Biodegradação de inibidores de incrustações por microrganismos

Abstract

Oil and gas as fossil sources play a relevant role when compared to other energy sources. Industrial development has been increased the global energy demand, and its essential to increase oil reserves and production capacity. However, its extraction is challenging and uses a series of complex procedures, which aim to extract the maximum from these reserves. Many of these techniques are based on stimulating the well by injecting fluids. Scale inhibitors are needed, because in oil industry operations, there is a risk of scale deposition. They can cause the malfunction of pumps and other equipment, deposit along the pipes, reducing the internal diameter of tubes which can block the flow of fluids. Many of these compounds contain carbon, nitrogen and phosphorus, among other elements that serve as substrate, as stimulants or as inhibitors factors for microorganisms' growth that ause damage such as scale and corrosion. Thus, the objective of this study is to evaluate the effect of different scale inhibitors on the concentration of microorganisms, typical of a production system, and to evaluate the consumption of these products as sources of carbon, nitrogen and phosphorus. The microorganisms studied were Pseudomonas aeruginosa, Shewanella algae, Desulfovibrio desulfuticans and a consortium of sulfate reducing bacteria. To do so, the composition of the ideal culture medium was established for each microorganism, as well as the concentration of inoculum to be used and the concentration of the additive used in the tests. Then, the microbial growth was monitored under the etermined culture conditions, in the presence and absence of chemical additives. The results showed different degrees of growth of the microbial species, depending on the composition of the medium and the concentration of chemical additive. Moreover, the use of the additives as a source of nutrient (phosphorus, nitrogen and carbon) was observed for each species.