Extracting Salt to Heal Wounds
May 16, 2011
The Jewish Exponent — Amer Sweity got a lot of flack when he told friends and family he was leaving Jordan to study water desalination at Ben-Gurion University of the Negev.
He still remembers his parents’ response: “You couldn’t find a different place?”
“Being here is like a big compromise — one of the biggest compromises I have made in my life,” said Sweity, 30, of Amman. “I have plenty of friends who cut me off.”
Some call him a traitor, he said, but they don’t understand that “water’s not just an Israeli conflict.”
He sees the solution in science, and the closest place for him to be at the forefront of that research is across the border in Israel, where scientists have been experimenting with various ways to desalinate water for more than 40 years.
Here, in the middle of Israel’s expansive Negev Desert, researchers in multiple fields have been working on new technologies to make the most of every drop of precious water.
This summer, they’ll test a new purification system in Sweity’s native Jordan. The plant, which will be installed in partnership with the Hashemite University of Jordan near Al-Zarqa, northeast of Amman, is expected to produce about 120 cubic meters, or 31,000 gallons, of clean water per day.
That’s not a lot, “but if you’re in a place that’s water-stressed, it could help,” said Jack Gilron, a professor at Ben-Gurion’s Zuckerberg Institute for Water Research.
Issue Brewing Since the ’60s
Jordan’s crisis isn’t as bad as, say, Bangladesh or parts of Africa, where there’s no running water, or the water that is there is loaded with parasites or pathogens, said Gilron, 59.
Still, it’s among the countries considered to have the scarcest water supplies in the world. Small villages rely on wadis polluted by untreated sewage. Some days, water doesn’t flow to parts of Amman, the nation’s capital.
During the summertime, Sweity remembered, each neighborhood would be assigned a certain day to collect water, usually once a week or sometimes once every other week. His family was allowed to fill a 20 cubic meter reservoir, which had to last them until the next scheduled water distribution.
It’s an issue that’s been brewing since the 1960s, he said.
At that time, according to Sweity, Jordanian officials didn’t even have a master plan for the water supply.
Imminent shortages became apparent as the population swelled — first from an influx of Palestinians after the Six-Day War in 1967, and then from Iraqi refugees after the Persian Gulf War of 1990-91. While Jordan has a small border on the Red Sea, the government hasn’t had the funding to build a desalination plant there, said Sweity.
Israel gets roughly one-fifth of its water from desalination. With two more major plants scheduled to open in the coming years, that figure will increase to almost a third, reducing the burden on overused fresh water supplies in the Sea of Galilee and ground aquifers in northern Israel.
Most of that desalinated water currently comes from three large coastal plants, though several smaller facilities also convert inland brackish supplies.
Without getting deep into scientific detail, the brackish-water plants separate brine from the water by pumping the pressurized liquid across a series of synthetic membranes. Currently, the plants recover 75 percent to 85 percent of the water, according to Gilron.
Gilron has developed a way to extract up to 90 percent by reversing the direction of the water flow just before the concentrated brine gets to a state where minerals build up on the membrane. An ultrasonic sensor, which is being developed by the University of Colorado, detects when to reverse the flow, he explained.
The more “sweet” water that’s extracted, the less concentrated brine is left over to dispose. That’s crucial for inland countries like Jordan, where condensed leftovers can’t be diluted back into the sea. They can’t just be dumped on the ground, either, because the high concentration of salt would contaminate the soil, potentially killing plants and polluting groundwater supplies, said Gilron.
To ensure that doesn’t happen, the brine must be either repurposed into a commercial product or carefully sealed in impermeable double-lined evaporation ponds, said Gilron. One such pond takes up about 40 acres in the far western Negev. Solids collected from another pond in Eilat are used to make table salt. In either case, explained Gilron, the additional step can double the cost of the entire process compared to desalination plants that have the benefit of returning briny leftovers back into the sea.
Increasing the amount of recovered water with the new reverse flow system, however, has the potential to reduce overall costs by about 20 percent, Gilron continued. In dollars, it would cost roughly 36 cents per cubic meter, down from about 45 cents. For a modest-sized plant processing 10,000 cubic meters a day, he said, that adds up to nearly $330,000 in savings per year.
Recognizing the potential business opportunity, Gilron has already set up a company to commercialize the technology called ROTEC, short for Reverse Osmosis Technologies. Though the flow-reversal pilot in Eilat just got going in February, the government of Israel recently awarded the company another grant to retrofit a larger brackish-water desalination plant that can produce 1,200 cubic meters a day.
Small Steps First
The response has been slower — and more muted — in Jordan, where the second pilot plant is expected to open in June or July.
Even though major international cooperatives like the NATO Science for Peace program and the Middle East Desalination Research Center have provided much of the nearly $1 million budget for the project, there are still political tensions to surmount.
Gilron said his counterparts in Jordan have already come under fire for sending the “wrong” political statement by associating with an Israeli institution.
Because of such anti-Israel sentiment, he said, “we have to do it in a very modest way, not beating our drums but just quietly going in, starting to help with this.”
So why even bother if the animosity runs so high?
“It’s too important,” said Gilron. By giving others in the region the tools to reduce water scarcity, “we reduce the pressure on all of us.”
The fact that Jordanians, Palestinians and Israelis have managed to cooperate on water issues thus far has been a bright spot amid the conflict, said Gilron.
“Everyone has made a very clear decision that we’re not going to let the other politics in the region interfere,” he said.
A few months ago, at another Ben-Gurion project in the West Bank, for example, university colleagues started a reverse osmosis process to clean harmful organic waste from reclaimed water in Nablus that will be reused for agriculture. The project, funded by USAID, has been in the works for five years, according to Gilron.
Perhaps with more successes on small projects like these, he said, scientists can push for bigger ones.
While Sweity isn’t directly involved with the pilot plant in Jordan, he said his goal is to use the connections he’s making in Israel to bring similar, large-scale plants to his country after completing his master’s degree. He dreams of working on the proposed Peace Conduit, a massive pipeline that would siphon water from the Red Sea to replenish the receding Dead Sea, with major desalination plants along the way.
“If you don’t have that kind of project, that means people will suffer, and by increasing the suffering of the people, the worst scenario will face this region,” he said. Reducing the water stress “won’t only make peace with the Palestinians, it will solve issues with all Arab nations.”
On a personal level, Sweity said living among Israelis has helped him understand their approach to life and the political conflict.
“It’s almost like the middle of nowhere, so you have no other choices for who to hang out with,” quipped Sweity. “It’s brought to my mind that we are all human.”
“There’s no trust at all between our leaders,” Sweity said, “but the scientists, they trust.”
Deborah Hirsch was one of seven journalists invited to participate in the Sixth Annual Murray Fromson Media Mission to Ben-Gurion University, sponsored and hosted by the American Associates of Ben-Gurion University of the Negev.