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91.
靳国齐 《华北地质矿产杂志》1999,(2)
面对我们生存环境日趋恶化的现状,加快对矿山污染问题的解决已成当务之急。本文从提高对环境、生态系统的认识入手,提出用生态工艺解决矿山污染工作的办法。采矿、选矿使用生态工艺(闭路循环工艺),使矿业活动的固体废弃物──围岩、废矿石、尾矿石建鱼鳞坑、梯田埂。实现“环境补偿”,从而提高了环境的自净能力,使矿业得以持续稳定地发展。 相似文献
92.
Sudhakar M. Rao B. V. Venkatarama Reddy 《Geotechnical and Geological Engineering》2006,24(6):1545-1559
The gold mining process at Kolar gold field (KGF) mines has generated about 32 million tons of tailings. Gold was extracted
from the mined ores using cyanidation technique that involved dissolution of gold in the ore by water soluble alkali metal
cyanides (example, sodium cyanide or potassium cyanide). Of the several dumps that received the mine tailings only the Kennedy’s
Line dump was active prior to closure of the KGF mines in the year 2000. The Kennedy’s Line dump received sulfide bearing
tailings in slurry form that comprised of spent ore and process water bearing soluble alkali metal cyanide. Depending on the
pH of the tailing slurry, the free cyanides may exist as aqueous hydrogen cyanide that can escape to the atmosphere as hydrogen
cyanide gas or occur as soluble cyanide (CN−) ions that can be leached by infiltrating water to the sub-surface environment. Additionally, the presence of pyrite minerals
in the Kennedy’s Line dump makes them susceptible to acid drainage. This study examines the potential of gold tailings of
Kennedy’s Line dump to release cyanide ions (CN−) and acid drainage to the sub-surface environment by performing physico-chemical and leaching tests with tailing samples
collected from various depths of the dump, sub-surface soil samples beneath the dump and groundwater samples from vicinity
of Kennedy’s Line dump. The chemical mechanisms responsible for the ambient cyanide and pH levels of the tailing dump, sub-surface
soil samples and groundwater are also inferred from the laboratory results. 相似文献
93.
Based on a case study on uranium mine No.765 of China National Nuclear Corporation (CNNC), the paper briefly describes disposal program and effect of decommissioning uranium mine/mill facilities and quantitatively evaluates radon fluxes and doses to man of gaseous airborne pathway from mill tailings and mining debris before and after decommissioning, including annual individual effective dose to critical groups and annual collective effective dose to the population within 80 km region of the facilities. 相似文献
94.
After placement of cemented tailings backfill (CTB), which is a mixture of tailings (man‐made soil), water, and binder, into underground mined‐out voids (stopes), the hydration reaction of the binder converts the capillary water into chemically bound water, which results in the reduction of the water content in the pores of the CTB, thereby causing a reduction in the pore‐water pressure in the CTB (self‐desiccation). Self‐desiccation has a significant impact on the pore‐water pressure and effective stress development in CTB and paramount and practical importance for the stability assessment and design of CTB structures and barricades. However, self‐desiccation in CTB structures is complex because it is a function of the multiphysics or coupled (i.e., thermal, hydraulic, mechanical, and chemical) processes that occur in CTB. To understand the self‐desiccation behavior of CTB, an integrated multiphysics model of self‐desiccation is developed in this study, which fully considers the coupled thermal, hydraulic, mechanical, and chemical processes and the consolidation process in CTB. All model coefficients are determined in measurable parameters. Moreover, the predictive ability of the model is verified with extensive case studies. A series of engineering issues are examined with the validated model to investigate the self‐desiccation process in CTB structures with respect to the changes in the mixture recipe, backfilling, and the surrounding rock and curing conditions. The obtained results provide in‐depth insight into the self‐desiccation behavior of CTB structures. The developed multiphysics model is therefore a potential tool for assessing and predicting self‐desiccation in CTB structures. 相似文献
95.
Shallow marine sediments and fringing coral reefs of the Buyat-Ratototok district of North Sulawesi, Indonesia, are affected by submarine disposal of tailings from industrial gold mining and by small-scale gold mining using mercury amalgamation. Between-site variation in heavy metal concentrations in shallow marine sediments was partially reflected by trace element concentrations in reef coral skeletons from adjacent reefs. Corals skeletons recorded silicon, manganese, iron, copper, chromium, cobalt, antimony, thallium, and lead in different concentrations according to proximity to sources, but arsenic concentrations in corals were not significantly different among sites. Temporal analysis found that peak concentrations of arsenic and chromium generally coincided with peak concentrations of silica and/or copper, suggesting that most trace elements in the coral skeleton were incorporated into detrital siliciclastic sediments, rather than impurities within skeletal aragonite. 相似文献
96.
Three tests of slurried Jeeropilly coal tailings in a purpose-built slurry consolidometer under three different loading sequences were numerically analysed to study the friction losses quantitatively. A simplified sedimentation-consolidation theory was proposed to link the initial suspended state and soil-like state of slurries. The numerical simulations provided good agreement with the measured, and indicated the noticeable friction losses, from 11.1% to 34.2%, due to factors such as the diameter of consolidometers and loading sequences. The average coefficient of the stress (pore water pressure) stood at 1 at the beginning, and declined to a stable value around 0.55 (0.67). 相似文献
97.
为探讨富硫化物尾矿酸化及重金属污染特征,选择安徽铜陵水木冲尾矿库浅层(0~90 cm)剖面为研究对象,对其结构特点、矿物组成、重金属(Pb、Cd、Zn、Ni、Cr、Mn、Cu和As)含量及赋存形态进行研究。结果表明,该尾矿库浅层出现分层现象,即表层为强硬化层,向下依次为弱硬化层和松散层,且呈酸性;矿物主要以辉石、长石、云母和石膏为主,由浅及深,金属硫化物及碳酸盐型矿物特征峰呈现增强的趋势;重金属呈现两种富集类型:表层(0~30cm,As、Pb)富集和中部(40~60 cm,Cd、Cu、Mn、Ni、Zn和Cr)富集型,其中Cu、Cd、As污染较为严重。由相关性分析可知,部分金属之间存在一定的伴生性,且p H值是影响重金属迁移的重要因素之一。该尾矿重金属主要以残渣态为主,其中Pb的潜在迁移能力最强,As最弱,顺序为Pb Cd Zn Ni Cr Mn Cu As。 相似文献
98.
含水率影响下尾矿砂内摩擦角随标贯击数变化研究 总被引:1,自引:0,他引:1
尾矿砂样品在运输和存放过程中均存在易扰动的特点,但考虑到工程造价以及人力资源等因素,目前在大部分上游式尾矿坝的工程地质勘察中难以建立现场试验室,所得抗剪强度指标与实际情况存在一定误差。针对这种现状,结合某铅锌矿尾矿坝现场试验结果,从现场简易试验获得的含水率和标准贯入击数进行分析,并对基于含水率影响下尾矿砂内摩擦角随标准贯入击数变化规律进行了研究,提出了考虑上覆压力作用下标准贯入击数的修正公式,并推出了用标准贯入击数估算尾矿砂内摩擦角的方法。通过几个实例验证:除当修正后的标准贯入击数N1>8(5%< <20%)情况下以外,该方法均能够有效地估算尾矿砂内摩擦角。研究结果表明,该方法在以后的上游式尾矿堆积坝的工程地质勘察工作中具有较强的应用价值。 相似文献
99.
Both froth flotation and centrifugal concentration were used to pre-concentrate the oil sands froth treatment tailings prior to the recovery of heavy minerals (titanium and zirconium minerals). Over 90% of the heavy minerals were recovered into a bulk flotation concentrate that was about 50% of the feed mass at 85 °C without any reagents. The same recoveries were obtained at 50 °C with the addition of NaOH and/or sodium oleate. However, the flotation concentrate also recovered over 90% of the residual bitumen and much of the clays/slimes. Subsequent treatment of the flotation concentrate such as dewatering and bitumen removal would be difficult due to these residual bitumen and clays. On the other hand, a SB40 centrifugal concentrator recovered over 85% of the heavy minerals but less than 30% of the residual bitumen. With improved liberation the recovery of the residual bitumen into the concentrate could be further reduced. The particle sizes of the SB40 concentrates were also larger than the flotation concentrates, making subsequent processing much easier. 相似文献
100.