Recycling Water: The Transformation of Waste into Resources
Recovering valuable materials from industrial wastewater can help offset investments in circular water projects and even solve other challenges, such as reliance on fossil fuel-based energy. Industrial users can also extract value from waste by sourcing unconventional water from other sources for direct operations. This approach saves freshwater resources for potable use and can be economical for industrial users.
In recent years, KOC has intensified its effort to extract heavy oil from northern Kuwait's Lower Fars reservoir of the Ratqa oil field. Owned and operated by KOC, the Ratqa oil field is the first heavy oil project in the country.
The heavy oil found at Ratqa has a high viscosity and sluggish flow rate, causing KOC to require cyclic steam injection to extract the oil. This process uses approximately 300,000 barrels of water daily, which must meet specific quality standards.
With Lower Fars being among the most water-scarce regions in Kuwait, relying primarily on desalinated brackish water for industrial use, KOC would need to source the boiler feedwater from local municipalities at a premium cost. KOC sought an alternative solution to recycle and reuse all available water onsite to lower operating costs and maintain sustainable business practices in the arid region.
KOC wanted to determine the possibility of reusing reverse osmosis (RO) reject from the Sulaibiya municipal wastewater treatment and reclamation plant (WWT&RP) located 123 kilometers (or approximately 75 miles) away for clean boiler feedwater. The solution needed to be feasible in capital and operating expenditure while enabling KOC to consistently achieve its “best out of waste” sustainability goal.
WorleyParsons, the owner’s engineer, and Petrofac, the project EPC,collaborated with Aquatech to devise a process to treat the unique wastewater, which traveled from the Sulaibiya municipal WWT&RP. Due to extensive experience with recycling difficult-to-treat water, Aquatech could offer a solution that provided boiler feedwater exceeding KOC’s needs and low capital expenditure and operating costs.
The source water is challenging wastewater from Sulaibiya that contains a high scaling potential, organic contaminants, and high levels of total dissolved solids (TDS), total organic carbon (TOC), organics, and hardness. Aquatech implemented a highly water-efficient project to recover ultrafiltration (UF) and RO reject and produce high-quality boiler feedwater needed in high volumes. The UF and RO reject from the Sulaibiya municipal WWT&RP is treated with technologies such as lime softening, multi-media filtration, UF, ion exchange, high recovery RO, UV, and ozone.
Treating the water through ultrafiltration membranes removes any residual suspended solids, colloidal matter and high molecular weight organics in the feed water, achieving the low and consistent silt density index (SDI) required for RO operation. QUA’s Q-SEP ultrafiltration membranes provide superior quality and performance at a lower footprint and capital expenditure.
The subsequent high recovery RO consistently achieves 94% recovery, and the product water is subsequently treated by UV and ozone to remove any residual chemical oxygen demand (COD) and impurities. The final step of the scheme is Vacuum Degasification which is required to achieve the Oxygen limit of <100 ppb in the final product water. This project utilizes Once Through Steam Generator (OTSG) boilers to produce the steam required to inject heavy oil wells. The solution produces 3,750 GPM (5.4 MGD) of boiler feed water, which is required for steam production for operations at Lower Fars.
This water treatment plant has proven that achieving high recovery (~94%) even in an extremely challenging application is not a pipe dream but a reality and that high recovery reverse osmosis is a viable, sustainable and affordable technology that enables municipal wastewater to recycle and reuse to produce boiler feed water.
This successful commissioning of the 30 MLD wastewater recycle and reuse project for KOC’s Lower Fars oilfield represents a benchmark in sustainable water management. It has demonstrated that with sound design, including the appropriate experience, membrane technology (UF/RO) can be used to reclaim and recover every drop of water possible in a water-scarce region, thus preserving vital natural resources.
The existence of this project and approach of “recovering the wastewater from a wastewater treatment plant at scale” reduces the draw on desalinated potable water. The project offers a blueprintfor achieving a lower carbon and water footprint, as well as for new projects in a region highly affected by water scarcity.
We are proud to be part of this landmark project. Aquatech’s long-standing track record in recycling difficult-to-treat waters has resulted in a solution to reliably recover water from waste and reduce carbon and water footprint. The need to maximize the use of unconventional water resources is growing, and this is a great example of how we can utilize technology and expertise to make every drop count.
Devesh Sharma, CEO, Aquatech