Effect of Phospholipid on Pyrite Oxidation and Microbial Communities under Simulated Acid Mine Drainage (AMD) Conditions

Abstract

The effect of phospholipid on the biogeochemistry of pyrite oxidation, which leads to acid mine drainage (AMD) chemistry in the environment, was investigated. Metagenomic analyses were carried out to understand how the microbial community structure, which developed during the oxidation of pyrite-containing coal mining overburden/waste rock (OWR), was affected by the presence of adsorbed phospholipid. Using columns packed with OWR (with and without lipid adsorption), the release of sulfate (SO4(2-)) and soluble iron (FeTot) was investigated. Exposure of lipid-free OWR to flowing pH-neutral water resulted in an acidic effluent with a pH range of 2-4.5 over a 3-year period. The average concentration of FeTot and SO4(2-) in the effluent was ≥20 and ≥30 mg/L, respectively. In contrast, in packed-column experiments where OWR was first treated with phospholipid, the effluent pH remained at ∼6.5 and the average concentrations of FeTot and SO4(2-) were ≤2 and l.6 mg/L, respectively. 16S rDNA metagenomic pyrosequencing analysis of the microbial communities associated with OWR samples revealed the development of AMD-like communities dominated by acidophilic sulfide-oxidizing bacteria on untreated OWR samples, but not on refuse pretreated with phospholipid.

P8.5 - Feldeffektbasierte pH-Sensoren für die Überwachung von sauren Grubenwässern

“…Die freigesetzten H + -Ionen führen zudem zu einer sauren pH-Wertänderung. Aufgrund der unterschiedlichen Lage der Stollen kommt es zudem zu unterschiedlichen Temperaturen, Durchflussmengen, sowie geochemischen Milieubedingungen mit verschiedenen mehrfachionenangereicherten Grubenwässern [3] [4]. Beispielsweise sind die Hauptinhaltsstoffe der Grubenwässer des Lehr-und Forschungsbergwerks der TU Bergakademie Freiberg "Reiche Zeche" nach [5]: HCO3 -, Cl -, NO2 -, NO3 -, SO4 2-, Na Alternative robuste, miniaturisierbare und integrierbare pH-Sensoren, die zugleich einen geringeren Wartungsaufwand und eine erhöhte Lebensdauer aufweisen, könnten entscheidend die pH-Wert-Überwachung im Bergwerk verbessern und die Verschleißkosten und die Umweltbelastung reduzieren.…”

Characterization and reusability suggestions of the sludge generated from a synthetic acid mine drainage treatment using sodium ferrate (VI)

“…This is principally due to its acidic pH, high sulphate and dissolved metal concentrations ( Akinwekomi et al., 2017 ; Bologo et al., 2009 ; Kefeni et al., 2017 ). AMD is mostly generated when mineral sulphides are in contact with oxygen, water and catalytic bacteria ( Thiobacillus ferrooxidans ) after mining activities ( Pierre Louis et al., 2015 ; Kefeni et al., 2017 ). Therefore, its treatment is highly needed to neutralize the acidity and to reduce or completely remove metals ( Sukati et al., 2018 ).…”

Evaluation of Efficiencies of Locally Available Neutralizing Agents for Passive Treatment of Acid Mine Drainage

“…Equation 1describes pyrite oxidation when exposed to oxygen and excess water at a neutral pH. On the other hand, Equation 2utilizes Fe 3+ as the oxidizing agent with excess water and proceeds at a faster rate compared to that of Equation (1) [13]. In this case, Fe 3+ is generated by Equation 3or through iron-oxidizing bacteria [12].…”