For more than 50 years, Dow Water & Process Solutions has been a leading supplier of advanced water purification and separation technologies. Water and water quality are critical to improve the recovery and minimise the environmental impact of hydrocarbon production.
As oil and gas resources become more difficult to reach, produce and treat, Dow offers advanced chemistry and technology solutions to help drive new production from conventional and unconventional sources. Dow helps maximise customer value by offering innovative, customised solutions to resolve some of the market’s most pressing challenges, such as maximising supply, improving efficiencies and enhancing regulatory compliance.
Dow offers multiple water technologies to address the unique water resource management needs of the hydrocarbon exploration and production industry. DOW FILMTEC™ reverse osmosis, nanofiltration membranes and Dow ion exchange products offer complete or tailored removal of ionic contaminants from source waters for injection, or produced waters for discharge. The TEQUATIC™ PLUS fine particle filter is a new, innovative technology, designed to filter difficult-to-treat oilfield waters with high total suspended solids. And our portfolio of ADSORBSIA™ adsorbent media, specialty resins, and DOW ultrafiltration (UF) membranes offer complementary tools to increase the performance of oilfield water systems.
Injection water treatment for enhanced oil recovery
Seawater flooding is a widely practiced secondary enhanced oil recovery process. It is critical to remove sulfates from this water to maintain formation permeability by avoiding reservoir scaling and souring. The use of membranes notably reduces the amount of chemicals, such as nitrates, required for souring prevention and remediation. DOW FILMTEC SR90 nanofiltration membranes are an industry standard for removing sulfates from injection water in oilfield operations. UF membranes offer high-quality feedwater, practically free of fine particles, colloidal matter and bacteria, resulting in higher production rates, with lower weight and smaller floorprint requirements compared with conventional treatment schemes.
Water chemistry has a profound impact on the effectiveness of tertiary enhanced oil recovery techniques. Salinity and water composition must be compatible with the formations to optimise wetability and maximise recovery of original oil in place. Additionally, water chemistry impacts the use of alkaline agents and surfactants used for controlling surface tension, and polymers used to modify viscosity.
DOW FILMTEC reverse osmosis and nanofiltration elements help tailor the salinity of injection water to the formations into which they are injected. Additionally, these elements offer particulate-free water to help maintain permeability in enhanced oil recovery schemes.
Produced water treatment from thermally enhanced oil recovery processes
Low-pressure steam is injected into formations to reduce viscosity and improve oil recovery for heavy oils and bitumen. Water treatment is required to protect the boilers and once-through steam generators, and for discharge of produced waters. Dow offers a selection of premium cation-exchange resins and packed bed technologies to offer high-efficiency, high-temperature ion exchange softening.
When make-up water originates from brackish sources, DOW ultrafiltration and DOW FILMTEC RO membranes are industry leaders.
Dow also manufactures a number of specialty contaminate resins based on stringent discharge requirements for heavy metals, NORM and BTEX.
Produced water treatment from coal seam gas (coal bed methane) production
The methane found in coal seams can be a valuable unconventional gas source. To extract it, shallow water wells are drilled over coal seams and water is pumped out of the formation until the hydrostatic pressure on the formation is reduced enough to allow the gas to escape. In many cases, this water is too high in total dissolved solids or sodium absorption ratio for direct discharge and must be treated.
Dow is the only component supplier to offer ultrafiltration, reverse osmosis and ion exchange components – DOWEX™ ion exchange resins and DOW FILMTEC reverse osmosis elements – for a complete solution to treat waters produced by the extraction of coal seam gas.
Produced water treatment from shale gas and oil production
Dow offers a wide range of water treatment technologies, combined with the technical expertise to treat the water produced by shale gas or oil extraction via hydraulic fracturing techniques. The organic compounds used to optimise formation fracture often require treatment prior to reuse or discharge. Dow’s ion exchange and DOWEX OPTIPORE polymeric adsorbent technologies facilitate the reuse of flow back and produced waters by removing harmful metals and organic compounds, such as BTEX. Additionally, deep gas seams are often associated with hyper-saline, deep aquifers which generate hyper-saline formation water.
DOW FILMTEC reverse osmosis and nanofiltration elements can be used to manage shale gas-produced water. And the TEQUATIC™ PLUS fine particle filter, an innovative new technology, can be used to help filter difficult-to-treat waters with high total suspended solids.
The TEQUATIC PLUS filter is proving successful in applications such as produced water disposal wells by reducing the maintenance and consumables costs compared to traditional technologies such as cartridge and bag filters.