WO2020031667A1 - Acid electrical conductivity measurement device and method, and steam turbine plant - Google Patents

Abstract

This acid electrical conductivity measurement device and method and steam turbine plant comprise a measurement-impairing-substance removal device (101) for vaporizing and removing a measurement-impairing substance included in feed water (W) by heating and boiling the feed water (W), a cation exchange device (102) functioning as a cation removal device for removing cations from the feed water (W) boiled by the measurement-impairing-substance removal device (101), and a first acid electrical conductivity meter (103) for measuring the acid electrical conductivity of feed water W from which cations have been removed by the cation exchange device (102).

Description

Apparatus and method for measuring acid electrical conductivity and steam turbine plant

The present invention relates to, for example, an acid conductivity measuring device and method for measuring acid conductivity of feed water in a steam turbine plant, and a steam turbine plant to which the acid conductivity measuring device is applied. .

In combined cycle power generation, a gas turbine is first driven by using natural gas or the like as a fuel, and then an exhaust heat recovery boiler collects the exhaust gas of the gas turbine to generate steam, which is then used to drive the steam turbine for combined use. This is to generate electricity. The combined cycle plant is a power plant for executing the combined cycle power generation.

By the way, in the combined cycle plant, the used steam that drives the steam turbine is cooled using seawater in a condenser to be condensed and returned to the exhaust heat recovery boiler. In the condenser, if the cooling pipe through which the seawater flows is damaged for some reason, the seawater may enter the condensate. Then, while the seawater component is concentrated in the drum of the evaporator in the water supply system of the waste heat recovery boiler, magnesium chloride is hydrolyzed to generate magnesium hydroxide and precipitate. This magnesium hydroxide can produce scaling on the inner wall of the water supply pipe, causing failure events such as heat transfer inhibition and corrosion. In addition, hydrochloric acid is generated by chloride ions released from magnesium chloride, which may lower the pH of the drum water and corrode the water supply pipe.

Therefore, leakage of seawater to the water supply is detected by measuring the acid conductivity of the water supply flowing through the water supply system. A general acid electric conductivity measuring device measures the acid electric conductivity of a feed water after converting cations contained in the feed water into hydrogen ions by passing the feed water through a cation exchange resin. Then, based on the measured acid electric conductivity, mixing of seawater into the water supply is detected. By the way, carbon dioxide is brought into the water supply and dissolved by the vacuum break of the condenser or the makeup water to the water supply system. Since the measuring device for acid electric conductivity measures carbon dioxide as carbonate ions, the acid electric conductivity of feed water becomes high. Therefore, a conventional acid conductivity measuring device removes the cations of the feed water using a cation exchange resin, and then heats and boiles the feed water to vaporize and remove carbon dioxide, which is an interfering substance. The electrical conductivity is measured. Examples of such a technique include those described in Non-Patent Document 1 and Patent Document 1.

JIS {8224: 2016} Boiler water supply and boiler water-Test methods JP-A-2015-148411

By the way, in order to suppress corrosion of the piping in the water supply system, the pH of the water supply is increased by adding a pH adjuster to the water supply to make the water supply alkaline. Therefore, when feed water is passed through the cation exchange resin using a conventional acid conductivity measuring device, the cation exchange resin adsorbs the pH adjuster in the feed water as cations (NH ₄ ⁺ ). Then, the amount of cations adsorbed by the cation exchange resin increases, the life of the cation exchange resin decreases, and the frequency of exchange of the cation exchange resin increases. As a result, the material cost and the processing cost increase, and the work of replacing the cation exchange resin by the operator increases, and the workability decreases.

An object of the present invention is to solve the above-described problems, and to reduce the frequency of replacement by extending the life of the apparatus, thereby suppressing an increase in cost and improving the workability of the measurement operation. And a method and a steam turbine plant.

To achieve the above object, the acid conductivity measuring device of the present invention is a measuring interfering substance removing device that removes a measuring interfering substance contained in the feed water by vaporizing the feed water by heating and boiling the feed water, A cation removing device for removing cations from the feed water from which the measurement disturbing material has been removed by the measurement disturbing material removing device, and a first acid for measuring the acid conductivity of the feed water from which the cations have been removed by the cation removing device. And an electric conductivity meter.

Therefore, the feedwater is first heated and boiled by the measurement interfering substance removing device, and is separated and removed by vaporizing the measuring interfering substance such as the pH adjuster contained in the feedwater, and then the cation removing device. Since the cations are removed, the first acid conductivity meter can accurately measure the acid conductivity of the feedwater from which the interfering substances and the cations have been removed. In addition, since the measurement interfering substances such as the pH adjuster are vaporized and removed from the feed water in advance, the amount of the measurement interfering substances to be removed by the cation removing device can be reduced, and the service life can be prolonged. The size of the device can be reduced. As a result, it is possible to suppress an increase in cost by reducing the replacement frequency of the cation removing device, and to improve the workability of the work of measuring the acid conductivity.

The acid conductivity measuring device of the present invention is characterized in that a cooling device is provided for cooling the feedwater discharged from the measuring interfering substance removing device.

Therefore, the feed water heated and boiled by the measurement interfering substance removing device is cooled by the cooling device and then supplied to the cation removing device, so that the cations can be properly removed and the cation removing device can be removed. Damage can be suppressed.

In the acid conductivity measuring device of the present invention, the cooling device performs heat exchange between water supplied to the measurement interfering substance removing device and water supplied from the measuring interfering substance removing device. It is characterized by being a vessel.

Therefore, by using the feed water supplied to the measurement interfering substance removing device as a cooling medium, heat is recovered from the heated feed water and the feed water supplied to the measuring interfering substance removing device is heated, and the heat is effectively used. , And the structure can be simplified by eliminating the need for another cooling medium.

In the acid conductivity measuring device of the present invention, a temperature measuring device for measuring the temperature of the feed water heated by the measuring interfering substance removing device, and the measuring interfering substance based on the temperature of the feed water measured by the temperature measuring device And a temperature controller for controlling the heating temperature of the feed water by the removing device.

Therefore, by controlling the heating temperature of the feed water by the measurement interfering substance removing device to an appropriate temperature, measurement interfering substances such as a pH adjuster contained in the feed water can be efficiently vaporized, and the vaporization of the feed water itself is suppressed. Thus, an appropriate amount of water can be supplied to the cation removing device.

In the acid conductivity measuring device of the present invention, the measuring interfering substance removing device, a container provided with a supply unit in the lower part and a discharge unit provided in the upper part, a heater for heating water supply in the container, An inert gas supply device for supplying an inert gas to the water supply in the container.

Therefore, the water supplied from the lower part into the container is heated by the heater, the measurement interfering substances are vaporized and separated, and then discharged from the upper discharge part. At this time, when the inert gas is supplied to the water supply in the container by the inert gas supply device, when the bubble of the inert gas rises in the water supply, the measurement interfering substance is taken into the bubble of the inert gas. As a result, the measurement interfering substances contained in the feed water can be efficiently separated and removed.

In the acid conductivity measuring device of the present invention, the measuring interfering substance removing device includes a container provided with a supply unit at a lower part and a discharge unit provided at an upper part, and a heater for heating water supply in the container. The discharge unit has a feedwater discharge unit that overflows and discharges feedwater, and a measurement-disturbance substance discharge unit that discharges a measurement-disturbance substance vaporized from the feedwater, and a decompression device is connected to the measurement-disturbance substance discharge unit. It is characterized by being done.

Therefore, the supply water supplied from the lower part into the container is heated by the heater, the measurement interfering substances are vaporized and separated, and then overflowed and discharged from the upper supply water discharge part, while the measurement water separated from the supply water is discharged. The interfering substances are discharged from the upper measuring interfering substance discharge. At this time, a negative pressure acts on the measurement interfering substance discharge section by the pressure reducing device, whereby the measurement interfering substance separated in the container can be sucked into the measurement interfering substance discharge section and can be efficiently discharged.

The acid conductivity measuring device of the present invention is characterized in that a second acid conductivity meter for measuring the acid conductivity of the feedwater discharged from the measuring interfering substance removing device is provided.

Therefore, the second acid conductivity meter can measure the acid conductivity of the feedwater from which the interfering substances have been removed with high accuracy.

酸 The acid conductivity measuring device of the present invention is characterized in that an electric conductivity meter for measuring the electric conductivity of feed water before being supplied to the measuring interfering substance removing device is provided.

Therefore, the concentration of the pH adjuster can be measured by measuring the electric conductivity of the feed water before the electric conductivity meter is supplied to the measurement interfering substance removing device.

Further, the method for measuring the acid conductivity of the present invention comprises a step of removing a measurement interfering substance, which vaporizes and removes a measurement interfering substance contained in the feed water by heating and boiling the feed water, and a step of removing cations from the heated boiling water. And a step of measuring an acid conductivity of the feedwater from which the cations have been removed.

Therefore, first, when the feed water is heated and boiled, a measurement interfering substance such as a pH adjuster contained in the feed water is vaporized and separated and removed, and then the pH adjuster is removed, so that the measurement interfering substance is removed. The acid conductivity of feed water from which substances and cations have been removed can be measured with high accuracy. Then, since the measurement interfering substance such as the pH adjuster is vaporized and removed from the feed water in advance, the amount of the measurement interfering substance to be removed in the cation removing step can be reduced, and the life of the apparatus can be extended. As a result, it is possible to suppress an increase in cost by reducing the replacement frequency of the device, and to improve the workability of the measurement operation of the acid electric conductivity.

Also, the steam turbine plant of the present invention includes an exhaust heat recovery boiler that generates steam by exhaust heat of exhaust gas, a steam turbine driven by the steam generated by the exhaust heat recovery boiler, and a steam discharged from the steam turbine. A condenser for returning feedwater produced by cooling the wastewater to the waste heat recovery boiler, and a measuring device for measuring the acid electric conductivity provided in a feedwater system of the feedwater cooled by the condenser. It is a feature.

Therefore, by providing an acid conductivity measuring device in the water supply system, the acid conductivity of the feed water can be measured with high accuracy, and the amount of measurement interfering substances removed by the cation removal device is reduced. Life can be extended. As a result, it is possible to suppress an increase in cost by reducing the replacement frequency of the cation removing device, and to improve the workability of the work of measuring the acid conductivity.

ADVANTAGE OF THE INVENTION According to the measuring apparatus and method of the acid electric conductivity of this invention, and a steam turbine plant, while increasing the life of an apparatus and reducing the frequency of replacement, increase in cost can be suppressed and workability of measurement work can be suppressed. Improvement can be achieved.

FIG. 1 is a schematic configuration diagram showing a combined cycle plant to which the acid conductivity measuring device of the present embodiment is applied. FIG. 2 is a schematic diagram showing a measuring device of the acid electric conductivity. FIG. 3 is a schematic view showing a measurement interfering substance removing device in the acid conductivity measuring device. FIG. 4 is a schematic diagram illustrating a modification of the measurement interfering substance removing device in the acid conductivity measuring device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of an acid conductivity measuring device and method and a steam turbine plant according to the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the present invention is not limited by the embodiments, and when there are a plurality of embodiments, the invention includes those configured by combining the embodiments.

In this embodiment, the acid conductivity measuring device and method of the present invention are applied to a combined cycle plant as a steam turbine plant. Here, the steam turbine plant is a plant having a power generation function using a steam turbine, and is a plant that includes not only a plant that generates power using a single steam turbine but also a combined cycle plant that combines a steam turbine with other power generation means. is there. FIG. 1 is a schematic configuration diagram showing a combined cycle plant to which the acid conductivity measuring device of the present embodiment is applied.

In the present embodiment, as shown in FIG. 1, the combined cycle plant 10 includes a gas turbine 11, an exhaust heat recovery boiler (HRSG) 12, a steam turbine 13, and a generator 14.

The gas turbine 11 includes a compressor 21, a combustor 22, and a turbine 23. The compressor 21 and the turbine 23 are connected to each other by a rotor (rotary shaft) 24 so as to be integrally rotatable. The compressor 21 compresses the air A taken in from the air intake line L1 to generate compressed air AC. The combustor 22 mixes and burns the compressed air AC supplied from the compressor 21 through the compressed air supply line L2 and the fuel gas F supplied from the fuel gas supply line L3. The turbine 23 is rotationally driven by the combustion gas FG supplied from the combustor 22 through the combustion gas supply line L4.

The exhaust heat recovery boiler 12 generates steam (superheated steam) S by exhaust heat of the exhaust gas EG discharged from the gas turbine 11 (turbine 23) via the exhaust gas discharge line L5. The exhaust heat recovery boiler 12 includes a low-pressure unit 41, a medium-pressure unit 42, a high-pressure unit 43, and a reheater 44, which will be described later. The exhaust heat recovery boiler 12 recovers heat from the exhaust gas EG in the order of the high pressure unit 43, the medium pressure unit 42, and the low pressure unit 41 by transferring the exhaust gas EG supplied from the gas turbine 11 upward. S is generated. The stack 45 is connected to the exhaust heat recovery boiler 12 via an exhaust gas discharge line L6 that discharges the used exhaust gas EG that has generated the steam S.

The steam turbine 13 is driven by the steam S generated by the exhaust heat recovery boiler 12. The steam turbine 13 has a high-pressure turbine 31, an intermediate-pressure turbine 32, and a low-pressure turbine 33. The high-pressure turbine 31, the medium-pressure turbine 32, and the low-pressure turbine 33 are connected on a rotating shaft 34, and the rotating shaft 34 is connected to the rotor 24 of the gas turbine 11 in a straight line. And the generator 14 is connected on the rotating shaft 34. The steam turbine 13 is provided with a condenser 35 for cooling the steam that has driven the low-pressure turbine 33. The condenser 35 cools the used steam S discharged from the low-pressure turbine 33 into condensate water (water supply W), and is provided with a cooling water line L7 for cooling the steam with seawater SW. . The condenser 35 supplies the generated condensed water as the water supply W to the exhaust heat recovery boiler 12 via the water supply line L11. The water supply line L11 is provided with a condensate pump 36, a ground condenser 37, a water supply preheater 38, and a deaerator 39.

In the heat recovery steam generator 12, the low pressure unit 41 includes a low pressure economizer 51, a low pressure drum 52, a low pressure evaporator 53, and a low pressure superheater. The water supply line L11 is provided with a low-pressure water supply line L12 branching from the downstream side of the deaerator 39, and the water supply W is sent to the low-pressure economizer 51 via the low-pressure water supply line L12. The low-pressure water supply line L12 is provided with a low-pressure water supply pump 55. The low-pressure economizer 51 heats the feedwater W, and the heated feedwater W is sent to the low-pressure drum 52. The low-pressure evaporator 53 heats the supply water W (hereinafter, drum water W1) of the low-pressure drum 52 and returns it to the low-pressure drum 52. The low-pressure steam LS of the low-pressure drum 52 is sent to a low-pressure superheater 54 where it is superheated.

The medium pressure unit 42 includes a medium pressure economizer 61, a medium pressure drum 62, a medium pressure evaporator 63, and a medium pressure superheater 64. Like the low-pressure water supply line L12, the water supply line L11 is provided with a medium-pressure water supply line L13 branching from the downstream side of the deaerator 39, and the water supply W is connected to the medium-pressure node via the medium-pressure water supply line L13. It is sent to the charcoal 61. The medium pressure water supply line L13 is provided with a medium pressure water pump 65. The medium pressure economizer 61 heats the feedwater W, and the heated feedwater W is sent to the intermediate pressure drum 62. The medium-pressure evaporator 63 heats the supply water W (hereinafter, drum water W2) of the medium-pressure drum 62 and returns the same to the medium-pressure drum 62. The medium-pressure steam MS of the medium-pressure drum 62 is sent to a medium-pressure superheater 64, where it is heated.

The high-pressure unit 43 includes a high-pressure economizer 71, a high-pressure drum 72, a high-pressure evaporator 73, and a high-pressure superheater 74. The medium-pressure water supply line L13 is provided with a high-pressure water supply line L14 branching downstream from the medium-pressure water supply pump 65, and the water supply W is sent to the high-pressure economizer 71 via the high-pressure water supply line L14. The high-pressure economizer 71 heats the feedwater W, and the heated feedwater W is sent to the high-pressure drum 72. The high-pressure evaporator 73 heats the feed water W (hereinafter, drum water W3) of the high-pressure drum 72 and returns it to the high-pressure drum 72. The high-pressure steam HS of the high-pressure drum 72 is sent to a high-pressure superheater 74, where it is superheated.

A high-pressure steam supply line L15 for supplying the high-pressure steam HS of the high-pressure superheater 74 to the high-pressure turbine 31 is provided, and the medium-pressure steam MS used in the high-pressure turbine 31 and reduced in pressure is returned to the reheater 44. A steam recovery line L16 is provided. The high-pressure steam supply line L15 is provided with a high-pressure main steam stop valve 75. Further, an intermediate-pressure steam supply line L17 for supplying the intermediate-pressure steam MS to the intermediate-pressure steam recovery line L16 is provided. Further, a medium-pressure steam supply line L18 for supplying the medium-pressure steam MS superheated by the reheater 44 to the medium-pressure turbine 32 is provided, and the low-pressure steam LS used by the medium-pressure turbine 32 and reduced in pressure is supplied to the low-pressure turbine A low-pressure steam transport line L19 for transporting the low-pressure steam to L33 is provided. The medium pressure steam supply line L18 is provided with a reheat steam stop valve 66. Further, a low-pressure steam supply line L20 for supplying the low-pressure steam LS generated in the low-pressure superheater 54 to the low-pressure steam transport line L19 is provided.

(4) The exhaust heat recovery boiler 12 is provided with an ammonia addition device 77 for adding ammonia as a pH adjuster to feed water in order to suppress corrosion of piping in a water supply system. The ammonia adding device 77 increases the pH of the feed water W by adding ammonia to the feed water W downstream of the condensate pump 36 and upstream of the ground condenser 37 in the feed water line L11. The pH adjuster is not limited to ammonia, and may be any amine containing at least one of hydrazine, monoethanolamine, and morpholine.

Therefore, during operation of the combined cycle plant 10, the compressor 21 compresses the air A in the gas turbine 11, and the combustor 22 mixes the supplied compressed air AC and the fuel gas F and burns. The turbine 23 is driven to rotate by the combustion gas FG supplied from the combustor 22. Further, the exhaust gas EX discharged from the gas turbine 11 (turbine 23) is sent to the exhaust heat recovery boiler 12, which generates steam S, and the steam S is sent to the steam turbine 13. The high-pressure turbine 31, the intermediate-pressure turbine 32, and the low-pressure turbine 33 are driven to rotate by the steam S. Then, the power generator 14 disposed coaxially with the gas turbine 11 and the steam turbine 13 generates power. On the other hand, the steam S used in the steam turbine 13 is cooled by the condenser 35 to be condensed, and is returned to the exhaust heat recovery boiler 12 as the feedwater W.

By the way, since the condenser 35 cools the steam S by the seawater SW to make a condensate (water supply W), a number of cooling water pipes constituting the cooling water line L7 are arranged inside. If the cooling water pipe is damaged for some reason, seawater flowing through the cooling water pipe mixes with the condensate of the condenser 35. Then, seawater components may be mixed into the water supply system of the exhaust heat recovery boiler 12, causing a trouble event such as heat transfer inhibition or corrosion. Therefore, it is necessary to detect the leakage of seawater in the condenser 35 and take measures against it.

Therefore, a plurality of acid conductivity measuring devices 81, 82, 83, 84, 85, 86, 87, and 88 are provided in the water supply system from the condenser 35 to the waste heat recovery boiler 12. The acid electric conductivity measuring device 81 is provided downstream of the condensing pump 36 and the ammonia adding device 77 in the water supply line L11 and upstream of the ground condenser 37. The acid conductivity measuring device 82 is provided downstream of the ground condenser 37 and upstream of the feedwater preheater 38. The acid conductivity measuring device 83 is provided on the low-pressure drum 52 of the low-pressure unit 41, and the acid conductivity measuring device 84 is provided on the low-pressure steam supply line L20. The acid conductivity measuring device 85 is provided on the medium pressure drum 62 of the medium pressure unit 42, and the acid conductivity measuring device 86 is provided on the medium pressure steam supply line L18. The acid conductivity measuring device 87 is provided on the high-pressure drum 72 of the high-pressure unit 43, and the acid conductivity measuring device 88 is provided on the high-pressure steam supply line L15. The position at which the acid conductivity measuring device is provided is not limited to the position described above.

Hereinafter, the acid conductivity measuring devices 81, 82, 83, 84, 85, 86, 87, and 88 will be described, but the acid conductivity measuring devices 81, 82, 83, 84, 85, 86, and 87. , 88 have substantially the same configuration, and thus only the acid conductivity measuring device 81 will be described in detail. FIG. 2 is a schematic diagram showing a device for measuring acid conductivity, and FIG. 3 is a schematic diagram showing a device for removing a measurement interfering substance in the device for measuring acid conductivity.

As shown in FIG. 2, the acid conductivity measuring device 81 includes a measurement interfering substance removing device 101, a cation exchanging device 102 as a cation removing device, and a first acid conductivity meter 103.

(4) The measurement interfering substance removing apparatus 101 is to vaporize and separate and remove the measuring interfering substance by heating and boiling the feed water W. The cation exchange device 102 removes cations from the feed water W from which the measurement interfering substance has been removed by the measurement interfering substance removing apparatus 101. The first acid conductivity meter 103 measures the acid conductivity of the feed water from which the interfering substances and cations have been removed.

The feed water W contains hydrogen ions (H ⁺ ) and hydroxide ions (OH ⁻ ) due to ionization of water. Further, the water supply W is brought in with carbon dioxide (CO ₂ ) due to the vacuum breaking of the condenser 35 and the makeup water to the water supply system, and is dissolved as bicarbonate ions (HCO ₃ ⁻ ). Further, the feed water W is mixed with ammonia (NH ₃ ) added by the ammonia adding device 77 for suppressing corrosion of the piping in the feed water system, and is dissolved as ammonium ions (NH ₄ ⁺ ). If the piping in the water supply system is broken, seawater is mixed into the water supply W, and the water supply W is mixed with sodium ions (Na ⁺ ) and chlorine ions (Cl ⁻ ).

Therefore, in order for the first acid electric conductivity meter 103 to measure the acid electric conductivity of the feed water with high accuracy, the measurement interfering substance removing device 101 heats the feed water W to bring it to a boil. Carbon dioxide (CO ₂ ) and ammonia (NH ₃ ), which are measurement interfering substances, are vaporized and separated. Then, the cation exchange device 102 removes sodium ions (Na ⁺ ) as cations from the feed water W. In the present embodiment, sodium (Na ⁺ ) is removed after removing carbon dioxide (CO ₂ ) and ammonia ions (NH ₄ ⁺ ) from the feed water W.

お よ び As shown in FIGS. 2 and 3, the measurement interfering substance removing apparatus 101 has a container 111 and an electric heater 112. The container 111 has a water supply W supply unit 113 on the lower side, a water supply discharge unit 114 on the upper side, and a measurement interfering substance discharge unit 115 on the upper ceiling. In the container 111, a water supply branch line L21 branched from the water supply line L11 is connected to the supply unit 113, and a water supply pump 116 is provided in the water supply branch line L21. Therefore, when the water supply pump 116 is driven, the water supply W of the water supply line L11 flows to the water supply branch line L21, and a predetermined amount of water supply W is supplied from the supply unit 113 into the container 111. In the container 111, one end of the first feedwater discharge line L22 is connected to the feedwater discharge section 114, and one end of the measurement interferent substance discharge line L23 is connected to the measurement interferent substance discharge section 115. The other end of L23 is open to the outside of the building.

The heater 112 heats the water supply W supplied into the container 111. The container 111 is provided with a temperature measuring device 117 for measuring the temperature of the feed water W heated by the heater 112. Further, a temperature control device 118 is connected to the heater 112, and the temperature control device 118 controls the heating temperature of the feed water W by the heater 112 based on the temperature of the feed water W measured by the temperature measuring device 117.

Therefore, a predetermined amount of feedwater W is supplied from the feedwater branch line L21 to the container 111 of the measurement interfering substance removing device 101, and when the feedwater W is heated and boiled by the heater 112, the oxygen dissolved in the feedwater W evaporates and becomes gaseous. It becomes bubbles of (water vapor) and rises toward the liquid level of the feed water W. At this time, the bicarbonate ions dissolved in the feed water W evaporate to carbon dioxide, and the ammonium ions dissolved in the feed water W evaporate to ammonia. Then, the vaporized carbon dioxide and ammonia rise toward the liquid surface of the feedwater W together with the gas bubbles. Then, a part of the carbon dioxide and the ammonia and the feed water W is turned into a gas and discharged from the measurement interfering substance discharge unit 115 through the measurement interfering substance discharge line L23. On the other hand, the feed water W from which carbon dioxide and ammonia have been removed contains only hydrogen ions, hydroxide ions, sodium ions, and chloride ions, and overflows from the feed water discharge unit 114 in the liquid state to discharge the first feed water. It is discharged to the line L22. At this time, the temperature control device 118 controls the heating temperature of the heater 112 such that the feedwater W boils and carbon dioxide and ammonia evaporate.

The cation exchange device 102 is configured by filling a column with a cation exchange resin, a supply unit 121 is provided at a lower part, and a discharge unit 122 is provided at an upper part. In the cation exchange device 102, the supply unit 121 is connected to the other end of the first feedwater discharge line L22, and the discharge unit 122 is connected to one end of the second feedwater discharge line L24. Therefore, when a predetermined amount of feedwater W is supplied from the first feedwater discharge line L22 to the cation exchange device 102, when the feedwater W passes through the cation exchange device 102, sodium ions are converted into hydrogen ions by the cation exchange resin. And discharged to the second feedwater discharge line L24. That is, the cation exchange resin adsorbs sodium ions and releases hydrogen ions. Since the hydrogen ion has a higher ultimate molar conductivity than the sodium ion, the detection sensitivity of chlorine by the first acid conductivity meter 103 is amplified. The feedwater W discharged to the second feedwater discharge line L24 contains only hydrogen ions, hydroxide ions, and chlorine. However, if the piping in the water supply system is not broken, seawater will not be mixed into the water supply W, sodium and chlorine will not be contained in the water supply W, and the cation exchange resin of the cation exchange device 102 will prevent measurement interference substances such as sodium. There is no adsorption.

酸 Further, the acid conductivity measuring device 81 is provided with a cooling device 131 for cooling the feed water W discharged from the measurement interfering substance removing device 101. The cooling device 131 is a heat exchanger that performs heat exchange between the feed water W supplied to the measurement interfering substance removing device 101 and the feed water W discharged from the measuring interfering substance removing device 101. That is, the feedwater W flowing through the first feedwater discharge line L22 is cooled by the feedwater W flowing through the feedwater branch line L21.

The acid electric conductivity measuring device 81 is provided with a second acid electric conductivity meter 141 for measuring the acid electric conductivity of the feed water W discharged from the measurement interfering substance removing device 101. The acid conductivity measuring device 81 is provided with an electric conductivity meter 142 for measuring the electric conductivity of the feed water W before being supplied to the measurement interfering substance removing device 101.

Here, a method for measuring the acid electric conductivity by the acid electric conductivity measuring device 81 will be described. The measuring method of the acid electric conductivity is to remove the cations from the heated and boiled feed water W by heating and boiling the feed water W to evaporate and remove the measurement interferents contained in the feed water. The method includes a cation removing step and an acid electric conductivity measuring step of measuring an acid electric conductivity of the feed water W from which the cation has been removed.

As shown in FIG. 1, during operation of the combined cycle plant 10, the steam S used in the steam turbine 13 is cooled by the condenser 35 to become condensed water, and is returned to the exhaust heat recovery boiler 12 as feedwater W. The ammonia adding device 77 adds ammonia to the feed water W flowing through the feed water line L11. At this time, the pH value of the feed water W after the addition of ammonia is measured, and the ammonia adding device 77 is controlled so that the pH value of the feed water W falls within a preset pH range (for example, from pH 9.4 to pH 10.0). Is preferred. At this time, the acid electric conductivity measuring devices 81 and 82 measure the acid electric conductivity of the feed water W in the water supply line L11, and the acid electric conductivity measuring devices 83, 85 and 87 are connected to the drums 52 and 82, respectively. The acid conductivity of the drum water W1, W2, W3 of 62, 72 is measured, and the measuring device 84, 86, 88 of the acid conductivity conducts each steam HS, MS, of each steam supply line L15, L18, L20. The acid conductivity of the LS is measured.

That is, in the acid conductivity measuring device 81, as shown in FIGS. 2 and 3, a predetermined amount of feed water W is supplied to the container 111, and the feed water W is heated by the heater 112 and boiled. The bicarbonate ions vaporized become carbon dioxide, and the ammonium ions dissolved in the feed water W vaporize to become ammonia. Then, the vaporized carbon dioxide and ammonia are converted into gas and discharged from the measurement interfering substance discharge unit 115 to the measurement interfering substance discharge line L23. On the other hand, the feedwater W from which the carbon dioxide and the ammonia have been removed overflows the feedwater discharge section 114 in a liquid state and is discharged to the first feedwater discharge line L22. The feedwater W flowing through the first feedwater discharge line L22 is cooled by the cooling device 131 and then supplied to the cation exchange device 102. Then, when the feedwater W passes through the cation exchange device 102, sodium ions are adsorbed and removed and discharged to the second feedwater discharge line L24. The feedwater W discharged to the second feedwater discharge line L24 contains hydrogen ions, hydroxide ions, and chlorine ions. If the seawater does not leak into the feedwater W, the cation exchange device 102 does not adsorb anything, and the discharged feedwater W contains only hydrogen ions and hydroxide ions.

At this time, the electric conductivity meter 142 measures the electric conductivity of the feed water W before being supplied to the measurement interfering substance removing device 101, and the second acid electric conductivity meter 141 discharges the water from the measuring interfering substance removing device 101. The acid electric conductivity of the supplied water W is measured. The first acid conductivity meter 103 measures the acid conductivity of the feed water from which carbon dioxide, ammonia, and sodium ions have been removed. Then, based on the acid conductivity of the feed water measured by the first acid conductivity meter 103, the chlorine ion concentration of the feed water W is calculated to determine the detection of seawater leakage. That is, when the chlorine ion concentration of the feedwater W exceeds a preset limit value, it is determined that the seawater has leaked to the feedwater W.

The configuration of the measurement interfering substance removing device 101 is not limited to the configuration described above. FIG. 4 is a schematic diagram illustrating a modification of the measurement interfering substance removing device in the acid conductivity measuring device.

(4) As shown in FIG. 4, the measurement interfering substance removing apparatus 101 is for separating and removing the measuring interfering substance by heating and boiling the feed water W to vaporize the measuring interfering substance. The measurement interfering substance removing device 101 has a container 111 and a heater 112. In the container 111, a water supply branch line L 21 is connected to a lower supply part 113, a first water supply discharge line L 22 is connected to an upper water supply discharge part 114, and a measurement interference substance discharge line L 23 is connected to a measurement interference substance discharge part 115. Is done. The heater 112 is provided in the container 111 and heats the water supply W supplied therein.

The measurement interfering substance removing device 101 is provided with an inert gas supply device 151 for supplying an inert gas (for example, nitrogen) to the water supply W in the container 111. In the inert gas supply line L31, an inert gas supply unit 152 is provided at the base end, a pump 153 is provided in the middle, a tip enters the lower part of the container 111, and a plurality of nozzles 154 are provided. Can be

In addition, in the measurement interfering substance removing device 101, a pressure reducing device 155 is connected to the measuring interfering substance discharge unit 115. The decompression device 155 is a decompression pump or a vacuum pump, and applies a negative pressure to the measurement interfering substance discharge line L23 connected to the measurement interfering substance discharge unit 115.

Therefore, when the feed water W in the container 111 is heated and boiled by the heater 112, the oxygen dissolved in the feed water W is vaporized to form gas bubbles and rise toward the liquid level of the feed water W. At this time, the bicarbonate ions dissolved in the feed water W evaporate to carbon dioxide, and the ammonium ions dissolved in the feed water W evaporate to ammonia. Then, the vaporized carbon dioxide and ammonia rise toward the liquid surface of the feedwater W together with the gas bubbles. Further, when the inert gas is supplied from the plurality of nozzles 154 to the water supply W in the container 111 by the inert gas supply device 151, the bubbles of the inert gas rise toward the liquid surface of the water supply W. Then, the vaporized carbon dioxide and ammonia are taken into the bubbles of the inert gas and rise toward the liquid surface of the feed water W.

(4) Then, carbon dioxide, ammonia, the inert gas, and part of the feed water W are gasified and discharged from the measurement interfering substance discharge unit 115 through the measurement interfering substance discharge line L23. At this time, a negative pressure acts on the measurement interfering substance discharge unit 115 from the measurement interfering substance discharge line L23 by the pressure reducing device 155, so that the carbon dioxide, ammonia, and inert gas vaporized in the container 111 are converted into the measurement interfering substance discharge line L23 It is easier to be discharged. On the other hand, the feedwater W from which carbon dioxide and ammonia have been removed overflows from the feedwater discharge unit 114 as it is, and is discharged to the first feedwater discharge line L22.

As described above, in the acid conductivity measuring device of the present embodiment, the measurement interfering substance removing device 101 that vaporizes and removes the measuring interfering substance contained in the feed water W by heating and boiling the feed water W is provided. A cation exchange device (cation removal device) 102 for removing cations from the feed water W from which the measurement interference material has been removed by the measurement interference material removal device 101, and a feed water W from which the cations have been removed by the cation exchange device 102 And a first acid conductivity meter 103 for measuring the acid conductivity of the sample.

Accordingly, the feed water W is heated and boiled by the measurement interference substance removing device 101, whereby measurement interference substances such as carbon dioxide and ammonia contained in the feed water W are vaporized and separated, and sodium ions are removed by the cation exchange device 102. It is removed and the first acid conductivity meter 103 measures the acid conductivity of the feed water W. Since the feedwater W from which carbon dioxide, ammonia, sodium ions and the like are removed is supplied to the first acid conductivity meter 103, the acid conductivity can be measured with high accuracy. Then, since the measurement interfering substance such as ammonia is vaporized and removed from the feed water W in advance, the cation exchange device 102 does not need to remove ammonia, and when there is no seawater leakage to the feed water W, the cation exchange There is almost no measurement interfering substance adhering to the device 102, the life of the cation exchange device 102 can be extended, and the size of the cation exchange device 102 can be reduced. As a result, an increase in cost can be suppressed by reducing the frequency of replacement of the cation exchange device 102, and the workability of the measurement operation of the acid electrical conductivity can be improved. In addition, since the first acid conductivity meter 103 measures the acid conductivity after removing ammonia or the like in advance, even if the pH value of the feed water W is higher than 10.0, even if the feed water system is used, the first Conductivity can be measured with high accuracy.

酸 In the acid conductivity measuring device of the present embodiment, a cooling device 131 for cooling the feed water W discharged from the measurement interfering substance removing device 101 is provided. Therefore, the cation exchange device 102 can appropriately remove the cations and can suppress damage to the cation exchange device 102.

In the acid conductivity measuring device of the present embodiment, the cooling device 131 exchanges heat between the feed water W supplied to the measurement interfering substance removing device 101 and the feed water W discharged from the measuring interfering substance removing device 101. Heat exchanger. Therefore, by using the feed water W supplied to the measurement interfering substance removing device 101 as a cooling medium, heat is recovered from the heated feed water W, and the feed water W supplied to the measuring interfering substance removing device 101 is heated. In addition, the heat can be effectively used, and the structure can be simplified by eliminating the need for another cooling medium.

In the acid conductivity measuring device of the present embodiment, the temperature measuring device 117 measures the temperature of the feed water W heated by the measurement interfering substance removing device 101, and the temperature of the feed water W measured by the temperature measuring device 117 is used. A temperature controller 118 for controlling the heating temperature of the feed water W by the measurement interfering substance removing device 101 is provided. Therefore, by controlling the heating temperature of the feed water W by the measurement interfering substance removing device 101 to an appropriate temperature, measurement interfering substances such as carbon dioxide and ammonia contained in the feed water W can be efficiently vaporized, and the feed water W An appropriate amount of feedwater W can be supplied to the cation exchange device 102 while suppressing vaporization of itself.

In the acid conductivity measuring device of the present embodiment, the measuring interfering substance removing device 101 includes a container 111 having a supply unit 113 provided at a lower part and discharge units 114 and 115 provided at an upper part, and a water supply W in the container 111. And an inert gas supply device 151 for supplying an inert gas to the water supply W in the container 111. Therefore, when the inert gas is supplied to the water supply W in the container 111 by the inert gas supply device 151, when the bubble of the inert gas rises in the water supply W, measurement of carbon dioxide, ammonia, and the like may be hindered. The substance is taken into the bubble of the inert gas and discharged, so that the measurement interfering substance contained in the feed water W can be efficiently separated and removed.

In the acid conductivity measuring device according to the present embodiment, the container 111 of the measurement interfering substance removing device 101 has a water supply discharging section 114 for discharging the water W by overflow and an evaporating measurement interfering substance discharged from the water W. The pressure reducing device 155 is connected to the measurement interfering substance discharge unit 115. Therefore, the feed water W heated in the container 111 and separated from the measurement interfering substances such as carbon dioxide and ammonia overflows the feed water discharge unit 114 and is discharged, while the carbon dioxide and ammonia separated from the feed water W are discharged. The measurement interfering substance gas is discharged from the measurement interfering substance discharge unit 115. At this time, by applying a negative pressure to the measurement interfering substance discharge unit 115 by the pressure reducing device 155, the gas of the measurement interfering substance separated in the container 111 is sucked into the measurement interfering substance discharge unit 115 and efficiently discharged. Can be.

In the acid conductivity measuring device of the present embodiment, a second acid conductivity meter 141 for measuring the acid conductivity of the feed water W discharged from the measurement interfering substance removing device 101 is provided. Therefore, the acid conductivity of the feed water W from which the measurement interfering substance has been removed can be measured with high accuracy by the second acid conductivity meter 141.

In the acid conductivity measuring device of the present embodiment, the electric conductivity meter 142 for measuring the electric conductivity of the feed water W before being supplied to the measurement interfering substance removing device 101 is provided. Therefore, since the electric conductivity meter 142 measures the electric conductivity of the feed water before being supplied to the measurement interfering substance removing device 101, the concentration of the pH adjuster such as ammonia can be measured. Further, by providing the electric conductivity meter 142 in the water supply branch line L21, the water supply flowing through the water supply line L11 and the acid electric conductivity measuring devices 81, 82, 83, 84, 85 can be measured by one electric conductivity meter 142. , 86, 87, 88 can be used to measure the concentration of a pH adjuster such as ammonia in the feed water.

Further, in the method for measuring the acid electric conductivity according to the present embodiment, there is provided a measurement interfering substance removing step of evaporating and removing a measuring interfering substance contained in the feed water W by heating and boiling the feed water W; The method includes a cation removal step of removing cations from the feedwater W from which the interfering substances have been removed, and an acid conductivity measurement step of measuring the acid conductivity of the feedwater W from which the cations have been removed.

Therefore, the feed water W from which carbon dioxide, ammonia, sodium, etc. have been removed is supplied to the first acid conductivity meter 103, so that the first acid conductivity meter 103 can accurately measure the acid conductivity. Can be measured. Then, since the measurement interfering substance such as ammonia is vaporized and removed from the feed water W in advance, the amount of the measurement interfering substance to be removed in the cation removing step is reduced, and the life of the apparatus can be extended. As a result, it is possible to suppress an increase in cost by reducing the replacement frequency of the device, and to improve the workability of the measurement operation of the acid electric conductivity.

Further, in the steam turbine plant of the present embodiment, the exhaust heat recovery boiler 12 that generates the steam S by the exhaust heat of the exhaust gas EG, and the steam turbine 13 that is driven by the steam S generated by the exhaust heat And a condenser 35 for returning the feed water W generated by cooling the steam S discharged from the steam turbine 13 by the seawater SW to the waste heat recovery boiler 12 and a feed water system of the feed water cooled by the condenser 35. And a measuring device 81, 82, 83, 84, 85, 86, 87, 88 for measuring acid conductivity.

Accordingly, the acid electric conductivity of the feed water W can be measured with high accuracy, and the number of measurement interfering substances adhering to the cation exchange resin constituting the cation exchange device 102 is reduced, and the life of the cation exchange device 102 is reduced. By extending the length and reducing the replacement frequency, it is possible to suppress an increase in cost, and to improve the workability of the work of measuring the acid electric conductivity.

In the above-described embodiment, the cation removing device 102 in which the column is filled with the cation exchange resin is used as the cation removing device, but the present invention is not limited to this configuration. For example, an electric cation exchanger may be used as the cation removing device.

Further, in the above-described embodiment, the electric heater 112 is applied to the measurement interfering substance removing device 101 that heats the feed water W to remove the interfering substance, but for example, the steam S or the exhaust gas generated in the combined cycle plant 10 EG or the like may be used.

Further, in the above-described embodiment, the exhaust heat recovery boiler 12 has the low-pressure unit 41, the medium-pressure unit 42, the high-pressure unit 43, and the reheater 44, but may include only the low-pressure unit 41 and the high-pressure unit 43. Further, only one unit may be used.

10. Combined cycle plant (steam turbine plant)
DESCRIPTION OF SYMBOLS 11 Gas turbine 12 Exhaust heat recovery boiler 13 Steam turbine 14 Generator 21 Compressor 22 Combustor 23 Turbine 24 Rotor (rotary shaft)
31 high-pressure turbine 32 medium-pressure turbine 33 low-pressure turbine 35 condenser 36 condensate pump 37 ground condenser 38 feedwater preheater 39 deaerator 41 low-pressure unit 42 medium-pressure unit 43 high-pressure unit 44 reheater 51 low-pressure economizer 52 low-pressure Drum 53 Low pressure evaporator 54 Low pressure superheater 61 Medium pressure economizer 62 Medium pressure drum 63 Medium pressure evaporator 64 Medium pressure superheater 71 High pressure economizer 72 High pressure drum 73 High pressure evaporator 74 High pressure superheater 77 Ammonia addition device 81 , 82, 83, 84, 85, 86, 87, 88 Acid Conductivity Measuring Device 101 Measurement Interfering Substance Removal Device 102 Cation Exchange Device 103 First Acid Conductivity Meter 111 Container 112 Heater 117 Temperature Measuring Device 118 Temperature Control device 131 Cooling device 141 Second acid conductivity meter 142 Electric conductivity meter 51 inert gas supply unit 155 decompressor A Air AC compressed air F fuel gas FG combustion gas EG exhaust W Water

Claims (10)

A measuring interference substance removing device that vaporizes and removes measurement interference substances contained in the feed water by heating and boiling the feed water,
A cation removal device that removes cations from the feedwater from which the measurement interfering substance has been removed by the measurement interfering substance removing apparatus,
A first acid conductivity meter for measuring the acid conductivity of feed water from which cations have been removed by the cation removal device;
An acid electric conductivity measuring device comprising: The apparatus for measuring acid conductivity according to claim 1, wherein a cooling device is provided for cooling the feedwater discharged from the measurement interfering substance removing device. 3. The cooling device according to claim 2, wherein the cooling device is a heat exchanger that performs heat exchange between feed water supplied to the measurement interfering substance removing device and feed water discharged from the measuring interfering substance removing device. An apparatus for measuring acid conductivity according to the above. A temperature measuring device for measuring the temperature of the feed water heated by the measurement interfering substance removing device, and a temperature control for controlling a heating temperature of the feed water by the measuring interfering substance removing device based on the temperature of the feed water measured by the temperature measuring device. The acid conductivity measuring device according to any one of claims 1 to 3, further comprising a device. The apparatus for removing a measurement interfering substance includes a container provided with a supply unit at a lower portion and a discharge unit provided at an upper portion, a heater for heating water supplied in the container, and a heater for supplying an inert gas to the water supplied in the container. The acid electric conductivity measuring device according to any one of claims 1 to 4, further comprising an active gas supply device. The measurement interfering substance removing device includes a container provided with a supply unit at a lower part and a discharge unit provided at an upper part, and a heater for heating water supply in the container, and the discharge part discharges the water supply by overflow. And a discharge device for discharging a measured interfering substance vaporized from the feed water, wherein a pressure reducing device is connected to the discharging unit. 6. The measuring device for acid electric conductivity according to any one of items 5 to 5. The acid according to any one of claims 1 to 6, further comprising a second acid conductivity meter for measuring the acid conductivity of the feedwater discharged from the measurement interfering substance removing device. Electric conductivity measuring device. The acid conductivity according to any one of claims 1 to 7, further comprising an electric conductivity meter for measuring the electric conductivity of the feed water before being supplied to the measurement interfering substance removing device. Rate measuring device. A measurement interfering substance removing step of vaporizing and removing a measuring interfering substance contained in the feed water by heating and boiling the feed water,
A cation removal step of removing cations from the heated boiling water;
An acid conductivity measuring step of measuring the acid conductivity of the feedwater from which the cations have been removed,
A method for measuring acid electrical conductivity, comprising: An exhaust heat recovery boiler that generates steam by exhaust heat of exhaust gas,
A steam turbine driven by steam generated by the exhaust heat recovery boiler,
A condenser that returns feedwater generated by cooling steam discharged from the steam turbine to the waste heat recovery boiler,
The acid conductivity measuring device according to any one of claims 1 to 8, which is provided in a water supply system cooled by the condenser.
A steam turbine plant comprising:

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