JP6770216B1 - Residual chlorine automatic analyzer - Google Patents

Abstract

Provided is an automatic residual chlorine analyzer with improved maintenance efficiency as compared with the prior art. The residual chlorine automatic analyzer 1 is installed in the measurement cell 11 for measuring the residual chlorine concentration in the liquid to be analyzed, and chlorine for removing biological obstacles adhering to the measurement cell 11 on the upstream side of the measurement cell. A chlorine generating section C that intermittently generates chlorine is provided.

Description

The present invention relates to an automatic residual chlorine analyzer. More specifically, the present invention relates to an automatic residual chlorine analyzer for measuring the residual chlorine concentration in seawater near the outlet of a power plant.

Seawater electrolytic chlorine injection is widely practiced as a countermeasure against sessile organisms such as barnacles and mussels that adhere to the seawater system of seawater utilization plants such as thermal power plants and nuclear power plants, and biofilms.

For example, in Patent Document 1, sodium hypochlorite is produced by electrolyzing natural seawater, and an electrolytic solution containing the sodium hypochlorite is injected into the intake of seawater to prevent the adhesion of marine organisms. Discloses the technology used for.

Japanese Patent No. 4932529

When injecting chlorine into the sea area, it is necessary to maintain the environmental conservation agreement value at the outlet, so an automatic residual chlorine analyzer is installed at the outlet for continuous monitoring. However, since seawater is constantly flowing inside the automatic residual chlorine analyzer, attached organisms such as barnacles and mussels and biofilms adhere to the automatic residual chlorine analyzer itself, and the inside of the automatic residual chlorine analyzer There are problems that the path of the barnacle is blocked, the flow rate of seawater is reduced, and the biofilm adheres to the surface of the measurement electrode, resulting in a decrease in measurement accuracy.

At present, the automatic residual chlorine analyzer is cleaned about once every 1 to 2 weeks, but it is necessary to clean the entire complicated route, which requires a great deal of labor.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an automatic residual chlorine analyzer with improved maintenance efficiency as compared with the prior art.

The present invention is an automatic residual chlorine analyzer, which measures a measuring cell for measuring the residual chlorine concentration in the liquid to be analyzed, and a biological obstacle installed on the upstream side of the measuring cell and adhering to the measuring cell. The present invention relates to an automatic residual chlorine analyzer, comprising a chlorine generating unit that intermittently generates chlorine for removal.

Further, it is preferable that the analysis target liquid is a liquid containing sodium chloride, and the chlorine generating unit is an electrolytic cell that generates the chlorine by electrolyzing the analysis target liquid.

Further, it is preferable that the chlorine generating unit produces residual chlorine having a concentration of 0.5 mg / L or more.

Moreover, it is preferable that the liquid to be analyzed is seawater.

It is possible to provide an automatic residual chlorine analyzer with improved maintenance efficiency as compared with the conventional technology.

It is an external view of the residual chlorine automatic analyzer which concerns on embodiment of this invention. It is the schematic of the functional block of the residual chlorine automatic analyzer and the flow path of the liquid to be analyzed which concerns on embodiment of this invention. It is a figure which shows the flow of seawater and the place where the test piece is installed in the Example of this invention. It is a figure which shows the flow of seawater and the place where the test piece is installed in the Example of this invention. It is a figure which shows the flow of seawater and the place where the test piece is installed in the Example of this invention. It is an image which shows the test piece as a test result in an Example of this invention. It is an image which shows the test piece as a test result in an Example of this invention. It is an image which shows the test piece as a test result in an Example of this invention. It is an image which shows the test piece as a test result in an Example of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Structure of 1 Embodiment]
FIG. 1 is an external view of an automatic residual chlorine analyzer according to an embodiment of the present invention. The appearance of the automatic residual chlorine analyzer shown in FIG. 1 is merely an example, and is not limited thereto.

As shown in FIG. 1, the residual chlorine automatic analyzer 1 according to the present embodiment mainly includes a measurement cell 11, a sampling tank 12, a monitor 15, a sensor 16, an intake tank 21, a hose 22, a first pipe 31, and a second. It includes a pipe 32 and a third pipe 33, which are fixed to the columns 30.

More specifically, the intake tank 21, the measurement cell 11, the sampling tank 12, and the monitor 15 are fixed to the support column 30 in this order from the bottom, and the first pipe 31 from the intake tank 21 via the hose 22 is connected to the sampling tank 12. Connected to. Further, the second pipe 32 is connected from the sampling tank 12 to the measurement cell 11, and the third pipe 33 is connected from the sampling tank 12 to the intake tank 21. The first pipe 31, the second pipe 32, and the third pipe 33 are fixed to the support column 30 in a parallel state.

The sampling tank 12 includes an electrolytic solution tank 121, a test water tank 122, and a surplus water tank 123. The first pipe 31 and the second pipe 32 are connected to the test water tank 122, and the third pipe 33 is connected to the surplus water tank 123.

Further, a sensor 16 for detecting the residual chlorine concentration is connected to the residual chlorine concentration monitor 15, and the tip of the sensor 16 is immersed in the residual chlorine concentration analysis target liquid contained in the measurement cell 11.

Hereinafter, the functions of each component will be described according to the flow path of the liquid to be analyzed for the residual chlorine concentration. In the following, the description will be made on the premise that the liquid to be analyzed is seawater, but this is an example and is not limited as long as the liquid to be analyzed contains sodium chloride.

The water intake tank 21 is, for example, a tank for storing seawater taken from the water outlet of a power plant by an water intake pump. The seawater stored in the intake tank 21 is pumped up to the test water tank 122 of the sampling tank 12 via the hose 22 and the first pipe 31 by a pump (not shown).

The test water tank 122 includes an electrolytic cell (not shown), and the electrolytic cell intermittently electrolyzes seawater to produce sodium hypochlorite. The concentration of residual chlorine produced is preferably 0.5 mg / L or more. Furthermore, the concentration of residual chlorine produced is preferably 0.5 mg / L or more and 20 mg / L or less, but is not limited thereto. The frequency of electrolysis by the electrolytic cell may be, for example, once every three hours for about 10 minutes. At this time, the current value of the electrolytic cell is adjusted so that the residual chlorine concentration measured by manual analysis in the water intake tank 21 is 1 mg / L.

Seawater containing sodium hypochlorite produced by electrolysis of the electrolytic cell flows into the measurement cell 11 via the second pipe 32. When seawater containing chlorine flows into the measurement cell 11, the attached organisms such as barnacles and mussels and the biofilm in the measurement cell 11 are washed and their generation is suppressed.

Normally, the seawater to be analyzed for the residual chlorine concentration flows into the measurement cell 11 via the second pipe 32 without being electrolyzed. In the measurement cell 11, the sensor 16 measures the residual chlorine concentration in seawater, and the measured value is displayed on the monitor 15.

When the flow rate of the seawater pumped up to the test water tank 122 is excessive, the surplus seawater flows out to the surplus water tank 123 and then is discharged to the intake tank 21 via the third pipe 33.

The electrolytic solution tank 121 stores the electrolytic solution (the liquid inside the measuring electrode). Examples of the components of the electrolytic solution include potassium chloride.

FIG. 2 is a schematic view mainly showing the flow path of the liquid to be analyzed in the residual chlorine automatic analyzer 1. Hereinafter, although it will be partially repeated, the flow of the liquid to be analyzed will be described with reference to FIG. In FIG. 2, the same reference numerals are used for the same components as those shown in FIG. 1, and detailed description of their functions will be omitted.

In FIG. 2, an inflow water line L1, a runoff water line L2, and a surplus water line L3 are provided between the sampling tank 12 and the intake tank 21 as lines through which the liquid to be analyzed flows.

The inflow water line L1 is a line in which the liquid to be analyzed as the inflow water W1 that is pumped from the intake tank 21 by the pump P and flows into the test water tank 122 flows. The inflow water line L1 includes a filter F and a first valve V1.

The filter F is a device that filters the inflow water W1 pumped from the intake tank 21.
The first valve V1 is a valve that adjusts the flow rate of the inflow water W1 after being filtered by the filter F to the test water tank 122.

The inflow water line L1 corresponds to the hose 22 and the first pipe 31 in FIG.

The effluent line L2 is a line through which the effluent W2 whose residual chlorine concentration is measured in the measurement cell flows while flowing out from the test water tank 122. The effluent line L2 includes a first effluent line L21 and a second effluent line L22. Further, the runoff water W2 includes the first runoff water W21 and the second runoff water W22.

The first effluent line L21 is a line through which the liquid to be analyzed as the first effluent W21 flows out from the test water tank 122 to the measurement cell 11. When electrolyzed by the electrolytic cell C provided in the test water tank 122, the first runoff water W21 contains chlorine. The first runoff line L21 includes a second valve V2.

The second valve V2 is a valve that adjusts the flow rate of the first outflow water W21 flowing out of the test water tank 122 to the measurement cell 11.

The second effluent line L22 is a line for storing the second effluent W22 overflowing from the measurement cell 11 in the intake tank 21.
The runoff line L2 corresponds to the second pipe 32 in FIG.

The surplus water line L3 is a line through which the surplus water W3 flowing out from the surplus water tank 123 to the intake tank 21 flows. The surplus water line L3 includes a third valve V3.

The third valve V3 is a valve that adjusts the flow rate of the surplus water W3 flowing out of the surplus water tank 123 to the intake tank 21.
The surplus water line L3 corresponds to the third pipe 33 in FIG.

The water to be analyzed stored in the intake tank 21 is pumped into the inflow water line L1 as the inflow water W1 by the pump P, filtered by the filter F, and then stored in the test water tank 122 of the sampling tank 12.

The inflow water W1 stored in the test water tank 122 is intermittently electrolyzed by the electrolytic cell C in some cases, and then becomes the first outflow water W21 by osmotic pressure, and then enters the measurement cell 11 via the first outflow water line L21. Be housed.

The residual chlorine concentration of the first runoff water W21 housed in the measurement cell 11 is measured by the sensor 16, and the measured value is displayed on the monitor 15. The second effluent W22 overflowing from the measurement cell 11 is stored in the intake tank 21 via the second effluent line L22.

Further, the surplus water W3 surplus in the test water tank 122 is stored in the surplus water tank 123 and then discharged to the intake tank 21 via the surplus water line L3.

According to the residual chlorine automatic analyzer according to the above embodiment, the following effects are achieved.

(1) As described above, the automatic residual chlorine analyzer according to the above embodiment is installed in the measurement cell 11 for measuring the residual chlorine concentration in the liquid to be analyzed and on the upstream side of the measurement cell 11 in the measurement cell 11. It includes an electrolytic cell C that intermittently produces chlorine for removing an obstacle derived from an attached organism.
This makes it possible to provide an automatic residual chlorine analyzer with improved maintenance efficiency as compared with the conventional technique.

(2) As described above, the liquid to be analyzed is a liquid containing sodium chloride, and the electrolytic cell C produces chlorine by electrolyzing the liquid to be analyzed.
This makes it possible to use the liquid to be analyzed itself for chlorine production.

(3) As described above, the electrolytic cell C produces residual chlorine having a concentration of 0.5 mg / L or more.
This makes it possible to clean the measurement cell 11 without imposing a great load on the environment.

(4) As described above, the liquid to be analyzed is seawater.
This makes it possible to measure the residual chlorine concentration of seawater taken from the outlet of a power plant, for example.

[2 Control test]
In order to confirm the cleaning effect of sodium hypochlorite produced by the automatic residual chlorine analyzer 1 according to the present embodiment, a slide glass as a test group and a slide glass as a control group are installed in the sampling tank 12. And a control test was conducted.

3A to 3C are views showing installation locations of both slide glasses. Further, FIGS. 4A to 4D are images of the slide glass as a test result. Hereinafter, the details of the control test method and the results thereof will be described with reference to FIGS. 3A to 3C and FIGS. 4A to 4D.

FIG. 3A is a structural view of the sampling tank 12 as viewed from above. The sampling tank has a first region in which seawater as the inflow water W1 flows in, a second region in which the surplus water W3 surplus in the first region flows in, and a third region in which the inflow water W1 is electrolyzed by the electrolytic cell C. , The fourth region accommodating the inflow water W1 after electrolysis, the fifth region in which the inflow water W1 from the fourth region is circulated to the sixth region described later, and the inflow water W1 as the outflow water W2 flow out to the measurement cell 11. It is divided into a sixth region to be operated.
Here, the first region, the second region, the fourth region, the fifth region, and the sixth region correspond to the test water tank 122, and the second region corresponds to the surplus water tank 123.

Further, FIG. 3B is a view of the BB plane viewed in the arrow direction in FIG. 3A, and FIG. 3C is a view of the CC plane viewed in the arrow direction in FIG. 3A.

The details of the flow of the inflow water W1, the outflow water W2, and the surplus water W3 are as follows.
The inflow water W1 flows into the first region from the inflow water line L1 (F1), and the surplus portion of the inflow water W1 exceeds the weir 151 and flows into the second region (F2). The inflow water W1 that does not exceed the weir 151 flows into the third region from the lower side of the weir 152 (F3). The inflow water W1 electrolyzed by the electrolytic cell C in the third region passes under the weir 153 and flows into the fourth region (F4). In order to adjust the water level in the fourth region, the inflow water W1 passing above the weir 154 flows into the second region (F5). On the other hand, in the fourth region, the inflow water W1 passing above the weir 155 flows into the fifth region (F6). The inflow water W1 that has flowed into the fifth region passes under the weir 156 and flows into the sixth region (F7). The inflow water W1 that has flowed into the sixth region flows out to the measurement cell 11 as the outflow water W2 via the first outflow water line L21 (F8). Further, the surplus water W3 flowing from the first region to the second region and the surplus water W3 flowing into the second region from the fourth region are discharged by the surplus water line L3 (F9).

Further, as shown in FIGS. 3A to 3C, a test piece T1 as a test group is installed on a wall facing the first region in the sixth region, and a wall facing the sixth region in the first region. A test piece T2 was installed as a control group in the water, and the follow-up was observed while electrolyzing the inflow water W1 by the electrolytic cell C for 10 minutes every 3 hours. Here, while chlorine produced by electrolysis by the electrolytic cell C in the third region flows into the sixth region, the chlorine does not flow into the first region.

FIG. 4A is an image of the test piece installed from June 19, 2018 to July 13, 2018. The left side is the test piece of the test group, and the right side is the test piece of the control group. As is clear from FIG. 4A, the amount of dirt and attached organisms adhering to the test piece of the test group is smaller than that of the test piece of the control group.

FIG. 4B is an image of the test piece installed from July 27 to August 21, 2018. The right side is the test piece of the test plot, and the left side is the test piece of the control plot. As is clear from FIG. 4B, the amount of dirt and attached organisms adhering to the test piece of the test group is smaller than that of the test piece of the control group.

FIG. 4C is an image of the test piece installed from October 10, 2018 to November 9, 2018. The right side is the test piece of the test group, and the left side is the test piece of the control group. As is clear from FIG. 4C, the amount of dirt and attached organisms adhering to the test piece of the test group is smaller than that of the test piece of the control group.

FIG. 4D is an image of the test piece installed from November 9, 2018 to December 20, 2018. The left side is the test piece of the test group, and the right side is the test piece of the control group. As is clear from FIG. 4D, the amount of dirt and attached organisms adhering to the test piece of the test group is smaller than that of the test piece of the control group.

[3 Modification example]
Although the above-described embodiment is a preferred embodiment of the present invention, the scope of the present invention is not limited to the above-described embodiment, and various modifications are made without departing from the gist of the present invention. Can be implemented.

In the above embodiment, it is assumed that the electrolytic cell C electrolyzes the analysis target liquid containing sodium chloride to generate chlorine, but the present invention is not limited to this. For example, chlorine may be generated by automatically and intermittently charging a chlorine-based chemical into the sampling tank 12.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. Further, the effects described in the present embodiment merely list the most preferable effects arising from the present invention, and the effects according to the present invention are not limited to those described in the present embodiment.

1 Residual chlorine automatic analyzer 11 Measurement cell 12 Sampling tank 15 Monitor 16 Sensor 21 Water intake tank 22 Hose C Electrolysis cell

Claims (3)

Residual chlorine automatic analyzer
A measurement cell that measures the residual chlorine concentration in the liquid to be analyzed,
A chlorine generating unit that is installed on the upstream side of the measuring cell and intermittently generates chlorine for removing biological obstacles adhering to the measuring cell.
With
The liquid to be analyzed is a liquid containing sodium chloride.
The liquid to be analyzed after measuring the residual chlorine concentration in the measuring cell is supplied to the chlorine generating unit.
The chlorine generator, the pre-Symbol analyte solution produces the chlorine by electrolyzing upstream of the measuring cell, residual chlorine automatic analyzer supplied to the measurement cell. The automatic residual chlorine analyzer according to claim 1, wherein the chlorine generating unit produces residual chlorine having a concentration of 0.5 mg / L or more. The automatic residual chlorine analyzer according to claim 1 or 2, wherein the liquid to be analyzed is seawater.