Sandstone Ore Research Articles

Quantitative Detection of Quartz Sandstone SiO2 Grade Using Polarized Infrared Absorption Spectroscopy with Convolutional Neural Network Model

As an independent characteristic of electromagnetic radiation, the polarization of light is sensitive to the scattering and absorption characteristics of the mineral particles. The combination of polarization and infrared absorption spectroscopy is conducive to rapidly and accurately detecting the SiO2 content of metallurgical sandstone deposits. In this study, the 8–14 μm polarized infrared absorption spectra and the grade of the sandstone ore samples were used to analyse the spectral characteristics of the sandstone powder samples. Principal component analysis (PCA) and the successive projection algorithm (SPA) were used to reduce the dimension of the original data, first-order derivative, reciprocal logarithm, and multivariate scattering correction (MSC) data. Then, generalized regression neural network (GRNN), partial least squares regression (PLSR), and convolutional neural network (CNN) were employed to establish a hyperspectral prediction model of SiO2 grade. The results show that the quantitative model by the PCA-CNN algorithm has the better prediction precision for the reciprocal logarithm data, with a coefficient of determination (R2), root mean square error (RMSE), and ratio of performance to interquartile range (RPIQ) of 0.907, 0.023, and 5.11, respectively. This method indicates that the polarized infrared absorption spectra and the PCA-CNN model can provide a more robust and significant spectral interpretation than single infrared spectra, and it is expected to be applied to any high-purity quartz deposit type for in situ and rapid analysis.

Preparation of gamma alumina nanoparticles from kaolinitic sandstone and their application as a selective adsorbent for REEs from liquid waste

A process for synthesizing Gamma alumina from kaolinitic sandstone ore has been described in this paper. Fine kaolin was recovered from the sandstones after aggressive attrition scrubbing process followed by 2" and 1" hydro- cyclone classification. The produced −25 μm kaolin was transformed to active meta-kaolin via calcination at 750 °C for 5 h. Through metakaolin- H2SO4 interactions, and consequently precipitation in ethanol solution, aluminum sulfate was formed. After dryness and calcination at 900 °C for 2 h γ-alumina was prepared. The FT-IR, DLS, BET, XRD, SEM and EDX analyses confirmed the high purity of the nanosized γ-alumina product. In addition, the prepared γ-alumina was examined as the sorbent for rare earth species from waste materials. Adsorption and thermodynamic studies, in addition to the adsorption selectivity, desorption process, and reusability showed promising performance results. The maximum adsorption capacity of the prepared γ-alumina reached 142 mg/g.

Neo-Assyrian Ferrous Industry at the Western Frontier of the Empire: The Iron Workshop at Tel Sera', Israel

Excavations at Tel Sera' (esh-Shari'a), yielded unique evidences for iron production in the courtyard of a Neo-Assyrian fortress. The assemblage is the most complete to have been found in the Neo-Assyrian Empire, with a singular case of an in-situ iron furnace. In addition, remains of further production, such as iron ore, furnace fragments, tuyeres, slag, and hammerscales, were collected and analyzed.This find offers a unique opportunity to apply analytical analysis to an Assyrian iron workshop, the only one excavated thus far within the confines of the empire, with solid archaeological context. Using microscopical and analytical methods, we argue that all stages of iron production were performed at Tel Sera'. Ferruginous sandstone ores were transported to the site and beneficiated before smelting. They were smelted in a furnace made from a ceramic fabric designed to withstand thermal stress. Immediately afterward, they were foraged into artifacts. This enterprise was performed under the direct control of the agents of the Neo-Assyrian Empire stationed on the Egyptian frontier. It is the only example of iron processing found in pure Neo-Assyrian contexts. Finally, we discuss the implications of this in the historical context of the Iron Age Southern Levant.

Undisturbed iron industry sites in the Sonian Forest, Belgium

In the Sonian Forest of Middle Belgium, undisturbed remnants of ancient metallurgic activity, dating from the Early Middle Ages, are found. They occur in an area with iron-rich geological formations at shallow depth below a loess cover. Iron-industry traces include scoria mounds, which always occur in pairs. Associated with each pair is a single large zone with a reddish-pink colour of the upper part of the soil. These zones were formed by heating of the soil from the surface, most likely during roasting of the iron sandstone ore as pretreatment. The surface horizon was later homogenised by biological activity, down to the top of the Bt horizon or the compacted part of the E horizon. Charcoal mounds, whose distribution is not clearly related to that of other archaeological structures, date at least partly from more recent periods. Another associated feature is an area with a surface cover of yellowish sands, representing a site where the sandstone was unloaded or cleaned before further treatment. The preservation of these various features related to ancient metallurgic activity is due to the unique land-use history of the Sonian Forest, where a centuries-long continuous prohibition of agricultural practices has prevented the destruction of shallow surface structures.

Study on leaching systems and recovery for PALUA–PARONG low grade uranium sandstone ores

The study on treatment of Palua-Parong uranium low grade ores by different techniques: agitation leaching, strong acidic pugging and curing, and heap leaching was carried out on laboratory and pilot scales. The experimental conditions during the leaching process for uranium recovery from ore such as time, ground particle size, acid influence and temperature effect were investigated. The bench scale experiments developed in a laboratory were tested in pilot with 100 kg of ore sample for each batch. From the experimental results, the heap leaching method was proposed to treat this ore on large scale. The uranium recovery efficiency at pilot scale reached over 80%. The concentration and purification of uranium leached liquor was examined by anion exchange method using Amberlite IRA-420 and INDION GS300 resins. Uranium loading on INDION GS300 resin was approximately 85% that of Amberlite IRA-420.

Comparative Analysis of the Strength Distribution for Irregular Particles of Carbonates, Shale, and Sandstone Ore

The article presents the results of investigations on three lithological types of Polish copper ore: sandstone ore, carbonate ore, and shale ore. According to X-ray diffraction analysis, sandstone samples can be classified as sandstone with dolomite binder and partly clay binder; shale—as dolomitic slate with a high proportion of clay with elevated organic matter content; while dolomite has a high organic content. Five particle-sized fractions (16–18 mm, 18–20 mm, 20–25 mm, 25–31.5 mm, and 31.5–45 mm) of each lithological type were prepared. A single-axis slow-compression test was performed on single particles to determine the value of the crushing force. The Weibull distribution was used to approximate the strength distribution models and cumulative strength distribution functions for each of the materials. The residual deviation and non-linear correlation coefficient were calculated in order to assess the fitting of the model function to empirical data. In addition, the impact of particle size on the strength of the raw material was separately investigated for the hard (dolomite and shale) and soft brittle material (sandstone).

Technology of Polish copper ore beneficiation – perspectives from the past experience

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.

Mineralogical and Geochemical Studies on Manganese Deposits at Abu Ghusun Area, South Eastern Desert, Egypt

Mineralogical and Geochemical Studies on Manganese Deposits at Abu Ghusun Area, South Eastern Desert, Egypt I. A. Salem, N. H. El-Shibiny, M. Abdel Monsef Abstract The Abu Ghusun manganese deposit is subjected to mineralogical and geochemical studies in order to elucidate its petrogenesis. Manganese occurs as sheets, lenses, encrustation and fracture filling within clastic sediments of the Abu Ghusun Formation of Oligocene age. The mineralogical, and geochemical data confirmed by microscopic investigations, X-ray diffraction (XRD), infrared absorption spectrometry (IR), differential thermal analyses (DTA), thermo gravimetric (TG), environmental scanning electron microscope (ESEM) and chemical analyses of major and trace elements. The results showed that Abu Ghusun manganese deposits include two different ore types: 1- massive ore and 2-manganiferous sandstone ore. The main mineralogical composition of manganese ore types are pyrolusite, psilomelane, rhodochrosite and hematite. The gangue minerals are quartz, feldspar, rock fragments, apatite and calcite. The geochemistry of Abu Ghusunmanganiferous sandstone and massive ore types indicated that they are rich in Cr (60, 58 ppm), Zn (132, 200ppm), Ba (12050, 1414 ppm), Sr (3400, 353 ppm) and V (156, 196 ppm) respectively. The discrimination diagrams based on major and trace elements also indicated that Abu Ghusun manganese deposit is a hydrothermal origin. The manganiferous sand stone (40.9% MnO2) and the massive ore types (48.1 % MnO2) lie in the field of high grade B.. Full Text: PDF DOI: 10.15640/jges.v4n2a4

Ion exchange resin selection for concentration and purification of uranium leached by sulphuric acid solution

Ion exchange is one of the most popular techniques for recovery and purification of uranium from sulfuric acid leaching solution, especially for recovery of uranium from a low uranium containing solutions. Resins commonly used are strong base or weak base anion resins with amine functional group. The anionic form of resins may be NO3-, Cl- , SO­42- or OH-. The selection of a resin depends on the uranium total exchange capacity, selectivity and the cost. The previous studies often use Amberlite IRA-420 for concentration and purification of uranium solution from Pa Lua sandstone ores. This is a good and suitable resin but high price. To diversify the resins and reduce the costs, instead of IRA-420, the authors tested two commercial resins Indion GS300 (India) and Purolite A400 (UK) in the processing of uranium solution from sandstone ores. The results showed that the uranium total exchange capacity of these resins is only about 80 - 85% over Amberlite IRA-420, but these resins should be able to be used instead of Amberlite IRA-420 due to their low cost and availability in Vietnam.

Studying on design of a complet pilot plant for processing sandstone ores in Pa Lua – Pa Rong area

Design, construction and operation of a pilot for processing uranium containing ores are important stages in the process of project development of uranium production from ores because uranium contained minerals and the composition of minerals are unstable factors. In this case, pilot needs to be a simulation of a plant in the future, but with upgrade equipment compared that at laboratory scale. Results of lab research were used to select the most appropriate process for ore processing and selection of equipment for each stages.
 In the circumstance when there has been a lack of experience in processing uranium ores in Vietnam, the design and construction of such a pilot with completed technological procedures are essential. The main purpose of this work is to verify results of lab researches and optimize operational parameters of the process. In addition, several purposes were also considered such as study on the effects of solution circulation/recycling and accummulation of impurities in a long run; obtain necessary and sufficient information for design, cost estimate for investment and operation... The pilot only can achieve the expected objectives when ore sources (including reserves and characteristics) are determined; a complete technological process for obtaining technical uranium (yellowcake) is designed; investment and operational capitals are estimated and these estimates show the costs and benefits of the process.
 In this article, the authors will focus on the presentation of research results, including data on ore, process technology, material balance, pilot scale, the basic parameters of equipments, installation diagram of equipments, construction, power and water needs identification, preliminary calculation of investment and operational costs.

Geometallurgy and processing of North Ras Mohamed poly-mineralized ore materials, South Sinai, Egypt

The present work aims to study the link between mineralogy and process characteristics of North Ras Mohamed ore materials. The chemical nature of the latter was also studied to determine the type of treatment employed from one hand and the preferred lixiviate option from the other hand.For this purpose, three technological samples representing three different deposit types were examined for their potential processing options. These include basal sandstone, aplite dyke and pegmatitic bodies which were found to assay 0.05, 0.04 and 0.06% U, 0.13, 0.10 and 0.07% Th and 0.14, 0.13 and 0.09% REEs respectively, while Nb assays 1.3% and Ta 0.5%, in the pegmatitic ore sample. The corresponding minerals of these elements of interest include thorite and uranothorite in the basal sandstone ore material. On the other hand, the multiple-oxide minerals samarskite, fergusonite and allanite are found in both the aplite and the pegmatite bodies. However, the zircon, fluorite, apatite, titanite and brookite are considered as the main accessory minerals in the three study ore materialsBased on the available chemical and mineralogical data on the three different ore material types of Ras Mohamed area, a physical upgrading process would be required as a major recommendation for future prolific metallurgical work.

LA-ICP-MS trace element analysis of pyrite from the Chang'an gold deposit, Sanjiang region, China: Implication for ore-forming process

The Chang'an gold deposit, Yunnan province is one of five large gold deposits in the Ailaoshan gold belt that is the most important ore belt of the Sanjiang Tethyan metallogenic domain. Geochemical study of pyrite in the deposit was conducted using laser ablation inductively coupled plasma mass spectroscopy. Three types of hydrothermal pyrite were identified in the ores and wall rocks, i.e., the coarse euhedral crystals in syenite (Py1), the coarse grains disseminated in altered sandstones or sandstone ores (Py2), and the fine-grained euhedral pyrite in sandstone ores (Py3). Their trace elements exhibit different concentrations, associations and rim–core zoning, implying different geneses and crystallization processes. The cores of Py1 were formed by magmatic fluids and have the lowest concentrations of Au, As, Cu and Zn. The cores of Py2 were formed by metamorphic fluids and have relatively high Au, Ag, Ni, Pb and Cu concentrations. The Py3 grains and the growth rims of Py1 and Py2 show consistently high contents of Au, As, Pb and Co, suggesting that all of them were rapidly deposited from a mixing fluid system that was probably composed of fluids of metamorphic and magmatic origins. This interpretation is supported by the observation that the high-grade ores generally contain lots of Py2 and Py3. Hence we consider that the deposit was formed during India–Asia collision, slightly postdate the 33–35Ma tectono-magmatism.

The Application of Modern Techniques and Measurement Devices for Identification of Copper Ore Types and Their Properties / Wykorzystanie nowoczesnych technik i urządzeń pomiarowych do identyfikacji typów rud miedzi i ich właściwości

The paper concerns the application of modern methods and research techniques for investigations of copper ore properties. It presents the procedure and tools which, when put together, can constitute a source of information on properties of different products of processing and, simultaneously, can be used in the process control and optimization. The copper ore of one of the branches of the KHGM Polska Miedz plc was investigated. The ore samples represented each of the three lithological types occurring in the Polish deposits, i.e. carbonate, shale and sandstone ores. The paper presents the results of microscopic analyses, image analysis of scanning photographs and application procedures of the obtained information for the identification of ore types (application of neuron networks to the recognition of lithological compositions). The present publication will present sample results of modelling of classification identifying two types of ores, i.e. carbonate-shale and sandstone. Summing up the predictions of ore type fractions in respective mixtures for the considered problem of classification it can be stated that the prediction results are good and confirm the lithological predominance of certain ore types in the investigated mixtures. The experimental part comprised the determination of mineralogical and lithological composition of ores (optical microscope) and also elemental composition in the microareas of analysed samples (scanning microscope). Next, the image analysis was performed and subsequently the models classifying the ore types were made.

Discussion on Geological Experiment Technology in Geological Work

This essay puts silicate rocks test as example on the basic of the analysis of new technology and method of geological experiment. This essay analyses the experimental principal and process of silicate rock’s total iron content, and it based on geology experimental operation process. The essay tries to probe into silicate rock’s mineral chemical composition, rock structure and tectonics through the research of the iron content and other chemical components of silicate rocks. Furthermore, this essay also estimates the optional mineral’s component content of sandstone ore, and then evaluates mining products and industrial and economic value. It is very important to guide the development of the mine.

The use of scanning electron microscopy and an electron microprobe in studies on oxidation of sulfur compounds by bacteria and bioleaching of heavy metals

We present results obtained during studies on oxidation of reduced sulfur compounds by Thiobacillus neapolitanus and bioleaching of copper from limestone and sandstone ore. We have used simple and cheap methods for visualisation of chemical and biological phenomena in microscale involving examination with scanning electron microscope and electron microprobe.

The use of scanning electron microscopy and an electron microprobe in studies on oxidation of sulfur compounds by bacteria and bioleaching of heavy metals

We present results obtained during studies on oxidation of reduced sulfur compounds by Thiobacillus neapolitanus and bioleaching of copper from limestone and sandstone ore. We have used simple and cheap methods for visualisation of chemical and biological phenomena in microscale involving examination with scanning electron microscope and electron microprobe.

Geochemical hosts of solubilized radionuclides in uranium mill tailings

The solubilization and subsequent resorption of radionuclides by ore components or by reaction products during the milling of uranium ores may have both economic and environmental consequences. Particle-size redistribution of radium during milling has been demonstrated by previous investigators; however, the identification of sorbing components in the tailings has received little experimental attention. In this study, uranium-bearing sandstone ore was milled, on a laboratory scale, with sulfuric acid. At regular intervals, filtrate from this suspension was placed in contact with mixtures of quartz sand and various potential sorbents which occur as gangue in uranium ores; the potential sorbents included clay minerals, iron and aluminum oxides, feldspar, fluorspar, barite, jarosite, coal, and volcanic glass. After equilibration, the quartz sand-sorbent mixtures were separated from the filtrate and radioassayed by gamma-spectrometry to determine the quantities of 238U, 230Th, 226Ra, and 210Pb sorbed, and the radon emanation coefficients. Sorption of 238U was low in all cases, with maximal sorptions of 1–2% by the bentonite- and coal-bearing samples. 230Th sorption also was generally less than 1%; maximal sorption here was observed in the fluorspar-bearing sample and appears to be associated with the formation of gypsum during milling. 226Ra and 210 Pb generally showed higher sorption than the other nuclides - more than 60% of the 26Ra solubilized from the ore was sorbed on the barite-bearing sample. The mechanism (s) for this sorption by a wide variety of substrates is not yet understood. Radon emanation coefficients of the samples ranged from about 5 to 30%, with the coal-bearing samples clearly demonstrating an emanating power higher than any of the other materials.

Isotopic Disequilibrium of Uranium in Kansas Groundwaters

Isotopic Disequilibrium of Uranium in Kansas Groundwaters

Stable isotope constraints on the role of graphite in the genesis of unconformity-type uranium deposits

The Key Lake unconformity-type uranium deposit occurs in a shear zone where it intersects the unconformity between Archean and Aphebian gneisses and the overlying Proterozoic Athabasca Group sandstones. The roots of the Key Lake and many other unconformity-type uranium deposits in the Athabasca basin are close to gneisses rich in graphite and most deposits have small amounts of carbonaceous materials (bitumen and hydrocarbon buttons) within and around altered basement and sandstone ore zones. In many Athabasca uranium deposits, hydrothermal fluids have destroyed graphite disseminated in the strongly altered gneisses in the vicinity of the deposits, prompting some to suggest that graphite was converted to CH4, which reduced and precipitated the uranium and partially condensed to form bitumen. The δ13C values of graphite collected from unaltered and altered gneisses around the Key Lake deposit have a limited range (−25 ± 5) and are not a function of distance from the mineralization or the intensity of alteration or deformation. The uniformity of these δ13C values suggests that the destruction of graphite was due predominantly to oxidation by basinal fluids from the sandstone and that the graphite near the deposits did not react to form substantial amounts of 12C-rich phases such as CH4. Most of the bitumen samples, which have higher H/C ratios than the graphite, have δ13C values identical to those of the graphite (−25 ± 5). The similarity in the isotopic compositions of carbon in the bitumen and in the graphite indicates that the bitumen formed from degradation of graphite as a result of reactions with no significant isotopic fractionations, such as ones involving radiolysis of graphite. The hydrocarbon buttons and a few samples of bitumen have petrographic relations and 13C/12C ratios (δ13C values less than −30) that are indicative of reduction of graphite by H2 produced from water by radiolysis. Graphite in these deposits did not play a central role as a reducing agent for uranium, rather it represents a critical structural factor by providing shear zones along which fluid flow can be focussed.

Analysis of variance in investigations on anisotropy of Cu ore deposits

The problem of variability of copper grades and ore thickness in the Lubin copper ore deposit in southwestern Poland is presented. Results of statistical analysis of variations of ledge parameters carried out for three exploited regions of the mine, representing different types of lithological profile show considerable differences. Variability of copper grades occurs in vertical profiles, as well as on extension of field (the copper-bearing series). Against the background of a complex, well-substantiated description of the spatial variability in the Lubin deposit, a methodology is presented that has been applied for the determination of homogeneous ore blocks. The method is a two-factorial (cross) analysis of variance with the special tests of Tukey, Scheffe and Duncan. Blocks of homogeneous sandstone ore have dimensions of up to 160,000 m2 and 60,000 m2 in the case of the Cu content parameter and 200,000 m2 and 10,000 m2 for the thickness parameter.