Membrane Filter Elements
Status: 06/2001/01 Operating Manual 41
6.5 Cake drying
The filter cakes can be air-dried. For this purpose, compressed air flows through the filter
cakes as when washing the filter cakes (thorough washing). Filtrate is discharged from the
capillaries of the filter cake by the air. This procedure can be carried out before, during or
at the end of membrane squeezing.
The optimum method can only be determined through experimentation. Please contact
LENSER should you have any questions.
6.6 Core blow
The slurry canal is often blown clear with air before opening the filter chambers.
The compressed air flows from the end plate in the direction of the head plate. The resulting
mixture of suspension and air is let off via conduits. The amount of air and duration of
blowing required depend on the specific conditions.
Factors which are decisive to the effectiveness of this process:
• diameter of the suspension canal
• length of the filter-press assembly
• viscosity of the suspension
• available air pressure
Note
• The thorough washing process encompasses a number of variations which,
however, cannot be covered here. Please contact LENSER.
• The permissible washing pressure is dependent on the operating temperature and
the filter element design (see Graphs 11 and 12, Page 62).
Caution
Discharge the resulting exhaust air in a suitable manner.
Route the vent line outside the danger area for persons.
Check the operation of the venting system at regular intervals. A blocked venting system
may lead to considerable property damage and serious injuries.
Warning
Filtration must be completed without interruption.
An alternating operating mode without cake release is not permitted within a filtration
cycle.
Note
It may be advantageous to flush the suspension canal with water before core blowing.
Always make sure that the membranes are still pressurised when cleaning the core.
Otherwise the suspension will enter the squeezed-out cake chamber.
CAUTION
WARNING
