Where it fits
The high-flow polypropylene capsule does clarification and pre-filtration: cell culture broth clarification, serum pre-filtration, gas pre-treatment, and guard duty ahead of electronic chemicals, developers and strippers. Its role is clear — hold the load here so the sterilising-grade or semiconductor-grade filter downstream can do the real gatekeeping.
Key characteristics
The multi-layer microfibre tightens layer by layer from the outside in: coarse solids are caught in the outer layers before fines reach the tight one. Against a single-density build, that gives far more dirt-holding capacity, and differential pressure climbs steadily instead of blinding all at once.
This is the widest operating window of the seven capsules — both temperature and pressure ratings sit clearly above the rest of the family, which saves a derating exercise on warm feeds or lines with plenty of pump head. As nominally rated depth media it is not bubble-point testable, so batch verification is by flow and differential instead.
Choosing between options
Among polypropylene capsules, and among capsule prefilters generally:
| Product | Media | Rating range | Reason to pick it |
|---|---|---|---|
| High-flow PP capsule (this) | Multi-layer polypropylene microfibre, graded pores | 0.1 – 10 µm | General pre-filtration for biotech and electronic chemicals; wide operating window, electronic grade available |
| Glass fibre capsule | Ultrafine glass fibre, three-dimensional depth | 0.5 – 20 µm nominal | Colloids and viscous feeds where dirt-holding comes first |
| Semiconductor PP CMP point-of-use capsule | Melt-blown or pleated polypropylene depth | 50 nm – 10 µm | CMP slurry at the point of use, where the abrasive size distribution must survive |
Operation & change-out
Short capsules are distinguished by size code, and both effective area and hold-up rise with the code. Depth polypropylene media itself holds liquid, so blow down with gas before draining if recovery matters. A single-use capsule cannot be backwashed or regenerated — change it at the differential threshold in the specification table.