8. Operation and maintenance
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The following should be noted when removing sludge:
First
remove the floating sludge from the surface,
then
place the intake pipe on the floor
of the pit.
Around 10 cm of water should be allowed to remain in the pre-treatment section.
After emptying the pre-treatment section should be refilled with fresh water.
Maintenance by a maintenance specialist
8.3
The maintenance should be undertaken by a specialist company (experts)
1
. Depending on the
discharge class selected, it should take place at least twice (three times) a year (interval of ap-
prox. 4/6 months). The intervals and work defined by the local water authority in the licence is-
sued under water law also apply. The system owner should take out a maintenance contract
with a qualified specialist for this work.
Maintenance should include the following:
Inspection of the operating log to check for correct operation (nominal/actual compari-
son)
Check the air filter of the air compressor and the supply/exhaust air openings on the
control cabinet
Air compressor maintenance according to details provided by manufacturer (see
Annexes)
Function check on mechanical, electro-technical and other system parts key to opera-
tion, such as aerator, lifts, control unit, valves, alarm equipment and battery in power cut
detector
Check level of sludge in the sludge reservoir. If necessary, the operator must arrange for
the sludge to be removed (see Item 8.1),
Carry out general cleaning work, e.g. remove deposits
Check the structural condition of the system
Check sufficient aeration and ventilation
Analysis of the aeration basin:
1
Specialist companies are those not affiliated to an operator, whose staff (specialists) are suita-
bly qualified to operate and maintain small wastewater treatment systems through their profes-
sional training and from having received relevant qualification measures.