HOBRAFILT® depth filtersheets are manufactured from raw materials that are harmless to health (various types of cellulose, high-quality diatomaceous earth, perlites and resins). The filter sheets are essentially three-dimensional depth filters characterized by the use of adsorbents (compounds with a large inner surface area). These can be imagined as a network of small chambers and channels of different lengths within the materials, in which the particles are trapped by impurities.
In contrast to mesh filtration (on a thin layer), in depth filtration the total filtration area is increased many times over due to the presence of the adsorbent and the impurities are trapped in the passages not only mechanically but also by means of adsorption forces. When using a combination of mechanical and adsorption action of the filter layer, the difference between the particle and pore size of the filter layer can be greater and the particles can still be gradually trapped on the walls of the cavities. The quantity of filtered solution is much greater with depth filtration than with mesh filtration because the filter surface is also larger.
The filter mechanism includes various types of particle interception and the filtration effect is ultimately achieved by combining them. These are mechanical filtration, electrostatic and electrokinetic adsorption. Below are the detailed specifications of the HOBRAFILT "N" series depth filtersheets.
HOBRAFILT® - Depth filter sheets Applications
| Grad der Reinigung | zu beseitigen | Filterschicht Art | nominale Rückhalterate | Menge l/m2/h | Max. Druckunterschied |
|---|---|---|---|---|---|
| Vorfiltrarion Reinigung |
grobe Schlämme | S100 N S 80 N S 60 N S 40 N S30 N |
11 μm 8 μm 6 μm 5 μm 4 μm |
1,000 l | 3 bar |
| Reinigungs-/ Klärmfiltration | Hefen feine Schlämme |
S 20 N S 15 N |
3 μm 2 μm |
800 l | 2 bar |
| Feinreinigungsfiltration | Hefen Bakterien |
S 10 N | 0,8 μm | 500 l | 2 bar |
| Keimreduzierte Filtration |
Reduktion von Keimen, Hefen und Bakterien | ST 9 N ST 7 N |
0,6 μm 0,4 μm |
350-400 l | 1,2 bar |
| Mikrobiologisch wirksame Filtration | Mikroogranismen und Schutz der Membrankerze | ST 5 N ST 3 N |
0,3 μm 0,2 μm |
300 l | 1,2 bar |
HOBRAFILT® - Depth filter sheets
| Typ der Schicht | Durchflussmenge | Nominale Rückhalterate (Micron) | Dicke (mm) |
|---|---|---|---|
| ST 3 N | 25-38 | 0,2 | 3,8 +/- 0,15 |
| ST 5 N | 44-67 | 0,3 | 3,8 +/- 0,15 |
| ST 7 N | 79-109 | 0,4 | 3,8 +/- 0,15 |
| S 10 N | 127-174 | 0,8 | 3,6 +/- 0,10 |
| S 15 N | 182-227 | 2 | 3,6 +/- 0,10 |
| S 20 N | 233-280 | 3 | 3,6 +/- 0,10 |
| S 30 N | 275-321 | 4 | 3,6 +/- 0,10 |
| S 40 N | 420-540 | 5 | 3,6 +/- 0,10 |
| S 60 N | 771-889 | 6 | 3,6 +/- 0,10 |
| S 80 N | 1076-1390 | 8 | 3,3 +/- 0,10 |
| S 100 N | 1278-1789 | 11 | 3,4 +/- 0,10 |
