JPS6058530A - Method and apparatus for testing membrane filter - Google Patents

Abstract

PURPOSE:To test completeness of membrane filter readily and accurately, by increasing the pressure on the primary side by a gas, and checking whether the pressure reaches a specified judging value or not after the elapse of a specified time. CONSTITUTION:A two-way valve 29 is opened, a gas is supplied to the primary side of a housing 21 from a gas source 26. The pressure of the primary side is increased when there is no damage or poor mounting in the filter 20. When the pressure on the primary side reaches 2kg/cm<2>, the pressure increase is stopped for a specified time. The pressure is kept constant. After the elapse of a specified time, the pressure increase is restarted. When a specified time is elapsed after the restarting, whether the pressure on the primary side is larger than a specified judging value or not is automatically checked. When the normal state is judged, a normal lamp is turned ON, and a three-way valve 28 is switched- over.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for testing a membrane filter (membrane filtration 2:).

Membrane filters are used in the sterile filtration process for manufacturing other medical products such as IJDoba and Ichikawa Pharmaceutical, and are the perfect solution for filters. The valve point 1 test (hereinafter abbreviated as BPT), which is standardized in ΔS M, F316-70, is widely used as a method that can easily and reproducibly test I without destroying or contaminating it. BPT treats the pores of the filter as thin tubes, and measures the pressure using the relationship between the pressure expressed by the surface tension equation (1) below and the maximum radius of the pore. There is a method of determining the maximum radius of
An indicating pressure gauge (12) is connected to the next side of the housing (11) in which a ball valve (13) is connected, and gases such as air, nitrogen, carbon dioxide, etc. Connect the air bubble detection pipe (1G) to the secondary side of the housing (11), and place the tip of this pipe (16) into the container (17).
). Wet the L, T, filter (10) with a liquid such as distilled water or filtrate liquid - C hair■1?
The wire hole is filled with liquid by the 3' phenomenon, the valve (13) is turned on at an appropriate interval, and the primary side of the filter is gradually pressurized with gas. Then, while visually checking for liquid leakage from the housing, a person observes the tip of the bubble detection vibrator (16) and the bubble detection vibrator (16). When the downstream side of the filter (io) is pressurized with gas, as long as the pressure is relatively small, this pressure and the liquid in the wire hole will maintain equilibrium, and the liquid will not be removed from the wire hole by JJI. %8
1+ is possible, but when the pressure reaches a certain value, a liquid with a small diameter filter width is divided by n1 from the wire holes to the secondary side, and gas comes out to the secondary side through these filter holes. . This can be known by the generation of bubbles from the tip of the bubble detection vibrator (1G), and this intense pressure is referred to as valve point pressure (hereinafter abbreviated as BP pressure). The following surface tension equation (
There is a relationship expressed by 1).

r = l((2acos θ/-P) ・---・
-(1) where σ is the surface tension, θ is the contact angle, and k is the shape correction coefficient. Therefore, as above, BP
By measuring the pressure, the pore diameter of the filter (10) can be determined. However, with the above method, the vibe (
16) until air bubbles are generated.
And when observing the tip of the pipe (1G), bubbles were generated.
It is necessary to read the pressure of the plant, which is cumbersome and difficult to automate.

In addition, the integrity of the membrane filter is automatically checked at approximately 8% of the P pressure.
Measure the diffusion flow rate of a single gas to the secondary side when applying a pressure saw at 0% Pressure is applied intermittently to the primary side of a pressure saw or noilter (measuring the change in pressure on the pressure saw) by 131
] It has been proposed to know when the temperature has been reached. However, in the former case, there is a problem that the test value deviates by 5 degrees depending on the filtration area of the filter, and the error becomes large with small filters, and in the latter case, there is a problem that the measurement conditions differ due to the 6-slip of the housing. be.

In addition, in any case, it is necessary to set the above-mentioned 4T test conditions, the equipment δ becomes complicated and expensive, and the maintenance cost is 14.1g11(-1, 2J,
In addition, the test itself is conducted independently, but it is completely 4I+
The quality of quality is determined by people based on the measurement results.
',<4) (,■) Therefore, it is difficult to incorporate such a conventional device into a line as an in-line test device.

The purpose of the present invention is to provide a method for solving the above problems and easily and accurately testing the integrity of a membrane filter;
The object of the present invention is to provide an apparatus for carrying out this method.

A first aspect of the present invention is to backpressure the primary side of a membrane filter fixed in a housing and moistened with liquid with gas at a predetermined rate, and after a predetermined time elapses, the pressure on the primary side of the membrane filter is determined to be a predetermined value. A second aspect of the present invention is a method for testing a membrane filter, which is characterized by checking whether IKi has been reached, and the second aspect of the present invention is an apparatus directly used for carrying out the invention of the above method, which apparatus includes: A gas source is fixed in the housing and connected to the primary side of the membrane filter that is wetted with liquid. It is characterized by having an R pressure speed setting valve installed between the two sides, and an L valve 51 installed on the primary side of the membrane filter.

As a result of repeated research on the integrity test of membrane filters, the inventors discovered the following fact and completed this invention. In other words, when the pressure on the primary side of a defect-free filter moistened with liquid is increased with gas at a predetermined rate, the reason why the - downstream side reaches BP pressure is due to the amount of gas supplied from the - downstream side. The JJI output of gas to the next side is balanced, and the pressure on the -next side is kept constant tff JSJ1
, in this case, the time it takes for the primary side of the defect-free filter to reach 131 points is 31 months)
It is determined by the pressure increase rate (J is constant,
Therefore, the integrity of the filter can be easily and accurately tested by checking whether the pressure on the primary side has reached a predetermined determination value after a longer predetermined time has elapsed. It has been confirmed through experiments that there is no error in the measured values compared to the results of conventional BPT, and that the integrity of the filter can be determined reliably. Note that the above determination may be made by a person looking at the pressure h1 after a predetermined period of time has elapsed. In addition, the pressure on the primary side may be recorded on a recorder until a predetermined time has elapsed so that a person can make a judgment by looking at this, or the device may automatically make a judgment after a predetermined time has elapsed. good.

According to the method of the present invention, the pressure on the primary side of a membrane filter fixed in a housing and moistened with liquid is increased by a predetermined ratio 'c with gas, and after a predetermined period of time, the pressure on the primary side of the membrane filter reaches a predetermined determination. Since it is only necessary to check whether the value has been reached, it is not necessary to monitor the primary side pressure during pressurization, and the integrity test of the membrane filter can be performed easily and accurately. can. 7i, that is, even if the above judgment is made by a person,
Is it necessary to constantly observe the pressure 31J3 and the tip of the pipe for air bubble detection as in the past? (It makes the work much easier.Also, even if the above judgment is automatically made by the device, it is necessary to constantly observe the pressure 31J3 and the tip of the pipe for bubble detection.) It is possible to compare the pressure point of the device with a predetermined judgment value, so it is possible to compare the pressure point of the device with a predetermined judgment value.
(b) The configuration of the electronic circuit that performs the determination becomes extremely simple. Furthermore, since the gas source and pressure gauge are connected to the primary side of the housing, there is no need to connect a pipe for bubble detection to the secondary side, unlike conventional methods, making in-line testing easier. Become. In addition, the device according to the present invention is simple, comprising a gas source, an Fi pressure speed setting valve, and a pressure gauge, and as described above, its electronic circuit is also very simple, so it is inexpensive. It is easy to manufacture, easy to maintain, and easy to incorporate into a line as an in-line automatic test device.

When applying back pressure to the primary side of the membrane filter, when the pressure on the primary side of the membrane filter reaches a predetermined pressure that is smaller than the above-mentioned judgment value J), the pressure is stopped for a predetermined period of time, and during this time the membrane filter is It is desirable to check whether or not the pressure on the primary side decreases. In this way, it is possible to check for poor sealing of the housing or piping, poor wetting of the filter, etc.

The present invention will be described in detail below with reference to FIGS. 2 to 5.

Fig. 2 shows the test equipment on the A-no-line which is not drawn into the line. Connected to the next side. 1, that is, the cross joint (22) on the negative side of the housing <21)
One end of the joint (22) is connected, and an LL force detector (pressure it) (24) using an indicating pressure gauge (23), strain gauge, etc. is connected to the other two ends of the joint (22). A gas source (2G) is connected to the remaining end of the hand (22) via a vibrator (25), and a needle valve is connected to the vibrator (2!i) in order from the gas source (26) side. Boosting speed setting valve (27) using E10,000 switching solenoid valve (three-way valve) (27)
8) and a three-way solenoid valve (three-way valve) (29). One boat of the three-way valve (28) is open to the atmosphere. Pressure detector (24), three-way valve (28)
and the two-way valve (29) is connected to the control circuit (30),
An automatic recorder 1i131) is connected to the control circuit (30).

Next, the operation of the above-mentioned test apparatus will be explained by taking as an example a case where a membrane filter having a pore diameter of 0.2 μm is tested for integrity. In addition, cellulose ester, nylon 6
In the case of a hydrophilic membrane filter such as -6 or polyvinylidene fluoride, the BP pressure is approximately 3.5 kg/an' T ne al.

Before starting the test, the two-way valve (29) is closed and the three-way valve (28) is closed.
) is switched so that gas flows from the setting valve (27 side) to the three-way valve (29) side.
A person manually adjusts the setting valve (27) to obtain a predetermined pressure speed.
to a certain degree of opening. In this case, the voltage is increased at a rate of 0.1 Ω/min' per second. J. The filter (20) moistened with liquid is mounted in the housing (21) and d5<.

By pressing the start switch in this state, the next test will be automatically started, and during the test, the housing (21) will be continuously detected by the detector (24).
) is recorded as shown in Figures 3 to 5:
Recorded in z3o.

Note that J5 is shown in Figures 3 to 5, and the horizontal axis is time (sec
), vertical line 1III indicates the pressure (kg/cm') on the negative side of the housing (21), F).

If the start switch is not pressed, the two-way valve (29) is first opened and gas is supplied from the gas source (26) to the next side of the housing (21), causing damage to the filter (20) or improper installation. If there is no pressure, the pressure on the negative side will increase at the above rate as shown by the straight line (a) in Figure 3 J3 and Figure 4. 'J
Ru. Then, when the pressure horn on the negative side reaches 2k (1/Cjn'), the pressure is stopped for a certain period of time ([2=20S(IC)ti7 pressure. 20) If there is a moisture problem, check the primary side pressure while stopping the pressure increase.
(]/ Since it decreases from C111', an alarm is issued and the test is interrupted. straight line (b)
The pressure is maintained constant as shown by , and the pressure increase is resumed after the above-mentioned time (t2) has elapsed. Then, when a certain period of time (t3=60 sec) has elapsed after the acoustic pressure re-listening, it is automatically checked whether the pressure on the -next side is greater than a predetermined determination value (3 kg/C1n', ).

In the case of a defect-free filter with a pore diameter of 0.2 μm, the pressure on the primary side after restarting pressure increase is 1. J, , As shown by the straight line (C) in Figure 3, in the above 1.1j case l:, 't7- L/
, 13]] pressure (3, 51tg10n') is reached, and the IC 45 is held constant as shown by the straight line (d) in the figure. Then, the pressure (3.5 kg/[111') at the time when the above time ([3) has elapsed after the back pressure was resumed is the judgment value (3
Since it is larger than kQ/an'), it is determined to be normal, and after the normal lamp lights up, the swivel valve (28) is switched and the air valve (28) on the next side of the 1st housing (21) is switched on. ) is released into the atmosphere, and the test ends.

If the pore diameter of the filter is smaller than 0.2 μIll, for example, the pore diameter may be mistakenly set to 0.2 μIll. When a <5 μm filter is installed, the pressure horn on the primary side after re-listening to IJ and 4 pressures is shown in Figure 4 as a straight line.
The line that reached 2.4 kg/an') is a straight line (f) in the same figure.
Indicated by J: Sea urchins are maintained constant. Then, the pressure (2.4ko/
(2) Since f) is smaller than the judgment value (3 kg/cn'), it is determined that there is an abnormality, and an alarm is issued! After a certain period of time (t4=
=/IQsec) The pressure angle is maintained, the primary side gas is discharged at IJI in the same manner as above, and the test is completed.

If the filter is damaged or improperly installed, first check the r? The pressure on the primary side after the pressure starts is shown in Figure 5 by the curve (
Upward as shown in g)? A certain period of time (t
1 = 40sec) 2k<1/cm2 even after passing)
Since there is no error, it is determined that there is an abnormality. Then, when the alarm is issued, 171 gases are discharged from the primary side in the same manner as above, and the test is completed.

Although the device d3 and the L-bi method in the above embodiment are for performing an offline test, it is of course possible to incorporate a device like the above Jζ into the line to perform an in-line test. be.

υ゛However, 1! which is currently being carried out at each factory! I(α1
In a filtration system, by incorporating a pressure detector into the line in a sterile room, in-line tests can be automatically performed under sterile conditions. in this case,
It is possible to centrally monitor and record test results for the entire factory in one location. For example, a pressure sensor is installed on the primary side of the housing of multiple filters that are used many times over a long period of time, such as the most applicable filter for clean water for washing bottles or the air vent filter for distilled water tanks. By sharing other parts of the equipment with these noilers, periodic tests can be automatically performed in a short period of time without disassembling the line.

[Brief explanation of drawings]

Fig. 1 shows a pipe spindle of a conventional device for performing valve point dest; Figs. 2 to 5 show embodiments of the present invention; 3 to 5 are graphs showing three examples of test results, respectively. (20)...Membrane filter, (21)...Housing, (23)...Indicated pressure J1, (24)...
・Pressure detector (pressure side), (26)... gas source, (2
7)...Back pressure speed setting valve. Above Figure 1 2

Claims (3)

[Claims] (1) Pressurize the primary side of the membrane filter, which is fixed in the housing and moistened with liquid, at a predetermined rate with gas, and check whether the pressure on the primary side of the membrane filter reaches a predetermined judgment value after a predetermined time has elapsed. A method for testing membrane filters, which is characterized by examining whether (2) When the pressure on the primary side of the membrane filter reaches a predetermined pressure that is smaller than the above-mentioned judgment value J, the predetermined time has elapsed.
1. A method for testing a pre-1 filter as claimed in claim 1, characterized in that the pressure increase is stopped, and during this period, it is checked whether or not the pressure peak on the primary side of the membrane filter decreases. (3) A gas source connected to the primary side of the membrane filter that is fixed in the housing and moistened with liquid, and a gas source that is used to maintain the four-pressure velocity of the primary side of the membrane filter using this gas at a predetermined level. Test K W of a membrane filter characterized by having a pressure increase rate Ilf setting valve installed between the primary side of the membrane filter, and a pressure 81 installed on the primary side of the membrane filter.
l.