JPH07103932A - Measuring apparatus for ph provided with self-diagnostic function and measuring method for ph using the apparatus - Google Patents

Abstract

PURPOSE:To check the deviation of an inner-liquid-pressurization pressure from a set value and the excessive outflow of an inner liquid when the pressure of a liquid to be detected is lowered largely in a pH measuring apparatus which is provided with a glass electrode and with a pressurization inner-liquid-type comparison electrode. CONSTITUTION:An inner-liquid-pressure detection means 32 for a comparison electrode and an inner-liquid-amount detection means 34 for the comparison electrode are installed at an inner-liquid storage container 12. In addition, an alarm-signal generation means 30 which is connected to both detection means 32, 34 is installed. Then, when an inner-liquid pressure detected by the inner- liquid-pressure detection means 32 becomes a set value or lower and when an inner-liquid amount detected by the inner-liquid-amount detection means 34 becomes a set value or lower, the alarm-signal generation means 35 generates an alarm signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is provided with a glass electrode and a pressurized internal liquid type reference electrode, and can be used for processes, sewage, drainage, etc.
The present invention relates to a pH measuring device with a self-diagnosis function, which is suitably used as an outdoor pH measuring device for measuring H, and a pH measuring method using this device.

[0002]

2. Description of the Related Art Conventionally, pH of process, sewage, waste water, etc.
As an outdoor-installed pH measuring device for measuring, a device equipped with a glass electrode and a pressurized internal liquid type reference electrode is often used. This pH measuring device has, for example, the configuration shown in FIG.

In the pH measuring device 2 of FIG. 2, 4 is a glass electrode, 6 is a pressurized internal liquid type reference electrode, 8 is a liquid junction of the reference electrode 6, 10 is an internal liquid (KCl solution) of the reference electrode 6, 1
Reference numeral 2 is an internal liquid storage container connected to the reference electrode 6 via the connecting pipe 14, 16 is a supplementary internal liquid stored in the storage container 12, 18 is a pressurizing port formed in the storage container 12, and 20 is The pressurizing means for pressurizing the replenishing internal liquid 16 in the storage container 12 and the internal liquid 10 in the comparison electrode 6 from the pressurizing port 18 is shown.

As the pressurizing means 20, for example, instrumentation air, a manual pump, etc. are used, and usually, the pressure inside the storage container 12 is higher than the maximum pressure of the test liquid by about 0.3 to 0.5 Kgf / cm ² . Internal liquid 16 for replenishing the liquid and internal liquid 1 in the reference electrode 6
Press 0. At this time, when the pressure is applied by the instrumentation air, the pressure is continuously applied to the inside of the storage container 12. Also, when pressurizing with a manual pump,
After applying a pressure to the inside of the storage container 12, the storage container 12 is closed.

In the pH measuring device 2 of FIG. 2, the internal liquid 16 is put in the storage container 12, and the internal liquid 16 is connected to the connecting pipe 1.
4 into the reference electrode 6 and the liquid junction 8
The measurement is performed while causing a small amount of the internal liquid 10 to flow into the test liquid by the pressure difference (difference between the internal liquid pressure and the test liquid pressure) due to the pressurizing means 20 or the like. As a result, even if the liquid junction 8 of the reference electrode 6 is a test liquid that is likely to be clogged, the internal liquid 10 is forcibly discharged from the liquid junction 8 and stable measurement is performed.

In the pH measuring device equipped with the glass electrode and the pressurized internal liquid type reference electrode as shown in FIG. 2, the internal liquid is kept at a constant pressure in accordance with the pressure of the test liquid in order to ensure the outflow of the internal liquid. Pressurize with. Therefore, the internal liquid pressure is monitored by the pressure gauge.

[0007]

In a pH measuring device equipped with a glass electrode and a pressurized internal liquid type reference electrode, when the pressure of the test liquid becomes unexpectedly low during measurement, the test liquid is applied at a constant pressure. If you continue to press, the internal liquid will suddenly flow out. At this time, when the internal liquid is pressurized by the manual pump, the internal liquid pressure does not immediately decrease even if the test liquid pressure decreases. Further, when the pressure is applied by the instrumentation air, the decrease in the test liquid pressure does not affect the internal liquid pressure at all. Therefore, in a pH measuring device equipped with a glass electrode and a pressurized internal liquid type reference electrode, it is necessary to simply monitor the internal liquid pressure as in the conventional case so that the internal liquid pressurization pressure may deviate from the set value or the internal liquid may suddenly change. The present inventors have found that it is not possible to check for such a spill. Hereinafter, this point will be described.

FIG. 3 shows an example of fluctuation of the pressure of the test liquid in the fermentation process. As can be seen from FIG. 3, the zero in the test solution pressure standby-standard solution calibration phase, 2 Kgf / cm ² in sterile stage, the fermentation measures 0.5 Kgf / cm ^2, becomes zero at the end-wait step, pH The test solution pressure is 0.5 during measurement
It fluctuates greatly in the range of up to ² Kgf / cm ² .

When the pH of the test liquid shown in FIG. 3 is measured by a pH measuring device equipped with a glass electrode and a pressurized internal liquid type reference electrode, the differential pressure between the internal liquid and the test liquid is 0.5 Kgf / The maximum pressure of the test liquid is ² Kgf / cm ² , and the pressure of the internal liquid is usually set to 2.5 Kgf / cm ² when the guideline of the internal liquid outflow rate at cm ² is 1 ml / day. It Then, when the pressure of the test solution is ² Kgf / cm ² (sterilization stage), the following formula (2.5-2) × (1 / 0.5) = 1 ml / day, 1 ml / day It becomes the internal liquid consumption.

However, when the pressure of the test liquid fluctuates to 0.5 Kgf / cm ² (during fermentation measurement), the differential pressure between the internal liquid and the test liquid is directly proportional to the outflow amount of the internal liquid. From the following formula (2.5-0.5) × (1 / 0.5) = 4 ml / day, the internal liquid consumption is 4 ml / day, and the outflow amount of the internal liquid increases four times.

When the pH of a test liquid whose pressure fluctuates during such pH measurement is measured, if the pressure of the test liquid greatly decreases, the differential pressure between the internal liquid and the test liquid increases, and Since the liquid suddenly flows out, the internal liquid may disappear from the reference electrode and measurement may not be possible.

In addition to the fermentation process, as the test liquid whose pressure fluctuates during pH measurement, the test liquid whose pressure continuously increases or decreases during measurement as shown in FIG. 4 or as shown in FIG. There is a test liquid in the production plant that has a high pressure during the daytime when the production output is large and has a low pressure during the nighttime when the production output is small. When measuring the pH of the test liquid as shown in FIGS. 4 and 5, the same problem as in the measurement of the test liquid shown in FIG. 3 occurs.

The present invention has been made in view of the above circumstances, and checks the deviation of the internal liquid pressurization pressure from the set value and the excessive outflow of the internal liquid when the pressure of the test liquid greatly decreases. It is an object of the present invention to provide a pH measuring device capable of performing the above.

[0014]

Means and Actions for Solving the Problems The present inventors have
In order to achieve the above object, various investigations were performed, and when the pH of a test liquid with varying pressure was measured using a pH measuring device with a pressurized internal liquid type reference electrode, when the test liquid pressure decreased significantly. Since the differential pressure between the internal liquid and the test liquid becomes large and the internal liquid suddenly flows out, check the differential pressure between the internal liquid and the test liquid, and make sure that the differential pressure is always constant. By controlling the pressurization pressure of the internal liquid, it was first conceived that it is possible to prevent the internal liquid from flowing out too much.

As a result of further investigations by the present inventors, it is difficult to measure the pressure of the test liquid by the method of checking the differential pressure between the internal liquid and the test liquid, and the differential pressure However, the internal liquid pressure detection means and the internal liquid amount detection means of the reference electrode are provided, and the pressure detection means constantly monitors the pressure fluctuation of the internal liquid. The internal liquid amount detection means constantly monitors the decrease of the internal liquid amount, and when the internal liquid pressure is out of the predetermined level and the alarm is issued when the internal liquid amount is out of the predetermined level, the internal liquid is detected by a simple means. The inventors have found that it is possible to properly check the deviation of the liquid pressurization pressure from the set value and the excessive outflow of the internal liquid, and have completed the present invention.

Therefore, according to the present invention, in a pH measuring device equipped with a glass electrode and a pressurized internal liquid type reference electrode, an internal liquid pressure detecting means of the reference electrode, an internal liquid amount detecting means of the reference electrode, and A pH measuring device with a self-diagnosis function, comprising: an alarm signal generating means connected to both detecting means.

The present invention also provides a pH measuring method characterized in that the pH of a test liquid whose pressure fluctuates during pH measurement is measured by using the above-mentioned pH measuring device with a self-diagnosis function. In this case, examples of the test liquid whose pressure fluctuates during pH measurement that can be measured by the pH measuring method of the present invention include a test liquid in a fermentation process.

In the present invention, the types of the glass electrode and the pressurized internal liquid type reference electrode are not limited, and known ones can be used. In this case, as the glass electrode and the reference electrode, separate ones may be used in combination, or a composite electrode in which these are integrated may be used.

There is no limitation on the types of the internal liquid pressure detecting means, the internal liquid amount detecting means, and the alarm signal generating means. For example, the internal liquid pressure detecting means may be a microswitch contact type built-in switch pressure gauge, a reference electrode, or the like. A float type level switch or the like can be used as the internal liquid amount detecting means, and an alarm contact signal output circuit or the like can be used as the alarm signal generating means.

The internal liquid pressure detecting means and the internal liquid amount detecting means are provided so as to detect the internal liquid pressure and the internal liquid amount in the storage container when the internal liquid storage container is connected to the reference electrode. . Further, when the internal liquid storage container is not connected to the reference electrode, it is provided so as to detect the internal liquid pressure and the internal liquid amount in the reference electrode holder.

The pH measuring device with self-diagnosis function of the present invention is provided with other self-diagnosis means such as a glass film crack detection means and a liquid junction clogging detection means as electrode accident countermeasure means, if necessary. The self-diagnosis means may be connected to the alarm signal generating means.

When the pH of the test liquid whose pressure fluctuates is measured using the pH measuring device with the self-diagnosis function of the present invention, the pressure of the test liquid decreases and the differential pressure between the internal liquid and the test liquid increases. Then, the internal liquid suddenly flows out. At this time, when the internal liquid is pressurized by the manual pump, the internal liquid pressure does not immediately decrease even if the test liquid pressure decreases. Further, when the internal liquid is pressurized with instrumentation air, the decrease in the test liquid pressure does not affect the internal liquid pressure at all. Therefore, in the measuring device of the present invention, the alarm signal generating means is set to generate an alarm signal both when the internal liquid pressure falls below a predetermined level and when the internal liquid amount falls below a predetermined level.

As a result, the manager of the measuring device appropriately checks the deviation of the internal liquid pressurization pressure from the set value and the excessive outflow of the internal liquid, and replenishes the internal liquid and adjusts the internal liquid pressurization pressure. It becomes possible to do it in a timely manner.

When pressurizing the internal liquid with instrumentation air, the pressurization pressure of the internal liquid may become unnecessarily high depending on the condition of the valve or the like. In the pH measuring device with the self-diagnosis function of the present invention, in order to detect such a pressure increase, it is possible to set the alarm signal generating means to generate an alarm signal when the internal liquid pressure exceeds a predetermined level. it can.

[0025]

EXAMPLES The present invention will now be specifically described with reference to examples, but the present invention is not limited to the following examples.

FIG. 1 shows a pH measuring device with a self-diagnosis function according to an embodiment of the present invention. In FIG. 1, the same components as those of the pH measuring device of FIG. 2 are designated by the same reference numerals and the description thereof will be omitted.

PH measuring apparatus 30 with self-diagnosis function of this embodiment
In the internal liquid storage container 12, the internal liquid pressure detecting means 32 of the reference electrode and the internal liquid amount detecting means 34 of the reference electrode are installed, and the alarm signal generating means 36 connected to the both detecting means 32, 34 is provided. It is provided. A micro switch contact type switch built-in pressure gauge is used as the internal liquid pressure detecting means 32, and a float type level switch is used as the internal liquid amount detecting means 34.

PH measuring device 30 with self-diagnosis function of this embodiment
Is when the internal liquid pressure of the reference electrode detected by the internal liquid pressure detection means 32 is less than or equal to the set value and when the internal liquid pressure of the reference electrode detected by the internal liquid amount detection means 34 is less than or equal to the set value. An alarm signal is generated from the alarm signal generating means 36, respectively. Thereby, the administrator of the measuring device can check the deviation of the internal liquid pressurization pressure from the set value and the excessive outflow of the internal liquid.

[0029]

As described above, according to the pH measuring device with the self-diagnosis function of the present invention, even when the pH of the test liquid whose pressure changes is measured, In addition to being able to respond immediately to the deviation, it is possible to check if the internal liquid has flowed out too much when the pressure of the test liquid has dropped significantly, and it is possible to properly perform maintenance management of the internal liquid with a simple means. . Further, according to the pH measuring method of the present invention, it is possible to stably measure the pH of the test liquid in which the pressure fluctuates.

[Brief description of drawings]

FIG. 1 is a schematic view showing a pH measuring device with a self-diagnosis function according to an embodiment of the present invention.

FIG. 2 is a graph showing an example of pressure fluctuation during pH measurement of a test liquid.

FIG. 3 is a graph showing an example of pressure fluctuation during pH measurement of a test liquid.

FIG. 4 is a graph showing an example of pressure fluctuation during pH measurement of a test liquid.

FIG. 5 is a schematic view showing an example of a conventional pH measuring device equipped with a glass electrode and a pressurized internal liquid type reference electrode.

[Explanation of symbols]

 4 glass electrode 6 pressurized internal liquid type reference electrode 8 liquid junction 10 internal liquid 12 internal liquid storage container 16 replenishing internal liquid 20 pressurizing means 30 pH measuring device with self-diagnosis function 32 internal liquid pressure detecting means 34 internal liquid volume Detecting means 36 Alarm signal generating means

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Taiichi Asano 4-13-14 Kitacho, Kichijoji, Musashino-shi, Tokyo Inside Electrochemical Instruments Co., Ltd. (72) Inventor Satoshi Ito 4-chome, Kichijoji, Musashino-shi, Tokyo No. 14 Electrochemical Instrument Co., Ltd. (72) Inventor Masao Mizuno 4-13-14, Kichijoji Kitamachi, Musashino City, Tokyo Electrochemical Instrument Co., Ltd.

Claims (2)

[Claims] 1. A pH measuring device comprising a glass electrode and a pressurized internal liquid type reference electrode, wherein an internal liquid pressure detecting means of the comparing electrode, an internal liquid amount detecting means of the comparing electrode, and both detecting means. A pH measuring device with a self-diagnosis function, comprising a connected alarm signal generating means. 2. The p of a test liquid whose pressure fluctuates during pH measurement.
A pH measuring method, wherein H measurement is performed by the pH measuring device with a self-diagnosis function according to claim 1.