Filtration operation carried out by continuous increase of the inlet pressure of slurry, is called the _____________ filtration?

Related Mcqs:

1. The basic filtration equation is given as dt/dV = (μ/A ΔP). [(α .CV/A) + Rm], where, V is volume of the filtrate; A is the filtration area, a is specific cake resistance, μ is viscosity of the filtrate, and C is the concentration of the solids in the feed slurry. In a 20 minutes constant rate filtration, 5 m3 of filtrate was obtained. If this is followed by a constant pressure filtration, how much more time in minutes, it will take for another 5 m3 of filtrate to be produced? Neglect filter medium resistance, Rm; assume incompressible cake ?

   A. 10
   B. 20
   C. 25
   D. 30

2. A centrifugal filtration unit operating at a rotational speed of w has inner surface of the liquid (density ρL) located at a radial distance R from the axis of rotation. The thickness of the liquid film is δ and no cake is formed. The initial pressure drop during filtration is ___________________?

   A. ½w2 . R2 . ρL
   B. ½w2 . δ2 . ρL
   C. ½w2 . δρL (2R + δ)
   D. ½w2 . R . ρL(R + 2δ)

3. Addition of filter aid to the slurry before filtration is done to _______________ of the cake?

   A. Increase the porosity
   B. Increase the compressibility co-efficient
   C. Decrease the porosity
   D. Decrease the compressibility co-efficient

4. In continuous filtration (at a constant pressure drop), filtrate flow rate varies inversely as the__________________?

   A. Square root of the velocity
   B. Square of the viscosity
   C. Filtration time only
   D. Washing time only

5. The cake resistance increases steadily with the time of filtration in a plate and frame filter employing constant ______________ filtration?

   A. Rate
   B. Pressure
   C. Both A. & B.
   D. Neither A. nor B.

6. During filtration operation, the filtrate encounters the resistance of the ___________________?

   A. Filter medium
   B. Cake
   C. Channel carrying the slurry to the upstream side of the cake and filtrate away from the filter
   medium
   D. All A., B. and C.

7. Range of compressibility co-efficient of the commercial compressible cake obtained in filtration operation is_____________________?

   A. 0.01 to 0.1
   B. 0.1 to 0.3
   C. 0.2 to 0.8
   D. 0.2 to 0.4

8. Filter aids like asbestos, kieselguhr, diatomaceous earth etc. are used to increase the porosity of the final filter cake & reducing the cake resistance during filtration. Filter aid is_______________?

   A. Added to the feed slurry
   B. Pre-coated on the filter medium prior to filtration
   C. Separated from the cake by dissolving solids or by burning it off
   D. All A, B. & C.

9. With increase in drum speed, in a rotary drum filter, the filtration rate_______________?

   A. Increases
   B. Increases linearly
   C. Decreases
   D. Is not affected

10. The inlet pressure in a constant rate filtration____________________?

    A. Increases continuously
    B. Decreases gradually
    C. Remains constant
    D. None of these