Produced water is an inextricable part of the oil- and gas-recovery process, and it is by far the largest-volume waste stream associated with oil and gas recovery. More than 20 billion bbl of water is produced each year in the United States, and more than 90 billion bbl of water is produced annually worldwide. The management of these large volumes of water is an increasing challenge for the oil and gas industry, not only from a technical and economical point of view but also for all environmental issues related to its management. A substantial part of these volumes is directly reinjected into hydrocarbon reservoirs to maintain reservoir pressure and to displace oil to producing wells. The remaining water is treated for disposal or reuse, which includes injection for enhanced oil recovery and fracture stimulation. Produced-water handling and treatment represents an estimated USD 18 billion cost to the US oil and gas industry. It is estimated that each 1% reduction in water production in the US would save USD 50 million to 100 million.
The treatment of produced water can be challenging because of variability in both quality and quantity of the produced-water stream. The quantity of produced water varies significantly over the lifetime of a field. Early on, the water-production rate can be a small fraction of the hydrocarbon-production rate, but it can increase with time to tens of times the rate of hydrocarbon produced. In terms of composition, the changes are complex and reservoir-specific because they are a function of the formation lithology, the oil and water (both in-situ and injected) chemistry, rock/fluid interactions, production type, and required additives for oil-production-related activities.
Many different types of technologies are available to treat produced water; however, the types of constituents removed by each technology and the degree of removal must be considered to identify potential treatment technologies for a given application. For some types of produced water, more than one type of treatment technology may be capable of meeting the contaminant-removal target, and a set of selection criteria must be established to narrow down multiple treatment options.
The papers featured this month deal with produced-water-treating systems, produced-water-reinjection design, and water management. I hope you enjoy reading the selected papers and will search for additional papers in the OnePetro online library.
This Month's Technical Papers
Comparing North Sea and Deepwater Gulf of Mexico Produced-Water-Treating Systems
Produced-Water-Reinjection Design and Uncertainties Assessment
Cyclic-Production-Scheme Performance Evaluated Using Reservoir Simulation
Recommended Additional Reading
OTC 24199 Water Management for EOR Applications—Sourcing, Treating, Reuse, and Recycle by Lisa Henthorne, Water Standard, et al.
SPE 165356 Water Management in Mature Oil Fields Using Preformed Particle Gels by Ali Goudarzi, The University of Texas at Austin, et al.
SPE 165693 Maximizing Flowback Reuse and Reducing Freshwater Demand: Case Studies From the Challenging Marcellus Shale by Kushal Seth, Baker Hughes, et al.
SPE 163803 Aeration and Microfiltration for Solids Removal of Produced Water From the Barnett Shale by Tor H. Palmgren, M-I Swaco, et al.
