Researchers have developed a method for cleaning industrial wastewater and recovering valuable acids used to make fertilizers.
The Ben-Gurion University of the Negev team say they can eliminate the risks posed by wastewater from phosphoric acid plants and that their method is sustainable and economically viable.
Exposure to large amounts of phosphoric acid can cause a number of health effects, including vomiting, severe abdominal pain, and even death.
The team evaluated the method with synthetic wastewater in the laboratory, with positive results. The process was successful in recovering clean water and phosphates while reducing the volume of wastewater by 90%.
The recovery of phosphoric acid is beneficial as it is the main ingredient in industrial fertilizers.
“Phosphoric acid production generates a lot of industrial wastewater that cannot be effectively treated due to its low pH and high precipitation potential,” said co-lead researcher Dr. Oded Nir.
“Today, wastewater is usually stored in evaporation ponds. However, these are prone to breaches, leaks and flooding. Just a few years ago, an environmental disaster occurred in Israel when millions of cubic meters of this acidic sewage was dumped into a stream.
“Conventional treatment processes have difficulty managing the acidity, salinity and hardness of wastewater. Therefore, we have developed an alternative three-step process for the treatment of phosphoric acid wastewater including selective electrodialysis, reverse osmosis and neutralization.
Dr Roy Bernstein, Co-Principal Investigator, said: “This process shows great promise, and we encourage industry players to examine its potential and applicability in their plants.”
Their findings were published in ACS Sustainable Chemistry and Engineering, a journal published by the American Chemical Society.