JPH048367Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a concentration measuring device for measuring the concentration of sludge, etc.

Among suspension liquids, for example, in the case of sludge generated in a sewage treatment process, the liquid contains fine bubbles and gas bubbles. If such bubbles are included, when measuring the suspended concentration using ultrasonic waves, they will be reflected and scattered significantly at the gas-liquid interface, resulting in an error on the higher concentration side than the actual concentration, resulting in a large amount of bubbles. In some cases, it may become impossible to measure.

On the other hand, in a light beam type radiation type densitometer, since the air becomes more easily transmitted by the bubbles, the apparent density becomes thinner, resulting in an error in the lower concentration than the actual concentration.

Therefore, conventionally, when measuring the concentration of this type of suspension, a pressurized measurement chamber is provided that is separated from the sludge pipe by an on-off valve, and this chamber is closed off with the on-off valve. After the liquid was pressurized to a certain value to defoam, the concentration of the suspension was measured. In other words, by pressurizing the suspension liquid, the saturated solubility of the gas is increased, and the air bubbles contained in the liquid are dissolved, thereby eliminating the influence of the air bubbles.

Conventionally, pressurized air has been used as the pressurizing means, as shown in, for example, Japanese Utility Model Application Laid-Open No. 57-86453. However, in order to use pressurized air, the air compressor must be operated in advance to maintain the required air pressure. In addition, piping is required to send air pressure from the air compressor, and this piping system requires auxiliary equipment such as a pressure reducing valve and a filter, which is troublesome to manage. Moreover, there were other problems, such as the need for manpower to maintain the piping system and auxiliary equipment, and the condensed water generated as a result of air compression having to be discharged about once a day.

This idea was made in order to solve the above problem, and a sealed measurement chamber was installed in a part of the main sludge pipe via an on-off valve, and a movable A rod is provided on the pressure membrane through reinforcing plates attached to both sides thereof, and a cam of a mechanical pressing mechanism acts on the rod to move the pressure membrane and pressurize the sludge trapped in the sealed measurement chamber. It is an object of the present invention to provide a concentration measuring device which can eliminate air bubbles and accurately measure the concentration by pressurizing the sludge.

An embodiment of this invention will be described below with reference to the drawings.

A main sludge pipe 1 through which sludge flows is provided with a sealed measurement chamber 3 that is partially branched and opposed to a raised portion 2 on the inner surface.

The hermetically sealed measurement chamber 3 has an annular elastic spacer 5 made of an elastic body provided at the opening 4 at one end.
and an outer box 6 detachably fixed to the other end by bolting or the like, and a sludge concentration detector 7 is provided in the annular body between the outer box 6 and the elastic spacer 5. There is. This sludge concentration detector 7 consists of a pair of ultrasonic transmitter and receiver that face each other, and the measurement reception signal is transmitted to a recording device (not shown) or the like and processed.

On the other hand, on the inside of the elastic spacer 5 in contact with the opening 4, an on-off valve 9 is provided which is rotatably supported by a shaft 8 aligned with the opening surface. This on-off valve 9 is inscribed within the elastic spacer 5 as shown by the solid line, and can be rotated to a vertical position as shown by the imaginary line. Through this operation, the sludge flowing through the sludge main pipe 1 is sampled and the measurement chamber 3 is sealed. A room.

A movable pressure membrane 10 such as a rubber membrane is provided inside the sealed measurement chamber 3 and is fastened together with the sludge concentration detector 7.
A reinforcing plate 10 is attached to both sides of the pressure membrane in the eastern part of the
A rod 10a is attached to transmit the driving force of the pressurizing means 11 via the rods b and 10c. Also,
Although not shown in the figure, the pressure membrane 10 has a reinforcing wire inserted in the mesh, and a reinforcing plate 10 is placed in the center of the reinforcing wire.
b and 10c.

The pressurizing means 11 is constituted by a mechanical mechanism that does not use compressed air or the like at all, and in this embodiment, a cam 12 that slides the rod 10a in the vertical direction is used.
and a motor 13 for rotating this cam 12, and this motor 13, together with the on-off valve 9 and the concentration detector 7, is controlled by a control device (not shown).

Then, after keeping the inside of the sealed measurement chamber 3 at a constant pressure for a predetermined period of time, concentration measurement is performed. It is preferable that the pressurization time is performed using an adjustable timer and can be changed as appropriate depending on the sludge to be measured.

Next, the pressurized defoaming of the sludge in the sealed measurement chamber 3 and the replacement operation of the sampling sludge will be described.

In the figure, when the cam 12 engaged with the rod 10a is rotated with the on-off valve 9 in the open state as shown by the phantom line, the pressure membrane 10 moves from the stop position shown by the solid line to the pressurizing position shown by the phantom line. By moving up and down and repeating this operation one to several times, the sludge in the measurement chamber 3 can be completely replaced.

After the replacement of the sludge to be measured is completed in this way, the on-off valve 9 is placed in the closed position as shown by the solid line.
When the cam 12 is rotated again and the pressure membrane 10 is displaced to the pressure position shown by the imaginary line, the measurement chamber 3 is sealed, so the pressure is increased to a predetermined pressure value by compressive deformation of the pressure membrane 10. The air bubbles in the sludge dissolve and disappear, and the concentration is measured in this state. After measurement,
The cam 12 is rotated again to return the on-off valve 9 to the open state, and the measurement process is completed.

Therefore, in this invention, the above-mentioned pressurized defoaming of sludge,
Since the switching operation can be performed by a mechanical mechanism that does not use compressed air at all, there is no need for complicated adjustments that would be required when using compressed air, etc. Furthermore, there is no need for a compressor, etc., so the structure is extremely simple. That's enough.

In addition, when the above-mentioned on-off valve 9 is especially an electric valve,
Since the pressurizing means 11 and the like can all be integrated into an electrical structure, the structure becomes simpler.

As described above, according to this invention, a sealed measuring chamber is provided in a part of the main sludge pipe via an on-off valve, and a movable pressure membrane provided in a part of the sealed measuring chamber is attached to both sides of the sealed measuring chamber. A rod is installed through a reinforcing plate,
A cam of a mechanical pressing mechanism that acts on the rod to move the pressure membrane and pressurize the sludge trapped in the sealed measurement chamber is configured to pressurize the sludge. This eliminates air bubbles and allows accurate concentration measurements.

Further, since reinforcing plates are attached to the pressure membrane so as to face part of both sides thereof, uneven pressure is not concentrated on one point and is not applied. Moreover, since the pressure membrane is configured to indirectly transmit the pressing force by applying a cam of a mechanical pressing mechanism that acts on the rod, the transmission of mechanical pressing force exceeding the maximum movement point of the cam is impossible. It can't happen. Therefore, it functions as an overload protection device, and can reliably prevent fatigue and destruction of the pressurizing membrane due to overload and uneven pressing force, which solves the problem of using a mechanical pressing mechanism as a pressurizing means. It was possible to resolve this issue.

[Brief explanation of the drawing]

The figure shows a longitudinal sectional view of one embodiment of this invention. 1... Sludge main pipe, 3... Sealed measurement chamber, 7... Sludge concentration detector, 9... Open/close valve, 10... Pressure membrane,
11...pressurizing means.

Claims (1)

[Scope of utility model registration request] A sealed measurement chamber branched from the sludge main pipe, an on-off valve provided between the sealed measurement chamber and the sludge main pipe, a sludge concentration detector provided in a part of the sealed measurement chamber, and the sealed measurement room. A movable pressure membrane is installed in a part of the chamber, and a rod is provided through reinforcing plates attached to both sides of the pressure membrane, and the pressure membrane is moved to remove the sludge trapped in the sealed measurement chamber. and a cam of a mechanical pressing mechanism that acts on the rod so as to pressurize the rod.