CN110998307B - Management system of water treatment equipment - Google Patents

Abstract

A management system for a water treatment facility is provided with a 1 st storage means for storing a correlation between conductivity and pH, and a management means for obtaining a theoretical pH value based on the correlation between the conductivity measured by a conductivity meter and the correlation stored in the 1 st storage means, and for issuing a signal for prompting correction of the pH meter when the theoretical pH value and a measured value of pH detected by the pH meter deviate from a predetermined value or more.

Description

Management system of water treatment equipment

technical field

The present invention relates to a management system of water treatment equipment such as a boiler water supply system. More specifically, the present invention relates to a management system for water treatment equipment that manages using a preset correlation between conductivity and pH under arbitrary predetermined temperature conditions.

Background technique

Patent Document 1 discloses that the management center of the equipment management system regularly collects equipment operation information of water treatment equipment and manages the operation status. Patent Document 1 discloses detailed analysis of the operating state of water treatment facilities based on facility operation information and analysis results of treated water while referring to reference information stored in a database. Patent Document 1 discloses that advice information, maintenance information, and the like on operating conditions that are helpful for operating water treatment facilities are created and presented on the water supply treatment facility side.

It is an important issue to confirm the accuracy of on-site instruments to improve the water treatment effect. In the case of water treatment equipment for power generation boilers, pH is an important management item, and its scope of application is also described in JIS B8223:2015. Patent Document 2 describes a water supply management device for a boiler that performs mutual calibration using a plurality of pH meters, or observes the correlation of pH values converted by conductivity meters. The management device of Patent Document 2 needs to prepare a plurality of pH meters and compare their values. The problem with the management device of Patent Document 2 is that the pH value itself fluctuates due to the temperature of the sample, thereby causing a drift in the pH value. It is very difficult to adjust the amount of cooling water to keep the temperature of the sample water on site constant.

prior art literature

Patent documents:

Patent Document 1: Japanese Patent No. 3624941;

Patent Document 2: Japanese Unexamined Patent Publication No. 2002-349804.

Contents of the invention

It is an object of the present invention to provide a management system for water treatment facilities that can prevent water treatment management in a state where pH meter deviation and calibration deviation are not eliminated, and can perform stable water treatment management.

The water treatment facility management system of the first invention is a water treatment facility management system having a pH meter and a conductivity meter, and is characterized in that it includes: a first storage mechanism for storing the correlation between conductivity and pH; a second storage mechanism , storing the correlation between pH and water temperature; and the management agency, based on the electrical conductivity measured by the conductivity meter and the correlation stored in the first storage mechanism, to obtain a theoretical pH value, based on the correlation stored in the second The correlation between the storage mechanism and the water temperature converts the pH value detected by the pH meter into a pH value at a specified temperature, and sends a signal to urge the pH meter to calibrate if the theoretical pH value and the converted pH value deviate from the specified value or more.

The water treatment facility management system of the second invention is a water treatment facility management system having a conductivity meter, characterized in that it includes: a storage mechanism for storing the correlation between conductivity and pH under predetermined temperature conditions; and calculating the pH The means for obtaining the pH value is based on the correlation between the conductivity measured by the conductivity meter and the correlation stored in the storage means.

In one aspect of this invention, the said predetermined temperature is 25 degreeC.

In 1 aspect of this invention, the said water treatment facility targets boiler water supply.

In one aspect of the present invention, the management unit transmits a recommendation signal including adjustment of injection amount of medicine or adjustment of discharge amount.

According to the present invention, when the pH converted to the pH under the predetermined temperature condition deviates from the pH value obtained from the conductivity by more than the specified value, a display prompting correction is performed, or the pH is estimated from the conductivity, thereby preventing errors based on Water treatment management with a large pH measurement value realizes stable water treatment management.

Description of drawings

FIG. 1 is a block diagram showing an embodiment.

Fig. 2 is a graph showing the relationship between pH and conductivity.

FIG. 3 is a schematic diagram showing a control example.

Fig. 4 is a graph showing the relationship between pH and temperature.

Detailed ways

Embodiments will be described below with reference to the drawings. FIG. 1 shows an example of the management system of the water treatment facility of the present invention. In water treatment equipment (for example, water treatment equipment for power generation boilers) 1 , alkaline chemicals such as ammonia, neutral amines, and hydrazine are added and injected through a chemical injection device 2 .

A pH meter, a conductivity meter, a water temperature meter, and the like are provided as part of the field devices 3 for managing the water quality of the water treatment facility 1 , and these data are sent to a determination device (eg, PLC) 4 . The judging device 4 is provided with a judging unit 4a, a display unit 4b, and a transmitting unit 4c. The pH value measured by the pH meter is converted into a pH value at a predetermined temperature, and it is confirmed that the converted pH value does not match the theoretical pH value obtained from the conductivity. Deviation, at the same time, transmits the data to the management center 5. The information is accumulated in the management center 5, and if it is different from the previous one, it is compared with the phenomenon registered in the data analysis unit in advance, and the advice display unit 6 displays the adjustment of the injection amount of the chemical solution, the adjustment of the boiler water discharge amount, etc. suggestion. As the advice display unit 6, a personal computer, a portable terminal, or the like is used.

The judging unit 4a of the judging device 4 stores, for example, a pH-temperature relationship line shown in FIG. When the pH value deviates from the theoretical pH value calculated from the conductivity of the conductivity meter, the display unit 4 b displays a suggestion display to prompt correction, and the same content is also transmitted to the management center 5 . Accordingly, the same advice display is also performed on the advice display unit 6 via the management center 5 . This display can be sent by e-mail, or can be displayed on a specific WEB page, and can be obtained by visiting the WEB page.

When the pH meter on site has a large error in the measured pH value (deviation from the theoretical pH value calculated based on the conductivity of the conductivity meter) due to deterioration, damage, etc., the display unit 4b of the judging device 4 can be used to Displays the theoretical pH value converted from conductivity and transmits it to the configuration of the management center 5 .

The correlation line between the pH value and the conductivity may be a correlation line under temperature conditions such as 20°C and 30°C, but when considering boiler water management, it is preferable to set it to 25 so that it can comply with JIS B8223 (2015), for example. ℃ correlation line.

The conductivity measured by the conductivity meter is less affected by temperature (water temperature) than the pH value, so temperature conversion may not be performed, but in order to measure more accurately, it is preferable to use the temperature conversion function attached to the electrode, etc. Make corrections.

In this embodiment, as described above, the measured pH value of the pH meter is converted into a pH value at a predetermined temperature, and when the converted pH value deviates from the theoretical pH value obtained from the conductivity by a predetermined value or more, a correction instruction is displayed. . The predetermined value of the deviation is preferably a value selected from 0.1 to 0.5, for example, 0.3, preferably about 0.2.

In the suggested display, not only the display based on the pH meter and the conductivity meter, but also the results obtained by using a more minute measuring instrument can be included.

The signal for displaying a suggestion for pH meter calibration may be, for example, a signal transmitted with periodic data transmitted every hour, but is preferably transmitted without delay when the measured pH value deviates from the theoretical value by a predetermined value or more. In order to prevent a suggestion to prompt calibration during calibration of the pH meter, a calibration button may be provided, or a configuration may be provided so that a signal to prompt calibration is not issued within a predetermined period (for example, within 30 minutes).

Example

[Measurement Example 1]

Ammonia and various amines are used as pH regulators for boiler feed water. Thus, the pH and electrical conductivity of boiler feed water to which ammonia, 3-methoxypropylamine, or cyclohexylamine was added at various concentrations were measured at 25°C. The relationship between the two is shown in FIG. 2 (correlation line). As shown in Figure 2, corresponding to various pH regulators, the logarithmic value of conductivity has a linear relationship with pH. Therefore, when the drift of the pH measurement value caused by the pH meter (described later in Example 1) and the error caused by temperature (described later in Example 2) are large, the pH meter is corrected based on the conductivity. The measured value can eliminate or reduce the error.

Fig. 2 shows the correlation line when only one of each pH adjuster is added to the boiler feed water. However, when adding multiple amines and ammonia in combination, the correlation line is similarly obtained in advance, and the correlation line is calculated based on the correlation line Find the theoretical pH value in terms of conductivity.

[Comparative Example 1, Example 1]

FIG. 3 shows the results of investigations on boilers using ammonia for pH adjustment of boiler feed water.

The pH meters used in Comparative Example 1 and Example 1 have a characteristic that the measured pH value drifts to the negative side.

The results of Comparative Example 1 are shown on the left half of FIG. 3 . In Comparative Example 1, the pH meter was calibrated once a month as before, but the temperature conversion was not implemented. In this Comparative Example 1, the pH was not found to drift in the negative direction, but the amount of ammonia added was increased, so the pH (measured value of the pH meter) appeared to change at a constant value, but in fact, the ammonia concentration in the system became high, and there was concern. Ammonia corrosion in condenser.

The results of Example 1 are shown in the right half of FIG. 3 . As shown in the figure, when the method of the present invention is used, the pH is managed at 25°C converted from the conductivity, so the actual pH is kept constant for two months, and appropriate drug injection management is continued.

Based on the above, the usefulness of the method of estimating the pH value from the measured value of the conductivity based on the correlation line between the pH and the conductivity measured in advance was confirmed.

[Example 2]

The temperature of boiler feed water was changed in the range of 18 to 35°C, and the pH value was measured. The results are shown in Fig. 4 . As shown in Figure 4, there is a linear relationship between temperature and pH. Therefore, it is obvious that even the pH value measured at a temperature other than 25°C can be converted into a pH value at 25°C by using a conversion formula.

By performing drug injection control based on the pH value converted to 25°C, more appropriate adjustment of the drug injection amount can be performed. It should be noted that the conversion formula in FIG. 4 is as follows.

pH[at25°C]=pH[atM°C]+(M-25)×0.035

Although this invention was demonstrated in detail using the specific form, it is clear for those skilled in the art that various changes can be made without deviating from the intent and range of this invention.

This application is based on Japanese Patent Application No. 2017-172246 filed on September 7, 2017, the entire contents of which are incorporated herein by reference.

Description of reference symbols

1: Water treatment equipment;

4: Measuring device;

5: Management Center;

6: Recommended display section.

Claims (3)

1. A management system for a water treatment facility, which is provided with a pH meter and a conductivity meter, is characterized by comprising:

1, storing the correlation between the conductivity and the pH value;

a 2 nd storage mechanism for storing the correlation between the pH value and the water temperature; and

and a control means for obtaining a theoretical pH value based on the correlation between the electrical conductivity measured by the electrical conductivity meter and the water temperature stored in the 1 st storage means, converting the pH value detected by the pH meter into a pH value of 25 ℃ as a predetermined temperature based on the correlation between the water temperature and the electrical conductivity stored in the 2 nd storage means, and generating a signal for prompting the pH meter to correct when the theoretical pH value and the converted pH value deviate from a predetermined value selected from a range of 0.1 to 0.5 or more.

2. The management system of a water treatment apparatus according to claim 1, wherein said water treatment apparatus targets boiler feed water.

3. The management system of a water treatment apparatus according to claim 2, wherein said management means transmits an advice signal containing adjustment of an amount of injected chemical agent or adjustment of a discharge amount.

Images