The majority of filtration applications are relatively simple, and so tend to use standard textile fibres such as 2¼ denier polyester. 1 Gram of a 1 denier fibre has a length of about 9,000 metres. Similarly 2¼ grams of a 2¼ denier fibre also stretch to 9,000 metres. So, amazingly, a bale of a typical microdenier fibre (0.7 Denier) which weighs 200kg would stretch for 1,600,000 miles, that's 64 times round the planet.
So you can clearly see with finer fibres that the collection surface increases and the pore size decrease, both factors which enhance filtration efficiency.
The differences in fibre size
can be clearly seen here:
0.7 Denier
2.2 Denier
The above information only applies to polyester, for example, a 0.7 Denier polypropylene would be 10.4 Microns with a pore size of 13 as opposed to 8.5 and 15 as in the table below.
The following table illustrates how changing denier alters a felt: based on 500 g/m² polyester Fibrelox™ felt 1.8mm thick.
| Denier | Fibre diameter microns | Length of fibre per m² of felt | Surface area of fibre per m² of felt | Mean pore size microns |
|---|---|---|---|---|
| 0.7 | 8.5 | 3995 miles | 171 | 15 |
| 1.5 | 12.4 | 1864 miles | 116 | 22 |
| 2.2 | 15.0 | 1271 miles | 96 | 27 |
| 6.0 | 24.8 | 466 miles | 58 | 44 |
