JPH02242886A - Hydrogenolysis reaction of hydrocarbon oil - Google Patents

Abstract

PURPOSE:To contrive to improve the contact efficiency between fluid and catalyst layer by preventing the pressure loss and block formation in catalyst layer by means of disposing the raw material-supplying tube with a double pipe structure onto a catalyst-filling reactor, and blowing raw material oil and hydrogen gas supplied from the upper portion of the reactor to the lower portion of the catalyst layer under indirect preheating of the raw material oil and hydrogen gas, respectively. CONSTITUTION:A hydrocarbon oil from the upper portion of a raw material- supplying pipe 1 and hydrogen gas in an amount of 1.5-3 times that of the hydrocarbon oil from the upper portion of a raw material pipe 2 indirectly pre-heated by the heating of a catalyst layer 3, respectively, are supplied into a reactor filled with the catalyst having an average particle size of 0.2-8mm, and simultaneously carried downward, followed by blowing both the raw material oil and hydrogen gas into the lower portion of the catalyst layer 3 in a high speed. Thereby, the particulate catalyst, the hydrocarbon oil and the hydrogen gas are mixed with stirring and boiled to perform the liquid phase hydrogenation reaction while preserving conditions of temperature at 340-480 deg.C and pressure of 50-300kg/cm<2>G.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for treating hydrocarbon oils with hydrogen in the presence of a catalyst. More specifically, the present invention relates to an improvement in a method for hydrocracking heavy hydrocarbon oils by catalytic reaction treatment under high pressure and high temperature.

Although hydroprocessing of heavy oils is economically preferable, there are many difficult problems. One of these problems was the formation of coke on the catalytic material, with accompanying blockage of the catalytic bed. A second problem was the difficulty of maintaining a stable and satisfactory reaction temperature when the reaction that occurs is highly exothermic.

It is an object of the present invention to provide a hydrocarbon solution that eliminates pressure loss and blockage of the catalyst layer due to the formation of coke on the catalyst material, and that allows the capacity of the device to be reduced by improving the contact efficiency between the catalyst fluid and the catalyst layer. An object of the present invention is to provide a method for hydrocracking reaction of oil.

U.S. Pat. No. 2,987,465 discloses that the solid is in an expanded state, occupying at least 10% more volume than in the resting state of the mass, and is in irregular motion within a gas-liquid system. describes the contacting of gases, liquids, and solids under conditions. A population of solid particles in such irregular motion in a liquid or gas-liquid phase can be called a "boiling".

Ebullated beds completely eliminate the difficulties traditionally experienced in conventional fixed bed reactors due to large pressure drops and blockages caused by carbon formation, and even moreover, fixed bed reactors inherently suffer from the It has now become possible to use highly active catalyst particles of relatively small particle size, which would otherwise not have been possible.

However, when performing a conventional ebullated bed reaction, raw materials (heavy hydrocarbon oil and hydrogen gas) were supplied from the lower part of the reactor and fluidized. This method requires a distribution device, such as a distribution plate, to increase the accumulation of catalyst in the feed nozzle and the dispersion of liquids and gases in order to feed the raw material from below.

However, this method has various drawbacks as described below.

The first is the irregularity of the dispersion effect due to the distribution device.

In other words, the liquid and gas supplied from the raw material supply nozzle are
In order to increase the contact efficiency of liquid and solid phase, it is necessary to place a distribution device at the bottom of the reactor. - For boat fishing, it is difficult to select a distribution device, and the distribution effect changes due to clogging with wear particles caused by irregular movement of the catalyst, so it is necessary to provide an effective distribution device. That has its difficulties. In addition, clogging of the distribution device due to the catalyst wear debris causes an increase in pressure loss, which may even lead to a shutdown of the entire device.

In addition, structurally, the lower part of the reactor has a complicated structure due to the installation of a distribution device, the increase in the number of nozzles, etc., and it has the disadvantage that it is difficult to completely extract the catalyst, clean it, etc.

The present invention has been made to overcome the drawbacks of these conventional methods, and has no pressure loss over time, easy temperature control, the ability to use catalysts with finer particle sizes, and a heavy weight catalyst. This provides an effective hydrocracking method for quality oil.

In the present invention, a raw material supply pipe with a double pipe structure is installed in a reaction vessel filled with a catalyst, and raw material oil and hydrogen are supplied from the upper part of the supply pipe, and in the meantime, both are preheated by indirect heating of the catalyst layer. Oil and hydrogen are injected into the lower part of the catalyst layer, and the raw oil, hydrogen, and catalyst are stirred and mixed to cause a reaction.

That is, in the present invention, when hydrogen is brought into contact with liquid oil through a catalyst under high temperature and high pressure to hydrocrack it, hydrogen is added to the liquid oil in a reactor filled with a catalyst having an average particle size of 0.2 to 8 mm. Hydrocarbon oil is continuously supplied from the upper part of the outside and passed through the catalyst layer downward while exchanging heat with the catalyst in a non-contact state, and the hydrocarbon oil is also supplied from the upper part of the outside into the hydrocarbon oil. After feeding 1.5 to 3 times the maximum amount of hydrogen downward while exchanging heat with the hydrocarbon oil and the catalyst in a non-contact state, the hydrocarbon oil is directed toward the center of the bottom of the reactor. The above-mentioned gas is ejected into the hydrocarbon oil that is gushing out.

By dispersing and ejecting hydrogen at high speed, the granular catalyst, hydrocarbon oil, and hydrogen are stirred and mixed.
This is a method for hydrocracking hydrocarbon oil, characterized by carrying out liquid phase hydrogenation while boiling under predetermined substantially isothermal and isobaric conditions at 480° C. and 50 to 300 kg/cdG.

The present invention will be explained below based on the embodiments shown in FIGS. 1 and 2. In the figure, reference numeral 1 denotes a liquid oil supply pipe (outer pipe) which is inserted to the lower part of the reactor 4 in the form of a double pipe with the hydrogen supply pipe 2. Hereinafter, this will be collectively referred to as the raw material supply pipe.

Liquid oil and hydrogen are mixed and dispersed at the raw material supply pipe outlet.
It is supplied to the fluidized catalyst bed 3. Liquid oil and hydrogen are supplied to the raw material supply pipe 1. By indirectly exchanging heat with the catalyst layer 3 while flowing through the catalyst layer 2, the catalyst layer 2 is preheated to a predetermined temperature. 4 in the figure is a reactor for carrying out the method of the present invention, and the liquid oil that has reacted with the catalyst and hydrogen in the reactor 4 flows out from the extraction pipe 5 as a flow of oil with a smaller molecular weight and hydrogen.

The catalyst is supplied through a catalyst supply pipe 6, and extracted through a catalyst withdrawal pipe 7. In this case, the catalyst is removed from the reactor 4.
Since the structure does not have a dispensing device inside, the entire amount can be easily extracted without any difficulty.

Details of the raw material supply pipes 1 and 2 are shown in FIG.

Liquid oil is supplied from the supply pipe 1 and flows out from the nozzle 8 toward the bottom of the reactor 4, but this nozzle 8 is constricted at the outflow section, so that it constantly flows out into the reactor 4 at a certain flow rate. Ru. Therefore, the nozzle 8 is not clogged with catalyst particles. According to experiments conducted by the inventors, hydrogen supply amount/liquid supply amount (
-〇/L) is 2 to 3, making the effective cross-sectional area of the nozzle 8 1 to 2 times the cross-sectional area of the hydrogen supply pipe 2,
It was proven to give the most effective dispersion effect.

The hydrogen supply pipe 2 has a large number of hydrogen jet ports 9 at the bottom and the circumference of the hydrogen supply pipe 2, and is mixed with and dispersed with the liquid oil that flows out as a jet, and is supplied to the inside of the catalyst bed 3 where it is fluidized.

According to this experiment, when G/L is maintained at 2 to 3, considerable turbulent flow and mixing from the top to bottom pipes of the reactor 4 are obtained, and the minimum fluidization velocity Mar is set to the superficial velocity of hydrogen v9. It has been found that in many cases, temperature control means in the hydrogenation reactor are essentially unnecessary because the temperature can be maintained at the same level or higher. Instead of heat exchange and dispersion with the hydrocarbon oil and hydrogen, it is thought that the temperature is stabilized by equalizing the fluidization speed by using the double pipes 1 and 2 equipped with the nozzle opening 8 and the small opening 9. Furthermore, the temperature gradient within the reactor 4 that normally occurs is averaged out and substantially eliminated by the mixing from the top to the bottom.

Therefore, if the method of the present invention uses finer than usual substances, there will be no difficulty in maintaining the internal circulation flow (turbulent mixing between the top and bottom of the reactor), or the low temperature that is widely used to control the heat generated by the reaction. Eliminates the cost of hydrogen cooling methods.

In addition, according to the method of the present invention, a reactor without a distribution device can be used, so there is no cause for increased pressure loss due to clogging, and therefore it can be carried out with low pressure loss, and there is no increase in pressure loss over time. It has the advantage of not having

Figure 3.4.5 shows the results of hydrocracking of heavy hydrocarbon oil in Examples.

In this embodiment, a hydrogen supply pipe with a diameter of 20 marks and a nozzle tip 4 are used.
A N1-M alumina catalyst (Ni port: 3.4 wt%, M , oOa: 1
9.8 wt% Al2O3: balance) or Co-Mo-based alumina catalyst (CoO: 3.3 wt%, Mo a:
14wt%, ^1203: remainder) and hydrogen supply machine 2 m'/h (circulating hydrogen amount 40ff+3
7 hours ± 25%), shell oil supply amount 1 m3/h (circulating shell oil 20 m3/l + ± 25%), hydrogen and shell oil were supplied from the hydrogen supply pipe and liquid oil supply pipe, respectively.
The reaction was carried out under conditions of an average temperature of 380° C. (340° C. during the period of high initial catalytic activity, 420° C. during the period of lower catalytic activity at the later stage) and an average pressure of 150 kg/ad G.

Figure 3 shows the relationship between pressure drop and liquid superficial velocity when 1=1 (liquid oil and hydrogen) is supplied from the bottom of the reactor through the distribution device into the boiling bed as Comparative Example B. show. In both cases, when the amount of hydrogen is constant, as shown in the figure, the present example Δ is as low as about A, and in the conventional example B, as the liquid superficial velocity increases, it is 1. Therefore, the pressure loss tends to increase, but this tendency is not seen in this example.

This is a result of the pressure loss inherent to the distribution device, and it is clear that the above phenomenon does not occur at all in the case where the distribution device is not provided, as in this embodiment.

Figure 4 shows the change in pressure loss within the reactor over time. In the ebullated bed reactor of Conventional Example B, an increase in pressure loss was observed over time, but in this Example A, this tendency was not observed. I couldn't.

The results of the open inspection showed that in conventional models with a distribution device (dispersion plate), the distribution plate was partially clogged with catalyst powder (wear debris from mixing), which resulted in an increase in pressure loss. I can understand that there is.

Figure 5 shows the hydrocracking rate and G/L of Example A and Conventional Example B compared with CH2O (=supplied liquid oil amount/catalyst bed volume).
Shown under constant. As shown in the figure, when G/L is 1.5 or less, the decomposition rate of this example is lower than that of conventional example B, but this is because the amount of hydrogen is small and sufficient flow phenomenon cannot be obtained. This is also because, in accordance with the present invention, the hydrogen gas supply pipe 2 is located at the center of the reactor, resulting in partial flow. However, G/L which exhibits sufficient flow =
It can be seen that the hydrogenolysis rate remains almost unchanged for 15 to 3.

Next, a different embodiment of the hydrogen gas supply pipe 2 is shown in FIG.

Example (a) has numerous small-diameter jet ports 9-1 in order to enhance the dispersion effect of hydrogen gas.

The smaller the bubbles are, the larger the specific surface area relative to the amount of gas is, increasing the reaction efficiency, and according to experiments conducted by the present inventors, sufficient flow is provided. It has been proven that when G/L=2 to 3, the dispersion effect is almost the same compared to the conventional method having a distribution device.

In the example (b), the hydrogen gas ejection port 9-2 has a spiral shape as shown in its cross-sectional view (b'), and the ejection of hydrogen gas gives a rotating force to the catalyst layer. , G/L
This is effective in cases where the The experimental results showed that when G/L=1, the hydrogenolysis rate was higher than in Example (a). In addition, when G/L=2 to 3, which provides sufficient flow, a circulation pattern was formed in which the outside of the catalyst layer was an upward flow and the central part was a downward flow, and temperature control of the reactor was almost unnecessary.

Next, the overall flow when implementing the method of the present invention will be explained using FIG. The supplied liquid oil and hydrogen gas are injected into a reactor 4 filled with a fluidized catalyst 3 through a double pipe composed of a liquid oil supply pipe 1 and a hydrogen gas supply pipe 2, respectively, and the reaction rate is 50 kg/cdG to 300 kg within the reactor. /cjG,
Hydrocracking is carried out at 340° C. to 480° C., after which the gas-liquid mixture 5 is fed to a gas-liquid separator 10, which produces a gas product 12, a liquid product 13, a hydrogen recycle stream 14, and an external liquid. The hydrogen circulating flow 14 and the external liquid circulating flow 15 are separated into a circulating flow 15 and join the hydrogen supply pipe 2 and the liquid oil supply pipe 1, respectively. Further, the catalyst partially entrained in the vessel liquid mixture 5 is discharged from the solid content storage tank 11.

In the above example, a catalyst with an average particle size of 1.6 mm was described, but the same method as in the example can be applied to cases where the average particle size of the catalyst is small (approximately 0.3 mm) or large (5 ops). We confirmed that it was effective.

The active components of this catalyst include Co-Mo silica alumina, Ni1o silica alumina, and NiM.

P2O5--Vine using alumina.

As described above, the method of the present invention has low pressure drop, no increase in pressure loss over time, can use a structurally simple and compact reactor, and can obtain a high hydrogenolysis rate. This is a hydrocracking reaction method that easily eliminates the large heat generation and temperature gradient caused by the hydrogenation reaction, and is also a practically useful reaction method in that the catalyst can be removed very easily since there are no appendages at the bottom. I can say that.

Further, a double pipe integrally combining the liquid oil supply pipe 1 and the hydrogen supply pipe 2 is attached to the upper part of the reactor 4 used in the method of the present invention via a flange (not shown). Since the liquid oil is suspended inside the raw material supply pipe 1, if the properties or other conditions of the liquid oil change and it becomes necessary to change the jetting speed or direction of the liquid oil or hydrogen, the flange can be removed and the raw material supply pipe 1. 2 can be pulled out of the reactor 4 and the nozzle 8 or hydrogen gas outlet 9 can be easily replaced.

[Brief explanation of drawings]

Figure 1 is a longitudinal cross-sectional view showing an example of an apparatus for carrying out the method of the present invention, Figure 2 is an enlarged view of the raw material supply pipe section exhibiting a double pipe structure in Figure 1, and Figure 3 Figure, Figure 4, Figure 5
The figure is a graph showing the effects of the method of the present invention, Figure 6 is a side view and cross-sectional view showing another embodiment of the raw material supply pipe of the reactor used in the method of the present invention, and Figure 7 is a graph showing the effects of the method of the present invention. FIG. 2 is a flow diagram of an example method.

Claims (1)

[Claims] (1) When hydrogen is brought into contact with liquid oil through a catalyst under high temperature and high pressure to hydrocrack it, the average particle size is 0.2.
In a reactor filled with ~8 mm of catalyst, hydrocarbon oil is continuously supplied from the top of the outside and passed through the catalyst layer downward while exchanging heat with the catalyst in a non-contact state, and 1 of the hydrocarbon oil from the upper part of the outside.
．． After feeding 5 to 3 times the amount of hydrogen downward while exchanging heat with the hydrocarbon oil and the catalyst in a non-contact state, the hydrocarbon oil is jetted toward the center of the bottom of the reactor. Further, by dispersing and ejecting the hydrogen into the ejected hydrocarbon oil at a high speed, the granular catalyst, hydrocarbon oil, and hydrogen are stirred and mixed to achieve a 340 to 480
A method for hydrocracking hydrocarbon oil, characterized by carrying out liquid phase hydrogenation while boiling under predetermined substantially isothermal and isobaric conditions at 50 to 300 kg/cm^2G.