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61.
针对黔西南水银洞金矿坑道钻探施工中的特大涌水钻孔,总结了该矿区坑道钻探施工难点,研究了涌水对钻进效率和岩心采取率的影响,探讨了普通取心工艺钻进时采用岩心上升系数的实践意义,提出绳索取心工艺钻进时的“泄”、“堵”、“疏”的解决思路,形成了解决该矿区Ⅰa含矿层的坑道钻探施工难点的对策,以期为类似地层条件的坑道钻探提供技术指导。  相似文献   
62.
白云鄂博矿区土壤和植物中稀土元素的分布特征   总被引:2,自引:1,他引:1  
白云鄂博矿区是稀土的主要产出地,在矿山开采和选炼等过程中,稀土元素通过迁移、富集等作用进入植物体,研究稀土元素的分布特征和迁移规律,可为白云鄂博矿体闭坑后的生物修复提供数据支持。本文设置了7个土壤采样点,采集铁花、沙蒿、沙打旺、沙朋、青蒿、小叶杨、猪毛菜七种植物,用电感耦合等离子体质谱法测定土壤和植物的根、茎、叶及整株的稀土含量,研究稀土元素在土壤和植物中的分布特征和迁移规律。统计分析结果表明:随着采样区与主矿区的距离增加,土壤样品中的稀土含量逐渐减少;在七种植物中,铁花的稀土含量最高,青蒿最低;对不同植物的整株稀土含量和各部位(根、茎、叶)稀土含量进行多元线性回归分析,叶(或花)的稀土含量在整珠植物中的占比最大。此外在不同季节,植物中的稀土含量基本保持不变,含量较高的稀土元素为Ce(0.0035%~0.020%)、La(0.0012%~0.011%)、Nd(0.0010%~0.0094%)和Pr(0.00036%~0.0046%),其中Ce最高。本研究提出:根据土壤样品中的稀土含量逐渐减少的特征,矿区周围土壤的稀土来源可能是矿石在采、选过程中的扩散造成的;根据植物富集稀土的能力,在矿山闭坑后,可种植富集稀土能力强的植物——铁花,进行矿山生物修复。  相似文献   
63.
矿井涌水量预测对煤矿安全开采具有重要的指导依据。本文将锦东煤矿作为研究对象,利用地下水数值模拟软件MODFLOW建立数值模型,并对其进行识别验证,在合理可靠的模型基础上,对未开采和开采两种方案进行预测,对矿井涌水量组成进行分析。计算结果表明,锦东煤矿开采条件下,矿井涌水量为6 130 m3/d,主要由第四系潜水蒸发量、各泉集河溢流损失量和地下水储存量三部分组成。  相似文献   
64.
殷玉忠 《地下水》2019,(3):22-24
基于信湖煤矿水文地质条件,利用数值法和地下水动力学方法分别进行矿坑涌水量预测,并就预测结果进行对比分析,结果显示:利用数值模拟法预测得到的信湖矿的矿坑涌水量为11 000~3 236 m^3/d,水动力学方法得到的信湖矿的涌水量为13 152 m^3/d,两种预测方法所测算出的结果偏差不大,总体认为数值法的计算结果比较可靠。同时可将水动力学法当做数值法计算矿坑涌水量预测的一种检验印证方法,两种计算方法结合起来会使矿坑涌水量的预测结果更加准确。  相似文献   
65.
 Mining activity in the Boccheggiano-Fontalcinaldo area (Southern Tuscany) dates back at least to the 16th century AD and lasted up to very recent times. Copper-rich hydrothermal veins, massive pyrite deposits, and their gossans were exploited. Two mine waste dumps (Fontalcinaldo, Fontebona), one flotation tailings impoundment (Gabellino), and one roasting/smelting waste dump (Merse-Ribudelli) in the study area were selected to ascertain the environmental effects of such protracted mining activity. Primary waste mineralogy is mainly characterized by pyrite, gypsum, quartz, carbonates, chlorites, and micas. Secondary oxidation mineralogy includes Fe and Cu sulfates and hydroxy sulfates, Cu carbonates, Fe and Al oxyhydroxides, and other phases [neogenic cassiterite at Fontalcinaldo; probable calkinsite, (Ce,La)2(CO3)3· 4H2O, at Fontebona]. Mine waste samples show extremely variable contents of toxic elements (Cu, Pb, Zn, Bi, Cd, As), with average values in the order of hundreds to thousands of parts per million (except for Bi and Cd). In some samples, the abundance of proper minerals of these metals cannot account for the entire metal load. Conceivably, either solid solution substitutions or adsorption processes contribute to the intake of released metals into newly formed minerals. Release and transport of pollutants was affected to variable degrees by acid-neutralization processes. The highest metal and acid concentrations occur close to the investigated wastes and rapidly decrease moving downstream some hundreds of meters or less, with the partial exception for Mn and Fe. Other than dilution effects, this phenomenon may be ascribed to metal adsorption and precipitation of solid phases. Received: 16 April 1995 · Accepted: 14 December 1995  相似文献   
66.
Unlike the majority of the water in the flooded mine complex of Butte Montana, which includes the highly acidic Berkeley pit lake, groundwater in the flooded West Camp underground mine workings has a circum-neutral pH and contains at least 8 μM aqueous sulfide. This article examines the geochemistry and stable isotope composition of this unusual H2S-rich mine water, and also discusses problems related to the colorimetric analysis of sulfide in waters that contain FeS(aq) cluster compounds. The West Camp mine pool is maintained at a constant elevation by continuous pumping, with discharge water that contains elevated Mn (90 μM), Fe (16 μM), and As (1.3 μM) but otherwise low metal concentrations. Dissolved inorganic carbon in the mine water is in chemical and isotopic equilibrium with rhodochrosite in the mineralized veins. The mine water is under-saturated with mackinawite and amorphous FeS, but is supersaturated with Cu- and Zn-sulfides. However, voltammetry studies show that much of the dissolved sulfide and ferrous iron are present as FeS(aq) cluster molecules: as a result, the free concentration of the West Camp water is poorly constrained. Concentrations of dissolved sulfide determined by colorimetry were lower than gravimetric assays obtained by AgNO3 addition, implying that the FeS(aq) clusters are not completely extracted by the Methylene Blue reagent. In contrast, the clusters are quantitatively extracted as Ag2S after addition of AgNO3. Isotopic analysis of co-existing aqueous sulfide and sulfate confirms that the sulfide was produced by sulfate-reducing bacteria (SRB). The H2S-rich mine water is not confined to the immediate vicinity of the extraction well, but is also present in flooded mine shafts up to 3 km away, and in samples bailed from mine shafts at depths up to 300 m below static water level. This illustrates that SRB are well established throughout the southwestern portion of the extensive (>15 km3) Butte flooded mine complex.  相似文献   
67.
本文详细分析了黄金矿产地质勘查、矿山建设及金矿生产等阶段工作的特点及其相互关系,探索性地提出提前建矿,缩短探矿和建设周期的办矿方式,并就如何加快黄金发展步伐问题提出了几点思考。  相似文献   
68.
强度折减法在滑坡稳定性分析中的应用   总被引:3,自引:3,他引:0  
沁水县侯村煤矿边坡处治后,I~III段使用良好,IV段抗滑挡墙失效。本文采用有限元强度折减法计算,强度指标比原定的降低了1.29倍。同时,在折减过程中,通过计算分析剪应力集中部位,确定滑面是在老滑面的基础上发展的部分新滑面,形成新的剪出口。利用折减后强度参数,计算对比新滑面与次级滑面的滑坡推力,认为挡墙破坏为新滑面推力过大所致,与原设的“次级滑面为最危险滑面”情况不符,计算结果与实际情况较吻合。   相似文献   
69.
桃园煤矿10煤底板裂隙发育不均匀,合理确定钻孔注浆堵水有效半径,是10煤安全开采的保障。经理论计算和实验研究,确定注浆有效半径为1015 m。   相似文献   
70.
Attenuation of Heavy Metals and Sulfate by Aluminium Precipitates in Acid Mine Drainage During the mixing of acid mine waters with nearly neutral tributaries, often precipitates are formed which are high in iron or aluminium. These precipitates cover the river bed for many kilometres. Near the town of Lehesten (Thuringian slate mining area), leachates of slate quarries and waste rock dumps contain high amounts of aluminium, sulfate, copper, nickel, zinc, manganese, and H+ ions as a result of the oxidation of incorporated pyrite. These leachates enter the brooks Loquitz, Kleine Sormitz, and Rehbach leading to the phenomenon named above. The contribution of the forming aluminium‐rich precipitates on the attenuation of sulfate and heavy metals by sorption or coprecipitation was studied by analysing the composition of water and sediment samples as well as samples of suspended matter. Sulfate is often considered as conservative tracer in acid mine drainage. However, sulfate does not behave conservatively in this system what might be explained by the adsorption of sulfate to the aluminium precipitates. Instead, conservative behaviour was found for calcium, potassium, chloride, zinc, manganese, and nickel. A formation of jurbanite can be excluded because of the low sulfate contents. The sulfate content of the sediment depends on the pH. At low pH values (4.8) the S/Al ratio corresponds to the theoretical ratio in basaluminite and decreases with rising pH. Sulfate is weakly bound to the solid phase and can easily be replaced by OH ions. A formation of basaluminite is possible at low pH values with a fluent transition to aluminium hydroxide. Therefore the precipitates are assumed to consist predominantly of aluminium hydroxide with sulfate being adsorbed to the surface.  相似文献   
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