Micropollutants and pathogens can enter soil and water from various sources. For example, household wastewater contains a wide range of contaminants, including pharmaceuticals, hormone residues, personal care products and pathogens. Similarly, micropollutants such as pesticides, or pathogens from manure application can also discharge directly into surface water.
In this research theme we aim to remove micropollutants and pathogens from soil and water by using biological cleaning methods, supplemented by physical and chemical technologies.
Wastewater treatment plants are not designed to remove micropollutants and pathogens and pathogens sufficiently, they enter surface waters, affecting the aquatic ecosystem. For example, the presence of estrogen-related compounds has been associated with feminization of fish, while antibiotic residues may lead to antibiotic resistance in microorganisms. If these waters are used to produce drinking water, the elimination of these micropollutants is even more important and poses additional challenges.
Therefore, in ETE’s Reusable Water Theme several research projects focus on the removal of these contaminants during wastewater treatment to obtain clean effluent as well as drinking water production, to obtain clean drinking water.
Numerous physical or chemical treatment technologies for the removal of micropollutants are currently available, like oxidation and membrane technologies. At ETE, we focus on developing novel technologies that are more effective, have lower costs, and have smaller energy requirements in order to fit the needs of the water and soil sectors.
We apply three major water treatment technologies:
- Constructed wetlands. These man-made, natural-looking, wetlands originally used for the removal of nutrients can be adapted for the removal of micropollutants through natural processes, like sorption to soil, microbial degradation, uptake and transformation by plants, and light (UV) degradation. Continuing research focuses on a better understanding of different removal pathways to optimize and improve the system.
- Natural biofilms Biofilms are densely-packed microorganisms, that grow naturally on different surfaces and may degrade micropollutants. ETEs research focuses on their possible role in micropollutant removal in wastewater treatment and drinking water production. Current research is aimed to better understand the environmental conditions favoring specific bacterial communities for optimal micropollutant degradation in:
- Groundwater biofilms to remove micropollutants prior to drinking water production.
- Filtration systems in drinking water treatment plants containing either biofilm-coated sand or activated carbon.
- Combined treatment technologies. ETE aims at novel combinations of physical, chemical and biological treatment processes to develop technologies suited to degrade micropollutants.