Reactor volume in anaerobic biodegradation process

[War-Saw]

hello,
today I faced a problem with explaining why in anaerobic process the volume of UASB reactor is smaller than volume in CSTR with the same amount of final product - biogas
Answer should contain characteristics like: difference in kinetics, concentration, rxn yield.

Can anybody explain me this topic? Or tell me in which book I can find the answer :)

 

[henlus]

UASB digesters has very short RT of few hours to few days. They can handle very large amount of substrates and the bulk of the substrate is liquid.