JPS6118411Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an apparatus for stabilizing the liquid level when measuring the liquid level of thickened sludge or the like.

Conventionally, the liquid level of thickened sludge in a storage tank has generally been measured using an ultrasonic water level gauge or an electrode rod. However, the liquid level of the thickened sludge tends to generate bubbles mechanically or over time, forming a bubble layer, and furthermore, scum and the like float to form a solid layer on the upper surface. If these bubble layers or solid matter layers are present, measurement using an ultrasonic water level meter may result in inaccurate measurement values due to absorption or diffuse reflection of ultrasonic waves, and in some cases, measurement may become impossible. Furthermore, when electrode rods are used, foreign matter often adheres to the electrode rods, resulting in erroneous measurements.

In order to deal with these problems, the inventors of the present invention surrounded the liquid level in the measuring section with a bottomless tube, used a baffle plate to prevent air bubbles and floating objects from entering, and also introduced pressurized air. Various attempts were made, including spraying to disperse foreign matter on the surface, but none of them yielded satisfactory results.

The present invention was developed based on the above-mentioned circumstances, and its purpose is to constantly stabilize the liquid level in the measuring section without being affected by bubbles or floating objects. In addition, by maintaining the liquid level in a stable state, the liquid level can be measured, and the volume, flow rate, etc. of the liquid can be easily and accurately managed.

The outline of the present invention is to always supply clean liquid to the liquid level of the measurement part and to match the liquid level with the liquid level of the tank.

The present invention will be explained below with reference to a specific example shown in the drawings. In Fig. 1, 1 is the liquid level of the liquid in the storage tank, for example, thickened sludge, and this sludge liquid has a measuring tube 2,
A stabilizing device is provided that includes an injection pipe 3 and a liquid level control pipe 4, as well as a communication pipe 5 that communicates their lower ends. The opening of the measuring tube 2 always protrudes above the liquid level 1, and a liquid level detector 6 such as an ultrasonic water level gauge is disposed preferably above the center line of the measuring tube 2 or above where it can be measured. and measurement cylinder 2
It is now possible to measure the liquid level inside. The injection port 3a of the injection pipe 3 is located above the liquid level 1, from which the cleaning liquid 7 is poured.

The liquid level control tube 4 consists of a flexible tube with an enlarged diameter portion 4a at the upper part, and floats 8, 8 are attached to the neck so that the upper opening always protrudes above the liquid level 1.
is provided. Further, a cleaning liquid outlet 4b is formed in the lower part of the liquid level control tube 4 close to the liquid level 1. Furthermore, a porous guide tube 9 is disposed around the liquid level control tube 4, and serves as a guide for raising and lowering the liquid level control tube 4.

When measuring the liquid level, the cleaning liquid 7 is poured, and the cleaning liquid 7 is supplied to the measuring tube 2 and the liquid level control tube 4 through the communication pipe 5. And always a small amount of cleaning solution 7
continues to be injected, and when the liquid level matches the liquid level in the tank, the excess cleaning liquid is discharged from the outlet 4b, and the liquid level of the cleaning liquid 7 and the liquid level 1 in the tank are always made to match. In this state, the liquid level detector 6 detects the measurement tube 2.
The liquid level of the cleaning liquid 7 in the tank is measured and set as the liquid level 1 of the tank.

In this way, the inside of the measuring tube 2 is filled with the cleaning liquid 7, and the liquid level matches the liquid level 1 of the tank, so it is not affected by air bubbles or floating objects caused by the liquid in the tank. Liquid level can be measured.

In the above example, a flexible liquid level control pipe was used and the discharge port was raised and lowered, but as shown in FIG. 'a' or, as shown in FIG. 3, a plurality of small holes may be formed at intervals in the vertical direction as a discharge port 4'b.

Further, when the liquid level 1 hardly changes, a liquid level control pipe 4'' may be used with the upper opening facing directly below the liquid level 1, as shown in FIG.

Here, it is desirable that the cleaning liquid 7 to be poured be a clean liquid that does not contain any impurities that would adversely affect the measurement, and that has the same specific gravity as the tank liquid. However, even if the specific gravity is slightly different, Since the error between them is small, it does not pose a big problem in practice. On the other hand, the injection speed of the cleaning liquid may be sufficient as long as it can prevent the liquid in the tank from flowing into the liquid level control pipe from the outlet when the liquid level 1 in the tank fluctuates (especially when it rises). , a small amount is sufficient. Furthermore, if the cleaning liquid in the stabilizer becomes contaminated due to splashes of liquid in the tank, by temporarily injecting a large amount of cleaning liquid, the contaminated liquid can be prevented from overflowing.

Note that the device of the present invention can be used not only for measuring the liquid level of thickened sludge, but also for general liquid level measurement where bubbles or floating objects are generated.

As described above, in the present invention, the measuring tube separated from the tank liquid is filled with cleaning liquid, and the level of the cleaning liquid is always the same as the liquid level in the tank, so that air bubbles and Accurate liquid level measurement is possible without being affected by floating objects.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing one embodiment of the device of the present invention, and FIGS. 2 to 4 are schematic cross-sectional views showing different embodiments of the liquid level control tube. 1...Liquid level in tank, 2...Measuring cylinder, 3...Injection pipe, 4, 4', 4''...Liquid level control pipe, 4b, 4'
a, 4'b...Discharge port, 6...Liquid level detector, 7...
...Cleaning liquid.

Claims (1)

[Scope of utility model registration request] A measurement cylinder that always protrudes above the liquid surface, a liquid level detector that detects the liquid level inside this measurement cylinder, an injection pipe that has an injection port above the liquid surface into which cleaning liquid is poured, and a cleaning liquid discharge port. and a liquid level control tube held below the liquid surface, the measuring tube, the injection tube and the lower part of the liquid level control tube are in communication with each other, and at least during measurement, a small amount of cleaning liquid is injected from the injection tube. A liquid level measuring and stabilizing device characterized in that a cleaning liquid corresponding to the amount of injection is discharged from the discharge port.