Innovating Water Treatment with Local Resource

Abdalrahman Alsulaili did not expect to build a research career around water. After a love for mathematics led him to a bachelor’s and master’s in civil engineering at the University of Kuwait, he received a scholarship to pursue a PhD at the University of Texas at Austin. The scholarship, however, was for environmental engineering. His resulting research on water treatment, as it turns out, propelled him toward a field of study of incalculable significance for the whole Gulf region. “Kuwait is a rich country,” Alsulaili says. “But, on the other side, it’s very, very poor in water.”

As a professor of civil engineering at Kuwait University, Alsulaili has developed a critical perspective in a profoundly arid landscape. For being one of the most water-stressed nations in the world, Kuwait certainly does not act like it: the country’s per-capita water consumption regularly ranks as one of the highest in the world, imbibing more than four hundred liters of water per day. Approximately three-fifths of this supply flows out of a network of less than a dozen desalination plants. Another one-fifth is tapped from the region’s scarce and depleting groundwater, which is often so brackish that it must be mixed with the desalinated supply, or used for non-drinking purposes such as irrigation or construction.

The remaining one-fifth, or 20%, of Kuwait’s water resources derive from treated wastewater (which actually makes Kuwait—along with other modestly-sized, water-scarce countries such as Qatar and Singapore—something of a world leader). This success, however, may prove insufficient for the coming resource crunch: current projections suggest that, by 2050, the entire Gulf region may lose as much as half of its water availability per capita, falling vastly short of its future needs.

Alsulaili, however, has recently completed a project funded by the Kuwait Foundation for the Advancement of Sciences (KFAS), which may provide a creative tactic to help address this looming shortfall. His final report, “Utilization of Dates Seeds as Waste Material in The Treatment of Wastewaters,” investigated the potential of the humble date—750,000 tons of dates are consumed in Kuwait each year—as a natural, affordable form of wastewater bio-filter.

This is hardly the first attempt by engineers to find a productive use for agricultural waste. Waste management is currently enjoying a research heyday, as every municipality on earth seeks out ways to wrest a little profit out of their waste stream (while also reducing the growing burden of land-intensive, unsanitary landfills). Prior to his most recent publication, Alsulaili had authored a conference paper titled, “Agricultural Waste-Based Biochar as a Low-Cost Sorbent for Water Treatment,” which investigated the potential of not just date seeds, but banana peels, Rhamnus seeds, and coffee residue.

“But when I read the literature, one thing that got my attention is that they talked about date seeds as if they’re all the same,” Alsulaili says. “But if you visit us in Kuwait, there are different types! Big, small, sweet—and so, when we talk about the activated carbon we can produce, are all these seeds the same or not? This is the idea in my head.”
Alsulaili’s hypothesis, as it turned out, proved especially fruitful. Along with his co-authors Abdelrahman Refaie (also of Kuwait University) and Hector Garcia (of the IHE Delft Institute for Water Education, in the Netherlands), Alsulaili tested an impressive spread of nine distinct date varieties. After selecting smaller seeds to undergo the process (with diameters from 0.3 to 0.85mm), the researchers thoroughly rinsed and dried the dates for twenty-four hours to prepare them for “activation”—a treatment process that would fill the seeds with small, porous holes. This treatment exponentially increases the activated object’s surface area by giving it a microscopic “sponge”-like structure to which molecules can adhere.

While each variety, theoretically, did prove to be capable as a substitute for activated carbon, the most potent varieties proved to be as much as seven or eight times as effective than others; the Khalas and Khodari varieties, for example, activated especially successfully. But while the Khodari variety exhibited an especially porous structure, the Khalas variety ultimately emerged on top: Khalas pores—by being fewer in number, but larger in diameter—proved less prone to clogging.

When all was said and done, Alsulaili found that activated Khalas seeds could attain adsorption rates as high as 71% (when compared to commercially available activated charcoal). Furthermore, the activated date seeds—a waste product that would otherwise wind up in Kuwait landfills—could be produced at 55% less expense. These figures, meanwhile, represent early results, achieved with the finite resources available to Alsulaili’s laboratory; if activated date seeds are appropriately commercialized and produced at scale, they might exhibit even higher rates and more economical production costs.

Activated date seeds may also find utility when applied to a major by-product of the Kuwaiti oil industry: a mixture of oil, water, and suspended solids known as “produced water.” This water cannot be remediated for public use—its high salinity renders it unsuitable even for irrigation. Alsulaili investigated whether activated date seeds could facilitate the filtration of produced water in such a manner that it can be re-injected into Kuwaiti oil wells.

In October 2023, Alsulaili served as chair of the Kuwait University’s First GCC Engineering Symposium, in the hopes of bringing together his fellow researchers to address these pressing challenges. “Kuwait, Qatar, Saudi Arabia: we all have the same problems!” Alsulaili says. “We have the same culture, we have the same challenges. Maybe the same problem I work on here in Kuwait, another group is working on in Qatar. Why must we duplicate ourselves? We should unify our efforts.”

“This is what I love about environmental engineering,” Alsulaili says. “Yes, you can build some buildings, or increase the strength of concrete or steel. But if you create good for the environment? You can affect everyone’s lives.”