The New Reality of Hydraulic Fracturing: Treating Produced Water is Cheaper than Using Fresh

Abstract

Simple, cheap, and reliable treatment of produced water will transform the economics and viability of unconventional plays. Produced water recycle not only creates options to minimize fresh water usage; in local areas it can take tens of thousands of water hauling trucks off the road and significantly reduce salt water disposal. This is no pipe dream. A novel process based on a step-change in the application of chlorine dioxide chemistry has been proven to work and consistently generate frac-compatible fluid at several company facilities in Texas. The solution is an inline system that simplifies the operation, optimizes chemical consumption, and enables continuous on-the-fly treatment. Case studies over multiple years and greater than 18 million barrels used at the field level show that produced water is being recycled for less than half the equivalent cost of using fresh water.

Will Water Issues Constrain Oil and Gas Production in the United States?

“…PW reuse for HF is facilitated by recent advances in HF water chemistry that allow the use of PW with minimal treatment, i.e., “clean brine” with TDS up to ∼260 000 mg/L. , Besides, regulations have been introduced to promote reuse of PW for HF by changing PW storage regulations. For example, New Mexico modified its regulations (Rule 34) to allow PW reuse/recycling without a permit for drilling, completion, and production and allow recycling containment facilities to be operated for up to 5 years, subject to annual renewals, to enhance potential PW reuse …”

National Alliance for Water Innovation (NAWI) Resource Extraction Sector Technology Roadmap 2021

“…Reclamation and reuse of the water within industry (especially O&G production) has increased in the last decade due to improvements in extraction chemicals and processes. 18,19,20 Yet, reuse of the waters generated, including extracted formation water, remains the most significant challenge for both O&G and mining given the high TDS and challenging constituents. Reuse is often facilitated by removal of precipitable TDS and heavy use of additives.…”

“…Advances in hydraulic fracturing chemicals have allowed for internal reuse of high salinity produced water but come with an increase in chemical costs. 90 Often, reuse as "clean brine" requires minimal treatment of constituents like residual oil, TSS, bacteria, and iron. Clean brine is often generated via conventional treatment (i.e., coagulation, flocculation, and sedimentation) to remove solids and iron followed by disinfection.…”

“…Potential options are heavily influenced by produced water quality and regulatory constraints. 20 For example, low salinity, high-quality produced water has been successfully treated to allow for long-term irrigation of almonds, citrus, and a variety of vegetable crops in California for over two decades. 92,93 However, widespread use of produced water for irrigation is limited, as utilization of lower quality produced water for irrigation will require substantial treatment and cost to mitigate potential impacts to plant and soil health.…”

The Role of Membrane-Based Technologies in Environmental Treatment and Reuse of Produced Water

“…The two most common applications for reusing PW in the energy sector are enhanced oil recovery (EOR) and makeup water used for hydraulic fracturing fluid (Khatib, 2007;Graham et al, 2015;Arora and Dagar, 2019); for these applications, high salt concentrations do not preclude use, and thus, only minimal PW treatment may be required for reusage (Webb and Zodrow, 2020). PW reuse for hydraulic fracturing requires efficient removal of solids and iron (≤10 mg/L) (Munirasu et al, 2016;Nadella et al, 2020); in addition, it is necessary to inactivate microorganisms to reduce the chance of well clogging and damage (Barnes et al, 2015). For EOR use, filtration may be implemented to remove further targeted particles (Shams Ashaghi et al, 2007;Buono et al, 2019).…”