Improved removal of sticky and light contaminants from wastepaper. Final report, April 1, 1995--December 31, 1997

Work under this two-year cooperative agreement addresses improved removal of light and sticky contaminants from waste paper. Such contaminants occur in ever-increasing amounts, resulting from glues, labels, book bindings, packaging tapes, etc., all associated with the waste paper stream. Despite various cleaning steps in the paper mill recycling systems, residual contamination remains, causing big problems with the product quality and with paper machine and converting operations. Some grades cannot be recycled at all. Stickies are truly a barrier against increased paper recycling. The stickies problem was attacked in four project segments--three of those have yielded tangible results. One segment has been outstanding in its success; namely, the development of a centrifugal reverse cleaning system consisting of primary and secondary stages, which have unparalleled high efficiency in the removal of light and sticky contaminants. This cleaning system, consists of primary XTREME and secondary XX-Clone units. Another segment of this work, washing wax contaminated old corrugated wastepaper (OCC), also has resulted in the new Xtrax process which was released for sale