1. Durafil® / KPZ55 DE Filter Septums
This is a technical comparison of the Durafil® slotted membrane and the standard KPZ55, up to now the considered best septum for DE filtration on flat element DE filters
Both septums are made from 316 L stainless steel, the Durafil is in addition electro-chemically polished at the end of the production process.
Tom Thilert
Technology Director
PASS
Pall corporation

2. Dish Element Septums types
Durafil®
KPZ55 Screen
Candle (wedge wire)

3. Septum Pull Samples Samples were pulled to compare material strength
Durafil Schlitze quer
Durafil Schlitze längs
KPZ 55 Schuß quer
KPZ55 Schuß längs

4. Pull along the Slits

5. Pull across the Slits

6. Pre-Coat Build-up on Durafil® / KPZ55
Cake builds up on the membrane surface
Particles are retained in the depth of the screen before precoat starts
Durafil®
Screen

7. Particle Trajectory & Cake Build-up
Durafil®
KPZ55
Stabilized DE-bridges

8. Pre-Coat on Durafil® / KPZ55
80 g/m² g/m² g/m² g/m²
Durafil®
100% Coverage
KPZ55
80 g/m² g/m² g/m² g/m²
100% Coverage

9. Particle separation; Durafil® and normal (KPZ55) filter screen
Erläuterung des Kurvenverlaufes: Bedingt durch die Messmethode verläuft die Trennkurve nicht exakt au die Null. Die Auflösung reicht nicht aus, um den scharfen Knick zwischen 0µm – 7µm darzustellen. Die gesrichelte Linie zeigt somit den Verlauf des Trenngrades im unteren Bereich.

10. KPZ55 Filtration Compared to Durafil®
0,2
0,4
0,6
0,8 1
1,2
1,4
Haze 12°
Haze 25°
Haze 90°
Particles * 10Exp5
Parameter
Value
KPZ55
Durafil®

11. Comparison Durafil® / KPZ55
Particle Counts with Durafil® / KPZ55, High Gravity Bier
10000
100000 00 30 60 90
120
150
180
210
240
270
300
330
360
Time [min]
Particles > 2µm [ 1/100ml]
screen
Durafil®

12. Comparison Durafil® / KPZ55
Turbidity with Durafil® and KPZ55, High Gravity Beer
0,0
0,2
0,4
0,6
0,8
1,0
1,2
1,4
1,6
1,8
2,0 00 30 60 90
120
150
180
210
240
270
300
330
360
Time [min]
turbidity [EBC]
KPZ55
Durafil®

13. Durafil® Inlet Side 10x

14. Durafil® Discharge Side 10x