#Question id: 14637
#Section 1: Engineering Mathematics
The maximum value of 5 cos θ + 3 cosθ 
#Question id: 24084
#Section 5: Bioprocess Engineering and Process Biotechnology
#Question id: 11855
#General Aptitude
#Question id: 14202
#Section 5: Bioprocess Engineering and Process Biotechnology
In a fluidized-bed biofilm reactor, cells are attached on
spherical plastic particles to form biofilms of average thickness L = 0.5 mm.
The bed is used to remove carbon compounds from a waste-water stream. The feed
flow rate and concentration of total fermentable carbon compounds in the feed
are F = 2 l/h and S = 2000 mg/l. The diameter of the column is 10 cm. The
kinetic constants of the microbial population are rm = 50 mg S/cm3.
h and KS = 25 mg S/cm3 . The specific surface area of the
biofilm in the reactor is 2.5 cm2 /cm3 . Assuming
first-order reaction kinetics and an average effectiveness factor of n = 0.7
throughout the column, determine the required height of the column for effluent
total carbon concentration of S0i = 100 mg/l.
#Question id: 14247
#Section 5: Bioprocess Engineering and Process Biotechnology
A steam steriliser is used to sterilise liquid medium for fermentation.
The initial concentration of contaminating organisms is 108 per
litre. For design purposes, the final acceptable level of contamination is
usually taken to be 10-3cells; this corresponds to a risk that one
batch in a thousand will remain contaminated even after the sterilisation
process is complete. For how long should 1 m3 medium be treated if
the temperature is 121⁰C ________________.