Mining processing wastes

Mining and mineral processing wastes. Certain wastes from the mining, refining, and processing of ores and minerals are excluded from the definition of hazardous waste. 

Underground injection is the subsurface emplacement of fluids through a well or hole whose depth is greater than its width. Injected fluids can include hazardous waste, brine from oil and gas production, and certain mining processes. An injection well can include a septic well, cesspool, or dry well. The SDWA allows regulation of UIC to protect usable aquifers from contamination, with additional restrictions and controls under the 1984 Amendments to RCRA. 

The U.S. Bureau of Mines-Reno Research Center is conducting research on the chemical treatment of process waste waters by ion elutriation for removing low levels of anions from cyanide solutions. This research has been coordinated with other centers for developing a waste water treatment system. 

Chemical. A chemical route is followed by two processes which are similar, the U.S. Bureau of Mines (BuMines) waste liquefaction process and the Worcester Polytechnic Institute (WPI) hydrogenation process. 

Based on the pilot-scale operation at the Britannia Mine, the vendor estimated the full-scale capital costs to be 2.5 million. Zinc and copper sulfates in the processed waste may be sold to smelters. The sale of these metals was estimated to produce a potential net operating profit for the plant of 130,000 per year (D16056F, p. 38). 

While mining processes generate metal-bearing wastes, mining wastes are outside of the current hazardous waste regulatory scope. For further information on this, refer to the current amended version of the Resource Conservation and Recovery Act (RCRA), PL 94-580, Subtitle C, Section 3001 -"Identification and Listing of Hazardous Waste."... 

Pollutant Agriculture Animal processing Chemicals Food Horticulture Metals processing Mining Municipal waste Pharmaceutical Pulp and paper Refinery Soil remediation Tanneries Textile Timber Water (potable) Water (waste)... 

Peterson, J. B. May, A. Characterization of Mining/Mineral Processing Waste Using Ox-idation/Reduction Potential and pH Measurements, Proc. Western Reg. Symp. Mining Min. Process. Wast. (Soc. for Mining, Metallurgy Exploration) 1990, 53-59. Berkeley, CA, USA, May 30-Jun 1 1990. 

Other heavy metals are also toxic, but fortunately are less widespread and are present in smaller amounts. Mine tailings (waste rock remaining after the valuable minerals have been removed) and waste material from processing plants are major sources of such metals. Many major rivers and lakes have sources of metal contamination from industries whose processes were developed and facilities were built before control of waste was recognized as a major problem. 

Table 9.1 lists some metals which may be recovered and purified commercially by ion exchange whether from process waste streams or primary ore treatments. Because of the increasing demand on the Worlds s natural mineral resources there is an important need for efficient, and economic, methods of treating low grade ores, waste mine waters, mineral dumps, and discarded tailings. 

Voluminous uranium mining and processing wastes, since only a very small percentage of uranium bearing ore is beneficially used... 

In some mining processes, the taihngs water may contain reagents that have to be treated before the slurries can be pounded, f or instance, free cyanide or dissociable cyanide species must be treated to immobilize them in the taihngs impoundment. The addition of ferrous sulfate solutions to cyanide-laden waste streams will sequester free cyanide in a stable precipitate known as Prussian blue, fC)ll c(t N)(,I3. More stringent treatment methods, such as Caro s acid (concentrated sulfuric acid and hydrogen peroxide), destroy most cyanide species as ammonia or nitrogen and CO2. 

F. M. Doyle and A. H. Mirza, Understanding the Mechanisms and Kinetics of Acid and Heavy Metals Release from Pyritic Wastes, in Mining and Mineral Processing Wastes, F. M. Doyle (ed.), SME, Littleton, CO, 1990, pp. 43-51. 

Transmutation is a treatment that converts molecules with a long half-life into molecules with shorter half-lives (making required storage times shorter). This process could be used with spent nuclear fuel, to permit some re-use of material. However, such recycling produces additional radioactive and chemical wastes, as well as creating short-term handling hazards. Further, it is considerably cheaper to mine and process uranium ore than it is to re-process wastes. 

The Environmental effects resulting from the uranium mining activities are mainly derived from the wastes generated by the ore processing. Wastes... 

Akcil, A., and T. Mndder. 2003. Microbial destruction of cyanide wastes in gold mining process review. Biotechnol. Lett. 25(6) 445-50. 

The material properties of the various categories of mineral processing wastes are influenced by the characteristics of the parent rock, the mining and processing methods used, and the methods of handling and/or disposing of the mineral by-product [99-112]. The physical and chemical properties of waste rock, mill tailings, and coarse coal refuse are summarized and discussed in Table 12. 

In general, the inner interlocked low tail laneway is laid immediately adjacent to the return airway in the process of the support design, the roof pressure between roadways and the dynamic pressure should be taken into account especially in the mining process, the effect of the inner interlocked low tail laneway should be considered fully, that is to say, the support strength should be considered fully, otherwise, once the mining causes the collapse of the inner interlocked tail roadway, all the previous efforts will be wasted. 

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