Content of PetroWiki is intended for personal use only and to supplement, not replace, engineering judgment. SPE disclaims any and all liability for your use of such content. More information
Recycling hydraulic fracturing wastewater
Water management can significantly add to the cost and environmental footprint of oil production and innovations in water management can provide significant economic and environmental gains. New treatment technologies make recycling of hydraulic fracturing water possible.
- 1 Methods for recycling wastewater
- 2 Benefits of wastewater recycling
- 3 Cost of wastewater recycling
- 4 Prevalence of wastewater recycling
- 5 References
- 6 Noteworthy papers in OnePetro
- 7 External links
- 8 See also
Methods for recycling wastewater
Methods for recycling fracking water include anaerobic and aerobic biologic treatment; clarification; filtration; electrocoagulation; blending (directly diluting wastewater with freshwater); and evaporation.
EMIS. 2010. Anaerobic Biological Wastewater Treatment. (February 2010 version). http://emis.vito.be/techniekfiche/anaerobic-biological-wastewater-treatment?language=en (accessed 16 February 2015).
Generally, anaerobic treatments on wastewater are implemented on concentrated wastewater. Anaerobic sludge contains a variety of microorganisms that cooperate to convert organic material to biogas via hydrolysis and acidification. Biogas typically consists of 70% methane (CH4) and 30% carbon dioxide (CO2) with residual fractions of other gases (e.g. H2 and H2S). The methane can be used as an energy source. Anaerobic reactors can be implemented in a variety of ways. (The figure shows a contact reactor and an upflow reactor. The sludge is mixed with wastewater in the reactor, then separated in the sedimentation tank and returned to the reactor. In the anaerobic upflow reactor, the influent is introduced at the bottom of the vertical reactor. The primarily grain-shaped sludge forms a blanket in the reactor, with the most compact sludge grains at the bottom and the lighter grains and heavier sludge floccules above it. Light sludge floccules are released by the upward flow, but can potentially be collected in a sedimentation tank. Biogas is collected and disposed of at the top of the reactor, separately from the partially purified water and the sludge.
Benefits of wastewater recycling
Factors driving the conservation of water include the limitations in sources of fresh water in areas with a high rate of development, attractive economics of recycling compared with tanker truck transportation costs, minimization of road traffic to reduce environmental impacts, and water disposal costs.
Cost of wastewater recycling
Prevalence of wastewater recycling
After stimulation treatment, water used to fracture the well, in amounts as large as 50%, can rise back to the surface, along with the initial production, as flowback water. Flowback and produced waters, both part of the production stream, must be separated from the formation. In most cases, flowback and produced water are disposed into an injection well, put in evaporation ponds, or treated and disposed of according to government regulations. Water management can significantly add to the cost and environmental footprint of oil production and innovations in water management can provide significant economic and environmental gains. New treatment technologies make recycling of water recovered from hydraulic fracturing possible. Methods for recycling fracking water include anaerobic and aerobic biologic treatment, clarification, filtration, electrocoagulation, blending (directly diluting wastewater with freshwater), and evaporation. Recycling of produced water and fracture flowback water for reuse in hydraulic fracturing is on the rise in the development of unconventional resource plays. Factors driving the conservation of water include the limitations in sources of fresh water in areas with a high rate of development, attractive economics of recycling compared with tanker truck transportation costs, minimization of road traffic to reduce environmental impacts, and water disposal costs.
Use this section for citation of items referenced in the text to show your sources. [The sources should be available to the reader, i.e., not an internal company document.]
Noteworthy papers in OnePetro
Use this section to list papers in OnePetro that a reader who wants to learn more should definitely read
Use this section to provide links to relevant material on websites other than PetroWiki and OnePetro
Use this section for links to related pages within PetroWiki, including a link to the original PEH text where appropriate