昆明市饮用水中卤代烃现状及成因研究

本文对昆明市饮用水经加氯消毒前后卤代烃污染物进行了两的的调查，结果表明昆明市饮用水中的主要卤代烃污染物是氯仿和四氯化碳两种，其浓度均远远低于国家标准。采用传统的煮混法即可去除80％以上的污染物。     

紫外线消毒技术在污水处理中的应用

介绍了紫外消毒的机理、影响紫外消毒的因素以及紫外消毒装置的基本结构形式。阐述了紫外消毒的现状和应用前景 ,提出紫外消毒可能取代传统的化学消毒法 ,在污水处理 ,特别是回用水的处理中得到广泛的应用。     

水中有机成分及其对饮用水质的影响

微量有机污染物和氯化消毒副产物对饮用水构成直接威胁,是饮用水中要重点控制的;天然大分子有机物对水质构成间接影响,导致胶体稳定性提高、增加药耗;藻类和代谢产物影响常规处理工艺效果,对水质产生不良影响。     

高浓度复合型聚铁硅絮凝剂PFSS和PSFS的形态分布研究

采用紫外分光光度法、逐时络合比色法和红外图谱从不同角度对高浓度聚合硫酸铁硅和聚合硅酸铁的形态分布及转化规律进行了探讨。紫外吸收表明,聚铁硅絮凝剂中主要以Fe(OH)+2、Fe2(OH)4+2等二聚体为主,而且还有三聚体或其他聚合形态的存在;逐时络合分析显示,复合型聚铁硅体系中硅形态以Si(c)为主,铁形态以Fe(a)和Fe(c)为主;红外图谱证实高浓度聚铁硅是以羟桥为主结构连接的高分子复合物,在1100cm-1附近M—OH—M的振动证明有铁羟基及其聚合态存在,且其形态区别于PFS。     

氯胺消毒对三卤甲烷类消毒副产物的控制研究

在氯消毒研究的基础上,研究氯胺对消毒副产物的控制,将氯与氨氮的比值降至5,能够使单独氯消毒所生成消毒副产物减少89%,二溴一氯甲烷也不再检出;消毒副产物的生成量与氯胺的投加量呈很好的线性关系;接触时间对消毒副产物的生成量影响很小,24 h增加缓慢;pH升高至8消毒副产物的总量比pH为7时减少82.3%,一溴二氯甲烷不再检出;氯胺代替氯消毒能够很好地控制溴代消毒副产物种类和总量.     

氯胺消毒对三卤甲烷类消毒副产物的控制研究

在氯消毒研究的基础上,研究氯胺对消毒副产物的控制,将氯与氨氮的比值降至5,能够使单独氯消毒所生成消毒副产物减少89%,二溴一氯甲烷也不再检出;消毒副产物的生成量与氯胺的投加量呈很好的线性关系;接触时间对消毒副产物的生成量影响很小,24 h增加缓慢;pH升高至8消毒副产物的总量比pH为7时减少82.3%,一溴二氯甲烷不再检出;氯胺代替氯消毒能够很好地控制溴代消毒副产物种类和总量.     

太湖水体光学特征及其对水中初级生产力的影响

对太湖梅梁湾水体实测结果表明 :在水体表面 ,UV -C的强度较小 ,只有 10 -5μE·m-2 ·s-1数量级 ;UV -B的强度随着波长的增加而呈现递增的趋势 ;UV -A的强度较强 ,达 10 -2 μE·m-2 ·s-1数量级 ,并且在水体中衰减较快 ,衰减系数 (Kd)可以达到 12 .5m-1。可见光在水体中Kd 可达 8.2m-1。在水下 0 .5m处 ,紫外线不足表面光强的 1% ,可见光是表面光强的 2 0 %左右。初级生产力在表面相对较小 ,在水下 0 .2m处最大 ,且随水深的增加而减少 ;在水体中直接测定发现 ,0 .2m处溶解氧值较高。初级生产力的这种分布是水体中紫外光与可见光共同作用的结果。     

Molecular ecological networks reveal the spatial-temporal variation of microbial communities in drinking water distribution systems

Microbial activity and regrowth in drinking water distribution systems is a major concern for water service companies. However, previous studies have focused on the microbial composition and diversity of the drinking water distribution systems(DWDSs), with little discussion on microbial molecular ecological networks(MENs) in different water supply networks.MEN analysis explores the potential microbial interaction and the impact of environmental stress, to explain the characteristics of microbial...     

南方天然水体DOM的化学分级、变化特征及三卤甲烷生成势(THMFP)特性研究

采用XAD树脂吸附法,在春季内(3～5月)连续对南方深圳水库中的水体溶解性有机物(DOM)进行化学分级表征.结果表明,天然水体DOM的总量和单个化学分级组分含量在一个季节会发生一定的波动,但总的分布特征在季节内未发生根本变化,即憎水酸(HoA)和亲水部分(HiM)浓度始终较高,而憎水碱(HoB)、憎水中性物(HoN)、弱憎水酸(WHoA)浓度则相对较低.同时,选取代表性时间点对DOM各化学分级组分进行了消毒副产物三卤甲烷生成势(THMFP)的研究,发现三卤甲烷(THMs)的主要前驱物为憎水和弱憎水有机部分,对THMFP的贡献共占约80%.进一步研究发现,憎水中性物、憎水酸、弱憎水酸的THMs生成能力较强,总体上与紫外吸收能力基本一致;但弱憎水酸表现略有不同,其SUVA(100×UV254/DOC)值并不十分突出,但三卤甲烷生成能力却明显较高,说明DOM的紫外吸收特性不能完全作为THMFP特性的替代指标.亲水物质(HiM)的SUVA值也不高,但其THMs生成能力接近憎水酸部分,值得水处理工艺研究重点关注.     

The impact of UV treatment on microbial control and DBPs formation in full-scale drinking water systems in northern China

To manage potential microbial risks and meet increasingly strict drinking water health standards, UV treatment has attracted increasing attention for use in drinking water systems in China. However, the effects of UV treatment on microbial control and disinfection by-products (DBPs) formation in real municipal drinking water systems are poorly understood. Here, we collected water samples from three real drinking water systems in Beijing and Tianjin to investigate the impacts of UV treatment on microbial control and DBP formation. We employed heterotrophic plate count (HPC), flow cytometry (FCM), quantitative PCR analysis, and high-throughput sequencing to measure microorganisms in the samples. Different trends were observed between HPC and total cell count (measured by FCM), indicating that a single indicator could not reflect the real degree of biological re-growth in drinking water distribution systems (DWDSs). A significant increase in the 16S rRNA gene concentration was observed when the UV system was stopped. Besides, the bacterial community composition was similar at the phylum level but differed markedly at the genera level among the three DWDSs. Some chlorine-resistant bacteria, including potential pathogens (e.g., Acinetobacter) showed a high relative abundance when the UV system was turned off. It can be concluded that UV treatment can mitigate microbial re-growth to some extent. Finally, UV treatment had a limited influence on the formation of DBPs, including trihalomethanes, haloacetic acids, and nitrogenated DBPs. The findings of this study may help to understand the performance of UV treatment in real drinking water systems.