ANALYSIS OF ORGANIC COMPOUNDS PRODUCED FROM HIGH TEMPERATURE AND PRESSURE FLUID-ROCK REACTIONS

During hydraulic fracturing, engineered fluid is pumped into organic rich shale formations, inducing fractures, and providing an environment in which fluid-rock reactions occur under elevated pressure and temperature. Prior analysis and research shows these reactions can result in the proliferation of low molecular weight organic compounds (LMWOCs) within produced water that returns to the surface. Data concerning LMWOCs in produced waters from natural gas is limited to a few studies and the chemical reactions occurring between hydraulic fracturing fluid and the organic matter of the fractured source rock are not completely understood. The goal of this study is to use static autoclave experiments to emulate the in-situ fluid-rock environment in order to better understand the source and fate of organic molecules during hydraulic fracturing. Temporal analysis of fluid from autoclave experiments and characterization of extracted kerogen will provide information into the source of organic compounds and how subsurface reactions evolve during hydraulic fracturing. Specific compounds of interest include benzene, toluene, ethylene, and xylene, as they represent the most common LMWOCs found in produced water and pose a high contamination threat during hydraulic fracturing. This study is expected to provide insight into the source of organic compounds in produced waters, while also contributing to the growing database of organic compounds associated with hydraulic fracturing.