JPS61168026A - Device for automatically preparing constant-concentration solution - Google Patents

Abstract

PURPOSE:To absorb the concentration variation of a newly prepared solution by means of an already prepared solution, by constituting the titled device in plural steps of a storage tank and stirring tank and utilizing a part of the volume of the stirring tank as a weighing mechanism, and then, supplying a solute and solvent to the specific volume at a constant speed. CONSTITUTION:A solute and solvent are supplied to a stirring tank 5 in set supplying rates in accordance with the detecting signal of the lower limit liquid level detector 4 of the stirring tank 5. The solute is supplied by means of a fixed quantity supplying device 1 and the solvent by opening a valve 2. The supply of the solute and solvent is stopped in accordance with the detecting signal of the upper limit liquid level detector 3 of the tank 5. Only when the detecting signal of the lower liquid level detector 10 of a storage tank 9 is inputted, a solution pump 7 is actuated and a solution is supplied to the storage tank 9 through a solution pipe 8. Since the quantity of the solution prepared in the stirring tank 5 is controlled by the upper limit and lower limit liquid level detectors 3 and 4 of the stirring tank 5, variation of the quantities of the solute and solvent is absorbed by the already existing solution in the storage tank 9 because the newly prepared solution is mixed with the already existing solution, even when quantities of the solute and solvent slightly fluctuate at the time of preparation.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an apparatus for automatically supplying a constant concentration solution.

It is an important issue to stably supply a solution with a constant concentration industrially.

(Prior art and its problems) In order to obtain a solution with a constant concentration, we have traditionally used a batch method or, in the case of a continuous method, by strictly quantitatively supplying the solvent and solute. In the case of the type, manual labor is required, and in the case of the continuous type, the apparatus is complicated and large, making it difficult to easily obtain a solution with a constant concentration.

(Means for solving the problem) In view of the above-mentioned circumstances, the present inventors have conducted various studies with the aim of obtaining a device that can automatically supply a constant concentration solution with a simple structure and stable operation. As a result, we have arrived at the present invention.

That is, the automatic preparation device for constant concentration solutions according to the present invention is as follows.

(7) A mechanism that continuously supplies solute to the stirring tank in a set amount per unit time.

(a) A mechanism for supplying the solvent to the stirring tank; and a storage tank connected to the gradient liquid feeding means and having a function of detecting the liquid level of the solution to be held at a specific liquid level as the lower limit. At least (a) by a signal detecting the lower limit of the liquid level in the storage tank.

A function that drives the liquid feeding means to send the solution that is filled to the upper limit of the stirring tank to the storage tank.

(b) A function that stops driving the liquid feeding means in response to a signal that detects the lower limit of the liquid level in the stirring tank; and (c) A function that uses the signal that detects the lower limit of the liquid level in the stirring tank as described in (7) and (a) above. and (d) a function to stop the function (a) in response to a signal that detects the upper limit of the liquid level in the stirring tank.

This is an automatic constant concentration solution preparation device characterized by comprising:

A solution in the present invention does not necessarily include a true solution, but also includes an emulsion or suspension having a substantially uniform composition, and the solute may be a solid, a solid, or a suspension as long as it can be supplied stationary. Both liquids and gases are applicable to the present invention.

The device for obtaining a constant concentration of the present invention does not have a single configuration, but has a double membrane configuration consisting of a storage tank and a stirring tank, and uses a part of the volume of the stirring tank as a measuring mechanism, so that the solute is ,
By supplying a solvent, a constant concentration of the solution is achieved. In other words, a part of the stirring tank is used as a measuring basin, and the volume of this basin is determined by a mechanism for detecting the upper and lower limits of the liquid level in the stirring tank.

The present invention will be explained in more detail using the drawings.

When the liquid level in the stirring tank 5 falls to the detection position of the lower limit liquid level detector 4, the solute is released in a preset amount per unit time.
The solute is supplied to the stirring tank 5 by the solute quantitative supply device 1 .

As the name suggests, the stirring tank 5 is equipped with a stirrer 6.

The solute quantitative supply device 1 is 1. For example, if it is a liquid, it is a differential pressure type 1
These include area type, electromagnetic type, and volumetric type flowmeters.

Any mechanism that continuously stops the supply of a predetermined amount may be used.
Similarly, any mechanism that can supply a constant amount of gas or solid may be used.

The solvent supply mechanism 1 may be a pipe equipped with an on-off valve 2, for example, and the on-off valve 2, such as a solenoid valve, is opened by a detection signal from the lower limit liquid level detector 4 of the stirring tank 5, and the upper limit liquid level detector is opened. Although the mechanism that closes when the detection signal No. 3 is detected is simple and convenient, it is not necessarily limited to this. Started by.

It suffices if it is stopped by the upper limit liquid level detector 3.

The liquid level in the stirring tank 5 can be detected using a known differential pressure type, isolation type,
Any type of liquid level detector such as a displacement type, air purge type, electrode type, or float type may be used, but the electrode type liquid level detector is industrially inexpensive and simple. Further, the liquid level detector of the storage tank 9 is also similar to this.

The setting position of the lower limit liquid level detector 4 is preferably set above the level of the stirrer 60 blades with some margin. This is because the liquid level drops below around 60 blades of the stirrer and various troubles occur.

The constant concentration solution prepared in the stirring tank 5 is as follows.

The liquid is intermittently sent to the storage tank 9 by the liquid sending pump 7.

The liquid feeding pump 7 is stopped and started when the lower limit liquid level detector 4 detects a signal indicating that the liquid level in the stirring tank has reached the upper limit and the liquid level in the storage tank 9 has reached the lower limit. Then, it is stopped by a detection signal of the lower limit of the liquid level in the stirring tank.

In the constant concentration blending device of the present invention, the amount of liquid blended in the stirring tank is regulated by the liquid level detectors at the upper and lower limits of the stirring tank, so the solute and solvent cap may vary slightly during blending. too(
Even if the concentration varies slightly from the target value), the variation is absorbed by the solution as a whole because it is mixed with the already prepared liquid in the storage tank.

How to set the lower limit of the storage tank, or in other words, how large or small the amount of remaining liquid is, depends on the size of the equipment used and the target accuracy of the concentration.

If the concentration needs to be changed, this can be easily done by changing the set value of the solute supply amount or the upper or lower limit liquid level detector settings of the stirring tank.

(for production) The present invention will be specifically explained below based on the drawings.

The drawings illustrate a schematic diagram of the device of the present invention,
In the figure, the solute is supplied in quantitative supply device 1.

The solvents are each supplied to the stirring tanks 5 via the on-off valves 2 for solvent supply. The stirring tank 5 is provided with a stirrer 6, an upper limit liquid level detector 3 as a liquid level upper limit detection mechanism, and a lower limit liquid level detector 4 as a lower limit detection mechanism.

The liquid is sent to the storage tank 9 via the pump 7&C-''C liquid sending pipe 8.

The storage tank 9 is provided with a liquid level detector 10 as a mechanism for detecting the lower limit of the liquid level, and the obtained constant concentration solution is delivered via a liquid sending pipe 11.

The solute and the solvent are supplied to the stirring tank by a detection signal from the lower limit liquid level detector 4 of the stirring tank 5, and the solute is supplied to the stirring tank by the metering supply device 1, and the solvent is also supplied to the stirring tank by opening the valve 2 according to the signal. When the liquid level in the stirring tank 5 reaches the upper limit according to a detection signal from the liquid level upper limit detector 3 of the stirring tank 5, the valve 2 is closed based on the signal, and the solute quantitative supply device 1 is stopped.

As a result, predetermined amounts of solute and solvent are supplied to the stirring tank 5.

Further, the stirrer 6 may be used to stir the solution as appropriate depending on the properties and properties of the solution. A stirrer may also be provided in the storage tank 9.

Next, regarding the liquid transfer to the storage tank 9, the liquid transfer pump 7 is operated only when a detection signal from the liquid level lower limit detector 10 of the storage tank 9 is received, and the liquid is sent to the storage tank 9 through the liquid transfer pipe 8. However, it will not start unless the upper limit liquid level in the stirring tank is detected. In other words, if the signal is input while the solute and solvent are being introduced into the stirring tank 5 during liquid transfer, problems will occur in the concentration and solute dissolution. The liquid feeding pump 7 will not operate unless the liquid enters the liquid. Therefore, even if the signal from the liquid level detector 10 of the storage tank 9 is detected, the liquid feeding pump 7 will not be activated unless the upper limit liquid level of the stirring tank is detected. From this point of view, the stirring tank must have sufficient capacity to meet the consumption of the constant concentration liquid. Also, the capacity of the storage tank must be equal to or greater than the volume of the constant concentration solution made at one time in the stirring tank.

1. In the present invention, if a certain amount of time is required to dissolve the solute, the liquid feeding to the storage tank is not started immediately even when the signal from the liquid level upper limit detector 3 of the stirring tank 5 is detected (for example, the timer function Wait until the solute is completely dissolved before pumping the solution.

As the liquid feeding means, instead of the pump 70, the stirring tank 5 may be placed in a pot comb rather than the storage tank 9, or the liquid feeding pipe 8 may be provided with an on-off valve, or a head may be used to send the liquid to the storage tank. Further, it is preferable to provide a backflow valve at the outlet of the pump 7 in order to prevent backflow of liquid when the pump 7 is stopped.

The constant concentration solution in the storage tank passes through the liquid transfer pipe 11 as needed and is sent to the user side using a liquid transfer means such as a pump.

In this way, the present invention allows a solution of a constant concentration to be easily obtained automatically by repeating the above-mentioned operations.

(Effects of the Invention) Since the present invention has such a simple structure and configuration and is automated, once the supply amount of solute Completely solve the complex problem.

Continuously and extremely stable without any human intervention? A solution of a[ can be obtained.

(Example) Hereinafter, the present invention will be specifically explained with reference to Examples regarding the preparation of a constant concentration solution of a polymer flocculant.

Example 1 A stirring tank with an effective capacity of 7 and a stirrer as shown in the figure (upper limit detection 6
．． Od lower limit detection 1.5d) and effective capacity 12- storage tank (
A solution of 0.10% cylindrical flocculant was continuously prepared using a liquid level detection device 7-). still.

The consumption amount of constant concentration solution is 5001! ~2000I! /h, and the polymer flocculant is supplied to the stirring tank once for 10h, /
h was supplied using a table feeder, tap water was used as the solvent, and water was supplied by opening and closing a solenoid valve.

Tap water pressure was 2-5 to 9/ci.

When the concentration (storage tank) of the obtained solution was measured over time, very good results were obtained as shown in Table 1.

Regarding the concentration measurement, a tracer was added and the concentration of the flocculant was calculated from the concentration of the tracer.

Table 1

[Brief explanation of the drawing]

The drawing is a schematic diagram showing an example of the device of the present invention. In the figure, 1 is a solute quantitative supply device, 2 is an on-off valve for solvent supply, 3 is an upper limit liquid level detector, 4 is a lower limit liquid level detector, 5 is a stirring tank, 6 is a stirrer, 7 is a liquid sending pump, 8 is a liquid feeding pipe, 9
is a storage tank, and 10 is a liquid level detector. Reference numeral 11 indicates a liquid feeding pipe on the use side.

Claims (1)

[Claims] (a) A mechanism for continuously supplying the solute to the stirring tank in a set amount per unit time; (b) A mechanism for supplying the solvent to the stirring tank; (c) A mechanism for supplying the solvent to the stirring tank in advance; It is equipped with a function of detecting the set upper and lower limits and a function of stirring the content liquid, and is connected to a stirring tank connected to the storage tank via a liquid feeding means, and (d) connected to the liquid feeding means. , in a solution blending device equipped with a storage tank that has a function of detecting a specific liquid level as the lower limit of the liquid level of the solution to be held, at least (a) a signal is sent by detecting the lower limit of the liquid level of the storage tank; (b) A function to drive the liquid means to send the solution filled to the upper limit of the stirring tank to the storage tank; (b) a function to stop driving the liquid sending means in response to a signal that detects the lower limit of the liquid level in the stirring tank; (c) A function that activates the functions of (a) and (b) above in response to a signal that detects the lower limit of the liquid level in the stirring tank, and (d) A function that activates the functions (a) and (b) above in response to a signal that detects the upper limit of the liquid level in the stirring tank. An automatic constant concentration solution blending device characterized by having a function of stopping the function of.