Mining waste stream

Alternative water-treatment technologies have recently been developed and applied for the treatment of mine-site effluents. Biologically mediated systems that reduce sulfate and promote the precipitation of insoluble metal sulfides have been developed for treatment of mine-waste streams. Reverse-osmosis systems have been applied for treatment of mine-waste effluents, or for polishing the effluent from facilities that use lime treatment. 

Potential for Future Recovery from Mine Waste Streams (Y/N) Potential for recovery and new byproduct uses from historic and future mine waste streams ... 

Removing suspended inorganic material from waste streams generated in the beneficiation of ores or nonmetalHc minerals, to form a concentrated slurry that can be used for reclamation of mined out areas or other uses and a clarified water that can be discharged or recycled. 

PermeOx is also used to improve the bioremediation of soils contaminated with creosote or kerosene (see Bioremediation (Supplement)), to deodori2e sewage sludges and wastewater (see Odormodification), and to dechloriaate wastewater and effluents. A special formulation of calcium peroxide, made by FMC and sold ia the United States under the trademark Trap2ene, is used for removing metal ions from acidic waste streams such as coal ash leachate and acid mine drainage (see Wastes, industrial). 

Sulfur can be produced direcdy via Frasch mining or conventional mining methods, or it can be recovered as a by-product from sulfur removal and recovery processes. Production of recovered sulfur has become more significant as increasingly sour feedstocks are utilized and environmental regulations concerning emissions and waste streams have continued to tighten worldwide. Whereas recovered sulfur represented only 5% of the total sulfur production ia 1950, as of 1996 recovered sulfur represented approximately two-thirds of total sulfur production (1). Recovered sulfur could completely replace native sulfur production ia the twenty-first century (2). 

In the liquid-hquid extraction area, in the mining industry, coming out of the leach tanks is normally a slurry, in which the desired mineral is dissolved in the liquid phase. To save the expense of separation, usually by filtration or centrifugation, attempts have been made to use a resident pump extraction system in which the organic material is contacted directly with the slurry. The main economic disadvantage to this proposed system is the fact that considerable amounts of organic liquid are entrained in the aqueous slurry system, which, after the extraction is complete, is discarded. In many systems this has caused an economic loss of solvent into this waste stream. 

An American Salt Company plant and the Dow Chemical Company s Midland plant also benefit directly from each other s presence. Dow found that after recovering bromine from brine it had more salt left than it desired. American Salt needed salt. By locating next to Dow s plant it was able to buy this salt stream for less than it would cost to mine it or pump it from natural underground reservoirs. In turn, Dow was able to sell an unwanted stream that it would otherwise have had to pump back into the ground. The American Salt plant is typical of many satellite plants. These are plants that either use a by-product or a waste stream from another plant or are built mainly to supply a needed chemical to an adjacent plant. The nearby presence of another plant determines their location. 

Populations of freshwater oligochaetes and leeches were reduced in numbers of individuals and numbers of taxa in mine tailing effluents containing 146 to 213 pg Zn/L or sediments containing >20 g Zn/kg DW (Willis 1985b). Leeches (Erpobdella octoculata) experienced a reduction in density and reproductive capacity in streams containing 25 to 310 pg Zn/L from mine wastes and did not avoid these harmful concentrations (Willis 1989). 

KEYWORDS stream sediment, natural background levels, chemical fluxes, phase analysis, historical mine waste... 

The country-wide dataset of stream sediment analyses in Austria consists of 36,136 samples analyzed for 34 chemical elements (Fig. 1), (Thalmann et al. 1989). Complemented by local surveys of hydrochemistry, whole rock geochemistry, soil chemistry and mineralogical phase analyses, these data are used to derive natural background levels of different rock units, investigate chemical fluxes between soil, rock and groundwater, and evaluate the emission risks of historical mine waste. 

Combining data from stream sediment analyses with data on historic mining areas, the emission risks of old mine waste sites are evaluated systematically throughout Austria. Univariate and multivariate statistics serve to identify areas with naturally, or anthropogenically, elevated heavy metal concentrations (Fig. 4). Lead and zinc mineralization for... 

The INCA system can recover virtually any target metal in any aqueous waste stream containing up to 60% solids. Applications include on-site remediation of mining effluents and contaminated groundwater. The INCA system can also be used as an in-process treatment system for manufacturing processes where metals in solution are a problem. The modular unit can easily be used in tandem with other technologies, such as those that remove hydrocarbons, as part of a total treatment train. 

Even explosives must conform to regulations. Polymer bound explosives (PBXs) and Class 1.1 military propellants have been reformulated for use in the mining industry. There is a minimal waste stream (Wulfman et al., 1997). 

Extraction of metals for 125 years generated extensive hazardous waste in the area around the Montana Rocky Mountains. About 5-7% of all rivers in Montana—more than 2000 km of streams—are contaminated by mining wastes at a level that impairs beneficial use of water (Montana Department of Health and Environmental Sciences, personal communication). Central to this contaminant burden is the wastes generated by mining and... 

Italy Sardinia Baccu Locci streams Ore deposits and mining wastes Frau and Ardau (2003)... 

Iron phosphate CBPCs may provide inexpensive means to recycle these waste streams. Iron mine tailings and red mud may be recycled in building components by fabricating ceramics from them at ambient temperature. Iron-rich swarfs may be recycled if a way is found to solidify these fines into pellets and feed them back into a blast furnace. Thus, iron phosphate CBPCs facilitate solidification of iron-rich waste streams and recycling. 

In spite of this limitation, the method is very useful, because it provides a means of forming a ceramic of one of the most common and inexpensive oxides. As discussed before, iron oxide is a component of lateritic soils and red mud, high-volume iron mine tailings, and machining swarfs. Thus, useful products of several mineral waste streams can be formed by the process described in this chapter. Development of ceramics using red mud and swarfs is discussed in Chapter 14. 

Cohen, R.R.H. (2006). Use of microbes for cost reduction of metal removal from metals and mining industry waste streams. J. Cleaner Prod. 14 1146-57. 

The waste streams in standard metallurgical processing are good potential sources of important elements. The U.S. Bureau of Mines has developed processes for the recovery of elemental sulfur from stack gases discharged by base metal smelters (G4) and for the recovery and production of alumina from waste solutions of mining operations (G6). A potential of 1,750,000 tons of sulfur per year and an estimated 2000 tons of alumina per day are recoverable just from 14 copper mines included in the study. 

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