Installation guide

6
Process and Plant Description
The EPS Bison ASP treatment plant has an inner central chamber and an outer settlement tank. The plant treats sewage using the
extended aeration principle in the central bio-zone chamber. A simple course bubble diffuser, housed in a draft tube, introduces the
air that provides the oxygen to the bacteria that then treats the sewage. The bio-zone retains the mixture of water, sewage and air
until a level of treatment has been achieved. The treated effluent then enters the conical clarifier tank where settlement takes place
and the settled solids are drawn back towards the draft tube with the diffuser in it and returned to the bio-zone. The effluent finally
leaves the plant over a weir that extends around the circumference of the tank at the outlet level. The movement of fluid through the
whole system is by gravity displacement. There are no moving parts in the treatment plant.
ASP GRAVITY
A) Inlet, flow from the house (s)
B) Bio-zone chamber
C) Flow around the draft tube
D) Treated effluent being settled
E) Settled bio-solids returning to the draft tube
F) Final effluent going over the weir
G) Effluent exiting the plant
H) De-sludging access point
ASP PUMPED
A) Inlet, flow from house(s)
B) Bio-zone chamber
C) Flow around draft chamber
D) Treated effluent being settled
E) Settled bio-solids returning to the draft tube
F) Final effluent going over the weir
G) Final effluent going into pump sump
H) Final effluent being pumped out of the plant
I) De-sludging access point