Industrial scale-up of fiber recovery technology from mixed office waste fine screen rejects

Abstract

Industrial-scale testing was performed for fine screen reject recovery technology with a mixed office waste (MOW) pulping line. Results showed that the recovery system removed macrostickies and dirt specks with an efficiency of 95.7% to 98.3% and 51.5% to 76.8%, respectively. These results were not affected by the running consistency (0.26% to 1.44%). The recovery system improved the physical strength of the pulp. Relative to untreated rejects, the tensile index increased 5.1% to 15.2%, the tear index increased 6.6% to 11.4%, and the breaking index increased 6.6% to 25.7%. Running consistency had no obvious effects on tensile strength and tear strength, but bursting strength increased with increasing running consistency (%). The volume energy consumption (y) increased with increasing running consistency (x), and a linear relationship of y = 0.73x + 4.2191 (R² = 0.9466) was observed. The specific energy consumption (y) of the pulp decreased with increasing running consistency (x), and the relationship could be expressed as y = 499.67x-0.906 (R² = 0.9959).