Membrane Filter Elements
Status: 06/2001/01 Operating Manual 31
6.3 Basic instructions for squeezing the membranes
The membrane filter elements are used to stabilise the filter cake during washing in the filter
chamber and to squeeze the filter cake to release additional filtrate. For this purpose a
suitable squeeze medium is fed under pressure behind the membranes following the
filtration phase.
Squeeze media
The following are used as squeeze media:
• compressible (e.g. air)
• incompressible (e.g. water)
Permissible squeezing pressure
The necessary squeezing pressure is generally determined by the dewatering properties of
the filter cake.
Here the maximum permissible squeezing pressure is dependent on the following
influences:
• permissible operating pressure of the press frame
• permissible pressure and temperature strain of the membrane filter elements
Danger
For safety reasons, water should always be the preferred squeeze medium for
squeezing the membranes.
- Water is a virtually incompressible medium.
- When using compressed air (or other gases), the compressed volume represents an
increased safety risk due to the technical work involved. If the closing force of the filter
press fails during squeezing with compressed gas, the expansion of the compressed
gas causes the filter press to open suddenly. This may result in damage to the filter
elements, filter press frame and other equipment. In such cases, the risk of serious
injury or even death to the operating personnel cannot be excluded.
Danger
Please obtain the permissible operating pressure of the filter press from the filter press
manufacturer. Impermissible overstressing leads to damage to the filter press frame, the
filter elements and other equipment. This presents a risk of serious injury or even death
to the operating personnel.
DANGER
DANGER
