Environmental impacts of replacing slickwater with low/no-water fracturing fluids for shale gas recovery

Citation:

W. Lin, Bergquist, A. M., Mohanty, K. K., and Werth, C. J., “Environmental impacts of replacing slickwater with low/no-water fracturing fluids for shale gas recovery,” ACS Sustainable Chemistry & Engineering, vol. 6, no. 6, pp. 7515-7524, 2018.

Abstract:

The environmental impacts of a typical hydraulic fracturing operation for shale gas recovery were evaluated using life cycle assessment, with energy demands for well drilling and fracturing determined from GHGfrack model. Dominant environmental impacts stem from well construction, which are >63% in all categories (e.g., global warming and eutrophication), and mainly due to diesel fuel combustion and steel production. The relative impacts related to water use (i.e., fracturing fluid components, water/wastewater transportation, and wastewater disposal) are relatively small, ranging from 5 to 22% of total impacts in all categories; freshwater consumption for fracturing is also a small fraction of available water resources for the shale play considered. The impacts of replacing slickwater with CO2 or CH4-foam fracturing fluid (≤10 vol % water) were evaluated; total impacts decrease <12%, and relative impacts related to water use decrease to 2–9% of total impacts. Hence, switching to a foam-based fracturing fluid can substantially decrease water-related impacts (>60%) but has only marginal effects on total environmental impacts. Changes in lateral well length, produced to fresh-water ratios, fracturing fluid composition, and LCA control volume do not change these findings. More benefits could potentially be realized by considering water versus foam-related impacts of ecological health and energy production.

Notes:

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