Mechanical Pulping The Szego Mill has been used to refine thermally and chemically softened wood chips and thermally treated hemp into mechanical pulp for papermaking. Paper quality is good and energy consumption is lower than for disk refiners. Szego Mill pulp properties Freeness (mL) Avg fibre length (mm) Hemp 125 – 638 0.85 – 1.28 Black spruce 130 – 619 0.67 – 1.16 Properties of paper made with Szego Mill pulp Density (kg/m3)Tear Index (mN-m2/g)Paper from hemp and kraft pulp 247 – 592 3.21 – 8.23Paper from black spruce pulp 375 – 575 3.93 – 6.55