Recaust

Recausticizing recovers the costly alkaline chemicals used for in cooking process of a mill. Green liquor (sodium carbonate) is converted to white or cooking liquor (sodium hydroxide) through lime addition. Minimizing variability in the recausticizing process is crucial to ensure consistent cooking of the woodchips in the pulping process. Typical operational challenges include filter scaling, slaker boiling over, and over liming.
Spartan’s solutions are tailored to meet challenges in this demanding environment and allow effective operation of the recausticizing. Highly accurate Rosemount instruments are used to measure key process variables including flow, temperature, density, and conductivity. Fisher control valves are used to control flow while minimizing the effect of scaling and erosion. The predictive modeling and advanced tuning functionalities in DeltaV allow operators to control and optimize the process by maximizing causticizing efficiency while maintaining consistent white liquor quality.