A Microbial Consortium for the Bioremediation of Sulfate-Rich Wastewater Originating from an Edible Oil Industry

Abstract

The effluents from industries processing vegetable oils are extremely rich in sulfates, often exceeding the maximum concentration allowed to release them to the environment. Biological sulfate reduction is a promising alternative for the removal of sulfates in this type of wastewater, which has other particularities such as an acidic pH. The ability to reduce sulfates has been widely described for a particular bacterial group (SRB: sulfate-reducing bacteria), although the reports describing its application for the treatment of sulfate-rich industrial wastewaters are scarce. In this work, we describe the use of a natural SRB-based consortium able to remove above 30% of sulfates in the wastewater from one of the largest edible oil industries in Peru. Metataxonomic analysis was used to analyse the interdependencies established between SRB and the native microbiota present in the wastewater samples, and the performance of the consortium was quantified for different sulfate concentrations in laboratory-scale reactors. Our results pave the way towards the use of this consortium as a low-cost, sustainable alternative for the treatment of larger volumes of wastewater coming from this type of industries.