Bioreactors

In a bubble column bioreactor, mixing and oxygen transfer occur primarily through

• Mechanical stirring

• Gas sparging

•  Pump circulation

• Peristaltic motion

Which bioreactor is most suitable for immobilized cell systems?

•  Stirred tank

• Airlift

• Packed bed

• Photobioreactor

The fluidized bed bioreactor differs from a packed bed bioreactor mainly because

• It uses fixed packing 

• It allows particles to move freely

• It does not require aeration

• It only operates in batch mode

The membrane bioreactor combines biological treatment with

• Ion exchange

• Membrane filtration

• Chemical oxidation

•  Heat sterilization

A photobioreactor provides an environment that optimizes

•  Enzyme reactions

•  Fungal spore production

• Microalgal photosynthesis

•  Bacterial fermentation

In a bubble column, gas hold-up and mass transfer are most affected by

• Column material

• Gas flow rate

• Temperature

• Nutrient concentration

The support matrix in a packed bed bioreactor serves to

• Prevent oxygen transfer

• Provide surface area for cell attachment

• Increase viscosity

• Inhibit microbial growth

A key advantage of packed bed bioreactors is

•  Easy sterilization

• High shear conditions

• High cell density and stability

• Rapid biofilm detachment

In a fluidized bed bioreactor, particles remain suspended due to

• High gas or liquid velocity

•  Low nutrient concentration

• Magnetic agitation

• Sedimentation

A membrane bioreactor is commonly used in

• Wastewater treatment

• Food preservation

• Drug crystallization

• Composting