JP4352367B2 - Electrode cleaning method and residual chlorine meter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrode cleaning method and a residual chlorine meter, and more particularly to an electrode cleaning method and a residual chlorine meter provided with a structure for cleaning an electrode used when measuring residual chlorine in water.
[0002]
[Prior art]
There are various residual chlorine meters in the prior art in which electrodes are cleaned.
[0003]
The structure for cleaning the electrode of the first specific example is a polarographic method using a rotating metal rod as shown in FIG. 2, and can rotate in glass beads and perform long-term stable measurement while performing continuous automatic cleaning. The container for flowing test water is divided into two rooms, the counter electrode 12 is arranged in one room 11a, and two electrodes, that is, the working electrode 13 and the other room 11b, The rotating electrode 14 is arranged facing the installed working electrode 13, and the bottom of the working electrode 13 provided in the other chamber 11 b is inclined, and the position corresponding to the tip portion of the rotating electrode 14 there. In this structure, a predetermined amount of glass beads 15 are spread.
[0004]
In the electrode having such a structure, since the rotating electrode 14 is rotating, the glass beads 15 in the test water 16 come into contact with the rotating electrode 14 to clean the electrode.
[0005]
As shown in FIG. 3, the structure for cleaning the electrode of the second specific example is a miniaturized structure in which the electrode 25 is fixed, the small glass beads 26 are moved by water flow, and hit against the gold electrode at the tip. It is. The structure is such that a narrow tube 22 for inputting the test water 16 is disposed in the container 21 for inputting the test water 16 so as to extend to the vicinity of the bottom of the container 21, and the bottom of the container 21 is formed in a conical shape 23. An electrode 25 having a gold electrode 24 at the tip is disposed in a direction toward the bottom formed on the electrode 23. Then, a certain amount of glass beads 26 are spread on the bottom of the conical shape 23. In addition, an overflow outlet 27 is provided in the upper direction of the container 21 to discharge the test water.
[0006]
In the electrode having such a structure, when the test water 16 supplied by the narrow tube 22 hits the bottom surface of the bottom of the conical shape 23, the electrode is reversed. At this time, the glass beads 26 are rolled up and the dirt is removed by hitting the gold electrode 24 at the tip of the electrode 25.
[0007]
As shown in FIG. 4, the structure for cleaning the electrode of the third specific example is such that an electrode 32 is arranged at the bottom of the container 31 for inputting the test water 16, and the lateral direction with respect to the electrode 32 in the faced state. In this structure, a water sample inlet 33 for inputting water is provided, and glass beads 34 are laid on the upper portion of the electrode 32 facing the bottom.
[0008]
Thus, when the test water 16 is supplied from the test water inlet portion 33 provided in the lateral direction of the bottom surface so that the glass beads 34 are always in contact with the electrode 32, the glass beads 34 are rolled up while being in contact with the electrode 32, When the glass beads 34 collide with the electrode 32 in the vortex of the test water 16, the tip portion of the electrode 32 is washed.
[0009]
As shown in FIG. 5, the structure for cleaning the electrode of the fourth specific example is provided at the bottom 37 of the water sample inlet 36 for inputting the water 16 to the bottom 37 of the water sample container 35. An electrode 38 is disposed at a position a predetermined distance above the test water inlet 36, a mesh 39 is disposed at the water test inlet 36 of the bottom 37, and a predetermined amount of glass beads 40 are spread on the bottom 37. It has a structure.
[0010]
In this way, the glass beads 40 are brought into contact with the electrode 38 at an upper position at a predetermined distance from the bottom 37 of the water sampling inlet 36. That is, when the test water 16 is supplied from the bottom 37, the glass beads 40 are blown up like a fountain, and the electrodes 38 are washed by colliding with the opposing electrodes 38.
[0011]
[Problems to be solved by the invention]
However, in the method for cleaning various electrodes described in the prior art, there is a problem that only the fine glass beads (washing beads) can be stirred because the flow rate of the test water is small.
[0012]
In addition, when the flow rate and flow rate fluctuate, the movement of the glass beads changes, resulting in a problem that the cleaning effect is not constant and the cleaning power is weakened.
[0013]
Furthermore, in the case of a rotating electrode that rotates the electrode in a glass bead, the test water can be expected to have a cleaning effect even in dirty water such as river water, but a signal can be output from the rotating electrode with a small contact resistance. There is also a problem that the function of taking out is required and the structure and structure become complicated.
[0014]
Therefore, in the electrode cleaning structure using glass beads, there is a problem that must be solved by a structure and structure that brings about a cleaning effect by making the structure less susceptible to the flow and flow rate of test water.
[0015]
[Means for Solving the Problems]
In order to solve the above problems, an electrode cleaning method and a residual chlorine meter according to the present invention are configured as follows.
[0016]
(1) In a bottomed cylindrical body that has a working electrode, a counter electrode, and a comparison electrode and accommodates test water, the shape of the bottom side wall surface and the counter electrode is made uneven in the vertical direction and a gap of a predetermined interval is maintained. The tip of the working electrode is disposed in a gap formed by the side wall surface and the counter electrode, and cleaning beads are flowed along with water from the lower lateral direction to the upper lateral direction of the gap. The working electrode is washed, and the comparative electrode is not washed with the beads.
(2) The electrode cleaning method according to (1), wherein the shape of the side wall surface of the bottomed cylindrical body and the shape of the electrode are formed in the same semicircular shape and circular shape.
[0017]
(3) Washing the working electrode and the counter electrode with a bottomed cylinder in which the test water is accommodated, a working electrode, a counter electrode and a comparison electrode installed in the bottomed cylinder, and cleaning beads flowing according to the flow of the water sample A residual chlorine meter equipped with electrode cleaning means,
The counter electrode installation portion in which the side wall surface on the bottom side of the bottomed cylindrical body is formed in a concave curved shape in the vertical direction; and the working electrode having a tip disposed in a gap formed by the side wall surface and the counter electrode;
Convex-curved counter electrode arranged so as to form a gap at a predetermined interval with the concave-curved side wall surface and obtain a predetermined creepage distance;
A water sample introduction pipe in which a water sample discharge port is arranged so that water flows from the lower side gap between the concave curved side wall surface and the counter electrode toward the upper side gap,
A plurality of cleaning beads formed of a member having a size that can pass through a gap between the concave curved side wall surface and the counter electrode and having a specific gravity heavier than test water, the counter electrode and the test water discharge port, And a space for storing the washing beads at the bottom.
(4) The concave side wall surface has a semicircular shape, and the second electrode is formed in a circular shape having the same shape as the semicircular side wall surface. Residual chlorine meter.
[0018]
In this way, the shape of the electrode and the shape of the side wall surface are made the same shape to maintain a gap of a predetermined interval and increase the creepage distance, and the cleaning beads are poured into the gap together with the test water from the lower direction. By performing the cleaning, it is possible to increase the distance that the cleaning beads for cleaning the electrode come into contact with each other. Therefore, it is possible to perform efficient cleaning even with a relatively simple structure.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of an electrode cleaning method and a residual chlorine meter according to the present invention will be described with reference to the drawings.
[0020]
The residual chlorine meter of the present invention has a structure based on a general polarographic method as a method for measuring the residual chlorine, in which an applied voltage is applied to the working electrode and the reference electrode, and a current flowing between the working electrode and the counter electrode remains. It is measured by being proportional to the concentration of chlorine.
[0021]
The current i by the polarographic method can be obtained by the following equation (1).
[0022]
i = nFDA × (C / δ) (1)
n: valence of reactant F: Faraday constant D: diffusion coefficient of reactant A: area of working electrode C: concentration of reactant δ: thickness of diffusion layer
As can be seen from this equation (1), the flowing current i is also proportional to the area of the working electrode, and therefore is affected by dirt and the like. For this reason, it is necessary to always clean the electrode surface of the working electrode so as not to get dirty and to keep it from getting dirty. Therefore, in the present invention, the glass beads (washing beads) are in contact with the exposed surface of the working electrode for a long time, and the thickness of the diffusion layer is kept constant, and the glass beads are washed. It is also characterized by a structure that can also be used.
[0024]
As shown in FIG. 1, a residual chlorine meter that can embody the electrode cleaning method of the present invention includes a bottomed cylinder 51 in which water is stored, and a side wall surface on the bottom side of the bottomed cylinder 51. An electrode installation portion 53 formed in a concave curved surface shape in the vertical direction, a working electrode 54 as a first electrode provided at a predetermined position of the concave curved side wall surface 52, and a concave curved side wall surface 52; A counter electrode 56 that is a convex-curved second electrode arranged so as to form a gap of a predetermined interval and gain a predetermined creepage distance, and a gap on the lower side between the concave-curved side wall surface 52 and the counter electrode 56 The test water introduction pipe 58 in which the test water discharge port 57 is arranged so that the test water flows from 55 to the upper gap 55 and the gap 55 between the concave curved side wall surface 52 and the counter electrode 56 can pass through. A plurality of washing members formed of members having a specific gravity greater than that of the test water. From the bead 59, the space 60 between the counter electrode 56 and the test water discharge port 57 where the cleaning bead 59 can be stored at the bottom, the comparison electrode 61, the overflow outlet 62 for discharging the test water, and the measurement unit 63 Become.
[0025]
The concave side wall surface 52 has a semicircular shape, and the counter electrode 56 has a structure formed in a circular shape having the same shape as the semicircular side wall surface 52.
[0026]
In the residual chlorine meter having such a structure, when the test water is poured into the test water introduction pipe 58, the test water flows from the test water discharge port 57, and the cleaning beads 59 stored in the space 60 at the bottom are rolled up, The cleaning beads 59 that flow into the gap 55 in the direction and flow in the direction of the upper gap 55 while hitting the surface of the counter electrode 56 and the working electrode 54 and jump out of the upper gap 55 descend to the space 60 due to their own weight. Then, if the test water is flowing, a swiveling motion is made such that the water enters the lower lateral gap 55 again and exits from the upper gap 55.
[0027]
Therefore, the surface on the working electrode 54 side of the counter electrode 56 is cleaned by the cleaning beads 59 that pass through the gap 55. In addition, the size of the gap 55 through which the cleaning beads 59 pass is limited, and the creeping distance to the counter electrode 56 is increased, that is, the circular gap 55 makes the distance in contact with the electrode surface larger. Therefore, it can wash | clean efficiently.
[0028]
【The invention's effect】
As described above, the electrode cleaning method and the residual chlorine meter according to the present invention have the same unevenness in the vertical direction between the electrode and the side wall surface of the bottomed cylindrical body containing the test water, specifically, the center position is the same. Since the electrodes are washed by pouring wash beads with test water into the gap between the circular shape and semicircular shape, the washing area can be increased and the time for washing can be increased. There is an effect that the cleaning efficiency of the electrode can be improved without increasing the flow velocity.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an electrode structure of a residual chlorine meter according to the present invention.
FIG. 2 is a cross-sectional view of the structure of an electrode of a residual chlorine meter of a first specific example in the prior art.
FIG. 3 is a cross-sectional view of a structure of an electrode of a residual chlorine meter of a second specific example in the prior art.
FIG. 4 is a cross-sectional view of the electrode structure of a residual chlorine meter according to a third specific example in the prior art.
FIG. 5 is a cross-sectional view of the electrode structure of a residual chlorine meter according to a fourth specific example in the prior art.
[Explanation of symbols]
51 Bottomed cylinder 52 Side wall surface 53 Electrode installation portion 54 Working electrode (first electrode)
55 Clearance 56 Counter electrode (second electrode)
57 Test water outlet 58 Test water introduction pipe 59 Washing beads 60 Space 61 Reference electrode 62 Overflow outlet 63 Measuring section

Claims (4)

In a bottomed cylindrical body that includes a working electrode, a counter electrode, and a comparison electrode and accommodates water, the shape of the bottom side wall surface and the counter electrode is uneven in the vertical direction and the creepage is maintained while maintaining a gap of a predetermined interval. The distance between the counter electrode and the working electrode is increased by arranging the tip of the working electrode in the gap formed by the side wall surface and the counter electrode, and flowing cleaning beads together with the test water from the lower lateral direction to the upper lateral direction of the gap. The electrode cleaning method is characterized in that the reference electrode is not cleaned with the beads.   2. The electrode cleaning method according to claim 1, wherein the shape of the side wall surface of the bottomed cylindrical body and the shape of the counter electrode are the same semicircular shape and circular shape. Electrode cleaning means for cleaning the working electrode and the counter electrode with a bottomed cylinder in which the test water is accommodated, a working electrode, a counter electrode and a comparison electrode installed in the bottomed cylinder, and cleaning beads flowing according to the flow of the test water A residual chlorine meter with
The counter electrode installation portion in which the side wall surface on the bottom side of the bottomed cylindrical body is formed in a concave curved shape in the vertical direction; and the working electrode having a tip disposed in a gap formed by the side wall surface and the counter electrode;
Convex-curved counter electrode arranged so as to form a gap at a predetermined interval with the concave-curved side wall surface and obtain a predetermined creepage distance;
A water sample introduction pipe in which a water sample discharge port is arranged so that water flows from the lower side gap between the concave curved side wall surface and the counter electrode toward the upper side gap,
A plurality of cleaning beads formed of a member having a size that can pass through a gap between the concave curved side wall surface and the counter electrode and having a specific gravity heavier than test water, the counter electrode and the test water discharge port, And a space for storing the washing beads at the bottom.   The residual chlorine meter according to claim 3, wherein the concave side wall surface is semicircular, and the second electrode is formed in a circular shape having the same shape as the semicircular side wall surface. .

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