For concentrating a fine-particulate special PCC product a BoCross Dynamic Filter with 6 m² filtration area is operated.
The calcium carbonate suspension is fed to the BoCross Dynamic Filter directly after precipitation with a feed concentration of 13 wt.-% (DS-content). In this state the feed suspension has a high viscosity and has to be thickened to an end concentration as high as possible.
The BoCross Dynamic Filter achieves an end concentration of DS = 40 - 43 wt.-%. This end concentration is higher than the solids content of a filter cake (DS = 37 wt .-%), which is formed by pressure filtration at a pressure difference of Dp = 6 bar.
The solids discharged from the BoCross Dynamic Filter completely satisfy the process targets in terms of
- high end concentration
- no air intake
- pastous consistency with spreadable flow behavior.
BoCross Dynamic Filter
| Units installed | | 1 |
| Filter area per unit | [m²] | 6 |
| Material | | 1.4571 |
| Filter drive power | [kW] | 30 (installed = 55) |
| Foot print |
[m²] | 2 |
| Year of commissioning | | 2007 |
Process and Operation Data
| Specific filtrate throughput | [ l/m² h ] | 180 - 200 |
| Solids content in feed | [ wt -% ] | 13 |
| Solids content in retentate | [ wt -% ] | 40 - 43 |
| Solids content in filtrate | [ g/l ] | Free of particles |
| Operation pressure |
[ bar, g ] | 3 |
Product Data
| Product | Calcium Carbonate - Special PCC Product | |
| Medium particle size x50 | [ µm ] | << 1 |
| Viscosity | [mPas] | 25,000 |
| Temperature | [°C] | 25 – 30 |