THE WATER ISSUE/
Produced Water Management EMBRACING SCALABLE, INNOVATIVE SOLUTIONS IN NORTH AMERICA By Abheek Banerjee, Exterran
P
roduced water management has evolved significantly over the past decade, especially in the U.S. unconventional market as water volumes continue to increase. Compared to the Middle East, however, management of produced water in the U.S. unconventional space continues to be handled on a smaller scale (<100,000 BPD). Individual operators tend to work in pockets and deal only with their own produced water even though this is an issue that neighboring fields and facilities also experience. With pipelines and infrastructure development on the rise, the industry needs to consider consolidated, large-volume treatment. If scaled correctly and in conjunction with newer, innovative technologies, this approach opens doors to producers and mid-streamers to benefit from simplified facility designs, economies of scale and higher process efficiencies. The emergence of environmental, social and governance (ESG) and sustainability as key strategic components for stakeholders further supports the argument for consolidated and innovative produced water management.
CHALLENGES
The volatility and unpredictability of oil prices remains one of the biggest hurdles steering operators away from medium- to long-term contracts for water management. Short-term or “frack-on-the-fly” models will not work for large-volume facilities. Further, drilling programs are often tied to oil prices and steady produced water flow rates cannot be guaranteed, which impacts projected plant utilization and resulting economics. Another challenge that prevents large-volume treatment is the sharing of water between operators — this can be difficult if partnering operators are hesitant to accept another operator’s water quality specifications. Lastly, this industry can also be reluctant to change and 24
Well Servicing Magazine/December 2021
embrace newer technologies, which calls for a shift in mindset and approach to move forward and understand the potential benefits.
RECENT ADVANCEMENTS
A notable change over the past five years has been the considerable development of produced water infrastructure, specifically pipelines. The market is moving towards consolidation, even though progress has been slow. As produced water volumes continue to rise, pipeline infrastructure will provide more opportunities to collect volumes from multiple producers for treatment at centralized facilities with larger capacities. This largescale midstream model provides more flexibility, reliability and cost efficiencies, making this approach a more economical and sustainable option, especially in the face of rising freshwater prices. New/innovative water treatment technologies now can operate within a larger functional window and handle upset scenarios with varying feed qualities without compromising outlet quality. These new technologies also simplify overall plant design by removing multiple pieces of equipment and increasing process efficiencies. In addition, automation and remote monitoring technologies reduce overall operating expenditures, particularly due to labor and chemical savings. The Produced Water Society recently released a suggested outlet target quality guideline, a step in the right direction to address the challenges in standardization of outlet water requirements when sharing treated water amongst operators.
ECONOMICS AND SCALABILITY
Exterran recently completed a study for a produced water reinjection project that compared a traditional water treatment plant design to an innovative large-scale design scheme for a 750,000 BPD facility. The traditional design approach includes multiple trains of degasser vessels, skimmers, induced gas flotation (IGF) vessels and filter polishing to reduce oil in water and suspended solids.
