基于土柱淋滤实验的U天然在包气带迁移模拟研究

以某地浸铀矿山为例,基于室内土柱淋滤实验,分析了包气带对U_天然的吸附和阻滞能力,确定了U_天然在包气带中的阻滞系数和分配系数等关键溶质运移参数,并结合实验结果,采用Hydrus-3D建立包气带数值模型,预测了放射性核素U_天然在土壤包气带中的迁移规律,结果表明：包气带对U_天然有较强的吸附阻滞能力,通过实验和模拟相结合的手段,可模拟预测U_天然在包气带中的迁移过程,为地浸铀矿山土壤、地下水环境治理及风险防控提供参考。     

降水入渗对非饱和土坡稳定性的影响

降雨以液体形式入渗到土体中，同时土体中的水以蒸发的形式离开土体。两个过程的差值决定地面径流量和净入渗量。净入渗量受土体-洼质、含水率、孔隙水压力、土体中水蒸气的消散度等因素的影响。因此，降雨入渗后的暂态渗流场难以确定。将土-水-气三相耦合，提出了一种确定降雨入渗后的暂态渗流场的模型。最后，结合工程实例分析了降雨入渗后渗流场的变化对土坡稳定性的影响。     

基于包气带动力学的长白山天然矿泉水水源地土壤吸附能力研究

为了提高水源地包气带土壤的吸附能力,提出基于包气带动力学的长白山天然矿泉水水源地的土壤吸附能力研究方法。根据长白山地区的地质概况,发现水源地包气带可以吸附和净化污染物,以长白山天然矿泉水水源地包气带为研究对象,将其划分为东郊、南郊和北郊3个水源地包气带。结合动力学实验,测试了3个水源地包气带对苯酚和柴油的吸附能力。结果表明,3个长白山天然矿泉水水源地包气带对苯酚的吸附速率分别为19.145 5、21.554 5、19.695 5 mg/（kg·h）,对柴油的吸附速率分别为1.734 725、2.282 9、2.995 925 mg/（kg·min）,说明白山天然矿泉水水源地包气带土壤对苯酚和柴油的吸附能力较强,可以提高长白山天然矿泉水水源地的土壤吸附能力。     

包气带中污染物迁移转化规律研究

评述了包气带中无机污染物和有机污染物迁移的机理及国内外研究现状，说明了模拟污染物在包气带中迁移转化规律的数学模型及其应用条件，从而为控制包气带及地下水的污染奠定了基础。     

A Multiple Interactive Continua Model (MINC) to Simulate Reactive Mass Transport in a Post-Mining Coal Zone: A Case Study of the Ibbenbüren Westfield

We tested the suitability of the multiple interactive continua approach (MINC) to simulate reactive mass transport in a disturbed post-mining coal zone. To the authors’ knowledge, this approach has not been employed in such mining settings despite its relative success in other environmental fields. To this end, TOUGHREACT software was used to set up a MINC model of the unsaturated overburden of the Ibbenbüren Westfield. With it, we examined and evaluated water–rock interactions in both the fractured and porous continua as the main driver of elevated hydrogen, iron, sulfate, and chloride concentrations in the coal mine groundwater. Long and seasonal geochemical signatures were obtained by formulating and applying a five-stage modelling process that depicts the mining history of the area. The simulation results agree well with the concentrations and discharge trends measured in the mine drainage. Oxygen and meteoric water flow through the fractured continuum, leading to a high and steady release of hydrogen, iron, and sulfate ions derived from pyrite oxidation in the matrix continua closest to the fractures. Likewise, high chloride concentrations resulted from the mixing and gradual release of relatively immobile solutes in the matrix as they interacted with percolating water in the fracture. In both cases, the use of a multiple continua approach was essential to resolve sharp gradients for advection and faster kinetic reactions, while reducing the model’s dependence on block size for diffusive transport at the fracture–matrix interface. The model further allows for the calculation and analysis of solute exchange and transport in the unsaturated overburden resulting from rebound and imbibition processes, something pioneering when compared to other models in the field.

     

基于三元混合模型的滨海金矿矿井涌水水源分析

为查明三山岛深竖井建设区域矿井涌水源,选用三元混合模型分析法对三山岛矿井涌水水样进行化验分析,利用矿化度(M)和SO2-4、Mg2+浓度的线性相关性,建立地下矿山涌水源三元混合模型并计算.结果表明:模型方法简单便于操作,能够很好地判断矿井涌水水源构成;矿井涌水在浅部主要来源于海水,其次是基岩卤水,少量第四系水,随深度增...     

应用定位通量法计算某区潜水垂向入渗补给量的适宜性分析

依据新疆地勘局昌吉地下水均衡试验场不同水位埋深条件下的地渗仪、负压计和中子仪组合观测资料，分析了定位通量法计算内陆干旱区潜水垂向入渗补给量的适宜性；结果表明：定位通量法不能用于计算内陆干旱区降水入渗补给量，可应用于水位埋深4～7m，包气带岩性为粘土的潜水田间灌溉入渗补给量。     

地面L型定向分支孔注浆加固煤层顶板厚风氧化带技术研究

针对薄基岩、厚风氧化带下综采工作面顶板压力大,易形成出水、压架事故的工程问题,采用一种新型L型定向分支孔结构对顶板厚风氧化带进行了地面预注浆,设计了合理的注浆参数和施工技术措施。工程实践结果表明：采用地面多渗透源的注浆方式加固顶板风氧化带,注浆压力大,改善了上覆围岩结构的力学行为,封堵了砂岩裂隙水和上部含水层的导水通道,配套高强液压支架,实现了安全回采,为同类地质条件下工作面开采提供了一种新的技术途径。     

地表水体作用下的粗颗粒地层渗透规律研究

在地表水体(人工湖或水库)长期作用下,粗颗粒地层(卵石或漂石)形成了复杂的渗透规律,与传统认识存在较大差异。因此,查清人工湖或水库底下的土层渗透规律和地下水分布条件直接关系到工程的安全、造价和工期。该文结合工程实例,初步研究了在地表水体长期作用下粗颗粒地层的渗透规律,突破水文地质学中"含水层"和"隔水层"的传统定义,首次提出"饱水层"的概念。浅层地下水的排泄以垂向渗流为主,深层地下水排泄以径流为主;浅层地下水的补给以地表水补给为主,深层地下水的补给主要是浅层地下水通过非饱水带对其补给。     

Physical, Hydrologic, and Aqueous Chemical Characterization of the Ore Knob Tailings Pile (Ashe County, North Carolina, USA)

Oxidation of pyrrhotite and related sulfide minerals in the vadose zone of the Ore Knob Mine tailings pile generates dissolved Fe⁺², SO₄⁻², and acidity, which are rapidly transported through the pile by infiltrating surface water. Significant spatial variations in the physical and hydraulic characteristics of the tailings cause large variations in air-filled porosity and effective oxygen diffusion into the pile. Tailings in the upstream areas are more fine-grained, with less air-filled porosity and oxygen diffusivity. The original tailings in the downstream areas are more coarse-grained, with less water retention and greater oxygen diffusivity. However, weathering processes have increased the fine-grained fraction in the oxidized zone and hardpan layer, increasing water retention and lowering oxygen diffusivity. The thickness of the downstream oxidized zone combined with increased water retention due to weathering may have significantly reduced acid generation in these areas.     

Characteristics of produced water during coalbed methane (CBM) development and its feasibility as irrigation water in Jincheng, China

Water resources are scarce in Jincheng. Huge quantities of water are pumped out in the dewatering course, and the disposal of CBM water is one of the most important problems during the extracting of CBM. Based on the data of CBM water production, chemical characteristics, the irrigational conditions for major crops, and China irrigation water standard, the feasibility of CBM water as irrigation water is discussed. The result shows the CBM water quality doesn’t fully meet irrigation water quality standards in Jincheng, its high salinity and sodium adsorption ratio (SAR) in CBM water might affect crops growth and lead to yield loss, and can’t be used as irrigation water directly, but with the treatment of the reverse osmosis (RO) to lower the salinity and SAR of CBM water, the CBM water can be used as irrigation water.     

Long-term Evaluation of a Composite Cover Overlaying a Sulfidic Tailings Facility

Abstract.  A high density polypropylene (HDPE) and bentonite composite cover, used to reduce oxygen ingress into a sulfidic tailings facility, was evaluated over a 7 year post-installation period between 1998 and 2005, and found to be a reliable long-term barrier to oxygen ingress and rainfall infiltration. The evaluation was based on multiple lines of evidence and included (i) changes in metal and inorganic concentrations in the regional ground water immediately underlying the tailings residue; (ii) oxygen concentrations from probes installed below the composite cover; (iii) changes in pore water levels within the tailings residue, and; (iv) changes in temperature of the vadose zone below the composite cover. While no systematic reduction in metal and inorganic concentrations were observed, oxygen concentrations from most probes installed below the composite cover showed no measurable oxygen (< 0.01%) and indicated that oxygen ingress through the composite cover was slow, compared to oxygen consumption in the tailings residue. The decline and stabilization in pore water levels over time within the tailings residue provided evidence that the cover effectively reduced infiltration of rainfall-recharge through the tailings residue. Temperatures below the composite cover were offset and attenuated with depth, and showed a decrease in temperature (especially at the deepest location just above the tailings residue), suggesting that the exothermic sulfide oxidation reaction process was not maintained after the cover was installed.     

立井基岩风化带工作面深孔预注浆

晋城煤业集团赵庄煤矿二号井东回风立井井筒所穿越的基岩强风化带,虽然厚度不太大,但含水层较多,涌水量较大,水文地质条件复杂。本文简要介绍了复杂地质条件下,工作面深孔通过基岩风化带,并且保证优质工程的施工经验。     

降雨入渗对非饱和土体边坡稳定性影响及治理对策

为研究降雨入渗对非饱和土体边坡稳定性影响,基于饱和-非饱和渗流理论,分析了降雨入渗条件下边坡内部渗流场变化及其对边坡稳定性的影响。研究表明：①降雨入渗是饱和-非饱和过程,其内部体积含水率随降雨持续时间的变化而发生动态改变,在降雨初期,土体处于非饱和状态,黏聚力随着含水率的增大而增大,内摩擦角变化幅度较小,总体呈下降趋势,基质吸力增强,安全系数升高,对边坡稳定性有利;②随着降雨持续,孔隙水压力由负变正,黏聚力和内摩擦角随着含水率的增大而减小,基质吸力减弱,边坡稳定性降低;③降雨入渗终态过程为内部水位线升高,动静水压增加,土体有效重度降低,土体发生软化,力学强度参数降低,边坡稳定性随之降低,土体渗透系数与边坡安全系数总体成反比关系。在上述分析的基础上,结合土质边坡实例,应用强度折减法,分析了降雨入渗状态下边坡潜在滑动面、峰值位移随降雨持续时间的变化规律,认为降雨初期潜在滑动面由浅入深,峰值位移不断增大;降雨停止后,土体内部应力重新分布,土体由饱和转为非饱和,潜在滑动面、峰值位移发生逆变化。为防止降雨条件下边坡发生失稳破坏,针对性地提出了土质边坡治理建议,为非饱和土体边坡综合治理提供了有益参考。     

降雨入渗对非饱和土体边坡稳定性影响及治理对策

为研究降雨入渗对非饱和土体边坡稳定性影响,基于饱和—非饱和渗流理论,分析了降雨入渗条件下边坡内部渗流场变化及其对边坡稳定性的影响。研究表明：①降雨入渗是饱和—非饱和过程,其内部体积含水率随降雨持续时间的变化而发生动态改变,在降雨初期,土体处于非饱和状态,黏聚力随着含水率的增大而增大,内摩擦角变化幅度较小,总体呈下降趋势,基质吸力增强,安全系数升高,对边坡稳定性有利;②随着降雨持续,孔隙水压力由负变正,黏聚力和内摩擦角随着含水率的增大而减小,基质吸力减弱,边坡稳定性降低;③降雨入渗终态过程为内部水位线升高,动静水压增加,土体有效重度降低,土体发生软化,力学强度参数降低,边坡稳定性随之降低,土体渗透系数与边坡安全系数总体成反比关系。在上述分析的基础上,结合土质边坡实例,应用强度折减法,分析了降雨入渗状态下边坡潜在滑动面、峰值位移随降雨持续时间的变化规律,认为降雨初期潜在滑动面由浅入深,峰值位移不断增大;降雨停止后,土体内部应力重新分布,土体由饱和转为非饱和,潜在滑动面、峰值位移发生逆变化。为防止降雨条件下边坡发生失稳破坏,针对性地提出了土质边坡治理建议,为非饱和土体边坡综合治理提供了有益参考。     

小保当井田基岩风化带含水层富水性分析

在陕北侏罗系煤田中,除着重分析萨拉乌苏组含水层富水性之外,大面积的基岩风化带也是防治水工作的重中之重。为做好疏放水工作,预防突水事故的发生,在梳理分析井田水文地质资料、区域构造、前人研究结论及区内风化带厚度、岩性、风化程度等的基础上,结合瞬变电磁勘探解释成果,以小保当井田部分勘查区为例,对其基岩风化带含水层的富水性进行了综合分析。初步圈定了区内基岩风化带富水异常区,并借鉴区内其他含水层富水性统一得出趋势结论。总结了风化岩特征及富水性影响因素后,结合其他含水层富水情况,发现本区基岩风化带的富水性为弱-中等,在测区西南部、东北部富水性较强,对开采工作有一定的影响,该研究成果可以为煤层开采过程中的疏放水工作提供一定的指导。     

煤矿井下断层渗流特性与注浆防渗效果分析

针对宝黎断层丰水季节导致周源山煤矿北大巷涌水量变大的问题,利用RFPA-Flow数值模拟软件分析得出断层的渗流量与水压呈正比例关系,沿着水流方向,水压和渗流量都逐渐减小;随着至断层距离的增加,水压和渗流量逐渐减小;注浆后,断层处水的主要渗流通道被封堵,水只能从断层周围的岩体裂隙向断层渗流,渗流量大幅降低。注浆前后实测的周源山煤矿北大巷涌水情况与数值模拟结果一致。现场采用双液高压帷幕注浆技术处理后的断层破碎带透水率达到了岩石地基工程防渗标准。     

Modelling the Long-term Release of Sulphate from Dump Sediments of an Abandoned Open Pit Lignite Mine

Abstract.  The generation of acid drainage from overburden spoil piles at open-pit lignite mines impacts water quality in large parts of the Lusatian mining area in Germany. The Lohsa Mine was exploited until the early 1990s and is to be flooded by 2005. It will then be used as a reservoir basin for the river Spree. Future acidity and sulphate concentrations in the surface water are of great interest because considerable amounts of the bank filtrate of the river are used to supply drinking water to communal water plants downstream. In our study, the input of sulphate from the unsaturated zone of the heap into the groundwater was calculated using the one dimensional reactive transport code SAPY. The SAPY program, which had been calibrated for effective diffusion and tortuosity using oxygen breakthrough curves of a column experiment with original heap sediments, was scaled up to field conditions and verified by measuring the oxygen and sulphate profile of the heap. Scenarios for a period of 80 years were simulated for different distances of the groundwater level to the subsurface, and the mass input of sulphate from the unsaturated zone into the groundwater was calculated in terms of specific fluxes for different times. Plans are to use the calculated source terms in a regional three-dimensional model to predict the evolution of the ground- and surface water in the area.     

Modeling Irrigation with Gypsiferous Mine Water: A Case Study in Botswana

The possible use of mine effluent for irrigation of agricultural crops was investigated for BCL Ltd. nickel mine (Selebi Phikwe, Botswana). The aims were to estimate the long-term water and salt balance under irrigation with gypsiferous mine water, as well as to make recommendations on cropping and management options. A simple but mechanistic edynamic soil water-salt balance generic crop growth model (SWB, Soil Water Balance) and a weather data generator (CLIMGEN) were used for long-term predictions. Eleven years of irrigation with BCL effluent were simulated for different cropping systems and irrigation management practices, followed by 39 years of irrigation with freshwater or dry land cropping. The long-term simulations indicated that between 661 and 2017 mm of mine effluent could be used annually through irrigation, depending on crop choice and irrigation management. Between 18% and 32% ot the total amount of salt added through irrigation was predicted to leach in 11 years, the remainder being precipitated in the 1.1 m deep soil profile in the form of gypsum. The rate of gypsum dissolution and leaching after 11 years of irrigation with mine water depended on management. Simulated root density-weighted electrical conductivities at saturation indicated favorable conditions for growth of summer crops, but a leaching fraction is recommended in winter. A lucerne perennial pasture was the most suitable cropping system from the point of view of mine water utilization and salt precipitation in the soil profile. Deficit irrigation (room for rain) followed by dry land cropping was the most suitable management strategy in order to limit salt leaching and possible ground water contamination. The acceptability of the proposed strategies will depend on Botswana's standards for environmental protection, as well as social and economic issues.     

土壤水分入渗实验及其运动规律分析

土壤污染问题已经成为当今社会的首要问题,为了探究污染物随土壤水在土壤中的运移规律,首先要摸清水分在土壤中的入渗规律。设计了5组实验,考察了水分在非饱和土壤中的入渗过程,记录了不同位置含水率随时间的演化;针对实验数据,通过绘图进行了统计分析,总结了水分在非饱和土壤中的入渗规律。此次实验器材均根据自身实验需求设计,目的是方便对土柱内含水率的测定以及数据记录。