Removal of Stickies in a Recycle Newsprint Mill Using the Gyroclean, 1997 Recycling Symposium Proceedings

The efficiency of removing primary (insoluble) stickies from a 70/30 news/mag furnish using 2 parallel Gyrocleans is reported. The investigation was done at the ANM Albury mill, Australia, during normal operation. Operating variables investigated covered flow rates from 155 to 180 l/s (2600 to 3000 gpm), pressure drop levels from 120 to 240kPa (17 to 35psi) and mass reject rate levels from 1 to 4%. Feed consistency was held constant at 1.05%. Stickies counts were determined by the number of stickies particles retained on a 150 micron slotted screen.

From the study it was found that removal of insoluble stickies varied from between 10 and 58% per Gyroclean pass. Removal efficiency generally decreased with increased unit pressure drop, at the same volumetric flow rate, and increased with increasing accept ressure or mass rejects rate. Energy consumption levels were relatively high with the feed pump motor and Gyroclean rotating motors having a combined power demand of 173kW for a through put of 150 tonnes per day on 50 percent recirculation.