LAUSANNE, Switzerland — Jan. 7, 2016 — A super-fine form of powdered activated carbon could be used by wastewater treatment plants to improve micropollutant removal, Swiss researchers have discovered, according to a press release.
Powdered activated carbon is already used in treatment plants to reduce the amount of micropollutants — trace amounts of chemical compounds from pharmaceutical or agricultural chemicals — discharged to surface waters, state the release.
However, École polytechnique fÈdÈrale de Lausanne (EPFL) reported that a super-finely ground variant of the powder captures micropollutants more rapidly than the conventional kind and has the potential to bring down the cost of treatment, noted the release. It was tested on ten representative micropollutants in the lab, and all of them were removed more efficiently — in some cases up to 65 times as fast.
The issue of micropollutants is high on the agenda in Switzerland, where authorities called for 100 wastewater treatment plants to be upgraded for enhanced micropollutant removal in response to increased concentrations in lakes and rivers, reported the release.
Ozone treatment is one method that can be effective, but when the wastewater contains certain chemicals, such as bromides, it can lead to the formation of toxic byproducts, shared the release. Treatment using powdered activated carbon avoids this problem, but is more expensive and requires more energy.
The new study, published in the journal Water Research, suggests that using super-finely ground powdered activated carbon would require less time and less carbon.
Next, the researchers will test this approach in a pilot study to make sure it is workable in a full-scale wastewater treatment plant, lead author Florence Bonvin said in the release.
You can find the entire release here.