The avoidance of deposits in the felt is an important prerequisite for its good function during the entire running time. If inorganic and/or organic impurities from the process water deposit on the felt, its ability to absorb water diminishes over time. Furthermore, continuous mechanical stress causes the felt to compact, which also affects water absorbency.
By continuously adding CO2 to the high-pressure spray water, the tendency to form inorganic deposits is reduced. An “overdose of CO2" can even lead to the dissolution of existing deposits in the felt. Through the loss of pressure after the spray nozzle, the CO2 can outgas and support the restoration of the original felt volume. In both cases, the result is better water absorption by the felt.
- Better and more constant permeation over the felt running time
- Drying section has lower energy requirements
- Savings in acidic cleaning materials
- When required, a simple check of the CO2 amounts used is possible
This technology has been patented by us.
As hardware for adding and dissolving the carbon dioxide under the high back pressure in the spray water line we prefer the Clapet nozzles developed by Messer.