JP2009222569A - Heating medium leakage inspection device and heating medium leakage inspection method of heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heating medium leakage inspection device and a heating medium leakage inspection method of a heat exchanger for easily and early detecting leakage of a heating medium in the heat exchanger while suppressing deterioration of a function of the heat exchanger, specifying a leakage position and improving working efficiency of inspection. <P>SOLUTION: The heating medium leakage inspection device of the heat exchanger attaches a level gauge (52) by closing an inlet closing valve (38), and inspects leakage of the heating medium of the heat exchanger (10) for heat recovery by detecting variation of a heating medium amount with the level gauge while closing the inlet closing valve and an outlet closing valve (48) after pressure of the heating medium is stabilized. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a heat medium leakage inspection apparatus and a heat medium leakage inspection method for a heat exchanger that inspects leakage of a heat medium in a heat exchanger having a heat medium path through which the heat medium flows.

In recent years, as an exhaust gas treatment facility for a fuel device such as a boiler, a desulfurization device for removing sulfur oxides contained in exhaust gas generated by combustion has been provided, and the exhaust gas temperature when flowing into the desulfurization device has been provided. On the other hand, a gas gas heater for reheating the exhaust gas after passing through the desulfurization apparatus is provided for the purpose of improving the exhaust gas diffusibility from the chimney and preventing white smoke.
The gas gas heater is connected to the heat recovery heat exchanger that recovers heat from the high-temperature exhaust gas before flowing into the desulfurization device and the reheating heat exchanger that reheats the cooled exhaust gas after passing through the desulfurization device through a connecting pipe. Thus, a heat medium such as water circulates between the heat exchangers through the communication pipe.

A heat exchanger such as the heat recovery heat exchanger and the reheating heat exchanger is formed by a heat transfer tube group in which a plurality of heat transfer tubes forming a heat medium path are arranged.
However, some heat transfer tubes have holes and the heat medium may leak.
Conventionally, when detecting the leakage of the heat medium, the leakage was detected from the fluctuation of the water level of the heat medium storage tank that supplies the heat medium to the heat transfer pipe and the connecting pipe in the heat exchanger. Since the amount is very large compared to the amount of leakage, the fluctuation of the water level due to leakage was very small, and it took a long time to detect the leaked heat transfer tube by looking at the storage tank.

Then, the technique which detects the leaked fluid in the said piping system by detecting the pressure in a piping system (inside a heat exchanger tube) is disclosed (refer patent document 1).
Japanese Patent Laid-Open No. 2-136795

However, as in the technique disclosed in Patent Document 1, in the case where leakage is detected by the pressure in the pipe, in the heat exchanger or the like of the gas gas heater where the temperature of the heat medium is not stable due to heat exchange with the exhaust gas, the combustion device Since the pressure fluctuates during operation, the leakage of the heat medium cannot be accurately detected.
Therefore, when detecting the leakage of the heat medium, it is necessary to detect the pressure after the temperature of the heat medium is stabilized, which also takes time.

In addition, even if the leakage of the heat medium is known, in order to identify the specific position of the leakage, the flow of the heat medium in some heat transfer tubes is stopped and the fluctuation of the water level in the heat medium storage tank is monitored. The work is repeated, and this also takes a long time, and there is a problem that work efficiency is poor.
The present invention has been made to solve such a problem. The object of the present invention is to easily and quickly detect the leakage of the heat medium in the heat exchanger while suppressing the deterioration of the function of the heat exchanger. Another object of the present invention is to provide a heat medium leakage inspection device and a heat medium leakage inspection method for a heat exchanger that can identify the leakage position and improve the work efficiency of the inspection.

  In order to achieve the above-described object, in the heat exchanger leakage inspection device for a heat exchanger according to claim 1, a heat exchanger for inspecting leakage of the heat carrier in a heat exchanger having a heat medium passage through which the heat medium flows is provided. In the heat medium leakage inspection device, provided in an upstream portion of the heat medium path in the heat medium path, an upstream closing means for blocking the heat medium path, and provided in a heat medium downstream part of the heat medium path, the heat medium path When the heat medium path is blocked by the downstream closing means to be blocked and the upstream closing means and the downstream closing means, a change in the amount of the heat medium between the upstream closing part and the downstream closing part in the heating medium path is detected. And a heating medium amount detecting means.

  In the heat exchanger leakage inspection device for a heat exchanger according to claim 2, in claim 1, the heat exchanger includes a plurality of the heat medium paths in parallel, and the upstream closing means includes each of the heat medium paths. Provided in the heat medium upstream portion of the row, and the downstream closing means is provided in the heat medium downstream portion of each row of the heat medium path, and the heat medium amount detecting means includes the upstream closing means and the When the heat medium path of a predetermined row is blocked by the downstream closing means, a change in the amount of the heat medium between the upstream closed portion and the downstream closed portion in the heat medium path of the predetermined row is detected. .

In the heat exchanger leakage inspection device for a heat exchanger according to claim 3, in order to narrow the region for detecting the amount of heat medium between the upstream closing portion and the downstream closing portion of the heat medium path in claim 1 or 2. An intermediate closing means for cutting off the heat medium path at a predetermined position is provided.
According to a fourth aspect of the present invention, in the heat exchanger leakage inspection apparatus for a heat exchanger according to the first or third aspect, the region of the heat medium amount detected by the heat medium amount detector is detoured in the heat medium path. It is characterized by having a bypass route.

In the heat exchanger leakage inspection device for a heat exchanger according to claim 5, in any one of claims 1 to 4, the heat exchanger is provided in an exhaust gas passage of a combustion device and performs heat exchange with the exhaust gas. It is characterized by being.
In the heat exchanger leakage inspection method for a heat exchanger according to claim 6, in the heat exchanger leakage inspection method for a heat exchanger for inspecting leakage of the heat carrier in a heat exchanger having a heat medium passage through which the heat medium flows, An upstream closing step of blocking the heating medium path at the upstream portion of the heating medium path; a downstream closing step of blocking the heating medium path at a downstream portion of the heating medium path; and the upstream closing step. And after the downstream closing step, the amount of the heating medium for detecting a change in the amount of the heating medium between the upstream closing portion closed in the upstream closing step and the downstream closing portion closed in the downstream closing step in the heating medium path And a detection step.

  According to a heat exchanger leakage inspection method for a heat exchanger according to a seventh aspect, in the sixth aspect, the heat exchanger has a plurality of the heat medium paths in parallel. In the upstream closing step, the heat medium path is predetermined. The heating medium path is blocked at the upstream portion of the heating medium in the row, and the downstream closing means blocks the heating medium path at the downstream portion of the heating medium in the predetermined row of the heating medium path, and the heat In the medium amount detection step, after the upstream closing step and the downstream closing step, an upstream closing portion closed in the upstream closing step and a downstream closing portion closed in the downstream closing step in the heating medium path of the predetermined row It is characterized by detecting fluctuations in the amount of heat medium during the period.

  In a heat exchanger leakage inspection method for a heat exchanger according to an eighth aspect, in the sixth or seventh aspect, in the upstream closing step of the heat medium path while detecting a change in the amount of the heat medium in the heat medium amount detecting step. It has an intermediate closing step of blocking the heat medium path at a predetermined position between the closed upstream closing portion and the downstream closing portion closed in the downstream closing step so as to narrow a region for detecting the amount of the heat medium. It is said.

  The heat exchanger leakage inspection method for a heat exchanger according to claim 9 further includes a detour step of detouring the region where the amount of the heat medium detected in the heat medium amount detection step is deviated in claim 6 or 8. It is a feature.

According to the heat medium leakage inspection apparatus and the heat medium inspection method of the heat exchanger according to claims 1 and 6 of the present invention using the above means, the heat medium upstream portion of the heat medium path is closed and the heat medium downstream portion is closed. Then, the leakage of the heat medium in the heat exchanger is inspected by detecting a change in the amount of the heat medium between the upstream closing part and the downstream closing part.
That is, the upstream and downstream of the heat medium path are closed, the heat medium is held in a limited area of the heat medium path, the temperature of the area is stabilized, and the change in the amount of the heat medium in the part is detected.

As described above, it is possible to detect a change in the amount of the heat medium in a limited portion in the heat medium path with an easy operation, and to determine the change at an early stage even with a small amount of leakage.
In addition, even when leakage of the heat medium is detected, the leakage position can be identified at an early stage by checking the heat medium path in the limited region.
From the above, while suppressing the deterioration of the function of the heat exchanger, it is possible to detect the leakage of the heat medium in the heat exchanger easily and early, and to specify the leakage position, thereby improving the inspection work efficiency. Can be improved.

According to the heat medium leakage inspection apparatus and the heat medium inspection method of the heat exchanger according to claim 2 and 7, the heat exchanger has a plurality of heat medium paths in parallel, and the heat medium upstream portion and the downstream portion in a predetermined row To detect the change in the amount of heat medium.
In this way, by detecting a change in the amount of the heat medium for each predetermined row, it is possible to inspect the leakage of the heat medium only by stopping a part of the heat medium circulation of the heat exchanger.

Therefore, it is not necessary to stop the operation of the entire heat exchanger, and the function can be maintained without reducing the heat transfer performance of the heat exchanger as much as possible.
Further, since only the predetermined column where leakage is detected can be inspected, the leakage position of the heat medium can be specified, so that the inspection work efficiency can be further improved.
According to the heat medium leakage inspection apparatus and the heat medium inspection method of the heat exchanger according to claim 3 and 8, the heat medium is interposed between the upstream closing portion and the downstream closing portion that detect a change in the amount of the heat medium in the heat medium path. The heat medium path is blocked at a predetermined position in order to narrow the amount detection region.

As described above, by narrowing the region for detecting the change in the amount of the heat medium, the position where the heat medium leaks can be limited.
Thereby, the leak position of the heat medium can be specified more easily, and the work efficiency of inspection can be further improved.
According to the heat medium leakage inspection device and the heat medium inspection method of the heat exchanger according to claim 4 and 9, further leakage of the heat medium is stopped by bypassing a region where the heat medium leakage is detected, and heat exchange is performed. The deterioration of the function of the vessel can be suppressed.

Further, by bypassing the leakage area, the leakage position can be repaired during operation of the heat exchanger.
According to the heat exchanger leakage inspection device for a heat exchanger according to claim 5, when the heat exchanger is provided in the exhaust gas passage of the combustion device, heat can be easily and quickly suppressed while suppressing a reduction in exhaust gas treatment performance in the combustion device. Exchanger leakage inspection can be performed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a schematic configuration diagram of an exhaust gas treatment apparatus provided with a heat medium leakage inspection device for a heat exchanger according to the present invention.
As shown in the figure, a boiler 1 as a combustion device is provided with an exhaust gas treatment device 2 for purifying exhaust gas generated by combustion.

The exhaust gas treatment device 2 includes a denitration device 4, an air preheater 6, a heat recovery heat exchanger 10 for the gas gas heater 8, an electric dust collector 12, an incentive fan 14, a wet desulfurization device 16, and a gas gas heater 8 in the order of the exhaust gas flow. The reheating heat exchanger 18, the desulfurization fan 20, and the chimney 22 are provided.
Specifically, the denitration device 4 removes nitrogen oxides in the exhaust gas, and the air preheater 6 raises the temperature of the air supplied to the boiler 1 by heat exchange with the hot exhaust gas.

The electrostatic precipitator 12 removes soot and dust in the exhaust gas, and the incentive fan 14 pressurizes the exhaust gas after passing through the electrostatic precipitator 12 and sends it to the wet desulfurization device 16.
Further, the wet desulfurization device 16 removes SOx in the exhaust gas by gas-liquid contact, and the desulfurization fan 20 pressurizes the exhaust gas that has passed through the wet desulfurization device 16 and sends it to the chimney 22.

Further, in the gas gas heater 8, the heat recovery heat exchanger 10 and the reheating heat exchanger 18 are connected by a low temperature side communication pipe 24a (heat medium path) and a high temperature side communication pipe 24b (heat medium path). . A heat medium storage tank 26 for supplying a heat medium and a circulation pump 28 for circulating the heat medium are provided in the middle of the low temperature side communication pipe 24a.
That is, the heat medium is supplied from the heat medium storage tank 26 connected to the low temperature side communication pipe 24a, and the heat recovery heat exchanger 10 from the low temperature side communication pipe 24a, the low temperature side communication pipe 24a, and the circulation pump 28. It circulates with the reheating heat exchanger 18.

In the gas gas heater 8 configured as described above, the heat recovery heat exchanger 10 recovers heat from the high temperature exhaust gas to lower the exhaust gas temperature by the circulation of the heat medium, and the reheating heat exchanger 18 recovers the heat. It has a function of heating low-temperature exhaust gas by using heat recovered by the heat exchanger 10 for use.
Hereinafter, the heat recovery heat exchanger 10 according to the first embodiment of the present invention will be described in detail.

2 to 4, FIG. 2 is a schematic front view of a heat recovery heat exchanger according to the first embodiment of the present invention, FIG. 3 is a cross-sectional view taken along line AA of FIG. Each shows a sectional view when the level gauge is attached.
As shown in FIGS. 2 to 3, the heat recovery heat exchanger 10 is provided in an exhaust gas passage 30 having a quadrangular prism shape extending in the vertical direction and in which exhaust gas flows from below to above.

The heat recovery heat exchanger 10 includes a heat transfer tube group 34 in a bundle 32.
The heat transfer tube group 34 extends in the depth direction of the exhaust gas passage 30, and is formed by arranging a plurality of heat transfer tubes 36 (heat medium paths) arranged in parallel in the width direction by folding back in a U shape at the end and meandering in the vertical direction. Yes.

Each heat transfer tube 36 has one end connected to an inlet header 38 located outside the exhaust gas passage 30 and located above the bundle 32, and the other end located outside the exhaust gas passage 30 and located below the bundle 32. Connected to the outlet header 40.
The inlet header 38 has a cylindrical shape extending in the width direction of the exhaust passage 30. The inlet header 38 is provided with an air vent valve 42 that discharges excess air in the inlet header 38 to the outside, and is connected to the low-temperature side connecting pipe 24a. Further, an inlet closing valve 44 (upstream closing means) capable of blocking the heat medium path is provided in the vicinity of the inlet header 38 of the low temperature side communication pipe 24a.

  The outlet header 40 has a cylindrical shape extending in the width direction of the exhaust passage 30, is provided with a drain valve 46, and is connected to the high temperature side communication pipe 24b. In addition, an outlet closing valve 48 (downstream closing means) is provided in the vicinity of the outlet header 40 of the high temperature side communication pipe 24 b, and the pressure of the heat medium between the outlet header 40 and the outlet closing valve 48. Is provided.

In the heat recovery heat exchanger 10 configured as described above, the heat medium flows into the inlet header 66 from the low temperature side communication pipe 24a and exchanges heat with the exhaust gas by flowing through each heat transfer pipe group 36. Then, the heat medium flows out from the lower header 40 to the high temperature side communication pipe 24b.
Here, the air vent valve 42 provided in the inlet header 38 can be separated into a closing valve portion 42a and a bend pipe portion 42b, and a heat medium leakage inspection (hereinafter referred to as a leak) of the heat recovery heat exchanger 10 is possible. At the time of checking), as shown in FIG. 4, a level gauge 52 is attached between the closing valve portion 42a and the bend pipe portion 42b.

The level gauge 52 has a cylindrical shape with a scale in the vertical direction, the lower end is connected to the inlet header 38 via the level gauge closing valve 54, and the removed air vent valve 42 is connected to the upper end. ing. In addition, inside the level gauge 52, an instruction plate 52a that is slidable in the vertical direction and divides the internal space in the vertical direction is provided.
Hereinafter, a leak check method for the heat recovery heat exchanger 10 according to the first embodiment of the present invention configured as described above will be described.

First, the inlet closing valve 44 is closed (upstream closing step), and the circulation of the heat medium in the gas gas heater 8 is stopped. At this time, the operation of the boiler 1 is continued.
Subsequently, the level gauge 52 is attached between the closing valve portion 42 a and the bend pipe portion 42 b in the air vent valve 42 of the inlet header 38.
Next, by opening the closing valve portion 42a, the heat medium flows into the level gauge 52 due to the pressure of the heat medium, and the indicator plate 52a rises. Then, when the indicating plate 52a is positioned at a predetermined level (for example, the vertical center position of the level gauge 52a), the closing valve portion 42a is closed.

The heat medium temperature in each heat transfer tube 36 is left for a predetermined time (for example, 1 minute) so that it becomes equal to the exhaust gas temperature.
Thereafter, the outlet closing valve 48 is closed (downstream closing step), and the closing valve portion 42a is opened. At this time, if the pressure gauge 50 is monitored and there is a sudden fluctuation such as a sudden increase in the pressure of the heating medium, the outlet closing valve 48 is opened again because the exhaust gas temperature and the heating medium temperature are still not equal. At the same time, the closing valve portion 42a is closed. The same operation is performed after a predetermined time, and the operation is repeated until the pressure is stabilized.

After the pressure is stabilized, the closing valve portion 42a is opened with the inlet closing valve 44 and the outlet closing valve 48 closed, and the indicator plate 52a is monitored (heating medium amount detecting step).
If it is left for a while and there is no change in the position of the indicator plate 52a, it is determined that no leak has occurred in the heat transfer tube group 34. On the other hand, when the indicator plate 52a continues to descend, it is determined that a heat medium leak has occurred in the heat transfer tube group 34, and the leak position is specified by visually inspecting the heat transfer tube group 34. .

Thus, by closing the inlet shutoff valve 44 and the outlet shutoff valve 48, the heat transfer medium is held in the heat transfer tube group 34, the temperature of the heat transfer tube group 34 is stabilized, and the inlet shutoff valve 44 by the level gauge 52. And a change in the amount of heat medium between the outlet closing valve 48 and the leak check.
The amount of the heat medium that enters the level gauge 52 is smaller than the amount of the heat medium stored in the heat medium storage tank 26 of the gas gas heater 8 and has an appropriate capacity for the amount of heat medium leak. It is easy to detect changes in the amount of heat medium due to heat medium leakage.

In this way, it is possible to detect a change in the amount of the heat medium in a limited portion in the heat medium path by an easy operation with the level gauge 52 attached, and to determine the change at an early stage even with a small amount of leakage.
Further, even when a heat medium leak is detected, the leak position can be specified by checking not the entire gas gas heater 8 but the heat medium path limited within the heat recovery heat exchanger 10.

From the above, it is possible to detect the leakage of the heat medium in the heat exchanger easily and early, while suppressing the deterioration of the function of the heat exchanger, and to identify the leak position, and to check the work efficiency Can be improved.
Next, a heat recovery heat exchanger 10 'according to a second embodiment of the present invention will be described.
FIG. 5 shows a schematic front view of a heat recovery heat exchanger 10 ′ according to the second embodiment of the present invention, and FIG. 6 shows a sectional view when the level gauge is attached. In the second embodiment, detailed description of the same configuration as that of the first embodiment is omitted.

As shown in FIGS. 5 and 6, the heat recovery heat exchanger 10 ′ is provided in the exhaust passage 30 ′ similar to the first embodiment.
The heat recovery heat exchanger 10 ′ is configured by a total of 24 bundles 60 in eight rows in the width direction of the exhaust passage 30 ′ and three stages of an upper stage, a middle stage, and a lower stage.
Each bundle 60 includes a heat transfer tube group 64 in which heat transfer tubes 62 are arranged in parallel, as in the bundle 32 of the first embodiment.

In addition, between the upper, middle, and lower bundles 60 of each row, upper and lower heat transfer tubes 62 are respectively connected.
In each row, one end of the heat transfer tube 62a in the upper bundle 60a is connected to the inlet header 66, and the other end of the heat transfer tube 62c in the lower bundle 60c is connected to the outlet header 68.

That is, the heat recovery heat exchanger 10 ′ in the second embodiment has eight rows of heat medium paths in parallel with the upper, middle and lower heat transfer tube groups 62 a, 62 b and 62 c as one row.
A distribution pipe 70 branched from the low-temperature side connecting pipe 24 a ″ into eight lines is connected to the inlet header 66 of each line, and an inlet closing valve 72 is provided near the inlet header 66 of each distribution pipe 70. (Upstream closing means) is provided.

Further, the inlet header 66 of each row is provided with an air vent valve 74 that can be separated into a shut-off valve portion 74a and a bend pipe portion 74b as in the first embodiment. A level gauge 76 (heat medium amount detecting means) is attached between 74a and the bend pipe portion 74b.
Each outlet header 68 is provided with a drain valve 80 and an aggregation pipe 82 is connected thereto. The aggregation pipe 82 is provided with an outlet closing valve 84 (downstream closing means) in the vicinity of the outlet header 68, and a pressure gauge 86 is provided between the outlet header 68 and the outlet closing valve 84. .

  In the heat recovery heat exchanger 10 ′ configured as described above, the heat medium is distributed into eight rows from the low temperature communication pipe 24 a ″, and flows into the inlet header 66 of each row via the distribution pipe 70, and the upper stage. The heat exchange with the exhaust gas is performed by passing through the heat transfer tube groups 62a, 62b, 62c in the middle and lower stages. Then, the heat medium flows out from the lower header 68 through the aggregation pipe 82 to the high temperature communication pipe 24 b ″.

Hereinafter, a leak check method for the heat recovery heat exchanger 10 'of the second embodiment will be described.
In the second embodiment, first, a predetermined one row (hereinafter referred to as a predetermined row) of heat medium paths for performing a leak check is selected from the eight rows of heat medium paths.
Subsequently, the same operation as the leak check method of the first embodiment is performed in the selected heat medium path of the predetermined row.

  That is, in the heat medium path of a predetermined row, the inlet stop valve 72 is closed (upstream closing process), the level gauge 76 is attached, and after a predetermined level of heat medium flows into the level gauge 76, the pressure of the heat medium is increased. Leave until is stable. After the pressure is stabilized, with the inlet closing valve 72 and the outlet closing valve 84 being closed (downstream closing step), the closing valve portion 72a is opened and the indicator plate 76a is monitored (heat medium amount detecting step).

If the indicator plate 76a continues to descend, it is determined that a heat medium leak has occurred in the predetermined row.
After the leak check in the predetermined column is completed, the heat medium path in another column is selected and the leak check is performed.
Then, the heat transfer tube groups 62a, 62b, and 62c are visually inspected only in the columns that are determined to have leaks by the leak check of each column.

Thus, the heat recovery heat exchanger 10 ′ in the second embodiment has a plurality of heat medium paths in parallel, and at the time of leak check, the leak check is performed for each column.
Therefore, in the second embodiment, the heat medium path other than the predetermined row can flow the heat medium even at the time of the leak check, and the function can be performed without reducing the heat transfer performance of the heat recovery heat exchanger 10 ′ as much as possible. Can be maintained.

Even if a leak occurs, if there is only a part of the heat recovery heat exchanger 10 ', for example, a leak point, it is only necessary to stop the heat medium circulation in the 1/8 heat medium path. The operation of the entire gas gas heater 8 can be continued while suppressing the deterioration of the function of the exchanger.
Moreover, since the leak position can be specified only by checking the 1/8 heat medium path in the heat recovery heat exchanger 10 ', the work efficiency of the check can be further improved.

Next, a heat recovery heat exchanger 10 '' according to a third embodiment of the present invention will be described.
7 to 9, FIG. 7 is a schematic front view of a heat recovery heat exchanger 10 ″ according to a third embodiment of the present invention, and FIG. 8 is a sectional view taken along line BB of FIG. FIG. 9 is a sectional view showing a leak check method according to the third embodiment. 8 and 9, the black valve indicates a closed state and the white valve indicates an open state. In the third embodiment, detailed description of the same configuration as that of the first and second embodiments is omitted.

As shown in FIGS. 7 and 8, the heat recovery heat exchanger 10 ″ is provided in the exhaust passage 30 ″ in the same manner as in the second embodiment, and has eight rows in the width direction of the exhaust passage 30 ″. It is composed of a total of 24 bundles 90 in three stages, an upper stage, a middle stage and a lower stage.
And each bundle 90 is equipped with the heat-transfer tube group 94 in which the heat-transfer tube 92 was arranged in parallel like the said 1st Example, and the inlet to which the end of the heat-transfer tube 92 was connected for every bundle 90 An outlet header 98 to which the header 96 and the other end of the heat transfer tube 92 are connected is provided.

Further, between the upper, middle and lower bundles 90 in each row, the outlet header 98a of the upper bundle 90a, the inlet header 96b of the middle bundle 90b, the outlet header 98b of the middle bundle 90b and the inlet header 96c of the lower bundle 90c are connected. The tubes 100 and 102 are connected.
Furthermore, the distribution header 104 branched from the low-temperature side connecting pipe 24a ″ into the eight rows is connected to the inlet header 96a of the upper bundle 90a of each row, and the outlet header 98c of the lower bundle 90c is connected to the outlet header 98c. An aggregation pipe 106 connected to the high temperature side communication pipe 24b '' is connected.

Further, in each row, a bypass pipe (detour path) connected from the distribution pipe 104 to each of the connection pipes 100 and 102 and the aggregation pipe 106 is provided.
The distribution pipes 104, the connecting pipes 100 and 102, and the collecting pipes 106 connected to the inlet header 96 and the outlet header 98 of each bundle 90 are each provided with a closing valve 110 (upstream closing means, downstream side) at a corresponding header vicinity position. Closing means, intermediate closing means) are provided. That is, in each bundle 90, the stop valve 110 is provided at the inlet and outlet of the heat medium.

Further, the bypass pipe 108 is provided with bypass stop valves 112 at the upper, middle, and lower stages so as to be located between the distribution pipe 104, the connecting pipes 100 and 102, and the aggregation pipe 106.
Thus, the heat exchanger 10 ″ for heat recovery in the third embodiment has eight rows of heat medium paths in parallel with the upper, middle, and lower heat transfer tube groups 94a, 94b, 94c as one row. In addition, each stage is configured to be independent from the heat medium path.

  In addition, an air vent valve 114 is provided at the inlet header 96 of each bundle 90, and a drain valve 116 is provided at the outlet header 98. Note that the air vent valve 114 of the inlet header 98a of the upper bundle 90a of each row can be separated into the shut-off valve 114a and the bend pipe 114b as in the first and second embodiments, and at the time of leak check, the shut-off valve 114a. And a level gauge 118 can be mounted between the bend pipes 114b.

A pressure gauge 120 is provided between the outlet header 98c of the lower bundle 90c and the corresponding stop valve 110.
Hereinafter, a leak check method for the heat recovery heat exchanger 10 ″ of the third embodiment will be described.
First, as shown in FIG. 9 (a), with all the bypass stop valves 112 closed, one row of heating medium paths for performing a leak check is selected from the eight rows of heating medium paths, and the second embodiment described above. In the same procedure as above, a leak check is performed on the heat medium path in a predetermined row.

Subsequently, in the predetermined row, when it is determined that the indicator plate 118a of the level gauge 118 continues to descend and a leak has occurred, from the closing valve 110 at the heat medium inlet of the lower bundle 90c, the middle bundle 90b The closing valves 110 and 110 at the heating medium outlet and the heating medium inlet and the closing valve 110 at the heating medium outlet of the upper bundle 90a are closed in this order (intermediate closing step).
As shown in FIG. 9B, when the lowering of the indicator plate 118a in the level gauge 118 stops immediately after closing the closing valve 110 at the heating medium inlet of the middle bundle 90b, the heating medium inlet of the middle bundle 90b and It can be determined that there is a leaking place in the heat transfer tube group 94b between the outlet of the heat medium.

After the leaking bundle is identified in this way, as shown in FIG. 9 (c), the heating medium inlet and heating medium outlet closing valves 110, 110 of the leaking middle-stage bundle 90b are closed, and the other closing is performed. The valve 110 opens. Further, the bypass closing valve 112b in the middle stage of the bypass pipe 108 is opened (a bypassing step). That is, the middle bundle 90b is made independent from the heat medium path.
Therefore, the heat medium that has passed through the heat transfer tube group 94a in the upper bundle 90a is guided to the bypass pipe 108, bypasses the heat transfer tube group 94a in the middle bundle 90b, and flows into the heat transfer tube group 94c in the lower bundle 90c. To do.

After performing a leak check on each row in this manner, only the heat transfer tube group 94 of the bundle 90 determined to have a leak is visually inspected.
In this way, the heat recovery heat exchanger 10 '' in the third embodiment has a plurality of heat medium paths in parallel, and the heat medium paths can be independent of the bundles 90 in a plurality of stages in the row. Yes, at the time of leak check, the leak check area can be narrowed down to the bundle unit.

  As a result, the same effects as those of the first and second embodiments can be obtained, and the leaking part can be specified in units of bundles. Even after the leaking part is specified, the leaking part can be identified via the bypass pipe 108. By detouring the bundle, the function can be maintained without reducing the heat transfer performance of the heat exchanger during the boiler operation as much as possible. For example, if there is only one leak location, it is only necessary to stop the circulation of the heat medium in the 1/24 heat medium path, and it is possible to suppress the heat transfer performance of the heat exchanger from decreasing more than in the second embodiment. .

Although the description about the embodiment of the heat medium leakage inspection device and the heat medium inspection method of the heat exchanger according to the present invention is finished above, the embodiment is not limited to the above embodiment.
For example, the heat exchanger in the above embodiment is the heat exchanger for heat recovery 10, 10 ′, 10 ″ of the gas gas heater 8, but is not limited to the heat exchanger. For example, the present invention can be applied to a heat exchanger for reheating a gas gas heater or a heat exchanger other than a gas gas heater.

In addition, the heat exchanger in the above embodiment is a so-called vertical heat exchanger, but the arrangement of the heat exchanger is not limited to this, and for example, a so-called horizontal heat exchanger is also applicable. .
In the above embodiment, the level gauges 52, 76, 118 are provided in the inlet headers 38, 66, 96, but the level gauges 52, 76, 118 are provided on the upstream side of the heating medium and the downstream side of the heating medium. What is necessary is just to be provided between the stop valve in the side, and it is not restricted to what is provided in this position.

Moreover, in the said 2nd and 3rd Example, although comprised from 24 bundles 60 and 90, the number of bundles etc. are not restricted to this.
In the third embodiment, the stop valve 110 is provided at each of the heat medium inlet and the heat medium outlet of each bundle 90. However, if the intermediate closing means can narrow the region for detecting the amount of the heat medium in the heat medium path. For example, the connection pipes 100 and 102 may be provided with one stop valve.

It is a schematic block diagram of the waste gas processing apparatus provided with the heat-medium leakage inspection apparatus of the heat exchanger which concerns on this invention. It is a front schematic diagram of the heat exchanger for heat recovery concerning the 1st example of the present invention. It is sectional drawing which follows the AA line of FIG. It is sectional drawing at the time of level gauge attachment of the heat exchanger for heat recovery which concerns on 1st Example of this invention. It is a schematic front view of the heat exchanger for heat recovery according to the second embodiment of the present invention. It is sectional drawing at the time of level gauge attachment of the heat exchanger for heat recovery which concerns on 2nd Example of this invention. It is a schematic front view of the heat exchanger for heat recovery according to the third embodiment of the present invention. It is sectional drawing which follows the BB line of FIG. It is sectional drawing which shows the leak check method of 3rd Example.

Explanation of symbols

1 Boiler 8 Gas Gas Heater 10, 10 ', 10 "Heat Recovery Heat Exchanger 18 Reheating Heat Exchanger 24a, 24a', 24a '' Low Temperature Side Connection Tube (Heat Medium Path)
24b, 24b ', 24b''High-temperature side communication pipe (heat medium path)
26 Heat storage tank 28 Circulation pump 30, 30 ′ Exhaust gas passage 34, 64, 94 Heat transfer tube group 36, 62, 92 Heat transfer tube (heat medium path)
38, 66, 96 Inlet header 40, 68, 98 Outlet header 42, 74, 114 Air vent valve 42a, 74a, 114a Stop valve part 42b, 74b, 114b Bend pipe part 44, 72 Inlet stop valve (upstream closing means)
48, 84 Outlet closing valve (downstream closing means)
50, 86, 120 Pressure gauge 52, 76, 118 Level gauge (heat medium detection means)
60, 90 Bundle 70, 104 Distribution pipe (heat medium path)
82 Aggregation pipe (heat medium path)
100, 102 Connecting pipe 108 Bypass pipe (detour path)
110 Closing valve (upstream closing means, downstream closing means, intermediate closing means)
112 Bypass stop valve

Claims (9)

In the heat exchanger leakage inspection device of the heat exchanger that inspects the leakage of the heat carrier in the heat exchanger having the heat medium path through which the heat medium flows,
An upstream closing means provided in an upstream portion of the heating medium path and blocking the heating medium path;
A downstream closing means provided at a downstream portion of the heat medium path of the heat medium path and blocking the heat medium path;
When the heat medium path is blocked by the upstream closing means and the downstream closing means, a heat medium amount detecting means for detecting a change in the amount of the heat medium between the upstream closing part and the downstream closing part in the heat medium path;
A heat medium leakage inspection device for a heat exchanger, comprising: The heat exchanger has a plurality of the heat medium paths in parallel,
The upstream closing means is provided in the heat medium upstream portion of each row of the heat medium path,
The downstream closing means is provided in the heat medium downstream portion of each row of the heat medium path,
When the heat medium path of a predetermined row is blocked by the upstream closing means and the downstream closing means, the heat medium amount detecting means is provided between the upstream closed portion and the downstream closed portion in the heat medium path of the predetermined row. The heat medium leakage inspection apparatus for a heat exchanger according to claim 1, wherein a fluctuation in the amount of the heat medium is detected.   An intermediate closing means is provided between the upstream closing portion and the downstream closing portion of the heating medium path, wherein the heating medium path is blocked at a predetermined position so as to narrow a region for detecting the amount of the heating medium. Item 3. A heat medium leakage inspection device for a heat exchanger according to Item 1 or 2.   4. The heat exchanger according to claim 1, further comprising a detour path that detours a region in which the amount of the heat medium detected by the heat medium amount detection unit fluctuates in the heat medium path. Heat medium leakage inspection device.   5. The heat exchanger leakage inspection device for a heat exchanger according to claim 1, wherein the heat exchanger is provided in an exhaust gas passage of a combustion device and performs heat exchange with the exhaust gas. . In the heat medium leakage inspection method of the heat exchanger for inspecting the leakage of the heat medium in the heat exchanger having the heat medium path through which the heat medium flows,
An upstream closing step of blocking the heat medium path at a heat medium upstream part of the heat medium path;
A downstream closing step of blocking the heat medium path at a heat medium downstream part of the heat medium path;
After the upstream closing step and the downstream closing step, a change in the amount of the heat medium between the upstream closing portion closed in the upstream closing step and the downstream closing portion closed in the downstream closing step in the heating medium path is detected. A heating medium amount detecting step to perform,
A heat medium leakage inspection method for a heat exchanger, comprising: The heat exchanger has a plurality of the heat medium paths in parallel,
In the upstream closing step, the heat medium path is interrupted at a heat medium upstream portion of a predetermined row of the heat medium path,
In the downstream closing means, the heat medium path is interrupted at the downstream portion of the heat medium in a predetermined row of the heat medium path,
In the heat medium amount detecting step, after the upstream closing step and the downstream closing step, an upstream closing portion closed in the upstream closing step and a downstream closed in the downstream closing step in the heating medium path of the predetermined row. The method of inspecting a heat medium leakage of a heat exchanger according to claim 6, wherein a change in the amount of the heat medium between the closed portions is detected.   While detecting fluctuations in the amount of heat medium in the heat medium amount detecting step, between the upstream closed portion closed in the upstream closing step of the heat medium path and the downstream closed portion closed in the downstream closing step, 8. The heat medium leakage inspection method for a heat exchanger according to claim 6 or 7, further comprising an intermediate closing step of interrupting the heat medium path at a predetermined position so as to narrow a region for detecting the amount of heat medium.   The heat medium leakage inspection method for a heat exchanger according to claim 6 or 8, further comprising a detour step of detouring a region where the amount of the heat medium detected in the heat medium amount detection step fluctuates.

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