The vessel dispersion number (D/μL) for plug flow is_________________?

Related Mcqs:

1. ‘N’ plug flow reactors in series with a total volume ‘V’ gives the same conversion as a single plug flow reactor of volume ‘V’ for _______________ order reactions?

   A. First
   B. Second
   C. Third
   D. Any

2. What is the dispersion number for a plug flow reactor ?

   A. 0
   B. ∞
   C. 1
   D. -1

3. In a/an _____________ vessel, the fluid enters and leaves following plug flow?

   A. Open
   B. Closed
   C. Open-closed
   D. Close-opened

4. The exit age distribution of a fluid leaving a vessel (denoted by E) is used to study the extent of non-ideal flow in the vessel. The value of ∫∞ 0 E.dt is____________________?

   A. 0
   B. 1
   C. ∞
   D. √2π

5. For identical flow rate and feed composition, X plug flow reactors (PER) in series with a total volume V gives the same conversion as single_______________?

   A. CSTR of volume V
   B. PFR of volume V
   C. CSTR of volume V/X
   D. PFR of volume V/X

6. For identical flow rate, feed composition and for elementary first order reactions, ‘N’ equal sized mixed reactors in series with a total volume ‘V’ gives the same conversion as a single plug flow reactor of volume ‘V’ for constant density systems. This is true, when the value of ‘N’ is ___________________?

   A. 1
   B. > 1
   C. ∞
   D. ≥ 1

7. With increase in the order of reaction (for all positive reaction orders), the ratio of the volume of mixed reactor to the volume of plug flow reactor (for identical feed composition, flow rate and conversion)?

   A. Increases
   B. Decreases
   C. Remain same
   D. Increases linearly

8. A pollutant P degrades according to first order kinetics. An aqueous stream containing P at 2 kmole/m3 and volumetric flow rate 1m3 /h requires a mixed flow reactor of volume V to bring down the pollutant level to 0.5 kmole/m3. The inlet concentration of the pollutant is now doubled and the volumetric flow rate is tripled. If the pollutant level is to be brought down to the same level of 0.5 k.mole/m3, the volume of the mixed flow reactor should be increased by a factor of_______________?

   A. 7
   B. 6
   C. 3
   D. 7/3

9. Three plug flow reactors (PFR’s) of 4, 5 & 6 m3 volumes are arranged in two branches as shown below in the figure. If the total feed rate is 300 tons/hr, then for the same conversion in each branch, the feed rate through branch II should be ______________ tons/hr ?

   A. 100
   B. 150
   C. 200
   D. 225

10. The size of plug flow reactor (PFR) for all positive reaction orders and for any given duty, is _____________________ that of mixed reactor?

    A. Greater than
    B. Equal to
    C. Smaller than
    D. Unpredictable from the data