JP7660464B2 - Heat exchanger - Google Patents

Description

A heat exchanger is a device that transfers heat (exchanges heat) from a warm fluid to a cold fluid, and the fluid used can be liquid or gas. If the fluid contains solid foreign matter, the solid matter may remain and accumulate within the flow path. The accumulation of this solid matter has a detrimental effect on the heat exchanger, causing blockage of the flow path and reduced heat exchange efficiency.

Methods known to remove accumulated solid foreign matter include circulating a chemical solution such as an acid or alkali inside the heat exchanger, or filling the inside of the heat exchanger with the chemical solution and then inserting a nozzle into the flow path to inject high-pressure air and clean and remove the foreign matter by the bubbling action. However, these methods have drawbacks, such as requiring the operation to be temporarily stopped and the bubbling action only having a localized effect.

To address this shortcoming, Patent Document 1 discloses technology relating to a heat exchanger structure in which air outlet holes are drilled into a tubular baffle plate retaining rod fixedly installed inside the can shell, and an air inlet pipe is arranged outside the can shell to connect to the baffle plate retaining rod. With this technology, the entire inside of the can shell is effectively bubbling cleaned, and adhesion of solid foreign matter to the tube walls is sufficiently prevented or can be completely cleaned and removed, ensuring normal and safe operation.

Japanese Utility Model Publication No. 57-41593 Japanese Patent Application Publication No. 9-61072

However, the technology in Patent Document 1 involves bubbling cleaning by ejecting high-pressure gas into a liquid, and is designed to be used when the fluid flowing through the heat exchanger is a liquid. It is unclear whether bubbling cleaning will occur when the fluid is a gas. Therefore, the problem that the present invention aims to solve is to provide a heat exchanger that can efficiently clean the flow path through which the gas flows.

The aspects of the invention for solving the above problems are as follows.
(First aspect)
A heat exchanger that performs heat exchange between a first gas flowing outside a plurality of heat transfer tubes arranged in parallel and extending in a vertical direction and a second gas flowing inside the heat transfer tubes,
the first gas is a gas containing solid foreign matter,
A baffle plate for changing the flow direction of the first gas;
An air pipe through which compressed air flows, which is arranged in parallel with the heat transfer pipe;
The air pipe is provided with a blowing section from which compressed air is blown out,
The compressed air blows against the baffle plate.
A multi-tube heat exchanger characterized by:

When a heat exchanger that uses gas as the flowing fluid is used continuously, the gas supplied contains solid foreign matter such as dirt, dust, and other particles, which then flow into the flow path. The flow path is composed of, for example, heat transfer tubes, the inner walls of the tube body, and baffle plates, and as the gas flows, the solid foreign matter adheres to the heat transfer tubes, the inner walls of the tube body, and the baffle plates, and gradually accumulates. For this reason, in the past, the use of heat exchangers was restricted by providing a cleaning means as described in Patent Document 1, or by handling the gas containing solid foreign matter so as not to flow into the shell-side flow path in the first place.

In this embodiment, the blown compressed air is blown onto the baffle plate, so that solid foreign matter accumulated on the baffle plate is blown off and removed by the blowing of compressed air. In addition, when compressed air is blown into the flow path, the internal pressure of the flow path is instantaneously increased, and the impact of the pressurization extends to the components of the flow path, such as the heat transfer tube, the inner wall of the copper tube, and the baffle plate. As a result, solid foreign matter that has adhered to and accumulated on these components is blown up or moved by the impact. The impacted solid foreign matter then flows together with the gas flowing through the flow path and is discharged from the heat exchanger. Patent Document 2 is a heat exchanger that has a porous heat transfer material, and the mechanism for blowing compressed air is different from this embodiment.

The present invention provides a heat exchanger that can efficiently clean the flow path through which gas flows.

FIG. 1 illustrates an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line AA of FIG. FIG. 2 is a cross-sectional view taken along the line BB in FIG. FIG. 2 is a cross-sectional view taken along line AA of FIG. FIG. 4 is a diagram showing an example of the arrangement of heat transfer tubes.

First Embodiment
Next, an embodiment of the present invention will be described. Note that the embodiment is an example of the present invention. The scope of the present invention is not limited to the scope of the embodiment.

The multi-tube heat exchanger 1 of this embodiment is a heat exchanger 1 that performs heat exchange between a first gas flowing outside the heat transfer tubes 12 and a second gas flowing inside the heat transfer tubes 12 through a plurality of heat transfer tubes 12 arranged in parallel extending in the vertical direction, the first gas being a gas containing solid foreign matter, and is characterized in that it is equipped with baffle plates 13 (13a, 13b, 13c, 13d, ...) that change the flow direction of the first gas, air tubes 11 through which compressed air flows that are arranged in parallel to the heat transfer tubes 12, and a blowing section 11a from which compressed air is blown into the air tube 11, and the blown compressed air blows against the baffle plate 13. Hereinafter, one embodiment of the present invention will be described with reference to FIG. 1.

(Flow path)
The multi-tubular heat exchanger 1 of this embodiment has two types of flow paths, a tube-side flow path and a shell-side flow path, which do not intersect with each other. The second gas 32 flows inside the heat transfer tube 12, i.e., in the tube-side flow path, flows in from the second inlet 51 provided in the upper part of the tube body 2, passes inside the heat transfer tube 12, and flows out as the second gas 33 after heat exchange from the second outlet 6a provided in the lower part of the tube body 2. The first gas 30 flows outside the heat transfer tube 12 in the tube body 2, i.e., in the shell-side flow path, flows in from the first inlet 3 provided below the second inlet 51 in the tube body 2, passes outside the heat transfer tube 12, and flows out as the first gas 31 after heat exchange from the first outlet 4 provided above the second outlet 6a in the tube body 2. The second inlet section 51 and the first inlet section 3 are separated by a partition wall 5a, so that the second gas 32 flowing in from the second inlet section 51 does not mix with the first gas flowing in from the first inlet section 3. The second outlet section 6a and the first outlet section 4 are separated by a partition wall 5b, so that the second gas passing through the inside of the heat transfer tube 12 does not mix with the first gas passing through the outside of the heat transfer tube 12. The heat exchanger 1 of this embodiment can be installed so that the axial direction of the tube body 2 is aligned along the vertical direction, and of the vertical direction, the upward direction represents the direction of symbol U in Fig. 1 and the downward direction represents the direction of symbol D in Fig. 1.

(upper chamber, middle chamber, lower chamber)
The tube body 2 is divided into an upper chamber 52, a middle chamber 53, and a lower chamber 54 from the top. The upper chamber 52 and the middle chamber 53 are separated by a partition wall 5a, and no fluid flows between the two chambers. The middle chamber 53 and the lower chamber 54 are separated by a partition wall 5b, and no fluid flows between the two chambers. The base end of the heat transfer tube 12 is located in the upper chamber 52, and the tip end is located in the lower chamber 54. The second gas that flows into the upper chamber 52 from the second inflow portion 51 flows into the inside of the heat transfer tube 12 from the base end of the heat transfer tube 12, is released from the tip of the heat transfer tube 12 into the lower chamber 54, and flows out of the heat exchanger 1 from the second outflow portion 6a. The lower chamber 54 is preferably formed into a hopper shape 6 so that the second gas can easily flow out.

The middle chamber 53 is provided with a baffle plate 13 so as to block the flow direction of the first gas. If the baffle plate 13 were not present, the first gas would flow into the middle chamber 53 from the first inlet 3 located at the upper side of the middle chamber 53 and flow toward the first outlet 4 located at the lower side of the middle chamber 53. However, due to the presence of the baffle plate 13 in this embodiment, the flow direction is changed and the first gas proceeds to the first outlet 4 while meandering.

The baffle plate 13 has a planar shape extending horizontally with respect to the tube body 2 extending vertically, and has an opening with the diameter of the heat transfer tube 12 and an opening with the diameter of the air tube 11, through which the heat transfer tube 12 and the air tube 11 are inserted. The baffle plate 13 also has a notch 14, and the first gas passes through the notch 14 to approach the first outflow section 4.

At least one baffle plate 13 can be provided in the middle chamber 53. For convenience, the baffle plates are distinguished from the top as baffle plate 13a, baffle plate 13b, baffle plate 13c, ... (a total of five baffle plates 13 are shown in FIG. 1, from baffle plate 13a to baffle plate 13e). In addition, the notch of baffle plate 13a is given the symbol 14a, and from the top as baffle plate 13a's notch, baffle plate 13b's notch, baffle plate 13c's notch, ...

A preferred embodiment has multiple baffle plates 13 spaced apart in the vertical direction. If there are multiple baffle plates 13, the first gas will meander and will not flow linearly toward the first outlet 4. In addition, a preferred embodiment has the notches 14 of adjacent baffle plates 13 positioned differently in the circumferential direction of the heat exchanger 1. In this embodiment, when the middle chamber 53 is viewed in the vertical direction, the adjacent notches 14 do not overlap exactly, and the first gas will meander significantly through the middle chamber 53 and will remain in the middle chamber 53 for a relatively long time, thereby improving the efficiency of heat exchange. The circumferential direction of the heat exchanger 1 refers to the direction in which the heat transfer tubes 12 of the heat exchanger 1 draw an arc around the axis when the axis is assumed to be along the vertical direction.

In addition, in a configuration in which the positions of the notches 14 in adjacent baffle plates 13 are mutually different in the circumferential direction of the heat exchanger 1, for example, it is preferable that the notches 14a and 14b differ by an angle of 150° to 180° in the circumferential direction of the heat exchanger 1, because the first gas will progress in a large meandering manner. The shape of the notches 14 can be, for example, a line segment with any two points on the circumference of the baffle plate 13 as end points, but the line segment may be straight or curved, and if the heat transfer tube 12 or air tube 11 is located on the line segment, it is preferable to cut out the notch so that it does not come into contact with (does not hit) the heat transfer tube 12 or air tube 11.

The flow direction of the first gas may be from the first inlet 3 to the first outlet 4, or conversely, from the first outlet 4 to the first inlet 3. The flow direction of the second gas may be from the second inlet 51 to the second outlet 6a, or conversely, from the second outlet 6a to the second inlet 51.

(Partition wall)
The partitions 5a, 5b have a planar shape extending horizontally with respect to the tube shell 2 extending vertically, and an opening with a diameter of the heat transfer tube 12 and an opening with a diameter of the air tube 11 are formed, and the heat transfer tube 12 and the air tube 11 can be inserted into these openings. The heat transfer tube 12 and the air tube 11 can be arranged such that their leading ends are fixed by the partition 5a and their lower ends are fixed by the partition 5b. At least one heat transfer tube 12 and one air tube 11 can be provided.

(Heat transfer tube)
The heat transfer tubes 12 are arranged in parallel and extend in the vertical direction.

(Air tube)
The air pipe 11 is arranged in parallel with the heat transfer pipe 12, and compressed air flows through it. The base end 11b of the air pipe 11 is connected to the air pipe 20, and the air pipe 20 is supplied with compressed air from the air header 9. When a plurality of air pipes 11 are provided, the air pipes 20 are also formed of a group of air pipes 20 consisting of the number of air pipes 11, and the base end 11b side of each air pipe 11 is connected to each air pipe. The air header 9 may be, for example, a form in which compressed air generated by a blower or compressor is sent to the air pipe 11, or a form in which pulse air is used for backwashing a bag filter provided in an incineration facility having a heat exchanger. The air pipe 20 may be provided with a valve 7 (for example, a pulse jet valve, etc.) for adjusting the amount of compressed air sent and an opening adjustment means 8 for adjusting the opening of the valve 7. The tip of the air pipe 11 has a bottom and is preferably located at the bottom of the middle chamber 53. It is preferable to provide at least one air pipe 11. For example, if one to six air pipes are provided, compressed air can be blown evenly onto the baffle plate 13, and accumulated solid foreign matter can be effectively suspended.

The compressed air blowout can be controlled so that the compressed air is blown out intermittently for 100 to 2000 milliseconds. Examples of intermittent blowout of compressed air include a method of controlling the blowout interval with a timer, or a method of controlling based on a temperature difference.

As for the timer control method, it is preferable to blow compressed air onto the heat exchanger 1 that is continuously operating, for example, once every 30 minutes to 48 hours, and more preferably once every 8 to 24 hours. If the interval is shorter than 8 hours, the amount of solid foreign matter accumulated on the plate is small and the effect is poor. If the interval is shorter than 48 hours, the accumulated solid foreign matter is not sufficiently removed and the cleaning effect is poor. However, this interval can be made longer or shorter depending on the concentration of solid foreign matter contained in the gas, and is not generally determined.

Regarding the method of controlling based on the temperature difference, first, if the temperature difference between the inflow temperature and outflow temperature of the first gas in the heat exchanger 1 in a state where no solid foreign matter is accumulated on the baffle plate 13 (this temperature difference is also called the "optimum value during normal operation") is ΔT ₀ , the temperature difference ΔT will decrease as the operation continues. Therefore, it is preferable to configure the compressed air to be blown out when the temperature difference ΔT becomes equal to or less than a predetermined value. Although the temperature difference ΔT cannot be determined in general, as an example of operation using the embodiment product, the compressed air can be blown out when the temperature difference ΔT becomes equal to or less than 90% of ΔT _0. The inflow temperature of the first gas in the heat exchanger 1 refers to the temperature of the first gas flowing through the first inflow section 3, and can be measured, for example, by a temperature sensor installed in the first inflow section 3. The outflow temperature of the first gas in the heat exchanger 1 refers to the temperature of the first gas flowing through the first outflow section 4, and can be measured, for example, by a temperature sensor installed in the first outflow section 4. For example, if the appropriate value ΔT ₀ during normal operation is 200° C., compressed air can be blown out when ΔT falls to 180° C. or less. When solid foreign matter accumulates in the flow path, the flow path narrows, and the first gas that has flowed in flows out from the first outflow section 4 faster than initially. This reduces the heat exchange efficiency, and the difference in temperature of the first gas at the first inflow section 3 and the first outflow section 4 becomes smaller. Therefore, the amount of solid foreign matter accumulated in the flow path can be estimated from the temperature difference ΔT, and the timing of blowing out the compressed air can be controlled using the temperature difference ΔT. Immediately after the compressed air is blown out, the solid foreign matter is removed and the temperature difference becomes large.

It is also effective to combine a timer control method with a temperature difference control method. When using such a combined method, effective cleaning can be expected if the compressed air is controlled to be blown out when (1) 30 to 1,500 minutes have elapsed since the heat exchanger 1 was operated or the compressed air was last blown out, or (2) the difference ΔT between the inlet temperature and the outlet temperature of the first gas becomes 90% or less, whichever occurs first.

When compressed air is blown onto the baffle plate 13, the solid foreign matter will fly up even if it is not blown directly onto the solid foreign matter. This is due to the following action. When compressed air is blown into the shell side flow passage, the gas in the shell side flow passage is instantly pressurized, and the impact also reaches the solid foreign matter. The solid foreign matter that has accumulated on the baffle plate 13 gains momentum due to the impact, and as a result, it flies up or slides.

The air pipe 11 is provided with a blowing section 11a through which compressed air is blown into the shell-side flow path. If each air pipe 11 is provided with multiple blowing sections 11a spaced apart in the vertical direction, compressed air is blown out vertically within the middle chamber 53, and solid foreign matter accumulated in various places is blown up by the wind pressure, which is preferable.

It is also preferable that at least one blowing section 11a is located near and above each baffle plate 13 so that the compressed air directly hits the baffle plate 13. Here, "near the baffle plate 13" refers to a distance between the baffle plate 13 and the blowing section 11a closest to the baffle plate 13 (for example, the distance of a perpendicular line from the blowing section 11a closest to the baffle plate 13 to the baffle plate 13) being 50 mm or less, more preferably 10 mm or less, although this cannot be generalized as it depends on the flow speed of the blown compressed air.

The shape of the blowing section 11a in the air pipe 11 is shown in Figure 3. In Figure 3, multiple blowing sections 11a are provided at intervals around the circumference of the air pipe 11, and one is also provided at the bottom of the air pipe 11. In Figure 3, six blowing sections 11a are provided around the circumference of the air pipe 11, but the number is not limited and 6 to 12 can be provided. The blowing section 11a provided at the bottom of the air pipe 11 is provided to blow away solid foreign matter accumulated on the partition wall 5b.

When the blowing section 11a is located near and above the baffle plate 13, it is preferable that the blowing section 11a blows compressed air downward. Most of the solid foreign matter accumulates on the upper surface of the baffle plate 13, so it is easy for it to fly up when blown from above.

The blowing section 11a is not particularly limited as long as it blows out compressed air, but for example, it can be a nozzle with a diameter of 1 to 10 mm. It is preferable that the compressed air be blown out from the nozzle at a flow rate of 20 to 100 Nm/sec. If the flow rate of the compressed air is too low, it will not be able to blow away solid foreign matter with sufficient force, and if the flow rate is too high, it may produce a loud noise.

An example of a specific form of the air pipe 11 is as follows: 37 blowing sections 11a are provided, the nozzle diameter of the blowing sections 11a is 5 mm, the air volume per air pipe is 0.65 ^Nm3 /sec, the compressed air blowing time per time is 200 milliseconds, the compressed air blowing volume per air pipe is 0.13 Nm3/time, the blowing interval is 30 minutes, the required amount of compressed air is 5 NL/min, and the volume of the air header 9 is 0.15 ^m3 .

Figure 2 is a cross section taken along the line A-A in Figure 1. A large number of heat transfer tubes 12 and air tubes 11 are arranged in the tube body 2. The air tubes 11 are arranged at intervals in the circumferential direction of the tube body 2. Also shown is baffle plate 13b (hatched area consisting of multiple straight lines drawn from the upper left to the lower right of the page) and adjacent baffle plate 13c below it. Since baffle plate 13c is below baffle plate 13b, in reality, the part of baffle plate 13c that faces notch 14b of baffle plate 13b (excluding the hatched part) is visible. Notch 14c of baffle plate 13c is not actually visible, so it is shown by a broken line. Figure 2 shows a configuration in which the positions of the notches in adjacent baffle plates 13b and 13c are 180° different (shifted) from each other in the circumferential direction of the heat exchanger. In FIG. 2, a perpendicular line (dotted line) is hung from the axis of the tube body 2 to the notch portion 14b, and a perpendicular line (dotted line) is hung from the axis of the tube body 2 to the notch portion 14c, and the angle between the two perpendicular lines is 180°. Although not shown, the positions of the notches in the baffle plates 13a and 13b, the positions of the notches in the baffle plates 13c and 13d, and the positions of the notches in the baffle plates 13d and 13e may be different from each other by 180° in the circumferential direction of the heat exchanger. In addition, the positions of the notches in adjacent baffle plates may be different (shifted) from each other by 150° to 180° in the circumferential direction of the heat exchanger. FIG. 4 shows a form in which the positions of the notches in adjacent baffle plates are different (shifted) from each other by 150° in the circumferential direction of the heat exchanger. In FIG. 4, a perpendicular line (dotted dashed line) is hung from the axis of the tube body 2 to the cutout portion 14b, and a perpendicular line (dotted dashed line) is hung from the axis of the tube body 2 to the cutout portion 14c, and the angle between the two perpendicular lines is 150°.

The arrangement of the heat transfer tubes 12 is not particularly limited as long as the heat exchange efficiency is good. For example, as shown in FIG. 5, examples include (a) a square serial arrangement, (b) a square staggered arrangement, (c) a triangular staggered arrangement, and (d) a triangular serial arrangement.

If the positions of the notches in the adjacent baffle plates are different from each other in the circumferential direction of the heat exchanger, the first gas meanders through the different notches in the circumferential direction of the heat exchanger. Specifically, the flow direction of the first gas that flows into the shell-side flow passage is changed by the baffle plate 13a, flows along the surface of the baffle plate 13a, and passes through the notch portion 14a of the baffle plate 13a toward the adjacent baffle plate 13b. After that, the first gas flows along the surface of the baffle plate 13b, passes through the notch portion 14b of the baffle plate 13b toward the adjacent baffle plate 13c. Furthermore, the first gas flows along the surface of the baffle plate 13c, passes through the notch portion 14c of the baffle plate 13c toward the adjacent baffle plate 13d. If there are further adjacent baffle plates 13, the first gas flows in the above manner and finally reaches the first outlet portion 4. At this time, some of the solid foreign matter already attached to the baffle plate 13 will begin to flow due to the wind pressure of the flowing first gas, while others will remain attached.

In addition, when the first gas flows into the tube body 2 from the first inlet 3 and flows out from the first outlet 4, solid foreign matter accumulated on the baffle plate 13a is blown away by the blowing of compressed air and falls from the notch 14a onto the baffle plate 13b provided below. The fallen solid foreign matter is blown away by further blowing of compressed air and falls from the notch 14b onto the baffle plate 13c provided below. This blowing away by compressed air is repeated, and the solid foreign matter falls successively onto the baffle plate 13 in the lower stage, and finally flows out from the first outlet 4 together with the first gas.

(others)
The first gas flowing through the heat exchanger 1 contains solid foreign matter and is not particularly limited, and examples thereof include exhaust gas and dry exhaust gas generated in automobiles, gas turbines, incinerators, thermal power plants, and factories. The second gas may or may not contain solid foreign matter and is not particularly limited, and examples thereof include exhaust gas and dry exhaust gas generated in automobiles, gas turbines, incinerators, thermal power plants, and factories, and outside air. If the concentration of solid foreign matter contained in the first gas is 0.001 to 0.1 g/m ³ , it is preferable because even if the solid foreign matter accumulates in the flow path, it is easy to remove.

<Another aspect>
The first aspect of the present invention has been described above. In addition to this aspect, the following aspect is also desirable.
(Second Aspect)
The blowing portion is located near and above the baffle plate.
1. The shell and tube heat exchanger of a first embodiment.

The baffle plate is plate-shaped, so solid foreign matter tends to accumulate on it. In this embodiment, the blowing section is located near and above the baffle plate, so the blown compressed air tends to hit the solid foreign matter that has accumulated on the baffle plate. This has the effect of efficiently cleaning the flow path.

(Third Aspect)
The baffle plate is provided in a plurality of spaces in the vertical direction.
1. The shell and tube heat exchanger of a first embodiment.

In this embodiment, the first gas changes its flow direction due to the multiple baffle plates and does not flow in a straight line, so it remains in the flow path for a longer period of time, which increases the efficiency of heat exchange.

(Fourth aspect)
The air pipes are arranged in parallel at intervals,
Each of the air pipes is provided with a plurality of blowing portions spaced apart in the vertical direction,
The baffle plate is provided in a plurality of spaces in the vertical direction,
At least one of the blowing sections is located near and above each of the baffle plates.
1. The shell and tube heat exchanger of a first embodiment.

The blowing section is located near and above each baffle plate, which has the effect of removing solid foreign matter that has accumulated on each baffle plate with compressed air.

(Fifth aspect)
The baffle plate has a notch,
The positions of the notches in the adjacent baffle plates are different from each other in the circumferential direction of the heat exchanger.
A shell-and-tube heat exchanger according to a fourth aspect.

Because the positions of adjacent notches are different from each other, the first gas flows in a serpentine manner, improving the efficiency of heat exchange.

(Sixth Aspect)
Compressed air is blown downward from the blowing portion.
A shell-and-tube heat exchanger according to a second embodiment.

Compressed air is blown toward the baffle plate from the blowing section located above the baffle plate, effectively removing solid foreign matter that has accumulated on the baffle plate.

(Seventh aspect)
The blowing portion is provided in plurality at intervals in the circumferential direction of the air pipe.
1. The shell and tube heat exchanger of a first embodiment.

If the blowing direction is only one direction, solid foreign objects in directions other than the blowing direction are difficult to remove and may become stuck even if compressed air is blown. With this configuration, compressed air is blown in multiple directions, so air is less likely to accumulate and solid foreign objects are prevented from sticking.

(Eighth aspect)
Compressed air is blown intermittently for 100 to 2000 milliseconds.
1. The shell and tube heat exchanger of a first embodiment.

If compressed air is blown out continuously, the flow of the first gas may be interfered with, and the efficiency of heat exchange may decrease. With this configuration, the air is blown out intermittently, which has the effect of minimizing interference with the flow of the first gas and maintaining the efficiency of heat exchange.

(Ninth aspect)
The compressed air is blown out when the temperature difference ΔT between the inflow temperature and the outflow temperature of the first gas in the heat exchanger becomes 90% or less.
1. The shell and tube heat exchanger of a first embodiment.

As the accumulation of solid foreign matter in the flow path increases, this difference becomes smaller. If compressed air is blown out when this difference falls within the above range, the accumulated solid foreign matter will be removed by compressed air when it reaches a specified amount, making cleaning effective.

This invention can be used as a multi-tube heat exchanger.

1 Heat exchanger 11 Air pipe 11a Blowout section 12 Heat transfer pipes 13a, 13b, 13c, 13d, 13e Baffle plate 14a, 14b, 14c, 14d, 14e Cutout section 30 First gas (inflow gas)
31 First gas (outflow gas)
32 Second gas (inlet gas)
33 Second gas (outflow gas)

Claims (9)

A heat exchanger that performs heat exchange between a first gas flowing outside a plurality of heat transfer tubes arranged in parallel and extending in a vertical direction and a second gas flowing inside the heat transfer tubes,
the first gas is a gas containing solid foreign matter,
A baffle plate for changing the flow direction of the first gas;
An air pipe through which compressed air flows, which is arranged in parallel with the heat transfer pipe;
The air pipe is provided with a blowing section from which compressed air is blown out,
The compressed air blows against the baffle plate.
A multi-tube heat exchanger characterized by: The blowing portion is located near and above the baffle plate.
The multi-tube heat exchanger according to claim 1 . The baffle plate is provided in a plurality of spaces in the vertical direction.
The multi-tube heat exchanger according to claim 1 . The air pipes are arranged in parallel at intervals,
Each of the air pipes is provided with a plurality of blowing portions spaced apart in the vertical direction,
The baffle plate is provided in a plurality of spaces in the vertical direction,
At least one of the blowing sections is located near and above each of the baffle plates.
The multi-tube heat exchanger according to claim 1 . The baffle plate has a notch,
The positions of the notches in the adjacent baffle plates are different from each other in the circumferential direction of the heat exchanger.
The multi-tube heat exchanger according to claim 4. Compressed air is blown downward from the blowing portion.
The multi-tube heat exchanger according to claim 2. The blowing portion is provided in plurality at intervals in the circumferential direction of the air pipe.
The multi-tube heat exchanger according to claim 1 . Compressed air is blown intermittently for 100 to 2000 milliseconds.
The multi-tube heat exchanger according to claim 1 . A temperature difference between an inlet temperature and an outlet temperature of the first gas in the heat exchanger in a state in which no solid foreign matter is accumulated on the baffle plate is defined as ΔT0 _;
The compressed air is blown out when the temperature difference ΔT between the inflow temperature and the outflow temperature of the first gas in the heat exchanger becomes 90% or less of _ΔT0 .
The multi-tube heat exchanger according to claim 1 .

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