JP5141236B2 - Water supply device for deaerated water - Google Patents

Description

  The present invention relates to a deaerated water supply device that supplies deaerated water to a steam generator such as a steam boiler.

  In the steam generator, if the air is dissolved in the boiler water supplied into the can, the inside of the can is easily corroded by oxygen contained in the air. In some cases, degassing treatment is performed to remove oxygen dissolved in water. The deaerated water subjected to the deaeration process is stored in a water supply tank and supplied from the water supply tank to the steam generator. Further, in order to save fuel consumption of the steam generator, a deaerated water supply device is also known in which the steam after use in a heat exchanger or the like is collected in a water supply tank to raise the water temperature in the water supply tank. .

As a deaeration water supply apparatus employing this type of heat recovery system, a mixing box whose lower end opening is submerged in the water in the water supply tank is attached to the water supply tank. There is an apparatus in which drain from a steam generator is introduced. In this apparatus, the drain is opened in the mixing box, and the flash steam generated there and the circulating water sent from the circulation pump are mixed to recover the heat of the flash steam. Such a heat recovery system using a mixing box can recover flash steam directly and is effective as a heat recovery system (see Patent Document 1).
Japanese Utility Model Publication No. 4-49711

  In the steam recovery system in the deaerated water supply apparatus described in Patent Document 1, when the circulating water circulating through the circulation pump and the flash steam are mixed, if the recovery amount of the flash steam increases, the circulation water increases accordingly. As the amount of water increases, the phenomenon that the mixed water falls below 100 ° C. may occur. When the mixed water becomes less than 100 ° C., the air in the gas phase of the water supply tank is sucked from the vent of the mixing box, and this air is mixed into the deaerated water in the water tank. DO value: oxygen concentration in deaerated water) may increase. In order to eliminate such a phenomenon of air suction, it is conceivable to eliminate the ventilation hole of the mixing box. However, if the ventilation hole is eliminated, tank vibration occurs when the temperature in the water supply tank reaches 100 ° C or higher. However, the water supply tank may be damaged.

  Therefore, in a heat recovery system that directly recovers flash steam using a flash box that mixes circulating water and flash steam, degassing that can solve the problem of re-dissolution risk while recovering most of the flash steam. There is a need for a water supply system. The above is the subject of the present invention.

  The present invention has been made in view of such problems, and in a heat recovery system that directly recovers flash steam using a flash box that performs mixing of circulating water and flash steam, while recovering most of the flash steam. An object of the present invention is to provide a deaerated water supply device capable of solving the problem of oxygen re-dissolution risk.

  The present inventor makes the vapor phase portion of the water supply tank full of steam and purges the air in the gas phase portion with steam, thereby almost eliminating the suction of air into the flash box and reducing the amount of dissolved oxygen in the deaerated water. Based on this finding, the inventors have invented a new deaerated water supply device as described below.

According to the present invention, deaerated water is stored, a water supply tank for supplying the deaerated water to the steam generator, a first vent hole opening in a gas phase part of the water supply tank is formed on a side surface, and a lower end opening is formed. A deaerated water supply device comprising a flush box that is immersed in deaerated water in the water supply tank and that introduces circulating water of the deaerated water in the water supply tank and a drain generated from the steam generator. The steam generated in the steam generator is passed through a drain recovery line through a heat exchanger, a part of the steam is taken out from a branch line branched from the middle of the drain recovery line, and introduced into the flash box, The present invention relates to a water supply device for deaerated water, wherein steam is discharged from the first vent hole to a gas phase portion of the water supply tank.

A portion of the vapor generated in the previous SL steam generator is taken out directly from the vapor generator, it is preferably introduced into the flash box.

A second vent hole is formed to open into the flash box on the side surface, submerged lower end opening is deaerated water of the water supply tank, so that the upper opening is opposite to the inlet portion of the feed water and drain the mixing pipe is provided as a double pipe in the flash box, it is preferable that introduction port for introducing a portion of the steam generated in the steam generator is opposed to a side surface of the mixing pipe.

The present invention also provides a water supply tank for storing deaerated water and supplying the deaerated water to the steam generator, and a lower end opening is submerged in the deaerated water in the water supply tank. A degassing water supply device comprising circulating water of water and a flash box for introducing drain generated from the steam generator, wherein the steam generated in the steam generator is recovered via a heat exchanger. The present invention relates to a water supply device for deaerated water, wherein a part of steam is taken out from a branch line branched from the middle of the drain recovery line and introduced into a gas phase portion of the water supply tank.

A portion of the vapor generated in the previous SL steam generator is taken out directly from the vapor generator, it is preferably introduced into the gas phase portion of the water tank.

  According to the present invention, in a heat recovery system that directly recovers flash steam using a flash box that mixes circulating water and flash steam, the problem of oxygen re-dissolution risk is solved while recovering most of the flash steam. It is possible to provide a water supply device for deaerated water that can be used.

  Hereinafter, embodiments of the present invention will be described. The deaerated water supply device of the present invention includes a water supply tank that stores deaerated water and supplies the deaerated water to a steam generator. The water supply tank is provided with a flash box having a side surface formed with a first vent hole that opens to a gas phase portion of the water supply tank. The lower end opening of this flash box is submerged in the deaerated water in the water supply tank, the circulating water of the deaerated water in the water supply tank and the drain generated from the steam generator are introduced into the upper part, and the flash steam generated from the drain And circulating water are mixed in the mixing chamber at the top of the flash box. A part of the steam generated in the steam generator is introduced into the lower flash chamber in the flash box, and the steam is discharged from the first vent formed in the side wall of the flash chamber to the gas phase portion of the water supply tank. Fill the part with steam. As a result, the air in the gas phase portion is discharged from the exhaust port of the water supply tank by the steam purge, and the air in the gas phase portion is sucked into the flash chamber from the first vent hole to increase the dissolved oxygen in the deaerated water. The risk of making it happen is avoided.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a system configuration diagram of a deaerated water supply device according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view of a drain recovery device in the first embodiment.

  As shown in FIG. 1, a deaerated water supply apparatus according to the present invention includes a water supply tank 2 that supplies deaerated water to a steam generator 1, and a deaerated water inflow pipe 3 that introduces deaerated water into the water supply tank 2. And a drain recovery device 4 attached to the upper part of the water supply tank 2. The deaerated water 5 flowing from the deaerated water inflow pipe 3 is stored in the feed water tank 2, and the deaerated water is supplied to the steam generator 1 through the water supply line 6. An exhaust port 7 is provided in the upper part of the water supply tank 2, and air in the gas phase section 35 in the water supply tank 2 is exhausted from the exhaust port 7 through the exhaust line 8. The exhaust line 8 is provided with a temperature sensor 10 for monitoring the temperature inside the pressure gauge 9 and the gas phase section 35, and a detection signal from the temperature sensor 10 is transmitted to the control panel 11. A temperature sensor 12 for monitoring the temperature of the deaerated water 5 in the water supply tank 2 is provided below the water supply tank 2, and a detection signal from the temperature sensor 12 is also transmitted to the control panel 11.

  As shown in FIGS. 1 and 2, the drain recovery device 4 includes a flash box 14 attached to the upper part of the water supply tank 2, and a lower end opening 14 c of the flash box 14 is immersed in the deaerated water 5. ing. A partition plate 15 is provided in the middle of the flash box 14, and the upper part of the flash box 14 is partitioned into a mixing chamber 14a and the lower part is partitioned into a flash chamber 14b. A mixing pipe 13 is attached as a double pipe at the center of the partition plate 15, the upper end of the mixing pipe 13 opens toward the mixing chamber 14 a, and the lower end is submerged in the deaerated water 5. A first vent hole 19 is formed in the side wall of the flash chamber 14 b, and a second vent hole 29 located below the first vent hole 19 is formed in the side wall of the mixing pipe 13.

  In the mixing chamber 14a of the flash box 14, a circulating water shower pipe 16 is arranged at the upper part, and a drain water shower pipe 17 is arranged at the lower part. The circulating water shower pipe 16 is supplied with the circulating water of the deaerated water from the lower part of the water supply tank 2 through the circulating water line 18. The circulating water line 18 is provided with a circulation pump 20, valves 21 and 22, a flow meter 23, a pressure gauge 24 and the like. The circulation pump 20 is controlled to be turned on / off by the control panel 11. Drain is supplied to the drain water shower pipe 17 through a drain recovery line 26 through which the drain that has passed through the heat exchanger 25 and the steam trap 41 passes from the steam generator 1. The drain recovery line 26 is provided with a valve 27.

  A branch line 28 that branches from between the heat exchanger 25 and the valve 27 is connected to the drain recovery line 26. The tip of the branch line 28 is connected to an inlet (socket) 30 provided in the flash chamber of the flash box 14. The branch line 28 is provided with a valve 31 and pressure gauges 32 and 33.

  Next, the operation will be described. After the steam generated in the steam generator 1 passes through the heat exchanger 25, it is supplied as drain from the drain recovery line 26 to the drain water shower pipe 17, and is ejected from the drain water shower pipe 17 to the mixing chamber 14a as flash steam. .

  The deaerated water 5 flowing from the deaerated water inflow pipe 3 is stored in the water supply tank 2. A granular suspended matter 34 is suspended on the surface of the deaerated water 5. When the circulation pump 20 is turned on by a signal from the control panel 11, the deaerated water is supplied as circulating water from the circulating water line 18 to the circulating water shower pipe 16, ejected from the circulating water shower pipe 16, and mixed with flash steam. Thus, mixed water is generated, and the mixed water falls from the mixing pipe 13 and flows into the deaerated water 5. At this time, the flash steam in the mixed water is discharged from the second vent hole 29 to the flash chamber 14b, and the vibration of the drain recovery device 4 due to the passage of the flash steam is prevented.

  A part of the drain flows from the inlet 30 of the flash box 14 into the flash chamber 14b through the branch line 28 from the drain recovery line 26. The flash vapor filled in the flash chamber 14 b flows into the gas phase portion 35 of the water supply tank 2 from the first vent hole 19, the flash vapor is filled in the gas phase portion 35, and the air that was present in the gas phase portion 35. Is discharged from the exhaust port 7 by steam purge.

  Conventionally, as the recovered amount of drain increases, the amount of circulating water for mixing also increases, so the temperature of the mixed water decreases. When the temperature of the mixed water becomes less than 100 ° C., the vapor phase is higher than that of the flash chamber 14b. The temperature of the part 35 becomes higher, and therefore, a phenomenon occurs in which the gas in the gas phase part 35 is sucked into the flash chamber 14 b from the first vent hole 19. In the present embodiment, the high-temperature flash vapor introduced from the branch line 28 fills the flash chamber 14b and is ejected from the first vent hole 19 to the gas phase portion 35. Inhalation of air is prevented.

  Furthermore, in the present embodiment, the air in the gas phase part 35 is purged by the steam purge, and the gas phase part 35 is filled with the steam, so that the temperature in the mixing pipe 13 becomes less than 100 ° C. Even so, most of the gas sucked into the second vent hole 29 from the first vent hole 19 is vapor, and therefore, air (oxygen) is prevented from flowing into the deaerated water 5 from the flash chamber 14b.

  The temperature of the deaerated water 5 in the water supply tank 2 is constantly monitored by the temperature sensor 12, and the temperature of the exhaust gas from the gas phase section 35 is constantly monitored by the temperature sensor 10. The detection signals of the temperature sensors 10 and 12 are transmitted to the control panel 11, and the circulation pump 20 is on / off controlled by the signal from the control panel 11. The circulating pump 20 is turned on when the temperature sensor 10 is equal to or higher than a set temperature (for example, 100 ° C.) and the temperature sensor 12 is equal to or lower than the set temperature, and when the temperature sensor 10 is equal to or lower than the set temperature or the temperature sensor 12 is equal to or higher than the set temperature. It can be controlled to turn off.

  When the drain is branched from the drain recovery line 26 via the branch line 28, the drain branching ratio can be arbitrarily set by the valves 27 and 31. For example, if the drain recovery line valve 27 is closed, all of the drain in the drain recovery line 26 flows to the branch line 28, and if the valve 31 of the branch line 28 is closed, the flow of drain into the branch line 28 is stopped. The Since the temperature of the flash chamber 14b increases as the amount of drain in the branch line 28 increases, the branching ratio of the drain so that the temperature of the flash chamber 14b becomes 100 ° C. or higher according to the amount of mixed water in the mixing chamber 14a. Can be adjusted. If necessary, the temperature in the flash chamber 14b can be detected, and the valves 27 and 31 can be automatically controlled based on the detection signal.

  FIG. 3 is a system configuration diagram of a deaerated water supply device according to a second embodiment of the present invention. In addition, description of the same members or parts having the same functions as those in FIGS. 1 and 2 in the first embodiment will be omitted.

  In the second embodiment, instead of the branch line 28 in the first embodiment, a steam extraction line 36 for extracting a part of the steam is connected to the steam generator 1, and this steam extraction line 36 is connected to the inlet 30 of the flash chamber 14b. Connected to. The steam extraction line 36 is provided with a steam strap 42, a pressure adjustment valve 37, a valve 38 and a pressure gauge 39.

  In the second embodiment, a part of the steam generated in the steam generator 1 is introduced into the flash chamber 14b via the steam extraction line 36, and the flash chamber 14b is filled with the flash steam as in the first embodiment. The gas is jetted from the first vent hole 19 to the gas phase portion 35. In the second embodiment, even when the drain recovered from the drain recovery line 26 is small, the steam can be directly taken out from the steam generator 1 and filled into the flash chamber 14b.

  FIG. 4 is a system configuration diagram of a deaerated water supply device according to a third embodiment of the present invention, and FIG. 5 is a cross-sectional view of a drain recovery device. In addition, description of the same members or parts having the same functions as those in FIGS. 1 and 2 in the first embodiment will be omitted.

  In the third embodiment, the drain recovery device 4 includes a flash box 14 attached to the water supply tank 2, and a lower end opening 14 c of the flash box 14 is submerged in the deaerated water 5. And the drain collection | recovery apparatus 4 of this embodiment is comprised only with the flash box 14, without providing the mixing pipe 13 as a double pipe in 1st, 2nd embodiment. The first vent hole 19 is formed in the side wall of the flash box 14, the circulating water shower pipe 16 is arranged at the upper part of the flash box 14, and the drain water shower pipe 17 is arranged at the lower part thereof as in the first embodiment. It is the same.

  In the present embodiment, the drain from the branch line 28 is directly introduced into the gas phase portion 35 of the feed water tank 2 from the inlet 40, the vapor phase portion 35 is filled with steam, and at the same time, the gas phase portion 35 is purged by steam purge. The inside air is discharged from the exhaust port 7. Also in this embodiment, even if the temperature in the flash box 14 becomes less than 100 ° C., most of the gas sucked from the first vent hole 19 is vapor, and therefore air (oxygen) is drawn from the flash chamber 14b. Inflow into the deaerated water 5 is prevented.

  FIG. 6 is a system configuration diagram of a deaerated water supply device according to a fourth embodiment of the present invention. In addition, description of the same members or parts having the same functions as those in FIGS. 1 and 2 in the first embodiment will be omitted.

  In 4th Embodiment, it replaces with the branch line in 3rd Embodiment, the steam extraction line 36 which takes out a part of vapor | steam is connected to the steam generator 1, and the inlet provided in the gaseous-phase part 35 of the feed water tank 2 40 is connected. In the fourth embodiment, a part of the steam generated in the steam generator 1 is introduced into the gas phase part 35 via the steam strap 42, and the gas phase part 35 is filled with the steam as in the third embodiment. In the fourth embodiment, even when the drain recovered from the drain recovery line 26 is small, it is possible to take out the steam directly from the steam generator 1 and fill the gas phase part 35.

  As described above, according to the embodiment of the present invention, a part of the steam generated in the steam generator is introduced into the flash box, and the steam is supplied from the first vent hole of the flash box to the gas phase portion of the water supply tank. By releasing the air, the phenomenon of air suction from the first vent hole is eliminated. Even if the temperature in the mixing pipe is less than 100 ° C., most of the gas sucked from the first vent hole to the second vent hole is vapor, and therefore air (oxygen) is degassed from the flash chamber. It is prevented from flowing into the water, and an increase in the amount of dissolved oxygen in the deaerated water can be prevented.

  Further, according to the embodiment of the present invention, the steam generated in the steam generator is passed through the drain recovery line via the heat exchanger, and a part of the steam is taken out from the branch line branched from the middle of the drain recovery line. By introducing it into the flash box, part of the drain that passes through the drain recovery line can be used effectively.

  Further, according to the embodiment of the present invention, when a part of the steam generated in the steam generator is directly taken out from the steam generator and introduced into the flash box, the amount of drain passing through the drain recovery line is small. But enough steam can be introduced into the flash box.

  Further, according to the embodiment of the present invention, a mixing pipe as a double pipe is provided in the flash box, and the introduction port for introducing a part of the steam generated in the steam generating device faces the side surface of the mixing pipe. Therefore, even when the steam introduced from the introduction port is ejected toward the flash chamber, the steam can be received by the mixing pipe and the vibration of the flash box can be prevented.

  Further, according to the embodiment of the present invention, by introducing a part of the steam generated in the steam generator into the gas phase part of the water supply tank, the gas phase part is filled with steam, and at the same time, the air in the gas phase part is Since it is exhausted from the exhaust port and no longer sucks air from the first vent hole of the flash box, and the gas phase part is filled with steam, even if the temperature inside the flash box becomes less than 100 ° C, Most of the gas sucked from the first vent hole is steam, so that air (oxygen) is prevented from flowing into the deaerated water from the flash chamber.

  Further, according to the embodiment of the present invention, by removing a part of the steam from the branch line branched from the middle of the drain recovery line and introducing it into the gas phase part of the feed water tank, the drain of the drain passing through the drain recovery line can be obtained. Some can be used effectively.

  Further, according to the embodiment of the present invention, a part of the steam generated in the steam generator is directly taken out from the steam generator and introduced into the gas phase portion, so that the amount of drain passing through the drain recovery line is small. Even in this case, sufficient vapor can be introduced into the gas phase.

  As mentioned above, although embodiment of this invention was described, only the specific example was illustrated, it does not specifically limit this invention, a water supply tank, a drain collection device, a circulating water line, a drain collection line, a steam generator, etc. The specific configuration can be changed as appropriate. The effects described in the embodiments of the present invention are only the most preferable effects resulting from the present invention, and the effects of the present invention are limited to those described in the embodiments of the present invention. is not.

1 is a system configuration diagram of a deaerated water supply device according to a first embodiment of the present invention. It is sectional drawing of the drain collection | recovery apparatus of the water supply apparatus for deaerated water of 1st Embodiment of this invention. It is a system block diagram of the water supply apparatus for deaerated water of 2nd Embodiment of this invention. It is a system block diagram of the water supply apparatus for deaerated water of 3rd Embodiment of this invention. It is sectional drawing of the drain collection | recovery apparatus of the water supply apparatus for deaerated water of 3rd Embodiment of this invention. It is a system block diagram of the water supply apparatus for deaerated water of 4th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Steam generator 2 Water supply tank 4 Drain collection | recovery apparatus 3 Deaerated water inflow pipe 7 Exhaust port 13 Mixing pipe 14 Flash box 14a Mixing chamber 14b Flash chamber 16 Circulating water shower pipe 17 Drain water shower pipe 19 1st ventilation hole 25 Heat exchanger 26 Drain recovery line 28 Branch line 29 Second vent hole 35 Gas phase portion 36 Steam extraction line

Claims (5)

A water supply tank that stores deaerated water and supplies the degassed water to the steam generator, a first vent hole that opens to a gas phase part of the water supply tank is formed on a side surface, and a lower end opening is formed in the water supply tank. A water supply device for deaerated water, comprising a flush box for introducing drained water generated from the circulating water of the deaerated water in the water supply tank and the steam generator,
The steam generated in the steam generator is passed through a drain recovery line through a heat exchanger, a part of the steam is taken out from a branch line branched from the middle of the drain recovery line , introduced into the flash box, A water supply device for deaerated water, wherein steam is discharged from the first vent hole to a gas phase portion of the water supply tank.   The deaerated water supply device according to claim 1, wherein a part of the steam generated in the steam generator is directly taken out from the steam generator and introduced into the flash box.   A second ventilation hole that opens into the flash box is formed on a side surface, a lower end opening is submerged in the deaerated water in the water supply tank, and an upper end opening is opposed to the circulating water and drain introduction portion. The mixing pipe as a double pipe is provided in the flash box, and an introduction port for introducing a part of the steam generated in the steam generating device faces a side surface of the mixing pipe. The water supply device for deaerated water according to 1. A dewatered water is stored, a water supply tank for supplying the degassed water to the steam generator, a lower end opening is submerged in the deaerated water in the water supply tank, and the deaerated water circulating water in the water supply tank and A deaerated water supply device comprising a flash box for introducing drain generated from the steam generator,
The steam generated in the steam generator is passed through a drain recovery line through a heat exchanger, and a part of the steam is taken out from a branch line branched from the middle of the drain recovery line to be in a gas phase part of the water supply tank. A water supply device for deaerated water that is introduced. 5. The deaerated water supply device according to claim 4 , wherein a part of the steam generated in the steam generation device is directly taken out from the steam generation device and introduced into a gas phase portion of the water supply tank.

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