Membrane Filter Elements
Status: 06/2001/01 Operating Manual 25
Example 3 for calculating the closing forces for LENSER high-pressure
membrane filter elements up to 30 bar:
Filter element type KMZ 1500 UM HD bloc-PP/PP
Size 1500 mm x 1500 mm
•Values:
- Filter area A
F
= 3.765 m² (see data sheet)
1
- Total area A
G
= 1.5 m x 1.5 m = 2.25 m²
- Operating temperature 30 °C
- Maximum permissible filtration pressure from Graph 11 (page 62)
p
F
= 7 bar
- Maximum permissible squeezing pressure from Graph 16 (page 64)
p
N
= 30 bar
- Maximum operating pressure selected
p = p
N
= 30 bar
• Calculation of the closing forces:
Step 1: up to 50 % x 30 bar = 15 bar:
F
min
= 0.5 x 3.765 m² x 15 x 100 x 1.3 = 3670.9 kN
F
max
= 3670.9 kN + (2.25 m² - 0.5 x 3.765 m²) x 0.5 x 15 x 100
F
max
= 3946.5 kN
Step 2: 50 % to 66 % = 15 to 20 bar:
F
min
= 0.5 x 3.765 m² x 20 x 100 x 1.3 = 4894.5 kN
F
max
= 4894.5 kN + (2.25 m² - 0.5 x 3.765 m²) x 0.5 x 20 x 100
F
max
= 5262 kN
Step 3:
66 % to 83 = 20 to 25 bar
F
min
= 0.5 x 3.765 m² x 25 x 100 x 1.3 = 6118.1 kN
F
max
= 6118.1 kN + (2.25 m² - 0.5 x 3.765 m²) x 0.5 x 25 x 100
F
max
= 6577.5 kN
Step 4:
83 % to 100 % = 25 to 30 bar
F
min
= 0.5 x 3.765 m² x 30 x 100 x 1.3 = 7341.8 kN
F
max
= 7341.8 kN + (2.25 m² - 0.5 x 3.765 m²) x 0.5 x 30 x 100
F
max
= 7893 kN
Do not over- or undershoot the respective closing pressure.
1
You can obtain the relevant data sheets from LENSER.
Note
The determined closing force for the plate pack must be correctly transferred to the
closing device of the filter press. Ask the filter press manufacture to properly adjust the
closing forces.
Warning
Only high-pressure filter elements approved by LENSER may be used for a squeezing
pressure of 25 or 30 bar. Coordinate the operating conditions with LENSER.
Improper operation may cause property damage and injuries.
WARNING
