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Menu 3: Sludge pump
(Sludge pump SLP=0 to 40 days, t=0 to 60 sec.)
This setting determines the weekly cycle of sludge pumping and the duration of the
pumping.
Note: This function is crucial only for MBR applications where solid material content must be
minimised in the Bioreactor. This function is not required for other applications. In these
other cases the sludge pump feature is deactivated on the controller. (SLP=0, corresponds to
factory settings)
SLP = 0 (days)/ t=0 min The sludge pump is not activated with this setting
SLP = 1 to 40 (days): The pump frequency is set from 1 to 40 days for 24h with this
setting. Then the sludge pump starts at specified period t. Aeration runs at the same
time. If the pump runtime is interpreted by "BR min – ", it restarts with "BR min + ". This
mode is left if the sludge pump has worked for the entire running period t.
Recommendation: The running time t of the sludge pump should be selected in such a
way so that the pump extracts out once a week 25% of the net bioreactor volume (V
BR,
use
).
Example of dimensioning for a grey water unit 300L/day :
V
sludge
= 0,25% V
br,use
= 25% x 300 L = 75Litres (each week)
Fig: Curve of the sludge pump
Pressure lost because of pipe height and liquid resistance:
H
Lost
=2,3m -> Q
max
=80l/min
Running time of the sludge pump: t
sludge
=V
sludge
/Q
max
= 60 sec. (each week)
Menu 4: Test menu
(Test menu for blower, suction pump, back flushing pump and sludge pump)
The blower (air), suction pump (suction pump) back flushing pump (back flush pump) and
sludge pump (sludge pump) can be separately controlled and tested via the test menu. The
test mode can be terminated at any time with NEXT/ENTER. The time until automatic stop
(max. 6 min) is shown on the display by a count-down stopwatch.
A test can be performed anytime, however there must be sufficient water for pump activation
(BR min +). If the water level falls below minimum, (BR min -) then the display shows that a
pump test is not possible.
