【作者】 曾健；

【导师】 陈克复；

【作者基本信息】 华南理工大学 ， 制浆造纸工程， 2010， 博士

【摘要】 非木浆是我国主要的造纸原料,其中麦草浆、芦苇浆、蔗渣浆占非木浆总量的80%以上,国内多数非木浆厂仍采用传统的含氯漂白方法,漂白废水很难处理。2008年颁布的《制浆造纸工业水污染物排放标准》（GB3544-2008）已经开始执行,现有的非木浆厂和新建的非木浆厂必须进行技术改造和采用新技术,否则将很难适应。本论文对麦草、蔗渣原料的清洁制浆漂白特性和机理进行了深入研究,以期为麦草、蔗渣等非木纤维资源的有效利用提供理论和技术支持。对麦草浆进行了HP短序漂白的研究。结果表明,kappa值较低的麦草浆、在HP漂白中表现出较好的可漂性,经4%～5%的次氯酸盐用量和3%～4% H2O2用量可漂至78%ISO以上,有些可达80%ISO以上,且漂后浆物理性能较好,HP漂白可取代传统的CEH漂白。对（实验室蒸煮）麦草Soda-AQ浆的OQPo漂白进行了研究。结果表明,Q预处理段的pH值对后续的漂白影响很大,pH<3.5时,Q预处理能够有效地控制浆中的金属离子分布并降低纸浆的卡伯值,为后续漂白提供有利条件。在压力H2O2漂白中,加压时间40min已经足够,纸浆的白度已达到81.59%ISO,此时纸浆的粘度为653.0mL/g。对（造纸企业提供）碱法麦草浆进行了OQPO漂白的研究,实验结果表明,优化实验得出氧脱木素段2%NaOH用量较好,适宜的氧气压力为0.5MPa,过氧化氢段4% H2O2用量已足够,终漂浆的物理性能较好。对Soda-AQ麦草浆采用D0EpD1漂白,4%的有效氯用量可将麦草浆漂至89.03%ISO,麦草终漂浆粘度为1006.5mL/g,粘度损失仅86.8 mL/g,D0EpD1漂白流程对麦草浆纤维的降解较小。蔗渣浆的单段压力过氧化氢漂白过程中,漂白温度是第一影响因素,其次是漂白时间。对于压力过氧化氢漂白蔗渣浆,综合考虑蔗渣终漂浆的白度、得率、粘度等指标,选出适合压力过氧化氢漂白蔗渣浆的工艺条件为:浆浓10%,温度90℃,时间80min,压力0.6MPa, NaOH0.4%,EDTA0.1%,Na₂SiO₃3%,MgSO₄0.5%,NaOH0.4%;在此漂白条件下,蔗渣终漂浆的白度为83.2%ISO,得率93.57%,Kappa值4.23,粘度为879.4 mL/g。研究了纸浆漂前螯合预处理的pH值、浆浓及EDTA的添加对金属离子去除的影响。结果表明,螯合预处理的pH值对过渡金属离子的脱除率存在着相应的定量关系,EDTA在酸性条件下添加有助于过渡金属离子的脱除,螯合预处理的浆浓对后续的压力H2O2漂白有一定的影响。OQPO各段漂白废水GC-MS的检测结果说明, OQPO各段漂白废水中无AOX,漂白废水中的有机物大多数为纸浆中木素和碳水化合物的降解产物,还有一部分为麦草生长过程中本身所生成的有机物质的溶出,漂白废水中的有机物都为无毒物质。OQPO各段漂白废水污染物的检测结果表明,O段和PO段废水中有机物的含量较Q段高,故其废水中的污染负荷比较大。由于氧脱木素段废水全部进入碱回收系统以及PO段废水的回用,只对Q段废水进行处理排放,Q段废水的污染负荷比较低,CODCr和BOD5分别为167mg/L和56mg/L,Q段的废水比较容易处理。HP漂白、OHP漂白、D0EpD1（ECF）漂白和OQPO（TCF）漂白,其漂白化学药品成本差别不大,TCF漂白与ECF漂白最低综合成本差别不大,但TCF漂白和ECF漂白的最低综合成本均比传统CEH漂白高出约30元/t浆。非木浆清洁漂白技术中,少污染漂白（HP、OHP）、ECF漂白和TCF漂白各有其特点,HP、OHP漂白有效降低漂白废水中的COD,色度以及AOX;ECF漂白纸浆的质量高,废水比较容易处理,但是设备投资成本高,废水中仍有一定量的AOX;OQPO漂白流程是非木浆清漂白的最佳选择,流程简单灵活,漂后浆质量好,设备投资少,废水中无AOX,漂白废水易处理。更多还原

【Abstract】 Non-wood pulp was the main paper-making material, wheat straw pulp, reed pulp and bagasse pulp were in non-wood pulp total 80%, most of the non-wood pulp mills in China were use the traditional CEH bleaching sequence, the bleached effluent were very diffcultly disposed. The“Discharge standard of water pollutants for pulp and paper industry”was promulgated and excuted in 2008, the exist non-wood pulp mills and the new non-wood pulp mills must use technological transformation and new technology, otherwise, it will difficult to adapt the new law. So, the pulping and bleaching properties of the wheat straw and bagasse was studied in this paper in order to release the pressure of the fiber shortage, and provide the technical support for the clean, efficient utilization of non-wood fiber resource.The studied on HP short sequence bleaching process of wheat straw pulp was carried out. The results showed that the lower kappa number wheat straw pulp were easy to bleach in HP bleaching sequence, at hypochlorite charge 4%～5% and hydrogen peroxide charge 3%～4% in HP bleaching sequence, they could bleach to 78%ISO brightness, some could bleach to 80%ISO,the physical property of the bleached pulp was well, HP bleaching sequence could be used as the substitute for the conventional CEH process.The study on OQPO bleaching （lab cooking）soda-AQ wheat straw pulp was carried out. The results showed that when the pH value of sulfuric acid and chelation（Q） pretreatment was less than 3.5, A/Q pretreatment efficiently controlled the metal ions distribution and decreased the kappa number, it played an important role in improving the bleaching efficiency of the pulp. The reaction time 40 minutes of the oxygen in the pressured hydrogen peroxide bleaching is enough, the bleaching pulp brightness is 81.59%ISO and the viscosity of the pulp is 653.0mL/g. The study on OQPO bleaching of alkaline wheat straw pulp （company provided） was carried out. The experiment results showed that the optimal NaOH charge and oxygen pressure were 4% and 0.5MPa, respectively; 4% charge of H₂O₂ in hydrogen peroxide stage was enough, the physics capability of the bleached pulp was better, the effluent of bleaching was low pollution , OQPO sequence bleached Soda-AQ wheat straw pulp accorded with the clean product require. D0EpD1 sequence bleaching Soda-AQ wheat straw pulp, the bleached pulp brightness was up to 89.03%ISO only at 4% charge of effective chlorite, and the bleached pulp viscosity was 1006.5mL/g, the viscosity of the bleached pulp only reduced 86.8 mL/g, D0EpD1 sequence did not damage the wheat straw pulp fiber too much.In the process of pressured hydrogen peroxide bleaching bagasse pulp, the bleaching temperature was the first effected factor, and the bleaching time was the second effected factor. Take all factors （bleached pulp brightness, yield and viscosity） into consideration, the conditions of hydrogen peroxide bleaching were as follows: pulp concentration 10%, temperature 90℃, reaction time 80 minutes, the oxygen pressure was 0.6MPa, EDTA0.1%, Na₂SiO₃ 3%, MgSO₄ 0.5%, NaOH 0.4%, H₂O₂ 4%. In this conditions, the bleached bagasse pulp brightness was 83.2%ISO, yield was 93.57%ISO, kappa number was 4.23, and the viscosity was 879.4mL/g.The studied on the pH value, pulp consistency and added EDTA in chelation pretreatment effected on removed metal ions was carried out. The results showed that the pH value in chelation pretreatment had the quantitative relationship with the removed rate of transition metal ions. EDTA was helped to remove transition metal ions in acid condition. The pulp consistency of the chelation stage was effected the pressured hydrogen peroxide bleaching.The studied on OQPO bleached effluent by GC-MS was carried out. The results showed that there are not AOX in the bleached effluent, the most of organic matter in the waste water was the degradation product of the ligin and carbohydrate, and some of the dissolved out organic matter was inborned in the wheat straw process of growth, there are not toxic substance in the OQPO bleached water.The detect of contamination results of the OQPO bleached waste water showed there are more organic matter in the oxygen delignification stage and the pressured hydrogen peroxide stage than the chleation pretreatment stage, and the pollution load is higher. The waste water in the oxygen delignification stage are all back in the akali recovery system, and the waste water in the PO stage are all reused, so only the Q stage waste water are discharge, the Q stage waste water CODCr and BOD5 are 167mg/L and 56mg/L,the effluent is low pollution load and easy to process.The bleaching sequences HP, OHP, D0EpD1（ECF） and the OQPO（TCF）, the chemical cost are almost the same, the ECF bleaching and the TCF bleaching integrated cost are not too much difference, and it higher 30 yuan per ton pulp than the CEH bleaching. The clean bleaching technology: low pollution bleaching （HP, OHP）, ECF bleaching and TCF bleaching have their own characteristic, HP and OHP bleaching effective reduced the waste water COD, chroma and AOX; ECF bleached pulp has high quality and the waste water is easy to process, but the equipment investment is high and the waste water still contain AOX; OQPO sequence is the best choice for the non-wood pulp bleaching, this sequence is simple and flexible, the bleached pulp is good, equipment investment is less than ECF bleaching, OQPO bleached waste water is easy to process and there is no AOX in the waste water.更多还原