ANDRITZ pulp washing solutions
From brown stock to bleaching, washing plays an essential role in maintaining pulp quality throughout the fiberline. ANDRITZ provides washing solutions that not only result in high quality pulp, but are also efficient and environmentally friendly.
Pulp washers are essential to fiberline performance as the pulp needs to be washed at almost all stages of the process. The washing result at one stage affects all the subsequent stages. Therefore, the choice of washers has to be just right.
Whether you are building a greenfield mill or upgrading an existing line, ANDRITZ can assist with washing solutions that result in high-quality pulp, achieved in an efficient, environmentally friendly way.
Processes and technologies available from ANDRITZ
Drum displacer washer
The ability of the ANDRITZ drum displacer (DD) washer to incorporate from one to four displacement washing stages in a single unit, greatly simplifies fiberline layout. Innovative connection of filtrates reduces the amount of chemicals required in the oxygen delignification and bleaching stages and lowers heat and water consumption – reducing operating costs and minimizing effluents. Recent enhancements in the washer’s flow hydraulics are the increasing washing efficiency and washer capacity, resulting in capacities of over 5,000 admt/d.
GasFree filter vacuum drum washer
The ANDRITZ GasFree filter is an advanced vacuum drum filter washer. Usually installed in retrofit cases, it can be used to complement the washing process in special cases when only one stage of washing is required and the washing stage temperatures are not high. GasFree filters can be used for brown stock, post-oxygen delignification, and bleach plant washing.
The ANDRITZ Pressure diffuser is a diffusion-type washer. Today, most diffuser systems are installed in retrofit cases, where they can be used in brownstock washing in the blowline.