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1.
A series of Reed Pulps were prepared in which the level of Non-Process Elements (NPEs), including calcium, manganese,copper,iron were seclectively enriched and depleted, these pulps were then oxygen delignification,and the pulps were characterized according to kappa number, viscosity,brightness. The results indicated that the enrichment of NPEs have an important effulence on delignification,pulp viscosity and brightness, iron is the most harmful during oxygen delignification but manganese is just like a kind of aid and can enhance brightness and delignification.  相似文献   

2.
1INTRODUCTIONNew pulping and bleaching technologies, which do not use chlorine-base chemicals, continue to be developed in the pulp and paper industry worldwide to meet stricter environmental regulation and increased public environmental awareness. ECF (Element-chlorine-free) and TCF (Total-chlorine-free) bleaching sequence had been used in bleaching plant to reduce the amount of chlorinated organic compounds in the bleach plant effluent. Oxygen delignification was gradually becoming a …  相似文献   

3.
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   

4.
Laccase has been proven that it has a good selectivity and efficiency in pulp bleaching. In this paper, the effects of LMS (Laccase Mediator System) treatment on delignification and bleaching of wheat straw pulp at various conditions, such as laccase dosage,temperature, oxygen pressure and pH, were investigated. The TCF sequence including LMS can bleach the wheat straw pulp to 81% ISO brightness with good strength. The synergetic biobleaching of LMS and xylanase of wheat straw pulp was also investigated. It was found that the final brightness and strength of synergetic biobleaching pulps increased to a certain extent and the bleaching selectivity was improved. The combination of the enzymes is feasible for the delignification and bleaching.  相似文献   

5.
酶处理对麦草碱法脱木素的影响研究   总被引:6,自引:0,他引:6  
研究了在麦草碱法脱木素前对麦草进行酶处理时酶用量、处理时间及洗涤方式等因素对碱法脱木素效果的影响 ,并对酶处理后麦草浆物理性能的变化进行了研究 .结果表明 ,在碱法脱木素前对麦草进行酶预处理 ,可以提高碱法脱木素效率 ,降低碱的消耗 ,同时还可以增加纸浆的白度和强度性能  相似文献   

6.
INTRODUCTIONNowadays, under the pressure of energy crisis, Methods押The pulp was put in the high-density polyethylene plastic bag in the of thermostatic water bath where the pulp was treated with chelated environment pollution and market competition, the pulp industry has being developed in the direction of "Three Highness" and " Three Lowness". "Three Highness" means high yield, high strength and high brightness; on the other hand, " Three Lowness" means low energy consumption, low wa…  相似文献   

7.
在麦草KP浆的无氯和少氯漂白程序中使用活化剂,可促进脱木素作用并提高浆的白度。在氧脱木素前用NO2,硫酸和过氧酸进行预处理比较,以NO2效果最佳。NO2用量2%,处理后浆的卡伯值比未处理降低了6%,白度提高4%,粘度只下降1.6%。在D/CEDD漂白程序中,漂前用对有效氯用量8%的S12预处理,白度提高2.3%ISD,粘度基本无变化;活化剂TA用于NOP三段漂的P段,用量4%(对浆),可提高白度4.3%ISO,粘度也有明显提高。本试验采用GOPAPTA无氯漂白程序,可使麦草kp浆漂后白度达80%ISO,但粘度下降较大  相似文献   

8.
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。  相似文献   

9.
In this paper, we have researched TCF bleaching on reed pulp including oxygen delignification, oxygen delignification with H2O2 intensification and H2O2 bleaching. The results show that Op-P bleaching process on NS reed pulp is suitable and the brightness of bleached pulp is up to 82% ISO.  相似文献   

10.
单段氧脱木素特性的研究   总被引:5,自引:3,他引:2  
研究了马尾松硫酸盐浆单段氧脱木素的特性,研究结果表明:影响马尾松硫酸盐浆氧脱木素的因素有:时间,温度,用碱量,氧压,保护剂MgSO4的用量及反应浆浓,从纸浆中木素的脱出和纸浆的粘度出发,各因素都有一较合适的用量,其中,氧压在0.5-0.6MPa之间,时间80min,温度100℃,NaOH用量3%-5%,MgSO4用量0.5%-1.0%,浆浓10%-12%,在以上条件并保证浆粘度不致降低很大的条件下,纸浆的木素脱出率较大。  相似文献   

11.
Carbohydrate degradation during oxygen bleaching is associated with cleavage reactions. It is apparent that the loss of the cellulose DP (degree ofpolymisation)is strongly affected by the extent of the delignification. A strong linear correlation can be established between the DP of cellulose chains and the residual lignin in the pulp. The Nuclear Growth concept and Percolation Theory for heterogenous system can be combined to formulate kinetic models for both the delignification and the degradation of carbohydrate. The models prediction is statistically robust and can be applied to different pulps at different bleaching conditions.  相似文献   

12.
氧脱木素的主要问题是提高其脱木素选择性,而氧脱木素过程中产生的含氧自由基是影响其脱木素选择性的主要因素.而本文用改进的Fenton反应Co2 -H2O2体系产生羟基自由基(HO.),用茜素紫3B的氧化来显色测定HO..将Co2 -H2O2体系与深度脱木素竹浆进行反应,并通过添加HO.捕获剂来控制HO.的数量,研究HO.与竹浆中木素和碳水化合物的反应情况.把HO.捕获剂作为助剂用于深度脱木素竹浆氧脱木素过程,研究HO.的量对氧脱木素过程的影响.研究结果表明,HO.能与木素和碳水化合物发生反应,具有脱木素作用,但对碳水化合物的降解也较严重.HO.捕获剂具有清除HO.的作用,在氧脱木素过程中加入HO.捕获剂能减少碳水化合物的降解,提高氧脱木素选择性.  相似文献   

13.
A comparative evaluation of DQP, OQP and CEH bleaching of non-wood fibres has revealed that wheat straw, reed, bagasse and bamboo pulps can be bleached to brightness levels of just above 80% ISO,when applying an OQP bleaching sequence and to brightness levels of about 85% ISO when applying the DQP sequence using 10 - 15 kg/tp of ClO2 (aC1.),15 - 20 kg/tp of H2O2 together with 1 - 2 kg/tp of EDTA. The P.C. numbers of the DQP and OQP bleached pulps are much lower and the viscosity much higher than those of the CEH bleached pulps.Compared with CEH pulps, both the DQP and OQP pulps had better strength properties, particularly Tear Index. In spite of their higher final brightness levels,the DQP pulps show similar or better strength properties than the OQP pulps. A comparison of the CEH and DQP effluents showed that the DQP bleaching could reduce the pollution load (CODCDBOD5, SS) by 35 to 60% without the need for recirculation of any effluent streams. The AOX levels could be reduced by 87 to 93%.  相似文献   

14.
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。  相似文献   

15.
KRAFT WOOD PULP TCF AND ECF BLEACHING WITH ENZYME PRETREATMENT *   总被引:1,自引:0,他引:1  
针叶木硫酸盐浆用木聚糖酶Irgazyme40_X4进行预处理,然后进行各种无元素氯(ECF)和全无氯(TCF)漂白.实验结果表明,酶预处理能提高后续漂白效果,提高白度,降低卡伯值,并改善纸浆的粘度,在不用元素氯的情况下,能将纸浆漂白到88%ISO以上的白度  相似文献   

16.
几种脱木素催化剂的催化原理及作用   总被引:1,自引:0,他引:1  
介绍了多金属氧酸盐 (同多金属氧酸盐和杂多金属氧酸盐 )、酰胺和杂菲的物理化学特性和机理 ,并对它们的催化效果进行了分析 .多金属氧酸盐可以显著地催化过氧化氢脱木素 ,催化过程中碳水化合物无严重降解 ,纸浆白度增加 ,且能较好地保持其粘度 ;酰胺对过氧化氢漂白具有明显的改善效果 ,可以有效地提高纸浆的白度 ,保持纸浆的粘度 ;杂菲能有效地提高过氧化氢漂白效果 ,但会导致碳水化合物的严重降解  相似文献   

17.
针对混合商品桉木片硫酸盐法制浆漂白过程强度损失较为严重问题,利用正交实验方法完成混合商品桉木片硫酸盐浆氧脱木素工艺优化,确定在NaOH用量2%、时间60,min、温度100,℃、氧压0.5,MPa、MgSO4用量0.2%的条件下,纸浆的打浆度为15°SR,其抗张指数达到39,N·m/g以上,黏度780,mL/g.通过单因素实验,进一步探讨氧脱木素工艺中NaOH用量对于纸浆性能的影响,提出氧脱木素工段NaOH用量与纸浆黏度、卡伯值分别具有线性关系:Yη=-17.84,XNaOH+829.92,R2=0.989,8;Ykappa=-0.62,X NaOH+10.56,R2=0.995,9.  相似文献   

18.
中浓纸浆清洁漂白技术的理论与实践   总被引:2,自引:1,他引:1  
纸浆传统低浓含氯漂白方法(如CEH)存在对环境污染、水耗和能耗大、不可能适应大产能的要求等问题,需要用中浓氧脱木素、中浓二氧化氯漂白、中浓过氧化氢漂白及它们的组合等清洁漂白技术来取代.文中结合各类清洁漂白技术的特点,研究适用于各浆种的中浓氧脱木素、中浓过氧化氢等漂白技术,结合工程实践,提出适合我国国情的中浓纸浆少污染漂白技术及全无氯漂白技术,从而满足日益严格的环保要求,实现清洁漂白生产.  相似文献   

19.
Poly (p-phenylene terephthalamide) (PPTA) pulp was prepared by polycondensation of the p-phenylene diamine (PPDA) with terephthaloyl chloride (TPC) in the completely anhydrous solvent system of N-methyl pyrrolidone (NMP) having calcium chloride, in the presence of poly (vinyl pyrrolidone) (PVP) having a viscosity average molecular weight lower than 40 000. It was confirmed that the polycondensation could be accelerated, the inherent viscosity of the polymer could be increased, and the polymers could be fibrillated more easily by the addition of the PVP. FTIR and X-ray spectra proved that PVP had not combined into molecular chains of the resultant PPTA pulps. The morphology of the resultant pulps, the effect of viscosity average molecular weight, amount and adding mode of PVP on inherent viscosity, specific surface area,and mean length of the resultant pulps were discussed in detail. And the friction and wear properties of the compound reinforced by the resultant pulps were simply investigated.  相似文献   

20.
对酸预处理 (A)和螯合剂预处理 (Q)过程中 ,金属离子含量和 pH值变化对荻苇浆过氧化氢漂白的影响进行了研究。结果证明 :螯合剂预处理比酸预处理有更好的效果 ,在 pH值为 3时螯合剂预处理能够使荻苇浆获得最佳白度。  相似文献   

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