Customer case:

Visy Tumut exceeds targets by optimizing causticization

Feb 21, 2020

Visy’s kraft mill in Tumut wants to optimize the asset performance, increase production, and ensure process competitiveness with the latest technology. With causticizing optimization, their expectations and return on investment (ROI) targets have been exceeded.

Visy Tumut kraft mill uses Valmet's advanced process controls to optimize causticizing
After a few months’ use of Valmet APC with Valmet Recovery Liquor Analyzer, the results exceeded our targets. Overliming has been eliminated, TTA control has improved significantly, lime kiln is more stable, digester uses less white liquor/steam and production capacity increases.
Jaco Oliver, Operations Engineer, Visy Tumut


Location Visy Tumut kraft mill, Australia
Customer challenge Optimize the performance of the process and ensure process competitiveness with the latest technology. More specifically, the mill wanted to reduce energy and chemical costs, eliminate production constraints, optimize control and eliminate process variations, and improve return on investment (ROI).

Valmet Recovery Liquor Analyzer (Valmet Alkali R)

Valmet Advanced Process Control (Valmet APC) 

Valmet Causticizing Optimizer


ROI exceeds targets

Increased production (870 ADT more paper in 40 days) 

Energy efficiency:

  • Steam saved 56 t/d

Chemical efficiency:

  • No make-up CaO purchased since the control has started – buying CaCO3 instead

Production capacity: 

  • Improved CE% stability, higher and more stable TTA
  • White Liquor flow reduced by 11,5%
  • Extraction liquor to evaporation dropped by 3,65%
  • Significantly reduced slaker and causticizing vessel scaling
  • No overliming since control start-up
Keywords Pulping and fiber, Asia Pacific, Automation