Condensed water discharge system

Abstract

To provide a condensed water discharge system capable of reliably discharging condensed water.SOLUTION: Cold air 91 applied to air heater equipment 10 exchanges heat with steam in heating pipes 11K, 12K, 13K of units 11, 12, 13 to be sent out as warm air 92. Drainage (condensed water) generated by steam being condensed by heat exchange flows out to each discharge pipe 51, 52, 53 and is consolidated in a communication pipe 54 and is discharged to a terminal discharge pipe 55 through a steam trap 15 provided at the communication pipe 54. The terminal discharge pipe 55 is connected to a heat transfer box 2 attached to the discharge pipes 51, 52, 53, and the discharged drainage of 100°C or lower passes through an inside of the heat transfer box 2. The discharge pipes 51, 52, 53 are arranged so as to pass through the heat transfer box 2, and thereby, heat exchange with the drainage passing therethrough is performed.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The condensate drain system of the present application relates to a technology for a condensate drain system having multiple drain paths that each independently discharge steam condensate, and in which these multiple drain paths are collectively connected to a single collective path equipped with an automatic valve. [Background technology]

[0002] An example of a condensate drain system is a drain discharge mechanism for a steam heating facility disclosed in Patent Document 1. This steam heating facility includes multiple steam heating facilities A and B, each of which is supplied with steam and heat-treats an object.

[0003] The steam supplied to steam heating equipment A and B condenses as heat is released during the heating process, producing drainage (condensed water), but if this drainage remains inside steam heating equipment A and B it will interfere with the heating operation, so it must be discharged to the outside as appropriate. For this reason, drainage discharge pipes a and b are installed hanging down from steam heating equipment A and B, so that the generated drainage flows out into drainage discharge pipes a and b, respectively.

[0004] Typically, a condensate discharge pipe is equipped with a steam trap that automatically opens and closes depending on the amount of condensate. That is, when condensate flows into the valve chamber of the steam trap through the condensate discharge pipe, a float in the valve chamber rises depending on the amount of condensate accumulated in the valve chamber, opening the valve port and automatically discharging the condensate based on the pressure in the pipe. After the condensate is discharged, the float descends, closing the valve port and preventing steam leakage. To simplify the installation of such steam traps and reduce costs, a known configuration (group trapping) is used in which multiple condensate discharge pipes are connected to a single discharge pipe, and a single steam trap is installed on this discharge pipe to share the condensate discharge. The steam heating equipment disclosed in Patent Document 1, listed below, also uses group trapping, connecting the lower ends of condensate discharge pipes a and b to a connecting pipe g, and installing a single steam trap 1 on condensate discharge pipe b. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Unexamined Patent Publication No. 4-316791 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the condensate discharge mechanism disclosed in the aforementioned Patent Document 1 has the problem that steam locking occurs in the steam trap (steam trap) 1, making it impossible to discharge condensate. This steam locking refers to a phenomenon in which steam enters and fills the valve chamber of the steam trap, blocking the inflow of condensate, and the float in the valve chamber remains blocking the valve orifice, preventing it from floating up, preventing the condensate from being properly discharged.

[0007] In other words, because steam heating equipment A and B heat the objects separately, the load conditions of the equipment are different, and equipment that releases more latent heat from the steam generates a lot of condensate, while equipment that releases less latent heat generates less condensate. For this reason, equipment that generates an extremely small amount of condensate may simply discharge steam into the condensate discharge pipe instead of condensate. In such cases, a large amount of steam will suddenly enter the valve chest of steam trap 1, filling it.

[0008] As a result, the condensate flowing out from other equipment cannot flow into the steam trap 1 due to the steam filling the valve chest, causing steam locking and preventing the condensate from being discharged properly.

[0009] The condensed water drainage system according to the present invention aims to solve these problems and has an object to provide a condensed water drainage system that can reliably drain condensed water. [Means for solving the problem]

[0010] The condensate drainage system according to the present application comprises: a plurality of individual exhaust paths through which steam flowing from the primary side to the secondary side or condensed water of the steam passes independently; a collective path that collectively connects the secondary sides of the plurality of individual discharge paths and allows the steam or the condensed water to join and pass through; an automatic valve connected to the collecting path, through which the condensed water flows and passes, the automatic valve automatically opening or closing according to the amount of the condensed water that flows in; a terminal discharge path connected to the automatic valve and allowing the condensed water discharged from the automatic valve when the valve is opened to pass from the primary side to the secondary side; It is equipped with The terminal discharge path is in contact with each of the plurality of individual discharge paths. It is characterized by: [Effects of the Invention]

[0011] In the condensed water drainage system according to the present application, the terminal drain path, through which the condensed water passes from the primary side to the secondary side, is in contact with a plurality of individual drain paths, through which steam or condensed water of the steam passes independently. Here, since the saturated temperature of the condensed water is lower than the saturated temperature of the steam, when high-temperature steam flows into one or more individual drain paths, the terminal drain path through which the condensed water passes comes in contact with the individual drain paths, and heat exchange occurs between the terminal drain path and the individual drain paths, thereby keeping the temperature of the steam low.

[0012] This promotes condensation of the steam flowing through the individual discharge path, turning the steam into condensed water that flows into the automatic valve. This prevents steam locking, which occurs when the automatic valve is filled with steam, and ensures that condensed water can be discharged reliably. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic diagram showing the overall configuration of an air heater facility 10 illustrating a first embodiment of a condensed water drainage system according to the present application. DETAILED DESCRIPTION OF THE INVENTION

[0014] [Terminology used in the embodiments] The main terms shown in the embodiments correspond to the following elements of the condensate drainage system according to the present application.

[0015] Heat transfer box 2 and terminal exhaust pipes 55, 56... Terminal exhaust path Steam trap 15...automatic valve First discharge pipe 51, second discharge pipe 52, and third discharge pipe 53... Individual discharge paths Connecting pipe 54... Collecting route

[0016] [First embodiment] A first embodiment of the condensed water drainage system according to the present invention will be described using an air heater facility as an example. Fig. 1 is a schematic diagram showing the overall configuration of an air heater facility 10 in this embodiment.

[0017] (Explanation of the overall configuration of the air heater equipment 10) The air heater equipment 10 is configured to include a first unit 11, a second unit 12, and a third unit 13. The first unit 11, the second unit 12, and the third unit 13 incorporate heating pipes 11K, 12K, and 13K, respectively. The upper sides of the heating pipes 11K, 12K, and 13K are connected to a steam supply pipe 50, and steam is supplied to the first unit 11, the second unit 12, and the third unit 13 through the steam supply pipe 50. The heating pipes 11K, 12K, and 13K are configured as fin tubes, which are metal tubes with fins attached to increase the heat transfer area in order to improve heat exchange efficiency.

[0018] Furthermore, a first exhaust pipe 51, a second exhaust pipe 52, and a third exhaust pipe 53 are connected to the lower sides of the heating pipes 11K, 12K, and 13K, respectively, and drain (condensed water) generated by condensation of steam flows down through these exhaust pipes. Furthermore, the first exhaust pipe 51, the second exhaust pipe 52, and the third exhaust pipe 53 are equipped with heat radiation pipes 51K, 52K, and 53K, respectively. The heat radiation pipes 51K, 52K, and 53K are also made up of fin tubes to improve heat exchange efficiency.

[0019] The first discharge pipe 51, the second discharge pipe 52, and the third discharge pipe 53 are further connected to a communicating pipe 54. Drains flowing down from the first discharge pipe 51, the second discharge pipe 52, and the third discharge pipe 53 flow into this communicating pipe 54 and are collected in the communicating pipe 54.

[0020] A steam trap 15 is provided further downstream of the communicating pipe 54. In this embodiment, a free float type steam trap 15 is used, and the steam trap opens and closes depending on the amount of drain that flows in through the communicating pipe 54.

[0021] That is, the steam trap is formed with an inlet (inflow portion) to which the communicating pipe 54 is connected, and condensate flows from here into the valve chamber (valve chamber portion), which is the internal space. A float (floating means) is provided in the valve chamber so that it can float freely, and moves up and down depending on the amount of condensate accumulated in the valve chamber, automatically opening and closing the orifice (valve port).

[0022] When the float opens the orifice, the high pressure in the piping system is received and the condensate in the valve chamber is automatically drained from the outlet (outlet part) of the steam trap that is connected to the orifice. After draining, the float descends under its own weight and closes the orifice. The outlet of the steam trap is connected to the terminal discharge pipe 55 shown in Figure 1, through which the drained condensate flows out.

[0023] A heat transfer box 2 is attached to the first exhaust pipe 51, the second exhaust pipe 52, and the third exhaust pipe 53, covering each of the heat radiation pipes 51K, 52K, and 53K. The inside of the heat transfer box 2 is a space, and the first exhaust pipe 51, the second exhaust pipe 52, and the third exhaust pipe 53, including the heat radiation pipes 51K, 52K, and 53K, pass through the internal space. Gaskets are provided at the penetration points of the first exhaust pipe 51, the second exhaust pipe 52, and the third exhaust pipe 53, ensuring airtightness of the internal space of the heat transfer box 2.

[0024] A terminal discharge pipe 55 is connected to one end (the side closer to the third discharge pipe 53) of the heat transfer box 2, and the condensate discharged from the steam trap flows into the internal space of the heat transfer box 2. In addition, a terminal discharge pipe 56 is connected to the other end (the side closer to the first discharge pipe 51) of the heat transfer box 2, and the condensate that has flowed into the internal space of the heat transfer box 2 flows out toward the terminal discharge pipe 56.

[0025] In the air heater equipment 10, the steam supply pipe 50 side is the primary side, and the terminal discharge pipe 56 side is the secondary side. The condensate that flows into the internal space of the heat transfer box 2 is subjected to high pressure in the piping system and passes with force from the terminal discharge pipe 55 on the primary side to the terminal discharge pipe 56 on the secondary side. The condensate that flows out of the heat transfer box 2 is transferred from the feedwater tank 41 to the boiler 42 via the terminal discharge pipe 56.

[0026] (Description of the operation of the air heater equipment 10) Next, we will explain the operation of the air heater equipment 10. As described above, steam is supplied to the heating pipes 11K, 12K, and 13K built into the first unit 11, second unit 12, and third unit 13 through the steam supply pipe 50. In this embodiment, steam with a gauge pressure of 0.5 MPaG is used, and this steam has a high saturation temperature of approximately 159°C.

[0027] Cold air 91 is supplied to the air heater equipment 10 from the outside, and as this cold air 91 passes around the first unit 11, the second unit 12, and the third unit 13, heat exchange occurs between the cold air 91 and the steam in the heating pipes 11K, 12K, and 13K, and the cold air 91 is sent out from the air heater equipment 10 as warm air 92.

[0028] The steam loses latent heat through this heat exchange and condenses to generate drainage. The drainage generated in the heating pipes 11K, 12K, and 13K flows out into the communicating pipe 54 through the first discharge pipe 51, the second discharge pipe 52, and the third discharge pipe 53, respectively.

[0029] The condensate that has flowed out into the communicating pipe 54 then flows to the secondary side and into the steam trap 15. The inflow of condensate causes the float inside the steam trap 15 to rise, opening the orifice. With the orifice open, the condensate is automatically discharged from the steam trap 15 due to the force of the high pressure inside the piping. As the condensate is discharged, the float inside the steam trap 15 descends and returns to its seat, blocking the orifice.

[0030] As described above, drain of 100°C or less that is generated in the piping due to the heating operation is automatically discharged as needed by the steam trap 15. This prevents drain from accumulating in the heating pipes 11K, 12K, and 13K, allowing the air heater equipment 10 to perform an appropriate heating operation.

[0031] Here, the air to be heated passes through the first unit 11, the second unit 12 and the third unit 13 in sequence as cold air 91, so the load conditions of each unit are different, with the first unit 11, which is located the most upstream, performing approximately 60% of the total heating, and the degree of heating gradually decreasing in the second unit 12 and the third unit 13.

[0032] As described above, the amount of drainage generated in each unit differs because there is a difference in the degree of heat dissipation of steam due to heat exchange (heat exchange efficiency) between the first unit 11, the second unit 12, and the third unit 13. That is, a large amount of drainage flows out into the first discharge pipe 51 connected to the first unit 11 (heat dissipation pipe 11K) which has the highest degree of heat dissipation (highest heat exchange efficiency), and in the second unit 12 and the third unit 13, the degree of heat dissipation of steam decreases stepwise (heat exchange efficiency decreases), so the amount of drainage flowing out into the second discharge pipe 52 and the third discharge pipe 53 gradually decreases.

[0033] The third unit 13 (heat radiation pipe 13K), which is located furthest downstream, has the lowest degree of heat radiation (lowest heat exchange efficiency) and generates almost no condensate, so steam may flow directly into the third discharge pipe 53. If the steam from the third discharge pipe 53 flows directly into the steam trap 15, steam locking occurs and condensate will no longer be discharged from the steam trap 15. As a result, condensate will gradually accumulate in the heating pipes 11K, 12K, and 13K of each unit, and the heating efficiency of the air heater equipment 10 will decrease significantly.

[0034] However, in this embodiment, the heat transfer box 2 is attached to the first discharge pipe 51, the second discharge pipe 52, and the third discharge pipe 53. As described above, the drain discharged from the steam trap 15 passes through the internal space of the heat transfer box 2 from the terminal discharge pipe 55 toward the terminal discharge pipe 56.

[0035] Therefore, the steam or drain in the first exhaust pipe 51, the second exhaust pipe 52, and the third exhaust pipe 53 exchanges heat with the drain at 100°C or less passing through the heat transfer box 2. At this time, the heat radiation pipes 51K, 52K, and 53K of the first exhaust pipe 51, the second exhaust pipe 52, and the third exhaust pipe 53, respectively, are made up of fin tubes as described above, and therefore, efficient heat exchange can be achieved.

[0036] This heat exchange equalizes the temperature of the steam or condensate in the first discharge pipe 51, the second discharge pipe 52, and the third discharge pipe 53. For example, when steam at approximately 159°C flows inside the third discharge pipe 53, the temperature of the steam in the third discharge pipe 53 drops due to heat exchange with condensate at 100°C or less passing through the heat transfer box 2, promoting condensation of the steam. As a result, part or all of the steam flowing through the third discharge pipe 53 (heat radiation pipe 53K) of the third unit 13 turns into condensate and flows into the steam trap 15, thereby preventing the occurrence of steam locking.

[0037] As described above, in this embodiment, by taking advantage of the fact that the drain is at a lower temperature than the steam, the temperature of the steam is lowered using the path through which the drain passes, thereby promoting condensation, thereby avoiding the occurrence of steam locking with a simple configuration.

[0038] The drain that flows out of the heat transfer box 2 is transported and reused through the terminal discharge pipe 56. That is, the downstream side of the terminal discharge pipe 56 is connected to the water supply tank 41, and the drain is temporarily stored in the water supply tank 41. It is then transported to the boiler 42 and heated, and steam is generated again and transported to a specified steam-using device. By reusing the drain at about 100°C and heating it in the boiler 42, steam can be generated efficiently.

[0039] As described above, drainage water of 100°C or less that flows into the internal space of the heat transfer box 2 passes from the terminal exhaust pipe 55 on the primary side toward the terminal exhaust pipe 56 on the secondary side. The third exhaust pipe 53 (heat radiation pipe 53K) is arranged near the connection point of the terminal exhaust pipe 55 located on the primary side, and since this third exhaust pipe 53 is connected to the heating pipe 13K, which has the lowest degree of heat radiation (heat exchange efficiency), high-temperature steam often flows through it. Furthermore, the first exhaust pipe 51 (heat radiation pipe 51K) is arranged near the connection point of the terminal exhaust pipe 56 located on the secondary side, and since this first exhaust pipe 51 is connected to the heating pipe 11K, which has the highest degree of heat radiation (heat exchange efficiency), drainage often flows through it.

[0040] As described above, in this embodiment, the terminal exhaust pipe 55, the heat transfer box 2, and the terminal exhaust pipe 56 that constitute the terminal exhaust path are arranged in contact with each other from the primary side to the secondary side in the order from the third exhaust pipe 53 (heat radiation pipe 53K), which has a low degree of heat radiation from the steam, to the first exhaust pipe 51 (heat radiation pipe 51K), which has a high degree of heat radiation. Drain of 100°C or less passes through the terminal exhaust pipe 55, the heat transfer box 2, and the terminal exhaust pipe 56 from the primary side to the secondary side. Therefore, the drain exchanges heat in the order from the exhaust pipe through which high-temperature steam is most likely to flow, thereby more effectively lowering the temperature of the steam in the exhaust pipe and promoting condensation of the steam.

[0041] [Other embodiments] In the above-described embodiment, examples are given for each of the individual discharge paths, the collective path, the automatic valve, and the terminal discharge path of the condensate discharge system according to the present application, but these are merely examples, and different configurations can also be adopted for each.

[0042] For example, in the above-described embodiment, an air heater equipment 10 having three discharge pipes, a first discharge pipe 51, a second discharge pipe 52, and a third discharge pipe 53, was exemplified, but the condensate discharge system of the present application may also be applied to an air heater equipment having two or four or more discharge pipes (individual discharge paths).

[0043] Furthermore, in the above-described embodiment, the air heater equipment 10 is given as an example, but the condensate drainage system according to the present application can be applied to systems other than air heater equipment, as long as it is a condensate drainage system in which multiple individual drainage paths are connected in a consolidated path and condensate is discharged through an automatic valve provided in the consolidated path.

[0044] Furthermore, in the above-described embodiment, an example is shown in which the heat transfer box 2, through which the drain discharged from the automatic valve (such as the steam trap 15) passes, is penetrated by a plurality of individual discharge paths (such as the first discharge pipe 51, the second discharge pipe 52, and the third discharge pipe 53), so that the terminal discharge paths (such as the heat transfer box 2 and the terminal discharge pipes 55, 56) are in contact with each of the plurality of individual discharge paths (such as the first discharge pipe 51, the second discharge pipe 52, and the third discharge pipe 53), but other configurations can also be adopted.

[0045] For example, the terminal discharge path may be arranged to intersect with a plurality of individual discharge paths so that the pipes are in direct contact with each other. Alternatively, a highly conductive medium may be interposed between the intersecting pipes.

[0046] Furthermore, in the above-described embodiment, a free float type steam trap 15 is used as an example of an automatic valve, but automatic valves of other structures can be used as long as they open and close automatically according to the amount of drain that flows in. For example, a lever float type steam trap, an inverted bucket type steam trap, or the like may be used as the automatic valve. [Explanation of symbols]

[0047] 2: Heat transfer box 15: Steam trap 51: First discharge pipe 52: Second discharge pipe 53: Third discharge pipe 54: Communication pipe 55, 56: Terminal discharge pipe

Claims

1. a plurality of individual exhaust paths through which steam flowing from the primary side to the secondary side or condensed water of the steam passes independently; a collective path that collectively connects the secondary sides of the plurality of individual discharge paths and allows the steam or the condensed water to join and pass through; an automatic valve connected to the collecting path, through which the condensed water flows and passes, the automatic valve automatically opening or closing according to the amount of the condensed water that flows in; a terminal discharge path connected to the automatic valve and allowing the condensed water discharged from the automatic valve when the valve is opened to pass from the primary side to the secondary side; It is equipped with The terminal discharge path is in contact with each of the plurality of individual discharge paths. A condensate drainage system comprising:

2. 2. The condensate drain system according to claim 1, There is a difference in the degree of heat release due to heat exchange between the steam flowing through the plurality of individual exhaust paths, The terminal exhaust paths are arranged in a manner to contact each other from the primary side to the secondary side in the order of the individual exhaust paths having a low degree of heat dissipation of the steam flowing through the plurality of individual exhaust paths to the individual exhaust paths having a high degree of heat dissipation of the steam flowing through the plurality of individual exhaust paths. A condensate drainage system comprising:

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