CROSS FLOW: The STRASSBURGER MicroCross®
In developing the STRASSBURGER MicroCross® system for wine filtration, we have achieved the goal of ensuring the best possible preservation of the aroma, quality, and characteristics of the product. The MicroCross® system can be used during the various stages.
Our PLC-controlled MicroCross® systems work fully automatically and stand out from the crowd due to their simple and safe operation. This process does not require any filter aids – which saves costs and protects the environment. Through backwashing and cleaning, the output performance can always be achieved again.
The MicroCross® in detail
- No filter aids required
- Compactly designed systems
- Increased performance due to “backwash”
- Simple and safe operation
The MicroCross® system is available in various automation levels. The automated versions are operated by a Siemens programmable logic controller:
- Fully automatic for 24 h operation with automated rinsing and cleaning intervals for large capacities.
- Available from 4 modules on up
- Semi-automatic via manual selection of the individual process steps (which then run automatically).
- Available from 4 modules on up
- Manual for small filtration capacities for unattended operation, but with manually operated valves.
- Available from 2 modules on up
High-pressure version possible for filtering sparkling wine or carbonated wines. In this case, filtration occurs at the pressure level of the champagne tank.
Crossflow filtration is also called tangential flow filtration. In this process, the medium to be filtered is forced under pressure through precisely defined pores of a membrane. A high overflow velocity in the module, however, prevents the pores from clogging by keeping the solids in suspension. The size of the pores determines whether microfiltration or ultrafiltration is used. During the filtration process, the concentration of retained solids within the system increases, which can lead to clogging or blocking of the membrane in various types of membranes. Blocking or clogging also occurs when a gel layer (colloids) is formed.
A centrifugal pump ensures a constant flow in the cycle through the hollow fibers and generates the required filtration pressure within these fibers. Unfiltrate is automatically fed into the cycle, corresponding to the filtrate discharge, while a small amount of retentate is also continuously discharged from the cycle and returned to the storage tank. As a result, the proportion of solids in the storage tank becomes more and more concentrated. Continuous backwashing of the hollow fiber modules keeps the filtrate performance at a constant level.
