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121.
根据紫金山铜矿的实际情况,分析采用原地破碎细菌浸出工艺回收紫金山铜矿资源的工程技术可行性,在此基础上进行经济方面的讨论。 相似文献
122.
地浸采铀矿山地下水污染碱性中和清洗法治理研究 总被引:1,自引:0,他引:1
地浸采矿方法可引起地下水环境的严重污染,文章对地下水污染过程及治理机理进行了阐明,针对地浸铀矿山的污染特点,提出了碱性中和清洗治理方法的设想,并对碱性中和清洗法治理地浸铀矿山的地下水环境污染的方法及治理效果进行了实验研究,采用水文地球化学模式PHREEQC1.6来模拟计算中和清洗液的最佳pH值,提出了对现场清洗治理具有重要意义的一个重要指标——清洗比,实验结果表明,碱性中和清洗法对治理地浸矿山的地下水污染治理效果明显.为我国地浸矿山地下水污染治理工作的开展进行了探索性研究。 相似文献
123.
Visnja Orescanin Delko Barisic Ivanka Lovrencic Luka Mikelic Martina Rozmaric-Macefat Gordana Pavlovic Stipe Lulic 《Environmental Geology》2005,49(1):53-64
The objective of this study was chemical and radiological characterization of Kastela Bay sediments exposed to numerous anthropogenic sources like deposition of fly and bottom ash enriched in radionuclides and heavy metals, chemical plant, cement plant, iron plant, shipyard, electroplating facility, untreated industrial and domestic waste waters as well as heavy traffic. Totally, 33 samples of the mixture of fly and bottom ash, 12 sediment cores ranging from 0 to 40 cm and nine surface sediment samples were analyzed. Enrichment in heavy metals in the mixture of fly and bottom ash was ranging from 1.5 to 36 times compared to flysch soil while 226Ra and 238U were up to 50 times enriched compared to average activities characteristic for surrounding soils developed on the Middle and Upper Eocene flysch. Maximum 238U activity was approximately 32 times higher and 226Ra approximately 40 times higher in the Kastela Bay sediment compared to mean value determined for Adriatic sediments. The highest enrichment in sediment cores compared to background values were found for Zn (35.6 times), Pb (16 times), Cr (9.1 times) and Ni (4 times) 相似文献
124.
层间氧化作用成因的砂岩型卷状铀矿床的原地浸出已在我国北方成功开展多年,对我国铀矿事业产生了巨大的影响,但由于卷状矿体的卷头和翼部矿体物质成份及赋存环境的差异,目前以开采卷头矿体为主,而翼部矿体因技术和经济因素未被开采利用,造成资源的较大浪费.因此从翼部矿体成因入手,展开理论分析和实际采样研究的尝试工作,从倾向和垂向上仔细研究翼部矿体铀矿物成份及铀元素价态变化特征,得出翼部矿体与卷头矿体铀元素价态有所不同,但经过预氧化过程翼部矿体完全可以像卷头一样较易浸出的结论,并且给出了相应的浸出建议方法. 相似文献
125.
Metal mobility at contaminated sites can be assessed by soil water investigations or by leaching tests. Leaching tests are usually carried out in open contact with the atmosphere disregarding possible changes of redox conditions. This can affect the original metal speciation and distribution, particularly when anoxic samples are investigated. In this study, the applicability of common leaching tests (the German S4 test (S4), ammonium nitrate extraction (AmmN), and saturation soil extraction (SSE)) is tested for the assessment of zinc release from sulfide‐bearing flotation residues of a former ore mine. Results are compared to soil solution samples obtained by centrifugation and suction cups. The influence of sample storage on S4 leaching test results is investigated in a long‐term study to assess oxidation kinetics. Within the first 200 days the release of zinc increases with a slope of 0.1 mmol kg–1 d–1 or 6.0 mg kg–1 d–1, respectively. Since oxidation of the sulfide‐bearing samples leads to a significant overestimation of metal release, a feasible modification for the conduction of leaching tests for anoxic material is proposed where oxidation is prevented efficiently. The modified SSE is found to be the only of the tested leaching procedures, which can be recommended for the assessment of current soil water concentrations at anoxic sites if direct investigation of the soil water is impossible due to technical reasons. 相似文献
126.
文章论述了长城堡岩体西段放射性水文地质特征、水化学异常特征和铀矿化特征,探讨了三者之问的相关关系;指出该区铀矿化受水化学异常区和水文地球化学垂直分带的控制,铀主要富集在氧化-还原过渡带;根据该区铀易浸出的特点,认为适合于用溶浸和地浸法开采。 相似文献
127.
原地破碎浸出试验时溶浸液垂向入渗过程的数据模拟 总被引:2,自引:1,他引:1
本文通过原地破碎浸出试验时溶浸液运动规律的分析,将溶浸过程中溶浸液的运动分为非饱和带内垂向入渗和饱和带内水平向径流两个主要阶段,并建立其相应的数学模型,还对溶浸液的垂向入渗过程进行了数值模拟。 相似文献
128.
129.
Enzyme leach anomalies associated with deep Mississippi Valley-type zinc ore bodies at the Elmwood Mine, Tennessee 总被引:1,自引:0,他引:1
James R. Yeager J. Robert Clark Wallace Mitchell Roy Renshaw 《Journal of Geochemical Exploration》1998,61(1-3)
Deeply buried Mississippi Valley-type deposits that have been or are currently being mined in North America were initially discovered by drilling. Conventional geochemical methods are ineffective for detecting these ‘blind' deposits when they occur deep within sequences of stable-platform carbonates and shales. The ‘enzyme' leach is a selective analytical technique for determining trace elements associated with amorphous Mn oxide coatings in soils. In many areas of the world, the enzyme leach method is useful for detecting low-level geochemical anomalies in soils, which are associated with blind mineral deposits. Enzyme leach analysis of soils, collected at the Elmwood Mine, Tennessee, revealed high-contrast anomalies over ore bodies 370 m below the surface. In areas where the soils are in chemical equilibrium, ‘combination' anomalies occur over Zn ore bodies. These are characterized by asymmetrical halogen halos which occur around a halogen ‘central low'. Commodity metals (Zn and Pb) and trace elements associated with the ore (Cd, Ba, and Mn) form apical anomalies, which occur over the ore bodies and within the halogen halo. Under most circumstances, agricultural practices do not affect enzyme leach results. However, agricultural activity in central Tennessee appears to have altered the proportion of amorphous Mn oxides in the soils in some locations. Where the MnO2-form equilibrium of the soil has been disturbed, enzyme leach data are erratic. In the one instance where this was encountered, ratioing the data to Mn reveals anomalies which bracket the blind ore bodies. 相似文献
130.
评价可地浸硬岩铀矿床的主要依据 总被引:2,自引:0,他引:2
作者根据国内外进行铀矿床原地破碎浸出工业试验的研究成果,总结了判别硬岩铀矿床能否适于地浸的主要依据,内容包括矿石的破碎性能、矿石的浸出性能、矿石的渗透性及围岩的透水性。并认为只有在全面分析与主要判据有关的矿床地质因素、水文地质因素的基础上,才能从技术可行性方面分析矿床能否适于地浸。 相似文献