° C. The liquid phase fluid separated in this high-pressure gas-liquid separation step was supplied to a low-pressure gas-liquid separator, and the low-pressure gas-liquid separation step was performed under the same pressure and temperature conditions as in Example 1.

  That is, the temperature condition of the high-pressure gas-liquid separator is set to a temperature (370 ° C.) higher than that in the case of Example 1 (310 ° C.). A liquid separation process and a low-pressure gas-liquid separation process were performed.

  The liquid phase fluid separated in the low-pressure gas-liquid separation step is supplied to a settling tank, left to stand for 60 minutes under the conditions of pressure: 0.5 MPa, temperature: 300 ° C., and the same method as in Example 1 Thus, the upper layer fluid in the sedimentation tank was extracted, and the remaining lower layer fluid was extracted. That is, the standing time in the sedimentation tank was set longer (60 minutes) than in Example 1 (30 minutes), and the solid-liquid separation process was performed in the same manner as in Example 1 except for this point. .

  The composition of the upper layer fluid and the lower layer fluid in the settling tank extracted in the solid-liquid separation step was as shown in Table 3. From Table 3, the concentration of TI and catalyst in the lower layer fluid is extremely small compared to that in Example 1, and the amount of TI and catalyst in the upper layer fluid in the settling tank is compared with that in Example 1. It can be seen that the number is extremely high.

  A circulation step was performed in which a part of the upper layer fluid in the sedimentation tank extracted in the solid-liquid separation step was circulated to the suspension bed reactor.

  As a result, the conversion rate was 81%, the distillation residue (+ 525 ° C.) yield: 15.6% by mass with respect to the VR amount, and the oil yield: 75.1% by mass with respect to the VR amount. Here, the conversion rate is obtained by the above formula (1).

  As described above, in the case of Comparative Example 1, the concentration of TI and catalyst in the lower layer fluid in the solid-liquid separation step, although the standing time in the sedimentation tank is long (60 minutes). The amount of TI and catalyst in the upper layer fluid in the sedimentation tank is large, and for this reason, the conversion rate when circulating the upper layer fluid in the sedimentation tank to the suspension bed reactor and hydrocracking reaction is low, The distillation residue (+ 525 ° C) yield is high, and the oil yield is low.

  On the other hand, in the case of Example 1, the concentration of TI and catalyst in the lower layer fluid in the solid-liquid separation process is low, although the standing time in the sedimentation tank is short (30 minutes). The amount of TI and catalyst in the upper layer fluid in the sedimentation tank is extremely low, and therefore the conversion rate when the upper layer fluid in the sedimentation tank is circulated to the suspension bed reactor and subjected to the hydrocracking reaction is extremely high. High, distillation residue (+ 525 ° C.) yield is very low, and oil yield is very high.

  This is because the temperature in the high-pressure gas-liquid separator is lower in the case of Example 1 than in the case of Comparative Example 1, and the TI selective removability is extremely excellent. That is, in the case of Comparative Example 1, the TI selective removability is low, and in order to improve the above conversion, distillation residue (+ 525 ° C.) yield, and oil yield to the levels of Example 1, In the case of Example 1, a light solvent is required for selective removal of TI by the sedimentation-type solid-liquid separation method. This is because a high level of TI selective removal can be achieved without addition.

  The method of hydrocracking petroleum heavy oil according to the present invention comprises hydrocracking a petroleum heavy oil containing heavy metal components in the presence of an iron catalyst in a suspension bed reactor, and the reaction product. Since the above-mentioned effects can be obtained when the heavy components therein are circulated to the suspension bed reactor for hydrocracking, it is suitable as a hydrocracking method for petroleum heavy oil containing heavy metal components. It can be used, and it is useful because it is economically improved.

It is a schematic diagram which shows the example of the apparatus for performing the hydrocracking method of petroleum heavy oil which concerns on this invention. It is a schematic diagram which shows the example (an example different from the example shown in the said FIG. 1) of the apparatus for performing the hydrocracking method of petroleum heavy oil which concerns on this invention.

Explanation of symbols

(1) --Slurry conditioning tank, (2) --Preheater, (3) --Suspension bed reactor, (4) --High pressure gas / liquid separator, (5) --High pressure low temperature gas / liquid separator (6) --Distillation column 1, (7) --Gas purification step, (8) --Low pressure gas-liquid separator, (9) --Sedimentation tank, (10) -Distillation column 2.

Claims (6)

Hydrocracking of heavy petroleum oils using a suspension bed reactor as a reactor for hydrocracking and using an iron-based catalyst as a catalyst for hydrocracking petroleum heavy oils containing heavy metal components A method for hydrocracking petroleum heavy oil, comprising the following steps (1) to (4):
(1) The reaction product from the suspension bed reactor is gasified in a high-pressure gas-liquid separator under the conditions of pressure: substantially the same pressure as the suspension bed reactor, temperature: 200 to 350 ° C. A high-pressure gas-liquid separation process that separates into a phase fluid and a liquid phase fluid (including a solid).
(2) The liquid-phase fluid separated in the high-pressure gas-liquid separation step is supplied to a low-pressure gas-liquid separator, and the gas phase fluid and the liquid phase are subjected to the conditions of pressure: normal pressure to 1 MPaG and temperature: 190 to 340 ° C. Low-pressure gas-liquid separation process that separates into fluid (including solid).
(3) The liquid phase fluid separated in the low-pressure gas-liquid separation step is supplied to a sedimentation type solid-liquid separator, and the solid is precipitated under the conditions of pressure: normal pressure to 1 MPaG, temperature: 190 to 340 ° C., A solid-liquid separation step of extracting the fluid of the upper part in the solid-liquid separator from the upper part of the solid-liquid separator, and extracting the fluid composed of the solid component and the oil component from the lower part of the solid-liquid separator;
(4) A circulation step in which part or all of the fluid extracted from the upper part of the solid-liquid separator in the solid-liquid separation step is circulated to the suspension bed reactor.   The hydrocracking of heavy petroleum oil according to claim 1, wherein the reaction conditions in the suspension bed reactor are: reaction pressure: 6-14 MPaG, reaction temperature: 430-450 ° C, reaction time: 30-120 minutes. Method.   The iron-based catalyst is a limonite iron ore catalyst having an average particle size of 2 μm or less, which is mechanically pulverized in a petroleum-based solvent, and the amount added is 0.3-2 mass as an iron component with respect to the amount of heavy petroleum-based oil. The method for hydrocracking heavy petroleum oils according to claim 1 or 2, wherein the hydrocracking method is at least%.   The method for hydrocracking petroleum heavy oil according to any one of claims 1 to 3, wherein a temperature condition in the high-pressure gas-liquid separation step is a temperature: 250 to 320 ° C.   Pressure and temperature conditions in the low-pressure gas-liquid separation step are pressure: 0.3 to 0.5 MPaG, temperature: 245 to 315 ° C., and pressure and temperature conditions in the solid-liquid separation step are pressure: 0.3 to 0.5 MPaG, temperature The method for hydrocracking petroleum heavy oil according to any one of claims 1 to 4, wherein the temperature is 245 to 315 ° C. The amount of fluid circulated to the suspension bed reactor in the circulation step is determined based on the amount of heavy oil component having a boiling point of 525 ° C. or higher in the fluid relative to the amount of petroleum heavy oil supplied to the suspension bed reactor. The method for hydrocracking petroleum heavy oil according to any one of claims 1 to 5, wherein the amount is 10 to 100% by mass.

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