KR0138687B1 - Dispersion catalyst and reaction process for hydrotreatment of high-sulfur heavy residual oil - Google Patents

Abstract

The present invention is directed to a catalyst that promotes denitrification, demetallization and deasphaltenation reactions including desulfurization by directly injecting oil-dispersed catalyst precursors directly into high-residue heavy residues, which are reaction raw materials, and reacting them under high pressure with hydrogen. In the hydrogenation process of heavy oil, which is produced naturally and performs desulfurization reaction, the catalyst precursor material is improved by improving the intrinsic activity for the desulfurization reaction of the dispersion catalyst and continuously fixing the dispersion catalyst of the fine particles produced during the reaction in the reactor. The present invention relates to a method and a reaction process configuration for reducing the amount of oil used and increasing the desulfurization efficiency of heavy oil. That is, the catalyst precursor containing catalytically active metal components such as cobalt and molybdenum is directly injected into heavy oil, a reaction raw material oil, and high-pressure hydrogen (70-150 atm), which is a condition for heavy oil hydrogenation, at a high temperature (390-450 ° C). In the hydrogenation process in which CoS _x and MoS ₂ particles of very fine size are dispersed in the reaction oil when the reaction is carried out under the above conditions, and the hydroprocessing reaction including desulfurization of heavy oil proceeds by the catalytic action, Is maintained at 70% or more in the reaction crude oil of the catalyst precursor material to improve the intrinsic activity of the dispersion catalyst for the desulfurization reaction and by using activated carbon granules as a carrier to immobilize the dispersed catalyst particles in the reactor, these catalysts are continuously The catalyst in the reactor is controlled by controlling the concentration of catalyst precursors dispersed in the feedstock oil according to the desulfurization rate. It relates to the construction of the heavy oil in the reaction process and the desulfurization process for deriving the availability and the reaction efficiency at the maximum.

Description

Dispersion Catalyst and Reaction Process for Hydrogenation of High Sulfur Heavy Residue

1 is a schematic diagram of a fixed configuration of the present invention.

FIG. 2: Schematic diagram of the activated carbon-expanded bed reactor of FIG. 1.

3 is a graph of the reactor input concentration of the dispersion catalyst and the resulting desulfurization rate with the passage of the reaction duration in the present invention.

Explanation of symbols on the main parts of the drawings

1A: Heavy crude oil tank containing elemental sulfur and catalyst precursors dispersed therein

1B: pure heavy crude oil tank 2: heavy crude oil supply line

3: pressurized hydrogen supply line 4: hydrogen and heavy raw material oil preheater

5: activated carbon expanded bed reactor 6: primary reaction product oil

7: fixed bed reactor packed with supported catalyst

8: final reaction product oil 9: gas-liquid reaction product oil separator

10: gas product outlet line 11: liquid product oil outlet line

The present invention is directed to a catalyst that promotes denitrification, demetallization and deasphaltenation reactions, including desulfurization reactions by directly injecting oil dispersion catalyst precursors directly into high-residue heavy residues, which are reaction raw materials, and reacting them with high-pressure hydrogen under high temperature conditions. In the hydrogenation process of heavy oil, which is produced naturally and performs desulfurization reaction, the catalyst precursor material is improved by improving the intrinsic activity for the desulfurization reaction of the dispersion catalyst and continuously fixing the dispersion catalyst of the fine particles produced during the reaction in the reactor. The present invention relates to a method and a reaction process configuration for reducing the amount of oil used and to improve the desulfurization efficiency of heavy oil. More specifically, catalytic precursors containing catalytically active metal components such as cobalt and molybdenum are directly added to the heavy oil, which is a reaction oil. High pressure hydrogen (70) under normal heavy oil hydroprocessing conditions. ~ 150 atm) and at high temperature (390 ~ 450 ℃), very fine sized CoS _x and MoS ₂ particles are dispersed in the reaction oil, and their catalysis causes the hydroprocessing reaction including desulfurization of heavy oil. In the advanced hydroprocessing method, the hydroprocessing process including desulfurization is carried out while maintaining the desulfurization rate of 70% or more. In the hydroprocessing method, the input amount of the catalyst precursor material into the reaction raw material oil is maintained while maintaining the desulfurization rate of 70% or more. In order to reduce and improve the reaction efficiency, cobalt and molybdenum catalyst precursors are mixed and dispersed simultaneously in the reaction raw material oil to improve the intrinsic activity of the dispersion catalyst for the desulfurization reaction, and the activated catalyst particles are used as a carrier to immobilize the catalyst particles in the reactor. As these catalysts continue to participate in the reaction, they remove the concentration of catalyst precursors Controlled according to the ratio relates to the construction of the heavy oil in the reaction process and the desulfurization process for deriving a reactor for the catalytic activity and the reaction efficiency at the maximum.

In general, heavy oils such as atmospheric residue oil or vacuum residue oil contain a large amount of asphaltenes, as well as sulfur, nitrogen, and impurities such as nickel and vanadium in very high concentrations. In order to produce light, high quality dairy products from heavy oils, chemical removal of the impurities present in the heavy oils is required. Impurities in heavy oils are converted (asphaltene) or removed (sulphurene) by the reaction of heavy oils for 1-2 hours at high pressure hydrogen (70-150 atm) and high temperature (350-450 °) hydroprocessing conditions. , Nitrogen, and metals), and these reactions occur in the presence of a catalyst. This process using a catalyst and hydrogen is called a hydrotreating process.

When the catalysts used in the heavy oil hydrogenation process developed so far are classified according to their types, there are a supported catalyst used by supporting the active catalyst powder on a porous support and a dispersion catalyst used by uniformly dispersing it in heavy oil as a reaction raw material oil. Currently, the supported catalyst mainly used in the commercial heavy oil hydroprocessing process is cobalt (nickel) and molybdenum in porous carriers having high thermal, chemical stability, mechanical strength and high specific surface area such as gamma alumina (γ-alumina). It is a catalyst that has been used in the desulfurization process of distilled oils such as naphtha, kerosene, diesel and vacuum gas since it has the advantage of high intrinsic activity and selectivity of catalyst for desulfurization reaction. admit. However, the supported catalyst has a high activity deterioration due to the sticking of by-product coke and metal components in the crude oil in the reaction, and thus has a high content of impurity components such as asphaltenes, nickel and vanadium, which cause deactivation by coking and poisoning. In case of treating heavy oil directly, the reaction efficiency is low and the consumption of catalyst is very large.

The dispersion catalyst is used by directly dispersing the catalyst precursor material containing the active metal components (Co, Ni, Mo, W) in the heavy oil as a reaction raw material. Catalyst precursors can be used in three types: insoluble inorganic compounds (micropowder-dispersed), water-soluble or solvent-soluble compounds (dispersed in water or a specific solvent), and oil-soluble compounds (direct dispersion). dispersed catalyst precursor is normally (370 ~ 390 ℃) temperature of 70 atm or more of the hydrogen and the sulfurized metal (CoS _X is thermally decomposed to a very fine size of the catalytically active material in terms of sulfur is present as elemental sulfur or hydrogen sulfide _, NiS _x , MoS ₂ , WS ₂ ) and are uniformly present in the reaction crude oil. Therefore, the dispersion catalyst has several advantages in the hydrogenation of heavy oil as compared to the case of the supported catalyst.

First, since the deactivation of the catalyst is hardly a problem due to the metal components in the coating and the raw material oil, smooth processing of heavy oil having a high content of asphaltene and metal components is possible.

Second, since there is no diffusion resistance to the catalytic activity point of relatively large oil molecules such as asphaltenes and high boiling point fractions, the utilization of catalytic metals is high and the reactions to macromolecular molecules proceed efficiently.

Third, because of the high concentration of the catalyst per unit volume in the reaction column, the contact with the reaction oil and hydrogen is maximized, and coke by-products are greatly suppressed.

Despite these various advantages, there are the following improvements in the technology of using the dispersion catalyst as a heavy oil hydroprocessing catalyst.

First, the dispersion catalyst was originally developed as a hydrocracking catalyst for the decomposition of heavy oils such as vacuum residue or liquefaction of coal, which is difficult to process as a supported catalyst due to the rapid deterioration of activity. The activity of decomposing heavy hydrocarbons is greater than that of the reaction. In the hydrogenation process of heavy oil, the main purpose is to remove impurities such as asphaltenes, sulfur, nitrogen and metals. Therefore, the higher the hydroprocessing activity of the catalyst, the better. However, the relatively high decomposition activity promotes the decomposition of the oil excessively. And the increase in the consumption of process hydrogen.

Secondly, the stirred slurry reactor, which is used mainly in the hydrogenation process using dispersion catalysts, requires mechanical agitation of the reactants, and the hydrotreatment efficiency of the reactants such as desulfurization rate is compared based on the unit volume of the reactor. It is lower than plug flow reactor.

Thirdly, in the dispersion catalyst reaction process to date, since the catalytically active component of the fine particles generated in the reaction oil flows out along with the reaction oil flowing out of the reactor, the catalyst component can be used only once.

Therefore, in order to increase the concentration of the catalyst particles in the reactor, a method of increasing the input dispersion amount of the reaction raw material oil of the catalyst precursor material or recovering the catalyst particles from the reaction product oil using a separate external device is used. Causes an increase in operating costs. The reason why most metal catalysts, such as iron, which are inexpensive and low in activity, is used as a dispersion catalyst in most of the process of dispersing catalyst, is that it is difficult to recover the catalyst dispersed in the reaction raw material oil. to be. Highly active metals such as cobalt, nickel, molybdenum, and tungsten, which have high reaction activity, have relatively high values, so that they can be used as dispersion catalysts.

In the present invention, while utilizing the various advantages of the above and the dispersion catalyst in utilizing the dispersion catalyst in the hydroprocessing process of the high sulfur heavy oil, the above object is to complement and improve the above disadvantages as follows.

First, in order to improve the intrinsic activity of the dispersion catalyst for the heavy oil deactivation reaction, each catalyst precursor such as cobalt-molybdenum, nickel-molybdenum, or nickel-tungsten is composed of two-component systems having a catalytic activity enhancement effect. It was used by mixing and dispersing in the reactant oil, which resulted in much higher desulfurization rate than the catalyst metal component, while reducing the process's hydrogen consumption by relatively suppressing the decomposition of heavy oil to light oil. Can be.

Second, by designing an expanded bed tubular reactor filled with about 80-90% of the total reactor volume with activated carbon granules of appropriate size, the existing dispersant catalyst is prepared by inducing the immobilization of catalyst particles in the reaction oil into activated carbon. It solves the problem of one-time use of the catalyst and the problem of recovery of catalyst from the reaction product oil, which are the biggest problems in the process, and naturally leads to an increase in the catalyst concentration in the reactor, thereby inhibiting the decomposition of heavy oil into light oil and desulfurization. The hydroprocessing performance was improved to 70% denitrification, 80% demetallization and 65% deasphalting. In addition, since the dispersed catalyst particles are fixedly supported on the activated carbon in the reactor, a separate facility for recovering the dispersed catalyst metal from the reaction product oil is not required. Thus, the process cost is greatly reduced compared to the existing process, Extraction of catalytic metals is easy.

Third, while maintaining the reactivity in this state, the concentration of the catalyst precursor to the reaction raw material is periodically adjusted to reduce the total amount of the precursor used in the dispersion catalyst.

In order to achieve the above object, the present invention directly disperses oil-dispersed catalyst precursor material in the high sulfur heavy residue residue, which is a reaction raw material oil, and reacts it under high pressure hydrogen and high temperature conditions to denitrification, demetallization and deasulfation reaction. In the hydrogenation process of heavy oil, which naturally generates a catalyst which promotes the Palten reaction and performs desulfurization reaction, (1) molybdenum naphthenate, which is a main catalyst, is a dispersion catalyst precursor in heavy oil, which is a reaction raw material oil. Cobalt naphthenate is dispersed as a cocatalyst, and the dispersion ratio is dispersed so that the atomic ratio of Co / (Co + Mo) is 0.3, and (2) in the reaction oil to promote activation of the dispersion catalyst precursor dispersed in the reaction oil. The reaction mixture prepared by adding and dispersing elemental sulfur to about 500ppm and (3) loading activated carbon granules into the reactor was prepared in (1) and (2). By immobilizing and supporting the catalytically active components naturally generated in the process of reacting the root oil with a temperature of 400 ° C. or higher and a hydrogen pressure of 70 atm or higher, the amount of catalyst precursor is reduced overall, the catalyst metal is recovered from the reaction oil, and the catalyst supported on the activated carbon. (4) to increase the reaction efficiency by continuing to remain in the reactor and (4) heavy oil, a reaction raw material oil having a total dispersion concentration of 500 ppm or less of the dispersion catalyst precursor, is prepared as a separate reaction raw material oil tank and used for the reaction. By controlling the reactor input of pure heavy crude oil which does not contain the catalyst and the catalyst, the amount of catalyst precursor material can be reduced as a whole while maintaining the reaction rate at a desired level, and (5) the oil-dispersed catalyst precursor and activated carbon expanded bed reactor Heavy oil deoxidation or can Configured as a part of the screen processing step characterized by the step of using.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings and an operation process.

end. Preparation of Reaction Raw Material Oil

As shown in FIG. 1, the heavy oil to be hydrotreated may be treated with atmospheric residue oil or vacuum residue oil irrespective of its asphaltene content or metal component content, and the raw material oil tank 1A has an element as a dispersion catalyst precursor. The catalyst-containing heavy oil which disperse | distributed sulfur, cobalt naphthenate, and molybdenumate to about 500 ppm based on the catalyst metal component concentration is prepared, and the heavy oil which does not contain a catalyst is prepared in the raw material oil tank 1B. The dispersion catalyst precursor dispersed in the heavy crude oil is dispersed so that the dispersion atomic ratio of Co / (Co + Mo) is 0.3, and in addition, the elemental sulfur is dispersed about 500 ppm to promote the activation of the dispersion catalyst precursor dispersed in the reaction oil.

I. Reaction in Activated Carbon Expansion Bed Tubular Reactor

(B-1). The designed expansion bed tubular reactor is filled with activated carbon pellets to account for about 80-90% of the total reactor volume. The activated carbon layer charged in the reactor initially sits down at the bottom of the reactor, but expands through the reactor as shown in FIG. 2 due to the vertical rise of the reaction oil and hydrogen during the reaction. At this time, since 20-30% of the total volume of the reactor is present as a void volume, there is no problem such as pressure gradient in the axial direction of the reactor as in the conventional fixed bed reactor or blockage of the reaction phase. Because the characteristics are induced close to the plug flow, the reactivity is much higher than the conventional stirred slurry reactor.

(B-2). The catalyst precursor-containing heavy oil of the crude oil tank 1A is first pumped into the reactor, and mixed with pressurized hydrogen of 70 atm or higher supplied to the pressurized hydrogen supply line 3 before entering the preheater 4 operated at 350 ° C. Enter the activated carbon expanded bed reactor. The catalyst precursor, which is mixed and dispersed in the reactant oil, is reacted with H ₂ S derived from elemental sulfur introduced in the reactor at a temperature of 420 ° C. or higher to generate fine catalytically active particles such as MoS ₂ and CoSx. In addition, these catalyst particles not only participate in the reaction in the state of being dispersed in the reaction oil in the reactor, but also adhere to the pore surface of the charged activated carbon so that a kind of activated carbon supported catalyst is continuously formed in the reactor as the reaction duration elapses. As a result, the hydrogenation efficiency of the heavy oil is naturally increased as shown in FIG. 3 as the reaction duration elapses.

That is, since both the catalyst in the dispersed state and the activated carbon supported catalyst in the reaction oil exhibit catalytic activity, the hydrogenation efficiency of the catalyst precursor is greatly increased.

(B-3). As shown in P1 of FIG. 3, the desulfurization rate increases as the reaction duration time elapses when the heavy catalyst-containing heavy oil continues to be reacted, while reducing the pumping amount of the crude oil tank 1A crude oil at the time when the rate of increase slows. Start pumping pure heavy crude oil (1B) (see P2 in Figure 3). As a result, the catalyst dispersion concentration of the heavy oil entering the reactor is lowered, but the sulfur conversion rate and the asphaltene conversion are maintained as usual by the activated carbon supported catalyst already present in the reactor. When the reaction rate decreases below 70% for desulfurization and denitrification, 80% for demetallization, and 65% for deaspartment, the reaction rate is lowered by relatively increasing the input amount of the crude oil tank 1A to recover the reaction rate. At that time, the reaction proceeds in such a manner that the input amount of the raw material oil tank 1A is relatively increased to restore the reaction rate. If the reaction rate decreases despite increasing the feed catalyst dispersion catalyst concentration (see P3 in Fig. 3), the pores of the activated carbon charged in the reactor are saturated. Replace with and proceed with the reaction.

In FIG. 3, P1 supplies only the catalyst-containing reaction raw material oil of the heavy crude oil tank containing elemental sulfur and the catalyst precursor in order to increase the sulfur conversion rate in the activated carbon expansion bed reactor to a certain level and to increase the catalyst concentration in the reactor. It is the initial period of operation, and P2 is a step of gradually reducing the concentration of the catalyst in the feedstock oil supplied to the reactor from the point where the concentration of the catalyst in the reactor is sufficiently accumulated to maintain the desulfurization rate of the primary product oil, that is, the element This is a period of reducing supply of crude oil tank crude oil containing sulfur and catalyst precursors and increasing the supply of pure heavy crude oil tank crude oil, and P3 restores the concentration of the catalyst in the reactor when the desulfurization rate of the primary product oil decreases. Heavy source containing elemental sulfur and catalyst precursors as in P1 A period for supplying the raw oil tank.

All. Reaction in a Fixed Bed Tubular Reactor Filled with Supported Catalysts

The reaction product oil, which has passed through the activated carbon expanded bed tubular reactor (6) in the dispersion catalyst, has a specific activity for desulfurization reaction with 70, 65 and 85% reduction in sulfur, asphaltene and metal content, respectively, compared to the original crude oil. Is fed into a fixed bed tubular reactor (7) filled with a very high supported catalyst, CoMo / Υ-Al ₂ O ₃ or NiMo / γ-Al ₂ O ₃ . Since most of the impurities in the heavy oil, which is the cause of the rapid deactivation of the supported catalyst, are treated by this reactor in the state of being removed by the activated carbon expanded bed reactor, the volume of the reactor can be reduced, that is, the LHSV can be increased. There is an effect that the surface of the filled expensive supported catalyst is much longer. Through this reactor operating at temperatures above 400 ° C, heavy crude oil is ultimately produced as desulfurized oil with sulfur content below 0.5wt%, asphaltene content below 2.0wt% and total metal content below 25ppm. Through (9) it is separated into gaseous product (10) and liquid product (11), respectively.

The present invention is expected to significantly reduce the process cost and the effect of increasing the reaction efficiency compared to the existing process.

Claims (5)

Directly spray oil-dispersed catalyst precursors on high-residue heavy residues, which are reactant oils, and react them under high pressure with hydrogen under high temperature conditions to naturally produce catalysts that promote desulfurization, denitrification, demetallization and deasphalten reactions. In the hydrogenation process of heavy oil, which performs desulfurization reaction using the same, dispersing super-precursor is dispersed in the heavy oil, which is the reaction raw material, as the main catalyst and the cocatalyst, and the dispersion ratio is 0.3 in the atomic ratio of Co / (Co + Mo). To this end, in order to promote the activation of the dispersion catalyst precursor dispersed in the reaction oil, the elemental sulfur is added and dispersed to about 500 ppm in the reaction oil, and activated carbon granules are charged into the reactor to make the reaction raw material secreted from the above 400 ° C. Highly catalytically active components naturally produced during the reaction at temperatures above 70 atm and hydrogen pressure Dispersion catalyst for hydrogenation of high sulfur heavy residues, characterized in that the overall amount of catalyst precursor is reduced, the catalyst metal is recovered from the reaction oil, and the catalyst supported on activated carbon is kept in the reactor to increase the reaction efficiency. Reaction process. The process of claim 1, wherein the main catalyst is used as molybdenum naphthenate. 2. The process of claim 1, wherein the casting catalyst is used as cobalt naphthenate. Heavy oil, which is a reaction raw material oil having a total dispersion concentration of 500 ppm or less, is prepared as a separate reaction raw material tank and used for the reaction, and the reactor input of this raw oil and the reactor input of pure heavy raw material oil containing no catalyst are relatively used. Dispersion catalyst reaction process for the hydrogenation of high sulfur heavy residues, characterized in that the overall amount of catalyst precursor material can be reduced while maintaining the reaction rate at a desired level. 5. The process of claim 4, wherein the oil dispersion catalyst precursor and the activated carbon expanded bed reactor are configured and used as part of a heavy oil desulfurization or hydroprocessing process.