ON THE BLACK LIQUOR AND RECYCLE COOKING OF AS-AQ STRAW PULP

1.INTRODUCTIONAs a kind of agriculture residues, straw occupies an important status in the non-wood papermaking material in China. Straw is herbaceous plant yearly, and composed with successive and organized cell groups that is similar with others plants. The construction of straw fiber has three obvious layers and the sequence is lamella, primary wall and second wall. Because the organization is loosen andporous, the lignin content is lower and the cooking liquor is easer to penetrate so…     

THREE-PHASE CIRCULATING FLUIDIZED BED EVAPORATOR FOR WHEAT STRAW BLACK LIQUOR EVAPORATION

1.INTRODUCTIONWheat straw is the main raw material for paper-making in northern China, and its black liquor is blamed for contributing serious pollutions to the environment[1]. A technical breakthrough has been achieved in the field of chemical recovery for wheat straw pulping after more than twenty years' developments and practices. Wheat straw pulp chemical recovery projects with the pulping capacity of 75~100t/d have been put into production gradually in recent years. Evaporation of …     

烟曲霉JX-5对造纸黑液的处理研究

研究了烟曲霉JX-5对草浆造纸黑液废水的处理效果,考察了黑液废水浓度、温度、pH值、搅拌速度对黑液脱色、COD及木质素去除率的影响.研究表明,烟曲霉(Aspergillus fumigatuus)可有效处理黑液废水.最佳工艺条件下,COD和木质素去除率分别为87.13%和82.59%,脱色率为93.15%.     

氧气加压热处理降低麦草碱法蒸煮黑液黏度的技术

为了降低黑液黏度,对麦草碱法蒸煮黑液进行单纯热处理正交试验和氧气加压热处理正交试验,分析了用碱量、加热温度、保温时间及氧压对黑液黏度的影响。结果表明:氧气加压热处理比单纯热处理更能够有效降低黑液黏度,尤其当黑液质量分数大于30%时黏度降低得更加明显。相对于单纯热处理,氧气加压热处理能使得黑液浓缩的临界浓度提高5%左右。影响黑液氧气加压热处理降黏的最大因素是温度,并且得到较为适宜的降黏工艺条件为:用碱量(以NaOH计,质量分数)1.0%,温度170℃,保温时间45 min,氧压0.7 MPa。     

THE SHEAR-THINNING PHENOMENON OF BAGASSE KRAFT BLACK LIQUOR FLUID

INTRODUCTIONKraft black liquor composition is very complicated. Generally, it is a complex and multiphase fluid, which consists of organic and inorganic components. The total solids content in black liquors has a great effect on its fluidity and deformation. To the wood black liquor, there have already been detailed researches on their flow properties and many theoretic or practical results have been concluded in the literatures [1-8]. But to non-wood black liquor, the previous researches…     

隔膜电解法处理草浆黑液

进行了隔膜电解法处理草浆黑液的可行性实验研究．隔膜电解法实验采用铸铁作牺牲阳极,石墨作阴极,多孔性的滤过式隔膜将阳极区与阴极区分开;阳极及其附近有铁的氧化与水解反应,碱木素的取代反应;阴极有析氢反应;水分子和钠离子在势场力作用下透过隔膜从阳极区进入阴极区,碱木素分子被隔离在阳极区;阳极区不断加入黑液,取走木素沉淀,阴极区不断取走回收碱液,从而实现碱液与木素的分离．在电流为1A、电压为8V及室温条件下电解12h,阳极区黑液的色度、悬浮物及COD的去除率分别为66.4%,75.3%和94%,碱回收率达到94%以上．实验结果表明,作为一种处理黑液的碱回收技术,隔膜电解法处理草浆黑液比较容易直接嫁接到制浆工艺中,有可能成为解决草浆碱回收技术的新途径．     

ANALYSIS ON COMPOSITION OF FOULANTS FROM ALKALINE WHEAT STRAW BLACK LIQUOR AND DISCUSSION ON ITS FOR MING MECHANISM

1.INTRODUCTIONWheat straw is the main raw material in northern China, and its black liquor is blamed for contributing serious pollution to the environment. A technical breakthrough has been achieved in the field of chemical recovery for wheat straw pulping after more than twenty years' developments and practices. Wheat straw pulp chemical recovery projects with the pulping capacity of 75-100t/d have been put into 132--production gradually in recent years. Evaporation of wheat straw pulp…     

改性造纸黑液中SiO2对冶金炉料高温稳定性影响的研究

在利用造纸黑液中木质素合成耐火材料粘接剂的过程中，黑液中SiO2及其它有机物的存在可以改善耐火材料的高温性能及力学性能，这主要是受生成SiC多少的影响，红外图谱表明，材料的内外部SiC的生成量的多少明显存在差异，其又受生成SiC的中间过渡相SiO(g)及其它气体的多少与扩散速度所决定。     

超临界流体传热特性研究综述

 超临界状态下流体状态介于液态和气态之间,其扩散性更接近气体,密度依然为液体量级,这种特殊的性质导致超临界压力下流体流动换热特性与亚临界压力下有很大不同.本文以超临界压力条件下水、二氧化碳和碳氢燃料为研究对象,综合分析了超临界流体在管内的换热规律,系统总结了浮升力、热流密度、质量流速、压力、进口温度、流道形状等因素对流动换热特性的影响.其中,浮升力、热流密度和质量流速影响作用较大,在较高热流密度条件下,浮升力会导致传热恶化发生;在较低热流密度下,流体临界点附近会发生传热强化;质量流速增加能够使管内换热效果显著增强.传热强化和传热恶化现象的发生与临界点附近流体物性的剧烈变化密切相关.     

黑液除硅的模型试验

根据三因子二次回归正交设计试验,建立了草浆黑液的除硅模型,使用所筛选的除硅剂处理黑液,验证了模型,得到有用结论。     

H2O2-Fe2+氧化法处理棉浆泊黑液

先用酸析法对棉浆泊黑液进行预处理 ,然后用 H2 O2 -Fe2 + 法进行催化氧化。文章研究了 H2 O2 投加量及投加方式、F e2 + 投加量、反应时间和 p H对处理效果的影响。结果表明在适宜的条件下 ,废水的 COD和色度去除率分别可达 94.1%和88% ,出水用石灰乳中和后可直接排放     

麦草硫酸盐浆黑液中酚类化合物的GC测定

本文主要从环境的角度讨论了麦草硫酸盐浆黑液中主要有毒成份之一酚类化合物的GC测定方法和测定结果对环境的影响。使用国产气相色谱仪SP-2308型(北京分析仪器厂产品)、FID检测器、SP-2250气相色谱固定液的玻璃填充柱能够有效地分离17种取代酚,从麦草硫酸盐浆黑液中定性出10种取代酚,并以GC/MS结果验证。用内标法定量了其中8种取代酚。样品的预处理采用酸化、过滤、萃取、萃取剂浓缩等步骤,相对于目前国内外同类型测定方法较简便、易行。     

Recovery of Excessive NH_3 in Black Liquor from NH_4OH-KOH Pulping of Wheat Straw

Aqueous ammonia mixed with caustic potash as wheat straw pulping liquor was investigated.The caustic potash not only reduced the NH3 usage and cooking time,but also provided a potassium source as a fertilizer in the black liquor.Excessive NH3 in black liquor from wheat straw NH4OH-KOH pulping process was recovered by batch distillation with a 98% recovery rate of free NH3 under atmospheric pressure and constant reflux.The temperature at the bottom of the column was controlled at 104-105℃.After removal of free NH3,the black liquor contained 8.4 g/L NH3-N and 7.04 g/L total potassium,with a substantial amount of ammoniacal lignin,and it could be used as a liquid fertilizer for farming.The height equivalent to a theoretical plate (HETP) of a rectifier for recovering free NH3 was calculated.The diameter and height of packing of the rectifier based on a daily consumption of 75 t oven-dry wheat straw were estimated.     

造纸黑液酸化及木质素沉降研究

本文研究了ＣＯ_２在造纸工业中，对草浆黑液的酸化、木质素沉降及分离的最佳工艺条件，得到了有价值的结论。     

稻麦草氨法制浆工艺研究

研究了在氨水中添加少量钾碱作为蒸煮剂的稳麦草制浆新工艺，讨论了蒸煮剂的用量和配比，液固比，蒸煮最高温度，升温时间和保温时间对蒸煮效果的影响，继而确定了适宜的工艺条件，结果表明，该蒸煮体系对稻，麦草木素的脱除率达到85%。纸浆得率为稻草38.12%(细浆得率）和麦草49.65%(粗浆得率）。通过红外光谱（IR）测定了稻草蒸煮过程中木质素的结构变化。     

MICROBIAL STRENGTHEN OF COTTON PULP BLACK LIQUOR ANAEROBIC TREATMENT AND BMP MEASUREMENT

1INTRODUCTIONCotton pulp black liquor is regarded as a serious pollutant source in the paper-making industry. Major treatment of paper-making wastewater is aerobic process, such as activated sludge or biological filters, but most of these treatments can only be applied to the wastewater whose BOD5 is less then 800mg/L, therefore can not be used to dispose cotton pulp black liquor due to its characteristic such as dark color, rank smell, high alkali composition, complex organic pollutant…     

麦草浆黑液石灰法除硅试验研究

根据麦草浆黑液石灰法除硅的原理,通过试验研究证实,稀黑液蒸发浓缩后,加入除硅剂Ca（OH）2并充分混合,在一定温度下进行灼烧反应,无需进一步苛化,除硅率和碱回收率便可得到良好的效果,使黑液硅含量降低95%以上,碱回收率也可达到95%左右,大大缓解了碱回收工艺流程中的硅积累现象。     

利用造纸与磷肥废液调控普钙质量的方法

本文提出解决纸浆黑液与氟盐废液的污染及湿法生产普钙的水分超标等生产实际问题的设想,并引用模拟实验和工业化生产结果证实设想的可行性。     

酸化草浆黑液的粘度与结构

研究了酸对草浆黑液粘度的影响和机理。报道了黑液凝胶的形成条件、结构和性质。提出了一种固液分离方法     

NEW MANUFACTURING STUDY OF LINERBOARD MATERIALS

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 …