JP2018179475A - Boiler system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a boiler system which can conduct a confirmation test of a safety system.SOLUTION: A boiler system 1 including one or more boiler(s) 20, includes: an automatic blow control part 43 for controlling a full blow for discharging the boiler water in a boiler body 21 to outside when the state of the boiler 20 satisfies a predefined condition; and a safety system confirming part 44 for controlling the boiler 20 to conduct self check including at least a safety circuit check, a flame detection check, and a water level detection check, when the full blow of the boiler 20 is performed by a control of the automatic blow control part 43.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a boiler system capable of performing a safety system confirmation test effectively and reliably without interrupting the operation of the boiler, in a boiler system comprising a plurality of boilers.

Heretofore, in the boiler, in order to secure functional safety, a measure for securing the safety of a machine or the like has been taken by newly adding a control function such as an electronic control, and a safety system is added. For example, in a boiler system consisting of one or more boilers, at least a flame detection function for detecting no flame when there is no flame, and the water level in the boiler is lower than a preset lower limit water level If there is an abnormality in the water level detection function that detects that the water level is lower than the lower limit (also referred to as "low water level") and the flame detection function or water level detection function, the boiler operation is It is necessary to have a safety system that includes a safety circuit that shuts off.
For this reason, in order to confirm whether the safety system actually secures, it is required to actually confirm that the preset requirement level is satisfied.
However, although it is necessary to perform a functional verification test (proof test) in order to confirm whether the function of the safety system is operating correctly, the execution management of the functional verification test (proof test) It was a new burden.
For example, in order to perform a self-check to confirm the flame detection function, the flame can not be seen during combustion by, for example, operating in the absence of a flame or operating a light shielding unit (shutter) built in the flame detection device. It is necessary to confirm that no detection is performed (Patent Document 1, Patent Document 2). For this reason, conventionally, for example, a self-check is performed to set a relatively small time required for steam such as midnight, and temporarily stop combustion and check the flame detection function even when the combustion command is output when the set time is reached. Was doing.
For example, in order to perform the self check which confirms the function of the flame detection apparatus of each boiler in a multi-can-installed boiler system to patent document 1, the operation priority of the boiler which the implementation time of a self check approaches is forcedly performed. It is described that the self-check is performed to lower the lower level and stop the combustion of the boiler whose operation priority is lower and to check the function of the flame detection device related to the boiler.

JP 2012-13246 A Japanese Patent Application Laid-Open No. 10-267273

Patent Document 1 only describes performing individually the function confirmation test of the flame detection device, and does not mention at all the function confirmation test of safety systems other than the flame detection device.
In order to confirm whether the function of the safety system is operating correctly, at least the flame can not be seen during combustion by, for example, operating in the absence of a flame or by operating a light shielding means (shutter) built in the flame detection device. Self-check that the flame detection function to detect flame-free state works effectively (also referred to as “self-diagnosis of flame detection”), lower limit water level when the water level in the boiler is lower than the lower limit water level Self-check (also referred to as “water level detection self-diagnosis”) that the water level detection function that detects lower condition (low water level) works effectively, and when there is an abnormality in flame detection or water level detection, Self-check (also referred to as “self-diagnosis of safety circuit”) that the function of the safety circuit effectively shuts off the operation of the boiler works effectively (also referred to as “safety inspection cycle”) It is necessary to perform in the "also referred to).
For this reason, in a boiler system that controls the number of one or a plurality of boilers, it is required to automatically and effectively perform a confirmation test of the safety system at predetermined intervals without interfering with the boiler operation.

  The present invention provides a boiler system capable of performing a confirmation test of a safety system at predetermined intervals effectively and reliably without interrupting the operation of a boiler, in a boiler system consisting of one or more boilers. The purpose is

  (1) A boiler system comprising one or more boilers, wherein the boiler body automatically or in response to an instruction from the operator when the state of the boiler satisfies a predetermined condition set in advance. An automatic blow control unit configured to perform a full blow for discharging the entire amount of boiler water to the outside, and a case where the full blow of the boiler is performed by the control of the automatic blow control unit, A safety system confirmation unit that controls self-diagnosis including at least a diagnosis related to a safety circuit, a diagnosis related to flame detection, and a diagnosis related to water level detection automatically or in response to an instruction from an operator; The boiler system

  (2) A combustion amount integration unit that integrates an index value related to the combustion amount from the combustion start time after the last full blow of the boiler, and the elapsed time from the combustion start time after the last full blow of the boiler The automatic blow control unit further includes a first integrated value of index values related to the combustion amount of the boiler, which is integrated by the combustion amount integration unit, set in advance in the boiler When the threshold is exceeded, and / or when the elapsed time integrated value of the boiler integrated by the elapsed time integration unit exceeds a second threshold previously set for the boiler, automatically or in response to an instruction from the operator The boiler system according to (1), which performs control so that the entire blowout of the boiler is performed.

  (3) When the entire blowout of the boiler is executed under the control of the automatic blow control unit, the safety system confirmation unit discharges the entire amount of boiler water in the boiler body to the outside and then enters the inside of the boiler body. When water is newly supplied, control is performed so that diagnosis regarding water level detection and diagnosis regarding a safety circuit related to water level detection abnormality are performed, and when the boiler is instructed to start up after all the blows of the boiler have been completed, The boiler system according to (1) or (2), which is controlled to perform diagnosis related to detection and a diagnosis related to a safety circuit related to a flame detection abnormality.

  (4) The automatic blow control unit is further configured to fire the other boiler if the boiler satisfying the predetermined condition is burning and all other boilers are burning. The boiler system according to any one of (1) to (3), wherein the boiler is controlled to lower the combustion amount by increasing the combustion amount of the boiler.

  According to the present invention, in a boiler system comprising one or a plurality of boilers, a boiler system capable of effectively and reliably performing a confirmation test of a safety system at predetermined intervals without interfering with the operation of the boiler Can be provided.

It is a figure showing composition of a boiler system concerning one embodiment of the present invention. It is a figure showing composition of a boiler concerning one embodiment of the present invention. It is a functional block diagram which shows the structure of the local control part with which a boiler is provided. It is a functional block diagram showing composition of a control part with which a number control device is provided. It is a flowchart figure which shows the flow of the process by the number control apparatus (control part) which concerns on one Embodiment of this invention. It is a flowchart figure which shows the flow of the process by the number control apparatus (control part) which concerns on one Embodiment of this invention.

  Hereinafter, a boiler system 1 according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic view of a boiler system 1.

As shown in FIG. 1, the boiler system 1 includes a boiler group 2 including a plurality of (five) boilers 20, a steam header 6 as a steam collecting portion for collecting steam generated in the boiler 20, and steam pressure measurement A steam pressure sensor 7 as a means and a number control device 3 as a number control means are provided.
The boiler group 2 generates steam to be supplied to a steam using facility 18 as a load device.

  The upstream side of the steam header 6 is connected to the boiler group 2 (each boiler 20) via the steam pipe 11. The downstream side of the steam header 6 is connected to a steam using facility 18 via a steam pipe 12. The steam header 6 regulates the mutual pressure difference and pressure fluctuation of the respective boilers 20 by collecting and storing the steam generated in the boiler group 2 and supplies the steam whose pressure is adjusted to the steam use facility 18 It is supposed to be.

  The vapor pressure sensor 7 is electrically connected to the number control device 3 via a signal line 13. The steam pressure sensor 7 measures the steam pressure (pressure of steam generated in the boiler group 2) inside the steam header 6, and the number of signals (vapor pressure signal) related to the measured steam pressure via the signal line 13 Transmit to control device 3.

The boiler system 1 can supply the steam generated by the boiler group 2 to a steam using facility 18 operated by steam through a steam header 6.
The load (required load) required in the boiler system 1 is the steam consumption in the steam using facility 18. At the time of number control, the fluctuation of the steam pressure inside the steam header 6 generated corresponding to the steam consumption is calculated based on the steam pressure (physical quantity) inside the steam header 6 measured by the steam pressure sensor 7 The amount of combustion of each boiler 20 which comprises the boiler group 2 is controlled.

  The required load increases due to the increase in the demand for the steam using facility 18, and the steam pressure inside the steam header 6 will decrease if the amount of steam supplied is insufficient. On the other hand, if the demand load decreases due to the decrease in the demand for the steam using facility 18, and the amount of supplied steam becomes excessive, the steam pressure inside the steam header 6 will increase. For this reason, the fluctuation of the required load can be monitored by the vapor pressure signal from the vapor pressure sensor 7. The boiler system 1 is configured to calculate a target steam amount according to the consumed steam amount (required load) of the steam using facility 18 based on the steam pressure.

  The number control device 3 includes a control unit 4 and a storage unit 5. The number control device 3 can change, for example, setting conditions (such as the priority of the boiler) stored in the storage unit 5 regarding the combustion control of the boiler group 2. The setting conditions may be set or changed in whole or in part manually, or all or in part may be automatically performed.

  The boiler 20 is a step value control boiler or a continuous control boiler that can be burned at a plurality of staged combustion positions. In the step value control boiler, the amount of combustion is controlled by selectively turning on / off the combustion, adjusting the size of the flame, etc., and the amount of combustion can be made stepwise according to the selected combustion position. It is a boiler that can be increased or decreased. More specifically, the step value control boiler is N position control where N (と し て 3) is an arbitrary integer, that is, the amount of combustion of the step value control boiler is stepwise at N positions including the combustion stop state. It is a controllable boiler 20.

  When five boilers 20 are used as step value control boilers, in each boiler 20, the combustion amount and the combustion capacity (combustion amount in the high combustion state) at each combustion position may be set equal. Or, they may be set differently.

  Moreover, the boiler 20 can be replaced with a step value control boiler to make a continuous control boiler. Here, a continuous control boiler is a continuous control boiler which can change a combustion rate continuously and can burn it. For example, it is a boiler in which the amount of combustion can be continuously controlled at least in the range from the minimum combustion state S1 (for example, the combustion state at a combustion amount of 20% of the maximum combustion rate) to the maximum combustion state S2. The continuous control boiler adjusts the amount of combustion by controlling, for example, the opening (combustion ratio) of a valve that supplies fuel to a burner and a valve that supplies combustion air.

The continuous control boiler is controlled by turning on / off the combustion of the continuous control boiler (burner) about the change of the combustion state between the combustion stop state S0 and the minimum combustion state S1 of the continuous control boiler. And in the range from the minimum combustion state S1 to the maximum combustion state S2, the amount of combustion can be controlled continuously.
Note that continuous control of the amount of combustion means that calculations and signals in the local control unit described later are digitally processed and handled in stages (for example, the output of the continuous control boiler (combustion amount) is divided by 1%) Even when it is controlled, it includes the case where the output can be controlled virtually continuously.

Priorities are set to the plurality of boilers 20, respectively. The priority order is used to select the boiler 20 that performs a combustion instruction, a combustion stop instruction, and the like. The priority can be set, for example, using an integer value such that the smaller the numerical value, the higher the priority. In the normal case, the priority is changed at a predetermined time interval (for example, 24 hour interval) under the control of the control unit 4.
The number control device 3 does not forcibly burn each boiler 20 according to the priority, but according to the load fluctuation, according to the priority, burns the high priority boiler 20 and burns the low priority boiler 20 It is equipped with the optimal combustion transition control function that changes the combustion boiler naturally according to the priority by stopping it.

  Each of the plurality of boilers 20 is electrically connected to the number control device 3 via the signal line 16, and the combustion position (combustion state) is controlled by the control of the number control device 3. Further, each of the plurality of boilers 20 can be separated from the control of the number control device 3 by the operation of the driver or automatically.

  In the boiler system 1 configured as described above, the steam generated by the boiler group 2 is supplied to the steam use facility 18 via the steam header 6.

The boiler 20 demonstrated above has the boiler main body 21 in which combustion is performed, and the local control part 22 which controls the combustion position or combustion state of the boiler 20, as shown in FIG.
Further, the boiler 20 is provided with a fuel supply line 23, an air supply line 24, an air / water line 25, a water supply line 26, and a blow line 27 as main lines, and the fuel supply line 23 has a fuel valve 23a. However, the air supply line 24 is provided with a blower 24a, the water supply line 26 is provided with a water supply pump 26a, and the blow line 27 is provided with a blow valve 27a. In addition, the "line" in this specification is a generic term of the line which can distribute | circulate the fluid of a flow path, a path | route, a pipe line, etc.

<Boiler main body 21>
The boiler body 21 includes a plurality of water tubes 211, an upper header 211a, a lower header 211b, a water level detection unit 212, a burner 213, a flame detection device 213a, and a safety circuit (not shown). Further, a combustion chamber (not shown) for heating the water of the water pipe 211 is formed in the boiler body 21.

<Water level detection unit 212>
The water level detection unit 212 includes, for example, three electrode rods 212a having different lengths, and a container-like detection unit main body 212b in which the electrode rods 212a are disposed. The detection unit main body 212b is connected to the upper header 211a via the upper connection pipe, and is connected to the lower header 211b via the lower connection pipe. Thus, the detection unit main body 212 b and the water pipe 211 are in communication with each other, and the water level in the detection unit main body 212 b substantially matches the water level in the water pipe 211.
Further, the three electrode rods 212a are arranged such that their tips (lower ends) are spaced apart from each other in the vertical direction, and are configured to be able to detect the water level in the detection unit main body 212b in stages.
Among these electrode rods, the tip of the longest L rod 212L is disposed at the lower portion in the detection unit main body. The set water level at which the tip of the L bar is located is called the lower limit water level. When the water level in the detection unit main body 212b becomes lower (lower water level) than the lower limit water level during the boiler operation, the operation of the boiler is stopped. The lower limit water level is the pre-purge start water level.
If the water level is lower than the lower limit water level and the low water level is not output, the boiler operation is continued even though the water level is low (so-called "open air condition") Because it is very dangerous, it is necessary to confirm that the low water level is output when the water level is actually lower than the lower limit water level. Hereinafter, the self-check that low water level output is performed when the water level is lower than the lower limit water level is also referred to as L-bar diagnosis.
The tip of the S-bar 212S having the shortest length is disposed at the upper portion in the detection unit main body 212b. The set water level at which the tip of the S rod is located is the start-up initial water level (predetermined water level) and the low combustion water level.
Further, among the electrode rods 212a, the tip of the M-rod 212M which is shorter than the L-rod and longer than the S-rod is disposed between the tip of the L-rod and the tip of the S-rod. The set water level at which the tip of the M rod is located is the high combustion water level.
The water level detection unit 212 may be provided with a water level sensor instead of (or in addition to) the electrode rod 212a. The water level sensor is configured to be able to detect the water level in the detection unit main body 212b steplessly, and is used to control the water level of the boiler water in the water pipe 211.

<Burner 213>
The burner 213 is a combustion device provided in the combustion chamber of the boiler body 21. A fuel supply line 23 connected to a fuel supply source supplies the fuel necessary for combustion. The fuel valve 23 a is an on-off valve that opens and closes the flow path of the fuel supply line 23. The blower 24 a supplies the air used for the combustion of the burner 213 through the air supply line 24.

<Flame Detection Device 213a>
The flame detector 213a is a device for detecting the flame of the burner 213. The flame detection device 213a and the local control unit 22 are connected by a signal line, and the local control unit 22 controls the combustion based on the signal from the flame detection device 213a. More specifically, when the flameless signal is received, the fuel supply is stopped and the combustion of the boiler 20 is stopped to ensure safety.
As described above, if the output with flame is made in the absence of a flame, the fuel will continue to be injected without a flame, which is very dangerous, so the function of the flame detection device 213a In order to perform a self-check to confirm, the flame detection device 213a operates the built-in light shielding means (shutter) to confirm that a flame-free output is performed by making the flame invisible during combustion. It shall have a known mechanism. Hereinafter, self-checking that a flameless output is performed in a state without a flame or a state in which a flame built-in shutter is closed during a flameless state or combustion is also referred to as a flame detection self-diagnosis.

<Safety circuit>
The safety circuit (not shown) is a circuit that shuts off the operation in hardware without intervention of control software in the local control unit 22 when there is an abnormality in the flame detection device 213a or the water level detection unit 212. Thereby, the safety of the boiler system 1 is secured.
For this reason, it is necessary to perform self-diagnosis regarding the safety circuit related to water level detection abnormality when performing self-diagnosis related to water level detection, and self-diagnosis related to the safety circuit related to flame detection abnormality when performing self-diagnosis related to flame detection. Hereinafter, self-diagnosis relating to the safety circuit relating to water level detection abnormality and flame detection abnormality is also referred to as self-diagnosis of the safety circuit.

<Blowline 27>
In general, when the boiler is operated for a long time, the canned water is concentrated and deposits such as sludge accumulate at the bottom of the can, resulting in deterioration of the dryness of steam and damage to related equipment such as valves. For this reason, for example, when the time converted as 100% combustion reaches the predetermined time, and / or the integrated value of the elapsed time from the start of combustion of the boiler reaches a predetermined time. Therefore, it is necessary to stop the operation of the boiler 20 and carry out all the blow processing for discharging the whole amount of canned water in the boiler body to the outside. By doing so, it becomes possible to discharge all the sludge and the like in the boiler body.
For this reason, the lower header 211b is connected to a blow line 27 capable of discharging canned water. The blow line 27 is provided with a blow valve 27a, and is connected to the local control unit 22 by a signal line. The canned water is discharged from the inside of the boiler main body 21 by opening the blow valve 27a in its entirety or a predetermined amount.

<Local control unit 22>
Next, the detailed configuration of the local control unit 22 will be described. FIG. 3 is a block diagram showing a functional configuration of the local control unit 22. As shown in FIG.
The local control unit 22 can control the boiler 20 to change the combustion position or the combustion state according to the required load. The local control unit 22 controls the boiler 20 based on the number control signal by the number control device 3 at the time of number control, and directly controls the boiler 20 at the time of local control.

  As shown in FIG. 3, the local control unit 22 performs a local combustion amount integration unit 221 in order to perform a confirmation test of a safety system (a safety circuit, a flame detection function, and a water level detection function) related to functional safety of the boiler 20. The local elapsed time integration unit 222, the local automatic blow control unit 223, the flame detection / diagnosis unit 224, the L rod diagnosis unit 225 that performs diagnosis on the L bar for low water level detection, the safety circuit diagnosis unit 226, the local And a safety system confirmation unit 227.

  The local combustion amount integration unit 221 integrates index values related to the amount of combustion from the start of combustion after completion of all the latest blows of the boiler 20. More specifically, the local combustion amount integration unit 221 burns an index value related to the amount of combustion in a combustion start-combustion stop cycle (also referred to as a "combustion cycle") that is executed after completion of the last full blow of the boiler 20. Accumulate at each cycle. By doing so, the local combustion amount integration unit 221 calculates the integrated combustion amount from the combustion start time after completion of the latest all blow of the boiler 20 to the current time. As the index value, for example, a time obtained by converting the combustion time of the boiler 20 as 100% combustion may be adopted. Further, the combustion amount itself of the boiler 20 may be adopted as the index value.

  The local elapsed time integration unit 222 integrates the elapsed time from the combustion start time after completion of all the latest blows of the boiler 20. More specifically, the local elapsed time integration unit 222 is an elapsed time obtained by integrating the combustion time (excluding the combustion stop time) from the combustion start time in the combustion cycle executed after the latest all blow completion of the boiler 20 Accumulate at each combustion cycle. By doing so, the local elapsed time integration unit 222 calculates the integrated combustion time from the start of combustion after completion of the latest all blow of the boiler 20 to the current time.

  The local automatic blow control unit 223 determines that the integrated value of the index value related to the combustion amount of the boiler 20 integrated by the local combustion amount integration unit 221 exceeds the first threshold previously set for the boiler 20 and / or the local progress When the elapsed time integrated value of the boiler 20 integrated by the time integration unit 222 exceeds the second threshold set in advance for the boiler 20, all the blow processing of the boiler 20 is automatically or responded to an instruction from the operator Can be controlled to execute (referred to as "automatic blow").

  The local automatic blow control unit 223 is in a state where the integrated value of the index value related to the combustion amount of the boiler 20 integrated by the local combustion amount integration unit 221 exceeds the first threshold set in advance in the boiler 20 and / or the local progress It is determined whether or not the elapsed time integrated value of the boiler 20 integrated by the time integration unit 222 exceeds a second threshold set in advance for the boiler 20 (also referred to as a "blow notification alarm"). When the notification alarm is determined, the number control device 3 may be notified. Also, for example, a lamp (not shown) may be turned on or a message may be displayed on a display unit (not shown). By doing so, it is possible to notify the operator that it has reached a time when the boiler 20 needs a full blow. By doing so, the local automatic blow control unit 223 may perform the full blow process in response to an instruction from the operator.

  The flame detection / diagnosis unit 224 self-diagnoses that the flame detection device 213a operates the shutter with a built-in flame detection device so that the flame can not be seen at least during combustion of the boiler 20 to detect no flame. Furthermore, the flame detection and diagnosis unit 224 may self-diagnose that the flame is present when the boiler 20 is in combustion. By doing this, the flame detection and diagnosis unit 224 can self-diagnose the soundness of the flame detection device 213a.

  When the water level detection unit 212 at least the water level of the water pipe 211 in the boiler main body is lower than the lower limit water level (for example, the L rod diagnostic unit 225 is located after the entire blowout of the entire amount of canned water in the boiler main body). Self-diagnosis of detection of low water level (during fixed water supply). By doing this, the L-rod diagnostic unit 225 can self-diagnose the soundness of the water level detection unit 212 (in particular, the L-rod).

  When there is an abnormality in the flame detection device 213a or the water level detection unit 212, the safety circuit diagnosis unit 226 can shut off the operation in hardware without intervention of the control software in the local control unit 22. Self-diagnosis. By doing this, the safety circuit diagnosis unit 226 can self-diagnose the soundness of the safety circuit.

The local safety system confirmation unit 227 controls the local automatic blow control unit 223, or when an instruction from the operator in response to the blow notification alarm of the local automatic blow control unit 223 executes all the boilers 20, the boiler main body When the entire amount of boiler water (canned water) inside is discharged to the outside, when water is newly supplied into the boiler main body, the water level is automatically output to the L-bar diagnostic unit 225 automatically or in response to an instruction from the operator. It can be controlled to perform a self-diagnosis on detection. At that time, the local safety system confirmation unit 227 can control the safety circuit diagnosis unit 226 to perform self-diagnosis regarding the safety circuit related to the water level detection abnormality automatically or in response to an instruction from the operator .
The local safety system checking unit 227 controls the flame detection / diagnosis unit 224 to perform self-diagnosis regarding flame detection when the boiler is instructed to start up after all the blows of the boiler are completed. Control can be performed to perform a self-diagnosis on the safety circuit related to a flame detection abnormality.
By doing this, the local safety system confirmation unit 227 controls the boiler 20 to execute flame detection self-diagnosis, L-bar diagnosis, and self-diagnosis of the safety circuit at the timing of all the blows of the boiler. It becomes possible.

  In the boiler system 1 in which the combustion control of the boiler group 2 is performed based on the number control signal by the number control device 3, the local automatic blow control unit 223 and the local safety system check unit 227 It is controlled based on the control signal.

Next, details of the number control device 3 will be described.
The number control device 3 calculates the necessary combustion amount of the boiler group 2 corresponding to the required load and the combustion state of each boiler 20 corresponding to the required combustion amount based on the steam pressure signal from the steam pressure sensor 7 A number control signal is transmitted to the boiler 20 (local control unit 22). As shown in FIG. 1, the number control device 3 includes a control unit 4 and a storage unit 5.

The control unit 4 controls the combustion state and priority of each boiler 20 by giving various instructions to each boiler 20 via the signal line 16 and receiving various data from each boiler 20. Each of the boilers 20 controls the boilers 20 according to the instruction when it receives a signal indicating a change instruction of the combustion state from the control unit 4.
Furthermore, in the boiler system including the plurality of boilers 20, the control unit 4 controls each of the boilers 20 so that the safety system confirmation test can be performed effectively and reliably without interrupting the operation of the boilers.
The detailed configuration of the control unit 4 will be described later.

The storage unit 5 is from the content of the instruction given to each boiler 20 under the control of the control unit 4, the combustion state received from each boiler 20, and the current time from the start of combustion after completion of all the latest blows of each boiler 20. Information such as the integrated time of the integrated value of the index value for the amount of combustion to reach the combustion time from the start of combustion after the completion of the last blow of each boiler 20 to the current time (excluding the combustion stop time) The information of the setting of the priority of the boiler 20 (the priority of each boiler 20 and its setting / change time etc.), the information of the setting regarding the change (rotation) of the priority, etc. are stored. As described above, the priority is changed at predetermined time intervals (for example, 24 hour intervals) under the control of the control unit 4.
The storage unit 5 also stores the sum of the output steam amount output from each boiler 20 and the output steam amount output from each boiler 20.

Next, the detailed configuration of the control unit 4 will be described. FIG. 4 is a block diagram showing a functional configuration of the control unit 4.
In the boiler system 1 including one or more boilers 20, at least the flame detection self-diagnosis, L-bar diagnosis, and safety circuit of each boiler 20 effectively and reliably without interrupting the operation of the boiler group 2 In order to conduct a confirmation test of the safety system including self-diagnosis, as shown in FIG. 4, the control unit 4 has a combustion amount integration unit 41, an elapsed time integration unit 42, an automatic blow control unit 43, and a safety system. And a confirmation unit 44.

<Combustion Amount Accumulator 41>
The combustion amount integrating unit 41 acquires, from each local control unit 22, an integrated amount obtained by integrating index values related to the combustion amount from the combustion start time after completion of the last blow of each boiler 20 to the current time, and integrates the index values. The amount is associated with each boiler 20 and recorded in the storage unit 5.

<Elapsed time integration unit 42>
The elapsed time integration unit 42 acquires, from each local control unit 22, an elapsed time integration amount obtained by integrating the combustion time from the start of combustion after completion of the last blow of each boiler 20 to the present time (excluding the combustion stop time). Then, the elapsed time integrated amount is associated with each boiler 20 and recorded in the storage unit 5.

<Automatic blow control unit 43>
When the state of the boiler 20 included in the boiler group 2 satisfies a preset predetermined condition, the automatic blow control unit 43 completely blows the boiler water (canned water) in the boiler main body 21 to the outside. It instructs the local control unit 22 (local automatic blow control unit 223) of the boiler to execute.
Here, the predetermined condition is, for example, the integrated value of the index value regarding the amount of combustion integrated from the start of combustion after completion of the last full blow of the boiler 20 to the current time by the combustion amount integrating unit 41 of the boiler 20 In the case where it exceeds the first threshold set in advance to the boiler 20 or exceeds the first threshold (also referred to as “condition 1”), and / or the combustion after the last all blows of the boiler 20 is completed by the elapsed time integration unit 42 The elapsed time integrated value integrated from the start time to the current time may be equal to or greater than a second threshold set in advance in the boiler 20 or may exceed the second threshold (also referred to as “condition 2”). The first threshold and the second threshold can be set for each boiler 20.

The automatic blow control unit 43 is a case where the boiler 20 satisfying the predetermined condition (for example, the condition 1 and / or the condition 2) is burning, and all the boilers other than the boiler 20 burn. Control to lower the combustion amount (or the combustion rate) of the boiler 20 satisfying the predetermined condition (for example, the condition 1 and / or the condition 2) by raising the combustion amount (or the combustion rate) of another boiler You may do it.
By doing so, even if all the boilers 20 are burning, under the control of the number control, the boilers 20 satisfying the predetermined condition (for example, the condition 1 and / or the condition 2), for example, optimum combustion The transition control function can enable restart by stopping and starting.

<Safety system confirmation unit 44>
The safety system confirmation unit 44 relates to at least a diagnosis related to the safety circuit and a flame detection with respect to the boiler 20 when the entire blowout of the boiler 20 satisfying the predetermined condition is executed by the control of the automatic blow control unit 43. The local control unit 22 (local safety system confirmation unit 227) of the boiler 20 is instructed to perform a self-diagnosis including a diagnosis and a diagnosis regarding water level detection.
More specifically, in response to an instruction from the control unit 4 (safety system confirmation unit 44), the local control unit 22 (local safety system confirmation unit 227) determines the total amount of boiler water (can water) in the boiler main body. Controls the L-bar diagnostic unit 225 to perform a self-diagnosis related to water level detection when water is newly supplied into the boiler main body after the water is discharged to the outside, and the safety circuit diagnosis unit 226 is controlled. Control to perform self-diagnosis regarding the safety circuit related to water level detection abnormality.
Further, when the local control unit 22 (local safety system confirmation unit 227) changes the boiler to a high priority and the boiler is instructed to start up by the optimal combustion transition control function of the number control device, the flame detection and diagnosis unit Control is performed to perform self-diagnosis regarding flame detection with respect to 224, and control is performed to perform self-diagnosis regarding a safety circuit related to a flame detection abnormality with respect to the safety circuit diagnosis unit 226.
By doing so, when the boiler 20 satisfies a predetermined condition (for example, the condition 1 and / or the condition 2), it relates to a safety circuit related to L bar diagnosis and water level detection abnormality from full blow processing of the boiler 20 to combustion start. A verification test (self-check) of the safety system including self-diagnosis, flame diagnosis, and self-diagnosis relating to the safety circuit related to abnormal flame detection is automatically performed at predetermined intervals.
Further, the safety system confirmation unit 44 records, in the storage unit 5, history information including the date when the confirmation test (self-check) of the safety system was performed.

[Process flow of control unit 4]
Next, a series of flows of control by the number control device 3 (the control unit 4) and the local control unit 22 in the present embodiment will be described with reference to FIGS. 5 and 6. FIG.5 and FIG.6 is a flowchart figure which shows the processing content by the boiler 20 (local control part 22), and the processing content of the number control apparatus 3 (control part 4).

  First, referring to the left side of FIG. 5 and FIG. 6, the local control unit 22 relates to automatic blowout of the boiler 20, diagnosis regarding the safety circuit, and flame detection based on an instruction from the number control device 3 (control unit 4). A process of performing self-diagnosis including diagnosis and diagnosis regarding water level detection will be described.

  In step S100, the local control unit 22 (local combustion amount integration unit 221) integrates index values regarding the amount of combustion from the start of combustion after the completion of the last full blow of the boiler 20 to the current time, Notify the control unit 4).

  In step S101, the local control unit 22 (local elapsed time integration unit 222) integrates the combustion time (excluding the combustion stop time) from the combustion start time after completion of the latest all blow of the boiler 20 to the present time, It notifies the control device 3 (control unit 4).

In step S102, the local control unit 22 (local automatic blow control unit 223) determines whether or not the boiler 20 satisfies a predetermined condition. For example, whether the integrated value of the index value related to the combustion amount of the boiler 20 integrated by the local combustion amount integration unit 221 exceeds the first threshold previously set in the boiler 20 (condition 1) and / or the local elapsed time It is determined whether the elapsed time integrated value of the boiler 20 integrated by the integrating unit 222 exceeds a second threshold value set in advance for the boiler 20 (condition 2).
If the integrated value of the index values related to the amount of combustion exceeds the first threshold and / or the elapsed time integrated value exceeds the second threshold (Yes), the process proceeds to step S103. If the integrated value of the index value related to the combustion amount and the elapsed time integrated value do not exceed the first threshold and the second threshold, respectively (No), the process proceeds to step S100.

  In step S103, the local control unit 22 notifies the number control device 3 (control unit 4) of a blow notification alarm.

  In step S110, the local control unit 22 (local automatic blow control unit 223) responds to a blow process instruction of the relevant boiler from the number control device 3 (control unit 4) or an instruction from the operator in response to the blow alarm. Then, the entire blow of the boiler 20 is performed.

In step S111, the local control unit 22 (local safety system confirmation unit 227) discharges the entire amount of boiler water (canned water) in the boiler main body to the outside, and then, when water is newly supplied into the boiler main body, Self-diagnosis for water level detection (L-bar diagnosis) for L-bar diagnosis unit 225 automatically or in response to an instruction from the operator (self-diagnosis for safety circuit related to water level detection abnormality for safety circuit diagnosis unit 226) Control to do.
In step S112, the local control unit 22 (local safety system confirmation unit 227) performs all blow processing, self diagnosis regarding water level detection, and unit control device 3 (control unit that self diagnosis regarding the safety circuit related to water level detection abnormality is completed). Notify 4).

In step S113, the local control unit 22 starts the steaming operation in response to the combustion instruction (the steaming instruction) of the boiler from the number control device 3 (the control unit 4).
More specifically, the combustion stop boiler performs a pre-purge in response to a combustion instruction (caustic instruction) of the boiler concerned from the number control device 3 (control unit 4), and the unburned fuel remaining in the boiler is unburned After the components are removed and pre-purge is complete, the fuel is burned to initiate steam formation.

  In step S114, the local control unit 22 (local safety system confirmation unit 227) controls the flame detection / diagnosis unit 224 to perform a self-diagnosis on flame detection, and performs a self-diagnosis on a safety circuit related to a flame detection abnormality. Control to do.

In step S115, the local control unit 22 (local safety system confirmation unit 227) controls the number of safety systems (diagnosis related to flame detection and diagnosis related to the safety circuit related to the flame detection abnormality) that the confirmation test (self-check) is completed. It notifies the device 3 (control unit 4).
The process in the local control unit 22 has been described above.
Note that after step S104 (before step S110), the local control unit 22 determines the amount of combustion (or combustion) of the boiler 20 that satisfies a predetermined condition based on the combustion instruction from the number control device 3 (control unit 4). Control steps may be inserted to lower the rate or stop combustion.

  Next, referring to the right side of FIG. 5 and FIG. 6, the number control device 3 (control unit 4) performs automatic blow processing on each boiler 20, diagnosis on safety circuit, diagnosis on flame detection, diagnosis on water level, and water level An operation of instructing a self-diagnosis process including a diagnosis regarding detection will be described. Number control device 3 (control unit 4) is an integrated amount obtained by integrating index values for the amount of combustion from the start of combustion after completion of all blows of each boiler 20 to the current time from each boiler 20, and each boiler It is assumed that an elapsed time integrated amount obtained by integrating the combustion time (excluding the combustion stop time) from the combustion start time after completion of all 20 latest blows to the present time is acquired at a predetermined timing.

  In step S200, the number control device 3 (control unit 4) receives a blow notification alarm from the boiler 20 (local control unit 22).

  In step S210, the unit control device 3 (control unit 4) instructs all the blow instructions and the safety system to the boiler 20 that has notified the blow notification alarm (diagnosis related to water level detection, and diagnosis related to safety circuit related to water level detection abnormality) Make a confirmation test (self-check) instruction.

  In step S220, the number control device 3 (control unit 4) confirms that the water level of the water pipe 211 has risen to the predetermined water level by the completion of the entire blowing operation of the boiler 20 and the feed water control. Instructs the verification test (self-check) of the instruction and safety system (diagnosis related to flame detection and diagnosis related to the safety circuit related to flame detection abnormality).

  In step S230, the number control device 3 (control unit 4) records the end of the confirmation test of the safety system.

The following step S205 may be inserted after step S200 (before step S210).
In step S205, the number-of-units control device 3 (control unit 4) determines that the boiler 20 satisfying the predetermined condition is burning, and all other boilers other than the boiler 20 are burning. The amount of combustion (or the rate of combustion) of the boiler is increased, and an instruction to reduce the amount of combustion (or the rate of combustion) of the boiler 20 or stop the combustion is issued.
By the above, the number control device 3 performs the all-blow process and the subsequent restart process on the boiler 20 included in the boiler system 1 when the boiler satisfies the predetermined condition. It is possible to execute flame detection self-diagnosis, L-bar diagnosis, and self-diagnosis of the safety circuit according to the timing of all blows.

As mentioned above, when the boiler system 1 of this embodiment consists of one boiler 20, the state of the boiler 20 is preset by the local control part 22 (local automatic blow control part 223) with which the boiler 20 is provided, for example When the predetermined conditions (for example, condition 1 and / or condition 2) are satisfied, all blows are performed to discharge the entire amount of boiler water in the boiler main body 21 to the outside automatically or in response to an instruction from the operator Control at that time, the local control unit 22 (local safety system confirmation unit 227) performs at least a self-diagnosis including a diagnosis related to the safety circuit, a diagnosis related to flame detection, and a diagnosis related to water level detection Can be controlled.
Further, when the boiler system 1 of the present embodiment is subjected to combustion control based on the number control signal by the number control device 3, predetermined conditions in which the state of the boiler 20 is preset (for example, condition 1 and / or condition 2) The number control device 3 (control unit 4) controls the boiler 20 (local control unit 22) to execute all blows, and the boiler 20 automatically or the operator In response to an instruction from the control unit, control can be performed to perform a self-diagnosis including at least a diagnosis related to the safety circuit, a diagnosis related to flame detection, and a diagnosis related to water level detection.
By doing so, in the boiler system 1 consisting of one or more boilers, the automation test of the entire blow execution of the boiler 20 effectively and reliably checks the safety system without interrupting the operation of the boiler 20 It can be performed.

Further, in the boiler system 1 of the present embodiment, the integrated value of the index value related to the combustion amount of each boiler 20 integrated by the combustion amount integration unit 41 is equal to or greater than the first threshold set in advance for the boiler 20 or the first threshold If it exceeds and / or the elapsed time integrated value of the boiler 20 integrated by the elapsed time integration unit 42 exceeds the second threshold or the second threshold set in advance in the boiler 20 in advance, automatically or from the operator In response to an instruction from the control unit to perform a full blow of the boiler 20, and at least a self-diagnosis including a diagnosis related to a safety circuit, a diagnosis related to flame detection, and a diagnosis related to water level detection Control to do
Thereby, it is possible to automate the execution of the entire blow of the boiler 20 and the confirmation of the safety system.

In the boiler system 1 of the present embodiment, when the entire blowout of the boiler 20 is executed by the control of the automatic blow control unit 43, the entire amount of boiler water in the boiler body 21 is discharged to the outside, When water is newly supplied to the boiler, the diagnosis regarding the water level detection and the diagnosis regarding the safety circuit related to the water level detection abnormality are controlled, and after the entire blowout of the boiler 20 is completed, when the boiler is instructed to start up It is controlled to perform a diagnosis regarding flame detection and a diagnosis regarding a safety circuit relating to a flame detection abnormality.
As a result, the diagnosis related to the safety circuit, the diagnosis related to the flame detection, and the diagnosis related to the water level detection are automatically executed at predetermined intervals after all the blows are performed without forcing the change of priority, etc. be able to.

Further, when the boiler 20 satisfying the predetermined condition is burning and all the other boilers are burning, the automatic blow control unit 43 increases the combustion amount of the other boilers and Control 20 to lower the amount of combustion.
Thereby, even when all the boilers are burning, it is possible to restart the boilers that satisfy the predetermined condition by the optimum combustion transition control function, and secure the safety inspection cycle and confirm the safety system. The execution opportunity of the part 44 can be secured.

  As mentioned above, although one preferable embodiment of the boiler system of this invention was described, this invention is not restrict | limited to the above-mentioned embodiment, It can change suitably.

[Modification 1]
In the present embodiment, the condition 1 and / or the condition 2 is exemplified as the predetermined condition for the number control device 3 (the control unit 4) to instruct the boiler 20 to execute all the blows, but the present invention is limited thereto I will not. As a predetermined condition, in addition to the condition 1 and / or the condition 2 described above, the boiler 20 is in a state where the combustion priority is lowered and the combustion is stopped (also referred to as “condition 3”) And it may be made to include that the boiler 20 concerned is scheduled to be changed by the control part 4 to high priority after predetermined time (for example, one hour after) (it is also called "condition 4").
In this case, the number control device 3 (control unit 4) may execute step S205 'after step S200 and before step S210.
In step S205 ′, the number control device 3 (control unit 4) determines whether the boiler 20 satisfies the condition 3 and the condition 4. If the boiler 20 satisfies the conditions 3 and 4 (Yes), the process proceeds to step S210. When the said boiler 20 does not satisfy the conditions 3 and 4 (No), it returns to step S205 '.
By doing so, each boiler 20 performs setting regarding operation of the boiler system 1 so that predetermined conditions (for example, condition 1 to condition 4) are satisfied every predetermined period (for example, one month). It is possible to automatically execute a confirmation test (self-check) of the safety system of the boiler 20 at regular intervals.

As described above, when the state of the boiler 20 satisfies a predetermined condition (for example, the conditions 1 to 4) set in advance, the number control device 3 (the control unit 4) sends the boiler 20 (local control unit 22) Control the execution of all blows, a self-diagnosis including at least a diagnosis related to the safety circuit, a diagnosis related to flame detection, and a diagnosis It can be controlled to be performed every cycle.
By doing so, in the boiler system 1 consisting of one or more boilers, control is performed such that the entire blow execution of the boiler 20 is performed at every safety inspection cycle without interfering with the operation of the boiler 20. For example, safety inspection cycles can be secured to effectively and reliably perform safety system confirmation tests to meet functional safety level.

[Modification 2]
In the present embodiment, the boiler system 1 including a plurality of (five) boilers 20 is illustrated, but the present invention is not limited to this. The same process can be performed in the boiler system 1 including one or more (arbitrary number) boilers.

[Modification 3]
In the present embodiment, the priority of each boiler 20 is changed at a predetermined time interval (for example, 24 hours interval) set in advance. However, the boiler 20 has predetermined conditions (condition 1 and / or conditions) When 2) is satisfied, the unit number control device (control unit 4) controls to lower the priority of the boiler 20 forcibly, and forcibly raises the priority after performing all the blows. May be
By doing so, it is possible to control the boiler 20 to execute the diagnosis related to the safety circuit, the diagnosis related to the flame detection, and the diagnosis related to the water level detection earlier as soon as the boiler 20 performs the full blow.

[Modification 4]
In the present embodiment, the water level is detected by the electrode rod. However, instead of the electrode rod, for example, a water level sensor capable of detecting the water level in the water pipe 211 in a stepless manner may be provided. In such a case, self-diagnosis of water level detection is performed so as to confirm that the water level sensor outputs low water level when the water level in the water pipe 211 is lower than a preset lower limit water level.

DESCRIPTION OF SYMBOLS 1 boiler system 2 boiler group 3 number control device 4 control part 41 combustion amount integration part 42 elapsed time integration part 43 automatic blow control part 44 safety system confirmation part 5 storage part 20 boiler 21 boiler main body 211 water pipe 211a upper header 211b lower header 212 Water level detection unit 212a Electrode rod 212S S rod 212M M rod 212L L rod 212b Detection unit main body 213 Burner 213a Flame detection device 22 Local control unit 221 Local combustion amount integration unit 222 Local elapsed time integration unit 223 Local automatic blow control unit 224 Flame detection Diagnostic unit 225 L rod diagnostic unit 226 Safety circuit diagnostic unit 227 Local safety system confirmation unit 23 Fuel supply line 23a Fuel valve 24 Air supply line 24a Blower 25 Air and water line 26 Water supply line 26a Water supply pump 27 Low line 27a blow valve

Claims (4)

A boiler system consisting of one or more boilers, wherein
When the state of the boiler satisfies a predetermined condition set in advance, it is possible to execute all blows for discharging the whole amount of boiler water in the boiler body to the outside automatically or in response to an instruction from the operator Automatic blow control unit to control,
When the entire blowout of the boiler is executed by the control of the automatic blow control unit, at least diagnosis on the safety circuit and diagnosis on flame detection for the boiler automatically or in response to an instruction from the operator , A safety system confirmation unit that performs control to perform self diagnosis including diagnosis related to water level detection;
Boiler system equipped with A combustion amount integrating unit that integrates index values related to the amount of combustion from the start of combustion after completion of all the latest blows of the boiler;
An elapsed time integration unit that integrates an elapsed time from a combustion start time after completion of all the latest blows of the boiler;
The automatic blow control unit further includes:
The integrated value of the index value related to the combustion amount of the boiler, which is integrated by the combustion amount integration unit, exceeds a first threshold previously set in the boiler, and / or of the boiler integrated by the elapsed time integration unit. The control according to claim 1, wherein if the elapsed time integrated value exceeds a second threshold value preset for the boiler, control is performed such that all the boilers are fully blown, automatically or in response to an instruction from the operator. Boiler system. The safety system confirmation unit
When the entire blowout of the boiler is executed by the control of the automatic blow control unit, the water level is detected when water is newly supplied into the boiler body after the entire amount of boiler water in the boiler body is discharged to the outside Control the diagnosis and diagnosis regarding the safety circuit related to the water level detection abnormality,
The control according to claim 1 or 2, wherein when the boiler is instructed to start up after completion of the entire blowout of the boiler, a diagnosis relating to flame detection and a diagnosis relating to a safety circuit relating to a flame detection abnormality are performed. Boiler system. The automatic blow control unit further includes:
When the boiler satisfying the predetermined condition is burning, and when all the boilers other than the boiler are burning, the combustion amount of the other boiler is increased to burn the boiler The boiler system according to any one of claims 1 to 3, which is controlled to lower

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