摘要 目前,我国轻型纸原料主要以进口商品针叶BCTMP或自制阔叶BCTMP、APMP 为主,适当配用漂白针叶化学浆。以高得率浆来保证轻型纸的高松厚度和不透明度,以 化学浆来适当提高纸页结合强度。当前在轻型纸抄造工艺、设备、助剂水平均与国际先 进水平存在差距的前提下,再由于原料配比的原因,不同程度地存在由于进口商品针叶 BCTMP造成的原料成本高,或由于国产阔叶BCTMP、APMP纤维平均长度小造成的不 同角度的产品质量差问题。 本研究针对当前我国轻型纸生产原料所带来的问题,基于国产杨木BECMP(挤压法漂 白化机浆)的纸浆强度高、能耗小等优势,试图以国产杨木BECMP为主要原料,充分 发挥该浆种制浆得率高、成浆强度好、制浆成本低的优势,探讨在尽可能少配用漂白化 学浆的条件下,制备高品质轻型纸的可行性;与此同时,对制备过程中浆料配比、打浆 度、填料加入量及方式、施胶方式等主要生产工艺条件进行优化,为杨木BECMP生产 轻型纸的工业化推广奠定理论基础。 研究结果表明,选定针叶浆与阔叶浆的配比、针叶浆打浆度和阔叶浆打浆度为正交 实验的三个因素,运用L9(33)正交表进行分析实验,通过直观分析、极差分析、方差分 析以及趋势曲线分析相结合的综合分析方法,得出有利于纸张抗张指数的最佳组合,即 为漂白针叶化学浆与漂白阔叶化学浆比例为3:1,漂白针叶化学浆的最佳打浆度为5557 °SR,阔叶化学浆最佳打浆度为3235 °SR。 对杨木BECMP分别配以针叶化学浆和阔叶化学浆所抄纸张的性能检测,检测结果 显示,当杨木BECMP的用量<84%时,均可得到稳定的较为理想的纸张强度;经过进 一步的优化实验分析,确定在实验室条件下的纯纤维体系巾使用杨木BECMP抄造轻型 纸具有可行性,且原浆的最佳抄造条件为84%杨木BECMP: 12%商品漂白针叶化学浆:4% 商品漂白阔叶化学浆。 以上述纯纤维体系中所得抄造条件为前提,根据轻型纸的质量特点和要求,采取中 性施胶的方式。由于中碱性施胶剂AKD具有操作简单、易于控制、不易结垢等优势, 故选用AKD作为杨木BECMP抄造轻型纸的施胶剂。施胶实验的预实验结果显示,施 胶过程基木不会造成轻型纸松厚度的变化,并且当使用轻施胶方式时不会对轻型纸抗张 强度产生不良影响,但当施胶剂用量超过0.25%时会造成抗张强度明显下降。因此,优 化实验结果表明,当AKD的添加量在0.18%0.22%之间时,可以得到较好的施胶度, 并对纸张的抗张强度有所增加,同时不会使松厚度有明显的下降变化。 在对填料与助剂进行选择时,考虑到中碱性AKD施胶,填料选择沉淀碳酸钙 (PCC)。依据PCC具有较小的密度与粒度,并有较高的折射率和光散射系数、白度与 不透明度高的物理特件,应用PCC抄造轻型纸可以满足轻型纸对松厚度和不透明度的 要求并且能够增强纸张印刷适性。实验得出,当沉淀碳酸钙的用量为15%20%时,所 摘要 抄造的纸贞的松厚度、强度与施胶度均没有较大幅度的改变,能够在较好地保持强度的 同时提高松厚度。 为了解决由于化机浆的细小纤维含量高和加入PCC填料对系统留着率的影响,本 研究采用CS/CPAM双元助留体系以提高纤维的留着率增强AKD的施胶效果,用量为 1.0%/200ppm。通过验证实验的检验,采用本工艺抄造轻型纸的可靠性较好,所抄造的 手抄片的平均物理指标为:松厚度2.44cm3/g,抗张指数41.60Nm/g,不透明度90.6%, 施胶度161.68s。 本研究的完成,能够有效地节约轻型纸的生产成本,提高轻型纸的物理指标,为我 国优质轻型纸的生产提供一条新思路,使我国轻型纸生产行业的水平得到一定的提升; 拓展了杨木BECMP的应用范围,同时也为挤压法制浆技术的推广奠定理论基础。 关键词杨木BECMP;轻型纸;配比;AKD; PCC Abstract Abstract Recently, domestic low density printing paper was made with inward commercial Softwood BTCMP or commercial Hardwood BCTMP and APMP as the main material, adding bleached softwood chemical pulp in a ratio. The effect of HYP assure the high bulk and opacity, the effect of Softwood enhance the bonding strength. Compared with international level, our nation low density printing paper had some gaps at technology, equipment and addition agent. On this condition, as the reason of ratio of raw materials, there was being high cost in different degrees due to the high price of inward commercial Softwood BTCMP. Or there was poor product quality in due to the short fiber length of domestic Hardwood BCTMP and APMP. The questions were brought by the product materials, on the basis of some advantages of domestic aspen BECMP(bleached extrude chemical pulp), such as high pulp strength,low power consumption and etc. The study tried to discuss the feasibility of making low density printing paper on basis of adding bleached chemical pulp as little as possible. And then, optimize the ratio, beating degree, the dosage of fillings and the adding mode, sizing mode and so on. The study laid a theoretical foundation in order to popularize the industrialization of making low density printing paper by using aspen BECMP. The result indicated, the study used orthogonal tableL9(3J) to do experimental analysis (three variables were ratio of SW pulp and HW pulp, beating degree of SW pulp, beating degree of HW pulp respectively). Combining intuitive analysis, range analysis, variance analysis and trend curve analysis, obtained the optimum combination which was benefit for tensile index. The data of this optimum combination was that the ratio of SW pulp and HW pulp was 3:1, the beating degree of SW pulp was 55570SR,the beating degree of HW pulp was 3235°SR. The sheet which was using aspen BECMP with SW pulp and HW pulp respectively was needed to do performance test. The result of performance test indicated, when the dosage of aspen BECMP was below or equal to 84%, the tensile index was steady and ideal. Through the further optimum experimental analysis, have ensured the feasibility of making low density printing paper with aspen BECMP under the lab in the pure fiber system. Moreover, the optimal condition was 84% aspen BECMP: 12% commercial bleached SW chemi-pulp: 4% commercial bleached HW chemi-pulp. According to characteristic and requirement of low density printing paper, these conditions as premise, the study took neutral sizing mode. Due to neutral sizing agent AKD had some advantages, such as simple operation, easy control, low scaling etc. So the study had chose AKD as sizing agent for making low density printing paper with aspen BECMP. -ill- Abstract According to pre-experiment result, sizing process affected slightly bulk of low density printing paper, and,light sizing didn't produce harmful effect for tensile strength, only when the dosage of sizing agent exceeded 0.25%,tensile index declined obviously. Therefore, the result of optimum experiment indicated, when the dosage of AKD was 0.18%0.22%,sizing degree was excellent and tensile index increased, at the same time, bulk didn’ t decline obviously. Consider with neutral-alkaline sizing agent(AKD), filler was chosen PCC(Precipitated Calcium Carbonate). According to low density and particle size, high refractive index and light scattering coefficient, high brightness and opacity of PCC, using PCC to make low density printing paper could meet the requirements of bulk and opacity and could enhance printability. Experiment obtained, when the dosage of PCC was 15%^20%, the bulk , strength and sizing degree of sheet hadn't a great change, and could raise a certain bulk meanwhile preserved strength. In order to solve filler retention rate of the system which was affected by high content of fines and adding PCC, this study used CS/CPAM dual retention aid system to improve filler retention rate of fiber in order to enhance sizing efficiency, the amount was 1.0%/200ppm. Reliability of this process was well by verification test, mean physical indexes of handsheet were as followed: bulk was 2.44cm3/g,tensile index was 41.60Nm/g, opacity was 90.6%sizing degree was 161.68s. Completion of this article would save cost of producing low density printing paper effectively, improve the physical index of low density printing paper, provide a new thought for high-grade low density printing paper' production, promote the level of low density printing paper industry in china. At the same time, expand application range of aspen BECMP and also lay a theoretical foundation for popularizing extrusion pulping technology. Keywords aspen BECMP; low density printing paper; ratio; AKD; PCC -IV- hi朵 目录目录 mw i Abstract Ill 1舰 i 1.1 EJI 5 1 1.1.1国际制浆造纸工业的发展现状 1 1.1.2国内制浆造纸工业的发展现状 2 1.2高得率制浆技术 3 1.2.1高得率浆需求背景 3 1.2.2高得率制浆简介 3 1.2.3高得率制浆在我国的发展 4 1.3 BECMP制浆技术的发展与应用 4 1.3.1 BECMP制浆技术简介 4 1.3.2制浆原理 5 1.3.3杨木BECMP生产流程 6 1.3.4BECMP制浆特点 7 1.3.5 BECMP制浆技术应用现状 7 1.4轻型纸的现状和发展 7 1.4.1轻型纸简介 7 1.4.2国外轻型纸现状 8 1.4.3国内轻型纸现状 8 1.4.4国内外轻型纸的比较 10 1.4.5轻型纸的发展趋势 11 1.5本研究的目的和意义 11 2杨木BECMP配抄轻型纸浆料配比研究 12 2.1实验材料 12 2.2实验主要仪器 12 2.3实验条件及参照标准 12 2.4实验方法 12 2.4.1实验方法 12 2.4.2轻型纸参照标准 12 2.5结果与讨论 13 2.5.1浆料成浆特性分析 13 2.5.2正交实验分析 14 -V- H采 2.5.3杨木BECMP比例分析 16 2.5.4配比优化实验 17 2.6木章小结 17 3施胶剂的应用分析 18 3.1施胶剂的简介 18 3.2实验材料 19 3.3实验原理 19 3.3.1 AKD的施胶机理及特点 19 3.3.2 AKD的添加量 19 3.4实验设备及方法 20 3.5实验步骤 ° 20 3.6结果与讨论 20 3.6.1 AKD 的特性 20 3.6.2预施胶实验结果 20 3.6.3优化AKD的添加量 21 3.7本章小结 22 4填料、助剂的应用分析 23 4.1填料、助剂的选择 23 4.1.1填料的应用性能 23 4.1.2填料的种类 23 4.1.3填料的选择 24 4.1.4助剂的选择与用量 24 4.2实验材料 25 4.3实验设备及方法 25 4.4实验步骤 25 4.5结果与讨论 25 4.5.1填料用量讨论 25 4.5.2助剂体系用量讨论 26 4.6木章小结 27 5主要工艺优化验证 28 5.1实验材料 28 5.2实验设备及方法 28 5.3实验步骤 28 5.4验证实验结果分析 28 5.4.1验证实验结果 28 5.4.2主要指标数理分析 29 -VI- tis 5.4.3总物理指标 29 5.5使用杨木BECMP抄造轻型纸的优势分析 29 5.6本章小结 30 结论