台州市生活污水处理厂设计水量中雨水混入比例研究

基于台州市椒江区2014年污水处理厂进水量和雨量监测站的数据,进行污水处理厂日进水量频率分析和城镇污水管网中雨水混入比例分析,从而对污水处理厂设计水量进行修正。结果表明:小雨、中雨、大雨、连续暴雨时的污水量分别是晴天污水量的1.29、1.53、1.77、2.31倍;地下水与河水渗入量约占晴天日均污水量的24.1%,雨天雨水混入量约占雨天日均污水量的24.2%;随着降雨量增大,雨水混入比例由10%升高至35%,最后趋于27%;滨海城市生活污水处理厂设计水量中雨水混入比例可定为25%~30%。     

Contamination potential of drinking water distribution network biofilms.

Drinking water distribution system biofilms were investigated for the presence of hygienically relevant microorganisms. Early biofilm formation was evaluated in biofilm reactors on stainless steel, copper, polyvinyl chloride (PVC) and polyethylene coupons exposed to unchlorinated drinking water. After 12 to 18 months, a plateau phase of biofilm development was reached. Surface colonization on the materials ranged between 4 x 10(6) and 3 x 10(7) cells/cm2, with heterotrophic plate count (HPC) bacteria between 9 x 10(3) and 7 x 10(5) colony-forming units (cfu)/cm2. Established biofilms were investigated in 18 pipe sections (2 to 99 years old) cut out from distribution pipelines. Materials included cast iron, galvanized steel, cement and PVC. Colonization ranged from 4 x 10(5) to 2 x 10(8) cells/cm2, HPC levels varied between 1 and 2 x 10(5) cfu/cm2. No correlation was found between extent of colonization and age of the pipes. Using cultural detection methods, coliform bacteria were rarely found, while Escherichia coli, Pseudomonas aeruginosa and Legionella spp. were not detected in the biofilms. In regular operation, distribution system biofilms do not seem to be common habitats for pathogens. However, nutrient-leaching materials like rubber-coated valves were observed with massive biofilms which harboured coliform bacteria contaminating drinking water.     

山地城市屋面雨水可利用量分析——以重庆市沙坪坝某片区为例

为定量评估山地城市屋面雨水可利用量,以重庆市沙坪坝某片区为例,分析了重庆市的降雨特征,利用改进的径流系数法定量评估了代表年屋面雨水可利用量,并分析了降雨特征对可利用量的影响;运用设计降雨量和设计暴雨强度两个指标相结合的方法确定了蓄水池规模,使其满足径流控制率和防洪减涝的要求。研究表明:在代表年降雨量为1 198.9、1 104.4和962.7 mm时,研究区域屋面雨水可利用量分别为267 951.8、247 421.3和198 917.9 m~3,雨水利用潜力较大,降雨量对可利用量的影响较大,而降雨强度对其影响很小;研究区域蓄水池总规模为9 312 m~3,屋面径流控制率达到86.4%,为山地城市雨水利用系统中蓄水池的规模设计提供了参考依据。     

低影响开发措施对雨水径流的控制效应

为了解LID措施在实际应用中对雨水径流的控制效应,选取广州市天河智慧城透水铺装和绿地开展现场监测,在透水铺装和绿地上分别选取20场次和11场次降雨径流资料分析径流削减情况,在透水铺装和绿地上均选取2场次降雨水质资料分析污染物去除情况.结果 表明:透水铺装和绿地的径流量削减率均随着雨前干旱期增加而上升,随着降雨历时、降水...     

初期弃流后板房屋面雨水污染物质量浓度衰减规律

为研究初期雨水弃流后不同降雨重现期条件下屋面雨水的污染物质量浓度变化规律,以板房屋面为例,采用3 mm的初期雨水弃流深度,基于暴雨径流管理模型(SWMM),构建了板房屋面径流模型,在采用雨水收集箱中污染物质量浓度实测值对模型验证后,模拟分析了不同降雨重现期板房屋面雨水的污染物质量浓度衰减规律.结果表明:雨水收集箱中污染...     

Evaluating the potential of biofilm control in water supply systems by removal of phosphorus from drinking water.

Effect of microbially available phosphorus (MAP) on biofilm development in drinking water systems was investigated at the pilot-scale experiments over 3 years. Completely mixed biofilm reactors Propella (water detention time 24 h, flow rate 0.25 m s(-1), PVC pipe coupons) were used as water distribution network models. Four experimental runs were carried out with water containing different levels of phosphorus which was limiting nutrient for bacterial growth. Positive correlation between MAP in the inlet water and heterotrophic plate count (correlation coefficient 0.95) in biofilm, as well as for the total bacteria number (correlation coefficient 0.71), was observed. However, our experiments showed that removal of phosphorus down to very low levels (below detection limits of chemical method and MAP < 1 microg L(-1) was not an efficient strategy to eliminate bacterial regrowth and biofilm formation (< 51,00,000 cells/cm2) in drinking water supply systems.     

Coliforms and other microbial indicators occurrence in water and biofilm in full-scale distribution systems.

Biofilm and microbial water quality were studied in four middle size full-scale distribution systems (DS) in France serving 5,000-30,000 inhabitants (maximum residence time 23-160h) through three sampling campaigns over 1 year. Three of these DSs were chosen because of a quite high occurrence of bacterial indicators (i.e. total coliforms), the last DS was considered as a reference. Biofilm was studied on cast iron coupons incubated for more than 1 month in devices continuously fed with water from the DS in conditions imitating those met in DS. The devices were located at different points (4-6) along each DS. The abundance of bacteria in biofilm was estimated by heterotrophic plate counts (HPC) after detachment of the biofilm from the support by sonication. Microbiological water quality was estimated in parallel; analysis of total coliforms, E. coli, enterococci and anaerobic sulphide-reducing bacteria spores (ASRB spores) was carried out in biofilm and water. Over the period of the study, 171 water samples and 57 biofilm samples were collected. Over these 171 waters, 19 (11%) were positive for at least one of the measured indicators while two biofilm samples were positive (3.5%). Significant differences were observed in the levels of contamination between the DSs. High residence time in the DS, low disinfectant residual and high temperature increased the risk of indicator occurrence in the water phase. Due to the low number of biofilm samples positive for bacterial indicators, the data collected in the present study did not allow observation of a direct association between biofilm and water contaminations, even if the occurrence of indicators in water appeared on DSs with the highest density of biofilm (HPC).     

城市雨水径流污染及LID控制效果模拟

采用SWMM(storm water management model)模型对城市雨水经流及水质进行模拟,分析不同降雨条件下,LID(low impact development)控制措施对城市雨水径流及污染物的削减效果。结果发现:LID控制措施对城市雨水径流量、污染物总负荷以及径流峰值均有明显削减作用,对径流峰现时间有延迟作用;雨水径流量、污染物总负荷以及径流峰值的削减率随雨峰系数的增大呈先增大、后较小的变化趋势,随重现期的增大而减小;峰现时间的延迟效果与雨峰系数和重现期均呈负相关;相对雨峰系数,重现期对雨水径流量、污染物负荷的削减率、径流峰值以及峰现时间的影响更显著。     

光伏电站发电板雨水收集模拟试验研究

为有效利用光伏电站降雨资源进行农业灌溉,以云南省楚雄州元谋县天子山光伏发电站为研究对象,进行了雨水收集模拟试验研究。通过室内1∶1比例模型设置纵向单列、纵向3列布置发电板进行人工降雨模拟试验,分析当地条件下降雨强度与集雨效率的关系。结果表明:纵向单列布置与纵向3列布置得出的集雨效率相同;瞬时降雨强度与集雨效率关系为非线性关系;集雨效率在降雨峰值(1.95 mm/min)、谷值处(0.97mm/min)分别为56.31%,31.56%。根据集雨试验成果,可确定光伏发电站发电板的雨水收集量,并据此确定适宜种植的农作物,在光伏发电站发电的同时发展农业。     

建筑废弃料对改良土壤蓄渗效果的试验及模拟研究

为了解决我国华南地区土壤质地黏重、渗透性能极差,无法及时排干随着不透水路面剧增而增长的城市径流雨水的问题,依据生物滞留池典型构造原理制备实验室自制滤柱装置,通过测试不同重现期下滤柱装置的下渗曲线,以评估不同粒径级配的建筑废弃料对土壤蓄渗的改良效果。结果表明:中小雨强下符合华南地区土壤特征和降雨条件的最优建筑废弃料粒径级配为5~9mm,且随着降雨重现期的增加,蓄渗改良效果更为明显,产渗流时间也显著提前;在SWMM中构建LID生物滞留池模块,根据试验结果进行模型率定,可为生物滞留池提供合理设定参数。研究成果拓展了建筑废弃料在低影响开发措施中的应用,以期为华南地区大规模海绵城市低影响开发措施的土壤蓄渗改造提供科学参考和评估工具。     

滨州市滨城区雨水利用分析

为了缓解滨州市滨城区水资源匮乏的危机,有效地综合利用雨水资源,根据滨城区的降雨特性和土壤因素,提出适宜当地的雨水利用措施,并分析估算了不同水平年城区雨水利用潜力及采取新措施能够利用的降雨量。结果表明:采用雨水利用措施可以解决当前滨城区水资源量匮乏的问题。     

初期径流雨水工程截流措施及效果初探

初期径流雨水是受纳水体的主要污染源,用降雨深度界定初期径流雨水量并将其截流可降低对受纳水体的污染。为便于采取工程措施有效截流初期径流雨水,以《中华人民共和国地表水环境质量标准》(GB 3838-2002)中Ⅴ类水体基本项目标准限值为依据,将污染指标值高于该标准限值的径流雨水界定为初期径流雨水,因此后期径流雨水量即为污染指标值等于或小于该标准限值时的产流量,用单位时间内的降雨体积表示。据此按钢筋混凝土圆管(满流)的水力计算图确定截流管道的管径,并采用溢流堰式截流井截流。通过实际工程验证,其截流效果显著,且工程易于实施。     

水景社区的雨水收集与综合利用设计

为研究城市雨水收集与综合利用,以上海郊区一生态水景社区为例,进行水量平衡计算。结果表明,该社区年均雨水可收集量约45 678 m3,占一年总降雨量的62%左右,不但满足社区每年的绿化浇灌、硬地冲洗以及水面蒸发等消耗量,而且富余雨水经过处理后可用作景观湖的补充水源及其他用水。雨水收集利用系统设计以景观湖为中心,屋面雨水通过2个总容积为675 m3的地下集蓄池来收集,集蓄水量可达1.83万m3/a;绝大部分绿地、道路广场以及极少数屋面的雨水径流通过长1 km的植草浅沟和500 m长的碎石沟渠收集,并汇入2个总面积为800 m2的暴雨塘系统内暂时储存。户外小停车场和小广场的雨水通过砂床过滤系统收集。     

沿海地区污水处理厂雨水混入率对设计规模的影响

以沿海地区台州某污水处理厂为例,基于三角形法,对雨水混入与污水处理厂水质、水量的响应关系进行分析,探讨雨水混入率对污水处理厂设计规模的影响。结果表明:沿海地区污水处理厂进水水质受降雨影响较大,实际进水水质因雨水混入而小于设计值;沿海地区污水处理厂处理水质效果较差,污染负荷削减率平均值远低于全国平均值;小雨时,沿海地区污水处理厂污染负荷削减率最高,污染负荷削减率随着降雨规模的增大而减小;沿海地区污水处理厂满负荷运行时,污水量处理率较低,为60%~70%;沿海地区污水处理厂实际进水量远大于设计值,水量设计规模宜考虑乘1.4的修正系数。     

Comparing the microbial characteristics of rainwater in two operating rainwater tanks with different surface-to-volume ratios

In this study, the microbial characteristics of rainwater in two tanks with different surface-to-volume ratios were investigated and compared to determine how the internal design features of storage tanks affect water quality. The particle and nutrient parameters of the rainwater, including turbidity, suspended solids, total organic carbon, and total phosphate, were lower in Tank 2, which had a surface-to-volume ratio 7.5 times greater than that of Tank 1. In addition, although the rainwater was collected from the same catchment area, the water in Tank 1 had greater numbers of bacteria, and the bacterial communities in the water differed between the two storage tanks. It appears that the differences in the inside surface structures of the rainwater tanks affected the microbial ecosystems. Increasing the surface-to-volume ratio in rainwater tanks may affect rainwater quality, because this extends the area for biofilm development. Further study of the role of biofilm in rainwater tank is required precisely, and its function needs to be considered in the design and management of rainwater tanks.     

塑性混凝土抗拉强度试验研究

为了探讨塑性混凝土抗拉强度的影响因素,采用劈拉试验方法测得塑性混凝土的抗拉强度,在大量试验的基础上,对各组成材料对塑性混凝土劈裂抗拉强度的影响进行了详细的分析,得出各因素对塑性混凝土劈裂抗拉强度的影响规律.研究结果表明,减小水胶比及粘土和膨润土的用量,增加水泥用量,适当掺加粉煤灰和外加剂,可提高塑性混凝土的抗拉强度.     

改良型透水铺装对弱透水土质地区SS的去除效果试验

为研究适用于弱透水土质的改良型透水铺装对典型雨水径流污染物悬浮固体(SS)的去除效果,以嘉兴地区的淤泥质黏土为土基层制作试验装置,以人工模拟降雨的方法模拟并检测不同降雨重现期条件下改良型透水铺装装置削减径流污染物SS的效果,并以常规透水铺装和普通路面作为对比。结果表明:较小的降雨重现期更有利于透水铺装对SS的去除;弱透水土质条件下改良型透水铺装在对SS的去除过程中,不但去除率高于常规透水铺装,去除速率也得到了提高;在降雨重现期1 a条件下,改良型透水铺装平均每分钟比常规透水铺装多去除29.82%的SS。     

植被浅沟的涝灾减灾补偿作用研究

低影响开发(LID)可以较有效地修复传统的雨洪排泄及输送系统所破坏的水文机制,本文以桐庐县瑶琳嘉苑小区为研究区域,建立SWMM模型,对该小区城市化后以及加入了植被浅沟之后在不同降雨重现期下的雨洪过程进行对比分析,并且通过改变植被浅沟的布设位置与管道出口断面的位置分析比较植被浅沟的效果,对植被浅沟的减灾效果进行研究。结果表明:植被浅沟的减灾效果在低重现期下较为明显,且植被浅沟的减灾效果随着重现期的增大而降低,当降雨重现期增加到一定值时,植被浅沟则失去了作用;当植被浅沟的布设位置距离管道出口断面较近时,减灾效果较为明显,当植被浅沟距离出口断面较远时,减灾效果下降。     

城市雨洪利用雨情分析

城市雨洪利用是解决城市缺水和防洪问题的一项重要措施.为了更好地利用城市雨洪资源,分析城区雨洪利用的潜力和效益规模,需要分析该城区的降雨资源特性,包括城区降雨总量、降雨的年内分配、年际变化及降雨的时间、空间分布特性;为了分析雨洪利用排水设施、蓄水设施规模,需要分析城区短历时暴雨、暴雨强度和设计降雨及设计降雨过程.     

Urban Rainwater Utilization and its Role in Mitigating Urban Waterlogging Problems—A Case Study in Nanjing, China

With the acceleration of the urbanization process, urban waterlogging problems are becoming more and more serious in Nanjing, China. In order to mitigate the urban waterlogging problems, it is necessary to reduce surface runoff from the source by rainwater harvesting and utilization. An urban residential district with an area of 0.58?km² in Nanjing was selected as the study area. Based on a large-scale topographic map data and the long term rainfall data (1951?C2008), the types of underlying surfaces were classified. The potentiality of collectable rainwater and the possibility of runoff volume reduction were calculated. The results showed that exploitation of rainwater harvesting from rooftops and other underlying surfaces has high potential. The annual collectable rainwater is approximately 372,284?m³, 314,034?m³ and 275,180?m³ under different cumulative frequency of rainfall at 20?%, 50?% and 75?%, respectively. The total capacity of cisterns under assumptions of return period of rainfall and rainfall duration with 5?years and 20?min is 11,022?m³. The cistern??s capacity which is used for roof rainwater harvesting is 4,083?m³, the cistern capacity for per unit roof area (1?m²) is 0.0267?m³. The results of the feasibility analysis of setting up above-ground cisterns showed that 55?% of the total roof areas in the study area are available for setting up cisterns. In the three building types, 16?% of the commercial building??s roof areas and 77?% of that of the residential and the ??others?? buildings are available for setting up cisterns. Urban waterlogging problems can be effectively reduced through rainwater harvesting by 13.9?%, 30.2?% and 57.7?% of runoff volume reduction in three cases of the maximum daily rainfall (207.2?mm), the average annual maximum daily rainfall (95.5?mm) and the critical rainfall of rainstorm (50?mm).