JP2016057009A - Boiler and suspension processing method for boiler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a boiler and a suspension processing method of the boiler, in which operation of the boiler can be quickly started when releasing the suspension processing.SOLUTION: Provided is a boiler 2 to which suspension processing is performed, which includes: boiler feed water supplying means 6 for supplying boiler feed water W1 to a boiler body 21 so that a water volume of boiler water W2 becomes a preset water storage volume in performing the suspension processing of the boiler 2; agent supplying means 81 capable of performing agent supply processing for supplying an agent to the boiler feed water W1; and an agent supply control unit 103 for making the agent supply means 81 perform the agent supply processing when suspending the boiler 2, so that a required amount of agent is supplied to the boiler feed water W1 to make a pH value of the boiler water W2 stored at the set storage volume be 12 or more, on the basis of a detected water level and a detected pH value of the boiler water W2 when stopping the combustion of the boiler 2.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a boiler in which a can resting process for stopping use of a boiler body is executed, and a rest processing method for the boiler.

  If the boiler operation is suspended for a long period of time (for example, one week or more) while the boiler water is stored in the boiler body, the boiler body may be corroded due to acidification of the boiler water. For this reason, when the operation of the boiler is suspended for a long period of time, it is necessary to suppress the corrosion of the boiler body.

  2. Description of the Related Art Conventionally, as a can rest treatment method for stopping use of a boiler body, there is a method of filling the boiler body with water containing chemicals and storing it while suppressing corrosion inside the boiler body (see, for example, Patent Document 1). In addition, as a can resting treatment method that stops the use of the boiler body, a vaporizing rust preventive is added to the boiler body after the blow process (all blow process) for discharging all the boiler water in the boiler body to the outside. There is a method of injecting, forming a film on the metal surface in the boiler body, and storing while suppressing corrosion in the boiler body.

In the boiler rest treatment method described in Patent Document 1, after the boiler water is completely blown, the boiler body is filled with water containing chemicals (chemical solution) and stored. In addition, when the boiler can be released (when the boiler main body is used and the boiler main body is started to be used), when the boiler is started, all the chemicals are blown to the boiler. There is a need to inspect the inside of the main body and then supply water to the boiler main body to start using the boiler.
In addition, in the boiler canning treatment method in which chemicals such as a vaporizable rust preventive agent are injected into the boiler body, when the boiler is started, when the boiler canning treatment is canceled, In order to remove chemicals such as rusting agents, it is necessary to clean the boiler body.

JP 2002-129366 A

  In the conventional boiler can processing method, when the boiler can processing is canceled, it becomes necessary to inspect the inside of the boiler body by blowing all the chemicals, or to clean the boiler body. Therefore, it takes time to start the boiler. For example, a boiler may be stored as a backup boiler. This backup boiler is desirably activated promptly when an emergency occurs in the boiler that is normally used and the boiler cannot be used.

  An object of this invention is to provide the boiler which can start a boiler rapidly at the time of cancellation | release of a can rest process, and the can rest processing method of a boiler.

  The present invention is a boiler in which a can resting process for stopping the use of a boiler body in which boiler water is stored as boiler water is executed, the water level of the boiler water being continuously detectable, and the boiler A water level detecting means for detecting the water level of the boiler water when the combustion of the boiler is stopped, a pH value detecting means for directly or indirectly detecting a pH value of the boiler water when the combustion of the boiler is stopped, and a boiler can The boiler water supply means for supplying boiler water to the boiler body and the chemical supply process for supplying chemical to the boiler water can be executed so that the amount of boiler water becomes a preset water storage amount at the time of processing. When the boiler resting process is performed, the stored water is stored in the set water storage amount based on the detected water level value and the detected pH value of the boiler water when the boiler combustion is stopped. As the drug in an amount necessary for pH value of the boiler water is 12 or more is supplied to the boiler feed water, to a boiler and a drug supply control unit for executing the agent supply process in the drug supply means.

  The set water storage amount is preferably a full water storage amount when the boiler body is full, or a startup water storage amount when the boiler is started.

  Further, when the set water storage amount is the startup water storage amount, it is preferable that nitrogen gas is enclosed in a space above the boiler water stored up to the startup water storage amount in the boiler body. .

  In addition, the detected pH value is a pH value that is directly detected by a pH value sensor, a pH value that is indirectly detected by converting from the electrical conductivity of the boiler water, or the boiler water It is preferable to include a pH value that is indirectly detected in terms of acid consumption (pH 8.3).

  Further, the present invention is a boiler can processing method for executing a can resting process for halting use of a boiler body in which boiler water is stored as boiler water, and at the time of executing the boiler rest processing The boiler water is supplied to the boiler body so that the amount of boiler water becomes a preset water storage amount, and is set based on the detected water level value and the detected pH value of the boiler water when the boiler stops combustion. The present invention relates to a boiler can resting method for executing a chemical supply process so that a necessary amount of chemicals for supplying a boiler water having a pH value of 12 or more is supplied to boiler feed water.

  The set water storage amount is preferably a full water storage amount when the boiler body is full, or a startup water storage amount when the boiler is started.

  Further, when the set water storage amount is the startup water storage amount, it is preferable that nitrogen gas is sealed in a space above the boiler water stored up to the startup water storage amount in the boiler body.

  In addition, the detected pH value is a pH value that is directly detected by a pH value sensor, a pH value that is indirectly detected by converting from the electrical conductivity of the boiler water, or the boiler water It is preferable to include a pH value that is indirectly detected in terms of acid consumption (pH 8.3).

  ADVANTAGE OF THE INVENTION According to this invention, the boiler which can start a boiler quickly at the time of cancellation | release of a can rest process and the can rest processing method of a boiler can be provided.

It is a figure showing the outline of boiler system 1 concerning a 1st embodiment of the present invention. It is a functional block diagram concerning control of boiler system 1 of a 1st embodiment. It is a flowchart which shows the process sequence at the time of execution of the can rest process in the boiler 2 of 1st Embodiment. It is a figure which shows the outline of 1 A of boiler systems which concern on 2nd Embodiment of this invention.

(First embodiment)
Hereinafter, with reference to drawings, boiler system 1 concerning a 1st embodiment of the present invention is explained. FIG. 1 is a diagram showing an outline of a boiler system 1 according to the first embodiment of the present invention. As shown in FIG. 1, the boiler system 1 of the first embodiment includes a boiler 2, a hard water softening device 3, a water supply tank 5, a chemical addition device 81, a control device 10, and a steam header 50. . With the boiler 2 of the first embodiment, the first embodiment of the can resting method for the boiler 2 of the present invention is implemented. In FIG. 1, a path of electrical connection is indicated by a broken line.

  Moreover, the boiler system 1 is provided with the hardness sensor 41 and the electrical conductivity sensor 42 as a pH value detection means.

  The boiler system 1 includes a water supply line L1, a fuel supply line L2, a blow line L3, a steam discharge line L4, a steam delivery line L5, a precipitation line L6, a chemical addition line L7, and a drain water recovery line. L8. The “line” in the present specification is a general term for lines capable of flowing a fluid such as a flow path, a path, and a pipeline.

  In the boiler 2, the can rest process mentioned later is performed. The boiler rest process of the boiler 2 is executed in order to suppress corrosion inside the boiler main body 21 when the use of the boiler main body 21 is stopped for a long period of time, for example, for one week or longer. The boiler 2 generates steam to be supplied to steam use equipment (not shown). The boiler 2 includes a boiler body 21, a burner 27, a combustion chamber 26, a water level detector 28 as water level detection means, a feed water pump 6 as boiler feed water supply means, a steam / water separator 7, and a blow valve 93. A main steam valve 94, a steam check valve 95, and a steam pressure measuring unit 29. The boiler body 21 forms a pressure vessel including a plurality of water pipes 22, an upper header 23, and a lower header 24.

As will be described later, the boiler 20 according to the present embodiment has a multi-tube once-through boiler structure. In addition, the one with a gauge pressure of 1 MPa or less and a heat transfer area of 10 m ² or less is referred to as a small once-through boiler (Occupational Safety and Health Law Enforcement Ordinance, Article 4, Item 4).

  The water supply line L <b> 1 is a line that supplies the boiler water supply W <b> 1 to the boiler body 21. The upstream end of the water supply line L1 is connected to a supply source (not shown) of the boiler water supply W1. The downstream end of the water supply line L <b> 1 is connected to a lower header 24 (described later) of the boiler body 21. The water supply line L1 is provided with a water softening device 3, a hardness sensor 41, a water supply tank 5, a connection portion J1, and a water supply pump 6 in order from the supply source to the boiler 2.

  The hard water softening device 3 generates soft water by replacing hardness components contained in raw water such as tap water, ground water, and industrial water with sodium ions (or potassium ions). The water softening device 3 has a cation exchange resin bed 3a. The cation exchange resin bed 3a performs water softening treatment of the boiler feed water W1 supplied to the boiler body 21. The water softening device 3 supplies treated water (soft water) obtained by softening the raw water W0 with the cation exchange resin bed 3a toward the boiler 2 as boiler feed water W1.

  The hardness sensor 41 detects the hardness of the boiler feed water W <b> 1 softened by the water softening device 3. Information regarding the hardness of the boiler feed water W <b> 1 detected by the hardness sensor 41 is transmitted to the control device 10 as a detection signal.

  The feed water tank 5 stores the treated water softened by the hard water softening device 3 as boiler feed water W1. Boiler feed water W <b> 1 stored in the feed water tank 5 is supplied to the boiler body 21 by the feed water pump 6. The feed water pump 6 sucks the boiler feed water W1 from the feed water tank 5, and sends the boiler feed water W1 flowing through the feed water line L1 toward the boiler body 21.

  The water supply pump 6 uses the boiler feed water W1 as boiler water W2 so that the amount of boiler water W2 stored in the boiler body 21 becomes a preset full water storage amount when the boiler rest process of the boiler 2 is executed. Supply to the main body 21. The full water storage amount is a water storage amount of the boiler water W2 in a state where the boiler body 21 (a plurality of water pipes 22, an upper header 23, and a lower header 24 described later) is filled with the boiler water W2. When the boiler water W2 is stored in the boiler main body 21 in the full water storage amount, the boiler water W2 reaches the upper end of the upper header 23 in the boiler main body 21 (a plurality of water pipes 22, upper header 23, and lower header 24 described later). Stored.

  The downstream end of the drug addition line L7 is connected to the connecting part J1. A drug addition device 81 as a drug supply means is connected to the upstream end of the drug addition line L7. The drug addition device 81 is a device for adding (supplying) a drug to the boiler feed water W1. The chemical addition device 81 can execute a chemical supply process for supplying chemicals to the boiler feed water W <b> 1 when the boiler 2 is started, during normal operation, or when a can rest process is executed. As the drug, one containing a pH adjuster is used. The pH adjuster is for suppressing corrosion inside the boiler body 21 by adjusting the pH value of the boiler water W2 to the alkaline side. Examples of the pH adjuster include, for example, a distribution ratio of an alkali metal hydroxide (sodium hydroxide, potassium hydroxide, etc.), an amine compound (2-amino-2-methyl-1-propanol, diethanolamine, etc.) / Volatile amine) / ammonia etc. with a relatively low concentration in the liquid phase). The chemical | medical agent containing a pH adjuster is prepared as a composite canning agent with components, such as a scale inhibitor and another corrosion inhibitor, for example.

  In this embodiment, at the time of execution of a can resting process, the chemical addition device 81 supplies the boiler water supply so that the boiler water W2 has a pH value of 12 or more with respect to the boiler water W2 stored up to the full water storage amount. Supply drug to W1.

  When the pH value of the boiler water W2 is 12 or more at the time of performing the can resting process, the effect of suppressing the corrosion of the boiler body 21 is high, and it can be said that the boiler water W2 is in the corrosion-inhibiting water quality. On the other hand, if the pH value is lower than 12, which is the lower limit value of the pH value having a high corrosion inhibitory effect, there is a risk of corrosion of the boiler body 21 during the can resting process.

  As the pH adjuster used for setting the boiler water W2 to have a pH value of 12 or more during the can resting process, the same pH value adjuster used when the boiler 2 is started or during normal operation is used. Preferably, for example, alkali metal hydroxide (sodium hydroxide, potassium hydroxide, etc.) or ammonia is used. The addition amount of the medicine necessary for setting the pH value of the boiler body 21 to 12 or more is calculated by the medicine addition control unit 103 described later.

  The drug addition device 81 is electrically connected to the control device 10. Timing and amount of addition of the drug from the drug addition device 81 to the connection portion J2 of the water supply line L1 are controlled by a drive signal transmitted from a drug addition control unit 103 (described later) of the control device 10.

  The boiler body 21 is composed of a group of water pipes erected in the vertical direction between the upper and lower headers, and constitutes the main part of the outer shape of the boiler 2. In the boiler body 21, the boiler feed water W1 supplied through the feed water line L1 is stored as boiler water W2. The boiler water W2 includes water that once accumulates in the boiler body 21 as the boiler water W2 and then taken out as steam and returns to the boiler body 21. For example, the boiler water W <b> 2 includes separated water W <b> 4 that is separated by the steam separator 7 (described later) and returned to the boiler body 21.

  Inside the boiler body 21, boiler water W2 is stored. The boiler body 21 includes a plurality of water pipes 22, an upper header 23, and a lower header 24. The plurality of water pipes 22 are arranged extending in the vertical direction of the boiler body 21. The upper header 23 is disposed on the upper portion of the boiler body 21. The upper header 23 is configured by, for example, an annular container. The upper header 23 is connected to upper ends of a plurality of water pipes 22. The upper header 23 is also referred to as “upper header”. The upper header 23 is connected to one end of a steam extraction line L4 described later.

  The upper header 23 is provided with a vapor pressure measuring unit 29. The vapor pressure measuring unit 29 measures the vapor pressure inside the boiler body 21. The vapor pressure measuring unit 29 is constituted by, for example, a vapor pressure sensor and a vapor pressure switch or only a vapor pressure switch, and measures the vapor pressure inside the upper header 23 of the boiler body 21. Information regarding the steam pressure inside the boiler body 21 measured by the steam pressure measuring unit 29 is transmitted to the control device 10 as a detection signal.

  The lower header 24 is disposed below the boiler body 21. The lower header 24 is constituted by, for example, an annular container. The lower header 24 is connected to lower ends of the plurality of water pipes 22. The lower header 24 is also referred to as “lower header”. One end of the side wall of the lower header 24 is connected to the end of the water supply line L1. The other end of the side wall of the lower header 24 is connected to the end of the precipitation line L6. The combustion chamber 26 is configured by a space surrounded by a plurality of water pipes 22.

  The burner 27 heats the inside of the boiler body 21 by burning. The burner 27 is disposed in the central portion on the upper side of the boiler body 21. The burner 27 includes a fuel injection nozzle and an air supply nozzle (both not shown). The burner 27 injects fuel from the fuel injection nozzle toward the combustion chamber 26 of the boiler body 21 and supplies air from the air supply nozzle into the boiler body 21 to burn the fuel.

  The water level detector 28 is a device that can continuously detect the water level of the boiler water W2 stored in the water pipe 22 (boiler body 21). When the power of the boiler 2 is on, the water level detector 28 determines the water level of the boiler water W2. Always detect. That is, the water level detector 28 can detect the water level of the boiler water W2 when the combustion of the boiler 2 is stopped. Further, the water level detector 28 can detect the level of the boiler water W2 when the boiler body 21 is cooled after the combustion of the boiler 2 is stopped. The water level detector 28 is electrically connected to the control device 10. The detection signal of the boiler water W2 detected by the water level detector 28 is transmitted to the control device 10.

  In the present embodiment, the water level detector 28 is a continuous level sensor, and for example, a capacitance type sensor, a pressure type sensor, an ultrasonic type sensor or the like is used. FIG. 1 shows an example in which a capacitive sensor is provided as the water level detector 28. The water level detector 28 includes a water level detection cylinder 28a and an electrode rod 28b. The upper end of the water level detection cylinder 28a is connected to the upper header 23 via a connection line. The lower end portion of the water level detection cylinder 28a is connected to the lower header 24 via a connection line. The water level detection cylinder 28 a has an upper end connected to the upper header 23 and a lower end connected to the lower header 24, thereby storing the boiler water W <b> 2 at the same level as the water pipe 22. The water level detector 28 uses the insulating film coated on the surface of the electrode rod 28b as a dielectric, and measures the electrostatic capacitance between the electrode rod 28b and the water level detection tube 28a, so that the water level detector 28a is inside the water level detection tube 28a. It is possible to detect the water level of the boiler water W2 in contact with the electrode rod 28b. The water level detector 28 can continuously detect the change in the water level of the boiler water W2 inside the water level detection cylinder 28a based on the change in the measured capacitance.

  The fuel supply line L <b> 2 is a line that supplies the fuel F burned by the burner 27 to the burner 27. The upstream end of the fuel supply line L2 is connected to a fuel F supply source (not shown). The downstream end of the fuel supply line L2 is connected to the burner 27. A fuel supply valve 92 is provided in the fuel supply line L2. The fuel supply valve 92 is a valve that adjusts the amount of fuel supplied to the burner 27. The fuel supply valve 92 can open and close the fuel supply line L2. The opening and closing of the valve body in the fuel supply valve 92 is controlled by a drive signal from the control device 10.

  The steam extraction line L4 is a line for taking out the wet steam SM1 generated in the water pipe 22 from the upper header 23 and introducing it into the steam separator 7. The upstream end of the steam extraction line L4 is connected to the upper surface of the upper header 23 of the boiler body 21. The downstream end portion of the steam extraction line L4 is connected to the upper side of the side portion of the steam / water separator 7.

  The steam separator 7 is a device that separates the wet steam SM1 introduced from the upper header 23 through the steam extraction line L4 into dry steam SM2 and moisture (hereinafter also referred to as “separated water W4”). As described above, the separated water W4 separated by the steam separator 7 is also a part of the boiler water W2.

  The steam delivery line L <b> 5 is a line that sends out the dry steam SM <b> 2 separated by the steam separator 7 toward the steam header 50. The upstream end of the steam delivery line L5 is connected to the upper surface of the steam separator 7. The downstream end of the steam delivery line L <b> 5 is connected to the steam header 50.

  The steam delivery line L5 is provided with a main steam valve 94, a steam check valve 95, and a steam header 50 in order from the steam / water separator 7 to a load device (not shown). The main steam valve 94 is a valve that can manually switch the open / close state of the steam delivery line L5. The steam check valve 95 is a valve that prevents the backflow of the steam SM3 from the steam header 50.

  The steam header 50 is equipment for collecting dry steam SM2 from a plurality of installed boilers (not shown) and distributing the collected steam SM3 to steam using equipment (not shown). The steam header 50 is connected to the upstream end of the drain water recovery line L8.

  The drain water recovery line L8 is a line for recovering the generated drain water W5 to the water supply tank 5 when the condensation of the steam SM3 occurs in the steam header 50. The drain water recovery line L8 is provided with a steam trap 32 for separating the drain water from the steam SM3. The downstream end of the drain water recovery line L8 is connected to the water supply tank 5.

  The precipitation line L6 is a line that causes the separated water W4 separated by the steam separator 7 to flow toward the lower header 24 of the boiler body 21. The upstream end of the precipitation line L6 is connected to the lower part of the steam separator 7. The downstream end of the precipitation line L <b> 6 is connected to the lower header 24. The precipitation line L6 is provided with a connection portion J2 and an electrical conductivity sensor 42 in order from the steam separator 7 toward the lower header 24. The precipitation line L6 is also referred to as a “precipitation pipe”.

  The electrical conductivity sensor 42 is a sensor that detects the electrical conductivity of the separated water W4 that flows through the precipitation line L6 (downcomer). The separated water W4 flowing through the precipitation line L6 (precipitation pipe) is a part of the boiler water W2. The electrical conductivity sensor 42 indirectly detects the pH value of the boiler water W2 when the combustion of the boiler 2 is stopped. In the present embodiment, the electrical conductivity value detected by the electrical conductivity sensor 42 is converted into a pH value by the drug addition control unit 103 described later. The electrical conductivity sensor 42 is electrically connected to the control device 10. The electrical conductivity value of the separated water W4 (boiler water W2) detected by the electrical conductivity sensor 42 is transmitted to the control device 10 as a detection signal.

  The upstream end of the blow line L3 is connected to the connecting part J2. The blow line L3 is a line that discharges the separated water W4 (boiler water W2) flowing through the precipitation line L6 (precipitation pipe) to the outside of the boiler 2 via the connection portion J2. A blow valve 93 is provided in the blow line L3. The opening / closing of the blow valve 93 is controlled by a drive signal from the control device 10. By opening the blow valve 93, the separated water W4 (boiler water W2) flowing through the precipitation line L6 (precipitation pipe) is discharged to the outside.

  Next, with reference to FIG. 2, the function which concerns on control of the boiler system 1 of this embodiment is demonstrated. FIG. 2 is a functional block diagram relating to the control of the boiler system 1 of the present embodiment. The control apparatus 10 controls each part in the boiler system 1 of this embodiment. The control device 10 is electrically connected to each measurement device in the boiler system 1 and receives measurement information from each measurement device. Further, the control device 10 is electrically connected to the feed water pump 6 and controls the feed water pump 6 so as to send out the boiler feed water W <b> 1 toward the boiler 2 in accordance with the water level of the boiler water W <b> 2 in the boiler body 21.

  In addition, the control device 10 includes a control unit 100 and a memory unit 110. The control unit 100 includes a valve control unit 101, a vapor pressure determination unit 102, and a drug addition control unit 103 as a drug supply control unit.

  The valve control unit 101 controls the open / close state of the fuel supply valve 92 and the blow valve 93. The vapor pressure determination unit 102 determines whether or not the vapor pressure inside the boiler body 21 measured by the vapor pressure measurement unit 29 is equal to or lower than a predetermined pressure value. If the steam pressure inside the boiler body 21 becomes equal to or lower than a predetermined pressure value after the combustion of the boiler 2 is stopped, it can be considered that the inside of the boiler body 21 has been cooled.

  The control unit 100 controls the feed water pump 6 so as to supply the boiler feed water W1 to the boiler main body 21 so that the amount of the boiler water W2 becomes a preset start-up water storage amount when the boiler 2 is started. . Thereby, at the time of starting of the boiler 2, the amount of water of the boiler water W2 becomes the amount of stored water at the time of starting.

  The control unit 100 controls the water supply pump 6 so that the amount of water stored in the boiler water W2 becomes a full water storage amount (a preset water storage amount set in advance) when the boiler rest process of the boiler 2 is executed. Thereby, at the time of execution of the can resting process of the boiler 2, the water storage amount of the boiler water W2 becomes the full water storage amount.

  Here, at the time of execution of the can resting process of the boiler 2, the feed water pump 6 supplies the boiler feed water W <b> 1 of the forced feed water amount to the boiler body 21 in order to set the stored water amount of the boiler water W <b> 2 to the full water storage amount. The forced water supply amount is the amount of water that is forcibly supplied to the boiler main body 21 so as to be the full water storage amount during the can resting process.

  Here, a method for calculating the forced water supply amount will be described. When the boiler 2 executes the can resting process, the operation of the boiler 2 is stopped. Here, when the operation of the boiler 2 is stopped, the inside of the boiler body 21 is cooled, for example, the steam inside the boiler body 21 and the steam separator 7 is condensed, and the boiler water W2 increases. Therefore, during the period from when the combustion of the boiler 2 is stopped until the inside of the boiler body 21 is cooled, the amount of stored water corresponding to the condensed water may increase from the amount of stored water of the boiler water W2 when the combustion of the boiler 2 is stopped. is there. For this reason, when water is supplied up to the full water storage amount during the can resting process of the boiler 2, the water is supplied so as to be the full water storage amount in consideration of the storage amount of the increased amount of condensed water.

For example, a full water reservoir capacity and V _1, the forced water supply and V _X, when the cooling time reservoir capacity of boiler water W2 when interior cooling of the boiler body 21 and a V _2, forced water supply amount V _X is Is calculated by the following equation (1). The full water storage amount V ₁ is the total capacity of the boiler body 21 and is set in advance.
V _X = V ₁ −V ₂ (1)

Upon cooling water storage amount V ₂ is the water level detector 28 detects the water level when the internal cooling of the boiler body 21 can be calculated based on the detection level. The inside of the boiler body 21 can be cooled when the steam pressure inside the boiler body 21 becomes a predetermined pressure value or less after the combustion of the boiler 2 is stopped.

Incidentally, supplied as described above, to the water amount of the boiler water W2 of the boiler body 21 and the full water reservoir capacity V _1, to calculate the force water supply V _X, the boiler feed water W1 forced water supply V _X The feed water pump 6 is controlled as described above, but is not limited thereto. For example, the upper header 23 is provided with a full water detection sensor (not shown) that can detect that the boiler body 21 is full, and the water supply pump 6 is driven when the full water detection sensor detects that the boiler body 21 is full. It stops and it is good also considering the water storage amount of the boiler water W2 as a full water storage amount. As the full water detection sensor, for example, an electrode type level switch can be used.

  The chemical addition control unit 103 adds chemicals to the boiler feed water W <b> 1 so that the water quality of the boiler water W <b> 2 becomes a corrosion-suppressing water quality that can suppress the corrosion of the boiler body 21 at the start-up and normal operation of the boiler 2. The supply processing is executed by the medicine addition device 81. Thereby, the water quality of the boiler water W2 maintained at the starting water storage amount is maintained so as to be the corrosion-suppressing water quality.

  The chemical addition control unit 103 performs boiler water W2 stored in the full water storage amount based on the detected water level value and the detected pH value of the boiler water W2 when the combustion of the boiler 2 is stopped when the boiler 2 is closed. The medicine supply device 81 is caused to execute a medicine supply process so that the amount of medicine necessary for the pH value of the water to be 12 or more is supplied to the boiler feed water W1. Thereby, at the time of execution of the can rest processing of the boiler 2, the boiler main body 21 is maintained in a state where the boiler water W2 having a full water storage amount is stored with water quality having a pH value of 12 or more.

  The medicine addition control unit 103 calculates the amount of medicine necessary for the pH value of the boiler water W2 to be 12, when the stored amount of the boiler water W2 is the full water storage amount. For example, the amount of medicine necessary for the pH value of the boiler water W2 having the full water storage amount to be 12 is calculated as follows.

In order to calculate the amount of the medicine necessary for the pH value of the boiler water W2 having the full water storage amount to be 12, the medicine addition control unit 103 stores the stored water amount V ₀ when the boiler water W2 is stopped when the boiler 2 stops combustion. And the pH value of the boiler water W2 converted from the electrical conductivity detected by the electrical conductivity sensor 42 when the combustion of the boiler 2 is stopped.

Specifically, the chemical addition control unit 103 calculates a stop storage amount V ₀ of the boiler water W2 from the water level detected by the water level detector 28 when the combustion of the boiler 2 is stopped. The chemical addition control unit 103 sets the electrical conductivity of the boiler water W2 detected by the electrical conductivity sensor 42 to a pH value based on the conversion table and conversion formula stored in the memory unit 110 when the combustion of the boiler 2 is stopped. Convert to.

The chemical addition control unit 103 uses the calculated water storage amount at stop V ₀ as V ₁ as a full water storage amount, C ₀ as the chemical concentration of boiler water W 2 when the boiler 2 stops combustion, and C ₁ as rest. when the drug concentration of boiler water W2 (full water reservoir capacity V ₁ boiler water W2 which is water in) in the can processing, so that the pH value of the boiler water W2 that is water at full capacity water volume V ₁ is the 12 or more Further, the supply amount X of the medicine is calculated by the following equation (2).
X = C ₁ · V ₁ −C ₀ · V ₀ (2)

For example, when a cleansing agent containing NaOH and / or KOH is used as a chemical, the chemical concentration C ₀ of the boiler water W2 at the time of combustion stop and the chemical concentration C ₁ of the boiler water W2 during the canning process are set. Can be expressed as:
Chemical concentration C ₀ of boiler water W2 when combustion is stopped = OH concentration of boiler water W2 when combustion is stopped / OH content ratio of chemical stock solution (3a)
The chemical concentration C ₁ of the boiler water W2 during the rest treatment = OH concentration of the boiler water W2 during the rest treatment / OH content of the chemical stock solution (3b)
Here, the OH concentration (that is, [OH ⁻ ]) of the boiler water W2 is obtained from the pH value of the boiler water W2 as follows.
pOH = −log ₁₀ [OH ⁻ ] = 14−pH (4)
Therefore, the chemical concentration of boiler water W2 at the time of combustion stoppage is obtained by calculating the OH concentration by converting the electrical conductivity of boiler water W2 at the time of combustion stoppage of boiler 2 to a pH value and dividing by the OH content of the drug stock solution. C ₀ is determined. In addition, since the OH concentration (lower limit) during the rest treatment is determined from the target pH value (≧ 12) during the rest treatment, the rest treatment can be performed by dividing this OH concentration by the OH content of the drug stock solution. drug concentration C ₁ of the boiler water W2 in is determined.

According to the above equation (2), level of drug concentration C ₀ of the boiler water W2 during combustion stop of the boiler 2, or with or without dilution of the boiler water W2 with steam condensate, Kyukan processing of the boiler 2 At the time of execution, it is possible to calculate the supply amount X of the medicine that can make the pH value of the boiler water W2 12 or more.

  The memory unit 110 stores a control program for operating the boiler system 1 of the present embodiment, predetermined parameters, various tables, and the like. In the present embodiment, the memory unit 110, for example, the detected water level value when the boiler 2 stops combustion, the detected water level value when the boiler 2 cools, and the electrical conductivity of the boiler water W2 when the boiler 2 stops burning. Memorize etc. In addition, the memory unit 110 stores a data table and a conversion formula for converting the electrical conductivity of the boiler water W2 detected by the electrical conductivity sensor 42 into a pH value. Further, the memory unit 110 stores the amount of water stored in the boiler water W2 corresponding to the detected water level value of the full water storage amount of the boiler water W2 and the amount of water stored during cooling of the boiler water W2 corresponding to the detected water level value when the boiler body 21 is cooled. Memorize etc. In addition, the memory unit 110 stores a calculation formula for calculating the addition amount of a chemical necessary for the pH value of the boiler water W2 of the full water storage amount to be 12 or more.

  Next, with reference to FIG. 1, operation | movement of the boiler system 1 of this embodiment is demonstrated easily. First, the boiler feed water W1 is supplied from a supply source (not shown) to the feed water tank 5. At this time, the boiler feed water W <b> 1 supplied from the supply source is softened water after the hardness component is removed by the hard water softening device 3. And the softened water produced | generated by the hard water softening device 3 is stored in the feed water tank 5 as boiler feed water W1. Here, the fuel supply valve 92 and the blow valve 93 are closed.

  Next, by operating the feed water pump 6, the boiler feed water W1 (softened water) stored in the feed water tank 5 is sent out toward the lower header 24 of the boiler body 21 through the feed water line L1. And the boiler feed water W1 supplied to the boiler 2 is stored in the lower header 24 and each water pipe 22 as boiler water W2.

  The feed water pump 6 supplies the boiler feed water W <b> 1 to the boiler body 21 so that the amount of the boiler water W <b> 2 becomes a preset start-up water storage amount when the boiler 2 is started. Boiler feed water W1 supplied to the boiler body 21 is stored as boiler water W2 in the lower header 24 and each water pipe 22. When the boiler feed water W1 is supplied to the lower header 24 and each water pipe 22, the chemical addition controller 103 causes the boiler feed water so that the water quality of the boiler water W2 becomes a corrosion-suppressing water quality that can suppress the corrosion of the boiler body 21. The medicine adding device 81 is controlled so as to supply the medicine corresponding to W1.

  Next, the fuel is supplied to the burner 27 by switching the fuel supply valve 92 from the closed state to the open state. When the burner 27 is ignited, the burner 27 starts combustion.

  The boiler water W2 stored in the lower header 24 and each water pipe 22 rises inside each water pipe 22 while being heated by the burner 27 through the water pipe wall, and then becomes wet steam SM1. And the wet steam SM1 produced | generated inside each water pipe 22 is collected by the upper header 23, and is introduce | transduced into the steam-water separator 7 via the steam extraction line L4.

  The wet steam SM1 introduced into the steam separator 7 is separated into dry steam SM2 and separated water W4. The dry steam SM2 separated by the steam separator 7 is collected in the steam header 50 through the steam delivery line L5 by switching the steam check valve 95 from the closed state to the open state. The steam SM3 collected in the steam header 50 is supplied to a steam using device (not shown). The separated water W4 separated by the steam separator 7 is returned to the lower header 24 through the precipitation line L6.

In the boiler 2 operated in this way, a can resting process may be executed in which the operation of the boiler 2 is stopped for a long period (for example, one week or more).
Next, the operation | movement of the can rest process in the boiler 2 of this embodiment is demonstrated. FIG. 3 is a flowchart showing a processing procedure at the time of execution of a can resting process in the boiler 2 of the first embodiment.

  As shown in FIG. 3, in step ST <b> 1, when the boiler rest process of the boiler 2 is executed, the control device 10 stops the operation of the boiler 2 through an instruction from the operator. Here, when the operation of the boiler 2 is stopped, for example, as described above, the steam inside the boiler body 21 and the steam separator 7 is condensed and the boiler water W2 is increased.

In step ST2, the chemical addition control unit 103 stores the detected water level value of the boiler water W2 detected by the water level detector 28 in the memory unit 110 when the combustion of the boiler 2 is stopped. The chemical addition control unit 103 reads the detected water level value of the boiler water W2 when the combustion of the boiler 2 is stopped, which is stored in step ST2, from the memory unit 110, and based on this water level value, the stored water amount V when the boiler water W2 is stopped. ₀ is calculated. The memory unit 110, the detection level value and water content of the relationship of the boiler water W2 is stored in advance, the agent addition control unit 103 can calculate the stop-time water quantity V ₀ based on this relationship.

  In step ST <b> 3, the chemical addition control unit 103 stores the electrical conductivity of the boiler water W <b> 2 detected by the electrical conductivity sensor 42 in the memory unit 110 when the combustion of the boiler 2 is stopped. The chemical addition control unit 103 reads out the electrical conductivity value of the boiler water W2 when the combustion of the boiler 2 is stopped, which is stored in step ST3, from the memory unit 110, and converts this electrical conductivity value into the pH value of the boiler water W2. . In the memory unit 110, the relationship between the electrical conductivity value of the boiler water W2 and the pH value is stored in advance as a data table or a conversion formula, and the chemical addition control unit 103 performs the electrical The conductivity can be converted into a pH value.

  In step ST4, the vapor pressure determination unit 102 determines whether or not the vapor pressure inside the boiler body 21 measured by the vapor pressure measurement unit 29 has become a predetermined pressure value or less. The predetermined pressure value is, for example, 0.03 MPa. When the pressure is equal to or lower than the predetermined pressure value, it can be considered that the inside of the boiler body 21 has been cooled. During the cooling of the boiler body 21, the steam becomes condensed water, and the boiler body 21 stores the amount of boiler water W <b> 2 during cooling. If it is determined that the vapor pressure inside the boiler body 21 is equal to or lower than the predetermined pressure value (YES), the process proceeds to step ST5. On the other hand, when it is determined that the vapor pressure inside the boiler body 21 is not equal to or lower than the predetermined pressure value (NO), the process returns to step ST4.

  In step ST <b> 5, the chemical addition control unit 103 stores the detected water level value at the time of cooling the boiler water W <b> 2 when the boiler body 21 is cooled when the vapor pressure inside the boiler body 21 is equal to or lower than a predetermined pressure value. Remember me.

In step ST6, the agent addition control unit 103 reads out the detection level value for the boiler water W2 when the boiler 2 the cooling from the memory unit 110, based on the water level value, calculating a cooling time of water storage amount V ₂ of the boiler water W2 To do. Then, the boiler water W2 becomes the full water storage amount V ₁ by the above formula (1) [forced water supply amount V _X = full water storage amount V ₁ −cooling water storage amount V ₂ ], and is supplied to the boiler body 21. A forced water supply amount V _X of the boiler water supply W1 is calculated.

In step ST7, the medicine addition control unit 103 calculates a medicine supply amount X based on the stopped water storage amount V ₀ calculated in step ST2 and the pH value converted in step ST3. Specifically, when the V ₁ and full water reservoir capacity, the C ₀ and the drug concentration in the boiler water W2 at stop burning, a drug concentration of boiler water W2 in Kyukan processing C _1, full water reservoir capacity the supply amount X of the drug required to the pH value of V ₁ boiler water W2 that is water in the 12 or more, is calculated by the above equation (2) to (4).

In step ST8, the boiler body 21, at the time of execution of Kyukan processing of the boiler 2, such that the predetermined full level water volume of the boiler water W2 in the water storage amount V _1, forced water calculated in step ST6 boiler feed water W1 quantity _{V X} is supplied. At the same time, the agent addition control unit 103, during execution of Kyukan processing of the boiler 2, pH value of the boiler water W2 that is water in the full-water water volume V ₁ is calculated at step ST7 required to be 12 or more The medicine supply device 81 executes a medicine supply process so that the supply amount X of medicine is added.

Typically, the agent addition control unit 103, the agent supply amount X as dispensed flow rate proportional agent, controls the medicated device 81 relative to the boiler feedwater W1 forced water supply amount V _X. And the process of this flowchart is complete | finished. And the boiler 2 is preserve | saved when the pH value of the boiler water W2 stored by the full water storage amount is 12 or more, and is in a full water state. As a result, in the boiler 2 according to this embodiment, the corrosion of the boiler body 21 is suppressed during the can resting process.

  In addition, while the can rest process of the boiler 2 is being executed, the can rest process is canceled (the use of the boiler body 21 is released and the use of the boiler body 21 is started), and the water is stored in the full water storage amount. For example, the boiler water W2 that has been used is replaced periodically (for example, every two months). In this case, the boiler 2 forcibly drains all of the boiler water W2 stored in the full water storage amount and supplies new boiler feed water W1 up to the full water storage amount. The amount of chemical | medical agent required in order to make the pH value of the boiler water W2 stored in quantity into 12 or more is supplied. The boiler 2 can automate such regular replacement of the boiler water W2.

Next, in the boiler 2 of 1st Embodiment, the cancellation | release method of the can process after execution of a can process is demonstrated.
When canceling the can resting process of the boiler 2 (releasing the use of the boiler main body 21 and starting the use of the boiler main body 21), the water level of the boiler water W2 stored in the full water storage amount is changed to the boiler water. The partial blow process of the boiler water W2 is executed so as to lower the water level to the start-up level without executing the full blow process of W2. And the combustion of the burner 27 is started in the state in which the boiler water W2 is stored up to the water level at startup. As a result, the boiler water W2 stored during the can resting process is boiled to generate the wet steam SM1, and supply of steam to the steam using device (not shown) is started via the steam header 50.

  Here, the drug added at the time of execution of the rest process is the same type of drug as that used during normal operation. Therefore, it is possible to quickly start the boiler 2 and generate steam by using the boiler water W2 stored during the resting process. As described above, since steam can be generated without executing the entire blow process of the boiler water W2, it is possible to shorten the time until the supply of steam is started when the can-can process is canceled.

According to the boiler 2 which concerns on 1st Embodiment mentioned above, the following effects are acquired, for example.
The boiler 2 in the present embodiment is a boiler 2 in which a can resting process is executed, and a water level detector 28 that detects the water level of the boiler water W2 when the combustion of the boiler 2 is stopped, and a boiler when the combustion of the boiler 2 is stopped. The electrical conductivity sensor 42 that indirectly detects the pH value of the water W2 and the amount of water of the boiler water W2 at the time of the can resting process of the boiler 2 become a preset full water storage amount (set water storage amount). When the boiler feed water W1 is supplied to the boiler main body 21, the drug supply device 81 capable of executing the chemical supply process for supplying the chemical to the boiler water supply W1, and the boiler 2 can-rest process, the boiler 2 Based on the detected water level value and the detected pH value of the boiler water W2 when the combustion is stopped, the amount of medicine necessary for the pH value of the boiler water W2 stored in the full water storage amount (set water storage amount) to be 12 or more So they are supplied to the boiler feedwater W1, it comprises an agent addition control unit 103 to execute the medicine supply process in the medicated device 81, the.

  Therefore, in the boiler 2 in which the can resting process is executed, the pH value of the boiler water W2 stored in the boiler main body 21 with the full water storage amount is 12 or more. Thereby, the corrosion of the boiler main body 21 can be suppressed at the time of the can rest processing of the boiler 2.

  Moreover, the chemical | medical agent added at the time of execution of a can resting process is the same kind of chemical | medical agent as the chemical | medical agent used during normal driving | operation. Therefore, the boiler water W2 can be started up quickly by simply performing the partial blow processing of the boiler water W2 and reducing the boiler water W2 to the starting storage amount without executing the full blow processing of the boiler water W2. Can be generated. Therefore, the time until the supply of steam can be shortened when canceling the can resting process can be shortened. And since the chemical | medical agent added during execution of a can rest process is the chemical | medical agent of the same kind as the chemical | medical agent used during normal driving | operating, even if the boiler 2 is started as it is, ensuring the safety | security of steam quality. Can do.

(Second Embodiment)
Next, a boiler system 1A according to a second embodiment of the present invention will be described. FIG. 2 is a diagram showing an outline of a boiler system 1A according to the second embodiment of the present invention.
In the second embodiment, differences from the first embodiment will be mainly described. For this reason, the same code | symbol is attached | subjected about the same (or equivalent) structure as 1st Embodiment, and detailed description is abbreviate | omitted. The description of the first embodiment is appropriately applied to points that are not particularly described in the second embodiment. In the second embodiment, the boiler water W2 having the “full water storage amount” is stored in the boiler body 21 in the first embodiment, while the boiler water having the “starting water storage amount” is stored. Regarding the point that W2 is stored in the boiler body 21, the boiler system 1 of the first embodiment does not include the nitrogen cylinder, the point that the nitrogen system 11 is provided, and the configuration around the nitrogen cylinder 11 is the first. Mainly different from the boiler system 1 of the embodiment.

  A boiler system 1A according to the second embodiment includes a nitrogen cylinder 11, a nitrogen gas supply line L11, and an open air line L12 in addition to the configuration of the boiler system 1 according to the first embodiment. The boiler system 1A according to the second embodiment includes a nitrogen gas supply valve 61, a nitrogen gas pressure adjustment valve 62, and an atmosphere release valve 63.

  The nitrogen cylinder 11 contains nitrogen gas G inside. The nitrogen gas supply line L <b> 11 is a line that supplies the nitrogen gas G stored in the nitrogen cylinder 11 to the boiler body 21. The upstream end of the nitrogen gas supply line L <b> 11 is connected to the nitrogen cylinder 11. The downstream end of the nitrogen gas supply line L11 is connected to the upper end of the upper header 23 of the boiler body 21. A nitrogen gas supply valve 61 is provided in the nitrogen gas supply line L11. The nitrogen gas supply valve 61 can open and close the nitrogen gas supply line L11. In the present embodiment, the opening and closing of the nitrogen gas supply valve 61 is controlled by a drive signal from the control device 10.

  A nitrogen gas pressure adjusting valve 62 is provided between the nitrogen gas supply valve 61 and the nitrogen cylinder 11. The nitrogen gas pressure adjustment valve 62 is a valve that adjusts the pressure of the nitrogen gas G supplied from the nitrogen cylinder 11 to the boiler body 21.

  The atmosphere release line L12 is a line that opens the interior of the boiler body 21 to the atmosphere via the steam / water separator 7. The upstream end of the atmosphere release line L12 is connected to a connection J7 between the steam separator 7 and the steam check valve 95 in the steam delivery line L5. The downstream end of the atmosphere release line L12 is open to the atmosphere. An air release valve 63 is provided in the air release line L12. The atmosphere release valve 63 can open and close the atmosphere release line L12. Opening and closing of the air release valve 63 is controlled by a drive signal from the control device 10.

In the second embodiment, the feed water pump 6 is configured so that the boiler water W1 is set so that the amount of the boiler water W2 becomes the startup water storage amount (preset water storage amount set in advance) when the boiler rest process of the boiler 2 is executed. Is supplied to the boiler body 21.
The startup water storage amount is the storage amount of boiler water W2 stored in the boiler body 21 when the boiler 2 is started. Specifically, as shown in FIG. 4, the stored water amount at the time of start-up means that the boiler water W <b> 2 is stored up to a position on the upper side of the water pipe 22 while leaving a space above the plurality of water pipes 22 in the boiler body 21. Is the amount of water stored. In the case where the boiler water W <b> 2 of the startup water storage amount is stored in the boiler body 21, a gas phase portion is formed in the space above the boiler water W <b> 2 (the upper portion of the water pipe 22 and the upper header 23).

  Moreover, in 2nd Embodiment, the chemical | medical agent addition control part 103 starts based on the detected water level value and detected pH value of the boiler water W2 at the time of the combustion stop of the boiler 2 at the time of the boiler rest process of the boiler 2 being performed. The medicine supply process is executed in the medicine addition device 81 so that an amount of medicine necessary for the pH value of the boiler water W2 stored in the hourly water storage amount to be 12 or more is supplied to the boiler feed water W1. Thereby, at the time of execution of the can rest process of the boiler 2, the boiler main body 21 is maintained in a state in which the boiler water W2 of the starting storage amount is stored with water quality having a pH value of 12 or more.

  Other configurations and operations in the second embodiment are the same as those in the case where “full water storage amount” in the first embodiment is replaced with “start-up water storage amount”. Therefore, the other description of the second embodiment is the same as the description in which “full water storage amount” in the description of the first embodiment is replaced with “start-up water storage amount”, and thus the description of the first embodiment is cited. The description is omitted or simplified.

  In 2nd Embodiment, the boiler water supply W1 is supplied to the boiler main body 21 to the storage amount at the time of starting. Therefore, a gas phase part is formed in the upper space of the boiler water W2. In the second embodiment, nitrogen gas G is sealed in the gas phase portion of the upper part of the boiler water W2 that has been stored up to the startup storage amount inside the boiler body 21.

A method for enclosing the nitrogen gas G in the gas phase inside the boiler body 21 will be described.
First, through an instruction from the operator to start the can resting process, the control device 10 adds the boiler water W2 to the startup water storage amount while adding a chemical to the boiler feed water W1 so that the pH value of the boiler water W2 is 12 or more. Store. Next, as shown in FIG. 4, the control device 10 controls the nitrogen gas supply valve 61 to an open state in a state where the nitrogen gas pressure is adjusted to 0.02 MPa by the nitrogen gas pressure adjustment valve 62. Thereafter, the control device 10 controls the atmosphere release valve 63 to an open state. Accordingly, the gas in the gas phase portion of the boiler body 21 is replaced with the nitrogen gas G while pushing out the gas in the gas phase portion of the boiler body 21 from the atmosphere opening line L12 due to the pressure difference between the pressure of the nitrogen gas G and the atmospheric pressure. The control device 10 controls the air release valve 63 and the nitrogen gas supply valve 61 to be closed after a predetermined time has elapsed. With the above operation, the nitrogen gas G is sealed in the gas phase portion in the boiler body 21.

  Thereby, inside the boiler main body 21, while the boiler water W2 with a pH value of 12 or more is stored up to the amount of stored water at startup, nitrogen gas G is sealed in the gas phase portion. Therefore, the corrosion of the boiler main body 21 can be suppressed when the boiler rest process of the boiler 2 is executed. In this state, a can resting process in which the use of the boiler body 21 is suspended is performed.

  In addition, during execution of the can rest processing of the boiler 2, until the can rest processing is canceled, the boiler water W2 stored in the start-up water storage amount is periodically replaced (for example, every two months). It is done. Simultaneously with the replacement of the boiler water W2 stored in the startup storage amount, the nitrogen gas G is also replaced at the same time.

Next, in the boiler 2 of 2nd Embodiment, the cancellation | release method of the can rest process after execution of a can rest process is demonstrated.
When canceling the can resting process of the boiler 2, the combustion of the burner 27 is performed in the same state as when the can resting process in which the boiler water W2 is stored in the stored water amount at the start and the nitrogen gas G is enclosed. To start. As a result, the boiler water W2 stored during the can resting process is boiled to generate the wet steam SM1, and supply of steam to the steam using device (not shown) is started via the steam header 50.

  Here, the drug added during the rest process is the same type of drug as that used during normal operation. Further, since the nitrogen gas G is harmless and has no danger of ignition or the like, there is no problem even if it is distributed to consumers without performing the operation of discharging the nitrogen gas G. Therefore, it is possible to quickly start the boiler 2 and generate steam by using the boiler water W2 stored during the resting process. In this way, it is possible to generate steam without performing the entire blow process of the boiler water W2 and without performing the operation of discharging the nitrogen gas G. Therefore, the time until the supply of steam can be shortened when canceling the can resting process can be shortened.

According to the boiler 2 which concerns on 2nd Embodiment mentioned above, in addition to the effect similar to the said 1st Embodiment, the following effects are acquired, for example.
In this embodiment, when the boiler water W <b> 2 of the startup water storage amount is stored in the boiler body 21 during the can resting process of the boiler 2, up to the startup storage amount in the boiler body 21. Nitrogen gas G is sealed in the space above the stored boiler water W2. For this reason, the boiler body 21 is sealed while the nitrogen gas G is sealed in the boiler body 21 and the boiler water W2 having a pH value of 12 or more is stored, so that the corrosion of the boiler body 21 can be suppressed. it can.

  Furthermore, it is possible to quickly start the boiler 2 and generate steam without performing the entire blow process of the boiler water W2 and without performing the operation of discharging the nitrogen gas G. Therefore, the time until the supply of steam can be shortened when canceling the can resting process can be shortened. And the chemical | medical agent added during execution of a rest process is the same kind of chemical | medical agent as the chemical | medical agent used during a normal driving | operation. Nitrogen gas G, which is harmless and has no danger of ignition or the like, is enclosed in the space above the boiler water W2 that has been stored up to the amount of water stored at startup. Therefore, even if the boiler 2 is started in the state as it is when the can resting process is executed, the safety of the steam quality can be ensured.

The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and can be implemented in various forms.
For example, in the above-described embodiment, the chemical addition device 81 is configured to add chemicals to the boiler feed water W1 between the feed water tank 5 and the feed water pump 6 in the feed water line L1, but is not limited thereto. For example, the chemical addition device 81 may be configured to add chemicals to the boiler feed water W1 between the feed water pump 6 and the boiler 2 in the feed water line L1, or to the boiler feed water W1 stored in the feed water tank 5. You may comprise so that a chemical | medical agent may be added.

Moreover, in the said embodiment, although the pH value of boiler water W2 was indirectly detected in conversion from electrical conductivity, it is not restrict | limited to this. For example, the pH value of the boiler water W2 may be directly detected by a pH value sensor, or the pH value of the boiler water W2 is indirectly detected by converting the acid consumption (pH 8.3) of the boiler water W2. May be. The acid consumption (pH 8.3) is defined in JIS K0101, and the equivalent number of acid necessary for lowering the pH value of boiler water W2 to pH 8.3 is converted to CaCO ₃ (calcium carbonate). It is also called P alkalinity. Since the pH value is correlated with the acid consumption (pH 8.3), it can be converted from the acid consumption (pH 8.3).

2 Boiler 6 Feed water pump (Boiler feed water supply means)
21 Boiler body 28 Water level detector (water level detection means)
42 Electric conductivity sensor (pH value detection means)
81 Drug addition device (medicine supply means)
103 Drug Addition Control Unit (Drug Supply Control Unit)
W1 Boiler water supply W2 Boiler water

Claims (8)

A boiler in which a can resting process for stopping use of a boiler body in which boiler water is stored as boiler water is executed,
A water level detecting means capable of continuously detecting the water level of the boiler water and detecting the water level of the boiler water when the combustion of the boiler is stopped;
PH value detection means for directly or indirectly detecting the pH value of boiler water at the time of combustion stop of the boiler;
Boiler water supply means for supplying boiler water to the boiler body so that the amount of boiler water is a preset water storage amount when the boiler can-can process is performed;
A medicine supply means capable of executing a medicine supply process for supplying medicine to the boiler feed water;
At the time of execution of the boiler rest process, the pH value of the boiler water stored in the set water storage amount becomes 12 or more based on the detected water level value and the detected pH value of the boiler water when the combustion of the boiler is stopped. A medicine supply control unit that causes the medicine supply means to execute the medicine supply process so that a necessary amount of medicine is supplied to the boiler feed water;
Boiler equipped with. The set water storage amount is a full water storage amount when the boiler body is full, or a startup water storage amount when starting the boiler,
The boiler according to claim 1. In the case where the set water storage amount is the starting water storage amount, nitrogen gas is enclosed in the space above the boiler water stored up to the starting water storage amount in the boiler body.
The boiler according to claim 2. The detected pH value is a pH value that directly detects the pH value of boiler water by a pH value sensor, a pH value that is indirectly detected by conversion from the electrical conductivity of boiler water, or the acid consumption of boiler water. Including the pH value detected indirectly in terms of the amount (pH 8.3),
The boiler in any one of Claim 1 to 3. A boiler can processing method for executing a can processing for stopping use of a boiler body in which boiler water is stored as boiler water.
The boiler water supply is supplied to the boiler body so that the amount of boiler water becomes a preset water storage amount at the time of the boiler resting process, and the detected water level of the boiler water when the boiler combustion is stopped. Based on the value and the detected pH value, the chemical supply process is executed so that a necessary amount of chemical is supplied to the boiler feed water so that the pH value of the boiler water of the set water storage amount becomes 12 or more.
A boiler can disposal method. The set water storage amount is a full water storage amount when the boiler body is full, or a startup water storage amount when starting the boiler,
The boiler can treatment method according to claim 5. In the case where the set water storage amount is the starting water storage amount, nitrogen gas is enclosed in the space above the boiler water stored up to the starting water storage amount in the boiler body.
A boiler can treatment method according to claim 6. The detected pH value is a pH value that directly detects the pH value of boiler water by a pH value sensor, a pH value that is indirectly detected by conversion from the electrical conductivity of boiler water, or the acid consumption of boiler water. Including the pH value detected indirectly in terms of the amount (pH 8.3),
A boiler can treatment method according to any one of claims 5 to 7.

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