Page 13 - Simplified Wastewater Treatment Fundementals_Trickling Filters.exe
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Trickling Filters
Zoogloeal Mass has 3 layers of biology: an outer layer, middle layer and inner layer.
✓ The outer layer contains aerobic cells (breathing oxygen).
✓ The middle layer contains facultative cells (can utilize either oxygen or carbon dioxide
to breathe).
✓ The inner layer is anaerobic cells (breathing only carbon dioxide).
These three communities of biology work well in removing carbon based organic material
within the time the wastewater trickles through the filter.
As zoogloeal mass is fed with wastewater, it grows in population (just like in an aeration
basin). As the zoogloeal mass grows, the slime layer gets thicker and thicker, eventually
sloughing off and flowing into the underdrain system. This excess zoogloeal mass is known
as humus. Sloughing humus is the Trickling Filter’s way of wasting excess population of
biomass.
