Small Wastewater Plant Treatment Operations for Class S
Know which plant you have
"Small wastewater plant" covers technologies whose process control has almost nothing in common. A
lagoon has no return sludge, no clarifier and no sludge age to control; an activated sludge
plant lives or dies by solids inventory; a fixed film process is controlled by hydraulic and
organic loading and recirculation; a sequencing batch reactor is activated sludge with a time
axis. The first act of competent operation is knowing which levers your plant actually has.
Preliminary treatment (headworks)
The headworks protects everything downstream, and it is where neglect shows up as equipment damage
weeks later.
- Screening removes rags, plastics and debris that would otherwise wrap impellers, blind
diffusers and fill digesters. Clean or maintain screens on a schedule; handle