The impact of ethanol blend releases to the aesthetic quality ofgroundwater and the indigenous microbial community

[摘要] A pilot-scale aquifer system was used to evaluate groundwater quality impactsfrom a continuous release of an aqueous 10% v:v ethanol solution mixed with benzeneand toluene (50 mg/L each). The geochemical footprints (methane, volatile fatty acids(VFAs), pH, oxidation reduction potential (ORP), dissolved oxygen (DO) andtemperature) were monitored over 11 months. The accumulation ofVFAs (particularlybutyric acid) during the summer exceeded the secondary maximum contaminant levelvalue for odor, which represents a previously unreported aesthetic impact. Temperaturevariations (3.9 to 30.0 °C) significantly affected microbial activities, and a strongcorrelation was observed between groundwater temperature and CH4/VFAs generation(p < 0.05). Quantitative real-time PCR (qPCR) analysis showed that ethanol blendincreased the microbial population and enriched the fermentative groups foracetogenesis and methanogenesis.

[发布机构] Rice University

[效力级别] engineering