JPS61133136A - Reactor - Google Patents

Abstract

PURPOSE:To facilitate charge and discharge of catalyst by locating a porous central pipe at the center of a reactor and locating simultaneously a porous cylinder which is concentric with the central pipe and having a gas passage constituted between an external shell of the reactor. CONSTITUTION:Water contg. substantially no steam bubbles is introduced from a nozzle 13 and flows from below toward above through an annular space formed by the inside dia. of a cooling pipe 15 and an outside dia. of a central pipe 17. Steam is generated and moved upward from an inside surface of the pipe 15 serving as a heat transmitting surface. A fluid mixture consisting of water having risen to the top of the cooling pipe 15 and the steam is inversed its flow direction and flows downward through the central pipe 17 and discharged from a nozzle 14. Since in this reactor, a lower tube plate 7 is contained but no upper tube plate is contained, packing work of the catalyst is facilitated remarkably.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides a reactor in which hydrogen and carbon monoxide (and carbon dioxide) gases are used in a solid state such as a methanol base.

(Prior art) For this type of reactor, various methods and structures have been proposed to completely control the rise in gas temperature due to exothermic reactions during operation. As evidenced by the effect of temperature on the methanol equilibrium concentration of
This is because as the temperature rises, the methanol equilibrium concentration decreases, impairing the economic efficiency of industrial patents.

Even if a catalyst is used, the reaction rate is limited, and the reaction rate naturally decreases as the temperature decreases, so industrially it is necessary to operate within a certain appropriate temperature range that takes catalyst performance into consideration.

German Patent No. 3007203 is a well-known example of a reactor 1 structure with this precise temperature control. This known example is the seventh
As shown in the above, the cooling units 1iF (a plurality of units) 2 are vertically positioned and fixed by upper and lower tube plates 3, and the pressurized water at the total saturation temperature inside the tubes is moved from the bottom to the top. Also,
The space formed by the limb tube 2 and the shell 1 is filled with the catalyst 5 through the perforated plate 4, and the unreacted gas is caused to flow into the reactor from the upper part of the shell and move in the axial direction within the catalyst bed. Reaction-completed gas is taken out from the bottom of the shell.

When this known example is used industrially, filling the catalyst,
The major drawback is that it is difficult to extract. In other words, since multiple cooling pipes are installed, it is practically impossible to bring workers or tools inside the shell.
Due to insufficient catalyst filling, it is not possible to obtain satisfactory performance as a reactor.

(Problems to be Solved by the Invention) The present invention aims to solve the drawbacks of such known examples and provide a reactor that can be applied industrially.

[Means for solving problems]

That is, in the present invention, the gas to be reacted with the solid particulate catalyst is placed outside the tube to perform an exothermic reaction, and pressurized water with a saturation temperature lower than the gas temperature is placed inside the tube to reduce the heat of reaction by latent heat of vaporization. In the reactor, a porous central tube is located in the center of the reactor, and a gas flow path is provided concentrically with the central tube and between the outer shell of the reactor and the reactor. The configured porous cylinder is fully positioned, the annular space composed of the center tube and the cylinder is used as a catalyst filling part, and a removable cover plate is attached to the top of the catalyst filling part to fill the gas to be reacted. In order to allow the flow to flow in the annular catalyst packed bed in the radial direction, a cooling tube with a lid at the upper end is fixed vertically to the tube plate located below the reactor, and the cooling tube is centered at the center of the limb tube. This reactor is characterized in that the water rises through the annular space formed by the limb tubes and the central tube, and the gold vapor within the central tube descends.

A preferred embodiment of the present invention is to configure the above reactor as follows.

Cooling of the area where the gas and catalyst are located on the outer surface! The diameter of the tube should be larger than that of the tube plate insertion section.

A sectional view of the basic structure of the reactor of the present invention is shown in FIG. 1, and a radial plan view thereof is shown in FIG.

The symbols in FIGS. 1 and 2 mean the following.

1: Unreacted gas inlet nozzle, 2: Pressure-resistant shell (consisting of @! and cylinder), 44; Lid plate, 5: Center tube consisting of perforated plate,'
6: Cylinder made of perforated plate, 7.8; Tube plate, 9: Lid plate, 1
G, 11: Cylinder, 12: Cylinder, 13: Make-up water inlet nozzle, 14; Steam outlet nozzle, 15; Cooling pipe (plurality),
16: Lid (attached to tube 15 with a pan), 17: Center tube (tube 1
Everything in 5! i layer), 18; reaction completion gas outlet nozzle,
19: Solid particulate catalyst, 20: In the gas flow path shown in FIG. 1, the reaction heat is extracted to the outside of the reactor as the latent heat of evaporation of pressurized water at the saturation temperature located inside the cooling pipes 15 (multiple pipes). However, the present invention is characterized in that it employs a so-called bayonet type cooling pipe.

The water (substantially containing no water vapor bubbles) sent in from the nozzle 13 moves from bottom to top within the annular space formed by the inner diameter of the cooling pipe 150 and the outer diameter of the central pipe 17, and flows into the inner diameter of the pipe 15. The surface acts as a heat transfer surface, generating water vapor as it rises.

The mixed fluid of hole water and steam that rises to the top of the cooling pipe 15 has its flow direction reversed, flows down inside the pipe at the center IW 17 from top to bottom, and is discharged from the nozzle 14 .

As described above, in the reactor of the present invention, the lower tube sheet 7 is present, but the upper tube sheet is not present, and this has the advantage that the catalyst filling operation is considerably facilitated.

In the reactor of the present invention, a central tube 5 having a porous structure is further located in the center of the reactor, and a cylinder 6t having a porous structure is located at a position holding a gas flow path 20t from the reactor shell (outer shell) 2. - to position. Lid 3t when filling catalyst
-Remove the center tube 5, cylinder 6 and cooling tubes 15 (multiple pieces)
The catalyst bed 19 can be easily formed by dropping the granular solid catalyst from above into the space formed by the above structure. (In Fig. 2, the center pipe 17 is not shown.) When removing the catalyst, as shown in Fig. 3, the lower part of the center pipe 5 (indicated by the dotted line, this part is the bolt assembly) is disassembled and the solid is removed. It is possible to extract the granular catalyst by letting it fall downward by gravity, or it is also possible to remove the cover plate 3 and connect a catalyst extraction tool to a vacuum pump via a tube to extract it.

Since the reactor of the present invention does not have an upper tube plate, it is easy to position all workers and tools above the lid plate 3 to carry out catalyst filling and removal operations, which is the first feature of the present invention. It is.

Next, the second feature of the reactor of the present invention is that the gas to be reacted is made to flow in the radial direction of the reactor. 1st
In the figure, unreacted gas is introduced from nozzle 1;
After flowing into the center pipe 5, it flows into the catalyst bed 19 through the pores of the center VS and moves in the radial direction, causing a contact reaction.
By giving the reaction heat to the water in the cooling pipe 15 through the pipe wall of the cooling pipe 15 (multiple pieces), the gas temperature is maintained within the appropriate condition range and flows out from the porous part of the cylinder 6 to the gas flow path 20. Then, it is taken out from the reactor through the nozzle 18. Naturally, the center tube 5 and the cylinder 6 should be concentric circles to equalize the gas flow resistance of the catalyst bed 19 and to equalize the space velocity.

As shown in FIG. In the present invention, the diameter, height, and length of the reactor are not particularly restricted, or the known example (Fig. 7) In this case, the gold gas in the catalyst bed flows in the axial direction, but the gas flow path area is small (g! velocity is large), and the pressure loss (differential pressure) as a reactor is large. There is. On the other hand, in the present invention, since the gold gas within the catalyst bed is made to flow in the radial direction, the area of the gas flow path can naturally be increased. Although this gas passage area changes in the radial direction, the minimum passage area can be freely adjusted by changing the diameter of the central tube 5. In any case, in the present invention, the catalyst bed thickness is as small as less than 7 the diameter of the reactor, and the space velocity of the ninth gas, which has a large average gas flow area, is kept small, and the contact time is kept under appropriate conditions. This means that the gas flow resistance (differential pressure, pressure loss) in the reactor is reduced,
It has great industrial value in that it can reduce the driving energy of the circulating gas compressor.

On the other hand, when the contact speed is reduced, the amount of reaction per unit space naturally increases, and it is important to effectively remove the corresponding heat generated in order to maintain the reaction temperature within the appropriate condition range. However, in the present invention, the inventors have already proposed as Japanese Patent Application No. 1750.95/1982.
As shown in FIG. 5, compared to the tube diameter (1,
By making e large, the heat transfer area of the cooling pipe 15 can be freely increased and adjusted.

It is natural that the heat transfer area (pipe length x pipe length) is proportional to the pipe diameter, but increasing the pipe diameter at the tube sheet insertion part is constrained by the structural mechanics of the tube sheet, and the inventors The pipe diameter of the tube plate insertion part is required to make it possible to insert the center pipe (its outer diameter aS) at its inner diameter d2 and to secure a water flow path consisting of the inner diameter am and the center pipe outer diameter d3. The pipe diameter of the region simulating the catalyst and gas is set to d1≧d2, and the pipe diameter is freely adjusted without any upper limit. Naturally, the diameter of the pipe in the region in contact with the catalyst and gas can be made to vary in the radial and longitudinal directions of the reactor. Naturally, increasing the diameter of the cooling pipe in the same space reduces the remaining space area, resulting in a decrease in the amount of catalyst packed and an increase in the space velocity, but these are related to the amount of heat generated, and under appropriate conditions. This can be handled by setting the diameter of the cooling pipe.

9. When unreacted gas (methanol concentration is essentially zero) comes into contact with the catalyst, the reaction proceeds at a much higher reaction rate (exothermic rate) with a large difference from the reaction equilibrium concentration, and the methanol concentration in the gas decreases. Nine, the reaction rate decreases as the value increases.
Using the reactor of the present invention, unreacted gas with a low methanol concentration in the gas is supplied to the center tube 5 in FIG. The heat load on the reaction tubes 15 can be equalized by increasing the space velocity during the reaction period and decreasing the space velocity during the latter stages of the reaction, and further by changing the diameter of the cooling tube 15 described above. Furthermore, it is possible to carry out an isothermal reaction that is significantly superior to conventionally known techniques.

In addition, as an industrial application form of the reactor of the present invention, the present inventors have proposed a downstream reactor in Japanese Patent Application No. 59-144162 and Japanese Patent Application No. 59-180727. Applying the invented reactor also has a great effect. That is,
Water at saturated temperature in the cooling tube as in the reactor of the present invention,
In the nine reactors in which a granular catalyst and gas are placed outside the tube, unreacted gas (methanol concentration is essentially zero) comes into contact with the catalyst and reacts at a high reaction rate (heat generation rate). Heat generation at the initial stage of the reaction. The cooling capacity of the cooling pipe is often small compared to the speed (insufficient heat transfer area), and one countermeasure is to increase the diameter of the cooling pipe in the reactor of the present invention, but the above-mentioned existing proposal As mentioned in t, in the late stage of the reaction, the reaction product concentration increases and the difference from the equilibrium concentration of the reduced reaction is not large, so the reaction rate decreases, and the heat transfer area of the cooling tube does not need to be large. do not have.

Therefore, it is of great industrial value to apply the reactor of the present invention to the downstream reactor.

As described above, the present invention relates to a reactor that has advantages such as ease of loading and unloading of catalyst, and is an isothermal reactor with a built-in heat exchanger that brings gas into contact with a granular catalyst to perform an exothermic reaction such as methanol synthesis. It has great value when applied industrially as a type reactor, and its use is not limited to methanol synthesis, but can be applied to a wide range of uses.

(diameter, height and length of the reactor), gas pressure.

Specific specifications such as composition, diameter of cooling pipes, number of pipes, etc. are not particularly restricted as they vary depending on the application.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of the reactor of the present invention, FIG. 2 is a radial plan view of the same device, FIG. 5 is a diagram showing an example of the structure of the lower part of the center column, and FIG. 4 is a diagram of the present invention. An explanatory diagram of another mode of use of the reactor, Figure 5 is a schematic diagram explaining a cooling pipe that is advantageous when applied to the reactor of the present invention, and Figure 6 shows the relationship between pressure and temperature for methanol equilibrium concentration. The graph and FIG. 7 are cross-sectional views of a conventional reactor of this type. Subagent 1) Clearance agent Ryo Hagiwara - f Bundle reaction gas ↓ The reaction ends at Figure 5 Pressure (6Ltyn)

Claims (2)

[Claims] (1) By placing the gas to be reacted with the solid particulate catalyst outside the tube to cause an exothermic reaction, and by placing pressurized water with a saturation temperature lower than the gas temperature inside the tube to remove the reaction heat using the latent heat of vaporization. In a reactor designed to control gas temperature, a porous central tube is located in the center of the reactor, and a porous hole is formed concentrically with the central tube and forms a gas flow path between the reactor outer shell and the reactor. A cylinder is positioned, and an annular space constituted by the central pipe and the cylinder is used as a catalyst filling part,
A removable cover plate is attached to the upper part of the catalyst filling part to allow the gas to be reacted to flow in the radial direction inside the annular catalyst packed bed, and the upper end is attached to the tube plate located below the reactor. A cooling tube with a lid is fixed in a vertical direction, and a center tube is positioned in the center of the tube so that water rises through the annular space formed by the tube and the center tube, and water vapor descends inside the center tube. A reactor characterized by: (2) The reactor according to claim (1), wherein the diameter of the cooling pipe in the area where the gas and catalyst are located on the outer surface is larger than the diameter of the tube plate insertion part.