International technology Group ANDRITZ has successfully started up the pulp line delivered to JSC Arkhangelsk Pulp and Paper Mill (APPM) at the Novodvinsk mill, Russia. The new line features ANDRITZ green liquor technology for efficient pulp cooking, refining, and washing and produces 1,000 t/day of semi-chemical pulp for the production of corrugated board from birch and aspen.
Semi-chemical pulp is produced in a combination of mild chemical treatment and subsequent mechanical treatment in which the fibers are liberated from the wood matrix. This delignification process step is interrupted at an early stage in order to increase the yield and produce stiff fibers – an important quality criterion in the production of corrugated medium. A major advantage of the ANDRITZ green liquor technology, which is mainly applied for hardwoods and enhances the fiber quality substantially, is the efficient and easy recovery of cooking chemicals in the adjacent kraft mill. Thus, no additional process steps are needed for chemical recovery.
With this new line, the production capacity of APPM has doubled, while productions costs and waste water volume have been substantially reduced.