JP5474610B2 - Equipment for supplying oxygen and decarbonated water for boilers - Google Patents

Description

  The present invention relates to a deoxygenation and decarbonated water supply device for a boiler that supplies water from which oxygen and carbonic acid components have been removed to a boiler.

  In boilers used in various chemical plants, factories, power plants, etc., heat exchangers in which dissolved gases such as oxygen and carbon dioxide contained in the water supply are arranged in the boiler body and in front of the boiler body This may cause corrosion of economizers and the like.

  In addition, carbonates and bicarbonates in feed water are pyrolyzed to produce carbon dioxide, which is transferred to the steam system, often corroding heat exchangers and piping that come into contact with steam and steam condensate. Will occur.

  If corrosion occurs in related equipment such as the boiler body, the heat exchanger or economizer, the steam / condensate line piping, or the heat exchanger that is placed in front of the boiler body, energy loss will occur due to steam leakage. Or repairing damaged parts such as pipes and heat exchangers may require a lot of money and time.

  Therefore, the dissolved gas is conventionally removed from the feed water to the boiler. As a device for removing dissolved gas, a heat degassing device, a vacuum degassing device, a membrane degassing device, and the like have been proposed. However, when these devices are used alone, dissolved gas in water can be removed, but ion components such as bicarbonate ions cannot be removed.

  Therefore, as a device for removing carbon dioxide components such as oxygen and carbon dioxide gas, bicarbonate ions, carbonate ions, etc. from the water and supplying water to demand areas such as boilers, deoxygenation and desorption for boilers as shown in FIG. A carbonated water supply device 10 has also been proposed.

  A conventional deoxygenation and decarbonated water supply device 10 for a boiler supplies an acidic liquid 11a to the feed water 2c, adjusts the pH of the feed water to acid, and supplies the feed water and nitrogen adjusted to acidity. A nitrogen-type deoxygenation / decarboxylation device 12 for contacting and removing oxygen and carbonic acid components, and pH neutralization for adjusting the pH to neutral or higher by adding alkaline liquid 13a to water from which oxygen and carbonic acid components have been removed in an acidic region Means 13. In addition, the arrow in FIG. 2 shows the flow direction of the liquid in piping, and the circle P means the pump which sends a liquid in the arrow direction.

  As a device similar to the deoxygenation and decarbonated water supply device 10 for a boiler, Patent Literature 1 is disclosed. Furthermore, patent document 2 is disclosed as what reuses nitrogen. Patent Document 3 is also disclosed as a deaerated water supply device.

JP 2003-047950 A JP 2001-129305 A JP 2003-300062 A

  In the conventional boiler deoxygenation and decarbonated water supply apparatus 10 as shown in FIG. 2, the pump 14 is driven according to the amount of water required for the boiler 6. This water supply is also stopped according to the water demand required for the boiler 6 or the water supply amount fluctuates. As described above, when the amount of water supplied to the nitrogen-type deoxygenation / decarboxylation device 12 changes, it becomes difficult to ensure a predetermined deoxygenation / decarboxylation capacity depending on the operating conditions. No water will be supplied to the boiler 6, causing corrosion to the boiler 6 and related equipment.

As a method for keeping the amount of water supplied to the nitrogen-type deoxygenation decarboxylation device 12 constant, as described in Patent Document 3, a part of the treated water of the deoxygenation and decarbonation water supply device 10 for the boiler is used. A method of returning to the supply water side of the boiler deoxygenation and decarbonated water supply apparatus 10 such as a water supply tank is also conceivable, but in this case, the acidic liquid 11a and the alkaline liquid 13a before and after the nitrogen-type deoxygenation decarboxylation apparatus 12 Will be repeated, and the salt concentration of the water supplied to the boiler 6 will rise gradually.

  When the salt concentration of boiler feed water rises and the salt concentration of water in the boiler body rises accordingly, obstacles such as corrosion, scale, and carry-over easily occur. In order to prevent failures, it has been necessary to increase the blow rate of the boiler 6 and to add a large amount of boiler treatment agents (anticorrosives and scale inhibitors).

  Accordingly, the present invention provides a deoxygenated and decarbonated water for a water-saving boiler that can stably supply water from which oxygen and carbonic acid components have been removed to the boiler, and that can keep the salt concentration of the feedwater to the boiler low. An object of the present invention is to provide a supply device.

  In order to solve the above-mentioned problems, the present invention includes a water supply tank for storing water, means for acidifying the pH of the water to be treated, and means for bringing the water to be treated into contact with nitrogen gas, and oxygen contained in the water to be treated And deoxygenated water supply device for boiler having oxygen and carbonic acid component removing means for removing carbonic acid component, and pH raising means for raising pH of water from which oxygen and carbonic acid component have been removed to neutral or higher And (1) a first water pipe connecting the water supply tank and the oxygen and carbonic acid component removing means via a check valve and a first pump in order, and (2) the oxygen and carbonic acid component removing means. And a second water pipe connecting the pH raising means via the second pump, (3) a third water pipe connecting the pH raising means and the demand point via the third pump, and (4) the above Check valve and first pump The first water pipe and the fourth water pipe connecting the second pump and the second water pipe between the pH raising means, and the oxygen and carbonic acid component removing means Water that exceeds the maximum water demand is always treated, and part of the water from which the oxygen and carbonic acid components have been removed is returned to the first water pipe via the fourth water pipe, and the water tank Backflow into the boiler is prevented by the check valve, and a deoxygenation and decarbonated water supply device for the boiler is provided.

  Further, the means for acidifying the pH of the water to be treated has phosphoric acid, polymerized phosphoric acid, phosphonic acid, carboxylic acid-based polymer, or one or more hydroxyl groups and carboxyl groups, or two or more carboxyl groups. The boiler is configured to supply deoxygenated and decarboxylated water for the boiler, which is a means for adding one or more selected from the organic acids to the water to be treated. Alternatively, the means for acidifying the pH of the water to be treated is means for bringing all or part of the water to be treated into contact with an H-type strongly acidic cation exchange resin, and A decarbonated water supply device was configured.

  Further, the configuration of the deoxygenation and decarboxylated water supply device for a boiler according to any one of the above, wherein the pH raising means adds an alkaline boiler chemical, and the alkaline boiler chemical is water. It was set as the structure of the deoxygenation and decarbonated water supply apparatus for the said boiler characterized by including the 1 type, or 2 or more types of chemical | medical agent chosen from sodium oxide, potassium hydroxide, and amines.

  In addition, the above-described deoxygenation for a boiler according to any one of the above, wherein a branch pipe is provided in the pH raising means or the third water supply pipe upstream of the third pump, and a pH measuring means is installed in the branch pipe. The deoxygenated water supply apparatus, and the deoxygenated and decarbonated water for the boiler, wherein the pH measuring means and the second water supply pipe upstream of the second pump are connected by a return pipe. The configuration of the supply device was adopted.

  Since this invention is the said structure, the following effect is exhibited. Regardless of boiler water demand, oxygen and carbonic acid component removal means is always supplied with a constant flow of water, so there is no risk of fluctuations in deoxygenation and decarbonation capacity due to on / off and flow fluctuations. The deoxygenated and decarboxylated water can be stably supplied to the boiler. In addition, since the oxygen and carbonic acid component removing means always treats water that exceeds the maximum water demand of the boiler, the boiler can always be supplied with sufficiently deoxygenated and decarboxylated water. Corrosion of related equipment can be effectively prevented.

Furthermore, in the unlikely event that problems such as oxygen and carbonic acid component removing means, clogging of piping, etc. occur, the water supply does not go through the oxygen and carbonic acid component removing means, and the fourth water pipe and pH raising means are connected from the water supply tank. Since the boiler is directly supplied to the boiler, it is possible to avoid an accident caused by depletion of water supplied to the boiler.

  In addition, since the pH raising means is in the rear stage of the circulation line constituted by a part of the first water pipe, a part of the second water pipe, and the fourth water pipe, acidic water usually flows through the circulation line. This means that the pH is not lowered or raised repeatedly due to the addition of the pH adjusting agent (acid solution or alkaline solution), and the salt concentration of the feed water to the boiler is not increased unnecessarily. Therefore, there is no need to increase the blow rate of the boiler, leading to water saving. Moreover, it is not necessary to add a large amount of boiler chemicals accompanying the increase in the salt concentration of boiler water. Furthermore, since a check valve is provided in the first water supply pipe between the water supply tank and the connection portion of the fourth water supply pipe, the acidic water flowing through the circulation line does not flow back into the water supply tank and fill up. The water tank need not be made of acid-resistant material.

  Furthermore, as means for acidifying the pH of the water to be treated of the oxygen and carbonic acid component removing means, by using an additive for the purpose of preventing corrosion and scale of the boiler, compared with the case of adding hydrochloric acid, sulfuric acid, etc. Useless increase in salt concentration is avoided. In addition, as a means for acidifying the pH of the water to be treated, a means for bringing all or part of the water to be treated into contact with the H-type strongly acidic cation exchange resin can increase the salt concentration of the feed water to the boiler. Further suppression can be achieved.

  In addition, since the pH raising means uses an alkaline boiler chemical originally intended to be added to the boiler, a useless increase in salt concentration can be avoided.

  In addition, a branch pipe is provided in the third water supply pipe upstream of the pH raising means or the third pump, and the pH measuring means is installed in the branch pipe, thereby monitoring whether the pH of the water supplied to the boiler is appropriate. be able to. It is also possible to feed back the pH measurement result to the pH raising means and control the pH of the water supplied to the boiler within an appropriate range. Further, by returning the outlet water of the pH measuring means to the circulation line, there is no water to be discarded and water can be saved.

It is a schematic diagram of an example of the deoxygenation and decarbonated water supply apparatus for boilers which is this invention. It is a schematic diagram of an example of the conventional deoxygenation and decarbonated water supply apparatus for boilers.

  Below, based on an accompanying drawing, the supply device for deoxygenation and decarbonated water for boilers which is the present invention is explained in detail.

  As shown in FIG. 1, a deoxygenation and decarbonated water supply device 1 for a boiler that is an example of the present invention includes a water supply line 2, an oxygen and carbonic acid component removal line 3, a pH raising means 4, and a water supply line. 5 and a pH measurement line 7, and a device for supplying deoxygenated and decarbonated water to the demand point of the boiler 6. The demand point is the boiler 6 itself, or a temporary storage tank, a heat exchanger, and other boiler-related equipment and facilities that require water supply installed upstream of the boiler 6.

  The water supply line 2 includes a water supply pipe 2a, a water supply tank 2b, a gate valve 2e, a check valve 2f, a T-shaped pipe 2g, and a first water supply pipe 2d in which a first pump 2h is interposed in the order described. The water supply 2c to the boiler 6 passes through the water supply pipe 2a and is temporarily stored in the water supply tank 2b. The stored water supply 2c is fed to the oxygen and carbonic acid component removing means 3a by driving the first pump 2h.

  The gate valve 2e is an on-off valve that controls the supply and stoppage of the water supply 2c, and is installed as necessary. While the deoxygenation and decarbonated water supply device 1 for the boiler is moving, the gate valve 2e is opened and the feed water 2c flows into the first water supply pipe 2d. The check valve 2f is a valve that prevents the reverse flow of water from which oxygen and carbonic acid components have been removed to the water supply tank 2b, and allows the water supply 2c to pass only from the water supply tank 2b side toward the boiler 6. The T-shaped pipe 2g branches the first water supply pipe 2d in the direction of the pH raising means 4.

  The oxygen and carbonic acid component removal line 3 includes an oxygen and carbonic acid component removing means 3a, a second water pipe 3b provided with a second pump 3c, a T-shaped pipe 3d, and a fourth water pipe 3e. The water from which oxygen and carbonic acid components have been removed from the water to be treated by the carbonic acid component removing means 3a is sent to the next pH raising means 4 by the second pump 3c, and part of it is returned to the first water supply pipe 2d. The

  In addition, to-be-processed water is the water 2c which flows through the 1st water supply pipe | tube 2d, and the water from which the oxygen and carbonate component which were returned to the 1st water supply pipe | tube 2d through the 4th water supply pipe | tube 3e were removed. In addition, water from which oxygen and carbonic acid components have been removed does not necessarily mean water from which oxygen and carbonic acid components have been completely removed, but is dissolved in water to a level that does not cause corrosion damage to the subsequent boiler and related equipment. It shows water with reduced oxygen and carbonic acid components.

  The oxygen and carbonic acid component removing means 3a is constituted by means for acidifying the pH of the water to be treated and means for bringing the water to be treated into contact with nitrogen gas. In FIG. 1, the oxygen and carbonic acid component removing means 3a is described as one in which the adjustment of the pH of the water to be treated to the acidic region and the contact with nitrogen gas are performed as one body.

  As a means for acidifying the pH of the water to be treated, an acid liquid is generally added to the water to be treated. A method of supplying the acid liquid before the means for bringing the water to be treated into contact with nitrogen gas, There is a method of supplying an acidic liquid within the means for bringing treated water into contact with nitrogen gas, etc., but the pH of the treated water is efficiently adjusted to the acidic range, and the carbonic acid component in the treated water is adjusted by contact with nitrogen gas. The method is not particularly limited as long as it can be efficiently removed.

  In order to efficiently remove the carbonic acid component in the water to be treated, it is necessary to adjust the pH of the water to be treated to 6.5 or less and to convert at least a part of the carbonic acid component in the water to be treated into free carbon dioxide. . The lower the pH, the higher the ratio of the carbonic acid component to free carbon dioxide, which is advantageous for removing the carbonic acid component when brought into contact with nitrogen gas. On the other hand, there is a problem that the apparatus is corroded by strongly acidic water and the amount of acid used for pH adjustment is increased. Therefore, the pH adjustment range is preferably 5.0 or more and 6.0 or less.

  Acidic solutions to be added include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid and polymerized phosphoric acid, 1-hydroxyethylidene-1,1-diphosphonic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, nitrilotri Phosphonic acid such as poly (methylenephosphonic acid), polyacrylic acid, polymaleic acid, copolymer of 2-acrylamido-2-methylpropanesulfonic acid and polyacrylic acid, bis (poly-2-carboxyethyl) phosphinic acid, etc. Or an aqueous solution of an organic acid such as succinic acid, gluconic acid, citric acid, malic acid, benzoic acid, oxalic acid, sorbic acid, formic acid, acetic acid, propionic acid, or butyric acid. These acids may be used alone or in combination of two or more.

  As acidic solution to be added, phosphoric acid, polymerized phosphoric acid, phosphonic acid, carboxylic acid-based polymer, or one or more hydroxyl groups and carboxyl groups such as succinic acid, gluconic acid, citric acid, malic acid, benzoic acid, oxalic acid, etc. When using one or two or more aqueous solutions selected from organic acids having two or more carboxyl groups, useless increase in salt concentration is avoided compared with the case of adding hydrochloric acid or sulfuric acid. In addition, since these function as anticorrosives and scale inhibitors for boilers, they are advantageous.

  Further, the means for acidifying the pH of the water to be treated is a means for bringing all or a part of the water to be treated into contact with the H-type strongly acidic cation exchange resin, and the means preceding the means for bringing the water to be treated into contact with nitrogen gas. It can also be installed. In this case, it is possible to further suppress an increase in the salt concentration of the feed water to the boiler.

  The means for bringing the water to be treated into contact with the nitrogen gas is not particularly limited as long as the nitrogen gas and the water to be treated can be efficiently brought into contact with each other to replace the nitrogen gas, oxygen and carbon dioxide. For example, a method in which nitrogen gas is bubbled into the water to be treated, a method in which water to be treated is sprayed and dropped from the upper part of the tower via a mixing element, and nitrogen gas is supplied from the lower part to make contact, or a combination of both. Various methods conventionally used, such as a method, can be used. Details are described in JP-A No. 2004-261691, JP-A No. 2005-95791, and the like.

  There is no restriction | limiting in particular as a nitrogen gas source, For example, the nitrogen cylinder etc. which stored liquid nitrogen can be used. In addition, in order to avoid the problem of oxygen deficiency due to excessive nitrogen gas flowing out into the facility, a type of supplying nitrogen gas by separating nitrogen in the air is preferable. As a means for separating nitrogen from the air, for example, a PSA (Pressure Swing Adsorption) method or a means using a nitrogen separation membrane can be used.

  The T-shaped pipe 3d is installed at the rear stage of the second pump 3c of the second water supply pipe 3b, one of which connects the second water supply pipe 3b to the pH raising means 4, and the other is the T-shaped pipe of the first water supply pipe 2d. It connects to 2g via the 4th water pipe 3e. Thereby, the water from which the oxygen and carbonic acid components in the second water supply pipe 3 b have been removed is sent to the pH raising means 4 according to the water demand at the demand location of the boiler 6 and supplied to the boiler 6. On the other hand, the water from which excess oxygen and carbonic acid components have been removed relative to the water demand at the demand location of the boiler 6 is returned to the first water pipe 2d by the second pump 3c through the fourth water pipe 3e. .

  Although the pH of the water from which oxygen and carbonic acid components have been removed is acidic, the water from which oxygen and carbonic acid components have been removed does not flow back into the water supply tank 2b due to the effect of the check valve 2f. If it flows backward to the water supply tank 2b, acidic water will fill the water supply tank 2b, and corrosion will easily occur on the inner surface of the water supply tank 2b.

  As a result, part of the water from which oxygen and carbonic acid components flowing through the second water pipe 3b are removed circulates through the fourth water pipe 3e, a part of the first water pipe 2d, and a part of the second water pipe 3b. It will be. These pipes are also called circulation lines.

  The pH raising means 4 adjusts the water from which the acidic oxygen and carbonic acid components have been removed through the oxygen and carbonic acid component removing line 3 to a pH of neutral or higher. This is because if the water from which the acidic oxygen and carbonic acid components have been removed is supplied to the boiler 6 as it is, the boiler can and the attached piping equipment may be corroded. The preferred pH range for boiler feed water varies depending on the type of boiler, but is generally in the range of 7.0 to 9.0. Therefore, when supplying the outlet water of the pH raising means 4 directly to the boiler, this pH range is used as a guide. The pH of the water from which oxygen and carbonic acid components have been removed is raised by the pH raising means 4. The water whose pH is adjusted by the pH raising means 4 may be simply referred to as treated water.

  As a means for raising the pH, it is common to add an alkaline liquid to the water to be treated. As an alkaline solution to be added, in addition to general alkaline agents such as sodium hydroxide and potassium hydroxide, sodium carbonate, trisodium phosphate, various amines such as alkylamine, aminomethylpropanol and morpholine, and sugars Additives to boilers in general, such as reaction products of alkali hydroxide, reaction products of lignin and alkali hydroxide, reaction products of tannin and alkali hydroxide, reaction products of gallic acid and alkali hydroxide It is possible to use an aqueous solution of one or more kinds of substances showing alkalinity. In particular, sodium hydroxide, potassium hydroxide, and amines are preferable because they have a high effect of increasing the pH when added in a small amount.

  In this invention, the pH raising means 4 is arrange | positioned in the position which processes only the supply water sent to the demand location of the boiler 6 among the water from which oxygen and the carbonic acid component were removed. Thereby, the water from which excess oxygen and carbonic acid components are removed without being supplied to the demand point of the boiler 6 circulates in the circulation line while maintaining the acidic state without passing through the pH raising means 4. Accordingly, the salt concentration of the water supplied to the boiler 6 is unnecessarily increased without repeatedly decreasing and increasing the pH due to the addition of a pH adjusting agent (acidic solution, alkaline solution) with respect to the water flowing through the circulation line. There is no. Moreover, the usage-amount of an acidic liquid and an alkaline liquid can be reduced.

  The water supply line 5 is provided in the third water supply pipe 5 a that connects the pH raising means 4 and the demand point of the boiler 6, and from the third pump 5 b that supplies the treated water to the demand point of the boiler 6. Become.

  The pH measurement line 7 includes a branch pipe 7a, a pH measurement unit 7b, a pH measuring device 7c, and a return pipe 7d. The pH measurement line 7 is provided as necessary and branches a part of the treated water that has passed through the pH raising means 4. The pH value of the treated water flowing through the pipe 7a is measured.

  The branch pipe 7a connects the pH raising means 4 or the third water supply pipe 5a upstream of the third pump 5b and the pH measuring unit 7b. Further, the pH measuring unit 7b may be provided in the branch pipe 7a or separately from the branch pipe 7a. FIG. 1 shows an embodiment in which the branch pipe 7a is branched from the pH raising means 4 and a part of the treated water is allowed to flow to the pH measuring unit 7b provided separately from the branch pipe 7a.

  The return pipe 7d connects the pH measurement unit 7b and the second water supply pipe 3b upstream of the second pump 3c. If the pH measuring unit 7b is not provided separately, the branch pipe 7a and the return pipe 7d are a single connected pipe.

  Moreover, you may discard the treated water which measured pH by the pH measurement part 7b, without providing the return piping 7d. On the other hand, by providing the return pipe 7d, the treated water can be reused as the water supply for the demand point of the boiler 6, and the water can be saved.

  By providing the pH measurement line 7, it becomes possible to grasp and manage the pH value of the treated water supplied from the pH raising means 4 to the demand point of the boiler 6. Thereby, based on the measurement data of the pH measuring device 7c, when it is determined that the pH value of the treated water is not adjusted to be neutral or higher, an alarm is generated or a warning light blinks. By notifying the water pH abnormality, it is possible to appropriately take measures to prevent the supply of acidic water to the boiler 6. Furthermore, automatic control for increasing or decreasing the amount of alkaline liquid added in the pH raising means 4 by using the measurement data obtained by the pH measuring device 7c as a control signal is also possible.

  The water supply 2c of the water supply tank 2b is not directly supplied to the boiler 6 through the fourth water supply pipe 3e without passing through the oxygen and carbonic acid component removing means 3a, and is always constant in the oxygen and carbonic acid component removing means 3a. In order to supply water at a flow rate, the discharge capacities of the first pump 2h and the second pump 3c need to be set larger than the discharge capacities of the third pump 5b. For example, the discharge capacity of the first and second pumps 2h and 3c may be set to about 1.1 to 1.5 times the discharge capacity of the third pump 5b.

  In the boiler deoxygenation and decarbonated water supply apparatus 1 according to the present invention thus configured, the amount of water to be treated by the oxygen and carbonic acid component removing means 3a varies depending on the load of the boiler 6 and is necessary water. In order to be able to cope with fluctuations in demand, it is set in excess of the maximum water demand of the boiler 6. Therefore, regardless of the water demand of the boiler 6, the oxygen and carbonic acid component removing means 3a is always supplied with a constant flow of water, so there is no possibility that the deoxygenation and decarbonation capacity will fluctuate due to start / stop and flow rate fluctuations. Water that has been sufficiently deoxygenated and decarboxylated can be stably supplied to the boiler 6. Further, since the oxygen and carbonic acid component removing means 3a always treats water exceeding the maximum water demand of the boiler 6, the boiler 6 can be supplied with sufficiently deoxygenated and decarboxylated water. The corrosion of the boiler 6 and related equipment can be effectively prevented.

  Furthermore, in the unlikely event that problems such as oxygen and carbonic acid component removing means 3a and piping clogging occur, the water supply 2c of the water supply tank 2b does not pass through the oxygen and carbonic acid component removing means 3a, and the first water pipe 2d. Is supplied directly to the boiler 6 via a part of the fourth water supply pipe 3e (white triangle in FIG. 1), a part of the second water supply pipe 3b, the pH raising means 4 and the water supply line 5. Accidents caused by the depletion of the water supply can be avoided.

  Even if the demand point is not the boiler 6 and the boiler-related equipment and equipment, but is equipment or equipment that requires other oxygen and carbonated component removal water, the deoxygenation and decarbonated water for the boiler according to the present invention. The supply device 1 can be used as a water supply device.

  The deoxygenation and decarbonated water supply device for boilers according to the present invention can be used as a stable water supply device for boilers used in various factories and the like, and can reduce the amount of pH adjusting chemical used. The salt concentration of the water supplied to the location can be kept low, and the amount of boiler chemicals used can be reduced. Furthermore, there is no waste of water supply and it contributes to water saving.

DESCRIPTION OF SYMBOLS 1 Boiler deoxygenation and decarbonated water supply device 2 Water supply line 2a Water supply pipe 2b Water supply tank 2c Water supply 2d First water supply pipe 2e Gate valve 2f Check valve 2g T-shaped pipe 2h First pump 3 Oxygen and carbonic acid component removal Line 3a Oxygen and carbonic acid component removing means 3b Second water pipe 3c Second pump 3d T-shaped pipe 3e Fourth water pipe 4 pH raising means 5 Water line 5a Third water pipe 5b Third pump 6 Boiler 7 pH measurement line 7a Branch Pipe 7b pH measuring unit 7c pH measuring device 7d Return pipe 10 Boiler deoxygenation and decarboxylated water supply device 11 pH adjusting means 11a Acidic liquid 12 Nitrogen type deoxygenating decarboxylation apparatus 13 pH neutralizing means 13a Alkaline liquid 14 Pump

Claims (7)

An oxygen and carbonic acid component for removing oxygen and carbonic acid components contained in the water to be treated, comprising a water supply tank for storing the water supply, means for acidifying the pH of the water to be treated and means for bringing the water to be treated into contact with nitrogen gas A deoxygenation and decarbonated water supply device for a boiler having a removing means and a pH raising means for raising the pH of water from which oxygen and carbonic acid components have been removed to a neutral or higher level,
further,
(1) a first water pipe connecting the water supply tank and oxygen and carbonic acid component removing means via a check valve and a first pump in order;
(2) a second water pipe connecting the oxygen and carbonic acid component removing means and the pH raising means via a second pump;
(3) a third water pipe connecting the pH raising means and the demand point via a third pump;
(4) having a fourth water pipe connecting the first water pipe between the check valve and the first pump and the second water pipe between the second pump and the pH raising means;
In the oxygen and carbonic acid component removing means, water exceeding the maximum water demand at the demand point is always treated, and a part of the water from which the oxygen and carbonic acid components have been removed passes through the fourth water pipe. An apparatus for supplying deoxygenated and decarbonated water for a boiler, wherein the deoxygenated and decarbonated water for a boiler is returned to the first water supply pipe, and the reverse flow to the water supply tank is prevented by the check valve. The means for acidifying the pH of the water to be treated is phosphoric acid, polymerized phosphoric acid, phosphonic acid, a carboxylic acid polymer, or an organic compound having one or more hydroxyl groups and carboxyl groups, or two or more carboxyl groups. The apparatus for supplying deoxygenated and decarbonated water for a boiler according to claim 1, characterized in that it is means for adding one or more selected from acids to treated water. The means for acidifying the pH of the water to be treated is a means for bringing all or part of the water to be treated into contact with an H-type strongly acidic cation exchange resin. Deoxygenated and decarbonated water supply device. The apparatus for deoxygenating and decarboxylated water for a boiler according to any one of claims 1 to 3, wherein the pH raising means adds an alkaline boiler chemical. 5. The boiler deoxygenation and decarboxylation according to claim 4, wherein the alkaline boiler chemical includes one or more chemicals selected from sodium hydroxide, potassium hydroxide, and amines. Water supply device. 6. The branching pipe is provided in the third water supply pipe upstream of the pH raising means or the third pump, and the pH measuring means is installed in the branching pipe according to any one of claims 1 to 5. Equipment for deoxygenation and decarbonated water for boilers. The apparatus for supplying deoxygenated and decarboxylated water for a boiler according to claim 6, wherein the pH measuring means and the second water supply pipe upstream of the second pump are connected by a return pipe.

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