Comparison of organic and inorganic chemical analysis for characterization of produced water from oil production in the Permian Basin

Abstract:

In southeastern New Mexico of Permian Basin, around 50 billion gallons of produced water is generated each year and is considered as the largest waste stream in oil and gas production industry. Produced water is composed of an extremely complex mixture of chemicals from fracturing fluids (additives), from oil-gas (native constituents), and from geologic formation (native constituents) and ubiquitous bacteria. The native constituents often include various amounts of total solids, radioactive materials, inorganic compounds, and organic compounds with widely varying molecular size and structures. These compositions vary noticeably based on the geographic location, geologic formation, the hydrocarbon products, the chemicals used by the drilling company, reservoir age, produced water storage methods, and the sample collection time. There is a lack of comprehensive understanding of flowback and produced water composition likely due to its complex matrix, lack of standard methods, and availability of instruments. This research has developed and completed several types of chemical analysis that have resulted in a comprehensive characterization and comparison of produced water chemistry from multiple sources using: 1. Liquid chromatography quadrupole time of flight mass spectrometry; 2. Gas chromatography time of flight mass spectrometry; 3. Fourier transform ion cyclotron mass spectrometry; 4. Ion chromatography and inductively coupled plasma mass spectrometry and/or optical emission spectrometry. Careful characterization using multiple instruments and methods increases our ability to address fate and transport risks, the potential impacts and risks on public health and ecological systems, and choose appropriate management practices and techniques for appropriate disposal or potential treatment and reuse.