JP2006283988A - Deaerating system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely perform deaerating treatment of feed water prepared by mixing make-up water and condensate, and to achieve power saving in deaerating treatment. <P>SOLUTION: This deaerating system 1 for supplying the deaerated feed water to a boiler 8, comprises a first deaerating portion 2 for deaerating the make-up water, a make-up water storing portion 3 for storing the deaerated make-up water, and a second deaerating portion 4 for deaerating the condensate of steam generated in the boiler 8. The condensate deaerated in the second deaerating portion 4 is supplied to the make-up water storing portion 3, and the feed water prepared by mixing the make-up water and the condensate is supplied to the boiler 8. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a deaeration system that degass water supplied to a boiler and suppresses corrosion of a boiler, a steam pipe, and a condensate pipe in a boiler apparatus that collects condensate.

  Boiler devices are used as heat sources in factory facilities of various industries, and supply steam to load equipment on a production line. The steam supplied to the load equipment may be directly used for production of a product or indirectly by a method such as heat exchange. When steam is indirectly used, it is generally performed to collect steam condensate used in the load equipment as condensate and supply water mixed with new makeup water to the boiler.

  In the boiler device, steam is recirculated to the boiler as condensate, so that the amount of makeup water supplied to the boiler can be reduced. Further, since the feed water is heated by the heat of condensate, the amount of heat for generating steam is small, and the fuel consumed by the boiler can be saved. Therefore, the boiler apparatus that collects condensate can be operated economically.

  By the way, a water pipe and a header constituting the boiler body, a steam pipe for supplying steam to the load equipment, or a condensate pipe for collecting condensate from the load equipment is usually a non-passivated metal, for example, Carbon steel and cast iron are used. These non-passivated metals are susceptible to corrosion due to the effects of dissolved oxygen and dissolved carbon dioxide in water.

  When water supply containing dissolved oxygen is supplied to the boiler, a hole shape from the contact surface side of the water pipe or header and boiler water (that is, water supply stored in the can) toward the opposite side in the thickness direction Corrosion, that is, pitting corrosion that occurs in the thickness direction of water pipes and headers. Moreover, when dissolved oxygen in boiler water is heated in the can and taken out together with steam, condensed water containing dissolved oxygen is generated by dissolving in condensed water. And, in the lower part of the steam pipe or the condensate pipe that has been subjected to horizontal drawing, hole corrosion from the contact surface side of these pipes and the condensate toward the opposite side in the thickness direction, that is, the thickness of the pipe Causes pitting corrosion that occurs in the direction.

  On the other hand, when feed water containing carbonate or bicarbonate is supplied to the boiler, these carbonates are thermally decomposed in the can to generate carbon dioxide gas. When the carbon dioxide gas is taken out together with the steam, it is dissolved in the condensed water to generate acidic condensate, which corrodes the steam pipe and the inner surface of the condensate pipe that are in contact with the condensate. Therefore, in order to maintain economical operation of the boiler device, it is important to prevent damage to the boiler, the steam pipe, the condensate pipe, and the like due to corrosion.

  Now, in order to reduce the dissolved oxygen in feed water, for example, a membrane type deaerator is used. This membrane-type deaerator usually uses a hollow fiber-like polymer membrane, and is used when the feed water is hot or contains a lot of suspended solids due to thermal degradation or clogging problems of this polymer membrane. I can't. In other words, the boiler apparatus that collects the condensate can be applied only to the deaeration process at normal temperature and clean makeup water. For this reason, when the recovered condensate contains high-concentration dissolved oxygen, for example, when atmospheric oxygen that has entered the condensate piping when the boiler device is stopped is dissolved in the condensate. The dissolved oxygen concentration of the feed water mixed with the condensate and the makeup water becomes high, and the corrosion of the boiler, the steam pipe, the condensate pipe and the like cannot be sufficiently suppressed.

In addition, in order to reduce dissolved oxygen in the feed water, water is sprayed into the treatment tank through the nozzle,
There is also an example in which a vacuum type deaeration device that performs a deaeration process by reducing the pressure inside the treatment tank is used (Patent Document 1). Furthermore, a nitrogen substitution type deaerator (“deoxygenation and decarboxylation”) is performed by spraying water into the treatment tank through a nozzle and bringing water droplets and nitrogen gas into contact with each other. There is also an example in which a nitrogen substitution type deoxygenation device is also used (Patent Document 2). The vacuum degassing device and the nitrogen-substituting degassing device can avoid the problems of thermal deterioration and blockage even when the water supply is hot or contains a lot of suspended solids, and has a wide range of properties for water supply that can be handled. For this reason, even when the feed water which mixed condensate and makeup water is high temperature and contains the eluate from the said steam piping, the said condensate piping, etc., it can apply to the deaeration process of this feed water.

  However, the vacuum degassing device and the nitrogen substitution degassing device are normally operated so as to maintain the maximum throughput regardless of the required amount of water supply in the boiler. For example, when the required amount of water supply is small, simply reducing the processing amount results in an increase in the amount of water droplets sprayed from the nozzle. In this case, since the total surface area of the water droplets in the treatment tank is reduced, the contact rate between the liquid phase part and the gas phase part is lowered, and the deaeration ability is greatly lowered. As a result, the dissolved oxygen concentration or dissolved carbon dioxide concentration of the feed water cannot be reduced to a desired value.

  Therefore, the vacuum degassing device and the nitrogen substitution degassing device always drive a pressure pump for supplying water into the treatment tank and a water supply pump for taking out water from the treatment tank at a constant rotation speed. The amount of water supplied to the treatment tank and the amount of water supplied from the treatment tank are operated so as to coincide with the maximum treatment amount. And when there is little request | requirement amount of the water supply in the said boiler, the excess water supply which deducted the request | requirement amount from the maximum processing amount is made to recirculate | reflux to the tank provided in the upstream of the said processing tank (patent document 3). Therefore, the conventional vacuum degassing apparatus and the nitrogen substitution degassing apparatus consume a large amount of power due to excessive operation for maintaining the degassing capacity, and easily increase running costs.

JP-A-8-108005 JP 2000-176436 A JP 2003-300062 A

  In this application, “degassing” is not only for removing dissolved gas in water, but also for replacing dissolved gas in water with other gases, for example, dissolved oxygen or dissolved carbon dioxide gas in water such as nitrogen gas. It is also used as a term including the case of replacing with an inert gas.

  The problem to be solved by the present invention is to reliably perform a deaeration process of feed water in which makeup water and condensate are mixed, and to realize power saving related to the deaeration process.

  This invention was made in order to solve the said subject, and the invention of Claim 1 is a deaeration system which supplies the deaerated water supply to a boiler, Comprising: A deaeration process is performed on makeup water A second deaeration unit that degass the steam condensate generated in the boiler, the first deaeration unit; a makeup water storage unit that stores the degassed makeup water; The condensate deaerated in the deaeration unit is supplied to the makeup water storage unit, and the feed water in which makeup water and condensate are mixed is supplied to the boiler.

According to the first aspect of the present invention, the makeup water is degassed in the first degassing processing section, and the degassed makeup water is stored in the makeup water storage section. On the other hand, the condensate is directly introduced into the second deaeration processing unit, deaerated in the second deaeration processing unit, and then supplied to the makeup water storage unit. In the makeup water storage section, the degassed makeup water and the degassed condensate are mixed and secured as feed water, and this feed water is supplied to the boiler.

  Furthermore, the invention described in claim 2 is a deaeration system for supplying deaerated water to the boiler, a first deaeration unit for degassing the make-up water, and a deaeration make-up water A replenishment water storage section for storing the steam, a condensate storage section for storing the condensate of steam generated in the boiler, and a second deaeration section for degassing the condensate in the condensate storage section, The condensate deaerated in the second deaeration unit is supplied to the makeup water storage unit, and the feed water in which makeup water and condensate are mixed is supplied to the boiler.

  According to the second aspect of the present invention, the makeup water is degassed in the first degassing processing section, and the degassed makeup water is stored in the makeup water storage section. On the other hand, the condensate is stored in the condensate storage unit and then introduced into the second deaeration processing unit. This condensate is deaerated in the second deaeration processor and then supplied to the makeup water reservoir. In the makeup water storage section, the degassed makeup water and the degassed condensate are mixed and secured as feed water, and this feed water is supplied to the boiler.

  According to the present invention, it is possible to reliably perform the deaeration process of the feed water in which the makeup water and the condensate are mixed, and to realize the power saving related to the deaeration process. As a result, corrosion of boilers, steam piping and condensate piping can be effectively suppressed without using water treatment agents such as oxygen scavengers and condensate treatment agents, or by using the minimum amount of water treatment agent. Moreover, the running cost concerning water treatment can be reduced.

  Next, an embodiment of the present invention will be described. The present invention is suitably implemented in a water supply system of a boiler device that is collecting condensate.

(First embodiment)
First, a first embodiment of a deaeration system according to the present invention will be described. The deaeration system according to the first embodiment mainly includes a first deaeration unit, a makeup water storage unit, and a second deaeration unit.

  The first deaeration unit performs a deaeration process on the makeup water to the boiler, and the first deaeration unit is connected to the makeup water storage unit via a makeup water supply path. That is, the makeup water deaerated in the first degassing section is supplied to the makeup water storage section via the makeup water supply path and stored.

  In this configuration, the makeup water supply path is preferably connected so as to supply makeup water to the lower portion of the makeup water storage section in order to prevent the makeup water deaerated from coming into contact with the atmosphere. If comprised in this way, the water supply of a lower dissolved oxygen concentration can be supplied to the said boiler.

  A lower portion of the makeup water storage unit is connected to the boiler through a water supply supply path. In order to supply the generated steam to load equipment such as heating equipment, drying equipment, and production equipment, the boiler is connected to the load equipment via a steam supply path, that is, steam piping. The load device is connected to a condensate recovery path, that is, one end side of a condensate pipe in order to recover condensed water generated by heat exchange of steam as condensate.

The second deaeration part is connected to the other end side of the condensate recovery path. That is, the condensate recovered via the condensate recovery path is directly introduced into the second deaeration unit, and the condensate is deaerated in the second deaeration unit. The second deaeration unit is connected to the makeup water storage unit through a condensate extraction path. That is, the condensate deaerated in the second deaeration unit is supplied to the make-up water storage unit via the condensate take-out path and mixed with the make-up water stored in the make-up water storage unit. It is configured.

  In this configuration, the condensate extraction path is preferably connected so as to supply condensate to a lower portion of the makeup water storage unit in order to prevent the degassed condensate from coming into contact with the atmosphere. Further, in order to uniformly mix the condensate and the makeup water, the inflow portion of the condensate and the inflow portion of the makeup water may be provided close to each other in the makeup water storage section. Further, as another configuration for uniformly mixing the condensate and the makeup water, a circulation path may be connected to the makeup water storage section, and a circulation pump may be provided in the circulation path. If comprised in this way, while being able to mix a condensate and make-up water uniformly using a water flow, the water supply of a lower dissolved oxygen concentration can be supplied to the said boiler.

  Here, the first deaeration unit and the second deaeration unit will be specifically described. The first deaeration unit can be used without any particular limitation as long as it is a deaeration device capable of processing normal temperature makeup water. Examples of the degassing device applicable as the first degassing unit include a membrane degassing device, a vacuum degassing device, and a nitrogen substitution degassing device.

  The membrane-type deaeration device bundles a plurality of hollow fiber-like polymer membranes having a characteristic of allowing gas such as oxygen to permeate but not liquid, and accommodates them in a housing. A deaeration module having a structure in which a part is sealed with a resin agent or the like is used. And the apparatus of the structure which reduces the dissolved gas contained in to-be-processed water by supplying to-be-processed water to one side of each said polymer film, and decompressing the other side of each said polymer film with a vacuum pump etc. It is.

  The vacuum deaerator first pressurizes the water to be treated and supplies it to a nozzle provided in the upper part of the treatment tank, and sprays the water to be treated from the upper part to the lower part in the treatment tank. And it is an apparatus of the structure which takes out treated water from the said processing tank, after reducing the dissolved gas contained in to-be-processed water by decompressing the inside of the said processing tank.

  The nitrogen substitution type deaerator first pressurizes the water to be treated and supplies it to a nozzle provided in the upper part of the treatment tank, and sprays the water to be treated from the upper part to the lower part in the treatment tank. Then, nitrogen gas is supplied into the treatment tank, and dissolved oxygen and dissolved carbon dioxide gas contained in the water to be treated are replaced with nitrogen gas and reduced, and then, while removing the treated water from the treatment tank, oxygen and The apparatus is configured to exhaust nitrogen gas containing carbon dioxide gas from the processing tank.

  Moreover, as another structure of the said nitrogen substitution type deaeration apparatus, first, to-be-processed water is pressurized and it supplies to a processing tank, distribute | circulating the inside of a pipe line continuously. Then, nitrogen gas is blown into the pipe line to bubbling or stirring the water to be treated, and after reducing dissolved oxygen and dissolved carbon dioxide gas with nitrogen gas and reducing the treated water from the treatment tank, A configuration in which nitrogen gas containing oxygen or carbon dioxide gas is exhausted from the pipe is also possible. Furthermore, a batch-type configuration is also possible in which the water to be treated is simply stored without circulating in the treatment tank, and bubbling or stirring is performed by blowing nitrogen gas into the water to be treated.

  The second degassing unit can be used without any limitation as long as it is a degassing device capable of treating condensate containing high temperature and suspended solids. Examples of the degassing device applicable as the second degassing unit include the vacuum degassing device and the nitrogen substitution degassing device.

Hereinafter, the operation of the deaeration system according to the first embodiment will be described. First, makeup water is deaerated in the first deaeration unit, and dissolved oxygen and dissolved carbon dioxide contained in the makeup water are reduced. This makeup water is supplied to the makeup water storage section via the makeup water supply path. Here, the first deaeration unit is controlled so as to operate only when makeup water is required. Therefore, the maximum processing amount can be set small, and the power consumption can be reduced.

  Next, the condensate recovered through the condensate recovery path is directly introduced into the second degassing part, and degassed in the second degassing part, so that the dissolved water contained in the condensate is dissolved. Oxygen and dissolved carbon dioxide are reduced. And this condensate is supplied to the said make-up water storage part via the said condensate extraction path | route. Here, the second deaeration unit is controlled so as to operate only when the condensate is recovered. As a result, the maximum processing amount can be set small, and the power consumption can be reduced.

  In the makeup water storage section, makeup water that has been degassed and condensate that has been degassed are mixed to ensure water supply with reduced dissolved oxygen and dissolved carbon dioxide gas. This water supply is supplied to the boiler via the water supply supply path. In the boiler, steam is generated by heating the stored feed water, that is, boiler water. Here, since dissolved oxygen in the boiler water is reduced in the boiler, corrosion of water pipes and headers, specifically pitting corrosion is effectively suppressed. In the boiler, since dissolved oxygen and dissolved carbon dioxide in boiler water are reduced, oxygen and carbon dioxide contained in the steam are reduced.

  The steam generated in the boiler is supplied to the load device via the steam supply path. This steam is changed into condensed water by heat exchange in the load device. The condensed water is recovered as condensate through the condensate recovery path and introduced into the second deaeration unit. Here, in the steam supply route and the condensate recovery route, oxygen and carbon dioxide contained in the steam are reduced, so that the amount of these gases dissolved in the condensed water is reduced, and the piping is corroded. Pitting corrosion and thinning corrosion are effectively suppressed.

  As described above, according to the first embodiment, it is possible to reliably perform the deaeration process of the feed water in which the makeup water and the condensate are mixed, and realize power saving related to the deaeration process. be able to. As a result, corrosion of boilers, steam pipes and condensate pipes can be effectively suppressed without using water treatment agents such as oxygen scavengers and condensate treatment agents, or by using the minimum amount of water treatment agent. The running cost for water treatment can be reduced.

(Second embodiment)
Next, a second embodiment of the deaeration system according to the present invention will be described. The deaeration system according to the second embodiment mainly includes a condensate storage unit in addition to the first deaeration unit, the makeup water storage unit, and the second deaeration unit described in the first embodiment. Yes. Here, detailed description of the same configuration as that of the first embodiment is omitted, and only a different configuration will be described.

  In the second embodiment, the other end side of the condensate recovery path is connected to the condensate reservoir. The bottom of the condensate storage unit is connected to the second deaeration unit through a condensate supply path. That is, after condensate recovered via the condensate recovery path is stored in the condensate storage part, the condensate is supplied to the second deaeration part via the condensate supply path, The degassing unit is configured to degas the condensate.

  In this configuration, the condensate recovery path is preferably connected so as to supply condensate to the lower part of the condensate reservoir in order to prevent air from being caught in the recovered condensate. If comprised in this way, re-dissolution of oxygen and a carbon dioxide gas to condensate will be suppressed, and a deaeration process can be efficiently performed in said 2nd process part.

The second deaeration unit is connected to the makeup water storage unit through a condensate extraction path. That is, the condensate deaerated in the second deaeration unit is supplied to the make-up water storage unit via the condensate take-out path and mixed with the make-up water stored in the make-up water storage unit. It is configured.

  Here, the makeup water storage section and the condensate storage section are not necessarily provided separately. For example, one tank is divided into two by a partition plate, and each of them is divided into the makeup water storage section and the recovery water storage section. You may comprise so that it may allocate to a water storage part. If comprised in this way, the installation space of the said makeup water storage part and the said condensate storage part can be reduced. Further, since the makeup water is heated by the heat of the condensate through the partition plate, the heat of the condensate can be efficiently recovered.

  In the above-described configuration, the first deaeration unit can be used without particular limitation as long as it is a deaeration device capable of processing normal temperature replenishment water, as in the first embodiment. Examples of the degassing device applicable as the first degassing unit include the membrane degassing device, the vacuum degassing device, and the nitrogen substitution degassing device.

  In addition, the second degassing unit can be used without any limitation as long as it is a degassing device capable of treating condensate containing high temperature and suspended substances as in the first embodiment. Examples of the degassing device applicable as the second degassing unit include the vacuum degassing device and the nitrogen substitution degassing device.

  Hereinafter, the operation of the deaeration system according to the second embodiment will be described. First, makeup water is deaerated in the first deaeration unit, and dissolved oxygen and dissolved carbon dioxide contained in the makeup water are reduced. This makeup water is supplied to the makeup water storage section via the makeup water supply path. Here, the first deaeration unit is controlled so as to operate only when makeup water is required. Therefore, the maximum processing amount can be set small, and the power consumption can be reduced.

  Next, the condensate recovered through the condensate recovery path is supplied to the condensate storage unit and stored. The stored condensate is supplied to the second deaeration unit via the condensate supply path, and is deaerated in the second deaeration unit, so that dissolved oxygen and dissolved oxygen contained in the condensate are discharged. Carbon dioxide gas is reduced. And this condensate is supplied to the said make-up water storage part via the said condensate extraction path | route. Here, the second deaeration unit is controlled so as to operate only when the condensate is recovered. Therefore, the maximum processing amount can be set small, and the power consumption can be reduced.

  In the makeup water storage section, makeup water that has been degassed and condensate that has been degassed are mixed to ensure water supply with reduced dissolved oxygen and dissolved carbon dioxide gas. This water supply is supplied to the boiler via the water supply supply path. In the boiler, steam is generated by heating the stored feed water, that is, boiler water. Here, since dissolved oxygen in the boiler water is reduced in the boiler, corrosion of water pipes and headers, specifically pitting corrosion is effectively suppressed. In the boiler, since dissolved oxygen and dissolved carbon dioxide in boiler water are reduced, oxygen and carbon dioxide contained in the steam are reduced.

  The steam generated in the boiler is supplied to the load device via the steam supply path. This steam is changed into condensed water by heat exchange in the load device. The condensed water is recovered as condensate through the condensate recovery path and introduced into the second deaeration unit. Here, in the steam supply route and the condensate recovery route, oxygen and carbon dioxide contained in the steam are reduced, so that the amount of these gases dissolved in the condensed water is reduced, and the piping is corroded. Pitting corrosion and thinning corrosion are effectively suppressed.

As described above, according to the second embodiment, it is possible to reliably perform the deaeration process of the feed water in which the makeup water and the condensate are mixed, and realize power saving related to the deaeration process. Can do. As a result, corrosion of boilers, steam piping and condensate piping can be effectively prevented without using water treatment agents such as oxygen scavengers and condensate treatment agents, or by using the minimum amount of water treatment agents. It can suppress and the running cost concerning water treatment can be reduced.

(First Example)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a schematic configuration diagram of a deaeration system according to the first embodiment. The deaeration system according to the first embodiment is connected to a water supply system of a boiler device, collects condensate (steam drain) in which steam is condensed, and supplies the boiler with supply water in which makeup water and condensate are mixed. Applicable to the case. In FIG. 1, the deaeration system 1 mainly includes a first deaeration unit 2, a makeup water storage unit 3, and a second deaeration unit 4.

  A makeup water supply path 5 is connected to the makeup water storage section 3, and a downstream end of the makeup water supply path 5 extends toward the bottom of the makeup water storage section 3. The makeup water supply path 5 is provided with a soft water device 6 and the first deaeration unit 2 in order from the upstream side.

  The water softener 6 removes hardness components (calcium ions and magnesium ions) from raw water such as tap water, industrial water, and groundwater using a cation exchange resin, and prevents scale formation in the boiler described later. Water treatment equipment. On the other hand, the first deaeration unit 2 is a membrane deoxygenation device provided with a predetermined number of deaeration modules (not shown). That is, the water from which the hardness component has been removed from the raw water, that is, the soft water, is deaerated in the first deaeration unit 2 and then supplied to the make-up water storage unit 3 via the make-up water supply path 5 as make-up water. It is configured to be supplied. The makeup water storage unit 3 is provided with a water level sensor 7 for detecting the level of the stored makeup water.

  The bottom of the makeup water storage unit 3 is connected to a boiler 8 through a feed water supply path 9, and the feed water supply path 9 is provided with a feed water pump 10. The boiler 8 is connected to the load device 11 through a steam supply path 12 (steam pipe) in order to supply the generated steam to the load device 11. The load device 11 is connected to one end side of a condensate recovery path 13 (condensate piping) in order to recover steam condensate as condensate. The condensate recovery path 13 is provided with a steam trap 14 and a temperature sensor 15 in order from the upstream side. The steam trap 14 is for discharging the condensate generated in the load device 11 and the steam supply path 12 using steam pressure. The temperature sensor 15 is for detecting whether or not condensate is recovered from the condensate recovery path 13.

  The second deaeration unit 4 is a vacuum type deaeration device in which a nozzle 17 is provided in the upper part of the treatment tank 16, and the nozzle 17 is connected to the other end side of the condensate recovery path 13. Further, an exhaust path 18 is connected to the upper portion of the processing tank 16 for vacuuming and exhausting the inside of the processing tank 16, and a vacuum pump 19 is provided in the exhaust path 18. That is, it is configured such that the condensate recovered through the condensate recovery path 13 is sprayed into the treatment tank 16 through the nozzle 17 and the deaeration process is performed by reducing the pressure in the storage tank 16. ing.

  The bottom of the treatment tank 16 is connected to the bottom of the makeup water storage unit 3 by a condensate extraction path 20, and a water supply pump 21 is provided in the condensate extraction path 20. That is, the condensate degassed in the treatment tank 16 is supplied to the make-up water storage unit 3 through the condensate extraction path 20 and mixed with the make-up water stored in the make-up water storage unit 3. And configured to generate water supply.

Hereinafter, the operation of the deaeration system 1 according to the first embodiment will be described. First, the raw water flowing through the makeup water supply path 5 is softened by ion exchange in the soft water device 6. This soft water is further deaerated in the first deaeration unit 2, that is, a membrane deaerator, so that dissolved oxygen and dissolved carbon dioxide contained in the makeup water are reduced. The deaerated soft water is supplied to the makeup water storage section 3 as makeup water and stored.

  Here, the operation of the first deaeration unit 2 is controlled based on the water level in the makeup water storage unit 3 detected by the water level sensor 7 and the operating state of the water supply pump 21. Specifically, when the water level in the makeup water storage unit 3 is less than a predetermined value and the water pump 21 is stopped, the stored makeup water is insufficient, and condensate is stored in the makeup water storage. It is determined that it is not supplied to the section 3. And based on this determination result, while performing the deaeration process of makeup water, it controls to supply this makeup water to the makeup water storage part 3.

  Next, during the combustion of the boiler 8, the condensate is recovered through the condensate recovery path 13 by the operation of the steam trap 14. This condensate is pressurized by steam pressure and sprayed into the treatment tank 16 through the nozzle 17. In the second degassing unit 4, by operating the vacuum pump 19, the inside of the processing tank 16 is decompressed, and dissolved oxygen and dissolved carbon dioxide contained in the condensate are removed. The dissolved oxygen and dissolved carbon dioxide gas removed from the condensate are exhausted out of the system via the exhaust path 18. The degassed condensate is stored in the lower part of the treatment tank 16. The condensate is taken out from the treatment tank 16 by operating the water pump 21 and supplied to the makeup water storage unit 3 through the condensate extraction path 20.

  Here, the operation of the vacuum pump 19 and the water pump 21 is controlled based on the water level in the storage tank 16 and the temperature in the condensate recovery path 13 detected by the temperature sensor 15. . Specifically, when the temperature in the condensate recovery path 13 is equal to or higher than a predetermined value, it is determined that condensate is recovered. Then, based on the determination result, the vacuum pump 19 is operated to control the deaeration process of the condensate. Further, when the water level in the storage tank 16 is equal to or greater than a predetermined value, it is determined that the degassed condensate is sufficiently stored and the operation of the water supply pump 21 is not hindered. Based on the determination result, the water pump 21 is operated to control the degassed condensate to be supplied to the makeup water storage unit 3.

  In the makeup water storage unit 3, the makeup water that has been degassed and the condensate that has been degassed are mixed to ensure water supply with reduced dissolved oxygen and dissolved carbon dioxide gas. This water supply is supplied to the boiler 8 through the water supply supply path 9 by operating the water supply pump 10 in accordance with the water level in the boiler 8. In the boiler 8, steam is generated by heating the stored feed water, that is, boiler water. The steam generated in the boiler 8 is supplied to the load device 11 through the steam supply path 12. This steam is changed into condensed water by heat exchange in the load device 11. The condensed water is recovered as condensate via the condensate recovery path 13 and supplied to the second deaeration unit 4.

(Second embodiment)
Next, a second embodiment of the present invention will be described in detail with reference to the drawings. FIG. 2 shows a schematic configuration diagram of a deaeration system according to the second embodiment. The deaeration system 22 according to the second embodiment includes a condensate storage unit 23 in addition to the first deaeration unit 2, the makeup water storage unit 3, and the second deaeration unit 4 described in the first example. It is mainly equipped with. In FIG. 2, the same reference numerals as those in the first embodiment denote the same members, and detailed description thereof will be omitted.

In the second embodiment, the other end side of the condensate recovery path 13 is connected to the condensate reservoir 23. The downstream end of the condensate recovery path 13 extends toward the bottom of the condensate reservoir 23.

  The bottom of the condensate reservoir 23 is connected to the nozzle 17 of the second deaeration unit 4 by a condensate supply path 24, and the condensate supply path 24 is provided with a pressurizing pump 25. Yes. That is, after condensate recovered via the condensate recovery path 13 is stored in the condensate reservoir 23, this condensate is supplied into the treatment tank 16 via the condensate supply path 24, The condensate is degassed in the treatment tank 16.

  The bottom of the treatment tank 16 is connected to the bottom of the makeup water storage unit 3 by a condensate extraction path 20, and a water supply pump 21 is provided in the condensate extraction path 20. That is, the condensate degassed in the treatment tank 16 is supplied to the make-up water storage unit 3 through the condensate extraction path 20 and mixed with the make-up water stored in the make-up water storage unit 3. And configured to generate water supply.

  The makeup water reservoir 3 is provided with a first water level sensor 26 for detecting the level of the stored makeup water. On the other hand, the condensate reservoir 23 is provided with a second water level sensor 27 for detecting the water level of the stored condensate.

  Hereinafter, the operation of the deaeration system 22 according to the second embodiment will be described. First, the raw water flowing through the makeup water supply path 5 is softened by ion exchange in the soft water device 6. This soft water is further deaerated in the first deaeration unit 2, that is, a membrane deaerator, so that dissolved oxygen and dissolved carbon dioxide contained in the makeup water are reduced. The deaerated soft water is supplied to the makeup water storage section 3 as makeup water and stored.

  Here, the operation of the first deaeration unit 2 is controlled based on the water level in the makeup water storage unit 3 detected by the first water level sensor 26 and the operating state of the water pump 21. Specifically, when the water level in the makeup water storage unit 3 is less than a predetermined value and the water pump 21 is stopped, the stored makeup water is insufficient, and condensate is stored in the makeup water storage. It is determined that it is not supplied to the section 3. And based on this determination result, while performing the deaeration process of makeup water, it controls to supply this makeup water to the makeup water storage part 3.

  Next, during the combustion of the boiler 8, the condensate is recovered through the condensate recovery path 13 by the operation of the steam trap 14 and is supplied to the condensate reservoir 23. When condensate is stored in the condensate reservoir 23, the pressurizing pump 25 is operated. This condensate is pumped to the second deaeration unit 4 via the condensate supply path 24 and sprayed into the treatment tank 16 via the nozzle 17. In the second degassing unit 4, by operating the vacuum pump 19, the inside of the processing tank 16 is decompressed, and dissolved oxygen and dissolved carbon dioxide contained in the condensate are removed. The dissolved oxygen and dissolved carbon dioxide gas removed from the condensate are exhausted out of the system via the exhaust path 18. The degassed condensate is stored in the lower part of the treatment tank 16. The condensate is taken out from the treatment tank 16 by operating the water pump 21 and supplied to the makeup water storage unit 3 through the condensate extraction path 20.

Here, the pressure pump 25, the vacuum pump 19, and the water pump 21 are based on the water level in the condensate reservoir 23 and the water level in the treatment tank 16 detected by the second water level sensor 27. Each operation is controlled. Specifically, when the water level in the condensate storage unit 23 is equal to or higher than a predetermined value, it is determined that the recovered condensate is sufficiently stored. Based on the determination result, the vacuum pump 19 and the pressurizing pump 25 are operated to control the degassing of the condensate. Further, when the water level in the treatment tank 16 is equal to or higher than a predetermined value, it is determined that the degassed condensate is sufficiently stored and the operation of the water supply pump 21 is not hindered. Based on the determination result, the water pump 21 is operated to control the degassed condensate to be supplied to the makeup water storage unit 3.

  In the makeup water storage unit 3, the makeup water that has been degassed and the condensate that has been degassed are mixed to ensure water supply with reduced dissolved oxygen and dissolved carbon dioxide gas. This water supply is supplied to the boiler 8 through the water supply supply path 9 by operating the water supply pump 10 in accordance with the water level in the boiler 8. In the boiler 8, steam is generated by heating the stored feed water, that is, boiler water. The steam generated in the boiler 8 is supplied to the load device 11 through the steam supply path 12. This steam is changed into condensed water by heat exchange in the load device 11. The condensed water is recovered as condensate via the condensate recovery path 13 and supplied to the condensate storage unit 23.

(Third embodiment)
Next, a third embodiment of the present invention will be described in detail with reference to the drawings. FIG. 3 shows a schematic configuration diagram of a deaeration system according to the third embodiment. The deaeration system 28 according to the third embodiment is a modification of the second embodiment, and includes the first deaeration unit 2, the makeup water storage unit 3, the second deaeration unit 4, and the condensate storage. The unit 23 is mainly provided. In FIG. 3, the same reference numerals as those in the first embodiment and the second embodiment denote the same members, and detailed description thereof will be omitted.

  The deaeration system 1 according to the third embodiment includes a tank 29. The inside of the tank 29 is divided into two by a partition plate 30, and each is assigned to the makeup water storage unit 3 and the condensate storage unit 23. The portion corresponding to the make-up water storage unit 3 is connected to the make-up water supply route 5, the water supply supply route 9, and the condensate take-out route 20, respectively. On the other hand, the condensate collection path 13 and the condensate supply path 24 are connected to a portion corresponding to the condensate storage section 23, respectively. Further, the first water level sensor 26 is provided in a portion corresponding to the makeup water storage unit 3, and the second water level sensor 27 is provided in a portion corresponding to the condensate storage unit 23. ing.

  The operation of the deaeration system 28 according to the third embodiment is the same as that of the second embodiment.

1 is a schematic configuration diagram of a deaeration system according to a first embodiment of the present invention. The schematic block diagram of the deaeration system which concerns on 2nd Example of this invention. The schematic block diagram of the deaeration system which concerns on 3rd Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Deaeration system 2 1st deaeration part 3 Makeup water storage part 4 2nd deaeration part 8 Boiler 22 Deaeration system 23 Condensate storage part 28 Deaeration system

Claims (2)

A degassing system for supplying degassed feed water to a boiler,
A first degassing unit for degassing the makeup water;
A makeup water storage section for storing makeup water that has been degassed;
A second degassing part for degassing the steam condensate generated in the boiler,
Supplying the condensate deaerated in the second deaeration unit to the makeup water storage unit;
A deaeration system for supplying a supply water in which makeup water and condensate are mixed to the boiler. A degassing system for supplying degassed feed water to a boiler,
A first degassing unit for degassing the makeup water;
A makeup water storage section for storing makeup water that has been degassed;
A condensate reservoir for storing condensate of steam generated in the boiler;
A second deaeration part for degassing the condensate in the condensate storage part,
Supplying the condensate deaerated in the second deaeration unit to the makeup water storage unit;
A deaeration system for supplying a supply water in which makeup water and condensate are mixed to the boiler.

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