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Pipe relining via in situ epoxy lining is used to remediate corroded plumbing or distribution systems. This investigation examined the effects on odour, TOC, THM formation and disinfectant demand in water exposed to epoxy-lined copper pipes used for home plumbing. The study was conducted in accordance with the Utility Quick Test, a migration/leaching method for utilities to conduct sensory analysis of materials in contact with drinking water. The test was performed using water with no disinfectant and levels of chlorine and monochloramines representative of those found in the distribution system. Panelists repeatedly and consistently described a "plastic/adhesive/putty" odour in the water from the pipes. The odour intensity remained relatively constant for each of two subsequent flushes. Water samples stored in the epoxy-lined pipes showed a significant increase in the leaching of organic compounds (as TOC), and this TOC was demonstrated to react with free chlorine to form trichloromethane. Water stored in the pipes also showed a marked increase in disinfectant demand relative to the water stored in glass control flasks. A study conducted at a full scale installation at an apartment demonstrated that after installation and regular use, the epoxy lining did not yield detectable differences in water quality. 相似文献
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Correct identification of specific tastes and odours in a water supply can be a powerful tool in identifying the cause of the problem and facilitating rapid remediation. While taste and odour identification can be achieved by laboratory testing, consumer involvement is not only worthwhile as a public education exercise but can also indicate tastes and odours to which the public do not object. Interpretation of taste and odour results is a complex process. The Australian Water Quality Centre (AWQC), based in Adelaide, South Australia, has established a flavour profile panel, trained in Flavour Profile Analysis (FPA). This group was chosen to carry out a survey of tastes and odours present in selected Australian water supplies and laboratory treated water and bottled water. The waters were also assessed by a group of untrained volunteers to simulate the responses of consumers. In two series of tests there were significant differences in responses between the groups with respect to the intensity of the tastes and odours detected. In both instances the responses by the trained group were more consistent, making interpretation of results more straightforward. In the second series of tests the panellists were also asked their personal preferences. The results showed in general the preferred waters were those with minimal taste and odour and this was generally irrespective of the type of taste and odour present. 相似文献
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Customers are sensitive to the flavour of water. Customers evaluate drinking water based on their expectations, on experiences with their usual drinking water and on experiences with alternative waters. The Philadelphia Water Department provides one example of success in developing a better understanding of customer perceptions and attitudes about tap water taste and odour. Philadelphia found that customers do communicate in ways that water utilities can understand. Water utilities can enhance that communication and collect useful data. In addition, water utilities can characterise their tap water flavour, track it for changes and correlate changes to customer complaints. 相似文献
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山西省国定贫困县农村饮水安全工程水质普查于2016年12月进行,为期40天,共普查9924处饮水工程,检测指标19项,依据《生活饮用水卫生标准》进行了水质安全评价,全省贫困县饮水安全率达82.0%,其中太原市农村饮水安全率最高(97.8%),吕梁市农村饮水安全率最低(68.5%),主要水质超标项目为氟化物、硫酸盐、总硬度、硝酸盐。针对普查出的影响水质不安全因素,本文提出了加强宣传、加大农村饮水工程资金投入力度、增加不达标指标的处理设施等建议,本次农村饮水普查唤醒了广大农村的饮水安全意识,增加了各级政府对贫困县农村饮水安全的重视力度。 相似文献
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饮用水不同类型消毒剂对分质供水管材溶蚀作用研究 总被引:10,自引:2,他引:8
在管道分质供水工程中 ,不同类型消毒剂对管材的溶蚀作用缺乏系统研究。选择三种供水管材、三种消毒剂进行对比试验的结果表明 :对于同一种管材 ,不同类型杀菌剂对浸泡水TOC ,VOCs及口感的影响没有明显差别 ,但对于不同类型管材这些指标存在明显差别。纯净水在管道中产生的这些二次污染 ,虽然不足以引起相关水质指标超标 ,但在一定程度上会影响水的口感。建议在管道分质供水设计中 ,应根据所采用的净水工艺选择合适的管材 ,保证管道分质供水的高品质 相似文献
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在某城市供水管网中,以消火栓模拟管道漏水点,利用减压阀在供水高压区进行管道压力调控,分析不同管径的管道压力变化对漏水量的影响,以及不同减压区间的漏水率降低效果。试验结果表明,压力管理是一种行之有效的漏损主动控制方法,利用减压方式供水在优化管网运行条件的同时,可以有效地减少管网漏水量;漏水量与管道压力呈指数规律变化,该指数随减压阀所安装管道的直径不同而异;降压减漏效果对相同管径的管道在高压区更有效,而对基本相同的压力降压范围,管径越大效果越明显。实际操作中采用何种减压方式及降压范围和管段须结合管网具体情况优化选择。 相似文献
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适度超前发展农村水利为北京新农村建设提供服务与保障 总被引:1,自引:1,他引:0
按照水利部关于东部地区率先基本实现水利现代化的要求,北京市从规划入手,在明确北京水务服务新农村建设的总体目标的基础上,提出了从饮水安全、乡村水环境保护、发展节水灌溉促进农业增效农民增收和基层水务管理体制改革等各方面的具体目标和措施。 相似文献
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Failure of a pipe or valve in a water distribution system causes service disruption and other inconveniences to the customers
at or downstream of the failure location. To minimize the impact of such a pipe or valve failure, it is crucial to identify
those pipes or valves whose failure will have the most severe consequences in degrading the performance of the system relative
to that of other pipes or valves. In this paper, we develop two failure analysis methodologies, Pipe-by-Pipe and Valve-by-Valve,
to prioritize the importance of pipes and valves in a water distribution system. The relative importance of individual pipes
and valves is evaluated according to the number of customers who are forced out of service as a consequence of a pipe or valve
failure. The methodologies are based on a segment-finding algorithm which defines a series of isolated pipes in the case of
pipe or valve failure. A procedure based on the Breadth First Search is also developed to find sections of pipes that are
unintentionally isolated in the isolation procedure for failed pipes. The number of unintentionally isolated customers is
included in the Pipe-by-Pipe and Valve-by-Valve analyses in order to incorporate this negative effect of unintended isolation
of pipes. The methodologies are applied to a case study of a water distribution system for which the most important pipe and
valve are identified. The results are analyzed to form a guideline for improving the system reliability. The proposed methodologies
were found to be a valuable tool for ensuring efficient operation and developing appropriate maintenance strategies, and thereby
for improving the reliability of many water distribution systems. 相似文献
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采用超滤、颗粒活性炭和紫外线消毒组合工艺对自来水进行深度处理。试验表明,对水中浊度、CODMn、UV254、细菌总数的平均去除率分别为89.8%、90.7%、96.2%和94.5%,以上各参数最终出水平均值分别为0.155NTU、0.35mg/L、0.009cm-1、0CFU/mL,达到了现行《生活饮用水卫生标准》(GB5749—2006)和《饮用净水水质标准》(CJ94—2005)的要求。因此,超滤、颗粒活性炭与紫外线消毒组合工艺用于制备直接饮用水是可行的。 相似文献
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水源切换期用户水质跟踪监测及铁稳定性分析 总被引:1,自引:0,他引:1
针对北方某市水源切换对典型地区实际给水管网铁稳定性的影响开展试验研究。选取2个小区用户各1家,对其管网出水水质进行连续10个月的跟踪监测。结果表明,在本次水源切换过程中,管网水的SO42-有较大幅度变化,平均从25 mg/L增加到75 mg/L,之后又降至45 mg/L;造成管网出水的浊度和总铁有所增加,部分监测值超出饮用水标准,最高达到6 NTU和1.2 mg/L。不同小区管道铁稳定性存在明显差异,管网水中铁含量和浊度具有一定的线性关系。分析水源切换前后不同时期管网出水水质的变化,得出SO42-与管垢铁释放有较好的相关性。 相似文献
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A J Whelton A M Dietrich G A Burlingame M Schechs S E Duncan 《Water science and technology》2007,55(5):283-291
More than 100 years of research has focused on removing acute and chronic health threats to produce safe drinking water, but limited research has focused the consequences of removing minerals that affect drinking water taste and health. This paper covers the human sense of taste, typical variations in drinking water taste, comparisons of global taste standards, the role of water chemistry and future research needs for understanding consumer preference. Results of several consumer tap and bottled water acceptability investigations conducted by the authors are presented. 相似文献
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以南水北调鹤壁段第二施工标段为例,介绍了渠道逆止阀的安装工艺,如遵循"基础开挖→回填第一层粗砂→埋置集水暗管→回填暗管周边粗砂→铺设保温板→铺设复合土工膜→安装逆止阀"的施工流程;质量控制方法,如控制逆止阀安装位置、高程、数量等。 相似文献