Novel Concepts for Monitoring and Control of Deposits in the Pulp and Paper Mills

Deposit control programs in pulp and paper mills are critical for machine runnability and paper quality. Although these programs are used in most systems, the management of their performance has historically been quite poor and complicated, entailing intensive analytical work and representing, in general, a reactive approach to the problem. This paper introduces the use of online and offline monitoring tools to enable a proactive approach to deposit control. Monitoring techniques are used for program dose optimization, trial evaluation and for studying the effect of process conditions on the deposit propensity of the media. Nalco's innovation integrates online monitoring technologies with deposit control programs to monitor and control microbiological slime, pitch and stickies, and inorganic scale. With demonstrated success in the laboratory and at the mill sites, this approach enables papermakers to optimize chemical usage, ensure deposit control program performance, improve operating efficiency and ultimately reduce total cost of operation.