Behavior of Decayed Spruce (Picea abies) during Kraft Pulping

This study indicated that by applying an improved classification system to decayed large-diameter Norway spruce (Picea abies) wood, its use as raw material for kraft pulping without loss of pulp quality could be essentially increased. This is based on the fact that although the cooking yield of decayed spruce material which has been sorted according to these new recommendations is somewhat lower and Kappa number higher than those of sound wood material, the greatest part of the decayed stem (the outer part of the stem) contains long-fiber wood material which produces pulp of good quality. Therefore, large-diameter spruce logs can also be separately used, for example, in the manufacture of reinforcement pulp.     

柠条的纤维特性及其双螺杆CMP制浆性能研究

以柠条为原料，分析了其化学组分和纤维形态，并探讨了柠条双螺杆CMP法的制浆工艺以及浆料的纤维形态和成纸的物理性能。研究结果表明：与针、阔叶木相比，柠条原料中纤维素和综纤维素质量分数较低，苯醇抽出物和热水抽出物质量分数较高，柠条纤维长度总体偏短，木质部和皮部的纤维质量平均长度分别为0.621和0.819 mm，还存在部分杂细胞。采用3.5% Na₂SO₃和1.5% NaOH常温预浸12 h、90℃汽蒸1 h后再用双螺杆挤浆机在质量分数35%下进行搓丝，并结合高浓盘磨机磨浆，所得CMP浆得率可达73%。柠条CMP浆基本保持了纤维原有的长度，质量平均长度达0.650 mm，长宽比为32.7，纤维解离较好，但分丝帚化情况不理想，含有部分纤维束和杂细胞。当加拿大游离度为300 mL时，柠条CMP浆成纸的环压强度指数和松厚度较高，分别为8.67（N·m）/g和2.56 cm³/g，抗张指数为19.6（N·m）/g，本色浆白度较高，达50%（ISO）。柠条CMP浆适合配抄瓦楞原纸等包装用纸，漂白后可配抄新闻纸和白板纸。     

三维电极法处理印染废水二级出水的试验研究

印染废水二级出水中含有难生物降解的有毒有害物质,国家和地方制定了日益严格的污染物排放标准。这就要求企业对二级出水进行深度处理,实现废水重复利用。文章以广州某印染废水处理厂的二级出水为研究对象,利用三维电极法进行CODCr去除试验,考察了电解时间、直流电压、进水pH及曝气量对CODCr去除率的影响。试验表明:三维电极法对印染废水二级出水CODCr有良好的去除效果:当电解时间为15 min、直流电压为28 V、进水pH为3.5、曝气量为一般强度时,出水CODCr浓度可从88 mg/L降低到37 mg/L,对应的去除率为57.9%。     

杨木无催化甘油法制浆工艺及其性能的研究

研究了杨木无催化甘油法制浆的主要因素对成浆状况的影响规律,同时对无催化甘油法制浆的打浆性能和成纸性能进行了初步评价,比较了无催化甘油法制浆和盘磨机械浆（RMP）性能的主要差异。结果表明：杨木无催化甘油法制浆的最佳工艺条件为反应温度210℃、反应时间60min和反应液比1：8,在此条件下浆料的粗浆得率为75．9％,细浆得率为71．4％：该方法制得浆料初始打浆度为11°SR,对应的纸张裂断长1．34km,抗张指数13．10N·m／g,耐破指数1．28kpa·m2／g,松厚度2．15cm3／g以及白度12．46％ISO;杨木无催化甘油法制得浆料比杨木RMP更易打浆,成纸的裂断长和抗张强度远高于杨木RMP,但其松厚度略低于杨木RMP。通过实验得出杨木无催化甘油法制浆具有工艺简单、得率高、易打浆及强度高等优点。     

草浆黑液的化学改性和作为混凝土减水剂的应用

采用催化氧化再磺化工艺制备了水溶性草浆黑液木质素磺酸盐(SBT-LSN)混凝土减水剂。混凝土试验结果表明,经磺化改性后的产品分散性能得到明显改善,在0.25%掺量下,混凝土减水率达11.4%,含气量为4%,有一定的缓凝作用;对混凝土抗压强度有较大的提高,3d和28d抗压强度比分别达125%和110%,对混凝土早期强度的改善更明显。其适宜的掺量范围为水泥含量的0.1%～0.5%,适合于配制C40(及以下)中低强度混凝土。     

Possibilities of the Formation of Enol-Ethers in Lignin by Soda Pulping

In the alkaline decomposition of a β-O-4 type lignin model compound (erythro-guaiacylglycerol-β-guaiacyl ether, compound 1), an isomeric pair of C₆C₂ enol-ether (2-methoxy-4-[2-(2-methoxyphenoxy)-vinyl]-phenol, compound 2) was detected as the main decomposition product with no trace of C₆C₃ enol-ether (4-[3-hydroxy-1-(2-methoxyphenoxy)-propenyl]-2-methoxy-phenol, compound 3) or other dimers. In contrast, compound 2 was not detected in the alkaline decomposition products of compound 3. Under alkaline conditions, the γ-hydroxymethyl group of compound 3 was reduced to form 2-methoxy-4-[1-(2-methoxyphenoxy)-propenyl]-phenol (compound 4). In the HSQC analysis of soda lignin, the formation of substructures of C₆C₂ type enol-ether (related to compound 2) was confirmed. However, no substructures related to compound 4, which could be formed if a substructure of C₆C₃ type enol-ether was formed under alkaline conditions, were detected. Therefore, it could be concluded that C₆C₃ type enol-ethers could not be intermediates of alkaline decomposition products of lignin.     

Modified Kraft Pulping of Bagasse: Infrared Spectroscopy of Lignin

Abstract

The infrared spectroscopy of precipitated lignin from waste black liquors of bagasse pulping with kraft sulfite pulping process was investigated. Also the effect of anthraquinon and methanol addition in the soda, kraft and kraft-sulfite pulping liquor on the infrared specra of the precipitated lignin was studied. The presence of methanol in the pulping liquor causes an increase in the degradation as well as increase in the carboxylic group in the precipitated lignin. Also, the phenolic hydroxyl group in case of kraft lignin is higher than soda lignin. Presence of sulfite in the kraft-sulfite pulping liquor produces lignin hydroxyl groups.     

烟气脱硫装置中出现的问题与解决措施

介绍了中国石油宁夏石化公司烟气脱硫装置的基本情况,重点分析了烟气浓度、制浆系统、吸收塔及石膏脱水系统出现的问题及对烟气脱硫系统的影响,并提出了一些解决方法,提高了FGD系统运行的稳定性。     

草浆造纸清洁制浆工艺研究

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。     

玉米芯酶解残渣制备混凝土减水剂的工艺研究

利用碱性亚硫酸钠对玉米芯制备生物乙醇的酶水解残渣进行磺化改性研究,获得了性能良好的木质素磺酸盐,用作混凝土减水剂。结果表明,碱性亚硫酸盐法分离木质素的适宜工艺条件为:总用碱量(按Na2O计)14%,蒸煮温度155℃,保温时间3～3.5 h,亚硫酸化度85%。在此工艺条件下木质素磺酸盐得率为51.39%,在掺量为0.35%(以固形物计)时,产品的水泥净浆流动度可达到112 mm,1%溶液表面张力为46.4 mN/m,产品磺酸基含量为1.89 mmol/g。