屋面雨水回灌裂隙岩溶水水岩作用实验研究

在济南大学西校中采集奥陶系灰岩岩样,并设置不同的地下水、雨水混合比例进行室内溶蚀模拟实验。通过pH、电导率及几种常规离子的测定,并利用水文地球化学模拟软件PHREEQC等方法,分析雨水回灌含水层后与原有的地下水以及含水层介质之间的水—岩相互作用。结果表明:(1)地下水、雨水混合后,随振荡的持续进行,以及温度升高和脱碳酸作用的影响,水中CO2分压不断下降;(2)Ca2+浓度在混合比例为9∶1、7∶3和5∶5时略有下降,其它离子浓度无明显变化;(3)随雨水和岩溶系统作用时间的增加,方解石、白云石和石膏的饱和指数均不断减小,且随着雨水回灌量的增加,方解石、白云石饱和指数减小明显,从混合比例9∶1时的0.23~-0.39和0.05~-0.97到1∶9时的-0.34~-0.62和-1.59~-2.57,表明雨水能增强对方解石、白云石乃至整个含水层的溶蚀,且雨水回灌量越大,溶蚀作用越强烈,影响越明显;(4)雨水回灌所形成的溶蚀量比较有限,不会对回灌井周围含水层稳定产生严重影响。      

城市屋顶雨水回灌裂隙岩溶含水层的国内外案例介绍——兼对济南市屋顶雨水回灌裂隙岩溶含水层问题的思考

通过监测和分析济南市市区降水、屋面雨水水质和水量过程,屋顶雨水属微污染类水,经前期雨水弃流和预处理达到一定质量标准,通过管井回灌到裂隙岩溶含水层,可用于饮用水供水和保护地下水环境。已做的示踪试验表明,北方岩溶含水介质多属多重裂隙岩溶通道,因此在人工开采条件下,回灌应关注快、慢速流带来的不同水质变化问题,包括屋面雨水与裂隙岩溶介质的水岩作用。澳大利亚的案例说明,裂隙岩溶含水层对不同污染物有着不同的衰变效果。100多年来Mount Gambier市城区雨洪水经非承压石灰岩含水层径流一直排放到作为城市供水的蓝湖,到目前它对蓝湖水质没有表现出任何可量度的损害。但对于济南市的屋顶雨水回灌裂隙岩溶含水层,仍有许多问题需要研究。      

屋顶雨水回灌裂隙岩溶含水层连通示踪试验

雨水回灌后对岩溶水的影响分析和效果需要对回灌井和下游的观测井监测数据说明。由于岩溶含水层中岩溶发育极不均匀,在测定地下水位并判定出地下水流向的基础上,连通示踪试验是选择与回灌井相对应的观测井的有效办法。用氯化钠作为示踪剂,监测不同测井不同埋深地下水电导率随时间变化的方法确定了岩溶水观测井选址、岩溶含水层的结构及水文地质条件。示踪试验结果表明,3#观测井(西院井)可用来监测雨水回灌效果,并计算出该地区的地下水势流速在9 m/h～20 m/h之间。该成果对北方地区岩溶含水层回灌和环境评价具有重要的参考价值。     

济南市玉符河多水源回灌岩溶水水质风险评价

济南以泉城而闻名,保泉和供水安全问题是其面临的巨大挑战,利用多水源进行岩溶水回灌是解决问题的有效措施之一,但是补给水源水质相对岩溶水而言较差,回灌到地下可能存在一定健康和环境风险,需要对回灌系统的水质进行风险评价。本文对比地下水质量标准和地下水水质背景值,重点选择地表源水超标和劣于背景值的风险源监测指标,借鉴澳大利亚含水层补给管理指南,对玉符河多水源回灌岩溶含水层工程运行期的水质风险进行评价。2015年对黄河水、卧虎山水库两种水源多次回灌期间的源水、孔隙水和岩溶水的22项指标进行水质监测和指标分析,风险残余评价结果表明黄河水回灌补源期间,平均浊度的标准指数源水是1.4,孔隙水1.7,岩溶水0.93,硫酸盐平均含量的标准指数源水是0.93,孔隙水0.9,岩溶水0.73,氯离子虽没有超过地下水III类标准,但是在源水中含量是地下水含量的2倍多;卧虎山水库水回灌补源期间,平均浊度的标准指数源水是2.4,孔隙水1.1,岩溶水0.43,硫酸盐平均含量的标准指数在源水0.75,孔隙水0.84,岩溶水0.66,氨氮的平均含量的标准指数源水1.14,孔隙水1.47,岩溶水1.35。因此,浊度、硫酸盐和溶质在裂隙岩溶含水层迁移较快为两种水源玉符河回灌补源工程的共同高风险项和关键控制点。此外,黄河水补源还需注意盐度,卧虎山水库水补源还需控制营养物的污染风险。基于以上评价,还提出了限制回灌量占区域岩溶水资源量比例等建议。      

西南岩溶山区某石化类场地地下水污染风险评价

本论文以西南岩溶山区某石化类场地为例,以污染场地风险评价导则作为指导,结合国内外地下水污染风险评价方法,在完成场地地下水污染风险识别以及源项分析的基础上,建立了符合场区实际水文地质条件的地下水水流及溶质运移数值模型,对不同情形下污染物泄露对场区浅层孔隙-溶蚀裂隙地下水的影响进行预测,结合预测结果建立了场区地下水污染风险...     

中国南方岩溶地下水面源污染风险评价及防控对策

我国南方发育分布了约80万km2的碳酸盐岩地层、3620个岩溶地下水系统,赋存了1806×108 m3/a岩溶水资源,为南方69个城市约5000万城市居民及8000多万农村人口提供了供水水源.但是岩溶水受到了程度不同的污染,而农业面污染源对岩溶水所产生的污染已经远远超过非面源污染,威胁着岩溶地区供水安全.岩溶地下水污染风险评估研究意义重大.作者在全面系统地分析了南方岩溶水特点、污染类型及污染途径等的基础上,结合已有的实验研究结果总结了岩溶地下水污染的防护能力,提出了污染风险识别、污染概率估算、污染风险评价与防控的理论方法,并以贵阳为例,对岩溶地下水面源污染风险进行了评价,针对岩溶地下水面源污染特点提出了防控对策.     

贵州典型岩溶区岩溶地下水污染评价

本文选取贵州三个岩溶典型类型,即地下水集中排泄类型,地下水集中开采区类型和城镇区岩溶地下水类型,根据各类型岩溶区的岩溶发育特征,水文地质条件,地下水污染类型和方式,分别用集中参数模型和分布参数模型,对地下水污染进行了评价,所得结果均拟合良好。     

密县盆地裂隙岩溶水资源评价

本文运用水均衡方法,对密县盆地地下岩溶水资源及允许开采量等进行了分析。并利用地下水长观资料及水文地质资料,对其水文地质参数进行了计算。在此基础上,建立了裂隙岩溶水数学模型,同时用有限单元法对地下水资源进行了进一步评价,得出了较为满意的结果。      

昆明新机场南区岩溶分布规律及稳定性评价

对大量钻探、物探资料进行研究,系统分析场地岩溶分布规律,对岩溶地基稳定性进行系统评价,为新机场南区工程建设提供重要依据。     

城市屋面雨水收集利用工程设计分析

城市雨水作为第三水源开发利用,在其3种汇流介质(屋面、道路、绿地)中,屋面雨水水质相对较好、便于收集,宜于直接利用.以济南大学西校区第1教学楼为例,进行了屋面雨水回灌裂隙岩溶含水层工程及主要构建物的设计,并预算了工程年平均可利用雨量.     

Geochemical and flow modelling as tools in monitoring managed aquifer recharge

Due to a growing world population and the effects of anthropogenic climate change, access to clean water is a growing global concern. Managed aquifer recharge (MAR) is a method that can help society's response to this increasing demand for pure water. In MAR, the groundwater resources are replenished and the quality of the recharged surface water is improved through effects such as the removal of organic matter. This removal occurs through mechanisms such as microbial decomposition, which can be monitored by studying the isotopic composition of dissolved inorganic carbon (DIC). Nevertheless, the monitoring can be difficult when there are other factors, like dissolving calcite, affecting the isotopic composition of DIC.The aims of this study were to establish a method for monitoring the decomposition of organic matter (dissolved organic carbon – DOC) in cases where calcite dissolution adds another component to the DIC pool, and to use this method to monitor the beginning and amount of DOC decomposition on a MAR site at Virttaankangas, southwestern Finland. To achieve this, we calculated the mean residence times of infiltrated water in the aquifer and the fractions of this water reaching observation wells. We conducted geochemical modelling, using PHREEQC, to estimate the amount of DOC decomposition and the mineral reactions affecting the quality of the water.     

承压含水层非完整反滤回灌井的稳定流计算

反滤回灌井是地下水库中一种有效的回灌设施,它由回灌井和井口反滤层组成。非完整反滤回灌井井流运动由砂反滤层的竖向流和非完整回灌井井流组合而成。文中提出了承压含水层非完整反滤回灌井稳定流的计算方法,分析了反滤层、井损和回灌堵塞等因素对回灌量的影响,并结合实例证明了反滤回灌井回灌量大大低于普通回灌井的回灌量。     

海绵城市建设地下水补给计算研究进展

海绵城市建设通过改变流域下垫面条件来蓄滞雨洪,在减少城市雨水地表径流量、缓解城市内涝、补给地下水方面发挥了重要作用。在此过程中,增加流域雨水下渗量、利用雨水回补地下水是海绵城市建设的重要手段,也是雨水资源利用和缓解城市水资源短缺的重要举措。针对当前海绵城市建设中地下水回补量化的难题,本文对国内外适用于海绵城市建设中地下水补给量的计算方法进行了概述,分别介绍了各方法的基本原理、优缺点及适用情况,旨在为我国海绵城市建设地下水补给的效果评估提供参考。     

利用城市雨水回灌地下水防治地面沉降技术方法探讨

阐述城市化快速发展日益突显的城市雨水问题与地下水超采引起地面沉降危害,在对城市雨水收集处理进行水质分析基础上,探讨城市雨水直接回灌浅层含水层在地面沉降防治中的利用潜力和意义.     

Use of treated wastewater for managed aquifer recharge in highly populated urban centers: a case study in Addis Ababa,Ethiopia

Fast population growth and rapid industrialization, on one hand, and lack of sewerage network and poor living condition, on the other, have led to the deterioration of surface and ground water quality in the city of Addis Ababa. The urban wastewater is discharged largely into streams that drain the city. Only less than 3% join the wastewater treatment facilities. Due to sporadic rainfall that causes shortage in groundwater recharge, managed aquifer recharge (MAR) experiment was tested on soil column collected from Akaki Well Field which is located in the southern part of the city using water from the Big Akaki River that crosses the same well field and effluent from Kaliti Wastewater Treatment Plant. Water quality analysis for 17 different parameters was done for both the inflow and outflow water samples and soils were tested for electrical conductivity and cation exchange capacity. The results indicate improved water quality as a result of higher attenuation/filtration capacity of the vadose zone in the well field due to the presence of vertisols. The main geochemical processes that have acted in the soil column could be cation exchange, dissolution, precipitation, oxidation, nitrification, die off etc. that are responsible for the effectiveness of vadose zone for MAR.     

通过永定河渗漏补给地下水的适宜性评估研究

受气候变化和人类活动等因素的综合影响,地下水超采和含水层水量亏空已成为备受关注的全球性问题。为了弥补含水层水量亏空和促进地下水资源涵养,已探索出多种人为干预地下水补给的措施,其中通过河道开展地下水人工补给由于具有明显优势而受到重视。已有实践表明,受渗漏补给潜力和包气带调蓄能力等的限制,并不是所有河流或河段都适宜开展地下水人工补给工作。目前缺乏为大家广泛接受的适宜性评估方法。本研究以永定河生态补水为契机,以北京平原段河道和下伏含水层为研究区开展了案例研究,并用实测数据对研究结果进行了检验。应用指标体系法建立的适宜性评估模型（LMBGITSC模型）包括河床土地利用类型、河床介质类型、河床宽度、河床地形坡度、包气带介质类型、包气带厚度、包气带给水度、包气带水平渗透性等8个指标。案例研究结果表明,沿河流流向,通过河道渗漏补给地下水的适宜性由好变差（防渗河段除外）。该规律主要受渗漏补给潜力和包气带调蓄能力控制,因此适宜性也呈现出“阶梯式”演变规律。检验结果表明所建的评估方法适用性较好。该方法具有可移植性,因此也可为其他同类地区提供参考。     

The effectiveness of artificial recharge in combating seawater intrusion in Salalah coastal aquifer, Oman

The Salalah central sewage treatment plant has been designed to treat 20,000 m³/day at the first stage and two further stages to double the initial capacity. The plant currently (2005) treats more than 15,000 m³/day effluents to a tertiary level, and after chlorination phase, the effluents are recharged into tube wells in a line parallel to the coast. The process aims to help stabilize the seawater interface and a part to be recovered from hand-dug wells/boreholes further inland and downstream. A three-dimensional flow and solute advection transport model was developed to assess the effectiveness of the proposed recharge scheme and to track the solute transport with respect to the design system. The advection transport model predicted that in 2020 the maximum pathlines of the injection fluids would reach the abstraction wells that are located 600 m, southward of the injection bores in about 1-year travel time in the case of the no-management interference and more than that southward under management interference. The developed flow predicted the wedge of the saline intrusion in 2019 is tracked up to 2.7 and 3.4 km from the shoreline with the injection and without the injection, respectively under constant underflow. The injection scheme is effective in pushing back the saline zone front by 700 m. This study argues that the treated wastewater would help to increase the water levels at the vicinity of the injection line and to reduce the influence of saline inflows from the coast. The reclaimed sewage recharge scheme is examined in the case of the Salalah coastal aquifer using groundwater simulation, which can also be applied to other regions with similar conditions.