Compatibility of pressure sensitive adhesives with recycling unit operations

Abstract

Removal of pressure sensitive adhesives (PSAs) from recovered paper is a major problem facing the paper recycling industry. As a result of a United States Postal Service (USPS) initiative, which currently purchases about 12% of domestic PSA production, a team was formed consisting of representatives from the USPS, the Forest Products Laboratory, Springborn Testing and Research, paper recovery companies, paper recyclers, adhesive manufacturers, and chemical suppliers. This large team of cooperators has the common goal of formulating PSAs that can be efficiently removed during the fiber screening operations. To evaluate new PSAs, an initial pilotscale separation sequence and an operating protocol were developed. This fiber sequence involved high-consistency pulping, pressure screening, forward cleaning, reverse cleaning, flotation and washing. The sampling protocol allowed the evaluation of the PSA removal efficiency of each of the unit operations, An initial trial of 14 adhesives has been completed. These data indicate that some PSA formulations can be easily removed during fiber screening, but others are only poorly removed.

Citation

Bormett, David.; Houtman, Carl.; Abubakr, Said.; Peng, Joseph. 1999. Compatibility of pressure sensitive adhesives with recycling unit operations. Fundamental advances and innovations in the pulp and paper industry. New York : American Institute of Chemical Engineers, 1999. AIChE symposium series ; no. 322.:p. 159-164.