3
The pneuma
�
c strategy breaks the linkage between backwash frequency and water loss and allows the
nitri
fica�
on capacity of the unit to be fully utilized. Frequent backwash sequences have proven
advantageous for op
�
mizing the nitri
fica�
on capacity of the unit. Numerous gentle scrubbing cycles
promote high rates of nitri
fica�
on by maintaining a healthy thin bio
fi
lm on the bead surfaces. Typical
backwash cycles occur once every three to six hours. In recircu
la�
ng bioclari
fi
er appli
ca�
ons, where the
High Pressure
PolyGeyser
®
Bead Filter operates concurrently as a clari
fier
and bio
fi
lter, total ammonia
nitrogen (TAN) levels below 0.3, 0.5 and 1.0 mg-N/l can be expected at feed loading rates of 0.5, 1.0 and
1.5 pounds feed per cubic foot of EN bead media (8, 16 and 24 kg-feed m
-3
day
-1
), respec
�
vely.
Table 5. High Pressure
PolyGeyser
®
Bead Filter Speci
fica�
ons