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1.
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   

2.
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   

3.
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   

4.
采用常规碱抽提(E)、氧加强的碱抽提(EO)、H2O2强化的碱抽提(EP)、氧和H2O2强化的碱抽提(EOP)对ClO2脱木素(D0)麦草浆进行改性,考查不同碱抽提方式的改性效果在后续漂段(D1)的体现,并就不同无元素氯(ECF)漂白流程(D0ED1、D0P、D0A/QP、D0EP、D0EPD1、D0EPP)进行对比.结果表明:不同碱抽提方式对D0浆木素的改性效果不同,就对后续漂段D1的影响而言,4种不同碱抽提方式下纸浆的可漂性顺序为D0EOPD0EPD0EOD0E;在4种碱抽提方式所对应的D0ED1漂白流程中,D1段ClO2用量的增加对白度的提升是有限的,以0.8%~1.0%为佳;D0EPD1和D0EPP流程漂白效果优于其它流程,采用D0EPD1和D0EPP流程漂后白度可分别达到82.3%ISO和83.8%ISO,均适用于麦草浆短序ECF漂白.  相似文献   

5.
摘要:采用四种不同的碱抽提方式对麦草浆二氧化氯漂白(D0)进行强化,考查了不同碱抽提方式的强化效果,并对不同ECF漂白流程进行了对比研究。结果表明:在D0ED1漂白流程中,不同碱抽提方式对D0木素的修饰效果不同,就后续D1漂段而言,四种不同碱抽提模式下纸浆的可漂性顺序为:D0EOP>D0EP>D0EO>D0E。在D0ED1漂白流程中,D1段ClO2对白度的提升是有限的,达到白度极限后再增加ClO2用量对白度提高不明显。本实验条件下D1段ClO2用量以1.0%~1.2%为佳。从D0ED1与D0EP各漂白流程的对比来看,在终段漂白中以P取代D1效果要好,表明H2O2用于终段漂白其效果要好于ClO2。从其它ECF漂白流程的对比来看,D0EPP和D0EOPP流程漂白效果优于其它流程。本实验条件下采用D0EPP和D0EOPP漂白流程,麦草浆漂后白度可分别达到83.8%和85.7%。  相似文献   

6.
采用分子改良后的木聚糖酶对芦苇浆进行生物预处理,考察了改良木聚糖酶辅助漂白的效果。结果表明,酶预处理可以降低CEH三段漂白中氯化C段的氯气用量60%。改良木聚糖酶预处理辅助漂白芦苇纸浆最佳条件为:pH为7.0,温度60℃,浆浓(质量分数)5%,酶用量12μmol/(min.g),预处理时间60 min。在此条件下C段氯用量降至对照的40%时,酶处理漂后样品白度可达到84.0%(ISO),高出对照样的白度3.7%(ISO)。改良木聚糖酶预处理还能够改善纸浆漂后样的物理性能。  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.
The influences of chlorine dioxide bleaching of NaOH-AQ wheat straw pulp were studied in this paper. The results showed that the optimal conditions were as follows: chlorine dioxide dosage 1.0%,initial pH 4.0, pulp consistency 8% and 70℃ for 150 minutes. Furthermore, some ways of rebuild the conventional CEH bleaching sequence were put forward, such as CED, DED, DCED, and we draw a conclusion that CED, DCED has higher bleaching efficiency than the CEH bleaching process.  相似文献   

9.
用正交实验法探讨了在微波辐射下次氯酸钠漂白硫酸盐竹浆的工艺条件,结果表明,微波辐射用于硫酸盐竹浆次氯酸盐单段漂白的最佳工艺条件为:微波辐射功率480W,辐射时间2min,用氯量4.29%,氢氧化钠用量1%,浆料浓度12%.在此条件下,纸浆白度可达72.9%IS0;而在相同条件下达到此白度,传统水浴加热则需要90min的时间。因此,微波辐射竹浆次氟酸钠单段漂白能节约能源和提高生产效率.  相似文献   

10.
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   

11.
研究了用镁碱代替钠碱的马尾松化学预热机械浆(CTMP)浆过氧化氢漂白工艺及其对纸浆性能的影响,分析了镁碱和钠碱过氧化氢漂白废液对环境的影响.试验结果表明,马尾松CTMP浆镁碱漂白过氧化氢的最佳漂白工艺条件为:H2O2体积浓度为4%,Mg(OH)2质量浓度为1.2%,Na2SiO3质量浓度为1.5%、漂白温度为80℃、漂白时间为120 min,其白度可至63.5%(ISO),而经钠碱漂白后纸浆的白度值为61.4%(ISO).镁碱过氧化氢漂白废液化学耗氧量(CODcr)为193.6 g/L,比钠碱过氧化氢漂白废液化学耗氧量(CODcr=312.86 g/L)降低了38.12%.  相似文献   

12.
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   

13.
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   

14.
INTRODUCTIONXylanase pretreatment can produce many small holes on pulp surfaces and cross section by removing part xylose that may be sucked back or exists in style of LCC. Thus penetrability of following chemicals. Olsen [1] observed coordinated pretreatment of xylanase and lignin enzyme (compound of lignin peroxide enzyme and manganese peroxide enzyme) had better delignification than sole xylanase and sole laccase lignin enzyme. So we can forecast that coordinated pretreatment of xylan…  相似文献   

15.
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   

16.
利用白腐菌改性处理可以显著提高机械浆的强度性能,有利于拓宽机械浆的应用范围.本文采用白腐菌Trametes hirsute 196对桉木CTMP浆进行改性处理,并探讨了白腐菌处理后纸浆的漂白工艺.研究结果表明:白腐菌处理使桉木CTMP浆白度值从49.6%下降到37.8%,且这种改性后纸浆的可漂性较差,H2O2和Na2S2O4单段漂后纸浆白度均在60%以下,但采用Na2S2O4—H2O2两段组合漂白工艺可以使漂后Bio-CTMP浆白度达到71.3%.  相似文献   

17.
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   

18.
The potential use of Samaar Morr (JUNCUS A CUTUS) plant as fibrous material in papermaking was evaluated in this study. The chemical analysis and fibre charactersitcs of this plant were determined for better understanding its behaviour in papermaking. Samaar morr stalks were subjected to sulfur-free three-stage (peroxyformic acid, formic acid, peroxyformic acid) Milox process. Some conventional pulping experiments such as soda,soda-anthraquinon (S-AQ), kraft and kraft-AQ pulping in addition to two- and one-stage peroxyformic acid pulping were also carried out for comparison with the three-stage peroxyformic acid pulping method. It was found that the pulping with Milox process produces pulp with good properties compared to the pulp produced from the other methods. The physical and optical properties of different pulps were also examined. The behaviour of Milox samaar morr pulp towards bleaching with alkaline hydrogen peroxide has been investigated in presence and absence of formic acid. The results showed that the final brightness about 81.5% ISO could be achieved after 3% peroxide in two bleaching steps with formic acid treatment between the two steps.  相似文献   

19.
蔗渣浆的全无氯漂白工艺   总被引:1,自引:0,他引:1  
对蔗渣浆采用过氧化氢强化的氧脱木素(OP)-螯合预处理(Q)-压力过氧化氢漂白(PO)的短序漂白,探讨了将蔗渣浆漂至82%ISO和用非硅过氧化氢漂白稳定剂代替硅酸钠用于过氧化氢漂白的可行性.研究表明,非硅过氧化氢稳定剂PP-1与PP-2耐高温、耐高压,可用于压力过氧化氢漂白.OP段氢氧化钠用量为2.0%(相对于绝干浆质量,下同)、过氧化氢用量为0.5%,PO段过氧化氢用量为3.0%、PP-1用量为0.1%、PP-2用量为0.5%时,蔗渣浆采用OPQPO流程漂白后,浆的白度可达到85%ISO.而且OPQPO从根本上消除了可吸附有机卤化物的产生;经测定,漂白废水属于可生物降解废水.  相似文献   

20.
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   

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