木片筛余物高得率半化学法清洁制浆技术研究

Study on Clean Production Technology in High-yield Semi-chemical Pulping with Woodchip Rejects

以太阳纸业备料车间木片筛选碎料(筛余物)为原料,对其烧碱法半化学制浆的实验室工艺和生产试验进行了研究。结果表明,筛余物采用半化学法制浆可获得较高得率和环压强度的纸浆,且用碱量对纸浆性能有显著影响。相对8%NaOH(相对于绝干原料)化学预处理,采用14%NaOH化学预处理结合两段浆浓22%的高浓磨浆工艺,所制半化学浆抄造浆张的裂断长和环压指数分别达2.89 km和9.76 N·m/g,是前者的1.9倍和1.2倍,而且优于现用国内OCC废纸浆抄造浆张;生产试验得到的浆张性能指标与实验室相吻合,其中紧度和环压强度分别达到GB/T 13023—2008瓦楞芯(原)纸AA级和A级优等品要求。

Taking the woodchip rejects filled from the chip screening systems of a papermaking mill as the raw material,the lab-scale pro⁃cess and industrial process of caustic soda semi-chemical pulping were studied.The results showed that pulp with a high yield and ring crush strength was obtained via semi-chemical pulping from woodchip rejects,of which the properties were significantly affected by the alkaline dosage.The breaking length and ring crush index of the pulp pretreated with 14%NaOH followed by two-stage high-consistency refining pro⁃cess with paper concentration of 22%could reach 2.89 km and 9.76 N·m/g,respectively,which was 1.9 times and 1.2 times higher than that of the paper pretreated with 8%NaOH,and also better than the OCC paper used in the domestic mill at present.Furtherly,the indica⁃tors of the paper obtained in the industrial process were consistent with the laboratory.The tightness and ring crush strength of the prepared paper reached AA grade and A grade of corrugation medium in GB/T 13023-2008.