The Effect Of Pulping Technology On The Shive Content Of Chemimechanical Pulp From Aspen

Paper industry vigorously develops and all kinds of pulping processes are developed presently. The chemimechanical pulping is a very important method nowadays. The shive content has been a tough problem in the papermaking process, the excessive shive content will not only bring the disturbance to the papermaking process, but also affect the paper quality. Because the existence of shive can cause many paper sickness, like scratch in blade coating, light spot, fish eye, etc.and these factors will limit the application of chemimechanical pulping, the problem of shive content is especially important in chemimechanical pulping.In order to solve this problem, the effects of the pulping technology on the shive from chemimechanical pulping were analyzed. The effects of the pulping technology of CTMP and the chemical doses used in the pretreatment of APMP on the shive content are discussed. Aspen is used in this research.The refining energy consumption is also an important parameter.The studies showed that, in the pretreatment of aspen CTMP, the shive content decreases as the chemical doses of NaOH increase under the same refining energy consumption. The effects of the chemical doses of Na₂SO₃ on the shive content are not a bit at 90℃. But the shive content decreases as the chemical doses of Na₂SO₃ increase under the same refining energy consumption and the efficiency of refining is even higher as the temperature is raised to 120℃.The results showed that, in the refining technology of CTMP, the shive content decreases as the refining consistency increases. The shive content and the refining energy consumption are only a little as the refining consistency is low, but the pulp properties are not good. 20% refining consistency is excellent. The shive content decreases as the narrow refining gap decreases under the same refining times, The shive content decreases as the refining times are increased under the same narrow refining gap. The shive content is almost the same under the narrow gap of 0.10mm as 0.05mm when the refining times are same. The effects of the refining pressure on the shive content are obvious. The shive content and the refining energy consumption decrease as the refining pressure increases. And it is the most obvious as the refining pressure rises to 152r.min^-1.The results showed that, in the pretreatment of aspen APMP, the shive content and the refining energy consumption decrease as the chemical doses of NaOH increase. And it is more obvious in the first setp of pretreatment than the second. The chemical doses of H₂O₂ will not affect the shive content and the refining energy consumption.