Fiberline Optimization through Implementation of Advance Process Control Utilizing Innovative Sensor Technology

摘要

Fiberline process is all about selective lignin removal and hence kappa number indicating residual lignin concentration is the most important process measurement. Traditional fiberline unit operations process control has been based on lab measured kappa which in the recent past has been replaced by multi-point kappa analyzers. These complicated systems suffer from many deficiencies, such as slow signal update and offer very high total cost of ownership. An oftentimes equally important but neglected component is the dissolved (or filtrate) lignin moving through the process, which also can widely vary and consume a significant portion of bleaching chemicals. Inaccurate measurement of dissolved lignin will lead to overuse of bleaching chemicals and increased costs to the operation. With these critical measurements being problematic, new innovative technologies have been developed to enhance the ability to optimize the pulping process and deliver significant sustainable gains in business performance for the pulp industry. These sensors can accurately measure lignin concentrations in various forms, including fiber kappa and filtrate kappa, allowing pulp mill operators to fine tune the process by taking firm corrective actions and reduce variability. This paper will discuss in-depth unit operations process control strategies utilizing the recently developed process measurements including fiber and filtrate lignin and its impact on economics fiber line operations.