15
“Operation & Maintenance Manual”, “Discfilter HSF2600 series”
5. FUNCTION
5.
5.1 Intended use
The filter is designed and manufactured to remove solid particles in unpressurised water
flow systems. The filter is not a pressure vessel.
5.2 Non-intended use
Unless approved in writing by Hydrotech, the filter must not be used to filter liquids other
than water. The filter must not be installed in an environment with an explosive atmosphere
or another risk of explosion, such as high concentrations of dust.
5.3 Filtration and backwash process
A brief description of the process is given below.
1. The water to be filtered flows with gravity from the inside of the filter drum out to the
filter segments.
2. Solid particles are separated from the water using a filter medium attached to both sides
of the filter segments, whilst clean water passes through the filter medium to the outside
of the filter segment.
3. Operating mode AUTO
– The solid particles that accumulate on the inside of the filter
medium gradually reduce the water flow through the filter panel. The water level on the
inside of the drum begins to rise. When the water reaches the level sensor, drum rotation
and backwashing is started.
Operating mode REMOTE
– The filter is controlled as in AUTO
operating mode or with an external control (e.g. time-controlled drum rotation and back-
washing).
Service HAND
– Drum rotation and backwashing are started manually.
4. The backwash nozzles spray wash water on the outside of the filter panels. The solid
particles that accumulate are washed from the filter panels to the sludge channel, at the
same time as the drum rotates.
5. The removed particles and backwash water flow with gravity out of the filter.
Figure 5.1
Disc filter function.
Inlet
Bypass
Sludge/
reject water
Backwash
nozzles
Sludge
trough
Outlet
Filter
panels/
media
