Copper Ore Processing Research Articles

Characterization of sediments in an abandoned mining area; a case study of Mansfeld region, Germany

The distribution of selected heavy metals, including some radionuclides, metalloids and non-metals was determined in stream sediments in a region influenced by abandoned copper mining and ore processing activities. A considerable amount of the ore processing waste with a very complex composition and highly elevated concentrations of zinc, sulfur, lead, copper, arsenic, and a lot of other elements in the range between 100 and 1,000 mg/kg (Sb, Mn, Ni, Cr, Cd, Hg, and Ag) was piled up on mine dumps. The dispersion of the pollutants originating from this source and their environmental impact were investigated. Both, sediments and original waste material were studied to indicate the pathways and the mobilization behavior of different pollutants. For this purpose, the process of the elution of pollutants by application of different fractionation schemes was studied. The capabilities of different analytical techniques are shown for the analysis of solid samples (X-ray fluorescence spectrometry, Gamma-spectrometry) and liquid ones (ICP-atomic emission spectrometry, ICP-mass spectrometry and different techniques of atomic absorption). Additionally, the coupling of ion chromatography and ICP-MS detection was used to study the distribution of arsenic species in the sediment cores of a lake which acts as a natural sink for the region.

Environmental Protection Problems in the Vicinity of the Żelazny Most Flotation Wastes Depository in Poland

The Żelazny Most depository of wastes from copper-ore processing, located in southwest Poland, is the largest mineral wastes repository in Europe. Moreover, it is located in a seismically active area. The seismicity is induced and is connected with mining works in the nearby underground copper mines. Any release of the contents of the repository to the environment could have devastating and even catastrophic consequences. For this reason, geophysical methods are used for continuous monitoring the state of the repository containment dams. The article presents examples of the application of geoelectric methods for detecting sites of leakage of contaminated water and a sketch of the seismic hazard analysis, which was used to predict future seismic vibrations of the repository dams.

Using modified strong copper extractants to treat sulfidic ores

This article summarizes the evolution of modified strong copper extractants, focusing on the fairly recent requirement to effectively extract copper from high-concentration aqueous feeds derived from the hydrometallurgical processing of sulfidic copper ores.

SX-EW copper and the technology cycle

Technology is viewed to advance through a series of cycles, starting with the emergence of a major breakthrough, followed by a period of ferment as alternate designs and improvements rapidly appear, leading to a dominant design, and then a long plateau period of minor incremental change. In this paper, the technology cycle model is applied to the history of solvent extraction electrowinning (SX-EW) processing of copper ore, which, along with other innovations, has transformed the US copper mining industry. The general framework of the technology cycle model holds, although there are differences relating to the specific nature of SX-EW processing. One particularly interesting difference is that SX-EW initially was complementary to the original method of ore processing, known as flotation. Only in recent years has it directly challenged flotation in the processing of supergene or transitional ore. In addition, the analysis shows that the SX-EW process helped the US producers maintain their competitiveness for at least a decade before the process was widely adopted by their main competitors, the Chilean producers. This raises questions about the widely held assumption that research and development of new innovations can provide firms and countries with little or no competitive advantage because new technologies diffuse very rapidly in today’s global economy.

Effects of Metal Mining and Milling on Boundary Waters of Yellowstone National Park, USA.

/ Aquatic resources in Soda Butte Creek within Yellowstone National Park, USA, continue to be threatened by heavy metals from historical mining and milling activities that occurred upstream of the park's boundary. This includes the residue of gold, silver, and copper ore mining and processing in the early 1900s near Cooke City, Montana, just downstream of the creek's headwaters. Toxicity tests, using surrogate test species, and analyses of metals in water, sediments, and macroinvertebrate tissue were conducted from 1993 to 1995. Chronic toxicity to test species was greater in the spring than the fall and metal concentrations were elevated in the spring with copper exceeding water quality criteria in 1995. Tests with amphipods using pore water and whole sediment from the creek and copper concentrations in the tissue of macroinvertebrates and fish also suggest that copper is the metal of concern in the watershed. In order to understand current conditions in Soda Butte Creek, heavy metals, especially copper, must be considered important factors in the aquatic and riparian ecosystems within and along the creek extending into Yellowstone National Park.KEY WORDS: Mining; Metals; Toxicity; Biomonitoring; Copper; Yellowstone National Park

Chemistry of manganese precipitation in Pinal Creek, Arizona, USA: A laboratory study

Abstract Groundwater underlying the valley of Pinal Creek downstream from Globe, Arizona, has been contaminated by low-pH metal-enriched wastewater from copper mining and ore processing at Miami, Arizona. At present, the acidity and most of the dissolved metal content, except for Mn, of the wastewater is removed by reactions with carbonate and other solids in the alluvial aquifer before the neutralized contaminated water enters the creek channel and becomes surface flow. Where flow in the creek is perennial, Mn-bearing precipitates are formed in the stream bed and in some places in the subsurface. As an aid to understanding the processes involved and explaining the mineralogy of the precipitates, closely controlled laboratory redox titration experiments were performed on samples of surface flow and groundwater taken near the head of perennial flow in the creek. The high content of dissolved Ca, Mg, Mn and COP2 species in the neutralized contaminated groundwater caused precipitation of some of the Mn as kutnahorite, (Mn, Mg)Ca(CO3)2, when the experimental system was held between pH 8.5 and 9.0 while CO2-free air was bubbled into the solution. Hausmannite and manganite also were precipitated, in somewhat lower amounts. When the concentrations of dissolved CO2 species in the groundwater sample were decreased before the experiment was started, the Mn precipitated was predominantly in the oxides hausmannite and manganite. In some of the experimental titrations clinoenstatite, (MgSiO3), was precipitated. After titrations were stopped the solutions and precipitates were allowed to stand, with limited access to the atmosphere, for several months. During this aging period the degree of oxidation of the precipitated Mn increased and in one precipitate from an experimental solution the Ca + Mn4+ oxides todorokite and takanelite were identified. These oxides also have been identified in streambed precipitates. Some of these precipitates also gave X-ray diffraction reflections for kutnahorite. Thermodynamic feasibilities of eight potential chemical reactions forming solid phases of interest were evaluated by calculating their respective reaction affinities attained during titration and aging. The results are in general agreement with the indications for the presence of these species given by X-ray and electron diffraction. The presence of carbonates in precipitated encrustations formed from groundwater below the land surface and their occurrence in manganese oxide crusts that precipitate from the creek water, also are predicted by these results.

Optimization of Copper Ore Concentration Processing by Means of Radioactive Tracers

Flotation benefication of polymetallic ores in the Polish Lower Silesian Basin was taken as an example for the optimization of copper ore processing using radioactive tracer. An original stochastic mathematical model (stream model) was proposed to minimize copper losses in tailing. A detailed procedure of measurement was presented as well as the experimental data and their interpretation. On the basis of this research copper losses in tailing were reduced to one third.

The interaction of flotation chemistry and size reduction in the recovery of a porphyry copper ore

In the industrial-scale processing of low grade porphyry copper ores, the cost of size reduction represents the major capital and operating expense item. The goal of grinding is to achieve a small enough particle size range of the feed ore so that valuable minerals are sufficiently liberated from undesired gangue enabling the process of flotation to be efficiently used. The purpose of this paper is to demonstrate that the proper choice and use of flotation reagents, especially of the frother, can help significantly in reducing the amount of grinding required per ton of feed ore and yet maintain reasonable mineral recovery from flotation. This is achieved by using specific types of frother chemistry which enhance the recovery of coarser and partially liberated mineral particles over normal practice. A related benefit to enhanced coarse particle flotation is the minimization of mineral recovery losses associated with fine (slime) particles.

Airborne plume study of emissions from the processing of copper ores in southeastern Arizona

The elemental composition of particulate materials in the plumes of five copper smelters in southeastern Arizona was determined. Air-filter samples were collected with a light, twin-engine aircraft. Arsenic, lead, cadmium, zinc, selenium, tungsten, indium, and other volatile and chalcophilic elements are highly enriched in the plume materials relative to the background aerosol. Marked differences in the element composition of plumes from the various smelters could be used as ''''fingerprints'' to determine contributions of material from various plants at a specific impact point. (5 graphs, 27 references, 1 table)

Data evaluation in nondispersive X-ray fluorescence analysis of copper ore processing materials

The selection of exciting source both from the point of view of excitation efficiency and elimination of matrix effects using incoherently scattered radiation from the analyzed sample is discussed. Samples of materials from the flotation process of copper ore have been used and copper, iron and lead were the elements sought. For the excitation of fluorescence X-rays, sealed radioisotopic sources of238Pu,241Am,244Cm,109Cd and a molybdenum X-ray tube were used. For X-ray analysis a Si(Li) spectrometer was applied. The processing of X-ray spectra based on the application of the Gaussian peak representation gives results equivalent to the total peak area method. From the intensities of fluorescence and scattered radiation, the contents of elements were calculated using empirical formulae and the results were compared with those of the Heinrich-Rasberry method. A statistical analysis of the results has been carried out and the criteria of optimal regression formula selection are given.

Application of a simple peak shape function for the evaluation of gamma and X-ray spectra

The computational method for the rapid evaluation of gamma and X-ray spectra observed by semiconductor detectors in radiometric analysis in presented using a simple peak shape function. The computer programme includes a minimizing routine based on the modified Newton-Raphson method giving a minimized vector of the parameters more rapidly than the conventional approach. The spectra of some gamma-ray emitting fission products and X-ray spectra excited by radioisotopes of materials from copper ore processing were studied. It was found that the simple Gaussian peak function gives the results equivalent to the total peak area method.

The Hydrogeology and Utilization of Brines in El Salado, Chile

ABSTRACTThe Rio Salado catchment is located in the southern Atacama Desert. The area is distinctly arid and no ground‐water reserves originating from local recharge exist. To obtain water for a new copper ore processing plant, brines are being utilized. The complex hydrogeology of the brines from their origin in the Andes to their emergence as springs in the vicinity of El Salado is described.The surface and ground‐water discharges indicate that the long‐term supply of brine will be adequate for the processing plant. A design for abstraction incorporating three filter drains with wooden pump‐housings has been adopted to combat corrosion, incrustation and flood damage.

Climatic variations in north-central Chile from 1866 to 1971

Climatic variations in north-central Chile during the period 1866–1971 are depicted by plotting annual rainfall and other climatic data as cumulative departures from the mean. The variations are compared with world wide climatic fluctuations and a possible intensifying of existing drought conditions is forecast. The effects of decrease in precipitation over the last decade on water supplies are discussed in relation to agriculture and the processing of copper ore.