JP4240693B2 - Condenser - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a condenser, and more particularly, to a condenser that can improve reliability against ammonia attack and improve heat transfer performance even if it has a copper-based cooling pipe.
[0002]
[Prior art]
FIG. 8 is a longitudinal sectional view schematically showing a main part of a condenser according to Japanese Patent Application No. 10-176160 filed by the present applicant. A cooling pipe group 1 for condensing the steam S discharged from the steam turbine is disposed in a trunk body (not shown). The cooling pipe group 1 is composed of a number of cooling pipes made of, for example, copper-based metal and extending in parallel with each other in the horizontal direction. The upper pipe group 1a and the lower pipe are separated by a partition plate 2 as a horizontal tray. It is an integrated type partitioned into a group 1b. And this cooling pipe group 1 makes the side part outline shape of the upper pipe group 1a into the inclined shape which has a gradient which becomes narrow as it goes upwards from the partition plate 2, and the side part of the lower pipe group 1b. The outer shape is formed so that the width of the lowermost end is the narrowest.
[0003]
The air moving passage 3 extends in the center of the cross section of the upper tube group 1a and the lower tube group 1b in the tube axis direction of the cooling tube so that the cross-sectional shape is a plate shape. The air extraction unit 4 is provided in the middle of the air movement passage 3 and communicates with an air extractor (not shown). Further, the steam flow path leading to the air extraction unit 4 is narrowed as a whole, and the decrease in the flow rate as the steam condenses is reduced. The air movement passage 3 extends through the air extraction unit 4 further downward.
[0004]
In the condenser thus formed, the low-pressure steam S at the outlet of the steam turbine flows into the upper tube group 1a and the lower tube group 1b. Since the upper tube group 1a and the lower tube group 1b are formed in the above-described gradient shape, the flow of steam at the outer periphery of the tube groups 1a and 1b is equalized, the static pressure distribution becomes constant, and the tube group Steam flows into the tube groups 1a and 1b uniformly from the outer periphery of 1a and 1b.
[0005]
The steam that has flowed through the upper tube group 1a and the lower tube group 1b is condensed by exchanging heat with the cooling water in the cooling tube to become condensed drain water, and the condensed drain water having a high density flows down outside the tube group. . Further, the air contained in the steam flows from the upper tube group 1a and the lower tube group 1b into the air moving passage 3 and is cooled by the air extraction unit 4, and then the air moving passage 3 is moved in the tube axis direction. To be discharged into the atmosphere.
[0006]
[Problems to be solved by the invention]
However, although the steam flow path leading to the air extraction unit 4 is narrowed as a whole and the flow rate is reduced as the steam condenses, the final condensing is the final point where the steam condenses. In the vicinity of the part 5, the flow rate is reduced because the amount of steam is reduced, and a flow staying part (high air concentration part) is locally generated. As a result, an air (non-condensable gas) pool is generated, and a cooling pipe that does not contribute to condensation heat transfer is formed, so that the condensate performance is deteriorated and ammonia attack (corrosion) can occur.
[0007]
On the other hand, in order to cope with such ammonia attack, a means for forming the cooling pipe with a material having excellent corrosion resistance such as titanium is also employed, but this increases the cost and has the same heat transfer performance. Compared to the above, there is a problem that the strength is lowered.
[0008]
The present invention has been made in view of the above, and an object of the present invention is to provide a condenser capable of improving the reliability against ammonia attack in a copper-based cooling pipe and improving heat transfer performance.
[0009]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, a condenser according to claim 1 of the present invention includes an upper tube group disposed on an upper portion of the horizontal tray with respect to a horizontally installed horizontal tray, and the horizontal tray. A lower tube group disposed in a lower portion of the upper tube group, an air movement passage penetrating through a central portion of the upper tube group and the lower tube group, and air contained in the steam provided in communication with the air movement passage. And a flow rate holding means for holding the flow rate of the steam that reaches the air extraction unit through the upper tube group and the lower tube group, and the flow of the steam stays in both the tube groups. parts are all SANYO which is adapted to prevent the occurrence, the flow rate holding means, steam a said air extractor vicinity to hold the flow rate or constant at the final condensation section near the final point to condense A flow path adjustment plate that forms a narrow flow path section for Rutotomoni, comprising a small hole forming plate having a small hole for passing the steam through the narrow flow path portion, and is provided with a plurality of small holes in the flow path adjustment plate.
[0010]
The steam that has flowed in the upper and lower tube groups is condensed by exchanging heat with the cooling water in the cooling pipes, and becomes condensed drain water and air. The dense condensed drain water flows down to the outside of the pipe group. Fall into the hot well. The steam and air that have passed through the upper tube group and the lower tube group reach the air extraction unit while the flow rate is maintained by the flow rate holding unit. In the flow rate holding means, the steam and air that have passed through the upper tube group and the lower tube group are guided to the narrow channel part by the channel adjusting plate, and pass through the small hole of the small hole forming plate while maintaining a flow rate above a certain level. To do. Thereby, it can avoid that an airflow speed falls remarkably and can ensure the safety | security with respect to generation | occurrence | production of an air pocket.
[0011]
Therefore, a significant decrease in the flow velocity that has conventionally occurred in the final condensing part and the occurrence of a flow retaining part accompanying this are prevented. As a result, the concentration of air (non-condensable gas) contained in the steam can be prevented from being increased, the condensation heat transfer coefficient can be prevented from being lowered, and the cooling pipe is made of a copper-based metal. Ammonia attack is less likely to occur.
[0015]
Moreover, the flow rate holding means, since is provided with a plurality of small holes in the flow path adjustment plate, it is possible to prevent the occurrence of retention of the flow in the flow path adjustment plate near, the generation of ammonia attack in the region Therefore, the reliability against ammonia attack can be further improved.
[0016]
In addition, an upper tube group disposed at the upper part of the horizontal tray with respect to the horizontally installed horizontal tray, a lower tube group disposed at the lower part of the horizontal tray, the upper tube group, and the lower tube An air moving passage penetrating in a central portion of the group, and an air extracting portion provided in communication with the air moving passage for extracting air contained in the steam, and further comprising the upper tube group and the lower tube group. It is provided with a flow rate holding means for holding the flow rate of the steam passing through to the air extraction part, and prevents the staying part of the steam flow from occurring in both the tube groups, the flow rate holding means , it is provided with a plurality of flow path adjustment plate forming one of the narrow flow path portion of the steam to a said air extractor vicinity to hold the flow rate or constant at the final condensation section near the final point to condense Good. The steam and air that have passed through the upper tube group and the lower tube group are guided to the narrow channel portion by the plurality of channel adjustment plates and reach the air extraction unit.
[0017]
At this time, if the channel area of the narrow channel part is set to match the gas phase flow rate, the air flow rate can be maintained at a certain level or more, and a significant decrease in the flow rate that has conventionally occurred in the final condensing part and the accompanying flow Occurrence of the stagnant portion is prevented. Therefore, it is possible to prevent the concentration of air (non-condensable gas) contained in the vapor from increasing, prevent the condensation heat transfer coefficient from decreasing, and even if the cooling pipe is made of copper-based metal, ammonia Attacks are less likely to occur.
[0018]
Incidentally, the flow rate holding means may it der those formed by a perforated plate provided in the vicinity of the air extraction unit. The steam and air that have passed through the upper tube group and the lower tube group are rectified by the perforated plate, the flow velocity distribution is made uniform, and the air extraction unit is reached. At this time, since the flow velocity distribution is made uniform, there is no portion where the flow rate is remarkably lowered, and a significant flow velocity drop that has conventionally occurred in the final condensing portion and the accompanying flow retention portion are prevented.
[0019]
Further, the flow rate holding means may it der those formed so as not to place a portion of the cooling tube in the vicinity of the air extraction unit. Thereby, while reducing the number of parts, the flow velocity distribution can be made uniform, the flow velocity at that portion can be significantly reduced, and the occurrence of a flow retention portion can be prevented. Further, the reliability against ammonia attack can be improved.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a condenser according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.
[0021]
(Embodiment 1)
1 is a longitudinal sectional view showing the vicinity of an air extraction portion of a condenser according to Embodiment 1 of the present invention. In the following description, members that are the same as or correspond to those already described are assigned the same reference numerals, and redundant description is omitted.
[0022]
The flow path adjusting plate 6 forms the narrow flow path portions 7 and 8, and is disposed in the vicinity of the air extraction portion 4, that is, in the vicinity of the above-described final condensing portion 5 in order to guide the vapor to the small hole 9 described later. It has been done. Both end portions of the flow path adjusting plate 6 are respectively fixed to tube support plates (not shown) disposed to support the upper tube group 1a and the lower tube group 1b. The flow path adjusting plate 6 is formed of, for example, a carbon steel plate.
[0023]
Similarly to the flow path adjusting plate 6, the small hole forming plate 10 fixed to a tube support plate (not shown) has a small hole 9 at the center for allowing the vapor passing through the narrow flow path portions 7 and 8 to pass therethrough. Yes. The small holes 9 can be formed as so-called orifices, and the number of the small holes 9 is determined in consideration of the extraction flow rate to be set. The small hole forming plate 10 is formed of, for example, a carbon steel plate.
[0024]
In the condenser thus formed, the steam that has flowed in the upper tube group 1a and the lower tube group 1b is condensed by exchanging heat with the cooling water in the cooling tube, and becomes condensed drain water and air. Large condensed drain water flows down outside the tube group and falls into a hot well (not shown).
[0025]
The steam and air that have passed through the upper tube group 1 a and the lower tube group 1 b are guided to the narrow channel portions 7 and 8 by the channel adjusting plate 6 and pass through the small holes 9 of the small hole forming plate 10. At this time, by appropriately selecting the flow path cross-sectional areas of the narrow flow path portions 7 and 8, the occurrence of a significant low flow rate portion is avoided, and a significant decrease in flow rate that has conventionally occurred in the final condensing unit 5 and the flow accompanying this. Occurrence of the stagnant portion is prevented.
[0026]
Therefore, it is possible to prevent the concentration of air (non-condensable gas) contained in the steam from increasing, prevent the condensation heat transfer coefficient from decreasing, and even if the cooling pipe is formed of a copper-based metal, Ammonia attack is less likely to occur.
[0027]
Air flows from the upper tube group 1a and the lower tube group 1b into the air moving passage 3, flows through the final condensing unit 5 through the air extraction unit 4 in the direction of the tube axis, and is discharged into the atmosphere.
[0028]
As described above, according to the condenser according to the first embodiment, with a simple structure, a significant reduction in the flow velocity that has conventionally occurred in the final condensing unit 5 and the occurrence of a flow retaining part accompanying this are prevented. it can. Therefore, it is possible to prevent the concentration of air (non-condensable gas) contained in the steam from being increased, prevent the condensation heat transfer rate from being lowered, and even if the cooling pipe is formed of a copper-based metal, Ammonia attack is less likely to occur and the reliability of the device can be improved.
[0029]
In Embodiment 1 described above, the cooling pipe is described as being formed of a copper-based metal. However, the present invention is not limited to this. For example, a copper-based metal cooling pipe with nickel plating is used. As a result, the reliability against ammonia attack can be further improved. Similarly, the flow path adjusting plate 6 may be plated. In that case, it is preferable that both the cooling pipe and the flow path adjusting plate 6 are formed of the same material.
[0030]
(Embodiment 2)
2 is a perspective view showing a flow path adjusting plate of a condenser according to a second embodiment of the present invention, and FIG. 3 is a perspective view showing another flow path adjusting plate. In the second embodiment, as shown in FIG. 2, a plurality of square holes 12 are provided in the flow path adjusting plate 6 shown in the first embodiment, or, as shown in FIG. By providing a plurality of round holes 13 in the flow path adjusting plate 6 shown in FIG. 6, it is possible to prevent the occurrence of a staying part of the flow in the vicinity of the flow path adjusting plate 6 and to prevent the occurrence of ammonia attack at the site. It is what. The diameter and number of the square holes 12 and the round holes 13 are determined in consideration of the flow rate to be set. Needless to say, the hole shape is not limited to the above shape.
[0031]
In the condenser thus formed, the steam and air that have passed through the upper tube group 1a and the lower tube group 1b are guided to the narrow flow channel portions 7 and 8 by the flow channel adjusting plate 6 and a part of the steam. Etc. pass directly through the square holes 12 (or round holes 13) and through the small holes 9 of the small hole forming plate 10. Subsequent operations are the same as those in the first embodiment, and a duplicate description is omitted.
[0032]
As described above, according to the condenser according to the second embodiment, in addition to the same effects as the first embodiment, it is possible to prevent the occurrence of a staying part of the flow in the vicinity of the flow path adjusting plate 6, Since the occurrence of ammonia attack at the part can be prevented, the reliability against ammonia attack can be further improved.
[0033]
(Embodiment 3)
FIG. 4 is a longitudinal sectional view showing the vicinity of the air extraction portion of the condenser according to the third embodiment of the present invention. The flow path adjusting plates 14 and 15 are disposed in the vicinity of the air extraction section 4, that is, in the vicinity of the final condensing section 5 described above, in order to form the narrow flow path section 16. Both end portions of the flow path adjusting plates 14 and 15 are respectively fixed to tube support plates (not shown) disposed to support the upper tube group 1a and the lower tube group 1b. Further, a drain hole (not shown) is provided at the lower end of the flow path adjusting plate 15. These flow path adjusting plates 14 and 15 are formed of, for example, a carbon steel plate.
[0034]
In the condenser thus formed, the steam and air that have passed through the upper tube group 1a and the lower tube group 1b are guided to the narrow flow channel portion 16 by the flow channel adjusting plates 14 and 15, and are sent to the air extraction unit 4. It reaches. At this time, by appropriately selecting the flow passage area of the narrow flow passage portion 16, it is possible to avoid the occurrence of a portion where the flow velocity is remarkably lowered, and the significant reduction in the flow velocity conventionally generated in the final condensing portion 5 and Occurrence of the accompanying flow retention is prevented. Therefore, it is possible to prevent the concentration of air (non-condensable gas) contained in the steam from increasing, prevent the condensation heat transfer coefficient from decreasing, and even if the cooling pipe is formed of a copper-based metal, Ammonia attack is less likely to occur.
[0035]
As described above, according to the condenser according to the third embodiment, a simple structure prevents a significant decrease in the flow velocity that has conventionally occurred in the final condensing unit 5 and the occurrence of a flow retention part associated therewith. it can. Therefore, it is possible to prevent the concentration of air (non-condensable gas) contained in the steam from being increased, prevent the condensation heat transfer rate from being lowered, and even if the cooling pipe is formed of a copper-based metal, Ammonia attack is less likely to occur and the reliability of the device can be improved.
[0036]
(Embodiment 4)
FIG. 5 is a longitudinal sectional view showing the vicinity of an air extraction unit of a condenser according to Embodiment 4 of the present invention. The perforated plate 17 is disposed in the vicinity of the air extraction unit 4, that is, in the vicinity of the final condensing unit 5 described above. Both end portions of the perforated plate 17 are fixed to a tube support plate (not shown) arranged to support the upper tube group 1a and the lower tube group 1b. The porous plate 17 is formed of, for example, a carbon steel plate.
[0037]
In the condenser thus formed, the steam and air that have passed through the upper tube group 1 a and the lower tube group 1 b are rectified by the perforated plate 17 and reach the air extraction unit 4. At this time, since the flow velocity distribution is made uniform, the occurrence of a remarkably low flow velocity portion can be avoided, and the significant decrease in the flow velocity that has conventionally occurred in the final condensing portion 5 and the accompanying occurrence of a flow retention portion are prevented. . Therefore, it is possible to prevent the concentration of air (non-condensable gas) contained in the steam from increasing, prevent the condensation heat transfer coefficient from decreasing, and even if the cooling pipe is formed of a copper-based metal, Ammonia attack is less likely to occur.
[0038]
As described above, according to the condenser according to the fourth embodiment, with a very simple structure, a significant reduction in the flow velocity that has conventionally occurred in the final condensing unit 5 and the generation of a staying part of the flow associated therewith can be achieved. Can be prevented. Therefore, it is possible to prevent the concentration of air (non-condensable gas) contained in the steam from being increased, prevent the condensation heat transfer rate from being lowered, and even if the cooling pipe is formed of a copper-based metal, Ammonia attack is less likely to occur and the reliability of the device can be improved.
[0039]
(Embodiment 5)
FIG. 6 is a longitudinal sectional view showing the vicinity of an air extraction portion of a condenser according to Embodiment 5 of the present invention. In the invention according to the fifth embodiment, the cooling pipe non-arranged portion 18 is formed in the vicinity of the air extraction unit 4, that is, in the vicinity of the final condensing unit 5 described above without arranging a part of the cooling pipe. The flow velocity distribution is made uniform to prevent a significant decrease in the flow velocity at the portion and the occurrence of a flow retention portion.
[0040]
As a result, the same effects as in the case of the fourth embodiment can be achieved while reducing the number of parts. In addition, it is also possible to adjust to a desired flow velocity distribution by appropriately providing a perforated plate in the cooling pipe non-arranged portion 18.
[0041]
(Embodiment 6)
FIG. 7: is a longitudinal cross-sectional view which shows the air extraction part vicinity of the condenser concerning Embodiment 6 of this invention. The first to fifth embodiments are configured by disposing the flow path adjusting plate 6 or the like in the portion without disposing some of the cooling tubes disposed at the same pitch. In contrast to this, in the sixth embodiment, the cooling pipe arrangement pitch of the cooling pipe group indicated by the oblique lines in the figure is appropriately changed and adjusted, and the small hole forming plate 10 having the small holes 9 is arranged. By installing, the flow velocity distribution is made uniform, and the occurrence of a flow retention portion is prevented. As a result, the same effects as those of the fourth embodiment can be obtained.
[0042]
【The invention's effect】
As described above, according to the condenser according to the present invention (Claim 1), the upper tube group disposed at the upper part of the horizontal tray with the horizontally installed horizontal tray as a boundary, and the horizontal tray A lower tube group disposed in a lower portion of the upper tube group, an air movement passage penetrating through a central portion of the upper tube group and the lower tube group, and air contained in the steam provided in communication with the air movement passage. And a flow rate holding means for holding the flow rate of the steam that reaches the air extraction unit through the upper tube group and the lower tube group, and the flow of the steam stays in both the tube groups. The flow rate holding means is for holding the flow rate above a certain level in the vicinity of the final condensing part, which is the final point where the steam condenses near the air extracting part. Provided with a flow path adjustment plate that forms a narrow flow path section Since both provided with small holes formed plate having a small hole for passing the steam through the narrow flow path portion, it can prevent the residence of the flow of steam in the two pipe groups occurs, the condensation heat transfer Condensation performance can be improved because it is possible to prevent the formation of a cooling pipe that does not contribute to heat. Moreover, since the generation | occurrence | production of the stay part of the said flow can be prevented, even if it is provided with the copper-type cooling pipe, the reliability with respect to an ammonia attack can be improved. In addition, since the flow path adjusting plate is provided with a plurality of small holes, it is possible to prevent the occurrence of a stagnation part of the flow in the vicinity of the flow path adjusting plate, to prevent the occurrence of ammonia attack at the site, and further against the ammonia attack. Reliability can be improved.
[0045]
Further, the upper tube group arranged on top of the horizontal tray with horizontal installed and the horizontal tray border, the lower tube group arranged on the bottom of the horizontal tray, the upper tube group and the lower An air moving passage penetrating through the central portion of the tube group, and an air extracting portion that communicates with the air moving passage and extracts air contained in the steam, and further passes through the upper tube group and the lower tube group. A flow rate holding means for holding the flow rate of the steam reaching the extraction unit is provided, and this flow rate holding unit holds the flow rate above a certain level in the vicinity of the final condensing unit, which is the final point where the vapor condenses near the air extracting unit. one lever comprises a plurality of flow path adjustment plate forming a narrow flow path portion, can prevent the residence of the steam flow occurs during tube bundle, can cooling tube that does not contribute to the condensation heat transfer Condensation performance can be improved and copper can be prevented. It is a structure having a cooling tube, thereby improving the reliability of the ammonia attack.
[0046]
If the flow rate holding means is formed by providing a porous plate in the vicinity of the air extraction part, it is possible to prevent the generation of a stagnant part of the steam flow in the tube group with a simpler structure, contributing to condensation heat transfer. It is possible to prevent a cooling pipe from being formed. Therefore, the condensation performance can be improved, and the reliability against ammonia attack can be improved even if a copper cooling pipe is provided.
[0047]
Further, the flow rate holding means, be formed so as not to place a portion of the cooling tube in the vicinity of the air extraction unit, can be easily equalized flow velocity distribution, the residence of the steam flow occurs during tube bank Therefore, the reliability against ammonia attack can be improved even with a copper-based cooling pipe.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing the vicinity of an air extraction unit of a condenser according to a first embodiment of the present invention.
FIG. 2 is a perspective view showing a flow path adjusting plate of a condenser according to a second embodiment of the present invention.
FIG. 3 is a perspective view showing another flow path adjusting plate.
FIG. 4 is a longitudinal sectional view showing the vicinity of an air extraction unit of a condenser according to a third embodiment of the present invention.
FIG. 5 is a longitudinal sectional view showing the vicinity of an air extraction unit of a condenser according to a fourth embodiment of the present invention.
FIG. 6 is a longitudinal sectional view showing the vicinity of an air extraction unit of a condenser according to a fifth embodiment of the present invention.
FIG. 7 is a longitudinal sectional view showing the vicinity of an air extraction unit of a condenser according to a sixth embodiment of the present invention.
FIG. 8 is a longitudinal sectional view schematically showing a main part of a conventional condenser.
[Explanation of symbols]
S Steam 1 Cooling tube group 1a Upper tube group 1b Lower tube group 2 Partition plate 3 Air movement passage 4 Air extraction unit 5 Final condensing units 6, 14, 15 Channel adjustment plates 7, 8, 16 Narrow channel unit 9 Small hole 10 small hole forming plate 12 square hole 13 round hole 17 perforated plate 18 cooling pipe non-arranged portion

Claims (1)

An upper tube group disposed at the upper part of the horizontal tray, with the horizontal tray set as a boundary,
A lower tube group disposed at a lower portion of the horizontal tray;
An air movement passage penetrating in a central portion of the upper tube group and the lower tube group;
An air extraction unit that is provided in communication with the air movement passage and extracts air contained in the steam;
In the condenser with
It is provided with a flow rate holding means for holding the flow rate of the steam that reaches the air extraction section through the upper tube group and the lower tube group, and prevents the generation of the stay portion of the steam flow in both the tube groups. ,
The flow rate holding means includes a flow path adjusting plate that forms a narrow flow path portion for holding a flow rate at a certain level or more near the final condensing portion that is in the vicinity of the air extraction portion and is the final point where the steam is condensed. A condenser comprising a small hole forming plate having small holes through which steam passing through the narrow flow channel portion is passed, and a plurality of small holes provided in the flow channel adjusting plate.

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