Bioreactors for remediation of hydrocarbons in rivers and lagoons of San Luis Potosí

Abstract

In the present work the polluting hydrocarbons in water bodies of the state of San Luis Potosí were evaluated and determined in June 2019, to choose a representative carbon source for the airlift bioreactor. The sampling points were tourist areas: Chajir Lagoon, Puente de Dios pool, Tampaón River and Media Luna Lagoon, and aliphatic hydrocarbons with a carbon number between C8-C32 were found. We reported high concentrations of pollutants, such as eicosane (up to 2, 603.22 ± 1, 202.09 mg L-1) and heneicosane (up to 3, 971.21 ± 2, 260.45 mg L-1). The airlift bioreactor was designed based on hydrodynamic parameters: holdup gas Sauter mean diameter and Reynolds number that increased with the superficial gas velocity, both in the riser zone and downcomer zone and from Ug = 1.92 cm s-1, mixing and mass transfer are favoured in a 2 L airlift reactor. Also, the hydrodynamic parameters evaluated were higher in the riser zone. Furthermore, the consortium isolated by the Gutiérrez-Rojas working group composed of Xanthomonas sp., Acinetobacter Bouvetii, Shewanella Sp., and Defluvibacter lusatiensis, was able to consume 98.21% of the initial diesel concentration (13, 000 mg L-1). The airlift bioreactor evaluated in the investigation proved to be capable of remediation the studied water bodies.