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Jul 1, 2009 (Vol. 29, No. 13)

Expanding Disposable Depth-Filter Applications

Pall Focuses on the Improvement of Process Clarification Operations

  • Test Overview

    Click Image To Enlarge +
    Figure 2. Comparative filtration capacities for Supracap 100 capsules, Supradisc modules, and Stax capsules (at 1 bart dP)

    Test Fluid: Homogenized Yeast Test Solution, developed to be representative of a postcentrifuge mammalian cell type process solution.

    Depth Filter Medium: Seitz grade EKSP

    Filter Formats: Supracap™ 100 capsules, Supradisc™ II 16-inch modules, and Stax capsules (Table, Figure 2)

    Sheet Format: Single Layer

    Stax Port Configuration: Inlet, bottom of stack; Outlet, top of stack

    Feed Flow Rate: Constant at 300  L/m2/hr (typically the maximum flow rate used for biotech applications)

    Volumetric Throughput Target: 300 L/m2 (typical volumetric throughput value for biotech applications)

  • Trial Procedure

    Click Image To Enlarge +
    Filter details

    • Preflush all filters with filtered process water, 50 L/m2 at a minimum flow rate of 300 lmh.
    • Measure the pressure drop characteristics through all assemblies at flow rates of 100, 200, and 300 lmh.
    • Perform filterability trials at a constant feed flow rate of 300 lmh.
    • Record time, feed pressure, filtrate pressure, filtrate volume, and turbidity throughout the trial.
    • Continue trial until the pressure drop across the filter is a minimum of 1.0 bar (14.5 psi).
    • All instrumentation must be calibrated prior to test program.
    • Analyze samples at regular intervals for instantaneous turbidity measurement.

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