双螺杆预浸渍磨浆机制浆性能研究

Research on performance of chemical mechanical pulping with twin-screw preimpregnating refiner

选取苏北地区不同品质的杨木加工剩余物为原料,采用一种我国自主研发出来的新型预浸磨浆系统以及常规的高浓盘磨对比研究不同品质杨木加工剩余物对化学机械法制浆性能的影响。研究结果表明:杨木加工剩余物的质量对制取化机浆的制浆得率、磨浆能耗、纸浆白度及纸浆的强度性能均有不同程度的影响。在相同H2O2用量为7.0%,NaOH用量6.0%条件下,以品质较好的杨木加工剩余物为原料,采用双螺杆新型预浸磨浆系统制得化机浆的得率可达85.6%左右,纸浆白度值81%ISO以上,在游离度为300mlCSF条件下,抗张强度可达到33N.m/g以上;以品质较差的杨木加工剩余物为原料,制浆得率为84.2%,纸浆白度为73%左右,抗张强度为29N.m/g。另外,采用双螺杆新型预浸磨浆系统比采用高浓盘磨制浆磨浆电耗上可节省30%左右,制浆得率、纸浆白度及纸浆的强度性能差异不大。

The effect on chemi-mechanical pulping performance was studied with twin-screw preimpregnating refiner and disc refiner, using poplar wood processing residues from the northern of Jiangsu province as raw material. The results show that the quality of poplar wood processing residues has an impact on pulping yield, specific refining energy, pulp brightness and strength properties. Under the chemical conditions of hydrogen peroxide dosages of 7.0%, combined with 6.0% sodium hydroxide based on oven dry chip, for impregnation, the high quality pulp with brightness levels of 81%ISO or up and the yield of about 85.6% is obtained by twin-screw refiner preimpregnating using high quality poplar wood processing residues. At the freeness level of CSF 300ml, pulp tensile strength can reach to 33N.m/g or up; by using poor quality poplar wood processing residues as raw material, the pulping yield reaches to 84.2%, brightness up to about 73%ISO, tensile index 29N.m/g. Furthermore, 30% specific refining energy can be saved with twin-screw preimpregnating refiner followed by high concentration disc refiner, while the yield of pulping, pulp brightness and pulp strength have only a little difference.