Title: | Volatile-organic molecular characterization of shale-oil produced water from the Permian Basin |
Author(s): | Khan NA; Engle M; Dungan B; Holguin FO; Xu P; Carroll KC; |
Address: | "New Mexico State University, Las Cruces, NM, USA. U.S. Geological Survey, El Paso, TX, USA. New Mexico State University, Las Cruces, NM, USA. Electronic address: kccarr@nmsu.edu" |
DOI: | 10.1016/j.chemosphere.2015.12.116 |
ISSN/ISBN: | 1879-1298 (Electronic) 0045-6535 (Linking) |
Abstract: | "Growth in unconventional oil and gas has spurred concerns on environmental impact and interest in beneficial uses of produced water (PW), especially in arid regions such as the Permian Basin, the largest U.S. tight-oil producer. To evaluate environmental impact, treatment, and reuse potential, there is a need to characterize the compositional variability of PW. Although hydraulic fracturing has caused a significant increase in shale-oil production, there are no high-resolution organic composition data for the shale-oil PW from the Permian Basin or other shale-oil plays (Eagle Ford, Bakken, etc.). PW was collected from shale-oil wells in the Midland sub-basin of the Permian Basin. Molecular characterization was conducted using high-resolution solid phase micro extraction gas chromatography time-of-flight mass spectrometry. Approximately 1400 compounds were identified, and 327 compounds had a >70% library match. PW contained alkane, cyclohexane, cyclopentane, BTEX (benzene, toluene, ethylbenzene, and xylene), alkyl benzenes, propyl-benzene, and naphthalene. PW also contained heteroatomic compounds containing nitrogen, oxygen, and sulfur. 3D van Krevelen and double bond equivalence versus carbon number analyses were used to evaluate molecular variability. Source composition, as well as solubility, controlled the distribution of volatile compounds found in shale-oil PW. The salinity also increased with depth, ranging from 105 to 162 g/L total dissolved solids. These data fill a gap for shale-oil PW composition, the associated petroleomics plots provide a fingerprinting framework, and the results for the Permian shale-oil PW suggest that partial treatment of suspended solids and organics would support some beneficial uses such as onsite reuse and bio-energy production" |
Keywords: | "Environmental Monitoring/*methods Gas Chromatography-Mass Spectrometry Minerals/analysis Oil and Gas Fields/*chemistry Texas Volatile Organic Compounds/*analysis Wastewater/*chemistry Water Pollutants, Chemical/*analysis Gas chromatography mass spectromet;" |
Notes: | "MedlineKhan, Naima A Engle, Mark Dungan, Barry Holguin, F Omar Xu, Pei Carroll, Kenneth C eng Research Support, Non-U.S. Gov't England 2016/01/24 Chemosphere. 2016 Apr; 148:126-36. doi: 10.1016/j.chemosphere.2015.12.116. Epub 2016 Jan 21" |