JP2018194185A - Drain recovery system - Google Patents

Abstract

To reduce occurrence of a water hammer.SOLUTION: A drain recovery system 1 includes: a first drain pipe 14 in which drain circulates; and a second drain pipe 16 which causes drain having a temperature higher than that of the drain circulating in the first drain pipe 14 to flow into the first drain pipe 14. The second drain pipe 16 causes the drain to flow into a position of the first drain pipe 14 which is located below an axis center X of the first drain pipe 14.SELECTED DRAWING: Figure 3

Description

  The technology disclosed herein relates to a drain recovery system.

  Conventionally, a drain recovery system for recovering drain is known. For example, Patent Document 1 discloses a system including a first drain pipe (collection main pipe) through which drain flows and a second drain pipe (branch collection pipe) that allows the drain to flow out to the first drain pipe. .

JP 50-55701 A

  By the way, in the system as described above, the drain flowing through the second drain pipe may re-evaporate. And when the temperature of the drain which distribute | circulates a 2nd drain pipe is higher than the temperature of the drain which distribute | circulates a 1st drain pipe, the re-evaporated vapor | steam which flowed out from the 2nd drain pipe to the 1st drain pipe may condense abruptly. When the re-evaporated vapor condenses abruptly, an impact or sound is generated. A phenomenon in which a large impact or sound is generated by the rapid condensation of steam is called water hammer.

  The technology disclosed herein has been made in view of such circumstances, and an object thereof is to reduce the occurrence of water hammer.

  The drain recovery system disclosed herein includes a first drain pipe through which drain flows, and a second drain pipe through which drain having a temperature higher than that of the drain flowing through the first drain pipe flows out to the first drain pipe. The second drain pipe causes the re-evaporated vapor of the drain to flow out of the first drain pipe at a position below the axial center of the first drain pipe.

  According to the drain recovery system, the generation of water hammer can be reduced.

FIG. 1 is a piping diagram of a drain recovery system. FIG. 2 is a cross-sectional view of the first drain pipe at the connection portion of the second drain pipe. FIG. 3 is a longitudinal sectional view of the first drain pipe at the connection portion of the second drain pipe. It is. FIG. 4 is a vertical cross-sectional view of the first drain pipe at the connection portion of the second drain pipe according to the modification. FIG. 5 is a vertical cross-sectional view of the first drain pipe at the connection portion of the second drain pipe according to another modification.

  Hereinafter, embodiments of the present application will be described with reference to the drawings. Note that the following embodiments are essentially preferable examples, and are not intended to limit the scope of the technology disclosed in the present application, applications thereof, or uses thereof.

  FIG. 1 is a piping diagram of the drain recovery system 1. As shown in FIG. 1, the drain recovery system 1 circulates a steam pipe 11 through which steam flows, a steam using device 13 to which steam is supplied via the steam pipe 11, and a drain discharged from the steam using device 13. And a plurality of second drain pipes 16 through which drain generated in the steam pipe 11 flows out to the first drain pipe 14. The drain recovery system 1 recovers the drain generated in the steam using device 13 and the drain generated in the steam pipe 11.

  The upstream end of the steam pipe 11 is connected to, for example, boiler equipment (not shown). The downstream end of the steam pipe 11 is connected to the steam using device 13. Steam generated in the boiler facility is supplied to the steam using device 13 through the steam pipe 11. The pressure of the steam flowing through the steam pipe 11 is higher than the atmospheric pressure. The steam pipe 11 is provided with a pressure reducing valve 12 for adjusting the pressure of the steam. The steam using device 13 is, for example, a heat exchanger. In the steam using device 13, the steam supplied from the steam pipe 11 dissipates heat to the object and condenses, and the object is heated. The steam becomes drain (condensate) by condensing.

  The first drain pipe 14 is connected to the steam using device 13. The drain generated by the condensation of the steam in the steam using device 13 is recovered through the first drain pipe 14. The first drain pipe 14 is provided with a liquid pumping device 15. The liquid pumping device 15 is a pump that pumps the drain generated in the steam using device 13 to the downstream side through the first drain pipe 14. For example, in the liquid pressure feeding device 15, the drain of the steam using device 13 flows in through the first drain pipe 14 and is temporarily stored. When the drain storage amount reaches a predetermined amount, a high-pressure working gas is introduced into the liquid pumping device 15, and the stored drain is pumped to the downstream side of the first drain pipe 14 by the pressure of the working gas. When the drain is pumped, the drain again flows from the steam using device 13 into the liquid pumping device 15 and is stored. In this way, in the liquid pumping device 15, the inflow of drain and the pumping (discharge) of drain are alternately performed.

  The plurality of second drain pipes 16 are connected to the steam pipe 11 and the first drain pipe 14. Specifically, the upstream end of the second drain pipe 16 is connected to the steam pipe 11, and the downstream end of the second drain pipe 16 is connected to the first drain pipe 14. The plurality of second drain pipes 16 are provided at intervals (for example, 20 to 30 m). In the steam pipe 11, a part of the steam may condense and become drainage. The condensed drain is collected in the first drain pipe 14 via the second drain pipe 16.

  A drain trap 17 is provided in the middle of the second drain pipe 16. Drain generated in the steam pipe 11 flows into the drain trap 17 through the second drain pipe 16. Drain mixed with steam flows into the drain trap 17 from the steam pipe 11. The drain trap 17 automatically discharges only the drained water to the downstream side due to the upstream and downstream pressure difference (the difference between the upstream pressure and the downstream pressure). That is, the drain trap 17 prevents the passage of steam from the steam pipe 11 while allowing the drain to pass from the steam pipe 11. The drain generated in the steam pipe 11 joins the drain flowing through the first drain pipe 14 via the second drain pipe 16 and is pumped downstream.

  FIG. 2 is a cross-sectional view of the first drain pipe 14 at the connection portion of the second drain pipe 16. FIG. 3 is a longitudinal sectional view of the first drain pipe 14 at the connection portion of the second drain pipe 16. Here, the transverse sectional view is a sectional view orthogonal to the axis X of the first drain pipe 14. The longitudinal sectional view is a sectional view along the axis X of the first drain pipe 14. Specifically, FIG. 2 is a cross-sectional view taken along line II-II in FIG. 3 is a cross-sectional view taken along line III-III in FIG.

  Of the second drain pipe 16, a downstream end portion 16 a that is an end connected to the first drain pipe 14 is a portion below the axis X of the first drain pipe 14 in the first drain pipe 14. It is connected to the. Specifically, the downstream end portion 16 a is connected to the lowest portion of the first drain pipe 14.

  Further, the downstream end portion 16 a protrudes into the first drain pipe 14. The downstream end 16a extends in a direction inclined with respect to the radial direction centering on the axis X toward the downstream side of the drain flow direction of the first drain pipe 14 (that is, the direction of the axis X). The downstream end of the downstream end portion 16 a is located in a position below the axis X of the first drain pipe 14 in the first drain pipe 14. At the downstream end of the downstream end portion 16a, an outlet 16b through which drain flowing through the second drain pipe 16 flows is formed. That is, the second drain pipe 16 causes the drain to flow to a position below the axis X of the first drain pipe 14 in the first drain pipe 14.

  Furthermore, an inlet 16 c is formed in the downstream end portion 16 a for introducing the drain flowing through the first drain pipe 14 into the second drain pipe 16. A plurality of introduction ports 16c are provided at intervals in the circumferential direction of the downstream end portion 16a.

  In the drain recovery system 1 configured as described above, the pressure of the steam flowing through the steam pipe 11 is higher than atmospheric pressure, while the pressure of the drain flowing through the first drain pipe 14 is substantially atmospheric pressure. For this reason, the drain flowing through the second drain pipe 16 decreases in pressure as it flows toward the first drain pipe 14, and can re-evaporate. The drain flowing out from the second drain pipe 16 to the first drain pipe 14 may be mixed with reevaporated steam (hereinafter also referred to as “flash steam”). And the drain which distribute | circulates the 2nd drain pipe 16 is the drain generate | occur | produced in the steam pipe 11, and is high temperature compared with the drain which distribute | circulates the 1st drain pipe 14. FIG. Similarly, flash steam is hot. When this high-temperature flash vapor flows into the relatively low-temperature drain that flows through the first drain pipe 14, it condenses rapidly, and at that time, an impact and sound may be generated. When a relatively large steam mass (hereinafter also referred to as “steam mass”) is condensed rapidly, a phenomenon in which a large impact and sound are generated, so-called water hammer occurs.

  On the other hand, when the outlet 16b of the second drain pipe 16 is positioned below the axis X of the first drain pipe 14, the occurrence of water hammer can be reduced. Specifically, the flash vapor that has flowed from the second drain pipe 16 into the first drain pipe 14 floats upward in the first drain pipe 14. When flash steam collects in the upper part of the first drain pipe 14, a large steam mass can be formed. However, since the outlet 16b of the second drain pipe 16 is located below the axis X in the first drain pipe 14, a distance from the outlet 16b to the upper portion of the first drain pipe 14 is secured. The As a result, the distance that the flash steam moves from the outlet 16b to the upper portion of the first drain pipe 14 becomes longer, and the flash steam comes into contact with more drain, that is, it comes into contact with the drain for a longer time. Condensation of the flash vapor is promoted before reaching the upper portion of the first drain pipe 14 from the outlet 16b. As a result, it becomes difficult for a large vapor mass to be formed in the upper part of the first drain pipe 14, and as a result, generation of water hammer is reduced.

  In addition, the downstream end portion 16 a extends in a direction inclined toward the downstream side in the drain flow direction of the first drain pipe 14 with respect to the radial direction centering on the axis X. When the flash steam rises right above the outlet 16b, the flash steam reaches the upper part of the first drain pipe 14 in the shortest distance. On the other hand, when the flash vapor rises from the outlet 16b in a direction inclined with respect to the radial direction centering on the axis X, the distance to the upper portion of the first drain pipe 14 becomes longer. In the first place, even if the flash steam flows out from the outlet 16b in the radial direction, the drain flows in the first drain pipe 14, and therefore the drain flow direction of the first drain pipe 14 with respect to the radial direction. The flash steam flows in a direction inclined to the downstream side of the water. In addition, the downstream end portion 16a extends in a direction inclined to the downstream side in the drain flow direction of the first drain pipe 14 with respect to the radial direction, so that the flash vapor is in the first direction with respect to the radial direction. The first drain pipe 14 flows further in a direction inclined further to the downstream side of the drain flow direction, and the distance to the upper portion of the first drain pipe 14 is further increased. As a result, the time for the flash vapor to come into contact with the drain is further secured, and the condensation of the flash vapor is further promoted. Thereby, generation | occurrence | production of a water hammer is reduced more.

  Furthermore, the downstream end portion 16a protrudes into the first drain pipe 14, and the drain that flows through the first drain pipe 14 is introduced into the downstream end portion 16a through the introduction port 16c. The flash vapor of the second drain pipe 16 is mixed with the drain of the first drain pipe 14 in the downstream end portion 16a, that is, before flowing out to the first drain pipe 14, and the condensation is promoted. Thereby, the formation of a large vapor mass in the first drain pipe 14 is further reduced. As a result, the occurrence of water hammer is further reduced.

  Furthermore, since the downstream end portion 16a protrudes into the first drain pipe 14, entry of foreign matter into the outflow port 16b is reduced. In other words, when foreign matter is contained in the drain that flows through the first drain pipe 14, the foreign matter having a large weight can precipitate or stay in the lower portion of the first drain pipe 14. As described above, even if the downstream end portion 16 a is connected to the lower portion of the first drain pipe 14, the downstream end portion 16 a protrudes into the first drain pipe 14, thereby allowing the downstream end portion 16 a to be downstream. The outlet 16b formed at the end is positioned higher than the lowest portion of the first drain pipe 14. As a result, foreign matter that precipitates or stays in the lower portion of the first drain pipe 14 is difficult to enter the outlet 16b.

  As described above, the drain recovery system 1 includes the first drain pipe 14 through which the drain circulates and the second drain pipe 16 through which the drain having a temperature higher than that of the drain through the first drain pipe 14 flows out to the first drain pipe 14. The second drain pipe 16 causes the drain to flow out to a position below the axis X of the first drain pipe 14 in the first drain pipe 14.

  According to this configuration, the distance from when the flash vapor flows from the second drain pipe 16 to the first drain pipe 14 until it reaches the upper portion of the first drain pipe 14 is increased. Since the time for the flash vapor to contact the drain in the first drain pipe 14 is secured, the condensation of the flash vapor is promoted. As a result, the flash vapor disappears before reaching the upper part of the first drain pipe 14, or the size of the flash steam is reduced when the flash steam reaches the upper part of the first drain pipe 14. As a result, it is difficult for a large vapor mass to be formed in the upper portion of the first drain pipe 14, and the occurrence of water hammer is reduced.

  The second drain pipe 16 is connected to a portion of the first drain pipe 14 below the axis X and is connected to the first drain pipe 14 of the second drain pipe 16. The downstream end portion 16 a protrudes inside the first drain pipe 14.

  According to this configuration, foreign matter that precipitates or stays in the lower portion of the first drain pipe 14 does not easily enter the second drain pipe 16.

  Furthermore, an inlet 16 c for introducing the drain flowing through the first drain pipe 14 into the second drain pipe 16 is formed at the downstream end portion 16 a of the second drain pipe 16.

  According to this structure, the drain which distribute | circulates the 1st drain pipe 14 is introduce | transduced into the downstream end part 16a via the inlet 16c. The flash vapor in the second drain pipe 16 is mixed with the drain of the first drain pipe 14 at a stage before flowing out to the first drain pipe 14, and the condensation is promoted. Thereby, it becomes difficult to form a large vapor mass in the upper part of the 1st drain pipe 14, and generation | occurrence | production of a water hammer is further reduced.

  In addition, the second drain pipe 16 is inclined in a direction inclined toward the downstream side of the drain flow direction of the first drain pipe 14 with respect to the direction orthogonal to the axis X when the drain flows out to the first drain pipe 14. Spill.

  According to this configuration, the flash vapor flowing out from the second drain pipe 16 to the first drain pipe 14 does not float directly upward toward the upper portion of the first drain pipe 14, but is drained in the first drain pipe 14. As it flows in the flow direction, it gradually rises to the top of the first drain pipe 14. Since it takes a long time for the flash vapor to come into contact with the drain before reaching the upper portion of the first drain pipe 14, it becomes difficult to form a large vapor mass at the upper portion of the first drain pipe 14. As a result, the occurrence of water hammer is further reduced.

  Furthermore, the drain recovery system 1 further includes a steam pipe 11 through which steam flows, and the second drain pipe 16 causes the drain generated in the steam pipe 11 to flow out to the first drain pipe 14.

  According to this structure, the drain which distribute | circulates the 2nd drain pipe 16 is the drain which generate | occur | produced in the steam pipe 11, and is comparatively high temperature. That is, the relatively high temperature flash vapor from the second drain pipe 16 flows into the relatively low temperature drain of the first drain pipe 14. Therefore, the flash vapor is easily condensed in the first drain pipe 14. In such a configuration, it is particularly effective to drain the drain from the second drain pipe 16 to the position below the axis X in the first drain pipe 14.

<< Other Embodiments >>
As described above, the embodiment has been described as an example of the technique disclosed in the present application. However, the technology in the present disclosure is not limited to this, and can also be applied to an embodiment in which changes, replacements, additions, omissions, and the like are appropriately performed. Moreover, it is also possible to combine each component demonstrated by the said embodiment and it can also be set as a new embodiment. In addition, among the components described in the attached drawings and detailed description, not only the components essential for solving the problem, but also the components not essential for solving the problem in order to illustrate the technology. May also be included. Therefore, it should not be immediately recognized that these non-essential components are essential as those non-essential components are described in the accompanying drawings and detailed description.

  About the said embodiment, it is good also as following structures.

  The drain or flash steam that the second drain pipe 16 flows out to the first drain pipe 14 is not limited to the drain or flash steam generated in the steam pipe 11. For example, the second drain pipe 16 may be configured to cause drain or flash steam generated in the steam heating apparatus to flow out to the first drain pipe 14. That is, the upstream end of the second drain pipe 16 can be connected to any place where drain or flash steam is generated. Since the technique disclosed here is effective in a configuration in which drain having a temperature higher than that of the drain of the first drain pipe 14 flows out through the second drain pipe 16, steam flows through the upstream end of the second drain pipe 16. Or is preferably connected to a place where drainage occurs.

  The downstream end portion 16a of the second drain pipe 16 is connected to the lowest portion of the first drain pipe 14, but is not limited thereto. As long as the outlet 16b of the second drain pipe 16 is positioned below the axis X of the first drain pipe 14, the portion to which the downstream end portion 16a is connected is not limited. For example, even if the downstream end 16a is connected to a portion of the first drain pipe 14 that is above the axis X, the outlet 16b is positioned below the axis X of the first drain pipe 14. It only has to be.

  Further, the downstream end portion 16 a may not protrude into the first drain pipe 14. That is, the outflow port 16 b may be opened flush with the inner peripheral surface of the first drain pipe 14.

  Further, the downstream end portion 16a extends in a direction inclined with respect to the radial direction centered on the axis X, but is not limited thereto. FIG. 4 is a longitudinal sectional view of the first drain pipe 14 at the connection portion of the second drain pipe 216 according to the modification. As shown in FIG. 4, the downstream end 216 a of the second drain pipe 216 may protrude inward in the radial direction with the axis X as the center. According to this configuration, the downstream end 216a allows flush steam to flow out in the radial direction. However, since the drain is circulated in the first drain pipe 14, the flash vapor does not float directly above, but downstream of the radial direction of the drain of the first drain pipe 14 in the drain direction. It flows in the direction of inclination. That is, even if the downstream end 216a extends in the radial direction, the flash vapor does not reach the upper part of the first drain pipe 14 in the shortest distance. On the other hand, since the downstream end 216a extends in a direction orthogonal to the drain flow direction of the first drain pipe 14, the drain flowing through the first drain pipe 14 is introduced into the downstream end 216a from the inlet 216c. It becomes easy to be done. As a result, the condensation of the flash steam by the mixing of the flash steam in the downstream end portion 216a and the drain of the first drain pipe 14 is further promoted.

  FIG. 5 is a longitudinal sectional view of the first drain pipe 14 at the connection portion of the second drain pipe 316 according to another modification. Further, as shown in FIG. 5, the downstream end portion 316 a of the second drain pipe 316 may be bent in the drain flow direction of the first drain pipe 14 after protruding into the first drain pipe 14. According to this configuration, the downstream end portion 316 a causes the flush steam to flow out in the drain flow direction of the first drain pipe 14. Thereby, time until flash vapor reaches the upper part of the 1st drain pipe 14 becomes longer. As a result, the formation of a large vapor mass at the upper part of the first drain pipe 14 is further reduced, and the generation of water hammer is further reduced.

  As described above, the technology disclosed herein is useful for a drain recovery system.

1 Drain recovery system 11 Steam pipe 14 First drain pipes 16, 216, 316 Second drain pipes 16a, 216a, 316a Downstream end portions 16c, 216c, 316c Inlet X axis

Claims (5)

A first drain pipe through which the drain circulates;
In a drain recovery system comprising a second drain pipe for letting drain having a temperature higher than the drain flowing through the first drain pipe to the first drain pipe,
The drain recovery system, wherein the second drain pipe causes drain or re-evaporated vapor of the drain to flow out of the first drain pipe to a position below the axis of the first drain pipe. The drain recovery system according to claim 1,
The second drain pipe is connected to a portion of the first drain pipe below the axis,
A drain recovery system, wherein a downstream end portion, which is an end portion connected to the first drain pipe, of the second drain pipe protrudes into the first drain pipe. The drain recovery system according to claim 2,
A drain recovery system, wherein an inlet for introducing the drain flowing through the first drain pipe into the second drain pipe is formed at the downstream end of the second drain pipe. The drain recovery system according to any one of claims 1 to 3,
The second drain pipe is inclined toward the downstream side in the drain flow direction of the first drain pipe with respect to the direction perpendicular to the axis when drain or re-evaporated vapor flows out to the first drain pipe. The drain recovery system is characterized in that the drain is discharged in the direction or the flow direction of the drain of the first drain pipe. In the drain collection system according to any one of claims 1 to 4,
A steam pipe through which steam flows,
The second drain pipe causes the drain generated in the steam pipe or the re-evaporated steam of the drain to flow out to the first drain pipe.

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