Water treatment, mine waste

Among the basic fields of applications, the major use of acrylamide polymers is liquid-solid separation in water treatment and waste treatment. Smaller quantities are used in the manufacturing of paper and in the processing of minerals in mining. Relatively nonlarge quantities are use as additives for enhanced oil recovery. 

Geochemistry and mineralogy of ochre precipitates formed as waste products of passive mine water treatment... 

The liquid mine wastes are mainly represented by underground drainage waters (up to 2000 m3/day and even more), as well as low radioactive waste water from uranium treatment plants (from 100 up to 300 m3/day). The uranium isotopes, radium-226, thorium-230, polonium-210, lead-210 are the most dangerous. Their total activity in waste waters reaches often 10-50 Bq/L at the MPC values for natural waters of 0.111 Bq/L. 

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. 

Kunze, C., 2003, Handling, treatment and disposal of naturaUy occuring radioactive wastes (NORM) from mining and water treatment. In Hehenstreit, C., Kudelko, J., and Kulczycka, J. (Eds.) Mine Waste Management - Best AvaUahle Techniques, Krakow 2003, p. 186. 

The chemical intermediates adiponitrile and acrylamide have surpassed nitrile rubbers as end-use products of acrylonitrile in the United States and Japan. Adiponitrile is further converted to hexamethylenediamine (HMDA), which is used to manufacture nylon 6/6. Acrylamide is used to produce water-soluble polymers or copolymers used for paper manufacturing, waste treatment, mining applications and enhanced oil recovery (Langvardt, 1985 Brazdil, 1991). 

Occupational exposures may occur in the production of hydrogen peroxide, in waste-water treatment, metal cleaning, and chemical synthesis, and in the textile, pulp and paper, geothermal energy and mining industries (lARC, 1985). 

Jenke DR, Diebold FE. Electroprecipitation treatment of acid mine waste-water. Water Res 1984 18 855-859. 

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. 

Figure 14 Schematic diagram of a mine-waste impoundment with a combined remediation approach, including a cover to prevent O2 and water ingress, in situ mixing to geochemically stabilize waste, permeable reactive barrier in aquifer to treat subsurface drainage, and wetland for surface treatment of drainage.

Many industrial processes rely on effective agitation and mixing of fluids. The application of agitators cover the areas of mining, hydrometallurgy, biol-ogy, petroleum, food, pulp and paper, pharmaceutical and chemical process industry. In particular, in these industries we find typical chemical reaction engineering processes like fermentation, waste water treatment, hydrogenation, polymerization, crystallization, flue gas desulfurization, etc [65, 21]. 

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