ACO ClarA 19-38, Руководство по эксплуатации

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Operation manual
ACO Clara
6.4.3 Functions of air-lift pumps
The air-lift pumps for the pumping of raw sewage water
and the air-lift pump for the pumping of return sludge are
in continuous operation.
Air-lift pump for raw sewage water: the capacity of the air-lift pump
depends on the level of the sedimentation tank. If the volume in the
balancing chamber is not fully drained, then the waste water has to be
pumped to the activation tank.
We identify the choking of the air-lift pump as per continuous maximum
level in the primary sedimentation tank, together with waste water overf-
low to the activation tank via the by-pass pipe.
Air-lift pump for return sludge: The air-lift pump must be permanently
in operation with the constant flow rate set by the manufacturer.
The inactivity of the air-lift pump for return
sludge will seriously damage the entire
purification effect of the plant within 24 hours.
6.4.4 Tank Level of Mechanical Pretreatment,
Inlet Pipe
The inlet pipe must be free of all impurities.
There must be the same water level in all chambers. Sediment of solids
can develop in the first chamber. We recommend loosening it by means
of a stream of water.
The water level beyond the scum board, where the air-lift pump for the
pumping of raw sewage water is, must be free of gross impurities that
could cause it to clog.
Check the state of filling the tank with sediment.
If the sediment level in the tank reaches the level of the edge of the
overflow to the air-lift pump for raw sewage water it is necessary to
pump the whole tank volume immediately. It will become evident because
of the air-lift pump for raw sewage water pumping sewage water with a
high concentration of black digested sludge in the event that the air-lift
pump is clogged.
6.4.5 Level of Final Sedimentation Tank and
Outlet object
Floating sludge can occur on the surface of the final sedimentation tank.
When a higher quantity has accumulated this sludge can build up into a
continual layer with a thickness of ca. 10 cm. This layer does not need
to cause the quality of the treated water to deteriorate, but it makes it
impossible to perform a visual check of the final sedimentation tank.
Therefore it is necessary to remove it.
The outlet of the plant must be free of any sediment, matted material, or
other impurities.
6.4.6 Quality of Treated Water
Check the quality in the outlet of the plant, where the treated water
should be clearly visible without any floating impurities (e.g. flakes of
activated sludge).
!
6.4.7 Check of concentration of activated
sludge – sedimentation test
To perform the test you need a graduated cylinder with a volume of
1000 ml (to be supplied).
The sedimentation test manages to define simply an approximate con-
centration of activated sludge.
The activated sludge must not be grey or black in colour.
The correct colour is brown.
Procedure:
• In accordance with Section 6.5 put a sample of 1000 ml of activated
sludge from the activation tank into the graduated cylinder (the aerati-
on must be running in the activation tank).
• Put the graduated cylinder on a flat surface and wait for 30 minutes.
• Observe the boundary line between the settled sludge and separated
water after 30 minutes.
300ml
600ml
1l
300ml
600ml
1l
300ml
600ml
1l
300ml
600ml
1l
300ml
600ml
1l
300-600 ml, optimal concentration
of activated sludge
shows the proper concentration. No
removal of surplus sludge is required.
0-300 ml, low concentration of activated sludge
means an insufficient concentration of activated sludge
in the activation tank.
600 ml and more, high concentration of activated
sludge
means that there is too high a concentration of activa-
ted sludge in the activation tank and the surplus sludge
should be removed.
No activated sludge in sample
No activated sludge has developed. Such a state can
be considered as a natural one during initial plant ope-
ration or it can show improper plant operation.
No sedimentation of activated sludge
If no boundary line has developed between the sedi-
mented sludge and separated water, this means that
the activated sludge is not in good condition and has
bad sedimentation qualities. It could be a natural pro-
cess during the initial operation of the plant or could be
due to an incorrect load and eventually the occurrence
of too high a quantity of unsuitable matter on the inlet
side (disinfecting agents, toxic substances, acids etc.).
6.4.8 Check of Treated Water
Sample the treated water from the outlet object of the plant to a speci-
men holder with plain walls. The treated water should be free of undissol-
ved substances (e.g. flakes of activated sludge) and not be significantly
coloured or have a strong smell.