JPH05231784A - Fluidized bed heat exchanger - Google Patents

Abstract

PURPOSE:To provide a fluidized bed heat exchanger capable of realizing reliability of heat exchanger having a superior heat transfer performance and a reduction of operation cost by a method wherein adhesion or accumulation of material containing fluid to a wall of the heat transfer pipe even in the heat exchanger having heat exchanging fluid containing gas having dusts or soots and the like as well as shell side fluid and fluid within the heat transfer pipe or liquid containing waste oil, scale composition and aqueous living things or the like as heat exchanging fluid. CONSTITUTION:Shell side fluid (a) is supplied from an inlet port 6 to a shell side fluid flowing part 12, passes through a dispersion plate 4, enters a fluidized bed 13 to cause flowing particles 10 within the shell to be severely flowed therein, thereafter the fluid passes through the outlet buffer 14 and the fluid is discharged out of the shell at the shell fluid outlet port 7. Fluid (b) within the heat transfer pipe enters from an in-pipe fluid inlet port 8 into a heat transfer pipe inside fluid flowing-in part 15, passes through the dispersion plate 5, is supplied into a heat transfer pipe inside fluidized bed part 16 so as to cause the flowing particles 11 to be severely flowed, the fluid passes through an outlet buffer 17 and then is discharged out of the heat exchanger.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluidized bed heat exchanger for forming a fluidized bed on the shell side and the inside of a heat transfer tube and performing heat exchange operation.

[0002]

2. Description of the Related Art In a heat exchanger, when a gas containing dust, soot, etc. or a liquid containing waste oil, scale components, aquatic organisms, etc. is used for both the shell side fluid and the heat transfer tube inner fluid, dust and soot contained in the gas are used. Alternatively, waste oil, scale components, aquatic organisms, etc. contained in the liquid adhere to the heat transfer tube wall,
Accumulation will cause serious problems in the performance of the heat exchanger, such as corrosion of the heat transfer tubes and deterioration of heat transfer performance.

Therefore, as a method for cleaning the heat transfer tube, scraping with a brush, impact with a hammer, cleaning with a sponge ball, etc. have been devised.
It is necessary to periodically stop the operation of the heat exchanger, which has a drawback that maintenance and management costs and operation costs increase due to frequent operations.

[0004]

As described above, in the heat exchanger, when a gas containing dust, soot, etc. or a liquid containing waste oil, scale components, aquatic organisms, etc. is used as the heat exchange fluid, it is included in the gas. Dust, soot or waste oil contained in the liquid, scale components, aquatic organisms, etc. easily adheres to and accumulates on the heat transfer tube wall, causing corrosion and deterioration of heat transfer performance. Deposits must be regularly removed from the heat transfer tubes. Further, since the cleaning operation in the conventional heat exchanger has to be performed after the operation of the heat exchanger is stopped, the maintenance cost of the heat exchanger and the actual operating time are reduced, resulting in a sharp increase in the operating cost. Had a problem.

From the above, even if the heat exchanger is operated for a long time (heat exchange operation), it is possible to prevent the fluid inclusions from adhering to and depositing on the wall of the heat transfer tube. There is a strong demand for good heat exchangers.

The present invention has been made in order to solve such a problem, and uses a gas containing dust, soot or the like or a liquid containing waste oil, scale components, aquatic organisms and the like as the fluid on the shell side and the heat transfer tube. Also in the heat exchanger, it is possible to provide a fluidized bed heat exchanger that enables continuous operation with high reliability by surely preventing the fluid inclusions from adhering to and depositing on the heat transfer tubes. An object of the present invention is to provide a fluidized bed heat exchanger having excellent heat exchange efficiency by allowing counterflow of the side fluid and the fluid inside the heat transfer tube.

[0007]

A fluidized bed heat exchanger according to the present invention has a shell and a plurality of heat transfer tubes vertically arranged in the shell, and the fluid is made to flow by the fluid flowing on the shell side. The fluidized bed is formed by holding the particles, and the fluidized bed is formed on the inner side of the heat transfer tube by holding the fluidized particles that are made to flow by the fluid flowing inside the tube.

Further, in the fluidized bed heat exchanger having the above-mentioned structure, the shell side is divided into a plurality of stages, and the fluidized bed is formed at each stage, whereby the shell side fluid and the fluid in the heat transfer tube are opposed to each other. It is characterized by enabling a heat exchanger.

[0009]

In the fluidized bed heat exchanger of the present invention, when the shell-side fluid and the fluid inside the heat transfer tube are both gas containing dust, soot, etc. or liquid containing waste oil, scale components, aquatic organisms, etc. By forming a fluidized bed both inside and outside the heat pipe, dust, medium or waste oil, scale components, aquatic organisms, etc., adhere to the inner and outer walls of the heat transfer pipe, deposits, frictional force, impact force and fluid transfer force of fluidized particles. The heat exchanger tube can be removed by corrosion, and not only can the heat transfer tube be prevented from being corroded and the heat transfer performance from being deteriorated, but also a heat exchanger with excellent heat transfer performance can be realized, and the cleaning operation of the heat transfer tube becomes unnecessary. It is possible to improve the reliability of the heat exchanger and reduce the operating cost.

Further, the shell side of the fluidized bed heat exchanger is divided into a plurality of stages, and a fluidized bed is formed at each stage, whereby the counter flow heat exchange between the shell side fluid and the fluid in the heat transfer tube is performed. This makes it possible to realize a heat exchanger with excellent heat exchange efficiency.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing a fluidized bed heat exchanger according to an embodiment of the present invention.

This fluidized bed heat exchanger comprises a shell 1, a plurality of heat transfer tubes 2 arranged vertically in the shell 1, a tube plate 3,
A shell-side dispersion plate 4 and a heat-transfer-tube inner-dispersion plate 5, in which a gas containing dust, phosphorus, etc. or a liquid containing waste oil, scale components, aquatic organisms, etc., has different temperatures, respectively, shell-side fluid a and heat-transfer tube inner fluid b. As heat transfer tube 2 and tube plate 3
The shell side fluid a inlet 6 is provided at the lower part of the side surface of the shell, the outlet 7 is provided at the upper part, and the heat transfer tube is provided at the lower part and the upper part of the heat exchanger, respectively. Inside entrance 8 and exit 9 are installed. Further, the shell side fluidized particles 10 are provided on the shell side,
The fluid particles 11 inside the heat transfer tube are held in the heat transfer tube. Therefore, the shell side fluid inflow portion 1 is provided on the shell side.
2, a shell-side fluidized bed portion 13, a shell-side outlet buffer portion 14, and also inside the heat transfer tube, a heat transfer tube inner fluid inflow portion 15, a heat transfer tube inner fluidized bed portion 16, and a heat transfer tube inner outlet buffer portion 17 .

The shell-side fluid a is supplied from the inlet 6 to the shell-side fluid inflow portion 12, passes through the dispersion plate 4, and then enters the fluidized bed portion 13 to vigorously flow the fluidized particles 10 retained in the shell. To form a fluidized bed. Thereafter, the fluid a is discharged from the shell side fluid outlet 7 to the outside of the shell through the outlet buffer portion 14. The fluid b inside the heat transfer tube is
From the in-tube fluid inlet 8 enters the heat transfer tube inner fluid inflow portion 15, passes through the dispersion plate 5, is supplied into the heat transfer tube inner fluidized bed portion 16, and the fluidized particles 11 retained therein are vigorously fluidized to form a fluidized bed. After being formed, it is discharged from the outlet 9 to the outside of the heat exchanger through the outlet buffer portion 17.

At this time, since the fluid particles 10 and 11 are violently flowing near the outer wall surface and the inner wall surface of the heat transfer tube 2, dust, phosphorus or waste oil contained in the fluids a and b, scale components, and aquatic substances are contained. The adherence and accumulation of organisms and the like on the heat transfer tube wall is prevented by the frictional force, the impact force and the fluid carrying force of the fluidized particles. Further, the violent flow of the fluid particles 10 and 11 has an effect of thinning the boundary layer near the heat transfer tube,
Improves heat transfer performance.

FIG. 2 shows an embodiment for realizing counterflow heat exchange between the shell side fluid a and the heat transfer tube inside fluid b in the fluidized bed heat exchanger according to the present invention. In this fluidized bed heat exchanger, the shell side flow passage is divided into a plurality of stages by a partition plate 18, and each stage has a shell side fluid inflow section 12, a fluidized bed section 13, and an outlet buffer section 14, The stages are connected by a pipe 19. The shell-side fluid a enters the shell-side fluid inflow portion 12 from the inlet 6 provided at the lower part of the joke portion near the shell side, passes through the dispersion plate 4, and then passes through the fluidized bed portion 13 and the outlet buffer portion 14 to the pipe 19. Are sequentially sent to the lower stage. Then, it is discharged to the outside of the shell from the shell side fluid outlet 7 installed in the upper part of the lowermost stage. In addition, the heat transfer tube inner side fluid b enters the heat transfer tube inner side fluid inflow portion 15 from the in-tube fluid inlet 8 and passes through the dispersion plate 5,
It is discharged from the outlet 9 to the outside of the heat exchanger through the fluidized bed portion 16 inside the heat transfer tube and the outlet buffer portion 17.

Here, the temperature changes of the shell side fluid a and the heat transfer tube inner side fluid b from the inlet to the outlet in the heat exchanger of FIG. 2 are shown in FIG. 3 as the shell side fluid a at a high temperature and the heat transfer tube inside fluid b as a low temperature. The case where the fluid on the side is used is shown. In the figure, the horizontal axis is the distance Z [m] from the lower part of the heat exchanger, the vertical axis is the fluid temperature T [° C], the polygonal line A is the shell side fluid a, and the straight line B is the heat transfer tube inner fluid b. It shows the temperature change. Focusing on the broken line A, the shell-side fluid a and the heat transfer tube inner-side fluid b are parallel flows that flow in the same direction (upward flow) in each stage on the shell side. Seen from above, the fluid a and the fluid b are quasi-opposing flows that flow in opposite directions. Therefore, the temperature difference between the fluid a and the fluid b can be effectively exchanged, and a fluidized bed heat exchanger having a high heat exchange rate is realized.

[0017]

As described above, according to the present invention, even when a gas containing dust, soot or the like or a liquid containing waste oil, scale components, aquatic organisms and the like is used for both the shell side fluid and the heat transfer tube inner side fluid, the shell is used. By forming a fluidized bed on both sides of the heat transfer tube and inside the heat transfer tube, it is possible to prevent dust, soot or waste oil, scale components, aquatic organisms, etc. from adhering and accumulating on the inner and outer walls of the heat transfer tube, resulting in corrosion of the heat transfer tube.
It is possible to realize a heat exchanger with excellent heat transfer performance without deterioration of heat transfer performance, eliminate the need for cleaning the heat transfer tubes, and improve the reliability of the heat exchanger and reduce operating costs.

Further, the shell side of the fluidized bed heat exchanger is divided into a plurality of stages so that the shell side fluid and the fluid inside the heat transfer tube can exchange heat in opposite directions, and heat exchange with excellent heat exchange efficiency can be achieved. Can be realized.

[Brief description of drawings]

FIG. 1 is a sectional view showing a fluidized bed heat exchanger according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a fluidized bed heat exchanger according to another embodiment of the present invention.

FIG. 3 is a view showing temperature changes of a shell side fluid and a heat transfer tube inside fluid.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Shell 2 ... Heat transfer tube 3 ... Tube plate 4 ... Shell side dispersion plate 5 ... Heat transfer tube inner side dispersion plate 10 ... Shell side fluidized particles 11 ... Heat transfer tube inside fluidized particles 12 ... Shell side fluid input part 13 ... Shell side fluidized bed Part 14 ... Shell side outlet buffer part 15 ... Heat transfer tube inner side fluid input part 16 ... Heat transfer tube inside fluidized bed part 17 ... Heat transfer tube inside exit buffer part 18 ... Partition plate.

Claims (2)

[Claims] 1. A shell and a plurality of heat transfer tubes vertically arranged in the shell, wherein a fluidized bed is formed by holding fluid particles that are made to flow by the fluid flowing on the shell side, and A fluidized bed heat exchanger characterized in that it also holds fluidized particles that are made to flow by a fluid flowing inside the heat transfer tube to form a fluidized bed. 2. The shell side is divided into a plurality of stages,
The fluidized bed heat exchanger according to claim 1, wherein a fluidized bed is formed in each stage.