首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
探讨了嗜热真菌耐热木聚糖酶助漂针叶木硫酸盐浆的应用前景.着重研究了应用耐热木聚糖酶进行生物助漂的酶用量、酶处理的pH值以及漂白用氯量等影响因素.结果表明,在不影响纸浆的各项性能的情况下,经酶处理的纸浆白度相比对照增加1.06%~5.11%ISO.同时,酶处理纸浆漂白时可减少漂白用氯量.另外,在偏碱性条件下进行酶处理对纸浆漂白效果的影响较为显著.纸浆纤维的扫描电镜结果显示,酶未对纤维造成损伤,而是改善了纸浆纤维的可漂性.该耐热木聚糖酶非常适宜应用于酶助漂.  相似文献   

2.
分析了漂白针叶木化学浆、针叶木机械浆、再生浆和漂白芦苇化学浆的总电荷、表面电荷量。讨论了它们对反应性聚丙烯酰胺纸张增强性能和助滤性能的影响。研究结果表明,浆的表面电荷越大,N-氯代聚丙烯酰胺呈现最大的纸湿增强效果和助滤效果所需的定着助剂PDADMAC的量也愈大。  相似文献   

3.
1.INTRODUCTIONThe microparticles retention and drainage technologywas brought in 1980s. It brings striking effect whenused in wet-end in paper-making. The retention offines and fillings and the drainage of pulp improved alot, meanwhile, the evenness also improved. So, mi-croparticles retention and drainage system is the maindeveloping direction of retention and drainage aids on paper-making industry.All microparticles in microparticle system we use currently are inorganic anionic. It rea…  相似文献   

4.
1INTRODUCTIONChina is a country using the most variety of non-wood fiber raw material and is the largest country producing non-wood fiber pulp and paper in the world[1]. Bamboo is one kind of the main non-wood species for papermaking in China. Although the structure of raw materials for papermaking has being adjusted through increasing the proportion of wood pulp and by effectively utilizing waste paper source, non-wood species will still remain an important fiber resource[1,2].At present…  相似文献   

5.
Thc zeta potential and cationic demands of various kraft pulps - unbleached, bleached and beaten to different freeness levels were determined in the laboratory. The zeta potential of pulp where the final stage was a lignin degrading and dissolving treatment such as alkaline extraction or hypochlorite was lower than the unbleached pulp. The cationic demand of unbleached pulp was higher compared to that of bleached pulp. Beaten pulps showed larger cationic demands than the unbeaten pulps, which can be attributed to the larger specific surface area of pulp components. Fibres become increasingly electronegative when beaten and therefore cationic demand of pulps increases with beating. When the zeta potential method is used with furnishes of different freeness,the linear relationship is observed. However, the slope is decreasing with the decrease in freeness of the pulp.  相似文献   

6.
INTRODUCTIONIn papermaking, it is very often that more than one type (or grade) of pulps are used to develop paper sheet properties necessary for both machine runnability and requirement from the end users. In many high end paper grades (e.g., various high brightness printing/writing papers), long fiber from softwood bleached kraft pulp traditionally is often used in combination with short fiber from hardwood bleached kraft pulp (HBKP). In this combination, the long fiber component provi…  相似文献   

7.
采用2,2,6,6-四甲基哌啶—1—氧自由基(TEMPO)为介质的氧化法氧化浆料和纸张回收一次的浆料,研究浆料氧化后对纸张性能、回收纸性能的影响。研究结果表明氧化法可提高纸浆的羧基含量,降低回收纤维的角质化,当氧化时间为20m in时,回收纸的性能最佳,与未氧化浆料的回收纸相比,紧度提高23.0%,抗张指数提高96.4%,耐破指数提高93.1%,耐折度提高333.3%,撕裂指数降低7%。电镜分析表明氧化浆料抄成的纸经一次回收后,纸张表面纤维的结合比未氧化浆料的回收纸张结合紧密。  相似文献   

8.
进行了桉木硫酸盐将漆酶一介体系统(LMS)生物漂白的研究,漆酶由白腐菌Panus conchatus固体发酵并分纯化而制得;一种新的介体--N-羟基乙酰苯胺(NHA)自行合成,采用L/MQP漂白流程,仅用2%(质量分数)的H2O2就将桉木常规硫酸盐浆(EMCC-O)可达到87.6%ISO的白度,生物漂白的CK浆和EMCC-O浆的粘度都很高,说明漆酶/NHA生物漂白的脱木素选择性很好。  相似文献   

9.
研究了菠萝叶的纤维形态及化学成分,比较了菠萝叶的硫酸盐法和烧碱法制浆工艺,同时探讨了浆料的漂白性能.试验结果表明,菠萝叶是一种良好的长纤维造纸原料,其碱法浆性能好,利用次氯酸盐二段漂白可使浆的白度达到70%.  相似文献   

10.
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…  相似文献   

11.
 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。  相似文献   

12.
The Calabrien pine (Pinus brutia) wood chips prior to kraft pulping were biologically pre-treated with selected white-rot fungi (Ceriporiopsis subvermispora), which was recorded to be preferentially attacking the lignin component of the wood. The effects of this treatment on beating performance and physical strength of resultant papers were studied in detail. Bio-treated samples showed comparable and, in most cases, higher physico-mechanical properties than those obtained from untreated controls. Under the same beating conditions the bio-treated kraft pulp was noted to have the lower SR' indicating a lower degree of external fibrillation. The paper made from bio-treated kraft pulp has a higher density, tensile property, air permeability and swellability. Furthermore, remarkable energy savings up to 33 % were observed when beating bio-treated kraft pulp. This study contributes to a better understanding of the mechanisms taking place during bio-treatment and the modification processes of cell wall components.  相似文献   

13.
The Calabrien pine (Pinus brutia) wood chips prior to kraft pulping were biologically pre-treated with selected white-rot fungi (Ceriporiopsis subvermispora), which was recorded to be preferentially attacking the lignin component of the wood. The effects of this treatment on beating performance and physical strength of resultant papers were studied in detail. Bio-treated samples showed comparable and, in most cases, higher physico-mechanical properties than those obtained from untreated controls. Under the same beating conditions the bio-treated kraft pulp was noted to have the lower SR° indicating a lower degree of external fibrillation. The paper made from bio-treated kraft pulp has a higher density, tensile property, air permeability and swellability. Furthermore, remarkable energy savings up to 33 % were observed when beating bio-treated kraft pulp. This study contributes to a better understanding of the mechanisms taking place during bio-treatment and the modification processes of cell wall components.  相似文献   

14.
This paper discusses the refining of bleached eucalyptus kraft pulp (BEKP).Pilot plant tests were carried out in to optimize the refining process and to identify the effects of refining variables on final paper quality and process costs.The following parameters are discussed: pulp consistency, disk pattern design, refiner speed,energy input, refiner configuration (parallel or serial)and refining intensity.The effects of refining on pulp fibers were evaluated against the pulp quality properties, such as physical strengths, bulk, opacity and porosity, as well as the interactions with papermaking process, such as paper machine runnability, paper breaks and refining control.The results showed that process optimization,considering pulp quality and refining costs, were obtained when eucalyptus pulp is refined under the lowest intensity and the highest pulp consistency possible. Changes on the operational refining conditions will have the highest impact on total energy requirements (costs) without any significant effect on final paper properties.It was also observed that classical ways to control the industrial operation, such as those based on drainage measurements, do not represent the best alternative to maximize the final paper properties neither the paper machine runability.  相似文献   

15.
INTRODUCTIONAlthough NSSC and mechanical pulps have partly replaced kraft pulps in containerboard manufactur-ing, kraft is the dominant pulping process in our in-dustry. At different paper mills significant efforts have been made to increase the pulp yield without major investments during the past few years. In prin-ciple, the increase in pulp yield can be accomplished by (a) decreasing polysaccharide depolymerization during pulping process thereby increasing the carbo-hydrate content …  相似文献   

16.
纤维细胞充填技术在机械浆中的应用   总被引:1,自引:0,他引:1  
分析了浆浓、转速、CO2气体压力、反应时间对机械浆纤维细胞充填效果的影响。比较了漂白化学热磨机械浆(BCTMP)和杨木碱性过氧化氢机械浆(APMP)的纤维细胞充填效果。结果表明:转速是影响机械浆纤维细胞充填效果的关键因素。纤维细胞充填技术应用于机械浆是可行的,与直接加填相比,当BCTMP成纸内聚力提高1786%、裂断长提高42.86%、耐破度提高42%时,灰分同时提高2.05%;当APMP成纸内聚力分别提高21.31%、6.56%和1.64%,裂断长分别提高69.18%、77.40%和7534%,耐破度分别提高18.18%、22.73%和25%时,灰分分别提高9.62%、10.58%和1.68%。APMP的纤维细胞充填效果较BCTMP的效果更好。  相似文献   

17.
用速生高产红麻全秆,采用亚铵法红麻全秆浆代替木浆生产牛皮箱板纸。质量全部符合国家规定标准。  相似文献   

18.
对4种竹材硫酸盐浆与马尾松木浆配抄纸袋纸和牛皮纸进行了研究和比较。结果表明,慈竹最容易蒸煮而且纸浆得率和强度最高,桉竹次之,甜竹不如桉竹,麻竹最差。当竹浆配入量为20%时,慈竹浆和桉竹浆配抄的纸袋纸的强度比甜竹浆和麻竹浆配抄的纸袋纸高,其某些强度甚至比100%马尾松木浆抄造的纸袋纸还高;慈竹浆配抄的牛皮纸的各项强度较桉竹浆配抄的牛皮纸高,甚至超过100%马尾松木浆抄造的牛皮纸。  相似文献   

19.
研究了生物酶对未漂硫酸盐针叶木浆酶促打浆后打浆度和纸浆物理性能的影响,确定了酶促打浆的最佳工艺条件,探讨了BIO-RE100半纤维素酶在最佳打浆工艺下对打浆功耗的影响.研究结果表明,生物酶处理最佳工艺条件是:温度为40℃、酶用量为1000g/t、pH值为6、时间为60min.在此最佳条件下使用生物酶预处理浆料,打浆功耗可以降低33%,纸浆物理性能有所提高.扫描电镜分析结果表明,纤维表面剥蚀程度较大,细纤维化程度有所提高,纸浆纤维切断较少.  相似文献   

20.
Introduction Diamond likecarbon(DLC)coatingshavebeen increasinglyappliedtomechanicalcomponentsandpartsduetotheirveryattractivemechanical,chemical, physical,electricalandopticalpropertiessuchashighdegreeofhardness,extremelylowfrictionalcoefficient, highwear resistance,highthermalconductivity,highmodulus,chemicalinertnessandlowdeposition temperature[1].AsshowninFig.1,DLCismadeofcarbon andhydrogenanditsstructureisamorphousorquasi amorphous,whereasdiamondandgraphitearemadeof carbonbuttheirstru…  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号