Question

Mixing in an anaerobic sludge blanket reactor is due to?

(a) Rapid change in water temperatures throughout the reactor

(b) Release of gases by the microbial populations

(c) Rapid change in medium temperature throughout the reactor

(d) Due to viscous medium

I had been asked this question by my school teacher while I was bunking the class.

This interesting question is from Oxygen Transfer in Fermenters topic in division Mass Transfer of Bioprocess Engineering

Answer 1

Right option is (b) Release of gases by the microbial populations

The best explanation: The upflow anaerobic sludge blanket reactor (UASB) is a single tank process in an anaerobic centralised or decentralised industrial wastewater or blackwater treatment system achieving high removal of organic pollutants. Bacteria living in the sludge break down organic matter by anaerobic digestion, transforming it into biogas. Solids are also retained by a filtration effect of the blanket. The upflow regime and the motion of the gas bubbles allow mixing without mechanical assistance.