Solutions for the reduction of micropollutants from wastewater
Conventional biological as well as mechanical wastewater treatment methods are not sufficient for reduction of micropollutants. The objectives with traditional wastewater treatment is to remove degradable organic matter, nitrogen and phosphorus. By implementing advanced water treatment technologies the problem with micropollutants can be solved.
There are several available technologies that has been proven to work. According to Rik I. L. Eggen et al (Reducing the Discharge of Micropollutants in the Aquatic Environment: The benefits of upgrading wastewater treatment plants) the large scale studies that preceded the Swiss decision suggest that ozonation and powdered activated carbon (PAC) are the technically most feasible methods. Both methods, according to the above article, reduces the load of broad range micro pollutants with over 80% and should be followed by a polishing step such as sand filtration to eliminate any bioavailable oxidation products and particles.
The cost aspect is also important and in Switzerland they experience the cost to be more or less the same for these two technologies. Studies in Sweden suggests differently (Läkemedelsrester i Stockholms vattenmiljö. Cajsa Wahlberg et al). They have found that the cost for ozone treatment is 50% lower than the cost for PAC treatment.
Read more about the cost of using ozone for reduction of micropollutants and download the COST COMPARISON for different treatment methods adapted from the above study.