共查询到20条相似文献,搜索用时 281 毫秒
1.
2.
道路雨水在城镇雨水资源化利用中拥有巨大潜力,但是其初期水质较差。作为一种雨水分流手段,初期雨水弃流装置能有效分离初期雨水和后期雨水。在分析已有弃流装置特点的基础上提出了一种新型容积-流量型雨水弃流装置,并开展了针对性设计及效果评估。结果表明:弃流装置的弃流过程与降雨过程有关,选定弃流标准为考虑2 mm路面填洼损失量后30 min降雨产生的径流量;在试验条件下,满足弃流标准的弃流管直径与降雨强度呈对数关系;弃流装置对SS的弃流效果最好,而对NH4+-N、NO3--N、TP及COD的弃流率相对较低,且装置的弃流效果与相关研究中其他类型弃流装置的效果基本一致。 相似文献
3.
4.
雨水初期弃流是雨水收集利用工程中重要的技术环节,容积型自控式雨水初期弃流装置,适用于要求自动运行、相对准确控制弃流量的雨水收集系统.使用该系统实现了初期雨水与中、后期的分流,有效地提高了回收雨水水质.控制器通过有线控制发出指令,控制延迟器,高水位信号延迟24h,控制电动阀开启,低水位信号关闭电磁阀,使雨水初期弃流装置复位.本文重点介绍延迟器控制原理,延迟时间的实现方式. 相似文献
5.
6.
利用水文学中的等流时线原理,类比自然流域地面径流的汇流过程,对城市雨水管网人工流域雨水汇流过程进行分析,得出了初期雨水弃流量在工程应用中的理论推求方法,发现现行比较常用的末端式弃流装置在雨水管网内汇流时间越长弃流效率越低,为初期雨水弃流设施设计选择提供了理论指导. 相似文献
7.
随着全球有利用水资源的日益短缺,近几十年来,越来越多的国家通过开发市政道路雨水收集利用模式,采取有效措施、因地制宜地进行雨水综合利用,提高了水资源的利用效率、本文在分析我国雨水利用现状的基础上,阐述了初期雨水的弃流与弃流装置,然后重点分析了市政道路雨水收集利用方法,最后展望了市政道路雨水利用技术的发展趋势 相似文献
8.
9.
分析了初期雨水弃流的重要性和弃流方法的选择,对雨水净化工艺进行了介绍。针对深圳华侨城欢乐海岸北区项目的实际情况,提出了初期雨水弃流的预处理方案,雨水处理采用气浮/消毒工艺,出水可作为小区绿化、景观用水。 相似文献
10.
对初期雨水径流弃流问题的探讨 总被引:1,自引:0,他引:1
《中国给水排水》2009,25(19)
采用混凝/沉淀工艺处理某高校校园的路面初期雨水径流,并对其弃流问题进行了探讨.结果表明,最佳混凝剂为聚合氯化铝(PAC),其最佳投量为20~35 mg/L;混凝/沉淀工艺对初期雨水的浊度、COD的去除率较高,均可达90%以上;不预沉的初期雨水径流的混凝/沉淀效果明显优于预沉后的;综合考虑初期雨水弃流装置的建设、运行、维护、管理等因素,建议校园或类似区域宜选择初期雨水不弃流,将收集到的全部雨水经混凝/沉淀处理后再利用. 相似文献
11.
城市初期雨水和初期冲刷问题剖析 总被引:4,自引:0,他引:4
初期雨水和初期冲刷是城市雨水径流污染控制中两个不同的重要问题,然而,目前国内对这两个问题的认识还普遍存在明显的局限性.基于1999年以来对城市雨水径流污染规律的研究,并结合国内外学者的研究成果,对初期冲刷现象及其描述方法、污染物积累输送规律等进行分析,明确提出研究、讨论初期冲刷问题首先应区分两种不同的典型条件;归纳了初期冲刷的主要影响因素,并进一步对国内外一些学者讨论初期雨水和初期冲刷问题时存在的矛盾与困惑进行剖析,澄清初期雨水与初期冲刷的不同概念,为把握其基本规律、深入研究城市径流污染规律、有针对性地制定有效控制措施提供理论和科学依据. 相似文献
12.
针对初期雨水及合流制溢流水质和水量波动大而引起的调蓄工程处理能力不足、运行能耗高及难以有效收集高负荷合流制溢流污水等问题,通过对不同时期进入调蓄工程的合流制溢流水质和水量特征的分析,结合调蓄工程处理工艺的沿程水质分析,考察了"微砂高效沉淀池+接触氧化池+D型滤池"工艺对合流制溢流的实际处理效果。结果表明,初期雨水及合流制溢流均呈水质和水量波动大、高氨氮、低COD的特征,氨氮是调蓄处理工艺出水水质达标的关键指标;同时,生化处理单元进水COD浓度低的特征不利于接触氧化池的生物挂膜,降低了工艺的实际处理能力。因此建议:(1)在接触氧化池后设置混凝加药装置,以保证出水SS和TP达标排放;(2)接触氧化池采用多点进水方式,并预留碳源投加装置;(3)增加精确曝气控制系统,实现节能降耗。 相似文献
13.
《Urban Water Journal》2013,10(1):45-55
On a 23 ha urban watershed, 10 km East of Paris, rainwater tanks have been installed on 1/3 of the private parcels to prevent stormwater sewer overflows. This paper investigates the macroscopic effect of rainwater harvesting on runoff, and thus the potential of this technique for stormwater source control. The analysis is performed using the SWMM 5 model, calibrated on rainfall- runoff measures from two measurement campaigns, before and after the equipment. The availability of two data-sets allows the authors to point out changes in the catchment's behaviour. The main findings are that: (1) catchment's evolution, mainly caused by individual land-cover modifications, produces non-stationarity of the hydrologic behaviour; (2) the rainwater tanks installed, although they affect the catchment hydrology for usual rain events, are too small and too few to prevent sewer overflows in the case of heavy rain events. 相似文献
14.
概述上海的雨水集蓄利用的实际情况和国内外的发展概况,结合实例对上海居住小区雨水综合利用技术,包括雨水的收集、处理、利用等进行分析,结论认为对上海居住小区推行雨水集蓄利用切实可行. 相似文献
15.
16.
Daniel Słyś 《Water and Environment Journal》2009,23(4):318-325
Systems for rainwater collection, storage and utilization are commonly used in many countries as sources of reduced quality water to be used in a sanitary network system of buildings and for watering, among others. In Poland, despite its potable water resources being almost the lowest in Europe, rainwater is utilized in a very limited manner. This paper presents a simulation model, as well as the results of analysis, evaluating the potential for utilizing rainwater under Polish climatic conditions, for utilizing various parameters of rainwater‐usage systems based on the precipitation data for the last decade. The economies of applying such systems in Poland are analysed, and the factors that restrict development of water catchment methods are defined. 相似文献
17.
The significance of entry routes as point and non-point sources of pesticides in small streams 总被引:5,自引:0,他引:5
In an agricultural catchment area in Germany we analyzed water samples from five entry routes for 2 insecticides. 5 fungicides and 13 herbicides. The sewage plant outlet and the emergency overflow of a sewage sewer contained only herbicides. In each farmyard runoff we found on average 24 g pesticides during application period, presumably caused by cleaning the spraying equipment. In comparison, the field runoff and the rainwater sewer contained less load, but also insecticides, fungicides and herbicides. The sewage plant caused 65.9% of the total herbicide load, the sewage sewer 19.8% and the farmyard runoff 12.8%. The farmyards also caused 83.7% of total insecticide and 83.8% of fungicide load. The total load of all entry routes is correlated with the amount of pesticides applied in the catchment area and the Ko/w value for each pesticide (mult. regress. r2: 0.82; p<0.0001; n = 14). In stream A the sewage plant caused a slight but continuous contamination by herbicides with 82% of the total load found during low-water phases. In comparison, stream B had only farmyard runoff and non-point sources, which caused high peaks of herbicide and a contamination by insecticides. Consequently, high-water phases generated 70% of the total pesticide load. 相似文献
18.
The erosion behaviour of biologically active sewer sediment deposits: observations from a laboratory study 总被引:1,自引:0,他引:1
The erosion behaviour of various fine-grained sediment deposits has been investigated in laboratory experiments. This work mainly focused on tests using sewer sediment in which strong biochemical reactions were observed during the deposit formation period. A small number of initial tests were conducted in which the deposits were made from mixtures of “clean” mineral and organic sediments. The erosion behaviour observed in these tests was compared with the erosion characteristics for sediments taken from deposits in a sewer. The impact of the biological processes on physical properties such as bulk density, water content, deposit structure and the erosive behaviour as a function of bed shear stress are quantified and discussed. Based on these observations it is believed that bio-processes weaken the strength of the in-pipe sediment deposits. A significantly weaker sediment surface layer was observed during deposition under quiescent oxygen-rich conditions. This resulted in a deposit with low shear strength which may be a cause of a first foul flush of suspended sediment when flow rates were increased. Comparison between tests with sewer sediments and the artificial representative surrogates suggested that the deposits of the later did not correctly simulate the depositional development and the resultant erosion patterns observed with the more bio-active sewer sediment. 相似文献
19.
Biodegradability of organic matter associated with sewer sediments during first flush 总被引:2,自引:0,他引:2
Ruben Sakrabani Jes Vollertsen Thorkild Hvitved-Jacobsen 《The Science of the total environment》2009,407(8):2989-2995
The high pollution load in wastewater at the beginning of a rain event is commonly known to originate from the erosion of sewer sediments due to the increased flow rate under storm weather conditions. It is essential to characterize the biodegradability of organic matter during a storm event in order to quantify the effect it can have further downstream to the receiving water via discharges from Combined Sewer Overflow (CSO). The approach is to characterize the pollutograph during first flush. The pollutograph shows the variation in COD and TSS during a first flush event. These parameters measure the quantity of organic matter present. However these parameters do not indicate detailed information on the biodegradability of the organic matter. Such detailed knowledge can be obtained by dividing the total COD into fractions with different microbial properties. To do so oxygen uptake rate (OUR) measurements on batches of wastewater have shown itself to be a versatile technique. Together with a conceptual understanding of the microbial transformation taking place, OUR measurements lead to the desired fractionation of the COD. OUR results indicated that the highest biodegradability is associated with the initial part of a storm event. The information on physical and biological processes in the sewer can be used to better manage sediment in sewers which can otherwise result in depletion of dissolved oxygen in receiving waters via discharges from CSOs. 相似文献