JP2007064856A - Sampling device, sampling method and thermoelectric power plant provided with sampling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sampling device for more rapidly analyzing the cleanness of sampling water in cooling of a turbine blade or the like by steam to certainly ensure the integrity of the turbine blade or the like. <P>SOLUTION: In the sampling device composed of a sample analyzing system equipped with supplying systems 37 and 38 for sampling and an analyzer for analyzing the properties of the sample supplied from sample analyzing systems 50-53, bypass systems 42 and 43 branched from the sampling system to divide a part of the sample are provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sampling device employed in a thermal power plant or the like, and in particular, when an abnormality sign is detected in a sample such as steam or water, an accurate water quality analysis can be performed more quickly. The present invention relates to a sampling device, a sampling method, and a power plant including the sampling device.

  Conventionally, in a thermal power plant, in order to prevent corrosion of the water-steam system equipment that composes the plant, ammonia or hydrazine is injected into the condensate / water supply system as a corrosion-preventing chemical to maintain the water quality at an appropriate value. It is carried out.

  For this water quality adjustment and water quality management, there is a sampling system that constantly samples water from the water-steam system and constantly analyzes and monitors conductivity, pH, dissolved oxygen, hydrazine, iron, silica, etc. As the configuration, there is one disclosed in Patent Document 1.

  As shown in FIG. 5, the sampling system disclosed in Patent Document 1 includes a first sampling system 1 and a second sampling system 2 arranged in parallel, and each of the sampling systems 1 and 2 is provided. A dummy water supply system 3 to be connected is provided.

In both the first sampling system 1 and the second sampling system 2, the coupling pipes 4a and 4b are connected to a mother pipe (not shown) as a supply source of water or steam, and these coupling pipes 4a and 4b. In order from the downstream side to the downstream side, sampling source valves 6a and 6b that open and close by the driving force of the electromagnetic valves 5a and 5b, and a cooler 7a that cools a sample such as high-temperature steam or water (hereinafter referred to as sampling water) to room temperature. 7b, decompressors 8a and 8b for depressurizing high-pressure sampling water to atmospheric pressure, stop valves 9a, 9b ₁ and 9b ₂ , flow meters 10a, 10b ₁ and 10b ₂ , constant temperature for maintaining the temperature of the sampling water at a constant value vessel 11, a thermometer _12a, 12b 1, 12b ₂ and analyzer _13a, with the 13b 1, 13b _2, conductivity at spectrometer _{13a, 13b 1, 13b 2,} PH, analysis of water, such as dissolved oxygen concentration, monitoring The line To have.

  The first sampling system 1 and the second sampling system 2 branch from the inlet side of the sampling valves 6a and 6b and are flushed through flushing valves 15a and 15b that are opened and closed by the driving force of the electromagnetic valves 14a and 14b. It is equipped with flushing systems 16a and 16b, and drain water accumulated during the plant operation stop is blown out of the system.

And the above-mentioned water supply system 3 connects the branch pipes 18a and 18b inserted with valves such as the electromagnetic valves 17a and 17b to the inlet sides of the stop valves 9a, 9b ₁ and 9b ₂ , respectively, thereby stopping the plant operation. When sampling water at the time cannot be collected, the dummy water is caused to flow into the analyzers 13a, 13b ₁ and 13b ₂ and the analyzer cell is immersed in the dummy water. As a result, the analyzer cell is maintained in an always operable state, and water quality can be analyzed at an early stage when the plant is restarted.
Japanese Examined Patent Publication No. 3-87058

  By the way, in recent thermal power plants, a combined cycle power plant in which an exhaust heat recovery boiler and a steam turbine plant are combined with a gas turbine plant is operated from the advantages of improving the plant thermal efficiency and shortening the startup time.

  In this combined cycle power plant, the combustion gas (working fluid) of the gas turbine plant is at a high temperature of, for example, 1300 ° C. or more. In order to cope with this high temperature, the turbine blades and the like are cooled. Yes.

  Cooling of turbine blades or the like is performed by so-called steam cooling in which a serpentine flow path is formed in a narrow, thin blade and steam having a high specific heat flows through the serpentine flow path. For this reason, if the water quality analysis and monitoring of the steam are not sufficiently performed, the flow path in the blade may be clogged, which may cause breakage or breakage.

  In consideration of such an event, steam water quality management has recently been strengthened.

  However, when the sampling system shown in FIG. 5 is applied to water quality management for steam cooling, it has several problems, one of which is faster supply of sampling water to the analyzer.

That is, the analyzers 13a, 13b ₁ and 13b ₂ provided in the conventional sampling system shown in FIG. 5 are structurally limited in flow rate and cannot handle a large amount of sampling water. The cleanliness analysis of the sampling water is delayed due to the time delay until the analyzers 13a, 13b ₁ and 13b ₂ are reached. For this reason, if the sample analysis value shows signs before the plant operation was restricted, detailed analysis could not be performed immediately, which had a significant impact on the maintenance of turbine blades that perform steam cooling. .

  In general, it is well known that the flow rate and the flow velocity are in a proportional relationship. For this reason, in order to analyze the cleanliness of the sampling water earlier, it is necessary to flow the sampling water at a higher flow rate.

However, as described above, the conventional analyzers 13a, 13b ₁ , 13b ₂ are limited by the excessive amount of the flow rate, and thus are not suitable for measurement objects for which quick response is required, and some new improvement has been demanded. .

  The present invention has been made on the basis of such circumstances, and when a sign of abnormality appears in the sampling water, a detailed analysis of the sampling water is performed earlier to ensure the soundness of the turbine blades and the like. It is an object of the present invention to provide a thermal power plant including a sampling device, a sampling method, and a sampling device.

  In order to achieve the above-mentioned object, the sampling apparatus according to the present invention, as described in claim 1, analyzes a sample supply system for collecting a sample and analyzes the properties of the sample supplied from the sampling system. A sample collection device comprising a sample analysis system equipped with a vessel is provided with a bypass system that branches from the sample collection system and diverts a part of the sample.

  Further, in order to achieve the above object, the sample analysis method according to the present invention flows a sample collected by the sample collection system to a sample analysis system provided downstream, as described in claim 5, and performs this sample analysis. In a sample analysis method in which a sample is analyzed by an analyzer provided in the system, when an abnormal sign of the sample is detected by the analyzer, a part of the sample is diverted from the sampling system to the bypass system, In this method, the flow rate of the sample is increased to flow through the analyzer, and the detailed analysis of the sample by the analyzer is performed at an early stage.

  According to the sampling apparatus and sampling method of the present invention, a bypass system is provided in the sampling system, the flow rate of the sampling water flowing therethrough is increased, the flow rate accompanying the increase in the sampling water flow rate is increased, Since a part of the sampling water is made to flow into the analyzer, when an abnormal value is observed in the properties of the sampling water, the analysis result is advanced and the measures are properly dealt with under the high-speed sampling water. You can quickly maintain the health of your.

  An embodiment of a sampling device according to the present invention will be described with reference to the drawings and reference numerals attached to the drawings.

  FIG. 1 is a schematic system diagram of a combined cycle power plant as an example of a plant to which a sampling apparatus according to the present invention is applied.

  The combined cycle power plant is a combination of a gas turbine plant 20 with an exhaust heat recovery boiler 21 and a steam turbine plant 22, and generates steam by using exhaust gas (exhaust heat) of the gas turbine plant 20 to generate steam. Is supplied to the steam turbine plant 22 to perform expansion work and to effectively use the exhaust gas.

  The gas turbine plant 20 includes a generator 23, an air compressor 24, a gas turbine combustor 25, and a gas turbine 26. The gas (atmosphere) sucked by the air compressor 24 is increased in pressure, and the high-pressure air is combusted with the fuel in the gas turbine. The combustion gas is generated, and the generated combustion gas is expanded by the gas turbine 26, and the generator 23 is driven by the power generated at that time. The exhaust heat recovery boiler 21 is supplied.

  The exhaust heat recovery boiler 21 includes a number of heat exchangers such as a superheater and an evaporator. The exhaust gas from the gas turbine plant 20 is used as a heat source, and heat is supplied to the feed water supplied from the steam turbine plant 22 to generate steam. The generated steam is supplied to the steam turbine plant 22 via the main steam pipe 27.

  The steam turbine plant 22 includes a steam turbine 28, a generator 29, a condenser 30, and an auxiliary steam system 31, and expands to steam supplied from the exhaust heat recovery boiler 21 to the steam turbine 28 via the main steam pipe 27. The generator 29 is driven by the power generated during the work, and the turbine exhaust that has finished the expansion work is supplied to the condenser 30, where it is condensed to condensate, and this condensate is used as feed water. The exhaust heat recovery boiler 21 is returned.

  Further, the auxiliary steam system 31 includes a moisture separator 35 in the auxiliary steam pipe 34 having one end connected to the main steam pipe 27 and the other end connected to the in-house boiler 33, and from the exhaust heat recovery boiler 21 at startup. When the temperature and pressure of the steam do not reach predetermined values, moisture is removed from the saturated steam supplied from the in-house boiler 33 by the moisture separator 35, and then the auxiliary steam pipe 34 and the main steam pipe 27 are connected. To the steam turbine 28.

  In the combined cycle power plant having such a configuration, for example, the main steam pipe 27 on the inlet side of the steam turbine 28 is provided with a sampling device 36 according to the present invention.

  As shown in FIG. 2, the sampling device 36 includes a first sampling system 37 and a second sampling system 38 arranged in parallel, and a water supply system 39 connected to each of the sampling systems 37 and 38. In addition, a first flushing system 40 and a second flushing system 41 branched from the respective sampling systems 37 and 38, and a first bypass system 42 and a second bypass system 43 are provided.

In both the first sampling system 37 and the second sampling system 38, the coupling pipes 44a and 44b are connected to the main steam pipe 27, which is a supply source of steam, and the downstream of the coupling pipes 44a and 44b. The sampling water main valves 46a and 46b that are opened and closed by the driving force of the electromagnetic valves 45a and 45b, the coolers 47a and 47b that cool the high-temperature sampling water to room temperature, and the decompressors that depressurize the high-pressure sampling water to atmospheric pressure. 48a, 48b, stop valves 49a, 49b ₁ , 49b ₂ , flow meters 50a, 50b ₁ , 50b ₂ , a thermostat 51 for maintaining the temperature of the sampling water at a constant value, thermometers 52a, 52b ₁ , 52b _2, and an analyzer _53a, includes a 53b 1, 53b _2, analyzer _53a, conductivity at 53b 1, 53b _2, PH, analysis of water, such as dissolved oxygen concentration, are monitoring

And the above-mentioned water supply system 39 connects the branch pipes 67a and 57b inserted with valves such as the electromagnetic valves 56a and 56b to the inlet sides of the stop valves 49a, 49b ₁ and 49b ₂ , respectively, thereby stopping the plant operation. When sampling water cannot be collected, the dummy water is caused to flow into the analyzers 53a, 53b ₁ and 53b ₂ and the analyzer cell is immersed in the dummy water. As a result, the analyzer cell is maintained in an always operable state, and water quality can be analyzed at an early stage when the plant is restarted.

  The first sample collection system 37 and the second sample collection system 38 branch from the inlet side of the sampling water main valves 46a and 46b, and are passed through flushing valves 55a and 55b that are opened and closed by the driving force of the electromagnetic valves 58a and 58b. A first flushing system 40 and a second flushing system 41 are provided, and drain water accumulated during the plant operation stop is discharged out of the system.

  In the sample collection device 36 having such a configuration, the present embodiment is configured so that the sampling water main valve 46a of the first sample collection system 37 and the sampling water main valve 46b of the second sample collection system 38 are respectively input from the inlet side. Each of the first bypass system 42 and the second bypass system 43 that branch off is provided.

  Each of the first bypass system 42 and the second bypass system 43 is provided with air driven valves 59a and 59b and electromagnetic valves 60a and 60b for driving the air driven valves 59a and 59b to open and close.

  The air-driven valves 59a and 59b are provided in the first bypass system 42 and the second bypass system 43, respectively, so that a relatively large caliber can be manufactured. This is so that it can flow.

In the sampling device 36 having such a configuration, in the present embodiment, the air-driven valves of the first bypass system 42 and the second bypass system 43 are used when there is no sign of abnormality in the sample analysis value of the sampling water. 59a and 59b are closed, and using the sampling water collected from the first sample collection system 37 and the second sample collection system 38 or the sampling water supply systems 57a and 57b, the analyzer 53a, 53b ₁ and 53b ₂ analyze the properties. I do.

On the other hand, in the sample analysis, for example, when silica or the like is detected and there are signs of abnormality, that is, signs before the plant operation is restricted, it is necessary to analyze the sampling water in more detail. In the present embodiment, the air driven valves 59a and 59b provided in the first bypass system 42 and the second bypass system 43 are opened by the driving force of the electromagnetic valves 60a and 60b, and the first sampling system 37 and the second sampling system 37 Part of the sampling water collected by each of the sample collection systems 38 flows to the first bypass system 42 and the second bypass system 43, and the rest flows to the analyzers 53a, 53b ₁ , 53b ₂ .

At this time, since the air driven valves 59a and 59b provided in the first bypass system 42 and the second bypass system 43 have a large diameter, the flow rate increases, and the flow velocity also increases based on the increased flow rate. Get faster. This increase in flow velocity also affects the sampling water flowing in each of the first sampling system 37 and the second sampling system 38, and makes the flow to each of the analyzers 53a, 53b ₁ , 53b ₂ faster. As a result, the detailed properties of the sampling water can be analyzed more quickly.

It should be noted that the air drive valves 59a and 59b of the first bypass system 42 and the second bypass system 43 are respectively connected to the analyzers 53a, 53b ₁ and 53b _{2 of} the first sampling system 37 and the second sampling system 38. The aperture is set so that the desired sampling water flow rate is obtained. In other words, the sampling water accelerates the flow velocity of each of the first bypass system 42 and the second bypass system 43, and a part of the sampling water with the accelerated flow velocity is supplied to each of the first sampling system 37 and the second sampling system 38. Are supplied to the analyzers 53a, 53b ₁ and 53b ₂ to accelerate sample analysis.

  On the other hand, as shown in FIG. 3, of the sampling water supplied to the sampling device 36 from the mother pipes 61a and 61b, which are water or steam supply sources, the first sampling system 37 and the second sampling system 38 The sampling water supplied to each is discharged into the drain pit 62 after analyzing its properties.

  Further, the sampling water supplied to each of the first flushing system 40 and the second flushing system 41 is discharged to the recovery pit 63 and is reused as, for example, water supply from here.

  In addition, the sampling water supplied to each of the first bypass system 42 and the second bypass system 43 removes moisture by the moisture separator 35, and then steam that breaks the auxiliary steam pipe 34 together with the steam from the in-house boiler. The turbine is supplied and reused.

  The sampling water supplied to each of the first bypass system 42 and the second bypass system 43 may be collected by the condenser 32 as shown in FIG.

Thus, in the present embodiment, the first bypass system 42 and the second bypass system 43 are provided in each of the first sampling system 37 and the second sampling system 38 of the sampling apparatus 36, and the bypass systems 42, 43 are provided. Are provided with large-diameter air-driven valves 59a and 59b, the flow rate of the sampling water flowing therethrough is increased, the flow rate associated with the increase in the flow rate of the sampling water is increased, and a part of the sampling water having a faster flow rate is first. Since the analyzer 53a, 53b ₁ , 53b ₂ is provided in each of the sample collection system 37 and the second sample collection system 38, when an abnormal sign is detected in the properties of the sampling water, the analyzer 53a, it is possible to quickly flow rate of sampling water flowing in 53b _1, 53b _2, analysis can provide a faster, is addressed quickly by the management of the health of the plant this Can.

1 is a schematic system diagram showing a combined cycle power plant to which a sampling apparatus according to the present invention is applied. 1 is a schematic system diagram showing a sampling device according to the present invention. 1 is a schematic system diagram showing a first embodiment of a sampling water discharge system in a sampling device according to the present invention. FIG. The schematic system diagram which shows 2nd Embodiment of the discharge system of the sampling water in the sampling device which concerns on this invention. The schematic system diagram which shows the conventional sample-collecting apparatus.

Explanation of symbols

1 first sampling system 2 second sampling system 3 water supply system 4a, 4b Togokan 5a, 5b solenoid valves 6a, 6b sampling for main valve 7a, 7b condenser 8a, 8b decompressor 9a, _9b 1, 9b ₂ stop valves 10a, 10b ₁ , 10b ₂ flow meters 11 thermostats 12a, 12b ₁ , 12b ₂ thermometers 13a, 13b ₁ , 13b ₂ analyzers 14a, 14b electromagnetic valves 15a, 15b flushing valves 16a, 16b flushing system 17a , 17b Solenoid valves 18a, 18b Dummy water supply system 20 Gas turbine plant 21 Waste heat recovery boiler 22 Steam turbine plant 23 Generator 24 Air compressor 25 Gas turbine combustor 26 Gas turbine 27 Main steam pipe 28 Steam turbine 29 Generator 30 Condenser 31 Auxiliary steam system 33 In-house boiler 34 Auxiliary steam pipe 35 Moisture separator 36 Sampling device 37 First sampling system 38 Second sampling system 39 Water supply system 40 First flushing system 41 Second flushing system 42 First bypass system 43 Second bypass systems 44a, 44b Joint pipes 45a, 45b Electromagnetic valves 46a, 46b Sample harvesting stop valve 47a, 47b condenser 48a, 48b pressure reducer _49a, 49b _1, 49b ₂ stop valves _50a, 50b _1, 50b ₂ flow meter 51 incubator _52a, 52b _1, 52b ₂ thermometers _53a, 53b _1, 53b ₂ analyzers 54a and 54b Electromagnetic valves 55a and 55b Flushing valves 56a and 56b Electromagnetic valves 57a and 57b Branch pipes 58a and 58b Electromagnetic valves 59a and 59b Air-driven valves 60a and 60b Electromagnetic valves 61a and 61b Main pipe 62 Drain pit 63 Recovery pit

Claims (6)

In a sample collection device comprising a sample supply system for collecting a sample and a sample analysis system equipped with an analyzer for analyzing the properties of the sample supplied from the sample collection system,
A sampling apparatus comprising a bypass system that branches off from the sampling system and diverts a part of the sample. 2. The sampling apparatus according to claim 1, wherein the bypass system includes a stop valve that closes during normal operation and opens when an abnormality sign is detected in the sample analysis value. 2. The sampling apparatus according to claim 1, wherein the bypass system is configured to collect the sample by a moisture separator provided in the sample auxiliary steam system. 2. The sampling apparatus according to claim 1, wherein the bypass system is configured to collect a sample in a condenser provided in the steam turbine plant. In a sample analysis method in which a sample collected by a sample collection system is flowed to a sample analysis system provided downstream, and the sample is analyzed by an analyzer provided in the sample analysis system.
When an abnormal sign of the sample is detected by the analyzer, a part of the sample is diverted from the sampling system to the bypass system so that the flow rate of the sample is increased to flow to the analyzer. A sample analysis method characterized by conducting detailed analysis at an early stage. A thermal power plant comprising the sampling device according to any one of claims 1 to 4.

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