Israeli Scientists Develop Method to Combat Algae Fouling at Desalination Plants

Israeli scientists have developed a novel method to remove cyanobacteria, or blue-green algae, from seawater, potentially resolving a crisis that has disrupted the operation of the country's coastal desalination plants. The concentration of these microscopic organisms, measuring about two microns, has increased significantly along Israel's Mediterranean coast since late August, causing major water supply issues.

These cyanobacteria, along with a sticky organic substance they secrete, pass through the protective screens of desalination facilities. They then accumulate on reverse osmosis membranes, impeding water flow, increasing system pressure, and reducing overall plant productivity. This fouling also necessitates more frequent chemical cleaning, leading to accelerated wear on the membranes.

Researchers from Ben-Gurion University and the Technion, in collaboration with the Zuckerberg Institute for Water Research, have achieved initial success in their purification technique. After extensive laboratory experiments, they are now testing the method at a full-scale desalination plant in Ashdod. Professor Ido Bar-Zeev reported that the treatment significantly reduced the initial high turbidity of the seawater to levels that allow the plant to function normally again.

"We conducted experiments until deep into the night. First, the tests took place in laboratories, and yesterday we moved to a full-scale experiment at the Ashdod desalination plant. Today we need to increase the volumes and evaluate the results," stated Professor Bar-Zeev. He cautioned that it is too early to declare complete success, as the method's effectiveness still needs to be confirmed. Individual treatment protocols may need to be developed for each desalination plant.

The researchers are utilizing substances already in use at the plants and are verifying that no residues remain in the water, although the additive does not reach the drinking water stage, according to the researcher. The project aims to restore the full capacity of Israel's desalination facilities, which are crucial for the nation's water supply.