【作者】 陈钰；

【导师】 钟振声；

【作者基本信息】 华南理工大学 ， 应用化学， 2010， 硕士

【摘要】 我国马铃薯产业近年来发展迅速,在多地形成了产业化基地。目前全国年排放马铃薯淀粉废水800多万t(COD含量高达10000mg/l以上),由于成本投入高、气温或技术限制等原因,大量的淀粉加工废水大部分被直接排放,造成了资源的极大浪费和环境的严重污染。而随着节能减排等环保政策的限制越来越严格,如何经济有效地处理这些有机质废水成为了当务之急。本文以回收马铃薯蛋白质为首要目标,同时降低废水的COD含量,同步达到经济高效地处理废水的目的。首先模拟目前大中型加工厂普遍采用的热处理工艺,由单因素和正交实验得出:酸热法提取马铃薯蛋白质的最优工艺条件为时间2.5h,pH 5.2,此时粗蛋白沉淀量和蛋白质回收率分别为7.00 mg/mL,43.95%,废水CODCr去除率为42.14%,还研究了不同干燥方法对蛋白产品扫描电镜观察到的表观形貌的影响,为后续实验提供了原料。其次,研究了利用超滤技术回收马铃薯淀粉废水中的蛋白质,就操作压力、温度、pH值等因素对超滤过程的影响以及不同化学清洗剂对超滤膜的清洗效果和清洗方案进行了研究。综合考虑各方面的因素,较理想的优化条件是:在废水的原pH值5.8,室温22℃,操作压力为0.10Mpa,此条件下蛋白质截留率为80.46%。对超滤膜清洗效果最佳的清洗剂是0.05%的碱性蛋白酶,恢复系数分别为99.55%。废水CODCr去除率达57.99%。最后,全面分析比较了两种蛋白质的理化性质和功能性质,以盐析蛋白质为参考,并采用三种方法联用测定了蛋白质样品的变性程度,还观察了它们的表观形貌,分析了它们的氨基酸组分含量,得出了以下结论:酸热蛋白的理化性质和功能性质不如盐析蛋白质和超滤蛋白质,变性程度和表观形貌破坏程度:酸热蛋白>超滤蛋白>盐析蛋白等。更多还原

【Abstract】 Potato industry has developed rapidly in recent years in China, industrialization bases have formed in so many places. At present, the amount of potato processing waste effluents is more than 8 000 000 t (COD content up to 10000mg/l)。As the high processing cost,the limit of frozen weather and technology, most of the process wastewater was discharged into rivers and reservoirs directly, which caused serious pollution and waste. With more and more strict of the policy on energy concervation and pollution reduction, it was time to deal with the wastewater economically and effectively.In this paper, recovery of potato protein is primary goal, the same time, to bring down the COD content economically and effectively.First, simulate the existing evaporation and concentration technology, by single-factor experiment and orthogonal experiment, The optimum conditions obtained were time 2.5h,pH5.2, the crude protein yield and recovery percent of protein is 7.00 mg/mL and 43.95%, respectively, ratio of COD elimination is 42.14%,however,the practical factory conditions is time 0.5h,pH4.8. Besides, also study on effect of apparent morphology of protein obtained by different drying methods, supply raw materials to the latter experiment also.Secondly, study on the use of ultrafiltration technology in the recovery of potato proteins from potato processing waste effluents, the effect by operating pressure, temperature and pH value and the cleaning of ultrafiltration membrane. Based on an overall consideration of various factors, The optimum conditions as follow: pH 5.8,temperature 22℃, pressure 0.10Mpa, the rejection of protein is 80.46%. The best cleaning agent is 0.05% of the alkaline protease (pH 9.0), the pure water flux recovery coefficient reached 99.94% by alkaline protease anti-washing. The ratio of COD elimination is 57.99%.At last, multi analyze Chemical characterization and functional properties of two potato proteins sample, refer to salting-out potato protein as reference materials, study on protein denaturation, apparent morphology and content of amino acids, the results as follow: the salting-out potato protein and ultrafiltration potato protein are superior to acid-evaporation potato protein, the level of protein denaturation and level of apparent morphology: salting-out potato protein>ultrafiltration potato protein>acid-evaporation potato protein.更多还原