Patent ID: 6607669
Filing Date: 2003-08-19
Classification: B01D

Abstract:
An apparatus for high-precision separation of pharmaceutical or biotechnology liquids while maintaining a substantially constant trans-membrane pressure across, and a substantially constant feed rate into, a separation unit of the apparatus, comprising:a reservoir for containing a pharmaceutical or biotechnology liquid, the liquid containing filterable material dissolved or suspended within a carrier liquid; a separation unit having an inlet, a filtrate outlet and a retentate outlet, said separation unit receives the liquid to be filtered through the inlet and separates at least some of the filterable material therefrom which passes as filtrate through said filtrate outlet, and a retentate of the carrier liquid and residue filterable material passes from the retentate outlet; a processor-controlled pump unit which controls movement rate of the liquid through the filtration unit; a conduit system which, by operation of said processor-controlled pump, directs the liquid to be filtered from said reservoir to said inlet of the separation unit and from the retentate outlet for return passage to said reservoir; at least one detector positioned along a location of said apparatus downstream of the separation unit for monitoring a parameter of the liquid within said apparatus and for transmitting data on the parameter to the processor-controlled pump; at least one valve downstream of the separation unit for modifying pressure within said apparatus; said processor-controlled pump unit includes control logic which receives said data from said detector, calculates the trans-membrane pressure across the filtration unit from said data, compares the thus calculated trans-membrane pressure with a selected trans-membrane pressure for the pharmaceutical or biotechnology liquid undergoing high-precision separation, and if a deviation between the calculated and selected trans-membrane pressure occurs, signals said valve to operate to vary the pressure at said detector so that the calculated trans-membrane pressure is made to substantially coincide with the selected trans-membrane pressure; and a flow meter along said conduit system between said pump unit and said inlet of the separation unit, said flow meter monitors flow value thereat, which is transmitted to said control logic which directs the pump unit to modify the flow value to maintain a substantially constant feed rate into the filtration unit which substantially coincides with a selected flow value.