A pharmaceutical suspension is synthesized so that a considerable amount of salt is formed during neutralization. This microfine suspension must be cleansed (washed out) of salt and further concentrated. Initial salt concentration is about 10% and the active ingredient is around 3.5%. The desired final concentration is almost no salt (< 0.1%) and 7.5% active ingredient.
The fineness of the suspension requires microfiltration. With conventional crossflow technology a further concentration of the suspension is impossible due to the high viscosity. Therefore, dynamic crossflow filtration is required. Systems with rotating ceramic discs have too low throughput and require 100 m² filter area. Hence the BoCross Dynamic Filter is the only available technology for this challenging separation task.
Two 8 m² BoCross Dynamic Filters are applied for thickening and washing of this viscous suspension achieving the target values of 7.8% active ingredient and 0.1% salt.
BoCross Dynamic Filter L8 – Hygenic Design
Units installed |
[ - ] |
3 |
Filter area per unit |
[m²] |
8 |
Material |
[ - ] |
1.4435 (316 L) |
Foot print per unit |
[m²] |
2 |
Year of commissioning |
[ - ] |
2 units in 2008 / 1 unit in 2016 |
Process and Operation Data
Solids content in feed |
[wt -%] |
3 |
Solids content in retentate |
[wt -%] |
7.8 |
Solids content in filtrate |
[g/l] |
Free of particles |
Washing out of salt |
[ - ] |
1 : 100 |
Operation pressure |
[bar, g] |
1.5 – 3.0 |
Product Data
Product | Iron hydroxide (pharmaceutical product) | |
Temperature | [°C] | 25 – 30 |