JP3282566B2 - Scale or slime adhesion detection device and detection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and method for detecting scale or slime adherence, and more particularly to an apparatus and method for detecting scale or slime generation in an industrial water system, for example, a paper pulp process white water system or a cooling water system.
About the law .

[0002]

2. Description of the Related Art In various industrial water systems such as a paper pulp process white water system and a cooling water system, scales due to hardness components in water and slime due to microorganisms and organic nutrients in water adhere to the pipes, resulting in blockage of pipes and heat. It causes various adhesion failures such as a decrease in exchange efficiency.

[0003] Therefore, in these water systems, it is necessary to detect the scale or slime adhesion state in the system and take appropriate measures to prevent this adhesion failure. In particular, to prevent these adhesion disorders,
Scale inhibitors and slime removers are used, but in such cases,
It is necessary to grasp the scale and slime adhesion in the system.

Conventionally, there is a monitoring method using a test piece as a method for detecting the state of adhesion of scale and slime. In this method, a test piece is placed in a system, taken out after a certain period of time, and measured for the amount of scale attached and the amount of slime attached.

Further, a differential pressure type scale or slime detecting device is also provided. This device uses a pipe to detect the scale or slime adhesion state by utilizing a phenomenon in which when a scale or slime adheres to a pipe wall, a differential pressure at a pipe entrance increases.

However, in the monitoring method using a test piece, continuous monitoring cannot be performed because the test piece needs to be replaced. Since it is necessary to remove the test piece and measure the amount of scale or slime attached, it cannot be monitored online. There are drawbacks.

In a water system, there are cases where only slime or scale adheres and cases where they adhere simultaneously. However, in a differential pressure type scale or slime detecting device, the tube wall is only affected by a change in differential pressure. There is a disadvantage that it is not possible to distinguish whether the substance attached to the scale is a scale or a slime.

In order to solve the above-mentioned conventional problems, the present applicant has previously filed Japanese Patent Application No. 9-147770 (hereinafter referred to as "the prior application"), and attached to the main body member. Proposed a scale or slime adhesion detection device including a sensor mounting member, a temperature measuring resistor detachable from the sensor mounting member, and an enclosure surrounding the temperature measuring resistor.

A temperature measuring resistor used as a sensor in the scale or slime adhesion detecting device of the prior application has a structure in which the electric resistance increases with an increase in temperature. Or a glass substrate coated with a platinum pattern formed on a ceramic substrate, such as a hot-wire anemometer or a hot-film anemometer.

The resistance thermometer is, for example, a commercially available product having a length of 1c.
It is a small piece having a length of about m, a width and a thickness of several mm. Therefore, according to the present invention, it is possible to reduce the size of the scale or slime adhesion detecting device, and it is possible to directly install the device at any place in the actual process.

When a constant current is applied to the resistance temperature detector, a temperature difference occurs between the liquid and the sensor. In this state, if scale or slime adheres to the resistance temperature detector, the diffusion of heat to the liquid side becomes worse, the heat transfer resistance increases, the temperature of the resistance temperature detector increases, and the electrical resistance increases. By detecting this change in electric resistance as a change in voltage, the state of adhesion of scale or slime can be detected.

In general, on the surface of a high-temperature object, the saturation concentration of the hardness component in water is reduced, so that the hardness component is easily deposited and the scale is easily attached. On the other hand, the propagation of microorganisms is hindered and the slime is hardly attached. . Conversely, on the surface of a low-temperature object, the saturation concentration of the hardness component in water increases, so that the scale is difficult to adhere, but the propagation of microorganisms is not hindered and slime adheres easily.

Therefore, utilizing such a phenomenon, the scale is detected by the first temperature measuring resistor set at a high temperature,
Slime may be detected by a second resistance temperature detector set at a low temperature. Further, in this case, only one of the first and second resistance temperature detectors may be used to detect only the adhesion of the scale or only the adhesion of the slime.

In a steady state, current is not supplied to the resistance temperature detector set at a low temperature, and slime is adhered to the resistance temperature detector while the temperature of the resistance temperature detector is kept at the temperature of the test water (or the current supplied to the resistance temperature detector is reduced. The temperature sensor is set at a relatively low temperature so that slime adheres), and the temperature is increased intermittently (for example, about once a hour for about one minute) to raise the temperature of the temperature sensor. Alternatively, the slime adhesion state may be detected based on the temperature of the resistance temperature detector or the temperature rising rate at this time.

In the scale or slime adhesion detecting device of the prior application, the surrounding area of the resistance temperature detector is surrounded by an enclosure, so that the detection temperature of the resistance temperature detector is not affected by the change in the flow rate of the test water. As a result, it is possible to detect the adhesion of scale and slime with high accuracy.

Further, by providing the enclosure, it is possible to prevent the foreign matter in the test water from colliding with the temperature measuring resistor and damaging the temperature measuring resistor.

[0017]

In the above-described scale or slime adhesion detecting device of the prior application, the main body member is damaged by a certain impact applied to the main body member, and the main body member is broken or cracked. If water invades, the lead wires of the resistance temperature detector etc. may be short-circuited and break down, or the buoyancy of the main body member may be reduced and the main body member may sink into the bottom of the water tank, and the scale or the scale may be affected by sediments on the water bottom. In some cases, slime could not be detected.

The present invention solves the above-mentioned disadvantages of the prior application, and detects a water infiltration in the main body member and immediately takes a countermeasure to thereby prevent a failure or the like of the temperature measuring resistor from occurring. Using an adhesion detection device and such a device
It is an object of the present invention to provide a scale adhesion detection method and a slime adhesion detection method .

[0019]

The scale or slime adhesion detecting device of the present invention has a float sensor attached.
A hollow body member that can be floated on the water surface ,
A sensor mounting member mounted on the main body member, a temperature measuring resistor detachable from the sensor mounting member, a surrounding body surrounding the temperature measuring resistor, and water leakage provided in a hollow portion of the main body member And a sensor. Of the present invention
The slime adhesion detector has a float sensor
A hollow body member that can be floated on the water surface,
A sensor attachment member attached to the main body member, and the sensor
A temperature measuring resistor that can be attached to and detached from the mounting member;
Surrounding enclosure and water provided in a hollow portion of the main body member
A slime adhesion detection device comprising a leak sensor
To switch the value of the constant current that flows through the resistance temperature detector.
And a means for performing the following.

In this scale or slime adhesion detecting device, the infiltration of water into the main body member can be detected by the water leak sensor provided in the main body member, and based on this, the power to the resistance temperature detector is supplied. By stopping or issuing an alarm, a failure or breakage of the resistance temperature detector can be prevented. The scale adhesion detection method of the present invention
Inside the sensor can be mounted and floated on the water surface
An empty body member and a sensor housing attached to the body member;
Attached member and a temperature measuring resistor detachable from the sensor mounting member
And an enclosure surrounding the resistance temperature sensor, and
A scale including a water leak sensor provided in the air space.
Scale adhesion detection device
The amount of current supplied to the resistance temperature detector is
That the temperature of the body should be in the range of 60-100 ° C.
Features. The slime adhesion detection method of the present invention
Sensor can be attached and float on the water surface
Hollow body member and sensor attached to the body member
Attachment member and temperature measuring resistor detachable from the sensor attachment member
And an enclosure surrounding the resistance temperature sensor, and
And a water leak sensor provided in the air space.
The method of detecting slime adhesion with a system adhesion detection device
The amount of current supplied to the resistance temperature detector is
It is recommended that the body temperature be set in the range of 30 to 37 ° C.
Sign.

[0021]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view showing a main part of the scale or slime adhesion detecting device of the present invention, and FIG. 2 is a sectional view taken along the line II-II of FIG. FIG. 3 is a block diagram showing an entire configuration of the scale or slime adhesion detecting device, FIG. 4 is a block diagram showing a configuration of a temperature measuring section of the scale or slime adhesion detecting device, and FIG. It is sectional drawing which shows the example of attachment.

First, the configuration of the main part of this apparatus will be described with reference to FIGS.

The sensor mounting member 21 is provided on the lower surface of the main body member 20.
The temperature measuring resistor 22 as a sensor is detachably attached to a lower end of the sensor attaching member 21 by a union nut 33.

In this embodiment, a platinum pattern is formed on the plate surface of an insulating substrate such as a ceramic as the temperature measuring resistor 22.
This platinum pattern coated with glass is used.

The sensor mounting member 21 and the resistance temperature detector 2
A surrounding body 23 is provided so as to surround 2. In this embodiment, the surrounding body 23 has a cylindrical shape whose lower end is open, and is screwed to a mounting seat 24 on the lower surface of the main body member 20.

The mounting seat 24 is fixed to the main body member 20 by, for example, welding. In this embodiment, the mounting seat 24 has a short cylindrical shape, and is provided with a communication hole 25 communicating the inside and the outside of the cylinder. The communication hole 25 allows the test water to flow into the enclosure, and thereby the test water in the enclosure can be updated.

An electromagnetic float sensor 26 is attached to the lower surface of the main body member 20. The electromagnetic float sensor 26 includes a shaft 27 fixed to the main body member 20, a float 28 movable up and down along the shaft 27, and a cylindrical cover 29 surrounding the float 28. The cover 29 is provided with a large number of communication holes 30 communicating the inside and outside of the cylinder. Reference numeral 31 denotes a cable, which is connected to the resistance temperature detector 22 and the electromagnetic float sensor 26 via lead wires L ₁ , L ₂ , L ₃ , and L ₄ .

The float 28 of the electromagnetic float sensor 26 moves up and down corresponding to the level of the liquid surface of the test water. Then, when the float 28 reaches the lower limit as shown in FIG. 1, the current supply to the temperature measuring resistor 22 is stopped. This allows
Burnout of the resistance temperature detector 22 is prevented.

Further, a water leak sensor (in this embodiment, an electrode type water leak sensor) is provided in the hollow inside of the hollow main body member 20.
40 is provided, and the water leak sensor 40 is connected to the lead wire L
It has been communicated to the cable 31 at _5, L _6.

In this scale or slime adhesion detecting device, since the enclosure 23 is provided so as to surround the resistance temperature detector 22, the resistance resistance element 22 is not affected by the change in the flow rate of the test water, Alternatively, the slime adhesion state can be detected with high accuracy. Further, since the surrounding body 23 is provided, the collision of foreign matter with the temperature measuring resistor 22 is prevented, and the temperature measuring resistor 22
Damage can be prevented. In addition, since the water leak sensor 40 can detect the intrusion of water in the main body member 20, it is possible to prevent the failure of the temperature measuring resistor 22 due to the intrusion of water.

In the present invention, the water leak sensor includes:
A commercially available electrode type water leak sensor, hygrometer, or the like can be used.

In the case of an electrode type water leak sensor, for example, as shown in FIG.
The first and second electrodes 42 and 43 are buried in the sponge 41, and the water enters the main body member 20 so that the sponge 41 contains water. By detecting that a current flows between the electrodes 42 and 43 in the presence, the intrusion of water is detected.

As the hygrometer, any known hygrometer such as a hair hygrometer, a dry and wet bulb hygrometer, a dew point meter, and an electric resistance type hygrometer can be used.

Next, a configuration of a scale or slime detection system using the scale or slime adhesion detection device will be described with reference to FIGS.

As shown in FIG. 3, the scale or slime adhesion detecting system includes a scale adhesion detecting device 2 having a first temperature measuring resistor 1 whose surface temperature is set to a relatively high temperature and a water leak sensor 1A; A slime adhesion detecting device 4 having a second temperature measuring resistor 3 whose surface temperature is set to a relatively low temperature and a water leak sensor 3A, and a temperature measuring resistor 1 and a slime adhesion detecting device 4 of the scale adhesion detecting device 2 Temperature measuring units 2A and 4A that process signals from the temperature measuring resistor 3
And determination units 2B and 4B, a display unit 5 for displaying detection results, and a water leak detection unit 1B that processes signals from the water leak sensors 1A and 3A and transmits the signals to the temperature measurement units 2A and 4A.
3B and display units 1C and 3C for displaying water leakage.

The adhesion amount detection device 2 and 4, using the body member 20 float on the water surface in the water <br/> path.

As the determination units 2B and 4B, the temperature measurement unit 2
A computer or the like that determines the slime adhesion status by calculating the detected temperatures of A and 4A by a predetermined calculation formula can be used.

The display section 5 may be any as long as it can display the determination result, and for example, a monitor television, a liquid crystal panel, a printer, a lamp, a buzzer, or the like can be used.

The water leak detectors 1B and 3B detect, for example, the generation of a current due to the intrusion of water into the main body member 20 and determine that there is a water leak. 4A, a signal to stop power supply is sent to the display unit 1A.
C and 3C are used to send a water leak display signal.
As C and 3C, any device capable of displaying the determination result may be used, and for example, a monitor television, a liquid crystal panel, a printer, a lamp, a buzzer, or the like can be used. The display units 1C and 3C may also be used as the display unit 5 for the scale or slime adhesion state.

As shown in FIG. 4, the temperature measuring units 2A and 4A are provided with an energization control unit 6 for supplying a constant current to the temperature measuring resistors 1 and 3 so that the temperature measuring resistors 1 and 3 reach a predetermined temperature. And a constant current generating unit 7, a voltage measuring unit 8 for measuring a voltage change due to a temperature rise of the resistance temperature detectors 1 and 3, and a temperature calculating unit 9 for calculating a temperature from the measured voltage. Thus, when the water leak sensors 1A and 3A detect a water leak, a signal is sent from the water leak detection units 1B and 3B to the energization control unit 6 of the temperature measurement units 2A and 4A, and the energization is stopped.

[0042] Such scale, using slime adhesion amount detection system, in order to examine the adhesion state of the scale or slime, as shown in FIG. 3, at any point of 10 such waterways actual process water system, the resistance thermometer The adhesion detectors 2 and 4 are used so that the bodies 1 and 3 are immersed in the test liquid (water) .
The main body member is set up floating on the test liquid, and the temperature measurement unit 2A,
4A, the temperature of each of the resistance temperature detectors 1 and 3 is measured, and the scales and slime adhesion states are determined by the determination units 2B and 4B from the measured temperatures, and the results are displayed on the display unit 5.

Specifically, the operation is performed in the following procedure.

[In the case of scale detection] [1] In the initial state (the state where there is no deposit on the surface of the first resistance temperature detector 1), the surface temperature of the first resistance temperature detector 1 The current value of the constant current generator 7 is set so that the temperature of the constant current generating unit 7 is set to a temperature at which the microorganisms that can easily cause slime do not easily propagate, for example, 60 to 100 ° C. [2] The voltage between both ends of the RTD 1 is measured by the voltage measuring unit 8. [3] From the voltage measured by the voltage measuring section 8, the temperature calculating section 9
Calculates the temperature of the first resistance temperature detector 1 and sends the temperature data to the scale adhesion determination unit 2B. [4] The scale adhesion determination unit 2B determines that “scale adhesion is present” when the measured temperature rises above a predetermined threshold value compared to the initial state. Further, the amount of adhesion is determined from the temperature and the rate of increase. [5] Upon receiving the determination result of the scale adhesion determination unit 2B, the display unit 5 displays the determination result.

[In the case of slime detection (first method)] [1] In the initial state (the state where there is no deposit on the surface of the second resistance bulb 3), the surface of the second resistance bulb 3 The current value of the constant current generator 7 is set so that the temperature is a temperature at which the scale does not easily adhere and does not hinder the growth of microorganisms that are a source of slime, for example, 30 to 37 ° C. [2] The voltage across the second resistance bulb 3 is measured by the voltage measurement unit 8
Measure with [3] From the voltage measured by the voltage measuring section 8, the temperature calculating section 9
Calculates the temperature of the second resistance thermometer 3, and sends the temperature data to the slime adhesion determination unit 4B. [4] The slime adhesion determination unit 4B determines that “slime is present” when the measured temperature rises above a predetermined threshold value compared to the initial state. Further, the amount of adhesion is determined from the temperature and the rate of increase. [5] Upon receiving the determination result of the slime adhesion determination unit 4B, the display unit 5 displays the determination result.

[Slime Detection (Second Method)] Slime detection can also be performed by the following methods (1) to (7). In this case, the temperature measuring unit 4A is provided with a unit capable of switching a value of a constant current supplied to the resistance bulb 3 (not shown).

(1) Resistance thermometer 3 having no deposit on its surface
Is immersed in the test solution, and no electricity is supplied for one hour. (2) After a lapse of one hour, a constant current of a predetermined value or more is applied to the resistance bulb 3 for one minute. The constant current equal to or higher than the predetermined value is a current value (constant value) at which the temperature of the resistance bulb 3 becomes preferably 40 to 100 ° C, more preferably 45 to 80 ° C, and particularly preferably 55 to 65 ° C. (3) Immediately at the same time as the start of energization, the applied voltage rapidly rises to reach an equilibrium temperature. The applied voltage when the temperature reaches the equilibrium temperature, or a predetermined time (for example, 1
The applied voltage after the elapse of (minutes) is measured by the voltage measuring unit 8. (4) Based on the voltage measured by the voltage measuring section 8, the temperature calculating section 9 calculates the temperature of the temperature measuring resistor 3, and sends the temperature data to the slime adhesion determining section 4B. (5) The slime adhesion determination unit 4B determines the presence or absence of slime adhesion and the amount of slime adhesion based on the temperature data. (6) The display unit 5 displays the determination result of the slime adhesion determination unit 4B.
To display. (7) After the elapse of one hour, the determination of slime adhesion is performed again according to the procedures (1) to (6). In addition, the above (3)-
In (5), the voltage after a predetermined time has elapsed after the start of energization is measured, and the slime adhesion state is determined based on the measured voltage. The voltage rise rate (mV / msec) for a very short time after the start of energization May be determined, and the slime adhesion state may be determined based on the determination result.

In the above procedures (1) to (7), a constant current of a predetermined value or more is applied to the RTD 3 once an hour for a short time (for example, 1 minute). During this time (for example, during one hour), no current is supplied to the resistance temperature detector 3 at all. However, in the present invention, a minute constant current may be supplied to the resistance bulb 1 during this one hour. This minute constant current is a temperature at which the surface temperature of the resistance temperature detector 3 is higher than the temperature of the water and does not hinder the generation of slime, for example, 30 to 37.
Set to ° C.

It goes without saying that the scale and slime detection can be performed simultaneously. The threshold value used as a criterion in the determination units 2B and 4B is determined according to the detection target, such as the concentration of the water-based hardness component, the concentration ratio, the turbidity, the BOD, the microbial flora forming the slime, the allowable scale, It can be set arbitrarily in consideration of the amount of adhesion and the like.

When water enters the main body member for some reason during the detection period of the scale or the slime, the water leak sensor 1A, 3A detects this, and the water leak sensor 1A, 3A detects the water. Since the energization is immediately stopped, burning or failure of the resistance temperature detectors 1 and 3 due to a short circuit is prevented. Further, since the occurrence of water leakage is displayed on the display units 1C and 3C and an alarm is generated, it is possible to prevent an accident such that the devices 2 and 4 sink to the bottom of the water due to a decrease in buoyancy and measurement becomes impossible. it can.

The temperature measuring resistor is washed at an appropriate time. In this case, if the scale or slime adherence detection device of the present invention detects the adherence of scale and / or slime, if the system is to be washed with a scale remover or a slime remover, the water supply system may be used. Since the RTD is washed with the scale remover and the slime remover, it is not necessary to separately wash the RTD.

In the above embodiment, both the scale and the slime are detected. However, only one of the scale and the slime adhesion detecting devices 2 and 4 is installed to detect only one of the scale and the slime. Is also good.

[0053]

As described in detail above, according to the scale or slime adhesion detecting device of the present invention, it is relatively small and can be directly installed at any place in an actual process. Scale deposition and / or slime deposition can be continuously detected online. It becomes possible to inject medicine more accurately as described above. Since the temperature measuring resistor is surrounded by the surrounding body, the detection accuracy of the adhesion of the scale or the slime is high, and the durability of the temperature measuring resistor is also good. Therefore, it is possible to accurately grasp the scale and / or slime adhesion state of the water system, and to reliably prevent the adhesion failure.

This is a scale or slime adhesion detecting device having such an excellent effect as described above. Further, it is possible to prevent accidents such as failure, burnout, or measurement failure of the resistance thermometer due to breakage of the main body member. A highly reliable scale or slime deposit detection device is provided.

[Brief description of the drawings]

FIG. 1 is a system diagram showing an embodiment of a scale or slime adhesion detecting device of the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is a block diagram of a scale or slime detection system.

FIG. 4 is a block diagram of a main part of the detection system of FIG. 3;

FIG. 5 is a sectional view showing an example of mounting an electrode type water leak sensor.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 first temperature measuring resistor 1A water leak sensor 1B water leak detecting unit 1C display unit 2 scale adhesion detecting device 2A temperature measuring unit 2B determining unit 3 second temperature measuring resistor 3A water leak sensor 3B water leak detecting unit 3C Display unit 4 Slime adhesion detector 4A Temperature measurement unit 4B Judgment unit 5 Display unit 20 Body member 21 Sensor mounting member 22 Resistance temperature detector 23 Enclosure 26 Electromagnetic float sensor 27 Shaft 28 Float 40 Water leak sensor 41 Sponge 42, 43 electrode

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-96644 (JP, A) JP-A-3-27547 (JP, A) JP-A-7-208804 (JP, A) 62253 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) G01N 25/18 JICST file (JOIS)

Claims (4)

(57) [Claims] 1. A float sensor is mounted on a water surface.
A hollow main body member that can be floated, a sensor mounting member mounted on the main body member, a temperature measuring resistor detachable from the sensor mounting member, an enclosure surrounding the temperature measuring resistor, A scale or slime adhesion detecting device comprising a water leak sensor provided in a hollow portion of a main body member. 2. A float sensor is mounted on the water surface.
A hollow main body member that can be floated, and the main body member
And a sensor mounting member mounted on the
Detachable resistance thermometer and surrounding surrounding the resistance thermometer
Body and a water leak sensor provided in a hollow portion of the body member
A slime adhesion detection device comprising:
The value of the constant current that flows through the resistor can be switched
A slime adherence detecting device characterized by comprising means. (3)A float sensor is attached to the surface of the water
A hollow main body member that can be floated, and the main body member
And a sensor mounting member mounted on the
Detachable resistance thermometer and surrounding surrounding the resistance thermometer
Body and a water leak sensor provided in a hollow portion of the body member
The scale adhesion detection device is equipped with
A method for detecting adhesion, The amount of current supplied to the resistance thermometer is determined by the temperature of the resistance thermometer.
Is set in the range of 60 to 100 ° C.
Scale adhesion detection method. (4)A float sensor is attached to the surface of the water
A hollow main body member that can be floated, and the main body member
And a sensor mounting member mounted on the
Detachable resistance thermometer and surrounding surrounding the resistance thermometer
Body and a water leak sensor provided in a hollow portion of the body member
The slime adhesion detection device comprising
A method for detecting adhesion, The amount of current supplied to the resistance thermometer is determined by the temperature of the resistance thermometer.
Is set in the range of 30 to 37 ° C.
Slime adhesion detection method.