Query: Abu tartur

title: Radiological assessment of Abu Tartur phosphate, Western Desert Egypt.
abstract: The contents of natural radionuclides (226)Ra, (232)Th and (40)K) were measured in sedimentary phosphate rock samples (Abu Tartur phosphate, Western Desert Egypt) by using gamma spectrometry (NaI (Tl) 3"x 3" Phosphate and environmental samples were collected from Abu Tartur phosphate mine and the surrounding region. The results are discussed and compared with the levels in phosphate rocks from different countries. The activities of (226)Ra, (232)Th series and (40)K are between (14.9 0.8 and 302.4 15.2) (2.6 1.0 and 154.9 7.8) and (10.0 0.5 and 368.4 18.4) Bq kg( 1) respectively. The Abu Tartur phosphate deposit was found to have lower activity than many others exploited phosphate sedimentary deposits, with its average total annual dose being only 114.6 microSv y( 1) This value is about 11.46% of the 1.0 mSv y( 1) recommended by the International Commission on Radiological Protection (ICRP 60, 1990) as the maximum annual dose to members of the public.

title: Recovery of lanthanides from Abu Tartur phosphate rock, Egypt
abstract: In the present work, a process for the treatment of Abu Tartur phosphate rock for the recovery of lanthanides without interfering with the normal route proposed for fertilizer production, is proposed using HNO 3 as a leaching agent. Further, an attempt was made to defluorinate the leach solution in order to upgrade the fertilizer and, at the same time, recover the fluorine. A significant benefit of Abu Tartur phosphate rock processes for the recovery of the lanthanides lies in their relatively high content of lanthanides (averaging 0.11% while the produced fertilizer would pollute the environment less with radioactive materials due to the low uranium content (averaging 25 mg/kg) A further advantage of phosphate rock as a source of rare earth products is the absence of radioactive thorium, the safe disposal of which is vexatious to monazite based processes.

title: The Cretaceous glauconitic sandstones of Abu Tartur, Egypt
abstract: Die Abu Tartur Mine befindet sich in der Western Desert, 50 km westlich der Stadt El Kharga in Agypten. Geologisch wird das Abu Tartur Plateau hauptsachlich von oberkretazischen (Campan Maastricht) Phosphoriten, welche wirtschaftlich genutzt werden, Schwarzschiefern und Glaukoniten aufgebaut. Die Phosphat haltigen Ablagerungen sind von grosem wirtschaftlichen Interesse und werden seit ihrer Entdeckung im Jahr 1967 genutzt. Ein Profil der Sedimentabfolge wurde aufgenommen, sedimentologisch beschrieben, charakterisiert, und die einzelnen Schichten beprobt. Weiters wurde eine spezielle Glaukonitlage detailliert mineralogisch und chemisch untersucht und mit einer Glaukonitprobe aus der Mine verglichen. Aufgrund der Sedimentabfolge konnten zwei Ablagerungsbereiche interpretiert werden: 1) ein hemipelagisches Environment im Tiefwasser, wo Phosphorite und an organischem Kohlenstoff reiche Tone abgelagert wurden und 2) ein flacheres, hoher energetisches Schelf Environment mit der Ablagerung von Glaukoniten. Von einer sequenzstratigraphischen Perspektive: 1) wurde wahrend eines Transgressiven Systemtrakts (TST) und eines fruhen Hochstands (HST) abgelagert und 2) wahrend des mittlerern und spaten Meerespiegel Hochstands und eines Niedrigstand progradierenden Fachers (Glenn Arthur, 1990) Petrologische und rasterelektronenmikroskopische Untersuchungen verdeutlichen die authochtone Bildung der Glaukonitkorner. Mittels Rontgendiffraktometrie (XRD) Mikrosondenmessungen und Dunnschliffanalysen wurden chemische, morphologische und farbliche Unterschiede der Oberflachenproben AT 31 bis AT 36 und der frischen Minenprobe festgestellt. Die frischen Glaukonitkorner der Minenprobe sind, verglichen mit den Oberflachenproben, reich an Fe2O3 und K2O. Dies veranschaulicht, dass die Oberflachenproben starker Verwitterung ausgesetzt wurden. XRD Analysen der <2 um Fraktionen der Proben zeigen, dass die Glaukonitkorner aus Illit (Glaukonit)/Smektit Wechsellagerungsmineralen bestehen. In der Minenprobe ist der Anteil der Illitlagen im Wechsellagerungsmineral jedoch hoher (80% als in den Oberflachenproben (52% Das Ladungsdiagramm Muskovit Pyrophyllit Seladonit zeigt einen klaren Trend von smektitischem Glaukonit zu illitischem Glaukonit. Die Minenprobe plottet exakt im Glaukonitfeld. Die Ergebnisse verdeutlichen, dass die Oberflachenproben durch die Verwitterung stark verandert sind. Glaukonit verandert sich durch die Verwitterung kontinuierlich von einem illitahnlichen Mineral zu einem Fe reichen Illit/Smektit Wechsellagerungsmineral und schlieslich zu Smektit. Fur alle chemischen und mineralogischen Untersuchungen an glaukonitischen Oberflachenproben mussen diese starken Verwitterungseffekte berucksichtigt werden.

title: ENRICHMENT OF ABU TARTUR PHOSPHATE ORE WASTES
abstract: In this work, the amenability of upgrading the reject generated from beneficiating Abu Tartur phosphate ore by magnetic separation was investigated by two methods: leaching with acetic acid solutions and froth flotation. The reject is characterized by its ferriferous dolomite impurities. To optimize the leaching process, the effects of grain size, acetic acid concentration, acid/solid ratio and the reaction time on loss on ignition percent were investigated. The results of this series of experiments gave unsatisfactory results. Separation of phosphate minerals from the associated impurities has been successfully achieved by flotation. The studied parameters such as particle size distributions, conditioning time, mode of collector addition and depressant type were investigated to reach optimum conditions. The experimental results show that, it is possible to obtain phosphate concentrate assaying 30% P2O5 and 0.75% MgO with P2O5 recovery of about 75% from a feed assaying 23% P2O5 and 3.77% MgO.

title: Extraction of Uranium from "Abu Tartur" Phosphate Aqueous Leachate Solution
abstract: Uranium was effectively extracted from a synthetic aqueous monocalcium phosphate/phosphoric acid mixture (MCP/H3PO4) by tri n octylamine dissolved in different solvents and the presence of low concentrations of some counteranions (oxalate, citrate, chloroacetate) in the aqueous phase. The extraction efficiency was markedly enhanced by the salting out action of the concentration of calcium ions in the MCP/H3PO4 solution.

title: Sedimentological and technical studies on the montmorillonitic clays of abu tartur plateau, western desert, Egypt
abstract: One of the most known sedimentary formation among Egyptian Upper Cretacous rock units is named Duwi Formation (Lower Maastrichtian) an outcrop at the Abu Tartur plateau, Kharga Oasis, Western Desert, Egypt. This formation displays three montmorillonitic clayey layers. The investigations of these sediments provide information on the texture, constituents and type of clay minerals, which helps define and describe their physical and technical properties. Granulometrically, the selected samples have siltstone, mudstone and claystone facies. Mineralogical analysis of the studied deposits proved that the clay minerals compose mainly of montmorillonite, in addition to small amount of glauconite, and traces of illite. Scanning electron microscopy revealed three main micro structures, namely honeycomb, matrix, and turbulent. Acid activation of eight samples was performed using hydrochloric acid. The efficiency of activation was examined by measuring their bleaching capacity to crude cotton seed oil, and changes in their surface areas. The acid treatment resulted in more than 4 fold increase in the activity of the pretreated bentonite samples. The extent of activation was found to be pronounced after the first 30 minutes of acid treatment.

title: SEDIMENTOLOGICAL AND TECHNOLOGICAL STUDIES OF ABU TARTUR BLACK SHALES, WESTERN DESERT, EGYPT
abstract: Newly conventional combination of sedimentological and technological studies aid in estimation of the resource potential of the Upper Cretaceous clays of Duwi Formation Abu Tartur plateau Western Desert, Egypt. This formation consists of interbedded black to Grey shale, phosphatic and glauconitic sandstones. The granulometric, mineralogical, and geochemical analyses were carried out on the black clays, which provided detailed information about textural parameters, composition and paleoenvironment of deposition The technological studies of black shale is new for its interesting enrichments in various rare metals as nickel chromium and vanadium This investigation is a laboratory study for extraction of vanadium from black shales by hydrochloric acid processing to produce leach solutions of vanadium, aluminum and magnesium chlorides. The effects of various factors affecting the leaching process such as temperature, acid concentration, particle size and stirring speed as well as the kinetics of the leaching process were studied. The most favorable conditions for the extraction of the vanadium present in the black shale are temperature 100deg C, acid concentration 6 M by weight, grain size 17 um and leaching time 90 min.

title: SURFACE SUBSIDENCE PREDICTION OVER WORKING LONGWALL PANEL AT ABU TARTUR PHOSPHATE MINES
abstract: The phenomenon of subsidence is the movement at the ground surface caused by underground excavations, which can cause severe damage to buildings or structures on the surface and infrastructure. These excavations exert redistribution of the original stresses around the openings. Different methods have been adopted to predict and quantify the subsidence with the subsidence parameters. These methods can be classified into three categories 1) Empirical methods based on the analysis of the field measurement, 2) Mathematical theories, 3) Numerical models including Finite Elements, Boundary Elements and Distinct Elements methods. In this paper, the surface subsidence data were collected over working longwall panel at Abu Tartur phosphate mines after the face had been advanced 280m. Different mathematical theories namely Bals' Peng's, Knothe's and Peck's theories are applied to predict the subsidence trough over the excavated panel. The obtained results are compared with the measured ones. It was found that Peck's theory coincides well with the measured data. The degree of ground surface tilt, surface curvature and strain are derived from Peck's theory.

title: Characterization and separation of pyrite from Abu Tartur black shale
abstract: This work aimed for pyrite separation from Abu Tartur black shale as a source of sulfur to be an added economic value of Abu Tartur area. The considered samples in the present work were collected from a core drilled in Abu Tartur plateau representing the pyrite rich black shale of the U. Cretaceous age. Sample characterization was carried out using petrographic microscope, XRD, DTA/DTG, C/S and XRF techniques. Clay minerals, silt sized quartz, calcite, and hematite were the main minerals associating pyrite (5.34% Liberation behavior of the sample was about 80% below 5 mm. Sample processing was achieved through one day soaking followed by classification using 1 inch Mozley hydro cyclone where about 35.5% by weight went to underflow and 64.5% went to overflow. The underflow product was subjected to an advanced gravity separation process using SB 40 Falcon Concentrator through a CCD statistical design prepared by Design Expert 6.0 software proposed to optimize the separation process through a study for the effects of frequency (Hz) and water pressure (Psi) on both assay and recovery of the sulfur rich heavy fraction. A heavy concentrate weighed 10.90% with inorganic sulfur content reached 11.37% (21.24% pyrite) with overall recovery (50.01% was obtained after two cleaning at the optimum conditions.

title: Chemical weathering of the economic phosphates of Abu Tartur, Western Desert, Egypt
abstract: The Upper Cretaceous economic phosphates of Abu Tartur are affected by chemical weathering which imparts brownish hues to the surface exposures. Weathering is responsible for a series of mineral alterations as well as mobilization of several trace elements. The calculations of the chemical formula of apatite indicate that it is stable in the prevailing weathering environments and it has the composition of carbonate fluorapatite. Pyrite and mixed layer clays, on the other hand, are found to be readily vulnerable to attack by weathering. Hematite "limonite" and gypsum/anhydrite are formed in the weathering zone at the expense of pyrite and epidiagenetic calcic cement. Also, illite, authigenetic silica and halite are enriched at the expense of smectite chlorite mixed layer clays and carbonates. The trace elements Zn and Sr are enriched whereas Co, Ni, Cu, Pb and Ba are depleted in the weathering zone. Some elements, including V, Cr and the rare earths, seem not to have been affected by the prevailing weathering.