JP2007263470A - Operation method of boiler apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently and stably operate a boiler apparatus while securing the quality of steam. <P>SOLUTION: This operation method of the boiler apparatus includes: a measuring process H1 of measuring the quantity of impurity contained in steam S2 supplied from the boiler apparatus A always or at intervals of fixed time; and a changing and operating process of changing the operating condition to decrease the quantity of impurity until the quantity of impurity in supply steam S2 is decreased within a preset value when the quantity of impurity measured in the measuring process H1 exceeds a preset value predetermined about the impurity. Since the quality against impurity in the supply steam S2 is secured, and also changing and operation is performed by ordinary operation technique, the boiler apparatus A is operated efficiently and stably. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an operation method of a boiler device, and more particularly to an operation method of a boiler device that performs appropriate operation of a boiler device according to the result while monitoring the quality of steam.

  Impurities in the boiler feedwater remain in the boiler water and accumulate in it, but some are carried out of the boiler device along with the steam. Therefore, the impurities in the boiler feed water cause scale and cause of corrosion not only in the piping and heating pipes in the boiler apparatus but also in the heat exchanger and piping outside the boiler apparatus. Similarly, the dissolved oxygen in the boiler feed water not only promotes corrosion inside the boiler device, but also promotes corrosion outside the boiler device via steam. Also, regarding the pH value of boiler feed water and the like, if this deviates from a predetermined range, similarly, corrosion easily occurs inside and outside the boiler device.

  For this reason, the boiler apparatus blows down boiler water or injects chemicals necessary for boiler water supply or the like to prevent corrosion and scale generation at various locations.

  However, in the conventional boiler device, the boiler water supply in the boiler device and the water management related to the boiler water are sufficiently performed. However, the quality control of the steam itself supplied from the boiler device to other facilities is performed by the boiler water supply and the boiler water. It was dependent on water management and could not be said to have been done sufficiently. Therefore, even if corrosion and scale generation on piping and heating pipes in the boiler device are prevented, it cannot be said that corrosion and scale generation on heat exchangers and piping outside the boiler device are necessarily prevented reliably. It was.

  In addition, in food factories and pharmaceutical factories, the quality of steam related to impurities is regarded as important in consideration of the possibility of steam contamination or vapor contamination in the handling items. In such factories, the quality of steam is directly monitored. That is not done. For this reason, in such factories, boiler chemicals such as oxygen scavengers are handled by using highly safe chemicals or by not using boiler chemicals at all, and the operation of boiler equipment is efficient and stable. It could not be said that it was made.

  This invention aims at providing the operating method of the boiler apparatus which can prevent reliably generation | occurrence | production of the corrosion resulting from a vapor | steam, and a scale in view of the above point.

  Another object of the present invention is to provide a method for operating a boiler device that can efficiently and stably operate the boiler device while ensuring the quality of steam.

  According to the first aspect of the present invention, there is provided a measurement step of measuring the amount of impurities contained in the steam supplied from the boiler device at regular or regular intervals, and the amount of the impurities measured in the measurement step. When the predetermined set value for this impurity is exceeded, the operating condition is changed so as to decrease the impurity amount until the amount of the impurity in the supply steam decreases within the set value. And a change operation step of operating the boiler device.

  In the present invention, when the amount of impurities in the supply steam exceeds the set value, the operation of the boiler device is changed to an operation that reduces the amount of impurities within the set value. For this reason, in this invention, the amount of impurities in the supply steam is suppressed within a set value, and the quality of the supply steam can be ensured with respect to this impurity. In this case, since the operation for reducing the amount of impurities in the supply steam can be performed by a general operation method of the boiler device, the operation of the boiler device can also be performed efficiently and stably. Further, in this invention, when the amount of impurities in the supply steam decreases from the set value, the operation of the boiler device is returned to the normal operation before the change, so that the amount of impurities in the supply steam is excessively reduced. There is nothing. The change operation itself or operation switching may be performed automatically using a control device, or may be performed manually by an operator.

  According to a second aspect of the present invention, in the case of the first aspect of the present invention, the impurity is total organic carbon and / or a scale-causing substance.

  In this invention, when the impurity is total organic carbon, when the total organic carbon amount in the supply steam exceeds the set value, the operation of the boiler device is changed to an operation that reduces the total organic carbon amount. The quality of the supply steam is ensured with respect to the total organic carbon content. In the present invention, even when the impurity is a scale-causing substance, the same operation is performed as when the impurity is total organic carbon, and the quality of the supply steam is ensured with respect to the amount of the scale-causing substance in the supply steam. The

  According to a third aspect of the present invention, there is provided a measuring step for measuring the electrical conductivity of condensed water condensed from the steam supplied from the boiler device at regular or regular time intervals, and the electric power measured in the measuring step. If the conductivity value exceeds a predetermined set value, the conductivity value is set to the set value until the conductivity value of the condensed water of the supply steam decreases within the set value. The operation condition is changed so as to decrease within a range, and the operation of the boiler device is changed, and a change operation step is included.

  In this invention, when the electric conductivity value of the condensed water of the supply steam exceeds the set value, the operation of the boiler device is changed to an operation that decreases the electric conductivity value, and the causative substance that causes the electric conductivity, that is, The amount of inorganic impurities is suppressed, and the quality of the supply steam is ensured with respect to the inorganic impurities. Further, in this invention, when the electric conductivity value of the condensate water for supply steam decreases from the set value, the operation of the boiler device is returned to the normal operation before the change, so the electric conductivity of the condensate water for supply steam The value will not be reduced excessively. Note that the change operation itself or operation switching may be performed automatically using a control device, or may be performed manually by an operator.

  According to a fourth aspect of the present invention, in the case of the third aspect of the present invention, the change of the operating condition in the changed operation step is to increase the blow-down rate of boiler water.

  In the invention according to claim 5 of the present invention, the measurement step of measuring the amount of dissolved oxygen in the steam supplied from the boiler device at regular or regular time intervals, and the amount of dissolved oxygen measured in the measurement step are If the predetermined set value is exceeded, the operating conditions are changed so as to decrease the dissolved oxygen amount until the dissolved oxygen amount in the supply steam decreases within the set value, and the boiler And a change operation step for operating the apparatus.

  In this invention, when the amount of dissolved oxygen in the supply steam exceeds the set value, the operation of the boiler device is changed to an operation for reducing the amount of dissolved oxygen, and the amount of dissolved oxygen is suppressed. Steam quality is ensured. In this invention, when the amount of dissolved oxygen in the supply steam decreases from the set value, the operation of the boiler device is returned to the normal operation before the change, so the amount of dissolved oxygen in the supply steam is excessively reduced. There is no end. Note that the change operation itself or operation switching may be performed automatically using a control device, or may be performed manually by an operator.

  According to a sixth aspect of the present invention, in the case of the fifth aspect of the present invention, the change of the operation condition in the change operation step is to increase the temperature of boiler feed water.

  According to a seventh aspect of the present invention, there is provided a measuring step for measuring the pH of the steam supplied from the boiler device at regular time intervals or a predetermined setting range in which the pH value measured in the measuring step is predetermined. In the case of deviating from the above, until the pH value of the supply steam falls within the set range, the operating conditions are changed so that the pH value falls within the set range, and the boiler apparatus is operated. And a modified operation process.

In the present invention, when the pH value of the supply steam deviates from the set range, the operation of the boiler device is changed to an operation that keeps the pH value within the set range, and the pH value is adjusted within the set range,
With this pH value, the quality of the supply steam is ensured. Note that the change operation itself or operation switching may be performed automatically using a control device, or may be performed manually by an operator.

  According to the first aspect of the present invention, since the amount of impurities in the supply steam is not increased from the set value, the quality of the steam with respect to the amount of impurities is secured, and the quality of the steam with respect to the amount of impurities. Even in food factories and pharmaceutical factories where importance is attached to the steam, steam from such boiler devices can be easily used. Therefore, in such a factory, it is possible to operate the boiler device without performing a special operation, and an efficient and stable boiler operation can be achieved.

  In addition, according to the present invention, the amount of impurities in the supply steam is not increased from the set value, so that it is possible to reliably prevent the adverse effects caused by the impurities on the heat exchanger, piping, etc. in which this steam is used. When the steam condensate is used as boiler feed water, the amount of impurities in the boiler feed water can be reduced.

  According to invention of Claim 2 of this invention, the quantity of the total organic carbon and scale causative substance in supply steam can be reduced, and the quality of supply steam regarding these can be ensured. Further, according to the present invention, the amount of total organic carbon and scale causative substances that cause corrosion in the supply steam can be reduced, and as a result, heat exchangers, piping, and the like in which this steam is used It is possible to reliably prevent corrosion and scale adhesion that occur on the surface.

  According to the third aspect of the present invention, since the amount of inorganic impurities in the supply steam that causes electrical conductivity is not increased from the set value, the quality of the steam related to the inorganic impurities is not increased. Therefore, the steam from the boiler apparatus can also be used in food factories, pharmaceutical factories, and the like where the quality of the steam is important with respect to such inorganic impurities. Therefore, in such a factory, it is possible to operate the boiler device without performing a special operation, and an efficient and stable boiler operation can be achieved. Further, according to the present invention, since the inorganic impurities include scale-causing substances, the same effects as those of the invention described in claim 2 can be obtained with respect to prevention of scale adhesion.

  According to the fourth aspect of the present invention, causative substances that cause electrical conductivity in the supply vapor, that is, inorganic impurities, can be reduced relatively easily.

  According to the invention described in claim 5 of the present invention, the amount of dissolved oxygen in the supply steam is not increased more than the set value. Therefore, due to the dissolved oxygen, the heat exchanger in which this steam is used, Corrosion that occurs in pipes can be reliably prevented. Further, according to the present invention, when this steam condensate is used as boiler feed water, the amount of dissolved oxygen in the boiler feed water can be reduced, and the water quality deterioration due to corrosion can be suppressed, so that this condensate is effectively used. It can be used as boiler feed water.

  According to the sixth aspect of the present invention, the amount of dissolved oxygen in the supply steam can be reduced relatively easily.

  According to the invention described in claim 7 of the present invention, the pH value in the supply steam can be kept within the set range. Therefore, due to the pH value, the heat exchanger or piping or the like in which this steam is used. Corrosion that occurs can be surely prevented, and when this steam condensate is used as boiler feedwater, this condensate can be effectively used as boiler feedwater as much as water quality deterioration due to corrosion can be suppressed. .

Embodiments of the present invention will be described below with reference to the drawings.
Embodiment 1. FIG.
FIG. 1 shows a main equipment arrangement around a boiler apparatus according to an embodiment of the present invention.

  As shown by a chain line in FIG. 1, the boiler apparatus A includes a water supply tank 10, a boiler 20 as a steam generator, a steam header 30, a chemical liquid injector 40, a blowdown device 50, and a steam quality control device. 60. In addition, as shown in FIG. 1, a raw water tank 100 and a steam utilization facility 110 are provided outside the boiler device A as facilities outside the boiler device.

  Here, the range of the boiler apparatus A is determined from the viewpoint of ensuring the quality of supply steam. In the boiler apparatus A of the first embodiment, for example, the feed water tank 10 is equipment outside the boiler apparatus. May be. Moreover, although the boiler 20 presupposes a comparatively low pressure water tube boiler, a round boiler, a once-through boiler, and other special boilers may be sufficient, and a pressure may be any of a low pressure, a medium pressure, and a high pressure.

  The raw water W0 stored in the raw water tank 100 is treated with water if necessary, and then supplied to the water supply tank 10 through the pipe L1. The boiler feed water W1 in the feed water tank 10 is pressurized by a feed pump (not shown) and then supplied to the boiler 20 through the pipe L2. The steam S1 generated in the boiler 20 is superheated as necessary, and then sent to the steam header 30 provided at the boiler device outlet through the pipe L3. The supply steam S2 in the steam header 30 is supplied to a steam use facility such as a heat exchanger (only the steam use facility 110 is shown in this embodiment) through the pipes L10, L11, L12, and its condensate. Is recovered in the water supply tank 10 through the pipes L13, L14, L15.

  The chemical solution injection device 40 includes a chemical solution tank 41, a chemical injection pump 42, and a pipe L4 that connects these pipes L2. The chemical solution tank 41 is filled with a chemical solution in which an oxygen scavenger such as sodium sulfite or hydrazine is dissolved in water. The medicinal pump 42 is, for example, a plunger pump whose stroke can be adjusted, and injects the medicinal solution in the medicinal tank 41 into the boiler water supply line (in the pipe L2) through the pipe L4.

  The blow-down device 50 includes a flow rate adjusting valve 51, a blow-down tank 52, and a pipe L5 that connects these to the boiler 20 (specifically, the boiler body of the boiler 20). The boiler water W2 in the boiler 20 passes through the flow rate adjustment valve 51 and is continuously blown into the blow-down drum 52 by a certain amount, for example, and is divided into water and steam in the blow-down drum 52, and then the boiler device A Used or not used.

  The steam quality control device 60 analyzes the water quality of the condensed water W3 of the supply steam S2 (in this embodiment, total organic carbon (TOC) and electrical conductivity) and generates a predetermined signal. The steam quality control device 60 includes a cooler 61, a TOC meter 62 and an electrical conductivity meter 63 for water quality analysis, a pipe L7 for connecting the pressure gauge 31 of the steam header 30 and the cooler 61, and a pipe L7. It comprises a pipe L8 through which the condensed water W3 of the supply steam S2 cooled by the cooler 61 flows. The TOC meter 62 and the electrical conductivity meter 63 are connected to the pipe L8 and constantly measure the TOC value and the electrical conductivity value for the condensed water W3 of the supply steam S2.

Here, the measured TOC value indicates the amount of organic impurities in the steam, and since this TOC also causes corrosion of the metal member, if it is large, it comes into contact with the steam and its condensate. Causes corrosion on metal parts. The electrical conductivity value is a value indicating the amount of inorganic impurities in the vapor. Examples of the inorganic impurities include Ca ²⁺ , Mg ²⁺ , Fe ²⁺ , Na ⁺ , Cl ⁻ , SO ₄ ^2- and scale-causing substances such as SiO ₂ are included. Therefore, if the electrical conductivity value is large and there are many inorganic impurities, a scale is formed on the member in contact with the steam or its condensate.

  The TOC meter 62 is electrically connected to the chemical liquid injector 40 by wiring so that the stroke of the chemical injection pump 42 can be automatically controlled. The TOC meter 62 is provided with a controller 62a that causes the boiler apparatus A to perform a change operation in relation to the chemical liquid injector 40. When the measured TOC value in the supply steam S2 exceeds a predetermined set value (for example, 50 mS / m), the controller 63a is more than in the case of normal operation until the TOC value decreases within the set value. Then, the operation (change operation) is performed such that the stroke of the medicinal pump 42 is reduced by a predetermined amount, and the medicinal amount to the water supply line is reduced (or eliminated in some cases).

  The electrical conductivity meter 63 is electrically connected to the blow-down device 50 by wiring so that the opening degree of the flow rate adjustment valve 51 can be automatically controlled. The electrical conductivity meter 63 is provided with a controller 63 a that causes the boiler device A to perform a change operation in connection with the blow-down device 50. When the measured electrical conductivity value of the condensed water W3 of the supply steam S2 exceeds a predetermined set value (for example, 3 mS / m), the controller 63a decreases the electrical conductivity value within the set value. Until the normal operation, the opening of the flow rate adjustment valve 51 is increased by a predetermined amount, and the operation (change operation) is performed to increase the blow-down amount of the boiler water W2.

Next, an operation method of the boiler apparatus A will be described.
First, normal operation will be described. Here, the normal operation refers to a steady operation of the boiler apparatus A that is determined in advance according to the purpose of use, use conditions, and the like of the supply steam S2.

  The boiler feed water W1 in the feed water tank 10 is supplied to the boiler 20 by a feed water pump. Since a chemical solution having a deoxygenation effect is injected into the boiler feed water W1 by a certain amount by the chemical solution injection device 40, the boiler feed water W1. The oxygen concentration inside decreases. In this case, the pH value of the boiler feed water W1 is maintained at about 6 to 9 defined by regulations. Since the pH adjuster is initially administered to the boiler 20, the pH value of the boiler water W <b> 2 in the boiler 20 is also maintained at about 11 to 12 defined by regulations.

  Further, since a certain amount (for example, 3% of the normal boiler water supply amount) of boiler water W2 is continuously blown down from the can body of the boiler 20 by the blow-down device 50, it is brought in by the boiler water supply W1. The amount of impurities (organic impurities and inorganic impurities) in the boiler water W2 is kept relatively low. Therefore, in the can body (specifically, the steam drum) of the boiler 20, almost no carryover or the like occurs, and only the evaporated steam is sent to the steam header 30. The supply steam S2 exiting the steam header 30 is sent to the steam use facility 110 and used in a heat exchanger or the like of the steam use facility 110, and then returned to the condensate and collected in the feed water tank 10.

  The supply steam S2 in the steam header 30 is measured by the steam quality control device 60 for its TOC value and electrical conductivity value of the condensed water W3. These values are within the set values, and the TOC meter 62 and The controller 62a, 63a of the electrical conductivity meter 63 does not issue a signal for instructing the chemical liquid injector 40 or the blowdown device 50 to perform a change operation. Therefore, the quality of the supply steam S2 related to impurities is ensured appropriately, and corrosion and scale are hardly generated in the steam use facility 110 and the pipes L10 to L15.

  Next, the changing operation of the boiler apparatus A will be described. For example, the amount of steam used increases for a certain period of time, and during this time, when the load on the boiler device increases, the feed water flow rate from the feed water tank 10 to the boiler 20 increases. In this case, although the inorganic impurities brought in by the boiler feed water W1 increase, the amount of blowdown from the boiler 20 is constant, so this impurity is accumulated in the boiler 20 and the impurity concentration of the boiler water W2 increases. For this reason, a carryover or the like is likely to occur in the boiler 20, and a lot of boiler water W2 is mixed in the supply steam S2.

  In this case, since the electric conductivity meter 63 measures the electric conductivity value exceeding the set value, the controller 63a sends a signal to the blow-down device 50 to open the opening of the flow rate adjustment valve 51 larger than the current state, The amount of blowdown from the boiler 20 is increased. Then, the controller 63a continues this change operation until the electric conductivity value of the condensed water W3 of the supply steam S2 decreases from the set value. When the electric conductivity value of the condensed water W3 of the supply steam S2 decreases from the set value, the blow-down amount is returned to the original state, the change operation is terminated, and the operation of the boiler device A is returned to the previous normal operation.

  Further, for example, when the amount of the chemical liquid injected from the chemical liquid injector 40 into the boiler feed water W1 for some reason increases, the chemical liquid itself or a reaction product thereof is accumulated in the boiler 20 and the TOC value in the boiler water W2 increases. For this reason, organic impurities derived from the TOC are mixed into the supply steam S2 by, for example, carryover, and the TOC meter 62 measures the TOC value exceeding the set value. In this case, the controller 62a sends a signal to the chemical injection device 40 to reduce the stroke of the chemical injection pump 42 and reduce the chemical injection amount from the chemical injection device 40 to the boiler water supply line. Then, the controller 62a continues this change operation until the TOC value of the condensed water W3 of the supply steam S2 decreases from the set value, and when the TOC value of the condensed water W3 of the supply steam S2 decreases from the set value, This change operation is terminated, and the operation of the boiler device A is returned to the previous normal operation.

  Of course, the controller 62a of the TOC meter 62 and the controller 63a of the electrical conductivity meter 63 are simultaneously operated, and a change operation in which the operations of the chemical solution injector 40 and the blowdown device 50 are simultaneously changed may occur.

  FIG. 2 is a flowchart showing the operation method of the boiler device A in an easily understandable manner. That is, in the operation method of the boiler apparatus A, it is determined whether or not the measured value is equal to or less than a set value after the measurement process H1 for measuring the amount of impurities (organic or inorganic impurities) in the supply steam S2. A determination process H2 is provided, and after this determination process H2, a normal operation process H3 in which normal operation is performed if the measured value is equal to or less than the set value, and the boiler apparatus A is operated under the changed operation condition if the measured value exceeds the set value. And a change operation process H4 for driving the vehicle. Thereafter, the process returns to the measuring step H1, and the same steps are repeated thereafter.

  As described above, in the operation method of the boiler apparatus A, when the TOC value (organic impurity amount) or the electrical conductivity value (inorganic impurity amount) in the supply steam S2 exceeds the set value, the operation of the boiler apparatus is performed. However, since the operation is changed to reduce the amount of these impurities within the set value, the amount of organic impurities or the amount of inorganic impurities in the supply steam S2 or the total amount of impurities combined with these is set to the set value. The quality of the supply steam S2 can be ensured with respect to these impurities. Therefore, even in food factories and pharmaceutical factories where steam quality is important with respect to the amount of impurities, the steam from the boiler apparatus A that is operated can be easily used. It is no longer necessary to operate an inefficient boiler device using a special chemical solution having a high level or to operate an unstable device without using a chemical solution.

  Further, in the operation method of the boiler apparatus A, when the amount of each impurity in the supply steam S2 is decreased from the set value, the operation of the boiler apparatus is returned to the normal operation before the change, so that each of the supply steam S2 in the supply steam S2 The amount of impurities is not reduced excessively (more than necessary).

  Further, in the operation method of the boiler apparatus A, the amount of organic impurities in the supply steam S2 is not increased from the set value, so that the steam using equipment in which this steam is used due to the organic impurities. 110 and the pipes L10 to L15 can be reliably prevented from being corroded.

  Further, in the operation method of the boiler apparatus A, the amount of inorganic impurities in the supply steam S2 is not increased from the set value. Therefore, the use of steam in which this steam is used due to inorganic impurities. Scale formation occurring in the facility 110 and the pipes L10 to L15 can be reliably prevented, and an energy saving effect can be achieved by suppressing a decrease in heat exchange efficiency.

  Further, in the operation method of the boiler apparatus A, the amount of organic impurities and inorganic impurities in the supply steam S2 are not increased from the set values, respectively, so that the condensate of the supply steam S2 is purified. When this condensate is used as boiler feed water W1, the impurity concentration in boiler water W2 can be kept small. As a result, in this boiler apparatus A, the blow-down rate of the boiler water W2 can be kept low, a water saving effect can be obtained, and the carryover that occurs in the boiler 20 can be reduced, and the operation of the boiler 20 is stabilized accordingly. Can be made.

  In addition, either the TOC meter 62 or the electrical conductivity meter 63 is provided in the vapor quality control device 60, and the chemical liquid injector 40 is controlled by the controller 62a of the TOC meter 62, or the controller 63a of the electrical conductivity meter 63. The blow-down device 50 may be controlled by

  Further, in the normal operation, the amount of chemical liquid injected from the chemical liquid injector 40 and the amount of blowdown of the boiler water W2 by the blowdown device 50 may be proportional to the flow rate of the boiler feed water W1 supplied to the boiler 20. . In this case, the cause of increasing the electrical conductivity value of the condensed water W3 of the supply steam S2 may be an increase in inorganic impurities in the boiler feed water W1 for some reason.

  Further, an alarm device is provided in the TOC meter 62 or the electric conductivity meter 63 in place of the controllers 62a and 63a, and when the TOC value or the electric conductivity value exceeds a set value, an alarm is issued from the alarm device. 40 or blow-down device 50 may be operated manually.

Embodiment 2. FIG.
FIG. 3 shows an arrangement of main equipment around a boiler apparatus according to another embodiment of the present invention.
The difference between the boiler device A of the second embodiment and the boiler device A of the first embodiment is that the feed water heating device 70 for heating the boiler feed water W1 is provided in the feed water tank 10, and the TOC is set in the steam quality control device 60. Instead of the meter 62 and the conductivity meter 63, a dissolved oxygen meter 64 is provided, and the feed water heating device 70 is controlled by the amount of dissolved oxygen in the supply steam S2 measured by the dissolved oxygen meter 64. .

  The feed water heating device 70 includes a steam heater 71 provided in the feed water tank 10, and a control valve 72 that controls the amount of steam to the steam heater 71 on and off, and the feed water tank is controlled by the control valve 72. The temperature of the boiler feed water W1 in 10 is controlled. In addition, the thing in the boiler apparatus A (For example, what was discharged | emitted from the blowdown drum 52) is used for the steam for heating used.

  That is, the dissolved oxygen meter 64 is electrically connected to the feed water heating device 70 by wiring so that the control valve 72 can be automatically controlled, and the dissolved oxygen meter 64 is connected to the feed water heating device 70. In connection with this, the controller 64a which performs the change driving | operation of the boiler apparatus A is provided. When the measured dissolved oxygen amount in the supply steam S2 exceeds a predetermined set value (preferably 1 mg / L, more preferably 0.5 mg / L), the controller 64a sets the dissolved oxygen amount to the set value. Until the temperature decreases, the control valve 72 is opened, and the temperature of the boiler feed water W1 in the feed water tank 10 is raised or changed so as to maintain a constant value after the rise. Since the dissolved oxygen amount in the supply steam S2 is considered to be proportional to the dissolved oxygen amount in the boiler feed water W1, it can be reduced by increasing the temperature of the boiler feed water W1 in the feed water tank 10.

  Next, an operation method of the boiler apparatus A will be described. In addition, since the method of normal operation is the same as the operation method of the boiler apparatus A of Embodiment 1, description is abbreviate | omitted.

  When the amount of dissolved oxygen in the boiler feed water W1 increases for some reason, the amount of dissolved oxygen in the supply steam S2 also increases accordingly. In this case, since the dissolved oxygen meter 64 measures the amount of dissolved oxygen exceeding the set value, the controller 64a opens the control valve 72, sends steam to the steam heater 71, and sets the temperature of the boiler feed water W1 in the feed water tank 10. Raise etc. Then, the controller 64a continues this change operation until the dissolved oxygen amount in the supply steam S2 decreases from the set value. When the dissolved oxygen amount in the supply steam S2 decreases from the set value, the controller 64a performs the change operation. The operation of the boiler apparatus A is returned to the previous normal operation.

  As described above, in the operation method of the boiler apparatus A, the amount of dissolved oxygen in the supply steam S2 is not increased from the set value, so the supply steam S2 is used due to the dissolved oxygen. Corrosion occurring in the steam using facility 110 and the pipes L10 to L15 can be reliably prevented. In this operation method of the boiler apparatus A, when the amount of dissolved oxygen in the supply steam S2 decreases from the set value, the operation of the boiler apparatus A is returned to the normal operation before the change, so The amount of dissolved oxygen is not reduced excessively (more than necessary).

  Further, in the operation method of the boiler apparatus A, when the condensate of the supply steam S2 is used as the boiler feed water W1, the amount of dissolved oxygen in the boiler feed water W1 can be reduced, and deterioration of water quality due to corrosion can be suppressed. This condensate can be effectively used as boiler feed water W1.

  An alarm device is provided in the dissolved oxygen meter 64 in place of the controller 64a. When the dissolved oxygen amount in the supply steam S2 exceeds a set value, an alarm is issued from the alarm device, and the steam amount to the steam heater is set by the operator. May be operated by a manual valve.

  Moreover, you may perform removal of dissolved oxygen using chemical treatment, for example, the chemical | medical solution injection | pouring apparatus 40 which uses a deoxidizer. In this case, when the amount of dissolved oxygen in the supply steam S2 exceeds the set value, the controller 64a increases the stroke of the chemical injection pump 42 and injects a large amount of the chemical solution containing the oxygen absorber into the boiler feed water W1. When the amount of dissolved oxygen decreases from the set value, the stroke of the medicinal pump 42 is returned to the normal operation state.

  Further, the removal of dissolved oxygen may be performed by a mechanical treatment, for example, a nitrogen deaerator using nitrogen gas. In this case, when the dissolved oxygen amount of the supply steam S2 exceeds the set value, the controller 64a guides the boiler feed water W1 to the nitrogen deaerator so as to reduce the dissolved oxygen amount in the boiler feed water W1, and the dissolved oxygen amount is reduced. If it reduces from a setting value, a nitrogen deaerator will be bypassed and the boiler feed water W1 will be supplied to the boiler 20, and the operation | movement of the boiler apparatus A will be returned to a normal operation.

Embodiment 3. FIG.
FIG. 4 shows an arrangement of main equipment around a boiler apparatus according to another embodiment of the present invention.
The difference between the boiler device A of the third embodiment and the boiler device A of the first embodiment is that a pH meter 65 is provided in the steam quality control device 60 in place of the TOC meter 62 and the electrical conductivity meter 63, and the pH meter The flow rate adjusting valve 51 of the blow-down device 50 is controlled by the pH value in the supply steam S2 measured by 65.

  That is, the pH meter 65 is electrically connected to the blow-down device 50 by wiring so that the flow rate adjusting valve 51 can be automatically controlled, and the pH meter 65 has a relationship with the blow-down device 50. Thus, a controller 65a for causing the boiler device A to perform a change operation is provided. When the measured pH value in the supply steam S2 deviates from the predetermined setting range 5 to 7, the controller 65a increases the opening of the flow rate adjustment valve 51 by a predetermined amount until the pH value falls within the setting range. The operation (change operation) that increases the blow-down amount of the boiler water W2 is performed. Normally, the pH value in the supply steam S2 is not so much smaller than 5, and here, the case where the pH value exceeds 7 is described.

  Next, an operation method of the boiler apparatus A will be described. In addition, since the method of normal operation is the same as the operation method of the boiler apparatus A of Embodiment 1, description is abbreviate | omitted.

  For example, when the impurity concentration in the boiler water W2 increases, carry-over easily occurs in the boiler 20, and the boiler water W2 having a high pH value is mixed into the steam S1, and the pH value of the supply steam S2 increases. In this case, in order for the pH meter 65 to measure a pH value that deviates from the set range, the controller 65a sends a signal to the blow-down device 50 to open the opening of the flow rate adjustment valve 51 larger than the current state, and from the boiler 20 Increase blowdown amount. Then, the controller 65a continues this change operation until the pH value of the supply steam S2 falls within the set range. When the pH value of the supply steam S2 falls within the set range, the controller 65a ends the change operation, The operation of the boiler device A is returned to the previous normal operation.

  As described above, in the operation method of the boiler apparatus A, the pH value of the supply steam S2 is set within the set range. Therefore, the steam using facility 110 in which the supply steam S2 is used due to the pH value. Corrosion occurring in the pipes L10 to L15 can be reliably prevented.

  Further, in the operation method of the boiler apparatus A, when the condensate of the supply steam S2 is used as the boiler feed water W1, the pH value of the boiler feed water W1 can be maintained within an appropriate range, and deterioration of water quality due to corrosion is suppressed. Therefore, this condensate can be effectively used as boiler feed water W1.

  The boiler feed water W1 is obtained by mixing the condensate having a relatively high pH value and the raw water W0 having a relatively low pH value in the feed water tank 10, so that the change operation is performed by the amount of blowdown from the boiler 20. It is good also as an operation which increases the ratio of the raw | natural water W0 with respect to boiler feed water W1, without making it increase. Of course, the change operation may be a combination of an increase in the blowdown amount and an increase in the ratio of the raw water W0 to the boiler feed water W1.

  Further, an alarm device is provided in the pH meter 65 in place of the controller 64a so that an alarm is issued from the alarm device when the pH value of the supply steam S2 deviates from the set range, and the blow-down device 50 is operated manually. May be.

  Further, in the boiler apparatus A of the first to third embodiments, the measurement by the TOC meter 62, the electrical conductivity meter 63, the dissolved oxygen meter 64, and the pH meter 65 is performed not only at a constant time but for a predetermined time every fixed time. Based on the measured values, the controllers 62a, 63a, 64a, 65a may control the chemical liquid injector 40, the blowdown device 50, the feed water heater 70, and the like.

  In the boiler apparatus A of the first to third embodiments, the stroke adjustment of the chemical injection pump 42 by the controllers 62a and 65a and the opening adjustment of the flow rate adjustment valve 51 and the control valve 72 by the controllers 63a and 64a are performed at a time. May be performed, or may be changed little by little to a predetermined value, or may be additionally performed when the measurement value does not change after being performed once.

  In addition, the measured TOC value, electrical conductivity value, and dissolved oxygen value are provided with an allowable value and a change operation start setting value smaller than this, so that these measured values do not exceed the allowable value reliably. Good. Further, a normal operation return set value smaller than the changed operation start set value may be provided to prevent the changed operation and the normal operation from being repeated frequently. In the case of the pH value, a normal operation return setting value may be provided between the upper and lower changed operation start setting values.

  In addition to those shown in the first to third embodiments, a combination of TOC, electric conductivity, dissolved oxygen concentration, and pH is considered, and the combined one is measured simultaneously to operate the boiler apparatus A. May be.

  Furthermore, the changed operation may be a combination of those shown in the first to third embodiments, or may be another operation.

  The present invention can be applied to various boilers such as various factory boilers and power plant boilers.

It is a figure which shows the main equipment arrangement | positioning around the boiler apparatus which concerns on Embodiment 1 of this invention, and flows of water, a vapor | steam, a signal, etc. It is a flowchart which shows the operating method of the boiler apparatus shown by FIG. It is a figure which shows the main equipment arrangement | positioning around the boiler apparatus which concerns on Embodiment 1 of this invention, and flows of water, a vapor | steam, a signal, etc. It is a figure which shows the main equipment arrangement | positioning around the boiler apparatus which concerns on Embodiment 1 of this invention, and flows of water, a vapor | steam, a signal, etc.

Explanation of symbols

20 Boiler 40 Chemical Solution Injection Device 50 Blowdown Device 60 Steam Quality Control Device 62 TOC Meter 63 Electrical Conductivity Meter 64 Dissolved Oxygen Meter 65 pH Meter 70 Feed Water Heating Device A Boiler Device H1 Measurement Process H4 Change Operation Process S2 Supply Steam

Claims (7)

A measurement process for measuring the amount of impurities contained in the steam supplied from the boiler device at regular or regular intervals, and the amount of the impurities measured in the measurement process exceeds a preset value for the impurities. A change operation for changing the operating conditions so as to reduce the amount of impurities and operating the boiler device until the amount of the impurities in the supply steam decreases within the set value. A method of operating a boiler device, comprising: a step. 2. The operation method of the boiler apparatus according to claim 1, wherein the impurities are total organic carbon and / or scale-causing substances. A measurement process for measuring the electrical conductivity of condensed water condensed with steam supplied from the boiler device at regular or regular time intervals, and the electrical conductivity value measured in the measurement process is a predetermined set value. If so, the operating conditions are changed to decrease the electrical conductivity value within the set value until the conductivity value of the condensate of the supply steam decreases within the set value. And a change operation step of operating the boiler device. The operation method of the boiler apparatus according to claim 3, wherein the change of the operation condition in the change operation step is to increase a blow-down rate of boiler water. When the amount of dissolved oxygen in the steam supplied from the boiler device is measured constantly or at regular time intervals, and when the amount of dissolved oxygen measured in the measurement step exceeds a preset value A change operation step of changing the operating conditions so as to decrease the dissolved oxygen amount and operating the boiler device until the dissolved oxygen amount in the supply steam decreases within the set value. The operation method of the boiler apparatus characterized by the above-mentioned. The operation method of the boiler apparatus according to claim 5, wherein the change of the operation condition in the change operation step is to increase a temperature of boiler feed water. When the measurement step of measuring the pH of the steam supplied from the boiler device at regular or regular time intervals and the pH value measured in the measurement step deviates from a predetermined setting range, the supply steam A change operation step of operating the boiler device by changing operating conditions so that the pH value falls within the set range until the pH value falls within the set range. Operation method of boiler equipment.

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