Chemical Engineering Answers

During exponential phase in batch culture, the growth rate of a culture is proportional to the concentration of cells present. When Streptococcus bacteria are cultured in milk, the concentration of cells doubles in 50 min. If this rate of growth is maintained for 8h, what is the final concentration of cells relative to the inoculum level? 

Draw the illustration of main bioreactor types and explain the usage of these reactors in bioprocess engineering applications?(Compare the bioreactor types) 

Water is boiled at the rate of 25kg/h in a polished copper pan, 280mm in diameter at atmospheric pressure. Assuming nucleate boiling conditions calculate the temperature of the bottom surface of the pan.

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Question assume ideal and optimal operating conditions for the cycle and the re-heater. Air enters the cycle at 300K and 100kPa and it leaves the combustor at 975K and 1089kPa.

Calculate the (a) pressure (kPa) of the air leaving the re-heater

A wet organic pigment containing 36% by weight of CCl4 is to be dried to 6% by weight (wet

basis). The drier is to operate adiabatically with fresh plus recycle air entering the dryer with

0.45 kg of CCl4 per kg of dry air. The air leaves the dryer with 0.895 kg of CCl4/kg of dry air. The

capacity of the dryer is 250 kg of bone dry solid per hour. Calculate the ratio of the recycled air

to fresh air.

 The slabs of building boards contain 17% moisture by weight. They are dried to a water content 

of 1% by weight by circulating hot air over them. The fresh air contains 0.17 kg of moisture per 

kg. The exhaust air contains 0.075 kg of moisture per kg. How many cubic metres of fresh air at 

standard conditions must be used per 2000 kg of the wet building boards?

Power required to drive a ball mill with a particular ball load is proportional to (where, D = diameter of ball mill )

What is sphericity?

NMR spectrum of CH3-CH(OCH2CH3)2

NMR spectroscopy of CH3-CH(OCH3)2