徐仲1,2,陈国桢2,苏婷2,张思源2,尤宏1,2
(1.城市水资源与水环境国家重点实验室(哈尔滨工业大学),哈尔滨 150090; 2.哈尔滨工业大学(威海) 海洋科学与技术学院,山东 威海 264209)
摘要:
为探究可以实现压载水达标排放的处理手段,建立了可以控制实现O3、UV单独处理的O3/UV复合压载水处理中试系统.以大肠杆菌和杜氏盐藻为目标微生物,MPN法计数剩余活菌数,CFDA-AM荧光染色法计数剩余活藻数,对该中试系统灭活微生物性能进行研究;N, N-二乙基对苯二胺(DPD)分光光度法测定该系统产生的总剩余氧化物(total residual oxidants, TRO)的衰减.结果表明,O3和UV具有协同作用,二者复合要优于单独处理的灭活效果.辐照度67 μW/cm2、O3投加量1.62 g/h、处理1.0 s、出水2 h后即检测不到大肠杆菌和杜氏盐藻的存在,能够满足国际海事组织关于微生物灭活标准.TRO浓度会随着时间的延长而衰减,且实验并未检测到菌和藻的复活,说明该系统具有理想的持续灭活性能.O3/UV复合压载水处理系统弥补了单一处理手段效率低的缺点,二者复合有利于降低能耗,可望成为新一代处理手段.
关键词: 压载水 臭氧 紫外 大肠杆菌 杜氏盐藻
DOI:10.11918/j.issn.0367-6234.201608031
分类号:P76
文献标识码:A
基金项目:
Establishment and performance of the O3/UV pilot-scale ballast water treatment
XU Zhong1,2,CHEN Guozhen2,SU Ting2,ZHANG Siyuan2,YOU Hong1,2
(1.State Key Laboratory of Urban Water Resource and Environment(Harbin Institute of Technology),Harbin 150090,China; 2.School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, Shandong, China)
Abstract:
To explore the treatment method that enables the quality of ballast water to meet the discharge standard, the O3/UV combined ballast water treatment system was established, in which O3 and UV can be controlled independently. Escherichia coli and Dunaliellasalina are target microorganisms. To study the system performance in inactivating microorganisms, MPN and CFDA-AM fluorescence staining were used to count residual viable bacteria and residual viable algae respectively. N, N-Diethyl-p-phenylenediamine (DPD) spectrophotometry was used to measure the attenuation of total residual oxide (TRO) generated in the system. The results show that O3 and UV have a synergistic effect, and the combination of the two has better performance of inactivation than that of the individual treatment. Under the condition of 67 μW/cm2 UV irradiance, 1.62 g/h of the O3 dosage for 1s exposure, the Escherichia coli and Dunaliellasalinacan cannot be detected after 2 h, which means the effluent can meet IMO microbial inactivation standards. TRO concentration decayed with time, and the experiment did not detect the resurrection of bacteria and algae, which indicate a good continuous inactivation performance of the system. Compared with individual treatment, the combined system increases the treatment efficiency and reduces the energy consumption, which makes itself a promising method.
Key words: ballast water ozone UV E.coli Dunaliellasalina
徐仲, 陈国桢, 苏婷, 张思源, 尤宏. 紫外/臭氧复合压载水处理系统的建立与运行[J]. 哈尔滨工业大学学报, 2018, 50(2): 100-103. DOI: 10.11918/j.issn.0367-6234.201608031.
![复制到剪切板](http://hit.alljournals.cn/html/hitxb_cn/2018/2/images/copy.gif)
XU Zhong, CHEN Guozhen, SU Ting, ZHANG Siyuan, YOU Hong. Establishment and performance of the O3/UV pilot-scale ballast water treatment[J]. Journal of Harbin Institute of Technology, 2018, 50(2): 100-103. DOI: 10.11918/j.issn.0367-6234.201608031.
![复制到剪切板](http://hit.alljournals.cn/html/hitxb_cn/2018/2/images/copy.gif)
作者简介 徐仲(1962—),男,副教授;
尤宏(1961—),男,教授,博士生导师 通信作者 尤宏,youhong@hit.edu.cn 文章历史 收稿日期: 2016-08-15
Contents -->Abstract Full text Figures/Tables PDF
紫外/臭氧复合压载水处理系统的建立与运行
徐仲1,2, 陈国桢2, 苏婷2, 张思源2, 尤宏1,2
![通讯作者](http://hit.alljournals.cn/html/hitxb_cn/2018/2/images/REcor.gif)
![youhong@hit.edu.cn](http://hit.alljournals.cn/html/hitxb_cn/2018/2/images/REemail.gif)
1. 城市水资源与水环境国家重点实验室(哈尔滨工业大学),哈尔滨 150090;
2. 哈尔滨工业大学(威海) 海洋科学与技术学院,山东 威海 264209
收稿日期: 2016-08-15
作者简介: 徐仲(1962—),男,副教授;
尤宏(1961—),男,教授,博士生导师
通信作者: 尤宏,youhong@hit.edu.cn
摘要: 为探究可以实现压载水达标排放的处理手段,建立了可以控制实现O3、UV单独处理的O3/UV复合压载水处理中试系统.以大肠杆菌和杜氏盐藻为目标微生物,MPN法计数剩余活菌数,CFDA-AM荧光染色法计数剩余活藻数,对该中试系统灭活微生物性能进行研究;N, N-二乙基对苯二胺(DPD)分光光度法测定该系统产生的总剩余氧化物(total residual oxidants, TRO)的衰减.结果表明,O3和UV具有协同作用,二者复合要优于单独处理的灭活效果.辐照度67 μW/cm2、O3投加量1.62 g/h、处理1.0 s、出水2 h后即检测不到大肠杆菌和杜氏盐藻的存在,能够满足国际海事组织关于微生物灭活标准.TRO浓度会随着时间的延长而衰减,且实验并未检测到菌和藻的复活,说明该系统具有理想的持续灭活性能.O3/UV复合压载水处理系统弥补了单一处理手段效率低的缺点,二者复合有利于降低能耗,可望成为新一代处理手段.
关键词: 压载水 臭氧 紫外 大肠杆菌 杜氏盐藻
Establishment and performance of the O3/UV pilot-scale ballast water treatment
XU Zhong1,2, CHEN Guozhen2, SU Ting2, ZHANG Siyuan2, YOU Hong1,2
![Corresponding author](http://hit.alljournals.cn/html/hitxb_cn/2018/2/images/REcor.gif)
![youhong@hit.edu.cn](http://hit.alljournals.cn/html/hitxb_cn/2018/2/images/REemail.gif)
1. State Key Laboratory of Urban Water Resource and Environment(Harbin Institute of Technology), Harbin 150090, China;
2. School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, Shandong, China
Abstract: To explore the treatment method that enables the quality of ballast water to meet the discharge standard, the O3/UV combined ballast water treatment system was established, in which O3 and UV can be controlled independently. Escherichia coli and Dunaliellasalina are target microorganisms. To study the system performance in inactivating microorganisms, MPN and CFDA-AM fluorescence staining were used to count residual viable bacteria and residual viable algae respectively. N, N-Diethyl-p-phenylenediamine (DPD) spectrophotometry was used to measure the attenuation of total residual oxide (TRO) generated in the system. The results show that O3 and UV have a synergistic effect, and the combination of the two has better performance of inactivation than that of the individual treatment. Under the condition of 67 μW/cm2 UV irradiance, 1.62 g/h of the O3 dosage for 1s exposure, the Escherichia coli and Dunaliellasalinacan cannot be detected after 2 h, which means the effluent can meet IMO microbial inactivation standards. TRO concentration decayed with time, and the experiment did not detect the resurrection of bacteria and algae, which indicate a good continuous inactivation performance of the system. Compared with individual treatment, the combined system increases the treatment efficiency and reduces the energy consumption, which makes itself a promising method.
Key words: ballast water ozone UV E.coli Dunaliellasalina
压载水在船舶航行中起到了至关重要的作用, 但由于来自不同的港口及水域, 含有大量不同种类的生物, 故压载水的远洋运输和排放可能会带来物种入侵问题, 由压载水造成的生物入侵已经成为全球环境基金组织(GEF)密切关注的重要问题之一[1].目前, 已经确认是由船舶压载水传播而来的入侵生物物种就有约500种之多.中国由压载水携带而来的赤潮微生物已有近20种, 其中包括洞刺角刺藻、新月圆柱藻等, 这会对海域原有的自然生态系统及生物群落构成威胁[2-3].2004年, 国际海事组织IMO通过了《国际船舶压载水及其沉积物管理与控制公约》, 并颁布了压载水处理设备的性能标准(即D-2排放标准), 标准中规定了压载水排放时所含不同尺寸生物允许排放的最大浓度, 大于50 μm微生物为10 cells/mL, 10~50 μm的微生物为10 cells/ mL, 霍乱弧菌、大肠杆菌、肠道球菌分别为1, 250和100 CFU/100 mL.
现有研究表明, O3对压载水有很好的处理效果, 产物无二次污染, 但单一O3处理, 达标所需O3浓度较高, 耗能较大[4]; 吴雪飞等[5]的研究表明, O3投加量为0.5~0.8 mg/L时, 叶绿素a的去除率达60%.Wright等[6]研究表明, O3法处理压载水, 投加量在2.5~7.0 mg/L时, 可达到IMO压载水排放标准.UV作用安全环保, 但对藻类灭活效果较差[7].先前的研究表明[8]紫外辐射强度为100 μW/cm2时, 检测到细菌的光复活现象, 而郭美婷等[9]的研究表明, 紫外辐射剂量越低, 对细胞的灭活作用越小.Ole Kristian等[10]发现经UV灭菌, 菌落检出数为0, 但是3 d后菌落数量恢复到处理前的水平.
由于单一处理方式存在一定的局限性, 本文在前期研究的基础上[11-12], 建立了O3/UV复合压载水处理系统, 并探究了系统的微生物灭活性能.实验表明, 该系统弥补了单一处理手段效率低的缺点, 并且有利于降低能耗.为达到IMO《公约》要求的压载水处理方法提供了新的方向和途径.
1 实验根据前期研究[12-13]建立了如图 1所示的O3/UV复合压载水处理系统.该处理系统由卧式离心泵、自清洗过滤器、臭氧发生系统和紫外辐射系统4部分组成.海水进入系统后首先经过滤器滤除50 μm以上的生物, 然后经射流混合器与臭氧混合, 进入紫外辐射单元, 在臭氧与紫外辐射复合作用下灭活剩余微生物, 出水经气液分离后进入压载舱.
Figure 1
![点击查看原图](http://hit.alljournals.cn/html/hitxb_cn/2018/2/PIC/hebgydxxb-50-2-100-1.jpg)
系统采用卧式离心泵, 额定流量8 t/h, 扬程45 m, 采用变频系统调节流量, 控制水力停留时间为1.0~3.0 s.压载水处理前端采用过滤精度为50 μm的自清洗过滤器.臭氧发生器产生的O3通过文丘里射流式扩散体系与压载水进行气液混合, 气液接触时间短, 混合效果好.O3质量浓度可变范围为0~100 g/m3, 流量变化范围为0.2~3 L/min.紫外辐射系统采用同心圆柱型反应器, 低压汞齐紫外灯置于筒体中心位置, 外套石英管, 石英管外紫外辐射强度为67 μW/ cm2.实验所用海水取自山东省威海市近海海域(东经122.14°, 北纬37.52°).其pH为8.3±0.1, 温度(20±1)℃, 原水细菌总数约(106±102)CFU/100 mL, 大肠菌群数为(40±5)CFU/100 mL.实验符合国际海事组织G8导则[14]相关规定, 以大肠杆菌作为处理菌种进行灭活实验, 菌种由哈尔滨工业大学(威海)微生物学实验室提供, 采用MPN法(GB17378.7—2007)对其进行检测; 选用杜氏盐藻作为实验微藻, 藻种由辽宁省海洋水产科学研究院提供, 采用CFDA-AM染色法用荧光显微镜(奥林巴斯BX43)进行检测.根据G8导则规定, 本实验的模拟压载水中细菌浓度为108 CFU/mL, 微藻浓度为104个/mL.出水TRO浓度采用DPD分光光度法(北京普析YU-1810S)测定[15].
2 结果与讨论本实验所用大肠杆菌和杜氏盐藻形态微小, 可忽略过滤器流速的影响.系统在单独O3作用下对微生物的灭活性能如图 2所示.
Figure 2
![点击查看原图](http://hit.alljournals.cn/html/hitxb_cn/2018/2/PIC/hebgydxxb-50-2-100-2.jpg)
在O3投加量为2.12 g/h(0.265 mg/L), 处理3 s后大肠杆菌和杜氏盐藻的灭活率分别达1.23lg和0.53lg.O3/UV复合处理的微生物灭活性能如图 3所示, 同样在O3投加量为2.12 g/h时, 处理3 s后大肠杆菌和杜氏盐藻的灭活率分别达3.02lg和1.081g, 与单独O3相比, 灭活效果显著提升.相同O3浓度, 不同反应体系的灭菌对比结果如图 4所示, O3/UV复合作用下的灭菌效果比单独UV、单独O3作用下以及模拟单独UV和O3加和的灭菌效果要好, 说明UV、O3具有一定的协同作用.这可能是因为O3在紫外光的照射下会产生过氧化物, 如H2O2、·OH等, 使反应体系中的氧化性物质种类及浓度增加[16], 从而提升了系统的整体灭菌效果.
Figure 3
![点击查看原图](http://hit.alljournals.cn/html/hitxb_cn/2018/2/PIC/hebgydxxb-50-2-100-3.jpg)
Figure 4
![点击查看原图](http://hit.alljournals.cn/html/hitxb_cn/2018/2/PIC/hebgydxxb-50-2-100-4.jpg)
根据IMO公约D-2的规定, 出水中大肠杆菌应少于250 CFU/100 mL, 根据进水菌液浓度计算得出, 在臭氧投加量2.12 g/h、紫外辐射强度67 μW/cm2条件时, 本设计的臭氧/紫外复合处理系统已满足IMO公约规定的大肠杆菌出水排放标准.
O3/UV复合后的灭藻效果提升显著, 这可能是因为O3对藻细胞内外物质的氧化[17]和UV对藻细胞DNA破坏的双重作用[18], 同时, O3在UV辐射下产生了一定的协同作用, 进一步提升了系统的整体灭藻效果.
O3/UV复合处理对微生物的持续灭活效果如图 5.O3投加量为1.62 g/h (0.202 mg/L)时, 即时出水剩余活菌数为186 CFU/mL, 出水1 h剩余活菌数为40 CFU/mL后出水后2.0 h检测不到活菌的存在; O3投加量2.12 g/h时, 即时出水剩余活菌数为144 CFU/mL, 出水1 h剩余活菌数为17 CFU/mL后出水后1.5 h检测不到活菌的存在.复合处理系统的灭藻性能很好, O3投加量1.62 g/h时, 即时出水剩余盐藻数为2 511 cells/mL, 出水后1.0 h后活藻细胞数为152 cells/mL, 出水后2.0 h无活藻细胞的存在; O3投加量2.12 g/h时, 即时出水剩余盐藻数为2 089 cells/mL, 出水后1.0 h后活藻细胞数为67 cells/mL, 出水后1.5 h无活藻细胞存在, 且5 d后均未检测到活菌和活藻.这表明O3/UV系统对微生物的持续灭活效果能够满足IMO对船舶压载水处理设备的性能需求.
Figure 5
![点击查看原图](http://hit.alljournals.cn/html/hitxb_cn/2018/2/PIC/hebgydxxb-50-2-100-5.jpg)
本实验对该系统出水TRO的测定结果如图 6所示, 出水TRO质量浓度随O3投加量增加而升高, 说明O3投加量对TRO的影响很大.出水TRO质量浓度反映压载水处理系统对微生物的持续灭作用.如图 7所示, 出水后TRO质量浓度会随着时间的延长而衰减, 在前10 h TRO衰减较快, 10 h之后衰减缓慢.同时本实验并未检测到复活现象, 可能是TRO的存在可以抑制由紫外灭菌系统产生的细胞暗修复和光复活现象[19].
Figure 6
![点击查看原图](http://hit.alljournals.cn/html/hitxb_cn/2018/2/PIC/hebgydxxb-50-2-100-6.jpg)
Figure 7
![点击查看原图](http://hit.alljournals.cn/html/hitxb_cn/2018/2/PIC/hebgydxxb-50-2-100-7.jpg)
3 结论1) 通过不同系统灭活性能考察得出, O3/UV复合处理系统的灭活效果优于两种单独处理方式, 表现出一定的协同效果, 克服了单一处理系统效率低的缺点, 降低了单独臭氧的耗量, 并且未检测到光复活的发生, 有利于降低能耗, 提高系统的效能.
2) 复合系统产生的TRO受O3影响很大, 产生的TRO衰减速度在前10 h较慢, 具有理想持续灭活性能, 在辐照度67 μW/cm2、O3投加量为1.62 g/h条件下, 处理1.0 s后的出水2 h后即检测不到大肠杆菌和杜氏盐藻的存在, 能够满足IMO对压载水中10~50 μm微生物的灭活要求.
参考文献
[1]TSOLAKI E, DIAMADOPOULOS E. Technologies for ballast water treatment: A review[J].Journal of Chemical Technology and Biotechnology, 2010, 85: 19-32.DOI: 10.1002/jctb.v85:1
[2]魏国强, 赵岩, 沙豪, 等. 船舶压舱水的危害及压舱水处理技术的现状[J].广东化工, 2011, 38(8): 71-72.
WEI Guoqiang, ZHAO Yan, SHA Hao, et al. The harmful effect of ballast water and the development of ballast water treatment[J].Guangdong Chemical Industry, 2011, 38(8): 71-72.
[3]孙玉科. 船舶压载水处理高效杀菌系统研究[D]. 镇江: 江苏科技大学, 2012: 9-10.
SUN Yuke. The study on efficient sterilization system of ships' ballast water treatment[D]. Zhenjiang: Jiangsu University of Science and Technology, 2012: 9-10.http://cdmd.cnki.com.cn/Article/CDMD-10289-1012043698.htm
[4]SAKAI H, OGUMA K, KATAYAMA H, et al. Effects of low or medium pressure ultraviolet lamp irradiation on microcystis aeruginosa and anabaena variabilis[J].Water Research, 2007, 41(1): 11-18.DOI: 10.1016/j.watres.2006.09.025
[5]吴雪飞, 严祺, 王先云, 等. 原水预臭氧工艺控藻除嗅效果分析[J].净水技术, 2016, 35(S1): 16-19.
WU Xuefei, YAN Qi, WANG Xianyun, et al. Removal of algae and 2-methylisoborneol by pre-ozonation in raw water[J].Water Purification Technology, 2016, 35(S1): 16-19.
[6]WRIGHT D A, GENSEMER R W, MITCHELMORE C L, et al. Shipboard trials of an ozone-based ballast water treatment system[J].Marine Pollution Bulletin, 2010, 60(9): 1571-1583.DOI: 10.1016/j.marpolbul.2010.04.010
[7]LU Weicai. Main techniques of ballast water treatment[J].Journal of Dalian Maritime University, 2009, 35(5): 22-25.
[8]吴东海. 臭氧/光催化高效生物灭活及在船舶压载水处理中的应用[D]. 哈尔滨: 哈尔滨工业大学, 2011.
WU Donghai. Efficient inactivation of microorganisms by photocatalytic ozonation process and its application for ballast water treatment[D]. Harbin: Harbin Institute of Technology, 2011.http://cdmd.cnki.com.cn/Article/CDMD-10213-1012000474.htm
[9]郭美婷, 胡洪营, 陈健, 等. 紫外线对铜绿微囊藻的抑制效果及特性研究[J].环境科学, 2011, 32(6): 1609-1613.
GUO Meiting, HU Hongying, CHEN Jian, et al. Inhibitory effects of ultraviolet irradiation on the growth of microcystis aeruginosa[J].Environmental Science, 2011, 32(6): 1609-1613.
[10]HESS-ERGA O K, BLOMV?GNES-BAKKE B, VADSTEIN O. Recolonization by heterotrophic bacteria after UV irradiation or ozonation of seawater:A simulation of ballast water treatment[J].Water Research, 2010, 44(18): 5439-5449.DOI: 10.1016/j.watres.2010.06.059
[11]WU Donghai, YOU Hong, ZHANG Ran, et al. Ballast waters treatment using UV/Ag-TiO2+O3 advanced oxidation process with Escherichia coli and Vibrio alginolyticus as indicator microorganisms[J].Chemical Engineering Journal, 2011, 174(2/3): 714-718.
[12]WU Donghai, YOU Hong, ZHANG Ran, et al. Inactivation of Escherichia coli using UV/Ag-TiO2/O3-mediated advanced oxidation: Implications for ballast water disinfection[J].Journal of Chemical Technology and Biotechnology, 2011, 86(12): 1521-1526.DOI: 10.1002/jctb.v86.12
[13]WU Donghai, YOU Hong, DU Jiaxuan, et al. Effects of UV/Ag-TiO2/O3 advanced oxidation on unicellular green alga Dunaliellasalina-implications for removal of invasive species from ballast water[J].Journal of Environmental Sciences, 2011, 23(3): 513-519.DOI: 10.1016/S1001-0742(10)60443-3
[14]IMO International Maritime Organization. Guidelines for approval of ballast water management systems(G8)[J].Annex 4 Resolution MEPC, 2008, 174(58): 1-30.
[15]PERRINS J C, COOPER W J, VAN L J, et al. Ozonation of seawater from different locations: Formation and decay of total residual oxidant-implications for ballast water treatment[J].Marine Pollution Bulletin, 2006, 52(9): 1023-1033.DOI: 10.1016/j.marpolbul.2006.01.007
[16]张彭义, 祝万鹏. 臭氧水处理技术进展[J].环境科学进展, 1995(6): 18-24.
ZHANG Pengyi, ZHU Wanpeng. Progress of ozonation technology in water treatment[J].Advance in Environmental Science, 1995(6): 18-24.
[17]PLUMMER J D, EDZWALD J K. Effect of ozone on disinfection by-product formation of algae[J].Water Science and Technology, 1998, 37(2): 49-55.
[18]倪福祥, 程丽华, 王希成, 等. 污水处理中的紫外消毒技术[J].青岛建筑工程学院学报, 2003, 24(2): 30-32.
NI Fuxiang, CHENG Lihua, WANG Xicheng. Ultraviolet disinfection in sewage treatment[J].Journal of Qingdao Insitute of Architecture and Engineering, 2003, 24(2): 30-32.
[19]陈操, 孟祥盈, 白敏冬, 等. 基于强电离放电技术制备羟基自由基的船舶压载水处理系统设计[J].高电压技术, 2014, 40(7): 2238-2244.
CHEN Cao, MENG Xiangying, BAI Mindong, et al. Treatment system of ballast water in oceanic ships using hydroxyl radical(·OH) based on strong electric-field discharge[J].High Voltage Engineering, 2014, 40(7): 2238-2244.