JPS61287438A - Dispersing device for three phase fluidized bed reactor - Google Patents

Abstract

PURPOSE:To improve dispersing performance and reaction efficiency of a three phase fluidized bed reactor providing plural gas introducing holes around the bottom of a dispersing cylinder, and providing simultaneously plural ejecting orifices around caps with a distance at an outlet at the top of the dispersing cylinder. CONSTITUTION:Plural gas introducing holes 15 are provided around the bottom of a dispersing cylinder 11 for passing gas liquid mixed phase stream (b, c) installed to penetrate through an attaching plate 2 at the bottom of a main body 1. Further, plural ejecting orifices 16 are provided around caps 12 provided with a distance to an outlet at the top of the dispersing cylinder 11. Therefore, introduction of gas from a mixing bed at the bottom of the attaching plates 12 into the dispersing cylinder 11 is controlled and variation of introduced amt. is reduced remarkably, and fluidization in a fluidized bed above the attaching plate 2 is stabilized due to reduction of variation of internal pressure. Furthermore, gas/liquid mixed phase stream introduced into the caps 12 from the dispersing cylinder 11 is dispersed and ejected from the ejecting orifices 16 to atomize the gas remarkably finely.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a gas/liquid multiphase flow dispersion device in a three-phase fluid reactor that simultaneously brings solids, liquids, and gases into contact with each other, converts them into fluidized forms, and reacts them. be.

(Prior Art) The three-phase fluidized reactor is known to be effective when the reaction that occurs is a significantly exothermic reaction because it has good contact efficiency between solid, liquid, and gas and is in a fluid state. For example, there are catalytic reactors such as hydrodesulfurization reactors, which supply hydrogen to heavy and medium oil fractions separated from crude oil in the presence of a catalyst, and hydrocracking reactors, which react with three-phase flow. A specific example of hydrodesulfurization of petroleum-based and medium oil fractions using a reactor is to desulfurize spherical nickel on a cylinder of 0.5 to 5 m + 1φ under conditions of a pressure of 50 to 150 kg/cIIL2G1 and a temperature of 350 to 420°C. a molybdenum-based, cobalt-molybdenum-based or tanksten-molinopone-based catalyst;
The hydrogenation reaction has been achieved by bringing the feed oil and gaseous hydrogen into contact in a three-phase fluidized bed.

The three-phase flow reactor is described in Sakae Tanaka, Chemical Engineering Vol. 34,
12 (1970) etc., the general flow state is described in detail, and solid particles such as catalyst packed in a vertical cylindrical container are at least 10
The liquid and gas are supplied from the lower part of the container and distributed in a dispersed manner so that the desired fluidization can be obtained by creating an expanded state that occupies a large volume of % or more, and the liquid and gas are supplied from the lower part of the container at a speed that does not raise the solid particles. By this, the solid particles can be made into a stable fluidized bed, and in order to continue the fluidization, liquid and gas are introduced and pumped from the upper side of the fluidized bed consisting of three phases of solid, liquid and gas. Circulating the inflowing liquid and gas by extracting them and supplying them to the lower part of the container is an essential element, ensuring the flow rate necessary for the flow of solid particles (catalyst) and contacting the solid, liquid, and gas. In order to increase efficiency, a dispersion device is installed at the bottom of the three-phase flow reactor to distribute and disperse the gas-liquid mixed phase flow of liquid and gas.

In the conventional three-phase flow reactor, as shown in FIG. 2) is provided with a plurality of dispersion devices (5), and the dispersion devices (5) convert the gas and liquid in the mixed layer at the bottom of the mounting plate (2) into a gas/liquid mixed phase flow (
b, c) to distribute and disperse the solids on the top of the mounting plate (2).
The fluidized bed (a) is made up of three phases of gas, and the liquid (A) extracted from the fluidized bed (α) is extracted from the circulation port (1h), and the gas <A> that is also extracted is transferred to the circulation port (1o). From the mounting plate (2
) has a structure in which it is circulated to the mixed layer at the bottom, and
The dispersion device (5) consists of a dispersion tube (5α) provided through the mounting plate (2), and a cap (5b) disposed at a distance above the dispersion tube (5α). , from the mixed layer at the bottom of the mounting plate (2), gas/liquid and phase flows (h, c) flow through the dispersion tube (5α), and flow from the outlet provided at the top of the dispersion tube (5α) to the mounting plate ( 2) The fluidized bed (a
), and the dispersing device (5)
The gas-liquid dispersion is carried out, and the dispersion and circulation within the fluidized bed (α) is promoted, the expansion state of the fluidized bed (α), that is, fluidization is ensured, and the contact efficiency of the three phases of solid, liquid, and gas is improved. The structure is such that the reaction is accelerated.

(Problems with the prior art) In the conventional dispersion device, the gas (bubbles) cannot be made sufficiently fine and the gas-liquid contact interface area per amount of gas supplied is small. It is necessary to supply more gas than necessary to dissolve the dispersion tube, which causes problems such as wasted gas and reduced reaction efficiency. There are problems with the blowing of gas into the reactor, such as fluctuations in the internal pressure, which can adversely affect the formation of a fluidized bed and the reaction.

(Objective of the Invention, Means for Solving Problems) The present invention was developed to solve the above-mentioned problems. In a dispersion device that circulates and disperses a multiphase flow, a plurality of gas inflow holes are provided around the lower part of a dispersion cylinder that is installed through a mounting plate at the lower part of the main body and through which the prerecorded liquid multiphase flow flows; The area around the lower part of the dispersion cylinder is characterized by a plurality of ejection holes arranged around a cap placed at intervals on the outflow part of the upper part of the dispersion cylinder, and is provided through the mounting plate. By providing multiple gas inflow holes in the dispersion tube, it is possible to control the speed of gas inflow into the dispersion tube, significantly reduce fluctuations in the amount of gas flowing into the dispersion tube, and stabilize the flow of the fluidized bed by reducing internal pressure fluctuations. By providing multiple ejection holes around the cap placed on the top of the cap, the gas is made finer and the gas-liquid contact area is increased, improving dispersion performance and reaction efficiency, and solving the above problems. The object of the present invention is to provide a dispersion device for a three-phase flow reactor.

(Example) Figure 1 shows an example of the present invention. In the figure, (2) is fixedly installed at the lower part of the three-phase fluid reactor body (1), and the inside of the body is connected to the upper and lower parts. A partitioned mounting plate, the mounting plate (
2) is equipped with a plurality of dispersion devices (1), and the dispersion device (10) converts the gas (C) and liquid (b) in the mixed layer at the bottom of the mounting plate (2) into a gas-liquid multiphase flow (b). , c) is distributed and distributed in the solid above the mounting plate (2), and a three-phase fluidized bed (α
).

To explain the dispersion device (lO) in more detail, there is a dispersion tube (11) provided through the mounting plate (2), and a dispersion tube (11) fitted at intervals on the top of the dispersion tube (11).
(13), and a plurality of outlets (14) are provided at the upper station H of the dispersion tube (11), and a plurality of outlets (14) are provided around the lower part of the dispersion tube (11). The gas inlet hole (15) of
The caps (
12) has a configuration in which a plurality of jet holes (16) are arranged around the lower part of the side surface, and the gas inflow holes 0ω are formed at several diameters and spaced apart in the circumferential direction and vertically spaced apart. In the mixing layer at the bottom of the mounting plate (2), the liquid (A) tends to separate into a liquid phase and a gas phase as shown in the figure, and the liquid (A) is disposed in the dispersion cylinder (11). The gas (C) flows in through the gas inlet hole (15) and the gas/liquid multiphase flow (
b, c) and flows upward in the dispersion tube (11), and the prerecorded liquid multiphase flow (, 6, c) flows through each outlet (
14) into the cap (12), is further ejected from each ejection hole (16), is dispersed, and is dispersed and supplied into the solid (catalyst), that is, the fluidized bed (α) on the upper part of the mounting plate (2), forming an upward flow. The structure is as follows.

Note that the liquid (b) mainly flows out from the lower edge of the cap (12) to the upper part of the mounting plate (2).

(Performance test) The inner diameter of the three-phase fluid reactor body (1) is 300 mm, the height is 3000 inches, the supplied liquid is white kerosene specified by JIS, the gas is nitrogen, the solid (catalyst) has an apparent specific gravity of 1.35, and a diameter 1,5
The related extrusion molded product was operated at room temperature and pressure, the superficial velocity of the gas was 4 cm/sθC, the amount of solid (catalyst) packed was 17001 m in a static state, and the liquid void Increase the column speed from 1 to 10 crfL/sθC
The conditions were as follows: four conventional dispersion devices (5) shown in Fig. 3 were arranged on the mounting plate (2) (the inner diameter of the dispersion cylinder (5α) was 20mm, the inner diameter of the cap (5h) was 30iii)
As a result of the test, many large bubbles exceeding several 1 ml were observed, and as shown in Fig. 2, a sulin (25) with a width of 3111 mm was provided at the bottom of the dispersion cylinder (11), and a sulin (25) was installed around the cap (12). As a result of testing by providing a dispersion slit (26) with a length of l Oxx1 and an interval of 3 mm, the amount of gas retained (gas hold up) was 14 to 16 mm O1%, and many large bubbles exceeding several sizes were observed. Ta.

On the other hand, as a result of testing the dispersion device (lO) of the present invention shown in FIG. 1 in the same arrangement and under the same conditions as the above test, the amount of gas retained was 20 Vol %, and bubbles with a diameter of several dragons or more were found. There were almost no bubbles, and the entire structure was occupied by fine bubbles, clearly improving the gas-liquid contact efficiency, which was even better than the reference example shown in FIG.

(Effects of the Invention) As described above, the present invention provides a dispersion device disposed at the lower part of the three-phase fluid reactor main body (1) for circulating and dispersing the gas/liquid multiphase flow (b, C). A plurality of gas inflow holes (1
5), and a plurality of ejection holes (]6) are arranged around the cap (12) arranged at intervals on the outflow part of the upper part of the dispersion cylinder (11), so that the installation is easy. The inflow of gas from the mixing layer at the bottom of the plate to the dispersion tube is controlled, and variations in the inflow amount are significantly reduced, internal pressure fluctuations are reduced, and the flow in the fluidized bed at the top of the mounting plate is stabilized. The gas-liquid mixed phase flow that circulated inside the cap is dispersed and ejected from the nozzle hole, making the gas significantly finer and significantly increasing the gas-liquid contact area, which saves gas and improves both dispersion performance and reaction performance. This has the effect of significantly improving performance and stabilizing operation.

Although the present invention has been described above with reference to embodiments, it goes without saying that the present invention is not limited to such embodiments, and that various design modifications can be made without departing from the spirit of the present invention. .

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a dispersion device showing an embodiment of the present invention;
FIG. 2 is a longitudinal sectional view showing a reference example, and FIG. 3 is a longitudinal sectional view of a three-phase fluidized reactor showing a conventional example. 3-phase flow reactor main body, 2: mounting plate, 11: dispersion cylinder, 1
2: Cap, 15: Gas inflow hole, 16: Outlet hole Multiple attorneys: Shige Okamoto, patent attorney, 2 other people

Claims (1)

[Claims] In a dispersion device disposed at the lower part of a three-phase fluid reactor main body for circulating and dispersing a gas/liquid multiphase flow, a dispersion device installed through a mounting plate at the lower part of the main body for distributing the gas/liquid multiphase flow. Along with providing multiple gas inflow holes around the bottom of the cylinder,
A dispersion device for a three-phase flow reactor, characterized in that a plurality of ejection holes are disposed around a cap disposed at intervals at an outflow portion of the upper part of the dispersion cylinder.