CHARACTERISTICS OF LIGNIN REACTIONS IN SODA COOKING OF WHEAT STRAW PART 1 REACTION OF UNCONDENSED LIGNIN

INTRODUCTIONWheatstrawisanimportantfiberrawmaterialinmanycountries熏particularlyinAsia熏EasternEurope熏andLatinAmerica熏whereareshortofwoodsuppliessuitableforthepurpose.Ithasbeenreportedthatnon-woodplantfiberswillplayanincreasingroleintheglobalpulpandpaperindustry熏andtheworldstrawproductionwasapproximately10熏000milliontonsin1998眼1演.ThelargestcapacityforproducingpulpfromthestrawisconcentratedinChina.IntheEuropeanCommunitythereisalsoagrowinginterestinthedevelopmentofnon-foodapplicati…     

越南甜竹蒸煮反应历程研究

以越南甜竹为对象,采用硫酸盐法蒸煮,研究越南甜竹蒸煮反应历程。结果表明,煮浆适宜工艺条件为：用碱量22 %,温度170 ℃,保温时间120 min,硫化度20 %,液比4∶1。蒸煮过程中木质素脱除可分为大量脱除、补充脱除和残余脱除木质素3个阶段。蒸煮终点,浆料的Kappa值较高,即甜竹比较难煮。     

低龄厚荚相思木的制浆造纸性能

对3年和6年生厚英相思,在各自的最佳硫酸盐法蒸煮工艺条件下,制取相近硬度的浆料,比较蒸煮、打浆、强度及漂白性能,进而对其制浆性能进行综合评价。     

IMPACT OF COOKING HOMOGENEITY ON PULP STRENGTH PROPERTIES

Cooking homogeneity of kraft pulping can have significant impact on pulp strength properties. We have studied cooking homogeneity of two kraft digesters within Stora Enso. One of the digesters is a one-vessel hydraulic continuous digester (digester A)and the other one is a two-vessel vapor/liquor phase continuous digester (digester B). They are located in the same mill and use the same softwood chip quality. Due to the differences in chip pre-steaming and cooking facilities and conditions, significant differences in pulp strength properties, reject contents and kappa variations have been found between the pulps produced in the two digesters. Digester A has a modem chip bin with efficient pre-heating and air removal, whereas digester B has poor chip pre-steaming conditions. Our strength delivery studies show that although the two digesters produce pulps with the same kappa number and viscosity, the pulp produced in digester A has about 20% higher strength delivery, l%-unit (based on wood) lower reject content and lower kappa variations based on FTIR spectra analysis on pulp sheet than the pulp produced in digester B.Results of the studies indicate that more homogeneous cooking, i.e., lower lignin/kappa variation in the fibers, leads to improved pulp strength properties. Efficient chip pre-steaming is important/essential for achieving homogeneous cooking. Rebuilding the equipment for improving chip pre-steaming conditions of digester B is to be carried out.     

意大利杨木制浆造纸性能的研究——硫酸盐-蒽醌法和烧碱-蒽醌法

<正> 目前,造纸原料已成为阻碍造纸工业发展的重要问题之一。这使得人们将注意力从针叶材逐渐转向阔叶材,转向速生杨树和桉树。在意大利杨木Ⅰ-214、Ⅰ-72、Ⅰ-63、Ⅰ-69的研究中,除Ⅰ-214得到有关国家的广泛引种和利用外,其他三种杨木作为造纸原料,仍处于试验阶段,而Ⅰ-214的利用在国外也仅限于制造机械浆和化学机械浆,化学浆的研究工作迄今尚无报道。我国从七十年代开始由国外引种了几种意大利杨,北京造纸所于一九七六年曾对最先引进的Ⅰ-214的制浆造纸性能进行了研究,证明Ⅰ-214杨为优良造纸用材,但对其他三种材种还缺乏系统深入的研究。 我们在对四种意大利杨的化学组成和纤维形态进行研究的基础上,着重进行了硫酸盐法、烧碱-蒽醌法、硫酸盐-蒽醌法和碱性亚硫酸盐法制取化学浆的试验研究,比较了四种速生杨木对制取化学浆的适应性。本文主要对烧碱-蒽醌法代替硫酸盐法的可能性和蒽醌在杨木硫酸盐法、烧碱法制浆中的作用以及四种意大利杨对碱法制浆的适应性进行了探讨。     

意大利杨木制浆造纸性能的研究——碱性亚硫酸钠-蒽醌法

<正>一、前言 碱性亚硫酸钠制浆方法使用氢氧化钠和亚硫酸钠为蒸煮液。其优点是:纸浆得率高,易漂白,纸浆的强度性能与硫酸盐浆相接近,并且不会产生硫酸盐蒸煮及回收系统所散发的恶臭硫化物,等等。因此,近年来国内外采用碱性亚硫酸钠制浆方法,对针阔叶木、芦竹、麦草等进行了一些试验研究。 碱性亚硫酸钠法蒸煮温度一般要比硫酸盐法高10—15℃,化学品用量也要高20％(或者蒸煮时间延长5倍)。最近发现,蒽醌在碱性亚硫酸钠法蒸煮中具有加速脱木素催化作用,因此,上述缺点可以通过添加蒽醌来弥补。 本试验以意大利杨木为原料,研究了碱性亚硫酸钠一蒽醌法制浆条件及其对浆质量和得率的影响规律。     

植物纤维复合胞间层的修复及纸页强度的提高

 研究了低卡伯值未漂硫酸盐阔叶木浆在过氧化物酶体系存在下,与松柏醇葡萄糖苷及果胶发生共聚反应,生成脱氢聚合物（DHP）及DHP-碳水化合物复合体,并利用¹³C-NMR分析了DHP-碳水化合物复合体的结构。结果表明：DHP-碳水化合物复合体中DHP结构单元之间主要通过β-O-4、α-O-4、β-β、β-5和β-1方式相连接,DHP结构单元还通过苯甲醚键、苯甲酯键和少量缩醛键与纸浆纤维和果胶相连。纤维胞间层经过修复后,纸张的强度有明显提高。纸张的干强度和湿强度分别提高37.5%和166.3%。木素前驱物可以与果胶及纸浆纤维中的多糖有效地发生共聚,使得纤维复合胞间层得到修复,因而提高纸张强度。     

RELATIVE IMPORTANCE OF WOOD DENSITY AND CARBOHYDRATE CONTENT ON PULPING YIELD AND PRODUCT QUALITY

INTRODUCTIONPulp quality depends on wood quality and pulping process conditions. Wood quality is a result of forestry management practices and a combination of genetic, physical, anatomical and chemical characteristics of the wood [35]. Eucalypt pulps are desired for printing and writing and for tissue paper grades due to their anatomical and chemical characteristics. It has been shown that wood density exerts significant influence on pulp quality [21]. This parameter, together with volum…     

ALKALINE PULP OF CORN STALKS

Pulping of corn stalks was studied in soda,soda-anthraquinone (AQ), kraft and kraft-AQ processes. The time, temperature and alkali concentration were varied in soda process. In respect to kappa number and pulp yield, 1 hour cooking at 1400C in 14% alkali were best conditions for corn stalks pulping. Pulp yield was increased by 5.5% and kappa number was reduced by 4.4 points with an addition of 0.05% AQ in the soda liquor. Breaking length was better in soda-AQ process than soda process but tear strength was inferior. In the kraft process, pulp yield was increased with increasing sulphidity and decreasing active alkali. The effectiveness of AQ in the low and high sulphidity kraft process was studied. Results showed that AQ was more effective in low sulphidity than high sulphidity. Strength properties in kraft processes were better than the soda and soda-AQ processes.     

桉本化机浆的傅里叶变换红外光谱分析

用傅里叶变换红外光谱法对桉木中各组分在碱性亚钠法化机浆预处理及漂白过程中的化学变化进行了研究。结果表明木材在处理过程中存在脱乙酰基作用；木素的烷基芳基醚键受到破坏；纸浆中纤维素的结晶度指数下降；随预处理时ＮａＯＨ用量的增加，本素中形成了新的共轭羰基和醌型结构，它们使纸浆白度下降。同时对不同纸浆在漂白过程中的变化进行了研究，对影响纸浆白度的因素进行了分析     

纸浆蒸球温度的计算机控制

阐述了纸浆蒸煮的计算机温度控制方法,对球内浆料温度的测量、控制中采用的数学模型和控制系统方案作了说明。并对手动操作与计算机控制的结果作了分析和比较。结果表明,对麦草浆的蒸球蒸煮采用计算机控制,可降低蒸解度的波动范围,提高粗浆和漂白浆得率以及蒸解度的合格率。     

ON THE BLACK LIQUOR AND RECYCLE COOKING OF AS-AQ STRAW PULP

1.INTRODUCTIONAs a kind of agriculture residues, straw occupies an important status in the non-wood papermaking material in China. Straw is herbaceous plant yearly, and composed with successive and organized cell groups that is similar with others plants. The construction of straw fiber has three obvious layers and the sequence is lamella, primary wall and second wall. Because the organization is loosen andporous, the lignin content is lower and the cooking liquor is easer to penetrate so…     

低纤维素酶活木聚糖酶对麦草浆的辅助漂白作用

利用低纤维素酶活木聚糖酶对麦草浆进行预处理,研究木聚糖酶在氯、碱、次氯酸盐(CEH)三段漂白中对氯气用量的减少以及对漂白过程中纸浆木质纤维组分变化的影响。结果表明:经过木聚糖酶预处理,在保证纸浆漂后白度的同时,氯气用量可以减少50%;木聚糖酶预处理对纸浆中的木素有脱除作用,且能促进木素在碱抽提过程中的溶出,但木聚糖酶对戊聚糖和纤维素也有不同程度的降解作用;酶处理浆漂后的木素和半纤维素的含量略低于未经处理的对照浆,纤维素含量则略高于对照浆。     

ENZYMATIC DEINKING OF OLD NEWSPRINT WITH CELLULASES AND XYLANASE

The enzymatic deinking and fiber modification of old newsprint (ONP) with several cellulases and xylanase were investigated and the suitable enzyme candidates were selected for ONP deinking in this paper. The results demonstrated that the cellulases and hemicellulases could significantly improve the deinking efficiency and fiber modification.Moreover, the synergistic effects of Novozym342 and xylanase (HC) can further enhance the deinking performance, reduce the dirt count and improve the brightness of resulting pulp. Additionally, compared to deinked pulps, obtained from conventional chemical materials, enzymatically deinked pulps had better bleachability, and the brightness of the bleached pulp reached 59.1% ISO, 9% ISO higher than the unbleached pulp.     

马尾松硫酸盐浆两段氧脱木素的影响因素

研究了马尾松硫酸盐浆段间不洗涤时第二段氧脱木素的影响因素。结果表明,在给定的第一段氧脱木素的条件下,第二段氧脱木素采用氧压0．4－0．5MPa、温度80－90℃、时间40－60min、碱用量（质量分数）2％－4％的条件,可以在纸浆粘度不致降低很大的前提下,得到较高的木素总脱除率。     

云南松-兰桉混合蒸煮制浆的研究

根据云南松、兰桉的化学成分、组织结构,选择出蒸煮的工艺路线,并进行了云南松、兰桉按不同比例混合蒸煮的实验研究,发现云南松-兰桉混合制浆是可行的.按常规硫酸盐蒸煮以兰桉占60%为好,最佳工艺为170-150-23-20(最高温度-保温时间-硫化度-用碱量),而按改良的硫酸盐蒸煮(利用深度脱木素技术的蒸煮),在显著降低成浆的K值(高酸钾值)的同时,浆的得率比常规硫酸盐蒸煮提高(平均提高2%-3%),合适的兰桉比例为50%、60%、70%,较好的工艺为165-150-23-25.     

固着剂助留剂协同控制纸浆溶解与胶体物质的机理

 将聚胺固着剂（PA）、阳离子聚丙烯酰胺助留剂（CPAM）单独以及协同处理旧新闻纸浆,采用聚焦光束反射测定仪（FBRM）考察浆料中残余胶体粒子的数量、尺寸和尺寸分布,探讨固着剂/助留剂协同控制纸浆中溶解与胶体物质（DCS）的效果和机理。结果表明,PA单独处理纸浆时,会产生部分不能固着于纸张纤维或不被纤维网络截留的粒子聚集体;CPAM单独处理纸浆时,其电荷容易被DCS中和,导致其减少纸浆胶体粒子数量的效果明显下降,但不产生粒子聚集体;PA/CPAM协同处理纸浆时,后续的CPAM处理能将PA预处理纸浆时产生的部分粒子聚集体进一步固着到纸张纤维上,达到更好地降低胶体粒子数量的效果,且不产生更大的粒子聚集体。     

土法造纸木素降解之探索──Ⅱ.嫩毛竹自然制浆过程中的化学成分变化及其分析方法

对江西三处嫩毛竹自然制浆过程中的化学成分变化进行了测定，得知在此过程中，嫩竹木素下降50％～70％；半纤维素下降20％～30％；纤维素含量相对提高25％～45％。不同的土法制浆工艺得到不同质量的纸张，其化学成分也有明显差异。同时在实验室模拟了嫩竹发酵过程，对其化学成分变化进行了监测。结果表明，经2．5％石灰液浸泡嫩竹70d（室温），木素含量下降45％左右，半纤维素变化很小；用天然水浸泡嫩竹70d（室温），半纤维素略有下降，木素则几乎没变，先用石灰水预浸3周，再改用自选的芽抱菌液浸泡嫩竹，经1周就达制浆水平，木素下降59％。还对分析方法做了些探索。     

纸浆的酶生物漂白及其机理

应用白腐菌（Ｗｈｉｔｅｒｏｔｂａｓｉｄｉｏｍｙｃｅｔｅｆｕｎｇｕｓ）产生的降解木素的三种酶类木素过氧化物酶［（Ｌｉｇｎｉｎｐｅｒｏｘｉｄａｓｅ，Ｌｉｐ）（ＥＣ．１．１１．１．１４）］、锰过氧化物酶［（Ｍｎ－ｐｅｒｏｘｉｄａｓｅ，ＭｎＰ）（ＥＣ．１．１１．１．１３）］和漆酶［（Ｌａｃｃａｓｅ，Ｌａｃ）（ＥＣ．１．１０．３．２）］及黑曲霉（Ａ．ｎｉｇｅｒ）产生降解半纤维素的聚木糖酶［（Ｘｙｌａｎａｓｅ）（ＥＣ．３．２．１．４）］和桉木（Ｅｕｃａｌｙｐｔｕｓ）硫酸盐浆作用，结果显示，酶处理能降低纸浆的卡伯值（Ｋａｐｐａｖａｌｕｅ），提高白度，而对粘度降低较少．ＧＣ和ＦＴＩＲ分析表明，经酶处理后，纸浆中的发色基团和助色基因减少，阿拉伯糖和木糖含量降低，按木ＫＰ浆木素－碳水化合物复合物（ＬＣＣ）的木素－阿拉伯糖基及木素－木糖基结合键断裂，并活化木素分子的芳香环结构，促进木素的溶出，提高了纸浆的白度和可漂性．生物漂白废液的污染负荷降低了．     

速生针叶木改良硫酸盐法制浆及其原理

对我国引种的南方湿地松和加勒比松进行了实验室改良硫酸盐法蒸煮的研究。结果表明,改良硫酸盐法制浆的选择性明显高于常规蒸煮法,当卡伯值相同时,与常规硫酸盐浆相比,改良硫酸盐浆具有相近的细浆得率、较低的粗渣率和较高的粘度,在相同的抗张指数下有更高的撕裂强度。