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Sample records for carlin-type ore sample

  1. Ore fluid geochemistry of the Jinlongshan Carlin type gold ore belt in Shaanxi Province, China

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The Jinlongshan gold ore belt in southern Shaanxi Province contains a number of Carlin-type gold deposits in the Qinling collisional orogenic belt. Their fluid inclusions are of the Na+ - Cl- type. From the main metallogenic stage to later stages, the total quantity of anions and cations, temperature and deoxidation parameter (R) for fluid inclusions all gradu ally decreased, suggesting the gradual intensification of fluid oxidation, the reduction of met allogenic depth and the input of meteoric water and organic components. The deposits were formed during crustal uplifting and hence had similar tectonic settings to orogenic gold depos its. The CO2 contents and CO2/H2O values of the ore fluid increased from early to late sta ges, and the wall-rock alteration is represented by decarbonation, which is inconsistent with the characteristics of orogenic gold deposits. It is also discovered that Na + , K + ,SO42-, Cl-and the total amounts of anions and cations in the inclusions in quartz are higher than those in the coexisting calcite. The H, O and C isotope ratios indicate that the ore fluid was sourced from meteoric water and metamorphic devolatilisation of the sedimentary rocks that host the ores. The high background δ18O and δ13C values of wall rocks resulted in high δ18O and δ13 C values of ore fluid and also high δ 18 O and δ 13 C values of hydrothermal minerals such as quartz and carbonate. The carbon in ore fluid stemmed largely from the hosting strata. The δ 18O and δ13C values of Fe-calcite and the δD values of fluid inclusions are lower than those of calcite and quartz. In terms of the theory of coordination chemistry, all these differences can be ascribed to water-rock interaction in the same fluid system, instead, to the multi source of ore fluid.

  2. Research on gold extraction from a carlin-type oxide gold ore in Gansu%甘肃某卡林型氧化金矿石回收金试验研究

    Institute of Scientific and Technical Information of China (English)

    缑明亮; 崔长征

    2012-01-01

    甘肃某卡林型氧化金矿石中金以微细粒包裹赋存在硫化矿、氧化铁矿、碳酸盐、硅酸盐等矿物中,采用全泥氰化和浮选工艺处理,金回收率很低.通过探索试验,确定采用焙烧—氰化工艺处理,在试验确定的最优条件下,金氰化浸出率可达到92%,取得了理想试验指标.%Oxide gold ores in this carlin-type gold deposit in Gansu province occur in superfine form embeded in sulfide ores,ferrous oxide ores,carbonate,silicate and so on.Poor gold recovery is only to be achieved when all sliming cyanidation and flotation are applied.Through exploratory experiments,a process of roasting-cyanidation is selected,in which,under optimisedconditions,gold recovery can reach 92 %.

  3. Trace Elements in Fluid Inclusions in the Carlin-Type Gold Deposits, Southwestern Guizhou Province

    Institute of Scientific and Technical Information of China (English)

    苏文超; 胡瑞忠; 漆亮; 方维萱

    2001-01-01

    Fluid inclusions in quartz from the Lannigou and Yata Carlin-type gold deposits in southwestern Guizhou were analyzed by inductively coupled plasma-mass spectrometry for their trace elements (Co, Ni, Cu, Pb, Zn, Pt, etc. ). The results show that quartz fluid inclusions entrapped at different ore-forming stages contain higher Co, Ni, Cu, Pb and Zn. It has been found for the first time that the ore-forming fluids responsible for the Carlin-type gold deposits are rich in Pt. From this it can be concluded that basic volcanic rocks seem to be one of the im portant sources of ore-forming materials for the Carlin-type gold deposits.

  4. Geological and geochemical character and genesis of the Jinlongshan-Qiuling gold deposits in Qinling orogen: Metallogenic mechanism of the Qinling-pattern Carlin-type gold deposits

    Institute of Scientific and Technical Information of China (English)

    张复新,陈衍景,李超Department; of; Geology,; Peking; University,; Beijing; 100871,; China; ,张静Department; of; Geology,; Peking; University,; Beijing; 100871,; China; ,马建秦,李欣Department; of; Geology,; Peking; University,; Beijing; 100871,; China

    2000-01-01

    The Qinling Carlin-type gold deposit belt is the second largest Carlin-type gold ore concentrated area in the world and occurs in Mesozoic intracontinental collisional orogen, contrasting to the Carlin-type gold deposits in the Basin and Range province in Cenozoic active continental margin of West America. With ore-forming ages focussed at the range of 197.45-129.45 Ma, its metallogenic geodynamic background was the decornpression-pyrogenation regime at the transition stage from collisional compression to extension, indicating that gold mineralization synchronized with the Mesozoic continental collision. Geochemical studies discover that ore fluids and materials mainly came from the Hercynian-lndosinian tectonic layer. Mesozoic intracontinental subduction of Hercynian-lndosinian association along the Shuanghe-Gongguan fault led to the formation of Jinlongshan-Qiuling gold deposits. Accordingly, the tectonic metallogenic model is established for Qinling-pattern Carlin-type gold deposits.

  5. Comparison of the native antimony-bearing Paiting gold deposit, Guizhou Province, China, with Carlin-type gold deposits, Nevada, USA

    Science.gov (United States)

    Xie, Zhuo-Jun; Xia, Yong; Cline, Jean S.; Yan, Bao-Wen; Wang, Ze-Peng; Tan, Qin-Ping; Wei, Dong-Tian

    2017-01-01

    The Paiting gold deposit, Guizhou Province, China, has been regarded as a Carlin-type gold deposit by several researchers. Alteration and ore-related minerals from the Paiting deposit were examined, and results were compared with the Cortez Hills Carlin-type gold deposit, Nevada, USA. Similarities include the structural and stratigraphic controls on the orebodies in both deposits and the occurrence of invisible gold ionically bound in arsenian pyrite. Significant differences include the following: (1) The gold-bearing mineral in Nevada is arsenian pyrite. However, gold-bearing minerals in the Paiting deposit include arsenopyrite, arsenian pyrite, and trace pyrrhotite. Also, euhedral or subhedral gold-bearing arsenian pyrite at Paiting contains significantly less As, Cu, and Hg than gold-bearing pyrite from Nevada. (2) Alteration in the Paiting deposit displays significantly less decarbonatization. Instead, dolomite precipitation, which has not been described in Nevada deposits, is associated with deposition of gold-bearing sulfide minerals. (3) Stibnite and minor native antimony typify Paiting late-ore-stage minerals, whereas in Nevada, realgar, orpiment, and calcite are common late-ore-stage minerals. Precipitation of native antimony in the Paiting deposit reflects the evolution of a late-ore fluid with unusually low sulfur and oxygen fugacities. Some characteristics of the Paiting gold deposit, including formation of ore-stage dolomite and precipitation from CO2-rich ore fluids at temperatures in excess of 250 °C, are more typical of orogenic deposits than Nevada Carlin deposits. The presence of similarities in the Paiting deposit to both Carlin type and orogenic deposits is consistent with formation conditions intermediate to those typical of Carlin type and orogenic systems.

  6. A Comparison of Carlin-type Gold Deposits: Guizhou Province, Golden Triangle, Southwest China, and Northern Nevada, USA%A Comparison of Carlin-type Gold Deposits:Guizhou Province,Golden Triangle,Southwest China,and Northern Nevada,USA

    Institute of Scientific and Technical Information of China (English)

    Jean S.CLINE; John L.MUNTEAN; Xuexiang GU; Yong XIA

    2013-01-01

    Several Au deposits in Guizhou Province,southwest China,described as being similar to the highly productive Carlin-type gold deposits in northern Nevada,USA,were examined to identify similarities and differences between the two districts.Samples were collected along transects from lowto high-grade rock,where possible,and from stockpiles at the Shuiyindong,Zimudang,Taipingdong,Yata and Jinfeng (formerly Lannigou) deposits.Methods used to examine ore and alteration minerals included hand-sample description; reflectance spectroscopy using an ASD Terraspec spectrometer;analyses of hand samples by carbonate staining with Alizaren red and potassium ferricyanide;transmitted and reflected light petrography; chemical analyses,mineral identification,and imaging using a JEOL JSM-5610 scanning electron microscope; and quantitative chemical analyses using a JEOL JXA-8900 electron probe microanalyzer.Geochemical analyses of hand samples for 52 elements were done by ALS Chemex.Results indicate both similarities and differences between the two districts.Both districts have similar geologic histories,and deposits at both locations appear to have formed as a result of similar tectonic events,though the district in southwest China lacks evidence of coeval felsic igneous activity;however,the ore-stage minerals and the fluids that produced the minerals and deposits have some significant differences.The Nevada deposits were dominated by fluid-rock reaction in which host rock Fe was sulfidized to form Au-bearing pyrite.Although ore fluids sulfidized host rock Fe in the Guizhou deposits,the timing of Fe metasomatism is unknown,so whether the deposits formed in response to sulfidation or pyritization is unclear.Fluid-rock reaction between an acidic,aqueous fluid and highly reactive calcareous rocks in Nevada caused extensive decarbonatization of host rocks,jasperoid replacement of carbonate minerals,and alteration of silty rock components to illite and kaolinite.In Guizhou,CO2-bearing ore

  7. Oreshoot zoning in the Carlin-type Betze orebody, Goldstrike Mine, Eureka County, Nevada

    Science.gov (United States)

    Peters, Stephen G.; Ferdock, Gregory C.; Woitsekhowskaya, Maria B.; Leonardson, Robert; Rahn, Jerry

    1998-01-01

    Field and laboratory investigations of the giant Betze gold orebody, the largest Carlin-type deposit known, in the north-central Carlin trend, Nevada document that the orebody is composed of individual high-grade oreshoots that contain different geologic, mineralogic, and textural characteristics. The orebody is typical of many structurally controlled Carlin-type deposits, and is hosted in thin-bedded, impure carbonate or limy siltstone, breccia bodies, and intrusive or calc-silicate rock. Most ores in the Betze orebody are highly sheared or brecciated and show evidence of syndeformational hydrothermal deposition. The interplay between rock types and pre- and syn-structural events accounts for most of the distribution and zoning of the oreshoots. Hydrothermal alteration is scale dependent, either in broad, pervasive alteration patterns, or in areas related to various oreshoots. Alteration includes decarbonatization (~decalcification) of carbonate units, argillization (illite-clay), and silicification. Patterns of alteration zoning in and surrounding the Betze orebody define a large porous, dilated volume of rock where high fluid flow predominated. Local restriction of alteration to narrow illite- and clay-rich selvages around unaltered marble or calc-silicate rock phacoids implies that fluid flow favored permeable structures and deformed zones. Gold mainly is present as disseminated sub-micron-sized particles, commonly associated with Asñrich pyrite, although one type of oreshoot contains micron-size free gold. Oreshoots form a three-dimensional zoning pattern in the orebody within a WNW-striking structural zone of shearing and shear folding, termed the Dillon deformation zone (DDZ). Main types of oreshoots are: (1) rutile-bearing siliceous oreshoots; (2) illite-clay-pyrite oreshoots; (3) realgar- and orpiment-bearing oreshoots; (4) stibnite-bearing siliceous oreshoots; and (5) polymetallic oreshoots. Zoning patterns result from paragenetically early development

  8. A study on the genetic relations between Permian Longtan Formation coal series strata and Carlin-type gold deposits, southwestern Guizhou Province, China

    Institute of Scientific and Technical Information of China (English)

    NIE Aiguo; MEI Shiquan; GUAN Daiyun; WU Pan; ZHANG Zhuru

    2008-01-01

    A large number of the Carlin-type gold deposits occur in the Longtan Formation in southwestern Guizhou Province. The Longtan Formation contains abundant basalt, tuff and siliceous rocks. All rocks of the Longtan Formation are enriched in gold, which were deposited in a limited platform environment in the transition zone from marine to continental. The process of sedimentation was accompanied by the eruption of Emeishan basalt and hydrothermal deposition controlled by co-sedimentary submarine deep faults in the west, which led to the formation of a peculiar gold-bearing formation with coal series strata. This formation controlled the occurrence of the Carlin-type gold deposits in southwestern Guizhou Province. In response to the remobilization of the Emei mantle plume during the Yanshanian period, As, Au and other ore-forming materials were continuously extracted by deeply circulating waters from the Emeishan basalt and coal seams, thereafter forming ore-forming hydrothermal solutions.When these elements were transported in the coal seams, large amounts of As, Au and other elements were enriched in pyrite within the coal seams, thus forming high-As coal and Carlin-type gold deposits in the Longtan Formation coal series strata.

  9. Geochemical Study of Gold and Arsenic Mineralization of the Carlin-Type Gold Deposits, Qinling Region, China

    Institute of Scientific and Technical Information of China (English)

    张复新; 马建秦; 陈衍景

    2001-01-01

    Element geochemistry of gold and arsenic and mineralogical features of their sulfides in the Carlin-type gold deposits of the Qinling region are discussed in this paper. The initial contents of ore-forming elements such as gold and arsenic are high in the ore-bearing rock series in the Qinling region. Furthermore, both the metals are concentrated mainly in the diagenetic pyrite. Study on the mineralogy of arsenic-bearing sulfide minerals in the ores demonstrated that there is a positive correlation between gold and arsenic in the sulfide minerals. Available evidence suggests that gold in the As-bearing sulfide minerals is likely to be presented as a charge species (Au + ), and it is most possible for it to replace the excess arsenic at the site of iron and was probably deposited together with arsenic as solid solution in the sulfide minerals.Pyrite is composed of (Au3x+, Fe12-+ x) ([AsS]3x- [S2]12--x), and arsenopyrite of (Au3x+ , Fe13-+x)([AsS]3x- [AsS2 ]1-3-x). The occurrence of gold in the As-sulfide minerals from the Carlin-type gold deposits in the Qinling region has been confirmed by electron probe and transmission elec tron microscopic studies. The results show that gold was probably deposited together with ar senic as coupled solid solutions in sulfide minerals in the early stage of mineralization. Metallo genic chemical reactions concerning gold deposition in the Carlin-type As-rich gold deposits would involve oxidation of gold and concurrent reduction of arsenic. Later, the deposited gold as solid solution was remobilized and redistributed as exsolutions, as a result of increasing hy drothermal alteration and crystallization, and decreasing resistance to refractoriness of the host minerals. Gold occurs as sub-microscopic grains (ranging from 0.04 to 0.16 μm in diameter)of native gold along micro factures in and crystalline grains of the sulfides.

  10. Structural controls on Carlin-type gold mineralization in the gold bar district, Eureka County, Nevada

    Science.gov (United States)

    Yigit, O.; Nelson, E.P.; Hitzman, M.W.; Hofstra, A.H.

    2003-01-01

    The Gold Bar district in the southern Roberts Mountains, 48 km northwest of Eureka, Nevada, contains one main deposit (Gold Bar), five satellite deposits, and other resources. Approximately 0.5 Moz of gold have been recovered from a resource of 1,639,000 oz of gold in Carlin-type gold deposits in lower plate, miogeoclinal carbonate rocks below the Roberts Mountains thrust. Host rocks are unit 2 of the Upper Member of the Devonian Denay Formation and the Bartine Member of the McColley Canyon Formation. Spatial and temporal relations between structures and gold mineralization indicate that both pre-Tertiary and Tertiary structures were important controls on gold mineralization. Gold mineralization occurs primarily along high-angle Tertiary normal faults, some of which are reactivated reverse faults of Paleozoic or Mesozoic age. Most deposits are localized at the intersection of northwest- and northeast-striking faults. Alteration includes decalcification, and to a lesser extent, silicification along high-angle faults. Jasperoid (pervasive silicification), which formed along most faults and in some strata-bound zones, accounts for a small portion of the ore in every deposit. In the Gold Canyon deposit, a high-grade jasperoid pipe formed along a Tertiary normal fault which was localized along a zone of overturned fault-propagation folds and thrust faults of Paleozoic or Mesozoic age.

  11. Lithogeochemistry of Carlin-type gold mineralization in the Gold Bar district, Battle Mountain-Eureka trend, Nevada

    Science.gov (United States)

    Yigit, O.; Hofstra, A.H.

    2003-01-01

    The Gold Bar district contains five Carlin-type gold deposits and four resources for a combined gold endowment of 1.6 M oz [50 t]. The gold deposits are hosted in Devonian carbonate rocks below parautochthonous and allochthonous Paleozoic siliciclastic rocks emplaced during the Early Mississippian Antler orogeny. The district is in the Battle Mountain-Eureka trend, a long-lived structural feature that localized intrusions and ore deposits of different types and ages. The whole-rock geochemistry of four different mineralized and unmineralized Devonian carbonate rock units (two favorable and two unfavorable) were determined and interpreted in the context of the regional geology. A combination of basic statistics, R-mode factor analysis, isocon plots, and alteration diagrams were utilized to (1) identify favorable geochemical attributes of the host rocks, (2) characterize alteration and associated element enrichments and depletions, and (3) identify the mechanism of gold precipitation. This approach also led to the recognition of other types of alteration and mineralization in host rocks previously thought to be solely affected by Carlin-type mineralization. Unit 2 of the Upper Member of the Denay Formation, with the highest Al2O3, Fe2O3 and SiO2 contents and the lowest CaO content, is the most favorable host rock. Based on the high regression coefficients of data arrays on X-Y plots that project toward the origin, Al2O3 and TiO2 were immobile and K2O and Fe2O3 were relatively immobile during alteration and mineralization. Specific element associations identified by factor analysis are also prominent on isocon diagrams that compare the composition of fresh and altered equivalents of the same rock units. The most prominent associations are: Au, As, Sb, SiO2, TI, -CaO and -LOI, the main gold mineralizing event and related silicification and decalcification; Cd, Zn, Ag, P, Ni and Tl, an early base metal event; and MgO, early dolomitization. Alteration diagrams

  12. Carlin-Type Gold Deposits in Qinling and Some Related Problems

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The sediment-hosted disseminated gold deposits in the Oinling region are of sedimentation-slight-metamorphic origin superimposed by hydrothermal reworking at moderate-low temperatures and are well comparable with the typical Carlin gold deposits in the United States.In view of the confusing concept concerning the “sediment-hosted”and “Carlin-type” gold deposits,the authors propose that the term“sediment-hosted gold deposit”should be used in a broad sense which encompasses at least the four subtypes,i.e.,the Carlin type,the metamorphic fine clastic type,the hydrothermal sedimentary type and the vein type.In oter words,the “Carlin-type”should not be used as a synonym for “sediment-hosted”but is recommended as a subtype under the general category of “sediment-hosted gold deposits”

  13. A special issue devoted to gold deposits in northern Nevada: Part 2. Carlin-type Deposits

    Science.gov (United States)

    Hofstra, Albert H.; John, David A.; Theodore, Ted G.

    2003-01-01

    This is the second of two special issues of Economic Geology devoted to gold deposits in northern Nevada. Readers interested in a general overview of these deposits, their economic significance, their context within the tectonic evolution of the region, and synoptic references on each gold deposit type are directed to the preface of the first special issue (John et al., 2003). Volume 98, issue 2, contains five papers that address regional aspects important to the genesis of gold deposits in northern Nevada and five papers that present detailed studies of epithermal deposits and districts. All of the regional papers are pertinent to Carlin-type gold deposits, because they address the age of mineralization (Arehart et al., 2003), origin and evolutionary history of the northwest-striking mineral belts that localize many deposits (Grauch et al., 2003), nature of the middle and lower crust below these mineral belts (Howard, 2003), district- to deposit-scale stream sediment and lithogeochemical anomalies (Theodore et al., 2003), and stratigraphy and structure of a district located along a northeast-striking lineament (Peters et al., 2003).

  14. Gamma Spectrometric Analysis of Iron Ore Samples of Arak, Iran

    Directory of Open Access Journals (Sweden)

    Reza Pourimani

    2016-09-01

    Full Text Available Introduction Iron ore is one of the most important natural raw materials that is widely used for manufacturing iron and steel. This type of ore contains various amounts of radionuclides; thus, exposing workers handling their extraction, transportation, and processing to radiation. Materials and Methods In this study, 12 ore samples (each mass weighing about 2 kg were collected from the iron ore mining areas of Arak region, Iran. The specific activities of 226Ra, 232Th, and 40K were determined usinggamma-ray spectrometry method employing high-purity germanium (HPGe detector. Results The specific activities of 226Ra, 232Th, and 40K in samples were 9.39-271.70 Bq/kg, -3 Sv/y suggested in International Commission of Radiological Protection (ICRP Publication 82. Conclusion The gamma ray spectrometric analysis showed that the specific activities of natural radionuclides in samples, except for limonite ore, were within the worldwide range. The effective dose received by workers was much lower than the maximum acceptable value (1000 μSv/y; therefore, the level of radiations in this mine had no adverse consequences for public health.

  15. Standard practices for sampling uranium-Ore concentrate

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 These practices are intended to provide the nuclear industry with procedures for obtaining representative bulk samples from uranium-ore concentrates (UOC) (see Specification C967). 1.2 These practices also provide for obtaining a series of representative secondary samples from the original bulk sample for the determination of moisture and other test purposes, and for the preparation of pulverized analytical samples (see Test Methods C1022). 1.3 These practices consist of a number of alternative procedures for sampling and sample preparation which have been shown to be satisfactory through long experience in the nuclear industry. These procedures are described in the following order. Stage Procedure Section Primary Sampling One-stage falling stream 4 Two-stage falling stream 5 Auger 6 Secondary Sampling Straight-path (reciprocating) 7 Rotating (Vezin) 8, 9 Sample Preparation 10 Concurrent-drying 11-13 Natural moisture 14-16 Calcination 17, 18 Sample Packaging 19 Wax s...

  16. In situ SIMS U-Pb dating of hydrothermal rutile: reliable age for the Zhesang Carlin-type gold deposit in the golden triangle region, SW China

    Science.gov (United States)

    Pi, Qiaohui; Hu, Ruizhong; Xiong, Bin; Li, Qiuli; Zhong, Richen

    2017-02-01

    The contiguous region between Guangxi, Guizhou, and Yunnan, commonly referred to as the Golden Triangle region in SW China, hosts many Carlin-type gold deposits. Previously, the ages of the gold mineralization in this region have not been well constrained due to the lack of suitable minerals for radiometric dating. This paper reports the first SIMS U-Pb age of hydrothermal rutile crystals for the Zhesang Carlin-type gold deposit in the region. The hydrothermal U-bearing rutile associated with gold-bearing sulfides in the deposit yields an U-Pb age of 213.6 ± 5.4 Ma, which is within the range of the previously reported arsenopyrite Re-Os isochron ages (204 ± 19 to 235 ± 33 Ma) for three other Carlin-type gold deposits in the region. Our new and more precise rutile U-Pb age confirms that the gold mineralization was contemporaneous with the Triassic W-Sn mineralization and associated granitic magmatism in the surrounding regions. Based on the temporal correlation, we postulate that coeval granitic plutons may be present at greater depths in the Golden Triangle region and that the formation of the Carlin-type gold deposits is probably linked to the coeval granitic magmatism in the region. This study clearly demonstrates that in situ rutile U-Pb dating is a robust tool for the geochronogical study of hydrothermal deposits that contain hydrothermal rutile.

  17. Hydrologic models of modern and fossil geothermal systems in the Great Basin: Genetic implications for epithermal Au-Ag and Carlin-type gold deposits

    Science.gov (United States)

    Person, M.; Banerjee, A.; Hofstra, A.; Sweetkind, D.; Gao, Y.

    2008-01-01

    The Great Basin region in the western United States contains active geothermal systems, large epithermal Au-Ag deposits, and world-class Carlin-type gold deposits. Temperature profiles, fluid inclusion studies, and isotopic evidence suggest that modern and fossil hydrothermal systems associated with gold mineralization share many common features, including the absence of a clear magmatic fluid source, discharge areas restricted to fault zones, and remarkably high temperatures (>200 ??C) at shallow depths (200-1500 m). While the plumbing of these systems varies, geochemical and isotopic data collected at the Dixie Valley and Beowawe geothermal systems suggest that fluid circulation along fault zones was relatively deep (>5 km) and comprised of relatively unexchanged Pleistocene meteoric water with small (enthalpy, ??18O, silica compositions of fluids and/or rocks, groundwater residence times, fluid inclusion homogenization temperatures, and apatite fission track anomalies. Our results suggest that these hydrothermal systems were driven by natural thermal convection along anisotropic, subvertical faults connected in many cases at depth by permeable aquifers within favorable lithostratigraphic horizons. Those with minimal fluid ?? 18O shifts are restricted to high-permeability fault zones and relatively small-scale (???5 km), single-pass flow systems (e.g., Beowawe). Those with intermediate to large isotopic shifts (e.g., epithermal and Carlin-type Au) had larger-scale (???15 km) loop convection cells with a greater component of flow through marine sedimentary rocks at lower water/rock ratios and greater endowments of gold. Enthalpy calculations constrain the duration of Carlin-type gold systems to probably concentrations suggest that the duration of the modern Beowawe system is enthalpy fluids. Computed fission track ages along the Carlin trend included the convective effects, and ranged between 91.6 and 35.3 Ma. Older fission track ages occurred in zones of

  18. Magnetic separation studies for a low grade siliceous iron ore sample

    Institute of Scientific and Technical Information of China (English)

    Dwari Ranjan Kumar; Rao Danda Srinivas; Reddy Palli Sita Ram

    2013-01-01

    Investigations were carried out,on a low grade siliceous iron ore sample by magnetic separation,to establish its amenability for physical beneficiation.Mineralogical studies revealed that the sample consists of magnetite,hematite and goethite as major opaque oxide minerals where as silicates as well as carbonates form the gangue minerals in the sample.Processes involving combination of classification,dry magnetic separation and wet magnetic separation were carried out to upgrade the low grade siliceous iron ore sample to make it suitable as a marketable product.The sample was first ground and each closed size sieve fractions were subjected to dry magnetic separation and it was observed that limited upgradation is possible.The ground sample was subjected to different finer sizes and separated by wet low intensity magnetic separator.It was possible to obtain a magnetic concentrate of 67% Fe by recovering 90% of iron values at below 200 μm size.

  19. Determination of specific activity of 230Th in uranium ore samples

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A new method suitable for determining specific activity of 230Th in uranium ore samples is built. The method is characterized by adding the 230Th/ 232Th standard dilution agent with lower activity ratio (Its 230Th/ 232Th activity ratio and 230Th have been known) to the samples and using isotopic dilution analysis. The method can be applied to analyses of 230Th specific activity in various 230Th/ 232Th activity ratio samples. The precision can also be improved.

  20. Removal of Pb ion from water samples using red mud (bauxite ore processing waste)

    OpenAIRE

    Ghorbani A.; Nazarfakhari M.; Pourasad Y.; Mesgari Abbasi S.

    2014-01-01

    This work presented the use of red mud (bauxite ore processing waste) in removal of lead ions in water samples. For this 0.1 g of red mud has been used as adsorbent which suspended in 10 ml of lead solution with the concentration of 50 mg l-1 for about 1 h. After that the lead concentration in the samples taken from the red mud treated lead solution measured with atomic absorption spectroscopy (AAS). The effect of some parameter which is important in adsorption of lead on red mud such as suit...

  1. Neutron capture gamma-ray spectroscopy and its analytical applications for gold ore sample using the reactor neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, A.M.; El-Kady, A.A.; Rofail, N.B.; Hamouda, I.

    1981-01-01

    Prompt gamma-rays which immediately follow thermal neutrons capture have been used as a technique for non-destructive elemental analysis for gold ore sample. The thermal column of the Egyptian Research Reactor - 1 (ET-RR-1) was used. This requires a design of a well collimated and thermalized neutron beam. A high resolution and high efficiency Ge (Li) detector was required. In order to estimate the content of gold in its ore, calibration curves were constructed. For testing the results obtained, an empirical formula including the thermal neutron flux, the microscopic cross-section and the absolute efficiency of the detection system were applied. The concentration of gold in its ore sample was found to be as low as 5 ppM. Several elements beside gold could be identified in the ore sample. 10 references.

  2. Microcomputer-based pneumatic controller for neutron activation analysis. [For analyzing uranium ore samples

    Energy Technology Data Exchange (ETDEWEB)

    Byrd, J.S.; Sand, R.J.

    1976-10-01

    A microcomputer-based pneumatic controller for neutron activation analysis was designed and built at the Savannah River Laboratory for analysis of large numbers of geologic samples for locating potential supplies of uranium ore for the National Uranium Resource Evaluation program. In this system, commercially available microcomputer logic modules are used to transport sample capsules through a network of pressurized air lines. The logic modules are interfaced to pneumatic valves, solenoids, and photo-optical detectors. The system operates from programs stored in firmware (permanent software). It also commands a minicomputer and a hard-wired pulse height analyzer for data collection and bookkeeping tasks. The advantage of the system is that major system changes can be implemented in the firmware with no hardware changes. This report describes the hardware, firmware, and software for the electronics system.

  3. Removal of Pb ion from water samples using red mud (bauxite ore processing waste

    Directory of Open Access Journals (Sweden)

    Ghorbani A.

    2014-07-01

    Full Text Available This work presented the use of red mud (bauxite ore processing waste in removal of lead ions in water samples. For this 0.1 g of red mud has been used as adsorbent which suspended in 10 ml of lead solution with the concentration of 50 mg l-1 for about 1 h. After that the lead concentration in the samples taken from the red mud treated lead solution measured with atomic absorption spectroscopy (AAS. The effect of some parameter which is important in adsorption of lead on red mud such as suitable adsorbent dosage, pH and contact time of solution and adsorbent was investigated. The result shows that red mud as solid waste and low-cost adsorbent can be successfully used for the removal of lead ion from aqueous solution.

  4. Elemental analysis of some Egyptian ores and industrial iron samples by neutron activation analysis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Elemental analysis of iron ore samples and first industrial iron production prepared by the Egyptian Iron and Steel Company of Helwan near Cairo were determined by instrumental neutron activation analysis technique. Five samples from each kind were irradiated for a 48 hours at a thermal neutron flux of 4x1012 n/(cm2.s) in the first Egyptian research reactor ET-PP-1. Also the pneumatic irradiation rabbit system (PIRS) attached to the reactor in Inshass, was used to measure the elements of short-life time.The gamma-ray spectra were recorded by means of the hyper pure germanium detection system. The concentration percentage values of major, minor and trace elements are presented. The long and short lived isotopes were considered. A comparative study and a discussion on the elemental concentration values are given.

  5. Elemental analysis of some Egyptian ores and industrial iron samples by neutron activation analysis.

    Science.gov (United States)

    Srror, A; Abdel-Basset, N; Abdel-Haleem, A S; Hassan, A M

    2001-01-01

    Elemental analysis of iron ore samples and first industrial iron production prepared by the Egyptian Iron and Steel Company of Helwan near Cairo were determined by instrumental neutron activation analysis technique. Five samples from each kind were irradiated for a 48 hours at a thermal neutron flux of 4 x 10(12) n/(cm2.s) in the first Egyptian research reactor ET-RR-1. Also the Pneumatic irradiation Rabbit system (PIRS) attached to the reactor in Inshass, was used to measure the elements of short-life time. The gamma-ray spectra were recorded by means of the hyper pure germanium detection system. The concentration percentage values of major, minor and trace elements are presented. The long and short lived isotopes were considered. A comparative study and a discussion on the elemental concentration values are given.

  6. Elemental analysis of two Egyptian iron ores and produced industrial iron samples by neutron activation analysis.

    Science.gov (United States)

    Sroo, A; Abdel-Basset, N; Abdel-Haleem, A S; Hassan, A M

    2001-03-01

    Elemental analysis of two iron ores and initial industrial iron production prepared by the Egyptian Iron and Steel Company of Helwan near Cairo were performed by the instrumental neutron activation analysis technique. Five samples of each type were irradiated for 48 h in a thermal neutron flux of 4 x 10(12) n/cm2 s in the first Egyptian research reactor ET-RR-1. Also, the Pneumatic Irradiation Rabbit System (PIRS), attached to the reactor ET-RR-1 in Inshass, was used to measure short-life elements. The gamma-ray spectra were obtained with a hyper pure germanium detection system. The concentration percentage values of major, minor and trace elements are presented. Implications of the elemental concentration values obtained are presented.

  7. Elemental analysis of two Egyptian iron ores and produced industrial iron samples by neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Sroor, A.; Abdel-Basset, N.; Abdel-Haleem, A.S.; Hassan, A.M

    2001-03-01

    Elemental analysis of two iron ores and initial industrial iron production prepared by the Egyptian Iron and Steel Company of Helwan near Cairo were performed by the instrumental neutron activation analysis technique. Five samples of each type were irradiated for 48 h in a thermal neutron flux of 4x10{sup 12} n/cm{sup 2} s in the first Egyptian research reactor ET-RR-1. Also, the Pneumatic Irradiation Rabbit System (PIRS), attached to the reactor ET-RR-1 in Inshass, was used to measure short-life elements. The {gamma}-ray spectra were obtained with a hyper pure germanium detection system. The concentration percentage values of major, minor and trace elements are presented. Implications of the elemental concentration values obtained are presented.

  8. Integration of new geologic mapping and satellite-derived quartz mapping yields insights into the structure of the Roberts Mountains allochthon applicable to assessments for concealed Carlin-type gold deposits

    Science.gov (United States)

    Holm-Denoma, Christopher S.; Hofstra, Albert H.; Rockwell, Barnaby W.; Noble, Paula J.

    2012-01-01

    Geologic mapping and remote sensing across north-central Nevada enable recognition of a thick sheet of Middle and Upper Ordovician Valmy Formation quartzite that structurally overlies folded and faulted Ordovician through Devonian stratigraphic units of the Roberts Mountains allochthon. In the northern Independence Mountains and nearby Double Mountain area, the Valmy Formation is in fault contact with Ordovician through Silurian, predominantly clastic, sedimentary rocks of the Roberts Mountains allochthon that were deformed prior to, or during, emplacement of the Valmy thrust sheet. Similar structural relations are recognized discontinuously for 200 kilometers along the strike of the Roberts Mountains allochthon in mapping guided by regional remote-sensing-based (ASTER) quartz maps. Overall thicknesses of deformed Roberts Mountains allochthon units between the base of the Valmy and the top of underlying carbonate rocks that host large Carlin-type gold deposits varies on the order of hundreds of meters but is not known to exceed 700 meters. The base of the Valmy thrust sheet is a complimentary datum in natural resource exploration and mineral resource assessment for concealed Carlin-type gold deposits.

  9. Analytical Results for 42 Fluvial Tailings Cores and 7 Stream Sediment Samples from High Ore Creek, Northern Jefferson County, Montana

    Science.gov (United States)

    Fey, David L.; Church, Stan E.

    1998-01-01

    Metal-mining related wastes in the Boulder River basin study area in northern Jefferson County, Montana have been implicated in their detrimental effects on water quality with regard to acid-generation and toxic-metal solubility. Sediments, fluvial tailings and water from High Ore Creek have been identified as significant contributors to water quality degradation of the Boulder River below Basin, Montana. A study of 42 fluvial tailings cores and 7 stream sediments from High Ore Creek was undertaken to determine the concentrations of environmentally sensitive elements (i.e. Ag, As, Cd, Cu, Pb, Zn) present in these materials, and the mineral phases containing those elements. Two sites of fluvial deposition of mine-waste contaminated sediment on upper High Ore Creek were sampled using a one-inch soil probe. Forty-two core samples were taken producing 247 subsamples. The samples were analyzed by ICP-AES (inductively coupled-plasma atomic emission spectroscopy) using a total mixed-acid digestion. Results of the core analyses show that the elements described above are present at very high concentrations (to 22,000 ppm As, to 460 ppm Ag, to 900 ppm Cd, 4,300 ppm Cu, 46,000ppm Pb, and 50,000 ppm Zn). Seven stream-sediment samples were also analyzed by ICP-AES for total element content and for leachable element content. Results show that the sediment of High Ore Creek has elevated levels of ore-related metals throughout its length, down to the confluence with the Boulder River, and that the metals are, to a significant degree, contained in the leachable phase, namely the hydrous amorphous iron- and manganese-hydroxide coatings on detrital sediment particles.

  10. A Methodology to Estimate Ores Work Index Values, Using Miduk Copper Mine Sample

    Directory of Open Access Journals (Sweden)

    Mohammad Noaparast

    2012-12-01

    Full Text Available It is always attempted to reduce the costs of comminution in mineral processing plants. One of thedifficulties in size reduction section is not to be designed properly. The key factor to design size reductionunits such as crushers and grinding mills, is ore’s work index. The work index, wi, presents the oregrindability, and is used in Bond formula to calculate the required energy. Bond has defined a specificrelationship between some parameters which is applied to calculate wi, which are control screen, fineparticles produced, feed and product d80.In this research work, a high grade copper sample from Miduk copper concentrator was prepared, and itswork index values were experimentally estimated, using different control screens, 600, 425, 212, 150, 106and 75 microns. The obtained results from the tests showed two different behaviors in fine production.According to these two trends the required models were then defined to present the fine mass calculationusing control screen. In next step, an equation was presented in order to calculate Miduk copper ore workindex for any size. In addition to verify the model creditability, a test using 300 microns control screenwas performed and its result was compared with calculated ones using defined model, which showed agood fit. Finally the experimental and calculated values were compared and their relative error was equalto 4.11% which is an indication of good fit for the results.

  11. Nuclear forensic analysis of an unknown uranium ore concentrate sample seized in a criminal investigation in Australia.

    Science.gov (United States)

    Keegan, Elizabeth; Kristo, Michael J; Colella, Michael; Robel, Martin; Williams, Ross; Lindvall, Rachel; Eppich, Gary; Roberts, Sarah; Borg, Lars; Gaffney, Amy; Plaue, Jonathan; Wong, Henri; Davis, Joel; Loi, Elaine; Reinhard, Mark; Hutcheon, Ian

    2014-07-01

    Early in 2009, a state policing agency raided a clandestine drug laboratory in a suburb of a major city in Australia. During the search of the laboratory, a small glass jar labelled "Gamma Source" and containing a green powder was discovered. The powder was radioactive. This paper documents the detailed nuclear forensic analysis undertaken to characterise and identify the material and determine its provenance. Isotopic and impurity content, phase composition, microstructure and other characteristics were measured on the seized sample, and the results were compared with similar material obtained from the suspected source (ore and ore concentrate material). While an extensive range of parameters were measured, the key 'nuclear forensic signatures' used to identify the material were the U isotopic composition, Pb and Sr isotope ratios, and the rare earth element pattern. These measurements, in combination with statistical analysis of the elemental and isotopic content of the material against a database of uranium ore concentrates sourced from mines located worldwide, led to the conclusion that the seized material (a uranium ore concentrate of natural isotopic abundance) most likely originated from Mary Kathleen, a former Australian uranium mine.

  12. Assessment of natural radioactivity in phosphate ore, phosphogypsum and soil samples around a phosphate fertilizer plant in Nigeria.

    Science.gov (United States)

    Okeji, Mark C; Agwu, Kenneth K; Idigo, Felicitas U

    2012-11-01

    The radionuclides present in phosphate ore, phosphogypsum and soil samples in the vicinity of a phosphate fertilizer plants in Nigeria were identified and their activity concentration determined to assess the potential radiation impact on the environment due to fertilizer production. The mean activity concentration of (238)U, (232)Th, and (40)K radionuclides in phosphate ore samples were 616 ± 38.6, BDL (Below Detection Level) and 323.7 ± 57.5 Bq kg(-1) respectively. For the phosphogypsum, 334.8 ± 8.8, 4.0 ± 1.4, and 199.9 ± 9.3 Bq kg(-1) respectively and for soil samples range from 20.5 ± 7.3 to 175.7 ± 10.5 Bq kg(-1) for (226)Ra, 15.5 ± 1.5 to 50.4 ± 0.6 Bq kg(-1) for (232)Th and 89.5 ± 8.1 to 316.1 ± 41.3 Bq kg(-1) for (40)K respectively. The mean absorbed dose rate was 71.4 nGy h(-1). The mean annual effective dose was 86 μSv.

  13. Evidence for large-magnitude, post-Eocene extension in the northern Shoshone Range, Nevada, and its implications for Carlin-type gold deposits in the lower plate of the Roberts Mountains allochthon

    Science.gov (United States)

    Colgan, Joseph P.; Henry, Christopher D.; John, David A.

    2014-01-01

    The northern Shoshone and Toiyabe Ranges in north-central Nevada expose numerous areas of mineralized Paleozoic rock, including major Carlin-type gold deposits at Pipeline and Cortez. Paleozoic rocks in these areas were previously interpreted to have undergone negligible postmineralization extension and tilting, but here we present new data that suggest major post-Eocene extension along west-dipping normal faults. Tertiary rocks in the northern Shoshone Range crop out in two W-NW–trending belts that locally overlie and intrude highly deformed Lower Paleozoic rocks of the Roberts Mountains allochthon. Tertiary exposures in the more extensive, northern belt were interpreted as subvertical breccia pipes (intrusions), but new field data indicate that these “pipes” consist of a 35.8 Ma densely welded dacitic ash flow tuff (informally named the tuff of Mount Lewis) interbedded with sandstones and coarse volcaniclastic deposits. Both tuff and sedimentary rocks strike N-S and dip 30° to 70° E; the steeply dipping compaction foliation in the tuffs was interpreted as subvertical flow foliation in breccia pipes. The southern belt along Mill Creek, previously mapped as undivided welded tuff, includes the tuff of Cove mine (34.4 Ma) and unit B of the Bates Mountain Tuff (30.6 Ma). These tuffs dip 30° to 50° east, suggesting that their west-dipping contacts with underlying Paleozoic rocks (previously mapped as depositional) are normal faults. Tertiary rocks in both belts were deposited on Paleozoic basement and none appear to be breccia pipes. We infer that their present east tilt is due to extension on west-dipping normal faults. Some of these faults may be the northern strands of middle Miocene (ca. 16 Ma) faults that cut and tilted the 34.0 Ma Caetano caldera ~40° east in the central Shoshone Range (

  14. Rapid high-performance sample digestion of base metal ores using high-intensity infrared radiation with determination by nitrogen-based microwave plasma optical spectrometry

    Directory of Open Access Journals (Sweden)

    Yong Wang

    2016-03-01

    Full Text Available Infrared sample digestion technology has been rapidly developed in recent years and its application and digestion performance on a variety of ores of base metals was assessed in this study, using a 6-channel infrared digester. Digestion times of 10 min or less were achieved for all base metal ores investigated, including oxides, sulfides, and silicates of Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Ti, W, and Zn. Performance criteria for all samples were excellent, reflected in z values of less than 2 in all cases. Various acid digestion methods were developed for the selected ore samples under high intensity infrared radiation and delivered virtually complete recoveries of all of the elements of interest. Chromite, the notoriously refractory chromium ore was digested within 10 min and gave 100% recovery of chromium. These digestions were accomplished without resorting to perchloric acid and, for most sample types, without hydrofluoric acid, significantly improving the workplace safety for analysts. Between-channel variation of the analyte recoveries from the 6-channel unit were generally below 2%, suggesting that the digestion methods developed with this platform provide reproducible results to meet various sample preparation demands. The high speed and analyte recovery of these digestions makes this methodology especially attractive for prospectors and developers who demand rapid and reliable results from exploration samples.

  15. The coupled geochemistry of Au and As in pyrite from hydrothermal ore deposits

    Science.gov (United States)

    Deditius, Artur P.; Reich, Martin; Kesler, Stephen E.; Utsunomiya, Satoshi; Chryssoulis, Stephen L.; Walshe, John; Ewing, Rodney C.

    2014-09-01

    The ubiquity of Au-bearing arsenian pyrite in hydrothermal ore deposits suggests that the coupled geochemical behaviour of Au and As in this sulfide occurs under a wide range of physico-chemical conditions. Despite significant advances in the last 20 years, fundamental factors controlling Au and As ratios in pyrite from ore deposits remain poorly known. Here we explore these constraints using new and previously published EMPA, LA-ICP-MS, SIMS, and μ-PIXE analyses of As and Au in pyrite from Carlin-type Au, epithermal Au, porphyry Cu, Cu-Au, and orogenic Au deposits, volcanogenic massive sulfide (VHMS), Witwatersrand Au, iron oxide copper gold (IOCG), and coal deposits. Pyrite included in the data compilation formed under temperatures from ∼30 to ∼600 °C and in a wide variety of geological environments. The pyrite Au-As data form a wedge-shaped zone in compositional space, and the fact that most data points plot below the solid solubility limit defined by Reich et al. (2005) indicate that Au1+ is the dominant form of Au in arsenian pyrite and that Au-bearing ore fluids that deposit this sulfide are mostly undersaturated with respect to native Au. The analytical data also show that the solid solubility limit of Au in arsenian pyrite defined by an Au/As ratio of 0.02 is independent of the geochemical environment of pyrite formation and rather depends on the crystal-chemical properties of pyrite and post-depositional alteration. Compilation of Au-As concentrations and formation temperatures for pyrite indicates that Au and As solubility in pyrite is retrograde; Au and As contents decrease as a function of increasing temperature from ∼200 to ∼500 °C. Based on these results, two major Au-As trends for Au-bearing arsenian pyrite from ore deposits are defined. One trend is formed by pyrites from Carlin-type and orogenic Au deposits where compositions are largely controlled by fluid-rock interactions and/or can be highly perturbed by changes in temperature and

  16. Geological characteristics and ore-forming process of the gold deposits in the western Qinling region, China

    Science.gov (United States)

    Liu, Jiajun; Liu, Chonghao; Carranza, Emmanuel John M.; Li, Yujie; Mao, Zhihao; Wang, Jianping; Wang, Yinhong; Zhang, Jing; Zhai, Degao; Zhang, Huafeng; Shan, Liang; Zhu, Laimin; Lu, Rukui

    2015-05-01

    The western Qinling, belonging to the western part of the Qinling-Dabie-Sulu orogen between the North China Block and South China Block, is one of the most important gold regions in China. Isotopic dates suggest that the Mesozoic granitoids in the western Qinling region emplaced during the Middle-Late Triassic, and the deposits formed during the Late Triassic. Almost all gold deposits in the western Qinling region are classified as orogenic, Carlin-type, and Carlin-like gold deposits, and they are the products of Qinling Orogenesis caused by the final collision between the North China Block and the South China Block. The early subduction of the Mian-Lue oceanic crust and the latter collision between South Qinling Terrane and the South China Block along the Mian-Lue suture generated lithosphere-scale thermal anomalies to drive orogen-scale hydrothermal systems. The collision-related magmatism also provided heat source for regional ore-forming fluids in the Carlin-like gold deposits. Orogenic gold deposits such as Huachanggou, Liziyuan, and Baguamiao lie between the Shang-Dan and Mian-Lue sutures and are confined to WNW-trending brittle-ductile shear zones in Devonian and Carboniferous greenschist-facies metasedimentary rocks that were highly-deformed and regionally-metamorphosed. These deposits are typical orogenic gold deposits and formed within a Late Triassic age. The deposits show a close relationship between Au and Ag. Ores contain mainly microscopic gold, and minor electrum and visible gold, along with pyrite. The ore-forming fluids were main metamorphic fluids. Intensive tectonic movements caused by orogenesis created fluid-migrating channels for precipitation locations. Although some orogenic gold deposits occur adjacent to granitoids, mineralization is not synchronous with magmatism; that is, the granitoids have no genetic relations to orogenic gold deposits. As ore-forming fluids converged into dilated fractures during the extension stage of orogenesis

  17. CARACTERIZAÇÃO TECNOLÓGICA EM AMOSTRAS MINERALIZADAS A ESTANHO DO ESTADO DE RONDÔNIA/TECHNOLOGICAL CHARACTERIZATION OF TIN ORE SAMPLES FROM RONDÔNIA STATE, BRAZIL

    National Research Council Canada - National Science Library

    A B Braz; H Kahn; R Contessotto; C Ulsen; M M M L Tassinari

    2014-01-01

    .... This article shows the results of mineralogical and technological characterization carried out in two samples of tin ores from RondOnia state, Brazil, aiming the to quantify the cassiterite and other...

  18. Kellad orelis

    Index Scriptorium Estoniae

    2000-01-01

    18. VI Tallinna toomkirikus organist Ines Maidre (kaastegev Kristjan Mäeots) kontsert "Kellad orelis". Kontserdiga esitleb I. Maidre ka oma samanimelist CD-d (kujundaja Margus Haavamägi), mis on osaliselt sisse mängitud Tallinna toomkiriku Ladegasti-Saueri orelil. Tänavu tähistatakse toomkiriku Maarja kella ja Lunastaja kella 315. aastapäeva.

  19. Determination of uranium, iron, copper, and nickel from ore samples by MEKC using N,N'-ethylene bis(salicylaldimine) as complexing reagent.

    Science.gov (United States)

    Mirza, Muhammed Aslam; Khuhawar, Muhammad Yar; Arain, Rafee

    2008-02-01

    An analytical procedure has been developed for the separation of dioxouranium(VI), iron(III), copper(II), nickel(II), cobalt(II), cobalt(III), palladium(II), and thorium(IV) by MEKC using N,N'-ethylene bis(salicylaldimine) (H(2)SA(2)en) as a complexing reagent with total runtime ore samples indicating its presence within 103-1789 microg/g with RSD within 0.79-1.87%. Likewise copper, nickel, and iron in their combined matrix were also simultaneously determined with RSD 0.4-1.6% (n = 6).

  20. MEKC determination of vanadium from mineral ore and crude petroleum oil samples using precapillary chelation with bis(salicylaldehyde)tetramethyl-ethylenediimine.

    Science.gov (United States)

    Mirza, Muhammad Aslam; Kandhro, Abdul Jabbar; Khuhawar, Muhammad Yar; Arain, Rafee

    2009-09-01

    An analytical procedure has been developed for the separation of Cu(II), Ni(II), Co(II), Fe(II), Pd(II), Th(IV), V(IV), and determination of Fe(II), Co(II), Ni(II), and V(IV) by MEKC after chelation with bis(salicylaldehyde)tetramethylethylenediimine (H(2)SA(2)Ten). Uncoated fused silica capillary was used with an applied voltage of 30 kV with photo-diode array detection at 228 nm. SDS was added as micellar medium at pH 8.2 with sodium tetraborate buffer (0.1 M). Linear calibrations were established within 0.015-1000 microg/mL of each element with LOD within 5-67 ng/mL. The method was applied for the determination of vanadium from crude oil and ore samples in the range 0.34-2.40 and 114.2-720.7 microg/g with RSD 1.7-3.8 and 0.98-2.30% (n = 3), respectively. Fe, Ni, and Co present in crude oil and ore samples were also determined with RSD 1.3-2.8, 1.1-4.1, and 1.2-3.5% (n = 3), respectively. The results were compared with that of supplier's specifications and atomic absorption spectrometry (AAS). Method was evaluated by standard addition technique.

  1. Simultaneous determination of rare earth elements in ore and anti-corrosion coating samples using a portable capillary electrophoresis instrument with contactless conductivity detection.

    Science.gov (United States)

    Nguyen, Thi Anh Huong; Nguyen, Van Ri; Le, Duc Dung; Nguyen, Thi Thanh Binh; Cao, Van Hoang; Nguyen, Thi Kim Dung; Sáiz, Jorge; Hauser, Peter C; Mai, Thanh Duc

    2016-07-29

    The employment of an in-house-made capillary electrophoresis (CE) instrument with capacitively coupled contactless conductivity detection (C(4)D) as a simple and inexpensive solution for simultaneous determination of many rare earth elements (REEs) in ore samples from Vietnam, as well as in anti-corrosion coating samples is reported. 14 REEs (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) were determined using an electrolyte composed of 20mM arginine and 10mM α-hydroxyisobutyric acid adjusted to pH 4.2 with acetic acid. The best detection limit achieved was 0.24mg/L using the developed CE-C(4)D method. Good agreement between results from CE-C(4)D and the confirmation method (ICP-MS) was achieved, with a coefficient of determination (r(2)) for the two pairs of data of 0.998.

  2. 原子吸收光谱法测定矿样中金%Measurement of gold in sample ore by atomic absorption spectroscopy

    Institute of Scientific and Technical Information of China (English)

    陈隆荣

    2013-01-01

    After the sample is ignited in 650℃ and cold digested in aqua regia (1+1),gold is enriched by foamed plastics and is released by thiourea solution.The gold in the sample ore is measured by flame atomic absorption spectroscopy.This method is suit for measurement of gold in rock minerals which contains more than 0.05×10-6 gold.%试样经650℃灼烧,王水(1+1)冷浸泡分解试样,利用泡沫塑料富集金,采用硫脲溶液解脱金,用火焰原子吸收光谱法测定矿样中的金,本法适用岩石矿物中0.05×10-9以上金的测定。

  3. Uranium mill ore dust characterization

    Energy Technology Data Exchange (ETDEWEB)

    Knuth, R.H.; George, A.C.

    1980-11-01

    Cascade impactor and general air ore dust measurements were taken in a uranium processing mill in order to characterize the airborne activity, the degree of equilibrium, the particle size distribution and the respirable fraction for the /sup 238/U chain nuclides. The sampling locations were selected to limit the possibility of cross contamination by airborne dusts originating in different process areas of the mill. The reliability of the modified impactor and measurement techniques was ascertained by duplicate sampling. The results reveal no significant deviation from secular equilibrium in both airborne and bulk ore samples for the /sup 234/U and /sup 230/Th nuclides. In total airborne dust measurements, the /sup 226/Ra and /sup 210/Pb nuclides were found to be depleted by 20 and 25%, respectively. Bulk ore samples showed depletions of 10% for the /sup 226/Ra and /sup 210/Pb nuclides. Impactor samples show disequilibrium of /sup 226/Ra as high as +-50% for different size fractions. In these samples the /sup 226/Ra ratio was generally found to increase as particle size decreased. Activity median aerodynamic diameters of the airborne dusts ranged from 5 to 30 ..mu..m with a median diameter of 11 ..mu..m. The maximum respirable fraction for the ore dusts, based on the proposed International Commission on Radiological Protection's (ICRP) definition of pulmonary deposition, was < 15% of the total airborne concentration. Ore dust parameters calculated for impactor duplicate samples were found to be in excellent agreement.

  4. Application of the angle measure technique as image texture analysis method for the identification of uranium ore concentrate samples: New perspective in nuclear forensics.

    Science.gov (United States)

    Fongaro, Lorenzo; Ho, Doris Mer Lin; Kvaal, Knut; Mayer, Klaus; Rondinella, Vincenzo V

    2016-05-15

    The identification of interdicted nuclear or radioactive materials requires the application of dedicated techniques. In this work, a new approach for characterizing powder of uranium ore concentrates (UOCs) is presented. It is based on image texture analysis and multivariate data modelling. 26 different UOCs samples were evaluated applying the Angle Measure Technique (AMT) algorithm to extract textural features on samples images acquired at 250× and 1000× magnification by Scanning Electron Microscope (SEM). At both magnifications, this method proved effective to classify the different types of UOC powder based on the surface characteristics that depend on particle size, homogeneity, and graininess and are related to the composition and processes used in the production facilities. Using the outcome data from the application of the AMT algorithm, the total explained variance was higher than 90% with Principal Component Analysis (PCA), while partial least square discriminant analysis (PLS-DA) applied only on the 14 black colour UOCs powder samples, allowed their classification only on the basis of their surface texture features (sensitivity>0.6; specificity>0.6). This preliminary study shows that this method was able to distinguish samples with similar composition, but obtained from different facilities. The mean angle spectral data obtained by the image texture analysis using the AMT algorithm can be considered as a specific fingerprint or signature of UOCs and could be used for nuclear forensic investigation.

  5. THE TECHNIQUES OF THE STATIC CALIBRATION IN AUDIO MAGNETOTELLURIC AND ITS APPLICATION TO A CARLIN-TYPE GOLD DEPOSIT IN THE WEST OF GUIZHOU PROVINCE%静态校正技术在册亨县纳相金矿音频大地电磁法勘探中的应用

    Institute of Scientific and Technical Information of China (English)

    彭乾云; 周明平; 张德全; 杨炳南

    2012-01-01

    Audio magnetotelluric referred to AMT, as an magnetotelluric method , it is applied to the shallow-depth geophysical exploration. The probing depth is generally within 2000m. And it is an effective means of geophysical exploration. But the static effects is a difficult issue of the magnetotelluric method, it cause more trouble for data processing. This paper describes the basic principles of magnetotelluric method and the mechanism of Static Effects. And we discuss the different techniques in the static calibration. The paper takes a geophysical exploration of a carlin-type gold deposit in the west of Guizhou province for instance to introduce the Static Calibration s use in the data processing of AMT.%音频大地电磁测深,简称AMT(Audio Magnetotelluric),作为大地电磁勘探方法的一种,适用于中浅层地球物理勘查,探测深度一般在2 000m之内,是一种有效的地球物理勘探方法.但静态效应是电磁方法中较为棘手的一个问题,为数据资料的处理带来了极大地不便.这里简要阐述大地电磁方法基本原理和静态效应产生的机理,并对不同的静态校正技术进行论述.同时还介绍了该技术在黔西南卡林型金矿的具体应用及应用效果,结果表明,该技术较好地克服了静态效应所带来的影响.

  6. Endogenic Au-Ag polymetallic ore deposits and ore-bearing potentiality of strata

    Institute of Scientific and Technical Information of China (English)

    WANG Baode; NIU Shuyin; SUN Aiqun; XIE Yan; LUO Yi; LIU Hailong; WANG Yanhua

    2010-01-01

    The problem of ore-bearing potentiality of the strata involves metallogenic theory and ore-search orientation. Studies of the spatial distribution of endogenic Au-Ag polymetallic ore deposits in North Hebei indicated that the strata in which ore deposits occurred range in age from Paleozoic, Proterozoic to Mesozoic. In addition the ore deposits are characterized as being strata-bound in nature. The arise and establishment of "extracting" viewpoint may be attributed to the following three reasons: 1) influence by the idea of "ore-source bed"; 2) limitation of analytical techniques in the 1980s' (especially gold element); and 3) a small number of samples (sampling locations were mostly disturbed by mineralization). Studies have shown that ore-forming materials would most probably come from the deep interior of the Earth. Deep-seated ore-bearing materials including Au-Ag polymetals were brought to the shallow levels by way of mantle plume-mantle sub-plume-mantle branch structure multi-stage evolution, finally leading to the formation of ore deposits.

  7. 几种分解方法在光度法测定含钼矿样中钼的比较%Comparison of Several Decomposition Methods for Determination of Molybdenum in Ore Sample by Spectrophotometric Method

    Institute of Scientific and Technical Information of China (English)

    万仲建; 牛春林; 王前会; 李运红; 李玉仙

    2013-01-01

    考察了碱熔解法、酸溶解法和烧结法分解含钼矿样品的条件,结合硫氰酸钾分光光度法比较了铝的分析结果.结果表明:碱熔解法适用于钼含量≥0.1%,铜、铁、钙、镁和氟等较高含量的样品的熔解;酸溶解法适用于钼含量<0.1%,易溶且干扰元素较少的样品的溶解;烧结法适用于钼含量<0.1%的含硅、铅等较高含量样品的分解.方法应用于钨矿石标准样品,地质矿、原矿、尾矿和铜精矿样品的分解及其钼的测定中结果满意.%The conditions of molybdenum containing ore sample's decomposition methods of alkali fusion, acid dissolution and sintering are investigated, the analysis results of different decomposition method by potassium thiocyanate spectrophotometry are compared. The results show that; alkali fusion method is suitable for the sample that the molybdenum content is 50. 1% , and copper, iron, calcium, magnesium and fluorin content is higher; acid solution method is suitable for the sample which is ease of solubility and has less interference element, and the molybdenum content is < 0. 1 % ; sintering method is suitable for the sample of molybdenum content < 0. 1 % , with higher content of silicon, lead and so on. The methods are suitable for the decomposition of the standard sample of tungsten ore, geology ore, raw ore, tailings and copper concentrate sample, as well as in the determination of molybdenum, and the results are satisfactory.

  8. Gold-bearing Characteristics of Arsenian Pyrites and Arsenopyrites in the Bojitian Carlin-type Gold Deposits, Southwestern Guizhou Province, Southwest China%黔西南簸箕田卡林型金矿中含砷黄铁矿和毒砂的赋金特征研究

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

      黔西南簸箕田金矿是新近发现的一个中型卡林型金矿。该文在显微镜矿相学观察的基础上,采用电子探针显微分析,包括背散射电子图像、点分析和面分析,对金矿中的赋金矿物展开了基本特征和赋金状态研究,发现含砷黄铁矿和毒砂是主要的赋金矿物。赋金黄铁矿又以环带状和细粒自形为主,莓球状、粗粒以及条带状次之。这些黄铁矿成因复杂,并且可能普遍受到热液蚀变作用影响。环带状黄铁矿核部中的金可能主要以“不可见”超显微包裹金(纳米级自然金,Au0)的形式赋存,而环带部分中的金可能以固溶体金(Au+)的形式赋存,并也可能存在纳米级自然金(Au0)。相比而言,莓球状、粗粒和条带状黄铁矿中的金既可能含有纳米级自然金(Au0),也可能含有固溶体金(Au+)。对于毒砂,单独的毒砂和黄铁矿-毒砂集合体中的毒砂均为热液成因,都赋存金,但以单独的毒砂为主,金以“不可见”超显微包裹金(纳米级自然金, Au0)的形式存在。%The recently discovered Bojitian carlin-type gold deposits are located in the southwestern Guizhou Province and are middle in scale. In this study, we investigated the mineral’s gold-bearing characteristics based on integrated studies of microscope observations and electron-probe back-scattered image, element spot and element map analyses. Analytical results show that arsenian pyrites and arsenopyrites are major gold-bearing minerals. The gold-bearing pyrites are dominated by zoned arsenian pyrites and fine-grained arsenian pyrites, followed by framboidal pyrites, coarse-grained pyrites, and banded pyrites. These pyrites have complex origins and most of them may hare undergone hydrothermal alterations. The gold in the cores of the zoned arsenian pyrites occurs as“invisible”microscopic inclusions of gold grains (nanoparticles of native gold

  9. Radon emanation from low-grade uranium ore.

    Science.gov (United States)

    Sahu, Patitapaban; Mishra, Devi Prasad; Panigrahi, Durga Charan; Jha, Vivekanand; Patnaik, R Lokeswara

    2013-12-01

    Estimation of radon emanation in uranium mines is given top priority to minimize the risk of inhalation exposure due to short-lived radon progeny. This paper describes the radon emanation studies conducted in the laboratory as well as inside an operating underground uranium mine at Jaduguda, India. Some of the important parameters, such as grade/(226)Ra activity, moisture content, bulk density, porosity and emanation fraction of ore, governing the migration of radon through the ore were determined. Emanation from the ore samples in terms of emanation rate and emanation fraction was measured in the laboratory under airtight condition in glass jar. The in situ radon emanation rate inside the mine was measured from drill holes made in the ore body. The in situ(222)Rn emanation rate from the mine walls varied in the range of 0.22-51.84 × 10(-3) Bq m(-2) s(-1) with the geometric mean of 8.68 × 10(-3) Bq m(-2) s(-1). A significant positive linear correlation (r = 0.99, p 222)Rn emanation rate and the ore grade was observed. The emanation fraction of the ore samples, which varied in the range of 0.004-0.089 with mean value of 0.025 ± 0.02, showed poor correlation with ore grade and porosity. Empirical relationships between radon emanation rate and the ore grade/(226)Ra were also established for quick prediction of radon emanation rate from the ore body.

  10. Aluminum substitution in goethite in lake ore

    Directory of Open Access Journals (Sweden)

    Carlson, L.

    1995-06-01

    Full Text Available The extent of substitution of Fe by Al in goethite in 32 lake ore samples collected from 11 lakes in Finland varied between 0 and 23 mol-%. The data indicated a negative relationship between Al-substitution and the particle size of lake ore. Differences in the Al-substitution were apparent between sampling sites, suggesting that kinetic and environmental variation in lake ore formation influences the substitution. Non-substituted goethite is formed in coarse-grained sediments with locally high concentrations of Fe due to iron-rich springs. Unit cell edge lengths and volumes of goethite varied as function of Al-subsitution but deviated from the Vegard relationship towards higher values.

  11. Processing of lateritic ores

    Energy Technology Data Exchange (ETDEWEB)

    Collier, D.E.; Ring, R.J. [Environment Division, Australian Nuclear Science and Technology Organisation, Menai, New South Wales (Australia); McGill, J.; Russell, H. [Energy Resources of Australia Ltd., Ranger Mine, Jabiru, Northern Territory (Australia)

    2000-07-01

    Highly weathered or lateritic ores that contain high proportions of fine clay minerals present specific problems when they are processed to extract uranium. Of perhaps the greatest significance is the potential of the fine minerals to adsorb dissolved uranium (preg-robbing) from leach liquors produced by processing laterites or blends of laterite and primary ores. These losses can amount to 25% of the readily soluble uranium. The clay components can also restrict practical slurry densities to relatively low values in order to avoid rheology problems in pumping and agitation. The fine fractions also contribute to relatively poor solid-liquid separation characteristics in settling and/or filtration. Studies at ANSTO have characterised the minerals believed to be responsible for these problems and quantified the effects of the fines in these types of ores. Processing strategies were also examined, including roasting, resin-in-leach and separate leaching of the laterite fines to overcome potential problems. The incorporation of the preferred treatment option into an existing mill circuit is discussed. (author)

  12. Complexing and hydrothermal ore deposition

    CERN Document Server

    Helgeson, Harold C

    1964-01-01

    Complexing and Hydrothermal Ore Deposition provides a synthesis of fact, theory, and interpretative speculation on hydrothermal ore-forming solutions. This book summarizes information and theory of the internal chemistry of aqueous electrolyte solutions accumulated in previous years. The scope of the discussion is limited to those aspects of particular interest to the geologist working on the problem of hydrothermal ore genesis. Wherever feasible, fundamental principles are reviewed. Portions of this text are devoted to calculations of specific hydrothermal equilibriums in multicompone

  13. Vertical mill simulation applied to iron ores

    Directory of Open Access Journals (Sweden)

    Douglas Batista Mazzinghy

    2015-04-01

    Full Text Available The application of vertical mills in regrind circuits is consolidated. This type of mill is now attracting interest in primary grinding applications, due to its higher efficiency when compared to ball mills, which are usually used at this stage. In this study, a coarse sample of iron ore was tested in a pilot scale grinding circuit with a vertical mill. Other three samples of pellet feed had already been tested with the methodology used in this study. The sample of coarse iron ore was characterized in laboratory tests carried out in a small batch ball mill. Selection and breakage function parameters were determined from the laboratory tests. The parameters were then used for simulating the pilot scale tests using Modsim™ software. The model previously implemented in Modsim™ has been successfully applied to represent the vertical mill operated with different ores. The simulations produced particle size distributions that were very close to the actual size distributions, and the predictions were accomplished only by imputing the calibrated parameters from the batch tests, the power draw and the feed size distribution of the pilot tests. The methodology is therefore useful for scale-up and simulation of vertical mills, only requiring laboratory tests that can be carried out in standard laboratory batch ball mills with small amounts of samples.

  14. The Revovery of Copper and Cobalt from Oxidized Copper Ore and Converter Slag

    OpenAIRE

    ZİYADANOĞULLARI, Berrin; ZİYADANOĞULLARI, Recep

    1999-01-01

    The aim of this study was to develop a method for obtaining copper and cobalt from oxidized copper ore and converter slag. In order to convert the copper and cobalt into sulfate compounds the main step was to roast the samples obtained by sulfurization and transfer the samples into solution. First the oxidized copper ore was roasted, followed by the mixture of converter slag and oxidized copper ore. Since the levels of copper and cobalt were low, the sulfurization process was carri...

  15. Hunting for Iron Ore Bargains

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    One of China’s leading steel mills has turned to smaller mines for long-term, lowcost iron ore supplies china’s oldest steel producer is looking to South America to fulfill its iron ore needs in the face of rising prices from

  16. ITABIRITE IRON ORE CONCENTRATION BY PNEUMATIC FLOTATION CELL

    Directory of Open Access Journals (Sweden)

    Angelo Quintiliano Nunes da Silva

    2015-06-01

    Full Text Available The main iron ore processing plants in Brazil operate through reverse cationic flotation. Many studies have been conducted in order to improve flotation efficiency by optimization process variables. The pneumatic flotation cell stands out due to the simplicity to and to the intense contact particle/bubble promoted by the pulp feeding system. In this study, laboratory scale and pilot were conducted using a sample of itabirite iron ore. The objectives are evaluating the performance of this device using low grade iron ore, and drawing a comparison with laboratory scale tests on conventional flotation cell. The results indicate the potential application of pneumatic flotation cell to the ore tested. Adjustments in the feed particle size and process optimizations can be performed on the concentrate, reaching Fe and SiO2 grades used by the industry

  17. Radioanalysis of RE enrichment of ion adsorption type RE ores

    CERN Document Server

    Zhao Shu Quan; Hu He Ping; Li Fu Sheng; Chen Ying Min; LiuShiMing

    2002-01-01

    Objective: To analyze the radioactivity in Rare Earth (RE) enrichment of ion adsorption type RE ores. Methods: Using HPGe-gamma spectrometer to analyze the activity ratio of gamma radionuclides in kind of samples, using FJ-2603 low background alpha, beta measurement apparatus to measure their total alpha and total beta activities, and using X-ray fluorescence spectrometer to analyze contents of La sub 2 O sub 3 and Y sub 2 O sub 3 , respectively. Results: HPGe gamma spectroscopy and X-ray fluorescence spectroscopy are simple, convenient and non-destructive methods of analyzing radionuclides and La sub 2 O sub 3 , Y sub 2 O sub 3 in RE enrichment of ion adsorption type RE ores, respectively. Conclusion: The basic data were provided for radiation protection and treatment of gas, liquid and solid waste in RE production of ion adsorption type RE ores; method and experience were provided for studying ion adsorption type RE ores

  18. A comparison of portable XRF and ICP-OES analysis for lead on air filter samples from a lead ore concentrator mill and a lead-acid battery recycler.

    Science.gov (United States)

    Harper, Martin; Pacolay, Bruce; Hintz, Patrick; Andrew, Michael E

    2006-03-01

    Personal and area samples for airborne lead were taken at a lead mine concentrator mill, and at a lead-acid battery recycler. Lead is mined as its sulfidic ore, galena, which is often associated with zinc and silver. The ore typically is concentrated, and partially separated, on site by crushing and differential froth flotation of the ore minerals before being sent to a primary smelter. Besides lead, zinc and iron are also present in the airborne dusts, together with insignificant levels of copper and silver, and, in one area, manganese. The disposal of used lead-acid batteries presents environmental issues, and is also a waste of recoverable materials. Recycling operations allow for the recovery of lead, which can then be sold back to battery manufacturers to form a closed loop. At the recycling facility lead is the chief airborne metal, together with minor antimony and tin, but several other metals are generally present in much smaller quantities, including copper, chromium, manganese and cadmium. Samplers used in these studies included the closed-face 37 mm filter cassette (the current US standard method for lead sampling), the 37 mm GSP or "cone" sampler, the 25 mm Institute of Occupational Medicine (IOM) inhalable sampler, the 25 mm Button sampler, and the open-face 25 mm cassette. Mixed cellulose-ester filters were used in all samplers. The filters were analyzed after sampling for their content of the various metals, particularly lead, that could be analyzed by the specific portable X-ray fluorescence (XRF) analyzer under study, and then were extracted with acid and analyzed by inductively coupled plasma optical emission spectroscopy (ICP-OES). The 25 mm filters were analyzed using a single XRF reading, while three readings on different parts of the filter were taken from the 37 mm filters. For lead at the mine concentrate mill, all five samplers gave good correlations (r2 > 0.96) between the two analytical methods over the entire range of found lead mass

  19. Microbial reduction of iron ore

    Science.gov (United States)

    Hoffmann, Michael R.; Arnold, Robert G.; Stephanopoulos, Gregory

    1989-01-01

    A process is provided for reducing iron ore by treatment with microorganisms which comprises forming an aqueous mixture of iron ore, microorganisms operable for reducing the ferric iron of the iron ore to ferrous iron, and a substrate operable as an energy source for the microbial reduction; and maintaining the aqueous mixture for a period of time and under conditions operable to effect the reduction of the ore. Preferably the microorganism is Pseudomonas sp. 200 and the reduction conducted anaerobically with a domestic wastewater as the substrate. An aqueous solution containing soluble ferrous iron can be separated from the reacted mixture, treated with a base to precipitate ferrous hydroxide which can then be recovered as a concentrated slurry.

  20. A geochemical assessment of possible lunar ore formation

    Science.gov (United States)

    Haskin, Larry A.; Colson, Russell O.; Vaniman, David

    The Moon apparently formed without appreciable water or other relatively volatile materials. Interior concentrations of water or other volatile substances appear to be extremely low. On Earth, water is important to the genesis of nearly all types of ores. Thus, some have reasoned that only abundant elements would occur in ore concentrations. The definition and recognition of ores on the Moon challenge the imaginations and the terrestrial perceptions of ore bodies. Lunar ores included solar-wind soaked soils, which contain abundant but dilute H, C, N, and noble gases (including He-3). Oxygen must be mined; soils contain approximately 45 percent (wt). Mainstream processes of rock formation concentrated Si, Mg, Al, Fe, and Ca, and possibly Ti and Cr. The highland surface contains approximately 70 percent (wt) feldspar (mainly CaAl2Si2O8), which can be separated from some highland soils. Small fragments of dunite were collected; dunite may occur in walls and central peaks of some craters. Theoretical extensions of observations of lunar samples suggest that the Moon may have produced ores of trace elements. Some small fragments have trace-element concentrations 104 times higher than the lunar average, indicating that effective geochemical separations occurred; processes included fractional crystallization, silicate immiscibility, vaporization and condensation, and sulfide metamorphism. Operations of these processes acting on indigenous materials and on meteoritic material in the regolith could have produced ores. Infalling carbonaceous meteorites and comets have added water and hydrocarbons that may have been cold-trapped. Vesicles in basalts, pyroclastic beads, and reported transient events suggest gag emission from the lunar interior; such gas might concentrate and transport rare elements. Large impacts may disperse ores or produce them through deposition of heat at depth and by vaporization and subsequent condensation. The main problem in assessing lunar resources is

  1. On the use of bastnasite ore as a phosphor material

    Energy Technology Data Exchange (ETDEWEB)

    Mohapatra, M., E-mail: manojm@barc.gov.in; Natarajan, V.; Rajeswari, B.; Dhobale, A.R.; Godbole, S.V.

    2014-01-15

    Bastnasite ore obtained from Indian Rare Earth (IRE) was investigated for its possible use as a phosphor material. The material was characterized by X-ray diffraction (XRD), energy dispersive X-ray fluorescence (EDXRF), photoacoustic spectroscopy (PAS), photoluminescence (PL) and electron paramagnetic resonance spectroscopy (EPR) techniques. XRD studies revealed the semi processed ore to be consisting of single phase CeO{sub 2} with no other impurities. EDXRF studies revealed the presence of ‘Th’ and traces of ‘Sm’ along with ‘Ce’ in the sample. PAS studies revealed the presence of strong charge transfer from oxygen to cerium in the system. PL studies confirmed the presence of at least four trivalent rare earths, viz. Sm, Eu, Dy and Tb in the system in trace quantities. The emission spectrum and decay time data were evaluated. It was observed that the rare earth ions are situated at distorted sites in the system surrounded by defect centers. EPR studies confirmed the presence of Ce{sup 3+}in the system along with electron trapped in oxygen ion vacancies. CIE indices for the ore sample were evaluated and it was seen that the overall emission from the system was in the ‘magenta’ region of the visible spectrum. The emission intensities were also compared with that of commercial samples. -- Highlights: • Characterization of bastnasite ore as a phosphor material. • Role of RE impurities in the luminescence • CIE index of the bastnasite ore.

  2. Isotopic tracing of ore-forming source materials for Dexing porphyry copper deposit of Jiangxi, China

    Institute of Scientific and Technical Information of China (English)

    Peng QIAN; Jianjun LU

    2008-01-01

    Dexing copper deposit is the biggest porphyry copper deposit in China. By researching isotopes of C,Si and Cu from the samples of Tongchang and Fujiawu ore-field, the authors found that δ13CPDB values of siderite were close to the δ13CPDB value of original magma; δ30Si values of the samples at the ore-forming stage were close to the δ30Si value range of magma, δ30Si values of partial samples were far away from it; Cu isotopic compositions of massive chalcopyrite formed at the early ore-forming stage are higher than that of veinal chalcopyrite formed at the later ore-forming stage. The results show that ore-forming materials were mainly derived from the porphyry body, and part of them were from wall rock materials.

  3. Ore petrography of low-grade siliceous manganese ores from the Bonai-Keonjhar belt, Orissa, India: The influence of mineral-fabric on their beneficiation

    Institute of Scientific and Technical Information of China (English)

    Mishra Subrat; Mohapatra Birendra Kumar; Dash Nilima; Rao Danda Srinivas

    2011-01-01

    Low grade siliceous manganese ores from the iron ore group of the Bonai-Keonjhar belt,Orissa,India are found mostly in shear zones.The ore characteristics of siliceous manganese ore samples from three different mines,viz.the Shankar (Barbil OMC lease hold area),the Sone-Patuli (Patmunda,OMM lease hold area),and the Musaghar (Roida,OMDC lease hold area),were studied.These siliceous manganese ores are of three types,respectively:(i) spongy-granular; (ii) massive-mosaic; and (iii) hard-mylonitized.The spongy-granular type contains granular,saccharoidal quartz and the major manganese mineral present is pyrolusite.The second type contains well crystallized quartz and cryptomelane,while the third has cherty,fine grained quartz (mylonite) along with romanechite.All three ores were subjected to physical beneflciation under similar conditions.Both gravity and magnetic separation techniques were employed.The mineral-fabric of the ores has been correlated to the extent of their beneflciation using these physical techniques.Of these three ores only the spongy-granular type responded well to upgrading.The feed with 22% Mn content could be upgraded to 44% with a 28% yield and a 49% recovery.The good response to beneficiation of the spongygranular sample could be due to the large euhedral crystals of pyrolusite and the friable nature of the saccharoidal quartz.This study reveals the influence of mineral-fabric on beneficiation of low grade ore,siliceous Mn ore in particular.

  4. Lead isotope studies of the Guerrero composite terrane, west-central Mexico: implications for ore genesis

    Science.gov (United States)

    Potra, Adriana; Macfarlane, Andrew W.

    2014-01-01

    field defined by the Huetamo Sequence, suggesting that these ores may also contain metals from the sedimentary rocks. The Pb isotope ratios of ore samples from the Zimapan deposit (206Pb/204Pb = 18.771-18.848) are substantially higher than the whole-rock Pb isotope compositions of the basement rocks. The similarity of ore Pb to igneous rock Pb in the Zimapan district (206Pb/204Pb = 18.800-18.968) may indicate that the proximal source of ore metals in the hydrothermal system was the igneous activity.

  5. Microbial Beneficiation of Salem Iron Ore Using Penicillium purpurogenum

    Science.gov (United States)

    Mishra, M.; Pradhan, M.; Sukla, L. B.; Mishra, B. K.

    2011-02-01

    High alumina and silica content in the iron ore affects coke rate, reducibility, and productivity in a blast furnace. Iron ore is being beneficiated all around the world to meet the quality requirement of iron and steel industries. Choosing a beneficiation treatment depends on the nature of the gangue present and its association with the ore structure. The advanced physicochemical methods used for the beneficiation of iron ore are generally unfriendly to the environment. Biobeneficiation is considered to be ecofriendly, promising, and revolutionary solutions to these problems. A characterization study of Salem iron ore indicates that the major iron-bearing minerals are hematite, magnetite, and goethite. Samples on average contains (pct) Fe2O3-84.40, Fe (total)-59.02, Al2O3-7.18, and SiO2-7.53. Penicillium purpurogenum (MTCC 7356) was used for the experiment . It removed 35.22 pct alumina and 39.41 pct silica in 30 days in a shake flask at 10 pct pulp density, 308 K (35 °C), and 150 rpm. In a bioreactor experiment at 2 kg scale using the same organism, it removed 23.33 pct alumina and 30.54 pct silica in 30 days at 300 rpm agitation and 2 to 3 l/min aeration. Alumina and silica dissolution follow the shrinking core model for both shake flask and bioreactor experiments.

  6. A Research of Ore-Forming Conditions of Nipu Gold Deposit in Guizhou Province, China%贵州泥堡金矿床成矿地质条件研究

    Institute of Scientific and Technical Information of China (English)

    孙军; 聂爱国; 黄思涵; 付斌; 陈世委

    2012-01-01

    The Nipu gold deposit is one of the important components of Carlin-type gold mining area, which is located in Southwest of Cuizhou Province. However, Nipu has its remarkable characteristics in host rocks, gold bearing formation and lithofacies palaeogeography. By researching the forming conditions of Nipu gold deposit, it is found that the mater and heat sources of Nibao gold deposit come from the Emei mantle plume's activities whichis the prerequisites of forming and activating the Ore-bearing hydrothermal. Also the location and formation of Nibao gold deposit are ultimately determined by a large scale of orogenic movements in Yanshanian period.%泥堡金矿是黔西南卡林型金矿矿集区的重要组成部分,但在赋矿岩石、含金建造和岩相古地理位置方面,泥堡金矿具有显著的特殊性.本文通过对贵州泥堡金矿床成矿地质条件的研究,分析认为峨眉山地幔热柱的活动为泥堡金矿的形成提供了物质来源和热能来源,为含矿热液的形成和活动创造了前提条件,燕山期大规模的构造造山运动最终决定了泥堡金矿的定位和形成.

  7. Investigation of chemical suppressants for inactivation of sulfide ores

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In order to investigate the effective control method of spontaneous combustion in the mining of sulfide ore deposits, This paper presents the testing results of several selected chemicals (water glass, calcium chloride, calcium oxide, magnesium oxide and their composites) as oxidation suppressants for sulfide ores. A weight increment scaling method was used to measure suppressant performance, and this method proved to be accurate, simple and convenient. Based on a large number of experiments, the test results show that four types of chemical mixtures demonstrate a good performance in reducing the oxidation rate of seven active sulfide ore samples by up to 27% to 100% during an initial 76 d period. The mixtures of water glass mixed with calcium chloride and magnesium oxide mixed with calcium chloride can also act as fire suppressants when used with fire sprinkling systems.

  8. Beneficiation of the gold bearing ore by gravity and flotation

    Science.gov (United States)

    Gül, Alim; Kangal, Olgaç; Sirkeci, Ayhan A.; Önal, Güven

    2012-02-01

    Gold concentration usually consists of gravity separation, flotation, cyanidation, or the combination of these processes. The choice among these processes depends on the mineralogical characterization and gold content of the ore. Recently, the recovery of gold using gravity methods has gained attention because of low cost and environmentally friendly operations. In this study, gold pre-concentrates were produced by the stepwise gravity separation and flotation techniques. The Knelson concentrator and conventional flotation were employed for the recovery of gold. Gold bearing ore samples were taken from Gümüşhane Region, northern east part of Turkey. As a result of stepwise Knelson concentration experiments, a gold concentrate assaying around 620 g/t is produced with 41.4wt% recovery. On the other hand, a gold concentrate about 82 g/t is obtained with 89.9wt% recovery from a gold ore assaying 6 g/t Au by direct flotation.

  9. Research on Magnesite Ore Purification

    Directory of Open Access Journals (Sweden)

    Berisha, K.

    2009-12-01

    Full Text Available Magnesite ore, consisting mainly of magnesite, MgCO3 is a chief mineral source for production of high quality refractory materials based on highly pure MgO. However, the presence of calcium and silicium mineral impurities in the ore adversely affect refractoriness. The removal of silicate minerals is now a routine process but it is not so for calcium minerals impurities. In this work, the new method for the removal of calcium mineral impurities from magnesite ore has been investigated. It is based on extraction of calcium hydroxide from the calcined hydrated ore with the solution of magnesium nitrate. The results show that it is possible to remove up to 65–83 % of calcium oxide (CaO within five minutes, and up to 88–95 % within an hour. The process itself is complex, but mainly under mass transfer control. It is possible to use waste materials produced as fertilizer in agriculture thus helping in environmental protection.

  10. Mineralogical Study of Zard Koh and Kulli Koh Iron Ore Deposits of Pakistan

    Directory of Open Access Journals (Sweden)

    SULTAN AHMED KHOSO

    2017-10-01

    Full Text Available Zard Koh and Kulli Koh are two recently discovered iron ore deposits, existing in the Chagai district, Balochistan, Pakistan. PSM (Pakistan Steel Mill Limited is interested to utilize these ore deposits at priority. Purpose of the present study was to assess the mineralogy of the Zard Koh and Kulli Koh iron ore deposits, as it plays a vital role in the selection of an appropriate processing method. The mineralogical study of ore deposits was carried out by XRD (X-Ray Diffraction, XRF (X-Ray Fluorescence, SEM (Scanning Electron Microscope attached with EDS (Energy Dispersive Spectroscope and SM (Stereomicroscope techniques. Results indicated that the Zard Koh ore is mainly composed of 60.15% maghemite, 23.57% pyrite, 4.07% chlorite, 10.30% grossular and 1.65% admontite minerals. The chemical analysis revealed that Zard Koh iron ore contains an average of 54.27% Fe, 12.73% S, 8.70% Si, 3.07% Al, 4.07% Ca, and 2.16% Mg. Similarly, the mineralogical study of the Kulli Koh iron ore indicated that, ore is containing 51.16% hematite, 29.24% quartz, 8.89% dravite, and 8.76% kaolinite minerals. Elemental analysis of different samples indicated that Kulli Koh iron ore contains an average composition of 40.23% Fe, 20.67% Si, 3.44% Ca, 3.81% Al and 3.25% Mg. Mineralogical study of the Zard Koh and Kulli Koh iron ore deposits suggested that these ore deposits can be beneficiated costeffectively by using magnetic separation techniques.

  11. Virtual phosphorus ore requirement of Japanese economy.

    Science.gov (United States)

    Matsubae, Kazuyo; Kajiyama, Jun; Hiraki, Takehito; Nagasaka, Tetsuya

    2011-08-01

    Phosphorus is indispensable for agricultural production. Hence, the consumption of imported food indirectly implies the import of phosphorus resources. The global consumption of agricultural products depends on a small number of ore-producing countries. For sustainable management of phosphorus resources, the global supply and demand network should be clarified. In this study, we propose the virtual phosphorus ore requirement as a new indicator of the direct and indirect phosphorus requirements for our society. The virtual phosphorus ore requirement indicates the direct and indirect demands for phosphorus ore transformed into agricultural products and fertilizer. In this study, the virtual phosphorus ore requirement was evaluated for the Japanese economy in 2005. Importantly, the results show that our society requires twice as much phosphorus ore as the domestic demand for fertilizer production. The phosphorus contained in "eaten" agricultural products was only 12% of virtual phosphorus ore requirement.

  12. Characterizing the economic value of an epithermal Au-Ag ore with Laser Induced Breakdown Spectroscopy (LIBS)

    NARCIS (Netherlands)

    Dalm, M.; Buxton, M.W.N.

    2016-01-01

    LIBS was applied to 19 Au-Ag ore samples to investigate if this technique can be used to distinguish between economic and sub-economic ore either by direct detection of these elements or by using other elements as indicators. However, the Au and Ag grades of the samples are below the detection limit

  13. Characterizing the economic value of an epithermal Au-Ag ore with Laser Induced Breakdown Spectroscopy (LIBS)

    NARCIS (Netherlands)

    Dalm, M.; Buxton, M.W.N.

    2016-01-01

    LIBS was applied to 19 Au-Ag ore samples to investigate if this technique can be used to distinguish between economic and sub-economic ore either by direct detection of these elements or by using other elements as indicators. However, the Au and Ag grades of the samples are below the detection limit

  14. AMS of natural 236U and 239Pu produced in uranium ores

    Science.gov (United States)

    Wilcken, K. M.; Barrows, T. T.; Fifield, L. K.; Tims, S. G.; Steier, P.

    2007-06-01

    The rare isotopes 236U and 239Pu are produced naturally by neutron capture in uranium ores. Here we measure 236U and 239Pu by accelerator mass spectrometry (AMS) in the same ore samples for the first time. To ensure efficient extraction of both elements and isotopic equilibrium between the 239Pu in the ore and a 242Pu spike, we developed a new sample preparation protocol. AMS has clear advantages over previous methods because it achieves better discrimination against molecular interferences with higher sensitivity and shorter counting times. Measurements of 236U and 239Pu hold considerable promise as proxy indicators of neutron flux and uranium concentration.

  15. Mineralogical and geochemical characteristics of the Noamundi-Koira basin iron ore deposits (India)

    Science.gov (United States)

    Mirza, Azimuddin; Alvi, Shabbar Habib; Ilbeyli, Nurdane

    2015-04-01

    with kaolinite and gibbsite, which make it low grade. Massive iron ores are devoid of any lamination and usually associated with BHJ and lower shale. The thickness of the massive ore layer varies with the location. The massive iron ore grades in to well-developed bedded BHJ in depth. Blue dust occurs in association with BHJ as pockets and layers. Although blue dust and friable ore are both powdery ores, and subjected to variable degree of deformation, leading to the formation of folding, faulting and joints of complex nature produce favourable channels. Percolating water play an important role in the formation of blue dust and the subterranean solution offers the necessary acidic environment for leaching of quartz from the BHJ. The dissolution of silica and other alkalis are responsible for the formation of blue dust. The friable and powdery ore on the other hand are formed by soft laminated ore. As it is formed from the soft laminated ore, its alumina content remains high similar to soft laminated ore compaired to blue dust. Mineralogy study suggests that magnetite was the principal iron oxide mineral, now a relict phase whose depositional history is preserved in BHJ, where it remains in the form of martite. The platy hematite is mainly the product of martite. The different types of iron ores are intricately related with the BHJ. Hard laminated ores, martite-goethite ore and soft laminated ore are resultant of desilicification process through the action of hydrothermal fluids. Geochemistry of banded iron-formations of the Noamundi-Koira iron ore deposits shows that they are detritus-free chemical precipitates. The mineralogical and geochemical data suggest that the hard laminated, massive, soft laminated ores and blue dust had a genetic lineage from BIF's aided with certain input from hydrothermal activity. The comparative study of major elemental composition of the basin samples and while plotting a binary diagram, it shows a relation between major oxides against

  16. Evaluation of the effectiveness of the filtration leaching for uranium recovery from uranium ore

    OpenAIRE

    2015-01-01

    The physical and chemical processes taking place in filtration leaching of uranium from uranium ore sample by sulphuric acid solution have been studied by modern physico-chemical methods (X-ray diffraction, scanning electron spectroscopy, electron probe microanalysis, optical emission spectroscope, ICP OES). Column leaching test was carried out for ore samples obtained from a uranium in-situ leaching (ISL) mining site using deluted sulphuricacid to study the evolution of various elements conc...

  17. Gold—depleted Zone and Its Metallogenic Significance,Yinshan Ore Field,Jiangxi Proveince,China

    Institute of Scientific and Technical Information of China (English)

    华仁民; 陈克荣; 等

    1994-01-01

    Based on gold analyses of 213 samples of the Shuangqiaoshan Group in an area of 225km2 with the Yinshan polymetallic ore district as the center, a depleted zone of gold is recognized around the ore district, suggesting that the Shuangqiaoshan Group may be a source bed for gold .Discus-sions were given concerning the alteration-mineralization features of the Yinshan deposit, the ore-controlling mechanism of the NE-trending fault zone and promising targets for further ore pros-pecting.

  18. 矿样中镍的二次强化浸出及X-射线衍射分析%Secondary Intensified Leaching of Nickel from Ore Sample and X-ray Diffraction Analysis

    Institute of Scientific and Technical Information of China (English)

    刘美

    2011-01-01

    A leaching process was provided for direct recovery of nickel from a nickel oxide filter slag obtained by filtering the pulp of calcination slag of Mo - Ni sulfide ores in hot water. The slag was given secondary intensifled leaching, the optimum extraction condition is:under the conditions of the solid -to -liquid ratio was set at 1:6 and the leaching temperature at 95℃, with the 15% sulfuric acid, 0.5 gram of addition agent and with the help of ultrasonic wave, after 4 hours of leaching, the secondary intensified leaching ratio of nickel was 56.37% ,the total leaching ratio was 69.34%. The phase transformation of nickel compounds in the ore is analysed preliminarily with the XRD diffraction.%采用焙烧、水浸实现了原生硫化镍钼矿中镍和钼的分离.对得到的矿渣进行二次强化浸出,考察得到的较优工艺条件为:酸浸后的矿样在固液比为1:6、浸出温度95℃、超声波振荡、浸出时间为4 h、硫酸浓度为15%和加入0.5 g添加剂条件下,镍渣中镍的二次强化浸出率为56.37%,总浸出率达到69.34%.并通过X射线衍射图谱,对矿样中镍的物相及走向进行了初步分析.

  19. The Mechanism on Biomass Reduction of Low-Grade Manganese Dioxide Ore

    Science.gov (United States)

    Zhang, Honglei; Zhu, Guocai; Yan, Hong; Li, Tiancheng; Zhao, Yuna

    2013-08-01

    The mechanism on biomass reduction of low-grade manganese dioxide ore was studied by investigating influence factors on manganese recovery degree, such as the reaction temperature, time, biomass/ore ratio, compositions of biomass, nitrogen flow rate, and particle size of raw materials, and it was further identified through analysis of gas composition in the outlet gas, X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) for the reduced sample. The results show that the reduction process involved mainly two steps: (1) The biomass was first pyrolyzed to release reductive volatiles and (2) manganese oxide ore was reacted with the reductive volatiles. By an analysis of gas composition in the outlet gas, it was also found that the ratio of biomass/ore had an important effect on the reduction mechanism. With a low biomass/ore ratio of 0.5:10, the reducing reaction of the reductive volatiles with manganese dioxide ore proceeded mainly in two stages: (1) The condensable volatiles (tar) released from biomass pyrolysis reacted with manganese oxide ore to produce reductive noncondensable gases such as hydrogen, carbon monoxide, and some light hydrocarbons; and (2) the small molecule gases further participated in the reduction. XRD pattern analysis on the reduced manganese dioxide ore revealed that the process of biomass reduction of manganese ore underwent in phases (MnO2 → Mn3O4 → MnO). The kinetics study showed the reduction process was controlled by a gas-solid reaction between biomass volatiles and manganese oxide ore with activation energy E of 53.64 kJ mol-1 and frequency factor A of 5.45 × 103 minutes-1.

  20. Rock-magnetism and ore microscopy of the magnetite-apatite ore deposit from Cerro de Mercado, Mexico

    Science.gov (United States)

    Alva-Valdivia, L. M.; Goguitchaichvili, A.; Urrutia-Fucugauchi, J.; Caballero-Miranda, C.; Vivallo, W.

    2001-03-01

    Rock-magnetic and microscopic studies of the iron ores and associated igneous rocks in the Cerro de Mercado, Mexico, were carried out to determine the magnetic mineralogy and origin of natural remanent magnetization (NRM), related to the thermo-chemical processes due to hydrothermalism. Chemical remanent magnetization (CRM) seems to be present in most of investigated ore and wall rock samples, replacing completely or partially an original thermoremanent magnetization (TRM). Magnetite (or Ti-poor titanomagnetite) and hematite are commonly found in the ores. Although hematite may carry a stable CRM, no secondary components are detected above 580°, which probably attests that oxidation occurred soon enough after the extrusion and cooling of the ore-bearing magma. NRM polarities for most of the studied units are reverse. There is some scatter in the cleaned remanence directions of the ores, which may result from physical movement of the ores during faulting or mining, or from perturbation of the ambient field during remanence acquisition by inhomogeneous internal fields within these strongly magnetic ore deposits. The microscopy study under reflected light shows that the magnetic carriers are mainly titanomagnetite, with significant amounts of ilmenite-hematite minerals, and goethite-limonite resulting from alteration processes. Magmatic titanomagnetites, which are found in igneous rocks, show trellis, sandwich, and composite textures, which are compatible with high temperature (deuteric) oxy-exsolution processes. Hydrothermal alteration in ore deposits is mainly indicated by martitization in oxide minerals. Grain sizes range from a few microns to >100 mm, and possible magnetic state from single to multidomain, in agreement with hysteresis measurements. Thermal spectra, continuous susceptibility measurements, and IRM (isothermal remanent magnetization) acquisition suggest a predominance of spinels as magnetic carriers, most probably titanomagnetites with low

  1. Test of oxidation behavior of sulfide ores at ambient temperature for fire control

    Institute of Scientific and Technical Information of China (English)

    WU Chao; LI Zi-jun; LI Ming; WU Guo-min

    2007-01-01

    The coincidence of relevant factors, e.g. oxygen absorption quantity, weight increment, water soluble iron ions and sulfate ion of sulfide ore samples in the oxidation process, was tested through experiment. Based on a large number of tests for a group sample of sulfide ores from a mine, some important conclusions were obtained. The results obtained by the investigation indicate that there is no general interpretation relative to the oxygen absorption and the formation products of sulfate ion and water soluble iron ions during the oxidation process of sulfide ores at ambient temperature. However, the weight increment of the sulfide ore samples in the oxidation process at ambient temperature has a linear relationship with the quantity of oxygen absorption.

  2. Measurement of moisture in mill feed ore

    Energy Technology Data Exchange (ETDEWEB)

    Timm, A.R.; Moench, P.; Moisel, E. (Council for Mineral Technology, Randburg (South Africa))

    1985-04-01

    The control of the moisture in the feed to a mill is very important for efficient mill operation. Water is added continuously to the ore fed to a mill to maintain a suitable mix of ore and moisture in the mill. However, problems arise because of the large variation in the moisture content of the ore, which affects the efficiency of the grind. If too little moisture is present, the mill is unable to grind the ore finely enough, creating instead a thick 'porridge' that causes the mill to choke up. On the other hand, too much moisture results in inefficient grinding because the ore is flushed through the mill too quickly. Several techniques are available for measuring moisture and Mintek undertook an investigation in an attempt to develop a reliable robust moisture meter suitable for monitoring the moisture content of ore, which include the following: neutron backscattering, infrared absorption, microwaves, capacitance and moisture as a function of conductivity.

  3. Evolution of ore deposits on terrestrial planets

    Science.gov (United States)

    Burns, R. G.

    1991-01-01

    Ore deposits on terrestrial planets materialized after core formation, mantle evolution, crustal development, interactions of surface rocks with the hydrosphere and atmosphere, and, where life exists on a planet, the involvement of biological activity. Core formation removed most of the siderophilic and chalcophilic elements, leaving mantles depleted in many of the strategic and noble metals relative to their chondritic abundances. Basaltic magma derived from partial melting of the mantle transported to the surface several metals contained in immiscible silicate and sulfide melts. Magmatic ore deposits were formed during cooling, fractional crystallization and density stratification from the basaltic melts. Such ore deposits found in earth's Archean rocks were probably generated during early histories of all terrestrial planets and may be the only types of igneous ores on Mars. Where plate tectonic activity was prevalent on a terrestrial planet, temporal evolution of ore deposits took place. Repetitive episodes of subduction modified the chemical compositions of the crust and upper mantles, leading to porphyry copper and molybdenum ores in calc-alkaline igneous rocks and granite-hosted tin and tungsten deposits. Such plate tectonic-induced mineralization in relatively young igneous rocks on earth may also have produced hydrothermal ore deposits on Venus in addition to the massive sulfide and cumulate chromite ores associated with Venusian mafic igneous rock. Sedimentary ore deposits resulting from mechanical and chemical weathering in reducing atmospheres in Archean earth included placer deposits (e.g., uraninite, gold, pyrite ores). Chromite, ilmenite, and other dense unreactive minerals could also be present on channel floors and in valley networks on Mars, while banded iron formations might underlie the Martian northern plains regions. As oxygen evolved in earth's atmosphere, so too did oxide ores. By analogy, gossans above sulfide ores probably occur on Mars

  4. Evolution of ore deposits on terrestrial planets

    Science.gov (United States)

    Burns, R. G.

    1991-01-01

    Ore deposits on terrestrial planets materialized after core formation, mantle evolution, crustal development, interactions of surface rocks with the hydrosphere and atmosphere, and, where life exists on a planet, the involvement of biological activity. Core formation removed most of the siderophilic and chalcophilic elements, leaving mantles depleted in many of the strategic and noble metals relative to their chondritic abundances. Basaltic magma derived from partial melting of the mantle transported to the surface several metals contained in immiscible silicate and sulfide melts. Magmatic ore deposits were formed during cooling, fractional crystallization and density stratification from the basaltic melts. Such ore deposits found in earth's Archean rocks were probably generated during early histories of all terrestrial planets and may be the only types of igneous ores on Mars. Where plate tectonic activity was prevalent on a terrestrial planet, temporal evolution of ore deposits took place. Repetitive episodes of subduction modified the chemical compositions of the crust and upper mantles, leading to porphyry copper and molybdenum ores in calc-alkaline igneous rocks and granite-hosted tin and tungsten deposits. Such plate tectonic-induced mineralization in relatively young igneous rocks on earth may also have produced hydrothermal ore deposits on Venus in addition to the massive sulfide and cumulate chromite ores associated with Venusian mafic igneous rock. Sedimentary ore deposits resulting from mechanical and chemical weathering in reducing atmospheres in Archean earth included placer deposits (e.g., uraninite, gold, pyrite ores). Chromite, ilmenite, and other dense unreactive minerals could also be present on channel floors and in valley networks on Mars, while banded iron formations might underlie the Martian northern plains regions. As oxygen evolved in earth's atmosphere, so too did oxide ores. By analogy, gossans above sulfide ores probably occur on Mars

  5. Up-dated ore composition data (Central ore-field, Kuznetsk Alatau

    Directory of Open Access Journals (Sweden)

    Bushmanov A.

    2016-01-01

    Full Text Available Applying scanning electron microscope (SEM, energy-dispersive microanalyzer and X-ray ray fluorescence microscope the ore mineral composition in Central gold-ore field ore field (Kuznetsk Alatau was investigated. Eleven new minerals were detected in this ore field. The differentiated behavior of mineral formation stages in veinsand near-veined beresites was determined. The composition of native gold was studied, as well as the distribution of trace elements in pyrite.

  6. Phases transformation of nickel lateritic ore during dehydration

    Directory of Open Access Journals (Sweden)

    Huang Q.

    2011-01-01

    Full Text Available The high magnesium nickel laterite ore need first be dehydrated if it is treated by the pirometallurgical means. The nickel laterite ore was dehydrated in a laboratory scale sintering pot in this study. The dehydration mechanism was studied by using the thermo-gravimetric (TG tests, differential thermal analysis (DTA, and X-ray diffraction (XRD experiments. The measurements indicated that chlorite (Fe,Mg,Al6(Si,Al4O10(OH8 and serpentine Mg21Si12O28(OH34H2O are the primary phases, while FeO(OH and (Fe,Mg,3Si4O10(OH2 are the minor phases in the ore. The water in the ore can be divided as free water, crystal water, and hydroxyl group. During the heating process, the temperature range for the removal of the free water is 25~140˚C, for the crystal water it is 200~480 ˚C, and for the hydroxyl group it is 500~800˚C. The experiments with various coal dosages show that the temperatures of off-gas and burden increase with an increase in coal dosage. The sinter samples were analyzed using XRD. The results demonstrated that olivine (Mg,Fe2SiO4 and spinel MgFe2O4 are the main bonding phases.

  7. Hageri alustas oreli taastamisega / Inge Põlma

    Index Scriptorium Estoniae

    Põlma, Inge

    2009-01-01

    1851. aastal eesti orelimeistri Carl Tantoni valmistatud ja 1892. aastal Gustav Terkmanni poolt kohendatud Hageri Lambertuse kiriku oreli restaureerimisest, ekspertiisi tegi rootsi organist Göran Grahn

  8. Microwave enhanced recovery of nickel-copper ore: communition and floatability aspects.

    Science.gov (United States)

    Henda, R; Hermas, A; Gedye, R; Islam, M R

    2005-01-01

    A study describing the effect of microwave radiation, at a frequency of 2450 MHz, on the processes of communication and flotation of a complex sulphide nickel-copper ore is presented. Ore communication has been investigated under standard radiation-free conditions and after ore treatment in a radiated environment as a function of ore size, exposure time to radiation, and microwave power. The findings show that communication is tremendously improved by microwave radiation with values of the relative work index as low as 23% at a microwave power of 1.406 kW and after 10 s of exposure time. Communication is affected by exposure time and microwave power in a nontrivial manner. In terms of ore floatability, the experimental tests have been carried out on a sample of 75 microm in size under different exposure times. The results show that both ore concentrate recoveries and grades of nickel and copper are significantly enhanced after microwave treatment of the ore with relative increases in recovered concentrate, grade of nickel, and grade of copper of 26 wt%, 15 wt%, and 27%, respectively, at a microwave power of 1330 kW and after 30 s of exposure time.

  9. Magnetic mineralogy of the Hongqiling Cu-Ni sulphide deposit:Implications for ore genesis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Pyrrhotite is one of the common ore minerals in Cu-Ni sulphide deposits, but only monoclinic pyrrhotite is ferromagnetic at room temperature. X-ray and EPA analyses reveal that most pyrrhotite forming sideronitic texture in the Hongqiling Cu-Ni sulphide deposit is monoclinic, but that in the massive ore is a mixture of monoclinic and hexagonal pyrrhotites. Differential thermal and magneticthermogravimetric analyses of massive ore indicate a magnetic transition and heat absorption at 323℃, suggesting that this temperature is the thermomagnetic and phase transition point of pyrrhotite. For massive pyrrhotite ores heated at 400℃ for 30 h and then quenched by cool water, the monoclinic pyrrhotite (mpo) transforms completely into the hexagonal pyrrhotite (hpo). However, all the pyrrhotites resulting from slow cooling of the sample in air are mpo. These results indicate that transformation between hpo and mpo depends upon the cooling rate. Therefore, massive ores in this deposit might have been formed via rapid cooling of ore melts. On the other hand, it is significant to study the effect of the ratio of the magnetite in total ores on the genesis of magmatic Cu-Ni suphide deposits.

  10. Phase transformations of siderite ore by the thermomagnetic analysis data

    Science.gov (United States)

    Ponomar, V. P.; Dudchenko, N. O.; Brik, A. B.

    2017-02-01

    Thermal decomposition of Bakal siderite ore (that consists of magnesium siderite and ankerite traces) was investigated by thermomagnetic analysis. Thermomagnetic analysis was carried-out using laboratory-built facility that allows automatic registration of sample magnetization with the temperature (heating/cooling rate was 65°/min, maximum temperature 650 °C) at low- and high-oxygen content. Curie temperature gradually decreases with each next cycles of heating/cooling at low-oxygen content. Curie temperature decrease after 2nd cycle of heating/cooling at high-oxygen content and do not change with next cycles. Final Curie temperature for both modes was 320 °C. Saturation magnetization of obtained samples increases up to 20 Am2/kg. The final product of phase transformation at both modes was magnesioferrite. It was shown that intermediate phase of thermal decomposition of Bakal siderite ore was magnesiowustite.

  11. Iron from Zealandic bog iron ore -

    DEFF Research Database (Denmark)

    Lyngstrøm, Henriette Syrach

    2011-01-01

    og geologiske materiale, metallurgiske analyser og eksperimentel arkæologiske forsøg - konturerne af en jernproduktion med udgangspunkt i den sjællandske myremalm. The frequent application by archaeologists of Werner Christensen’s distribution map for the occurrence of bog iron ore in Denmark (1966...... are sketched of iron production based on bog iron ore from Zealand....

  12. The Luster of Iron Ore Prices

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    China battles its way out of an iron ore stalemate by finding alternative supplier After months of seesawing, China’s iron ore negotiators appear to be breaking through the tight encirclement of suppliers. On August 17, the China Iron and Steel Association (CISA) announced that Fortescue

  13. Fuzzy Comprehensive Appraisal of Concealed Ore Deposits

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper, the transformation from the fuzzy to the accurate process is exemplified by the Jiaodong gold ore deposits concentrated region where the mathematical analysis is used to appraise and forecast regional concealed gold ore deposits. In this sense, this paper presents a new way to the appraisal of the non-traditional mineral resources.

  14. Biomass for iron ore sintering

    Energy Technology Data Exchange (ETDEWEB)

    Zandi, M.; Martinez-Pacheco, M.; Fray, T.A.T. [Corus Research Development & Technology, Rotherham (United Kingdom)

    2010-11-15

    Within an integrated steelworks, iron ore sinter making is an energy intensive process. In recent years, biomass is becoming an attractive alternative source of energy to traditional fossil fuels such as coal. In this study, commercially available biomass materials suited to sinter making have been identified as an alternative source of fuel to coke breeze. Olive residues, sunflower husk pellets, almond shells, hazelnut shells and Bagasse pellets have been characterised and prepared for sintering. A laboratory sinter pot has been employed for studying sintering behaviour of biomass material. On average, the calorific values of selected biomass materials, on a dry basis, are about 65% of dry coke breeze. It was found that less of this energy would be available in sinter making due to the evaporation of some of the volatile matter ahead of the flame front. At a replacement rate of 25%, the crushed sunflower husk pellets showed the closest thermal profile to that of coke breeze alone in the size range of -0.8 to +0.6 mm. A specification of less than 1 mm has been recommended for the studied biomass materials when co-firing biomass with coke breeze for iron ore sintering.

  15. THE SOLUBILITY OF MILAS BAUXITE ORE IN SULPHURIC ACI

    Directory of Open Access Journals (Sweden)

    Mustafa GULFEN

    2001-06-01

    Full Text Available The effects of calcination conditions,sulphuric acid concentrations and dissolvingtemperature and period as parameters to thesolubility of the bauxite ore from Gobekdagı reservesin Mugla-Milas region were investigated. The bauxitesamples were calcined in different periods at differenttemperatures. Then the solubility of the calcinedbauxite samples in sulphuric acid solution wasexamined. Dissolving activation energy (Ea wascalculated using the optimum kinetics equation andthe results obtained from the solubility studiesexamined dissolving temperatures and periods

  16. Thickening and rheological properties of slurries as functions of the oxidized nickel ore composition

    Science.gov (United States)

    Serova, N. V.; Olyunina, T. V.; Lysykh, M. P.; Ermishkin, V. A.; Smirnova, V. B.

    2016-07-01

    The thickening and rheological properties of ore slurries and pulps after autoclave sulfuric acid leaching are analyzed as a function of the phase composition of oxidized nickel ore. Experiments have been carried out with samples of ferrous, silicate and combined ores. The initial concentration of the ore slurries is ˜28%. Higher values of thickening properties (thickening rate of 1.3 m/day, thickened layer concentration of 54%) are exhibited by the ferrous ore slurry and the pulp after its leaching (thickening rate of 0.9 m/day, thickened layer concentration of 42%). The thickening rate of silicate ore slurry is 0.15-0.2 m/day, the thickened layer concentration is 40-45%. The thickening properties of the pulp after autoclave sulfuric acid leaching of silicate ore strongly depend on the consumption of sulfuric acid. The thickening properties of combined ore and pulps after its leaching deteriorate with increase in the content of silicon dioxide in the ore. In terms of the rheological properties, all slurries are pseudoplastic systems. Poorly thickening slurries are characterized by a high dynamic yield stress (up to 7 Pa) and apparent plastic and effective viscosities. The effective viscosity at the equivalent shear rate corresponding to the mixer rotation rate in laboratory autoclave reaches 34 × 10-3 Pa s. Boundary values are determined in rheological constants with regard to the thickening properties. For instance, if the dynamic yield point is 1.0 Pa, the thickening rate decreases from 0.075 m/day to zero. The thickening and rheological properties are found to depend on the particle size of solid phase and its surface properties.

  17. The potential for ore and industrial minerals in the Forsmark area

    Energy Technology Data Exchange (ETDEWEB)

    Lindroos, Hardy [MIRAB Mineral Resurser AB, Uppsala (Sweden); Isaksson, Hans; Thunehed, Hans [GeoVista AB, Luleaa (Sweden)

    2004-03-01

    A survey has been made of existing information concerning the potential for ore and industrial minerals in and near the candidate area for a deep repository in Forsmark. A deep repository for spent nuclear fuel should not be located in a rock type or an area where mineral extraction might be considered in the future, since this would make it impossible to exploit this natural resource. Avoiding such areas reduces the risk that people in the future will come into contact with the deep repository through mineral prospecting or mining activities. The survey has made use of all the geoscientific information that was compiled in the more regional investigations in Oesthammar Municipality in 1996-97. In cooperation with the Geological Survey of Sweden (SGU), a new, more detailed mineral resources map has been prepared. The map shows areas with an ore potential that may be unsuitable or unfavourable for siting of a deep repository. The results of the recently completed geophysical helicopter surveys of the Forsmark area are presented in a special chapter. The judgement of the area's ore potential is in part based on the geophysical evaluation of these measurements. Furthermore, the survey obtained information from ongoing deep drillings from the site investigation in Forsmark. In order to better be able to judge the ore potential, the survey has initiated a geochemical investigation of activated soil samples, plus an ore geology sampling of a section in the deep borehole KFM02A, where a hydrothermally altered zone was detected in 2003.The first results from these samplings are presented in the report, which also discusses prospecting efforts in the area as well as relevant Swedish mining legislation. Some suggestions are made for further ore geology investigations. The mineral resources map shows that there is an elongate northwest-southeast zone south and southwest of the candidate area which has a potential for skarn iron ore, and possibly for copper and zinc

  18. Uranium recovery from Uro area phosphate ore, Nuba Mountains, Sudan

    Directory of Open Access Journals (Sweden)

    Abdelmajid A. Adam

    2014-11-01

    Full Text Available This study was carried out in a laboratory scale to recover uranium from Uro area phosphate ore in the eastern part of Nuba Mountains in Sudan. Phosphate ore samples were collected, and analyzed for uranium abundance. The results showed that the samples contain a significant concentration of uranium with an average of 310.3 μg/g, which is 2.6 times higher than the world average of phosphate. The green phosphoric acid obtained from the samples was found to contain uranium in the range of 186–2049 μg/g, with an average of 603.3 μg/g, and about 98% of uranium content of the phosphate ore was rendered soluble in the phosphoric acid. An extraction process using 25% tributylphosphate, followed by stripping process using 0.5 M sodium carbonate reported that more than 98% of uranium in the green phosphoric acid exists as uranyl tricarbonate complex, moreover, sodic decomposition using 50% sodium hydroxide showed that about 98% of the uranium was precipitated as sodium diuranate concentrate that is known as the yellow cake (Na2U2O7. Further purification and calcinations of the yellow cake led to the formation of the orange powder of uranium trioxide (UO3. The chemical analysis of the obtained uranium concentrates; yellow cake and uranium trioxide proved their nuclear purity and that they meet the standard commercial specification. The obtained results proved that uranium from Uro phosphate ore was successfully recovered as uranium trioxide with an overall recovery percentage of 93%.

  19. REE Characteristics of Microfine Disseminated Gold Ores in Danzai,Guizhou

    Institute of Scientific and Technical Information of China (English)

    陈庆年; 周丕康; 等

    1998-01-01

    Described in this paper are the fundamental characteristics of mineralization of gold ores in the Sandu-Danzhai Hg-Sb-Au ore belt of Guizhou Province,Through systematic sampling of the industrial orebody and alteration zone,the total amount of the rare-earth elements,that of the light rare-earth elements,Eu depletion and other parameters are clarified.There have been distinguished two types of REE distribution patterns:the"Clay type"and the "quartz type" .High-grade orebodies are closely related with silicification,illitization and pyritization.The seven-component diagram of the REEs of even numbers in the periodic table(Bal-asov,1966)is capable of distinguishing ore-bearing from ore-barren deposits.

  20. Advances in research of sulphide ore textures and their implications for ore genesis

    Institute of Scientific and Technical Information of China (English)

    GU Lianxing; ZHENG Yuanchuan; TANG Xiaoqian; WU Changzhi; HU Wenxuan

    2006-01-01

    Important advances in research of sulphide ore textures in recent years have deepened our understanding of ore genesis of related mineral deposits. Pressure solution of sulphide minerals has been suggested as a mechanism for remobilization of ore materials,whereas pressure solution of the gangues is believed to raise the grade of the primary ores. We have known that precipitation of base metal sulphides from fluids prefers crystal and crack surfaces of pyrite to form overgrowth. Therefore, pyrite-bearing embryo beds in a sedimentary sequence can be acted as effective crystal seed beds and are favorable for fluid overprinting to form huge statabound deposits. Texture studies of various sulphides can be used to interpret the entire history of sedimentation, diagenesis, deformation and metamorphism of the ores. The study of chalcopyrite disease in sphalerite has brought about the idea of zone refining, and given a new explanation to metal zonation in massive sulphide deposits. Ductile shearing of sulphide ores may form ore mylonites, which will become oreshoots enriched in Cu, Au and Ag during late-stage fluid overprinting. Despite that various modern analytical techniques are being rapidly developed, ore microscopy remains to be an unreplaceable tool for ore geologists. Combined with these modern techniques, this tool will help accelerate the development of theories on ore genesis.

  1. Nitrile O-ring Cracking: A Case of Vacuum Flange O-ring Failures

    Energy Technology Data Exchange (ETDEWEB)

    Dees, Craig

    2016-07-01

    A review of recent nitrile O-ring failures in ISO-KF vacuum flange connections in glovebox applications is presented. An investigation of a single “isolated” o-ring failure leads to the discovery of cracked nitrile o-rings in a glovebox atmospheric control unit. The initial cause of the o-ring failure is attributed to ozone degradation. However, additional investigation reveals nitrile o-ring cracking on multiple gloveboxes and general purpose piping, roughly 85% of the nitrile o-rings removed for inspection show evidence of visible cracking after being in service for 18 months or less. The results of material testing and ambient air testing is presented, elevated ozone levels are not found. The contributing factors of o-ring failure, including nitrile air sensitivity, inadequate storage practices, and poor installation techniques, are discussed. A discussion of nitrile o-ring material properties, the benefits and limitations, and alternate materials are discussed. Considerations for o-ring material selection, purchasing, storage, and installation are presented in the context of lessons learned from the nitrile o-ring cracking investigation. This paper can be presented in 20 minutes and does not require special accommodations or special audio visual devices.

  2. Correlations among factors of sulfide ores in oxidation process at ambient temperature

    Institute of Scientific and Technical Information of China (English)

    吴超; 李孜军; 周勃

    2004-01-01

    Spontaneous combustion is one of the serious problems in the mining of sulfide ore deposits. The relevant factors, e. G. Oxygen absorption quantity, mass increase, contents of water soluble iron ions and sulfate ion of sulfide ore samples in the oxidation process were investigated both in theory and experiment. The results from the investigation show that there is no general interpretation relation among the oxygen absorption quantity, the contents of sulfate ion and water soluble iron ions during the oxidation process of sulfide ores at ambient temperature.However, there is a linear relationship between the mass increase of the sulfide ore samples in the oxidation process at ambient temperature and the quantity of oxygen absorption. Therefore, the simple and cheap mass scaling method is suitable for predicting the oxygen absorption performance of sulfide ores at ambient temperature in place of the expensive and complicated chemical method used hitherto. Furthermore, combined with other items of breeding-fire test, the mass increase potential can also be used to predict the spontaneous combustion tendency of sulfide ores.

  3. Ore-forming fluids in the Dongping gold deposit, northwestern Hebei Province

    Institute of Scientific and Technical Information of China (English)

    FAN; Hongrui

    2001-01-01

    : 1435-1444.[11]Schwartz, M. O., Determining phase volumes of mixed CO2-H2O inclusions using microthermometric measurements, Mineral Deposita, 1989, 24: 43-47.[12]Brown, P. E., Hagemann, S. G., MacFlincor and its application to fluids in Archean lode-gold deposits, Geochimica et Cosmochimica Acta, 1995, 59: 3943-3952.[13]Fan Hongrui, Xie Yihan, Zhao Rui et al., Dual origins of Xiaoqinling gold-bearing quartz veins: Fluid inclusion evidences, Chinese Science Bulletin, 2000, 45(15): 1424-1430.[14]Chen Yanjing, Li Chao, Zhang Jing et al., Sr and O isotopic characteristics of porphyries in the Qinling molybdenum de-posit belt and their implication to genetic mechanism and type, Science in China, Ser. D, 2000, 43 (supp.): 82-94.[15]Zhang Fuxin, Chen Yanjing, Li Chao et al., Geological and geochemical character and genesis of the Jinlongshan-Qiuling gold deposits in Qinling orogen: Metallogenic mechanism of the Qinling-pattern Carlin-type gold deposits, Science in China, Ser. D, 2000, 43(supp.): 95-107.[16]Chen Yanjing, Guo Guangjun, Li Xin, Metallogenic geodynamic background of gold deposits in Granite-greenstone ter-rains of North China craton, Science in China Ser. D, 1998, 41(2): 113-120.[17]Clayton, R. N., Oxygen isotope exchange between quartz and water, J. Geophys. Res., 1972, 77: 3057-3607.[18]Zhang Ligang, Cheng Zhengshen, Liu Jingxiu et al., Two Stage Water-rock Interaction and Prospecting Cases, Beijing: Geological Publishing House, 1995, 1-231.[19]Jiang Sihong, Nie Fengjun, 40Ar-39Ar geochronology of the Shuiquangou alkaline complex and related gold deposits, Northwestern Hebei, China, Geological Review, 2000, 46(6): 621-627.[20]Taylor, H. P., Oxygen and hydrogen isotope relationships, in Barnes H L(ed.), Geochemistry of Hydrothermal Ore Depos-its, 2nd ed., New York: John Wiley & Sons, 1979, 236-277.[21]Yardley, B. W. D., Post-metamorphic gold-quartz veins from N.W Italy: The composition and origin of the ore fluid, Min

  4. Development of Technology for Enrichment of Silver Containing Ores

    Science.gov (United States)

    Shekiladze, Asmati; Kavtelashvili, Otari; Bagnashvili, Mamuka

    2016-10-01

    The progress of Georgian economics is substantially associated with a development of new deposits of mineral resources. Among them is the David-Gareji deposit where at present the intensive searching geological works are performed. The work goal involves the elaboration of the technology for processing of silver-containing quartz-barite ores. Without its development the mining of more valuable gold-polymetallic ores is impossible. Because of ore complexity silver and barite are considered in a common technological aspect. The investigations were carried out on the representative samples of quartz-barite ores containing 78-88 g/ton of silver and 27-29 % of silver is a nugget in the form of the simple sulphides and chlorides. The ore is characterized by fine coalescence of barite and ore-generating minerals. Non-ferrous metals haven't any industrial value because of their very low content. Therefore, for the processing of the ores under study the direct selective scheme of flotation enrichment was chosen and the formula of optimal reagent regime was elaborated. Potassium xanthogenate is used as a collector for flotation of silver minerals and pine oil- as a foaming agent. The effect of the pulp - pH and medium temperature on silver flotation was studied. It was established that the silver is actively floats in neutral medium. For barite flotation the various collectors were tested: sulfidezid cotton oil-soap stock, soaps of fatty acids and alkyl sulphates of C12 - C16 row, among the “Baritol” is the most efficient one. Depression of the barren rock was carried out by liquid glass in alkaline medium. The effect of pulp pH on barite flotation has been investigated. The best results were obtained at pH=8.5. The increase of the pulp alkalinity has no essential effect on the indexes of the barite enrichment. Conditional concentrate of the barite is obtained by two fold purification of the main flotation concentrate by the addition of the liquid glass to the re

  5. Sampling

    CERN Document Server

    Thompson, Steven K

    2012-01-01

    Praise for the Second Edition "This book has never had a competitor. It is the only book that takes a broad approach to sampling . . . any good personal statistics library should include a copy of this book." —Technometrics "Well-written . . . an excellent book on an important subject. Highly recommended." —Choice "An ideal reference for scientific researchers and other professionals who use sampling." —Zentralblatt Math Features new developments in the field combined with all aspects of obtaining, interpreting, and using sample data Sampling provides an up-to-date treat

  6. Oolitic ores in the Bakchar iron-ore cluster (Tomsk Oblast)

    Science.gov (United States)

    Rudmin, M. A.; Mazurov, A. K.

    2016-12-01

    Oolitic iron ores are typified, and their morphology and composition are studied. Special attention is focused on the character of distribution of valuable and harmful admixtures and determination of the principal minerals concentrating these elements. As a result of this study, three types of ores are identified, such as "loose" ores, cemented ores with glauconite-chlorite-clay cement, and well-cemented ores with siderite cement. The morphology and composition of the ore oolites are characterized. The forms of occurrence of calcium phosphates (anapaite) and phosphates of rare-earth elements (monazite, cularite) that are related to the harmful phosphorus admixture are described. According to the analysis of the elemental composition, the fractions of (-1…+0.2) and (-1…+0.1) mm in the western and eastern segments, respectively, may be promising for processing.

  7. Geological Characteristics of Epithermal Ore Concentrated Areas and Epithermal Ore Deposits in China

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The epithermal ore concentrated area is located in Southwestern China. We systematically study the regional geological characteristics such as the basement of Proterozoic, the capping bed, Moho, geothermal feature and tectonics, and discuss the relationship between distributed characteristics of the epithermal ore deposits and ore-control factors in this paper. It is concluded that the conditions, under which the epithermal ore deposits form, are huge thick basement of Proterozoic, long-time and wide-scope developed capping bed and weak magmatic activity. The basement of Proterozoic that enriches volcanic matters and carbon and the carbonaceous-bearing and paleo-pool-bearing capping bed provides main ore source. The large and deep faults and paleopool accordance with gravity anomaly gradient control the distribution of epithermal ore deposits. The lithologic assembles of microclastic rocks and carbonate rocks in the capping bed provide spaces of ore precipitation and create conditions of ore precipitation. The coincidence of many geological factors above forms the epithermal ore concentrated area.

  8. The sources of our iron ores. II

    Science.gov (United States)

    Burchard, E.F.

    1933-01-01

    In this instalment** the iron ore deposits of the Lake Superior States, which normally furnish about 80 per cent, of the annual output of the United States, are described together with historical notes on discovery and transportation of ore. Deposits in the Mississippi Valley and Western States are likewise outlined and the sources of imported ore are given. Reviewing the whole field, it is indicated that the great producing deposits of the Lake Superior and southern Appalachian regions are of hematite in basin areas of sedimentary rocks, that hydrated iron oxides and iron carbonates are generally found in undisturbed comparatively recent sediments, and that magnetite occurs in metamorphic and igneous rocks; also that numerical abundance of deposits is not a criterion as to their real importance as a source of supply. Statistics of production of iron ore and estimates of reserves of present grade conclude the paper.

  9. Understanding Lateritic Ore Agglomeration Behaviour as a ...

    African Journals Online (AJOL)

    user

    istics, low grade lateritic ores require more aggressive but costly chemical and hydrometallurgical techniques (e.g., leaching in ... Isothermal, batch agglomeration tests involving 30 and 44 % w/w sulphuric acid ... *Loss of ignition. Table 2: ...

  10. Research of Geochemical Associations of Nephelin Ores

    Science.gov (United States)

    Vulf, M.; Simonov, K.; Sazonov, A.

    The instant paper concerns research of distribution petrogenic chemical members in urtit ore body of Kia-Shaltyrsk deposit. Rocks of the deposit are ore for producing alum earth. Actuality of the subject based on outlooks of detection noble metal ore-bearing (Au, Pt, Pd, Rh, Ru) in alkaline rocks of Siberia, including rocks of Kia-Shaltyrsk deposit (Kuznetsk Alatau). The main purpose of analysis of distribution of members is directed to detection of a non-uniformity of distribution of substance and segments enriched with alum earth and noble members. The basic solved problems are following: o Creation regression models of ore body; o Definition of cumulative distribution functions of members in a contour of ore body; o The analysis of the obtained outcomes in geologic terms. For construction regression models the full-scale data was used, which was presented by the results of the spectral and silicate analyses of gold and petrogenic members containing 130 assays arranged in ore body. A non-linear multiparameter model of the ore body based on components of nephelin ore using neural net approach was constructed. For each member the corresponding distribution function is produced. The model is constructed on the following members: Au, Al2O3, SiO2, Fe2O3, CaO, MgO, SO3, R2O ((Na2O+K2O) -1) and losses of burning. The error of model forecasting membersS concentrations was from 0.02 up to 20%. Large errors basically connected with assays located near contact of ore body and ad- jacent strata or with very high concentrations of members; also they can be connected with different genesis of rocks or superposition of other processes. The analysis of concentrations of members and normalised absolute errors of the fore- cast has shown, that all members can be sectioned into two groups: first: Al2O3, SiO2, R2O, Fe2O3 and second: Au, losses of burning, CaO, MgO, SO3. The distribution of 1 gold is tightly connected with calcium and losses of burning and spatially linked with zones

  11. Extracting phosphoric iron under laboratorial conditions smelting bog iron ores

    Science.gov (United States)

    Török, B.; Thiele, A.

    2013-12-01

    In recent years it has been indicated by archaeometric investigations that phosphoric-iron (P-iron, low carbon steel with 0,5-1,5wt% P), which is an unknown and unused kind of steel in the modern industry, was widely used in different parts of the world in medieval times. In this study we try to explore the role of phosphorus in the arhaeometallurgy of iron and answer some questions regarding the smelting bog iron ores with high P-content. XRF analyses were performed on bog iron ores collected in Somogy county. Smelting experiments were carried out on bog iron ores using a laboratory model built on the basis of previously conducted reconstructed smelting experiments in copies of excavated furnaces. The effect of technological parameters on P-content of the resulted iron bloom was studied. OM and SEM-EDS analyses were carried out on the extracted iron and slag samples. On the basis of the material analyses it can be stated that P-iron is usually extracted but the P-content is highly affected by technological parameters. Typical microstructures of P-iron and of slag could also be identified. It could also be established that arsenic usually solved in high content in iron as well.

  12. Hydrothermal zebra dolomite in the Great Basin, Nevada--attributes and relation to Paleozoic stratigraphy, tectonics, and ore deposits

    Science.gov (United States)

    Diehl, S.F.; Hofstra, A.H.; Koenig, A.E.; Emsbo, P.; Christiansen, W.; Johnson, Chad

    2010-01-01

    In other parts of the world, previous workers have shown that sparry dolomite in carbonate rocks may be produced by the generation and movement of hot basinal brines in response to arid paleoclimates and tectonism, and that some of these brines served as the transport medium for metals fixed in Mississippi Valley-type (MVT) and sedimentary exhalative (Sedex) deposits of Zn, Pb, Ag, Au, or barite. Numerous occurrences of hydrothermal zebra dolomite (HZD), comprised of alternating layers of dark replacement and light void-filling sparry or saddle dolomite, are present in Paleozoic platform and slope carbonate rocks on the eastern side of the Great Basin physiographic province. Locally, it is associated with mineral deposits of barite, Ag-Pb-Zn, and Au. In this paper the spatial distribution of HZD occurrences, their stratigraphic position, morphological characteristics, textures and zoning, and chemical and stable isotopic compositions were determined to improve understanding of their age, origin, and relation to dolostone, ore deposits, and the tectonic evolution of the Great Basin. In northern and central Nevada, HZD is coeval and cogenetic with Late Devonian and Early Mississippian Sedex Au, Zn, and barite deposits and may be related to Late Ordovician Sedex barite deposits. In southern Nevada and southwest California, it is cogenetic with small MVT Ag-Pb-Zn deposits in rocks as young as Early Mississippian. Over Paleozoic time, the Great Basin was at equatorial paleolatitudes with episodes of arid paleoclimates. Several occurrences of HZD are crosscut by Mesozoic or Cenozoic intrusions, and some host younger pluton-related polymetallic replacement and Carlin-type gold deposits. The distribution of HZD in space (carbonate platform, margin, and slope) and stratigraphy (Late Neoproterozoic Ediacaran-Mississippian) roughly parallels that of dolostone and both are prevalent in Devonian strata. Stratabound HZD is best developed in Ediacaran and Cambrian units, whereas

  13. Biomining: metal recovery from ores with microorganisms.

    Science.gov (United States)

    Schippers, Axel; Hedrich, Sabrina; Vasters, Jürgen; Drobe, Malte; Sand, Wolfgang; Willscher, Sabine

    2014-01-01

    Biomining is an increasingly applied biotechnological procedure for processing of ores in the mining industry (biohydrometallurgy). Nowadays the production of copper from low-grade ores is the most important industrial application and a significant part of world copper production already originates from heap or dump/stockpile bioleaching. Conceptual differences exist between the industrial processes of bioleaching and biooxidation. Bioleaching is a conversion of an insoluble valuable metal into a soluble form by means of microorganisms. In biooxidation, on the other hand, gold is predominantly unlocked from refractory ores in large-scale stirred-tank biooxidation arrangements for further processing steps. In addition to copper and gold production, biomining is also used to produce cobalt, nickel, zinc, and uranium. Up to now, biomining has merely been used as a procedure in the processing of sulfide ores and uranium ore, but laboratory and pilot procedures already exist for the processing of silicate and oxide ores (e.g., laterites), for leaching of processing residues or mine waste dumps (mine tailings), as well as for the extraction of metals from industrial residues and waste (recycling). This chapter estimates the world production of copper, gold, and other metals by means of biomining and chemical leaching (bio-/hydrometallurgy) compared with metal production by pyrometallurgical procedures, and describes new developments in biomining. In addition, an overview is given about metal sulfide oxidizing microorganisms, fundamentals of biomining including bioleaching mechanisms and interface processes, as well as anaerobic bioleaching and bioleaching with heterotrophic microorganisms.

  14. Mechanism of mechanical activation for sulfide ores

    Institute of Scientific and Technical Information of China (English)

    HU Hui-ping; CHEN Qi-yuan; YIN Zhou-lan; HE Yue-hui; HUANG Bai-yun

    2007-01-01

    Structural changes for mechanically activated pyrite, sphalerite, galena and molybdenite with or without the exposure to ambient air, were systematically investigated using X-ray diffraction analysis(XRD), particle size analysis, gravimetrical method, X-ray photo-electron spectroscopy(XPS) and scanning electron microscopy(SEM), respectively. Based on the above structural changes for mechanically activated sulfide ores and related reports by other researchers, several qualitative rules of the mechanisms and the effects of mechanical activation for sulfide ores are obtained. For brittle sulfide ores with thermal instability, and incomplete cleavage plane or extremely incomplete cleavage plane, the mechanism of mechanical activation is that a great amount of surface reactive sites are formed during their mechanical activation. The effects of mechanical activation are apparent. For brittle sulfide ores with thermal instability, and complete cleavage plane, the mechanism of mechanical activation is that a great amount of surface reactive sites are formed, and lattice deformation happens during their mechanical activation. The effects of mechanical activation are apparent. For brittle sulfide ores with excellent thermal stability, and complete cleavage plane, the mechanism of mechanical activation is that lattice deformation happens during their mechanical activation. The effects of mechanical activation are apparent. For sulfide ores with high toughness, good thermal stability and very excellent complete cleavage plane, the mechanism of mechanical activation is that lattice deformation happens during their mechanical activation, but the lattice deformation ratio is very small. The effects of mechanical activation are worst.

  15. How Many Ore-Bearing Asteroids?

    CERN Document Server

    Elvis, Martin

    2013-01-01

    A simple formalism is presented to assess how many asteroids contain ore, i.e. commercially profitable material, and not merely a high concentration of a resource. I apply this formalism to two resource cases: platinum group metals (PGMs) and water. Assuming for now that only Ni-Fe asteroids are of interest for PGMs, then 1% of NEOs are rich in PGMs. The dearth of ultra-low delta-v (= US$1 B and the population of near-Earth objects (NEOs) larger than 100 m diameter is ~20,000 (Mainzer et al. 2011) the total population of PGM ore-bearing NEOs is roughly 10. I stress that this is a conservative and highly uncertain value. For example, an order of magnitude increase in PGM ore-bearing NEOs occurs if delta-v can as large as 5.7 km s-1. Water ore for utilization in space is likely to be found in ~1/1100 NEOs. NEOs as small as 18 m diameter can be water-ore-bodies because of the high richness of water (~20%) expected in ~25% of carbonaceous asteroids, bringing the number of water-ore-bearing NEOs to ~9000 out of th...

  16. Ores and Climate Change - Primary Shareholders

    Science.gov (United States)

    Stein, Holly J.; Hannah, Judith L.

    2015-04-01

    Many in the economic geology community concern themselves with details of ore formation at the deposit scale, whether tallying fluid inclusion data to get at changes in ore-forming fluids or defining structures that aid and abet mineralization. These compilations are generally aimed at interpretation of events at the site of ore formation, with the goal being assignment of the deposit to a sanctioned ore deposit model. While providing useful data, this approach is incomplete and does not, by itself, serve present-day requirements for true interdisciplinary science. The ore-forming environment is one of chaos and disequilibrium at nearly all scales (Stein, 2014). Chaos and complexity are documented by variably altered rocks, veins or disseminated mineralization with multi-generational fluid histories, erratic and unusual textures in host rocks, and the bitumen or other hydrocarbon products entwined within many ore deposits. This should give pause to our drive for more data as a means to find "the answer". The answer lies in the kind of data collected and more importantly, in the way we interpret those data. Rather than constructing an ever-increasing catalog of descriptive mutations on sanctioned ore deposit models (e.g., IOGC or Iron-Oxide Copper Gold deposits), the way forward is to link source and transport of metals, sulfur, and organic material with regional and ultimately whole Earth chemical evolution. Important experimental work provides chemical constraints in controlled and behaved environments. To these data, we add imagination and interpretation, always tying back to field observations. In this paper, several key points are made by way of ore deposit examples: (1) many IOCG deposits are outcomes of profound changes in the chemistry of the Earth's surface, in the interplay of the atmosphere, hydrosphere, biosphere, and lithosphere; (2) the redox history of Fe in deep earth may be ultimately expressed in the ore-forming sequence; and (3) the formation of

  17. PREDICTION OF LOCATION OF HIDDEN ORE DEPOSITS IN THE AGED ORE FIELDS:AN EXAMPLE FROM FENGHUANGSHAN ORE FIELD,TONGLING,CHINA

    Institute of Scientific and Technical Information of China (English)

    LIU; Liang-ming; PENG; Sheng-lin; YIANG; Qun-zhou; SHAO; Yong-jun; WANG; Zhi-qiang

    2001-01-01

    This paper discusses the strategy for successfully predicting the location of potential hidden ore bodies in aged ore field,and presents the result of location prediction of hidden ore bodies in Fenghuangshan ore field,Tongling.Innovative conceptual targeting procedures based on a genetic understanding of mineralization systems,carefully geological investigation and correct deduction,together with new geochemical and geophysical technology and integrating of comprehensive information are all very important for the successful prediction.In the aged Fenghuangshan ore field,through researching by application of the metallogenic theory of polygenetic compound ore deposits and triple-frequency induced polarization method and exploration tectono-geochemical method,we predicted location and quality of hidden ore bodies.According to the prediction,hidden high quality Cu-Au ore bodies of skarn type and porphyry type have been discovered.

  18. Natural Activities of 238U, 232Th and 40K in Manganese Ore

    Directory of Open Access Journals (Sweden)

    H. A. Abel-Ghany

    2010-01-01

    Full Text Available Problem statement: Manganese ore is widely used in much industries. Such as ore contain natural radioactive nuclides at various concentrations. If this ore contain high concentrations of natural radioactive nuclides, workers handling them might be exposed to significant levels of radiation. Therefore it is important to determine the radioactive nuclides in this ore. Approach: The natural radionuclides (238U, 232Th and 40K contents of Manganese ore samples collected by Siani Manganese Company in Egypt-Cairo have been determined by low background spectroscopy using hyper-pure germanium (HPGe detector. Results: The mean activities due to the three radionuclides (238U, 232Th and40K were found to be 3543±106, 222±6.6 and 3483±104 Bqkg-1, respectively. The absorbed dose rate due to the natural radioactivity in samples under investigation ranged from 1522±45-1796±53 nGyh-1. The radium equivalent activity varied from 3807±114-4446±133 Bqkg-1. The representative external hazard index values for the corresponding samples are also estimated. Conclusion: The results of this assessment obtained by the gamma-ray spectroscopic analysis, have indicated that the levels of natural radioactivity were higher than the international recommended limits.

  19. Mobility factors of cracked ore in vibrating-ore draw shafts

    Institute of Scientific and Technical Information of China (English)

    WU Ai-xiang; JIANG Li-chun; CHEN Jia-sheng

    2005-01-01

    The mobile factors of cracked ore in vibrating-ore draw shafts were analyzed. The results show that the mobile coefficient of cracked ores will be mainly influenced by the combination of ore physical factors if the structure dimension and parameters of vibrating ore-draw shafts are sure. It decreases with increasing the cohesion, lump content, lump size and powder content and increases with increasing the porosity. The coefficient decreases with increasing the moisture content, but increases after the moisture content reaches a certain value. Uniform grain leads to better mobility, non-uniform grain leads to worse mobility. The value of the mobile coefficient should be in a range of 0.31.1 when designing the vibrating ore-draw shafts. According to correlation degree of grey system theory, the effects of factors on the mobility of cracked ore are given in the weight decreasing consequence as follows: moisture content, lump content, distribution of grain size, lump size, porosity, cohesion and powder ore content. It is unreasonable to neglect any one because the values of their weights are not obvious.

  20. Contrasting REE Signatures on Manganese Ores of Iron Ore Group in North Orissa, India

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The distribution pattern of Rare Earth Elements (REE) in three categories of manganese ores viz.stratiform, stratabound-replacement, and detrital of Precambrian Iron Ore Group from north Orissa, India was reported.These categories of Mn-ore differed in their major and trace chemistry and exhibited contrasting REE signature.The stratiform ores were relatively enriched in REE content (697 μg·g-1) and their normalized pattern showed both positive Ce and Eu anomalies, whereas the stratabound-replacement types were comparatively depleted in REE content (211 μg·g-1) and showed negative Ce and flat Eu signatures.The detrital categories showed mixed REE pattern.The data plotted in different discrimination diagrams revealed a mixed volcaniclastic and chemogenic source of material for stratiform categories, and LREE (Light Rare Earth Elements) and HREE (Heavy Rare Earth Elements) are contributed by such sources, respectively.In contrast, the stratabound ore bodies were developed during the remobilization of stratiform ores, and associated Mn-containing rocks under supergene condition followed by the redeposition of circulating mineralized colloidal solutions in structurally favorable zones.During this process, some of the constituents were found only in very low concentration within stratabound ores, and this is attributed to their poor leachability/mobility.The detrital ores did not exhibit any significant characteristic in respect of REE as their development was via a complex combination of processes involving weathering, fragmentation, recementation, and burial under soil cover.

  1. Technical Report on the Behavior of Trace Elements, Stable Isotopes, and Radiogenic Isotopes During the Processing of Uranium Ore to Uranium Ore Concentrate

    Energy Technology Data Exchange (ETDEWEB)

    Marks, N. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Borg, L. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Eppich, G. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gaffney, A. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Genneti, V. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hutcheon, I. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kristo, M. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Lindvall, R. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ramon, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Robel, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Roberts, S. K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Schorzman, K. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sharp, M. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Singleton, M. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Williams, R. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-07-09

    The goals of this SP-1 effort were to understand how isotopic and elemental signatures behave during mining, milling, and concentration and to identify analytes that might preserve geologic signatures of the protolith ores. The impurities that are preserved through the concentration process could provide useful forensic signatures and perhaps prove diagnostic of sample origin.

  2. 熔融制样-波长色散X射线荧光光谱法测定红土镍矿中铁、镍、硅、铝、镁、钙、钛、锰、铜和磷%Determination of iron, nickel, silicon, aluminum, magnesium, calcium, titanium, manganese,copper and phosphorus in laterite nickel ores by wavelength dispersive X-ray fluorescence spectrometry with fusion sample preparation

    Institute of Scientific and Technical Information of China (English)

    林忠; 李卫刚; 褚宁; 蒋晓光; 孙涛; 林志伟; 王艳君

    2012-01-01

    A wavelength dispersive X - ray fluorescence spectrometry with fusion sample preparation has been developed for determination of iron, nickel, silicon, aluminum, magnesium, calcium, titanium, manganese, copper and phosphorus in laterite nickel ores. Calibration samples were prepared by adding high pure oxides and standard solutions of pending elements into iron ore standards, which were applied as matrix and ignited in 1000 ℃. The experimental conditions including of fluxing agent, fusion time, dilution ratios, doffing membrane reagent and matrix effects were determined. The analytical results were proposed by loss on ignition calibration, which were agreement with those obtained by wet method analysis, and the relative standard deviation was between 0. 219 % and 2. 817 %. The method was satisfied the request of laterite nickel ores test.%建立了熔融制样-波长色散X射线荧光光谱法测定红土镍矿中铁、镍、硅、铝、镁、钙、钛、锰、铜和磷含量的方法.采用经1000℃灼烧后的铁矿标准样品为基体,添加相关待测元素的高纯氧化物和标准溶液制作校准曲线用的校准样品,确定了助熔剂、熔融时间、稀释比、脱模剂和基体效应校正方式等试验条件.样品分析结果进行烧失量校正,与湿法分析结果的相对标准偏差介于0.219%~2.817%之间,满足红土镍矿检测需要.

  3. Sedimentary carbonate-hosted giant Bayan Obo REE-Fe-Nb ore deposit of Inner Mongolia, China; a cornerstone example for giant polymetallic ore deposits of hydrothermal origin

    Science.gov (United States)

    Chao, E.C.T.; Back, J.M.; Minkin, J.A.; Tatsumoto, M.; Junwen, Wang; Conrad, J.E.; McKee, E.H.; Zonglin, Hou; Qingrun, Meng; Shengguang, Huang

    1997-01-01

    on the ages of mineralization and the history of the deposit. Textural relations, differences in chemical composition, and 232Th/208Pb internal isochron ages of monazite and bastnaesite samples indicate that many episodes of REE mineralization occurred at Bayan Obo, ranging from about 555 Ma to about 398 Ma. Initial 208Pb/204Pb ratios suggest different sources of REE's for different generations of REE minerals. Relative ages of Fe mineralization were deduced from textural relationships of Fe minerals with other, dated mineral phases in the deposit. Most Nb mineralization was in the area of the West Orebodies and resulted in disseminated ore. Aeschynite, an early stage of Nb mineralization (438+-25.1 Ma), occurs with huanghoite and alkali amphiboles in veins. The 40Ar/39Ar ages of amphiboles, as well as petrographic textures, were used to distinguish three periods of regional metamorphism in the Bayan Obo mine area: (1) Late Proterozoic, about 890 Ma, which recrystallized H8 carbonate to marble and crystallized lineated alkali amphiboles along foliation planes in the marble; (2) Caledonian, about 425-395 Ma, which resulted in metamorphic and metasomatic-metamorphic alkali amphiboles; and (3) Hercynian, about 300 Ma, based on biotite 40Ar/39Ar analyses from biotite schist and folded banded ores. The 40Ar/39Ar ages of metasomatic alkali amphiboles also place time constraints on the hydrothermal history of the ore deposit. Metasomatic amphiboles represent periods of intense hydrothermal activity, which began as early as 1.26 Ga; that date is based on the age of amphibole from a vein that crosscuts the H6 quartzite that underlies the H8 dolostone marble. Although much of the metasomatic amphibole formed during periods that overlapped the peak period of REE mineralization of banded ores, REE and alkali amphibole phases generally occur in different mineral assemblages or are of very different ages in the same assemblage and, therefore, may have been derived from

  4. Speciation of arsenic in pyrite by micro-X-ray absorption fine- structure spectroscopy (XAFS)

    Energy Technology Data Exchange (ETDEWEB)

    Paktunc, D. (CCM)

    2008-09-30

    Pyrite (FeS2) often contains variable levels of arsenic, regardless of the environment of formation. Arsenian pyrite has been reported in coals, sediments and ore deposits. Arsenian pyrite having As concentrations of up to 10 wt % in sedimentary rocks (Kolker et al. 1997), about 10 wt% in gold deposits (Fleet et al. 1993), 12 wt % in a refractory gold ore (Paktunc et al. 2006) and 20 wt % in a Carlin-type gold deposit in Nevada (Reich et al. 2005) have been reported. Arsenian pyrite is the carrier of gold in hydrothermal Carlin-type gold deposits, and gold concentrations of up to 0.9 wt % have been reported (Reich et al. 2005; Paktunc et al. 2006). In general, high Au concentrations correlate with As-rich zones in pyrite (Paktunc et al. 2006). Pyrite often ends up in mining and metallurgical wastes as an unwanted mineral and consititutes one of the primary sources of As in the wastes. Arsenic can be readily released to the environment due to rapid oxidative dissolution of host pyrite under atmospheric conditions. Pyrite is also the primary source of arsenic in emissions and dust resulting from combustion of bituminous coals. Despite the importance of arsenian pyrite as a primary source of anthropogenic arsenic in the environment and its economic significance as the primary carrier of gold in Carlin-type gold deposits, our understanding of the nature of arsenic in pyrite is limited. There are few papers dealing with the mode of occurrence of arsenic by bulk XAFS in a limited number of pyrite-bearing samples. The present study documents the analysis of pyrite particles displaying different morphologies and a range of arsenic and gold concentrations to determine the nature and speciation of arsenic.

  5. Raman Spectroscopic Characterisation of Australian Banded Iron Formation and Iron Ore

    Science.gov (United States)

    Wells, M. A.; Ramanaidou, E. R.

    2012-04-01

    In Australia and world-wide over the past 5-10 years, declining reserves of premium, high-grade (>64% Fe), low-P bearing iron ore, have seen iron ore producers increase their utilisation of lower Fe-grade, higher P/Al/Si ore. In Australia, the channel iron deposits (CID), bedded iron deposits (BID) and, more recently, BIF-derived magnetite iron deposits (MID) have seen increased usage driven mainly by the increased demand from Chinese steel mills (Ramanaidou and Wells, 2011). Efficient exploitation and processing of these lower-grade iron ores requires a detailed understanding of their iron oxide and gangue mineralogy and geochemistry. The common Fe-bearing minerals (e.g., hematite, magnetite, goethite and kenomagnetite) in these deposits, as well as gangue minerals such as quartz and carbonates, are all strongly Raman active (e.g., de Faria et al., 1997). Their distinct Raman spectra enable them to be easily detected and mapped in situ in either unprepared material or samples prepared as polished blocks. In this paper, using representative examples of Australian CID ore, martite-goethite bedded iron deposit (BID) ore and banded iron formation (BIF) examined as polished blocks, we present a range of Raman spectra of the key iron ore minerals, and discuss how Raman spectroscopy can be applied to characterising iron ore mineralogy. Raman imaging micrographs, obtained using a StreamLine Plus Raman imaging system, clearly identified the main Fe-oxide and gangue components in the CID, BID and BIF samples when compared to optical micrographs. Raman analysis enabled the unequivocal identification of diamond in the CID ore as a contaminant from the polishing paste used to prepare the sample, and confirmed the presence of hematite in the BID ore in the form of martite, which can be morphologically similar to magnetite and, thus, difficult to otherwise distinguish. Image analysis of Raman mineral maps could be used to quantify mineral abundance based on the number of 'pixels

  6. AMS of natural {sup 236}U and {sup 239}Pu produced in uranium ores

    Energy Technology Data Exchange (ETDEWEB)

    Wilcken, K.M. [Department of Nuclear Physics, RSPhysSE, Australian National University, Canberra, ACT 0200 (Australia)]. E-mail: k.wilcken@suerc.gla.ac.uk; Barrows, T.T. [Department of Nuclear Physics, RSPhysSE, Australian National University, Canberra, ACT 0200 (Australia); Fifield, L.K. [Department of Nuclear Physics, RSPhysSE, Australian National University, Canberra, ACT 0200 (Australia); Tims, S.G. [Department of Nuclear Physics, RSPhysSE, Australian National University, Canberra, ACT 0200 (Australia); Steier, P. [VERA Laboratory, Institute for Isotopic Research and Nuclear Physics, University of Vienna, Waehringer Strasse 17, A-1090 Vienna (Austria)

    2007-06-15

    The rare isotopes {sup 236}U and {sup 239}Pu are produced naturally by neutron capture in uranium ores. Here we measure {sup 236}U and {sup 239}Pu by accelerator mass spectrometry (AMS) in the same ore samples for the first time. To ensure efficient extraction of both elements and isotopic equilibrium between the {sup 239}Pu in the ore and a {sup 242}Pu spike, we developed a new sample preparation protocol. AMS has clear advantages over previous methods because it achieves better discrimination against molecular interferences with higher sensitivity and shorter counting times. Measurements of {sup 236}U and {sup 239}Pu hold considerable promise as proxy indicators of neutron flux and uranium concentration.

  7. Selective Flocculation of Dilband Iron Ore, Pakistan

    Directory of Open Access Journals (Sweden)

    Muhammad Ishaque Abro

    2011-04-01

    Full Text Available Selective flocculation for long is known as one of the beneficiation techniques applicable to the concentration of finely disseminated ores. The success of this technique is based on the selective adsorption of an organic polymer on the mineral particles to be flocculated. In present study beneficiation of finely disseminated Dilband iron ore using selective flocculation has been attempted. The effect of pH, sodium silicate (Na2SiO3, sodium hexametaphosphate (Na2OP2O5, sodium trypolyphosphate (Na5P3O10, ethylediaminetretracetae (NaCH2-CH2N, flocculant doses, and flocculant mixing method on the selective adsorption of corn starch on hematite, the chief iron mineral, was studied comprehensively. Improvement in grade was assessed by XRF analysis of the flocculation products. The selective flocculation upgraded the ore from 52% hematite (i.e. 39% Fe to 60% hematite (i.e. 45% Fe with an average hematite recovery of 15%. Appreciable increase in ore grade with sufficiently poor recovery suggested that selective flocculation process is not adequate beneficiating technique to upgrade the Dilband iron ore due to heavily intergrowth of impurities.

  8. Numerical simulation of high voltage electric pulse comminution of phosphate ore

    Institute of Scientific and Technical Information of China (English)

    Razavian Seyed Mohammad; Rezai Bahram; Irannajad Mehdi; Ravanji Mohammad Hasan

    2015-01-01

    Numerical simulation of the electrical field distribution helps in-depth understanding of the mechanisms behind the responses and the benefits of the high voltage pulse comminution. The COMSOL Multiphysics package was used to numerically simulate the effect of ore compositions in this study. Regarding phos-phate ore particles shape and composition, the effects of mineral composition, particle size, particle shape and electrodes distance were investigated on the electrical field intensity and distribution. The results show that the induced electrical field is significantly dependent on the electrical properties of minerals, the feed particle size and the location of conductive minerals in ores. The angle of material contact sur-face with the discharge electrode is also an important factor in the intensity of electrical field. Moreover, it is found that the specific liberation effect at the disintegration of phosphate ore by electrical pulses is due to the locality of the electrical field at the interface of mineral components of the phosphate ore aggregates with different permittivities. However, the intensity of the electrical field increases with shar-pening the contact angle. Besides, the electrical discharge in the samples is converted to the elec-trohydraulic discharge across the surrounding water by changing the distance between the discharge electrode and sample surface.

  9. Multistage dilute acid leaching of a medium grade iron ore to super-concentrate

    Directory of Open Access Journals (Sweden)

    Adeleke A.A.

    2014-01-01

    Full Text Available The phosphorous laden Koton Karfe iron ore is a medium grade iron ore deposit in Nigeria that can be upgraded as a super-concentrate for use at the Aladja Steel Midrex plant. The 75 μm size sample fraction of the ore was preconcentrated with shaking table and leached in the oven at atmospheric pressure with dilute hydrochloric acid in single and multistage leaching sequences of H2O-HCl-H2O and HCl-H2O-H2O. The as-received, as-tabled and asleached samples were then subjected to X-ray fluorescence and microscopic analyses. The results obtained showed that the H2O-HCl-H2O route produced a higher grade concentrate that assayed 68.54% Fe indicating about 58% upgrade in iron content; while the phosphorus and sulphur contents were reduced by about 77 and 99.6% respectively. In addition, the silicon, manganese, and titanium contents were drastically reduced, while potassium was completely eliminated. The upgrade of iron content in the ore to 68.54% and the drastic reduction in phosphorous and sulphur contents has thus rendered the Koton Karfe iron ore suitable for use as a super concentrate for the Aladja steel plant direct reduction iron making process.

  10. Natural radioactivities in iron and nickel ores imported into Japan and the dose assessment for workers handling them.

    Science.gov (United States)

    Iwaoka, Kazuki; Tagami, Keiko; Yonehara, Hidenori

    2010-09-01

    Japan imports Fe and Ni ores from abroad for use as industrial raw materials in the manufacture of industrial products like stainless steel. Some of these ores might contain high levels of radioactivity, and then workers handling them would be exposed to radiation without being aware of it. Activity concentrations in these ores should be measured to evaluate the radiation exposure of workers. In this study, Fe and Ni ores used as industrial raw materials were collected from iron and steel companies, and the activity concentrations of the (238)U series, the (232)Th series and (40)K in these ores were determined using inductively coupled plasma mass spectrometry (ICP-MS) and gamma ray spectrometry. The activity concentrations of the (238)U series, the (232)Th series and (40)K in these ores samples were lower than the International Atomic Energy Agency (IAEA) values. The doses to workers handling these ores were estimated using methods for dose assessment given in a report by the European Commission. In each scenario, a maximum value of the annual effective dose to workers was estimated to be about 6.8 × 10(-6) Sv, which was lower than intervention exemption levels (annual dose 1.0 × 10(-3) Sv) given in International Commission on Radiological Protection (ICRP) Publication 82.

  11. Natural radioactivities in iron and nickel ores imported into Japan and the dose assessment for workers handling them

    Energy Technology Data Exchange (ETDEWEB)

    Iwaoka, Kazuki; Tagami, Keiko; Yonehara, Hidenori, E-mail: iwaoka@nirs.go.j [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan)

    2010-09-15

    Japan imports Fe and Ni ores from abroad for use as industrial raw materials in the manufacture of industrial products like stainless steel. Some of these ores might contain high levels of radioactivity, and then workers handling them would be exposed to radiation without being aware of it. Activity concentrations in these ores should be measured to evaluate the radiation exposure of workers. In this study, Fe and Ni ores used as industrial raw materials were collected from iron and steel companies, and the activity concentrations of the {sup 238}U series, the {sup 232}Th series and {sup 40}K in these ores were determined using inductively coupled plasma mass spectrometry (ICP-MS) and gamma ray spectrometry. The activity concentrations of the {sup 238}U series, the {sup 232}Th series and {sup 40}K in these ores samples were lower than the International Atomic Energy Agency (IAEA) values. The doses to workers handling these ores were estimated using methods for dose assessment given in a report by the European Commission. In each scenario, a maximum value of the annual effective dose to workers was estimated to be about 6.8 x 10{sup -6} Sv, which was lower than intervention exemption levels (annual dose 1.0 x 10{sup -3} Sv) given in International Commission on Radiological Protection (ICRP) Publication 82. (note)

  12. Mercury isotope fractionation during ore retorting in the Almadén mining district, Spain

    Science.gov (United States)

    Gray, John E.; Pribil, Michael J.; Higueras, Pablo L.

    2013-01-01

    Almadén, Spain, is the world's largest mercury (Hg) mining district, which has produced over 250,000 metric tons of Hg representing about 30% of the historical Hg produced worldwide. The objective of this study was to measure Hg isotopic compositions of cinnabar ore, mine waste calcine (retorted ore), elemental Hg (Hg0(L)), and elemental Hg gas (Hg0(g)), to evaluate potential Hg isotopic fractionation. Almadén cinnabar ore δ202Hg varied from − 0.92 to 0.15‰ (mean of − 0.56‰, σ = 0.35‰, n = 7), whereas calcine was isotopically heavier and δ202Hg ranged from − 0.03‰ to 1.01‰ (mean of 0.43‰, σ = 0.44‰, n = 8). The average δ202Hg enrichment of 0.99‰ between cinnabar ore and calcines generated during ore retorting indicated Hg isotopic mass dependent fractionation (MDF). Mass independent fractionation (MIF) was not observed in any of the samples in this study. Laboratory retorting experiments of cinnabar also were carried out to evaluate Hg isotopic fractionation of products generated during retorting such as calcine, Hg0(L), and Hg0(g). Calcine and Hg0(L) generated during these retorting experiments showed an enrichment in δ202Hg of as much as 1.90‰ and 0.67‰, respectively, compared to the original cinnabar ore. The δ202Hg for Hg0(g) generated during the retorting experiments was as much as 1.16‰ isotopically lighter compared to cinnabar, thus, when cinnabar ore was roasted, the resultant calcines formed were isotopically heavier, whereas the Hg0(g) generated was isotopically lighter in Hg isotopes.

  13. The physical hydrogeology of ore deposits

    Science.gov (United States)

    Ingebritsen, Steven E.; Appold, M.S.

    2012-01-01

    Hydrothermal ore deposits represent a convergence of fluid flow, thermal energy, and solute flux that is hydrogeologically unusual. From the hydrogeologic perspective, hydrothermal ore deposition represents a complex coupled-flow problem—sufficiently complex that physically rigorous description of the coupled thermal (T), hydraulic (H), mechanical (M), and chemical (C) processes (THMC modeling) continues to challenge our computational ability. Though research into these coupled behaviors has found only a limited subset to be quantitatively tractable, it has yielded valuable insights into the workings of hydrothermal systems in a wide range of geologic environments including sedimentary, metamorphic, and magmatic. Examples of these insights include the quantification of likely driving mechanisms, rates and paths of fluid flow, ore-mineral precipitation mechanisms, longevity of hydrothermal systems, mechanisms by which hydrothermal fluids acquire their temperature and composition, and the controlling influence of permeability and other rock properties on hydrothermal fluid behavior. In this communication we review some of the fundamental theory needed to characterize the physical hydrogeology of hydrothermal systems and discuss how this theory has been applied in studies of Mississippi Valley-type, tabular uranium, porphyry, epithermal, and mid-ocean ridge ore-forming systems. A key limitation in the computational state-of-the-art is the inability to describe fluid flow and transport fully in the many ore systems that show evidence of repeated shear or tensional failure with associated dynamic variations in permeability. However, we discuss global-scale compilations that suggest some numerical constraints on both mean and dynamically enhanced crustal permeability. Principles of physical hydrogeology can be powerful tools for investigating hydrothermal ore formation and are becoming increasingly accessible with ongoing advances in modeling software.

  14. Sandbox experiments on Uraninite Ore: ERT and SP measurments.

    Science.gov (United States)

    Singh, R. K.

    2015-12-01

    Nuclear energy, considering its own intrinsic merits, would be a leading source for meeting the energy requirement in present and future scenario. Concealed Uranium deposits under sedimentary cover, with poor surface indications calls for reorientation of survey with large inputs involving integrated geophysical approach. Sand Box experiments have been carried out over Uraninite ore. The tank is a glass fish tank (height 39 cm, length 75 cm, width 30 cm). It was filled with sand up to 35 cm high. The sand was saturated from below to minimize the entrapment of the gas bubbles. The average size for sand grains is ~ 0.295mm. The formation factor of the sand is 3.5, with a negligible surface conductivity because of the coarse nature of the sand grains. The dimension of considered Uraninite ore sample is 4cm x 4cm x 4cm. The depth of top of the ore sample is kept at 3cm. In this paper both resistivity and self-potential measurements were carried out for possible detection of Uraninite. The resistivity measurements were made with 64 non-polarizable electrodes using Electrical Resistivity Tomography (ERT) equipment of FlashRes Universal developed by ZZ Resistivity Imaging Pty. Ltd. We have used screws of length 3cm as electrodes. The separation between these electrodes are ~ 1cm. The resistivity tomography results clearly outlines the target Uraninite body. The resistivity tomography results also detects small heterogeneities associated with air bubbles possibly due to unsaturated pore spaces. SP measurements were made using two non-polarizing Pb/PbCl2 electrodes and a Fluke 289 voltmeter (sensitivity 0.001 mV, internal impedance 100 MOhm). The reference electrode was located on the corner of the sandbox. The other electrode was used to scan the electrical potential at the surface of the sand. SP measurements were made with a spacing of 3 cm over the same ERT profile. The SP results also shows a dip (or a low SP anomaly) over the target ore body sample. Thus, both SP and

  15. A new radiation shielding material: Amethyst ore

    Energy Technology Data Exchange (ETDEWEB)

    Korkut, Turgay, E-mail: turgaykorkut@hotmail.co [Faculty of Science and Art, Department of Physics, Ibrahim Cecen University, Agri (Turkey); Korkut, Hatun [Faculty of Science and Art, Department of Physics, Ibrahim Cecen University, Agri (Turkey); Karabulut, Abdulhalik; Budak, Goekhan [Faculty of Science, Department of Physics, Atatuerk University, Erzurum (Turkey)

    2011-01-15

    This paper describes a new radiation shielding material, amethyst ore. We have determined the elemental composition of amethyst using WDXRF spectroscopy technique. To see the shielding capability of amethyst for several photon energies, these results have been used in simulation process by FLUKA Monte Carlo radiation transport code. Linear attenuation coefficients have been calculated according to the simulation results. Then, these values have been compared to a fine shielding concrete material. The results show that amethyst shields more gamma beams than concrete. This investigation is the first study about the radiation shielding properties of amethyst ore.

  16. METALLOGENIC SYSTEM OF DACHANG TINPOLYMETALLIC ORE FIELD

    Institute of Scientific and Technical Information of China (English)

    WU Xiang-bin; DAI Ta-gen; WANG Zhi-bin; FANG Sheng-kui

    2001-01-01

    The Dachang tin-polymetallic ore field in northern Guangxi,China,lies in a mid-late Paleozoic rift that borders up the southern boundary of the Jiangnan-Xuefeng Massif.As a giant ore deposit,it deposited in middle of the Nandang-Hechi metallogenic zone.The orehosting strata are of the Devonion,which shows the evident characteristics of polymetallic elements,i.e: ,Sn,Zn,Pb,Sb,As,Cu,Ag,In,Ge,Cd,et al.,and over 1 000 000 t tin reserves.

  17. Partitioning properties of rare earth ores in China

    Institute of Scientific and Technical Information of China (English)

    CHI Ru'an; LI Zhongjun; PENG Cui; ZHU Guocai; XU Shengming

    2005-01-01

    The properties of rare earth partitioning in Chinese industrial rare earth ores were analyzed. Rare earth ores can be divided into the single-mineral type ore with bastnaesite, the multi-mineral type ore with bastnaesite and monazite, and the weathering crust type. Both the Bayan Obo rare earth ore and the Zhushan rare earth ore are a kind of mixed ore, consisting of bastnaesite and monazite. Their rare earth partitionings are strongly enriched in light rare earths, where CeO2 is 50% and the light rare earth partitioning is totally over 95%. The Mianning rare earth ore as well as the Weishan rare earth is a kind of rare earth ore only having bastnaesite. Their rare earth partitionings are also strongly enriched in light rare earths,in which CeO2 is 47% and the light rare earth partitioning is totally over 94%. For the weathering crust type rare earth ore,there are the Longnan rare earth ore, the Xunwu rare earth ore, and the middle yttrium and rich europium ore. In the Longnan rare earth ore, which is strongly enriched in heavy rare earths, Y2O3 is 64.83%, and the heavy and light rare earth partitionings are 89.40% and 10.53%, respectively. In the Xunwu rare earth ore, which is strongly enriched in light rare earths, CeO2 is 47.16%, and the light rare earth partitioning is totally 93.25%. Y and Eu are enriched in the middle yttrium and rich europium ore. Its middle rare earth partitioning is totally over 10%, and Eu2O3 and Y2O3 are over 0.5% and 20%,respectively, which are mainly industrial resources of the middle and the heavy rare earths.

  18. Rare Earth Elements Geochemistry of Laowan Gold Deposit in Henan Province: Trace to Source of Ore-Forming Materials

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The compositions of REE in quartz and pyrite from the main stage of the Laowan gold deposit in Henan Province and that in quartz from Laowan granite were determined by inductively coupled plasma-mass-spectrometry (ICP-MS) to trace the source of ore-forming materials. Meanwhile, the REE compositions of the deposit ore, granite and metamorphic wall rock were also considered for comparative studies in detail. The range of ∑REE of quartz and pyrite from the deposit ores is 4.18×10-6~30.91×10-6, the average of ∑REE is 13.39×10-6, and the average of ∑REE of quartz in the Laowan granite is 6.68×10-6. There is no distinct difference of REE parameters between the deposit ore quartz and granite quartz. The quartz in gold deposit has the same REE particular parameters as quartzes from Laowan granite, such as δEu, δCe, (La/Yb)N and (La/Sm)N, partition degree of LREE to HREE, especially, the chondrite-normalized REE patterns, but no similarity to those from metamorphic wall rock, which shows that ore-forming hydrothermal fluid is mainly the fluid coming from the Laowan granite magma, rather than metamorphic fluid. Meanwhile, comparison studies on REE features between minerals from the deposit ores and related geological bodies in the deposit show that REE characteristics of minerals can serve as an indicator of ore-forming fluid properties and sources, while the REE characteristics of the bulk samples (such as deposit ores, granites and wall rocks) can not trace the source of the ore-forming materials exactly.

  19. Application of lead and strontium isotope ratio measurements for the origin assessment of uranium ore concentrates.

    Science.gov (United States)

    Varga, Zsolt; Wallenius, Maria; Mayer, Klaus; Keegan, Elizabeth; Millet, Sylvain

    2009-10-15

    Lead and strontium isotope ratios were used for the origin assessment of uranium ore concentrates (yellow cakes) for nuclear forensic purposes. A simple and low-background sample preparation method was developed for the simultaneous separation of the analytes followed by the measurement of the isotope ratios by multicollector inductively coupled plasma mass spectrometry (MC-ICPMS). The lead isotopic composition of the ore concentrates suggests applicability for the verification of the source of the nuclear material and by the use of the radiogenic (207)Pb/(206)Pb ratio the age of the raw ore material can be calculated. However, during data interpretation, the relatively high variation of the lead isotopic composition within the mine site and the generally high contribution of natural lead as technological contamination have to be carefully taken into account. The (87)Sr/(86)Sr isotope ratio is less prone to the variation within one mine site and less affected by the production process, thus it was found to be a more purposeful indicator for the origin assessment and source verification than the lead. The lead and strontium isotope ratios measured and the methodology developed provide information on the initial raw uranium ore used, and thus they can be used for source attribution of the uranium ore concentrates.

  20. (234)U/(238)U signatures associated with uranium ore bodies: part 2 Manyingee.

    Science.gov (United States)

    Lowson, Richard T; McIntyre, Mark G

    2013-04-01

    The Manyingee ore body is a roll-front U ore body located at depth in the Cretaceous sandstone sediments of a Proterozoic palaeo valley. It is located in a confined aquifer. The aquifer is recharged 4 km upstream by the Ashburton River. Groundwater samples were collected at and up to 4.7 km downstream of the ore body. The ground water (234)U/(238)U activity ratios (AR) were elevated to 1.86 in the vicinity of the ore body and then declined to 1.06 over the 4.7 km transect. The elevated (234)U/(238)U ARs are attributed to selective leaching of (234)U sites by oxidising waters, with α recoil as a necessary precursor to produce activated (234)U sites. Direct ejection into another phase following α recoil is considered to be a minor contributor to (234)U -(238)U disequilibrium in this environment. The profile is considered to be typical of the (234)U/(238)U AR profile at and down gradient of the redox front of a U ore body.

  1. Sintering Properties and Optimal Blending Schemes of Iron Ores

    Institute of Scientific and Technical Information of China (English)

    Dauter0liveira; WUSheng—li; DAIYu—ming; XUJian; CHEN Hong

    2012-01-01

    In order to obtain good sintering performance, it is important to understand sintering properties of iron ores. Sintering properties including chemical composition, granulation and high-temperature behaviors of ores from China, Brazil and Australia. Furthermore, several indices were defined to evaluate sintering properties of iron ores. The results show that: for chemical composition, Brazilian ores present high TFe, low SiOz, and low Alz03 con- tent. For granulation, particle diameter ratio of Brazilian ores are high; particle intermediate fraction of Chinese con- centrates are low; and average particle size and clay type index of Australian ores are high. For high-temperature properties, ores from China, Brazil and Australia present different characteristics. Ores from different origins should be mixed together to obtain good high-temperature properties. According to the analysis of each ore's sintering prop- erties, an ore blending scheme (Chinese concentrates 20 ~-1- Brazilian ores 400//oo -k Australian ores 40 ~) was sugges- ted. Moreover, sinter pot test using blending mix was performed, and the results indicated that the ore blending scheme led to good sintering performance and sinter quality.

  2. 熔融制样-波长色散X射线荧光光谱法测定镍矿石中主次量元素%Determination of major/minor elements in nickel ore based on fusion sample preparation-wavelength dispersive X-ray fluorescence spectrometry method

    Institute of Scientific and Technical Information of China (English)

    刘向东; 张凯歌; 孙杨

    2016-01-01

    Fusion sample preparation is used to eliminate influence of matrix effect on the analysis results ,and ammonium nitrate as oxidant to eliminate corrosion of sample on melting pot .The basic parameter method NBSGSC is applied to get the theoretical alphas coefficient ,and the standard curve is corrected with concentration multiply mode with L .O .I correction factor .The relative coefficients between the groups is in the range of 0 .998 2~ 0 .999 9 ,the standard deviation (RSD , n= 11) is between 4 0.2% and 0 3.9% .The method is suitable for the measurement of major /minor elements in nickel ores .%采用熔融制样消除基体效应对分析结果的影响,硝酸铵作为氧化剂以消除试样对坩埚的腐蚀。应用基本参数法NBSGSC得到理论alphas系数,结合L .O I.计算理论的元素间校正因子,基于浓度的乘法模式对标准曲线进行校正。各组标准曲线的相关系数在09.982~09.999之间,相对标准偏差(RSD ,n=11)在03.9%~40.2%之间。该方法适用于镍矿石主次量元素的检测。

  3. Influence of flotation cell volume and solids mass on kinetics of sulfide ore flotation

    OpenAIRE

    Plawski Michal; Bakalarz Alicja

    2016-01-01

    The paper presents studies on the influence of flotation cell capacity and mass of solids in the suspension on the flotation kinetics of sulfide copper ore. A sample of copper ore that was collected from the Polkowice Mine of KGHM Polska Miedz S.A. in Poland was used in the experiments. It was determined that neither the volume of flotation cell nor the mass of solids had influence on the type of kinetics equation of flotation. Copper-bearing minerals floated according to the second-order equ...

  4. Analytical fingerprint for tantalum ores from African deposits

    Science.gov (United States)

    Melcher, F.; Graupner, T.; Sitnikova, M.; Oberthür, T.; Henjes-Kunst, F.; Gäbler, E.; Rantitsch, G.

    2009-04-01

    Illegal mining of gold, diamonds, copper, cobalt and, in the last decade, "coltan" has fuelled ongoing armed conflicts and civil war in a number of African countries. Following the United Nations initiative to fingerprint the origin of conflict materials and to develop a traceability system, our working group is investigating "coltan" (i.e. columbite-tantalite) mineralization especially in Africa, also within the wider framework of establishing certified trading chains (CTC). Special attention is directed towards samples from the main Ta-Nb-Sn provinces in Africa: DR Congo, Rwanda, Mozambique, Ethiopia, Egypt and Namibia. The following factors are taken into consideration in a methodological approach capable of distinguishing the origin of tantalum ores and concentrates with the utmost probability: (1) Quality and composition of coltan concentrates vary considerably. (2) Mineralogical and chemical compositions of Ta-Nb ores are extremely complex due to the wide range of the columbite-tantalite solid solution series and its ability to incorporate many additional elements. (3) Coltan concentrates may contain a number of other tantalum-bearing minerals besides columbite-tantalite. In our approach, coltan concentrates are analyzed in a step-by-step mode. State-of-the-art analytical tools employed are automated scanning electron microscopy (Mineral Liberation Analysis; MLA), electron microprobe analysis (major and trace elements), laser ablation-ICP-MS (trace elements, isotopes), and TIMS (U-Pb dating). Mineral assemblages in the ore concentrates, major and trace element concentration patterns, and zoning characteristics in the different pegmatites from Africa distinctly differ from each other. Chondrite-normalized REE distribution patterns vary significantly between columbite, tantalite, and microlite, and also relative to major element compositions of columbites. Some locations are characterized by low REE concentrations, others are highly enriched. Samples with

  5. Laser-induced breakdown spectroscopy measurements of uranium and thorium powders and uranium ore

    Energy Technology Data Exchange (ETDEWEB)

    Judge, Elizabeth J. [Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Barefield, James E., E-mail: jbarefield@lanl.gov [Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Berg, John M. [Manufacturing Engineering and Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Clegg, Samuel M.; Havrilla, George J.; Montoya, Velma M.; Le, Loan A.; Lopez, Leon N. [Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2013-05-01

    Laser-induced breakdown spectroscopy (LIBS) was used to analyze depleted uranium and thorium oxide powders and uranium ore as a potential rapid in situ analysis technique in nuclear production facilities, environmental sampling, and in-field forensic applications. Material such as pressed pellets and metals, has been extensively studied using LIBS due to the high density of the material and more stable laser-induced plasma formation. Powders, on the other hand, are difficult to analyze using LIBS since ejection and removal of the powder occur in the laser interaction region. The capability of analyzing powders is important in allowing for rapid analysis of suspicious materials, environmental samples, or trace contamination on surfaces since it most closely represents field samples (soil, small particles, debris etc.). The rapid, in situ analysis of samples, including nuclear materials, also reduces costs in sample collection, transportation, sample preparation, and analysis time. Here we demonstrate the detection of actinides in oxide powders and within a uranium ore sample as both pressed pellets and powders on carbon adhesive discs for spectral comparison. The acquired LIBS spectra for both forms of the samples differ in overall intensity but yield a similar distribution of atomic emission spectral lines. - Highlights: • LIBS analysis of mixed actinide samples: depleted uranium oxide and thorium oxide • LIBS analysis of actinide samples in powder form on carbon adhesive discs • Detection of uranium in a complex matrix (uranium ore) as a precursor to analyzing uranium in environmental samples.

  6. HANDLING, STORAGE AND IRON ORE QUALITY

    Directory of Open Access Journals (Sweden)

    Fabiana Fonseca Fortes

    2012-06-01

    Full Text Available This paper aims to identify handling and storage impact in iron ore quality, in their physical and chemical characteristics most important for a mining. It is tried to show the interferences in iron ore quality caused by the handling equipment and stockpiling. The research is restricted to Complexo Vargem Grande (Vale. The timeline was demarcated based on the formation of stockpiling. The fieldwork enables data collection and distinction of the routine procedures of casual operations handling. The quantitative analysis is conducted by the statistical method. As a conclusion, handling and storage identified are able to insert changes in physical and chemical characteristics of iron ore. Storage contributes to reduce variability of silica and alumina concentrations, but contributes too particle size deterioration. The handling induces degradation and segregation. However, there is the possibility to decrease handling of the ore and to establish the ideal size of stocks on the system in study, improving the efficiency of the system and consequent in global costs.

  7. Sources of ores of the ferroalloy metals

    Science.gov (United States)

    Burchard, E.F.

    1933-01-01

    Since all steel is made with the addition of alloying elements, the record of the metallic raw materials contributory to the steel industry would be far from complete without reference to the ferroalloy metals. This paper, therefore, supplements two preceding arvicles on the sources of our iron ores. The photographs, with the exception of those relating to molybdenum and vanadium, are by the author.

  8. In Situ Synchrotron Powder Diffraction Studies of Reduction-Oxidation (Redox) Behavior of Iron Ores and Ilmenite

    Science.gov (United States)

    Ilyushechkin, Alexander Y.; Kochanek, Mark; Tang, Liangguang; Lim, Seng

    2017-04-01

    Phase transformations of two types of iron-based oxides (iron ore and industrial-grade ilmenite) were studied using synchrotron powder diffraction of the samples processed in reducing and oxidizing atmospheres at 1173 K (900 °C) and 1223 K (950 °C), respectively. In iron ore oxidation, the disappearance of the wustite and fayalite phases was followed by hematite growth and a decrease of the magnetite phase. The magnetite phase was partially recovered by treatment in a reducing atmosphere. Ilmenite oxidation initiated decomposition of the ilmenite phase with rapid growth of hematite and gradual growth of the pseudobrookite phase. In a reducing atmosphere, ilmenite was gradually recovered from pseudobrookite with a relatively fast initial decrease in rutile and hematite content. Under reducing conditions, there was interaction of iron ore with magnesio-ferrites in iron ore-ash mixture and interaction of ilmenite with silica by the formation of fayalite.

  9. In Situ Synchrotron Powder Diffraction Studies of Reduction-Oxidation (Redox) Behavior of Iron Ores and Ilmenite

    Science.gov (United States)

    Ilyushechkin, Alexander Y.; Kochanek, Mark; Tang, Liangguang; Lim, Seng

    2017-01-01

    Phase transformations of two types of iron-based oxides (iron ore and industrial-grade ilmenite) were studied using synchrotron powder diffraction of the samples processed in reducing and oxidizing atmospheres at 1173 K (900 °C) and 1223 K (950 °C), respectively. In iron ore oxidation, the disappearance of the wustite and fayalite phases was followed by hematite growth and a decrease of the magnetite phase. The magnetite phase was partially recovered by treatment in a reducing atmosphere. Ilmenite oxidation initiated decomposition of the ilmenite phase with rapid growth of hematite and gradual growth of the pseudobrookite phase. In a reducing atmosphere, ilmenite was gradually recovered from pseudobrookite with a relatively fast initial decrease in rutile and hematite content. Under reducing conditions, there was interaction of iron ore with magnesio-ferrites in iron ore-ash mixture and interaction of ilmenite with silica by the formation of fayalite.

  10. Mining and processing of uranium ores at the Streltsovsky ore field

    Energy Technology Data Exchange (ETDEWEB)

    Ovseytchuk, V.A.; Litvinenko, V.G.; Kultishev, V.I. [Joint Stock Company, Priargunsky Industrial Mining and Chemical Union, Krasnokamensk, Chita Region (Russian Federation)

    2000-07-01

    The uranium deposits of Streltsovsky ore fields provide raw materials for Russian nuclear industry. For this region, it is important to achieve continued and increased activities in the recovery of mineral resources of uranium. Similarly, maintaining the mining and processing of uranium ores ensures the supply of raw materials for the nuclear industry. With the current operations, increasing the mining and processing activities would increase the cost of production of uranium oxides due to decreasing grades of ore body. After a review of the existing economic, technological and natural factors, a solution was proposed based on the joint application of underground mining and ore enrichment and processing with the help of hydrometallurgical process, in-situ leaching. Reduction of operation coasts and creation of radiation-safe working conditions could be achieved with the application of these systems involving concrete hardening in the mines and in-situ leaching of ore. With the help of economic-mathematical modeling, methods for rational application of various technologies could be determined and their processing parameters were specified. A reduction of coasts could be obtained and favorable conditions could be established for improvement in the treatment of lower grade ores by heap leaching. Application of purification of mine waters and tailing pond reduces the influence of the radiation and the impact on the natural environment. (author)

  11. Hydrogen Reduction of Hematite Ore Fines to Magnetite Ore Fines at Low Temperatures

    Directory of Open Access Journals (Sweden)

    Wenguang Du

    2017-01-01

    Full Text Available Surplus coke oven gases (COGs and low grade hematite ores are abundant in Shanxi, China. Our group proposes a new process that could simultaneously enrich CH4 from COG and produce separated magnetite from low grade hematite. In this work, low-temperature hydrogen reduction of hematite ore fines was performed in a fixed-bed reactor with a stirring apparatus, and a laboratory Davis magnetic tube was used for the magnetic separation of the resulting magnetite ore fines. The properties of the raw hematite ore, reduced products, and magnetic concentrate were analyzed and characterized by a chemical analysis method, X-ray diffraction, optical microscopy, and scanning electron microscopy. The experimental results indicated that, at temperatures lower than 400°C, the rate of reduction of the hematite ore fines was controlled by the interfacial reaction on the core surface. However, at temperatures higher than 450°C, the reaction was controlled by product layer diffusion. With increasing reduction temperature, the average utilization of hydrogen initially increased and tended to a constant value thereafter. The conversion of Fe2O3 in the hematite ore played an important role in the total iron recovery and grade of the concentrate. The grade of the concentrate decreased, whereas the total iron recovery increased with the increasing Fe2O3 conversion.

  12. Hydrogen Plasma Processing of Iron Ore

    Science.gov (United States)

    Sabat, Kali Charan; Murphy, Anthony B.

    2017-06-01

    Iron is currently produced by carbothermic reduction of oxide ores. This is a multiple-stage process that requires large-scale equipment and high capital investment, and produces large amounts of CO2. An alternative to carbothermic reduction is reduction using a hydrogen plasma, which comprises vibrationally excited molecular, atomic, and ionic states of hydrogen, all of which can reduce iron oxides, even at low temperatures. Besides the thermodynamic and kinetic advantages of a hydrogen plasma, the byproduct of the reaction is water, which does not pose any environmental problems. A review of the theory and practice of iron ore reduction using a hydrogen plasma is presented. The thermodynamic and kinetic aspects are considered, with molecular, atomic and ionic hydrogen considered separately. The importance of vibrationally excited hydrogen molecules in overcoming the activation energy barriers, and in transferring energy to the iron oxide, is emphasized. Both thermal and nonthermal plasmas are considered. The thermophysical properties of hydrogen and argon-hydrogen plasmas are discussed, and their influence on the constriction and flow in the of arc plasmas is considered. The published R&D on hydrogen plasma reduction of iron oxide is reviewed, with both the reduction of molten iron ore and in-flight reduction of iron ore particles being considered. Finally, the technical and economic feasibility of the process are discussed. It is shown that hydrogen plasma processing requires less energy than carbothermic reduction, mainly because pelletization, sintering, and cokemaking are not required. Moreover, the formation of the greenhouse gas CO2 as a byproduct is avoided. In-flight reduction has the potential for a throughput at least equivalent to the blast furnace process. It is concluded that hydrogen plasma reduction of iron ore is a potentially attractive alternative to standard methods.

  13. Hydrogen Plasma Processing of Iron Ore

    Science.gov (United States)

    Sabat, Kali Charan; Murphy, Anthony B.

    2017-03-01

    Iron is currently produced by carbothermic reduction of oxide ores. This is a multiple-stage process that requires large-scale equipment and high capital investment, and produces large amounts of CO2. An alternative to carbothermic reduction is reduction using a hydrogen plasma, which comprises vibrationally excited molecular, atomic, and ionic states of hydrogen, all of which can reduce iron oxides, even at low temperatures. Besides the thermodynamic and kinetic advantages of a hydrogen plasma, the byproduct of the reaction is water, which does not pose any environmental problems. A review of the theory and practice of iron ore reduction using a hydrogen plasma is presented. The thermodynamic and kinetic aspects are considered, with molecular, atomic and ionic hydrogen considered separately. The importance of vibrationally excited hydrogen molecules in overcoming the activation energy barriers, and in transferring energy to the iron oxide, is emphasized. Both thermal and nonthermal plasmas are considered. The thermophysical properties of hydrogen and argon-hydrogen plasmas are discussed, and their influence on the constriction and flow in the of arc plasmas is considered. The published R&D on hydrogen plasma reduction of iron oxide is reviewed, with both the reduction of molten iron ore and in-flight reduction of iron ore particles being considered. Finally, the technical and economic feasibility of the process are discussed. It is shown that hydrogen plasma processing requires less energy than carbothermic reduction, mainly because pelletization, sintering, and cokemaking are not required. Moreover, the formation of the greenhouse gas CO2 as a byproduct is avoided. In-flight reduction has the potential for a throughput at least equivalent to the blast furnace process. It is concluded that hydrogen plasma reduction of iron ore is a potentially attractive alternative to standard methods.

  14. REE Geochemistry of Sulfides from the Huize Zn-Pb Ore Field, Yunnan Province: Implication for the Sources of Ore-forming Metals

    Institute of Scientific and Technical Information of China (English)

    LI Wenbo; HUANG Zhilong; QI Liang

    2007-01-01

    REE abundances in sulfides from the Huize Zn-Pb ore field were determined with the ICPMS after preconcentration. The REE abundances in 26 sulfide samples (including pyrite, galena and sphalerite) are very low, with the ΣREE ranging from 1.6×10-9 to 166.8×10-9. Their LREE/HREE ratios range from 7.6 to 98, showing LREE enrichment relatively. The δEu values are below 1, indicating that they were deposited from an Eu-depleted and reducing fluid-system. Similar to the ore-hosting carbonate strata, calcite separates from carbonate veinlets filling in the fractures or faults crosscutting the carbonate strata also show clear Eu-depletion. This indicates that the carbonate veinlets and their parent fluid was possibly sourced from the strata and inherited the REE geochemical features of the strata. Therefore, REE-geochemical characteristics of both the sulfides and calcites, which were deposited from an ore-forming hydrothermal system, are similar to those of carbonate strata, and strongly suggest that the ore metals were mainly sourced from carbonate strata.

  15. Seeking the mantle contribution for the formation of giant ore deposits: Contemporaneous alkaline lamproites and carbonatites in the Kalmakyr and Muruntau ore districts, Tienshan, Uzbekistan

    Science.gov (United States)

    Seltmann, Reimar; Choulet, Flavien

    2014-05-01

    The decline in discoveries of ore deposits contrasted by the rising demand for e-tech metals requires the global mining industry to continuously seek innovation in exploration. Unravelling the source of metals is among the crucial questions in exploration targeting and geologists have often had to recourse to indirect determinations based on the nature of the magma conveying the metals. The relative contributions of mantle and crust in metallogenic processes and the origin of the magmas from either shallow or deep mantle are not fully understood in the current models of ore genesis. To help to resolve this dilemma, research must establish the link between anorogenic (within-plate) and orogenic processes by using a holistic approach featuring crustal processes, mantle dynamics and crust-mantle interactions that may contribute to the magma fertilization. To achieve this, our study focuses on indicators for the involvement of deep-mantle intrusions (lamproites, lamprophyres, etc.), which have the potential to encapsulate pristine samples of the mantle (xenoliths) during magma ascent [1,2]. The Tienshan belt hosting many giant ore deposits is quite exemplary for understanding mantle-crust interactions and identifying the nature of mantle contribution to ore systems. Sr-Nd-Hf-Pb isotope systematics on granitoids [3] showed a variation of crustal to mixed signatures, indicating involvement of both older crustal sources and mantle-derived material, but the mantle source is not clearly assessed. As objects for our case study in Uzbekistan we choose the Kalmakyr Cu-Au porphyry deposit (~ 315 Ma; Chatkal-Kurama continental arc of Middle Tienshan) and the Muruntau orogenic Au deposit (~290 Ma, Turkestan-Alai / Kyzylkum accretionary complex of South Tienshan) to investigate the impact of associated alkaline magmas on the ore-bearing intrusions and mineralization. Field observations and geochronological data shed light on the spatial and temporal relationships between the

  16. High-rate behaviour of iron ore pellet

    Directory of Open Access Journals (Sweden)

    Gustafsson Gustaf

    2015-01-01

    Full Text Available Iron ore pellets are sintered, centimetre-sized spheres of ore with high iron content. Together with carbonized coal, iron ore pellets are used in the production of steel. In the transportation from the pelletizing plants to the customers, the iron ore pellets are exposed to different loading situations, resulting in degradation of strength and in some cases fragmentation. For future reliable numerical simulations of the handling and transportation of iron ore pellets, knowledge about their mechanical properties is needed. This paper describes the experimental work to investigate the dynamic mechanical properties of blast furnace iron ore pellets. To study the dynamic fracture of iron ore pellets a number of split Hopkinson pressure bar tests are carried out and analysed.

  17. Extraction procedure testing of solid wastes generated at selected metal ore mines and mills

    Science.gov (United States)

    Harty, David M.; Terlecky, P. Michael

    1986-09-01

    Solid waste samples from a reconnaissance study conducted at ore mining and milling sites were subjected to the U.S. Environmental Protection Agency extraction procedure (EP) leaching test Sites visited included mines and mills extracting ores of antimony (Sb), mercury (Hg), vanadium (V), tungsten (W), and nickel (Ni). Samples analyzed included mine wastes, treatment pond solids, tailings, low grade ore, and other solid wastes generated at these facilities Analysis of the leachate from these tests indicates that none of the samples generated leachate in which the concentration of any toxic metal parameter exceeded EPA criteria levels for those metals. By volume, tailings generally constitute the largest amount of solid wastes generated, but these data indicate that with proper management and monitoring, current EPA criteria can be met for tailings and for most solid wastes associated with mining and milling of these metal ores. Long-term studies are needed to determine if leachate characteristics change with time and to assist in development of closure plans and post closure monitoring programs.

  18. Evaluation of the effectiveness of the filtration leaching for uranium recovery from uranium ore

    Directory of Open Access Journals (Sweden)

    Bolat Uralbekov

    2015-09-01

    Full Text Available The physical and chemical processes taking place in filtration leaching of uranium from uranium ore sample by sulphuric acid solution have been studied by modern physico-chemical methods (X-ray diffraction, scanning electron spectroscopy, electron probe microanalysis, optical emission spectroscope, ICP OES. Column leaching test was carried out for ore samples obtained from a uranium in-situ leaching (ISL mining site using deluted sulphuricacid to study the evolution of various elements concentration in the pregnant leach solution. It has been shown that the uranium in pregnant solutions appears by dissolution of calcium and magnesium carbonates and uranium minerals as well. It was found the decreasing of filtration coefficient from 0.099 m day-1 to 0.082 m day-1, due to the presence of mechanical and chemical mudding. Partial extraction of uranium (85% from the ore has been explained by the slow diffusion of sulfuric acid to the uranium minerals locates in the cracks of silicate minerals. It was concluded that the studied uranium ore sample according to adverse geotechnical parameters is not suitable for uranium extraction by filtration leaching.

  19. An investigation into heterogeneity in a single vein-type uranium ore deposit: Implications for nuclear forensics.

    Science.gov (United States)

    Keatley, A C; Scott, T B; Davis, S; Jones, C P; Turner, P

    2015-12-01

    Minor element composition and rare earth element (REE) concentrations in nuclear materials are important as they are used within the field of nuclear forensics as an indicator of sample origin. However recent studies into uranium ores and uranium ore concentrates (UOCs) have shown significant elemental and isotopic heterogeneity from a single mine site such that some sites have shown higher variation within the mine site than that seen between multiple sites. The elemental composition of both uranium and gangue minerals within ore samples taken along a single mineral vein in South West England have been measured and reported here. The analysis of the samples was undertaken to determine the extent of the localised variation in key elements. Energy Dispersive X-ray spectroscopy (EDS) was used to analyse the gangue mineralogy and measure major element composition. Minor element composition and rare earth element (REE) concentrations were measured by Electron Probe Microanalysis (EPMA). The results confirm that a number of key elements, REE concentrations and patterns used for origin location do show significant variation within mine. Furthermore significant variation is also visible on a meter scale. In addition three separate uranium phases were identified within the vein which indicates multiple uranium mineralisation events. In light of these localised elemental variations it is recommended that representative sampling for an area is undertaken prior to establishing the REE pattern that may be used to identify the originating mine for an unknown ore sample and prior to investigating impact of ore processing on any arising REE patterns.

  20. (234)U/(238)U signatures associated with uranium ore bodies: part 1 Ranger 3.

    Science.gov (United States)

    Lowson, Richard T; McIntyre, Mark G

    2013-04-01

    The Ranger 3 ore body is an early Proterozoic U ore body in the Alligator Rivers U province, Northern Territory, Australia. It has surface expression with a redox front located between 30 and 50 m below the surface. The ground water U concentration and (234)U/(238)U AR signature in the top 10 m of the weathered zone are reported for 357 samples collected over 4 wet seasons, at 5 depths, along a transect in-line with the hydraulic gradient and along the centre line of the ore body and its associated dispersion halo. The results show that the weathered zone displays a general U isotope feature for this type of ore body with the (234)U/(238)U AR for the ground water and amorphous phase of the solid matrix being less than 1. The ground water (234)U/(238)U AR is independent of the annual monsoonal climate and depth within the range surface to 10 m. In the vicinity of the U ore body the ground water (234)U/(238)U AR is 0.75 and is very similar to the (234)U/(238)U AR of the amorphous phase of the solid (0.76). The (234)U/(238)U ARs of the amorphous phase and ground water rise and separate to values of 0.88 and 1.02 at the end of the transect. The rise and separation in (234)U/(238)U AR are interpreted as evidence that the source of the U in the ground water is from the water-soluble sub-phase of the amorphous phase and that the ground water flow is too fast to allow the processes occurring across the solid-water interface to reach chemical equilibrium. The data set is a robust characterisation of the coarse and fine detail of the (234)U/(238)U AR signature in the weathered zone of U ore bodies.

  1. Dose calculations for intakes of ore dust

    Energy Technology Data Exchange (ETDEWEB)

    O`Brien, R.S

    1998-08-01

    This report describes a methodology for calculating the committed effective dose for mixtures of radionuclides, such as those which occur in natural radioactive ores and dusts. The formulae are derived from first principles, with the use of reasonable assumptions concerning the nature and behaviour of the radionuclide mixtures. The calculations are complicated because these `ores` contain a range of particle sizes, have different degrees of solubility in blood and other body fluids, and also have different biokinetic clearance characteristics from the organs and tissues in the body. The naturally occurring radionuclides also tend to occur in series, i.e. one is produced by the radioactive decay of another `parent` radionuclide. The formulae derived here can be used, in conjunction with a model such as LUDEP, for calculating total dose resulting from inhalation and/or ingestion of a mixture of radionuclides, and also for deriving annual limits on intake and derived air concentrations for these mixtures. 15 refs., 14 tabs., 3 figs.

  2. Application of neodymium isotope ratio measurements for the origin assessment of uranium ore concentrates.

    Science.gov (United States)

    Krajkó, Judit; Varga, Zsolt; Yalcintas, Ezgi; Wallenius, Maria; Mayer, Klaus

    2014-11-01

    A novel procedure has been developed for the measurement of (143)Nd/(144)Nd isotope ratio in various uranium-bearing materials, such as uranium ores and ore concentrates (UOC) in order to evaluate the usefulness and applicability of variations of (143)Nd/(144)Nd isotope ratio for provenance assessment in nuclear forensics. Neodymium was separated and pre-concentrated by extraction chromatography and then the isotope ratios were measured by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). The method was validated by the measurement of standard reference materials (La Jolla, JB-2 and BCR-2) and the applicability of the procedure was demonstrated by the analysis of uranium samples of world-wide origin. The investigated samples show distinct (143)Nd/(144)Nd ratio depending on the ore type, deposit age and Sm/Nd ratio. Together with other characteristics of the material in question, the Nd isotope ratio is a promising signature for nuclear forensics and suggests being indicative of the source material, the uranium ore.

  3. Determination Systems of Nb and Ta in Geochemical Samples and Rare Earth ores by ICP-MS and ICP-AES%ICP-MS和 ICP -AES 测定地球化学勘查样品及稀土矿石中铌钽方法体系的建立

    Institute of Scientific and Technical Information of China (English)

    高会艳

    2014-01-01

    A method to deal with the conditions of incomplete digestion of geological samples,and the complexity of the analysis for present technologies,along with the routine methods of wet digestion on constant temperature electric heating plate with mixed acids and Na2 O2 fusion pre-treatment method and to ease the hydrolysis of Nb and Ta are describe in this paper. Both Inductively Coupled Plasma-Mass Spectrometry( ICP-MS ) and Inductively Coupled Plasma-Atomic Emission Spectrometry( ICP-AES)were applied to establish two sets of analysis methods which can be used to detect the contents of Nb and Ta in geochemical exploration samples and rare earth ores. Wet digestion on constant temperature electric heating plate is suitable for low content and easy decomposition of samples with nitric acid-hydrofluoric acid-sulfuric acid by ICP-MS. Na2 O2 fusion pre-treatment method is suitable for high content and insoluble samples by using ICP-AES. Through the analysis of a series of national certified reference samples of soil,stream sediments,rocks and rare earth ores,the results show that mixed acid pre-treatment coupled with ICP-MS had a linear range of 0-200 ng/mL and detection limits of Nb and Ta were 0 . 01 μg/g and 0. 05 μg/g,respectively. The relative error was less than 10%,and the relative standard deviation( RSD)was less than 6%. The Na2 O2 fusion pre-treatment coupled with ICP-AES had a linear range of 0 -30 μg/mL, detection limits of Nb and Ta were 0. 2 μg/g and 2. 5 μg/g,respectively. The relative error was less than 10%, and the precision( RSD)was less than 7%. The two sets of analysis method satisfy the demand of analysis of Nb and Ta in samples with a complex matrix,a large range of content and large quantities of samples.%针对目前铌钽分析中出现的样品溶解不完全、元素易水解及现有分析技术流程复杂的情况,本文对常用的混合酸恒温电热板溶解和过氧化钠碱熔两种样品前处理方式

  4. [Spectral characteristics and implications of quartz from Heliao lead-zinc polymetallic ore district in the south of Qinzhou-Hangzhou joint belt].

    Science.gov (United States)

    Lü, Wen-Chao; Yang, Zhi-Jun; Zhou, Yong-Zhang; Li, Hong-Zhong; Zeng, Xiang-Qing; Chen, Qing; Liang, Jin; Zeng, Chang-Yu

    2013-05-01

    The XRD, FTIR and Raman spectrum were employed to study the characters of quartz from three types of rock samples, which are mineralized rock sample, near ore body rock sample and far away from ore body rock sample in Heliao lead-zinc polymetallic ore district. The research shows that the quartz in the mineralized rock and far away from ore body rock is pure, while the quartz in near ore body rock contains a small amount of impurities. But such small amounts of impurities did not cause apparent change in the quartz lattice parameters. From far away from ore body rock-->near ore body rock-->mineralized rock, the crystallinity and order degree of quartz are higher and higher. And the quartz in the mineralized rock has a trend to change into low symmetry quartz. It's a unique to mineralized rock that the quartz's absorption peak at 1 050 cm(-1) was split into two strongest ones. It can be used as the signs of whether exists mineralization. The cause for the quartz microstructure changes may be related to the activities of late mineralized hydrothermal fluids. Late hydrothermal influence was very weak to the quartz far away from ore body rock. And through the impact of the multi-stage hydrothermal effect, the quartz in mineralized rock may be purified by recrystallization and structural adjustment. However the quartz in near ore body rock didn't have enough hydrothermal influence, so it's not pure. Genealogy research technology is a useful technique for in-depth exploration of study area mineralization process and metallogenic regularity.

  5. Iron ore weathering potentials of ectomycorrhizal plants.

    Science.gov (United States)

    Adeleke, R A; Cloete, T E; Bertrand, A; Khasa, D P

    2012-10-01

    Plants in association with soil microorganisms play an important role in mineral weathering. Studies have shown that plants in symbiosis with ectomycorrhizal (ECM) fungi have the potential to increase the uptake of mineral-derived nutrients. However, it is usually difficult to study many of the different factors that influence ectomycorrhizal weathering in a single experiment. In the present study, we carried out a pot experiment where Pinus patula seedlings were grown with or without ECM fungi in the presence of iron ore minerals. The ECM fungi used included Pisolithus tinctorius, Paxillus involutus, Laccaria bicolor and Suillus tomentosus. After 24 weeks, harvesting of the plants was carried out. The concentration of organic acids released into the soil, as well as potassium and phosphorus released from the iron ore were measured. The results suggest that different roles of ectomycorrhizal fungi in mineral weathering such as nutrient absorption and transfer, improving the health of plants and ensuring nutrient circulation in the ecosystem, are species specific, and both mycorrhizal roots and non-mycorrhizal roots can participate in the weathering process of iron ore minerals.

  6. Isotopic Characteristics of Mesozoic Au-Ag Polymetallic Ore Deposits in Northern Hebei and Their Ore-Forming Materials Source

    Institute of Scientific and Technical Information of China (English)

    王宝德; 牛树银; 孙爱群; 李红阳

    2003-01-01

    It has long been a controversy about the source of ore-forming materials of Au-Agpolymetallic deposits both in metallogenic theory and in ore-searching practice. In terms of alarge wealth of the isotopic statistics data from Indosinian-Yanshanian endogenic ore deposits innorthern Hebei (generally referring to the areas along the northern part of Taihang Mountainsand northern Hebei, the same below) , it is considered that the ore-forming materials came fromthe deep interior of the Earth, which had migrated through plumes to the Earth surface while ex-perienced multi-stage evolution and then emplaced progressively in favorable structural loci toform ores. Their isotope data show that 559 sulfur isotopic data from 40 ore deposits are, for themost part, within the range of - 5‰ - 5‰, with a high degree of homogenization, indicatingthat the sulfur is derived mainly from magma; 200 lead isotope data from 37 ore deposits indi-cate that the ore-forming materials are principally of mantle source though some crust-source ma-terial was involved; 96 oxygen, hydrogen and carbon isotope data from 34 ore deposits illustratethat the ore-forming fluids are dominated by magmatic water while other sources of water wouldbe involved. It may therefore be seen that the formation of endogenic deposits has nothing to dowith the strata.

  7. Physical-chemical conditions of ore deposition

    Science.gov (United States)

    Barton, P.B.

    1981-01-01

    Ore deposits form under a wide range of physical and chemical conditions, but those precipitating from hot, aqueous fluids-i.e. the hydrothermal deposits-form generally below 700??C and at pressures of only 1 or 2 kbar or less. Natural aqueous fluids in rocks may extract metal and sulfur from a variety of rock types or may acquire them as a residual heritage from a crystallizing silicate magma. Ore-forming hydrothermal fluids never appear as hot springs (except in deep, submarine situations) because they boil, mix with surface waters, and cool, thereby losing their ore-bearing ability before reaching the surface. Mineral systems function as chemical buffers and indicators just as buffers and indicators function in a chemical laboratory. By reading the record written in the buffer/indicator assemblages of minerals one can reconstruct many aspects of the former chemical environment. By studying the record of changing conditions one may deduce information regarding the processes functioning to create the succession of chemical environments and the ore deposits they represent. The example of the OH vein at Creede, Colorado, shows a pH buffered by the K-feldspar + muscovite + quartz assemblage and the covariation of S2 and O2 buffered by the assemblage chlorite + pyrite + quartz. Boiling of the ore fluid led to its oxidation to hematite-bearing assemblages and simultaneously produced an intensely altered, sericitic capping over the vein in response to the condensation of vapors bearing acidic components. The solubility of metals as calculated from experimental and theoretical studies of mineral solubility appears too low by at least one or two powers of ten to explain the mineralization at Creede. In contrast to Creede where the mineral stabilities all point to a relatively consistent chemistry, the Mississippi Valley type deposits present a puzzle of conflicting chemical clues that are impossible to reconcile with any single equilibrium situation. Thus we must

  8. Physical-chemical conditions of ore deposition

    Science.gov (United States)

    Barton, Paul B.

    Ore deposits form under a wide range of physical and chemical conditions, but those precipitating from hot, aqueous fluids-i.e. the hydrothermal deposits-form generally below 700°C and at pressures of only 1 or 2 kbar or less. Natural aqueous fluids in rocks may extract metal and sulfur from a variety of rock types or may acquire them as a residual heritage from a crystallizing silicate magma. Ore-forming hydrothermal fluids never appear as hot springs (except in deep, submarine situations) because they boil, mix with surface waters, and cool, thereby losing their ore-bearing ability before reaching the surface. Mineral systems function as chemical buffers and indicators just as buffers and indicators function in a chemical laboratory. By reading the record written in the buffer/indicator assemblages of minerals one can reconstruct many aspects of the former chemical environment. By studying the record of changing conditions one may deduce information regarding the processes functioning to create the succession of chemical environments and the ore deposits they represent. The example of the OH vein at Creede, Colorado, shows a pH buffered by the K-feldspar + muscovite + quartz assemblage and the covariation of S 2 and O 2 buffered by the assemblage chlorite + pyrite + quartz. Boiling of the ore fluid led to its oxidation to hematite-bearing assemblages and simultaneously produced an intensely altered, sericitic capping over the vein in response to the condensation of vapors bearing acidic components. The solubility of metals as calculated from experimental and theoretical studies of mineral solubility appears too low by at least one or two powers of ten to explain the mineralization at Creede. In contrast to Creede where the mineral stabilities all point to a relatively consistent chemistry, the Mississippi Valley type deposits present a puzzle of conflicting chemical clues that are impossible to reconcile with any single equilibrium situation. Thus we must

  9. 40 CFR 440.10 - Applicability; description of the iron ore subcategory.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Iron Ore Subcategory § 440.10 Applicability; description of the iron ore subcategory. The provisions of this subpart A are applicable to discharges from (a) mines operated to obtain iron ore, regardless of the type of ore...

  10. EXPLANATORY MODEL OF SPOT PRICE OF IRON ORE

    Directory of Open Access Journals (Sweden)

    Juan Enrique Villalva A.

    2015-11-01

    Full Text Available The objective of this study was to construct an explanatory model of the spot price of iron ore in the international market. For this, the method of multiple linear regressions was used. As a dependent variable, the spot price of iron ore (62% Fe China Tianjin port was taken, between 2010 and 2013. As independents variables were taken seven variables of international iron ore market. The resulting model includes variables: Iron ore inventory in Chinese ports, Baltic Dry Index (BDI, Iron ore exports from Brazil & Australia and Chinese Rebar Steel Price, as explanatory variables of the behavior of the spot price of iron ore in the international market. The model has an adjusted coefficient of determination R2 of 0.90, and was validated by comparing its predictions vs. known values of 2014.

  11. Genesis of Gold- Silver Deposits in Qingchengzi Ore Field

    Institute of Scientific and Technical Information of China (English)

    Wei Min

    2001-01-01

    The gold - silver complex ore field of Qingchengzi is located in Liaohe group of Liaodong rift. The gold - silver ore bodies mainly lie in Dashiqiao group and Gaixian group, which provides ore - forming materials for the mineralization. For taking place multi - period and multi - stage magmatic activities, the ore - forming materials in the formation had had dynamothermal metamorphism for a long time and enriched and formed ore bodies after magmatism in Indo- Chinese and Yanshan epoch. The ore bodies are controlled by stratigraphic formation and stored in the interformational faults and schistosity belts. Silicalite is the most important indicator for searching them. Although the Pb - Zn and the gold - silver deposits are the same series of mineralized products, their positions are different, resulting from the differences of elements nature and mineralized conditions. The gold silver deposits belong to strata - bound and hysterogenetic mesothermal - epithermal deposit.

  12. Source of ore-forming material for the Huangtuliang gold deposit, Hebei Province and ore prospecting in the deep periphery

    Institute of Scientific and Technical Information of China (English)

    NIU Shuyin; SUN Aiqun; WANG Baode; HAN Yuchou; WEI Minghui; ZHANG Hai; ZHANG Ge; SHI Ping; WANG Wenxing

    2008-01-01

    The Huangtuliang gold deposit is characterized by its wide and large ore belt, stable extension and closely spaced orebodies. Unfortunately, no orebody was found by deep drilling. As a result, ore prospecting in this region was once put into dilemma. Detailed analysis of ore-forming and ore-controlling structures in the mining district by the authors has revealed that the ore-forming and ore-controlling structure in this mining district is a steeply dipping (85°-110°/∠70°-85° N-NNE), spade-shaped ductile shear zone, and the ore-controlling structures are a series of nearly erected second-ordered faults which are developed in the upper part of the ductile shear zone, intersecting with the ductile shear zone. Deep cutting of the ductile shear zone made it possible the ascending of ore fluids from the mantle plume at depth and these ore fluids would migrate upwards along the ductile shear zone under certain temperature and pressure conditions. Along their ascending path, the ore fluids would extract ore-forming elements from the country rocks and the extracted ore-forming elements would be deposited as ores in the hanging-wall second-ordered faults. The reason why no orebody was found in early prospecting at depth is that northward-dipping drilling in the southern part of the shear zone extended so deeply as to be beneath the shear zone. Only shallow-level orebodies could be found by southward-dipping drilling practice in the northern part of the shear zone.The location where deep-seated orebodies occurred shifted northwards and the orebodies occurred at greater depth.Therefore, it is natural that no orebody could be found when drill core passed through the shear zone. After the ore-forming and ore-controlling structures were well understood, the focus of ore prospecting was placed on the deep-level, northward-penetrating veins. In this way a number of new blind orebodies of great thickness have been found. On the basis of research development in the mining

  13. Contact angle of water on iron ore fines: Measurement and analysis

    Directory of Open Access Journals (Sweden)

    Huang X.B.

    2015-01-01

    Full Text Available The relative contact angle (θRCA for seven iron ore fines was measured by using Washburn Osmotic Pressure method under laboratory conditions. By choosing cyclohexane as the reference that can perfectly wet iron ore particles, the relative contact angles were measured and varied from 57° to 73°. With the volume % of goethite (φG as the variable, a new model for relative contact angle was developed. The expected relative contact angle for pure goethite is about 56°, while that for goethite free samples is about 77°. Physical properties, such as surface morphology (SMI and pore volume (Vpore can influence the relative contact angle. The φG can be expressed as a function of SMI and VPore. Thus, we inferred that the relative contact angle is a function of φG for the iron ores used. The measured relative contact angles were found to be in good agreement (Radj 2 >0.97 with the calculated ones based on the research from Iveson, et al. (2004. Comparing with the model developed by Iveson et al.(2004, the new model for contact angle proposed in this paper is similar, but more detailed with two meaningful physical parameters. The modification of physicochemical properties on iron ores would be another topic in the further study on granulation.

  14. Sulfuric acid leaching of mechanically activated manganese carbonate ore

    Directory of Open Access Journals (Sweden)

    Kenan Yıldız

    2010-06-01

    Full Text Available Acidic leaching of mechanically activated manganese ore from Denizli – Tavas was investigated. The ore was activated mechanically in a planetary mill and the amorphisation in manganese structure was analyzed with X-ray diffraction. The parameters in acidic leaching of the ore were milling time, acid concentration and time. All experiments were performed at 25°C with solid to liquid ratio: 1/10. The activation procedure led to amorphization and structural disordering in manganese ore and accelerated the dissolution of manganese in acidic media.

  15. Tectonomagmatic Metallogenic System of Dexing Ore Field, Jiangxi, China

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    13 ore deposits and a large number of ore occurrences cluster in Dexing ore field which is 20 km long and 12 km wide. The tectonic evolution, magmatism, as well as the metallogeny are controlled by the Northeast Jiangxi deep-seated fracture belt (NJDFB). The source is believed to have been derived from the Meso-Neoproterozoic marine volcanism. The magmatic activity of Mesozoic I-type granite could have provided the metal elements, thermal fluid, heat, and the space for ore-forming processes. A unified geological model is proposed, which combines the tectonism, magmatism and metallogeny as the basic control of the giant metal mineralizations.

  16. Pros and Cons,Iron Ore Price Hikes

    Institute of Scientific and Technical Information of China (English)

    Tang Jingtao

    2008-01-01

    @@ Backaround Baostecl and CVRD reached an agreement on the price hikes of 65 percent and 71 percent in February.And in June Baosteel and Rio Tinto which is the largest iron ore company in Australia reached an agreement on the price hikes of 79.88 percent on the iron ore fines and 96.5 percent on the iron ore lumps.This is the first time that two kinds of the iron ore price grew at the same time in Asian market.

  17. Study of the dielectric parameters of aluminium ore bauxite of Mainpat area of Chhattisgarh at X-band frequency

    Indian Academy of Sciences (India)

    S K Srivastava; B R Vishwakarama

    2004-08-01

    A simple method for measuring the dielectric parameter of materials in the form of powders at microwave frequencies is suggested. Measurement of the permittivity $\\varepsilon'$ and $\\varepsilon''$ at 9.967 GHz on powder samples of the aluminum ore bauxite gives interesting results. It is found that $\\varepsilon'$ and $\\varepsilon''$ increases with packing densities(). Further $\\varepsilon'$ and $\\varepsilon''$ also depend upon the percentage of Al23. These results show that the values of $\\varepsilon'$ and $\\varepsilon''$ can be used to set certain basic values for minability of the ore for a particular sample. Conductivities () and relaxation () are also calculated in the present studies.

  18. Innovative methodology for comprehensive utilization of iron ore tailings: part 1. The recovery of iron from iron ore tailings using magnetic separation after magnetizing roasting.

    Science.gov (United States)

    Li, Chao; Sun, Henghu; Bai, Jing; Li, Longtu

    2010-02-15

    Iron ore tailings have become one kind of the most hazardous solid waste. In order to recycle iron in the tailings, we present a technique using magnetizing roasting process followed by magnetic separation. After analysis of chemical composition and crystalline phase, according to experimental mechanism, the effects of different parameters on recovery efficiency of iron were carried out. The optimum reaction parameters were proposed as the following: ratio of coal: iron ore tailings as 1:100, roasting at 800 degrees C for 30 min, and milling 15 min of roasted samples. With these optimum parameters, the grade of magnetic concentrate was 61.3% Fe and recovery rate of 88.2%. With this method, a great amount of iron can be reused. In addition, the microstructure and phase transformation of the process of magnetizing roasting were studied.

  19. Remobilisation features and structural control on ore grade distribution at the Konkola stratiform Cu-Co ore deposit, Zambia

    OpenAIRE

    Torremans, K.; Gauquie, J.; Boyce, A. J.; Barrie, C.D.; Sikazwe, O.; Muchez, P.H.

    2013-01-01

    The Konkola deposit is a high grade stratiform Cu–Co ore deposit in the Central African Copperbelt in Zambia. Economic mineralisation is confined to the Ore Shale formation, part of the Neoproterozoic metasedimentary rocks of the Katanga Supergroup. Petrographic study reveals that the copper–cobalt ore minerals are disseminated within the host rock, sometimes concentrated along bedding planes, often associated with dolomitic bands or clustered in cemented lenses and in layer-parallel and irre...

  20. Role of ore mineralogy in optimizing conditions for bioleaching low-grade complex sulphide ores

    Institute of Scientific and Technical Information of China (English)

    P. A. OLUBAMBI; S. NDLOVU; J. H. POTGIETER; J. O. BORODE

    2008-01-01

    The role that ore mineralogy plays in understanding and optimizing the conditions favouring the bioleaching of complex sulphide ore containing high amounts of siderite was studied using mixed cultures of mesophilic bacteria, with emphasis on zinc,lead and copper recoveries. The influencing parameters investigated include particle size, stirring speed, volume of inoculum, pulp density, and pH. The results show that the mixed mesophilic cultures can extract about two and a half times the amount of zinc than copper over an equivalent period of time. The highest zinc and copper recoveries of 89.2% and 36.4% respectively are obtained at particle size of 75 μm, stirring speed of 150 r/min, pulp density of 10% (w/v), 12% (v/v) inoculum concentration, and a pH of 1.6. Variations in elemental composition within different particle sizes resulting from the mineralogy of the ore account for the bioleaching behaviour at varying particle sizes. The dissolution at varying pulp density, volume of inoculum, solution pH and the low solution potential observed are also influenced by ore mineralogy.

  1. Bioprocessing of ores: Application to space resources

    Science.gov (United States)

    Johansson, Karl R.

    The role of microorganisms in the oxidation and leaching of various ores (especially those of copper, iron, and uranium) is well known. This role is increasingly being applied by the mining, metallurgy, and sewage industries in the bioconcentration of metal ions from natural receiving waters and from waste waters. It is concluded that bioprocessing using bacteria in closed reactors may be a variable option for the recovery of metals from the lunar regolith. Obviously, considerable research must be done to define the process, specify the appropriate bacteria, determine the necessary conditions and limitations, and evaluate the overall feasibility.

  2. Project StORe: Social Science report

    OpenAIRE

    Burton, Guy

    2006-01-01

    There was widespread support across the social science research community regarding the aims of the StORe Project Nearly half of social science respondents claimed that both source-to-output and out-put-to source repositories would offer a ‘significant advantage to my work’; a third in both cases claimed it would be ‘useful but not of major significance’ Postgraduate students were generally more enthusiastic about source-to-output and output-to-source repositories than acade...

  3. Sedimentary exhalative nickel-molybdenum ores in south China

    Science.gov (United States)

    Lott, D.A.; Coveney, R.M.; Murowchick, J.B.; Grauch, R.I.

    1999-01-01

    Unique bedded Ni-Mo ores hosted by black shales were discovered in localized paleobasins along the Yangzte platform of southern China in 1971. Textural evidence and radiometric dates imply ore formation during sedimentation of black shales that grade into readily combustible beds, termed stone coals, which contain 10 to 15 percent organic carbon. Studies of 427 fluid inclusions indicate extreme variation in hydrothermal brine salinities that were contained by Proterozoic dolostones underlying the ore zone in Hunan and Guizhou. Variations of fluid inclusion salinities, which range from 0.1 to 21.6 wt percent NaCl equiv, are attributed to differences in the compositions of brines in strata underlying the ore bed, complicated by the presence of seawater and dilute fluids that represent condensates of vapors generated by boiling of mineralizing fluids or Cambrian meteoric water. The complex processes of ore deposition led to scattered homogenization temperatures ranging from 100??to 187??C within the Hunan ore zone and from 65??to 183??C within the Guizhou ore zone. While living organisms probably did not directly accumulate metals in situ in sufficient amounts to explain the unusually high grades of the deposits, sulfur isotope ratios indicate that bacteria, now preserved as abundant microfossils, provided sufficient sulfide for the ores by reduction of seawater sulfate. Such microbiota may have depended on vent fluids and transported organic matter for key nutrients and are consistent with a sedex origin for the ores. Vent fluids interacted with organic remains, including rounded fragments of microbial mats that were likely transported to the site of ore deposition by the action of waves and bottom currents prior to replacement by ore minerals.

  4. Mixed State and High Effective Utilization of Pilbara Blending Iron Ore Powder%Mixed State and High Effective Utilization of Pilbara Blending Iron Ore Powder

    Institute of Scientific and Technical Information of China (English)

    CAO Yong-guo; WU Sheng-li; HAN Hong-liang; WANG Hong-wei; XUE Fang; LIU Xiao-qin

    2011-01-01

    Pilbara blending iron ore powder (PB powder) is blending ores with good and poor quality iron ores, so how to use PB power effectively is a problem. The self-characteristics of PB powder and its single-components were studied respectively such as the macroscopic properties, microscopic properties, and high-temperature properties the behavior and effect in the sintering were mastered. Then based on the new ore-proportioning idea of iron ores sintering characteristics complementary, the principles on the effective use of PB powder were discussed, and was fur ther validated through the sintering pot test and industrial production. The results show that PB powder is composed of three kinds of iron ore, and the sintering characteristics of different iron ores are obviously discrepant. With the ore-proportioning optimization based on the iron ores sintering characteristics complementary, the proportion of PB iron ore powder can be increased to more than 45 %.

  5. A novel acidophile community populating waste ore deposits at an acid mine drainage site

    Institute of Scientific and Technical Information of China (English)

    HAO Chun-bo; ZHANG Hong-xun; BAI Zhi-hui; HU Qing; ZHANG Bao-guo

    2007-01-01

    Waste ore samples (pH 3.0) were collected at an acid mine drainage site in Anhui, China. The present acidophilic microbial community in the waste ore was studied with 16S rRNA gene clone library and denaturing gradient gel electrophoresis (DGGE). Eighteen different clones were identified and affiliated with Actinobacteria, low G + C Gram-positives, Thermomicrobia, Acidobacteria, Proteobacteria, Candidate division TM7, and Planctomycetes. Phylogenetic analysis of 16S rRNA gene sequences revealed a diversity of acidophiles in the samples that were mostly novel. It is unexpected that the moderately thermophilic acidophiles were abundant in the acidic ecosystem and may play a great role in the generation of AMD. The result of DGGE was consistent with that of clone library analysis. These findings help in the better understanding of the generation mechanism of AMD and in developing a more efficient method to control AMD.

  6. Synthesis of Fe-MCM-41 Using Iron Ore Tailings as the Silicon and Iron Source.

    Science.gov (United States)

    Li, Xin; Yu, Honghao; He, Yan; Xue, Xiangxin

    2012-01-01

    Highly ordered Fe-MCM-41 molecular sieve was successfully synthesized by using n-hexadecyl-trimethyl ammonium bromide (CTAB) as the template and the iron ore tailings (IOTs) as the silicon and iron source. X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), diffuse reflectance UV-visible spectroscopy, (29)Si magic-angle spinning (MAS) nuclear magnetic resonance (NMR), and nitrogen adsorption/desorption were used to characterize the samples. The results showed that the mesoporous materials had highly ordered 2-dimensional hexagonal structure. The synthesized sample had high surface area, and part of iron atoms is retained in the framework with formation of tetrahedron after removal of the template by calcinations. The results obtained in the present work demonstrate the feasibility of employing iron ore tailings as a potential source of silicon and iron to produce Fe-MCM-41 mesoporous materials.

  7. Synthesis of Fe-MCM-41 Using Iron Ore Tailings as the Silicon and Iron Source

    Directory of Open Access Journals (Sweden)

    Xin Li

    2012-01-01

    Full Text Available Highly ordered Fe-MCM-41 molecular sieve was successfully synthesized by using n-hexadecyl-trimethyl ammonium bromide (CTAB as the template and the iron ore tailings (IOTs as the silicon and iron source. X-ray diffraction (XRD, high-resolution transmission electron microscopy (HRTEM, diffuse reflectance UV-visible spectroscopy, 29Si magic-angle spinning (MAS nuclear magnetic resonance (NMR, and nitrogen adsorption/desorption were used to characterize the samples. The results showed that the mesoporous materials had highly ordered 2-dimensional hexagonal structure. The synthesized sample had high surface area, and part of iron atoms is retained in the framework with formation of tetrahedron after removal of the template by calcinations. The results obtained in the present work demonstrate the feasibility of employing iron ore tailings as a potential source of silicon and iron to produce Fe-MCM-41 mesoporous materials.

  8. Investigation of sulphur isotope variation due to different processes applied during uranium ore concentrate production.

    Science.gov (United States)

    Krajkó, Judit; Varga, Zsolt; Wallenius, Maria; Mayer, Klaus; Konings, Rudy

    The applicability and limitations of sulphur isotope ratio as a nuclear forensic signature have been studied. The typically applied leaching methods in uranium mining processes were simulated for five uranium ore samples and the n((34)S)/n((32)S) ratios were measured. The sulphur isotope ratio variation during uranium ore concentrate (UOC) production was also followed using two real-life sample sets obtained from industrial UOC production facilities. Once the major source of sulphur is revealed, its appropriate application for origin assessment can be established. Our results confirm the previous assumption that process reagents have a significant effect on the n((34)S)/n((32)S) ratio, thus the sulphur isotope ratio is in most cases a process-related signature.

  9. STUDY ON BIOLEACHING OF PRIMARY CHALCOPYRITE ORE WITH THERMOACIDOPHLIC ARCHAE

    Institute of Scientific and Technical Information of China (English)

    P. Zou; W.B. Zhang; T. Lei; J.K. Wang

    2006-01-01

    A high temperature-tolerating thermoacidophilic archae (TA) was isolated from water samples collected from a hot sulfur-containing spring in the Yunnan Province, China, and was used in bioleaching experiments of a low-grade chalcopyrite ore. The TA grow at temperatures ranging from 40 to 80℃, with 65℃ being the optimum temperature, and at pH values of 1.5 to 4.0, with an optimum pH value of 2.0. The bioleaching experiments of the chalcopyrite ore were conducted in both laboratory batch bioreactors and leaching columns. The results obtained from the bioreactor experiments showed that the TA bioleaching rate of copper reached 97% for a 12-day leaching period, while the bioleaching rate was 32.43% for thiobacillus ferrooxidans (Tf) leaching for the same leaching time. In the case of column leaching, tests of a two-phase leaching (196 days), that is,a two-month (56 days) Tf leaching in the first phase, followed by a 140-day TA leaching in the second phase were performed. The average leaching rate of copper achieved for the 140-day TA leaching was 195mg/(L· d), while for the control experiments, it was as low as 78mg/(L· d) for the Tf leaching, indicating that the TA possesses a more powerful oxidizing ability to the chalcopyrite than Tf. Therefore, it is suggested that the two-phase leaching process be applied to for the heap leaching operations, whereas, the TA can be used in the second phase when the temperature inside the heap has increased, and the primary copper sulfide minerals have already been partially oxidized with Tf beforehand in the first phase.

  10. PRACTICAL AND PREDICTIVE MODELLING OF ORE DEPOSITS IN HYDROTHERMAL SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    ZHAO Chong-bin; B.E.Hobbs; H.B.Muhlhaus; A.Ord

    2001-01-01

    @@ Over the past five years,we have been making efforts to develop a practical and predictive tool to explore for giant ore deposits in hydrothermal systems.Towards this goal,a significant progress has been made towards a better understanding of the basic physical and chemical processes behind ore body formation and mineralization in hydrothermal systems.

  11. PRACTICAL AND PREDICTIVE MODELLING OF ORE DEPOSITS IN HYDROTHERMAL SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    ZHAO; Chong-bin; B.E.Hobbs; H.B.Muhlhaus; A.Ord

    2001-01-01

    Over the past five years,we have been making efforts to develop a practical and predictive tool to explore for giant ore deposits in hydrothermal systems.Towards this goal,a significant progress has been made towards a better understanding of the basic physical and chemical processes behind ore body formation and mineralization in hydrothermal systems.……

  12. Experimental study of ore gabbro liquid immiscibility

    Institute of Scientific and Technical Information of China (English)

    SANG; Zunan; XIA; Bin; ZHOU; Yongsheng; JIN; Zhenmin

    2005-01-01

    In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, China. Experiments were conducted under (confining) pressure ranging from 450 to 500 MPa and temperature of 900-1200℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

  13. The equipment for monitoring of chemical composition of complex ores RLP-21.

    Directory of Open Access Journals (Sweden)

    Yefimenko S. A.

    2009-04-01

    Full Text Available The portable energy dispersive X-ray fluorescent spectrometer (EDXRF RLP-21 enables to carry out an express X-ray radiometric analysis of ore and samples, of concentrating and metallurgical manufactures products, defining 35 elements simultaneously. RLP-21 is designed to detect low silver and cadmium content. The main principles forming a basis of a spectrometer’s functioning, opportunities of the software, metrological characteristics are stated in this article.

  14. Excited response of granular ores in vibrating field

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The dynamical theory was utilized to probe into the law of the excited response of granular ores generated by the exciting action of exciter and the influence of wave propagation in vibrating field. The exciter with double axes was presented as an example, and the principle of exciter and its mathematical expression of the excitation force were given. The granular ores have viscidity and damping speciality, on the basis of which the motion equation of excited response of ores was established and the approximate expression of mode-displacement by harmonic excitation and the steady effect solution of coordinate response were deduced. Utilizing the step-by-step integration method, the recursion relation matrix of displacement, velocity and acceleration of the excited response of ores were obtained, and the computational flow chart and a computational example were given. The results show that the excited response can change the dynamical character and the flowing characteristic of granular ores.

  15. Current methods and possibilities to determine the variability of Cu content in the copper ore on a conveyor belt in one of KGHM Polska Miedz S.A. mines

    Directory of Open Access Journals (Sweden)

    Jurdziak Leszek

    2016-01-01

    Full Text Available In this paper the methodology of ore sampling on a belt conveyor in one of KGHM Polska Miedz S.A. mines was presented together with the results of analysis of the variation of ore tonnage and quality. The ore was transferred from one mine to another one through the analysed transfer conveyor on the route from the mine Division of Mining to copper plants. The transported ore was sampled in person from Division of Concentrators on a regular basis for metal accounting purposes between both mines. The ore quality control became a significant problem since it is impossible to predict with satisfactory advance both Cu content in the feed as well as its lithology composition which is required to improve and optimise the enrichment efficiency.

  16. Effect of reduction roasting by using bio-char derived from empty fruit bunch on the magnetic properties of Malaysian iron ore

    Institute of Scientific and Technical Information of China (English)

    Nurul A. Yunus; Mohd H. Ani; Hamzah M. Salleh; Rusila Z. A. Rashid; Tomohiro Akiyama; Hadi Purwanto; Nur E. F. Othman

    2014-01-01

    Beneficiation of Malaysian iron ore is becoming necessary as iron resources are depleting. However, the upgrading process is challenging because of the weak magnetic properties of Malaysian iron ore. In this study, bio-char derived from oil palm empty fruit bunch (EFB) was utilized as an energy source for reduction roasting. Mixtures of Malaysian iron ore and the bio-char were pressed into briquettes and subjected to reduction roasting processes at 873-1173 K. The extent of reduction was estimated on the basis of mass loss, and the mag-netization of samples was measured using a vibrating sample magnetometer (VSM). When reduced at 873 K, the original goethite-rich ore was converted into hematite. An increase in temperature to 1073 K caused a significant conversion of hematite into magnetite and enhanced the magnetic susceptibility and saturation magnetization of samples. The magnetic properties diminished at 1173 K as the iron ore was par-tially reduced to wustite. This reduction roasting by using the bio-char can assist in upgrading the iron ore by improving its magnetic proper-ties.

  17. Effect of reduction roasting by using bio-char derived from empty fruit bunch on the magnetic properties of Malaysian iron ore

    Science.gov (United States)

    Yunus, Nurul A.; Ani, Mohd H.; Salleh, Hamzah M.; Rashid, Rusila Z. A.; Akiyama, Tomohiro; Purwanto, Hadi; Othman, Nur E. F.

    2014-04-01

    Beneficiation of Malaysian iron ore is becoming necessary as iron resources are depleting. However, the upgrading process is challenging because of the weak magnetic properties of Malaysian iron ore. In this study, bio-char derived from oil palm empty fruit bunch (EFB) was utilized as an energy source for reduction roasting. Mixtures of Malaysian iron ore and the bio-char were pressed into briquettes and subjected to reduction roasting processes at 873-1173 K. The extent of reduction was estimated on the basis of mass loss, and the magnetization of samples was measured using a vibrating sample magnetometer (VSM). When reduced at 873 K, the original goethite-rich ore was converted into hematite. An increase in temperature to 1073 K caused a significant conversion of hematite into magnetite and enhanced the magnetic susceptibility and saturation magnetization of samples. The magnetic properties diminished at 1173 K as the iron ore was partially reduced to wustite. This reduction roasting by using the bio-char can assist in upgrading the iron ore by improving its magnetic properties.

  18. Analysis of the Ore-Controlling Structure of Ductile Shear Zone Type Gold Deposit in Southern Beishan Area, Gansu, Northwest China

    Institute of Scientific and Technical Information of China (English)

    Chen Bailin; Wu Ganguo; Ye Dejin; Liu Xiaochun; Shu Bin; Yang Nong

    2007-01-01

    The ductile shear zone-type gold deposit is a kind that both the ore-forming mechanism and ore-controlling factors are closely related to the ductile shear zone and its evolution. Ductile shear zone develops in Beishan area, Gansu of Northwest China, and develops especially well in the south belt.The controls of the ductile shear zone on gold deposits are as follows. (1) The regional distribution of gold deposits (and gold spots) is controlled by the ductile shear zone. (2) The ductile-brittle shear zone is formed in the evolution process of ductile shear zone and both are only ore-bearing structures and control the shape, attitude, scale, and distribution of mineralization zones and ore-bodies. (3) Compresso-shear ductile deformation results in that the main kind of gold mineralization is altered mylonite type and the main alteralization is metasomatic. (4) Ore-bearing fracture systems are mainly P-type ones, some D-type and R-type ones, but only individual R'-type and T-type ones. (5) Dynamic differentiation and dynamic metamorphic hydrothermal solution resulting from ductile deformation is one of the sources of ore-forming fluid of gold mineralization, and this is identical with that ore-forming materials are mainly from metamorphic rocks, and ore-forming fluid is mainly composed of metamorphic water, and with the fluid inclusion and geo-chemical characteristics of the deposit. (6) There is a negative correlation between the gold abundance and susceptibility anisotropy (P) of the altered mylonlte samples from the deposit, which shows that the gold mineralization is slightly later than the structural deformation. All above further expound the ore-forming model of the ductile shear zone type of gold deposits.

  19. Electro-Thermal and Semiconductivity Behaviour of Natural Sintered Complex Carbonate Ore for Thermo-Technological Applications

    OpenAIRE

    Loutfy H. Madkour

    2014-01-01

    The polymetal (Zn, Pb, Fe, Ca, Mg, Cd, Ba, Ni, Ti, and SiO2) complex Umm-Gheig carbonate ore is subjected to sintering treatment at 573, 773, 973 and 1273 K respectively for four hours. Chemical, spectral, X-ray and differential thermal analyses are applied for the native ore as well as for the samples preheated and sintered. The current versus applied DC voltage (I–V) characteristics, bulk density (Db), percent shrinkage (%S), activation energy (Ea) and energy gap (Eg) are established for th...

  20. Evaluation and development of integrated technology of rare metal concentrate production in high-level ore processing at Zashikhinsk deposit

    Science.gov (United States)

    Khokhulya, MS; Mukhina, TN; Ivanova, V. A.; Mitrofanova, G. V.; Fomin, A. V.; Sokolov, VD

    2017-02-01

    The authors discuss material constitution of columbite ore sample and recommend optimized pretreatment modes to obtain ball milling products at the maximum dissociation of ore minerals in aggregates. A concentration technology is proposed, with division of material into two flows –0.315 mm and –0.2 mm in sizes, generated in the milling and screening cycles and subjected to gravity–magnetic and magnetic–gravity treatment, respectively. It is shown that the technology ensures production of both tantalum–niobium and zircon concentrates. It has become possible to additionally recover rare metal components Nb2O5 and ZrO2 from tailings through flotation.

  1. The Effects of Ore Properties on the Characterization of Suspension in Settling and Compression

    Directory of Open Access Journals (Sweden)

    Majid Unesi

    2014-06-01

    Full Text Available Many studies have considered the effects of suspension properties on the dewatering process but fewhave focused on ore properties. Thus, the present work studied the effects of ore properties (density,particle size, mineralogy on the dewatering process based on lab and pilot experiments. A hydrocyclonewas used to prepare the required samples for the experiments. To study the effects of mineralogicalproperties, the sedimentation behaviour of hydrocyclone feed and underflow samples were compared. Itwas observed that the free-settling velocity of feed (2 to 6mm/sec was less than in the underflow sample(2 to 7mm/sec and the final concentration of underflow sample (0.45 to 0.48t/m3 was more than thefeed sample (0.44 to 0.47t/m3. Additionally, to study the effects of particle size and density, thesedimentation behaviour of hydrocyclone overflow and feed samples were compared. The settlingvelocity and final concentration of overflow sample were obtained at 0.15 to 0.4mm/sec and 0.32t/m3,respectively, which was significantly less than the feed sample. This was due to the amount of clayreduction in the underflow sample and particle size and density reduction in the overflow sample.Following on, the pilot experiments were carried out. It was observed that the bed formation of the feedsample tended to overflow in the sample at low flux (10t/m2/day and tended to underflow in the sampleat high flux (28.5t/m2/day. This meant that the long time at lower flux created an opportunity for fineparticles to settle easily, similar to coarser particles and as such, ore properties did not play a decisiverole in bed formation, but their effects appeared instead at higher flux. Furthermore, it was observed thatthe underflow concentration increased by decreasing the flux from 28.5 to 10t/m2/day. These increasingamounts were 0.05t/m3 and 0.12t/m3 in hydrocyclone overflow and underflow samples, respectively, at aheight of 2.5 metres. This meant that the compressibility and

  2. High-temperature performance prediction of iron ore fines and the ore-blending programming problem in sintering

    Institute of Scientific and Technical Information of China (English)

    Bing-ji Yan; Jian-liang Zhang; Hong-wei Guo; Ling-kun Chen; Wei Li

    2014-01-01

    The high-temperature performance of iron ore fines is an important factor in optimizing ore blending in sintering. However, the application of linear regression analysis and the linear combination method in most other studies always leads to a large deviation from the desired results. In this study, the fuzzy membership functions of the assimilation ability temperature and the liquid fluidity were proposed based on the fuzzy mathematics theory to construct a model for predicting the high-temperature performance of mixed iron ore. Comparisons of the prediction model and experimental results were presented. The results illustrate that the prediction model is more accurate and effec-tive than previously developed models. In addition, fuzzy constraints for the high-temperature performance of iron ore in this research make the results of ore blending more comparable. A solution for the quantitative calculation as well as the programming of fuzzy constraints is also introduced.

  3. Summary of the mineralogy of the Colorado Plateau uranium ores

    Science.gov (United States)

    Weeks, Alice D.; Coleman, Robert Griffin; Thompson, Mary E.

    1956-01-01

    In the Colorado Plateau uranium has been produced chiefly from very shallow mines in carnotite ores (oxidized vanadiferous uranium ores) until recent deeper mining penetrated black unoxidized ores in water-saturated rocks and extensive exploration has discovered many deposits of low to nonvanadiferous ores. The uranium ores include a wide range from highly vanadiferous and from as much as one percent to a trace of copper, and contain a small amount of iron and traces of lead, zinc, molybdenum, cobalt, nickel, silver, manganese, and other metals. Recent investigation indicates that the carnotite ores have been derived by progressive oxidation of primary (unoxidized) black ores that contain low-valent uranium and vanadium oxides and silicates. The uranium minerals, uraninite and coffinite, are associated with coalified wood or other carbonaceous material. The vanadium minerals, chiefly montroseite, roscoelite, and other vanadium silicates, occur in the interstices of the sandstone and in siltstone and clay pellets as well as associated with fossil wood. Calcite, dolomite, barite and minor amounts of sulfides, arsenides, and selenides occur in the unoxidized ore. Partially oxidized vanadiferous ore is blue black, purplish brown, or greenish black in contrast to the black or dark gray unoxidized ore. Vanadium combines with uranium to form rauvite. The excess vanadium is present in corvusite, fernandinite, melanovanadite and many other quadrivalent and quinquevalent vanadium minerals as well as in vanadium silicates. Pyrite and part or all of the calcite are replaced by iron oxides and gypsum. In oxidized vanadiferous uranium ores the uranium is fixed in the relatively insoluble minerals carnotite and tyuyamunite, and the excess vanadium commonly combines with one or more of the following: calcium, sodium, potassium, magnesium, aluminum, iron, copper, manganese, or barium, or rarely it forms the hydrated pentoxide. The relatively stable vanadium silicates are little

  4. Microporosity of BIF hosted massive hematite ore, Iron Quadrangle, Brazil

    Directory of Open Access Journals (Sweden)

    CÉSAR A.C. VARAJÃO

    2002-03-01

    Full Text Available Massive hematite ore (MHO is a special high-grade iron ore, used as lump ore in the process of obtaining direct reduction iron (DRI. The influence of porosity on the reducibility of MHO from the Capitão do Mato Mine (Iron Quadrangle, Brazil was investigated using optical and scanning electron microscopes on drill core and open pit samples. Hematite is the main component of the samples and occurs as granular crystals (10 mum, microplates (1 mum and euhedral martite (10 to 30 mum. Quartz, maghemite, kenomagnetite and goethite are minor components. Primary micropores (Å to 1 mum are associated with microplaty crystals that fill cavities between granular hematite. Secondary micropores (Å to 5 mum related to euhedral martite crystals, are the most important. The total porosity of weathered samples, measured using nitrogen adsorption and mercury injection, attains values up to 11%, whereas unweathered samples have a porosity less than 2.5%. Reducibility is strongly enhanced by porosity, but inhibited by structure (bedding.O minério de hematita compacta (MHC é um tipo de minério de ferro de alto grau usado como minério granulado na obtenção do ferro via redução direta (DRI. A influência da porosidade sobre a redutibilidade do MHC da Mina de Capitão do Mato (Quadrilátero Ferrífero, Brasil, foi investigada em amostras de furos de sonda e de afloramentos da mina, usando-se microscópio óptico e eletrônico de varredura. Hematita é o principal componente mineralógico e ocorre sob diferentes formas: granular (10 mim, microtabular (1 mim e euédrico (10 a 30 mim. Quartzo maghemita, kenomagnetita e goethita são componetes menores. Microporos primários (Å to 1 mim associam-se a cristais de hematita microtabular, que preenchem espaços entre cristais de hematita granular. Microporos secundários (Å to 5 mim, relacionados com os cristais de martita euédrica, são os mais importantes. A porosidade total das amostras do MHC, medida atrav

  5. Cohesive strength of iron ore granules

    Directory of Open Access Journals (Sweden)

    Contreras Rafael Jaimes

    2017-01-01

    Full Text Available We present an experimental and numerical investigation of the mechanical strength of crude iron ore (Hematite granules in which capillary bonds between primary particles are the source of internal cohesion. The strength is measured by subjecting the granules to vertical compression between two plates. We show that the behavior of the granules is ductile with a well-defined plastic threshold which increases with the amount of water. It is found that the compressive strength scales with capillary cohesion with a pre-factor that is nearly independent of size polydispersity for the investigated range of parameters but increases with friction coefficient between primary particles. This weak dependence may be attributed to the class of fine particles which, due to their large number, behaves as a cohesive matrix that controls the strength of the granule.

  6. Cohesive strength of iron ore granules

    Science.gov (United States)

    Contreras, Rafael Jaimes; Berger, Nicolas; Izard, Edouard; Douce, Jean-François; Koltsov, Alexey; Delenne, Jean-Yves; Azema, Emilien; Nezamabadi, Saeid; van Loo, Frédéric; Pellenq, Roland; Radjai, Farhang

    2017-06-01

    We present an experimental and numerical investigation of the mechanical strength of crude iron ore (Hematite) granules in which capillary bonds between primary particles are the source of internal cohesion. The strength is measured by subjecting the granules to vertical compression between two plates. We show that the behavior of the granules is ductile with a well-defined plastic threshold which increases with the amount of water. It is found that the compressive strength scales with capillary cohesion with a pre-factor that is nearly independent of size polydispersity for the investigated range of parameters but increases with friction coefficient between primary particles. This weak dependence may be attributed to the class of fine particles which, due to their large number, behaves as a cohesive matrix that controls the strength of the granule.

  7. Exact linear modeling using Ore algebras

    CERN Document Server

    Schindelar, Kristina; Zerz, Eva

    2010-01-01

    Linear exact modeling is a problem coming from system identification: Given a set of observed trajectories, the goal is find a model (usually, a system of partial differential and/or difference equations) that explains the data as precisely as possible. The case of operators with constant coefficients is well studied and known in the systems theoretic literature, whereas the operators with varying coefficients were addressed only recently. This question can be tackled either using Gr\\"obner bases for modules over Ore algebras or by following the ideas from differential algebra and computing in commutative rings. In this paper, we present algorithmic methods to compute "most powerful unfalsified models" (MPUM) and their counterparts with variable coefficients (VMPUM) for polynomial and polynomial-exponential signals. We also study the structural properties of the resulting models, discuss computer algebraic techniques behind algorithms and provide several examples.

  8. Improved polynomial remainder sequences for Ore polynomials.

    Science.gov (United States)

    Jaroschek, Maximilian

    2013-11-01

    Polynomial remainder sequences contain the intermediate results of the Euclidean algorithm when applied to (non-)commutative polynomials. The running time of the algorithm is dependent on the size of the coefficients of the remainders. Different ways have been studied to make these as small as possible. The subresultant sequence of two polynomials is a polynomial remainder sequence in which the size of the coefficients is optimal in the generic case, but when taking the input from applications, the coefficients are often larger than necessary. We generalize two improvements of the subresultant sequence to Ore polynomials and derive a new bound for the minimal coefficient size. Our approach also yields a new proof for the results in the commutative case, providing a new point of view on the origin of the extraneous factors of the coefficients.

  9. Rigid Ideals and Radicals of Ore Extensions

    Institute of Scientific and Technical Information of China (English)

    Chan Yong Hong; Tai Keun Kwak; S. Tariq Rizvi

    2005-01-01

    For an endomorphism σ of a ring R, Krempa called σ a rigid endomorphism if aσ(a) = 0 implies a= 0 for a ∈ R. A ring R is called rigid if there exists a rigid endomorphism of R. In this paper, we extend the σ-rigid property of a ring R to an ideal of R. For a σ-ideal Ⅰ of a ring R, we call Ⅰ a σ-rigid ideal if aσ(a) ∈Ⅰ implies a ∈Ⅰ for a ∈ R. We characterize σ-rigid ideals and study related properties. The connections of the prime radical and the upper nil radical of R with the prime radical and the upper nil radical of the Ore extension R[x; σ, δ], respectively, are also investigated.

  10. Super-Enrichment of Dispersed Elements and Associated Ore Deposits

    Institute of Scientific and Technical Information of China (English)

    高振敏; 姚林波

    2004-01-01

    Dispersed elements do not always occur as associated elements in the ore deposits of other elements. Instead, they can constitute independent ore deposits. The focus of this paper is placed on the mechanism of super-enrichment of the four dispersed elements TI, Ge, Se, and Te under favorable geological conditions, where their enrichment coefficients are so high that their abundances can reach n×103-n×104, sometimes even up to n×106 times (e. g. Te) those of the crust. As a result, they can form their independent ore deposits. Studies have shown that such independent ore deposits are mostly distributed in the southwestern part of China, most of which belong to low-temperature ore deposits, ranging in age from Yanshanian to Himalayan(Cretaceous to Cenozoic), with a significant time gap with the host strata. Moreover, this paper also deals with the existing forms (as independent minerals, occurring isomorphously and being adsorbed) of the dispersed elements in those independent ore deposits. The discovery of independent ore deposits of dispersed elements is a great breakthrough in the study of dispersed element metallogenesis.

  11. Leaching hydrodynamics of weathered elution-deposited rare earth ore

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Both porosity (φ) and permeability (k) of the weathered elution-deposited rare earth ores are basic hydrodynamic parameters for RE leaching. The relationship between k and φ of two typical rare earth ores of South China in the packed bed was investigated by measuring the flow (Q) under various leaching pressure difference (Δp). The experimental results show that the relationship between k and φ is unique, moreover the relationship between Q and Δp is in accord with the Darcy's law. The effects of the type of ores, the leaching reagents and its concentration, the granule ore size on the leaching permeability have also been investigated. It is demonstrated that kH (for heavy RE ore, kH=35.98 mm2)>kM-H (for middle-heavy RE ore,kM-H=28.50 mm2), whereas k(NH4NO3)>k(NH4Cl)>k[(NH4)2SO4], and the k value increases with increasing leaching reagents concentration and granule ore size(k0.60~0.75 mm=99.96 mm2,k0.125~0.60 mm=11.83 mm2, k0.074~0.125 mm=0.84 mm2).

  12. Direct Biohydrometallurgical Extraction of Iron from Ore

    Energy Technology Data Exchange (ETDEWEB)

    T.C. Eisele

    2005-10-01

    A completely novel approach to iron extraction was investigated, based on reductive leaching of iron by anaerobic bacteria. Microorganisms were collected from an anaerobic bog where natural seepage of dissolved iron was observed. This mixed culture was used to reduce insoluble iron in a magnetite ore to the soluble ferrous (Fe{sup +2}) state. While dissolution rates were slow, concentrations of dissolved iron as high as 3487 mg/l could be reached if sufficient time was allowed. A factorial study of the effects of trace nutrients and different forms of organic matter indicated that the best dissolution rates and highest dissolved iron concentrations were achieved using soluble carbohydrate (sucrose) as the bacterial food source, and that nutrients other than nitrogen, phosphorus, potassium, sodium, and acetate were not necessary. A key factor in reaching high levels of dissolved iron was maintaining a high level of carbon dioxide in solution, since the solubility of iron carbonates increases markedly as the quantity of dissolved carbon dioxide increases. Once the iron is dissolved, it has been demonstrated that the ferrous iron can then be electroplated from solution, provided that the concentration of iron is sufficiently high and the hydrogen ion concentration is sufficiently low. However, if the leaching solution is electrolyzed directly, organic matter precipitates at the cathode along with the metallic iron. To prevent this problem, the ferrous iron should be separated from the bulk solution in a more concentrated, purified form. One route to accomplishing this is to take advantage of the change in solubility of ferrous iron as a function of carbon dioxide concentration. By cycling the concentration of carbon dioxide in solution, it is possible to produce an iron-rich concentrate that should be suitable for electrolysis. This represents the first viable hydrometallurgical method for leaching iron directly from ore and producing metallic iron.

  13. Correlation analysis on partition of rare earth in ion-exchangeable phase from weathered crust ores

    Institute of Scientific and Technical Information of China (English)

    CHI Ru-an; DAI Zu-xu; XU Zhi-gao; WU Yuan-xin; WANG Cun-wen

    2006-01-01

    The rare earth(RE) in weathered crust ores mainly exists as ion-exchangeable phase, approximately 80%. The correlation analysis on partition of 376 samples in ion-exchangeable phase from weathered crust ores was conducted. The results show that partition both among heavy RE elements and light RE elements with high partition appears positive correlation, but partition sums between the heavy RE elements and the light RE elements appear close negative correlation obviously. Clear negative correlations exist between the light RE elements (except Ce) and yttrium(Y). Matrix of correlation analysis on this partition can be divided into three zones. The correlated coefficient variation from negative to positive in zones B and C occurs at Gd, so does that in zones B and A (except Ce, Eu, and Sm), suggesting that RE elements can be divided into two groups with Gd as border. This phenomenon is called Gadolinium-broken effect.

  14. An Application of Microwave Pre-oxidation in Improving Gold Recovery of a Refractory Gold Ore

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Microwave radiation was employed as a pretreating technology to oxidise a refractory gold ore. Heating characteristics showed that, in an identical microwave field, the bulk temperature of the sample increased with microwave power, microwave radiation time and particle size. The rate of sulphur removal increased with microwave radiation time. Particle size also had a significant effect on the oxidation rate. Pyrite and marcasite could be oxidised into Fe2O3 with a high porous structure. When microwave radiation was carried out in a rotary bed, the oxidation was more uniformly developed, in comparison with in a fixed bed. Gold extraction by cyanidation could be remarkably improved after the ore was subjected to microwave radiation. The results showed that gold recovery could be improved from 37% to 69%~81.2%.

  15. Laboratory Study on the Removal of Fluorine from High Fluorine Bearing Zinc Oxide Ore

    Institute of Scientific and Technical Information of China (English)

    Yaozhong LAN; Liaoyuan YE; Rose W. Smith

    2005-01-01

    An ever increasing demand for zinc has resulted in worldwide efforts to exploit complex and lean grade reserves of zinc oxide ore. In this study experiments were done on zinc recovery from high-fluorine bearing zinc oxide ore. First the effect of different variables on fluorine removal was investigated. Optimum experimental conditions occurred when the temperature was 1173 K, roasting time was 90 min and air flow was at a velocity of 5 m/min, the fluorine removal from the samples reached over 93%. The results obtained indicate that fluorine removal is not enhanced by adding diluted sulfuric acid or water as a binder. Second the roasted materials were leached with a diluted sulfuric acid,neutralized, flocculated and filtrated. The residual fluorine content in the leached solutions was less than 38 mg/L,which satisfies the requirement of fluorine content in the leached solutions for the production of electrolytic zinc.

  16. Kinetics and thermodynamics of the attack of a phosphate ore by acid solutions at different temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Antar, K. [Faculty of Science of Tunis, Chemistry Department, Applied Thermodynamics Laboratory, 2092 Tunis El Manar (Tunisia); Jemal, M. [Faculty of Science of Tunis, Chemistry Department, Applied Thermodynamics Laboratory, 2092 Tunis El Manar (Tunisia)], E-mail: jemal@planet.tn

    2008-08-15

    A calorimetric study of the kinetics and thermodynamics of the attack of a phosphate ore from Gafsa region (Tunisia) by phosphoric acid and by a mixture of phosphoric acid and sulfuric acids is undertaken at different temperatures. Two samples of the same ore having different grain size have been used. At 25 deg. C, the dissolution enthalpy in phosphoric acid solution equals -233.6 {+-} 2.2 J/g for both of the samples. Attack by the mixture of acids is strongly dependent on the solid granulometry. Interpretation of the calorimetric results by Avrami model shows the existence of three domains attributed to phosphate ore dissolution/H{sub 2}PO{sub 4}{sup -} neutralisation, hemihydrate (HH) precipitation and hemihydrate/dihydrate (DH) transformation. The attack by the acid mixture was performed at higher temperatures and showed in addition the transitional formation of the anhydrous sulfate (AH) at T {>=} 55 deg. C, which transforms into dihydrate after the HH/DH transformation.

  17. Sulfur isotope geochemistry of ore and gangue minerals from the Silesian-Cracow Mississippi Valley-type ore district, Poland

    Science.gov (United States)

    Leach, D.L.; Vets, J.G.; Gent, C.A.

    1996-01-01

    Studies of the sulfur isotopic composition of ore and gangue minerals from the Silesian-Cracow Zn-Pb district were conducted to gain insights into processes that controlled the location and distribution of the ore deposits. Results of this study show that minerals from the Silesian-Cracow ore district have the largest range of sulfur isotope compositions in sulfides observed from any Mississippi Valley-type ore district in the world. The ??34S values for sulfide minerals range from +38 to -32 per mil for the entire paragenetic sequence but individual stages exhibit smaller ranges. There is a well developed correlation between the sulfur isotope composition and paragenetic stage of ore deposition. The first important ore stage contains mostly positive ??34S values, around 5 per mil. The second stage of ore formation are lower, with a median value of around -5 to -15 per mil, and with some values as low as -32 per mil. Late stage barite contains isotopically heavy sulfur around +32 per mil. The range in sulfur isotope compositions can be explained by contributions of sulfur from a variety of source rocks together with sulfur isotope fractionations produced by the reaction paths for sulfate reduction. Much of the variation in sulfur isotope compositions can be explained by bacterial reduction of sedimentary sulfate and disequilibrium reactions by intermediate-valency sulfur species, especially in the late-stage pyrite and sphalerite. Organic reduction of sulfate and thermal release of sulfur from coals in the Upper Silesian Coal Basin may have been important contributors to sulfur in the ore minerals. The sulfur isotopic data, ore mineral textures, and fluid inclusion data, are consistent with the hypothesis that fluid mixing was the dominant ore forming mechanism. The rather distinct lowering of ?? 34S values in sulfides from stage 2 to stage 3 is believed to reflect some fundamental change in the source of reduced sulfur and/or hydrology of the ore

  18. Lead Isotope Constraints on the Sources of Ore Metals in SW Mexican Deposits

    Science.gov (United States)

    Potra, A.; Macfarlane, A. W.

    2007-12-01

    Lead isotope ratios from mineral deposits in southern Mexico increase with distance from the trench from 206Pb/204Pb values between 18.597 and 18.650 in the coastal area to values between 18.712 and 19.069 approximately 800 km east from the trench. This variation has been attributed to increasing assimilation of radiogenic lead from the crust with increasing distance from the trench. New sampling was undertaken in this area to provide a clearer picture of the potential sources of ore metals in this arc system, and also, if possible, to examine whether ore metal sources differ among the proposed tectonostratigraphic exotic terranes of southern Mexico. New TIMS lead isotope analyses are presented for samples from the metamorphic basement rocks of the Guerrero Terrane, the Late Cretaceous clastic sedimentary rocks from the Upper Mesozoic Assemblage, and for mid-Cretaceous igneous rocks, as well as for samples from the Oligocene La Verde, Esmeralda, and El Malacate copper prospects. Whole rock samples of schist from the Jurassic-Cretaceous Arteaga Complex and phyllite and slate from the Tierra Caliente Complex contain radiogenic lead relative to bulk earth models, with 206Pb/204Pb ranging from 18.981-19.256. These values are substantially more radiogenic than published values of analyses of metagabbro and charnockite from the Grenvillian-age Oaxaca Terrane. Sedimentary rocks (sandstones, siltstones, and marls) belonging to the Huetamo Sequence have 206Pb/204Pb values ranging between 18.630 to 18.998, close to the published data for the sediments from IPOD-DSDP Sites 487 and 488, Cocos Plate. Whole rock analyses of igneous rocks (granodiorite) collected from La Verde and El Malacate have 206Pb/204Pb ranging from 18.764 to 18.989, clustering between the fields represented by the sedimentary and the metamorphic rocks, suggesting assimilation of lead from these components. Ore samples from La Verde and Esmeralda have 206Pb/204Pb between 18.685 and 18.731 and plot within

  19. Assessment of natural radioactivity in aquifer medium bearing uranium ores in Koprubasi, Turkey

    Science.gov (United States)

    Simsek, Celalettin

    2008-10-01

    Koprubasi, located within Manisa Province near the Izmir, is the biggest uranium mine where uranium ores originate from Neogene aged altered sandstone and conglomerate layers. The main objective of this study is to determine the radiation hazard associated with radioactivity levels of uranium ores, and the rocks and sediments around Koprubasi. In this regard, measured activity levels of 226Ra, 232Th and 40K were compared with world averages. The average activity levels of 226 Ra, 232Th and 40K were measured to be 5369.75, 124.78 and 10.0 Bq/kg in uranium ores, 24.32, 52.94 and 623.38 Bq/kg in gneiss, 46.24, 45.13 and 762.26 Bq/kg in sandstone and conglomerate, 73.11, 43.15 and 810.65 Bq/kg in sediments, respectively. All samples have high 226Ra and 40K levels according to world average level. As these sediments are used as construction materials and in agricultural activities within the study area, the radiation hazard are calculated by using dose rate (D), annual effective dose rate (He), radium equivalent activity (Raeq) and radiation hazard index (Iyr). All the samples have Raeq levels that are lower than the world average limit of 370 Bq/kg. On the other hand, D, He and Iyr values are higher than world average values. These results indicate that the uranium ores in the Koprubasi is the most important contributor to the natural radiation level. The radioactivity levels of sediments and rocks make them unsuitable for use as agricultural soil and as construction materials. Moreover, it is determined that shallow groundwater in sediments and deep groundwater in conglomerate rocks and also surface water sources in the Koprubasi have high 226Ra content. According to environmental radioactive baseline, some environmental protection study must be taken in Koprubasi uranium site and the environment.

  20. Water leaching of titanium from ore flotation residue.

    Science.gov (United States)

    Jaworska, Malgorzata M; Guibal, Eric

    2003-01-01

    Copper ore tailings were tested for the stability of titanium submitted to water leaching in three different reactor systems (agitated vessel, bioreactor and percolated fixed-bed column). For each of these systems, titanium extraction did not exceed 1% of the available metal. Biomass removed from ore residue adsorbed a small part of the titanium with sorption capacities below 20-30 mg g(-1), but most of this biomass was sequestered in the ore residue. Oxygen and carbon dioxide concentrations were monitored and changes in concentration correlated with bacteria development at the initial stage of the process and to fungal development in the latter stages.

  1. Microstructure of Bentonite in Iron Ore Green Pellets

    OpenAIRE

    Bhuiyan, Iftekhar U.; Mouzon, Johanne; Schröppel, Birgit; Kaech, Andres; Dobryden, Illia; Forsmo, Seija P.E.; Hedlund, Jonas

    2017-01-01

    Sodium-activated calcium bentonite is used as a binder in iron ore pellets and is known to increase strength of both wet and dry iron ore green pellets. In this article, the microstructure of bentonite in magnetite pellets is revealed for the first time using scanning electron microscopy. The microstructure of bentonite in wet and dry iron ore pellets, as well as in distilled water, was imaged by various imaging techniques (e.g., imaging at low voltage with monochromatic and decelerated beam ...

  2. Biological-Chemical Oxidation of Ore Minerals at Pezinok Deposit

    Directory of Open Access Journals (Sweden)

    Martin Chovan

    2004-12-01

    Full Text Available The article presents results of leaching experiments of the comparison between chemical and biological-chemical leaching, at the same conditions in solution, of ores from the Sb-(Au- base metal deposit Pezinok (Malé Karpaty Mts., Western Carpathians, Slovakia. The research study shows the oxidation order and the progression of present ore minerals (löllingite, arsenopyrite, stibnite, native Sb, gudmundite, berthierite, pyrite, sphalerite and chalcopyrite. There are discussed differences between chemical and biological-chemical leaching activity of various ore minerals at the surface of polished sections. The extent of the leaching of sulphide minerals is significantly higher than that without bacteria.

  3. Tourmaline as a recorder of ore-forming processes

    Science.gov (United States)

    Slack, J.F.; Trumbull, R.B.

    2011-01-01

    Tourmaline occurs in diverse types of hydrothermal mineral deposits and can be used to constrain the nature and evolution of ore-forming fl uids. Because of its broad range in composition and retention of chemical and isotopic signatures, tourmaline may be the only robust recorder of original mineralizing processes in some deposits. Microtextures and in situ analysis of compositional and isotopic variations in ore-related tourmaline provide valuable insights into hydrothermal systems in seafl oor, sedimentary, magmatic, and metamorphic environments. Deciphering the hydrothermal record in tourmaline also holds promise for aiding exploration programs in the search for new ore deposits.

  4. Start of exploration and mining of uranium ores in Hungary

    Energy Technology Data Exchange (ETDEWEB)

    Mikolay, I.; Szomolanyi, G. (Mecseki Ercbanyaszati Vallalat, Pecs II (Hungary))

    1983-09-01

    The mining of uranium ores is the youngest branch in the history of the Hungarian ore mining. The exploration for uranium ores started in Hungary in the decade from 1947, using simple methods at the beginning to apply more developed technologies later on. From the year 1952 Soviet geologists and geophysicists joined the explorations using the most advanced instruments, in co-operation with the Hungarian experts. From 1953 explorations and developments have been concentrated on the SW area of Mountain Mecsek so that by 1957 the preliminary conditions of a successful Hungarian uranium mining were established.

  5. Organic Gases in Fluid Inclusions of Ore Minerals and Their Constraints on Ore Genesis: A Case Study of the Changkeng Au-Ag Deposit, Guangdong, China

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The newly discovered Changkeng Au-Ag deposit is a new type of sediment-hosted precious metal deposit. Most of the previous researchers believed that the deposit was formed by meteoric water convection. By using a high vacuum quadrupole gas mass spectrometric system, nine light hydrocarbons have been recognized in the fluid inclusions in ore minerals collected from the Changkeng deposit. The hydrocarbons are composed mainly of saturated alkanes C1-4 and unsaturated alkenes C2-4 and aromatic hydrocarbons, in which the alkanes are predominant, while the contents of alkenes and aromatic hydrocarbons are very low. The Σalka/Σalke ratio of most samples is higher than 100, suggesting that those hydrocarbons are mainly generated by pyrolysis of kerogens in sedimentary rocks caused by water-rock interactions at medium-low temperatures, and the metallogenic processes might have not been affected by magmatic activity. A thermodynamic calculation shows that the light hydrocarbons have reached chemical equilibrium at temperatures higher than 200?C, and they may have been generated in the deep part of sedimentary basins (e.g., the Sanzhou basin) and then be transported by ore-forming fluids to a shallow position of the basin via a long distance. Most of the organic gases are generated by pyrolysis of the type II kerogens (kukersite) in sedimentary host rocks, only a few by microorganism activity. The compositions and various parameters of light hydrocarbons in gold ores are quite similar to those in silver ores, suggesting that the gold and silver ores may have similar metallogenic processes. Based on the compositions of organic gases in fluid inclusions, the authors infer that the Changkeng deposit may be of a tectonic setting of continental rift. The results of this study support from one aspect the authors' opinion that the Changkeng deposit is not formed by meteoric water convection, and that its genesis has a close relationship with the evolution of the Sanzhou basin, so

  6. 40 CFR 440.90 - Applicability; description of the antimony ore subcategory.

    Science.gov (United States)

    2010-07-01

    ... antimony ore subcategory. 440.90 Section 440.90 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Antimony Ore Subcategory § 440.90 Applicability; description of the antimony ore subcategory. The provisions of...

  7. 40 CFR 440.20 - Applicability; description of the aluminum ore subcategory.

    Science.gov (United States)

    2010-07-01

    ... aluminum ore subcategory. 440.20 Section 440.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Aluminum Ore Subcategory § 440.20 Applicability; description of the aluminum ore subcategory. The provisions of...

  8. 40 CFR 440.50 - Applicability; description of the titanium ore subcategory.

    Science.gov (United States)

    2010-07-01

    ... titanium ore subcategory. 440.50 Section 440.50 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Titanium Ore Subcategory § 440.50 Applicability; description of the titanium ore subcategory. The provisions of...

  9. 40 CFR 440.70 - Applicability; description of the nickel ore subcategory.

    Science.gov (United States)

    2010-07-01

    ... nickel ore subcategory. 440.70 Section 440.70 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Nickel Ore Subcategory § 440.70 Applicability; description of the nickel ore subcategory. The provisions of this...

  10. 40 CFR 440.40 - Applicability; description of the mercury ore subcategory.

    Science.gov (United States)

    2010-07-01

    ... mercury ore subcategory. 440.40 Section 440.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Mercury Ore Subcategory § 440.40 Applicability; description of the mercury ore subcategory. The provisions of subpart...

  11. 40 CFR 440.110 - Applicability; description of the platinum ore subcategory.

    Science.gov (United States)

    2010-07-01

    ... platinum ore subcategory. 440.110 Section 440.110 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Platinum Ores Subcategory § 440.110 Applicability; description of the platinum ore subcategory. The provisions of...

  12. 40 CFR 440.60 - Applicability; description of the tungsten ore subcategory.

    Science.gov (United States)

    2010-07-01

    ... tungsten ore subcategory. 440.60 Section 440.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Tungsten Ore Subcategory § 440.60 Applicability; description of the tungsten ore subcategory. The provisions of...

  13. Geochemistry of Rare Earth Elements in Xikeng Ag-Pb-Zn Ore Deposit, South Anhui, China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper, a comparative study is done on the geochemical charateristics of REE in ore, ore-hosted rocks of Lantian group, granite related to ore deposit, and altered rocks for tracing origin of ore-forming materials. The result indicates that the ore-forming fluid and ore-forming materials for Xikeng silver-polymetallic ore deposit were derived from Yixian granite's magmatic activity. Water-rock reaction of the hydrothermal fluid with the carbonate-rich stratum led the altered rock to relatively enrich in HREE.

  14. Studies on Sulfating Roasting Process for Mianning Bastnasite and Baotou Mixed RE Concentrate Ore

    Institute of Scientific and Technical Information of China (English)

    Miao Guangli

    2004-01-01

    Some processes of sulfating roasting and water leaching of crude Mianning RE concentrate ore, of fine Mianning RE concentrate ore, of Baotou RE concentrate ore and of their mixture were investigated.The result shows that the mixture of Mianning and Baotou RE concentrate ore has the optimum leaching rate and rate of recovery when the mixture ratio is 1:4.The recovery rate of the mixture is higher by 14.76% than that of crude Mianning RE concentrate ore, by 5.0 % than that of Mianning fine RE concentrate ore and by 2.4 % than that of Baotou RE concentrate ore.

  15. Experimental study on preferential solution flow during dump leaching of low-grade ores

    Institute of Scientific and Technical Information of China (English)

    YIN Sheng-hua; WU Ai-xiang; SU Yong-ding; ZHANG Jie

    2007-01-01

    The phenomenon of preferential solution flow during dump leaching of low-grade ores was studied. The formative mechanism of preferential solution flow was investigated through analyzing the relationship between permeability and ore diameter,and the relationship between surface tension and ore diameter. The preferential solution flow happened within the fine ore area when the dump was unsaturated. And it could happen within the coarse ore area when the dump became saturated. The results of experiment show that the outflow of coarse ore area increases sharply with higher applied rate. The outflow of fine ore area is greater than that of coarse ore area when the applied rate is below 3.2 L/min, and the preferential solution flow happens in fine ore area. But the preferential solution flow happens in coarse ore area when the applied rate is higher than 3.2 L/min. The result of the experiment is consistent with the mechanism analyzing.

  16. Arsenic bioleaching in medical realgar ore and arsenic- bearing ...

    African Journals Online (AJOL)

    medical realgar ore that allowed much higher leaching rates ... bioleaching behavior between mixed unadapted ... Acid drainage from copper mine, Zhongtiao Mountain, Shanxi,. China ..... during high temperature bioleaching of gold-bearing.

  17. Microstructure of bentonite in iron ore green pellets.

    Science.gov (United States)

    Bhuiyan, Iftekhar U; Mouzon, Johanne; Schröppel, Birgit; Kaech, Andres; Dobryden, Illia; Forsmo, Seija P E; Hedlund, Jonas

    2014-02-01

    Sodium-activated calcium bentonite is used as a binder in iron ore pellets and is known to increase strength of both wet and dry iron ore green pellets. In this article, the microstructure of bentonite in magnetite pellets is revealed for the first time using scanning electron microscopy. The microstructure of bentonite in wet and dry iron ore pellets, as well as in distilled water, was imaged by various imaging techniques (e.g., imaging at low voltage with monochromatic and decelerated beam or low loss backscattered electrons) and cryogenic methods (i.e., high pressure freezing and plunge freezing in liquid ethane). In wet iron ore green pellets, clay tactoids (stacks of parallel primary clay platelets) were very well dispersed and formed a voluminous network occupying the space available between mineral particles. When the pellet was dried, bentonite was drawn to the contact points between the particles and formed solid bridges, which impart strength to the solid compact.

  18. Carbothermal Upgrading of the Awaso Bauxite Ore using Waste ...

    African Journals Online (AJOL)

    Michael

    2015-06-01

    Jun 1, 2015 ... Ore using Waste Pure Water Sachets as Reductant”, Ghana Mining Journal, Vol. ... content) and the emergence of low grade bauxite with high iron oxide content calls for ... effects on the alumina extraction process (Lu et al.,.

  19. ENVIRONMENTAL ISSUE IN COPPER ORE FLOTATION BY XANTHATES

    National Research Council Canada - National Science Library

    Zoran Markovic

    2015-01-01

      This paper presents some investigation results about potassium ethyl xanthate (PEX) stability in water solution at higher pH and in presence of mineral chalcopyrite, related to flotation of copper minerals from copper ore...

  20. Measurement and Modelling of Blast Movement to Reduce Ore ...

    African Journals Online (AJOL)

    user

    growth both from new discoveries and the develop- ment of Subika ... search have developed innovative tools and tech- niques to .... 7 Histogram of Horizontal Blast Displace ment from All Five .... Better QA/QC along the ore/waste boundaries.

  1. By lithology Zbruch deposits (Lower Sarmatian Nikopol manganese ore Basin

    Directory of Open Access Journals (Sweden)

    Bogdanovich V.V.

    2010-06-01

    Full Text Available Based on lithologic-paleogeographic study Zbruch layers of Nikopol manganese ore Basin sediments described lithological and genetic types of rocks and facies conditions of formation of deposits.

  2. Helium-argon isotopic tracing for the Pb-Zn-Ag polymetallic ore deposits in the central-south segment of the Da Hinggan Ling Range

    Institute of Scientific and Technical Information of China (English)

    WANG Baode; NIU Shuyin; SUN Aiqun; HU Huabin; LIU Yaming; GUO Lijun; WANG Shuo

    2008-01-01

    In recent years big strides have been made in the exploration of ores in the central-south segment of the Da Hinggan Ling Range, though some debates still exist on the metallogenesis and sources of ore-forming materials.Pyrite and other sulfides in direct relation to the Pb-Zn-Ag ore deposits were chosen for the He and Ar isotopic analysis of ore-forming fluids, and the first He and Ar isotope data have been obtained from the study region.3He/4He ratios in 14 samples collected from 7 mining districts are 2.17x10-6-12.52×10-6, averaging 6.86×10-6 and their R/Ra ratios are 1.56-9.01 Ra, averaging 4.37 Ra. By projecting the data points onto the 3He-4He concentrations diagram, all the points fall near the mantle helium area. The calculated mantle-source helium ratios are within the range of 19.58%-76.96%, with an average of 49.52%. Argon isotopic characteristics are close to those of mantle source, indicating that the ore-forming material was transport upwards via the multi-stage evolution of mantle plume and concentrated as ores in the favorable loci of mantle branch structures.

  3. Paleomagnetic dating of non-sulfide Zn-Pb ores in SW Sardinia (Italy: a first attempt

    Directory of Open Access Journals (Sweden)

    L. Sagnotti

    2005-06-01

    Full Text Available A first paleomagnetic investigation aimed at constraining the age of the non-sulfide Zn-Pb ore deposits in the Iglesiente district (SW Sardinia, Italy was carried out. In these ores, the oxidation of primary sulfides, hosted in Cambrian carbonate rocks, was related to several paleoweathering episodes spanning from the Mesozoic onward. Paleomagnetic analyses were performed on 43 cores from 4 different localities, containing: a non-oxidized primary sulfides and host rock, b oxidized Fe-rich hydrothermal dolomites and (c supergene oxidation ore («Calamine». Reliable data were obtained from 18 samples; the others show uninterpretable results due to low magnetic intensity or to scattered demagnetization trajectories. Three of them show a scattered Characteristic Remanent Magnetization (ChRM, likely carried by the original (i.e. Paleozoic magnetic iron sulfides. The remaining 15 samples show a well defined and coherent ChRM, carried by high-coercivity minerals, acquired after the last phase of counterclockwise rotation of Sardinia (that is after 16 Myr, in a time interval long enough to span at least one reversal of the geomagnetic field. Hematite is the main magnetic carrier in the limestone, whereas weathered hydrothermal dolomite contains goethite or a mixture of both. The results suggest that paleomagnetism can be used to constrain the timing of oxidation in supergene-enriched ores.

  4. Iron ore industry emissions as a potential ecological risk factor for tropical coastal vegetation.

    Science.gov (United States)

    Kuki, Kacilda N; Oliva, Marco A; Pereira, Eduardo G

    2008-07-01

    In the coastal zone of the Espírito Santo state, Brazil, fragments of restinga, which form a natural ecosystem, share their space with an increasing number of iron ore industries. The iron ore dust and SO(2) originating from the industry processing activities can interfere with the vegetation of the adjacent ecosystems at various levels. This study was undertaken in order to evaluate the effects of industry emissions on representative members of the restinga flora, by measuring physiological and phenological parameters. Foliar samples of Ipomoea pes caprae, Canavalia rosea, Sophora tomentosa, and Schinus terebinthifolius were collected at three increasing distances from an ore industry (1.0, 5.0, and 15.0 km), and were assessed for their dust deposition, chlorophyll, and Fe content. Phenological monitoring was focused on the formation of shoots, flowers, and fruits and was also performed throughout the course of a year. The results showed that the edaphic characteristics and the mineral constitutions of the plants were affected by industry emissions. In addition, the chlorophyll content of the four species increased with proximity to the industry. Phenological data revealed that the reproductive effort, as measured by fruit production, was affected by emissions and S. tomentosa was the most affected species. The use of an integrative approach that combines biochemical and ecological data indicates that the restinga flora is under stress due to industry emissions, which on a long-term basis may put the ecosystem at risk.

  5. Effect of Tourmaline-Doped on the Far Infrared Emission of Iron Ore Tailings Ceramics.

    Science.gov (United States)

    Liu, Jie; Meng, Junping; Liang, Jinsheng; Zhang, Hongchen; Gu, Xiaoyang

    2016-04-01

    Iron ore tailings as secondary resources have been of great importance to many countries in the world. Their compositions are similar to that of infrared emission ceramics, but there are few reports about it. In addition, tourmaline has high infrared emission properties due to its unique structure. With the purpose of expanding functional utilization of iron ore tailings, as well as reducing the production cost of far infrared ceramics, a new kind of far infrared emission ceramics was prepared by using iron ore tailings, calcium carbonate, silica, and natural tourmaline. The ceramics powders were characterized by Fourier transform infrared spectroscope, X-ray diffraction and scanning electron microscopy, respectively. The results show that after being sintered at 1065 °C, the percentage of pseudobrookite and lattice strain of samples increased with increasing the elbaite content. Furthermore, the added tourmaline was conducive to the densification sintering of ceramics. The appearance of Li-O vibration at 734.73 cm-1, as well as the strengthened Fe-O vibration at 987.68 cm-1 were attributed to the formation of Li0.375Fe1.23Ti1.4O5 solid solution, which led the average far infrared emissivity of ceramics increase from 0.861 to 0.906 within 8-14 µm.

  6. Influence of flotation cell volume and solids mass on kinetics of sulfide ore flotation

    Directory of Open Access Journals (Sweden)

    Plawski Michal

    2016-01-01

    Full Text Available The paper presents studies on the influence of flotation cell capacity and mass of solids in the suspension on the flotation kinetics of sulfide copper ore. A sample of copper ore that was collected from the Polkowice Mine of KGHM Polska Miedz S.A. in Poland was used in the experiments. It was determined that neither the volume of flotation cell nor the mass of solids had influence on the type of kinetics equation of flotation. Copper-bearing minerals floated according to the second-order equation, while the remaining components according to the first-order equation. The kinetic rate constants and maximum recovery of the studied components decreased with increasing solids mass in the flotation cell, regardless of the capacity of the cell. The best results were obtained for tests using a 1.0 dm3 cell, while the less favorable kinetics results were observed in the test with the smallest cell of 0.75 dm3 volume. The obtained results can be helpful in choosing the most appropriate methodology of upgrading the sulfide copper ore from Poland in order to obtain the best kinetics results.

  7. Experimental evaluation of sorptive removal of fluoride from drinking water using iron ore

    Science.gov (United States)

    Kebede, Beekam; Beyene, Abebe; Fufa, Fekadu; Megersa, Moa; Behm, Michael

    2016-03-01

    High concentrations of fluoride in drinking water is a public health concern globally and of critical importance in the Rift Valley region. As a low-cost water treatment option, the defluoridation capacity of locally available iron ore was investigated. Residence time, pH, agitation rate, particle size of the adsorbent, sorbent dose, initial fluoride concentration and the effect of co-existing anions were assessed. The sorption kinetics was found to follow pseudo-first-order rate and the experimental equilibrium sorption data fitted reasonably well to the Freundlich model. The sorption capacity of iron ore for fluoride was 1.72 mg/g and the equilibrium was attained after 120 min at the optimum pH of 6. The sorption study was also carried out at natural pH conditions using natural ground water samples and the fluoride level was reduced from 14.22 to 1.17 mg/L (below the WHO maximum permissible limit). Overall, we concluded that iron ore can be used in water treatment for fluoride removal in the Rift Valley region and beyond.

  8. Fission track evidence on thermal history of Jiama polymetallic ore district, Tibet

    Institute of Scientific and Technical Information of China (English)

    袁万明; 侯增谦; 李胜荣; 王世成

    2001-01-01

    It is a new attempt to study thermal evolution related to mineralization using the fission track (FT) method. Apatite and zircon fission track data are reported for 6 samples collected from Jiama ore district as well as its periphery. The FT ages of apatites in the ore district are (16.1±0.9) Ma and (18.8±1.1) Ma and reflect the age of late period of hydrothermal mineralizing event. Apatite FT age of (22.0±4.3) Ma and zircon FT age of (20.9±2.0) Ma are related to the early period of mineralization. Another zircon FT age of (341.6±79.1) Ma, inheriting mineral source characteristic, has no connection with the mineralization. Based on the thermal history analysis, the mineralization began before 25-22 Ma. Cooling rate in the ore district is 5-6℃/Ma averagely, in which a slow cooling occurred at 90-80℃. About 2.7 km has been denuded and the denudation rate is higher than the uplifting rate.

  9. Dielectric behaviour of MgFe2O4 prepared from chemically beneficiated iron ore rejects

    Indian Academy of Sciences (India)

    K S Rane; V M S Verenkar; P Y Sawant

    2001-06-01

    Chemically beneficiated high silica/alumina iron ore rejects (27–76% Fe2O3) were used to synthesize iron oxides of purity 96–98% with SiO2/Al2O3 ratio reduced to 0.03. The major impurities on chemical beneficiations were Al, Si, and Mn in the range 2–3%. A 99.73% purity Fe2O3 was also prepared by solvent extraction method using methyl isobutyl ketone (MIBK) from the acid extracts of the ore rejects. The magnesium ferrite, MgFe2O4, prepared from these synthetic iron oxides showed high resistivity of ∼ 108 ohm cm. All ferrites showed saturation magnetization, 4s, in the narrow range of 900–1200 Gauss and the Curie temperature, c, of all these fell within a small limit of 670 ± 30 K. All ferrites had low dielectric constants ('), 12–15, and low dielectric loss, tan , which decreased with the increase in frequency indicating a normal dielectric dispersion found in ferrites. The presence of insignificant amount of polarizable Fe2+ ions can be attributed to their high resistances and low dielectric constants. Impurities inherent in the samples had no marked influence on the electrical properties of the ferrites prepared from the iron ore rejects, suggesting the possibility of formation of ferrite of constant composition, MgFe2O4, of low magnetic and dielectric losses at lower temperatures of 1000°C by ceramic technique.

  10. Pre-colombian mercury pollution associated with the smelting of argentiferous ores in the Bolivian Andes.

    Science.gov (United States)

    Cooke, Colin A; Balcom, Prentiss H; Kerfoot, Charles; Abbott, Mark B; Wolfe, Alexander P

    2011-02-01

    The development of the mercury (Hg) amalgamation process in the mid-sixteenth century triggered the onset of large-scale Hg mining in both the Old and New Worlds. However, ancient Hg emissions associated with amalgamation and earlier mining efforts remain poorly constrained. Using a geochemical time-series generated from lake sediments near Cerro Rico de Potosí, once the world's largest silver deposit, we demonstrate that pre-Colonial smelting of Andean silver ores generated substantial Hg emissions as early as the twelfth century. Peak sediment Hg concentrations and fluxes are associated with smelting and exceed background values by approximately 20-fold and 22-fold, respectively. The sediment inventory of this early Hg pollution more than doubles that associated with extensive amalgamation following Spanish control of the mine (1574-1900 AD). Global measurements of [Hg] from economic ores sampled world-wide indicate that the phenomenon of Hg enrichment in non-ferrous ores is widespread. The results presented here imply that indigenous smelting constitutes a previously unrecognized source of early Hg pollution, given naturally elevated [Hg] in economic silver deposits.

  11. Study of nonisothermal reduction of iron ore-coal/char composite pellet

    Science.gov (United States)

    Dutta, S. K.; Ghosh, A.

    1994-01-01

    Cold-bonded composite pellets, consisting of iron ore fines and fines of noncoking coal or char, were prepared by steam curing at high pressure in an autoclave employing inorganic binders. Dry compressive strength ranged from 200 to 1000 N for different pellets. The pellets were heated from room temperature to 1273 K under flowing argon at two heating rates. Rates of evolution of product gases were determined from gas Chromatographie analysis, and the temperature of the sample was monitored by thermocouple as a function of time during heating. Degree of reduction, volume change, and compressive strength of the pellets upon reduction were measured subsequently. Degree of reduction ranged from 46 to 99 pct. Nonisothermal devolatilization of coal by this procedure also was carried out for comparison. It has been shown that a significant quantity (10 to 20 pct of the pellet weight) of extraneous H2O and CO2 was retained by dried pellets. This accounted for the generation of additional quantities of H2 and CO during heating. Carbon was the major reductant, but reduction by H2 also was significant. Ore-coal and ore-char composites exhibited a comparable degree of reduction. However, the former showed superior postreduction strength due to a smaller amount of swelling upon reduction.

  12. Geochemical Fingerprinting of Coltan Ores by Machine Learning on Uneven Datasets

    Energy Technology Data Exchange (ETDEWEB)

    Savu-Krohn, Christian, E-mail: christian.savu-krohn@unileoben.ac.at; Rantitsch, Gerd, E-mail: gerd.rantitsch@unileoben.ac.at [Montanuniversitaet Leoben, Department of Applied Geosciences and Geophysics (Austria); Auer, Peter, E-mail: auer@unileoben.ac.at [Chair for Information Technology, Montanuniversitaet Leoben (Austria); Melcher, Frank, E-mail: frank.melcher@bgr.de; Graupner, Torsten, E-mail: torsten.graupner@bgr.de [Federal Institute for Geosciences and Natural Resources (Germany)

    2011-09-15

    Two modern machine learning techniques, Linear Programming Boosting (LPBoost) and Support Vector Machines (SVMs), are introduced and applied to a geochemical dataset of niobium-tantalum ('coltan') ores from Central Africa to demonstrate how such information may be used to distinguish ore provenance, i.e., place of origin. The compositional data used include uni- and multivariate outliers and elemental distributions are not described by parametric frequency distribution functions. The 'soft margin' techniques of LPBoost and SVMs can be applied to such data. Optimization of their learning parameters results in an average accuracy of up to c. 92%, if spot measurements are assessed to estimate the provenance of ore samples originating from two geographically defined source areas. A parameterized performance measure, together with common methods for its optimization, was evaluated to account for the presence of uneven datasets. Optimization of the classification function threshold improves the performance, as class importance is shifted towards one of those classes. For this dataset, the average performance of the SVMs is significantly better compared to that of LPBoost.

  13. Iron Ore Industry Emissions as a Potential Ecological Risk Factor for Tropical Coastal Vegetation

    Science.gov (United States)

    Kuki, Kacilda N.; Oliva, Marco A.; Pereira, Eduardo G.

    2008-07-01

    In the coastal zone of the Espírito Santo state, Brazil, fragments of restinga, which form a natural ecosystem, share their space with an increasing number of iron ore industries. The iron ore dust and SO2 originating from the industry processing activities can interfere with the vegetation of the adjacent ecosystems at various levels. This study was undertaken in order to evaluate the effects of industry emissions on representative members of the restinga flora, by measuring physiological and phenological parameters. Foliar samples of Ipomoea pes caprae, Canavalia rosea, Sophora tomentosa, and Schinus terebinthifolius were collected at three increasing distances from an ore industry (1.0, 5.0, and 15.0 km), and were assessed for their dust deposition, chlorophyll, and Fe content. Phenological monitoring was focused on the formation of shoots, flowers, and fruits and was also performed throughout the course of a year. The results showed that the edaphic characteristics and the mineral constitutions of the plants were affected by industry emissions. In addition, the chlorophyll content of the four species increased with proximity to the industry. Phenological data revealed that the reproductive effort, as measured by fruit production, was affected by emissions and S. tomentosa was the most affected species. The use of an integrative approach that combines biochemical and ecological data indicates that the restinga flora is under stress due to industry emissions, which on a long-term basis may put the ecosystem at risk.

  14. Understanding Cu release into environment from Kure massive sulfide ore deposits, Kastamonu, NW Turkey

    Science.gov (United States)

    Demirel, Cansu; Sonmez, Seref; Balci, Nurgul

    2014-05-01

    Covering a wide range on the earth's crust, oxidation of metal sulfide minerals have vital environmental impacts on the aquatic environment, causing one of the major environmental problems known as acid mine drainage (AMD). Located in the Kastamonu province of the Western Black Sea region, Kure district is one of the major copper mining sites in Turkey. Mining activities in the area heads back to ancient times, such that operation is thought to be started with the Roman Empire. Currently, only the underground mining tunnels of Bakibaba and Asikoy are being operated. Thus, mining heaps and ores of those pyritic deposits have been exposed to the oxidative conditions for so long. As a result of weathering processes of past and recent heaps of the Kure volcanic massive sulfide deposits in addition to the main ore mineral (chalcopyrite), significant amount of metals, especially Cu, are being released into the environment creating undesirable environmental conditions. In order to elucidate Cu release mechanisms from Kure pyritic ore deposits and mining wastes, field and laboratory approaches were used. Surface water and sediment samples from the streams around the mining and waste sites were collected. Groundwater samples from the active underground mining site were also collected. Physical parameters (pH, Eh, T°C, and EC) of water samples were determined in situ and in the laboratory using probes (WTW pH 3110, WTW Multi 9310 and CRISON CM 35). Metal and ion concentrations of the water samples were analysed using ICP-MS and DR 2800 spectrophotometer, respectively. High Cu, Co, Zn and Fe concentrations were determined in the water samples with pH values ranging from 2.9- 4. Cu concentrions ranges from 345 ppm to 36 ppm in the water samples. Consistent with the water samples, high Cu, Fe, Zn and Co were also determined in the sediment samples. Laboratory chalcopyrite oxidation experiments under the conditions representing the field site were set up as biological and

  15. Analysis of Ore-controlling Structure in the Qifengcha-Detiangou Gold Deposit, Huairou County, Beijing

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Qifengcha-Detiangou gold deposit is a medium-sized deposit recently found in Huairou County, Beijing. It belongs to the altered mylonite type with superimposed quartz vein type and is related to the early Yanshanian magmatic activity. Characterized by multiperiodic activity, the NE-trending Qifengcha fault is a regional ore-controlling structure in the area, and gold mineralization develops only in its southeastern part. Meanwhile, gold mineralization is controlled by the Yunmengshan metamorphic core complex. The nearly N-S- and E-W-trending low-angle detachment faults, reformed by the Qifengcha fault in the northwestern part of the core complex, are the main ore-bearing faults. All discovered gold deposits are located within an area 1.5(4.0 km away from the boundary of the upwelling centre. The N-S- (NNE-) and E-W-trending ore-bearing faults are ductile-brittle structural zones developing in shallow positions and subjected mainly to compressive deformation. The structural ore-controlling effects are as follows. (1) The attitude, shape, and distribution of gold orebodies are controlled by faults. (2) There is a negative correlation between the gold abundance and the magnetic anisotropy (P) of the altered mylonite samples from the deposit, which shows that the gold mineralization is later than the structural deformation. (3) Quartz vein type mineralization is superimposed on altered mylonite type mineralization. (4) In mineralized mylonite, the stronger the ductile shear deformation, the easier the late-stage gold mineralization to occur and the higher the gold abundance. The richest gold mineralization occurs only around the centre of the fault subjected to the strongest deformation.

  16. Application of Odor Sensors to Ore Sorting and Mill Feed Control

    Energy Technology Data Exchange (ETDEWEB)

    Michael G. Nelson

    2005-08-01

    Control of the feed provided to mineral processing facilities is a continuing challenge. Much effort is currently being devoted to overcoming these problems. These projects are usually described under the general headings of Mine-to-Mill Integration or Mine-Mill Optimization. It should be possible to combine the knowledge of ore type, mineralogy, and other characteristics (located in the mine modeling system), with the advanced capabilities of state-of-the-art mill control systems, to achieve an improved level of control in mineral processing that will allow optimization of the mill processes on an almost real-time basis. This is not happening because mill feed it is often treated as a uniform material, when in reality it varies in composition and characteristics. An investigation was conducted to assess the suitability of odor sensors for maintaining traceability in ore production and processing. Commercially available sensors are now used in food processing, environmental monitoring, and other applications and can detect the presence of very small amounts (0.1-500 ppm) of some molecules. An assortment of such molecules could be used to ''tag'' blocks of ore as they are mined, according to their respective characteristics. Then, as the ore came into the mill, an array of ''electronic noses'' could be used to assess its characteristics in real time. It was found that the Cyranose 320{trademark}, a commercially available odor sensor, can easily distinguish among samples of rock marked with almond, cinnamon, citronella, lemon, and orange oils. Further, the sensor could detect mixtures of rocks marked with various combinations of these oils. Treatment of mixtures of galena and silica with odorant compounds showed no detrimental effects on flotation response in laboratory tests. Additional work is recommended to determine how this concept can be extended to the marking of large volumes of materials.

  17. Direct reduction of low grade nickel laterite ore to produce ferronickel using isothermal - temperature gradient

    Science.gov (United States)

    Zulhan, Zulfiadi; Gibranata, Ian

    2017-01-01

    In this study, low grade nickel laterite ore was processed by means of isothermal-temperature gradient method to produce ferronickel nugget. The ore and coal as reductant were ground to obtain the grain size of less than 0.25 mm and 0.425 mm, respectively. Both ground laterite ore and coal were mixed, agglomerated in the form of cylindrical pellet by using press machine and then reduced at temperature of 1000°C to 1400°C in a muffle furnace. The experiments were conducted at three stages each at different temperature profile: the first stage was isothermal at 1000°C; the second stage was temperature gradient at certain heating rate from 1000 to 1400°C; and the third stage was isothermal at 1400°C. The heating rate during temperature gradient stage was varied: 6.67, 8.33 and 10°C/minute. No fluxes were added in these experiments. By addition of 10 wt% of coal into the laterite nikel ore, product of ferronickel nugget was formed with the size varies from 1-2 mm. However, by increasing the coal content, the size of ferronickel nugget was decreased to less than 0.2 mm. The observation of the samples during the heating stage showed that ferronickel nugget grew and separated from the gangue during temperature gradient stage as it achieved the temperature of 1380°C. Furthermore, the experiment results indicated that the recovery of ferronickel can be increased at lower heating rate during temperature gradient stage and longer holding time for final isothermal stage. The highest nickel recovery was obtained at a heating rate of 6.67°C/minute.

  18. XPS and FTIR spectroscopic study on microwave treated high phosphorus iron ore

    Energy Technology Data Exchange (ETDEWEB)

    Omran, Mamdouh, E-mail: mamdouh.omran@oulu.fi [Process Metallurgy Research Group, Faculty of Technology, University of Oulu (Finland); Mineral Processing and Agglomeration Lab, Central Metallurgical Research and Development Institute, Cairo (Egypt); Fabritius, Timo [Process Metallurgy Research Group, Faculty of Technology, University of Oulu (Finland); Elmahdy, Ahmed M.; Abdel-Khalek, Nagui A. [Mineral Processing and Agglomeration Lab, Central Metallurgical Research and Development Institute, Cairo (Egypt); El-Aref, Mortada; Elmanawi, Abd El-Hamid [Geology Department, Faculty of Science, Cairo University, Giza 12613 (Egypt)

    2015-08-01

    Highlights: • The effect of microwave radiation on structure and chemical state of high phosphorus iron ore was studied. • FTIR analyses showed that after microwave radiation the functional chemical groups of phosphorus bearing minerals (fluorapatite) dissociated. • High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). • Microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases. - Abstract: A growing interest in microwave heating has emerged recently. Several potential microwave applications regarding minerals’ processing have been investigated. This paper investigates the effect of microwave radiation on Egyptian high phosphorus iron ore. Three different iron ore samples have varying Fe{sub 2}O{sub 3} and P{sub 2}O{sub 5} contents and mineralogical textures were studied. A comparative study has been carried out between untreated and microwave treated iron ore. XRD and FTIR analyses showed that after microwave radiation the crystallinity of iron bearing minerals (hematite) increased, while the functional chemical groups of phosphorus bearing minerals (fluorapatite) and other gangues dissociated. High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). This means that after microwave radiation iron oxide (hematite, Fe{sup 3+}) transformed into more magnetic phase. The results indicated that microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases.

  19. Uranium and thorium recovery in thorianite ore-preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Gaiotte, Joao V.M. [Universidade Federal de Alfenas, Pocos de Caldas, MG (Brazil); Villegas, Raul A.S.; Fukuma, Henrique T., E-mail: rvillegas@cnen.gov.br, E-mail: htfukuma@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Pocos de Caldas, MG (Brazil). Lab. de Pocos de Caldas

    2011-07-01

    This work presents the preliminary results of the studies aiming to develop a hydrometallurgical process to produce uranium and thorium concentrates from thorianite ore from Amapa State, Brazil. This process comprises two major parts: acid leaching and Th/U recovery using solvent extraction strategies. Thorianite ore has a typical composition of 60 - 70% of thorium, 8 - 10% lead and 7 - 10% uranium. Sulfuric acid leaching operational conditions were defined as follows: acid/ore ratio 7.5 t/t, ore size below 65 mesh (Tyler), 2 hours leaching time and temperature of 100 deg C. Leaching tests results showed that uranium and thorium recovery exceeded 95%, whereas 97% of lead ore content remained in the solid form. Uranium and thorium simultaneous solvent extraction is necessary due to high sulfate concentration in the liquor obtained from leaching, so the Primene JM-T primary anime was used for this extraction step. Aqueous raffinate from extraction containing sulfuric acid was recycled to the leaching step, reducing acid uptake around 60%, to achieve a net sulfuric acid consumption of 3 t/t of ore. Uranium and thorium simultaneous stripping was performed using sodium carbonate solution. In the aqueous stripped it was added sulfuric acid at pH 1.5, followed by a second solvent extraction step using the tertiary amine Alamine 336. The following stripping step was done with a solution of sodium chloride, resulting in a final solution of 23 g L-1 uranium. (author)

  20. Study on the multi-sources of ore-forming materials and ore-forming fluids in the Huize lead-zinc ore deposit

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhenliang; HUANG Zhilong; GUAN Tao; YAN Zaifei; GAO Derong

    2005-01-01

    The Huize large-sized Pb-Zn deposit in Yunnan Province, China, is characterized by favorable metallogenic background and particular geological settings. This suggested that the ore-forming mechanism is relatively unique. On the basis of geological features such as the contents of mineralization elements, the REE concentrations of gangue calcites, the REE concentrations of calcite veins in the NE-trending tectonic zone and the Pb, Sr, C, H and O isotopic compositions of different minerals, this paper presents that the ore-forming materials and ore-forming fluids of the deposit were derived from various types of strata or rocks. This is a very significant conclusion for us to further discuss the mineralization mechanism of the deposit at depth and establish an available genetic model.

  1. KEY ROLE OF METALLOGENIC THEORY OF POLYGENETIC COMPOUND ORE DEPOSITS IN LOCATION PREDICTION OF HIDDEN ORE DEPOSITS IN DIWA REGIONS

    Institute of Scientific and Technical Information of China (English)

    PENG; Sheng-lin; LIU; Liang-ming; LAI; Jian-qing

    2001-01-01

    The metallogenic theory of polygenetic compound ore deposit is the Important basis for location prediction of hidden ore deposits in diwa regions.It can play an important role in each step of prediction research,targeting procedure,acquiring information and integrating information.In this paper,the authors discusses how to construct geological concept by using of the metallogenic theory of polygenetic ore deposits for predicting targeting area,to arrange investigation and detection for getting enough useful information,and to analyze and integrate information for reaching a trustful prediction conclusion.According to these strategies,we conduct a successful prediction of location of hidden ore bodies in the outer of the Fenghuangshan copper mine,a principal producing mine in Tongling Cu-Au district.

  2. Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

    Institute of Scientific and Technical Information of China (English)

    DENG; Jun; WANG; Qingfei; HUANG; Dinghua

    2006-01-01

    Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at -10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma's transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma's emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid's transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly increased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pressure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially

  3. Ceramic colorant from untreated iron ore residue.

    Science.gov (United States)

    Pereira, Oscar Costa; Bernardin, Adriano Michael

    2012-09-30

    This work deals with the development of a ceramic colorant for glazes from an untreated iron ore residue. 6 mass% of the residue was added in suspensions (1.80 g/cm(3) density and 30s viscosity) of white, transparent and matte glazes, which were applied as thin layers (0.5mm) on engobeb and not fired ceramic tiles. The tiles were fired in laboratory roller kiln in a cycle of 35 min and maximum temperatures between 1050 and 1180°C. The residue and glazes were characterized by chemical (XRF) and thermal (DTA and optical dilatometry) analyses, and the glazed tiles by colorimetric and XRD analyses. The results showed that the colorant embedded in the transparent glaze results in a reddish glaze (like pine nut) suitable for the ceramic roof tile industry. For the matte and white glazes, the residue has changed the color of the tiles with temperature. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Ferrite grade iron oxides from ore rejects

    Indian Academy of Sciences (India)

    K S Rane; V M S Verenkar; P Y Sawant

    2001-06-01

    Iron oxyhydroxides and hydroxides were synthesized from chemically beneficiated high SiO2/Al2O3 low-grade iron ore (57.49% Fe2O3) rejects and heated to get iron oxides of 96–99.73% purity. The infrared band positions, isothermal weight loss and thermogravimetric and chemical analysis established the chemical formulas of iron-oxyhydroxides as -FeOOH.0.3H2O; -FeOOH.0.2H2O and amorphous FeOOH. The thermal products of all these were -Fe2O3 excepting that of -FeOOH.0.3H2O which gave mainly -Fe2O3 and some admixture of -Fe2O3. The hydrazinated iron hydroxides and oxyhydroxides, on the other hand, decomposed autocatalytically to mainly -Fe2O3. Hydrazine method modifies the thermal decomposition path of the hydroxides. The saturation magnetization, s, values were found to be in the range 60–71 emu g–1 which are close to the reported values for -Fe2O3. Mechanism of the -Fe2O3 formation by hydrazine method is discussed.

  5. SIMS measurements of δ 34S in sulfide minerals from adjacent vein and stratabound ores

    Science.gov (United States)

    Macfarlane, Andrew W.; Shimizu, Nobumichi

    1991-02-01

    The effects of sample matrix and secondary ion energy on the instrumental fractionation of sulfur isotopes have been studied for troilite, pyrite, and galena using the Cameca IMS-3f ion microprobe. An analytical procedure is described for the measurement of δ 34S on negatively charged sulfur ions from pyrite and galena with a reproducibility better than ±1.5%. Sulfur isotope ratios were measured in pyrite and galena from adjacent stratabound manto orebodies and crosscutting veins in the Hualgayoc district of northern Peru. Isotopic compositions (δ 34S CDT) of sulfur in pyrite and galena from vein and manto deposits have a total range from -20 to 10%.. Sulfur in manto galenas has a wide range of isotopic compositions and is usually isotopically heavier than pyrite when both minerals have been analyzed in the same sample. Isotopic disequilibrium between pyrite and galena suggests precipitation from separate fluids, consistent with textural evidence that galena is paragenetically later than pyrite and often replaces it. Formation of ore minerals in the veins appears to have overlapped temporally with the later stages of manto mineralization and continued after manto formation ceased. Sulfur isotope values in pyrite and galena from veins are lower by about 5%. on average than the same sulfides in the mantos, and δ 34S values of vein galenas decrease over the course of vein formation. This shift of δ 34S toward lower values with time may be the result of increased mixing with sulfur from diagenetic sulfides or a decrease in the δ 34S value of aqueous sulfide due to oxidation of the ore fluid in the later stages of deposition. The latter hypothesis is favored because the lead isotopic compositions of the same vein minerals do not indicate an influx of sediment-derived lead and because of the appearance of barite in the final stages of several vein deposits. The majority of pyrite and galena analyses from vein and manto ores are compatible with precipitation from

  6. Characteristics and origin of ore-forming fluids of Jinchangqing gold (copper) ore deposit (s) in Xiangyun, Yunnan Province

    Institute of Scientific and Technical Information of China (English)

    HE Mingqin; SONG Huanbin; LIU Jiajun; LI Chaoyang

    2005-01-01

    On the basis of results of the studies of primary fluid inclusions, and the hydrogen and oxygen isotope data, the authors concluded that the early-stage ore-forming fluid from the Jinchangqing gold (copper) ore deposit is a kind of sulfate type hot brine characterized by medium temperature and salinity, genetically related to the late-stage ore-forming fluid derived from an acidic and more reductive environment. However, the late-stage ore-forming fluid is a sort of low temperature and low salinity chloride-type hot brine which originated from a lower pressure, acidic and more oxidative environment. In general, the ore fluids were derived from the late-stage, or largely from the early-stage groundwater-derived meteoric water, which has a 12‰-17‰ heavier oxygen isotopic composition than the original rain water (δ 18 O= -15.3‰ ), and were formed during gold mineralization as a product of oxygen isotope exchange during the reaction between ore-forming fluid and wall rocks under a lower water/rock ratio condition.

  7. Applicability of near-infrared hyperspectral imagery (NIR-HI) for sensor based sorting of an epithermal Au-Ag ore

    NARCIS (Netherlands)

    Dalm, M.; Buxton, M.W.N.; Van Ruitenbeek, F.J.A.

    2015-01-01

    In the presented study test work was performed with near-infrared hyperspectral imagery (NIR-HI) on 36 ore samples from a South-American epithermal Au-Ag mine. The aim of the test work was to investigate if NIR-HI provides information about the alteration mineralogy of samples that can be used to pr

  8. Childhood Lead Poisoning Associated with Gold Ore Processing: a Village-Level Investigation—Zamfara State, Nigeria, October–November 2010

    Science.gov (United States)

    Lo, Yi-Chun; Dooyema, Carrie A.; Neri, Antonio; Durant, James; Jefferies, Taran; Medina-Marino, Andrew; de Ravello, Lori; Thoroughman, Douglas; Davis, Lora; Dankoli, Raymond S.; Samson, Matthias Y.; Ibrahim, Luka M.; Okechukwu, Ossai; Umar-Tsafe, Nasir T.; Dama, Alhassan H.

    2012-01-01

    Background: During May–June 2010, a childhood lead poisoning outbreak related to gold ore processing was confirmed in two villages in Zamfara State, Nigeria. During June–September of that year, villages with suspected or confirmed childhood lead poisoning continued to be identified in Zamfara State. Objectives: We investigated the extent of childhood lead poisoning [≥ 1 child with a blood lead level (BLL) ≥ 10 µg/dL] and lead contamination (≥ 1 soil/dust sample with a lead level > 400 parts per million) among villages in Zamfara State and identified villages that should be prioritized for urgent interventions. Methods: We used chain-referral sampling to identify villages of interest, defined as villages suspected of participation in gold ore processing during the previous 12 months. We interviewed villagers, determined BLLs among children lead. Results: We identified 131 villages of interest and visited 74 (56%) villages in three local government areas. Fifty-four (77%) of 70 villages that completed the survey reported gold ore processing. Ore-processing villages were more likely to have ≥ 1 child lead poisoning (68% vs. 50%, p = 0.17) or death following convulsions (74% vs. 44%, p = 0.02). Soil/dust contamination and BLL ≥ 45 µg/dL were identified in ore-processing villages only [50% (p lead poisoning or lead contamination was 3.5 times as high in ore-processing villages than the other villages (95% confidence interval: 1.1, 11.3). Conclusion: Childhood lead poisoning and lead contamination were widespread in surveyed areas, particularly among villages that had processed ore recently. Urgent interventions are required to reduce lead exposure, morbidity, and mortality in affected communities. PMID:22766030

  9. Fluorosilicone and silicone o-ring aging study.

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, Robert; Gillen, Kenneth T.

    2007-10-01

    Fluorosilicone o-ring aging studies were performed. These studies examined the compressive force loss of fluorosilicone o-rings at accelerated (elevated) temperatures and were then used to make predictions about force loss at room temperature. The results were non-Arrhenius with evidence for a lowering in Arrhenius activation energies as the aging temperature was reduced. The compression set of these fluorosilicone o-rings was found to have a reasonably linear correlation with the force loss. The aging predictions based on using the observed curvature of the Arrhenius aging plots were validated by field aged o-rings that yielded degradation values reasonably close to the predictions. Compression set studies of silicone o-rings from a previous study resulted in good correlation to the force loss predictions for the fluorosilicone o-rings from this study. This resulted in a preliminary conclusion that an approximately linear correlation exists between compression set and force decay values for typical fluorosilicone and silicone materials, and that the two materials age at similar rates at low temperatures. Interestingly, because of the observed curvature of the Arrhenius plots available from longer-term, lower temperature accelerated exposures, both materials had faster force decay curves (and correspondingly faster buildup of compression set) at room temperature than anticipated from typical high-temperature exposures. A brief study on heavily filled conducting silicone o-rings resulted in data that deviated from the linear relationship, implying that a degree of caution must be exercised about any general statement relating force decay and compression set.

  10. 微波消解-耐氢氟酸系统进样电感耦合等离子体发射光谱法测定锰矿中铝磷镁铁锌镍%Determination of aluminum, phosphorus, magnesium, iron, zinc and nickel in manganese ore by inductively coupled plasma atomic emission spectrometry with hydrofluoric add resistant sampling system after microwave digestion

    Institute of Scientific and Technical Information of China (English)

    邓全道; 许光; 林冠春; 刘建发; 刘灵芝

    2011-01-01

    采用混合酸作溶剂微波消解试样,样液定客后,直接用耐氢氟酸进样系统(Duo HF KIT)进样,电感耦合等离子体发射光谱法(ICP-AES)测定锰矿石试液中的铝、磷、镁、铁、锌、镍,避免因为引入硼酸掩蔽氟离子而带来的基体干扰,缩短了检测时间.测定时选择波长为369.152 nm{85}、186.942 nm{481}、280.270 nm{120}、240.488 nm{140}、213.856 nm{457}和341.476 nm{99}光谱线分别作为Al、P、Mg、Fe、Zn、Ni分析线,采用基体匹配方法来消除锰的基体效应.本法已测定国家锰矿标准物质中铝、磷、镁、铁、锌、镍,并与国标方法测定结果相比对,分析结果与认定值及国标方法的测定值相符,且重复性好.各元素的加标回收率为94%~107%,测定结果的相对标准偏差(RSD,n=12)小于1.1%.%The samples were dissolved by microwave digestion using mixed acid as solvent. After dilution, the aluminum, phosphorus, magnesium, iron, zinc and nickel in manganese ore were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) using hydrofluoric acid resistant sampling system (Duo HF KIT). The matrix effect of boric acid introduced for masking fluorine ion was prevented , and the detection time was shortened. The spectral lines for Al, P, Mg, Fe, Zn and Ni were 369. 152 nm{ 85 } , 186. 942 nm{ 481 } , 280. 270 nm{120} , 240. 488 nm {140} , 213. 856 nm {457} and 341. 476 nm {99}, respectively. The matrix effect of manganese was eliminated by matrix matching method. The proposed method had been applied to the determination of aluminum, phosphorus, magnesium, iron, zinc and nickel in certified reference materials of manganese ore. The determination results were compared with those obtained by national standard method. It was found that the analytical results were consistent with the certified values and those obtained by national standard method. Moreover, the repeatability was good. The recoveries of elements were 94%-107

  11. The potential for ore, industrial minerals and commercial stones in the Simpevarp area

    Energy Technology Data Exchange (ETDEWEB)

    Lindroos, Hardy [MIRAB Mineral Resurser AB, Uppsla (Sweden)

    2004-10-01

    On behalf of SKB (the Swedish Nuclear Fuel and Waste Management Company), a survey has been made of existing information concerning the potential for ore, industrial minerals and commercial stones in and around the two candidate areas for a deep repository in Oskarshamn. A deep repository for spent nuclear fuel should not be located in a rock type or in an area where mineral extraction might be considered in the future, since this would make it difficult or impossible to exploit this natural resource. Avoiding such areas reduces the risk that people in the future will come into contact with the deep repository through mineral prospecting or mining activities.The survey has made use of the geoscientific information compiled in the more regional investigations in Oskarshamn Municipality in 1998-99. The new information after the municipal study includes extensive geophysical measurements from both the air and the ground. The results of the recently completed geophysical helicopter survey of the Simpevarp area are presented in a special chapter. The judgement of an area's ore potential is in part based on the evaluation of these geophysical measurements. In order to be better able to judge the ore potential, a geochemical investigation of soil samples, including reanalysing of older samples collected by the Geological Survey of Sweden (SGU), has been carried out. The report also discusses prospecting efforts in the area as well as relevant Swedish mining legislation. In cooperation with SGU a mineral resource map of the Simpevarp area has been prepared. The map shows two areas with a potential for commercial stones, namely the granites at Goetemar and Uthammar, situated in the northernmost respectively the southernmost part of the study area. Furthermore, the Goetemar granite has probably a small potential for ores containing tin (Sn) and/or wolfram (W). Although no mineralizations of this type have so far been found, the Goetemar granite area may be unsuitable or

  12. BOD determination parameters; BOD. Da cinque giorni a cinque ore

    Energy Technology Data Exchange (ETDEWEB)

    Scarano, E.; Bottari, E.; Mantarro, M. [Rome Univ. La Sapienza, Rome (Italy). Dipt. di Chimica; Pellegrini, G. E. [Istituto Superiore di Sanita' , Lab. di Micologia, Rome (Italy)

    2001-06-01

    An important parameter of those according the law, with regards waste waters and representing a required analytical determination according the national rules on the check of the good working of a depurator is the biological oxygen demand (BOD). The currently applied method is affected by several limitations. It has low accuracy and precision, is strongly depending on the sampling, is time wasting and its application and performance can present different and hard difficulties of execution. However, the result of the analysis cannot be obtained before of five days. By taking into account all these complications, an alternative method is here proposed. The proposed procedure is less manipulative, is more precise and is able to furnish the result within about 5 hours from the start of the chemical analysis. The proposed method was applied successful to sample of a cesspool water depurator and the good results will be shown in the text. [Italian] Uno dei parametri che deve essere valutato per legge nelle acque di scarico e che costituisce una irrinunciabile determinazione analitica per il controllo del buon funzionamento di un depuratore e' la richiesta biologica di ossigeno (BOD, biological oxygen demand). Il metodo generalmente adoperato risulta limitato da una scarsa accuratezza e precisione, e' fortemente dipendente dalle modalita' di prelievo dei campioni, e' laborioso e certamente e' estremamente lungo. Il risultato si puo' conoscere non prima di cinque giorni. Tenendo presente tutte queste limitazioni, viene proposto un metodo alternativo che, essendo meno manipolativo, con una precisione migliore riesce a dare una risposta nel giro di circa 5 ore dall'inizio dell'analisi. Il metodo e' stato applicato con successo alle acque di un depuratore di acque cloacali e se ne riportano i risultati.

  13. Dolomite flotation of high magnesium phosphate ores using fatty acid soap collectors

    Science.gov (United States)

    Gu, Zhengxing

    The separation of dolomite from apatite has been recognized as one of the most difficult subjects in mineral processing due to the similarities in their physiochemical properties. In this study, selective surfactants were used with a fatty acid soap collector to improve the flotation performance of separating dolomite from high magnesium phosphate ores. Three surfactants, diethyl phthalate (DP), Tween-80 (TW) and derivative of sulfonate salt (DSS1) were used. Hallimond cell flotation was conducted using pure dolomite sample to determine the effects of various factors including dosages, particle size, Ca2+ ions and slimes on the dolomite flotation recovery. The results showed that the surfactants can significantly improve dolomite flotation performance by increasing collecting ability and tolerating the effect of calcium ions and slime contents. The stirrer-tank cell batch flotation tests were carried out using two natural high magnesium phosphate ore samples containing 3.3% and 1.5% MgO. The test results showed that the surfactant DP could improve dolomite flotation at low dosages, and DSS1 could enhance the separation of dolomite from phosphate by improving both collecting ability and flotation selectivity. When 10% of DSS1 was used with the fatty acid soap as collector, at least 10% more dolomite can be removed with less P2O5 loss. The effectiveness of the surfactant DSS1 in enhancing dolomite flotation was further demonstrated in modified packed column flotation with natural dolomitic phosphate ore sample. The addition of the surfactant DSS1 into fatty acid soap collector could improve its frothability and froth stability, and reduce the bubble size. It has been found that the dolomite flotation performance has a close relationship with the frothability and froth stability of the collector.

  14. Existing State and Partitioning of Rare Earth on Weathered Ores

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The existing state and partitioning of rare earth (RE) on weathered ores in Longnan County (LN), Xingfeng County(XF) and Ninghua County(NH) were characterized systematically by standard geological analytical methods. It is found that RE in the weathered rare earth ores exist as four phases: (a) water soluble, (b) ion-exchangeable, (c) colloidal sediment (oxides), (d) minerals, in which mainly as ion exchangeable phase, accounting for nearly 80% of total RE,with about 20% in the form of colloid sediment phase and mineral phase, but very little as aqueous soluble phase. These rare earth partitioning were mainly chosen mid-heavy RE elements, occupying above 60%, but not equal in the four phases. The mid-heavy RE elements were primarily enriched in the ion exchangeable phase up to 40%, while the containment of cerium dioxide is below 2%. The cerium deficiency occurs in the ion exchangeable phase in weathered ore. It results from that the Ce3+ is oxidized into Ce4+ and changes into CeO2. For LN ore, the containment of Y is high in weathered ore because Y-minerals are abundant in original rock.

  15. Flotation technology of refractory low-grade molybdenum ore

    Institute of Scientific and Technical Information of China (English)

    Du Shuhua; Luo Zhenfu

    2013-01-01

    Because of the low grade,high oxidation rate and the accumulation of little associated metal sulfide ore in the molybdenum concentrate during flotation,the Qingyang molybdenum ore is difficult to beneflciate.The experimental studies of grinding fineness,the amount of roughing modifier,depressant and collector were completed.In the cleaning process,the contrast experiments of one regrinding.the regrinding and scrubbing,two-stage regrinding was carried.The result shows that the grade of molybdenum ore concentrate is 45.31%,the recovery is 65.98% and the rich ore ratio reaches 20.59% by the regrinding and scrubbing seven cleaning,the regrinding of concentrations from middling of molybdenum-sulfur separation.The regularly-concentrated material from the apparatus was as the middling products.Hence,ideal beneficiation index can be obtained with a rational mineral processing,which offers new beneficiating technology for the refractory low-grade molybdenum ore in China.

  16. NOVEL BINDERS AND METHODS FOR AGGLOMERATION OF ORE

    Energy Technology Data Exchange (ETDEWEB)

    S.K. Kawatra; T.C. Eisele; J.A. Gurtler; C.A. Hardison; K. Lewandowski

    2004-04-01

    Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily. Primary examples of this are copper heap leaching, where there are no binders that will work in the acidic environment encountered in this process, and advanced ironmaking processes, where binders must function satisfactorily over an extraordinarily large range of temperatures (from room temperature up to over 1200 C). As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching and advanced primary ironmaking.

  17. Geochemical and stable isotopic data on barren and mineralized drill core in the Devonian Popovich Formation, Screamer sector of the Betze-Post gold deposit, northern Carlin trend, Nevada

    Science.gov (United States)

    Christiansen, William D.; Hofstra, Albert H.; Zohar, Pamela B.; Tousignant, Gilles

    2011-01-01

    The Devonian Popovich Formation is the major host for Carlin-type gold deposits in the northern Carlin trend of Nevada. The Popovich is composed of gray to black, thin-bedded, calcareous to dolomitic mudstone and limestone deposited near the carbonate platform margin. Carlin-type gold deposits are Eocene, disseminated, auriferous pyrite deposits characterized by acid leaching, sulfidation, and silicification that are typically hosted in Paleozoic calcareous sedimentary rocks exposed in windows through siliceous sedimentary rocks of the Roberts Mountains allochthon. The Carlin trend currently is the largest gold producer in the United States. The Screamer ore zone is a tabular body on the periphery of the huge Betze-Post gold deposit. Screamer is a good place to study both the original lithogeochemistry of the Popovich Formation and the effects of subsequent alteration and mineralization because it is below the level of supergene oxidation, mostly outside the contact metamorphic aureole of the Jurassic Goldstrike stock, has small, high-grade ore zones along fractures and Jurassic dikes, and has intervening areas with lower grade mineralization and barren rock. In 1997, prior to mining at Screamer, drill core intervals from barren and mineralized Popovich Formation were selected for geochemical and stable isotope analysis. The 332, five-foot core samples analyzed are from five holes separated by as much as 2000 feet (600 meters). The samples extend from the base of the Wispy unit up through the Planar and Soft sediment deformation units into the lower part of the upper Mud unit of the Popovich Formation.

  18. The production and use of citric acid for the removal of potassium from the iron ore concentrate of the Sishen Iron Ore Mine, South Africa

    Directory of Open Access Journals (Sweden)

    Peter J. Williams

    2010-04-01

    Full Text Available The depletion of the richer iron ore worldwide has made it necessary to process lower quality iron ore. Certain substances, such as potassium, contained within the lower quality iron ore, have a detrimental effect on the smelting process during steel manufacturing. Therefore, international steel-making companies charge penalties when purchasing iron ore concentrates containing high concentrations of potassium. To date, lower quality iron ore has been blended with high quality iron ore in an attempt to alleviate the potassium concentrations in the export iron ore; however, the ratio of low quality iron ore to high quality iron ore is increasing, thereby becoming an escalating problem within the economic functioning of the Sishen Iron Ore Mine. It has, therefore, become necessary to develop an economically viable and environmentally friendly process to reduce the high potassium concentrations contained in the iron ore concentrate of the Sishen Iron Ore Mine. In this study, we compared solid substrate and submerged fermentation using Aspergillus niger for the production of citric acid, which is used for the chemical leaching of potassium from the iron ore concentrate. It was found that submerged fermentation proved to be more economical and efficient, producing a maximum citric acid concentration of 102.3 g/L in 96 h of fermentation. ‘Heap leaching’ simulation experiments were found to be uneconomical, due to the required addition of fungal growth medium every 5 days as a result of growth factor depletion within this time; however, this process removed 17.65% of the potassium from the iron ore concentrate. By contrast, chemical leaching of potassium from the iron ore concentrate proved to be most efficient when using a 1 mol citric acid leaching solution at 60 ºC, removing 23.53% of the potassium contained within the iron ore concentrate. Therefore, the most economical and efficient process for the removal of potassium from the iron

  19. STATUS REPORT FOR AGING STUDIES OF EPDM O-RING MATERIAL FOR THE H1616 SHIPPING PACKAGE

    Energy Technology Data Exchange (ETDEWEB)

    Stefek, T.; Daugherty, W.; Skidmore, E.

    2012-08-31

    temperature ranges from 174 days for the 300 F vessel to 189 days for the 160 F vessel as of 8/1/2012. The compression stress-relaxation (CSR) behavior of H1616 shipping package O-rings is being evaluated to develop an aging model based on material properties. O-ring segments were initially aged at four temperatures (175 F, 235 F, 300 F and 350 F). These temperatures were selected to bound normal service temperatures and to challenge the seals within a reasonable aging period. Currently, samples aging at 300 F and 350 F have reached the mechanical failure point (end of life) which is defined in this study as 90% loss of initial sealing force. As a result, additional samples more recently began aging at {approx}270 F to provide additional data for the aging model. Aging and periodic leak testing of the full containment vessels, as well as CSR testing of O-ring segments is ongoing. Continued testing per the Task Technical Plan is recommended in order to validate the assumptions outlined in this status report and to quantify and validate the long-term performance of O-ring seals under actual service conditions.

  20. Chemical state mapping of heterogeneous reduction of iron ore sinter

    Science.gov (United States)

    Kimura, M.; Takeichi, Y.; Murao, R.; Obayashi, I.; Hiraoka, Y.; Liu, Y.

    2017-06-01

    Iron ore sinter constitutes the major component of the iron-bearing burden in blast furnaces, and its reduction mechanism is one of the keys to improving the productivity of ironmaking. Iron ore sinter is composed of multiple iron oxide phases and calcium ferrites (CFs), and their heterogeneous reduction was investigated in terms of changes in iron chemical state: FeIII, FeII, and Fe0 were examined macroscopically by 2D X-ray absorption and microscopically by 3D transmission X-ray microscopy (TXM). It was shown that the reduction starts at iron oxide grains rather than at calcium ferrite (CF) grains, especially those located near micropores. The heterogeneous reduction causes crack formation and deteriorates the mechanical strength of the sinter. These results help us to understand the fundamental aspects of heterogeneous reduction schemes in iron ore sinter.

  1. Complex sulphide-barite ore leaching in ferric chloride solution

    Directory of Open Access Journals (Sweden)

    Miroslav Sokić

    2016-06-01

    Full Text Available The results of research on the leaching process of complex sulphide-barite ore were presented in this paper. The leaching process was carried out in a laboratory autoclave by ferric chloride solution. Considering that those minerals are represented in complex structural-textural relationships, it is not possible to extract lead, zinc and copper minerals from ore by flotation methods. The obtained results confirmed possibility of the ore processing directly, by chemical methods. The effect of temperature, time and oxygen partial pressure on the lead, zinc and copper dissolution was studied. The maximal leaching degree was achieved at 100 °C and amount of 91.5 % for Pb, 96.1 % for Zn and 60.7 % for Cu. Leaching at temperatures above 100 °C is impractical.

  2. A hybrid decision support system for iron ore supply

    Directory of Open Access Journals (Sweden)

    A. Samolejová

    2012-01-01

    Full Text Available Many European metallurgical companies are forced to import iron ore from remote destinations. For these companies it is necessary to determine the amount of iron ore that will have to be ordered and to create such a delivery schedule so that the continuous operation of blast-furnace plant is not disrupted and there is no exceedingly large stock of this raw material. The objective of this article is to design the decision support system for iron ore supply which would effi ciently reduce uncertainty and risk of that decision-making. The article proposes a hybrid intelligent system which represents a combination of diff erent artifi cial intelligence methods with dynamic simulation technique for that purpose.

  3. Treatment of coking wastewater by using manganese and magnesium ores.

    Science.gov (United States)

    Chen, Tianhu; Huang, Xiaoming; Pan, Min; Jin, Song; Peng, Suchuan; Fallgren, Paul H

    2009-09-15

    This study investigated a wastewater treatment technique based on natural minerals. A two-step process using manganese (Mn) and magnesium (Mg) containing ores were tested to remove typical contaminants from coking wastewater. Under acidic conditions, a reactor packed with Mn ore demonstrated strong oxidizing capability and destroyed volatile phenols, chemical oxygen demand (COD)(,) and sulfide from the coking wastewater. The effluent was further treated by using Mg ore to remove ammonium-nitrogen and phosphate in the form of magnesium ammonium phosphate (struvite) precipitates. When pH of the wastewater was adjusted to 1.2, the removal efficiencies for COD, volatile phenol and sulfide reached 70%, 99% and 100%, respectively. During the second step of precipitation, up to 94% of ammonium was removed from the aqueous phase, and precipitated in the form of struvite with phosphorus. The struvite crystals showed a needle-like structure. X-ray diffraction and transmission electron microscopy were used to characterize the crystallized products.

  4. Calcination-Digestion-Desliming of Phosphorus Ore Bearing Rare Earth

    Institute of Scientific and Technical Information of China (English)

    Zhang Qin; Zhang Jie; Wang Jing; Qiu Yue qin

    2004-01-01

    The recoveries of phosphorus and RE of ore from Zhijin in Guizhou were studied.The influences of the calcination temperature, resident time, the digested time and water volume of the calcinating on concentrate yield by desliming were also investigated by orthogonal design.Appropriate calcination temperature is initial condition that makes carbonate mineral decomposition.The recovery of phosphorus is 83.02% and rare earth is 90.56% in phosphorus concentrate when calcined temperature is 900 ℃, other conditions include: calcined time is 30 min, digestion water volume is 300 ml, digestion time is 20 min.The results show that the pre-treatment of the ore is favorable for the separation and enrichment of rare earth from phosphorus ore, and a process of calcination-digestion-desliming was promised.

  5. Fossil bacteria in Xuanlong iron ore deposits of Hebei Province

    Institute of Scientific and Technical Information of China (English)

    DAI Yongding; SONG Haiming; SHEN Jiying

    2004-01-01

    Discovered in Early Proterozoic Xuanlong iron ore deposits are six genera of fossil iron bacteria, i. e. sphere (coenobium of) rod-shaped (monomer) Naumanniella, ellipsoid elliptical Ochrobium, sphere spherical Siderocapsa and chain spherical Siderococcus, chain rod-shaped Leptothrix and Lieskeella, and six genera of fossil blue bacteria, namely sphere spherical Gloeocapsa, Synechocystis and Globobacter, chain spherical Anabaena and Nostoc, and constrictive septate tubular Nodularia. The biomineralized monomers and coenobia of the two categories of bacteria, together with hematite plates made up the bacteria pelletal, bacteria silky,bacteria fibrous and clasty bacteria pelletal textural lamina. The bacteria pelletal laminae combined with other bacteria laminae to make up oncolite, stromatolite and laminate. The precipitation of iron oxide was accelerated due to iron and blue bacteria cohabiting on microbial film or mat. The Xuanlong iron ore deposits are microbial binding ore deposits of ocean source.

  6. Novel Binders and Methods for Agglomeration of Ore

    Energy Technology Data Exchange (ETDEWEB)

    S. K. Kawatra; T. C. Eisele; K. A. Lewandowski; J. A. Gurtler

    2006-12-31

    Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily. Primary examples of this are copper heap leaching, where there are no binders that will work in the acidic environment encountered in this process, and advanced ironmaking processes, where binders must function satisfactorily over an extraordinarily large range of temperatures (from room temperature up to over 1200 C). As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching and advanced primary ironmaking. This project has identified several acid-resistant binders and agglomeration procedures that can be used for improving the energy efficiency of heap leaching, by preventing the ''ponding'' and ''channeling'' effects that currently cause reduced recovery and extended leaching cycle times. Methods have also been developed for iron ore

  7. Control of Rock Mechanics in Underground Ore Mining

    Science.gov (United States)

    Golik, V. I.; Efremenkov, A. B.

    2017-07-01

    Performance indicators in underground mining of thick iron fields can be insufficient since geo-mechanic specifics of ore-hosting fields might be considered inadequately, as a consequence, critical deformations and even earth’s surface destruction are possible, lowering the indicators of full subsurface use, this way. The reason for it is the available approach to estimating the performance of mining according to ore excavation costs, without assessing losses of valuable components and damage to the environment. The experimental approach to the problem is based on a combination of methods to justify technical capability and performance of mining technology improvement with regard to geomechanical factors. The main idea of decisions to be taken is turning geo-materials into the condition of triaxial compression via developing the support constructions of blocked up structural rock block. The study was carried out according to an integrated approach based on the analysis of concepts, field observations, and simulation with the photo-elastic materials in conditions of North Caucasus deposits. A database containing information on the deposit can be developed with the help of industrial experiments and performance indicators of the field can be also improved using the ability of ore-hosting fields to develop support constructions, keeping the geo-mechanical stability of the system at lower cost, avoiding ore contamination at the processing stage. The proposed model is a specific one because an adjustment coefficient of natural and anthropogenic stresses is used and can be adopted for local conditions. The relation of natural to anthropogenic factors can make more precise the standards of developed, prepared and ready to excavation ore reserves relying on computational methods. It is possible to minimize critical stresses and corresponding deformations due to dividing the ore field into sectors safe from the standpoint of geo-mechanics, and using less cost

  8. Isolation and identification of iron ore-solubilising fungus

    Directory of Open Access Journals (Sweden)

    Damase Khasa

    2010-09-01

    Full Text Available Potential mineral-solubilising fungi were successfully isolated from the surfaces of iron ore minerals. Four isolates were obtained and identified by molecular and phylogenetic methods as close relatives of three different genera, namely Penicillium (for isolate FO, Alternaria (for isolates SFC2 and KFC1 and Epicoccum (for isolate SFC2B. The use of tricalcium phosphate (Ca3(PO42in phosphate-solubilising experiments confirmed isolate FO as the only phosphate solubiliser among the isolated fungi. The bioleaching capabilities of both the fungus and its spent liquid medium were tested and compared using two types of iron ore materials, conglomerate and shale, from the Sishen Iron Ore Mine as sources of potassium (K and phosphorus (P. The spent liquid medium removed more K (a maximum of 32.94% removal, from conglomerate, than the fungus (a maximum of 21.36% removal, from shale. However, the fungus removed more P (a maximum of 58.33% removal, from conglomerate than the spent liquid medium (a maximum of 29.25% removal, from conglomerate. The results also indicated a potential relationship between the removal of K or P and the production of organic acids by the fungus. A high production of gluconic acid could be related to the ability of the fungus to reduce K and P. Acetic, citric and maleic acids were also produced by the fungus, but in lower quantities. In addition, particle size and iron ore type were also shown to have significant effects on the removal of potassium and phosphorus from the iron ore minerals. We therefore conclude that the spent liquid medium from the fungal isolate FO can potentially be used for biobeneficiation of iron ore minerals.

  9. Novel Binders and Methods for Agglomeration of Ore

    Energy Technology Data Exchange (ETDEWEB)

    S. K. Kawatra; T. C. Eisele; K. A. Lewandowski; J. A. Gurtler

    2006-12-31

    Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily. Primary examples of this are copper heap leaching, where there are no binders that will work in the acidic environment encountered in this process, and advanced ironmaking processes, where binders must function satisfactorily over an extraordinarily large range of temperatures (from room temperature up to over 1200 C). As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching and advanced primary ironmaking. This project has identified several acid-resistant binders and agglomeration procedures that can be used for improving the energy efficiency of heap leaching, by preventing the ''ponding'' and ''channeling'' effects that currently cause reduced recovery and extended leaching cycle times. Methods have also been developed for iron ore

  10. [Assessment of Soil Fluorine Pollution in Jinhua Fluorite Ore Areas].

    Science.gov (United States)

    Ye, Qun-feng; Zhou, Xiao-ling

    2015-07-01

    The contents of. soil total fluorine (TF) and water-soluble fluorine (WF) were measured in fluorite ore areas located in Jinhua City. The single factor index, geoaccumulation index and health risk assessment were used to evaluate fluorine pollution in soil in four fluorite ore areas and one non-ore area, respectively. The results showed that the TF contents in soils were 28. 36-56 052. 39 mg.kg-1 with an arithmetic mean value of 8 325.90 mg.kg-1, a geometric mean of 1 555. 94 mg.kg-1, and a median of 812. 98 mg.kg-1. The variation coefficient of TF was 172. 07% . The soil WF contents ranged from 0. 83 to 74. 63 mg.kg-1 with an arithmetic mean value of 16. 94 mg.kg-1, a geometric mean of 10. 59 mg.kg-1, and a median of 10. 17 mg.kg-1. The variation coefficient of WF was 100. 10%. The soil TF and WF contents were far higher than the national average level of the local fluorine epidemic occurrence area. The fluoride pollution in soil was significantly affected by human factors. Soil fluorine pollution in Yangjia, Lengshuikeng and Huajie fluorite ore areas was the most serious, followed by Daren fluorite ore area, and in non-ore area there was almost no fluorine pollution. Oral ingestion of soils was the main exposure route. Sensitivity analysis of model parameters showed that children's weight exerted the largest influence over hazard quotient. Furthermore, a significant positive correlation was found among the three kinds of evaluation methods.

  11. Challenges facing the North American iron ore industry

    Science.gov (United States)

    Jorgenson, J.D.

    2005-01-01

    During the 20th century, the iron ore mining industries of Canada and the United States passed through several periods of transformation. The beginning of the 21st century has seen yet another period of transformation, with the economic failure of a number of steel companies, the acquisition of their facilities by more viable steelmakers, and the consolidation of control within the North American iron ore industry. Changes in Canadian and United States iron ore production and the market control structure involved are analysed. The consolidation of ownership, formation of foreign joint ventures within Nordi America, planned divestitures of upstream activities by steelmakers, and industry changes made to ensure availability of feedstocks will be reviewed. The ttaditional isolation of the Canadian and United States iron ore operations and their strong linkage to downstream steel production will be discussed in the context of a changing global economy. Management-labour conflicts that have taken place and agreements made during 2000 through 2004 will be discussed in the context of the economic environment leading up to these agreements. Cooperative agreements between competing Canadian and United States companies to resolve client needs in processing and blending will be examined. A joint industry-government project designed to use new technology to produce direct reduced iron nuggets of 96 - 98 per cent iron content using non-coking coals will also be assessed. Changes in iron ore transportation methods, ownership and infrastructure will be reviewed for both rail and inland waterway transport between Canadian and United States companies. A brief analysis of social and environmental issues relating to sustainable development of the Canadian-United States iron ore industry will be included.

  12. Sulfate Saturated Hydrous Magmas Associated with Hydrothermal Gold Ores

    Science.gov (United States)

    Chambefort, I.; Dilles, J. H.; Kent, A. J.

    2007-12-01

    Hydrothermal ore deposits associated with arc magmatism represent important sulfur anomalies. During degassing of magmatic systems the volatile may transport metals and sulfur and produce deposits. The ultimate origin of the magma-derived sulfur is still uncertain. The Yanacocha high-sulfidation epithermal Au deposit, Peru, is hosted by a Miocene volcanic succession (ca. 16 to 8 Ma). Magmatic rocks are highly oxidized >NNO+2 and show a range of composition from andesite to dacite. Two populations of amphibole occur in the Yanacocha dacitic ignimbrite deposits (~7 and 12 wt% Al2O3). Low Al amphiboles crystallized at ~ 1.5-2 kbar and 800°C (Plag-Hb thermobarometry) in equilibrium with plagioclase and pyroxene. High Al amphiboles only contain inclusions of anhydrite associated with apatite (up to 1.2 wt% SO3), and have a higher Cr2O3 content (up to 1000 ppm). We estimate these amphiboles form near the magma's liquidus at P(H2O)> 3kbar and 950 to 1000°C of a basaltic, basaltic andesite ascending magma. Low Al amphibole presents an REE pattern with negative anomalies in Sr, Ti and Eu, characteristic of plagioclase and titanite fractionation in the magma. High Al amphiboles are less enriched in REE and have no Sr, Ti, or Eu anomaly. Rare crystals of high Al amphibole display a low Al rim marked by higher REE contents compared to the core and a negative Eu anomaly. Magmatic sulfate occurrences have been discovered through the 8 m.y. volcanic sequence. Rounded anhydrite crystals are found included within clinopyroxene and both high and low Al amphibole. The rare high Al amphiboles (from the sample RC6) contain up to ~10 vol.%, ~5-80 micrometer-long anhydrite as irregularly shaped (amoeboid) blebs that do not show crystallographic forms and do not follow host cleavages. Extremely rare sulfide inclusions are found in plagioclase (Brennecka, 2006). The major and trace element contents of Yanacocha magmatic anhydrite have been analyzed by electron microprobe and LA

  13. Enhanced Uranium Ore Concentrate Analysis by Handheld Raman Sensor: FY15 Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, Samuel A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Timothy J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Orton, Christopher R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-11-11

    High-purity uranium ore concentrates (UOC) represent a potential proliferation concern. A cost-effective, “point and shoot” in-field analysis capability to identify ore types, phases of materials present, and impurities, as well as estimate the overall purity would be prudent. Handheld, Raman-based sensor systems are capable of identifying chemical properties of liquid and solid materials. While handheld Raman systems have been extensively applied to many other applications, they have not been broadly studied for application to UOC, nor have they been optimized for this class of chemical compounds. PNNL was tasked in Fiscal Year 2015 by the Office of International Safeguards (NA-241) to explore the use of Raman for UOC analysis and characterization. This report summarizes the activities in FY15 related to this project. The following tasks were included: creation of an expanded library of Raman spectra of a UOC sample set, creation of optimal chemometric analysis methods to classify UOC samples by their type and level of impurities, and exploration of the various Raman wavelengths to identify the ideal instrument settings for UOC sample interrogation.

  14. Ore-forming Conditions and Prospecting in the West Kunlun Area, Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    DONG Yongguan; GUO Kunyi; XIAO Huiliang; ZHANG Chuanlin; ZHAO Yu

    2004-01-01

    The West Kunlun ore-forming belt is located between the northwestern Qinghai-Tibet Plateau and southwestern Tarim Basin. It situated between the Paleo-Asian Tectonic Domain and Tethyan Tectonic Domain. It is an important component of the giant tectonic belt in central China (the Kunlun-Qilian-Qinling Tectonic Belt or the Central Orogenic Belt). Many known ore-forming belts such as the Kunlun-Qilian Qinling ore-forming zone, Sanjiang (or Threeriver) ore-forming zone, Central Asian ore-forming zone, etc. pass through the West Kunlun area. Three ore-forming zones and seven ore-forming subzones were classified, and eighteen mineralization areas were marked. It is indicated that the West Kunlun area is one of the most favorable region for finding out large and superlarge ore deposits.

  15. A study of the distribution of rare-metals in kuroko-type ore

    Energy Technology Data Exchange (ETDEWEB)

    Murao, S. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW (Australia). Div. of Exploration Geoscience]|[Geological Survey of Japan, Tsukuba, Ibaraki (Japan); Sie, S.H.; Suter, G.F. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW (Australia). Div. of Exploration Geoscience

    1996-12-31

    We have performed PIXE analysis of kuroko-type ore from the JADE hydrothermal site of the Okinawa Trough, Japan using the proton microprobe (PIXEPROBE). We analysed five kinds of ores dredged from the sea floor: (I) barite ore with small sulfide dissemination; (2) sphalerite-pyrite chimney; (3) pyrite ore; (4) sulfide veinlets in strongly altered rock; and (5) pyrite megacrystals in strongly altered rock. The analyses revealed that the trace element distribution is regulated by the occurrence mode of the ore, and within each ore, by the crystal structure. The distribution suggests that the hydrothermal system for kuroko ore formation is quite heterogeneous and its chemistry is controlled by local factors such as difference in temperature, and that in-situ PIXE analyses are essential for effective beneficiation strategy for the rare-metals from kuroko-type ore. (authors). 10 refs., 1 tab.

  16. Mining remittances corresponding to metalliferous ores: regulation and budget impact

    Directory of Open Access Journals (Sweden)

    N. Asaloș

    2016-04-01

    Full Text Available Economic statistics and forecasting show that Romania has a very favourable potential as far as the metalliferous ores are concerned. As these are owned by the state, once they are allowed to be exploited, they generate considerable amounts for the consolidated public budget. The present paper is meant to conduct a synthetic analysis on the topic of mining remittances from an economic perspective, by considering the juridical framework of capitalizing deposits of ferrous and non-ferrous ores, correlated with the general regulations concerning property and the specific existing regulations of the EU and of the countries that have experience and potential in the mining sector.

  17. Bioleaching of copper oxide ore by Pseudomonas aeruginosa

    Science.gov (United States)

    Shabani, M. A.; Irannajad, M.; Azadmehr, A. R.; Meshkini, M.

    2013-12-01

    Bioleaching is an environmentally friendly method for extraction of metal from ores. In this study, bioleaching of copper oxide ore by Pseudomonas aeruginosa was investigated. Pseudomonas aeruginosa is a heterotrophic bacterium that can produce various organic acids in an appropriate culture medium, and these acids can operate as leaching agents. The parameters, such as particle size, glucose percentage in the culture medium, bioleaching time, and solid/liquid ratio were optimized. Optimum bioleaching conditions were found as follows: particle size of 150-177 μm, glucose percentage of 6%, bioleaching time of 8 d, and solid/liquid ratio of 1:80. Under these conditions, 53% of copper was extracted.

  18. A novel optical granulometry algorithm for ore particles

    Directory of Open Access Journals (Sweden)

    Junhao Y.

    2010-01-01

    Full Text Available This paper proposes a novel algorithm to detect the particle size distribution of ores with irregular shapes and dim edges. This optical granulometry algorithm is particularly suitable for blast furnace process control, so its result can be used directly as a reliable basis for control system dynamics optimization. The paper explains the algorithm and its concept, as well as its method, which consists of five steps to detect ore granularity and distribution. A series of comparative experiments under industrial environments proved that this novel algorithm, compared with conventional ones, improves the accuracy of granulometry.

  19. ECONOMIC EVALUATION OF GOLD-ORE DUMP REPROCESSING EFFICIENCY

    Directory of Open Access Journals (Sweden)

    N. Y. Samsonov

    2010-06-01

    Full Text Available An economic projection is presented in the paper on the heap leaching technology for extracting a residual gold from the gold-ore dumps accumulated at the exploited or closed gold mines. A brief analysis is performed on the legal status of use this source of raw materials, availability and efficiency of the heap leaching method are reviewed, and the potential users of this method are assessed. An investment plan is created for involving anthropogenic dumps of gold-raw materials at one of the ore deposits in Siberia (heap complex of the North-Western flank of the Sovetskoye minefield, Krasnoyarsk region, North-Yenisey area.

  20. Bioleaching of copper oxide ore by P seudomonas aeruginosa

    Institute of Scientific and Technical Information of China (English)

    MA Shabani; M Irannajad; AR Azadmehr; M Meshkini

    2013-01-01

    Bioleaching is an environmentally friendly method for extraction of metal from ores. In this study, bioleaching of copper oxide ore by Pseudomonas aeruginosa was investigated. Pseudomonas aeruginosa is a heterotrophic bacterium that can produce various organic acids in an appropriate culture medium, and these acids can operate as leaching agents. The parameters, such as particle size, glucose percentage in the culture medium, bioleaching time, and solid/liquid ratio were optimized. Optimum bioleaching conditions were found as follows: particle size of 150-177 μm, glucose percentage of 6%, bioleaching time of 8 d, and solid/liquid ratio of 1:80. Under these conditions, 53%of copper was extracted.

  1. Influences of ore formation on biomarkers in the Kupferschiefer from the Lubin mine, Poland

    Institute of Scientific and Technical Information of China (English)

    SUN Yuzhuang; CHEN Jianping; LIN Mingyue; MENG Zhiqiang; ZHANG Hongjian

    2005-01-01

    Molecular biomarkers are the important maturity parameters for sedimentary organic matter. They have also been widely used for determining the maturity of organic matter in ore deposits. However, during the study of organic matter in the Kupferschiefer from the Lubin mine, it had been found that the biomarkers were influenced by sulfide formation. In order to probe into the degree of influence on biomarkers, seven samples collected from a Kupferschiefer section from the Lubin mine were analyzed by various geochemical methods. The results indicated that in the samples with higher copper contents, the values of biomarkers are lower than in the samples with lower copper contents. In highly mineralized samples, hydrogen donation for thermochemical sulfate reduction (TSR) occurred in alkylated phenanthrenes and naphthalenes, leading to the decrease of 12 biomarker parameters during the Kupferschiefer mineralization.

  2. Assessment of soda ash calcination treatment of Turkish trona ore

    Directory of Open Access Journals (Sweden)

    Gezer Sibel

    2016-01-01

    Full Text Available Trona is relatively rare, non-metallic mineral, Na2CO3 · NaHCO3 · 2H2O. The pure material contains 70.3% sodium carbonate and by calcination the excess CO2 and water can be driven off, yielding natural soda ash. The terms soda ash and sodium carbonate are used interchangeably. Trona calcining is a key process step in production of soda ash (sodium carbonate anhydrate from the relatively cheap trona ore. The calcination reaction may proceeds in a sequence of steps. Depending on the conditions, it may result in formation of either sodium carbonate monohydrate (Na2CO3 · H2O, sodium sesquicarbonate or weigschederite (Na2CO3 · 3NaHCO3. The Beypazarı Turkish trona deposit is the second largest deposit in the world with the content of 84% trona. The decomposition of trona appeared to be a single stage process across the temperature range studied (150-200 °C with the representative samples of different size fractions in the draught up metallurgical furnace. The optimum particle size and calcination time were −6.35 mm and 30 minutes, respectively, at calcination temperature of 175 °C in a metallurgical furnace. Microwave-induced dry calcination of trona was possible and 5 minutes of calcination time at a power level of 900 was sufficient for complete calcination of −6.35 mm feed. This includes short time calcinations with the goal of improving economics and simplifying the thermal process.

  3. Determination of tin in cassiterite ores by colorimetry of iodometry; Determinacion de Estano en minerales y productos de concentracion

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Hernandez, B.

    1972-07-01

    The analytical methods are described far the determination of tin in cassiterite ores. The gallein-colorimetric method is described for determining small amounts of tin, covering the 0,01-0,5 per cent range. The sample is decomposed by heating with ammonium iodide, and tin is analyzed colorimetrically by means of it s complex with gallein. The final measure may be brought about either visually or spectrophotometrically at 525 nm. (Author)

  4. Environmental nuclear-geophysical ore monitoring in mines of Corporation Kazakhmys PLC.

    Science.gov (United States)

    Yefimenko, Sergei; Yefimenko, Olga; Makarov, Dmitriy

    2014-01-01

    An environmental monitoring of ore composition in complex deposits of Kazakhstan (the Zhezkazgan, Kusmuryn, Artemjevsk, Kounrad, Taskura and Zhaman-Aibat deposits) is carried out using EDXRF spectrometers RPP-12, RLP-21 and RLP-21T. The monitoring of ore concentrates in Satpaev, Balkhashsk and Zhezkazgan processing plants and in Zhezkazgan copper smelter continues at present time. The monitoring suggests data on new promising elements and environmental pollutants in ores and new trends in distribution of bound elements in ores.

  5. 26 CFR 1.272-1 - Expenditures relating to disposal of coal or domestic iron ore.

    Science.gov (United States)

    2010-04-01

    ... domestic iron ore. 1.272-1 Section 1.272-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... relating to disposal of coal or domestic iron ore. (a) Introduction. Section 272 provides special treatment... sometimes referred to as a “coal royalty contract” or “iron ore royalty contract”) for the disposal of coal...

  6. 75 FR 68788 - Ore Knob Mine Superfund Site; Jefferson, Ashe County, North Carolina; Notice of Settlement

    Science.gov (United States)

    2010-11-09

    ... Doc No: 2010-28260] ENVIRONMENTAL PROTECTION AGENCY [Docket EPA-RO4-SFUND-2010-0893, FRL-9223-8] Ore... Protection Agency has entered into a settlement for reimbursement of past response costs concerning the Ore..., identified by Docket ID No. EPA-RO4- SFUND-2010-0893 or Site name Ore Knob Mine Superfund Site by one of...

  7. IMPACT: How ORE Findings Have Affected Decisions in Austin and Beyond.

    Science.gov (United States)

    Wilkinson, David, Ed.; Ligon, Glynn, Ed.

    Over the years, findings of the Office of Research and Evaluation (ORE) of the Austin (Texas) Independent School District (AISD) have had a significant impact on decisions made in the district and sometimes beyond it. The ORE's impact in the AISD is reviewed in 16 areas. Some of the major findings are summarized: (1) ORE studies of retention in…

  8. 40 CFR 440.80 - Applicability; description of the vanadium ore subcategory.

    Science.gov (United States)

    2010-07-01

    ... vanadium ore subcategory. 440.80 Section 440.80 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Vanadium Ore Subcategory (Mined Alone and Not as a Byproduct) § 440.80 Applicability; description of the vanadium...

  9. 28 CFR 79.62 - Criteria for eligibility for claims by ore transporters.

    Science.gov (United States)

    2010-07-01

    ... ore transporters. 79.62 Section 79.62 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CLAIMS UNDER THE RADIATION EXPOSURE COMPENSATION ACT Eligibility Criteria for Claims by Ore Transporters § 79.62 Criteria for eligibility for claims by ore transporters. To establish eligibility for...

  10. 28 CFR 79.63 - Proof of employment as an ore transporter.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Proof of employment as an ore transporter... RADIATION EXPOSURE COMPENSATION ACT Eligibility Criteria for Claims by Ore Transporters § 79.63 Proof of employment as an ore transporter. (a) The Department will accept, as proof of employment for the time...

  11. Development of the Method of Bacterial Leaching of Metals out of Low-Grade Ores, Rocks, and Industrial Wastes Using Neutron Activation Analysis

    CERN Document Server

    Tsertsvadze, L A; Petriashvili, Sh G; Chutkerashvili, D G; Kirkesali, E I; Frontasyeva, M V; Pavlov, S S; Gundorina, S F

    2001-01-01

    The results of preliminary investigations aimed at the development of an economical and easy to apply technique of bacterial leaching of rare and valuable metals out of low-grade ores, complex composition ores, rocks, and industrial wastes in Georgia are discussed. The main groups of microbiological community of the peat suspension used in the experiments of bacterial leaching are investigated and the activity of particular microorganisms in the leaching of probes with different mineral compositions is assessed. The element composition of the primary and processed samples was investigated by the epithermal neutron activation analysis method and the enrichment/subtraction level is estimated for various elements. The efficiency of the developed technique to purify wastes, extract some scrace metals, and enrich ores or rocks in some elements, e.g. Au, U, Th, Cs, Sr, Rb, Sc, Zr, Hf, Ta, Gd, Er, Lu, Ce, etc., is demonstrated.

  12. 40 CFR 61.53 - Stack sampling.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Stack sampling. 61.53 Section 61.53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL... sampling. (a) Mercury ore processing facility. (1) Unless a waiver of emission testing is obtained...

  13. Neutron shielding qualities and gamma ray buildup factors of concretes containing limonite ore

    Energy Technology Data Exchange (ETDEWEB)

    Oto, Berna, E-mail: bpekgoz@yahoo.com [Department of Physics, Faculty of Science, Yüzüncü Yıl University, 65080 Van (Turkey); Yıldız, Nergiz [Department of Physics, Faculty of Science, Yüzüncü Yıl University, 65080 Van (Turkey); Korkut, Turgay [Department of Nuclear Energy Engineering, Faculty of Engineering, Sinop University, 57000 Sinop (Turkey); Kavaz, Esra [Department of Physics, Faculty of Science, Ataturk University, 25240 Erzurum (Turkey)

    2015-11-15

    Highlights: • Macroscopic removal cross-sections (Σ{sub R}, cm{sup −1}) have been determined experimentally and theoretically for concrete samples. • EABF and EBF of the concrete samples has been determined using the Geometric Progression (G-P) approximation. • Penetration depth and energy dependence of the buildup factors evaluated. • FCL is good shielding material for neutron and gamma radiation. - Abstract: Neutron dose transmissions for fast neutrons produced by 5.486 MeV alpha particles on beryllium are measured in concrete samples with and without limonite ore to investigate their neutron shielding qualities. Using measured values, macroscopic removal cross-sections (Σ{sub R}, cm{sup −1}) have been determined experimentally and also Σ{sub R}values have been calculated theoretically using the elemental composition of the concrete mixes. The best neutron shielding property of concrete sample containing 100% limonite ore (FCL: fine and coarse limonite) was found. Additionally, energy absorption buildup factor (EABF) and exposure buildup factor (EBF) of concrete sample were calculated using the five-parameter Geometric Progression (G-P) approximation in the energy range of 0.015–15 MeV for penetration depths up to 40 mean free path (mfp). The incident photon energy and penetration depth dependence of buildup factors were examined. Finally, we observed that concrete samples have maximum values of buildup factors in the intermediate energy region around 0.1–0.3 MeV. FCL has the minimum values of both of the buildup factors. FCL has the excellent gamma shielding properties compared to the concrete samples.

  14. Sampling and analysis of chemical element concentration distribution in rock units and orebodies

    National Research Council Canada - National Science Library

    F P Agterberg

    2012-01-01

      Existing sampling techniques applied within known orebodies, such as sampling along mining drifts, yield element concentration values for larger blocks of ore if they are extended into their surroundings...

  15. Nonlinear Effects of Laser Surface Modification of Ore Minerals

    Directory of Open Access Journals (Sweden)

    N.A. Leonenko

    2015-12-01

    Full Text Available The effect of continuous laser radiation on complex ore minerals objects containing gold, not extracted by monerd methods was investigated. It was established the formation of different structural surfaces of gold, revealed general patterns of sintering and concentration of sub-micron gold.

  16. Challenges facing the North American iron ore industry

    Science.gov (United States)

    Jorgenson, J.D.

    2006-01-01

    Summary: This report is derived from a presentation the author presented in late September at the Iron Ore 2005 Conference sponsored by The Australasian Institute of Mining and Metallurgy and held in Fremantle, Western Australia. Some slight revisions have been made for the new audience.

  17. Reduction Mechanism of Chromite Ore in Blast Furnace

    Institute of Scientific and Technical Information of China (English)

    LI Yi-wei; DING Wei-zhong; LU Xiong-gang; XU Kuang-di

    2004-01-01

    The structural changes and reduction degree of chromite ore in blast furnace were studied by optical micrograph analysis, scanning electron microscope (SEM) and energy dispersive X-ray analysis (EDXA). The smelting reduction mechanism of chromite in blast furnace was primarily discussed.

  18. Technogenic hydrogeochemical anomalies of tungsten deposits in Kykylbey ore region

    Institute of Scientific and Technical Information of China (English)

    Leonid V.Zamana; Larisa P.Chechel

    2004-01-01

    Peculiarities of the tungsten deposits drainage flow chemical composition formation, the development of which was ceased almost 40 years ago, have been considered. Migration peculiarities of ore components have been covered, and forms of their migration have been calculated. Inertial characteristics of the surface flow contamination are shown.

  19. When People Talk, AISD Listens! ORE Districtwide Surveys, 1983.

    Science.gov (United States)

    Austin Independent School District, TX. Office of Research and Evaluation.

    The Austin Independent School District (AISD) Office of Research and Evaluation (ORE) conducts three surveys to contribute to more informed and better decision-making. The Questions for Teachers and Questions for Administrators surveys are both sent out annually to determine the attitudes of District staff on issues of importance districtwide. The…

  20. ORE's GENeric Evaluation SYStem: GENESYS 1988-89.

    Science.gov (United States)

    Baenen, Nancy; And Others

    GENESYS--GENeric Evaluation SYStem--is a method of streamlining data collection and evaluation through the use of computer technology. GENESYS has allowed the Office of Research and Evaluation (ORE) of the Austin (Texas) Independent School District to evaluate a multitude of contrasting programs with limited resources. By standardizing methods and…

  1. Rock Smelting of Copper Ores with Waste Heat Recovery

    Science.gov (United States)

    Norgate, Terry; Jahanshahi, Sharif; Haque, Nawshad

    It is generally recognised that the grades of metallic ores are falling globally. This trend can be expected to increase the life cycle-based energy requirement for primary metal production due to the additional amount of material that must be handled and treated in the mining and mineral processing stages of the metal production life cycle. Rock (or whole ore) smelting has been suggested as a possible alternative processing route for low grade ores with a potentially lower energy intensity and environmental impact than traditional processing routes. In this processing route, the beneficiation stage is eliminated along with its associated energy consumption and greenhouse gas emissions, but this is partially offset by the need for more solid material to be handled and heated up to smelting temperatures. A life cycle assessment study was carried out to assess the potential energy and greenhouse gas benefits of a conceptual flowsheet of the rock smelting process, using copper ore as an example. Recovery and utilisation of waste heat in the slag (via dry slag granulation) and offgas streams from the smelting step was also included in the study, with the waste heat being utilised either for thermal applications or electricity generation.

  2. Method and set-up for uranium ore sorting

    Energy Technology Data Exchange (ETDEWEB)

    Dragulescu, E.; Ivascu, M.; Popescu, D.; Semenescu, G. (Institutul de Fizica si Inginerie Nucleara, Bucharest (Romania)); Gherea, Gh. (Intreprinderea metalelor rare, Bucuresti (Romania)); Draga, Z.; Funaru, Gh. (Exploatarea miniera Oravita, Oravita (Romania))

    1981-01-01

    A method was studied for uranium ore sorting. After the discussion of the principle, some particular conditions of the sorting are pointed out. A radiometric assembly is described and some results obtained on the simulator and in industrial conditions are reported.

  3. Hemimorphite Ores: A Review of Processing Technologies for Zinc Extraction

    Science.gov (United States)

    Chen, Ailiang; Li, Mengchun; Qian, Zhen; Ma, Yutian; Che, Jianyong; Ma, Yalin

    2016-10-01

    With the gradual depletion of zinc sulfide ores, exploration of zinc oxide ores is becoming more and more important. Hemimorphite is a major zinc oxide ore, attracting much attention in the field of zinc metallurgy although it is not the major zinc mineral. This paper presents a critical review of the treatment for extraction of zinc with emphasis on flotation, pyrometallurgical and hydrometallurgical methods based on the properties of hemimorphite. The three-dimensional framework structure of hemimorphite with complex linkage of its structural units lead to difficult desilicification before extracting zinc in the many metallurgical technologies. It is found that the flotation method is generally effective in enriching zinc minerals from hemimorphite ores into a high-grade concentrate for recovery of zinc. Pure zinc can be produced from hemimorphite or/and willemite with a reducing reagent, like methane or carbon. Leaching reagents, such as acid and alkali, can break the complex structure of hemimorphite to release zinc in the leached solution without generation of silica gel in the hydrometallurgical process. For optimal zinc extraction, combing flotation with pyrometallurgical or hydrometallurgical methods may be required.

  4. Detection of diamond in ore using pulsed laser Raman spectroscopy

    CSIR Research Space (South Africa)

    Lamprecht, GH

    2007-10-01

    Full Text Available The viability of using pulsed laser excited Raman spectroscopy as a method for diamond detection from ore, has been investigated. In this method the spontaneous Stokes Raman signal is used as indicator of diamond, and a dual channel system...

  5. Natural Ores as Oxygen Carriers in Chemical Looping Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Hanjing; Siriwardane, Ranjani; Simonyi, Thomas; Poston, James

    2013-08-01

    Chemical looping combustion (CLC) is a combustion technology that utilizes oxygen from oxygen carriers (OC), such as metal oxides, instead of air to combust fuels. The use of natural minerals as oxygen carriers has advantages, such as lower cost and availability. Eight materials, based on copper or iron oxides, were selected for screening tests of CLC processes using coal and methane as fuels. Thermogravimetric experiments and bench-scale fixed-bed reactor tests were conducted to investigate the oxygen transfer capacity, reaction kinetics, and stability during cyclic reduction/oxidation reaction. Most natural minerals showed lower combustion capacity than pure CuO/Fe{sub 2}O{sub 3} due to low-concentrations of active oxide species in minerals. In coal CLC, chryscolla (Cu-based), magnetite, and limonite (Fe-based) demonstrated better reaction performances than other materials. The addition of steam improved the coal CLC performance when using natural ores because of the steam gasification of coal and the subsequent reaction of gaseous fuels with active oxide species in the natural ores. In methane CLC, chryscolla, hematite, and limonite demonstrated excellent reactivity and stability in 50-cycle thermogravimetric analysis tests. Fe{sub 2}O{sub 3}-based ores possess greater oxygen utilization but require an activation period before achieving full performance in methane CLC. Particle agglomeration issues associated with the application of natural ores in CLC processes were also studied by scanning electron microscopy (SEM).

  6. Valorization of mining waste from Ouenza iron ore mine (eastern Algeria

    Directory of Open Access Journals (Sweden)

    Abdelaziz Idres

    Full Text Available Abstract The present article is devoted to the development of a hematite-poor ore mine in Ouenza, which does not meet the steelmaker's requirements. Significant volumes are stored at the pithead of the mine, and the reserves are estimated at over 100 million tones. This enormous quantity of mining waste occupies an important space and poses a real threat to the environment as well as for the mining city of Ouenza. In order to solve these socio-economic and environmental problems, a sustainable development and a better quality of life for inhabitants of this region is needed. For this, representative samples were taken at the level of the dumps. Taking into account the natural characteristics of the stock namely; mineralogical composition, iron content, particle size of the rock mass, as well as the release mesh of iron minerals from the gangue. Firstly, tests are conducted on the recovery by radiometric separation of iron-rich pieces and graded. Then the rest of the ore was subjected to mechanical preparation followed by enrichment, which will be the subject of another study. The research is conducted on samples to determine the optimal parameters of the g-rays absorption tested by radiometry; these parameters were the velocity of the conveyor belt and the time of exposure to g-rays. The obtained results by this valorization process are very significant: iron content 53.5% and 8.3% recovery.

  7. Shining a light on oil sands production : spectroscopy could bring flash of insight to ore processing

    Energy Technology Data Exchange (ETDEWEB)

    Zlotnikov, D.

    2010-09-15

    Oil sands are a mixture of silts, sands and clay, and the variability poses challenges to surface mine operators. A professor of Earth and Atmospheric Sciences at the University of Alberta has been working on a spectroscopy project to provide the oil sand industry with real-time ore composition and particle size readings from the mine face. These can then be used to adjust processing conditions at the extraction plant or froth treatment facility, ensuring optimal recovery levels and smooth operation. Developing a spectrographic fingerprint of an ore sample involves shining a very narrow wavelength of light at the sample, recording the intensity of reflected light and repeating the process across a range of wavelengths. The challenges of putting the spectroscopic equipment at the mine site were described. The project is 1 of the more than 20 projects currently at the Centre for Oil Sands Innovation (COSI), a partnership between Imperial Oil and the University of Alberta. Imperial contributed $10 million in funding over the following 5 years, with the governments of Alberta and Canada contributing additional funds. Imperial Oil is not the only beneficiary of COSI research, as all work that comes out of COSI is ultimately published. 1 fig.

  8. Coupling of anionic wetting agents to dust of sulfide ores by dropping liquid method

    Institute of Scientific and Technical Information of China (English)

    WU Chao; OU Jia-cai; ZHOU Bo

    2005-01-01

    By using the experimental approach of dropping liquid, the coupling of three anionic wetting agents with ten dust samples of sulfide ores was studied, and particularly the wetting effects of the wetting agents on the sulfide dust influenced by factors of agent concentration and sulfate additive in the wetting agent solutions were investigated. The results show that when the solution temperature is about 20 ℃, all the selected wetting agents are effective to most dust samples, but the effect is different. Wetting agents are more effective to the dust which is difficult to be wetted. Wetting agent solution with sodium sulfate can improve the wetting ability of sulfide dust. For sodium dodecyl benzene sulfonate, the suitable concentration of sodium sulfate is 1-2 mmol/L. The cost of wetting agents can be reduced because the sodium sulfate is much cheaper than many surfactants. Since the dust of sulfide ores is composed of various minerals and elements, the whole effect of depressing dust should be considered while innovating a wetting agent.

  9. Manganese ore tailing: optimization of acid leaching conditions and recovery of soluble manganese.

    Science.gov (United States)

    Santos, Olívia de Souza Heleno; Carvalho, Cornélio de Freitas; Silva, Gilmare Antônia da; Santos, Cláudio Gouvêa Dos

    2015-01-01

    Manganese recovery from industrial ore processing waste by means of leaching with sulfuric acid was the objective of this study. Experimental conditions were optimized by multivariate experimental design approaches. In order to study the factors affecting leaching, a screening step was used involving a full factorial design with central point for three variables in two levels (2(3)). The three variables studied were leaching time, concentration of sulfuric acid and sample amount. The three factors screened were shown to be relevant and therefore a Doehlert design was applied to determine the best working conditions for leaching and to build the response surface. By applying the best leaching conditions, the concentrations of 12.80 and 13.64 %w/w of manganese for the global sample and for the fraction -44 + 37 μm, respectively, were found. Microbeads of chitosan were tested for removal of leachate acidity and recovering of soluble manganese. Manganese recovery from the leachate was 95.4%. Upon drying the leachate, a solid containing mostly manganese sulfate was obtained, showing that the proposed optimized method is efficient for manganese recovery from ore tailings.

  10. Novel Binders and Methods for Agglomeration of Ore

    Energy Technology Data Exchange (ETDEWEB)

    S. K. Kawatra; T. C. Eisele; K. A. Lewandowski; J. A. Gurtler

    2006-09-30

    Heap leaching is one of the methods being used to recover metal from low grade ore deposits. The main problem faced during heap leaching is the migration of fine grained particles through the heap, forming impermeable beds which result in poor solution flow. The poor solution flow leads to less contact between the leach solution and the ore, resulting in low recovery rates. Agglomeration of ore into coarse, porous masses prevents fine particles from migrating and clogging the spaces and channels between the larger ore particles. Currently, there is one facility in the United States which uses agglomeration. This operation agglomerates their ore using leach solution (raffinate), but is still experiencing undesirable metal recovery from the heaps due to agglomerate breakdown. The use of a binder, in addition to the leach solution, during agglomeration would help to produce stronger agglomerates that did not break down during processing. However, there are no known binders that will work satisfactorily in the acidic environment of a heap, at a reasonable cost. As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. Increasing copper recovery in heap leaching by the use of binders and agglomeration would result in a significant decrease in the amount of energy consumed. Assuming that 70% of all the leaching heaps would convert to using agglomeration technology, as much as 1.64*10{sup 12} BTU per year would be able to be saved if a 25% increase in copper recovery was experienced, which is equivalent to saving approximately 18% of the energy currently being used in leaching heaps. For every week a leach cycle was decreased, a savings of as much as 1.23*10{sup 11} BTU per week would result. This project has identified several acid-resistant binders and agglomeration procedures. These binders and experimental procedures will be able to be used for use in improving the energy efficiency of

  11. Telescoping ore targets by geochemical exploration at multiple scales in Eastern Yunnan Pt geochemical province,southwestern China

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Platinum has been one of the highly needed mineral resources in China.The geochemical exploration at two survey scales was applied in telescoping ore targets for the first time in Eastern Yunnan Pt geochemical province that was delineated using Pt data from flood plain sediments with extra-low sampling density.Our study was based on the delineations and assessments of both regional and local Pt anomalies using the Pt data by analyzing with C-OES the composite samples with two sampling densities.The composite samples were obtained by recomposing at two sampling densities the original stream sediment samples collected by the National Geochemical Mapping Project.Semivariograms were used to quantitatively describe the variability of Pt anomalies and further analyze the factors controlling the variability.Pt resource potentials of both the regional Pt anomalies and the local Pt anomalies in the study area were estimated based on the geochemical block methods,respectively.It comes to the conclusions as follows.(1) From the regional to local Pt anomaly,the factors controlling their variability from the deep seated faults-basalts turn into the basalts-branch faults,which suggest that Semivariograms could identify the geological factors controlling the variability of the Pt anomalies identified by the Pt data from the stream sediments with different sampling densities.(2) There exist two types of Pt anomalies in the study area.One is those displaying at sampling densities,and its average Pt concentration significantly increases with sampling density increasing.The other is getting weaker and/or disappears with sampling density increasing.This shows that TOTGEMS could gradu-ally eliminate non-ore anomalies and keep ore anomalies.(3) The average Pt concentration of the local Pt anomaly blocks delineated using Pt data from stream sediments with sampling density of one composite per 16 km2 is twice as much as that of the regional Pt anomaly blocks delineated using Pt data from

  12. Effects of Mineral Composition and Microstructure on Crack Resistance of Sintered Ore

    Institute of Scientific and Technical Information of China (English)

    YING Zi-wei; JIANG Mao-fa; XU Li-xian

    2006-01-01

    Vickers indentation test was used to study the effects of mineral composition and microstructure on crack resistance of sintered ore, and the initiation and propagation of cracks in different minerals contained in sintered ore were examined. The results indicate that the microstructure of calcium ferrites is a major factor influencing crack resistance of sintered ore. Finer grain size of calcium ferrite will lead to higher cracking threshold and better crack resistance of sintered ore. The formation of calcium ferrite with fine grain size during sintering process is favorable for crack resistance of sintered ore.

  13. Fundamentals of fast reduction of ultrafine iron ore at low temperature

    Institute of Scientific and Technical Information of China (English)

    Pei Zhao; Peimin Guo

    2008-01-01

    Fundamentals on the fast reduction of ultrafine iron ore at low temperature, including characterization of ultrafine ore, de- oxidation thermodynamics of stored-energy ultrafine ore, kinetics of iron ore deoxidation, and deoxidation mechanism, etc., and a new ironmaking process are presented in this article. Ultrafine ore concentrate with a high amount of stored energy can be produced by mechanical milling, and can be dcoxidated fast below 700℃ by either the coal-based or gas-based process. This novel process has some advantages over others: high productivity, low energy consumption, and environmental friendliness.

  14. Explosion-assisted preparation of dispersed gold-bearing different-grade ore for selective mining

    Science.gov (United States)

    Trubachev, AI; Zykov, NV

    2017-02-01

    It is found that there are transient zones (between quality and off-quality ore areas) with the respective content of useful component in an ore body, and a variant of explosive treatment of such zones before the selective mining is put forward. Practicability of two processing technologies is evaluated: processing of high-grade and low-grade ore from the transient zones and heap leaching of metals from the low-grade and impoverished ore. Open mining technology is conventional truck-and-shovel scheme, with distributed ore flows to processing plant and (or) to heap leaching, which generally enhances the mine efficiency.

  15. Feasibility Studies for Production of Pellet Grade Concentrate from Sub Grade Iron Ore Using Multi Gravity Separator

    Science.gov (United States)

    Rao, Gottumukkala Venkateswara; Markandeya, R.; Kumar, Rajan

    2017-07-01

    An attempt has been made to utilise Sub Grade Iron Ore by producing pellet grade concentrate from Deposit 5, Bacheli Complex, Bailadila, Chhattisgarh, India. The `as received' Run of Mine (ROM) sample assayed 40.80% Fe, 40.90% SiO2. Mineralogical studies indicated that the main ore mineral is Hematite and lone gangue mineral is Quartz. Mineral liberation studies indicated that, the ore mineral Hematite and gangue mineral Quartz are getting liberated below 100 microns. The stage crushed and ground sample was subjected to concentration by using a Multi Gravity Separator (MGS). Rougher Multi Gravity Separation (MGS) experimental results were optimised to recover highest possible iron values. A concentrate of 55.80% Fe with a yield of 61.73% by weight with a recovery of 84.42% Iron values was obtained in rougher MGS concentrate. Further experiments were carried out with rougher MGS concentrate to produce a concentrate suitable for commercial grade pellet concentrate. It was proved that a concentrate assaying 66.67% Fe, 3.12% SiO2 with an yield of 45.08% by weight and with a recovery of 73.67% iron values in the concentrate.

  16. Discussion on grades of raw ores and raw ores for cyanidation in ore-dressing plant of Longtoushan Gold Mine%龙头山金矿选矿厂原矿品位、氰原品位问题探讨

    Institute of Scientific and Technical Information of China (English)

    姚让彪; 林取乾

    2014-01-01

    针对贵港市金地矿业有限责任公司龙头山金矿选矿厂重选+氰化工艺流程因存在粗粒明金、矿样代表性差、部分金提前浸出,导致原矿品位、氰原品位实际值与理论值存在误差,金属难以平衡的问题。通过改进措施、选取合适的取样点,确定了一种较为合理的计算方法,使其实际值与理论值基本相符。%There are many defects in gravity separation -cyanidation process currently used in ore-dressing plant of Longtoushan Gold Mine,Guigang Jindi mining company,that are the presence of coarse-grained visible gold,poor representativeness of samples and early leached gold ,making the actual value of the grades of raw ores and raw ores for cyanidation deviate from the theoretical one and resulting in the imbalance between metal .To deal with that ,optimiza-tion measures are taken ,proper sampling sites are selected and thus a fairly reasonable calculation method is obtained , making the actual value of the grades consistent with the theoretical one .

  17. China's emergence as the world's leading iron-ore-consuming country

    Science.gov (United States)

    Kirk, W.S.

    2004-01-01

    China has become the leading iron ore consuming nation, and, based on recent steel production capacity increases and plans for more, its consumption will almost certainly to continue to grow. China's iron ore industry, however, faces a number of problems. China's iron ore is low-grade, expensive to process, and its mines are being depleted. For many Chinese steelmakers, particularly in the coastal regions, the delivered cost of domestic iron ore, is more than the delivered cost of foreign ore. Thus China's iron ore imports are expected to increase. As China's growth continues, it will almost certainly surpass Japan to become the leading iron ore importing country as well. Without China's increasing appetite for iron ore, the world iron ore market would be flat or declining. China's recent imports largely offset the slump in demand in North America and Europe. China is regarded by the iron ore industry as the growth sector for the next decade. Although Chinese imports are expected to continue their rapid increase and imports in other Asian countries are expected to continue growing, there appears to be enough greenfield and expansion projects to meet future demand for iron ore worldwide. Present suppliers of iron ore, Australia, Brazil, India, and South Africa, will probably be the chief beneficiaries of China's increasing consumption of iron ore. How long China can continue its extraordinary growth is the primary issue for the future of the iron ore industry. Based on the number and size of planned blast furnaces it appears that China's growth could continue for several more years. ?? 2004 Taylor and Francis.

  18. Pretreatment of copper-bearing refractory gold ores by bio-heap leaching

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The refractory gold ores associated with rich copper and trapped in pyrite and quartz were studied. With conventional technique (all-sliming cyanidation), the gold recovery rate is only 51.78%. To eliminate the negative effects of copper and pyrite on cyanidation and increase the gold recovery rate, the investigation on bio-heap leaching pretreatment was made, by which Cu would be dissolved and gold would be liberated from pyrite. The experiment adopted mixed bacteria, mainly Thiobacillus ferrooxidan (named T. f1), as the bacterial catalyst for bio-preconditioning and was carried out in a PVC column with a diameter of 20 cm and a height of 1.3 m loaded with gold ores. The temperature was controlled between 28 and 30℃, the pH value was kept between 2.0-2.5,and the flux of sprinkling bacterial liquid was maintained 0.80 L/h. After 45-day's bio-oxidization, among the samples sizing from 0to 5 mm, the oxidation rates of Cu, Fe and S were respectively 44.62%, 28.16% and 25.46%, and the gold recovery rate by cyaniding increased to 80.35%. The bio-heap leaching pretreatment can therefore effectively dissolve Cu and liberate gold from pyrite and lead to the increase of gold extraction.

  19. Airway inflammation in iron ore miners exposed to dust and diesel exhaust.

    Science.gov (United States)

    Adelroth, E; Hedlund, U; Blomberg, A; Helleday, R; Ledin, M-C; Levin, J O; Pourazar, J; Sandström, T; Järvholm, B

    2006-04-01

    The aim of the present study was to investigate if underground miners exposed to dust and diesel exhaust in an iron ore mine would show signs of airway inflammation as reflected in induced sputum. In total, 22 miners were studied, once after a holiday of at least 2 weeks and the second time after 3 months of regular work. Control subjects were 21 "white-collar" workers. All subjects completed a questionnaire regarding medical and occupational history, and underwent lung function testing and induced sputum collection. Total and differential cell counts and analyses of the fluid phase of the induced sputum were performed. Sampling of personal exposure to elemental carbon, nitrogen dioxide and inhalable dust was recorded. The average concentrations of inhalable dust, nitrogen dioxide and elemental carbon were 3.2 mg.m-3, 0.28 mg.m-3 and 27 microg.m-3, respectively. Miners had increased numbers of inflammatory cells, mainly alveolar macrophages and neutrophils, and increased concentrations of fibronectin, metalloproteinase-9 and interleukin-10 in induced sputum compared with controls. In conclusion, miners in an underground iron ore mine demonstrated persistent airway inflammation that was as pronounced after a 4-week holiday as after a 3-month period of work underground in the mine.

  20. Biological Effects of Cloth Containing Specific Ore Powder in Patients with Pollen Allergy

    Institute of Scientific and Technical Information of China (English)

    Suni LEE; YasuzoKIRITA; YoshioFUJII; TakemiOTSUKI; HitoshiOKAMOTO; ShokoYAMAMOTO; TamayoHATAYAMA; HidenoriMATSUZAKI; Naoko KUMAGAI-TAKEI; KeiYOSHITOME; YasumitsuNISHIMURA; ToshiakiSATO

    2016-01-01

    ObjectiveThe custom-homebuilding company, Cosmic Garden Co. Ltd., located in Okayama City, Japan was established in 1997 and uses specific natural ore powder (SNOP) in wall materials and surveys customers in order to improve allergic symptoms. MethodsTo investigate the biological effects of SNOP, patients with a pollen allergy were recruited to stay in a room surrounded by cloth containing SNOP (CCSNOP), and their symptoms and various biological parameters were compared with those of individuals staying in a room surrounded by control non-woven cloth (NWC). Each stay lasted 60 min. Before and immediately after the stay, a questionnaire regarding allergic symptoms, as well as POMS (Profile of Mood Status) and blood sampling, was performed. Post-stay minus pre-stay values were calculated and compared between CCSNOP and NWC groups. ResultsResults indicated that some symptoms, such as nasal obstruction and lacrimation, improved, and POMS evaluation showed that patients were calmer following a stay in CCSNOP. Relative eosinophils, non-specific Ig E, epidermal growth factor, monocyte chemotactic protein-1, and tumor necrosis factor-α increased following a stay in CCSNOP. ConclusionThis ore powder improved allergic symptoms, and long-term monitoring involving 1 to 2 months may be necessary to fully explore the biological and physical effects of SNOP on allergic patients.

  1. Geostatistical Approach to Estimating the Gold Ore Characteristics and Gold Reserves: A Case Study Daksa Area, Quang Nam Province, Viet Nam

    Science.gov (United States)

    Luan Truong, Xuan; Luong Le, Van; Quang Truong, Xuan

    2015-04-01

    Daksa gold deposit is the biggest gold deposits in Vietnam. The Daksa geological structure complicated, distributed mainly metamorphosed sedimentary NuiVu formation (PR3-?1nv2). The sulfide gold ore bodies distributed in quartz schist, quartz - biotite related to faut and distribution wing anticline. The gold ore bodies form circuits, network circuits, circuits lenses; fill the cup surface layer of the developing northeast - southwest; is the less than or west longitude north - SE. The results show that, Au and accompanying elements (Ag, Pb and Zn) have correlated pretty closely. All of its consistent with the logarithmic distribution standard, in accordance with the law of distribution of content mineral rare. The structure functions have nugget effect and spherical models with show that Au and accompanying elements special variation are changes. Au contents shown local anisotropy, no clearly anisotropy (K=1,17) and weakly anisotropy (K=1,4). Intensity mineralization of the ore bodies are quite high with demand spherical conversion coefficient ranging from 0.49 to 0.75 and from 0.66 to 0.97 (for other body). With nugget effects, ore bodies shown that it is consistent with mineralization in the ore bodies study, ore erasable, micro vein, infilling fractures in quartz vein. All of variogram presents local anisotropy, indicated gold mineralization at study area has least two-mineralization stages, consistent with the analysis of mineralography samples. By the results of the structure function study, the authors present the system optimization for exploration deposit and used to evaluate gold reserves by Ordinary Kriging. High accuracy of Kriging estimation results are expressed in the minimum Kriging variance, by compare the results calculated by some other methods (such as distance inverse weighting method, ..) and specially compare to the results of a some blocks have been exploited. Key words: Geostat and gold deposits VN. Daksa and gold mineralization. Geostat

  2. EXPERIMENTAL STUDIES ON FELDSPAR ORE CONCENTRATION

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A series of Fe2O3-elimination experiments were conducted on feldspar samples from Tangshan Stone-powder Plant. These experimental methods include scrubbing desliming, flotation, rod milling and high gradient magnetic separation. Some technical factors of feldspar concentration and a new technological flow-sheet of ceramics raw material concentration were put forward.

  3. [Qualitative and quantitative analysis of various elements in chromite ore by ICP-AES].

    Science.gov (United States)

    Zhang, Yang; Zheng, Shi-li; Wang, Xiao-hui; Xu, Hong-bin; Zhang, Yi

    2010-01-01

    Kind of the elements in chromite ore was firstly determined by ICP-AES. Twenty nine elements, such as Cr, Fe, Al, Mg, Zn, Ca and Ni, were contained in the chromite sample based on the qualitative analysis. Then the contents of main elements Cr, Fe, Al, Mg, Ca, T, Si, Mn and V were measured. The chromite samples processing procedures have two steps, the first is decomposition by nitrate carbonate and sodium tetraborate at 950 degrees C for 30 min, then leaching by dilute hydrochloric acid at 80 degrees C for 10 min. The method showed satisfactory precision and accuracy with the RSDs between 0.48% and 2.05% and the recovery rates between 90.5% and 111.3%.

  4. The genesis of the base metal ore deposit from Herja

    Directory of Open Access Journals (Sweden)

    Gheorghe Damian

    2003-04-01

    Full Text Available The Herja ore deposit is one of the most known of the Baia Mare Neogene metallogenetic district and is associated with a complex stock of Pannonian age. The hydrothermal alterations associated with the mineralizations are represented by: the propylitization, the argillization, the phyllic and potassic alteration. The monoascenedant character of the mineralizations is predominant. The magmatic intrusions have been sequential placed and have represented the heat, metals and hydrothermal solutions source. In the first stages of mineralization the hydrothermal solutions contain predominantly magmatic water and in the final stages the water is of connate and meteoric origin. According to the structural magmatic control, to the mineralogical composition and to the hydrothermal alterations, the Herja ore deposits are of a low sulphidation epithermal systems type.

  5. Estimation of Springing Response for 550 000 DWT Ore Carrier

    Institute of Scientific and Technical Information of China (English)

    Christiaan Adika Adenya; Huilong Ren; Hui Li; Di Wang

    2016-01-01

    The desire to benefit from economy of scale is one of the major driving forces behind the continuous growth in ship sizes. However, models of new large ships need to be thoroughly investigated to determine the carrier’s response in waves. In this work, experimental and numerical assessments of the motion and load response of a 550,000 DWT ore carrier are performed using prototype ships with softer stiffness, and towing tank tests are conducted using a segmented model with two schemes of softer stiffness. Numerical analyses are performed employing both rigid body and linear hydroelasticity theories using an in-house program and a comparison is then made between experimental and numerical results to establish the influence of stiffness on the ore carrier’s springing response. Results show that softer stiffness models can be used when studying the springing response of ships in waves.

  6. Creep in model pillars. [Salt, trona, and potash ore

    Energy Technology Data Exchange (ETDEWEB)

    Obert, L.

    1965-03-01

    A study was made of the deformational behavior (creep) of pillars made from three quasi-plastic rock--salt, trona, and potash ore. The first phase of this study considers the design of a model pillar suitable for creep tests; in the second phase, six model pillars were prepared from salt from two sources, from trona, and from potash ore. The pillars in each group were subjected to a different but constant axial stress, and the axial strain was measured for 1,000 hours. An analysis of the data shows that in general the creep rate for these model pillars can be expressed by the relationship .epsilon = K/sub 1/ sigma/sub 0//sup n/, where .epsilon is the strain rate, sigma/sub 0/ is the applied stress, and K/sub 1/ and n are constants. For the rocks included in this test, n ranged from 2.4 to 3.3.

  7. Genesis of ion-adsorption type REE ores in Thailand

    Science.gov (United States)

    Sanematsu, K.; Yoshiaki, K.; Watanabe, Y.

    2012-04-01

    Ion-adsorption type REE deposits, which have been economically mined only in southern China, are predominant supply sources for HREE in the world. The ore bodies consist of weathered granites called ion-adsorption ores. The majority of REE (>50 %) are electrostatically adsorbed onto weathering products in the ores and they can be extracted by ion exchange using an electrolyte solution (e.g., ammonium sulfate solution). Recently the occurrences of ion-adsorption ores have been reported in Indochina, SE Asia. In this study, we discuss geochemical and mineralogical characteristics of parent granites and weathered granites in Thailand in order to reveal the genesis of ion-adsorption ores. Permo-Triassic and Cretaceous-Paleogene granite plutons are distributed from northern Thailand to western Indonesia through eastern Myanmar and Peninsular Malaysia. They are mostly ilmenite-series calcalkaline biotite or hornblende-biotite granites. REE contents of the granites range from 60 to 600 ppm and they are relatively high in Peninsula Thailand. REE-bearing minerals consist mainly of apatite, zircon, allanite, titanite, monazite and xenotime. Some I-type granites contain REE fluorocarbonate (probably synchysite-(Ce)) in cavities and cracks in feldspars and it is the dominant source of REE for ion-adsorption ores because the fluorocarbonate is easily soluble during weathering. In contrast, insoluble monazite and xenotime are not preferable for ion-adsorption ores although they are common ore minerals of placer REE deposits. Weathered granites show REE contents ranging from 60 to 1100 ppm in Thailand because REE are relatively immobile compared with mobile elements (e.g., Na, K, Ca). In the weathered granites, REE are contained in residual minerals and secondary minerals and are adsorbed onto the surface of weathering products. A weathering profile of granite with ion-adsorption type mineralization can be divided into upper and lower parts based on REE enrichment and Ce

  8. Speciation and recovery of chromium from chromite ore processing residues.

    Science.gov (United States)

    Sreeram, K J; Ramasami, T

    2001-10-01

    The processing of chromite ore is associated with the generation of large quantities of solid wastes containing chromium, which have been disposed of as landfill for many years. The mobilization and operational speciation of chromium contained in soils contaminated with metal salts are important in terms of the environment. Several methods have been employed for the extraction and recovery of solid wastes. Chromium contained in contaminated soils and solid wastes can be categorized as exchangeable, oxidizable, carbonate-bound, reducible and residual. The results from this study indicate a need for efficient leaching methodologies in chromite ore processing plants to decrease the non-detrital fractions of chromium in the residue. Aggressive methodologies are required to recover chromium from the detrital fractions. The potential benefits of employing sodium peroxide for the complete recovery of chromium from chromite residue have been demonstrated, and the need to ensure the safety of the process has been emphasized.

  9. Method of winning aluminum metal from aluminous ore

    Science.gov (United States)

    Loutfy, Raouf O.; Keller, Rudolf; Yao, Neng-Ping

    1981-01-01

    Aluminous ore such as bauxite containing alumina is blended with coke or other suitable form of carbon and reacted with sulfur gas at an elevated temperature. For handling, the ore and coke can be extruded into conveniently sized pellets. The reaction with sulfur gas produces molten aluminum sulfide which is separated from residual solid reactants and impurities. The aluminum sulfide is further increased in temperature to cause its decomposition or sublimation, yielding aluminum subsulfide liquid (AlS) and sulfur gas that is recycled. The aluminum monosulfide is then cooled to below its disproportionation temperature to again form molten aluminum sulfide and aluminum metal. A liquid-liquid or liquid-solid separation, depending on the separation temperature, provides product aluminum and aluminum sulfide for recycle to the disproportionation step.

  10. Direct reduction of iron ore by biomass char

    Science.gov (United States)

    Zuo, Hai-bin; Hu, Zheng-wen; Zhang, Jian-liang; Li, Jing; Liu, Zheng-jian

    2013-06-01

    By using thermogravimetric analysis the process and mechanism of iron ore reduced by biomass char were investigated and compared with those reduced by coal and coke. It is found that biomass char has a higher reactivity. The increase of carbon-to-oxygen mole ratio (C/O) can lead to the enhancement of reaction rate and reduction fraction, but cannot change the temperature and trend of each reaction. The reaction temperature of hematite reduced by biomass char is at least 100 K lower than that reduced by coal and coke, the maximum reaction rate is 1.57 times as high as that of coal, and the final reaction fraction is much higher. Model calculation indicates that the use of burden composed of biomass char and iron ore for blast furnaces can probably decrease the temperature of the thermal reserve zone and reduce the CO equilibrium concentration.

  11. Cadmium extraction from phosphate ore. Effect of microwave

    Directory of Open Access Journals (Sweden)

    Zahia Benredjem

    2016-09-01

    Full Text Available This study discusses the operating variables for removal of cadmium from phosphate ore using Na2EDTA. These variables include the reaction time, Na2EDTA concentration, liquid/phosphate ore ratio, number of extractions and microwave extraction. Na2EDTA induced a two-step extraction process including a rapid extraction within the first hour, and a subsequent gradual release that occurred over the following hours. The cadmium extraction efficiency increased progressively with the increasing of Na2EDTA concentration. The extraction efficiency of cadmium increased with increasing liquid/phosphate ratio in the 5–200 range. Consecutive extractions using low concentrations were more effective than a single soil extraction with concentrated Na2EDTA. Microwave was beneficial to improve the removal in soil washing, and using microwave could partly substitute for agitation.

  12. Estimation of springing response for 550 000 DWT ore carrier

    Science.gov (United States)

    Adenya, Christiaan Adika; Ren, Huilong; Li, Hui; Wang, Di

    2016-09-01

    The desire to benefit from economy of scale is one of the major driving forces behind the continuous growth in ship sizes. However, models of new large ships need to be thoroughly investigated to determine the carrier's response in waves. In this work, experimental and numerical assessments of the motion and load response of a 550,000 DWT ore carrier are performed using prototype ships with softer stiffness, and towing tank tests are conducted using a segmented model with two schemes of softer stiffness. Numerical analyses are performed employing both rigid body and linear hydroelasticity theories using an in-house program and a comparison is then made between experimental and numerical results to establish the influence of stiffness on the ore carrier's springing response. Results show that softer stiffness models can be used when studying the springing response of ships in waves.

  13. Bacterial leaching of discarded copper ores from Yongping, China

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The elementary and phase analysis of discarded copper ores from Yongping of China has been performed. The experiments of extracting copper from the discarded copper ores were done with the mixed bacteria obtained through a series of enrichment,separation, domestication and combination tests. The results show that in the process of bioleaching, the pH value rises at first and drops gradually. The Eh value keeps rising along with the time and the appropriate Eh value varying between 750 and 800 mV will benefit the bioleaching copper. The high concentration of ferric ions is detrimental to the bioleaching copper. The results of bioleaching copper are good. That is, the copper recovery is 31.8% after 27 days.

  14. Flotation studies on low grade graphite ore from eastern India

    Institute of Scientific and Technical Information of China (English)

    Vasumathi N.; Vijaya Kumar T.V.; Ratchambigai S.; Subba Rao S.; Bhaskar Raju G

    2015-01-01

    A low grade graphite ore from eastern India was beneficiated by flotation to improve its quality. The ore was composed of 87.80%ash and 8.59%fixed carbon. Primary coarse wet grinding (d80:186 lm) followed by rougher flotation in Denver flotation cell using diesel as collector and pine oil as frother yielded a rougher concentrate. Regrinding (d80:144 lm) of this rougher concentrate was opted for further libera-tion of graphite. It was followed by cleaning in laboratory flotation column. This combined process of relatively coarse primary grinding followed by regrinding and cleaning in flotation column resulted in final concentrate of 7.44% yield with 89.65% fixed carbon and 6.00% ash. This approach of two-stage grinding to recover the flake graphite at the coarsest possible grind can help to minimize grinding energy costs. A conceptual flow sheet which is cost effective was developed based on this methodology.

  15. Ore mineralogy of the Serra Pelada Au-Pd-Pt deposit, Carajás, Brazil and implications for ore-forming processes

    Science.gov (United States)

    Berni, Gabriel V.; Heinrich, Christoph A.; Lobato, Lydia M.; Wall, Vic

    2016-08-01

    Serra Pelada is a world-class hydrothermal Au-Pd-Pt deposit located at the eastern border of the Amazon craton, northern Brazil. The rocks at Serra Pelada have experienced intense tropical weathering for about 70 Ma, but drill core samples preserve the primary mineralogy and hydrothermal alteration features, with extreme grades of Au, Pd and Pt individually reaching hundreds of parts per million (ppm) by weight. Mineralization at Serra Pelada occurs in hydrothermally altered metasiltstones and dolomitic metasandstones at the hinge zone of a recumbent syncline, comprising zones of hematite, chlorite-carbon, argillic, and siliceous alteration. The main hydrothermal gangue minerals are quartz, kaolinite, sericite, amesite, hematite, monazite, florencite and variable amounts of highly reflective carbonaceous matter. Hydrothermal carbon input is evident from precipitated carbon occurring along crenulation planes and veinlets associated with the precious metals. Ore and accessory minerals include a variety of sulphide, selenide, arsenide, sulphate and oxide minerals, including gold with variable metal contents, palladian gold, fischesserite, sudovikovite, sperrylite, selenian braggite, isomertieite, mertieite-II and secondary Au-Pt-Pd alloys. The composition of fischesserite varies from the ideal formula (Ag3AuSe2) towards a more Ag-rich composition, indicating a disordered solid solution form that is stable only above 260 °C, consistent with the high thermal maturity of associated carbonaceous matter approaching graphite. Primary ore and gangue minerals at Serra Pelada comprise a suite of elements that are best transported in oxidising conditions and precipitated upon reduction. This suggests that fluid mixing between a highly oxidised (metal carrier) and a reduced fluid was a key process for high-grade noble metal precipitation at Serra Pelada.

  16. Petrography and geochemistry of the primary ore zone of the Kenticha rare metal granite-pegmatite field, Adola Belt, Southern Ethiopia: Implications for ore genesis and tectonic setting

    Science.gov (United States)

    Mohammedyasin, Mohammed Seid; Desta, Zerihun; Getaneh, Worash

    2017-10-01

    The aim of this work is to evaluate the genesis and tectonic setting of the Kenticha rare metal granite-pegmatite deposit using petrography and whole-rock geochemical analysis. The samples were analysed for major elements, and trace and rare earth elements by ICP-AES and ICP-MS, respectively. The Kenticha rare metal granite-pegmatite deposit is controlled by the N-S deep-seated normal fault that allow the emplacement of the granite-pegmatite in the study area. Six main mineral assemblages have been identified: (a) alaskitic granite (quartz + microcline + albite with subordinate muscovite), (b) aplitic layer (quartz + albite), (c) muscovite-quartz-microcline-albite pegmatite, (d) spodumene-microcline-albite pegmatite, partly albitized or greisenized, (e) microcline-albite-green and pink spodumene pegmatite with quartz-microcline block, which is partly albitized and greisenized, and (f) quartz core. This mineralogical zonation is also accompanied by variation in Ta ore concentration and trace and rare earth elements content. The Kenticha granite-pegmatite is strongly differentiated with high SiO2 (72-84 wt %) and enriched with Rb (∼689 ppm), Be (∼196 ppm), Nb (∼129 ppm), Ta (∼92 ppm) and Cs (∼150 ppm) and depleted in Ba and Sr. The rare earth element (REE) patterns of the primary ore zone (below 60 m depth) shows moderate enrichment in light REE ((La/Yb)N = ∼8, and LREE/HREE = ∼9.96) and negative Eu-anomaly (Eu/Eu* = ∼0.4). The whole-rock geochemical data display the Within Plate Granite (WPG) and syn-Collisional Granite (syn-COLG) suites and interpret as its formation is crustal related melting. The mineralogical assemblage, tectonic setting and geochemical signatures implies that the Kenticha rare metal bearing granite pegmatite is formed by partial melting of metasedimentary rocks during post-Gondwana assembly and further tantalite enrichment through later hydrothermal-metasomatic processes.

  17. PHASE ANALYSES OF URANIUM-BEARING MINERALS FROM THE HIGH GRADE ORE, NOPAL I, PENA BLANCA, MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    M. Ren; P. Goodell; A. Kelts; E.Y. Anthony; M. Fayek; C. Fan; C. Beshears

    2005-07-11

    The Nopal I uranium deposit is located in the Pena Blanca district, approximately 40 miles north of Chihuahua City, Mexico. The deposit was formed by hydrothermal processes within the fracture zone of welded silicic volcanic tuff. The ages of volcanic formations are between 35 to 44 m.y. and there was secondary silicification of most of the formations. After the formation of at least part of the uranium deposit, the ore body was uplifted above the water table and is presently exposed at the surface. Detailed petrographic characterization, electron microprobe backscatter electron (BSE) imagery, and selected x-ray maps for the samples from Nopal I high-grade ore document different uranium phases in the ore. There are at least two stages of uranium precipitation. A small amount of uraninite is encapsulated in silica. Hexavalent uranium may also have been a primary precipitant. The uranium phases were precipitated along cleavages of feldspars, and along fractures in the tuff. Energy dispersive spectrometer data and x-ray maps suggest that the major uranium phases are uranophane and weeksite. Substitutions of Ca and K occur in both phases, implying that conditions were variable during the mineralization/alteration process, and that compositions of the original minerals have a major influence on later stage alteration. Continued study is needed to fully characterize uranium behavior in these semi-arid to arid conditions.

  18. Comprehensive recovery of gold and base-metal sulfide minerals from a low-grade refractory ore

    Institute of Scientific and Technical Information of China (English)

    Wen-juan Li; Shuang Liu; Yong-sheng Song; Jian-kang Wen; Gui-ying Zhou; and Yong Chen

    2016-01-01

    The comprehensive recovery of small amounts of valuable minerals such as gold and base-metal sulfide minerals from a low-grade refractory ore was investigated. The following treatment strategy was applied to a sample of this ore: gold flotation–gold concen-trate leaching–lead and zinc flotation from the gold concentrate leaching residue. Closed-circuit trials of gold flotation yielded a gold concen-trate that assayed at 40.23 g·t−1Au with a recovery of 86.25%. The gold concentrate leaching rate was 98.76%. Two variants of lead-zinc flotation from the residue—preferential flotation of lead and zinc and bulk flotation of lead and zinc—were tested using the middling proc-essing method. Foam from the reflotation was returned to the lead rougher flotation or lead–zinc bulk flotation, whereas middlings from re-flotation were discarded. Sulfur concentrate was a byproduct. The combined strategy of flotation, leaching, and flotation is recommended for the treatment of this kind of ore.

  19. Comprehensive recovery of gold and base-metal sulfide minerals from a low-grade refractory ore

    Science.gov (United States)

    Li, Wen-juan; Liu, Shuang; Song, Yong-sheng; Wen, Jian-kang; Zhou, Gui-ying; Chen, Yong

    2016-12-01

    The comprehensive recovery of small amounts of valuable minerals such as gold and base-metal sulfide minerals from a low-grade refractory ore was investigated. The following treatment strategy was applied to a sample of this ore: gold flotation-gold concentrate leaching-lead and zinc flotation from the gold concentrate leaching residue. Closed-circuit trials of gold flotation yielded a gold concentrate that assayed at 40.23 g·t-1 Au with a recovery of 86.25%. The gold concentrate leaching rate was 98.76%. Two variants of lead-zinc flotation from the residue—preferential flotation of lead and zinc and bulk flotation of lead and zinc—were tested using the middling processing method. Foam from the reflotation was returned to the lead rougher flotation or lead-zinc bulk flotation, whereas middlings from reflotation were discarded. Sulfur concentrate was a byproduct. The combined strategy of flotation, leaching, and flotation is recommended for the treatment of this kind of ore.

  20. Natural radionuclide concentrations in two phosphate ores of east Algeria

    Energy Technology Data Exchange (ETDEWEB)

    Lakehal, Ch. [Department of Physics, Mentouri Constantine University, 25000 Constantine (Algeria); Ramdhane, M., E-mail: ramdhane@hotmail.co [Department of Physics, Mentouri Constantine University, 25000 Constantine (Algeria); Boucenna, A. [Department of Physics, Ferhat-Abbas University, 19000 Setif (Algeria)

    2010-05-15

    Ore is considered as an important source of many elements such as the iron, phosphorus, and uranium. Concerning the natural radionuclides, their concentrations vary from an ore to other depending on the chemical composition of each site. In this work, two phosphate ores found in East of Algeria have been chosen to assess the activity concentration of natural radionuclides represented mainly by three natural radioactive series {sup 238}U, {sup 235}U and {sup 232}Th, and the primordial radionuclide {sup 40}K where they were determined using ultra-low background, high-resolution gamma-ray spectroscopy. The measured activity concentrations of radioactive series ranged from 6.2 +- 0.4 to 733 +- 33 Bq.kg{sup -1} for the {sup 232}Th series, from 249 +- 16 to 547 +- 39 Bq.kg{sup -1} for the {sup 238}U series, around 24.2 +- 2.5 Bq.kg{sup -1} for the {sup 235}U series, and from 1.4 +- 0.2 to 6.7 +- 0.7 Bq.kg{sup -1} for {sup 40}K. To assess exposure to gamma radiation in the two ores, from specific activities of {sup 232}Th, {sup 40}K and {sup 226}Ra, three indexes were determined: Radium equivalent (Ra{sub eq}), external and internal hazard indexes (H{sub ex} and H{sub in}), their values ranged from 831 +- 8 to 1298 +- 14 Bq.kg{sup -1} for Ra{sub eq}, from 2.2 +- 0.4 to 3.5 +- 0.7 Bq.kg{sup -1} for H{sub ex}, and from 4.2 +- 0.7 to 4.5 +- 0.7 Bq.kg{sup -1} for H{sub in}.

  1. The extractive metallurgy of south africa's platinum ores

    Science.gov (United States)

    Cramer, Larry A.

    2001-10-01

    The extraction technology for platinum-group metals (PGMs) has changed dramatically in the last 80 years, and the changes are likely to continue for years to come. This article will review advances in PGM extraction, including developments in semi-autogenous and fully autogenous milling; flotation equipment applications for treating high-chrome ores; increases in power densities for future smelting furnaces, and new methods for meeting rising environmental standards.

  2. PROCESS FOR THE RECOVERY OF URANIUM FROM PHOSPHATIC ORE

    Science.gov (United States)

    Long, R.L.

    1959-04-14

    A proccss is described for the recovery of uranium from phosphatic products derived from phosphatic ores. It has been discovered that certain alkyl phosphatic, derivatives can be employed in a direct solvent extraction operation to recover uranium from solid products, such as superphosphates, without first dissolving such solids. The organic extractants found suitable include alkyl derivatives of phosphoric, pyrophosphoric, phosof the derivative contains from 4 to 7 carbon atoms. A diluent such as kerosene is also used.

  3. Bioprocessing low grade copper ores - a promising alternative

    OpenAIRE

    Guezennec, Anne-Gwenaëlle; d'Hugues, Patrick

    2015-01-01

    International audience; This paper presents an overview of the work performed by the BRGM team in the last 10 years on the development of bio-hydrometallurgy dedicated to the processing of low-grade copper ores from the Kupferschiefer deposits. It covers selection and adaptation of microbial consortia, optimization of process operating parameters such as solid contents, the relationship between bioleaching performance and mineralogy, testing operating parameters to overcome chalcopyrite recal...

  4. Potential ecological and human health risks of heavy metals in surface soils associated with iron ore mining in Pahang, Malaysia.

    Science.gov (United States)

    Diami, Siti Merryan; Kusin, Faradiella Mohd; Madzin, Zafira

    2016-10-01

    The composition of heavy metals (and metalloid) in surface soils of iron ore mine-impacted areas has been evaluated of their potential ecological and human health risks. The mining areas included seven selected locations in the vicinity of active and abandoned iron ore-mining sites in Pahang, Malaysia. Heavy metals such as Fe, Mn, Cu, Zn, Co, Pb, Cr, Ni, and Cd and metalloid As were present in the mining soils of the studied area, while Cu was found exceeding the soil guideline value at all sampling locations. However, the assessment of the potential ecological risk index (RI) indicated low ecological risk (RI between 44 and 128) with respect to Cd, Pb, Cu, As, Zn, Co, and Ni in the surface soils. Contributions of potential ecological risk [Formula: see text]by metal elements to the total potential ecological RI were evident for Cd, As, Pb, and Cu. Contribution of Cu appears to be consistently greater in the abandoned mining area compared to active iron ore-mining site. For non-carcinogenic risk, no significant potential health risk was found to both children and adults as the hazard indices (HIs) were all below than 1. The lifetime cancer risk (LCR) indicated that As has greater potential carcinogenic risk compared to other metals that may induce carcinogenic effects such as Pb, Cr, and Cd, while the LCR of As for children fell within tolerable range for regulatory purposes. Irrespective of carcinogenic or non-carcinogenic risk, greater potential health risk was found among children (by an order of magnitude higher for most metals) compared to adults. The hazard quotient (HQ) and cancer risk indicated that the pathways for the risk to occur were found to be in the order of ingestion > dermal > inhalation. Overall, findings showed that some metals and metalloid were still present at comparable concentrations even long after cessation of the iron ore-mining activities.

  5. Impact of microbial communities from tropical soils on the mobilization of trace metals during dissolution of cinnabar ore.

    Science.gov (United States)

    Balland-Bolou-Bi, Clarisse; Turc, Benjamin; Alphonse, Vanessa; Bousserrhine, Noureddine

    2017-06-01

    Biodissolution experiments on cinnabar ore (mercury sulphide and other sulphide minerals, such as pyrite) were performed with microorganisms extracted directly from soil. These experiments were carried out in closed systems under aerobic and anaerobic conditions with 2 different soils sampled in French Guyana. The two main objectives of this study were (1) to quantify the ability of microorganisms to mobilize metals (Fe, Al, Hg) during the dissolution of cinnabar ore, and (2) to identify the links between the type and chemical properties of soils, environmental parameters such as season and the strategies developed by indigenous microorganisms extracted from tropical natural soils to mobilize metals. Results indicate that microbial communities extracted directly from various soils are able to (1) survive in the presence of cinnabar ore, as indicated by consumption of carbon sources and, (2) leach Hg from cinnabar in oxic and anoxic dissolution experiments via the acidification of the medium and the production of low molecular mass organic acids (LMMOAs). The dissolution rate of cinnabar in aerobic conditions with microbial communities ranged from 4.8×10(-4) to 2.6×10(-3)μmol/m(2)/day and was independent of the metabolites released by the microorganisms. In addition, these results suggest an indirect action by the microorganisms in the cinnabar dissolution. Additionally, because iron is a key element in the dynamics of Hg, microbes were stimulated by the presence of this metal, and microbes released LMMOAs that leached iron from iron-bearing minerals, such as pyrite and oxy-hydroxide of iron, in the mixed cinnabar ore. Copyright © 2016. Published by Elsevier B.V.

  6. Geochemistry and S, Pb isotope of the Yangla copper deposit, western Yunnan, China: Implication for ore genesis

    Science.gov (United States)

    Yang, Xi-An; Liu, Jia-Jun; Cao, Ye; Han, Si-Yu; Gao, Bing-yu; Wang, Huan; Liu, Yue-Dong

    2012-07-01

    The Yangla copper deposit, situated in the middle section of Jinshajiang tectonic belt between Zhongza-Zhongdian block and Changdu-Simao block, is a representative and giant copper deposit that has been discovered in Jinshajiang-Lancangjiang-Nujiang region in recent years. There are coupled relationships between Yangla granodiorite and copper mineralization in the Yangla copper deposit. Five molybdenite samples yielded a well-constrained 187Re-187Os isochron age of 233.3 ± 3 Ma, the metallogenesis is therefore slightly younger than the crystallization age of the granodiorite. S, Pb isotopic compositions of the Yangla copper deposit indicate that the ore-forming materials were derived from the mixture of upper crust and mantle, also with the magmatic contributions. In the late Early Permian, the Jinshajiang Oceanic plate was subducted to the west, resulting in the formation of a series of gently dipping thrust faults in the Jinshajiang tectonic belt, meanwhile, accompanied magmatic activities. In the early Late Triassic, which was a time of transition from collision-related compression to extension in the Jinshajiang tectonic belt, the thrust faults were tensional; it would have been a favorable environment for forming ore fluids. The ascending magma provided a channel for the ore-forming fluid from the mantle wedge. After the magma arrived at the base of the early-stage Yangla granodiorite, the platy granodiorite at the base of the body would have shielded the late-stage magma from the fluid. The magma would have cooled slowly, and some of the ore-forming fluid in the magma would have entered the gently dipping thrust faults near the Yangla granodiorite, resulting in mineralization.

  7. Atmospheric emission of polychlorinated naphthalenes from iron ore sintering processes.

    Science.gov (United States)

    Liu, Guorui; Zheng, Minghui; Du, Bing; Nie, Zhiqiang; Zhang, Bing; Liu, Wenbin; Li, Cheng; Hu, Jicheng

    2012-10-01

    Iron ore sintering processes constitute significant sources of dioxins, and studies have confirmed a close correlation between polychlorinated naphthalenes (PCNs) and dioxin formation. Thus, iron ore sintering processes are thought to be a potential source of PCNs, although intensive investigations on PCN emissions from sintering processes have not been carried out. Therefore, the aim of the present study was to qualify and quantify PCN emissions from nine sintering plants operating on different industrial scales. PCN concentrations ranged from 3 to 983 ng m(-3) (0.4-23.3 pg TEQ(PCN) m(-3)) and emission factors ranged from 14 to 1749 μg t(-1) (0.5-41.5 ng TEQ(PCN) t(-1)), with a geometric mean of 84 μg t(-1) (2.1 ng TEQ(PCN) t(-1)). The estimated annual emission of PCNs from sintering processes in China was 1390 mg TEQ(PCN). These figures will assist in the development of a PCN emissions inventory. Regarding emission characteristics, PCNs mainly comprised low-chlorinated homologs. The ratios of several characteristic PCN congeners were also measured and compared with those from other sources. Taken together, these results may provide useful information for identifying the sources of PCNs produced by iron ore sintering processes. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. On the problems of the Litija ore field

    Directory of Open Access Journals (Sweden)

    Ivan Mlakar

    1994-12-01

    Full Text Available All available information on the now inaccessible Pb-Zb-Ba deposits Litija, Zavrstnik, Zagorica, Maljek, Hrastarija and Štriglovec was critically evaluated. Data were completed and numerous earlier unsolved questions were answered.In the studied area the existence of a Middle Triassic tectonic-erosional phase was proved, the Old Tertiary overthrust structure analyzed and the relative ages of various neotectonic fault systems established.Special attention was attributed to the Litija, or Sitarjevec, deposit. On the ground of data on position of thick shale intercalations within Carboniferous sandstone the geological structure of the deposit was reconstructed, proofs on the conforming or unconforming position of orebodies collected, and certain relati¬onships between the pre-ore and post-ore tectonics clarified. With geochemical investigations the presence of an extensive dispersion halo was proved, in which the anomalies produced by Pb, Hg and Ba are the best expressed.Also the position of other deposits in space and in stratigraphic column was defined. At the end also the author's views on genesis and age of mineralization are presented. Orebodies are hydrothermal. subvertical, epignetic and predominantly discordant, with poorly expressed vertical zoning.The work is a synthesis of understanding of geological structure and mineralization in the Litija ore field.

  9. Contact mechanical analysis of O-ring stresses

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung Kyu

    2007-02-15

    The purpose of this project is to develop the approximate solutions of contact traction and internal stress of an O-ring by using a two dimensional elasticity for enhancing the design and failure prediction technology. Investigated were the applicability of Lindley's formulae of contact force prediction and the Hertz theory. Three cases of O-ring installation were considered. The approximate solution of contact tractions and internal stresses of each case were derived. The key results are summarized as follows: 1. It is verified that Lindley's formulae predicts the relationship between the fractional compression and contact force. 2. In the case of Case I, II and III without internal pressure, it is found that a function form of the contact traction is the Hertzian. So it is possible to express the traction with a Hertzian form and correction factors. 3. The internal stresses are derived in the case of the Hertzian traction profile. The stresses at the center of O-ring show a satisfactory result when compared with the finite element result.

  10. Treatment of coking wastewater by using manganese and magnesium ores

    Energy Technology Data Exchange (ETDEWEB)

    Chen Tianhu; Huang Xiaoming; Pan Min [School of Resources and Environmental Engineering, Hefei University of Technology, Hefei City 230009 (China); Jin Song, E-mail: sjin@uwyo.edu [MWH Americas, 3665 JFK Parkway, Suite 206, Fort Collins, CO 80525 (United States); Department Civil and Architectural Engineering, University of Wyoming, Laramie, WY 82071 (United States); Peng Suchuan [School of Resources and Environmental Engineering, Hefei University of Technology, Hefei City 230009 (China); Fallgren, Paul H. [Western Research Institute, 365 North 9th Street, Laramie, WY 82072 (United States)

    2009-09-15

    This study investigated a wastewater treatment technique based on natural minerals. A two-step process using manganese (Mn) and magnesium (Mg) containing ores were tested to remove typical contaminants from coking wastewater. Under acidic conditions, a reactor packed with Mn ore demonstrated strong oxidizing capability and destroyed volatile phenols, chemical oxygen demand (COD){sub ,} and sulfide from the coking wastewater. The effluent was further treated by using Mg ore to remove ammonium-nitrogen and phosphate in the form of magnesium ammonium phosphate (struvite) precipitates. When pH of the wastewater was adjusted to 1.2, the removal efficiencies for COD, volatile phenol and sulfide reached 70%, 99% and 100%, respectively. During the second step of precipitation, up to 94% of ammonium was removed from the aqueous phase, and precipitated in the form of struvite with phosphorus. The struvite crystals showed a needle-like structure. X-ray diffraction and transmission electron microscopy were used to characterize the crystallized products.

  11. Source of ore-forming substances and theoretical problems of metallogeny relevant to the Bayan Obo Fe-REE ore deposits in Inner Mongolia,China

    Institute of Scientific and Technical Information of China (English)

    曹荣龙; 朱寿华; 王俊文

    1995-01-01

    The source of rare earth elements (REE) ore-forming substances is identified to be extremelydistinct from that of iron ores.The Bayan Obo Fe-REE ore deposits were generated by a composite processof both crustal and mantle source mineralization.The original iron bodies are of a sedimentary deposit fromsupergenesis,while the REE ores have been formed by mantle fluid metasomatism superimposed upon thepre-existing iron bodies.It is believed that the REE ore deposit would be controlled by intracontinental hotspot.The H8 dolomite in mine regions belongs to normal sedimentary carbonate rock,its C and O isotopiccomposition rules out the possibility comparable with magrnatic carbonatite.The Sm-Nd isochrons of separatedREE minerals have shown two REE peak mineralization periods:early-middle Proterozoic (1 700 Ma±480 Ma) andCaledonia (424-402 Ma).

  12. Anisotropy of magnetic susceptibility in the giant Lac Tio hemo-ilmenite ore body (Quebec Province, Canada): source and geological implications

    Science.gov (United States)

    Bolle, O.; Diot, H.; Bascou, J.; Charlier, B.

    2012-04-01

    The Lac Tio hemo-ilmenite ore body is a magmatic ilmenite deposit that crops out in the 1.06 Ga Lac Allard anorthosite which is part of the Havre-Saint-Pierre anorthosite suite, one of many AMCG (Anorthosite-Mangerite-Charnockite-(rapakivi) Granite) suites from the Grenville province of North America. It is the world's largest hard-rock ilmenite deposit, with reserves still estimated at ca. 138 Mt after 60 years of mining exploitation (Charlier et al., 2010). The magnetic properties of the Lac Tio ore body were first studied in the 50s and 60s (e.g. Hargraves, 1959; Carmichael, 1961), and have recently been reinvestigated by McEnroe et al. (2007). All these works focused on the high and stable natural remanent magnetization of the hemo-ilmenite ore (up to 120 A/m) that was shown to reside in the exsolution intergrowths of hematite and ilmenite, following the theory of lamellar magnetism (McEnroe et al., 2007). The present study investigates the anisotropy of magnetic susceptibility (AMS; e.g. Borradaile and Jackson, 2004) of 46 samples from the Lac Tio ore body and its anorthosite wall rocks. The bulk magnetic susceptibility (Km) in the ore, which is essentially made up of hemo-ilmenite (commonly >75 wt.%) and plagioclase, ranges from 5.3 to 115.9 x 10-3 SI. Not surprisingly, samples with high Km values (>7 x 10-3 SI) usually contain magnetite, either as small grains or as plates replacing some hematite exsolutions. Km ranges from 0.35 to 3.8 x 10-3 SI in the host anorthosite, as well as in plagicolase-rich layers found within the hemo-ilmenite ore. Such relatively low values reflect minor to trace amounts of Fe-Ti oxides (ilmeno-hematite, hemo-ilmenite, magnetite) and pyroxenes. The hemo-ilmenite ore displays a shape-preferred orientation of the hematite lamellae that exsolved parallel to the basal (0001) plane of the ilmenite host grains. Thus, the ore has a lattice-preferred orientation (LPO) for the hemo-ilmenite grains. Electron backscatter diffraction

  13. Quantitative mineralogical characterization of chrome ore beneficiation plant tailing and its beneficiated products

    Science.gov (United States)

    Das, S. K.

    2015-04-01

    Mineralogical characterization and liberation of valuable minerals are primary concerns in mineral processing industries. The present investigation focuses on quantitative mineralogy, elemental deportment, and locking-liberation characteristics of the beneficiation of tailings from a chrome ore beneficiation plant in the Sukinda region, Odisha; methods used for the study of the beneficiated tailings are QEMSCAN®, X-ray diffraction (XRD), and mineral chemistry by a scanning electron microscope equipped with an energy-dispersive spectrometer (SEM-EDS). The tailing sample was fine grained (69.48wt% below 45 μm size), containing 20.25wt% Cr2O3 and 39.19wt% Fe2O3, with a Cr:Fe mass ratio of 0.51. Mineralogical investigations using QEMSCAN studies revealed that chromite, goethite, and gibbsite are the dominant mineral phases with minor amounts of hematite, kaolinite, and quartz. The sample contained 34.22wt% chromite, and chromite liberation is more than 80% for grains smaller than 250 μm in size. Based on these results, it was predicted that liberated chromite and high-grade middling chromite particles could be separated from the gangue by various concentration techniques. The tailing sample was beneficiated by hydrocyclone, tabling, wet high-intensity magnetic separation (WHIMS), and flotation in order to recover the chromite. A chromite concentrate with 45.29wt% Cr2O3 and a Cr:Fe mass ratio of 1.85 can be produced from these low-grade chromite ore beneficiation plant rejects.

  14. Kinetics of thermal decomposition of hydrated minerals associated with hematite ore in a fluidized bed reactor

    Science.gov (United States)

    Beuria, P. C.; Biswal, S. K.; Mishra, B. K.; Roy, G. G.

    2017-03-01

    The kinetics of removal of loss on ignition (LOI) by thermal decomposition of hydrated minerals present in natural iron ores (i.e., kaolinite, gibbsite, and goethite) was investigated in a laboratory-scale vertical fluidized bed reactor (FBR) using isothermal methods of kinetic analysis. Experiments in the FBR in batch processes were carried out at different temperatures (300 to 1200°C) and residence time (1 to 30 min) for four different iron ore samples with various LOIs (2.34wt% to 9.83wt%). The operating velocity was maintained in the range from 1.2 to 1.4 times the minimum fluidization velocity ( U mf). We observed that, below a certain critical temperature, the FBR did not effectively reduce the LOI to a desired level even with increased residence time. The results of this study indicate that the LOI level could be reduced by 90% within 1 min of residence time at 1100°C. The kinetics for low-LOI samples (reaction mechanisms in two temperature regimes. At lower temperatures (300 to 700°C), the kinetics is characterized by a lower activation energy (diffusion-controlled physical moisture removal), followed by a higher activation energy (chemically controlled removal of LOI). In the case of high-LOI samples, three different kinetics mechanisms prevail at different temperature regimes. At temperature up to 450°C, diffusion kinetics prevails (removal of physical moisture); at temperature from 450 to 650°C, chemical kinetics dominates during removal of matrix moisture. At temperatures greater than 650°C, nucleation and growth begins to influence the rate of removal of LOI.

  15. From BIF to Iron Ore - A journey from nanocrystals to huge iron ore deposits of the Hamersley Province, Australia

    OpenAIRE

    Egglseder, Mathias

    2017-01-01

    Banded iron formations (BIFs) are extraordinary rocks because they provide important information about the Precambrian atmosphere and hydrosphere, the global rise of oxygen, and they host the world’s major iron ore deposits. The unique texture and petrology of BIF, which mainly comprise alternating layers of iron oxides and chert remain poorly understood. Although the mineral assemblage is of diagenetic or metamorphic origin, BIF textures are interpreted as sedimentary st...

  16. Leaching of Silver from Boorchi Ag-Pb Ore in Mongolia with Acidic Thiourea Solution

    Institute of Scientific and Technical Information of China (English)

    Nyamdelger Shirchinnamjil; 杨超; 方兆珩

    2008-01-01

    A hydrometalhirgical process to extract silver from the silver-lead ore in Boorchi, Mongolia by using thiourealeaching solution is studied in this work. Through the observation of optical and scanning electron microscopes, and energyspectral analysis, it is determined that 5 kinds of silver minerals exist in the ore, including argentite, Ag-tetrahedrite,Ag-Zn-Sb-tetrahedrite, freibergite and acanthite. The experimental results of direct thiourea leaching of the ore show that56%~60% of silver is leached. The main reason for the low leaching rate is due to silver minerals enveloped in galena andother minerals, even though the ore is ground to the particle size of 75 μm. When the ore is pretreated with ammoniumcarbonate solution under oxidation, the experimental results of thiourea leaching show that the leaching rate of silver increasesto near 75% with the pretreatment. Based on the leaching experiments, a principle hydrometallurgical technological route toextract silver from the Ag-Pb ore is proposed.

  17. Geology and ore deposits of the Pioche district, Nevada

    Science.gov (United States)

    Westgate, L.G.; Knopf, Adolph

    1932-01-01

    LOCATION AND SURFACE FEATURES The Bristol Range, Highland, and Ely Range quadrangles make up the larger part of a. rectangular area 35 miles north and south by 24 miles east and west, which lies 19 miles west of the Nevada-Utah line and about 250 miles southwest of Salt Lake City. The district lies within the Great Basin, a semiarid region of alternating mountain ranges and intermontane plains floored largely by outwash from the mountains. The plain, which slopes away from the ranges, stands between 4,700 and 6,000 feet above the sea. The Bristol and Highland Ranges, which are separated only by a low gap, form an almost continuous north-south range that rises about 2,500 feet above the highest part of the surrounding plain, to general altitudes of 8,000 to 9,000 feet, though the highest point, Highland Peak, reaches 9,395 feet. A lower range, the Ely Range, with a northwesterly trend, lies farther east and nearly in touch with the Bristol-Highland Range. The town of Pioche lies midway on the. eastern foot of the Ely Range. ROOKS OF THE PIOOHB REGION The rocks of the ranges are Paleozoic sediments, Tertiary (?) lavas and intrusive rocks, and Pliocene (?) tuffs. The Paleozoic sediments have a total thickness of nearly 18,000 feet. Over 8,000 feet of the Cambrian has been measured without reaching its base. The lowest Cambrian formation is a quartzite, of which only the upper 1,500 feet is exposed, and this is followed by 1,200 feet of shale, 400 feet of limestone, aoid 150 feet of shale. Above this second shale the upper three-fourths of the Cambrian consists of limestone and dolomitic limestone. It is in the quartzite and in the limestone interbedded in and bounding the shales that the main ore bodies of the district have been found. Above the Cambrian comes 1,795 feet of Ordovician limestone, with some interbedded dolomite and with a 50-foot quartzite a, third of the way down from the top; 75 feet of Silurian dolomite; 3,000 feet of Middle Devonian dolomite with

  18. Effects of iron oxidizing bacteria in thiourea leaching of gold ores

    OpenAIRE

    甲斐, 敬美; 山崎, 研市; 高橋, 武重; カイ, タカミ; ヤマサキ, ケンイチ; タカハシ, タケシゲ; KAI, Takami; YAMASAKI, Kenichi; Takahashi, Takeshige

    1991-01-01

    Bacterial leaching was combined with thiourea method for the gold leaching from ores. For gold bearing pyrites, biological pre-oxidation has been generally perfomed. In the present study, we carried out the biological treatment to the high silicate bearing ores by using the iron oxidizing bacteria, Thiobacillus ferrooxidans. The recovery of gold and silver was enhanced by the biological pretreatment, while the effects of the treatment was influenced by the types of gold ores. Since the biolog...

  19. Analysis of Characteristics of Ore about Iron Deposit of Da Hong Mountain in Yun Nan Province

    Directory of Open Access Journals (Sweden)

    Zhang Yuefeng

    2016-01-01

    Full Text Available This thesis aims to analyse the deposit characteristics about Da Hong Mountains Iron ore in Yunnan province. The texture and structure, especially the chemical composition, is different in every section of deposit after comparing. Moreover, the content of SiO2 is much higher than general iron ore. However, the content of other noble metals cannot reach the lowest industrial grade. Da Hong Mountains Iron ore has unique features because of metallogenic periods.

  20. Chemical composition analysis of raw materials used in iron ore sinter plants in Poland

    Directory of Open Access Journals (Sweden)

    D. Burchart-Korol

    2014-07-01

    Full Text Available The main goal of the study was the analysis of the chemical compositions of raw materials used in iron ore sinter plants in Poland. The iron ore sintering process is the largest source of emissions of dust and gas pollution in the iron and steel industry. Hematite ores, magnetite concentrates, admixtures (dolomite, limestone and burnt lime, fuels (coke breeze, anthracite and by-products are used in Poland to produce the sinter mixture.

  1. Geological and Mineralogical-technological features chromite ore from nickel-weathering crusts Average Bug

    Directory of Open Access Journals (Sweden)

    Perkov E.S.

    2013-09-01

    Full Text Available Conditions of occurrence and distribution features of chromites ore bodies in the ultra-basic nickel bearing weathering crusts of Middle Bug Area are considered. Main types of exogenous chromites ores in weathering crusts and beyond of them are identified as well as mineralogical, chemical and grain features of mineralization are given. Obtained data are substantiated in order to apply them while developing the efficient schemes of mining and processing of exogenous chromites ores.

  2. Singular value decomposition approach to the yttrium occurrence in mineral maps of rare earth element ores using laser-induced breakdown spectroscopy

    Science.gov (United States)

    Romppanen, Sari; Häkkänen, Heikki; Kaski, Saara

    2017-08-01

    Laser-induced breakdown spectroscopy (LIBS) has been used in analysis of rare earth element (REE) ores from the geological formation of Norra Kärr Alkaline Complex in southern Sweden. Yttrium has been detected in eudialyte (Na15 Ca6(Fe,Mn)3 Zr3Si(Si25O73)(O,OH,H2O)3 (OH,Cl)2) and catapleiite (Ca/Na2ZrSi3O9·2H2O). Singular value decomposition (SVD) has been employed in classification of the minerals in the rock samples and maps representing the mineralogy in the sampled area have been constructed. Based on the SVD classification the percentage of the yttrium-bearing ore minerals can be calculated even in fine-grained rock samples.

  3. Microwave and Ultrasound Augmented Leaching of Complicated Zinc Oxide Ores in Ammonia and Ammonium Citrate Solutions

    Directory of Open Access Journals (Sweden)

    Libo Zhang

    2017-06-01

    Full Text Available Recovery of zinc from low grade zinc oxide ore is attempted with ammonia and ammonium citrate solutions augmented by microwave roasting and ultrasound radiation. The influence of the ammonia-ammonium ratio, roasting temperature, ultrasound power, and leaching time were assessed on the recovery of zinc. A maximum zinc recovery of 88.57% could be achieved at a roasting temperature of 673 K, leaching temperature of 298 K, stirring speed of 300 rpm, total ammonia concentration of 5 mol/L with an ammonium citrate concentration of 1.2 mol/L, liquid to solid ratio of 5:1, the ultrasound power was 600 W and the leaching time was 120 min. The enhancement in recovery with increases in the roasting temperature up to 673 K was attributed to the conversion of ZnCO3 to ZnO. The phases of mineral samples and the reaction residues were characterized by X-ray diffraction (XRD.

  4. Stabilization of chromium ore processing residue (COPR) with nanoscale iron particles.

    Science.gov (United States)

    Cao, Jiasheng; Zhang, Wei-Xian

    2006-05-20

    Laboratory batch experiments were conducted on heavily contaminated groundwater and chromium ore processing residue (COPR) samples to determine the rate and extent of hexavalent chromium [Cr(VI)] reduction and immobilization by nanoscale iron particles. Laboratory synthesized nanoscale iron particles (iron particles was 0.157 +/- 0.018 mg m(-2) min(-1), about 25 times greater than that by iron powders (100 mesh). One gram of nanoparticles can reduce 84.4-109.3mg Cr(VI) in the groundwater and 69.3-72.7 mg Cr(VI) in the COPR. This reduction capacity is 50-70 times greater than that of iron powders under the same experimental conditions.

  5. Timing of ore-related magmatism in the western Alaska Range, southwestern Alaska

    Science.gov (United States)

    Taylor, Ryan D.; Graham, Garth E.; Anderson, Eric D.; Selby, David

    2014-01-01

    This report presents isotopic age data from mineralized granitic plutons in an area of the Alaska Range located approximately 200 kilometers to the west-northwest of Anchorage in southwestern Alaska. Uranium-lead isotopic data and trace element concentrations of zircons were determined for 12 samples encompassing eight plutonic bodies ranging in age from approximately 76 to 57.4 millions of years ago (Ma). Additionally, a rhenium-osmium age of molybdenite from the Miss Molly molybdenum occurrence is reported (approx. 59 Ma). All of the granitic plutons in this study host gold-, copper-, and (or) molybdenum-rich prospects. These new ages modify previous interpretations regarding the age of magmatic activity and mineralization within the study area. The new ages show that the majority of the gold-quartz vein-hosting plutons examined in this study formed in the Late Cretaceous. Further work is necessary to establish the ages of ore-mineral deposition in these deposits.

  6. Phase transformation in reductive roasting of laterite ore with microwave heating

    Institute of Scientific and Technical Information of China (English)

    CHANG Yong-feng; ZHAI Xiu-jing; FU Yan; MA Lin-zhi; LI Bin-chuan; ZHANG Ting-an

    2008-01-01

    Selective reduction of laterite ores followed by acid leaching is a promising method to recover nickel and cobalt metal, leaving leaching residue as a suitable iron resource. The phase transformation in reduction process with microwave heating was investigated by XRD and the reduction degree of iron was analyzed by chemical method. The results show that the laterite samples mixed with active carbon couple well with microwave and the temperature can reach approximate 1 000 ℃ in 6.5 min. The reduction degree of iron is controlled by both the reductive agent content and the microwave heating time, and the reduction follows Fe2O3→Fe3O4→FeO→Fe sequence. Sulphuric acid leaching test reveals that the recoveries of nickel and iron increase with the iron reduction degree. By properly controlling the reduction degree of iron at 60% around, the nickel recovery can reach about 90% and iron recovery is less than 30%.

  7. Development and functioning of microorganisms in concentration cycles of sulfide copper-nickel and non-sulfide apatite-nepheline ores

    Directory of Open Access Journals (Sweden)

    Fokina N. V.

    2017-03-01

    Full Text Available The number and trophic diversity of bacteria in flotation samples of apatite-nepheline and sulfide copper-nickel ores at the concentration plants of JSC "Apatite" and Kola Mining and Metallurgical Company have been determined. The study of the size and diversity of the microbiota has been conducted by culture on selective nutrient media. The total number and biomass of bacteria have been considered by fluorescence microscopy using Cyclopore polycarbonate membrane filters. Bacteria have been identified by molecular genetic methods. The least amount of both saprotrophic and other trophic groups of bacteria has been observed in the samples of ore and recycled water as at the concentrating factory of Apatit JSC, and also at the plant "Pechenganikel". It has been found out that the bacteria contained in the ore and recycling water flowing from the tailings increased their number during the flotation process due to coming of the nutrients with the flotation reagents, aeration and increased temperature. Strains which occurrence is more than 60 % have been extracted from recycled water and basic flotation products and classified as Pseudomonas. Two strains with occurrence of more than 60 % have been discovered at Apatit JSC and classified as Stenotrophomonas and Acinetobacter. The number of fungi in the cycle of apatite-nepheline ore enrichment at the factories is very low (1 to 24 CFU / 1 ml or 1 g of ore. Fungi of the genus Penicillium have been dominated, fungi of the genera Acremonium, Aureobasidium, Alternaria, Chaetomium have also been detected. At the plant "Pechenganikel" species Aspergillus fumigatus, Penicillium aurantiogriseum and P. glabrum have been extracted. It has been shown that the bacteria deteriorate the apatite flotation as a result of their interaction with active centers of calcium-containing minerals and intensive flocculation decreasing the floatation selectivity. Also some trend of copper and nickel recovery change has been

  8. New insight into the origin of manganese oxide ore deposits in the Appalachian Valley and Ridge of northeastern Tennessee and northern Virginia, USA

    Science.gov (United States)

    Carmichael, Sarah K.; Doctor, Daniel H.; Wilson, Crystal G.; Feierstein, Joshua; McAleer, Ryan

    2017-01-01

    Manganese oxide deposits have long been observed in association with carbonates within the Appalachian Mountains, but their origin has remained enigmatic for well over a century. Ore deposits of Mn oxides from several productive sites located in eastern Tennessee and northern Virginia display morphologies that include botryoidal and branching forms, massive nodules, breccia matrix cements, and fracture fills. The primary ore minerals include hollandite, cryptomelane, and romanèchite. Samples of Mn oxides from multiple localities in these regions were analyzed using electron microscopy, X-ray analysis, Fourier transform infrared spectroscopy, and trace and rare earth element (REE) geochemistry. The samples from eastern Tennessee have biological morphologies, contain residual biopolymers, and exhibit REE signatures that suggest the ore formation was due to supergene enrichment (likely coupled with microbial activity). In contrast, several northern Virginia ores hosted within quartz-sandstone breccias exhibit petrographic relations, mineral morphologies, and REE signatures indicating inorganic precipitation, and a likely hydrothermal origin with supergene overprinting. Nodular accumulations of Mn oxides within weathered alluvial deposits that occur close to breccia-hosted Mn deposits in Virginia show geochemical signatures that are distinct from the breccia matrices and appear to reflect remobilization of earlier-emplaced Mn and concentration within supergene traps. Based on the proximity of all of the productive ore deposits to mapped faults or other zones of deformation, we suggest that the primary source of all of the Mn may have been deep seated, and that Mn oxides with supergene and/or biological characteristics resulted from the local remobilization and concentration of this primary Mn.

  9. O-Ring sealing arrangements for ultra-high vacuum systems

    Science.gov (United States)

    Kim, Chang-Kyo; Flaherty, Robert

    1981-01-01

    An all metal reusable O-ring sealing arrangement for sealing two concentric tubes in an ultra-high vacuum system. An O-ring of a heat recoverable alloy such as Nitinol is concentrically positioned between protruding sealing rings of the concentric tubes. The O-ring is installed between the tubes while in a stressed martensitic state and is made to undergo a thermally induced transformation to an austenitic state. During the transformation the O-ring expands outwardly and contracts inwardly toward a previously sized austenitic configuration, thereby sealing against the protruding sealing rings of the concentric tubes.

  10. New isotopic evidence bearing on bonanza (Au-Ag) epithermal ore-forming processes

    Science.gov (United States)

    Saunders, James A.; Mathur, Ryan; Kamenov, George D.; Shimizu, Toru; Brueseke, Matthew E.

    2016-01-01

    New Cu, S, and Pb isotope data provide evidence for a magmatic source of metal(loid)s and sulfur in epithermal Au-Ag deposits even though their ore-forming solutions are composed primarily of heated meteoric (ground) waters. The apparent isotopic discrepancy between ore metals and ore-forming solutions, and even between the ore and associated gangue minerals, indicates two different sources of epithermal ore-forming constituents: (1) a shallow geothermal system that not only provides the bulk of water for the ore-forming solutions but also major chemical constituents leached from host rocks (silica, aluminum, potassium, sodium, calcium) to make gangue minerals and (2) metals and metalloids (As, Te, Sb, etc.) and sulfur (±Se) derived from deeper magma bodies. Isotopic data are consistent with either vapor-phase transport of metal(loids) and sulfur and their subsequent absorption by shallow geothermal waters or formation of metallic (Au, Ag, Cu phases) nanoparticles at depth from magmatic fluids prior to encountering the geothermal system. The latter is most consistent with ore textures that indicate physical transport and aggregation of nanoparticles were significant ore-forming processes. The recognition that epithermal Au-Ag ores form in tectonic settings that produce magmas capable of releasing metal-rich fluids necessary to form these deposits can refine exploration strategies that previously often have focused on locating fossil geothermal systems.

  11. Effect of desliming on the flotation of a complax copper ore from China

    Directory of Open Access Journals (Sweden)

    Chen Yong

    2016-01-01

    Full Text Available The complex copper oxide ore sample was taken from Deerni copper deposit, Qinghai Province of China. Batch flotation tests had been conducted to upgrade the copper concentrate by conventional amyl xanthate reagents under 73% -74 μm of the particle size; however, the unsatisfied results (Cu grade of 18.21% and recovery of 59.25% were obtained. Also there are a large amount of slimes trapped in the concentrate and high-dosages consumption of reagents, for example, more than 2.5 kg/t sodium sulfide and 1.5 kg/t sodium silicate at only one-staged roughing. Based on the analysis of the sample, most of gangues are clay, feldspar and mica, which may easy to over-grind and deteriorate the flotation process either on reagents consumption or slurry fluidity or viscosity. A hydro-cyclone had been introduced to pre-concentrate the oxide ore by scrubbing the slime before flotation, which can result obviously in reducing the dosages of sodium sulfide from 2.5 Kg/t to 1 Kg/t, and raising the grade of Cu in the concentrate from 18.21% to 26.65% at the expense of about 1% recovery of Cu. In this paper, the effects on the recovery of Cu by the different dosages of flotation reagents with or without de-sliming were studied, with the objective of determining the different effects on the functions of flotation reagents by slime during flotation.

  12. Extraction of nickel from nickel limonite ore using dissolved gaseous SO2 - air

    Science.gov (United States)

    Wulandari, Winny; Soerawidjaja, Tatang Hernas; Joshua, Stephen; Isradi, Hashfi Rijal

    2017-01-01

    This paper reports a method of extracting nickel from nickel limonite by using dissolved SO2-air in ambient pressure. This method has been reported in the literature to be having advantages of a high selectivity of nickel towards iron, and can be conducted at ambient condition. The purpose of this study is to determine the good condition of nickel extraction from limonite ore by conducting pre-treatment and varying temperature and pH. The experiments were carried out in a five-neck reactor and comprised of three steps: pre-treatment of sample by pre-heating at 650 °C, leaching of the pre-treated sample, and analysis. The leaching solution was analyzed by using AAS (Atomic Absorption Spectrometer) method to determine the concentration of nickel and iron in the solution. The operating parameters included the acidity pH level of 3, 4, or 5 and the temperature of 30, 55, and 80 °C. The leaching was carried out up to 180 min. The mineralogical analysis of the ore was conducted by using XRD (X-Ray Diffraction) analysis. It is found that the good condition was obtained at pH 3, temperature of 80 °C, and 180 min leaching time, with nickel leaching efficiency of 21% from original nickel content. The selectivity nickel towards iron, defined by the extracted nickel (%) divided by extracted iron (%), has been found up to 2743. This method shows that nickel extraction can be carried out at very mild condition, including low temperature, atmospheric pressure and low pH.

  13. Is assimilation of country rocks in camera of crystallization an important factor for origin of the Noril'sk ores?

    Science.gov (United States)

    Krivolutskaya, Nadezhda; Kryazhev, Sergey; Svirskaya, Natalia

    2013-04-01

    In origin of the unique PGE-Cu Noril'sk deposits a great significance is attached to assimilation of country rocks by mafic melts in camera of crystallization for formation large-scale sulfide ore bodies. The main argument in favor of widespread assimilation is the enrichment of ore sulfides in the heavy sulfur isotope due to the participation of anhydrite from country rocks (Godlevsky, Grinenko, 1963). But real data demonstrated this process are almost absent in literature. We have studied geochemistry rocks of some sections from surrounding rocks to intrusive ones with sulfide ores. Two of them were done at the Southern Maslovsky deposit located in basalts and one was considered at Talnakh deposit (SW branch) that is situated among carbonate-terrigenouse rocks with evaporates (salt, anhydrite, gypsum). Ores at the Maslovsky deposit are characterized by δ34S = 6-11‰ while the host basalts of the Nadezhdinsky Formation have δ34S country basalts on composition of intrusive rocks is not detected at all and revealed in a narrow zone (country rocks by magma must be reflected in change of chemical and modal composition of intrusive rocks, especially in contact zones of intrusions, but this effect is noted established. Line of component variations have sharp profile from sedimentary rocks to gabbro-dolerites without intermediate values. It shows an absent of contamination in situ. Data on Nd, Sr, and Pb isotopic compositions of anydrite from the Devonian rocks demonstrate that the initial 87Sr/86Sr ratio (0.708637-0.708949, 251 Ma) in anhydrite is lower than in the Nadezhdinsky basalt, where this ratio attains 0.709171 (Wooden et al., 1993), The studied samples are characterized by anomalous enrichment in radiogenic lead (206Pb/204Pb attains 24.53). It would be expressed in isotopic composition of contaminated igneous rocks, but this is not the case. Thus, anhydrite cannot be a contaminant for igneous rocks and assimilation of country rocks in intrusive chambers was

  14. Helium, lead and sulfur isotope geochemistry of the Gejiu Sn-polymetallic ore deposit and the sources of ore-forming materials

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Studies on the helium, lead and sulfur isotopic composition were performed of the Gejiu super-large Sn-polymetallic ore deposit. The results indicated that the ore-forming materials came from different sources and the deposit is a product of superimposed mineralization. The deposit is characterized by multi-source and multi-period mineralization, which experienced submarine hydrothermal deposition and Late Yanshanian magmatic hydrothermal mineralization. It is held that the Gejiu super-large Sn-polymetallic ore deposit is a multi-genesis deposit.

  15. Cancer of the lung in iron ore (haematite) miners

    Science.gov (United States)

    Boyd, J. T.; Doll, R.; Faulds, J. S.; Leiper, J.

    1970-01-01

    Boyd, J. T., Doll, R., Faulds, J. S., and Leiper, J.(1970).Brit. J. industr. Med.,27, 97-105. Cancer of the lung in iron ore (haematite) miners. The mortality of Cumberland iron-ore miners has been studied by examining the death certificates of 5 811 men resident in two local authority areas (Ennerdale R.D. and Whitehaven M.B.) who died between 1948 and 1967. Comparison of the iron miners' experience with (1) that of other local men and (2) the relevant national experience has provided an assessment of the suspected occupational risk of lung cancer associated with haematite mining. During the 20-year period there were 42 deaths attributed to lung cancer among iron mine employees resident in the study area: 36 of these occurred in miners working underground, which was significantly greater than that expected from local non-mining (20·6 deaths) or national (21·5 deaths) experience. In contrast to these findings, there was no evidence of any excess mortality from lung cancer among surface workers and, for iron miners as a whole, mortality from other cancers was close to the national experience. A parallel analysis of mortality among coal miners showed a deficit of deaths from lung cancer in line with other studies. The patterns of other respiratory mortality in the two local mining groups were also in line with previous experience, and confirmed the existence of a substantial silicotic hazard associated with haematite mining in Cumberland. These findings strengthen previous necropsy evidence and indicate that West Cumberland iron-ore miners who work underground experience an occupational hazard of lung cancer. They suggest that the miners suffer a lung cancer mortality about 70% higher than `normal'. The risk may be due to radioactivity in the air of the mines (average radon concentration of 100 p Ci/litre) or to a carcinogenic effect of iron oxide. PMID:5448525

  16. Phase transformations of a talc ore under heated chlorine atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Orosco, P., E-mail: porosco@unsl.edu.ar [Instituto de Investigaciones en Tecnología Química (INTEQUI-CONICET), Chacabuco y Pedernera, 5700 San Luis (Argentina); Ruiz, M. del C. [Instituto de Investigaciones en Tecnología Química (INTEQUI-CONICET), Chacabuco y Pedernera, 5700 San Luis (Argentina); Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, 5700 San Luis (Argentina); González, J. [Instituto de Investigaciones en Tecnología Química (INTEQUI-CONICET), Chacabuco y Pedernera, 5700 San Luis (Argentina); Instituto de Ciencias Básicas, Universidad Nacional de Cuyo, Mendoza (Argentina)

    2013-02-20

    Highlights: ► We studied the effect of Cl{sub 2} on minerals present in a talc of ultramafic origin. ► Isothermal and non-isothermal assays were performed in N{sub 2} and Cl{sub 2}–N{sub 2} atmospheres. ► The reagents and the products were analyzed by DTA, XRD, SEM, and EPMA. ► The chlorination produced protoenstatite at 800 °C. ► Calcination of a talc ore in Cl{sub 2} produces more enstatite than thermal treatment in N{sub 2}. - Abstract: The effect of Cl{sub 2} on the phase transformations of the minerals present in a talc (Mg{sub 3}Si{sub 4}O{sub 10}(OH){sub 2}) unpurified with clinochlore (Mg{sub 5}Al{sub 2}Si{sub 3}O{sub 10}(OH){sub 8}), magnesite (MgCO{sub 3}), dolomite (MgCa(CO{sub 3}){sub 2}), hematite (Fe{sub 2}O{sub 3}) and pyrite (FeS{sub 2}) was studied with the purpose of deferricating the mineral and obtaining protoenstatite (MgSiO{sub 3}), which is the basic component of steatite ceramics. Isothermal and non-isothermal assays in N{sub 2} and Cl{sub 2}–N{sub 2} atmospheres were performed using a thermogravimetric device at temperatures between 600 and 980 °C. The reagents and the products were analyzed by differential thermal analysis (DTA), X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), and electron probe microanalysis (EPMA). Results obtained showed that the following phenomena were produced in Cl{sub 2}: (a) The transformation of vitreous silica (SiO{sub 2}), from the chlorination reaction of talc, into enstatite (MgSiO{sub 3}) started at about 700 °C, being dolomite the mineral that favored this reaction. At 800 °C, more enstatite was formed as a result of the reaction between vitreous silica not transformed, MgCl{sub 2} and O{sub 2} derived from the chlorination of dolomite and magnesite; then, polymorphic transformation of enstatite into protoenstatite was produced. (b) At about 950 °C, CaCl{sub 2} produced as a result of dolomite chlorination led to the destruction of the protoenstatite

  17. Thermal stress in North Western Australian iron ore mining staff.

    Science.gov (United States)

    Peiffer, Jeremiah J; Abbiss, Chris R

    2013-05-01

    Demand for Australian mined iron ore has increased employment within this sector, thus exposing increased numbers of workers to the harsh Australian climate. This study examined the influence of hot (>30°C wet bulb globe temperature) environmental temperatures, consistent with working in North Western Australia, on iron ore mining staff. Core temperature, hydration status, perceived exertion, mood, and fatigue state were measured in 77 participants at three time points (pre-, mid-, and post-shift) during a normal 12-h shift at an open-cut iron ore mining/processing site (n = 31; Site1) and an iron ore processing/shipping site (n = 46; Site2). A significant effect for time was observed for core temperature with greater mean core temperatures measured mid-shift (37.5±0.4°C) and post-shift (37.6±0.3°C) compared with pre-shift values (37.0±0.5°C). All mean core temperature measures were lower than ISO7933 thresholds (38°C) for thermal safety. Mean hydration measures [urine-specific gravity (USG)] were greater at Site1 (1.029±0.006) compared with those at Site2 (1.021±0.007). Furthermore, both pre- and post-shift measures from Site1 and the post-shift measures from Site2 were greater than the threshold for dehydration (USG = 1.020). No differences were observed for mood or perceived exertion over time; however, measures of fatigue state were greater post-shift compared with pre- and mid-shift values for both sites. Our findings indicate that the majority of mine workers in North Western Australia are able to regulate work rate in hot environments to maintain core temperatures below ISO safety guidelines; however, 22% of workers reached or exceeded the safety guidelines, warranting further investigation. Furthermore, hydration practices, especially when off-work, appear inadequate and could endanger health and safety.

  18. CHAIN EXTENDER AND EMULSIFIER APPLICATION IN IRON ORE FLOTATION

    Directory of Open Access Journals (Sweden)

    José Pedro da Silva

    2013-06-01

    Full Text Available The present study aims to evaluate the reverse flotation performance of iron ore, using collector (amine, in the presence and absence of chain extender (diesel oil and emulsifier (sodium lauryl sulfate.Six tests were realized with duplicate. Tests using amine, diesel oil and sodium lauryl sulphate show the better results, with metallurgical recovery of 91.82% and the concentrate silica equal 1.68%. Thus, it is found that the use of emulsifier and chain extender together with the amine, shows better results in the flotation, in terms of metal recovery and selectivity, when compared to using only amine or amine and diesel oil.

  19. Thermal Decomposition of Copper Ore Concentrate and Polyethylene Composites

    Science.gov (United States)

    Szyszka, Danuta; Wieckowska, Jadwiga

    2016-10-01

    Thermal analyses (TGA and DTA) of the composite, comprised of 10% polyethylene (PE) scrap and 90% copper ore concentrate, enabled determination of the temperature range and decomposition degree of the organic matters in argon atmosphere. Products of pyrolysis were qualitatively and quantitatively determined. The results were compared to those obtained for products of pyrolysis of the composite in air. Products of pyrolysis were identified by means of the gas chromatography (GC) method alone or supported with results of mass spectrometry analyses (GC-MS).

  20. TECHNOLOGICAL CHARACTERISTICS OF THE ZLATÁ BAŇA ORES

    Directory of Open Access Journals (Sweden)

    Košuth Marián

    1997-10-01

    Full Text Available The main processing interest of examined Zlatá Baňa polymetalic ores was focused on copper-lead-zinc minerals with precious metals and trace elements. Gold occurrin a native form or as an isomorphism in pyrite. The role of inclusions of own Ag-minerals was inflated by geologist, but a prevailing amount of silver is isomorphous in galena and argentotetrahedrite. Almost no possibility to concentrating discrete silver minerals was proved technologically. In galena, an interesting content of Se and Te was registered. Among trace elements, a higher content of cadmium folows exclusively the content of zinc in blende.

  1. Topological aperiodicity for product systems over semigroups of Ore type

    DEFF Research Database (Denmark)

    Kwasniewski, Bartosz; Szymanski, Wojciech

    2016-01-01

    We prove a version of uniqueness theorem for Cuntz-Pimsner algebras of discrete product systems over semigroups of Ore type. To this end, we introduce Doplicher-Roberts picture of Cuntz-Pimsner algebras, and the semigroup dual to a product system of 'regular' C*-correspondences. Under a certain...... aperiodicity condition on the latter, we obtain the uniqueness theorem and a simplicity criterion for the algebras in question. These results generalize the corresponding ones for crossed products by discrete groups, due to Archbold and Spielberg, and for Exel's crossed products, due to Exel and Vershik...

  2. Idea of Identification of Copper Ore with the Use of Process Analyser Technology Sensors

    Science.gov (United States)

    Jurdziak, Leszek; Kaszuba, Damian; Kawalec, Witold; Król, Robert

    2016-10-01

    The Polish resources of the copper ore exploited by the KGHM S.A. underground mines are considered as one of the most complex in the world and - consequently - the most difficult to be processed. The ore consists of three lithology forms: dolomites, shales and sandstones but in different proportions which has a significant impact on the effectiveness of the grinding and flotation processes. The lithological composition of the ore is generally recognised in-situ but after being mined it is blended on its long way from various mining fields to the processing plant by the complex transportation system consisting of belt conveyors with numerous switching points, ore bunkers and shafts. Identification of the lithological composition of the ore being supplied to the processing plant should improve the adjustments of the ore processing machinery equipment aiming to decrease the specific processing (mainly grinding) energy consumption as well as increase the metal recovery. The novel idea of Process Analyser Technology (PAT) sensors - information carrying pellets, dropped into the transported or processed bulk material which can be read directly when needed - is investigated for various applications within the DISIRE project (a part of the SPIRE initiative, acting under the Horizon2020 framework program) and here is adopted for implementing the annotation the transported copper ore for the needs of ore processing plants control. The identification of the lithological composition of ore blended on its way to the processing plant can be achieved by an information system consisting of pellets that keep the information about the original location of the portions of conveyed ore, the digital, geological database keeping the data of in-situ lithology and the simulation models of the transportation system, necessary to evaluate the composition of the blended ore. The assumptions of the proposed solution and the plan of necessary in-situ tests (with the special respect to harsh

  3. Impact of Dust from Ore Processing Facilities on Rain Water Collection Tanks in a Tropical Environment—The Obvious Source “Ain’t Necessarily So”

    Directory of Open Access Journals (Sweden)

    Brian Gulson

    2016-02-01

    Full Text Available Concerns have been expressed that dust from the minerals processing facilities at Karumba Queensland Australia have resulted in elevated lead (Pb concentrations in rain water tanks. The ores derived from the Century mine some 304 km from the port. High precision Pb isotopic measurements on environmental samples have been undertaken to evaluate the source of Pb in rainwaters and acid digests from roof wipes and gutter wipes. There does not appear to be any relationship between sample location and the processing facility but samples from the area subject to the prevailing winds show the highest contribution of Century Pb. All gutter wipes (82 to 1270 µg Pb/wipe have contributions of Century ore ranging from 87% to 96%. The contribution of Century ore to five roof wipes (22 to 88 µg Pb/wipe ranges from 89% to 97% and in the other two samples there is a mix of Century and Broken Hill Pb. Three of the seven rainwater have contributions of Century ore Pb ranging from 33% to 75%. Two of the other four rainwater samples have the highest water Pb concentrations of 88 and 100 µg/L and their isotopic data show Broken Hill Pb contributions ranging from 77% to 80%. The source of the Broken Hill Pb is probably from the galvanized roofing material and/or brass fittings in the rainwater tanks. The discrimination between various sources is only detectable using high precision 204Pb-based isotopic ratios and not the now common inductively coupled plasma mass spectrometry (ICP-MS data presentations of the higher abundance isotopes 208Pb, 207Pb and 206Pb. Isotopic results for the waters demonstrate that apportioning blame where there is an obvious point source may not always be the correct conclusion. Nevertheless the isotopic data for the gutter wipes indicates that there was widespread contamination from the processing facilities throughout the town.

  4. Impact of Dust from Ore Processing Facilities on Rain Water Collection Tanks in a Tropical Environment--The Obvious Source "Ain't Necessarily So".

    Science.gov (United States)

    Gulson, Brian; Korsch, Michael; Bradshaw, Anthony

    2016-02-22

    Concerns have been expressed that dust from the minerals processing facilities at Karumba Queensland Australia have resulted in elevated lead (Pb) concentrations in rain water tanks. The ores derived from the Century mine some 304 km from the port. High precision Pb isotopic measurements on environmental samples have been undertaken to evaluate the source of Pb in rainwaters and acid digests from roof wipes and gutter wipes. There does not appear to be any relationship between sample location and the processing facility but samples from the area subject to the prevailing winds show the highest contribution of Century Pb. All gutter wipes (82 to 1270 µg Pb/wipe) have contributions of Century ore ranging from 87% to 96%. The contribution of Century ore to five roof wipes (22 to 88 µg Pb/wipe) ranges from 89% to 97% and in the other two samples there is a mix of Century and Broken Hill Pb. Three of the seven rainwater have contributions of Century ore Pb ranging from 33% to 75%. Two of the other four rainwater samples have the highest water Pb concentrations of 88 and 100 µg/L and their isotopic data show Broken Hill Pb contributions ranging from 77% to 80%. The source of the Broken Hill Pb is probably from the galvanized roofing material and/or brass fittings in the rainwater tanks. The discrimination between various sources is only detectable using high precision (204)Pb-based isotopic ratios and not the now common inductively coupled plasma mass spectrometry (ICP-MS ) data presentations of the higher abundance isotopes (208)Pb, (207)Pb and (206)Pb. Isotopic results for the waters demonstrate that apportioning blame where there is an obvious point source may not always be the correct conclusion. Nevertheless the isotopic data for the gutter wipes indicates that there was widespread contamination from the processing facilities throughout the town.

  5. Study of Character and Trace of REE in Xiangshan Uranium Ore Field%相山铀矿田稀土元素地球化学特征及示踪研究

    Institute of Scientific and Technical Information of China (English)

    廖宇华

    2000-01-01

    Xiangshan Uranium ore fieled is a famous Volcanic type hydrothermal uranium ore field. The author studysgeochemical character of samples of REE of 4 reprentive uranium ores,of which are ore-host rock, uranium mine andpitchblende. This paper discusses material resource of rock-forming ore-forming, unveilings REE of uranium ore andmineralization of uranium of two difference geochemical types of mine,bring out relation of direct ratio, especialy urani-um and heavy REE in rich mine ore, which come from inner oviginal fluid and bring ont Co-precipitation. The strongeruranium-hydrothermal differntiation evolution is, the richer minerarli zation of uranium is.%相山铀矿田是我国著名的火山岩型热液铀矿田。作者对矿田4个有代表性的铀矿床的赋矿主岩、铀矿石、沥青铀矿样品稀土元素地球化学特征进行了研究,探讨了其成岩、成矿的物质来源,揭示了两种不同地球化学类型铀矿床的稀土元素与铀矿化呈正消长关系,尤其是富矿床中铀与重稀土元素,主要来自深部原生流体,并呈现出共沉淀的特点,含铀热液分异演化愈强,则铀矿化愈富。

  6. Variations in the uranium isotopic compositions of uranium ores from different types of uranium deposits

    Science.gov (United States)

    Uvarova, Yulia A.; Kyser, T. Kurt; Geagea, Majdi Lahd; Chipley, Don

    2014-12-01

    Variations in 238U/235U and 234U/238U ratios were measured in uranium minerals from a spectrum of uranium deposit types, as well as diagenetic phosphates in uranium-rich basins and peraluminous rhyolites and associated autunite mineralisation from Macusani Meseta, Peru. Mean δ238U values of uranium minerals relative to NBL CRM 112-A are 0.02‰ for metasomatic deposits, 0.16‰ for intrusive, 0.18‰ for calcrete, 0.18‰ for volcanic, 0.29‰ for quartz-pebble conglomerate, 0.29‰ for sandstone-hosted, 0.44‰ for unconformity-type, and 0.56‰ for vein, with a total range in δ238U values from -0.30‰ to 1.52‰. Uranium mineralisation associated with igneous systems, including low-temperature calcretes that are sourced from U-rich minerals in igneous systems, have low δ238U values of ca. 0.1‰, near those of their igneous sources, whereas uranium minerals in basin-hosted deposits have higher and more variable values. High-grade unconformity-related deposits have δ238U values around 0.2‰, whereas lower grade unconformity-type deposits in the Athabasca, Kombolgie and Otish basins have higher δ238U values. The δ234U values for most samples are around 0‰, in secular equilibrium, but some samples have δ234U values much lower or higher than 0‰ associated with addition or removal of 234U during the past 2.5 Ma. These δ238U and δ234U values suggest that there are at least two different mechanisms responsible for 238U/235U and 234U/238U variations. The 234U/238U disequilibria ratios indicate recent fluid interaction with the uranium minerals and preferential migration of 234U. Fractionation between 235U and 238U is a result of nuclear-field effects with enrichment of 238U in the reduced insoluble species (mostly UO2) and 235U in oxidised mobile species as uranyl ion, UO22+, and its complexes. Therefore, isotopic fractionation effects should be reflected in 238U/235U ratios in uranium ore minerals formed either by reduction of uranium to UO2 or chemical

  7. 40Ar-39Ar Dating of Quartz from Ore in the Baiyangping Cu-Co Polymetallic Ore-Concentrated Area, Lanping Basin, Yunnan

    Institute of Scientific and Technical Information of China (English)

    何明勤; 刘家军; 李朝阳; 李志明; 刘玉平; 杨爱平; 桑海清

    2004-01-01

    40Ar-39Ar fast neutron activation age spectrum of quartz in ore collected from the Baiyangping Cu-Co polymetallic ore-concentrated area, Lanping Basin, is saddle-shaped. The plateau age, minimum appearance age and isochron age shown on the spectra are 56.53±0.43 Ma, 55.52±1.78 Ma and 55.90±0.29 Ma respectively. The age data are consistent with each other within 1σ uncertainties. Because the given initial 40Ar/36Ar value of 294.7±1.14 is very close to Nier's value (295.5±5), both plateau and isochron ages may be considered as the forming time of quartz. So the age of 55.90-56.53 Ma represents the forming age of ore deposits. It is obvious that the ore deposits were formed during the Early Himalayan period.

  8. Remobilisation features and structural control on ore grade distribution at the Konkola stratiform Cu-Co ore deposit, Zambia

    Science.gov (United States)

    Torremans, K.; Gauquie, J.; Boyce, A. J.; Barrie, C. D.; Dewaele, S.; Sikazwe, O.; Muchez, Ph.

    2013-03-01

    The Konkola deposit is a high grade stratiform Cu-Co ore deposit in the Central African Copperbelt in Zambia. Economic mineralisation is confined to the Ore Shale formation, part of the Neoproterozoic metasedimentary rocks of the Katanga Supergroup. Petrographic study reveals that the copper-cobalt ore minerals are disseminated within the host rock, sometimes concentrated along bedding planes, often associated with dolomitic bands or clustered in cemented lenses and in layer-parallel and irregular veins. The hypogene sulphide mineralogy consists predominantly of chalcopyrite, bornite and chalcocite. Based upon relationships with metamorphic biotite, vein sulphides and most of the sulphides in cemented lenses were precipitated during or after biotite zone greenschist facies metamorphism. New δ34S values of sulphides from the Konkola deposit are presented. The sulphur isotope values range from -8.7‰ to +1.4‰ V-CDT for chalcopyrite from all mineralising phases and from -4.4‰ to +2.0‰ V-CDT for secondary chalcocite. Similarities in δ34S for sulphides from different vein generations, earlier sulphides and secondary chalcocite can be explained by (re)mobilisation of S from earlier formed sulphide phases, an interpretation strongly supported by the petrographic evidence. Deep supergene enrichment and leaching occurs up to a km in depth, predominantly in the form of secondary chalcocite, goethite and malachite and is often associated with zones of high permeability. Detailed distribution maps of total copper and total cobalt contents of the Ore Shale formation show a close relationship between structural features and higher copper and lower cobalt contents, relative to other areas of the mine. Structural features include the Kirilabombwe anticline and fault zones along the axial plane and two fault zones in the southern limb of the anticline. Cobalt and copper behave differently in relation to these structural features. These structures are interpreted to have

  9. Work stressors, job insecurity, union support, job satisfaction and safety outcomes within the iron ore mining environment

    Directory of Open Access Journals (Sweden)

    Nicolaas W.H. Smit

    2016-02-01

    Full Text Available Orientation: The study of work stressors, job insecurity and union support creates opportunity for iron ore mining organisations to manage job satisfaction and safety motivation and behaviour more effectively. Research purpose: The objective of this study was to investigate the relationship between work stressors, job insecurity, union support, job satisfaction and safety motivation and behaviour of a sample of iron ore mine workers in South Africa.Motivation for the study: The mining industry in general is often faced with hazardous and physically demanding working environments, where employees work under constant pressure. Work stressors, job insecurity, union support and job satisfaction are considered key variables when investigating effective means of managing safety.Research design, approach and method: A cross-sectional survey design was utilised to collect the data. A convenience sample of employees in the iron ore mining industry of South Africa (N = 260 were included. Structural equation modelling and bootstrapping resampling analysis were used to analyse the data.Main findings: Work stressors and job insecurity were found to be negatively associated with job satisfaction. Conversely, perceived union support was positively associated with job satisfaction and safety motivation and behaviour. Furthermore, job satisfaction mediated the relationship between union support and safety motivation and behaviour.Practical/managerial implications: Mining organisations can, by placing the focus on reducing work stressors, and promoting job security and union support, achieve higher levels of safety motivation and behaviour through job satisfaction.Contribution/value-add: A great deal of independent research on work stressors, job insecurity, union support, job satisfaction as well as safety motivation and behaviour has already been done. To date, very little empirical research exists that simultaneously considers all these constructs. This study

  10. Acidity measurement of iron ore powders using laser-induced breakdown spectroscopy with partial least squares regression.

    Science.gov (United States)

    Hao, Z Q; Li, C M; Shen, M; Yang, X Y; Li, K H; Guo, L B; Li, X Y; Lu, Y F; Zeng, X Y

    2015-03-23

    Laser-induced breakdown spectroscopy (LIBS) with partial least squares regression (PLSR) has been applied to measuring the acidity of iron ore, which can be defined by the concentrations of oxides: CaO, MgO, Al₂O₃, and SiO₂. With the conventional internal standard calibration, it is difficult to establish the calibration curves of CaO, MgO, Al₂O₃, and SiO₂ in iron ore due to the serious matrix effects. PLSR is effective to address this problem due to its excellent performance in compensating the matrix effects. In this work, fifty samples were used to construct the PLSR calibration models for the above-mentioned oxides. These calibration models were validated by the 10-fold cross-validation method with the minimum root-mean-square errors (RMSE). Another ten samples were used as a test set. The acidities were calculated according to the estimated concentrations of CaO, MgO, Al₂O₃, and SiO₂ using the PLSR models. The average relative error (ARE) and RMSE of the acidity achieved 3.65% and 0.0048, respectively, for the test samples.

  11. Stable Te isotope fractionation in tellurium-bearing minerals from precious metal hydrothermal ore deposits

    Science.gov (United States)

    Fornadel, Andrew P.; Spry, Paul G.; Haghnegahdar, Mojhgan A.; Schauble, Edwin A.; Jackson, Simon E.; Mills, Stuart J.

    2017-04-01

    The tellurium isotope compositions of naturally-occurring tellurides, native tellurium, and tellurites were measured by multicollector-inductively coupled plasma-mass spectrometry (MC-ICP-MS) and compared to theoretical values for equilibrium mass-dependent isotopic fractionation of representative Te-bearing species estimated with first-principles thermodynamic calculations. Calculated fractionation models suggest that 130/125Te fractionations as large as 4‰ occur at 100 °C between coexisting tellurates (Te VI) and tellurides (Te -II) or or native tellurium Te(0), and smaller, typically secondary emmonsite, δ130/125Te compositions were identical. The coincidence of δ130/125Te between all oxidized and reduced species in this study and the apparent lack of isotopic fractionation between native tellurium and emmonsite in one sample suggest that oxidation processes cause little to no fractionation. Because Te is predominantly transported as an oxidized aqueous phase or as a reduced vapor phase under hydrothermal conditions, either a reduction of oxidized Te in hydrothermal liquids or deposition of Te from a reduced vapor to a solid is necessary to form the common tellurides and native tellurium in ore-forming systems. Our data suggest that these sorts of reactions during mineralization may account for a ∼3‰ range of δ130/125Te values. Based on the data ranges for Te minerals from various ore deposits, the underpinning geologic processes responsible for mineralization seem to have primary control on the magnitude of fractionation, with tellurides in epithermal gold deposits showing a narrower range of isotope values than those in orogenic gold and volcanogenic massive sulfide deposits.

  12. Iron ore Development and supplies from Third world: A Potential for Sustainable Development.

    Directory of Open Access Journals (Sweden)

    Abdurrauf A. Ibrahim

    2014-12-01

    Full Text Available This paper discuss the qualitative leaching of iron ore in hydrochloric acid and multi gravity separation method as new strategies for reducing lost of iron during production. The focus of the paper is on the potential of iron ore development and supplies from Third world for Sustainable Development and to enter and sustain in the export global competitive Market..

  13. Methods of Dust Air Flows Reduction at Ore Transfer Facilities of Mining and Processing Plants

    Directory of Open Access Journals (Sweden)

    Gulmira K. Saparova

    2013-01-01

    Full Text Available The article describes the most typical schemes of ore stationary transfers. Aspirate units, depending on dust intensity are divided into three groups. Typical schemes of stationary transfers were presented. On the ground of the research, the classification of ore transfer facilities types at mining and processing plants was offered

  14. Market Structure Differences Impacting Australian Iron Ore and Metallurgical Coal Industries

    Directory of Open Access Journals (Sweden)

    Kurt Lawrence

    2015-07-01

    Full Text Available Steelmaking relies on iron ore and metallurgical coal as main ingredients, the trade of which is hypothesized to theoretically change in tandem. However, strong correlation is not evident in historical trade prices of steelmaking inputs. To determine causes to this occurrence, the market factors that influence the Australian iron ore and metallurgical coal industries were studied. Data was collected over the past decade for worldwide resource production and trade quantities of crude steel, iron ore, and metallurgical coal. The data was analysed to reveal trends, allowing examination of the macroeconomic trade of metallurgical coal and iron ore with relation to worldwide and country specific steel production. It was determined that the influential growth of China’s steel production has spurred the growth of worldwide iron ore demand, which was met with increased production and supply, from Australia. The increased metallurgical coal demand has been met with increased production within China locally. Measures of supply elasticity were created for worldwide iron ore and metallurgical coal trade, where comparisons between Australia’s industries to the relevant greatest competitor were examined. The results, along with respective resource production data, highlighted the elevated competitive position that Australian iron ore producers enjoy compared to metallurgical coal producers. Trade characteristics revealed the different market structures that iron ore and metallurgical coal industries operate in, prompting a discussion of the effects these markets have on the two Australian industries.

  15. 40 CFR 440.30 - Applicability; description of the uranium, radium and vanadium ores subcategory.

    Science.gov (United States)

    2010-07-01

    ... for the extraction of uranium, radium and vanadium. Only vanadium byproduct production from uranium... uranium, radium and vanadium ores subcategory. 440.30 Section 440.30 Protection of Environment... SOURCE CATEGORY Uranium, Radium and Vanadium Ores Subcategory § 440.30 Applicability; description of...

  16. Relaxation phenomena and jointing in ore bodies under explosive injection treatment

    Science.gov (United States)

    Shevchenko, YuS

    2017-02-01

    Under analysis are relaxation phenomena in ore bodies under leaching. It is shown that liquid and gas–liquid phases make these phenomena last longer, thus it is recommended to apply synergetically interconnected processes of explosive fracture of an ore block and simultaneous injection of active leaching solutions in the generated system of joints.

  17. Tungsten and Molybdenum Ores in China and the Management Policies(Part Ⅰ)

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>China is traditionally a leading producer of tungsten and molybdenum ores in the world. The ores are densely distributed and easy to exploit,and the production accounts for a large share of the world’s total.But China has yet to dominate the market and the advantage that China has long enjoyed is being weakened,giv-

  18. Silicophosphate Sorbents, Based on Ore-Processing Plants' Waste in Kazakhstan

    Science.gov (United States)

    Kubekova, Sholpan N.; Kapralova, Viktoria I.; Telkov, Shamil A.

    2016-01-01

    The problem of ore-processing plants' waste and man-made mineral formations (MMF) disposal is very important for the Republic of Kazakhstan. The research of various ore types (gold, polymetallic, iron-bearing) MMF from a number of Kazakhstan's deposits using a complex physical and chemical methods showed, that the waste's main components are…

  19. The gold contained in imported lead ore concentrate is exempted from import value-added tax

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>According to the No. 14 proclamation issued by Customs Service, as from April 1st 2007, the importation of galena and the lead ore concentrate will enjoy the favorable policy intended for associated gold deposits, i.e. the value-added tax for gold component in the imported galena and lead ore concentrate is exempted,

  20. Simulating Some Complex Phenomena in Hydrothermal Ore-Forming Processes by Reaction-Diffusion CNN

    Institute of Scientific and Technical Information of China (English)

    Xu Deyi; Yu Chongwen; Bao Zhengyu

    2003-01-01

    Complexity phenomena like dynamic and static patterns, order from disorder, chaos and catastrophe were simulated by the application of 2-D reaction-diffusion CNN of two state variables and two diffusion coefficients transformed from Zhabotinksii model. They revealed somehow the mechanism of hydrothermal ore-forming processes, and answered several questions about the onset of ore forming.

  1. Application of neodymium isotope ratio measurements for the origin assessment of uranium ore concentrates

    NARCIS (Netherlands)

    Krajko, J.; Varga, Z.; Yalcintas, E.; Wallenius, M.; Mayer, K.

    2014-01-01

    A novel procedure has been developed for the measurement of 143Nd/144Nd isotope ratio in various uranium-bearing materials, such as uranium ores and ore concentrates (UOC) in order to evaluate the usefulness and applicability of variations of 143Nd/144Nd isotope ratio for provenance assessment in nu

  2. Reduction of Low-grade Manganese Dioxide Ore Pellets by Biomass Wheat Stalk

    Institute of Scientific and Technical Information of China (English)

    Honglei ZHANG; Guocai ZHU; Hong YAN; Yuna ZHAO; Tiancheng LI; Xiujuan FENG

    2013-01-01

    An investigation on reducing low-grade manganese dioxide ore pellets was carried out by using wheat stalk as reductant.The main impact factors of reduction percent such as particle size,biomass/ore ratio,heating rate,nitrogen flow rate,temperature and time in reduction process were discussed.The morphology and component of manganese dioxide ore particle at different stages were also analyzed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS).The results show the increase of the reduction temperature and time,biomass/ore ratio,and the decrease of particle size,heating rate and nitrogen flow rate can significantly enhance reduction efficiency.The reduction kinetic of the manganese ore is controlled by three-dimensional mass diffusion of gaseous reductive volatiles passing from the surface to the core of the ore particles.The activation energy E and frequency factor A were calculated to be 24.15 kJ.mol-1 and 166 min-1,respectively.Biomass pyrolysis volatiles adsorbed onto the surface of the ore particle leads to serious variation of the microstructures and chemical composition of the manganese ore particles.

  3. Preparation of ore blocks for mine leaching by reagent explosion injection

    Science.gov (United States)

    Shevchenko, YuS

    2017-02-01

    The current drilling-and-blasting operations fail to prepare intact ore body underlying a production horizon for subsequent mining and leaching. It is found that the required preparation quality is possible by means of advanced implementation of ore body discontinuity and filling of the resultant system of joints with active leaching solutions.

  4. Depreciation in Ambient Air Quality in Iron Ore Mining Region of Goa

    Directory of Open Access Journals (Sweden)

    Gurdeep Singh

    2015-04-01

    Full Text Available Goa is one of the most famous international tourist destinations of the world. Export of Iron ore extracted from the midland of Goa is a major economic activity. However, there is a serious concern of air pollution due to iron ore mining activities. In order to assess the impact of mining activities on the environmental regime, the air quality depreciation index was adopted for this study due to its realistic and meaningful presentation of deterioration in ambient air quality. The index had been applied to the ambient air quality monitoring results of thirty four locations in the iron ore mining region of Goa. To envisage upon the deterioration in air quality due to various activities, eight stations were selected around mines, twelve in the buffer zone (within 4 Km radius of the core mining activities and fourteen along the ore transportation routes for monitoring of SPM, PM10, SO2 and NOX. The deterioration of air quality in the iron ore mining region of Goa is clearly apparent as the depreciation in air quality was found < -1 from the most desired value of 0 at all the stations. In general, the air quality was found most depreciated along the ore transportation routes, which is also evidenced by a considerable load of particulate matters observed. This infers that ore transportation is the most devastating activity in the iron ore mining region of Goa and accordingly mitigation plan should be adopted.

  5. Accelerating column leaching trial on copper sulfide ore

    Institute of Scientific and Technical Information of China (English)

    WANG Hongjiang; WU Aixiang; ZHOU Xun; WANG Shaoyong; ZHANG Jie

    2008-01-01

    The main measures to accelerate leaching sulfide ore are large spraying intensity,manual oxygen supply,temperature control and acclimated bacteria.The indoor experiment accelerating sulfide ore leaching detected the temperature during leaching process,dissolvability of oxygen,bacterial concentration,Cu concentration and slag grade.At the same time,this paper also analyzed the effect of four factors,which are bacterial diversity cultivation stage,spraying intensity,air supply,and whether to control temperature,on the leaching efficiency of copper.The results indicate that the oxygen content of leach solution has a close relationship with temperature but it is rarely affected by air supply.The bacterial concentration preserves from 106 to 107 mL-1,and temperature has a great effect on the bacterial activity under the condition of proper temperature and oxygen supply,and the lack of nutrition prevents the bacterial concentration from rising in the late stage.The relationships of the copper leaching efficiency to temperature,air feed,and spraying intensity are directly proportional.The leaching efficiencies of the cultivated bacteria and acclimation bacteria are 1.2 and 1.4 times as large as that of the original bacteria.

  6. Application of natural analog studies to exploration for ore deposits

    Energy Technology Data Exchange (ETDEWEB)

    Gustafson, D.L. [Consulting Economic Geologist, Reno, NV (United States)

    1995-09-01

    Natural analogs are viewed as similarities in nature and are routinely utilized by exploration geologists in their search for economic mineral deposits. Ore deposit modeling is undertaken by geologists to direct their exploration activities toward favorable geologic environments and, therefore, successful programs. Two types of modeling are presented: (i) empirical model development based on the study of known ore deposit characteristics, and (ii) concept model development based on theoretical considerations and field observations that suggest a new deposit type, not known to exist in nature, may exist and justifies an exploration program. Key elements that are important in empirical model development are described, and examples of successful applications of these natural analogs to exploration are presented. A classical example of successful concept model development, the discovery of the McLaughlin gold mine in California, is presented. The utilization of natural analogs is an important facet of mineral exploration. Natural analogs guide explorationists in their search for new discoveries, increase the probability of success, and may decrease overall exploration expenditure.

  7. Phytostabilization of iron ore tailings through Calophyllum inophyllum L.

    Science.gov (United States)

    Chaturvedi, Nilima; Dhal, N K; Reddy, Palli Sita Rama

    2012-12-01

    The phytostabilization of waste material generated during mining and processing of iron ore through Calophyllum inophyllum L. have been investigated. Iron ore tailings and its varying composition with garden soil were taken to study plant growth, chlorophyll content and metal uptake pattern of Calophyllum inophyllum L. These studies indicate that 100% survival of plant species was noted in all the treatments without any toxicity symptoms. The increase in growth parameters and chlorophyll content along with the high metal accumulation in plant tissues suggests that Calophyllum inophyllum L. may be a potential tool for phytoremediation. The accumulation of Pb (1662 microgm/gm) and Fe (2313 microgm/gm) was observed to be maximum in the plant tissues followed by Cu, Zn, Cr, and Ni. The TF values for most of the heavy metals was observed to be > 1 which indicates that the plant can efficiently translocate these toxic metals to its above ground parts. Removal of more than 30% of the most of the heavy metal like Fe, Pb, and Cu & Zn has been observed in all the treatments during one year of observation. The overall study clearly suggests that the plant can be used as an efficient tool for restoration of mining wastes and other similarly contaminated sites.

  8. Analyzing the international exergy flow network of ferrous metal ores.

    Science.gov (United States)

    Qi, Hai; An, Haizhong; Hao, Xiaoqing; Zhong, Weiqiong; Zhang, Yanbing

    2014-01-01

    This paper employs an un-weighted and weighted exergy network to study the properties of ferrous metal ores in countries worldwide and their evolution from 2002 to 2012. We find that there are few countries controlling most of the ferrous metal ore exports in terms of exergy and that the entire exergy flow network is becoming more heterogeneous though the addition of new nodes. The increasing of the average clustering coefficient indicates that the formation of an international exergy flow system and regional integration is improving. When we contrast the average out strength of exergy and the average out strength of currency, we find both similarities and differences. Prices are affected largely by human factors; thus, the growth rate of the average out strength of currency has fluctuated acutely in the eleven years from 2002 to 2012. Exergy is defined as the maximum work that can be extracted from a system and can reflect the true cost in the world, and this parameter fluctuates much less. Performing an analysis based on the two aspects of exergy and currency, we find that the network is becoming uneven.

  9. Analyzing the International Exergy Flow Network of Ferrous Metal Ores

    Science.gov (United States)

    Qi, Hai; An, Haizhong; Hao, Xiaoqing; Zhong, Weiqiong; Zhang, Yanbing

    2014-01-01

    This paper employs an un-weighted and weighted exergy network to study the properties of ferrous metal ores in countries worldwide and their evolution from 2002 to 2012. We find that there are few countries controlling most of the ferrous metal ore exports in terms of exergy and that the entire exergy flow network is becoming more heterogeneous though the addition of new nodes. The increasing of the average clustering coefficient indicates that the formation of an international exergy flow system and regional integration is improving. When we contrast the average out strength of exergy and the average out strength of currency, we find both similarities and differences. Prices are affected largely by human factors; thus, the growth rate of the average out strength of currency has fluctuated acutely in the eleven years from 2002 to 2012. Exergy is defined as the maximum work that can be extracted from a system and can reflect the true cost in the world, and this parameter fluctuates much less. Performing an analysis based on the two aspects of exergy and currency, we find that the network is becoming uneven. PMID:25188407

  10. Dynamic Testing and Properties of Rubber O-rings and Their Application in Soft Drop Weight Tests of Low Strength Materials /

    OpenAIRE

    2014-01-01

    Mechanical behavior of low strength materials and elements at high strain rates was studied using a drop tower at UCSD. A commercial drop tower was modified to conduct high strain-rate impact compression tests. Instrumentations including strain gauges, accelerometers and a high speed camera were used to establish equilibrium conditions and stress strain relation of samples with high accuracy. Dynamic response of strongly nonlinear, viscoelastic toroidal rubber elements (o-rings) is studied. N...

  11. Geology and ore fluid geochemistry of the Jinduicheng porphyry molybdenum deposit, East Qinling, China

    Science.gov (United States)

    Li, Hongying; Ye, Huishou; Wang, Xiaoxia; Yang, Lei; Wang, Xiuyuan

    2014-01-01

    Jinduicheng deposit is a giant Mesozoic porphyry Mo system deposit in the East Qinling molybdenum belt, Shaanxi Province, China. The mineralization is associated with the I-type Jinduicheng granite porphyry. Both the porphyry stock and country rocks underwent intense hydrothermal alteration. The alteration, with increasing distance from the parent intrusion, changes from silicification, through potassic and phyllic assemblages, carbonation, to propylitic assemblages. Molybdenite, the dominant ore mineral, occurs in veinlets, most of which are hosted by the altered country rocks, with less than 25% of the ore in the porphyry body. The hydrothermal system comprises four stages, including pre-ore quartz and K-feldspar; two ore stages of quartz, K-feldspar, molybdenite, and Pb- And Zn-bearing sulfides; and post-ore quartz and carbonate. Six main types of primary fluid inclusions are present in hydrothermal quartz, including two-phase aqueous, one-phase aqueous, three-phase CO2-bearing, CO2-dominated fluid inclusions, gas inclusions, and melt inclusions. The homogenization temperatures of fluid inclusions range from 210 to 290 °C in the pre-ore stage, 150-310 °C in ore stage I, 150-360 °C in the ore stage II, and 195-325 °C in the post-ore stage quartz. Estimated salinities of the ore-forming fluids range from 6.9 to 13.5, 4.3 to 12.3, 6.2 to 12.4, and 3.4 to 9.9 wt.% NaCl equiv. in stages 1-4, respectively. The δ34S values of pyrite in the two ore stages range from 2.8‰ to 4.3‰, whereas the δ34S values of molybdenite range from 2.9‰ to 6.2‰. The data suggest both magmatic and crustal sources of sulfur. The δD and δ18O values for the hydrothermal fluids are -57.2‰ to -84.4‰ and 8.0‰ to -3.2‰, respectively. The fluid inclusion and stable data indicate that the pre-ore hydrothermal fluids were mostly of magmatic origin, but the fluids responsible for ore deposition were mixed magmatic and meteoric, and eventually meteoric water dominated the system

  12. LIFETIME PREDICTION FOR MODEL 9975 O-RINGS IN KAMS

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, E.; Skidmore, E.

    2009-11-24

    The Savannah River Site (SRS) is currently storing plutonium materials in the K-Area Materials Storage (KAMS) facility. The materials are packaged per the DOE 3013 Standard and transported and stored in KAMS in Model 9975 shipping packages, which include double containment vessels sealed with dual O-rings made of Parker Seals compound V0835-75 (based on Viton{reg_sign} GLT). The outer O-ring of each containment vessel is credited for leaktight containment per ANSI N14.5. O-ring service life depends on many factors, including the failure criterion, environmental conditions, overall design, fabrication quality and assembly practices. A preliminary life prediction model has been developed for the V0835-75 O-rings in KAMS. The conservative model is based primarily on long-term compression stress relaxation (CSR) experiments and Arrhenius accelerated-aging methodology. For model development purposes, seal lifetime is defined as a 90% loss of measurable sealing force. Thus far, CSR experiments have only reached this target level of degradation at temperatures {ge} 300 F. At lower temperatures, relaxation values are more tolerable. Using time-temperature superposition principles, the conservative model predicts a service life of approximately 20-25 years at a constant seal temperature of 175 F. This represents a maximum payload package at a constant ambient temperature of 104 F, the highest recorded in KAMS to date. This is considered a highly conservative value as such ambient temperatures are only reached on occasion and for short durations. The presence of fiberboard in the package minimizes the impact of such temperature swings, with many hours to several days required for seal temperatures to respond proportionately. At 85 F ambient, a more realistic but still conservative value, bounding seal temperatures are reduced to {approx}158 F, with an estimated seal lifetime of {approx}35-45 years. The actual service life for O-rings in a maximum wattage package likely lies

  13. Paragenetic and minor- and trace-element studies of Mississippi Valley-type ore deposits of the Silesian-Cracow district, Poland

    Science.gov (United States)

    Viets, J.G.; Leach, D.L.; Lichte, F.E.; Hopkins, R.T.; Gent, C.A.; Powell, J.W.

    1996-01-01

    Paragenetic and minor- and trace-element studies were conducted on samples of epigenetic ore and gangue minerals collected from mines and drill core in the Silesian-Cracow (S-C) district of southern Poland. Four discrete mineral suites representing four mineralizing stages can be identified throughout the district. The earliest epigenetic minerals deposited during stage 1 consist of a late dolomite cement together with minor pyrite and marcasite. Stage 2 was the first ore-forming stage and included repetitive deposition of sphalerite and galena in a variety of morphologies. Stage 3 abruptly followed the first ore stage and deposited marcasite and pyrite with variable amounts of late sphalerite and galena. In the samples studied, minerals deposited during stage 3 are predominately marcasite-pyrite with minor sphalerite and galena in the Pomorzany and Olkusz mines, whereas, at the Trzebionka mine, stage 3 mineralization deposited mostly galena and sphalerite with little marcasite or pyrite. Stage 4 minerals include contains barite, followed by calcite, with very minor pyrite and a rare, late granular sphalerite. Compared to other major Mississippi Valley-type (MVT) districts of the world, the Silesian-Cracow district contains sphalerite with the second largest range in Ag concentrations and the largest range in Fe and Cd concentrations of any district. Unlike in other districts, very wide ranges in minor- and trace-element concentrations are also observed in paragenetically equivalent samples collected throughout the district. This wide range indicates that the minor- and trace-element content of the ore-forming environment was highly variable, both spatially and temporally, and suggests that the hydrologic system that the ore fluids traversed from their basinal source was very complex. Throughout the district, a significant increase in Tl, Ge, and As concentrations is accompanied by a lightening of sulfur isotopes between stage 2 and stage 3 minerals. This change

  14. Technology of Polish copper ore beneficiation – perspectives from the past experience

    Directory of Open Access Journals (Sweden)

    Wieniewski Andrzej

    2016-01-01

    Full Text Available The paper describes the main types of existing copper deposits in the world and the most common enrichment technologies. The characteristic elements of the current flowsheet of the Polish ore beneficiation were discussed together with the reasons for using them. The paper presents a perspective flowsheet based on more than 50-years of experience in beneficiation of Polish copper ore. The main elements of proposed technology are: leaving in justified cases the division of ore into fractions of increased sandstone and carbonate ores content, flotation in the milling circuit as part of the effective preparation of the ore to rougher flotation, intensive rougher flotation, classic cleaning system, processing of the middlings with grinding system in new type mills, classification and flotation with outlet of final tailings.

  15. Iron ore tailings used for the preparation of cementitious material by compound thermal activation

    Institute of Scientific and Technical Information of China (English)

    Zhong-lai Yi; Heng-hu Sun; Xiu-quan Wei; Chao Li

    2009-01-01

    In the background of little reuse and large stockpile for iron ore railings, iron ore tailing from Chinese Tonghua were used as raw material to prepare cementitious materials. Cementitious properties of the iron ore tailings activated by compound thermal ac-tivation were studied. Testing methods, such as XRD, TG-DTA, and IR were used for researching the phase and structure variety of the iron ore tailings in the process of compound thermal activation. The results reveal that a new cementitious material that contains 30wt% of the iron ore tailings can be obtained by compounded thermal activation, whose mortar strength can come up to the stan-dard of 42.5 cement of China.

  16. Genetic characteristics of fluid inclusions in sphalerite from the Silesian-Cracow ores, Poland

    Science.gov (United States)

    Kozlowski, A.; Leach, D.L.; Viets, J.G.

    1996-01-01

    Fluid inclusion studies in sphalerite from early-stage Zn-Pb mineralization in the Silesian-Cracow region (southern Poland), yielded homogenization temperatures (Th) from 80 to 158??C. Vertical thermal gradient of the parent fluids was 6 to 10??C, and the ore crystallization temperature ranges varied from recrystallization of ores, and Th distribution in single fissure fillings were considered. The ore-forming fluids were liquid-hydrocarbon-bearing aqueous solutions of Na-Ca-Cl type with lower Ca contents in the south and higher Ca contents in the north of the region. The ore-forming fluids had salinities from nul to about 23 weight percent of NaCl equivalent. Three types of fluids were recognized, that mixed during ore precipitation: a) ascending fluids of low-to-moderate salinity and high, b) formation brines of high salinity and moderate Th, and c) descending waters of low salinity and low-to-moderate Th.

  17. Butyl rubber O-ring seals: Revision of test procedures for stockpile materials

    Energy Technology Data Exchange (ETDEWEB)

    Domeier, L.A.; Wagter, K.R.

    1996-12-01

    Extensive testing showed little correlation between test slab and O-ring performance. New procedures, comparable to those used with the traditional test slabs, were defined for hardness, compression set, and tensile property testing on sacrificial O-ring specimens. Changes in target performance values were made as needed and were, in one case, tightened to reflect the O-ring performance data. An additional study was carried out on O-ring and slab performance vs cure cycle and showed little sensitivity of material performance to large changes in curing time. Aging and spectra of certain materials indicated that two sets of test slabs from current vendor were accidently made from EPDM rather than butyl rubber. Random testing found no O-rings made from EPDM. As a result, and additional spectroscope test will be added to the product acceptance procedures to verify the type of rubber compound used.

  18. EXPERIMENTAL STUDY ON THE LOAD DECAY AND ITS EFFECT ON LEAK RATE OF O-RING

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Experimental studies on load decay and leak rate of O-rings made of two kinds of silicone rubber are conducted. The results show that the characteristic of load decay is relative to the material and temperature of O-rings; the rate of load decay increases with the rise of temperature; the effects of load decay on leak rate of O-rings are negligible at room temperature, but they are notable at high temperature, and they are related to the material of O-rings. On the basis of study on the theory of load decay and analysis to the results of experiments, a theoretical model is developed to describe the load decay characteristic of O-rings, and it matches the experimental data very well. By the study of time-temperature equivalence of load decay, the interconvertting equation of test data of load decay at different temperatures is obtained.

  19. Thermodynamic Analysis of the Selective Reduction of a Nickeliferous Limonitic Laterite Ore by Hydrogen

    Science.gov (United States)

    Elliott, R.; Pickles, C. A.

    2017-09-01

    Nickeliferous limonitic laterite ores are becoming increasingly attractive as a source of metallic nickel as the costs associated with recovering nickel from the sulphide ores increase. Unlike the sulphide ores, however, the laterite ores are not amenable to concentration by conventional mineral processing techniques such as froth flotation. One potential concentrating method would be the pyrometallurgical solid state reduction of the nickeliferous limonitic ores at relatively low temperatures, followed by beneficiation via magnetic separation. A number of reductants can be utilized in the reduction step, and in this research, a thermodynamic model has been developed to investigate the reduction of a nickeliferous limonitic laterite by hydrogen. The nickel recovery to the ferronickel phase was predicted to be greater than 95 % at temperatures of 673-873 K. Reductant additions above the stoichiometric requirement resulted in high recoveries over a wider temperature range, but the nickel grade of the ferronickel decreased.

  20. Role of minerals properties on leaching process of weathered crust elution-deposited rare earth ore

    Institute of Scientific and Technical Information of China (English)

    肖燕飞; 刘向生; 冯宗玉; 黄小卫; 黄莉; 陈迎迎; 吴文远

    2015-01-01

    Granite belonged to intrusive rock and volcanic was extrusive rock. There may be many differences in their degree of weathering and mineral chemical composition. The present study investigated the minerals properties and the leaching mechanism of the granitic weathered crust elution-deposited rare earth ore from Longnan Rare Earth Mine area (LN ores) and volcanic weathered crust elution-deposited rare earth ore from Liutang Rare Earth Mine area (LT ores). The X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) were used to characterize the phase of rare earth ores. The particle size distributions and main composition of the ore were also presented in this paper. The leaching mechanisms of two kinds of rare earth ores were analyzed with different kinetics models and could be described by the shrinking-core model. They were all inner diffusion-controlled leaching processes. The leaching equation of the kinetics of the LN ores could be expressed as:4 LN LN 1.096 10 2/3 0.377 8.314 0 2 3=0.1061 (1 ) Tr e tη η×−−− − −, leaching equation of kinetics of LT ores was 3 LT LT 4.640 10 2/3 0.411 8.314 0 32 3=8.33 101 (1 ) Tr e tη η×−− −×− − −. The rare earth leaching rate of LT ores was always lower in the same condition, and it would need more time and more (NH4)2SO4 consump-tion to achieve the same rare earth leaching efficiency, which would lead to more serious ammonia-nitrogen pollution. Therefore, magnesium salt was proposed as the leaching agent to eliminate ammonia-nitrogen pollution and further studies would be taken in the future.

  1. Anisotropy of remanent and induced magnetization in hematite ore deformed in torsion

    Science.gov (United States)

    Machek, Matěj; Petrovský, Eduard; Roxerová, Zuzana; Kusbach, Vladimír; Siemes, Heinrich

    2016-04-01

    Induced and remanent magnetization measurements, e.g. shape of hysteresis loops, FORC diagrams and decomposition of isothermal remanent magnetization (IRM) acquisition curves, became routine tools in rock-magnetic measurements, interpreted mostly in terms of composition and grain-size distribution of iron oxides. It is assumed that the substances investigate are with respect to these measurements isotropic and single measurement of one sample is sufficient for interpretation. This assumption is valid for powdered samples, but solid rock samples in general behave anisotropically. In our contribution we report on magnetic measurements of hematite ore samples deformed in torsion, which show significant anisotropy of shape of hysteresis loops and IRM acquisition curves; the degree of anisotropy reflecting the degree of deformation. Samples, measured in different directions, showed different shape of hysteresis loop, from regular, which may be interpreted either as randomly oriented multi-domain grains, or with different degree of distortion (wasp-waistedness), reflecting different distribution of contrasting coercivities. Also decomposition of IRM acquisition curves, measured in different direction, yielded different interpretation in terms of relative contributions of components with different coercivities. The increasing strain is reflected in the strength and orientation of microstructure and crystallographic preferred orientation (CPO). The AMS in deformed samples is not controlled by hematite CPO. It is rather dominated by occurrence of magnetite grains along samples edges parallel to shear plane, probably due to the diffusion of Fe ions from iron jacket, even though samples were shielded by a silver (70)/palladium (30) sleeve of 0.5 mm thickness. We interpret this anisotropy as result of deformation, causing preferred orientation of basal planes of hematite. Moreover, the anisotropy is asymmetric. Our results suggest that, at least in deformed rocks containing

  2. 20 CFR 404.1084 - Gain or loss from disposition of property; capital assets; timber, coal, and iron ore...

    Science.gov (United States)

    2010-04-01

    ...; capital assets; timber, coal, and iron ore; involuntary conversion. 404.1084 Section 404.1084 Employees... from disposition of property; capital assets; timber, coal, and iron ore; involuntary conversion. (a... disposal of iron ore mined in the United States, even if held primarily for sale to customers, if section...

  3. 78 FR 47317 - Ore Knob Mine Superfund Site; Laurel Springs, Ashe County, North Carolina; Notice of Settlement

    Science.gov (United States)

    2013-08-05

    ... AGENCY Ore Knob Mine Superfund Site; Laurel Springs, Ashe County, North Carolina; Notice of Settlement... Protection Agency has entered into a settlement with Herbert N. Francis concerning the Ore Knob Mine... comments by site name ``Ore Knob Mine Superfund Site'' by one of the following methods:...

  4. Integration of coal pyrolysis process with iron ore reduction:Reduction behaviors of iron ore with benzene-containing coal pyrolysis gas as a reducing agent☆

    Institute of Scientific and Technical Information of China (English)

    Xin Li; Helong Hui; Songgeng Li; Lu He; Lijie Cui

    2016-01-01

    An integrated coal pyrolysis process with iron ore reduction is proposed in this article. As the first step, iron oxide reduction is studied in a fixed bed reactor using simulated coal pyrolysis gas with benzene as a model tar com-pound. Variables such as reduction temperature, reduction time and benzene concentration are studied. The car-bon deposition of benzene results in the retarded iron reduction at low temperatures. At high temperatures over 800 °C, the presence of benzene in the gas can promote iron reduction. The metallization can reach up to 99%in 20 min at 900 °C in the presence of benzene. Significant increases of hydrogen and CO/CO2 ratio are observed in the gas. It is indicated that iron reduction is accompanied by the reforming and decomposition of benzene. The degree of metal ization and reduction increases with the increasing benzene concentration. Iron oxide can nearly completely be converted into cementite with benzene present in the gas under the experimental conditions. No sintering is found in the reduced sample with benzene in the gas.

  5. Mineralogical analysis of auriferous ores from the El Diamante mine, Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Bustos Rodriguez, Humberto, E-mail: hbustos@ut.edu.co; Oyola Lozano, Dagoberto; Rojas Martinez, Yebrayl A. [Universidad del Tolima, Departamento de Fisica (Colombia); Perez Alcazar, German A. [Universidad del Valle, Departamento de Fisica (Colombia); Flege, Stefan; Balogh, Adam G. [Darmstadt University of Technology, Institute of Materials Science (Germany); Cabri, Louis J. [Cabri Consulting Inc. (Canada); Tubrett, Michael [Memorial University of Newfoundland (Canada)

    2007-02-15

    X-ray diffraction (XRD), Moessbauer spectrometry (MS), secondary ions mass spectroscopy (SIMS) and laser-ablation microprobe-inductively coupled plasma-mass spectrometry (LAM-ICP-MS) were used to study mineral samples of Colombian auriferous ores collected from the 'El Diamante' mine, located in the municipality of Guachavez-Narino, in Colombia. The samples were prepared as polished thin sections and polished sections. From XRD data, quartz, sphalerite and pyrite were detected and their respective cell parameters were estimated. From MS analyses, pyrite, arsenopyrite and chalcopyrite were identified; their respective hyperfine parameters and respective texture were deduced. Multiple regions of approximately 200 x 200 {mu}m in each sample were analyzed with SIMS; the occurrence of 'invisible gold' associated mainly with pyrite and secondarily with arsenopyrite could thus be assigned. It was also found that pyrite is of the arsenious type. Spots from 30 to 40 {mu}m in diameter were analyzed with LAM-ICP-MS for pyrite, arsenopyrite and sphalerite; Au is 'homogeneously' distributed inside the structure of the arsenious pyrite and the arsenopyrite (not as inclusions); the chemical composition indicates similarities of this 'invisible gold', forming a solid solution with arsenious pyrite and arsenopyrite. One hundred nineteen and 62 ppm of 'invisible gold' was quantified in 21 spots analyzed on pyrite and in 14 spots on arsenopyrite, respectively.

  6. Fractal analysis of granular ore media based on computed tomography image processing

    Institute of Scientific and Technical Information of China (English)

    WU Ai-xiang; YANG Bao-hua; ZHOU Xu

    2008-01-01

    The cross-sectional images of nine groups of ore samples were obtained by X-ray computed tomography(CT) scanner.Based on CT image analysis,the fractal dimensions of solid matrix,pore space and matrix/pore interface of each sample were measured by using box counting method.The correlation of the three fractal dimensions with particle size,porosity,and seepage coefficient was investigated.The results show that for all images of these samples,the matrix phase has the highest dimension,followed by the pore phase,and the dimension of matrix-pore interface has the smallest value; the dimensions of matrix phase and matrix-pore interface are negatively and linearly correlated with porosity while the dimension of pore phase relates positively and linearly with porosity; the fractal dimension of matrix-pore interface relates negatively and linearly with seepage coefficient.Larger fractal dimension of matrix/pore interface indicates more irregular complicated channels for solution flow,resulting in low permeability.

  7. Mineralogical analysis of auriferous ores from the El Diamante mine, Colombia

    Science.gov (United States)

    Bustos Rodriguez, Humberto; Oyola Lozano, Dagoberto; Rojas Martínez, Yebrayl A.; Pérez Alcázar, Germán A.; Flege, Stefan; Balogh, Adam G.; Cabri, Louis J.; Tubrett, Michael

    2007-02-01

    X-ray diffraction (XRD), Mössbauer spectrometry (MS), secondary ions mass spectroscopy (SIMS) and laser-ablation microprobe-inductively coupled plasma-mass spectrometry (LAM-ICP-MS) were used to study mineral samples of Colombian auriferous ores collected from the “El Diamante” mine, located in the municipality of Guachavez-Nariño, in Colombia. The samples were prepared as polished thin sections and polished sections. From XRD data, quartz, sphalerite and pyrite were detected and their respective cell parameters were estimated. From MS analyses, pyrite, arsenopyrite and chalcopyrite were identified; their respective hyperfine parameters and respective texture were deduced. Multiple regions of approximately 200 × 200 μm in each sample were analyzed with SIMS; the occurrence of “invisible gold” associated mainly with pyrite and secondarily with arsenopyrite could thus be assigned. It was also found that pyrite is of the arsenious type. Spots from 30 to 40 μm in diameter were analyzed with LAM-ICP-MS for pyrite, arsenopyrite and sphalerite; Au is “homogeneously” distributed inside the structure of the arsenious pyrite and the arsenopyrite (not as inclusions); the chemical composition indicates similarities of this “invisible gold”, forming a solid solution with arsenious pyrite and arsenopyrite. One hundred nineteen and 62 ppm of ‘invisible gold’ was quantified in 21 spots analyzed on pyrite and in 14 spots on arsenopyrite, respectively.

  8. Scale up and simulation of Vertimill™ pilot test operated with copper ore

    Directory of Open Access Journals (Sweden)

    Douglas Batista Mazzinghy

    2014-01-01

    Full Text Available Vertimill™ has been used in regrind circuits during the past years due to its greater efficiency when compared to the conventional tube ball mill. This paper presents the Vertimill™ pilot grinding tests with a sample of copper ore carried out in closed circuit with a high frequency screen. The sample was crushed 100% to <6 mm. All operating variables were measured under controlled conditions to produce a mass balance of the test. A laboratory batch ball mill was used to characterize the sample in order to determine the energy specific selection function and the breakage function. Previous studies have shown that the Vertimill™ produces larger values of the selection function and a constant scaling factor can be used to simulate the product particle size distribution of the Vertimill™ from the batch ball mill grinding tests. The results of the simulations showed that it is possible to estimate the product particle size distribution of the Vertimill™ pilot scale from breakage parameters determined from a lab-scale batch ball mill. These results confirm that the Vertimill™ and the conventional ball mill use similar mechanisms of impact and that the main difference between them is the intensity and frequency of the impacts.

  9. Water determination in iron oxyhydroxides and iron ores by Karl Fischer titration

    Science.gov (United States)

    da Cunha, Camila C. R. F.; da Costa, Geraldo M.

    2016-08-01

    Protohematite (Fe2-x/3(OH) x O3-x 1 ≤ x hydroxyl groups in their structures. These species were described in prior studies mainly with the aid of X-ray diffraction and Infrared spectroscopy. The existence of these phases in soils might have influence in redox processes, and they were considered as a possible water reservoir in Martian soils. In this study, we have used for the first time the Karl Fischer titration method to determine the amount of water released after heating several synthetic samples of goethite, hematite and natural iron ores at 105, 400, 600 and 900 °C. It was found that heating at 105 °C did not remove all moisture from the samples, and higher temperatures were necessary to completely remove all the absorbed water. The water contents determined at 400, 600 and 900 °C were found to be the same within the experimental errors, suggesting the inexistence of both protohematite and hydrohematite in the investigated samples. Therefore, the above-mentioned effects of these phases in soils might have to be reevaluated.

  10. AGING PERFORMANCE OF MODEL 9975 PACKAGE FLUOROELASTOMER O-RINGS

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, E.; Daugherty, W.; Skidmore, E.; Dunn, K.; Fisher, D.

    2011-05-31

    The influence of temperature and radiation on Viton{reg_sign} GLT and GLT-S fluoroelastomer O-rings is an ongoing research focus at the Savannah River National Laboratory. The O-rings are credited for leaktight containment in the Model 9975 shipping package used for transportation of plutonium-bearing materials. At the Savannah River Site, the Model 9975 packages are being used for interim storage. Primary research efforts have focused on surveillance of O-rings from actual packages, leak testing of seals at bounding aging conditions and the effect of aging temperature on compression stress relaxation behavior, with the goal of service life prediction for long-term storage conditions. Recently, an additional effort to evaluate the effect of aging temperature on the oxidation of the materials has begun. Degradation in the mechanical properties of elastomers is directly related to the oxidation of the polymer. Sensitive measurements of the oxidation rate can be performed in a more timely manner than waiting for a measurable change in mechanical properties, especially at service temperatures. Measuring the oxidation rate therefore provides a means to validate the assumption that the degradation mechanisms(s) do not change from the elevated temperatures used for accelerated aging and the lower service temperatures. Monitoring the amount of oxygen uptake by the material over time at various temperatures can provide increased confidence in lifetime predictions. Preliminary oxygen consumption analysis of a Viton GLT-based fluoroelastomer compound (Parker V0835-75) using an Oxzilla II differential oxygen analyzer in the temperature range of 40-120 C was performed. Early data suggests oxygen consumption rates may level off within the first 100,000 hours (10-12 years) at 40 C and that sharp changes in the degradation mechanism (stress-relaxation) are not expected over the temperature range examined. This is consistent with the known long-term heat aging resistance of

  11. Formation conditions of high-grade gold-silver ore of epithermal Tikhoe deposit, Russian Northeast

    Science.gov (United States)

    Volkov, A. V.; Kolova, E. E.; Savva, N. E.; Sidorov, A. A.; Prokof'ev, V. Yu.; Ali, A. A.

    2016-09-01

    The Tikhoe epithermal deposit is located in the Okhotsk-Chukotka volcanic belt (OChVB) 250 km northeast of Magadan. Like other deposits belonging to the Ivan'insky volcanic-plutonic depression (VTD), the Tikhoe deposit is characterized by high-grade Au-Ag ore with an average Au grade of 23.13 gpt Au and Au/Ag ratio varying from 1: 1 to 1: 10. The detailed explored Tikhoe-1 orebody is accompanied by a thick (20 m) aureole of argillic alteration. Pyrite is predominant among ore minerals; galena, arsenopyrite, sphalerite, Ag sulfosalts, fahlore, electrum, and küstelite are less abundant. The ore is characterized by abundant Sebearing minerals. Cu-As geochemical specialization is noted for silver minerals. Elevated Se and Fe molar fractions of the main ore minerals are caused by their formation in the near-surface argillic alteration zone. The veins and veinlets of the Tikhoe-1 ore zone formed stepwise at a temperature of 230 to 105°C from Nachloride solution enriched in Mg and Ca cations with increasing salinity. The parameters of the ore-forming fluid correspond to those of epithermal low-sulfidation deposits and assume the formation of high-grade ore under a screening unit of volcanic rocks. In general, the composition of the ore-forming fluid fits the mineralogy and geochemistry of ore at this deposit. The similarity of the ore composition and parameters of the ore-forming fluid between the Tikhoe and Julietta deposits is noteworthy. Meanwhile, differences are mainly related to the lower temperature and fluid salinity at the Julietta deposit with respect to the Tikhoe deposit. The fluid at the Julietta deposit is depleted in most components compared with that at the Tikhoe deposit except for Sb, Cd, and Ag. The results testify to a different erosion level at the deposits as derivatives of the same ore-forming system. The large scale of the latter allows us to predict the discovery of new high-grade objects, including hidden mineralization, which is not exposed at

  12. Spatial data mining system for ore-forming prediction

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The authors designed the spatial data mining system for ore-forming prediction based on the theory and methods of data mining as well as the technique of spatial database, in combination with the characteristics of geological information data. The system consists of data management, data mining and knowledge discovery, knowledge representation. It can syncretize multi-source geosciences data effectively, such as geology,geochemistry, geophysics, RS. The system digitized geological information data as data layer files which consist of the two numerical values, to store these files in the system database. According to the combination of the characters of geological information, metallogenic prognosis was realized, as an example from some area in Heilongjiang Province. The prospect area of hydrothermal copper deposit was determined.

  13. Molybdenum removal from copper ore concentrate by sodium hypochlorite leaching

    Institute of Scientific and Technical Information of China (English)

    Liu Youcai; Zhong Hong; Cao Zhanfang

    2011-01-01

    The removal of molybdenum from a copper ore concentrate by sodium hypochlorite leaching was investigated. The results show that leaching time, liquid to solid ratio, leaching ternperature, agitation speed, and sodium hypochlorite and sodium hydroxide concentrations all have a significant effect on the removal of molybdenum. The optimum process operating parameters were found to be: time, 4 h: sodium hydroxide concentration, 10%; sodium hypochlorite concentration, 8%; liquid to solid ratio, 10:1; temperature, 50℃; and,agitation speed, 500 r/min. Under these conditions the extraction of molybdenum is greater than 99.9% and the extraction of copper is less than 0.01%. A shrinking particle model could be used to describe the leaching process. The apparent activation energy of the dissolution reaction was found to be approximately 8.8 kJ/mol.

  14. Amalgamated Products of Ore and Quadratic Extensions of Rings

    CERN Document Server

    Johnson, Garrett

    2012-01-01

    We study the ideal theory of amalgamated products of Ore and quadratic extensions over a base ring R. We prove an analogue of the Hilbert Basis theorem for an amalgamated product Q of quadratic extensions and determine conditions for when the one-sided ideals of Q are principal or doubly-generated. We also determine conditions that make Q a principal ideal ring. Finally, we show that the double affine Hecke algebra $H_{q,t}$ associated to the general linear group GL_2(k) (here, k is a field with characteristic not 2) is an amalgamated product of quadratic extensions over a three-dimensional quantum torus and give an explicit isomorphism. In this case, it follows that $H_{q,t}$ is a noetherian ring.

  15. Removal of phosphorus from iron ores by chemical leaching

    Institute of Scientific and Technical Information of China (English)

    JIN Yong-shi; JIANG Tao; YANG Yong-bin; LI Qian; LI Guang-hui; GUO Yu-feng

    2006-01-01

    Alkali-leaching and acid-leaching were proposed for the dephosphorization of Changde iron ore, which contains an average of 1.12% for phosphorus content. Sodium hydroxide, sulfuriced, hydrochloric and nitric acids were used for the preparation of leach solutions. The results show that phosphorus occurring as apatite phase could be removed by alkali-leaching, but those occurring in the iron phase could not. Sulfuric acid is the most effective among the three kinds of acid. 91.61% phosphorus removal was attained with 1% sulfuric acid after leaching for 20 min at room temperature. Iron loss during acid-leaching can be negligible, which was less than 0.25%.The pH value of solution after leaching with 1% sulfuric acid was about 0.86, which means acid would not be exhausted during the process and it could be recycled, and the recycle of sulfuric acid solution would make the dephosphorization process more economical.

  16. Oral bioaccessibility of inorganic contaminants in waste dusts generated by laterite Ni ore smelting.

    Science.gov (United States)

    Ettler, Vojtěch; Polák, Ladislav; Mihaljevič, Martin; Ratié, Gildas; Garnier, Jérémie; Quantin, Cécile

    2016-09-14

    The laterite Ni ore smelting operations in Niquelândia and Barro Alto (Goiás State, Brazil) have produced large amounts of fine-grained smelting wastes, which have been stockpiled on dumps and in settling ponds. We investigated granulated slag dusts (n = 5) and fly ash samples (n = 4) with a special focus on their leaching behaviour in deionised water and on the in vitro bioaccessibility in a simulated gastric fluid, to assess the potential exposure risk for humans. Bulk chemical analyses indicated that both wastes contained significant amounts of contaminants: up to 2.6 wt% Ni, 7580 mg/kg Cr, and 508 mg/kg Co. In only one fly ash sample, after 24 h of leaching in deionised water, the concentrations of leached Ni exceeded the limit for hazardous waste according to EU legislation, whereas the other dusts were classified as inert wastes. Bioaccessible fractions (BAF) of the major contaminants (Ni, Co, and Cr) were quite low for the slag dusts and accounted for less than 2 % of total concentrations. In contrast, BAF values were significantly higher for fly ash materials, which reached 13 % for Ni and 19 % for Co. Daily intakes via oral exposure, calculated for an adult (70 kg, dust ingestion rate of 50 mg/day), exceeded neither the tolerable daily intake (TDI) nor the background exposure limits for all of the studied contaminants. Only if a higher ingestion rate is assumed (e.g. 100 mg dust per day for workers in the smelter), the TDI limit for Ni recently defined by European Food Safety Authority (196 µg/day) was exceeded (324 µg/day) for one fly ash sample. Our data indicate that there is only a limited risk to human health related to the ingestion of dust materials generated by laterite Ni ore smelting operations if appropriate safety measures are adopted at the waste disposal sites and within the smelter facility.

  17. The North American iron ore industry: a decade into the 21st century

    Science.gov (United States)

    Jorgenson, John D.; Perez, A. A

    2011-01-01

    During the 20th century, the iron ore mining industries of Canada and the United States passed through periods of transformation. The beginning of the 21st century has seen another period of transformation, with the failure of a number of steel companies and with consolidation of control within the North American iron ore industry. Canadian and United States iron ore production and the market control structure involved are changing rapidly. Consolidation of ownership, formation of foreign joint ventures, divestitures of upstream activities by steelmakers, and industry changes to ensure availability of feedstocks all played a role in recent developments in the North American iron ore industry. Canadian and U.S. iron ore operations and their strong linkage to downstream production, although isolated, must also be considered within the context of the changing global economy. Projects using new technology to produce direct reduced iron nuggets of 96-98% iron content and other projects designed to produce steel at minesites may once again change the face of the iron ore industry. Social and environmental issues related to sustainable development have had a significant effect on the North American iron ore industry.

  18. Culturable microorganisms associated with Sishen iron ore and their potential roles in biobeneficiation.

    Science.gov (United States)

    Adeleke, Rasheed; Cloete, T E; Khasa, D P

    2012-03-01

    With one of the largest iron ore deposits in the world, South Africa is recognised to be among the top ten biggest exporters of iron ore. Increasing demand and consumption of this mineral triggered search for processing technologies, which can be utilised to "purify" the low-grade iron ore minerals that contain high levels of unwanted potassium (K) and phosphorus (P). This study investigated a potential biological method that can be further developed for the full biobeneficiation of low-grade iron ore minerals. Twenty-three bacterial strains that belong to Proteobacteria, Firmicutes, Bacteroidetes and Actinobateria were isolated from the iron ore minerals and identified with sequence homology and phylogenetic methods. The abilities of these isolates to lower the pH of the growth medium and solubilisation of tricalcium phosphate were used to screen them as potential mineral solubilisers. Eight isolates were successfully screened with this method and utilised in shake flask experiments using iron ore minerals as sources of K and P. The shake flask experiments revealed that all eight isolates have potentials to produce organic acids that aided the solubilisation of the iron ore minerals. In addition, all eight isolates produced high concentrations of gluconic acid followed by relatively lower concentrations of acetic, citric and propanoic acid. Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) analyses also indicated extracellular polymeric substances could play a role in mineral solubilisation.

  19. Selective Removal of Iron from Low-Grade Ti Ore by Reacting with Calcium Chloride

    Science.gov (United States)

    Kang, Jungshin; Okabe, Toru H.

    2017-02-01

    Recently, titanium metal production by molten salt electrolysis using CaCl2 as molten salt and TiO2 or rutile (94 to 96 pct TiO2) as feedstock has been drawing attention. However, when a low-grade Ti ore (mainly FeTiO3) is used as feedstock, removal of iron (Fe) from the ore is indispensable. In this study, the influence of reaction temperature, reaction time, particle size of the ore, and source country for the ore on the removal of iron by selective chlorination using CaCl2 was assessed. Experimental results showed that the mass percent of iron in the ore decreased from 49.7 to 1.79 pct under certain conditions by selective removal of iron as FeCl2. As a result, high-grade CaTiO3 was produced when the ore particles smaller than 74 µm reacted with CaCl2 at 1240 K (967 °C) for 8 to 10 hours. Therefore, this study demonstrates that the removal of iron from the ore is feasible through the selective chlorination process using CaCl2 by optimizing the variables.

  20. Strontium isotope geochemistry of the Lemachang independent silver ore deposit, northeastern Yunnan, China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Sr isotope geochemical studies (the 87Sr/86Sr and ?18O-87Sr/86Sr systems) on the wall rocks and ores from the Lemachang independent Ag deposit in northeastern Yunnan provide strong evidence that the ore-forming fluids had flown through radiogenetically Sr-enriched rocks or strata prior to their entry into the locus of ore precipitation, and water-rock interaction is the main mechanism of Ag ore precipitation. The radiogenetically Sr-enriched source region may be the Proterozoic basement (the Kunyang and Hekou groups). Moreover, the theoretical modeling of the Sr isotopic system indicates that the ore-forming fluids contain as much as 3×10?6 Sr with isotopic composition of Sr being 0.750 and that of oxygen 7.0‰. The ore-forming temperatures were estimated at 150-250℃ for the carbonate rock-type ores and at 200-260℃ for the clastic rock-type.

  1. Strontium isotope geochemistry of the Lemachang independent silver ore deposit, northeastern Yunnan, China

    Institute of Scientific and Technical Information of China (English)

    邓海琳; 李朝阳; 涂光炽; 周云满; 王崇武

    2000-01-01

    Sr isotope geochemical studies (the 87Sr/86Sr and δ18O-87Sr/86Sr systems) on the wall rocks and ores from the Lemachang independent Ag deposit in northeastern Yunnan provide strong evidence that the ore-forming fluids had flown through radiogenetically Sr-enriched rocks or strata prior to their entry into the locus of ore precipitation, and water-rock interaction is the main mechanism of Ag ore precipitation. The radiogenetically Sr-enriched source region may be the Proterozoic basement (the Kunyang and Hekou groups). Moreover, the theoretical modeling of the Sr isotopic system indicates that the ore-forming fluids contain as much as 3×10-6 Sr with isotopic composition of Sr being 0.750 and that of oxygen 7.0‰. The ore-forming temperatures were estimated at 150-250℃ for the carbonate rock-type ores and at 200-260℃ for the clastic rock-type.

  2. Selective Removal of Iron from Low-Grade Ti Ore by Reacting with Calcium Chloride

    Science.gov (United States)

    Kang, Jungshin; Okabe, Toru H.

    2016-09-01

    Recently, titanium metal production by molten salt electrolysis using CaCl2 as molten salt and TiO2 or rutile (94 to 96 pct TiO2) as feedstock has been drawing attention. However, when a low-grade Ti ore (mainly FeTiO3) is used as feedstock, removal of iron (Fe) from the ore is indispensable. In this study, the influence of reaction temperature, reaction time, particle size of the ore, and source country for the ore on the removal of iron by selective chlorination using CaCl2 was assessed. Experimental results showed that the mass percent of iron in the ore decreased from 49.7 to 1.79 pct under certain conditions by selective removal of iron as FeCl2. As a result, high-grade CaTiO3 was produced when the ore particles smaller than 74 µm reacted with CaCl2 at 1240 K (967 °C) for 8 to 10 hours. Therefore, this study demonstrates that the removal of iron from the ore is feasible through the selective chlorination process using CaCl2 by optimizing the variables.

  3. A novel stress distribution analytical model of O-ring seals under different properties of materials

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Di; Wang, Shao Ping; Wang, Xing Jian [School of Automation Science and Electrical Engineering, Beihang University, Beijing (China)

    2017-01-15

    The elastomeric O-ring seals have been widely used as sealing elements in hydraulic systems. The sealing performance of O-ring seals is related to stress distribution. The stresses distribution depends on the squeeze rate and internal pressure, and would vary with properties of O-ring seals materials. Thus, in order to study the sealing performance of O-ring seals, it is necessary to describe the analytic relationship between stress distribution and properties of O-ring seals materials. For this purpose, a novel Stress distribution analytical model (SDAM) is proposed in this paper. The analytical model utilizes two stress complex functions to describe the stress distribution of O-ring seals. The proposed SDAM can express not only the analytical relationship between stress distribution and Young’s modulus, but also the one between stress distribution and Poisson’s ratio. Finally, compared results between finite element analysis and the SDAM validate that the proposed model can effectively reveal the stress distribution under different properties for O-ring materials.

  4. Iron-Ore Sintering Process Optimization / Optymalizacja Procesu Aglomeracji Rudy Żelaza

    Directory of Open Access Journals (Sweden)

    Fröhlichová M.

    2015-12-01

    Full Text Available The work deals with examination of the influence of the ratio between iron ore concentrate and iron ore on quality of produced iron ore sinter. One of the possibilities to increase iron content in sinter is the modification of raw materials ratio, when iron ore materials are added into sintering mixture. If the ratio is in favor of iron ore sinter, iron content in resulting sintering mixture will be lower. If the ratio is in favor of iron ore concentrate and recycled materials, which is more finegrained, a proportion of a fraction under 0.5 mm will increase, charge permeability property will be reduced, sintering band performance will decrease and an occurrence of solid particulate matter in product of sintering process will rise. The sintering mixture permeability can be optimized by increase of fuel content in charge or increase of sinter charge moisture. A change in ratio between concentrate and iron ore has been experimentally studied. An influence of sintering mixture grain size composition, a charge grains shape on quality and phase composition on quality of the produced iron sinter has been studied.

  5. SR-XRFA in Biogeochemical Studies: Elemental Composition of Larch Tissues (Larix cajanderi Mayr.) of the Kuranakh Gold ore Field (Russia, Yakutia)

    Science.gov (United States)

    Artamonova, Svetlana Yu.; Zhuravskaya, Alla N.

    Technogenic impact on the elemental composition of larch (Larix cajanderi Mayr.) in the Kuranakh Gold ore field (Russia, Yakutia) is considered. Elemental composition of the larch tissues was determined by means of X-ray fluorescence measurements with synchrotron radiation at the "Siberian Synchrotron and Terahertz Radiation Center" based on VEPP-3 of the Budker Institute of Nuclear Physics SB RAS. Comprehensive possibilities of the X-ray fluorescence measurements along with the simple preparation of biological samples, allowed us to carry out valuable biogeochemical studies. New data on the accumulation of macroelements K, Ca, Mn, Fe, biophilic microelements Cu, Zn, chalcophilous Mo, Pb, Ag, As, Sb, Ga, Cd, Tl, rare lithophilous Rb, Sr, Zr, Y, Nb, in the tissues of larch (Larix cajanderi Mayr.) of the natural taiga landscape and the tailing dump in the Kuranakh Gold ore field were obtained. The results allow us to assess both natural and technogenic biogeochemical anomalous aureole of gold mining areas.

  6. Water quality data at selected sites in the Mississippi Valley-type Zn-Pb ore district of upper Silesia, Poland, 1995-97

    Science.gov (United States)

    Wirt, Laurie; Motyka, Jacek; Leach, David; Sass-Gustkiewicz, Maria; Szuwarzynski, Marek; Adamczyk, Zbigniew; Briggs, Paul; Meiers, Al

    2003-01-01

    The water chemistry of aquifers and streams in the Upper Silesia Ore District, Poland are affected by their proximity to zinc, lead, and silver ores and by ongoing mining activities that date back to the 11th century. This report presents hydrologic and water-quality data collected as part of a collaborative research effort of the U.S. Geological Survey and the University of Mining and Metallurgy in Cracow, Poland to study Mississippi-Valley-Type lead-zinc deposits. MVT deposits in the Upper Silesia Ore District (Fig. 1) were selected for detailed study because the Polish mining industry allowed access to collect samples from underground mines and mine-land property. Water-quality samples were collected from streams, springs, wells, underground mine seeps and drains; and mine-tailings ponds. Data include field measurements of specific conductance, pH, water temperature, and dissolved oxygen and laboratory analyses of major and minor inorganic constituents and selected trace-element constituents.

  7. Dust dispersal and Pb enrichment at the rare-metal Orlovka-Spokoinoe mining and ore processing site: insights from REE patterns and elemental ratios.

    Science.gov (United States)

    Dolgopolova, Alla; Weiss, Dominik J; Seltmann, Reimar; Dulski, Peter

    2006-04-30

    Different geological, technogenic and environmental samples from the Orlovka-Spokoinoe Ta-Nb-Sn-W mining site and ore processing complex in Eastern Transbaikalia (Russia), were analysed for Pb, Y, Zr, Hf and rare earth elements (REE) to assess the effect of dust and metal dispersal on the environment within the Orlovka-Spokoinoe mining site. Potential source material analysed included ore-bearing and barren granites, host rocks, tailing pond sediments, and ore concentrates. Lichens and birch leaves were used as receptor samples. The REE enrichment relative to chondrite, the extent of the Eu anomalies, the enrichments of heavy REE (HREE), and Zr/Hf and Yb/Y ratios suggest that tailings, barren granites, and metasedimentary host rocks are the main sources of dust in the studied mining environment. In addition, calculated lead enrichment (relative to host rocks) suggests that the environment is polluted with Pb. Our results clearly demonstrate the potential of REE patterns and elemental ratios as a reliable technique to trace dust and metals sources and dispersal within a confined mining area offering a new tool for environmental assessment studies.

  8. Dust dispersal and Pb enrichment at the rare-metal Orlovka-Spokoinoe mining and ore processing site: Insights from REE patterns and elemental ratios

    Energy Technology Data Exchange (ETDEWEB)

    Dolgopolova, Alla [Centre for Russian and Central EurAsian Mineral Studies (CERCAMS), Department of Mineralogy, Natural History Museum, Cromwell Road, London SW7 5BD (United Kingdom)]. E-mail: allad@nhm.ac.uk; Weiss, Dominik J. [Centre for Russian and Central EurAsian Mineral Studies (CERCAMS), Department of Mineralogy, Natural History Museum, Cromwell Road, London SW7 5BD (United Kingdom); Department of Earth Science and Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Seltmann, Reimar [Centre for Russian and Central EurAsian Mineral Studies (CERCAMS), Department of Mineralogy, Natural History Museum, Cromwell Road, London SW7 5BD (United Kingdom); Dulski, Peter [GFZ Potsdam, Telegrafenberg, D-14473 Potsdam (Germany)

    2006-04-30

    Different geological, technogenic and environmental samples from the Orlovka-Spokoinoe Ta-Nb-Sn-W mining site and ore processing complex in Eastern Transbaikalia (Russia), were analysed for Pb, Y, Zr, Hf and rare earth elements (REE) to assess the effect of dust and metal dispersal on the environment within the Orlovka-Spokoinoe mining site. Potential source material analysed included ore-bearing and barren granites, host rocks, tailing pond sediments, and ore concentrates. Lichens and birch leaves were used as receptor samples. The REE enrichment relative to chondrite, the extent of the Eu anomalies, the enrichments of heavy REE (HREE), and Zr/Hf and Yb/Y ratios suggest that tailings, barren granites, and metasedimentary host rocks are the main sources of dust in the studied mining environment. In addition, calculated lead enrichment (relative to host rocks) suggests that the environment is polluted with Pb. Our results clearly demonstrate the potential of REE patterns and elemental ratios as a reliable technique to trace dust and metals sources and dispersal within a confined mining area offering a new tool for environmental assessment studies.

  9. Application of 57Fe Mössbauer spectroscopy as a tool for mining exploration of bornite (Cu5FeS4) copper ore

    Science.gov (United States)

    Gainov, R. R.; Vagizov, F. G.; Golovanevskiy, V. A.; Ksenofontov, V. A.; Klingelhöfer, G.; Klekovkina, V. V.; Shumilova, T. G.; Pen'kov, I. N.

    2014-04-01

    Nuclear resonance methods, including Mössbauer spectroscopy,are considered as unique techniques suitable for remote on-line mineralogical analysis. The employment of these methods provides potentially significant commercial benefits for mining industry. As applied to copper sulfide ores, Mössbauer spectroscopy method is suitable for the analysis noted. Bornite (formally Cu5FeS4) is a significant part of copper ore and identification of its properties is important for economic exploitation of commercial copper ore deposits. A series of natural bornite samples was studied by 57Fe Mössbauer spectroscopy. Two aspects were considered: reexamination of 57Fe Mössbauer properties of natural bornite samples and their stability irrespective of origin and potential use of miniaturized Mössbauer spectrometers MIMOS II for in-situ bornite identification. The results obtained show a number of potential benefits of introducing the available portative Mössbauer equipment into the mining industry for express mineralogical analysis. In addition, results of some preliminary 63,65Cu nuclear quadrupole resonance (NQR) studies of bornite are reported and their merits with Mössbauer techniques for bornite detection discussed.

  10. Numerical Modelling of Ore-forming Dynamics of Fractal Dispersive Fluid Systems

    Institute of Scientific and Technical Information of China (English)

    邓军; 方云; 杨立强; 杨军臣; 孙忠实; 王建平; 丁式江; 王庆飞

    2001-01-01

    Based on an analysis of the fractal structures and mass transport mechanism of typical shear-fluid-ore formation system, the fractal dispersion theory of the fluid system was used in the dynamic study of the ore formation system. The model of point-source diffusive illuviation of the shear-fluid-ore formation system was constructed, and the numerical simulation of dynamics of the ore formation system was finished. The result shows that: (1) The metallogenic system have nested fractal structure. Different fractal dimension values in different systems show unbalance and inhomogeneity of ore-forming processes in the geohistory. It is an important parameter to symbolize the process of remobilization and accumulation of ore-forming materials. Also it can indicate the dynamics of the metallogenic system quantitatively to some extent. (2) In essence, the fractal dispersive ore-forming dynamics is a combination of multi-processes dominated by fluid dynamics and supplemented by molecule dispersion in fluids and fluid-rock interaction. It changes components and physico-chemical properties of primary rocks and fluids, favouring deposition and mineralization of ore-forming materials. (3) Gold ore-forming processes in different types of shear zones are quite different. (1) In a metallogenic system with inhomogeneous volumetric change and inhomogeneous shear, mineralization occurs in structural barriers in the centre of a shear zone and in geochemical barriers in the shear zone near its boundaries. But there is little possibility of mineralization out of the shear zone. (2) As to a metallogenic system with inhomogeneous volumetric change and simple shear, mineralization may occur only in structural barriers near the centre of the shear zone. (3) In a metallogenic system with homogeneous volumetric change and inhomogeneous shear, mineralization may occur in geochemical barriers both within and out of the shear zone.

  11. ON SOME KEY GEOLOGICAL PROBLEMS RELATED TO THE LINGLONG-JIAOJIA ORE-CENTRALIZED DISTRICT IN SHANDONG PROVINCE, CHINA

    Institute of Scientific and Technical Information of China (English)

    WANG Jincao; XIA Bin; TANG Jingru

    2003-01-01

    The Lingtong-Jiaojia ore-centralized district is controlled by the tectonic stress field characterized bY the combination of extension and strike-slip, and the dip, dip angle, pitch and pitch angle of the ore bodies are all constrained by the dynamic conditions of the tectonics. The metallotectonic series for the ore-centralized district belong to the type of a combination of extension and strike-slip and can be subdivided into four sub-series. The ore-forming process in the brittle regime can be disintegrated into two stages, i.e., the embryonic fracture stage and the megascopic fracture stage, and ore-forming process is rather common in the ore-centralized district at the former stage. Moreover, several key structural patterns and their features were discussed and a preliminary assessment about the ore-forming prospect in this district was made in the paper.

  12. A study on iron ore transportation model with penalty value of transportation equipment waiting

    Directory of Open Access Journals (Sweden)

    Kailing Pan

    2017-03-01

    Full Text Available As some steel enterprises are at a disadvantage in the choice of the mode of transportation, this paper made further studies of the characteristics of the iron ore logistics, taking comprehensive consideration of optimizing the waiting time under the conditions with limited loading capacity and setting up a procedural model of the iron ore logistics system with minimum cost of transportation, storage, loading, unloading, and transportation equipment waiting. Finally, taking the iron ore transport system of one steel enterprise as example, the solution and the validity of the model were analyzed and verified in this paper.

  13. Da identidade açoriana ao consumo da marca Açores

    OpenAIRE

    Negalha, Raquel Raposo

    2015-01-01

    Dissertação de Mestrado, Sociologia, 24 de Setembro de 2015, Universidade dos Açores. O presente Projeto de Dissertação insere-se na área da sociologia do consumo intitulada Da Identidade Açoriana ao Consumo da Marca Açores. A pertinência da mesma prende-se com o facto de o Projeto “Marca Açores” desenvolvido pela Sociedade para o Desenvolvimento dos Açores (SDEA) ser uma novidade para as empresas que se encontram interessadas em incutir o selo da mesma nos seus produtos de modo a que este...

  14. Application of LANDSAT satellite imagery for iron ore prospecting in the Western Desert of Egypt

    Science.gov (United States)

    Elshazly, E. M.; Abdelhady, M. A.; Elghawaby, M. A.; Khawasik, S. M.

    1977-01-01

    Prospecting for iron ore occurrences was conducted by the Remote Sensing Center in Bahariya Oasis-El Faiyum area covering some 100,000 km squared in the Western Desert of Egypt. LANDSAT-1 satellite images were utilized as the main tool in the regional prospecting of the iron ores. The delineation of the geological units and geological structure through the interpretation of the images corroborated by field observations and structural analysis led to the discovery of new iron ore occurrences in the area of investigation.

  15. Innovative application of mathematical methods in evaluation of ore raw materials for production of iron

    Directory of Open Access Journals (Sweden)

    P. Besta

    2014-01-01

    Full Text Available Current principles of evaluation of ore raw materials are usually based on a comparison of selected isolated criteria. Today‘s sophisticated technological level of blast furnace process requires the introduction of raw material indicators that provide global characteristics of their quality. This can´t be realized with isolated parameters only. The evaluation should incorporate the key characteristics of iron ore and convert them into a uniform evaluation parameter. This article analyzes the use of mathematical methods in the evaluation of the quality of ore raw materials.

  16. TWO-DIMENSIONAL AXISYMMETRIC MODELING OF COMBUSTION IN AN IRON ORE SINTERING BED

    DEFF Research Database (Denmark)

    Lafmejani, Saeed Sadeghi; Davazdah Emami, Mohsen; Panjehpour, Masoud;

    2013-01-01

    A twodimensional model, based on conservation of mass, momentum and energy equations, is represented in this paper in which the coke combustion process, for iron ore sintering in a packed bed, is simulated numerically. The aforementioned packed bed consists of iron ore, coke, limestone and moisture...... of species are solved numerically by using a computational fluid dynamics code in a discrete solving domain. Modeling of iron ore sintering has complex and various features like coke combustion, complicated physical changes of solid phase particles and different modes of heat transfer, for example convection...

  17. Manufacturing and Application of Metalized Ore-Coal Pellets in Synthetic Pig Iron Smelting

    Science.gov (United States)

    Nokhrina, O. I.; Rozhikhina, I. D.; Khodosov, I. E.

    2016-08-01

    The article presents research data on manufacturing and application of metalized ore-coal pellets in synthetic pig iron smelting. A technology of pellets metallization by means of solid-phase reduction of iron from oxides using hematite-magnetite iron ore and low-caking coal as raw materials is described. Industrial testing of replacing 10, 15, and 20% of waste metal by the metalized ore-coal pellets in the coreless induction furnace IST-1 is described. Optimal temperature and time conditions of feeding the metalized pellets into the furnace in smelting pig iron of SCh-40-60 grade are determined.

  18. Evaluation of the treatment of chromite ore processing residue by ferrous sulfate and asphalt.

    Science.gov (United States)

    Moon, Deok Hyun; Wazne, Mahmoud; Koutsospyros, Agamemnon; Christodoulatos, Christos; Gevgilili, Halil; Malik, Moinuddin; Kalyon, Dilhan M

    2009-07-15

    The effectiveness of the treatment of chromite ore processing residue (COPR) with ferrous sulfate and encapsulation into asphalt were explored separately and in combination. The asphalt treatment was conducted by mixing COPR or ferrous sulfate pretreated COPR with varying amounts of asphalt. To assess the efficacy of the treatment, the leachability of toxicity characteristic leaching procedure (TCLP) total chromium (Cr) from all treated samples was determined for curing periods up to 16 months. X-ray absorption near edge structure (XANES) analyses were also performed to evaluate the Cr(6+) concentration in the selected samples. The combination treatment of ferrous sulfate and the encapsulation of the treated COPR into asphalt reduced the TCLP total Cr concentration to lower than the regulatory limit of 5mg/L for Cr contaminated soils, after 16 months. However, the Cr concentrations were still higher than the universal treatment standards (UTS) of 0.6 mg/L for hazardous waste. On the other hand, treatment with ferrous sulfate alone or the encapsulation of the COPR in asphalt failed to meet the TCLP total Cr concentration of 5mg/L, after 16 months. XANES analyses results showed that more than 75% Cr(6+) reduction was achieved upon pretreatment with ferrous sulfate.

  19. Kinetic studies on the reduction of iron ore nuggets by devolatilization of lean-grade coal

    Science.gov (United States)

    Biswas, Chanchal; Gupta, Prithviraj; De, Arnab; Chaudhuri, Mahua Ghosh; Dey, Rajib

    2016-12-01

    An isothermal kinetic study of a novel technique for reducing agglomerated iron ore by volatiles released by pyrolysis of lean-grade non-coking coal was carried out at temperature from 1050 to 1200°C for 10-120 min. The reduced samples were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and chemical analysis. A good degree of metallization and reduction was achieved. Gas diffusion through the solid was identified as the reaction-rate-controlling resistance; however, during the initial period, particularly at lower temperatures, resistance to interfacial chemical reaction was also significant, though not dominant. The apparent rate constant was observed to increase marginally with decreasing size of the particles constituting the nuggets. The apparent activation energy of reduction was estimated to be in the range from 49.640 to 51.220 kJ/mol and was not observed to be affected by the particle size. The sulfur and carbon contents in the reduced samples were also determined.

  20. Kinetic studies on the reduction of iron ore nuggets by devolatilization of lean-grade coal

    Institute of Scientific and Technical Information of China (English)

    Chanchal Biswas; PrithviraJGupta; Arnab De; Mahua Ghosh Chaudhuri; and Rajib Dey

    2016-01-01

    An isothermal kinetic study of a novel technique for reducing agglomerated iron ore by volatiles released by pyrolysis of lean-grade non-coking coal was carried out at temperature from 1050 to 1200°C for 10–120 min. The reduced samples were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and chemical analysis. A good degree of metallization and reduction was achieved. Gas diffusion through the solid was identified as the reaction-rate-controlling resistance; however, during the initial period, particularly at lower temperatures, resistance to interfacial chemical reaction was also significant, though not dominant. The apparent rate constant was observed to increase marginally with decreasing size of the particles constituting the nuggets. The apparent activation energy of reduction was estimated to be in the range from 49.640 to 51.220 kJ/mol and was not observed to be affected by the particle size. The sulfur and carbon contents in the reduced samples were also determined.

  1. FY2017 status report: Model 9975 O-ring fixture long-term leak performance

    Energy Technology Data Exchange (ETDEWEB)

    Daugherty, W. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-07-27

    A series of experiments to monitor the aging performance of Viton® GLT and GLT-S O-rings used in the Model 9975 shipping package has been ongoing since 2004 at the Savannah River National Laboratory. One approach has been to periodically evaluate the leak performance of O-rings being aged in mock-up 9975 Primary Containment Vessels (PCVs) at elevated temperature. Other methods such as compression-stress relaxation (CSR) tests and field surveillance are also on-going to evaluate O-ring behavior. Seventy tests using PCV mock-ups with GLT O-rings were assembled and heated to temperatures ranging from 200 to 450 ºF. They were leak-tested initially and have been tested periodically to determine if they continue to meet the leak-tightness criterion defined in ANSI standard N14.5-97. Due to material substitution, a smaller test matrix with fourteen additional tests was initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 ºF. Leak test failures have been experienced in all of the GLT O-ring fixtures aging at 350 ºF and higher temperatures, and in 8 fixtures aging at 300 ºF. The 300 °F GLT O-ring fixtures failed after 2.8 to 5.7 years at temperature. The remaining GLT O-ring fixtures aging at 300 ºF were retired from testing following more than 5 years at temperature without failure. No failures have yet been observed in GLT O-ring fixtures aging at 200 ºF for 9 to 10.5 years, or in GLT O-ring fixtures aging at 270 ºF for 5.7 years. These aging temperatures bound O-ring temperatures anticipated during normal storage in K-Area Complex (KAC). Leak test failures have been experienced in all of the GLT-S O-ring fixtures aging at 300 ºF and above. No failures have yet been observed in GLT-S O-ring fixtures aging at 200 and 250 ºF for 6.9 to 7.5 years. Data from the O-ring fixtures are generally consistent with results from compression stress relaxation testing, and provide confidence in the predictive models based on those results

  2. The search for asbestos within the Peter Mitchell Taconite iron ore mine, near Babbitt, Minnesota.

    Science.gov (United States)

    Ross, Malcolm; Nolan, Robert P; Nord, Gordon L

    2008-10-01

    Asbestos crystallizes within rock formations undergoing intense deformation characterized by folding, faulting, shearing, and dilation. Some of these conditions have prevailed during formation of the taconite iron ore deposits in the eastern Mesabi Iron Range of Minnesota. This range includes the Peter Mitchell Taconite Mine at Babbitt, Minnesota. The mine pit is over 8 miles long, up to 1 mile wide. Fifty three samples were collected from 30 sites within areas of the pit where faulting, shearing and folding occur and where fibrous minerals might occur. Eight samples from seven collecting sites contain significant amounts of ferroactinolite amphibole that is partially to completely altered to fibrous ferroactinolite. Two samples from two other sites contain ferroactinolite degraded to ropy masses of fibers consisting mostly of ferrian sepiolite as defined by X-ray diffraction and TEM and SEM X-ray spectral analysis. Samples from five other sites contain unaltered amphiboles, however some of these samples also contain a very small number of fiber bundles composed of mixtures of grunerite, ferroactinolite, and ferrian sepiolite. It is proposed that the alteration of the amphiboles was caused by reaction with water-rich acidic fluids that moved through the mine faults and shear zones. The fibrous amphiboles and ferrian sepiolite collected at the Peter Mitchell Mine composes a tiny fraction of one percent of the total rock mass of this taconite deposit; an even a smaller amount of these mineral fragments enter the ambient air during mining and milling. These fibrous minerals thus do not present a significant health hazard to the miners nor to those non-occupationally exposed. No asbestos of any type was found in the mine pit.

  3. Lead-isotopic, sulphur-isotopic, and trace-element studies of galena from the Silesian-Cracow Zn-Pb ores, polymetallic veins from the Gory Swietokrzyskie MTS, and the Myszkow porphyry copper deposit, Poland

    Science.gov (United States)

    Church, S.E.; Vaughn, R.B.; Gent, C.A.; Hopkins, R.T.

    1996-01-01

    Lead-isotopic data on galena samples collected from a paragenetically constrained suite of samples from the Silesian-Cracow ore district show no regional or paragenetically controlled lead-isotopic trends within the analytical reproducibility of the measurements. Furthermore, the new lead-isotopic data agree with previously reported lead-isotopic results (R. E. Zartman et al., 1979). Sulfur-isotopic analyses of ores from the Silesian-Cracow district as well as from vein ore from the Gory Swietokrzyskie Mts. and the Myszkow porphyry copper deposit, when coupled with trace-element data from the galena samples, clearly discriminate different hydrothermal ore-forming events. Lead-isotopic data from the Permian and Miocene evaporite deposits in Poland indicate that neither of these evaporite deposits were a source of metals for the Silesian-Cracow district ores. Furthermore, lead-isotopic data from these evaporite deposits and the shale residues from the Miocene halite samples indicate that the crustal evolution of lead in the central and western European platform in southern Poland followed normal crustal lead-isotopic growth, and that the isotopic composition of crustal lead had progressed beyond the lead-isotopic composition of lead in the Silesian-Cracow ores by Permian time. Thus, Mesozoic and Tertiary sedimentary flysch rocks can be eliminated as viable source rocks for the metals in the Silesian-Cracow Mississippi Valley-type (MVT) deposits. The uniformity of the isotopic composition of lead in the Silesian-Cracow ores, when coupled with the geologic evidence that mineralization must post-date Late Jurassic faulting (E. Gorecka, 1991), constrains the geochemical nature of the source region. The source of the metals is probably a well-mixed, multi-cycle molasse sequence of sedimentary rocks that contains little if any Precambrian metamorphic or granitic clasts (S. E. Church, R. B. Vaughn, 1992). If ore deposition was post Late Jurassic (about 150 m. y.) or later

  4. Environmental status of groundwater affected by chromite ore processing residue (COPR) dumpsites during pre-monsoon and monsoon seasons.

    Science.gov (United States)

    Matern, Katrin; Weigand, Harald; Singh, Abhas; Mansfeldt, Tim

    2017-02-01

    Chromite ore processing residue (COPR) is generated by the roasting of chromite ores for the extraction of chromium. Leaching of carcinogenic hexavalent chromium (Cr(VI)) from COPR dumpsites and contamination of groundwater is a key environmental risk. The objective of the study was to evaluate Cr(VI) contamination in groundwater in the vicinity of three COPR disposal sites in Uttar Pradesh, India, in the pre-monsoon and monsoon seasons. Groundwater samples (n = 57 pre-monsoon, n = 70 monsoon) were taken in 2014 and analyzed for Cr(VI) and relevant hydrochemical parameters. The site-specific ranges of Cr(VI) concentrations in groundwater were <0.005 to 34.8 mg L(-1) (Rania), <0.005 to 115 mg L(-1) (Chhiwali), and <0.005 to 2.0 mg L(-1) (Godhrauli). Maximum levels of Cr(VI) were found close to the COPR dumpsites and significantly exceeded safe drinking water limits (0.05 mg L(-1)). No significant dependence of Cr(VI) concentration on monsoons was observed.

  5. New data on age of ore-hosting sequence of the Saf'yanovka deposit, Central Urals, based on foraminifers

    Science.gov (United States)

    Chuvashov, B. I.; Anfimov, A. L.; Soroka, E. I.; Yaroslavtseva, N. S.

    2011-08-01

    The Saf'yanovka copper massive sulfide deposit is situated 10 km northeast from the town of Rezh, on the eastern slope of the Central Urals. The ore-hosting plagiorhyolite-dacitic sequence consists of tephrites and tuffites with interlayers of dark gray siliceous-carboniferous pelites and psephytes from 0.1 to 1.5 m thick. The shells of the Parathurammina tamarae L. Petrovae, 1981 foraminifer were identified in one of the lightened interlayers in the siliceous-carboniferous sequence. The samples for study were taken from the southern part of the orebody in the open-pit between prospecting lines 2 and 3, horizons 170 and 157. The inner part of the shell is composed of quartz and apatite, and the wall, by apatite with rare calcite grains. One shell contains a tacking disk allowing us to refer these foraminifers to the attached benthos typical of the shallow marine basin (sublitoral). In the Urals, the Parathurammina tamarae L. Petrovae, 1981 foraminifer is known in limestones from the Eifel-Givetian (Langurskii and Vysotinskii Horizons); the siliceous-carboniferous rocks from the ore-hosting sequence from the Saf'yanovka deposit has the same age.

  6. Beneficiation of Iraqi Akash at Phosphate Ore Using Organic Acids for the Production of Wet Process Phosphoric Acid

    Directory of Open Access Journals (Sweden)

    Mohammed Y. Eisa

    2013-12-01

    Full Text Available In the present work, leaching process studiedusing organic acids (acetic acid and lactic acid to extract phosphate from the Iraqi Akashat phosphate ore by separation of calcareous materials (mainly calcite. This approach characterized by energy conservation, environmental enhancement by recovery of calcite as calcium sulfate (gypsum, keeping the physical and chemical properties of apatite. Samples were analyzed using X-ray diffraction and FTIR spectrophotometer. From the obtained experimental data it was found that using the two organic acids yields closed purity values of the produced apatite at the optimum conditions, while at different acid concentrations, it was found that the efficiency of acetic acid is higher at the low acid concentration (2 wt%, and that lactic acid gives the higher efficiency at high acid concentration (10 wt%.Concerning the ratio of acid volume to ore weight ratio, it was found that reducing this ratio to 5 ml/gm cause an increase in the purity of apatite at the optimum concentrations of the two acids. In addition, it was found that the reaction ofthe two organic acids with the calcareous material are fast and that the optimum reaction time, in which high purity apatite produced is 10 minutes.

  7. Ore genesis constraints on the Idaho Cobalt Belt from fluid inclusion gas, noble gas isotope, and ion ratio analyses

    Science.gov (United States)

    Hofstra, Albert H.; Landis, Gary P.

    2012-01-01

    The Idaho cobalt belt is a 60-km-long alignment of deposits composed of cobaltite, Co pyrite, chalcopyrite, and gold with anomalous Nb, Y, Be, and rare-earth elements (REEs) in a quartz-biotite-tourmaline gangue hosted in Mesoproterozoic metasedimentary rocks of the Lemhi Group. It is the largest cobalt resource in the United States with historic production from the Blackbird Mine. All of the deposits were deformed and metamorphosed to upper greenschist-lower amphibolite grade in the Cretaceous. They occur near a 1377 Ma anorogenic bimodal plutonic complex. The enhanced solubility of Fe, Co, Cu, and Au as chloride complexes together with gangue biotite rich in Fe and Cl and gangue quartz containing hypersaline inclusions allows that hot saline fluids were involved. The isotopes of B in gangue tourmaline are suggestive of a marine source, whereas those of Pb in ore suggest a U ± Th-enriched source. The ore and gangue minerals in this belt may have trapped components in fluid inclusions that are distinct from those in post-ore minerals and metamorphic minerals. Such components can potentially be identified and distinguished by their relative abundances in contrasting samples. Therefore, we obtained samples of Co and Cu sulfides, gangue quartz, biotite, and tourmaline and post-ore quartz veins as well as Cretaceous metamorphic garnet and determined the gas, noble gas isotope, and ion ratios of fluid inclusion extracts by mass spectrometry and ion chromatography. The most abundant gases present in extracts from each sample type are biased toward the gas-rich population of inclusions trapped during maximum burial and metamorphism. All have CO2/CH4 and N2/Ar ratios of evolved crustal fluids, and many yield a range of H2-CH4-CO2-H2S equilibration temperatures consistent with the metamorphic grade. Cretaceous garnet and post-ore minerals have high RH and RS values suggestive of reduced sulfidic conditions. Most extracts have anomalous 4He produced by decay of U and Th and

  8. Gold grade of epithermal gold ore at Lamuntet, Brang Rea, West Sumbawa District, West Nusa Tenggara Province, Indonesia

    Science.gov (United States)

    Ernawati, Rika; Idrus, Arifudin; TBMP, Himawan

    2017-06-01

    Lamuntet is one of gold ore mining area carried out by the Artisanal Small scale Gold Mining (ASGM) located in West Sumbawa, Indonesia. Most of the miners at this area are not the local miners but also those from other regions. Mineralization of this area is strong identified as low sulfidation epithermal system. There are two blocks of this mining location, namely, Ngelampar block with an area of 0.164 km2 and Song block with an area of 0.067 km2. This study was focused on Ngelampar block. The characteristic of epithermal system is the existence of quartz vein with comb, vuggy, and sugary texture. The aim of this research was to analyze the gold grade and other metals, such as Cu, Ag, Pb, As, Zn, and Hg. The research methods included literature study from previous researches, field work, laboratory work, and interpretation. The literature study was performed on previous researches with similar study area. The field work comprised of direct observation and sampling. Fieldwork was done for a week to obtain gold ore/vein. Sixteen samples were analyzed to obtain the grade of ore/metal. The Hg laboratory analysis was then performed on the six samples with the highest gold grade. Laboratory works were conducted at Intertek Jakarta by using Fire Assay (FA) for gold grade and Atomic Absorption Spectrophotometry (AAS) for Cu, Ag, Pb, As, Zn, and Hg. Results of the analysis showed the range of Au was grade (0.1 ppm - 27.8 ppm), Cu was 26 ppm -1740 ppm, Pb was 101 ppm- >4000 ppm, Zn of 73 ppm- >10,000 ppm, Ag of 3 ppm -185 ppm, As was 150 ppm-6530 ppm, and Hg of 0.08 ppm - 1.89 ppm. L1 and L15 had high grade for all values (Au, Ag, Zn, Cu, As, and Hg). Gold mineralization was formed as electrum because of Ag content is higher than 20%. Associated minerals of the samples in the study area were galena, sphalerite, arsenopyrite, and chalcopyrite which showed the characteristic of rich base metal of Pb, Zn, and Cu at LS epithermal.

  9. Temporal and spatial distribution of Au-Ag polymetallic ore deposits and source of ore-forming materials in the Zhangjiakou-Xuanhua mantle-branch metallogenetic zone

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Zhangjiakou-Xuanhua area is a mineral resource-concentrated area for gold-silver polymetallic ore deposits. The temporal and spatial distribution and origin of mineral resources have been argued for a long time. Based on the comprehensive studies of geochronology and sulfur, lead, oxygen, carbon and noble gas isotopes, it is considered that the temporal and spatial distribution of mineral resources in this area is obviously controlled by the Zhangjiakou-Xuanhua mantle branch structure, as is reflected by the occurrence of gold deposits in the inner parts and of Ag-Pb-Zn polymetallic ore deposits in the outer parts. The mineralization took place mainly during the Yanshanian period. Ore-forming materials came largely from the deep interior of the Earth, and hydrothermal fluids were derived predominantly from Yanshanian magmatism.

  10. Pump-lockage ore transportation system for deep sea flexible mining system

    Institute of Scientific and Technical Information of China (English)

    XU Hai-liang; YIN Ping-wei; XU Shao-jun; YANG Fang-qiong

    2008-01-01

    Based on characteristics of deep sea flexible mining system, a new pump-lockage ore transportation system was designed. According to Bernoulli equation and two-phase hydrodynamics theory, parameters of the new system were obtained and four ore transportation systems were analyzed. The results indicate that the pump head of 1000 m mining system is 100-150 m and that of 5 000 m mining system is 660-750 m. In addition, based on similarity theory, a model of the new transportation system was made,which can simulate more than 5 000 m actual ore transportation system. So both theory and experiment prove that the new pump-lockage ore transportation system is an ideal design for deep sea flexible mining system.

  11. The study of volume ultrasonic waves propagation in the gas-containing iron ore pulp.

    Science.gov (United States)

    Morkun, V; Morkun, N; Pikilnyak, A

    2015-02-01

    The results of research of the volume ultrasonic waves propagation in the gas-containing iron ore slurry using ultrasonic phased array technology is presented. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Liberation of Oolitic Hematite Grains From Iron Ore,Dilband Mines Pakistan

    Directory of Open Access Journals (Sweden)

    Muhammad Ishaque Abro

    2011-04-01

    Full Text Available Dilband Mine is one of the main iron ore deposits of Balochistan Pakistan, containing about 200milion tones of ore. The Dilband iron ore is mainly composed of oolitic-hematite along with the quartz, calcite, fluorapatite, kaolin, and chlinochlore gangue minerals. The basic objective of the paper is to report the operating conditions of comminuting step where maximum liberation of oolitic hematite from the matrix enriched with calcite and fluorapatite minerals has been possible. Besides this quantitative and qualitative analysis of particles based on concentrate, middlings, and tailings susceptibility of particles is proposed. Comminution circuit for Dilband iron ore is designed on the basis of work index, grade and percent distribution of oolitic-hematite particles in concentrate, middlings and tailings.

  13. SEVENTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE

    Energy Technology Data Exchange (ETDEWEB)

    Daugherty, W.

    2012-08-30

    A series of experiments to monitor the aging performance of Viton® GLT O-rings used in the Model 9975 package has been ongoing since 2004 at the Savannah River National Laboratory. Seventy tests using mock-ups of 9975 Primary Containment Vessels (PCVs) were assembled and heated to temperatures ranging from 200 to 450 ºF. They were leak-tested initially and have been tested periodically to determine if they meet the criterion of leak-tightness defined in ANSI standard N14.5-97. Fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 ºF. High temperature aging continues for 23 GLT O-ring fixtures at 200 – 270 ºF. Room temperature leak test failures have been experienced in all of the GLT O-ring fixtures aging at 350 ºF and higher temperatures, and in 8 fixtures aging at 300 ºF. The remaining GLT O-ring fixtures aging at 300 ºF have been retired from testing following more than 5 years at temperature without failure. No failures have yet been observed in GLT O-ring fixtures aging at 200 ºF for 54-72 months, which is still bounding to O-ring temperatures during storage in K-Area Complex (KAC). Based on expectations that the fixtures aging at 200 ºF will remain leak-tight for a significant period yet to come, 2 additional fixtures began aging in 2011 at an intermediate temperature of 270 ºF, with hopes that they may reach a failure condition before the 200 ºF fixtures. High temperature aging continues for 6 GLT-S O-ring fixtures at 200 – 300 ºF. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring fixtures aging at 350 and 400 ºF. No failures have yet been observed in GLT-S O-ring fixtures aging at 200 - 300 ºF for 30 - 36 months. For O-ring fixtures that have failed the room temperature leak test and been disassembled, the O-rings displayed a compression set ranging from 51 – 96%. This is greater than seen to date for any packages inspected during KAC field

  14. 76 FR 9449 - National Emission Standards for Hazardous Air Pollutants: Gold Mine Ore Processing and Production...

    Science.gov (United States)

    2011-02-17

    ... add carbon adsorbers to control the ore pre-heaters. Based on this beyond-the-floor analysis, we... controls on all thermal units at Nevada gold mines. According to the commenters, these permits are...

  15. Experimental Study on the Properties of Concrete Mixed with Iron Ore Tailings

    National Research Council Canada - National Science Library

    Tian, Zhong-xi; Zhao, Zeng-hui; Dai, Chun-quan; Liu, Shu-jie

    2016-01-01

    .... Firstly, the raw materials of mixing were analyzed, and the test ratio was determined. Secondly, the workability and mechanical property of concrete specimens with different amounts of iron ore tailings as replacement were tested...

  16. The applications of microwave energy to improve grindability and extraction of gold ores

    CERN Document Server

    Huang, J H

    2000-01-01

    decomposed than pyrite at the same exposure conditions. Scanning electron microscope (SEM), optical microscope, and X-ray diffraction results indicated that the alterations during microwave treatment were complex. Some intermediate products (e.g. Fe sub ( sub 1 sub - sub x sub ) S) were formed before the sulphides were completely oxidised into hematite (Fe sub 2 O sub 3). Oxidation developed from the surfaces into the cores of the microwaved particles. Metallic particles were also formed during microwave exposure. Lihir gold ore, in which gold was finely disseminated in pyrite and marcasite, was an extremely refractory gold ore. Without pretreatment, only 37 approx 39% of the gold could be extracted with sodium cyanide. However, this was improved after the head ores or floatation concentrates were pretreated by microwave radiation. 74.5 approx 81.2% of the gold was extracted from the microwave treated head ore. The hydrometallurgical pretreatment of pyrite and marcasite in a microwave field and a conventional...

  17. SUSTAINABILITY IN PELLETIZING IRON ORE THROUGH THE INDUSTRIAL ECOLOGY AND CLEANER PRODUCTION PROGRAM

    National Research Council Canada - National Science Library

    Cristiano Farias Coelho; Gudelia Morales

    2013-01-01

      This study aims to analyze the practices of a pelletizing iron ore industry with respect to adoption of pollution prevention measures, suggested by applying the concepts of Cleaner Production and Material Flow Analysis...

  18. Tectonic ore-controlling in the middle southern segment of Da Hinggan Ling, Northeast China

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Studies on geotectonic evolution, regionally geological characteristics and ore-forming and ore-controlling structures have shown that since the Mesozoic the Da Hinggan Ling region has entered the typical intercontinental orogenic stage, which appears to be closely related to mantle plume activities. Da Hinggan Ling is a typical mantle branch structure and possesses obvious magmatic-metamorphic complexes in the core, detachment slip beds in the periphery and overlapped fault depression basins. Moreover, all these are the principal factors leading to ore formation and ore controlling in the region. This paper also further explores the mechanism of mineralization in the middle-southern segment of Da Hinggan Ling,summaries the rules of mineralization, puts forward the models of mineralization and points out the oresearch orientations in the future time.

  19. The implementation and evaluation of a behaviour-based safety intervention at an iron ore mine

    National Research Council Canada - National Science Library

    GP Möller; Sebastiaan Rothmann

    2014-01-01

    .... The aim of this study was to determine to what extent the safety culture and safety performance in an iron ore mine were affected by the implementation of a behaviour-based safety intervention...

  20. Control of relay structure on mineralization of sedimentaryexhalative ore deposit in growth faults of graben systems

    Institute of Scientific and Technical Information of China (English)

    XI Xiao-shuang; TANG Jing-ru; KONG Hua; HE Sho-xun

    2005-01-01

    Based on the study of ore deposits and orebody structures of two sedimentary-exhalative ore deposits,i. e. , Changba and Xitieshan Ore Deposits, it is found that the structural patterns of metallogenic basin of seafloor exhalative sulfide deposits in the ancient graben systems are controlled by relay structures in normal faults. The shapes of metallogenic basins are composed of tilting ramp, fault-tip ramp and relay ramp, which dominate migration of gravity current of ore-hosted fluid and shape of orebody sedimentary fan in the ramp. By measuring and comparing the difference of length-to-thickness ratios of orebody sedimentary fan, the result shows that the occurrence of the ramp has a remarkable impact on the shape of orebody.