JPH0210322B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a scale adhesion state measuring device for continuously and automatically measuring the scale adhesion state in water pipes accompanying the concentration of canned water in a boiler system.
In particular, the scale adhesion state in the water pipe is measured based on the phenomenon that one heating period in intermittent control for heating control increases as the scale adhesion in the water pipe progresses. This relates to a measuring device.

Generally, when a boiler system is operated for a long time, the canned water becomes concentrated, so the concentration of impurities such as calcium, magnesium, and silica contained in the canned water increases, and these impurities precipitate and adhere to the inner surface of the water pipes and grow into scale. It is. Since scale is a poor conductor of heat, it is known that scale adhesion not only reduces the efficiency of heat exchange in the boiler system, but also causes water pipes to reach high temperatures, eventually leading to burnout. There is.

Therefore, in order to deal with this inconvenience, it is necessary to check the state of scale adhesion in the water pipes by regular visual observation, and when scale adhesion has progressed to a certain extent, it is necessary to pass medicine through the water pipes to dissolve and remove the scale. It is being done.

However, in order to visually observe the state of scale adhesion, it is necessary to stop the operation of the boiler system and
The inside of the water pipe had to be observed after blowing out the canned water, which was a time-consuming process.

Therefore, such work is often neglected, and as a result, abnormal scale growth is overlooked, which often leads to burnout of the water pipes, requiring a great deal of time and effort to restore them. It was hot.

In addition, since the work involves stopping the operation of the boiler system, visual observation of scale adhesion is subject to significant restrictions on its frequency, and is far from continuous measurement, making it difficult to accurately grasp the progress of scale adhesion. That was difficult.

Therefore, with conventional boiler systems, it is not possible to automatically and continuously measure the state of scale adhesion in water pipes with high precision, making it difficult to accurately determine when scale should be removed. The problem was that the scale could not grow, allowing abnormal scale growth, and there was an extremely high risk of burning out the water pipes.

The purpose of the present invention is to solve the problem of measuring the state of scale adhesion in water pipes based on the above-mentioned conventional technology, and to solve the problem that one heating period in intermittent control for heating control increases as the concentration of canned water progresses. By calculating the tendency to increase due to the influence of scale adhering to water pipes, it is possible to eliminate the above drawbacks and automatically measure the state of scale adhesion in water pipes with high accuracy and continuously by estimation. The present invention aims to provide an excellent measuring device for scale adhesion in boiler systems.

The configuration of the present invention in accordance with the above object includes a pressure sensor that outputs a steam pressure signal corresponding to the steam pressure in the water pipe, and a pressure sensor that detects that the steam pressure signal has reached an upper and lower limit set value corresponding to the upper and lower limit steam pressure. a first and second comparator to form a vapor pressure detection section;
A heating device for heating the water tube in response to an output signal from each of the first and second comparators, typically a heating control for starting or stopping a burner, is provided to heat the water tube as steam is consumed. When the vapor pressure of When the vapor pressure increases and reaches the upper limit vapor pressure, the second comparator detects this and sends an upper limit vapor pressure signal to the heating control section to stop the heating device.Intermittent control heating control In a boiler system equipped with a heating system, a heating stop period measuring section is attached to measure the heating stop period from when the heating device stops to when the heating device is started; A heating period in which there is no scale adhesion is measured, and a scale adhesion state calculation unit is added to measure the heating period from when the heating is started until the heating stop is stopped, and a heating period in a state where there is no scale adhesion corresponds to the heating stop period measured by the heating stop period measuring unit. That is, by searching for a standard heating period and subtracting the found standard heating period from the heating period measured by the heating period measuring section, it is possible to determine that the efficiency of heat exchange in the water pipes decreases as scale adhesion progresses. Then, by calculating the tendency for the heating period to increase due to the fact that more heat is required to generate a specific steam pressure under a specific steam load,
The present invention is characterized in that the calculation result is output as a scale adhesion state signal.

Now, before explaining the subsequent embodiments of the present invention, the structure and operation of a typical small boiler system to which the structure of the present invention can be attached will be explained as follows.

FIG. 1A is a block explanatory diagram showing the configuration of such a boiler system, and a cross section of the boiler 1 is shown. FIG. 1B is a sectional view taken along the line AA in FIG. 1A.

In the figure, inside a boiler 1, a large number of water pipes 1b are installed along the inner circumferential surface of a wall 1a, and the water pipes 1b are made of a hollow cylindrical body, and the lower end thereof is an annular lower header 1c (water chamber). The upper end portions thereof communicate with the annular upper header 1d (steam chamber), and the lower portions of the lower header 1c and the water pipe 1b,
Canned water is stored.

A combustion chamber 1e is formed in the center of the boiler 1 surrounded by water pipes 1b, and an electric motor 1f is provided above the combustion chamber 1e.
An air passage 1h is provided which communicates with a blower 1g driven by a blower 1g, and a nozzle rod 1i and an electrode rod 1j are vertically provided within the air passage 1h.

The lower end of the combustion chamber 1e communicates with the flue 1k through the hollow portions of a large number of water pipes 1b. From the upper header 1d, a communication pipe 1l extends outside the wall 1a and communicates with the lower header 1c.

A water level gauge 1m and a water level detector 2 for visually displaying the canned water level are installed in the middle of the communication pipe 1l. A water supply control section 3 is connected to the water level detection section 2 , and an output terminal thereof is connected to an electric motor 4 a that drives a water supply pump 4 . An inlet pipe of the water supply pump 4 communicates with a water source (not shown), and a discharge pipe thereof communicates with the lower header 1c.

Further, a pressure detection section 5 is connected to the upper part of the communication pipe 1l, and its output terminal is connected to a combustion control section 6. From the combustion control section 6, control signal lines 6'a~
6'c extends and is connected to each of the electric motor 1f, electrode rod 1j, and fuel pump 6'd. An inlet pipe of the fuel pump 6'd communicates with a fuel tank (not shown),
Its discharge pipe communicates with the nozzle rod 1i. A blow pipe 1n extends from the lower header 1c and communicates with a drainage channel (not shown) via a blower stock 1p, and a steam pipe 1q extends from the upper header 1d and communicates with a desired steam load (not shown).

In the configuration of the boiler system described above, when generating steam, the electric motor 1f drives the blower 1g to forcefully send air into the air passage 1h, and applies a high voltage to the electrode rod 1j to generate steam from the tip of the nozzle rod 1i. The injected fuel is ignited and combusted within the combustion chamber 1e. High-temperature combustion gas generated by such combustion enters the hollow part of the water pipe 1b from the lower end of the combustion chamber 1e, passes through this, reaches the flue 1k, and is exhausted. During this time, heat exchange takes place and the canned water in the water pipe 1b is heated and turned into steam, which is then transferred to the upper header 1d.
The steam is collected and stored at the steam pipe 1q and supplied to the steam load through the steam pipe 1q.

Regarding combustion control, the upper header 1d
The steam pressure in the upper header 1d is extracted through the communication pipe 1l and supplied to the pressure detector 5.
When the combustion control section detects that the vapor pressure within the combustion chamber has reached a preset lower limit vapor pressure, the lower limit vapor pressure signal is sent to the combustion control section. Send to 6.

When the combustion control section 6 receives a lower limit steam pressure signal due to continued consumption of steam and the steam pressure in the upper header 1d falls, the combustion control section 6 starts the electric motor 1f through the control signal line 6'a and starts the blower 1g. Butetsete wind road 1
After purging h with air, a high voltage is applied to the electrode rod 1j through the control signal line 6'b, and at the same time, the fuel pump 6'd is started through the control signal line 6'c to inject fuel from the nozzle rod 1i. is ignited to start combustion.Furthermore, when steam generation continues and the steam pressure rises, and an upper limit steam pressure signal is received from the pressure detector 5, the fuel pump 6'd is activated via the control signal line 6'c. The combustion is stopped by cutting off the fuel supply, and after waiting for the combustion gas to be discharged, the electric motor 1 is stopped through the control signal line 6'a.
Stop f and cut off the air from blower 1g.

Therefore, even if the combustion is controlled intermittently, the upper header 1
The vapor pressure within d can be maintained at a pressure value between the two preset pressure values as the upper and lower limit vapor pressures.

In addition, in a simple device, the start/stop control of the electric motor 1f and the fuel pump 6d, and the application of high voltage to the electrode rod 1j may be performed simultaneously.

Furthermore, regarding the water supply system, changes in the canned water level in the air-water interface in the communication pipe 1l, that is, in the water pipe 1b, are transmitted to the water level detection unit 2, and the water level detection unit 2 detects the canned water level set in advance. When it is detected that the lower limit water level has been reached, a lower limit water level signal is sent to the water supply control unit 3, and similarly, when it is detected that the upper limit water level has been reached, an upper limit water level signal is sent to the water supply control unit 3.

When the canned water level in the water pipe drops due to steam consumption and a lower limit water level signal is received from the water level detection unit 2, the water supply control unit 3 starts the electric motor 4a and causes the water supply pump 4 to lower the water pipe through the lower header 1c. 1
When the water supply to b is started, water supply continues, the can water level rises, and an upper limit water level signal is received from the water level detector 2, the electric motor 4a is stopped to cut off the water supply to the water pipe 1b.

Thus, even with the intermittent water supply control, the water level of the canned water in the water pipe 1b can be maintained at a water level between the upper and lower limit water levels preset.

The intermittent control of water supply and the intermittent control of combustion are performed separately and independently from each other.

Also, when blowing canned water, use blowing stick 1.
By opening p, part or all of the canned water in the lower header 1c and the water pipe 1b can be blown out through the drain pipe 1n.

In addition, blower 1g, air passage 1h, nozzle rod 1i,
The burner consisting of the electrode rod 1j is not limited to this, and if necessary, it is sufficient to heat the canned water in the water pipe 1b to generate steam, so generally an electric heater or the like is also used. Any heating device that includes the above may be used.

Similarly, the combustion control section 6 may also be a heating control section that turns on and off the heating device.

Next, the configuration and operation of an embodiment of the present invention will be described below based on FIGS. 2 to 5.

FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention, and in the figure, components denoted by the same reference numerals as those in FIG. 1 correspond to those in FIG. 1, respectively.

The pressure detection unit 5 includes a pressure sensor 5a to which the steam pressure in the upper header 1d is guided through the communication pipe 1l;
First and second comparators 5 whose respective first input terminals are connected to the output terminal of the pressure sensor 5a.
b, 5c, and first and second comparators 5b, 5
and reference voltage sources 5d and 5e, respectively connected to the second input terminal of c.

The heating control section 6 includes a flip-flop 6b, in which the output terminal of the first comparator 5b is connected to its set terminal, and the output terminal of the second comparator 5c is connected to its reset terminal through an inverter 6a, and a positive-phase flip-flop 6b. It consists of a relay 6e whose output terminal is connected to one end through a driver 6c and the other end is connected to a power source 6d, and the contacts 6e', 6e'', 6e of the relay 6e are connected to the electric motor 1f, the electrode rod 1j, and the fuel pump 6'. It is inserted between each of control signal lines 6'a, 6'b, and 6'c for controlling d and the power supply.

The heating stop period measuring section 7 includes a clock pulse oscillator 7a, an AND gate 7b whose one input terminal is connected to the output terminal of the clock pulse oscillator 7a, and whose other input terminal is connected to the complementary output terminal of the flip-flop 6b. , the output terminal of the AND gate 7b is connected to its input terminal.
c, and a monostable multivibrator 7d whose input terminal is connected to the complementary input terminal of the flip-flop 6b and whose output terminal is connected to the clear terminal of the counter 7c.

The heating period measuring section 8 consists of an AND gate 8b, a counter 8c, and a monostable multivibrator 8d, which are connected in exactly the same way as the heating stop period measuring section 7, and one input terminal of the AND gate 8b is connected to the output of the clock pulse oscillator 7a. terminal, and the other input terminals are respectively connected to the positive phase output terminal of the flip-flop 6b.

The scale adhesion state calculation unit 9 connects to the data bus 9.
a, a microprocessor 9d interconnected by an address bus 9b and a control bus 9c;
memory 9e, first and second input ports 9f, 9g,
an output port 9h, a first and second interrupt input line 9i,
It consists of monostable multivibrators 9k and 9m whose complementary output terminals are connected to each of 9j, and the input terminals of first and second input ports 9f and 9g are connected to the output terminals of counters 7c and 8c, respectively, The input terminals of the monostable multivibrators 9k and 9m are respectively connected to the positive phase output terminal and the complementary phase output terminal of the flip-flop 6b.

Note that 10 is a display section connected to the output port 9h.

FIG. 3 shows the change A in the steam pressure in the upper header 1d extracted to the communication pipe 1l, the upper and lower limit steam pressure signals B output by the first and second comparators 5b and 5c,
C, and the positive phase output signal D of the flip-flop 6b,
FIG. 3 is a waveform chart showing a comparison with E.

In the above configuration, first, the operations of the pressure detection section 5 and the heating control section 6 for controlling heating in a state where there is no scale adhesion will be explained as follows.

The pressure sensor 5a responds to the steam pressure in the upper header 1d guided through the communication pipe 1l and outputs a corresponding steam pressure signal _S1 , as shown in FIG. 3Aa. When the vapor pressure is higher than the lower limit vapor pressure L, the vapor pressure signal S corresponding to the lower limit vapor pressure L supplied from the reference voltage source 5d is lower than the reference voltage V _L equal to the lower limit set value of ₁ . Since the signal _S1 is larger, the first comparator 5b detects this and outputs "1" as shown in FIG. 3Cb.

Then, as the steam pressure decreases as the steam is consumed or the temperature decreases, and as shown in Figure 3 Ac, when the lower limit steam pressure L is reached, the steam pressure signal S ₁ changes to the reference voltage.
Since it becomes smaller than V _L , the first comparator 5b detects this and outputs "0" as shown in FIG. 3 Cd.

Upon receiving the inversion of the output signal of the first comparator 5b from "1" to "0" at the set terminal, the flip-flop 6b is set to "1", and its positive phase output signal is as shown in FIG. 3 De. ``0''
to "1". Upon receiving this signal, the driver 6c becomes conductive, the relay 6e is energized, the contacts 6e', 6e'', and 6e are closed, and the motor 1
Since power is supplied to the electrode rod 1j and the fuel pump 6'd, the canned water is heated.

Thus, while the flip-flop 6b is at "1", heating continues and the vapor pressure continues to rise as shown in FIG. 3Af.

Eventually, as shown in Fig. 3Ag, when the vapor pressure reaches the upper limit vapor pressure H, the vapor pressure signal S ₁
is smaller than the reference voltage _VH , which is equal to the upper limit set value of the vapor pressure signal _S1 corresponding to the upper limit vapor pressure and is supplied from the reference power source 5e, so that the voltage becomes "0" as shown in FIG. 3Bh. The second comparator 5c, which had been outputting "1", now outputs "1", as shown in FIG. 3 Bi.

The inversion of the output signal of the second comparator 5c from "0" to "1" is converted by the inverter 6a into an inversion from "1" to "0" and supplied to the reset terminal of the flip-flop 6b.
Reset this to "0".

Therefore, as shown in FIG. 3Dj, the positive phase output signal of the flip-flop 6b becomes "0", so
Relay 6e becomes de-energized and contacts 6e', 6
e'' and 6e are opened, and heating of the canned water is stopped.

In this way, the period from when the heating device starts until it stops (hereinafter referred to as the heating period) can be specified even during the period when the flip-flop 6b is set to "1", and furthermore, the period from when the heating device stops until it stops is specified. The period until this happens (hereinafter referred to as the heating stop period) is as follows:
This is specified even during the period when the flip-flop 6b is at "0".

In such intermittent control of the heating device, the heating period T ₁ (hereinafter referred to as the reference heating period) when there is no scale adhesion is specified to a value unique to each boiler system depending on the steam load.

After stopping heating, as shown in Figure 3 Ak,
The flip-flop 6b remains at "0" until the steam pressure decreases again as the steam is consumed or the temperature decreases and reaches the lower limit steam pressure L, forming a heating stop period _T2 , after which the same cycle occurs. The operation is repeated to maintain the vapor pressure between the upper limit vapor pressure H and the lower limit vapor pressure L.

Next, the operations of the pressure detection section 5 and the heating control section 6 for heating control in a state where scale adhesion has progressed will be explained as follows.

In a state where scale adhesion has progressed, the scale is a poor conductor of heat, so the thermal conductivity of the water pipe 1b decreases and the efficiency of heat exchange decreases.

Therefore, as long as the amount of heat supplied from the heating device is constant during the heating period, as shown in Fig. 3 Af',
As shown in Fig. 3Ag', the point at which the rising gradient of vapor pressure slows down and reaches the upper limit vapor pressure H is delayed by △ _T1 , and the point at which the flip-flop is reset is also shown in Fig. 3Ej'. As shown, the heating period is increased to T ₁ ′ due to the delay of ΔT ₁ .

In this way, the heating period shows an increasing tendency as scale adhesion progresses, but the heating stop period is dominated by steam consumption, that is, the steam load, and scale adhesion increases. Therefore, after the vapor pressure reaches the upper limit vapor pressure H, as shown in Figure 3 Ak', the slope remains the same as that without scale adhesion until the lower limit vapor pressure L is reached. As a result, as shown in FIG. 3 Em', a heating stop period T ₂ is formed which is the same as the heating stop period when there is no scale adhesion.

Now, although the heating period and the heating stop period are specified even in the state of the flip-flop 6b in this way, the heating period also changes depending on the steam load and tends to increase as the steam load increases. However, it is not possible to directly estimate the state of scale adhesion from the increasing tendency of the heating period.

Therefore, we measure the heating stop period T ₂ that is exclusively controlled by the steam load, search for the reference heating period T ₁ for that steam load based on the measurement result, further measure the heating period, and then The operations of the heating stop period measuring section 7, the heating period measuring section 8, and the scale adhesion state calculating section 9, which work together to calculate the increasing tendency of the period and estimate the scale adhesion state based on this, will be explained below. It is as follows.

Now, when controlling the heating device on and off, the positive phase output signal of the flip-flop 6b becomes "0" during the heating stop period _T2 as shown in _FIG . It becomes "1" during the period. In response to this complementary output signal, AND gate 7b is opened only during the heating stop period, and the clock pulse from clock pulse oscillator 7a is guided to counter 7c for counting.

Then, as shown in FIG. 3Ee', when the flip-flop 6b is inverted from "0" to "1", its complementary output signal is inverted from "1" to "0", and the AND gate 7b is closed. The supply of clock pulses to the counter 7c is cut off, and the counter 7c has the following information:
A digital code representing the heating stop period _T2 is generated and output as a heating stop period signal _S2 .

At the same time, due to the inversion of the complementary output signal of the flip-flop 6b from "1" to "0", the monostable multivibrator 9k is triggered to enter a quasi-stable state, and the first interrupt control line 9i is switched to "0". 0"
and gives a first interrupt command signal to the microprocessor 9d.

The flowchart in FIG. 4 shows the flow of arithmetic processing executed by the microprocessor 9d in response to the first interrupt command signal.

Upon receiving the first interrupt command signal, the microprocessor 9d first executes the process shown in FIG.
The counter 7c outputs a heating stop period signal _S2 representing the heating stop period T2 by sending _a control signal to the counter 7c.
is read from input port 9f and transferred to microprocessor 9d via data bus 9a.

Next, by moving to the process shown in FIG. 4b and adding a specific value to the transferred heating stop period signal _S2 , the reference heating corresponding to the heating stop period represented by this heating stop period signal _S2 is performed. The address of the memory 9e where the period signal _S3 is stored is calculated, the process moves to the step shown in FIG. 4c, and the calculated memory address is temporarily stored in the first register in the microprocessor 9d. After that, the process moves to the step shown in FIG. 4(d) and comes to a stopped state.

Then, for the above arithmetic processing, the counter 7c
After the heating stop period signal _S2 output by the microprocessor 9d is read, the flip-flop 6
The monostable multivibrator 7d, which had been triggered and transitioned to a quasi-stable state, returns to a stable state due to the inversion of the complementary output signal b from "1" to "0", clears the counter 7c, and Prepare for measurement of the next heating stop period. When one heating stop period ends, the positive phase output signal of the flip-flop 6b changes from "0" to "1" as shown in FIG. 3Ee'.
The heating period _T1 begins.

In response to the positive-phase output signal of the flip-flop 6b, the AND gate 8b opens to guide the clock pulse from the clock pulse oscillator 7a to the counter 8c only during the heating period. The counter 8c operates in the same manner as the counter 7c described above, and the third
As shown in Figure Ej', when the positive phase output signal of the flip-flop 6b is inverted from "1" to "0" and the heating period T ₁ ' ends, the heating period signal S ₄ representing the heating period T ₁ ' Output.

At the same time, monostable multivibrator 9
m is triggered and shifts to a quasi-stable state, the second interrupt control line 9j is set to "0", and a second interrupt command signal is given to the microprocessor 9d. The microprocessor 9d that received the second interrupt command signal
This time, execute the process shown in Figure 4e and connect input port 9.
Heating period signal S ₄ representing heating period T ₁ ′ through g
is read and stored in the second register in the microprocessor 9d in the step shown in FIG. 4f, and then the process moves to the step shown in FIG. In arithmetic processing based on a command signal, the address of the memory stored in the first register is transferred to the memory 9e via the address bus 9b to designate the address, and the control signal is transferred to the memory 9e via the control bus 9c.
By operating this signal in read mode, the reference heating period signal _S3 stored at the specified address is read out, and the reference heating period signal S3 is sent to the data bus 9a.
This is taken into the microprocessor 9d through the microprocessor 9d.

Regarding such search processing, a table is formed in the memory 9e according to the relationship between the address(es) and the memory content(s) stored in each address. By specifying an address in the memory 9e and storing a reference heating period signal corresponding to the heating stop period signal in advance at the specified address, the reference heating period corresponding to each of the various heating stop period signals _S2 can be set. The signal _S3 can be searched according to the table.

Figure 5 shows the heating stop period in the table above.
It is a graph showing an example of the relationship between _T2 and the reference heating period _T1 , and such a relationship can be easily determined by actual measurement for each boiler system.

To further explain the above search process based on the graph of _FIG . The value of the heating stop period T ₂ expressed on the horizontal axis is specified, and as shown in Figure b, the reference heating period T expressed on the vertical axis corresponds to the value on the horizontal axis. By searching for a specific value of ₁ , the standard heating period under a specific steam load without scale adhesion can be determined.

When the search process for the standard heating period is completed,
The microprocessor 9d moves to the step shown _{in FIG .}
By subtracting the standard heating period signal S ₃ representing the standard heating period T ₁ retrieved in the step , the increment ΔT ₁ of the heating period T ₁ ′ with respect to the standard heating period T ₁ is calculated, and then in the step i of the same figure. Then, the increment ΔT ₁ is transferred to the display section 10 through the output port 9h as a scale adhesion state signal _S5 .

After that, the microprocessor 9d executes the process shown in FIG.
In the step , the system is stopped and ready for the next calculation process in response to the first interrupt command signal.

Scale adhesion state signal obtained in this way
_S5 tends to increase as scale buildup progresses in the water pipes, and since it represents the increment of the heating period signal _S4 with respect to the reference heating signal _S3 according to the steam load, it is based on this signal. The state of scale adhesion can be estimated regardless of the steam load.

The display unit 10 receives the scale adhesion state signal _S5 from the scale adhesion state calculation unit 9, and displays it directly or by converting it into an index or the like representing scale adhesion in accordance with an empirical formula and visually displaying it. It is.

In the above embodiment, the heating stop period measuring section 7 and the heating period measuring section 8 measure the heating stop period T ₂ and the heating period T ₁ ' for one intermittent control, and
Each outputs one heating stop period signal S ₂ and one heating period signal S ₄ , and based on these, the scale adhesion state calculation unit 9 outputs one scale adhesion state signal S _{5 .}
However, regarding multiple intermittent control,
It is also possible to measure the heating stop period and the heating period, calculate their average value, and process it as one heating stop period signal and one heating period signal.

By doing so, it is possible to avoid variations in the heating stop period signal and the heating period signal caused by instantaneous fluctuations in the boiler system, and there is a practical benefit in that more stable and accurate estimates can be obtained.

Further, in the operation of the above embodiment, the reference heating period signal _S3 is explained as being stored in advance at a predetermined address in the memory 9e, but immediately after cleaning the water pipe, the heating stop period measuring section 7, the heating The table may be automatically created by measuring the heating stop period and heating period corresponding to various steam loads with the period measuring section 8 and writing these into the memory 9e through the microprocessor 9d.

By doing so, there is the practical benefit that a table representing the relationship between the heating stop period unique to each boiler system and the reference heating period can be automatically created in the memory with a simple operation. Furthermore, the first comparator 5b and the second comparator 5c referred to in this specification are not limited to a configuration realized as separate and independent hardware, but the first comparator and the second comparator may be It may also be configured to be realized as a single piece of hardware.

As described above, the present invention provides a boiler system that is provided with a steam pressure detection section and a heating control section to intermittently control a heating device, and is provided with a heating stop period measuring section and a heating period measuring section to determine the heating stop period and the heating period. Measures the period, and also includes a scale adhesion state calculation section,
Based on the heating stop period that represents the steam load, search for a standard heating period in a state where there is no scale adhesion in that steam load, and determine the magnitude of the found standard heating period and the heating period measured by the heating period measuring section. According to the present invention, the present invention is configured to calculate the increasing tendency of the heating period for each steam load as scale adhesion progresses in the water pipes based on the relationship and output this as a scale adhesion state signal. By estimating the state of scale adhesion in water pipes with high precision and automatically performing the process, it is possible to eliminate the previous time-consuming visual observation work and accurately determine when scale should be removed. It has the excellent effect of preventing water pipe burnout caused by abnormal growth of scale.

Furthermore, since calculation processing is performed based on information obtained from relatively short measurements such as the heating stop period and the heating period, the state of scale adhesion can be virtually continuously estimated. Not only can the progress of scale adhesion be accurately grasped, but it also has the effect of securing extremely effective data for analyzing the factors behind scale adhesion.

Moreover, the vapor pressure detection section and the heating control section in the configuration of the present invention are essential components for intermittent control of the heating device, and can be used as they are to generate a start/stop signal for the heating device obtained from the heating control section. Since it is sufficient to add a component for processing, there is an advantage that the configuration is simple, there is no waste, and it can be realized at low cost.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the configuration of a boiler system, Figs. 2 to 5 relate to an embodiment of the present invention, Fig. 2 is a block diagram thereof, Fig. 3 is a waveform diagram of the main part, and Fig. 3 is a waveform diagram of the main part. FIG. 4 is a flowchart showing the procedure of calculation processing in the scale adhesion state calculation section 9 in FIG. 2, and FIG. 5 is a graph showing the relationship between the heating stop period and the reference heating period. 5...Pressure detection section, 5a...Pressure sensor, 5
b, 5c... comparator, 6... heating control section,
7... Heating stop period measuring section, 8... Heating period measuring section, 9... Scale adhesion calculating section, 10... Display section.

Claims (1)

[Claims] 1 a pressure sensor that outputs a steam pressure signal corresponding to the steam pressure of the boiler; a first comparator that detects that the steam pressure signal is a lower limit set value corresponding to the lower limit steam pressure and outputs a lower limit steam pressure signal; , a second comparator that detects that the vapor pressure signal is the upper limit set value corresponding to the upper limit vapor pressure and outputs the upper limit vapor pressure signal; and in response to the lower limit vapor pressure signal, In a boiler system equipped with intermittent control heating control means that starts a heating device for heating the boiler and stops the heating device in response to an upper limit steam pressure signal, A heating stop period measuring means that measures a period and outputs the measurement result as a heating stop period signal, and a heating device that measures a period from when the heating device starts until it stops and outputs the measurement result as a heating period signal. a period measuring means, a scale adhesion state calculating means for executing a calculation for estimating a scale adhesion state in the water pipe based on the heating stop period signal and the heating period signal, and outputting the calculation result as a scale adhesion state signal; The scale adhesion state calculating means calculates the heating stop period signal according to a pre-stored table representing the relationship between the heating stop period in a state where there is no scale adhesion to the water pipe and the corresponding reference heating period. Search for the reference heating period corresponding to the heating stop period specified in the heating period, and perform calculations to calculate the increasing tendency of the heating period with respect to the standard heating period based on the magnitude relationship between the heating period represented by the heating period signal and the standard heating period. A scale adhesion state measuring device in a boiler system, characterized by: