Likely scenarios in the microbial leaching of gold from refractory and non-refractory ores

In this chapter, the authors describe how plant-growth-promoting bacteria is helpful for removing soil contaminants and also increasing the efficiency of phytoremediation technology. The plant growth bacteria seem almost good for removal of soil contaminants, and they can adsorb and accumulate metals in their cells and are being used in microbial leaching and also as agents of cleaning the environment.

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Color and Casta in the Andean Silver Industry

Mining Language ◽

10.5149/northcarolina/9781469654386.003.0010 ◽

2020 ◽

pp. 259-293

Author(s):

Allison Margaret Bigelow

Keyword(s):

Latin America ◽

Seventeenth Century ◽

Colonial Latin America ◽

Traditional Methods ◽

Refractory Ores ◽

Shed Light

Amalgamation technologies allowed refiners throughout colonial Latin America to profitably extract silver from a wider variety of metals, including even the most refractory ores. These expanded processing capabilities meant that mineral classification and sorting became even more important, as metallurgists had to identify which silver metals to treat with traditional methods and which ones to refine by amalgamation. The vocabularies used to classify metals provide critical evidence of Indigenous contributions to silver refining in the seventeenth century. By tracing the incorporation and removal of Andean color and spatial vocabularies, this chapter shows how scientific writers and translators replaced Indigenous classifications of matter with a racialized language of metallic “castas” that included “pacos,” “mulatos,” and “negrillos.” The chapter concludes by suggesting how a reading of color signatures in khipus might shed light on Andean miners’ experiences in ways that traditional historiographic methods have not yet allowed.

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Microbial leaching of sulfate from Illinois no. 6 coal

Resources Conservation and Recycling ◽

10.1016/0921-3449(88)90014-6 ◽

1988 ◽

Vol 1 (3-4) ◽

pp. 175-183

Author(s):

D.L. Stoner ◽

K.B. Barrett

Keyword(s):

Microbial Leaching

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Studies on Microbial Leaching of Heavy Metals from Municipal Sludge

Water Science & Technology ◽

10.2166/wst.1990.0117 ◽

1990 ◽

Vol 22 (12) ◽

pp. 229-238 ◽

Cited By ~ 22

Author(s):

R. D. Tyagi ◽

D. Couillard ◽

F. T. Tran

Keyword(s):

Ammonia Nitrogen ◽

Filter Press ◽

Vacuum Filter ◽

Continuous Stirred Tank Reactor ◽

Microbial Leaching ◽

Anaerobically Digested Sludge ◽

Air Lift Reactor ◽

Solid Liquid ◽

Air Lift ◽

Metal Solubilization

A comparative study between continuous stirred tank reactor (CSTR) with cell recycle and air-lift reactor was carried out in 30 1 capacity reactors for metal solubilization from anaerobically digested sludge. In CSTR at a residence time of 0.75 day, supplementing the feed sludge with 4 g/l of FeSO4.7H2O, using 20% sludge recycle and adjusting pH of the feed sludge to 4.5 resulted in following metal solubilization : 91% Cu, 94% Zn,, 93% Mn, 67% Cd, 67% Ni, 8% Cr, and 7% Pb. At 0.75 day retention time metals were solubilized to the recommended level in CSTR as well as in air-lift reactor. The treated sludge is easy to filter in plates filter press, centrifugation, or vacuum filter. The sludge nutrients do not seem to be diminished as a result of treatment and separation of solid-liquid. The ammonia-nitrogen fraction seems to be transformed in organic nitrogen. The decontaminated sludge produced has less odour.

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