JPS6393344A - Boiling bed type reactor - Google Patents

Abstract

PURPOSE:To uniformize the flow of gas to a large number of gas-liquid dispersing devices, by placing the recirculation pump of the liquid in a cylindrical body outside said cylindrical body and forming a recirculation liquid discharge port and a recirculation liquid supply port into a concentric circular double pipe structure at the central part of the lower part of the cylindrical body. CONSTITUTION:A gas-liquid dispersing plate equipped with a large number of gas-liquid dispersing devices 9 and a recirculation liquid take-out pipe 5 are provided in the cylindrical body 1 being the main body of a reactor. A recirculation pump 6 is placed outside the cylindrical body 1 and a recirculation liquid is uniformly supplied to the liquid phase part (b) in a plenum chamber from a recirculation liquid take-out pipe 5 and a recirculation liquid supply pipe 7, both of which form a concentric circular double pipe structure (5 is set to an inner pipe) at the central bottom part of the cylindrical body 1, in an axially symmetric manner. A treatment liquid is supplied to the plenum chamber along with the recirculation liquid through the recirculation liquid supply pipe 7. By this method, the liquids can be almost uniformly supplied to the plenum chamber and the variation of the gas-liquid interface being formed can be reduced.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to hydrogenation of petroleum-based heavy oil, hydrocracking treatment reactor, upgrading treatment reactor of Sierra oil, coal liquefaction reactor, etc. This invention relates to an ebullated bed reactor in which three phases of gas, liquid, and solid flow.

[Conventional technology]

In a conventional three-phase gas-liquid-solid ebullated bed reactor, as shown in FIG. A treatment liquid and gas are supplied to flow the solid catalyst packed on the gas-liquid dispersion plate B to form a gas-solid-liquid three-phase fluidized bed a. In this case, since a large amount of fluidizing liquid is required, the internal liquid is taken out by a circulating liquid take-off pipe 5 and a circulation pump 6 and is circulated through a circulating liquid supply pipe 7 to the plenum chamber b. Processing liquid and gas are supplied through supply holes 2, processing liquid 12 is taken out through discharge holes 5, and processing gas 11 is taken out through discharge holes 4. The processing liquid 12 and gas 11 can also be taken out together from 4 without forming a special gas phase portion C. In the three-layer fluidized bed a, a treatment liquid (for example, heavy oil) and a gas (for example, horse gas) are brought into contact with a solid catalyst (for example, a hydrogenation catalyst) to undergo hydrogenation and hydrocracking treatment. (This example is described in Japanese Patent Publication No. 45-25721.) In the ebullating bed reactor shown in Fig. 3, the pump 6 is installed externally, and the circulating fluid supply pipe 5 are arranged asymmetrically in the plenum chamber, and the gas is supplied into the liquid in the plenum chamber, so the gas blow-through K
Since the gas-liquid passes through some of the gas-liquid distributors 9, the distribution of the gas-liquid is non-uniform, and the gas-liquid is not uniformly supplied to each of the many gas-liquid distributors 9.

[Problem that the invention seeks to solve]

In the conventional device, sufficient consideration is not given to the supply of gas. For example, in the example shown in Fig. 3, the plenum chamber 1
The gas supplied to is concentrated only in the part directly above the supply hole 2,
Since it is not uniformly dispersed in the cross section of the cylinder, the three-phase fluidized bed that is formed becomes non-uniform, resulting in lower contact efficiency and undesirable catalytic reaction and non-uniform bed temperature. In order to form a uniform gas-solid-liquid three-phase fluidized bed, it is necessary to distribute the gas and liquid uniformly over the entire cross section of the cylinder.

[Means for solving problems]

The present invention provides a gas-liquid-solid three-phase boiling bed reactor that can meet the above-mentioned demands. In an ebullating bed reactor that forms a gas-liquid-solid three-phase fluidized contact layer by flowing upward and flowing the solid catalyst packed on the dispersion plate, a circulation pump for the liquid inside the cylinder is used. is placed outside the cylinder, and the circulating liquid discharge hole and the supply hole have a concentric double pipe structure in the center of the lower part of the cylinder, and one gas is placed in a gas-liquid distributor at a certain distance directly below the gas-liquid distribution plate. This is an ebullated bed reactor characterized in that the gas is supplied to the gas phase formed by providing a gas introduction section.

In other words, the present invention improves the structure of the gas-liquid distributor to form a gas phase immediately below the distribution plate in the plenum chamber, in order to distribute gas and liquid uniformly over the entire cross section of the cylindrical body. In addition to supplying gas to the phase part, liquid is supplied to the liquid phase part as uniformly as possible over the entire cross section of the cylindrical body, with the supply of circulating fluid being axially symmetrical, so as to reduce fluctuations at the interface with the gas phase part. A boiling bed type that distributes gas and liquid uniformly through a large number of gas-liquid dispersers to form a stable and uniform gas-liquid-solid three-phase fluidized bed (boiling bed). It is a reactor.

In FIG. 1, a large number of gas-liquid distribution plates 8 with gas-liquid distributors 9 and a circulating liquid extraction pipe 5 are provided inside a cylindrical body 1 serving as the main body of the reactor. The circulation pump 6 is placed outside the cylindrical body 1, and the circulating fluid is supplied by a circulating fluid supply pipe 7 (5 is an inner pipe) which has a double pipe structure concentric with the circulating fluid take-off pipe 5 at the center of the bottom of the cylindrical body 1. As a result, the liquid phase within the plenum chamber is uniformly and axially symmetrically supplied. The processing liquid 12 is supplied to the plenum chamber together with the circulating liquid through the circulating liquid supply pipe 7.

In order to uniformly supply gas and liquid to the ebullated bed reactor, in the present invention, it is necessary to stabilize the gas-liquid interface formed in the plenum chamber as uniformly as possible. To achieve this, 1) placing the circulation pump externally and 2) making the supply of circulating fluid axially symmetrical allows the liquid to be uniformly supplied into the plenum chamber, thereby reducing the gas-liquid interface that is formed. It is possible to reduce the fluctuation of .

Furthermore, by making the structure of the gas-liquid distributor 9 specific, the gas-liquid can be uniformly supplied to the gas-liquid distributor 9.

The structure of the gas-liquid disperser 9 will be explained with reference to FIG. A single tube with a large number of sulins)e at the lower end as shown in Figure 2? In particular, when the gas-liquid distributor 9 consisting of a cap 9a having a large number of slits d at the lower end is attached to the gas-liquid distribution plate 8 in the same manner as in b, a gas phase portion C is formed directly below the gas-liquid distribution plate 8. , forming an air-liquid interface within the plenum chamber.

The gas-liquid interface within the plenum chamber is determined by the pressure and flow rate of the supplied gas and liquid, and the opening area of the slit e.

By keeping the positions of the slits of the large number of gas-liquid distributors 9 at a constant distance from the distribution plate, gas-liquid can be evenly supplied to each distributor 9.

That is, the liquid mainly enters through the lower part of the single tube 91 with the sleeve (e), and the gas enters the slit Qυ of the single tube 9b, and enters the cap 9a with the slit a as a gas-liquid multiphase flow. These gases and liquids enter the cylindrical body 1 through the slit d of the cap 9a, but the gas mainly enters the slit and the upper part, and the liquid enters the fluidized bed alc from the lower part. The sleeve a is designed to have a sufficiently small opening area to increase the flow rate of the gas and liquid, and is designed to achieve finer dispersion of the gas into the liquid.

The single pipe 9b is a gas/liquid introduction pipe, and the cap 9a has the function of finely dispersing the introduced gas/liquid into the liquid to supply the fluidized bed aK, and when the fluidized bed is operated or stopped. It has the function of preventing solids such as a catalyst from entering the grenum damper through the single pipe 9b, and the gas-liquid disperser 9 is formed by pairing the pipes 9b and 9a.

By supplying OK gas to this gas phase through the gas supply hole 2 of the cylinder 1 having the gas-liquid distributor 9 having the above-described structure, the liquid level fluctuation in the liquid phase in the plenum chamber will be minimized and each gas-liquid will be dispersed. Gas is uniformly supplied to the container 9. As a result, the gas-liquid/solid three-phase fluidized bed a that is formed exhibits a stable boiling bed state.

The treated liquid may be taken out from the clarified layer d which does not contain solids, and the gas and liquid may be separated in the cylinder 1 as shown in FIG. Takeout hole 5 as shown
It may be taken out as a mixture 15 of gas and liquid, separated into gas 14 and liquid 15 by the gas-liquid separator 4, and then taken out.

〔Effect of the invention〕

In the present invention, since the circulation pump is placed externally and the supply of circulating fluid is axially symmetrical, there is a
It is possible to supply the liquid uniformly, and in addition to the above, if the gas introduction part of the gas-liquid distributor is installed at a certain distance directly below the gas-liquid distribution plate, the gas that is formed can be By supplying gas to the phase, the gas-liquid-solid boiling bed is uniformly stabilized, but there is a possibility of problems such as an excessive rise in reaction temperature and reaction clouding. It is possible to completely eliminate the problem.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an embodiment of the ebullated bed reactor of the present invention, and FIG. 2 is a detailed diagram of the gas-liquid disperser of FIG. 1. Section S is a schematic diagram of a conventional ebullated bed reactor. Sub-Agents 1) Meifuku Agent Ryo Hagiwara - Sub-Agent Atsuo Anzai Figure 3

Claims (1)

[Claims] A large number of gas-liquid dispersion plates with gas-liquid distributors are installed in the vertical cylinder to allow gas and liquid to flow upward, and by flowing the solid catalyst packed on the dispersion plates, the three-phase gas-liquid-solid In an ebullated bed reactor for forming a fluidized contact bed, the circulation pump for the liquid inside the cylinder is placed outside the cylinder, and the circulating liquid discharge hole and supply hole are arranged in a concentric double pipe structure at the center of the lower part of the cylinder. , a boiling bed type characterized in that the gas is supplied to a gas phase portion formed by providing a gas introduction portion of a gas-liquid distributor at a certain distance directly below the gas-liquid distribution plate. reactor.