Quantification of macro stickies and optimization of the wastepaper deinking process - A method applied to a Bowater mill decreased stickies by 38%

The control of macro stickies at Bowater Pulp and Paper Canada is discussed. A method has been developed as a quality control measure for deinking operation. A Sommerville six-cut screen uas used to concentrate macro stickies in screen rejects followed by quantification by image analysis. Trials carried out with mill's pulp samples showed that the method has a good reproducibility. The methodology was used to optimize fine screens and Gyrocleaners. Process optimizations decreased the over-all macro stickies level in the deinked pulp hy more than 38%.