Insolubilización biológica del cromo en aguas residuales de la industria de curtiembre

Abstract

Within the present investigation, wastewater from tanning was characterized and microorganisms were identified from several isolations of water and residual sludge to make a reduction of the hexavalent chromium that is present in the tanning process of the "Curtiduría Serrano" Industry located in the province of Tungurahua. Biostimulation was performed on the tanning waters and the sludge resulting from the insitu treatment, microorganisms with different morphological characteristics were isolated. The identification of the microorganisms was carried out from Microgen GN ID A+B biochemical tests and complementary tests such as the oxidase test and test in SIM medium. The three most efficient microorganisms were identified as Pseudomonas fluorescens (60.61%), Pseudomona stutzeri (46.55%) and Acinetobacter lwoffii (46.35%). The bacterial growth curves were determined, where it was observed that the three bacteria that best adapted to the concentration of 2500 ppm of chromium on average were Pseudomonas fluorescens, Pseudomona stutzeri and Acinetobacter lwoffii. The biotransformation potential of the resistant microorganisms found at the site of contamination, specifically in the water and sewage sludge from the tanning process where high concentrations of chromium are present, was evaluated and is recommended for future use as an alternative technology.