【作者】 刘顺明；

【导师】 陈嘉川； 臧立华；

【作者基本信息】 山东轻工业学院 ， 制浆造纸工程， 2010， 硕士

【摘要】 我国麦草纤维资源十分丰富,价格低廉,是我国造纸工业的重要原料之一。但是麦草制浆的污染也是相当的严重,本论文的目的主要是优化以麦草为原料的制浆造纸技术和对麦草制浆造纸过程产生的水污染进行治理。通过对麦草P-RC APMP制浆工艺的研究,探讨了最佳的预处理工艺条件,并对浆料进行了纤维质量分析和电镜分析。对中段水采用了絮凝预处理-IC厌氧-BAF好氧-微絮凝的深度处理方法,最终出水达到了很好的出水水质。研究了造纸深度处理水回用于洗草、挤压疏解、蒸煮、磨浆等制浆工段对成浆白度性能以及强度指标的影响,并确定了最佳回用次数以及最优回用比例。对麦草P-RC APMP制浆的预处理条件进行了研究,包括备料类型、浸泡水的温度和挤压疏解。研究结果显示,提高浸泡水的温度,可以提高成浆的白度性能与强度性能。经过挤压疏解后的纸浆的性能要好于未经挤压疏解的纸浆。通过FQA和ESEM分析研究发现,经热水浸泡和挤压疏解处理后的Ln、Lw、Lww均增加,细小组分含量减少,纤维表面凹陷、柔软、松弛,碎片减少,纤维本身没有受到过分的降解、断裂,增加了比表面积,促进了纤维的粘结。试验了不同无机絮凝剂对麦草P-RC APMP制浆产生的中段水的絮凝处理,包括Al₂（SO₄）₃、FeSO₄、Fe₂（SO₄）₃、PAC、AlCl₃、FeCl₃,研究结果发现,Fe₂（SO₄）₃对此类废水的效果最好,而且其成本也比较低,可以选择添加的量Fe₂（SO₄）₃为150～200 mg·L^-1,絮凝出水水质为pH为6.51,出水COD为2000 mg·L^-1,出水BOD5为590 mg·L^-1,出水SS为308 mg·L^-1,出水色度为300倍。对经过预处理后的水进行了模拟IC厌氧反应器的处理,研究结果显示,IC厌氧反应器对此类废水有着很好的去除效率,最终IC厌氧出水为pH为6.5,COD为580 mg·L^-1,BOD5为175 mg·L^-1,色度为200倍,SS为153 mg·L^-1。对厌氧出水进行了BAF好氧反应器的处理,研究结果显示,BAF对厌氧出水有着很好的去除效率,出水COD可以达到150 mg·L^-1,SS为34 mg·L^-1,色度为50倍,pH值为7.4。对BAF出水进行了脱色与进一步降低COD的处理,研究结果显示,Al₂（SO₄）₃与PAM连用,可以明显加快絮凝物质的沉降速度,提高出水水质。反应时间缩短为5 min,出水水质可以达到:pH为6.5,COD为50 mg·L^-1,色度为12倍,SS为8 mg·L^-1,浊度为10NTU。利用Al2（SO₄）₃与PAM联合深度处理麦草化机浆废水是可行的,具有适应性强、投资少、操作管理方便、运行简单、投资省、效果好的特点,其处理后的水质完全可以超过现行的废水水质国家排放标准。对深度处理后的出水进行了回用于不同制浆工段以及最佳回用比例的研究,包括洗草、预处理、挤压疏解、磨浆和洗浆工段。研究结果显示,废水经深度处理后回用于洗草工段,对制浆的白度性能和强度指标基本没有影响;但是不能全部回用于制浆工段,水全部回用会造成纸张白度下降,强度指标下降,会引起盐分累积,废水各项污染指标上升等不利影响,回用水的比例只能占到60%,可以认为使用回用水对浆的质量无明显的不良影响。更多还原

【Abstract】 Wheat straw is one of the most important papermaking materials in our country, which is very plentiful and cheap. However, wheat straw pulping pollution is quite serious. The aims of this thesis are mainly optimizing pulping technology with wheat straw as raw material, and treating with water pollution produced in course of pulping and papermaking. Through research on craft of the wheat straw P-RC APMP, the optimum pre-treatment conditions were discussed, and wheat straw pulp fiber quality was analyzed by FQA and electron microscope. The final effluent of the middle-stages wastewater treated with deep treatment method which was composed of flocculation pretreatment, IC anaerobic treatment, BAF aerobic treatment and micro flocculation, achieved a good water quality. The influence of the deep treated water reusing for pulping stages （for example washing grass, cooking, refining, etc） on brightness and physical strength index was studied and the optimum reuse ratio and the number were ascertained.The pre-treatment conditions of wheat straw P-RC APMP pulping including stock preparation type, temperature of the soaking water and squeezing extrusion were investigated. The results showed that higher temperature of the soaking water can improve the brightness and strength properties. The performance of the pulp with squeezing extrusion was better than the pulp without squeezing extrusion. FQA and ESEM analysis found that the hot water soaking and squeezing treatment can increased the Ln, Lw, Lww of fiber, decreased fines content and debris, made fiber surface depressed, soft, slack, increased the specific surface area and promote fiber bonding and fiber by itself was not subjected to undue degradation and fracture.Effluent from the P-RC APMP pulping was treated with different inorganic flocculants, including Al₂（SO₄）₃, FeSO₄, Fe₂（SO₄）₃, PAC, AlCl₃, FeCl₃. The results showed that Fe₂（SO₄）₃ had the best effection,and its cost is relatively lower. Under the condition of the adding of Fe₂（SO₄）₃ is 150～200 mg·L^-1, the pH in effluent is 6.51,COD is 2000 mg·L^-1,BOD₅ is 590 mg·L^-1,SS is 308 mg·L^-1,chroma is 300 times.The wastewater after flocculation pretreatment was treated by imitating IC anaerobic reactor. The results showed that IC anaerobic reactor had a high removal rate of the wastewater. The pH of the final effluent was 6.5, COD was 580 mg·L^-1, BOD5 was 175 mg·L^-1, chroma was 200 times, SS was 153 mg·L^-1. The effluent subjected by IC anaerobic treatment was treated by BAF aerobic reactor. The results showed that BAF had a very good efficiency of anaerobic effluent removal, COD can reach up to 150 mg·L^-1, SS was 34 mg·L^-1, chroma was 50 times, pH was 7.4.The effluent from BAF was treated to decolorize and further to reduce the COD. The results showed that, Al₂（SO₄）₃ used in conjunctions with the PAM can significantly speed up the flocculation settling velocity and improve water quality. Reaction time shortened to 5 min. Water quality of effluent can be achieved: pH was 6.5, COD was 50 mg·L^-1, chroma was 12 times, SS was 8 mg·L^-1, turbidity was 10 NTU. Application of PAM combination with the Al2（SO₄）₃ in advanced treatment of wastewater from wheat straw pulping was feasible, which had merit of strong adaptability, low investment, easy operation and management, simple operation, good effect. The treated water can meet the current water quality of the national wastewater discharge standard.Reusing of the advanced treated water to different pulping section including washing, pre-treatment, extrusion, refining and pulp washing and the best recycling proportion were investigated. The results showed that the whiteness and intensity had little or no impact when the advanced treated wastewater recycling for washing. However, the wastewater after treatment can not be all reused. This is because entire reusing will cause reduction of the whiteness and the strength index, accumulation of salinity, increase of the indicators of water pollution. It is acknowledged that that the proportion of recycling water can only account for 60% has not distinct bad impact on quality of pulp.更多还原