Project background

In a paper mill the allowed chloride concentration in the process water was regularly exceeded. Due to the persistently high chloride load, there was a risk of corrosion damage to the paper machine.

Goal and challange

The plant was designed to achieve a permanent reduction of the chloride load to below 50 mg/l. This was possible despite strongly fluctuating inlet qualities of the sand filtered river water and a high biofouling potential.

Concept and realisation

Reverse osmosis was provided for the filtration of the river water pre-filtered on site by a gravel filter. To ensure a stable operation and a long lifetime of the membrane, special low-fouling membranes were selected. In addition, the plant was equipped with a special OSMO cleaning system (CIP), which enables the separate cleaning of highly stressed plant components (single bank rinsing)..

Advantage for customer

• A permanent and safe supply of process water to the paper mill while reliably complying with all limit values
• Savings in operating costs due to minimization of required process chemicals and reduced specific water consumption
• Increase of the "runnability" of the paper machine through higher process water quality
• Improvement of the product quality

Facts and figures