Bleaching chemicals often represent the second largest cost in chemical pulping. With a known operational issue of over usage of bleaching chemicals to ensure final stage pulp brightness, plant owners report annual savings of USD 1.5 million/year from bleach plant optimization alone.
With the regulatory control loops in place, it is often expected of operators to manually tune the addition of bleaching chemicals to satisfy the final brightness at a reduced cost. Given that the bleaching process comprises multiple interacting units, with a multitude of material and process disturbances, and dynamically changing, it is mostly impossible for operators to rely on past experiences to decide on optimal setpoints.
SentianController would optimize chemical usage for a given final brightness with respect to dynamic models designed to adapt to changing process disturbances. The models predict the effect of chemical load, pulp quality, and operating condition on downstream kappa number and brightness throughout the fiberline, and compute the optimal dose setpoints for each operation unit. Recommended setpoints can be presented to operators as suggestions or automatically applied to the process.