P-38

Macronutrients such as Phosphorus are essential for all forms of life. Due to the unsustainable way of consumption of this irreplaceable and finite resource new technologies for its extraction are being researched and developed to cope with the demand in a more sustainable way. Despite the lack of phosphate rock deposits in Europe there are important sources of phosphates such as manure from intensive livestock production, in the eastern areas of the Netherlands this secondary source of phosphates should be taken advantage off to extract the minerals contained in it. Due to European and Dutch environmental regulations manure has to be processed, this is mostly performed by anaerobic digestion resulting in a digestate rich in minerals and methane.

The contribution of this PDEng project to the overall Mineralen Terughalen project will be the development of an economically feasible solid/liquid separation technique for the digestate, separation of phosphate with a solid fraction of at least 28% in dry matter and a liquid fraction that will contain < 5% of TS. The main goal of this PDEng project is to optimize the separation of phosphate. It is necessary to minimize concentration of suspended solids in the liquid fraction to separate the phosphate in a concentrated form. In order to minimize the concentration of suspended solids a solid/liquid separation must be performed, the separation of these two fractions can be performed by several mechanical and chemical techniques or the combination of two techniques that will be researched during the PDEng project. The addition of flocculants can improve the separation process obtaining better results, different flocculants will be researched to determine the best option for the project.