JPS5915791A - Heat exchanger with fluidized layer - Google Patents

Abstract

PURPOSE:To enable to prevent scattering of particles coming out of a fluidized layer, to reduce the height of a hollow column section and to raise the efficiency of heat transfer by recovering heat possessed by a fluid efficiently. CONSTITUTION:In a fluidized heat exchanger having a heat exchanger tube 7 extended in a fluidized layer 5 and a hollow column section 6, fins 10 are attached to the heat exchanger tube 7 at the portion thereof located at the hollow column section 6. These fins 10 are attached to the tube 7 such that the fin portions held in contact with the heat exchanger tube 7 are perpendicular to the axis of the tube 7, opposite end portions of the fins 10 are inclined in the same direction, and adjacent fins 10 are located in parallel with the direction of the ascending flow of a high-temperature fluid.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a fluidized bed heat exchanger in which heat exchanger tubes are disposed within a fluidized bed in which a large number of particles are accumulated.

[Technical background of the invention and its problems] Generally, in the fluidized bed heat exchanger as described above, when the fluid flow rate exceeds the velocity at which the particles flow together (flow start velocity), the particles begin to move and the particle bed becomes stationary. Start flowing from. In this state, the fluid that has passed all the way through the dispersion plate provided at the bottom of the fluidized bed is moving the particles by rising and coalescing within the layer, and at the bed surface, there are no paths caused by the particles. As the resistance disappears and the pressure suddenly decreases, when this fluid is a gas, violent bursting of bubbles occurs, and this bursting causes particles on the surface of the layer to fly high out of the layer. Furthermore, when the fluid is a liquid, particles may be carried out of the layer with the flow.

Furthermore, in a fluidized bed, the particles are packed in an orderly manner, but the particles move due to the fluid overload. 1. The fluid moves out of the space that has reached b, filling it with fluid and increasing the volume of the fluidized bed.

1~ Therefore, in order to prevent particles from scattering from the increased fluidized bed as described above, the height of the empty column formed in the negative part of the fluidized bed should be set to the height reached by the above-mentioned flying particles. Therefore, there are problems such as an increase in the height of the device. In addition, in order to prevent particles from scattering outside the layer, some devices use a wire mesh with smaller openings than the particle diameter. There are disadvantages such as reducing the actual passage area, increasing passage resistance, increasing the power required to transport the high-temperature fluid, and in severe cases, causing a blockage state and significantly reducing the performance as a 1-1 heat exchanger.

[Purpose of the invention]

In view of these points, the present invention can prevent particles flying out of the bed from scattering, significantly reduce the height of the empty column, and can sufficiently recover the heat of the fluid for heat exchange. It is an object of the present invention to provide a fluidized bed heat exchanger that can improve efficiency and can sufficiently fix (join) fins and heat exchanger tubes.

[Summary of the Invention] The present invention provides a fluidized bed heat exchanger in which heat transfer tubes are provided in the fluidized bed and in the hollow column, in which fins are provided on the heat transfer tubes arranged in the hollow column, and the fins are connected to a high temperature fluid. The fins are inclined with respect to the upward flow direction and are arranged so that parts of the fins adjacent to each other are positioned in front and back relative to the upward flow direction of the fluid to prevent particles flying out of the layer from scattering,
The height of the empty column is significantly reduced.The part where the fins contact the heat exchanger tubes is perpendicular to the heat exchanger tubes, and the fixation (joint) between the fins and the heat exchanger tubes is completely ensured. shall be.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to FIGS.

In FIG. 1, reference numeral 1 denotes a casing of a heat exchanger, and one end of the casing 1 is provided with an inlet 2 through which high-temperature fluid A is introduced, and the other end is provided with an inlet 2 through which high-temperature fluid A is discharged. An exit 3 is provided. On the side of the inlet 2 in the casing 1, there is a dispersion plate 4 for uniformly distributing the high temperature fluid.
A large number of particles are accumulated on the dispersion plate 4 to form a particle layer 5, and a hollow column 6 is formed above the particle layer 5.

Incidentally, a meandering heat transfer tube 7 is disposed in the particle layer 5 and the empty tower section 6 in which the particles are accumulated, and the empty tower is provided at the outer end of the casing 1 on the outlet 3 side. A heat exchanger tube 8 is installed which is connected to the heat exchanger tube 7a located in the part 6 and introduces the fluid B to be heated into the heat exchanger tube 7, and furthermore, the outer part of the casing 1 on the inlet 2 side is provided with a A heat exchanger tube outlet 9 is provided which is connected to the heat exchanger tube 7b disposed in the heat exchanger tube 7b. Further, at least the uppermost heat exchanger tube of the heat exchanger tubes 7a disposed in the hollow tower section 6 is provided with fins 10 that are inclined with respect to the flow direction of the high temperature fluid supplied from the inlet 2 and rising. ing. As shown in an enlarged view in FIG. 2, the fins 10 are arranged such that some of the fins that are mutually adjacent to each other are positioned in front and back relative to the upward flow direction of the fluid. That is, when the fins 10 of the heat transfer tube 7a are projected onto a plane perpendicular to the upward flow of the high-temperature fluid A, the fins adjacent to each other are arranged to overlap each other. In addition, the fins in contact with the heat exchanger tubes are arranged perpendicularly to the heat exchanger tubes, and the burring processing part 10a'' that fixes (joins) the fins 10 and the heat exchanger tubes 7a can be easily manufactured, and this burring processing increases the strength of the fins themselves. increases.

Now, the high temperature fluid A that has flowed into the casing 1 from the inlet 2 is uniformly distributed within the casing 1 by the distribution plate 4.
It passes through the particle layer 5 and the empty tower section 6 and is discharged from the outlet 3 to the outside of the apparatus. On the other hand, the heated fluid B enters the finned heat exchanger tube 7a in the empty tower section 6 from the heat exchanger tube population 8, is heated while passing through the heat exchanger tube 7b located in the particle layer 5, and flows out from the heat exchanger tube outlet 9. do. Therefore, the particles in the particle layer 50 are repelled by the high-temperature fluid A, but the particles C scattered from the particle layer 5 are caused by the fins 10 of the heat transfer tubes 7a being partially located in the front and rear positions with respect to the flow direction of the high-temperature fluid. Since they overlap, they collide with the fins, fall into the particle layer where they do not lose kinetic energy, and the scattered particles C do not pass through the finned heat exchanger tube 73 section and proceed to the discharge port 3 side. .

On the other hand, the high temperature fluid A easily passes through the gaps between the fins 100 and flows out from the outlet 3.

The fins 10 are fixed (joined) by the heat exchanger tube 7a and the burring part 10a, and the fins of the burring part are perpendicular to the heat exchanger tube, so the heat exchanger tube 7a and the fins 10 can be easily assembled and fixed. It turned out fine and fin 1
The strength of 0 itself also increases.

Since the fins 10 are well fixed to the heat transfer tubes 7a (because the fins change from a flat plate to an uneven shape and the moment of inertia of the area increases), heat transfer from the high temperature fluid A through the fins 10 is also good. The heat exchange efficiency increases, the temperature of the high temperature fluid A decreases, the volume decreases, and the flow velocity decreases, making it easy to change the direction of the fluid without causing much passage resistance.

In the above embodiment, both ends of the fin 10 are inclined in the same direction, but as shown in FIG. 3, the upper and lower ends may be inclined in opposite directions. Also in this case, when each fin is projected onto a plane perpendicular to the upward flow of the high-temperature fluid, adjacent fins overlap each other, so that the same effect as in the first embodiment can be achieved.

〔Effect of the invention〕

As explained above, in the present invention, the heat exchanger tube disposed in the cavity formed at the upper part of the fluidized bed of particles has fins that are inclined with respect to the upward flow direction of the high-temperature fluid and that are adjacent to each other. Since the fins are provided so that a part of the fins are located in front and back relative to the upward flow direction of the fluid, the fins prevent particles from scattering above the heat exchanger tubes in the cavity, and therefore the air The height of the tower can be reduced to 1/2 to 1/4 compared to conventional ones, and the height of the entire device can be reduced.

Moreover, unlike the case where a wire mesh is used to prevent particles from scattering, the fluid flow path is not blocked. The fins at the burring part where the fins and heat transfer tubes join are perpendicular to the heat transfer tubes, making the burring process easy, easy to assemble, and a sufficient bond, which improves the heat transfer characteristics of the fins. It also increases the strength of the fin itself.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional side view of a fluidized bed heat exchanger according to an embodiment of the present invention, FIG. 2 is an enlarged view showing the relationship between finned heat exchanger tubes and scattered particles, and FIG. 3 is another embodiment of the present invention. FIG. 3 is an enlarged view of a finned heat exchanger tube according to an example. 1...Casing, 2...Inlet, 3...
Discharge port, 5...Particle layer, 6... Sky tower section, 7
Heat exchanger tube, 10...fin. (731,7) Agent Patent Attorney Noriyuki Chika
(1 other person) Figure 1 β

Claims (2)

[Claims] (1) In a fluidized bed heat exchanger that has heat transfer tubes in the fluidized bed and in the empty column, the heat transfer tubes installed in the empty column are provided with fins, and the fins in contact with the heat transfer tubes are perpendicular to the heat transfer tubes. 1. A fluidized bed heat exchanger characterized in that the fins are arranged such that the ends of the fins are inclined in the same direction and adjacent fins are located in front-back relationship with respect to the upward flow direction of the high-temperature fluid. (2) The ends of the fins are inclined in opposite directions j7
A fluidized bed heat exchanger according to claim 1, characterized in that: