Deinking selectivity (Z-factor) : a new parameter to evaluate the performance of flotation deinking process

Abstract

Reducing fiber loss is also important to conserve resources and reduce the cost of secondary fibers. This study proposes a deinking selectivity concept that considers both ink removal and fiber yield in determining the performance of deinking operations. The defined deinking selectivity, or Z-factor, is expressed by the ratio of ink removal expressed by the International Standards Organization (ISO) brightness gain or the reduction in relative effective residual ink concentration (ERIC) and the relative fiber rejection loss. Pilot-scale flotation deinking experiments showed that Z-factor weighted brightness gain and ERIC reduction are good indicators of deinking process efficiency. The Z-factors are good indicators of the efficiency of a deinking stage or process. A simple criterion developed using the stage Z-factor was applied to a mill operation to determine the stage economics.

Citation

Zhu, J.Y.; Tan, F.; Scallon, K.L.; Zhao, Y.; Deng, Y. 2004. Deinking selectivity (Z-factor) : a new parameter to evaluate the performance of flotation deinking process. 7th Research Forum on Recycling, September 27-29, 2004, Quebec City, QC, Canada [electronic resource]. [Montreal : PAPTAC, 2004?]: p. 109-113.