紫外+超滤组合工艺在袋装水消毒上的应用

Application of ultraviolet+ultrafiltration combined process in disinfection of bagged water

针对袋装饮用水臭氧消毒环节,臭氧因与共挤膜发生化学反应难以保证水质的问题,探讨了采用紫外+超滤的方式来代替臭氧作为终端消毒方式的可行性,以适应袋装水密闭、长久保质的特点。紫外线消毒具有广谱、高效、不产生二次污染等特点,当紫外线剂量达到12.2 mJ/cm^(2)时,菌落总数和大肠杆菌的对数灭活率达到1.5以上,而铜绿假单胞菌只有0.56;继续增大紫外线剂量到20.4 mJ/cm^(2)时,这3类微生物指标的对数灭活率都达到了2.0以上,此时的消毒灭菌效果比较理想。截留分子量6000 Da的超滤膜对微生物的去除效果明显,77 d内依次检测样品中菌落总数、大肠杆菌和铜绿假单胞菌,没有一例致不合格的复活现象,取得了良好的消毒效果,适用于实际生产。

In view of the issue that it is difficult to ensure the water quality due to the chemical reaction between ozone and coextrusion membrane in the process of ozone disinfection of bagged drinking water,the feasibility of using ultraviolet(UV)+ultrafiltration(UF)instead of ozone as the terminal disinfection method was discussed,so as to adapt to the characteristics of closed and long-term quality of bagged water.The UV disinfection has the characteristics of broad spectrum,high efficiency and no secondary contamination.When the UV dose reached 12.2 mJ/cm^(2),the logarithmic inactivation rate of the total number of colonies and Escherichia coli reached more than 1.5,while that of Pseudomonas aeruginosa was only 0.56.When the UV dose was continuously increased to 20.4 mJ/cm^(2),the logarithmic inactivation rates of these three kinds of microbial indicators were more than 2.0,obtaining an ideal disinfection and sterilization effect.The UF membrane with a molecular weight of 6000 Da had an obvious effect on microbial removal and no unqualified resurrection phenomenon was found in the sequential detection of the total number of colonies,Escherichia coli and Pseudomonas aeruginosa in the sample within 77 days,which obtained good disinfection effect and was suitable for the actual production.