JPH1194607A - Rotameter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotameter capable of preventing, when used in a water processing facility, etc., the adhesion of microorganisms such as algae to the inner surface of a taper pipe and their propagation and of preventing the adhesion of organic materials to the outer surface of the taper pipe, while requiring almost no maintenance and control. SOLUTION: The rotameter comprises a taper pipe 1 and a float 2 freely confined in the taper pipe 1. In this case, a thin film of a photocatalyst is supported on the inner surface or both the inner and outer surfaces of the taper pipe 1. The propagation of microorganisms such as algae is inhibited by a strong oxidizing force produced on the surface of the photocatalyst by light applied to the taper pipe 1 to prevent the adhesion of microorganisms such an algae to the inner surface of the taper pipe 1 and the adhesion of organic materials to the outer surface of the taper pipe 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor meter used for measuring a flow rate in many water treatment facilities, such as a water purification plant and a sewage treatment plant, wherein the rotor prevents adhesion and growth of microorganisms and attachment of organic substances. About the meter.

[0002]

2. Description of the Related Art Flow meters used in water treatment facilities such as water purification plants and sewage treatment plants include electromagnetic flow meters, ultrasonic flow meters, and rotameters. Rotameters are widely used in water treatment facilities and the like because of their characteristics of simplicity, accuracy, ease of maintenance, and low cost.

[0003] The rotameter measures the instantaneous flow rate by reading the position of the float freely accommodated in a taper tube made of a transparent material such as glass so that the inside can be seen, and reading the scale attached to the flow rate. You can know.

[0004] However, when the rotameter is installed in a place where light is irradiated, particularly outdoors, light passes through the inside of the tapered tube, so that microorganisms that perform photosynthesis, particularly algae, adhere to and grow on the inner surface of the tapered tube. Thus, not only is the float difficult to see, but also there is a major problem that accurate flow rate measurement becomes impossible. During the period when photosynthesis is active from spring to summer, this adherent growth of algae, etc., attaches to the entire inner surface of the tapered tube exposed to light in a short period of time, making the float invisible. Meters must be disassembled and cleaned frequently. For these reasons, there is great expectation for a rotameter to which algae do not adhere.

On the other hand, the fact that the photocatalyst has an algicidal action is described in Japanese Patent Application Laid-Open No. 7-275704. The bactericidal action of the photocatalyst is considered to be due to the strong oxidizing power of hydroxyl radicals generated by the reaction between water and holes in the valence band generated by photoexcitation. Proceedings of the Annual Meeting of the Society of Water Environment, 30th, Heisei 8
Year, p. 379, shows its bactericidal effect.

[0006] These bactericidal and algicidal effects are achieved by irradiating a photocatalyst such as titanium dioxide with light having a wavelength greater than the band gap (energy width between the valence band and the conduction band). Electrons jump out to the conduction band, electrons are generated in the conduction band, and holes are generated in the valence band. It utilizes the strong reducing power of electrons generated by the photoexcitation and the strong oxidizing power of holes.

Further, a technique for supporting a photocatalyst in the form of a thin film on a surface of glass or the like is also known (environmental management, V
ol. 32, P943-949, 1996).

[0008]

SUMMARY OF THE INVENTION The present invention relates to a rotameter used in water treatment facilities and the like, which prevents the growth of microorganisms such as algae on the inner surface of a tapered tube and prevents the growth of microorganisms such as algae on the outer surface of the tapered tube. It is an object of the present invention to provide a rotameter which can prevent the adhesion of a contaminant made of an organic substance and hardly requires maintenance.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a method in which a photocatalyst is carried on the inner surface or the inner and outer surfaces of a tapered tube of a rotameter, and the surface of the photocatalyst is irradiated with light irradiated on the tapered tube. Due to the strong oxidizing power
By suppressing the growth of microorganisms such as algae, it is possible to prevent the adhesion of microorganisms such as algae to the inner surface of the tapered tube, and to prevent the adhesion of contaminants made of organic substances to the outer surface of the tapered tube. Things.

[0010] The prevention of adhesion and growth of microorganisms on the tapered tube surface of the rotameter of the present invention is achieved by irradiating the rotor tube with
This is performed by using the transmitted light in reverse. That is, a photocatalyst activated by light irradiation is carried on the surface of the tapered tube in a thin film form, and the photocatalyst activated by the irradiation light prevents the growth of microorganisms such as algae by the bactericidal action. In addition, when light hits the photocatalyst carried on the outer surface of the tapered tube, the activated photocatalyst decomposes organic substances attached to the outer surface of the tapered tube and keeps the outer surface clean.

In the rotameter according to the present invention, the light containing ultraviolet rays such as sunlight hits the tapered tube carrying the thin-film photocatalyst, so that the photocatalyst carried on the surface of the tapered tube is activated and the photocatalyst is activated. Due to the strong oxidizing power generated on the surface, the growth of microorganisms such as algae on the inner surface of the tapered tube can be suppressed. Further, when the photocatalyst is also supported on the outer surface of the tapered tube, it is possible to prevent organic substances from adhering to the outer surface of the tapered tube.

Many photocatalysts are known, such as titanium dioxide, zinc oxide, tungsten trioxide, or those catalysts on which platinum, palladium, iron oxide, etc. are supported, and any of them can be used. Titanium dioxide is most preferable in consideration of cost, toxicity and the like.

The wavelength of light capable of photoexciting titanium dioxide is 3
It is 90 nm or less, and ultraviolet light included in sunlight can be used.

As described above, by supporting the photocatalyst in the form of a thin film on the surface of the tapered tube of the rotameter, the growth of microorganisms such as algae on the inner surface of the tapered tube and the adhesion of organic substances to the outer surface can be prevented. It is possible to measure the flow rate that can be prevented and hardly requires maintenance.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an example of an outline of a rotameter according to the present invention. In the drawing, 1 is a glass tapered tube carrying a photocatalyst on the inner and outer surfaces, 2 is a float, 3 is a float stopper for stopping the float 2 at the most falling point, 4
Prevents the liquid flowing in the float 2 from leaking out.
Ring 5 indicates fitting. 6 is a fluid,
The direction of the arrow indicates the flowing direction. Reference numeral 7 denotes light such as sunlight. If the rotameter of FIG. 1 is used in an environment where light is irradiated, the growth of microorganisms such as algae and the adhesion of organic matter can be prevented, and the position changes according to the flow rate of the fluid 6 flowing from the lower part to the upper part in the tapered tube 1. The scale corresponding to the position of the float 2 to be read can be accurately read.

The material of the tapered tube 1 is optimally quartz glass having good transmittance of ultraviolet light. However, the material is not limited as long as it transmits ultraviolet light. The photocatalyst in the present invention is titanium dioxide, and the supporting method is disclosed in
No. 939 and environmental management (Vol. 32, P943-9)
49, 1996).
The method of supporting the photocatalyst on the tapered tube 1 may be any method as long as the photocatalyst can be supported on the light-transmitting support, and the present invention is not limited to the methods described in the above-mentioned publications and documents.

When light 7 such as sunlight hits the photocatalyst carried on the surface of the tapered tube 1, the photocatalyst is activated and generates a strong oxidizing power. By this oxidizing power, it is possible to prevent microorganisms such as algae from adhering and growing on the inner surface of the tapered tube 1. In addition, the adhesion of the organic substance to the outer surface of the tapered tube 1 can be prevented,
The tapered tube 1 can keep the inner and outer surfaces clean.

[0018]

According to the rotameter of the present invention, microorganisms such as algae can be prevented from adhering and growing on the inner surface of the tapered tube and organic substances can be prevented from adhering to the outer surface of the tapered tube. Cleaning becomes unnecessary, and a flow rate measurement requiring almost no maintenance can be performed.

[Brief description of the drawings]

FIG. 1 shows an example of the outline of a rotameter according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Taper pipe 2 Float 3 Float stopper 4 O-ring 5 Fitting 6 Fluid 7 Light

Claims (1)

[Claims] 1. A rotameter comprising a tapered tube and a float freely accommodated therein, wherein a photocatalyst is carried on an inner surface or an inner and outer surface of the tapered tube.