Desulfovibrio and Pseudomonas Dominated Enriched Produced Water Reinforcing their Importance in Oilfields and Production Processes

Abstract

Enrichment based isolation methods and molecular identification were used to investigate the microbial communities in produced water obtained from Periquito (PQO) and Galo de Campinas (GC) onshore oilfields in Brazil. Produced water was enriched with Postgate B, Postgate C and Baars media and incubated. DNA was extracted, PCR amplified and16S rDNA fragments were sequenced using Illumina TruSEq. 4.2 million reads were analysed and deposited at the Sequence Read Archive at NCBI. No significative differences in microbial community composition could be attributed to the enrichment but significant differences were observed from two oil fields. The dominant Bacterial Orders detected from both oilfields were Desulfovibrionales, Pseudomonadales and Enterobacteriales. Pseudomonas were found predominantly in Periquito oilfield (19.8%) with only 2,4% at Galo de Campinas. Pleomorphominas (3.76%) and Shewanella (4,69%) were exclusive to and possible biomarkers for the Periquito Oilfield. 11.05% and 7.62% of the sequences were not classified at genus level and detected at GC and P. Abundances changed for Desulfovibrio from P, 29.8% at PQO and 16.08% at GC. The Clostridium_sensu_stricto varied from 2.8% at PQO and 2.4% at GC). Pseudomonas were found predominantly in Periquito oilfield (19.8%) with only 2,4% at Galo de Campinas. Pleomorphominas (3.76%) and Shewanella (4,69%) were almost exclusive to and possible biomarkers for the Periquito Oilfield. These data provide a bacterial biodiversity benchmark for future produced water treatment and microbially enhanced oil recovery (MEOR).

Metagenomic assessment of nitrate-contaminated mine wastewaters and optimization of complete denitrification by indigenous enriched bacteria

“…Among the common metabolisms predicted in both samples, there was nitrate reduction and nitrogen and nitrate respiration, which play roles in N-cycling in the environment. Genera of bacteria responsible for nitrate metabolisms, such as Bacillus, Clostridium, and Citrobacter, were concurrently detected in the samples, and the metabolic predictions further validate their presence in the mine wastewater samples (Kisková et al, 2018;Tiburcio et al, 2020). Nitrification and Frontiers in Environmental Science frontiersin.org ammonium oxidation metabolic pathways both result in the formation of NO 3 − and were exclusively predicted in the Pt-SA sample that had the highest nitrate concentrations (177 mg/L), which strongly suggests that nitrifying bacteria converts NH 4 + and NO 2 − to NO 3 − (Spangler and Gilmour, 1966;Kim et al, 2005).…”

Effect of Environmental Factors on Accumulation of Trace Metal in a Typical Shale Gas Exploitation Area: A Comprehensive Investigation by Empirical and Geodetector Models

“…Recent studies had identified several ways leading to the release of such elements into soil during shale gas exploitation process. For one thing, the disposal of untreated wastewater and leaching of poorly managed drilling wastes by rainwater o breakage of pipelines would directly generate release of heavy metals (Vidic et al, 2013;Cliffe et al 2020;Chen et al, 2020;Bonetti et al 2021;Tiburcio et al 2021). For another, the surface activities associated with shale gas development and migration of natural gas from deep to upper soil due to casing/cement failures could change mobilization of heavy metals (Brantley et al 2014;Bondu et al 2021;Zhou et al, 2023).…”