JPH0258963B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a deaerator for removing gas dissolved in a liquid (dissolved gas), and more specifically to a deaerator for removing gas dissolved in a liquid. This invention relates to a degassing device in which a tube molded from a synthetic resin material that prevents gas is housed in a vacuum chamber, and a liquid containing dissolved gas is degassed while flowing through the tube.

<Prior Art> As this type of degassing device, one disclosed in Japanese Patent Application Laid-open No. 123785/1983 is known. In order to improve the degassing efficiency in such a degassing device, the inner diameter of the tube can be made narrower, the wall thickness can be made thinner, and the tube can be made longer. The pipe resistance of the liquid increases and it becomes difficult to flow, making it impossible to obtain the required flow rate. Therefore, if pressure is applied to the liquid to be degassed in order to obtain the required flow rate, not only will extra equipment be required, but the tube will easily burst, so there is a natural limit to the pressure that can be applied. Currently, the device is only applied to applications that require a relatively small flow rate, such as mobile phases in liquid chromatographs.

On the other hand, the degree of degassing and the required flow rate differ depending on the use of the liquid to be degassed. For example, when used in a liquid chromatograph, it is sufficient to constantly supply a constant amount of several ml of almost completely degassed water, and in the case of ultrapure water for cleaning used in the IC semiconductor manufacturing process, it is necessary to degas it to 0.3 ppM or less. More than 1 ton of water is required per hour, and in the case of washing water for washing medicinal bottles, the required amount is continuously required at a given time, ranging from several ml to several ml per minute. However,
As mentioned above, conventional deaerators of this type can achieve the required amount of deaeration, but none of them can continuously provide a flow rate as large as 1 ton per hour. When a large amount of water was required, such as pure water, a large-scale vacuum degassing tower was installed.

Therefore, it is conceivable to use multiple tubes that flow the liquid to be degassed and connect them in parallel to perform deaeration processing at a large flow rate. The amount fluctuates significantly, making it impossible to stably obtain the required amount of degassing.Furthermore, as the number of tubes increases, the fluctuations in flow rate and degassing amount become even more significant, and the overall size of the device increases. There was a problem.

<Problems to be Solved by the Invention> The present invention has been made in view of the above-mentioned problems in the prior art. It is an object of the present invention to provide a deaerator which can stably and continuously obtain a constant flow rate, is small and compact, does not take up much space, is easy to manufacture and handle, and is inexpensive.

<Means for Solving the Problems> The degassing device of the present invention that achieves the above object includes a vacuum chamber made of a synthetic resin material that allows only gas to pass through and blocks liquid from permeating, each of which has approximately the same inner diameter, wall thickness, and length. A plurality of tubes formed in the same direction are housed and installed, one end of each tube is connected in communication with the distribution port of an inflow distribution board having one inflow port and a plurality of distribution ports, and the other end of each tube is are connected to the above-mentioned accumulation ports of an outflow accumulation board having one outflow port and a plurality of accumulation ports to give a slight difference in the flow resistance of the liquid flowing through each tube, and to make the inflow distribution board An appropriate number of deaeration units are arranged so that the liquid to be degassed is distributed into each tube from the inlet of the tube and collected at the outlet of the outflow accumulation board, and the inflow ports of each deaeration unit are connected to each other. The feature is that the outlet ports are connected in parallel to each other.

<Example> Hereinafter, an example of implementing the present invention will be described based on the drawings.

The deaerator of the present invention basically includes a plurality of deaerators, each of which includes one vacuum chamber 1, a plurality of tubes 2, 2..., one inflow distribution board 3, and one outflow accumulation board 4. The degassing unit is composed of units A ₁ , A _{2 .} . . and will be explained in detail first with reference to FIGS. 1 to 5.

The vacuum chamber 1 is formed into a cylindrical shape using a vertical metal material, and has an upper and lower cover plate 1a and a lower cover plate 1b integrally covered on the top and bottom to form an airtight interior. A connection port 8 for connecting to a connection pipe 7 of a vacuum pump (not shown) and a mounting port 10 for a pressure sensor 9 are integrally provided on the cover plate 1a to communicate with the inside of the vacuum chamber 1, and an inflow distribution panel is provided. The inlet 3a of the chamber 3 and the outlet 4a of the outlet stack 4 are made to protrude, and the inside of the vacuum chamber 1 is depressurized using a vacuum pump. Further, inside the vacuum chamber 1, tubes 2 are housed and installed, and a partition plate 5 for supporting a large number of tubes 2 in blocks is installed. This partition plate 5 is formed into a circular plate shape with approximately the same diameter as the inside diameter of the vacuum chamber 1, and its center is supported horizontally by a support 11, with notches for guiding each tube 2 to an appropriate location. Grooves 12 and gas conduction holes 13 are bored.

Tube 2 is the liquid to be degassed (liquid to be degassed) a
It is used to degas dissolved gas from the liquid to be degassed during the distribution process, and is made of synthetic resin materials that allow only gas to pass through and block the permeation of liquids, such as tetrafluoroethylene resin materials and silicone resins. The inner diameter, wall thickness, and length are determined depending on the properties of the liquid to be degassed, the flow rate, the material, and the required amount of deaeration (degree of deaeration). In the experimental results,
The inner diameter of tube 2 is 0.2 to 12 mm, and the wall thickness is 0.2 to 1.0.
mm, length was 10 to 45 m, and the flow rate of the liquid to be degassed was 0.1 to 10.0 ml per minute, it was possible to degas to a nearly complete state. Therefore, based on the required amount of degassing, after determining the material, inner diameter, and wall thickness of the tube 2, the length of the tube 2 is selected and set based on actual measurements. In the experimental example, tube 2
is molded with tetrafluoroethylene resin material, and 0.3ppM (mg
O ₂ /) or less, the inner diameter of tube 2 should be 1.0 to 2.0 mm, and the wall thickness should be 0.2 to 2.0 mm.
When the tube was set to 0.5 mm and the length was 50 to 100 m, the maximum flow rate of the liquid to be degassed (the maximum flow rate that flows through the tube with almost no resistance) was 10 to 20 ml per minute, and the required amount of degassed was obtained. . In addition, when tube 2 is molded from silicone resin, even if the inner diameter and wall thickness are made larger than in the case of polytetrafluoroethylene resin and the length is shortened to 10 m, the required amount of liquid can be degassed. was obtained at a maximum of 20 to 40 ml per minute. Next, the required number of tubes 2 is determined based on the required flow rate of the liquid to be degassed. That is, if 1 ton of degassed liquid is required per hour, and the maximum flow rate per tube is 25 ml per hour, then the maximum flow rate per tube is 25 ml per hour.
1.5 (25 x 60 = 1500ml), so 667 bottles (1000
If a tube 2 with a size of ÷1.5≒667) or more is prepared, 1 ton of degassed liquid can be continuously obtained per hour.

The material, inner diameter, wall thickness, length, and required number of tubes 2 are determined, and each tube 2 is molded to the same length, and one end of the tube is connected to the inflow distribution board 3.
The other end is connected to the distribution port 3b of the outflow stacking board 4, and the other end is connected to the stacking port 4b of the outflow stacking board 4, and is wound in a spiral shape and housed in the vacuum chamber 1,
A slight difference is given to the flow resistance of the liquid to be degassed flowing through each tube 2, 2.... At that time, be careful not to bend or twist each tube 2, and make sure that the diameters and heights of the spiral bundles 2a, 2b, 2c of each tube 2 are different so that they can be accommodated and installed efficiently. They are housed and installed concentrically in a stacked manner. That is, in the illustrated embodiment, the central spiral bundle 2a
The spiral bundles 2b and 2c, each having half the height of the spiral bundle 2a, were stacked concentrically around the outer periphery of the spiral bundle 2a, and these were stacked one after another in the vacuum chamber 1 via the partition plate 5 as one block. It is something.

Furthermore, when each tube 2 is housed and installed in the vacuum chamber 1, in order not to impair the degassing efficiency in each tube, it is necessary to avoid contact between the tubes 2 and between the tubes 2 and the vacuum chamber 1 as much as possible. Desirably, for this purpose, spacer material 6 is interposed between the tube 2 and the inner wall of the vacuum chamber 1 and the partition plate 5, and between each tube 2. The spacer material 6 is formed into a flat plate shape or small piece shape using a resin foam material having open cells, etc. For example, the flat plate-shaped spacer material 6 is applied to the upper and lower inner walls and peripheral inner walls of the vacuum chamber 1 and the upper and lower surfaces of the partition plate 5. The tubes 2 are installed along each other, and a small piece-shaped spacer material is installed between the tubes 2.

The inflow distribution board 3 has one inlet port 3a for receiving the liquid to be degassed, and a distribution passage 3c for distributing the received liquid a to a plurality of distribution ports 3b, 3b, . . . It is equipped with a plurality of distribution ports 3b, 3b... for communicating and distributing the liquid to be degassed to the plurality of tubes 2, 2..., and the inflow distribution plate 3 itself is formed into a substantially disk shape, Each distribution port 3
b, 3b, . . . are arranged approximately radially on the circumferential surface of the inflow distribution board 3. In addition, each distribution port 3b, 3b
... may be arranged and formed at the lower surface position of the inflow distribution board 3.

The outflow stacking board 4 is formed into almost the same shape as the inflow distribution board 3, and includes a plurality of collecting ports 4b, 4b, . . . for receiving the degassed liquid b, and each collecting port 4b,
The accumulation path 4c communicating with 4b... and its accumulation path 4c
It has one outlet 4a communicating with the outlet.

The distribution ports 3b of the inflow distribution board 3 and the collection ports 4b of the outflow collection board 4 are arranged in the same number, respectively.
By connecting each distribution port 3b and accumulation port 4b with each tube 2, each tube 2,2
. . . to give a slight difference to the flow resistance of the liquid to be degassed flowing therethrough. In addition, in the illustrated embodiment, the inflow distribution board 3 and the outflow accumulation board 4 are partially overlapped and integrated and installed at the inner upper part of the vacuum chamber 1, but the inflow distribution board 3 and the outflow accumulation board 4
They may be molded separately and installed separately at upper or lower positions inside or outside the vacuum chamber 1, respectively.

Thus, one deaerator is constructed by combining an appropriate number of deaeration units A configured as described above depending on the required flow rate of the deaerated liquid. That is, if 1 ton of degassed liquid is required per hour, and one degas unit A has a processing capacity of 125 per hour, for example, 8 units (125 x 8 = 1000) degassing unit A ₁ , A ₂ …
A ₈ is used to connect the inflow ports 3a and the outflow ports 4a of the deaeration units A ₁ and A ₂ to each other in parallel through connection tubes 14, respectively. At this time, arranging the deaeration units A ₁ , A ₂ . The deaeration units A ₁ , A ₃ , A ₅ , A ₇ located therein and the deaeration units A ₂ , A ₄ , A ₆ , A ₈ located below do not have to be configured identically. That is, the vacuum chamber 1 of the deaeration unit A ₁ installed on the upper side and the vacuum chamber 1 of the deaeration unit A ₂ ... installed on the lower side are stacked with their insides communicating with each other, and as shown in FIG. The connecting pipe 7 of the vacuum pump and the pressure sensor 9 are attached only to the deaeration unit A ₁ installed in..., and the distribution board 15 and the accumulation board 16, which are configured almost the same as the inflow distribution board 3 and the outflow collection board 4, are installed. This is to have the facility set up. Then, the upper and lower degassing units
The inflow port 3a of each inflow distribution board 3 installed in A ₁ , A ₂ ... and the distribution board 15 are connected to each other through a connecting tube 14a, and the outflow port 4a of each outflow collection board 4 and the collection board 16 are connected in communication with each other. are connected to each other through a connecting tube 14b, and a deaeration unit A ₁ , which is installed on the upper side.
Each distribution panel 1 installed in the vacuum chamber 1 of A ₃ ...
Tubes 14 that connect 5 to each other and integrated panels 16 to each other.
They are connected in parallel to each other. Therefore, no matter how many deaeration units A ₁ , A _{2 .} . . there are, there is only one inlet for liquid a to be deaerated and one outlet for deaerated liquid b.

When the liquid to be degassed a is supplied from the inlet of the connecting tube 14 to each degassing unit A ₁ , A ₂ . . .
It is distributed to each deaeration unit A ₁ , A ₂ ..., and
In each deaeration unit A ₁ , A _{2 .} . . , the liquid to be degassed supplied from the inlet 3 a of the inflow distribution panel 4 is distributed to each distribution port 3 b , 3 b . , 2... At this time, since a slight difference is given to the flow resistance of the liquid to be degassed flowing through each tube 2, 2..., when the supply flow rate of the liquid to be degassed is small, the liquid to be degassed is There are tubes 2 that are distributed and tubes 2 that are not distributed. In other words, the maximum flow rate per bottle is, for example, 20ml per minute.
If 40 tubes 2 are used, a maximum of 800 ml (20 ml x 40 tubes) of degassed liquid B can be obtained per minute.
If 600 ml is supplied per minute from the inflow port 3a of the inflow distribution board 3, each distribution port 3b, 3b...
(In this case, there are 40 distribution ports 3b on the inflow distribution board) Distribute 15ml evenly (600ml ÷ 40 bottles = 15ml)
Instead, the liquid flows through each tube 2 only through two or three distribution ports 3b. This phenomenon is caused by the fact that the tubes 2 are housed in the vacuum chamber 1, that is, the height differences and winding conditions of the tubes 2 are not the same, and each tube is distributed from the inlet 3a of the inflow distribution panel 3. Mouth 3b, 3
b... and the distances from the outlet 4a of the outflow stacking board 4 to each stacking port 4b, 4b... Due to the additive effect of slightly different diameters, etc., the flow resistance of the liquid to be degassed flowing through each tube 2... is slightly different depending on the tube, so it depends on the flow rate of the liquid to be degassed. This is because the fluid flows in order from tube 2, which has the lowest flow resistance. However, each tube 2
The difference in flow resistance at Due to the difference, it will now be distributed to other tubes 2 that were hardly distributed. In this way, the minute difference in the flow resistance of each tube has the function of automatically selecting the number of tubes that will be effective for deaeration by increasing or decreasing the flow rate, and the pressure loss itself due to the overall flow can be reduced. It is adjusted almost constant.

Thus, the liquid a to be degassed is distributed from the connection tube 14 to each deaeration unit A ₁ , A ₂ . The degassed liquid b is discharged into the vacuum chamber 1 and degassed, and the degassed liquid b is passed through each deaeration unit A ₁ , A ₂ . 4c
The water is collected at the outlet 4a and distributed to a predetermined location through the connecting tube 14.

<Effects of the Invention> Since the degassing device of the present invention is configured in this manner, the liquid to be degassed flows appropriately through each tube in each degassing unit according to its flow rate, and flows through each tube. The liquid is degassed during the process, and since the amount of deaeration per tube in each deaeration unit is the same for each tube, the same amount of deaeration can be carried out over a given range from a few ml to theoretically infinity. At times, the required flow rate can be stably and continuously obtained.

Examples of data degassed using the deaerator of the present invention are shown in FIGS. 8a and 8b. In the figure, the vertical axis is the amount of degassing, expressed as the amount of oxygen dissolved in the liquid (mgO ₂ /), and the horizontal axis is the flow rate of the liquid to be degassed per minute (ml/min). appear. FIG. 8a shows an example in which distilled water is used as the liquid to be degassed, and FIG. 8b shows an example in which ordinary tap water is used. As is clear from this data table, as the flow rate of the liquid to be degassed increases, the amount of degassed drops somewhat, but it can be seen that almost the same amount of degassed liquid can be continuously obtained from 0.1 ml to 1300 ml per minute. Also, Figure 8c is the 8th
This is a data table in which distilled water similar to that in Figure A was used for degassing with a conventional degassing device (device disclosed in Japanese Patent Application Laid-open No. 123785/1985). However, with conventional deaerators, it was not possible to compare the same flow rate due to increased flow resistance, so this was done only at a small flow rate. In the figure, A indicates a case where the tube is short, and B indicates a case where the tube is long. As is clear from this data table, the degassing amount fluctuates widely as the flow rate increases, and the usefulness of the present invention will be understood by comparing it with the data table of FIG. 8a.

Moreover, the degassing device of the present invention has a very small and compact device (in the example, the vacuum chamber of the degassing unit has a height of 360 mm and an inner diameter of 240 mm), does not take up much space for installation, and is economical. The effects are significant.

Furthermore, it has a simple structure and is easy to manufacture, and can be provided at a much lower cost than conventional degassing towers, and at the same time, its maintenance and inspection are easy.

Therefore, the intended purpose can be achieved.

[Brief explanation of the drawing]

The drawing shows one embodiment of the deaerator of the present invention, and the first
The figure is a partially cutaway front view of one degassing unit, Figure 2 is a sectional view taken along line 2-2 in Figure 1, Figure 3 is a sectional view taken along line 3-3 in Figure 2, and Figure 4 is a sectional view taken along line 3-3 in Figure 2. 5 is a schematic diagram illustrating the relationship between the inflow distribution panel, outflow accumulation panel, and each tube in one deaeration unit, and FIG. 5 is a partially cutaway front view showing another embodiment of the deaeration unit installed on the upper side. Fig. 6 is a front view showing the entire degassing device of the present invention, Fig. 7 is a plan view thereof, Fig. 8a,
8b is a graph of data degassed by the deaerator of the present invention, FIG. 8a is an example in which distilled water is used as the liquid to be degassed, and FIG. 8b is an example in which ordinary tap water is used as the liquid to be degassed. FIG. 8c is a graph of data obtained by degassing with a conventional degassing device. In the figure, A ₁ , A ₂ , ...A ₈ are degassing units, 1 is a vacuum chamber, 2 is a tube, 3 is an inflow distribution board,
3a is an inflow port, 3b is a distribution port, 4 is an outflow stacking board, 4b is a collection port, and 4a is an outflow port.

Claims (1)

[Claims] 1 A plurality of tubes, each made of a synthetic resin material that allows only gas to pass through and blocks the permeation of liquid, each formed with approximately the same inner diameter, wall thickness, and length, are spirally wound and installed in a vacuum chamber, and each tube is housed in a vacuum chamber. One end of each tube is connected in communication with the distribution ports of an inflow distribution board having one inflow port and a plurality of distribution ports, and the other end of each tube is connected to an outflow distribution board having one outflow port and a plurality of accumulation ports. The tubes are connected to each other in communication with the above-mentioned accumulation ports, and the coefficient of friction due to the inner diameter and material of each tube, the height difference, the winding state, and/or the inflow port of the inflow distribution panel to each accumulation port of the outflow accumulation panel are determined. A slight difference is given to the flow resistance of the liquid flowing through each tube based on the difference in the distance between the tubes, and the liquid to be degassed is distributed and distributed from the inlet of the inflow distribution board into each tube to form the outflow accumulation. A deaeration system characterized by arranging an appropriate number of deaeration units configured to accumulate at the outlet of the panel, and connecting the inflow ports and the outflow ports of each deaeration unit in parallel with each other. Device.