Application of an emulsified polycolloid substrate biobarrier to remediate petroleum-hydrocarbon contaminated groundwater. (March 2019)

• Record Type: Journal Article
• Authors: Lee, T.H.; Tsang, D.C.W.; Chen, W.H.; Verpoort, F.; Sheu, Y.T.; Kao, C.M.
• Is Part Of: Chemosphere. Volume 219(2019)
• Page Start: 444
• Page End: 455
• Publication Date: 2019-03
• Subjects: Permeable reactive barrier -- Emulsified polycolloid substrate (EPS) -- In situ bioremediation -- Toluene partition -- Petroleum hydrocarbon; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2018.12.028
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Emulsified polycolloid substrate (EPS) was developed and applied in situ to form a biobarrier for the containment and enhanced bioremediation of a petroleum-hydrocarbon plume. EPS had a negative zeta potential (−35.7 mv), which promoted its even distribution after injection. Batch and column experiments were performed to evaluate the effectiveness of EPS on toluene containment and biodegradation. The EPS-to-water partition coefficient for toluene (target compound) was 943. Thus, toluene had a significant sorption affinity to EPS, which caused reduced toluene concentration in water phase in the EPS/water system. Groundwater containing toluene (18 mg/L) was pumped into the three-column system at a flow rate of 0.28 mL/min, while EPS was injected into the second column to form a biobarrier. A significant reduction of toluene concentration to 0.1 mg/L was observed immediately after EPS injection. This indicates that EPS could effectively contain toluene plume and prevent its further migration to farther downgradient zone. Approximately 99% of toluene was removed after 296 PVs of operation via sorption, natural attenuation, and EPS-enhanced biodegradation. Increase in total organic carbon and bacteria were also observed after EPS supplement. Supplement of EPS resulted in a growth of petroleum-hydrocarbon degrading bacteria, which enhanced the toluene biodegradation. Highlights: EPS was developed to form a biobarrier for petroleum-hydrocarbon containment. Toluene has high sorption affinity to EPS (EPS to H2 O partition coefficient = 943). EPS could contain toluene plume and prevent its migration to downgradient aquifer. EPS enhanced in situ toluene biodegradation under anaerobic conditions.