11 Matching Results

Search Results

Advanced search parameters have been applied.
in subjects: "Ore Processing"  
Results: 1 - 11
open access

Disposal and reclamation of southwestern coal and uranium wastes

Description: The types of solid wastes and effluents produced by the southwestern coal and uranium mining and milling industries are considered, and the current methods for the disposal and reclamation of these materials discussed. The major means of disposing of the solid wastes from both industries is by land fill or in some instances ponding. Sludges or aqueous wastes are normally discharged into settling and evaporative ponds. Basic reclamation measures for nearly all coal and uranium waste disposal sit… more
Date: January 1, 1979
Creator: Wewerka, E. M.
Partner: UNT Libraries Government Documents Department
open access

Treatment of molybdenite ore with laboratory scale solar furnaces

Description: The conventional method of extracting molybdenite concentrate (MoS/sub 2/) from raw ore consumes 145 x 10/sup 6/ Btu/ton of concentrate in fossil fuel equivalent energy. Processing the ore using a solar hear source could save 56% of this energy. Thermodynamic considerations indicate that MoS/sub 2/ is the easiest of the economically valuable ores to extract using a solar heat source. Oxidation of MoS/sub 2/ to molybdic oxide (MoO/sub 3/) is an exothermic process, and it should proceed autogenic… more
Date: January 1, 1979
Creator: Coutures, J. P.; Benezech, G.; Renard, R. & Skaggs, S. R.
Partner: UNT Libraries Government Documents Department
open access

Uranium control in phosphogypsum. [In wet-process phosphoric acid production]

Description: In wet-process phosphoric acid plants, both previous and recent test results show that uranium dissolution from phosphate rock is significantly higher when the rock is acidulated under oxidizing conditions than under reducing conditions. Excess sulfate and excess fluoride further enhance the distribution of uranium to the cake. Apparently the U(IV) present in the crystal lattice of the apatite plus that formed by reduction of U(IV) by FE(II) during acidulation is trapped or carried into the cry… more
Date: January 1, 1980
Creator: Hurst, F. J. & Arnold, W. D.
Partner: UNT Libraries Government Documents Department
open access

Uptake of trace elements and radionuclides from uranium mill tailings by four-wing saltbush (Atriplex canescens) and alkali sacaton (Sporobolus airoides). [Radium 226; Uranium; Molybdenum; Selenium; Vanadium; Astatine]

Description: A greenhouse experiment was performed to determine the uptake of trace elements and radionuclides from uranium mill tailings by native plant species. Four-wing saltbush and alkali sacaton were grown in alkaline tailings covered with soil and in soil alone as controls. The tailings material was highly enriched in Ra-226, Mo, U, Se, V, and As compared with three local soils. The shrub grown in tailings had elevated concentrations of Mo, Se, Ra-226, U, As, and Na compared with the controls. Alkali… more
Date: January 1, 1979
Creator: Dreesen, D.R. & Marple, M.L.
Partner: UNT Libraries Government Documents Department
open access

Niobium - Proceedings of the international symposium

Description: This book presents the papers given at a symposium on niobium. Topics considered at the symposium included niobium mining, ore processing, uses, fabrication, microstructure, mechanical properties, physical properties, corrosion, physical radiation effects, and marketing.
Date: September 1981
Creator: Stuart, H.
Partner: UNT Libraries Government Documents Department
open access

Effects of barium chlorine treatment of uranium ore on /sup 222/Rn emanation and /sup 226/Ra leachability from mill tailings

Description: The purpose of this laboratory study was to investigate the effectiveness of barium chloride treatment of uranium ore on /sup 222/Rn emanation from mill tailings, /sup 226/Ra level in waste-water, and the leachability of radium from tailings. It has been shown that barium sulfate is an excellent carrier for radium and that barium sulfate crystals have high retention capacity for radon gas produced by radium trapped within the lattice. Ground uranium ore from a mine in Wyoming was mixed with wat… more
Date: January 1, 1985
Creator: Ibrahim, S. A.; Church, S. L. & Whicker, F. W.
Partner: UNT Libraries Government Documents Department
open access

Measurements of radon daughter concentrations in structures built on or near uranium mine tailings

Description: A technique is discussed that has been used to measure air concentrations of short-lived daughters of /sup 222/Rn in residential and commercial structures built on or near uranium mill tailings in the western part of the United States. In this technique, the concentrations of RaA, RaB, and RaC are calculated from one integral count of the RaA and two integral counts of the RaC' alpha-particle activity collected on a filter with an air sampling device. A computer program is available to calculat… more
Date: January 1, 1976
Creator: Haywood, F. F.; Kerr, G. D.; Goldsmith, W. A.; Perdue, P. T. & Thorngate, J. H.
Partner: UNT Libraries Government Documents Department
open access

Microstructural analyses of Cr(VI) speciation in chromite ore processing Residue (COPR)

Description: The speciation and distribution of Cr(VI) in the solid phase was investigated for two types of chromite ore processing residue (COPR) found at two deposition sites in the United States: gray-black (GB) granular and hard brown (HB) cemented COPR. COPR chemistry and mineralogy were investigated using micro-X-ray absorption spectroscopy and micro-X-ray diffraction, complemented by laboratory analyses. GB COPR contained 30percent of its total Cr(VI) (6000 mg/kg) as large crystals(>20 ?m diameter… more
Date: March 1, 2010
Creator: CHRYSOCHOOU, MARIA; FAKRA, SIRINE C .; Marcus, Matthew A.; Moon, Deok Hyun & Dermatas, Dimitris
Partner: UNT Libraries Government Documents Department
open access

Use of Micro X-Ray Absorption Spectroscopy and Diffraction to Delineate Cr(VI) Speciation in COPR

Description: The speciation of Cr(VI) in Cromite Ore Processing Residue was investigated by means of bulk XRD, and a combination of micro-XRF, -XAS and -XRD at the Advanced Light Source (ALS), Berkeley, CA, U.S.A.. Bulk XRD yielded one group of phases that contained explicitly Cr(VI) in their structure, Calcium Aluminum Chromium Oxide Hydrates, accounting for 60% of the total Cr(VI). Micro-analyses at ALS yielded complimentary information, confirming that hydrogarnets and hydrotalcites, two mineral groups t… more
Date: June 22, 2010
Creator: Chrysochoou, M.; Moon, D. H.; Fakra, S.; Marcus, M.; Dermatas, D. & Christodoulatos, C.
Partner: UNT Libraries Government Documents Department
open access

Treatment of molybdenite ore using a 2 kW solar furnace

Description: In the summer of 1977 several 10 g samples of molybdenite ore containing 5 to 6% Mo as MoS/sub 2/ were heated in one of the 2 kW solar furnaces at the Laboratoire des Ultra-Refractaires, Odeillo, France. The end products showed excellent separation with pure yellow acicular crystals of 99/sup +/% MoO/sub 3/ and pure white SiO/sub 2/ powder being the two major components. Impurity levels in the MoO/sub 3/ did not exceed 6000 ppM while only a small fraction of the molybdenite was entrained along … more
Date: January 1, 1978
Creator: Skaggs, S. R.; Coutures, J. P. & Renard, R.
Partner: UNT Libraries Government Documents Department
open access

USING THE SULFUR POLYMER STABILIZATION SOLIDIFICATION PROCESS TO TREAT RESIDUAL MERCURY WASTES FROM GOLD MINING OPERATIONS.

Description: Large quantities of mercury are generated as a by-product during the processing of gold ore following mining operations. Newmont Mining Corporation (NMC), which operates some of the world's largest gold mines, sought a method to permanently ''retire'' its mercury by-products, thereby avoiding potential environmental liability. Sulfur Polymer Stabilization-Solidification (SPSS) is an innovative technology developed at Brookhaven National Laboratory (BNL) for treatment of mercury and mercury cont… more
Date: February 24, 2003
Creator: BOWERMAN,B. ADAMS,J. KALB,P. WAN,R. Y. LEVIER,M.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen