ANDRITZ Receives Order for Disc Filter Rebuild

International technology group ANDRITZ has received an order from SCA (Svenska Cellulosa Aktiebolaget) to rebuild a disc filter at their pulp mill in Ortviken, Sundsvall, Sweden.

After the rebuild, the production capacity of the disc filter (originally supplied by ANDRITZ) will be tripled to 900 bdmt/d, and the filtrate flow will be increased to a maximum of 130,000 l/min. The refurbished disc filter will ensure the requested throughput at different beating degree levels, ranging from 300 to 700 CSF, for the production of various high-quality pulp grades. Start-up is scheduled for the fourth quarter 2022.

The ANDRITZ scope of supply comprises the main disc filter components, such as:

  • New hollow shaft with high-volume filtrate channels – the largest-volume filtrate channels ever designed for an ANDRITZ disc filter
  • 396 ANDRITZ SuperFlow sectors for 22 filter discs with customized filter bags
  • State-of-the art disc guiding system
  • New filtrate valve with automated adjustment to the different beating degrees
  • New knock-off and cleaning shower systems
  • New repulper screw
  • On-site services for installation and start-up as well as supervision of start-up

ANDRITZ has developed a new filter bag solution able to handle beating degrees above 600 CSF. The new development was tested on a full-size disc filter during a 3-day trial at the ANDRITZ pilot plant in Graz, Austria. This was the first time that a single disc filter could be operated at such a wide CSF range.

The disc filter rebuild order is part of SCA’s ongoing project to transform the existing TMP (thermo-mechanical pulp) line at the Ortviken site into a CTMP (chemo-thermo-mechanical pulp) plant with an annual capacity of 300,000 tons per year.