Chemicals in Hydraulic Fracturing

Detection of fracturing-related chemicals in treatment plant effluent (© 2015 ACS)*

Hydraulic Fracturing Chemicals: Applications, Transformation Reactions and Water Treatment

Multi-stage hydraulic fracturing (HF) in combination with horizonzal drilling have led to a steep rise in unconventional gas exploitation. Large volumes of water are injected under pressure to fracture the formation and to release entrapped gas bubbles. The gas is subsequently collected at the surface together with the flowback (the reemerging fracturing fluid) and formation water (the emerging geogenic fluid). For process optimization multiple chemical additives are employed. Much societal concern centers on these additives and on geogenic chemicals emerging from the deep subsurface. In addition, transformation products may be formed in subsurface reactions. Knowing their identity and properties is important in the case of spills and accidents, and it is pivotal to design adequate wastewater treatment and disposal.

Projects

  • Qualitative survey and structural classification of HF Chemicals
  • Background sampling in areas prior to HF activities
  • Groundwater quality assessment in areas with HF activities
  • Wastewater treatment plant effluent assessment
  • Flowback water analysis
  • Transformation products

Publications

  • Down et al, Appl. Geochem, 2014: Pre-drilling background groundwater quality in the Deep River Triassic Basin of central North Carolina, USA; doi:10.1016/j.apgeochem.2015.01.018
  • Elsner et al, ES&T, 2015: Comment on the German Draft Legislation on Hydraulic Fracturing: The Need for an Accurate State of Knowledge and for Independent Scientific Research, doi: 10.1021/acs.est.5b01921
  • GdCH, 2015: Deklaration ohne Wenn und Aber- Wasserchemiker fordern Offenlegung aller Fracking-Chemikalien
  • Getzinger et al, ES&T, 2015:Natural Gas Residual Fluids: Sources, Endpoints and Organic Chemical Composition after Centralized Waste Treatment in Pennsylvania, doi: 10.1021/acs.est.5b00471

*Adapted with permission from Getzinger et al.: Natural Gas Residual Fluids: Sources, Endpoints, and Organic Chemical Composition after Centralized Waste Treatment in Pennsylvania, Environ. Sci. Technol. Copyright 2015 American Chemical Society.