JP2001194089A - Vessel provided with heat-exchange function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a vessel provided with a heat-exchange function of a high heat-exchange efficiency between a reaction gas in a contact tube and a heat exchange medium by making small a flow deviation in the radial direction on a baffle for the flow in the vessel. SOLUTION: The vessel is provided with two kinds of baffles (baffle-1 and abaffle-2) in a vertical nearly cylindrical vessel. Each baffle has annular clearance alternately along the radial direction, the fluid in the vessel flows alternately inside and outside in the radial direction, in the reverse direction to each other with the clearance as the boundary.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container having a heat exchange function. More specifically, the present invention relates to a container having a heat exchange function capable of realizing high heat exchange efficiency between a reaction gas in a contact tube and a heat exchange medium by reducing a radial knitting flow of a fluid in a container on a baffle plate. It is.

[0002]

2. Description of the Related Art A heat exchange function having two types of baffles (baffle-1 and baffle-2) in a vertically installed substantially cylindrical vessel is known. However, the conventional type has two types of baffles, one of which is a so-called donut shape having a hole through which a heat exchange medium passes in the center of the disk, and the other is between the outside of the disk and the body of the reactor. It had a so-called disk shape with a gap. The radial flow velocity between the two types of baffles is inversely proportional to the radius unless there is leakage at the baffles. Therefore, when the body diameter of the reactor becomes large, the flow velocity in the central portion of the radial flow and the flow velocity in the body side are significantly different, and consequently there is a large difference in heat exchange efficiency. In addition, the flow velocity in the center becomes high and the flow becomes unstable. Due to these factors, the conventional one is insufficient from the viewpoint of realizing a sufficiently high heat exchange function.

[0003]

In such a situation,
A problem to be solved by the present invention is a container having a heat exchange function capable of realizing high heat exchange efficiency between a reaction gas in a contact tube and a heat exchange medium by reducing a radial knitting flow of a fluid in a container on a baffle plate. The point is to provide.

[0004]

That is, the present invention provides two kinds of baffles (baffles) in a vertically installed substantially cylindrical container.
le-1 and baffle-2), each baffle has an annular gap alternately along the radial direction, and the fluid in the container is separated from the radially inner and radially outer sides by the gap. And a container having a heat exchange function flowing in the opposite direction.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The container of the present invention has a heat exchange function capable of realizing high heat exchange efficiency between a reaction gas in a contact tube and a heat exchange medium by reducing a radial knitting flow of a fluid in a container on a baffle plate. It is a container which has. Further, the container of the present invention is a reactor for removing or absorbing heat of a multitubular reactor by a radial flow of a heat exchange medium, and is a reactor for performing an exothermic or endothermic chemical reaction. .
An upright contact tube bundle is provided in the apparatus. The contact tubes are filled with catalyst masses, above and below which are tightly attached to the cap of the vessel, through which the reaction gas flows through the contact tubes. Further, the heat exchange medium passes through the chamber of the vessel surrounding the contact tube and is adapted to absorb or supplement the heat released or used depending on the type of chemical treatment. After leaving the vessel, the heat exchange medium is brought to its original temperature through a cooling or heating device and recirculated into the vessel. In order to increase the efficiency of heat exchange between the reaction gas in the contact tube and the heat exchange medium, two kinds of annular baffles are alternately arranged so as to cause a radial flow.

In the prior art, the two types of baffles are so-called donut-shaped ones having a hole through which a heat exchange medium passes in the center of the disk, and the other is between the outside of the disk and the body of the reactor. It had a so-called disk shape with a gap. The radial flow velocity between the two types of baffles is inversely proportional to the radius unless there is leakage at the baffles. Therefore, when the body diameter of the reactor becomes large, the flow velocity in the central portion of the radial flow and the flow velocity in the body side are significantly different, and consequently there is a large difference in heat exchange efficiency. In addition, the flow velocity in the center becomes high and the flow becomes unstable. The present invention relates to a fixing column for fixing the central portion of a reactor and two kinds of baffles alternately arranged to reduce the radial knitting flow.

Hereinafter, description will be made with reference to FIGS. 1 and 2. One baffle (hereinafter referred to as baffle-1) covers from the center fixed column to the inside diameter of the body, and has an annular gap in the middle as a heat exchange medium passage port. The flow direction of the heat exchange medium between the radially inner side and the radially outer side becomes opposite to the gap. Other baffles (hereafter
baffle-2) has an annular gap between the center fixed column and the body as a heat exchange medium passage.

The determination of the diameter of the central fixed column, the position of the gap of baffle-1, and the size of the central fixed column side and trunk side gap of baffle-2 (these are referred to as design variables) are as follows. . From the center fixed column side of baffle-2 as radial flow ba
The radial knitting flow between the ffle-1 gap positions and the knitting flow between the baffle-2 waist side gap positions from the baffle-1 gap are minimized. ba
The differential pressure between the center fixed column side gap of ffle-2 and the gap position of baffle-1 is set so that the differential pressure between the body side gap position of baffle-2 and the gap position of baffle-1 is equal. Therefore, these design variables are not determined independently of each other, but may be dependent on these conditions. For example, baffle
Given the size of the fixed column gap at the center of -2 and the maximum allowable knitting flow ratio, the size of the trunk-side gap of baffle-2, which is another design variable,
The gap position of baffle-1 and the diameter of the central fixed column are determined dependently. Therefore, the diameter of the center fixed column may be 0, that is, there may be no fixed column as a result. The vertical axis at the left end of FIG. 2 indicates the central axis of the reactor, from which the radius R _C is the radius of the central fixed column, the radius r ₁ is the central position of the gap of baffle-1, and the radius R _S is the body. The radius is shown. Δr ₀ is baff
The size of the gap on the fixed column side of the center of le-2, Δr ₂ is baffle-2
Shows the size of the trunk-side gap. The size of the gap of baffle-1 is determined from the overall circulation flow rate and differential pressure.

FIG. 3 shows an example of a specific pattern of the flow velocity of the radial flow. u _max and u _min indicate the maximum value and the minimum value of the flow velocity, respectively.

FIG. 4 shows that the squared value of the flow velocity in the radial direction is proportional to the differential pressure, and the squared value of the axial flow velocity on the fixed column side and the body side of the baffle-2 is proportional to the differential pressure. The calculation example when the proportional constants are the same is shown.

As described above, the most significant feature of the present invention is that two kinds of baffle plates are alternately provided with an annular gap in the radial direction, and the direction of flow between the radially inner side and the radially outer side is defined by the gap. To reduce the drift by reversing

What has been described so far is, in other words, that the radial flow field has been split into two and that there is no need to partition the two flow fields with a pressure balance. . Thus, this idea can be extended to further split the radial flow field.

FIG. 5 shows a case where the radial flow field is divided into three parts, which will be described hereinafter with reference to this figure. Similar to the above, the two types of baffles will be referred to as baffle-1 and baffle-2. The baffle-1 has an annular gap between itself and the body, and an annular gap in the middle, which serves as a passage for the heat exchange medium. baffle-2 has an annular gap between the center fixed column and an annular gap at an intermediate radial position between the middle annular position of baffle-1 and the gap position of the inside diameter of the trunk. . The vertical axis at the left end of FIG. 5 indicates the central axis of the apparatus as in FIG. 2, and R _C and R _S indicate the radius of the central fixed column and the radius of the trunk, respectively. r ₁ is the middle annular gap position of baffle-1, r ₂ is baffle-2
3 shows the middle annular gap position. Δr ₀ is the size of the gap between baffle-2 and the central fixed column, Δr ₁ is the size of the intermediate gap of baffle-1, Δr ₂ is the size of the intermediate annular gap of baffle-2, Δ
r ₃ indicates the size between baffle-1 and the inside diameter gap of the trunk. Also in this case, between the center fixed column side and the middle gap position of baffle-1, ba
The radial flow between the middle gap position of ffle-1 and the middle gap position of baffle-2, and the radial flow between the middle gap position of baffle-2 and the gap position of the inside diameter of the trunk are respectively reversed. For that purpose, the differential pressure of each flow field is set to be equal, and the gap positions r ₁ and r ₂ , the gap sizes Δr _{0 ,} Δr _{1 ,} Δr ₂ , Δr ₃ and the center are set so that the drift is minimized. Determine the radius _{RC of the} fixed column.

FIG. 6 shows an example of a specific pattern of the flow velocity of the radial flow.

As described above, it has been shown that the radial drift can be reduced by providing more gaps in the baffle plate. However, at each gap position, the heat exchange medium passes in the axial direction, so that the flow in the radial direction is impaired. Therefore, it is natural that the intermediate gap between the baffle plates is reduced as much as possible within the allowable size of the drift.

[0016]

As described above, according to the present invention, by reducing the radial knitting flow of the fluid in the container on the baffle plate, a high heat exchange efficiency between the reaction gas in the contact tube and the heat exchange medium can be realized. A container having a function can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic example of the structure of a container. In the example of this figure, the baffles at the upper and lower ends are made of baffle-1. Thus, the heat exchange medium enters the vessel through two inlets, the outer annular conduit and the inner annular conduit, and exits through the outer annular conduit and the inner annular conduit, the outlets. Conversely, if the upper and lower baffles are baffle-2, the entrance and exit will be annular conduits of the same radius as the middle annular gap of baffle-1 in the upper and lower caps.

FIG. 2 is a diagram illustrating an example of a state of a fluid flowing on a baffle plate.

FIG. 3 is a diagram showing an example of a distribution of a flow velocity of a fluid flowing on a baffle plate.

FIG. 4 shows the maximum knitting flow ratio (u _max / u) of the fluid flowing on the baffle plate.
_min) and [Delta] r ₀ / R _{If S} has a varied, illustrates the calculated values and the result of which is another design variables _{Δr 2 / R S, R C} / R S and r ₁ / R _S. The left end of the figure is the center axis of the container, and the right end is the inside diameter of the body, which shows the shape of the center fixed column radius, baffle-1, baffle-2

FIG. 5 is a diagram illustrating an example of a distribution of a flow velocity of a fluid when a flow field is divided into three.

FIG. 6 is a diagram illustrating an example of a knitting flow ratio of a fluid flowing on a baffle plate.

[Explanation of symbols]

 R_C： Radius of fixed column at center  R_S： Body radius r₁, R_Two: Position of the gap between the baffles Δr₀, Δr₁, Δr_Two, Δr_Three: The size of the gap between the baffles u_max, U_min： Maximum and minimum flow velocity

Claims (1)

[Claims] 1. A baffle (baffle-1 and baffle-2) in a substantially cylindrical container installed vertically, and each baffle has an annular gap alternately along a radial direction. A container having a heat exchange function in which the fluid in the container flows in opposite directions radially inward and radially outward with the gap as a boundary.