TWI759381B - Diluted solution producing device and diluted solution producing method - Google Patents

Abstract

A diluted solution producing device 10 according to this invention comprises a first pipe 11 for supplying first liquid, a first tank 12a for storing second liquid, a second pipe 13 for connecting the first tank 12a and the first pipe 11, a pressure adjustment section 18 for adjusting the pressure within the first tank 12a, the pressure adjustment section 18 pumping the second liquid within the first tank 12a through the second pipe 13 so as to supply the second liquid to the first pipe 11, a control section 20 that adjusts the added amount of the second liquid to the first liquid performed by the pressure adjustment section 18 based on measured values of the flow rate and concentration of the first liquid or the diluted solution flowing in the first pipe 11 so as to change the concentration of the diluted solution into a prescribed concentration, and a second tank 12b serially connected to the first tank 12a for temporarily storing the second liquid to be supplemented to the first tank 12a.

Description

Diluent production device and diluent production method

The present invention relates to a dilution liquid manufacturing apparatus and a dilution liquid manufacturing method.

Conventionally, in the manufacturing process of semiconductor devices and liquid crystal devices, ultrapure water from which impurities have been highly removed has been used as a cleaning solution for cleaning electronic components such as semiconductor wafers and glass substrates. It is known that in cleaning using such ultrapure water, since ultrapure water having a high resistivity value is used, static electricity is easily generated during cleaning, which may lead to electrostatic breakdown of the insulating film and reattachment of particles. Therefore, in recent years, in order to adjust the resistivity value (conductivity) to a predetermined range and suppress the generation of static electricity, a chemical solution such as ammonia water and carbonated water is added to ultrapure water with high precision and adjusted to a predetermined concentration. diluent.

As an apparatus for producing such a diluent, Patent Document 1 describes a production apparatus including a first pipe for supplying ultrapure water, a tank for storing the chemical solution, a second pipe for connecting the tank and the first pipe, adjustment A pressure regulator for the pressure in the tank; this manufacturing device produces a diluent by sending the chemical in the tank through the second pipe and adding it to the ultrapure water in the first pipe using the pressure regulator. According to this manufacturing apparatus, by appropriately controlling the pressure in the tank according to the measured value of the flow rate of the ultrapure water or the diluent and the concentration of the diluent, the addition amount of the chemical solution can be adjusted with high precision, and as a result, the production can be adjusted to a predetermined level. concentration of diluent. [Prior Art Literature] [Patent Literature]

[Patent Document 1] International Publication No. 2016/042933

[Problem to be Solved by the Invention] In the case of a production apparatus for a dilution liquid, when the produced dilution liquid is used for cleaning electronic components such as semiconductor wafers and glass substrates, it is required to continuously and stably produce a predetermined concentration adjusted The diluent is supplied to the end of use. However, in the manufacturing apparatus described in Patent Document 1, when the chemical solution in the tank is used up, the operation of the apparatus needs to be stopped, the pressure in the tank is released, and the chemical liquid needs to be replenished, or it needs to be replaced with another tank filled with the chemical liquid. In such a case, it takes time to stabilize the concentration of the produced diluent after restarting the operation of the apparatus. In addition, considering the viewpoint of the continuous operation of the apparatus, it is also considered to replenish the chemical liquid in the same tank while the chemical liquid is continuously supplied from the tank until the chemical liquid in the tank is used up. However, in such a replenishing method, the supply of the chemical solution from the tank is performed by controlling the inside of the tank to be in a pressurized state with a pressurizing gas. Therefore, the produced diluent will be disturbed due to the disturbance of the pressure control in the tank. The concentration becomes unstable.

Therefore, the objective of this invention is to provide the dilution liquid manufacturing apparatus and the dilution liquid manufacturing method which can continuously and stably manufacture the dilution liquid adjusted to predetermined density|concentration. [Means of Solving Problems]

In order to achieve the above-mentioned object, the dilution liquid manufacturing apparatus of the present invention produces a dilution liquid of the second liquid by adding the second liquid to the first liquid, and supplies the dilution liquid to the end of use; and has: a first piping, Supply the first liquid; the first tank stores the second liquid; the second piping connects the first tank with the first piping; the pressure adjustment part adjusts the pressure in the first tank, and adjusts the pressure in the first tank to the second liquid in the first tank. The liquid is pressure-fed through the second pipe and supplied to the first pipe; the control unit adjusts the first liquid or the diluent flow through the first pipe according to the measured value of the flow rate of the first liquid or the diluent and the concentration of the diluent. 2. The amount of liquid added to the first liquid so that the concentration of the diluent becomes a predetermined concentration. Further, the dilution liquid manufacturing apparatus of the present invention has, in one aspect, a second tank that is connected in series with the first tank and temporarily stores the second liquid to be replenished to the first tank, and has a second tank that is connected to the first tank in another aspect. The 1st tank is connected in parallel, and the 2nd tank which stores the 2nd liquid to be supplied to the 1st piping instead of the 1st tank.

In addition, the method for producing a diluent of the present invention is to produce a diluent of the second liquid by adding the second liquid to the first liquid, and supply the diluent to the end of use; and includes the steps of: supplying the first liquid To the first piping; supply the second liquid to the first piping, adjust the pressure in the first tank where the second liquid is stored, and pressurize the second liquid in the first tank by connecting the first tank and the first piping. Connect the second pipe and supply it to the first pipe, including measuring the flow rate and diluent concentration of the first liquid or diluent flowing through the first pipe, and adjusting the amount of the second liquid to the first liquid according to the measured value. Add the amount so that the concentration of the diluent becomes a predetermined concentration. Further, the method for producing a diluent of the present invention, in one aspect, includes the following steps: temporarily storing the second liquid in a second tank connected in series with the first tank; The second liquid of the second tank is replenished to the first tank. In another aspect comprising the steps of: storing the second liquid in a second tank connected in parallel with the first tank; supplying the second liquid from the second tank instead of the first tank according to the liquid level in the first tank to the first piping.

In such a dilution liquid manufacturing apparatus and dilution liquid manufacturing method, by using two tanks, before one tank is used up, the second liquid can be supplied from the other tank to the tank, or the second liquid can be switched to the other tank to supply the second liquid. liquid. Thereby, the operation of replacing the tank, etc., and the stoppage of the operation of the apparatus are not required, and the production of the diluted solution can be continued stably. [Effect of invention]

As described above, according to the present invention, a dilution liquid adjusted to a predetermined concentration can be produced continuously and stably.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(1st Embodiment) FIG. 1 is a schematic block diagram of the dilution liquid manufacturing apparatus which concerns on the 1st Embodiment of this invention. In addition, the configuration shown in the figure is only an example, and of course, it can be appropriately changed according to the purpose of use, application, and required performance of the device. For example, it is self-evident that a valve and a filter are added.

The dilution liquid manufacturing apparatus 10 includes: a first piping 11 for supplying the first liquid; two tanks 12a and 12b for storing the second liquid; The second piping 13 is provided. The second liquid is the medicinal liquid to be diluted, and the first liquid is a dilution medium for diluting the second liquid. Therefore, the dilution liquid manufacturing apparatus 10 produces the dilution liquid of the second liquid by adding the second liquid through the second piping 13 to the first liquid flowing through the first piping 11, and passes the obtained dilution liquid through the second piping 13. 1. The piping 11 is supplied to the use end 1.

The type of the first liquid is not particularly limited, and alcohols such as ultrapure water, pure water, water obtained by dissolving electrolytes and gases, and isopropyl alcohol can be used according to the application. In addition, as for the second liquid, as long as it is used for the purpose of dilution, its type is not particularly limited, and water obtained by dissolving electrolytes and gases, such as carbonated water, hydrogen-rich water, etc., can be used according to the application; isopropyl alcohol and other alcohols. When the produced diluent is used for cleaning of semiconductor wafers, it is preferable to use ultrapure water as the first liquid and an aqueous ammonia solution as the second liquid. Alternatively, a tetramethylammonium hydroxide (TMAH) aqueous solution may be appropriately used as the second liquid. In addition, the ultrapure water referred to here refers to treated water obtained by removing ions and non-ionic substances from the water to be treated (raw water) using an ultrapure water production apparatus, and specifically refers to a resistivity value of 18MΩ･ Treated water above cm.

The two grooves 12a and 12b are connected in parallel with each other. That is, the two grooves 12a, 12b are connected in series with the plurality of second pipes 13 via the valves 14a, 14b, respectively, on the outlet side thereof. Valves 13a are provided on the inlet sides of the plurality of second pipes 13, respectively. A filter F1 is provided between the two valves 14a, 14b and the plurality of valves 13a. In addition, instead of the two valves 14a and 14b, a three-way valve may be provided on the outlet side of the two grooves 12a and 12b. In addition, the two tanks 12a and 12b are connected to a chemical solution supply line (liquid supply means) 16 for supplying the second liquid to each of the tanks 12a and 12b via valves 15a and 15b, respectively. Filters F2 and F3 are provided between the valve 15a and the tank 12a and between the valve 15b and the tank 12b, respectively, and a valve 16a is provided in the chemical solution supply line 16 . Furthermore, atmospheric valves 17a and 17b are provided in the two grooves 12a and 12b, respectively. In addition, instead of the two valves 15a and 15b, a three-way valve may be provided on the inlet side of the two grooves 12a and 12b.

Further, the dilution liquid manufacturing apparatus 10 has a pressure adjusting unit 18 for adjusting the pressure in the tanks 12a and 12b as a means for feeding the second liquid in the tanks 12a and 12b through the second piping 13 and supplying it to the first piping 11 under pressure. means. The pressure adjustment unit 18 includes a tank pressurizing gas supply line 18a for supplying the tank pressurizing gas to the tanks 12a and 12b, and an intake and exhaust mechanism 18b provided in the tank pressurization gas supply line 18a. The intake and exhaust mechanism 18b is constituted by an intake valve 18c and an exhaust valve 18d, and by opening and closing these valves, the inside of the grooves 12a and 12b can be pressurized or depressurized. In addition, the intake and exhaust mechanism 18b is not limited to the configuration shown in the figure, that is, it is not limited to the configuration of the intake air pressurizing mechanism (intake valve 18c) and the exhaust gas decompression mechanism (exhaust valve 18d) individually, for example The intake air pressurizing mechanism such as an electric pneumatic regulator and the exhaust gas decompression mechanism may be integrated. The tank pressurizing gas supply line 18a is connected to one tank (first tank) 12a via a valve 19a, and is connected to the other tank (second tank) 12b via a valve 19b. Moreover, the pressure gauge 19c which measures the supply pressure of the gas for tank pressurization is installed in the gas supply line 18a for tank pressurization. The type of gas used for tank pressurization is not particularly limited, and nitrogen gas, which is a passive gas that can be used relatively easily, is preferably used. However, when the produced diluent is used for cleaning and cleaning of the object to be treated including materials that are easily oxidized, oxygen and air should be avoided as the gas used for tank pressurization. Therefore, even when a passive gas such as nitrogen is used, it may be affected by oxygen contained as an impurity, and its purity needs to be fully considered.

In the present embodiment, at the time of the normal operation of producing the dilution liquid, the second liquid is alternately supplied to the first piping 11 from the two tanks 12a and 12b. That is, the first supply mode of supplying the second liquid from the first tank 12a to the first piping 11 and the second supply mode of supplying the second liquid from the second tank 12b to the first piping 11 are based on the respective tanks 12a, The liquid level in 12b is properly switched. For example, in the first supply mode, when the liquid level in the first tank 12a falls below a predetermined lower limit liquid level, the supply of the second liquid from the first tank 12a is stopped and the second liquid is supplied from the second tank 12b. This switching operation will be described later.

In this embodiment, the supply of the second liquid system to the first piping 11 is performed through one of the plurality of second piping 13, but in order to achieve a wide range of supply of the second liquid, the inner diameter of the plurality of second piping 13 is and at least one of the lengths are different from each other. That is, the plurality of second pipes 13 are configured such that at least one of their inner diameter and length is different from each other so that the second liquid can be passed through at different flow rates even if the pressure in each of the grooves 12a and 12b is constant, for example. The structure of these 2nd piping 13 is also mentioned later.

Furthermore, the dilution liquid manufacturing apparatus 10 has the control part 20 which controls various operation|movements of the dilution liquid manufacturing apparatus 10. In particular, the control unit 20 can adjust the flow rate measurement means 21 for measuring the flow rate of the first liquid flowing through the first piping 11 and the concentration measurement means 22 for measuring the concentration of the diluent, based on at least the measurement results. 2. The amount of liquid added to the first liquid so that the concentration of the diluent becomes a predetermined concentration. Hereinafter, the method of adjusting the addition amount of the second liquid by the control unit 20 will be described, but before that, the Hagen-Poiseuille rule which is the basis for the adjustment of the addition amount will be briefly described .

Hagen-Bailey's Law is a law about the head loss of laminar flow in a circular pipe. If the inner diameter of the pipe is defined as D[m], the length of the pipe is L[m], and the pressure gradient at both ends of the pipe is ΔP[Pa], the viscosity coefficient of the liquid is μ[Pa･s], and the flow rate of the liquid flowing through the pipe is Q[m ³ /s], then it is expressed by the following relationship: Q＝(π×D ⁴ ×ΔP )/(128×μ×L). That is to say, according to Hagen-Bailey's Law, the flow rate Q of the liquid flowing through the circular tube is proportional to the 4th power of the inner diameter D of the circular tube and the pressure gradient ΔP at both ends, and is proportional to the length L of the circular tube and the liquid The viscosity coefficient μ is inversely proportional.

In the diluent manufacturing apparatus of the present embodiment, the Hagen-Bailey-Soil's law is applied to the supply of the second liquid through each of the second pipes. The length L and the inner diameter D of each second pipe are fixed values, and if the type of the second liquid is determined, the viscosity coefficient μ is also a fixed value. Therefore, only by controlling the pressure in the tank corresponding to the pressure gradient ΔP between the two ends of each second pipe, the flow rate Q in each second pipe can be proportionally controlled.

Next, when adding the second liquid to the first liquid from the first tank 12a, a method of adjusting the amount of the second liquid added by the control unit 20 will be described.

First, a target value of the concentration of the dilution liquid to be produced is set, and the addition amount of the second liquid is calculated with respect to the set target concentration. Specifically, the flow rate of the first liquid is measured by the flow rate measuring means 21, and the target addition amount of the second liquid to achieve the target concentration is calculated. Then, with respect to the calculated target addition amount, one of the second pipes 13 to be used is determined among the plurality of second pipes 13, and the first second pipe 13 to achieve the target addition amount (flow rate) is calculated for the determined second pipe 13. The target value of the pressure in the tank 12a. Then, after opening the valve 13a of the second piping 13 to be used, the pressure in the first tank 12a is adjusted to the calculated target pressure by the pressure adjusting unit 18, thereby removing the second liquid from the first The tank 12a is added to the first liquid in the first piping 11 through the second piping 13 .

At this time, the flow rate Q of the second liquid flowing through the second pipe 13 is proportional to the pressure gradient ΔP at both ends of the second pipe 13 according to the above-mentioned Hagen-Bailey's Law. Therefore, for example, when the flow rate of the first liquid changes, the pressure in the first groove 12a is changed so that the pressure gradient ΔP is proportional to the change by a constant proportionality. For example, when the flow rate of the first liquid is doubled, the pressure gradient ΔP is doubled, and the flow rate of the second liquid is also doubled, and when the flow rate of the first liquid is 1/2, the pressure gradient ΔP is made 1 /2, and the flow rate of the second liquid also becomes 1/2. By such an adjustment method, as a result, the proportional relationship between the flow rate of the first liquid and the flow rate of the second liquid can be maintained, and even when the flow rate of the first liquid fluctuates, a diluent with a stable concentration can be obtained.

However, due to volatilization, decomposition, etc. of the second liquid in the first tank 12a, the concentration of the second liquid itself may not be constant. At this time, even if it is initially adjusted within a predetermined concentration range including the target concentration, the concentration of the produced diluent may gradually deviate from the concentration range. Therefore, in the present embodiment, the concentration of the diluent is measured by the concentration measuring means 22. If the measured concentration of the diluent deviates from the predetermined concentration range, the proportional constant is corrected to make the concentration of the diluent fall back to the predetermined range. within the concentration range. By this feedback control, even when the operation of the device is just started or when the target value of the concentration of the diluent is changed, the proportional constant can be automatically changed to the optimum value. As a result, a dilution liquid adjusted to a predetermined concentration can be stably produced.

The configuration of the flow measurement means 21 is not particularly limited, and for example, a Karman vortex flow meter or an ultrasonic flow meter can be used. In addition, the flow measuring means 21 may be installed at a position where the flow rate fluctuation of the first liquid flowing in the first piping 11 can be monitored, and the installation position is not particularly limited. In addition, in the embodiment shown in the figure, the flow rate measuring means 21 is provided on the upstream side of the first pipe 11 from the connecting portion with the plurality of second pipes 13, but may be provided on the downstream side of the connecting portion. position to measure the flow rate of the diluent flowing through the first piping 11 . The reason is that the supply volume (flow rate) of the second liquid is much smaller than the flow rate of the first liquid, and the flow rate of the diluent can be treated as the flow rate of the first liquid.

The concentration measuring means 22 is not particularly limited as long as it can measure the concentration of the diluent as an electrochemical constant. For example, a conductivity meter, a pH meter, a resistivity meter, and an ORP meter can be used. (redox potentiometer), or ion electrode meter, etc. When the produced diluent is used for cleaning and cleaning the object to be treated for the purpose of antistatic and elimination of static electricity, it is preferable to use a conductivity meter and a resistivity meter as the concentration measuring means 22 . As shown in the figure, the concentration measuring means 22 is installed at a position on the downstream side of the first piping 11 from the connection portion with the plurality of second piping 13, and may be directly attached to the first piping 11 at this installation position, or may be It is attached to the bypass piping installed in parallel with the first piping 11 .

It can also be understood from Hagen-Bailey's Law that the accuracy of the supply amount (flow rate Q) of the second liquid is greatly affected by the pressure gradient ΔP at both ends of the second pipe 13 . Therefore, when the pressure of the connection part of the 1st piping 11 and the 2nd piping 13 fluctuates greatly, it becomes difficult to manufacture the dilution liquid adjusted to predetermined density|concentration stably. In order to monitor the pressure fluctuation|variation in this connection part, the pressure measurement means 23 which measures the pressure in the 1st piping 11 is provided as shown in figure. Therefore, the control unit 20 can calculate the target value of the pressure in the first tank 12a so that the concentration of the diluent becomes the target concentration based on the measurement results of the flow rate measuring means 21, the concentration measuring means 22, and the pressure measuring means 23, and perform the operation. Adjustment of the addition amount of the second liquid. The configuration of the pressure measuring means 23 is not particularly limited, and the installation position thereof is also at the position on the upstream side of the connecting portion with the plurality of second pipes 13 in the embodiment shown in the figure, but it can be measured at The pressure in the pipe of the connecting portion may be located on the downstream side of the connecting portion.

As described repeatedly so far, the flow rate Q of the second liquid flowing through the second pipe 13 is proportional to the pressure gradient ΔP across the second pipe 13 . Therefore, if the pressure gradient ΔP can be greatly changed, a wide range of supply amount (flow rate) of the second liquid can be realized, and it can be applied to a wide concentration range. However, practically, since the pressure applied to each of the grooves 12a and 12b has an upper limit, it is difficult to greatly change the pressure gradient ΔP, and the adjustment range of the addition amount of the second liquid is also limited.

On the other hand, according to Hagen-Bailey's Law, the flow rate Q of the second liquid is also proportional to the inner diameter D (4th power) of the second pipe 13, and inversely proportional to the length L thereof. In view of this point, in this embodiment, in order to realize a wide range of supply amount (flow rate) of the second liquid, the plurality of second pipes 13 are configured so that at least one of the inner diameter and the length is different from each other. That is, the plurality of second pipes 13 are configured to pass the second liquid at different flow rates from each other even when the pressure in each of the grooves 12a and 12b is constant because at least one of the inner diameter and the length is different from each other. . Thereby, the adjustment range of the addition amount of a 2nd liquid can be widened in the whole apparatus, and the dilution liquid of a wide concentration range can be manufactured.

The inner diameter of each second pipe 13 is not limited to a specific size, but in order to more precisely control the concentration of the diluent to be produced, the inner diameter of each second pipe 13 is preferably more than 0.1 mm and 4 mm or less, and more than 0.2 mm. And it is better to be below 0.5mm. The reason for this is that the flow of the second liquid in the second piping 13 tends to be a laminar flow (regular flow). That is, since the flow in the pipe is a turbulent flow (irregular flow), the above-mentioned Hagen-Bailey-Soy's law does not hold, and it is difficult to proportionally control the flow through the second pipe by the pressure gradient ΔP between the two ends of the second pipe. The flow rate Q of the second liquid in the piping. In other words, in order to maintain a good proportional relationship between the flow rate Q and the pressure gradient ΔP, the flow of the second liquid flowing through the inside of each second pipe 13 should preferably be a laminar flow. Note that, for details of the ideal range of the inner diameter, refer to Patent Document 1.

Also, the length of each second pipe 13 is not limited to a specific size, but if the length is too short, the flow rate in the pipe is easily affected, and it becomes difficult to proportionally control the flow rate of the liquid by the pressure gradient at both ends of the pipe. Moreover, if the length is too long, the installation of the piping becomes difficult, and the contact area between the piping and the liquid increases, which may increase the contamination of the liquid in the piping. Therefore, the length of each second piping 13 is preferably within a range of 0.01 m or more and 100 m or less, and more preferably within a range of 0.1 m or more and 10 m or less.

Furthermore, if the second piping 13 has an inner diameter of 0.1 mm or less and a length of more than 100 m, the resistance when the second liquid flows through the second piping 13 is likely to increase, although it depends on the combination. The pressure can easily become high pressure. Therefore, in terms of such an inner diameter and length, the selection of components (pipes, valves, etc.) constituting the device becomes difficult in consideration of the pressure resistance, which is not preferable. In addition, if the inner diameter of the second piping 13 exceeds 4 mm and the length is less than 0.01 m, the resistance when the second liquid flows through the second piping 13 is likely to be small, although it depends on the combination. The flow rate of the liquid is easily changed by slight changes in the pressure in the tank. Therefore, such an inner diameter and length will make the pressure control in the groove difficult and unsatisfactory.

The material and shape of the second pipe 13 are not particularly limited, and a flexible pipe made of resin can be appropriately used. Such resins include fluororesins such as PFA and ETFE, polyethylene-based resins, polypropylene-based resins, and the like, and fluororesins that are not easily eluted when the diluent produced is used for cleaning and cleaning of semiconductor wafers is particularly preferred. In addition, when the second liquid is a volatile liquid, it is preferable to use the second pipe 13 with low air permeability in order to suppress the fluctuation of the liquid concentration due to the volatilization of the liquid in the pipe and the diffusion to the outside. In this case, depending on the use of the produced diluent as described above, the oxygen contained in the diluent may have an adverse effect, so that the diffusion of oxygen in the air from the outside to the inside of the second piping 13 can be suppressed. , and the viewpoint of suppressing the rise of the dissolved oxygen concentration in the second liquid is also good.

The method of connecting the second piping 13 to the first piping 11 is not particularly limited as long as the first liquid and the second liquid are appropriately mixed. For example, it is preferable to connect the second pipe 13 to the first pipe 11 so that the front end of the second pipe 13 is located in the center of the first pipe 11, whereby the first liquid and the second liquid can be efficiently mixed. In addition, the plurality of second pipes 13 are preferably connected to the first pipes 11 individually from the viewpoint of a simple structure and a structure with few places where fluid accumulates.

In the illustrated example, four second pipes 13 are provided, but the number of the second pipes 13 is not limited to four, and can be appropriately changed to, for example, two, three, or five or more according to the concentration range of the diluent required. Accordingly, the combination of the inner diameter and the length is not limited to a specific combination, and can be appropriately changed. With regard to the combination of the inner diameter and the length, a combination in which only one of them is different is also conceivable. At this time, since the pressure applied to each of the grooves 12a and 12b has an upper limit as described above, from the viewpoint of further widening the adjustment range of the addition amount of the second liquid, it is preferable to combine those with different inner diameters. It can also be known from the following conditions that combinations of different inner diameters are suitable: According to the above-mentioned Hagen-Bailey-Sawyer's Law, for the flow rate Q of the second liquid flowing through the second pipe 13, the length L is affected by the power of 1, and the inner diameter D is reversed. The system is influenced by the power of 4. In addition, in the present embodiment, the supply of the second liquid system to the first piping 11 is carried out through one of the plurality of second piping 13 , but it may be possible to pass through a plurality of second piping 13 depending on the concentration range of the required diluent. Two or more of the second pipes 13 are performed.

As described above, in the present embodiment, during the normal operation of producing the diluent, the first supply mode of supplying the second liquid from the first tank 12a to the first piping 11, and the second liquid supplying the second liquid from the second tank 12b to the first pipe 11 are implemented. Switching of the second supply mode of the first piping 11 . Thereby, there is no need to replace the tank, etc., and there is no need to stop the operation of the apparatus, so that the production of the diluted solution can be performed stably. Hereinafter, the switching operation will be described by taking, as an example, the case of switching from the first supply mode to the second supply mode.

In the first supply mode, by opening the valve 19a connecting the tank pressurizing gas supply line 18a and the first tank 12a, the tank pressurizing gas (for example, nitrogen) is introduced into the second tank pressurizing gas supply line 18a through the tank pressurizing gas supply line 18a. 1 slot 12a. Then, the measured value (pressure in the first tank 12a) measured by the pressure gauge 19c is adjusted to the target pressure by the intake and exhaust mechanism 18b. In this way, the second liquid in the first tank 12a passes through the designated second piping 13, and is added to the first liquid in the first piping 11 by a predetermined addition amount. In addition, at this time, the following valves are all closed, that is, the valve 19b connecting the tank pressurizing gas supply line 18a and the second tank 12b, the valve 16a of the chemical solution supply line 16, and the chemical solution supply line 16 and the first tank. The valve 15a between 12a, the valve 15b between the chemical solution supply line 16 and the second tank 12b, the air valve 17a of the first tank 12a, and the air valve 17b of the second tank 12b are all closed. In addition, the second tank 12b is in a standby state in which a small amount of the second liquid is stored.

By supplying the second liquid from the first tank 12a to the first piping 11, when the liquid level in the first tank 12a is lower than the predetermined lower limit liquid level, the valve 16a of the chemical liquid supply line 16 is opened, and the second tank is opened. Atmospheric valve 17b of 12b. Then, the valve 15b between the chemical solution supply line 16 and the second tank 12b is opened, and the second liquid is supplied to the second tank 12b through the chemical solution supply line 16 and stored. Then, when the liquid level in the second tank 12b reaches a predetermined upper limit liquid level, the valve 16a of the chemical solution supply line 16, the air valve 17b of the second tank 12b, and the space between the chemical solution supply line 16 and the second tank 12b are closed. valve 15b. After that, the valve 19b connecting the tank pressurizing gas supply line 18a and the second tank 12b is opened, and the tank pressurizing gas is introduced into the second tank 12b through the tank pressurizing gas supply line 18a. At this time, the measured value measured by the pressure gauge 19c is adjusted to the target pressure by the intake and exhaust mechanism 18b. That is, while the pressure in the first groove 12a is maintained at the adjusted target pressure, the pressure in the second groove 12b is also adjusted to the target pressure. When the pressure in the second tank 12b reaches the target pressure, the valve 14b connecting the second tank 12b and the second piping 13 is opened, and then the valve 14a connecting the first tank 12a and the second piping 13 is closed. This completes the switching of the supply mode from the first supply mode in which the second liquid is supplied from the first tank 12a to the second supply mode in which the second liquid is supplied from the second tank 12b. After that, the valve 19a connecting the tank pressurizing gas supply line 18a and the first tank 12a is closed, and the first tank 12a is in a standby state until the next time the second liquid is replenished for the first supply mode.

In this switching operation, as described above, the supply of the second liquid system from the second tank 12b is performed after the pressure in the second tank 12b is adjusted to match the pressure in the first tank 12a. Thereby, even immediately after switching from the first supply mode to the second supply mode, the second liquid in the second tank 12b can be added to the first liquid in the first piping 11 by a predetermined addition amount. As a result, the variation of the addition amount of the second liquid can be suppressed as much as possible when the mode is switched, so that the variation of the concentration of the produced diluent can be suppressed as much as possible.

In the above example, when the second tank 12b is in the standby state, the atmospheric valve 17b is in the closed state. This is to suppress the entry of oxygen into the second tank 12b, and to suppress the dissolution of oxygen into the second liquid when the second liquid is subsequently replenished to the second tank 12b. However, the atmospheric valve 17b does not need to be in the closed state when oxygen dissolved in the second liquid in the second tank 12b is not a problem. In addition, when the second liquid is replenished to the second tank 12b and replenished to the extent that the gas component in the tank disappears, the atmosphere in the tank is exhausted from the atmospheric valve 17b, so that the infiltration of oxygen into the second tank can be reduced. In the liquid, the atmospheric valve 17b can be in any state of opening and closing.

In addition, in the above-mentioned example, the replenishment of the second liquid system to the second tank 12b is performed just before the end of the first supply mode, but the timing of replenishment is not limited to this. For example, the replenishment of the second liquid may be performed at any timing in the first supply mode, such as immediately after switching to the first supply mode. At this time, when the second liquid is a volatile liquid, in order to suppress volatilization of the second liquid, it is preferable to keep the atmospheric valve 17b closed after the replenishment of the second liquid.

In addition, in the first supply mode, if the supply of the second liquid is performed until the first tank 12a is used up, the tank pressurization gas will be stored in the second piping, and when the next supply mode is switched to the first supply mode, the gas It will be supplied to the first piping, and the concentration of the produced diluent may fluctuate. Therefore, switching from the first supply mode to the second supply mode is preferably started before the first tank 12a is used up as described above.

In the diluent production apparatus 10 of the present embodiment, the supply of the first liquid to the first piping 11 may be temporarily stopped and the production of the diluent may be temporarily stopped during the interval of normal operation, such as when the diluent is not needed at the use end 1. Standby mode. At this time, for example, when switching from the first supply mode to the standby mode, it is considered that the pressure in the first tank 12a adjusted to the target pressure should be returned to the atmospheric pressure in consideration of safety. However, the pressure reduction to atmospheric pressure in this way is actually unfavorable from the following viewpoints.

That is, when the pressure in the first tank 12 a is reduced to atmospheric pressure, the gas component dissolved in the second liquid under high pressure generates bubbles, and the bubbles remain in the second piping 13 . Therefore, even if the 1st tank 12a is pressurized again after the normal operation is restarted, the second liquid will not be added, and the first tank 12a will be in an over-pressurized state. After that, air bubbles escape from the second piping 13, and the second liquid can be added to the first liquid again. However, since the second liquid is added rapidly at this time, it may not be possible to adjust the amount of addition well until the concentration of the dilution liquid to be produced. It takes time to become stable. The influence caused by such bubbles is the first discovery by the inventors of the present application.

Therefore, in the diluent manufacturing apparatus 10 of the present embodiment, even if, for example, the first supply mode is switched to the standby mode, the pressure in the first tank 12a is preferably adjusted and maintained at a pressure higher than atmospheric pressure. Thereby, generation of bubbles in the gas component dissolved in the second liquid can be suppressed. As a result, the addition amount of the second liquid can be satisfactorily adjusted after the first supply mode is restarted. In addition, especially when the second liquid is a volatile liquid, in order to suppress volatilization of the second liquid and suppress concentration fluctuations, the pressure in the first tank 12a in the standby mode is preferably higher than atmospheric pressure and higher than that of the second liquid. The saturated vapor pressure of the liquid is preferably higher. However, depending on the combination of the second liquid and the tank pressurizing gas, the tank pressurizing gas may dissolve into the second liquid during normal operation. Therefore, in such a case, the pressure in the first tank 12a in the standby mode should be determined in consideration of the solubility of the tank pressurizing gas in the second liquid in addition to the saturated vapor pressure of the second liquid. On the other hand, in consideration of the good addition amount adjustment that can be restarted more quickly after restarting in normal operation, even in the standby mode, the pressure in the first tank 12a can be maintained at the same state as in the first supply mode that has been adjusted to the target pressure . Such adjustment is particularly suitable when the second liquid is water obtained by dissolving electrolytes and gases, such as carbonated water and hydrogen-rich water.

(Second Embodiment) Fig. 2 is a schematic configuration diagram of a dilution liquid manufacturing apparatus according to a second embodiment of the present invention. Hereinafter, about the same structure as 1st Embodiment, the same code|symbol is attached|subjected to the drawing and the description is abbreviate|omitted, and only the structure different from 1st Embodiment is demonstrated.

The present embodiment differs from the first embodiment in that the function of the second groove 12b is changed. Specifically, the second tank 12b is not connected in parallel with the first tank 12a, but is connected in series with the first tank 12a via the connection line 31 . More specifically, the second tank 12b is connected to the first tank 12a so that the second liquid in the second tank 12b is supplied to the first tank 12a by the head pressure. In view of the above, the valves 14a, 14b, 15a, and 15b of the first embodiment are omitted, the plurality of second pipes 13 are provided only between the first tank 12a and the first pipe 11, and the chemical solution supply line 16 is only connected to the second tank 12b. connect. Moreover, the pressure gauge 19c is installed in the 1st tank 12a, and the valve 31a and the check valve (not shown) are installed in the connection line 31.

Therefore, in the present embodiment, the second tank 12b functions as a temporary storage tank for temporarily storing the second liquid to be replenished to the first tank 12a. That is, during the normal operation of producing the dilution liquid, according to the liquid level of the first tank 12a, the second liquid is appropriately replenished from the second tank 12b to the first tank 12a, and as a result, the second liquid can be continuously supplied from the first tank 12a. liquid to the first piping 11. Thereby, the production of the diluent can be carried out continuously and stably, without the need to replace the tank and to stop the operation of the apparatus. Hereinafter, this supplementary operation will be described.

During normal operation, the tank pressurizing gas (for example, nitrogen gas) is introduced into the first tank 12a through the tank pressurizing gas supply line 18a, and the measured value (the first tank) measured by the pressure gauge 19c is measured by the intake and exhaust mechanism 18b. 12a) is adjusted to the target pressure. In this way, the second liquid in the first tank 12a is added to the first liquid in the first pipe 11 through the designated second pipe 13 in a predetermined amount to be added. In addition, at this time, the following valves are all closed, that is, the valve 19b connecting the tank pressurizing gas supply line 18a and the second tank 12b, the valve 16a of the chemical solution supply line 16, the atmosphere valve 17b of the second tank 12b, And the valve 31a connecting the pipeline 31 is in the closed state. However, the state of the air valve 17b of the second tank 12b at this time is not limited to the closed state as in the first embodiment, and may be an open state as necessary.

By supplying the second liquid from the first tank 12a to the first piping 11, when the liquid level in the first tank 12a falls below a predetermined lower limit liquid level, the atmospheric valve 17b of the second tank 12b is opened. Then, the valve 16a of the chemical solution supply line 16 is opened, and the second liquid is supplied to the second tank 12b through the chemical solution supply line 16 and stored. Then, when the liquid level in the second tank 12b reaches a predetermined upper limit liquid level, the valve 16a of the chemical solution supply line 16 is closed, and the atmospheric valve 17b of the second tank 12b is closed. After that, the valve 19b connecting the tank pressurizing gas supply line 18a and the second tank 12b is opened, and the tank pressurizing gas is introduced into the second tank 12b through the tank pressurizing gas supply line 18a. At this time, the measured value measured by the pressure gauge 19c is adjusted to the target pressure by the intake and exhaust mechanism 18b. That is, while the pressure in the first groove 12a is maintained at the adjusted target pressure, the pressure in the second groove 12b is also adjusted to the target pressure. When the pressure in the second tank 12b reaches the target pressure, the valve 31a of the connecting line 31 is opened, and the second liquid is transferred from the second tank 12b to the first tank 12a by the head pressure. When the transfer of the second liquid is completed, the valve 31a of the connection line 31 is closed, and the second tank 12b is in a standby state until the next replenishment operation.

In this replenishment operation, as described above, the transfer of the second liquid from the second tank 12b to the first tank 12a is performed after the pressure in the second tank 12b is adjusted to match the pressure in the first tank 12a. Thereby, when the second liquid is transported from the second tank 12b to the first tank 12a by the head pressure, the pressure fluctuation of the first tank 12a can be suppressed as much as possible, and the concentration fluctuation of the produced diluent can be suppressed as much as possible . In addition, in order to ensure that the second liquid is transported to the first tank 12a by the hydraulic head pressure, the bottom surface of the second tank 12b is preferably located at a higher position than the top surface of the first tank 12a.

In the above example, the second liquid is stored until the liquid level in the first tank 12b in the second tank 12b falls below the predetermined lower limit liquid level, but it is not limited to this timing, and can be performed at any timing. At this time, when the second liquid is a volatile liquid, in order to suppress volatilization of the second liquid, it is particularly preferable that the atmospheric valve 17b is kept closed after the second liquid is replenished. Similarly, the transfer of the second liquid from the second tank 12b to the first tank 12a may be performed at any timing after the second liquid is stored in the second tank 12b. However, if the supply of the second liquid is performed until the first tank 12a is used up, the tank pressurization gas will accumulate in the second piping, and the gas will be supplied to the first piping, and the concentration of the produced diluent may fluctuate. Therefore, in order to continuously supply the second liquid from the first tank 12a, it is preferable to start the transfer of the second liquid from the second tank 12b to the first tank 12a at least at the above-mentioned timing, that is, before the first tank 12a is used up. [Example]

Next, an example corresponding to the second embodiment described above will be described with reference to the flowchart shown in FIG. 3 . In the flowchart of FIG. 3, the same reference numerals as those shown in FIG. 2 denote the same configuration as that of the second embodiment.

(Example 1) In this example, dilute ammonia water was produced as a diluent using the diluent production apparatus 10 having the configuration shown in FIG. 3, and the electrical conductivity of the dilute ammonia water was measured.

The second piping 13 uses five ETFE-made pipes A to E (pipes A and B: article number "7009", pipes C to E: article number "7010", all of which are different in at least one of inner diameter and length. Flom Corporation). The inner diameter and length of each of the tubes A to E are as follows. Tube A Inner Diameter: 0.2mm, Length: 3m Tube B Inner Diameter: 0.2mm, Length: 1m Tube C Inner Diameter: 0.3mm, Length: 1m Tube D Inner Diameter: 0.3mm, Length: 0.5m Tube E Inner Diameter: 0.3mm, length: 0.3m

In addition, the 1st piping 11, the 1st groove|channel 12a, and the 2nd groove|channel 12b are made of PFA, respectively.

Ultrapure water with a resistivity value of 18 MΩ･cm or more and a total organic carbon (TOC) of 1.0 ppb or less was used as the first liquid, and water was passed through the first piping 11 at a flow rate of 40 L/min and a water pressure of 0.35 MPa. 29 wt % of ammonia water (electronic industry, manufactured by Kanto Chemical Co., Ltd.) was used as the second liquid, and nitrogen gas was used as the tank pressurizing gas introduced into the first tank 12a.

For each of the tubes A to E, a conductivity meter (product number "M300", manufactured by METTLER TOLEDO Co., Ltd.) was used to measure the pressure when the pressure in the first tank 12a was changed and the amount of ammonia added to the ultrapure water was changed. The conductivity of dilute ammonia water. 4 is a graph showing the measurement results at this time. The horizontal axis represents the amount of ammonia water added to the ultrapure water, and the vertical axis represents the conductivity of the obtained diluted solution (diluted ammonia water).

Ammonia water is a weak base, and in a low concentration region, the change in conductivity with respect to the addition amount is large, but in a high concentration region, the change in conductivity with respect to the addition amount becomes slow. Therefore, the minimum addition amount of ammonia water in tube A and the conductivity of the diluent at this time are 0.015 mL/min and 1.2 μS/cm, respectively. In contrast, the maximum addition amount of ammonia water in tube E and the conductivity of the diluent at this time are The rates were 8.18 mL/min and 62.1 μS/cm, respectively. That is, in order to increase the conductivity of the diluent from 1.2 μS/cm (tube A) to 62.1 μS/cm (tube E) by about 50 times, the amount of ammonia added needs to be changed from 0.015 mL/min (tube A) to 8.18 The mL/min (tube E) changed approximately 545-fold. As can be seen from the graph of FIG. 4 , by using five pipes different in at least one of the inner diameter and the length, it is possible to correspond to the adjustment range of the addition amount of ammonia water as described above, and it has been confirmed that dilute products with a wide concentration range can be produced continuously. ammonia.

(Example 2) In this example, the diluent production apparatus 10 having the configuration shown in FIG. 3 was used, and the ultrapure water as the first liquid was introduced into the first piping 11 at a hydraulic pressure of 0.16 MPa, except that , to produce dilute ammonia water under the same conditions as Example 1. Then, the supply of the first liquid was temporarily stopped, that is, the production of the diluted solution was temporarily stopped, and the electrical conductivity of the diluted ammonia water before and after it was measured. In addition, the temperature of the ultrapure water and the ammonia water was adjusted to 23° C., and the target value of the conductivity of the diluent was set to 40 μS/cm. The measurement results at this time (the flow rate of the first liquid, the pressure in the first tank, and the time change of the conductivity of the dilute ammonia water) are shown in FIG. 5A . In addition, FIG. 5B also shows the measurement result of the case where the pressure in the 1st tank 12a returns to atmospheric pressure when the supply of the 1st liquid is temporarily stopped as a comparative example.

In this example, as shown in FIG. 5A , it was confirmed that even after the supply of the first liquid was restarted (after the normal operation was restarted), the conductivity of the diluent could be well adjusted. On the other hand, in the comparative example, as shown in FIG. 5B, when the supply of the first liquid is temporarily stopped, the pressure in the first tank 12a returns to atmospheric pressure, although the pressure in the first tank 12a is restored after the normal operation is restarted. Even higher than before, the conductivity of the diluent cannot be adjusted well. The reason for this is considered to be that when the supply of the first liquid is temporarily stopped in the present embodiment, the pressure in the first tank 12a is maintained at a pressure higher than atmospheric pressure, thereby suppressing the generation of air bubbles.

1‧‧‧Use end 10‧‧‧Diluent production device 11‧‧‧First piping 12a‧‧‧First tank 12b‧‧‧Second tank 13‧‧‧Second piping 13a‧‧‧Valves 14a, 14b ‧‧‧Valves 15a, 15b‧‧‧Valve 16‧‧‧Medical solution supply line (liquid supply means) 16a‧‧‧Valves 17a, 17b‧‧‧Air valve 18‧‧‧Pressure regulator 18a‧‧‧Slot Pressure gas supply line 18b‧‧‧Intake and exhaust mechanism 18c‧‧‧Inlet valve 18d‧‧‧Exhaust valve 19a, 19b‧‧‧valve 19c‧‧‧Pressure gauge 20‧‧‧Control part 21‧‧‧ Flow measuring means 22‧‧‧Concentration measuring means 23‧‧‧Pressure measuring means 31‧‧‧Connecting pipeline 31a‧‧‧Valve F2, F3‧‧‧Filter

Fig. 1 is a schematic configuration diagram of a dilution liquid manufacturing apparatus according to a first embodiment of the present invention. [ Fig. 2] Fig. 2 is a schematic configuration diagram of an apparatus for producing a diluent according to a second embodiment of the present invention. Fig. 3 is a flow chart of an apparatus for producing a diluent according to an embodiment of the present invention. Fig. 4 is a graph obtained by plotting the conductivity of the diluted ammonia water in Example 1 with respect to the addition amount of the ammonia water. 5A is a graph showing time changes of the flow rate of the first liquid, the pressure in the first tank, and the conductivity of dilute ammonia water in Example 2. FIG. [ Fig. 5B ] is a graph showing temporal changes in the flow rate of the first liquid, the pressure in the first tank, and the conductivity of the dilute ammonia water in the comparative example.

Claims (12)

A device for producing a diluent for producing a diluent of the second liquid by adding a second liquid to the first liquid, and supplying the diluent to a use end; comprising: a first piping for supplying the first liquid; The first tank stores the second liquid; the second pipe connects the first tank with the first pipe; the pressure adjustment part adjusts the pressure in the first tank, and the pressure in the first tank 2 The liquid is pumped through the second pipe and supplied to the first pipe; the control unit adjusts the flow rate of the first liquid or the diluent and the concentration of the diluent flowing through the first pipe according to the measured value Using the addition amount of the second liquid to the first liquid by the pressure adjustment part, the concentration of the diluent becomes a predetermined concentration; and a second tank, connected in series with the first tank, and temporarily stored for replenishment to the second liquid in the first tank. A device for producing a diluent for producing a diluent of the second liquid by adding a second liquid to the first liquid, and supplying the diluent to a use end; comprising: a first piping for supplying the first liquid; The first tank stores the second liquid; the second pipe connects the first tank with the first pipe; the pressure adjustment part adjusts the pressure in the first tank, and the pressure in the first tank 2. The liquid is pressure-fed through the second piping and supplied to the first piping; The control part adjusts the pressure of the second liquid with respect to the first liquid by the pressure adjustment part according to the measured value of the flow rate of the first liquid or the diluent and the concentration of the diluent flowing through the first pipe The amount added so that the concentration of the diluent becomes a predetermined concentration; and a second tank connected in parallel with the first tank and storing the second liquid to be supplied to the first piping instead of the first tank; the The pressure adjustment part can adjust the pressure in the second tank, and when the liquid level in the first tank is lower than a predetermined lower limit liquid level, the control part adjusts the pressure adjustment part to make the liquid level in the second tank lower than the predetermined lower limit liquid level. The pressure is the same as the pressure in the first tank, and then the supply of the second liquid from the first tank to the first piping is switched to the supply of the second liquid from the second tank to the first piping. According to the diluent manufacturing device of claim 1, wherein the pressure adjustment part can adjust the pressure in the second tank; when the liquid level in the first tank is lower than a predetermined lower limit liquid level, the control part The pressure in the second tank is adjusted so that the pressure in the second tank is consistent with the pressure in the first tank, and then the second liquid is replenished from the second tank to the first tank. The diluent manufacturing apparatus according to claim 1 or 3, wherein the first tank and the second tank are connected so that the second liquid in the second tank is supplied to the second tank by head pressure 1 slot. The diluent manufacturing apparatus of any one of claims 1 to 3 of the claimed scope includes a plurality of the second pipes, and at least one of the inner diameter and the length of the plurality of second pipes is different from each other. The dilution liquid manufacturing apparatus of claim 5, wherein each of the plurality of second pipes is connected to the first pipe. The diluent manufacturing apparatus according to any one of claims 1 to 3 of the scope of the application, wherein the first liquid is ultrapure water, and the second liquid is an aqueous ammonia solution or an aqueous tetramethylammonium hydroxide solution. The diluent manufacturing apparatus according to any one of claims 1 to 3, wherein, when the supply of the first liquid to the first piping is stopped to stop the production of the diluent, the control unit adjusts the first pressure in the tank so that the pressure in the first tank is maintained at a pressure higher than atmospheric pressure. The diluent manufacturing apparatus of claim 8, wherein the control unit adjusts the pressure in the first tank so that the pressure in the first tank is maintained at a pressure higher than the saturated vapor pressure of the second liquid . The diluent production apparatus of claim 8, wherein the control unit adjusts the pressure in the first tank so that the pressure in the first tank is maintained at the pressure adjusted before the production of the diluent is stopped . A method for producing a diluent, by adding a second liquid to the first liquid, to produce a diluent of the second liquid, and supplying the diluent to a use end; comprising the steps of: supplying the first liquid to the first liquid 1 piping; supplying the second liquid to the first piping adjusts the pressure in the first tank where the second liquid is stored, and sends the second liquid in the first tank through the first tank and the The second pipe to which the first pipe is connected and supplied to the first pipe; including measuring the flow rate of the first liquid or the diluent and the concentration of the diluent flowing through the first pipe, and determining the concentration of the diluent according to the measurement Adjust the amount of the second liquid added to the first liquid to make the concentration of the diluted liquid a predetermined concentration; temporarily store the second liquid in a second tank connected in series with the first tank; and The second liquid stored in the second tank is replenished to the first tank according to the liquid level in the first tank. A method for producing a diluent, by adding a second liquid to the first liquid, to produce a diluent of the second liquid, and supplying the diluent to a use end; comprising the steps of: supplying the first liquid to the first liquid 1 piping; supply the second liquid to the first piping, adjust the pressure in the first tank in which the second liquid is stored, and pass the second piping connecting the first tank and the first piping, the The second liquid in the first tank is pumped and supplied to the first piping; including measuring the flow rate of the first liquid or the dilution liquid and the concentration of the dilution liquid flowing through the first piping, and determining the concentration of the dilution liquid according to the The measured value adjusts the addition amount of the second liquid to the first liquid so that the concentration of the diluent becomes a predetermined concentration; stores the second liquid in a second tank connected in parallel with the first tank; and according to the The liquid level in the first tank is adjusted so that the pressure in the second tank is consistent with the pressure in the first tank, and the second liquid is supplied to the second tank from the second tank instead of the first tank 1 piping.

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