What is the role of bacteria in Biogas Production?
Biogas is generated when bacteria degrade biological material in the absence of oxygen, in a process known as anaerobic digestion.
Bacteria in Biogas Production!
Anaerobic digestion depends on the biological activity of relatively slowly reproducing methanogenic bacteria. These bacteria must be given sufficient time to reproduce, so that they can replace cells lost with the effluent sludge, and adjust their population size to follow fluctuations in organic loading.
If the rate of bacteria lost from the digester with the effluent slurry (Effluent is the liquid discharged from any source. Effluents can create from municipalities, industries, farms, ships, parking lots and camp grounds and a viscous, semi–solid mixture of bacteria, virus‐laden organic matter, toxic metals, synthetic organic chemicals, and settled solids removed from domestic and industrial waste is known as sludge waste.) exceeds the growth rate of the bacteria, the bacterial population in the digester will be"washed out" of the system.
This washout is avoided by maintaining a sufficient retention time for solids ensuring that the bacterial cells remain in optimal concentration within the digester.
The number of days the feed material is required to remain in the digester to begin gas production is known as Hydraulic Retention Time (HRT) – It is the most important factor in determining the volume of the digester; the larger the retention period, higher the volume.