On-line chemical analysis of pulp and calcination processes

Purpose and goal

The purpose of this feasibility study was to, through lab and field tests, investigate the possibilities of the LIBS-technique to continuously detect undesirable metal elements in two mass processes (dissolving pulp and lime mud). Further, the usability and benefit of the LIBS-technique for the two processes were investigated. A plan for a coming RoD-project was written that aims toward an industrial implementation of the LIBS-technique.

Expected results and effects

The LIBS-technique was able to detect the undesired elements in the material in the processes. As the number of samples were few, the accuracy in element quantity could not be estimated. Nevertheless, the conclusion is that the LIBS-technique can be used for on-line detection of undesirable elements in dissolving mass and mesa and provide information to control the production process. This process control will open possibilities for improved quality and a more stable process with less downtime.

Planned approach and implementation

Initially the quantities of the different undesirable elements were compiled for the two processes (dissolving pulp and mesa). Then lab measurements were made on collected samples from the two processes, and field measurements were made on the lime mud filter at Mörrums Bruk. The usability and benefit of the LIBS-technique were analysed and summarized. Finally, a plan for a coming RoD-project was written.