日本落叶松硫酸盐浆漂白特性

为了解日本落叶松的纸浆物理性能,以日本落叶松KP浆为原料,对纸浆的漂白特性进行了系统研究.结果表明:在常规CEH三段漂白中,最佳有效氯质量分数为8%,NaOH质量分数为2.5%,漂白纸浆白度可达到71%(ISO);在CDEHD漂白中,最佳有效氯质量分数为9%,EH段合理NaOH质量分数为2%,纸浆白度能够达到81%(ISO);在D/CE1D1E2D2和DE1D1E2D2漂白中,当总有效氯质量分数为7.9%时,两种漂白流程都能将纸浆漂到82%(ISO)的高白度.采用过氧化氢加强氧漂再加两段过氧化氢漂白的漂白流程(即OpQP1P2)可以将白度为27.3%(ISO)的纸浆漂到76.6%(ISO).     

白腐菌改性桉木CTMP浆的漂白研究

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%.     

蔗渣浆的压力过氧化氢漂白

对烧碱-蒽醌(Soda-AQ)法蔗渣浆分别进行了螯合预处理(Q)和常压过氧化氢(P)、压力过氧化氢(PO)漂白的研究,探讨了单段PO漂白蔗渣浆的可行性.正交试验结果表明,PO漂白蔗渣浆优化的漂白条件为漂白温度100℃、时间80min、压力0.6MPa、NaOH用量0.4%.PO漂白浆的白度较高,达84.0%ISO,特性黏度为825.3mL/g,比QP漂白浆的白度高9.9%ISO;PO漂白浆的物理强度性能也较好,浆料的抗张指数为66.67N.m/g,撕裂指数为9.34mN.m2/g,耐破指数为4.31 kPa.m2/g,耐折度为39次.PO漂白废水的化学耗氧量、生化耗氧量及色度较低,漂白废水可全部逆流回用,大大减少了污染排放.     

蔗渣氧脱浆二氧化氯漂白工艺参数的优化

采用三因素二次通用旋转组合实验设计,对蔗渣氧脱浆二氧化氯漂白的主要工艺参数(ClO2用量、NaOH用量和漂白时间)进行了优化,建立了工艺参数与纸浆卡伯值、白度及可吸附有机卤化物(AOX)产生量之间的二次多项式非线性回归数学模型.结果表明:通过实验设计建立的数学模型回归显著,失拟不明显;3个工艺参数对纸浆卡伯值、白度及AOX产生量的影响由大到小的顺序均依次为ClO2用量、漂白时间、NaOH用量;在优化模拟得到的较佳工艺条件(ClO2用量0.79%,NaOH用量0.43%,漂白时间53 min)下,纸浆卡伯值为1.83,白度为73.3%ISO,废水中AOX质量浓度为10.8 mg/L,与验证实验得到的纸浆卡伯值(1.76)、白度(75.0%ISO)和废水中AOX质量浓度(11.3mg/L)接近.     

蔗渣浆ECF短序漂白流程的对比

对典型的蔗渣浆无元素氯(ECF)短序漂白流程D0EpD、OpDEp及OpD进行了对比,探讨了二氧化氯脱木素(D0)与过氧化氢强化氧脱木素(Op)的脱木素效率差异及对后续漂白的影响,并分析了漂白过程中可吸附有机卤化物(AOX)的产生量和各漂白流程的直接化学品成本.结果表明:D0段脱木素选择性好,ClO2用量为0.8%时脱木素率即达40%以上,且用量越高脱木素作用越强;Op段在脱出纸浆中残余木素的同时能大幅提升纸浆白度,纸浆白度明显高于D0浆;相同后续漂白化学品用量下,OpDEp漂后浆白度高于D0EpD漂后浆白度,且比OpD漂后浆白度约高12个百分点;相同纸浆白度下,OpDEp漂白过程中产生的可吸附有机卤化物总量约为D0EpD的50%,其直接化学品成本比后者低约40.00元/t,具有更好的环境、经济效益.     

新型造纸原料洋麻的硫酸盐法制浆及ECF漂白

以洋麻为研究对象,分析了洋麻的化学成分,研究了不同H因子下硫酸盐法制浆(KP)的较优工艺,以及KP浆的ECF漂白性能及较优的漂白工艺.结果表明:洋麻的硝酸-乙醇纤维素含量为45.00%,酸不溶木素含量为16.50%,聚戊糖和抽出物含量均较低,是优良的造纸用原料;KP法蒸煮较优的制浆工艺为H因子1000、活性碱用量20%、硫化度22%,该工艺下细浆得率达44.9%、卡伯值为20.4、残碱质量浓度为11.67 g/L;ECF漂白的较优ODED漂白工艺为OD0,2%EpD1,1.5%,该工艺条件下终漂浆白度可达82.3%ISO.     

碱性H_2O_2处理蔗渣化学浆的漂白效应

目前采用次氯骏盐漂白纸浆纤维的损伤大,废水严重污染.研究采用无污染漂白剂H_2O_2探索了总碱、碱比、预处理和漂温等对漂白过程的影响和作用机理,指出H_2SO_4预处理后的蔗渣化学浆,在NaOH用量1.5%、Na_2SiO_3用量3.5%、MgSO_4用量0.05%、70℃的漂温下漂白2小时H_2O_2消耗2.367%,经草酸适当的中和还原后,漂浆的白度从39.5%(SBD)提高到7l%,白度增值高,白度的稳定性好,得率也高,因之H_2O_2漂白剂是发展我国草浆漂白有前途的力法.     

越南甜竹制浆漂白性能的研究

以越南甜竹为研究对象,经KP法蒸煮后,进行 DEpQP漂白,系统分析了其制浆漂白性能。KP法蒸煮适宜工艺条件为:碱(NaOH计)、硫、AQ质量分数分别为22%、20%、0.1%,液比为1∶4,最高温度为170℃,保温时间120min. 蒸煮结果为:粗浆得率381%, Kappa值1847,白度2525%(ISO)。采用单因素法研究DEpQP漂白中D段ClO2、Ep段H2O2、P段H2O2的最佳用量,漂白结果为:卡伯值114,白度 7932%(ISO),黏度9314mL/g.     

稳定脱墨浆过氧化氢漂白和抑制硅酸盐结垢的双功能助剂的研究

研究了不同螯合剂对脱墨浆过氧化氢漂白的稳定作用以及不同硅酸盐阻垢剂对硅酸盐垢的分散作用.复配出一种既可以稳定过氧化氢漂白又可以抑制硅酸盐结垢的双功能助剂(以质量分数计,DTPMPA 2.25%、DTPA 4.50%、EDTA 4.50%、硅酸盐阻垢剂A 15.00%,蒸馏水73.75%).使用此助剂进行一段过氧化氢漂白,漂浆ISO白度可达到58%,比单独使用DTPMPA,ISO白度提高2.5%.     

马尾松磨木浆H2O2高白度漂白的研究

H2 O2 是一种常用的氧化性漂白剂 ,本研究对马尾松磨木浆 (SGW )进行了单段H2 O2 漂白和两段H2 O2漂白试验 ,确定了H2 O2 漂白的最佳工艺参数。当采用两段H2 O2 漂白时 ,纸浆白度可由原浆的 4 7 8%提高到74 5 % ,按此法制得的漂白浆能满足低定量高白度胶印新闻纸和其它高级纸种的生产要求     

MODIFIED OPAL:A NOVEL STABILIZER FOR HYDROGEN PEROXIDE BLEACHING OF PULPS

The possibility of modified opal as the stabilizer of hydrogen peroxide bleaching was investigated. The results showed that the modified opal in place of sodium silicate as the stabilizer of hydrogen peroxide bleaching is feasible. At the same dosage, above 3% ISO can be increased for both wheat straw pulp and deinked pulp. The stabilizing ability of the modified opal to hydrogen peroxide bleaching of pulp is improved markedly. It is favorable for bleaching to increase temperature and time within a permissive extent. The suitable process conditions are 10% of pulp consistency, 3% of hydrogen peroxide, 1.5% of sodium hydroxide, 3% of the modified opal, 70℃ and 60 min when the modified opal is used as the stabilizer of hydrogen peroxide bleaching. At these conditions, the brightness gain can reach about 16% ISO for wheat straw pulp. In addition, it is favorable for bleaching to add a little magnesium sulfate when the modified opal is used as the stabilizer of hydrogen peroxide bleaching, the brightness of pulp can increase I%ISO if0.05% of magnesium sulfate is added. The cost analysis indicated that the modified opal is superior to sodium silicate as the stabilizer of hydrogen peroxide bleaching in economical aspect and has further the potential of market development.     

HE EFFECT OF TRANSITION METAL IONS-IRON ON HYDROGEN PEROXIDE BLEACHING

Hydrogen peroxide bleaching has been extensively used in high-yield pulp bleaching. Unfortunately,hydrogen peroxide can be decomposed under alkaline condition, especially when transition metal ions exit. Experiments show that the valence of transition metal ion is also responsible for the decomposition of hydrogen peroxide.Iron ions are present in two oxidation states, Fe2+ and Fe3+. They are both catalytically active to hydrogen peroxide decomposition. Because Fe3+ is brown, it can affect the brightness of pulp directly, it can also combine with phenol, forming complexes which not only are stable structures and are difficult to be removed from pulp, but also significantly affect the brightness of pulp because of their color.Sodium silicate and magnesium sulfate, when used together, can greatly decrease hydrogen peroxide decomposition. The optimum dosage of sodium silicate is about 0.1% (on solution) for Fe2+ and 0.25% (on solution) for Fe3+. Adding chelants such as DTPA or EDTA with stabilizers simultaneously can obviously improve pulp brightness. For iron ions, the chelate effect of DTPA is better than that of EDTA.Under acidic conditions, sodium hyposulfite and cellulose can reduce Fe3+ to Fe2+ effectively, and pulp brightness is improved greatly. Adding sodium thiosulfate simultaneously with magnesium sulfate,sodium silicate, and DTPA to alkaline peroxide solution can result in higher brightness of pulp.pH is a key parameter during hydrogen peroxide bleaching, the optimum pH value should be 10.5-12.     

THE EFFECT OF TRANSITION METAL IONS-IRON ON HYDROGEN PEROXIDE BLEACHING

INTRODUCTIONHydrogen peroxide bleaching has been extensively used in high-yield pulp bleaching. IT is well known that hydrogen peroxide can be easily decomposed under alkaline conditions, especially in the presence of transition metal ions due to their catalyzing effect on the decomposition of hydrogen peroxide. Some recent reports show that the valence of transition metal ion can have a drastic effect on the decomposition of hydrogen peroxide.Generally, iron can exist in Fe2+ and Fe3+…     

STUDY ON THE ELEMENTAL CHLORINE FREE BLEACHING OF BAMBOO KRAFT PULP

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…     

BLEACHING OF SULFONATED CMP FROM BIO-TREATED WHEAT STRAW

INTRODUCTIONThe increasing consumption of paper and paper board all over the world and the more and more serious legislative constraints on forest resources intensify the shortage of pulping materials. Agricultural residues such as wheat straw are of increasing interests in countries and areas which have abundant plantation of agricultures and are lack of wood supply. One of the problems associated with the wheat straw pulp was the low pulp yield and low bleachability relative to wood pulp…     

金属离子在高温过氧化氢漂白中的影响与控制

研究了纸浆中通常存在的金属离子对硫酸盐法美国南方松氧脱木素浆高温过氧化氢漂白结果的影响以及对金属离子的控制方法。比较了锰,铜,铁、钙等离子对浆料白度,粘度及卡伯值的相关性和有关的变化规律。实验证明采用预处理方式和漂白中使用适量的螯合剂ＤＴＭＰＡ可以有效控制金属离子的负面影响,在过氧化氢用量４％时可使漂浆白度从２７．４％ＩＳＯ提高到８０％ＩＳＯ以上,漂浆质量得到明显改善。     

蔗渣浆的全无氯漂白工艺

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.     

蔗渣浆全无氯漂白的研究

本本文探讨了在Op段低NaOH用量,P段低H2O2用量的条件下采用OpQP流程将蔗渣浆漂至82%ISO的可行性,并讨论了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-2,PP-1耐高温、高压,可用于压力过氧化氢漂白。在Op段2%NaOH,0.5%H2O2;P段3% H2O2,PP-1 0.1%, PP-2 0.5%条件下,蔗渣浆采用OpQPo流程,漂后浆白度达到85%ISO。OpQPo从根本上消除了AOX的产生,经测定漂白废水属于可生物降解废水,只有Q和P段的部分废水进入废水处理系统, 容易通过常规的污水处理方法达到日益严格的国家排放标准。     

微波辐射应用于麦草浆漂白工艺的研究

将微波辐射代替传统水浴加热应用于H2O2麦草浆漂白工艺中。研究了微波辐射时间、辐射功率、H2O2用量和NaOH用量等因素对纸浆漂白效果的影响。通过与传统水浴加热漂白对比发现,达到相应白度时微波辐射漂白时间大大缩短;微波辐射漂白纸浆粘度没有过多下降;微波辐射漂白废水中的残余过氧化物只有水浴漂白的10%。正交实验结果表明H2O2用量的影响最大,其次是微波辐射时间和NaOH用量,影响最小的是微波输出功率。最佳实验条件为微波辐射功率240?W、辐射时间25?min、H2O2用量5％和NaOH用量4％时纸浆白度约为59％ISO,纸浆粘度大于620?mL·g-1,纸浆硬度约为390。