US20150377078A1 - Boiler operation method and boiler - Google Patents

Boiler operation method and boiler Download PDF

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Publication number
US20150377078A1
US20150377078A1 US14/767,724 US201414767724A US2015377078A1 US 20150377078 A1 US20150377078 A1 US 20150377078A1 US 201414767724 A US201414767724 A US 201414767724A US 2015377078 A1 US2015377078 A1 US 2015377078A1
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United States
Prior art keywords
boiler
preservation
water
supply system
range
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US14/767,724
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English (en)
Inventor
Toshihisa ANAI
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Mitsubishi Power Ltd
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Mitsubishi Hitachi Power Systems Ltd
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Assigned to MITSUBISHI HITACHI POWER SYSTEMS, LTD. reassignment MITSUBISHI HITACHI POWER SYSTEMS, LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ANAI, Toshihisa
Publication of US20150377078A1 publication Critical patent/US20150377078A1/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B1/00—Methods of steam generation characterised by form of heating method
    • F22B1/02—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers
    • F22B1/18—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being a hot gas, e.g. waste gas such as exhaust gas of internal-combustion engines
    • F22B1/1807—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being a hot gas, e.g. waste gas such as exhaust gas of internal-combustion engines using the exhaust gases of combustion engines
    • F22B1/1815—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being a hot gas, e.g. waste gas such as exhaust gas of internal-combustion engines using the exhaust gases of combustion engines using the exhaust gases of gas-turbines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K25/00—Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for
    • F01K25/06—Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for using mixtures of different fluids
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K23/00—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids
    • F01K23/02—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled
    • F01K23/06—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle
    • F01K23/10—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle with exhaust fluid of one cycle heating the fluid in another cycle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B35/00—Control systems for steam boilers
    • F22B35/007—Control systems for waste heat boilers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22D—PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER FOR STEAM GENERATION; FEED-WATER SUPPLY FOR STEAM GENERATION; CONTROLLING WATER LEVEL FOR STEAM GENERATION; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN STEAM BOILERS
    • F22D1/00—Feed-water heaters, i.e. economisers or like preheaters
    • F22D1/16—Feed-water heaters, i.e. economisers or like preheaters with water tubes arranged otherwise than in the boiler furnace, fire tubes, or flue ways
    • F22D1/18—Feed-water heaters, i.e. economisers or like preheaters with water tubes arranged otherwise than in the boiler furnace, fire tubes, or flue ways and heated indirectly
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E20/00—Combustion technologies with mitigation potential
    • Y02E20/16—Combined cycle power plant [CCPP], or combined cycle gas turbine [CCGT]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E20/00—Combustion technologies with mitigation potential
    • Y02E20/16—Combined cycle power plant [CCPP], or combined cycle gas turbine [CCGT]
    • Y02E20/18—Integrated gasification combined cycle [IGCC], e.g. combined with carbon capture and storage [CCS]

Definitions

  • the present invention relates to a boiler operation method and a boiler, and more particularly relates to a boiler operation method and a boiler used when preserving a water supply system through which boiler water is circulated.
  • Boiler and steam turbine power plant, gas turbine and (heat recovery steam generator) steam turbine combined cycle power plant, and the like have water supply systems through which boiler water is circulated for generating steam (water vapor), but integrated coal gasification combined cycle (IGCC) power plants have many water supply systems for generating steam.
  • An integrated coal gasification combined cycle power plant includes a gasifier, a gas cooler, a gas turbine section, a heat recovery steam generator, a steam turbine section, and a generator.
  • the gasifier generates combustible raw syngas from the gasification of pulverized coal.
  • the gas cooler cools the raw syngas.
  • the gas turbine section generates high temperature high pressure combustion gas by combustion of the cooled raw syngas, thereby generating rotational power.
  • the heat recovery steam generator recovers thermal energy from the exhaust gas from the gas turbine section, to generate high pressure steam.
  • the steam turbine section generates rotational power using the steam.
  • the generator converts the rotational power generated by the gas turbine section and the steam turbine section into electrical power
  • the gas cooler and the heat recovery steam generator include water supply systems through which boiler water is circulated.
  • the gas cooler cools the raw syngas generated by the gasifier and the heat recovery steam generator cools the exhaust gas discharged from the gas turbine section by circulating boiler water through the water supply systems.
  • the gas cooler and the heat recovery steam generator heat the boiler water and generate steam supplied to the steam turbine section, by circulating the boiler water through the water supply systems.
  • the boiler water is discharged when it is necessary to change the piping or the like of the water supply system.
  • the boiler water is preserved without discharging it in order to rapidly restart the power plant, it is desirable to prevent corrosion of the metallic components such as the inside of the piping of the water supply systems and the like.
  • Patent Document 1 Japanese Unexamined Patent Application Publication No. 2004-323954A
  • Patent Document 2 Japanese Unexamined Patent Application Publication No. 2003-39084A
  • Patent Document 3 Japanese Unexamined Patent Application Publication No. H44-83592A
  • the occurrence of corrosion in the inside of piping and the like can be reduced by filling the water supply system with preserved water that contains hydrazine during the preservation period when operation of the power plant is stopped and the boiler water is not discharged while the equipment is being preserved to enable rapid restarting.
  • hydrazine has an adverse effect on health, so it is necessary to take care when handling it (see Patent Documents 1, 2, and 3). It is desirable that corrosion of the metal members of the water supply system be reduced more easily and over a longer period of time.
  • the boiler operation method is executed using a water supply system of a boiler.
  • the boiler includes the water supply system through which the boiler water to be heated flows, and ammonia addition equipment configured to add ammonia to the boiler water to adjust the pH of the boiler water.
  • the boiler operation method includes: measuring a pH of the boiler water; passing the boiler water through the water supply system when the pH is within an operational pH range so that the boiler water is heated upon operating the boiler; controlling the ammonia addition equipment so that ammonia is added to the boiler water until the pH is within a preservation pH range upon stopping the boiler; and stopping the flow of the boiler water in the water supply system when the pH is within the preservation pH range.
  • a discretionary pH within the preservation pH range is equal to or greater than a discretionary pH within the operational pH range.
  • this boiler operation method by filling the water supply system with boiler water having a pH within the preservation pH range, it is possible to reduce corrosion of the water supply system for a longer period of time during preservation of the equipment when the operation of the power plant has stopped compared with filling the water supply system with boiler water having a pH within the operational pH range.
  • ammonia can normally be handled more easily compared with hydrazine. Therefore, this boiler operation method can more easily prevent corrosion of the water supply system compared with filling the water supply system with preservation boiler water that contains hydrazine.
  • the boiler operation method further includes passing the boiler water through the water supply system when the pH is within the operational pH range so that the boiler water is heated, upon restarting operation of the boiler after the flow of the boiler water in the water supply system has been stopped.
  • the pH of the preservation boiler water is within the operational pH range, so it is possible to restart the boiler more easily and in a shorter period of time by using the preservation boiler water as it is as operation boiler water.
  • the boiler operation method further includes referring to a table of a plurality of preservation periods mapped to a plurality of preservation pH ranges, and introducing the preservation pH range corresponding to the period of time that a power plant is stopped and boiler water is not flowing through the water supply system, from among the plurality of preservation pH ranges.
  • a lower limit of a first preservation pH range corresponding to a first period from among the plurality of preservation pH ranges is greater than a lower limit of a second preservation pH range corresponding to a second period that is longer than the first period from among the plurality of preservation pH ranges.
  • the boiler according to a second aspect of the present invention includes: a water supply system through which boiler water to be heated flows; ammonia addition equipment configured to add ammonia to the boiler water; a pH measurement device configured to measure the pH of the boiler water; and a control device configured to control the ammonia addition equipment.
  • the control device includes a control circuit for normal operation configured to control the ammonia addition equipment so that the pH is within an operational pH range when the boiler water is flowing through the water supply system so that the boiler water is heated, and a control circuit for preservation period configured to control the ammonia addition equipment so that, upon stopping the boiler, the pH is within the preservation pH range before stopping the flow of the boiler water through the water supply system.
  • a discretionary pH within the preservation pH range is equal to or greater than a discretionary pH within the operational pH range.
  • this boiler it is possible to further reduce corrosion of the water supply system by filling the water supply system with boiler water having a pH within the preservation pH range compared with filling the water supply system with boiler water having a pH within the operational pH range.
  • ammonia can normally be handled more easily compared with hydrazine. Therefore, with this boiler, corrosion of the water supply system during equipment preservation can be more easily suppressed compared with filling the water supply system with preservation boiler water that contains hydrazine.
  • a gas cooler includes a flow path through which raw syngas generated by gasification of a carbonaceous solid fuel with an oxidant, and a flow path (boiler water circulation system) through which supply water flows. At this time, the water supply system heats the boiler water using the heat of the raw syngas.
  • This gas cooler can more easily suppress corrosion of the water supply system during equipment preservation when a power plant is stopped.
  • a heat recovery steam generator includes a flow path through which exhaust gas discharged from a gas turbine flows, and a flow path (boiler water circulation system) through which supply water flows.
  • the water supply system heats the boiler water using the heat of the exhaust gas.
  • This heat recovery steam generator can more easily prevent corrosion of the water supply system during equipment preservation when the power plant is stopped.
  • An integrated coal gasification combined cycle power plant includes: the heat recovery steam generator according to the present invention; a gasifier configured to generate raw syngas by gasification of a carbonaceous solid fuel; a gas turbine configured to discharge exhaust gas by generating power using the raw syngas; and a steam turbine configured to generate power using steam.
  • the steam is generated by the water supply system by heating the boiler water using the heat of the raw syngas and using the heat of the exhaust gas.
  • This integrated coal gasification combined cycle power plant can more easily suppress corrosion of the water supply system during equipment preservation when the power plant is stopped.
  • the boiler operation method and the boiler according to the present invention can easily reduce corrosion of the water supply system during equipment preservation by filling the water supply system with boiler water having a pH higher than the pH of the boiler water circulated during operation.
  • FIG. 1 is a schematic view illustrating the configuration of an integrated coal gasification combined cycle power plant.
  • FIG. 2 is a schematic view illustrating the configuration of a boiler water circulating system.
  • FIG. 3 is a block diagram illustrating a control device.
  • FIG. 4 is a flow illustrating a boiler preservation method of a comparative example.
  • FIG. 5 is a graph showing the relationship between pH and corrosion.
  • the integrated coal gasification combined cycle power plant 10 includes a gasifier 1 , a gas cooler 2 , a gas turbine 3 , a heat recovery steam generator 5 , a steam turbine 6 , a generator 7 , and a condenser 8 .
  • the gasifier 1 generates combustible high temperature raw syngas from pulverized coal obtained by pulverizing coal as carbonaceous solid fuel supplied from outside the power plant, and air (or oxygen) as an oxidant.
  • the gas cooler 2 generates cooled raw syngas from the high temperature raw syngas generated by the gasifier 1 .
  • the gas cooler 2 generates high temperature high pressure steam from the boiler water generated by the condenser 8 , by heat exchange when cooling the high temperature raw syngas.
  • the gas turbine 3 generates rotational power using the cooled raw syngas generated by the gas cooler 2 , and discharges high temperature exhaust gas.
  • the heat recovery steam generator 5 generates high temperature high pressure steam from the boiler water generated by the condenser 8 , by heat exchange when cooling the high temperature exhaust gas discharged from the gas turbine 3 .
  • the steam turbine 6 generates rotational power using the steam generated by the gas cooler 2 and the steam generated by the heat recovery steam generator 5 , and discharges exhaust steam.
  • the generator 7 generates electrical power using the rotational power generated by the gas turbine 3 and the rotational power generated by the steam turbine 6 .
  • the condenser 8 generates water from the exhaust steam discharged from the steam turbine 6 to produce boiler water.
  • FIG. 2 illustrates a water supply (circulation) system portion of the gas cooler 2 .
  • the gas cooler 2 includes a water supply (circulation) system 11 , ammonia addition equipment 12 , a pH measurement device 14 , and a control device 15 , and includes a raw syngas flow path a.
  • the raw syngas generated by the gasifier 1 flows through the raw syngas flow path a.
  • the water supply system 11 includes a steam drum 16 , a plurality of downcast pipes 17 , a header 18 , and a plurality of heat transfer pipes 19 .
  • the steam drum 16 is formed into a vessel formed from steel based material (hereinafter, referred to as “steel”).
  • the steam drum 16 is connected to the condenser 8 via a pipe line 30 so that boiler water generated in the condenser 8 is supplied to the inside of the steam drum 16 .
  • the steam drum 16 is connected to the steam turbine 6 via a pipe line 31 so that steam generated in the inside of the steam drum 16 is supplied to the steam turbine 6 .
  • the steam drum 16 is also connected to the plurality of downcast pipes 17 so that the boiler water accumulated in the inside of the steam drum 16 is supplied to the plurality of downcast pipes 17 .
  • Each of the plurality of downcast pipes 17 is formed from steel and is formed as a flow path through which boiler water supplied from the steam drum 16 flows.
  • Each of the plurality of downcast pipes 17 is connected to the header 18 so that the boiler water is supplied to the header 18 .
  • the header 18 is formed from steel and is formed as a header into which the boiler water supplied from the plurality of downcast pipes 17 merge.
  • the header 18 is connected to the plurality of heat transfer pipes 19 so that the boiler water is supplied to the plurality of heat transfer pipes 19 .
  • the plurality of heat transfer pipes 19 is formed from steel and is formed as the flow path through which the boiler water supplied from the header 18 flows.
  • the plurality of heat transfer pipes 19 is disposed within the flow path a of the raw syngas, so that the pipes are heated by the heat of the raw syngas generated by the gasifier 1 .
  • the plurality of heat transfer pipes 19 is connected to the steam drum 16 so that the boiler water supplied from the header 18 is supplied to the steam drum 16 .
  • the ammonia addition equipment 12 is electrically connected to the control device 15 so as to enable transfer of information and accumulates ammonia solution.
  • the ammonia addition equipment 12 is controlled by the control device 15 to supply ammonia solution to the pipe line 30 so that ammonia solution is added to the boiler water supplied to the steam drum 16 from the condenser 8 .
  • the pH measurement device 14 is electrically connected to the control device 15 so as to enable transfer of information.
  • the pH measurement device 14 is controlled by the control device 15 to measure the pH of the boiler water accumulated in the steam drum 16 either at predetermined intervals or continuously.
  • the control device 15 is a computer that includes a CPU, a memory device, a memory drive, a communication device, and an interface, that are not illustrated on the drawings.
  • the interface outputs information generated by external equipment connected to the control device 15 to the CPU, and outputs information generated by the CPU to the external equipment.
  • the external equipment includes the ammonia addition equipment 12 and the pH measurement device 14 .
  • the computer programs installed in the control device 15 are formed from a plurality of computer programs to make the control device 15 realize a plurality of functions, as illustrated in FIG. 3 .
  • the plurality of functions includes a control circuit for normal operation 21 and a control circuit for preservation period 22 .
  • the pH measurement device 14 measures the pH of the boiler water accumulated in the steam drum 16 at least once.
  • the control circuit for normal operation 21 stores in advance an operational pH range in the memory device.
  • the set value in the operational pH range is, for example, 9.7.
  • the control circuit for normal operation 21 also controls the ammonia addition equipment 12 so that the pH of the boiler water accumulated in the steam drum 16 is within the operational pH range.
  • the control circuit for normal operation 21 controls the ammonia addition equipment 12 so that when the pH of the boiler water is less than the set value in the operational pH range, ammonia solution is supplied to the pipe line 30 .
  • the control circuit for normal operation 21 controls the ammonia addition equipment 12 so that when the pH of the boiler water is equal to or greater than the set value in the operational pH range, the ammonia solution is not supplied to the pipe line 30 .
  • the control circuit for preservation period 22 stores in advance a preservation pH range in the memory device.
  • the lower limit of the preservation pH range is equal to or greater than the set value in the operational pH range, for example, 9.7.
  • the control circuit for preservation period 22 also controls the ammonia addition equipment 12 so that the pH of the boiler water accumulated in the steam drum 16 is within the preservation pH range.
  • the control circuit for preservation period 22 controls the ammonia addition equipment 12 so that when the pH of the boiler water accumulated in the steam drum 16 is lower than the lower limit of the preservation pH range, ammonia solution is supplied to the pipe line 30 .
  • the control circuit for preservation period 22 controls the ammonia addition equipment 12 so that when the pH of the boiler water accumulated in the steam drum 16 is greater than the lower limit of the preservation pH range, ammonia solution is not supplied to the pipe line 30 .
  • the heat recovery steam generator 5 includes a water supply system that is not illustrated on the drawings.
  • the water supply system is formed similar to the water supply system 11 , in other words, it includes a steam drum, a plurality of downcast pipes, a header, and a plurality of heat transfer pipes.
  • the steam drum is formed into a vessel formed from steel.
  • the steam drum is connected to the pipe line 30 , and connected to the pipe line 31 .
  • the steam drum is also connected to the plurality of downcast pipes so that the boiler water accumulated in the inside of the steam drum is supplied to the plurality of downcast pipes.
  • Each of the plurality of downcast pipes is formed from steel and is formed as a flow path through which boiler water supplied from the steam drum flows.
  • Each of the plurality of downcast pipes is connected to the header so that the boiler water is supplied to the header.
  • the header is formed from steel, and formed as a vessel in which boiler water supplied from the plurality of downcast pipes is accumulated.
  • the header is connected to the plurality of heat transfer pipes so that the boiler water is supplied to the heat transfer pipes.
  • the plurality of heat transfer pipes is formed from steel and is and formed as a flow path through which the boiler water supplied from the header flows.
  • the plurality of heat transfer pipes is disposed in the flow path through which the exhaust gas flows, so that it is heated by the heat of the exhaust gas discharged from the gas turbine 3 .
  • the plurality of heat transfer pipes is connected to the steam drum so that the boiler water supplied from the header is supplied to the steam drum.
  • the embodiment of the boiler operation method according to the present invention is implemented using the integrated coal gasification combined cycle power plant 10 , and includes normal operation, preservation operation, and restart operation.
  • the gasifier 1 In normal operation, the gasifier 1 generates combustible high temperature raw syngas using air (or oxygen) supplied from external equipment, by pulverizing and burning coal as carbonaceous solid fuel supplied from external equipment.
  • the gas cooler 2 generates cooled raw syngas by heat exchange using the boiler water generated by the condenser 8 so as to cool the high temperature raw syngas generated by the gasifier 1 .
  • the gas cooler 2 generates high temperature high pressure steam by heat exchange using the heat of the high temperature raw syngas generated by the gasifier 1 to heat the boiler water.
  • the gas turbine 3 generates high temperature high pressure exhaust gas by burning the cooled raw syngas generated by the gas cooler 2 .
  • the gas turbine 3 generates rotational power using the kinetic energy of the exhaust gas, and discharges the exhaust gas.
  • the heat recovery steam generator 5 generates cooled exhaust gas by heat exchange using the boiler water generated by the condenser 8 to cool the high temperature exhaust gas discharged from the gas turbine 3 .
  • the heat recovery steam generator 5 generates high temperature high pressure steam by heat exchange using the heat of the high temperature exhaust gas discharged from the gas turbine 3 to heat the boiler water generated by the condenser 8 .
  • the steam turbine 6 generates rotational power using the kinetic energy of the high temperature high pressure steam generated by the gas cooler 2 and the kinetic energy of the high temperature high pressure steam generated by the heat recovery steam generator 5 , and discharges exhaust steam.
  • the generator 7 generates power using the rotational power generated by the gas turbine 3 and the rotational power generated by the steam turbine 6 .
  • the condenser 8 carries out heat exchange to cool the exhaust steam discharged by the steam turbine 6 to generate water as boiler water, and supplies the boiler water to the gas cooler 2 and the heat recovery steam generator 5 via the pipe line 30 .
  • the pH measurement device 14 measures the pH of the boiler water accumulated in the steam drum 16 of the gas cooler 2 .
  • the pH measurement device 14 transmits the measured pH to the control device 15 .
  • the control device 15 controls the ammonia addition equipment 12 to stop the addition of ammonia solution to the boiler water supplied to the steam drum 16 from the condenser 8 .
  • the control device 15 controls the ammonia addition equipment 12 to add ammonia solution to the boiler water supplied to the steam drum 16 from the condenser 8 .
  • the gas cooler 2 circulates the boiler water supplied from the condenser 8 to the water supply system 11 via the pipe line 30 to generate steam from the boiler water.
  • the plurality of downcast pipes 17 supplies the boiler water accumulated in the steam drum 16 to the header 18 .
  • the boiler water supplied from the plurality of downcast pipes 17 merge.
  • the plurality of heat transfer pipes 19 carries out heat exchange so that the boiler water that has merged at the heating pipe header 18 is heated using the heat of the high temperature raw syngas generated by the gasifier 1 , and the heated boiler water is supplied to the steam drum 16 .
  • the steam drum 16 accumulates the boiler water supplied from the condenser 8 via the pipe line 30 and the boiler water heated by the plurality of heat transfer pipes 19 .
  • liquid-vapor separation of the accumulated heated boiler water is carried out and the liquid-vapor separated steam is supplied to the steam turbine 6 .
  • the preservation operation is implemented immediately before stopping the integrated coal gasification combined cycle power plant 10 for periodic inspection, maintenance, and the like.
  • the control device 15 first measures the pH of the boiler water accumulated in the steam drum 16 using the pH measurement device 14 . When the measured pH is lower than the lower limit of the preservation pH range, the control device 15 controls the ammonia addition equipment 12 to supply ammonia solution to the pipe line 30 . When the measured pH is equal to or greater than the lower limit of the preservation pH range, the control device 15 controls the ammonia addition equipment 12 to stop the supply of ammonia solution to the pipe line 30 .
  • the water supply system 11 stops circulating the boiler water as a result of stopping the operation of the integrated coal gasification combined cycle power plant 10 .
  • oxygen is discharged from the spaces filled by gas within the water supply system 11 and the spaces are filled with pressurized nitrogen by injecting nitrogen under pressure.
  • FIG. 5 is a graph showing the relationship between pH and corrosion.
  • Test specimens were immersed in an ammonia solution with different pH within a sealed container under test conditions of oxygen saturation (25° C., 8 mg/L) and room temperature, and from the test results, it was determined whether or not there was corrosion by inspecting the surface, and the corrosion area was determined as a percentage of the total area.
  • oxygen saturation 25° C., 8 mg/L
  • room temperature room temperature
  • this preservation operation it is possible to achieve a greater reduction in the corrosion of the water supply system 11 during preservation of the equipment when the integrated coal gasification combined cycle power plant 10 is stopped, by filling the water supply system 11 with boiler water having pH within the preservation pH range compared with filling the water supply system 11 with boiler water having pH within the operational pH range.
  • the water supply system 11 is able to be preserved in a manner that it does not corrode during preservation of the equipment when the integrated coal gasification combined cycle power plant 10 is stopped.
  • the restart operation is implemented after implementation of the preservation operation, after the integrated coal gasification combined cycle power plant 10 has been stopped for a predetermined period of time.
  • the operation of the integrated coal gasification combined cycle power plant 10 is restarted and normal operation is implemented without removing the boiler water from the water supply system 11 and without re-supplying boiler water that satisfies the water quality for normal operation, unlike the conventional method of initiating restart after filling the water supply system 11 with preserved water that contains hydrazine during the equipment preservation period.
  • this restart operation it is possible to shorten the time required for restarting the integrated coal gasification combined cycle power plant 10 and restart in a shorter period of time than for a conventional restart operation, by not replacing the boiler water having a pH within the preservation pH range with boiler water having a pH within the operational pH range.
  • a similar boiler operation method as the embodiment described above is implemented using the integrated coal gasification combined cycle power plant 10 , the preservation operation in the embodiment as described above is replaced with another preservation operation, and the restart operation in the embodiment as described above is replaced with another restart operation.
  • the boiler water is removed from the water supply system 11 I as illustrated in FIG. 4 (Step S 1 ).
  • the water supply system 11 is filled with preserved water.
  • the preserved water contains 50 mg/L of hydrazine.
  • the air that contains oxygen is discharged from the spaces filled with gas within the water supply system 11 , and the spaces are filled with pressurized nitrogen by injecting with nitrogen under pressure (Step S 2 ).
  • the preserved water that contains hydrazine at a higher concentration than that of hydrazine suitable for normal operation is removed from the water supply system 11 (Step S 3 ).
  • the water supply system 11 is filled with boiler water (Step S 4 ).
  • the boiler water is formed from water that does not contain hydrazine.
  • ammonia is normally easier to obtain compared with hydrazine, and can be handled more easily.
  • the boiler water is not removed from the water supply system 11 before preservation of the water supply system 11 .
  • restarting operation without removing the boiler water having pH within the preservation pH range as a result of injecting ammonia solution, it is possible to implement the restart operation in a shorter period of time and at lower cost due to the boiler water not being discarded, compared with the restart operation after equipment preservation of the comparative example.
  • the restart operation by not removing the boiler water that filled the water supply system 11 during equipment preservation, it is possible to omit the step of filling the water supply system 11 with preserved water that contains hydrazine after removal of the boiler water from the water supply system 11 in order to start the equipment preservation after stopping the integrated coal gasification combined cycle power plant 10 .
  • the operation executed by the control device 15 can be executed by a user.
  • the pH of the boiler water accumulated in the steam drum 16 of the gas cooler 2 is measured by the user by controlling the pH measurement device 14 .
  • ammonia addition equipment 12 By operating the ammonia addition equipment 12 , ammonia solution is added to the pipe line 30 and the addition of the ammonia solution is stopped.
  • the integrated coal gasification combined cycle power plant 10 can be stopped in a shorter period of time and can be restarted in a shorter period of time.
  • the gas cooler 2 and the heat recovery steam generator include a boiler, so the above effect can be exhibited.
  • the boiler includes the water supply system through which the boiler water to be heated flows, ammonia addition equipment that adds ammonia to the boiler water, and the pH measurement device that measures the pH of the boiler water.
  • the control circuit for preservation period 22 of the embodiment as described above is replaced with another control circuit for preservation period.
  • a plurality of preservation pH ranges corresponding to a plurality of preservation periods is stored in advance in the memory device.
  • Each of the plurality of preservation pH ranges has a lower limit that is equal to or greater than the set value in the operational pH range.
  • the lower limit of the preservation pH range corresponding to a period equal to or less than 24 hours may be 9.5.
  • the lower limit of the preservation pH range corresponding to a period equal to or less than 72 hours may be 9.7.
  • the lower limit of the preservation pH range corresponding to a period from 4 days to 7 days may be 9.8.
  • the lower limit of the preservation pH range corresponding to a period from 7 days to 14 days may be 9.9.
  • the lower limit of the preservation pH range corresponding to a period from 15 days to 30 days may be 10. The longer the preservation period, the higher the corresponding lower limit of the preservation pH range.
  • the upper limit of the preservation pH is less than pH 11, because of the possibility of alkaline corrosion even in steel that is normally strongly alkali resistant.
  • this is not a limitation.
  • a control circuit for preservation operation calculates a preservation pH range corresponding to the preservation period from the plurality of preservation pH ranges.
  • the control circuit for preservation operation controls the pH measurement device 14 to measure the pH of the boiler water accumulated in the steam drum 16 .
  • the control circuit for preservation period controls the ammonia addition equipment 12 so that the pH of the boiler water accumulated in the steam drum 16 is within the preservation pH range.
  • the ammonia addition equipment 12 may be operated by a manual operation, and is not limited to calculating the preservation pH range corresponding to the preservation period, and controlling the ammonia addition equipment 12 .
  • the integrated coal gasification combined cycle power plant that includes such a control circuit for preservation period can more easily suppress the corrosion of the water supply system 11 , can stop in a shorter period of time, and can restart in a shorter period of time, similar to the integrated coal gasification combined cycle power plant 10 according to the embodiment as described above.
  • FIG. 5 shows the relationship between pH of the preserved water and corrosion.
  • This relationship shows the pH of the preserved water in which test specimens formed from the steel are immersed, and shows the corrosion area corresponding to the number of days elapsed after immersing the test specimens in the preserved water.
  • the corrosion area shows the area of the region that is corroded after the elapsed time as a percentage of the area of the surface of the test specimen in contact with the preserved water.
  • this relationship shows the progression of corrosion with time.
  • this relationship shows that the higher the pH of the preserved water, the longer the time at which corrosion of the test specimens starts is delayed. Therefore, this relationship shows that the greater the pH of the boiler water filling the water supply system 11 during preservation, the longer the period of time that corrosion can be prevented.
  • preservation pH range can be replaced with another preservation pH range whose lower limit is 9.5.
  • the lower limit of the preservation pH range is equal to the set value in the operational pH range, or, is greater than the set value in the operational pH range.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
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  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
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  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Preventing Corrosion Or Incrustation Of Metals (AREA)
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JP2013031404A JP5960077B2 (ja) 2013-02-20 2013-02-20 ボイラ運転方法およびボイラ
PCT/JP2014/050970 WO2014129244A1 (ja) 2013-02-20 2014-01-20 ボイラ運転方法およびボイラ

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20170002694A1 (en) * 2015-07-02 2017-01-05 Mitsubishi Hitachi Power Systems, Ltd. Thermal Power Plant for Recovering Water from Exhaust Gas and a Method for Treating Recovered Water of Thermal Power Plant Thereof
CN111412965A (zh) * 2020-04-01 2020-07-14 江苏核电有限公司 一种二回路化学工况调节系统试剂箱液位报警设置方法
US11802688B2 (en) 2017-10-17 2023-10-31 Mitsubishi Heavy Industries, Ltd. Seawater leakage detection device in feedwater system, method for detecting seawater leakage in feedwater system, and steam turbine plant

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016189950A1 (ja) * 2015-05-28 2016-12-01 三浦工業株式会社 バラスト水処理装置及びバラスト水処理方法
JP6830072B2 (ja) * 2018-01-22 2021-02-17 水ｉｎｇ株式会社 ボイラの防食方法及びボイラ設備
JP7150594B2 (ja) 2018-12-27 2022-10-11 三菱重工業株式会社 ボイラプラントの洗浄保管方法および洗浄保管装置
CN114074982A (zh) * 2020-08-14 2022-02-22 云南聚杰环保科技有限公司 一种工业汽包炉汽包水加碱性强电解质防腐防垢技术
JP7581079B2 (ja) 2021-02-24 2024-11-12 三菱重工業株式会社 ボイラの保管装置およびこれを備えたボイラならびにボイラの保管方法

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4905721A (en) * 1989-05-11 1990-03-06 Betz Laboratories, Inc. Monitoring and controlling AVT (all volatile treatment) and other treatment programs for high pressure boilers via the conductivity control method
EP0640747A1 (en) * 1993-08-20 1995-03-01 Nalco Chemical Company Boiler system pH/phosphate program control method
KR20060002763A (ko) * 2003-02-11 2006-01-09 후지츠 트랜색션 솔루션즈 인코포레이티드 무인계산 시스템을 위한 복수 장치 관리자 지원
KR100569761B1 (ko) * 2004-09-23 2006-04-11 주식회사 포스코 보일러의 수질상태 진단 및 자동제어장치와 방법
US20060157420A1 (en) * 2004-11-30 2006-07-20 Hays George F Automated process for inhibiting corrosion in an inactive boiler containing an aqueous system
US20070084418A1 (en) * 2005-10-13 2007-04-19 Gurevich Arkadiy M Steam generator with hybrid circulation
US20070180768A1 (en) * 2006-02-09 2007-08-09 Siemens Power Generation, Inc. Advanced ASU and HRSG integration for improved integrated gasification combined cycle efficiency
US20100163399A1 (en) * 2006-08-31 2010-07-01 Mitsubishi Heavy Industries, Ltd. Water Treatment Process for Steam Plant

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH076606B2 (ja) * 1985-05-08 1995-01-30 株式会社日立製作所 複合発電プラントの水処理方法
JPS63105302A (ja) * 1986-10-22 1988-05-10 バブコツク日立株式会社 発電プラントにおける給水処理方法
US5327330A (en) * 1993-04-07 1994-07-05 Ford Motor Company Inner sealed lamp-within-a lamp headlamp for a motor vehicle
JPH08219405A (ja) * 1995-02-16 1996-08-30 Kyushu Electric Power Co Inc ボイラ設備の防食方法
JP4080849B2 (ja) * 2002-11-20 2008-04-23 中部電力株式会社 ボイラの管理方法
JP4983069B2 (ja) * 2006-03-31 2012-07-25 栗田工業株式会社 純水給水ボイラ水系処理方法および処理装置
JP4993568B2 (ja) * 2006-09-22 2012-08-08 中国電力株式会社 発電プラントの停止・起動時の水処理方法及びその装置
US20110070123A1 (en) 2008-03-27 2011-03-24 Jan Stodola Corrosion reduction system for power generation plants during shutdown
JP5439942B2 (ja) * 2009-05-14 2014-03-12 栗田工業株式会社 簡易ボイラにおける水処理剤添加方法
JP2010185655A (ja) * 2010-04-01 2010-08-26 Miura Co Ltd ボイラ装置の腐食抑制方法
CN102519030A (zh) * 2012-01-10 2012-06-27 广东电网公司电力科学研究院 一种热力设备停运保养方法
CN102838227A (zh) * 2012-08-16 2012-12-26 浙江东发环保工程有限公司 将工业园区中水处理为电厂锅炉补给水的处理系统及方法

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4905721A (en) * 1989-05-11 1990-03-06 Betz Laboratories, Inc. Monitoring and controlling AVT (all volatile treatment) and other treatment programs for high pressure boilers via the conductivity control method
EP0640747A1 (en) * 1993-08-20 1995-03-01 Nalco Chemical Company Boiler system pH/phosphate program control method
KR20060002763A (ko) * 2003-02-11 2006-01-09 후지츠 트랜색션 솔루션즈 인코포레이티드 무인계산 시스템을 위한 복수 장치 관리자 지원
KR100569761B1 (ko) * 2004-09-23 2006-04-11 주식회사 포스코 보일러의 수질상태 진단 및 자동제어장치와 방법
US20060157420A1 (en) * 2004-11-30 2006-07-20 Hays George F Automated process for inhibiting corrosion in an inactive boiler containing an aqueous system
US20070084418A1 (en) * 2005-10-13 2007-04-19 Gurevich Arkadiy M Steam generator with hybrid circulation
US20070180768A1 (en) * 2006-02-09 2007-08-09 Siemens Power Generation, Inc. Advanced ASU and HRSG integration for improved integrated gasification combined cycle efficiency
US20100163399A1 (en) * 2006-08-31 2010-07-01 Mitsubishi Heavy Industries, Ltd. Water Treatment Process for Steam Plant

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Rajajovic-Ognajanovic, Vladana et al, Improvement of chemical control in the water-stream cycle of thermal power plants, 2011, Elsevier, Applied Thermal Engineering, pp. 119-128. *
Tsubakizaki Alternative to Hydrazine in Water Treatment at Thermal Power Plants as referenced in OA dated 2/21/2019 *
Tsubakizaki, Senichi et al, ALternatives to Hydrazine in Water Treatment at Thermal Power Plants, June 2009, Mitsubishi Heavy Industries Technical Review Vol. 46 No. 2, pp 43-47. *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20170002694A1 (en) * 2015-07-02 2017-01-05 Mitsubishi Hitachi Power Systems, Ltd. Thermal Power Plant for Recovering Water from Exhaust Gas and a Method for Treating Recovered Water of Thermal Power Plant Thereof
US10107144B2 (en) * 2015-07-02 2018-10-23 Mitsubishi Hitachi Power Systems, Ltd. Thermal power plant for recovering water from exhaust gas and a method for treating recovered water of thermal power plant thereof
US11802688B2 (en) 2017-10-17 2023-10-31 Mitsubishi Heavy Industries, Ltd. Seawater leakage detection device in feedwater system, method for detecting seawater leakage in feedwater system, and steam turbine plant
CN111412965A (zh) * 2020-04-01 2020-07-14 江苏核电有限公司 一种二回路化学工况调节系统试剂箱液位报警设置方法

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WO2014129244A1 (ja) 2014-08-28
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