US 5,353,630 AGranted

Apparatus for testing membrane filter integrity

AssigneesMemtec Japan Limited, Filtec Corporation

InventorsFusao Soda, Hidenobu Sawa

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Abstract

A membrane filter integrity test system includes a large volume mass-flow controller for rapidly supplying a larger amount of fluid to a primary side of a membrane filter under test, a small volume mass-flow controller for supplying a relatively small amount of fluid to the primary side of the membrane filter. The operation of the large volume mass-flow controller is stopped when the pressure at the primary side of said membrane filter reaches a predetermined level. This predetermined pressure is detected by a pressure sensor which senses the pressure at the primary side of the membrane filter. The pressure sensor responsively generates a detection signal corresponding to the sensed pressure at the primary side of the membrane filter. A main controller responsive to the detection signal from the pressure sensor controls the small volume mass-flow controller in a negative feedback loop manner for controlling the supply of fluid to the primary side of the membrane filter so that the pressure on the primary side of the filter is maintained at the predetermined value.

Claims6

Dependent claims

An apparatus for testing the perfection of a membrane filter, said apparatus comprising:

a large-flow controller for supplying a primary side of said membrane filter rapidly with a larger amount of a fluid;
a pressure detecting sensor for detecting the pressure at said primary side of said membrane filter and for responsively generating a detection signal;
a small-flow controller for supplying the primary side of said membrane filter with a smaller amount of said fluid;
a switching member for forming a fluid path for said fluid from said large-flow controller and said small-flow controller to said membrane filter, said switching member disconnecting said fluid path and forming an exhaust path for withdrawing said fluid in said primary side of said membrane filter
a main control unit responsive to the detection signal from said pressure detecting sensor to stop the operation of said large-flow controller when the pressure at the primary side of said membrane filter reaches a predetermined level, the main control unit then controlling said small-flow controller in a proportional/integral control manner to compensate the pressure decrease caused by said membrane filter to maintain said predetermined level, said main controller monitoring the amount of fluid flowing from said small-flow controller to said membrane filter to determine diffusion flow in said membrane filter.

2 more elements

Dependencies are inferred from the claim text.