Water quality problems associated with intermittent water supply.
Water quality problems associated with intermittent water supply.
复制标题
与间歇供水相关的水质问题。
DOI：
--
复制
发表时间：
2003
影响因子：
2.7
通讯作者：
F. Hashwa
中科院分区：
文献类型：
--
作者：
S. Tokajian;F. Hashwa
在黎巴嫩进行了一项为期12个月的对照研究，以确定供应Naccache贝鲁特郊区约3000人口的小型网络中的细菌再生。居民区靠重力供水，每周两次从承压含水层的两口自流威尔斯井中获得氯化水。一个显着的相关性之间的浊度和水平的异养平板计数细菌（HPC）的样本中的分配网络，以及从自流威尔斯。然而，一个负的显着相关性之间的温度和HPC计数从源收集的样品中发现。一个统计学上显着增加的计数，可能是由于再生，反复建立两个采样点之间躺在一条直线分布线，但1公里的距离。在源水中检测到粪大肠菌群，但在管网中没有检测到粪大肠菌群，除非在管道破裂事件中确认大肠杆菌达到40 CFU/100 mL。然而，大肠菌群如弗氏柠檬酸杆菌、成团肠杆菌、E. cloxacin和E.主要是由于氯化不足，斯卡塔基一再与网络隔离。进行了第二项对照研究，以确定储存对家用储罐（500 L）微生物质量的影响，这些储罐有两种主要类型-镀锌铸铁和黑色聚乙烯。在两种罐型中储存7 d后，平均细菌计数显著增加。冬季和夏季之间的平均HPC/mL的显着差异。最高的计数发现4月至6月，虽然最高温度报告在夏季晚些时候。HPC/mL与pH、温度和储存时间呈正相关。
A controlled study was conducted in Lebanon over a period of 12 months to determine bacterial regrowth in a small network supplying the Beirut suburb of Naccache that had a population of about 3,000. The residential area, which is fed by gravity, is supplied twice a week with chlorinated water from two artesian wells of a confined aquifer. A significant correlation was detected between the turbidity and the levels of heterotrophic plate count bacteria (HPC) in the samples from the distribution network as well as from the artesian wells. However, a negative significant correlation was found between the temperature and the HPC count in the samples collected from the source. A statistically significant increase in counts, possibly due to regrowth, was repeatedly established between two sampling points lying on a straight distribution line but 1 km apart. Faecal coliforms were detected in the source water but none in the network except during a pipe breakage incident with confirmed Escherichia coli reaching 40 CFU/100 mL. However, coliforms such as Citrobacter freundii, Enterobacter agglomerans, E. cloacae and E. skazakii were repeatedly isolated from the network, mainly due to inadequate chlorination. A second controlled study was conducted to determine the effect of storage on the microbial quality of household storage tanks (500 L), which were of two main types - galvanized cast iron and black polyethylene. The mean bacterial count increased significantly after 7 d storage in both tank types. A significant difference was found in the mean HPC/mL between the winter and the summer. Highest counts were found April-June although the maximum temperature was reported later in the summer. A positive correlation was established between the HPC/mL and pH, temperature and storage time.