Cyanide treatment of mining tailings using suspended biomass and moving bed biomass reactors
Por:
Julieta Alvillo-Rivera, Angelica, Esperanza Garrido-Hoyos, Sofia, BUITRON, GERMAN
Publicada:
1 may 2022
Resumen:
Mexico is the top producer of silver and is on the eighth place from
producing gold in the world. For instance, the hydrometallurgical
extraction process produces wastewater (mining tailing) characterized by
being composed with varying concentrations of cyanide and heavy metals.
The purpose of this research was to study the biodegradation of cyanide
contained in mining tailings by means of a bacterial consortium isolated
from a tailings dam. For this purpose, three types of Eckendfelder
reactors were used, one with suspended biomass (BS) and two moving bed
biofilter reactors, one with biomass immobilized on Kaldnes (BK)
supports, and the other on polyurethane cubes (BCP). Three experimental
stages were worked; in each of them, the concentrations of total cyanide
were varied. In the first one, it was 26 +/- 2 mg.L-1; in the second one
40 +/- 4 mg.L-1; and the third one 55 +/- 4 mg.L-1. During the whole
operation, the pH and temperature were maintained at 9.5 units and 25
degrees C. After 141 days of operation, biodegradation of the total
cyanide contained in the mining tailings was 69% (17 mg.L-1) in the BS
reactor, while in the BK reactor, it was 93% (3.9 mg.L-1) and in the
BCP reactor 95% (2.5 mg.L-1). The predominant families in each of the
reactors, as well as their respective relative abundances, were for the
BS and for the BK of Cyclobacteriaceae (20.65% and 24.64%) and
Rhizobiaceae (18.48% and 14.01%) and Halomonadaceae (46.97%) and
Hyphomonadaceae (24.94%) in the BCP.
Filiaciones:
Univ Nacl Autonoma Mexico, Fac Ingn, Inst Mexicano Tecnol Agua, Campus Morelos, Jiutepec, Morelos, Mexico
Inst Mexicano Tecnol Agua, Blvd Paseo Cuauhnahuac 8532, Jiutepec 62550, Morelos, Mexico
Univ Nacl Autonoma Mexico, Campus Juriquilla, Juriquilla, Queretaro, Mexico
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