Samenvatting

Around 60% of drinking water in the Netherlands is from groundwater, often containing high concentrations of dissolved iron. This is generally removed by aeration, which is an important process in both drinking- and waste water treatment. The known disadvantages are high energy consumption relative to the aeration capacity and being prone to clogging. This makes aeration an expensive part of water treatment processes, accounting for 45-75% of total operational costs. This ensures that new, innovative aeration methods that are more sustainable and energy efficient are always in demand. One such innovative aeration method is the hyperbolic funnel, invented by Walter Schauberger and based on the principles of Viktor Schauberger. Walter Schauberger applied the natural phenomena of vortices for improving water quality. The hyperbolic funnel consists of a cylindrical top part and an hyperbolically shaped bottom part. The vortex formed in the funnel provides the formation of a large air-water interface compared to the liquid volume present in the system, resulting in the expectation of being a suitable system for aeration. Three different flow regimes have been identified from previous experiments, each with characteristic interfaces and aeration capacities; the Restricted Schauberger (RS), the Twisted Schauberger (TS) and the Straight Schauberger (SS). However, the actual performance in terms of aeration- and iron oxidation efficiency of the hyperbolic funnel and the possibilities for upscaling was still unknown. The evaluation of these aspects was the main objective of this research.