August AT-10, Manual

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WASTEWATER TREATMENT
PLANT MODEL AT6 - AT50
16 15
Removal of excess sludge
If the amount of sludge in the biological reactor of the Unit exceeds 600 ml of sludge/1 l of water, the
excess sludge must be removed from the Unit. The intervals and amount of removal depend on the
load on the Unit. As the age of the sludge in the Unit is at least 30 days, it means that the sludge is
aerobically stabilised and harmless.
IMPORTANT:
For high groundwater level, the Unit tank may not be completely emptied, as the Unit
may be raised or the tank walls may be deformed (crushed).
Process of excess sludge removal from the Unit
• Blower is off. Aeration and agitation in the biological reactor is stopped. Also, the operation of air
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lifts 1, 2 and 3 is stopped.
• The contents of the biological reactor must be settled for 30 minutes. The settled sludge must then
be pumped out of the bottom of the biological reactor chambers.
• Make sure that the water level between the biological reactor chambers during the removal does
not exceed 15 cm, otherwise it may result in damage to the internal partitions of the Unit.
• After removal, the biological reactor chambers must be filled with water to the previous level.
When filling with water, all chambers must be filled evenly, maintaining the water level difference
between the chambers up to 15 cm.
• The sludge concentration in the biological reactor of the Unit after removal must not be less than
300 ml/l.
• The pump pipe for pumping excess sludge must be placed carefully into the biological reactor of the
Unit without damaging the aeration elements or other internal equipment.
The maintenance manual is part of the technical documentation of the Unit. It is very important to
record all the defects, their removal, replacement of components and maintenance operations; for
example, sludge suction date, amount of surplus sludge removed, etc. Also, make sure to record the
visits of the Manufacturer or his representatives authorised to service the Unit. This is confirmed by
the signatures of the responsible persons.
The maintenance manual of the Unit must be completed responsibly and, at the request of the
Manufacturer or its authorised representative, submitted to the Manufacturer or its authorised rep
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resentative, for example, in case of claims for the operation of the Unit and/or upon arrival of the
Manufacturer or its authorised representative entitled to perform the maintenance of the Unit. If
the maintenance manual is not submitted to the Manufacturer or its authorised representative to
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gether with the claim on the operation of the Unit, such claims shall not be accepted and shall not
be investigated.
• UNIT MAINTENANCE MANUAL
example