Environmentally sound alternatives for upgrading mixed office waste

Mixed office waste paper is a source of high quality fiber that could be reclaimed for use in printing and writing grade paper, However, conventional deinking and bleaching technologies do not effectively remove laser and xerographic toner inks or paper dyes. Residual ink specks and color limit the products in which deinked pulp can be used. Complementary alternatives, enzyme deinking and fiber loading, have been developed at the Forest Products Laboratory to upgrade mixed office waste paper. These new processes are environmentally compatible, affordable, and use equipment typically available in deinking mills. This paper reports the benefits of combining these two green technologies to meet the challenge of upgrading low-value mixed office waste. Benefits of enzyme deinking include effective toner removal, improved effluent quality, increased pulp drainage, cost effectiveness, and decreased electrical energy consumption. Benefits of fiber loading include utilization of waste carbon dioxide from stack gases, extended fiber resource by filler substitution, minimized sludge, and masked residual ink and contaminants.