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Operation and maintenance manual for
Hydrotech Drumfilter HDF501-series
6..FUNCTION
6.1.Intended.use
The filter is designed and manufactured to remove suspended solids from
non-pressurised water. The filter is not a pressure vessel.
6.2.Non-foreseen.use
If not approved by Hydrotech, the filter may not be used for other liquids than
water. The filter must not be installed in an area where there is an explosive
atmosphere or any other risk of explosion, e.g. high dust load.
6.3.Filtration.and.backwash.process
1. Water to be filtered flows by gravity into the filter panels from the centre
drum.
2. Solids are separated from the water by a microscreen cloth fitted on the
outside of the filter panels while the clean water passes through the cloth
to the outside of the drum.
3. AUTO mode - The solids collected on the inside of the filter cloth is
gradually impeding the flow of water through the drum.
The water level inside the drum begins to rise. When the water level
reaches the level sensor the drum rotation and the backwash starts.
HAND mode - Drum rotation and backwash is continuous.
4. Backwash nozzles spray clean rinse water from the outside of the filter
panels. The collected solids are washed off the filter panels into the solids
collection trough as the drum rotates.
5. The removed solids flow together with the backwash water out of the filter
by gravity.
Filter drum with panels
Backwash outlet
Filtered water
Washed off solids
Spraying nozzle
Filtered water outlet
Inlet
