三维激光扫描技术在排土场方量计算中的应用

运用Riegl VZ-400三维激光扫描仪对排土场进行了扫描,并对扫描数据进行了去噪、拼接、坐标转换、格式转换的处理,将排土场的点云数据以及原始地形分别生成栅格数据,运用ArcGIS中填挖方的计算方法对排土场的方量进行了计算,得出排土场的现有方量为78.9×104m3,已经超出了其设计的65×104m3,存在安全隐患,需采用有效措施进行防范。     

基于高密度电阻率成像法的基岩裂隙网络原位识别试验研究

对于以低渗透性基岩为处置围岩的核废物地质处置库来说,基岩中的裂隙网络是地下水进入处置库和放射性核素从处置库向外界环境迁移的主要通道。因此,研究基岩内裂隙网络的空间分布特征,对核废物的地质处置是否安全具有十分重要的意义。本文以花岗岩为例通过野外试验,分析研究了利用高密度电阻率成像法（ERT）,对处于不同状态条件下的基岩中裂隙网络进行三维原位识别的效果及能力。结果表明在以高阻值为主要电特性的基岩中,利用ERT对基岩中三维裂隙网络进行原位识别是可行的,并且裂隙的电阻率特征能较好的反映出裂隙的空间分布位置和形态,但对裂隙网络识别的效果与测线方向有关。     

城市生活垃圾生态填埋技术研究概况和进展

对城市生活垃圾生态填埋技术的发展概况及研究进展进行了综述,包括生态填埋技术的概念、意义、现状和发展趋势,并提出了目前该领域研究中需重点研究的课题和一些新的思路。     

沸石净化剂制备及治理造纸废水应用试验

将８０目信阳上天梯斜发沸石岩经水润湿后,与水解后能形成多核、多羟基、高正电的铝盐、铁盐按一定比例混合,同时加入适量的反应助剂充分搅拌;然后将混合物的ＰＨ值调至４￣５并陈化数小时;最后将混合物在２００￣２５０℃的温度下烧结制成“沸石净化剂”。用该净化剂处理ＰＨ≈９、ＣＯＤＣｒ〈３５００ｍｇ／Ｌ的草浆型造纸终端废水,若重量比为１：９００,则可使ＣＤＯＣｒ降低到４５０￣９６０ｍｇ／Ｌ,达到国家造纸行业２     

Subsurface variations in arsenic mineralogy and geochemistry following long-term weathering of gold mine tailings

Variations in arsenic (As) mineralogy and geochemical controls on its mobility were evaluated in subsurface tailings at the historical Montague and Goldenville mine sites in Nova Scotia, Canada. Tailings at these sites contain some of the highest As concentrations in Nova Scotia and are located in close proximity to local communities. Pore water in the subsurface tailings is characterized by circumneutral to alkaline pH (6.2 to 8.7) and mildly reducing to oxidizing redox conditions (+130 mV to +347 mV). Bulk chemistry, scanning electron microscopy, and synchrotron micro-X-ray diffraction analyses showed As mineral hosts differ with depth. The deepest tailings (max. 2 m) are in direct contact with partially decomposed vegetation, which supports reducing conditions and the precipitation of authigenic As and Fe sulfides. Under reducing conditions, dissolved As concentrations are also controlled by desorption of As from dissolution of Fe and Mn oxides and the sorption or co-precipitation of As with carbonates. These geochemical controls differ from those influencing dissolved As concentrations under oxidizing conditions. In the near surface, As mobility is controlled by oxidative dissolution of primary arsenopyrite, precipitation of secondary Fe arsenates, Fe oxyhydroxides and Mn oxides, secondary Ca-Fe arsenates, and sorption onto Fe oxyhydroxides and gangue minerals. Some of these mineral species are stable under different conditions yet occur in close association, indicating the importance of microenvironments. The results of this study show that the weathering characteristics of these tailings vary with depth, leading to the formation of new As hosts that are distinct from those observed in the near surface. Identification of these As hosts provides an understanding of current controls on As mobility and has implications for future reprocessing and/or remediation efforts.     

极低放废物近地表处置的环境安全评价方法研究

放射性废物处置是当前严峻的环保问题之一,从经济、安全和高效角度出发,将极低放废物从中、低放废物中分离出来单独处置,对核废物的管理与处置具有重要意义。本文以我国西南某极低放废物备选处置场为研究对象,系统分析了处置的相关技术方法,重点研究了屏障技术和环境安全评价方法及其应用。针对拟建在古泥石流体山区山顶上的处置场,选取核素90Sr作为处置对象,选用盆状屏障式处置库,估算产生的核素90Sr的总活度和比活度。选用筛分的颗粒d<1 mm的介质作为屏障材料,厚度为0.5 m,批试验结果显示上述材料对90Sr的吸附效果明显;模拟计算结果显示核素90Sr在50 a内被完全阻滞在包气带中,可以达到安全处置废物的要求。     

甘肃北山地质处置库围岩节理抗剪强度经验估算

节理抗剪强度参数是地质处置库预选地段工程地质对比和围岩稳定性分析的重要指标。本文在旧井地段英云闪长岩节理分组的基础上,运用定向统计测量方法估测节理粗糙度系数,通过评价节理粗糙度系数的尺寸效应,确定节理抗剪强度经验估算有效长度,由JRC-JCS模型求得各组节理4个方向的抗剪强度参数,并评价了地质处置库围岩节理抗剪强度的各向异性特征。     

有机固体废物快速发酵剂的制备及其效果研究

从发酵的垃圾、淀粉厂污泥、腐烂桔杆等样品中，分离、纯化、诱变、筛选出分解纤维素、淀粉能力较强的4种菌株，按不同比例混合制备出有机固体废物发酵剂。从4种菌抹中选择出有较强分解能力的一组最佳配比为快速发酵剂，对有机固体废物进行分解性能实验，有机固体废物加入发酵剂后，温度迅速升高，2—3d就可以保持在70℃，提高了对纤维素、本质素及蛋白质的分解率，大大缩短了发酵周期。     

Flow and transport through clay membrane barriers

Flux equations for liquid and solute migration through clay barriers that behave as semi-permeable membranes used in waste containment and remediation applications, known as clay membrane barriers (CMBs), are discussed. The results of a simplified analysis of flow through a geosynthetic clay liner (GCL) using measured values for the chemico-osmotic efficiency coefficient (ω) of the GCL indicate a total liquid flux that counters the outward Darcy (hydraulic) flux due to chemico-osmosis associated with clay membrane behavior of the GCL. Also, the solute (contaminant) flux through the GCL is reduced relative to the solute flux that would occur in the absence of membrane behavior due to chemico-osmotic counter advection and solute restriction. Since diffusion commonly controls solute transport through GCLs and other low-permeability clay barriers, the implicit (empirical) correlation between ω and the effective salt-diffusion coefficient of the migrating contaminant is an important consideration with respect to contaminant restriction in CMBs.     

孔隙气压对核废物地质处置热-流-固耦合影响的有限元分析

为考察孔隙气体压力对高放废物地质处置中的热-流-固耦合过程的影响,借用Leiws等建立的可变形孔隙介质中非等温空气流和水流模型,在其水连续性方程中加入了温度梯度引起的水分扩散项,研制出相应的热-水-气-应力耦合弹塑性二维有限元程序。针对一个假定的高放废物地质处置库模型,在相同的初始温度、孔隙水压力和岩体应力条件下,取3种缓冲层中的初始孔隙气体压力,通过数值模拟考察了处置库近场的主应力、饱和度、气和水的流速、温度和孔隙压力的分布与变化。结果显示,当缓冲层中的初始孔隙气压力较高时,其对围岩中应力影响较大。