Prevention of freshwater eutrophication through phosphorus recovery via manipulation of iron and phosphorus interactions
In freshwater bodies excess phosphorus often leads to eutrophication and in the worst case to (toxic) algae blooms. Often binding agents (phosplock, iron salts, alum) are added to the lake to bind the phosphate in the lake sediments. A disadvantage of this approach is that the phosphate is bound but still accumulates in the lake sediment and therefore there is a risk that it may be released again if conditions change. Phosphorus is a precious resource and therefore removal and recovery would be a more sustainable approach. In this project we will develop strategies using the affinity of phosphate to iron as a basis for binding and recovery of the phosphate from surface water.
The project will evaluate two possible routes to achieve the above objective. One possible route is is to apply ironoxide based adsorbents either in the sediment itself or on selected water layers in the lake to absorb phosphorus on the adsorbent. After saturation of the adsorbent the phosphorus can be recovered via regeneration of the adsorbent. Research questions are material science aspects to design innovative ironoxide coated adsorbent structures (grids, beads, tubes) with high capacity for P-adsorption that can be easily submerged in lake sediments and taken out again for regeneration and P-recovery. Other research questions are related to effects of competing ions like humic acids on the adsorption capacity and the regenerability of the adsorbent. A second route that we will investigate is to dose ferrous iron into lake sediments to stimulate bind phosphorus in the form of vivianite. Vivianite can then potentially be recovered from the sediment via magnetic separation technologies. Research questions here are the determination of the best dosing strategy (timing, depth, distribution) and possible interactions with sulphide and organic matter in the sediment.
Since this is an interdisciplinary project we are either looking for a candidate with an MSc degree in chemical or environmental engineering that also has interest in aquatic ecology or and a degree in aquatic ecology with a solid interest in (geo-)chemistry. Your social skills and curiosity make it possible for you to benefit from the multi-disciplinary environment to find creative, new approaches to the research challenge. You are able to work independently.
This project is part of a EU-financed Innovative Training Network called RecaP, and comes with two additional requirements:
These requirements are set by the EC in order to stimulate the mobility of early-stage researchers in Europe.
The PhD student will be based at Wetsus in Leeuwarden and co-supervised by TU Delft.
Promotor: Prof. Mark van Loosdrecht (Technical University Delft)
Wetsus supervisor: Dr. Leon Korving
This specific research project will be part of the Phosphate Recovery research theme where also other research projects are taking place directed towards phosphate recovery from sewage sludge and manure. Water authorities Limburg and Brabanste Delta, Vandcenter Syd, Kemira, Aquaminerals and Aquacare are the industry participants in this research theme. The project will take place in close collaboration with South Denmark University (Kasper Reitzel) and will involve a secondment for at least 2 months to this institute during the first year.
The EU project RecaP focusses on an interdisciplinary approach to the phosphorous problem. You will be part of network of 15 PhD students working on all different aspects phosphorus management in different EU countries. The RecaP project includes several workshops, courses and secondments to one of the other research facilities and/or partners in the project. For more information about RecaP, click here.
The project will take place in close collaboration with South Denmark University (Kasper Reitzel) and will involve a secondment for at least 2 months to this institute during the first year.
For more information contact email@example.com
Wetsus, Leeuwarden, The Netherlands