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以慈竹为研究对象,对比研究了5种不同预处理方式及其浸渍效果;分别对预处理后物料进行制浆和漂白操作,比较不同预处理方式对制浆性能的影响;综合考虑技术经济因素,提出了适宜的化学预处理条件;研究了慈竹化机浆的漂白性能,并探讨了碱性过氧化氢制化机浆的漂白机理。分析了慈竹的化学组成、纤维形态等材性特征,结果表明。 相似文献
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采用螺旋挤压法破坏竹片组织结构,并筛除分离部分薄壁组织,选用不同的化学预浸渍方法进行浸渍软化,对制得的不同化学机械浆(CMP)进行过氧化氢漂白对比试验。结果表明:螺旋挤压法去除11.4%薄壁组织后,竹丝化学组成与原竹片相比差异十分明显,其灰分质量分数降低了38.6%,纤维素质量分数增加了4.71%,但螺旋挤压对竹纤维没有造成明显的损伤;碱性过氧化氢(AP)预浸渍可以显著降低磨浆电耗,在加拿大游离度300 mL时,该方法比烧碱(AA)法节电18.0%,并且其化机浆的结合强度较高;AA法浆料的松厚度最高、强度较差;碱性亚硫酸钠(AS)法化机浆的松厚度和强度性能介于AP和AA之间;在H2O2用量为8%的漂白条件下,AP、AS和AA预浸渍法的最佳碱用量分别为4.5%、4.5%和3.5%,同时AP预浸渍可以改善漂白效率,漂后浆白度可达56.8%(ISO),而AA预浸渍化机浆漂白浆白度仅为49.9%(ISO)。 相似文献
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景晓渝 《化工自动化及仪表》2008,35(6)
APMP是20世纪90年代开发的新浆种,它有较多的优点,如得率高、强度大、污染低等,因而与其它制浆方法相比具有较强的竞争力。介绍碱性过氧化氢化机浆的制浆(APMP)机理,论述了对制浆技术的研究情况和APMP制浆在国内的应用情况及存在的问题。 相似文献
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研究了不同碱对竹浆氧脱木素的影响,结果表明,不同碱对脱木素的影响为:NaOH>Na2CO3>NH4OH>NaHCO3;不同碱对氧脱木素纸浆粘度的影响为:NaOH>Na2CO3>NH4OH>NaHCO3;不同碱对氧脱木素纸浆白度的影响为:NaOH>Na2CO3>NaHCO3>NH4OH;不同碱对纤维素单元剪切系数(SFCU)的影响为:NaOH>Na2CO3>NH4OH>NaHCO3。 相似文献
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采用绿液蒸煮与氧脱木素联合制浆工艺对稻草原料绿液法制浆进行了初步探索。研究结果表明,稻草原料采用绿液蒸煮,在用碱量16%(Na2O计)、硫化度20%左右、最高温度150℃和不保温的蒸煮条件下,可得到卡伯值26的浆料。该浆料继续氧脱木素,在氢氧化钠用量2%~3%、氧压0.7 MPa、最高温度110℃条件下,可将卡伯值降至10左右。绿液蒸煮浆料得率可达60%以上,氧脱木素段得率约90%,联合制浆得率55%以上。绿液与氧脱木素联合制浆工艺可将麦草原料中约65%~75%的硅保留在浆料中,并且浆料的强度性能与常规碱法浆相近。 相似文献
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亚硫酸盐―甲醛―蒽醌(SFP-AQ)法是适合于草类原料的一种制浆方法。文章研究了氧脱木质素对稻草SFP浆的卡伯值、白度、粘度及强度性能的影响。结果表明,较高的用碱量有助于残余木质素的脱除,在合适的工艺条件下,稻草SFP浆单段氧脱木质素的脱木质素率可达50%以上。在氧脱木质素用碱量3.5%、氧压0.4 MPa、温度110℃、时间60 min或90 min的条件下,稻草SFP浆的卡伯值较低、白度较高,而同时具有良好的粘度和强度性能。 相似文献
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Nabil M. Safy El-Din 《Polymer International》1993,32(1):13-17
The extent of swelling of refined and unrefined cotton linter, viscose pulp and paper pulp treated with various concentrations of NaOH from 4 to 20% at 20°C, then washed with water and never dried was measured in terms of the water retention values (WRV). The treatment of unrefined fibers with alkali resulted in increase in WRV; the only exception was viscose pulp treated with 12 and 14% NaOH. Cotton pulp refined with 5% NaOH showed an increase in the swelling ability in water which increased with the concentration of alkali treatment, whereas for viscose and paper pulps the amount of water retained increased with alkali concentration up to 12% and 14% NaOH, respectively, then decreased with further increase in alkali concentration. For cotton and viscose pulps refined with 20% NaOH, the alkali treatment increased the affinity of fibers to water up to alkali concentrations of 16% and 12% NaOH, respectively,′ then the WRV became more or less stable after treatment with higher concentrations of NaOH. On the other hand, the paper pulp refined with 20% NaOH then treated with alkali concentrations from 10 to 20% showed decreased WRV. 相似文献
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利用碱性物质与H2O2在适当加热条件下能够发生剧烈反应并释放热能的原理,研究了NaOH和KOH两种制浆工艺对黑液性质和纸浆性能的影响。通过考察碱用量、H2O2用量、投料间隔时间及蒸煮时间对黑液的COD、色度及纸浆的高锰酸钾值、白度和得浆率等的影响,确定了草浆造纸清洁制浆最佳工艺条件。结果表明,NaOH制浆的最佳工艺条件为:NaOH用量11%(所述药品为100%含量,用量指占稻草原料质量的比例,下同)、H2O2用量18%、投料间隔1 h、蒸煮时间2.5 h;KOH制浆的最佳工艺条件为:KOH用量10%、H2O2用量18%、投料间隔30 min、蒸煮时间2 h。对比两种工艺所得纸浆及其产生黑液的性质,表明KOH清洁制浆效果明显优于NaOH。 相似文献
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M. A. El-Taraboulsi M. M. Nassar E. A. Abd El-Rehim 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1983,33(8):387-396
Pulping of bagasse by a rapid and mild nitric acid process was successfully carried out to produce different grades of pulp. Nitric chemimechanical bagasse pulp was produced in a high yield of 91 % on pulping depithed bagasse with 4% HNO3 for a period of 30 min at 80°C, followed by alkali pulping with 2% NaOH at 95°C for 30 min. The pulp had a satisfactory strength and high opacity. On increasing the strengths of nitric acid to 7% and alkali to 7% a nitric semichemical pulp of 65% yield was obtained. The pulp had a superior strength and high opacity. The pulp was easily bleached to 71% general electric brightness (GE) with the chlorination-alkali-extraction-hypochlorite (CEH) sequence. With 15% HNO3 and 8% NaOH, nitric chemical bagasse pulp was produced. The pulp was easily bleached to a high brightness of 82% GE with one stage hypochlorite. The pulp had a higher strength than kraft bagasse pulp. A satisfactory newsprint paper was produced on an experimental paper machine with a furnish composed of 80% bleached nitric semichemical bagasse pulp, 10% bleached softwood pulp and 10% clay. 相似文献
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膜技术处理碱法草浆黑液及综合利用技术 总被引:6,自引:0,他引:6
通过膜分离技术处理碱法草浆黑液并回收碱的试验,探索造纸黑液处理的新工艺,以求找到一种碱法草浆黑液治理的新方法,取代投资高、能耗大的燃烧法碱回收工艺。该试验结果表明:通过混凝沉淀、膜分离处理过程,黑液中CODCr和色度去除率可达96.8%和99.3%,碱回用率可达78.2%。 相似文献
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麦草绿液和氧脱木素联合制浆工艺研究 总被引:1,自引:1,他引:0
采用绿液蒸煮和氧脱木素联合制浆工艺对麦草原料绿液法制浆进行了初步探索。研究结果表明,麦草原料采用绿液蒸煮,在用碱量16%~20%、硫化度30%左右、最高温度150~170℃和短保温的蒸煮条件下,可得到卡伯值40~50的浆料,该浆料继续进行氧脱木素,在氢氧化钠用量4%~5%、0.5 MPa的氧脱木素条件下,可将卡伯值降至10左右。蒸煮段浆料得率约45%~50%,氧脱木素段得率约90%。绿液与氧脱木素联合制浆工艺可将麦草原料中约30%的硅保留在浆料中,并且浆料的强度性能与常规碱法浆相近。 相似文献
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The alkali pretreatments of cotton linters, bagasse dissolving pulp, and bagasse kraft pulp increased the accessibility of the cellulose hydroxy groups to acetylating molecules. The pretreatment with hot alkali resulted in a higher degree of esterification than with cold alkali. The filterabilities of cellulose acetates obtained from alkali pretreated samples of cotton linters, dissolving pulp, and kraft pulp were better than in case of the untreated samples. Hot refining resulted in better filterability than cold refining, but resulted in stronger degradation and lower thermal stability than cold refining. The presence of hemicelluloses in the untreated pulp lowered the reactivity towards acetylation but favoured the reactivity towards xanthation. In case of cotton linters both reactivities were improved by the alkaline pretreatments. The increase in reactivity resulting from the depolymerization of the cellulose overcame the increase in inaccessibility resulting from drying after the alkaline treatment. The removal of hemicelluloses from the dissolving and kraft pulps by alkaline extraction deteriorated the reactivities towards xanthation, but had a favourable effect on the reactivity towards acetylation. 相似文献
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对不同碱用量两段预浸渍麦草化学机械制浆(CTMP)废水的污染特征进行分析,探讨了制浆得率与污染负荷之间的关系。研究表明:采用两段NaOH浸渍,当碱总用量为3%~5%时,可以在较低的磨浆能耗得到质量指标良好的纸浆,制浆得率为73.1%~78.9%,产生的化学需氧量(COD)为270.5~446.0 kg/t,5日生化需氧量(BOD5)为181.3~228.2 kg/t,悬浮物(SS)为47.62~124.30 kg/t。此麦草CTMP制浆废水的BOD5/COD值在0.422~0.466之间,属于可生化性较好的有机废水,且mBOD5:mN:mP的结果表明采用厌氧+好氧的生化处理,反应体系的N元素和P元素均可满足微生物的需要,无需另外补充。且随着碱总用量的增加,麦草CTMP制浆得率下降,而其相应的污染负荷随之增加。在碱总用量为0~8%时,COD污染发生量(L)与制浆得率(Y)关系方程式为L=5 884-11 670Y+5 800Y2,R2=0.995。 相似文献