As a result of a United states Postal Service initiative, a work team consisting of the USPS, the Forest products Laboratory, Springborn Testing and Research, and industry representatives was formed. The industry representatives include papermakers, paper recyclers, paper collectors, equimpent manufacturers, paper users, nad sadhesive and chemical suppliers. The objective of the work team is to develop new and innovative solutions to the problems associated with recycling recovered paper containing pressure-sensitive adhesives. Initial oopen discussions were held at USPS-sponsored conferences during 1995-1997, followed by work team meetings, also organized by the USPS. As a result of this collaboration and based on the criteria set by the paper industry, the adhesive industry is formulating new PSAs that are mostly removable in the screenign stage of the recycling process. As a result of these combined efforts, protocols were developed to evaluate the newly developed adhesives. This paper outlines a pilot-scale separation sequence to assess the removal of contamminants from the feed stock containing PSAs. The sequence involves high consistency pulping, pressure screening, forward and reverse cleaning, and washing and flotation deinking.
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