Membrane Filter Elements
44 Operating Manual Status: 06/2001/01
7 Malfunctions and their causes
The following is a list of possible malfunctions and their causes.
Information
The following list makes no claim to completeness.
Fault Cause
Unequal cake
thickness
• Overfilling or underfilling of the chambers
• Incorrect filtration pressure
• Improperly sized feeding pump
• Differential pressures between the chambers
• Poor venting of the chambers
• Squeeze medium cannot escape
• Clogged feeding canals
• Clogged filtrate drainage holes
• Filter cloth blocking filtrate drainage holes
• Partially blinded filter cloths
• Different cloth qualities
• Fluctuations in the suspension composition
• Extreme fluctuation of the solid particles content
• Changes in the solid particles composition
Poorly dewatered
filter cakes
• Fault in the squeezing system
• Squeezing pressure is too low
• Squeezing time is too short
• Cakes are too thick
• Squeezing pressure rise is too rapid
• Changed composition of the suspension
• Improper conditioning
Frequent filter cloth
defects
• Unsuitable cloth material
• Insufficient cloth strength
• Chemical attack
• Abrasion from solids in the filtrate
Leaking of individual
chambers
• Dirty sealing edges
• Filter cloth wrinkles in sealing edge
• Partially new filter cloths
• Damage to the sealing edge of the filter element or the
filter cloth
• Incorrect closing pressure of the press
• Geometrical defect in the filter press
