Ozone and Dissolved Air Flotation Systems
Presentation of the problem and objective of the experiment
Parameterized HPC 3D-CFD-simulations will be used to improve an ozonation reactor that builds an additional cleaning stage in wastewater treatment plants as well as a dissolved air flotation reactor for the industry. The new EU regulation 2021 to increase the wastewater quality will lead to investment costs for additional wastewater treatment of up to 3.7 billion euros per year. Therefore, the goal is to significantly reduce investment and operational costs up to 20% Furthermore, the wastewater quality should be improved by better removing micropollutants and separating emulsified and dissolved substances
Short description of the experiment
Ozone reactors (Figure 1 left) consist of several chambers, which are flowed through in a serpentine manner. In chambers 1 and 3, gaseous ozone is injected through gas inlet plates. In the water, the ozone reacts with organic substances (DOC) and with micropollutants. The reduction of ozone is described by a reaction of the second order. The degradation efficiency of micropollutants depends on the flow pattern, the transition from the gaseous ozone to the liquid phase and the even distribution of the ozone over the total inflow. These points are significantly influenced by the geometry of the ozone reactor and the gassing plate. These are optimized iteratively to make the system more efficient. The scope of the second experiment (Figure 1 right) is a specific part of a new Hydronetik-System, called HLA-Vessel to purify wastewater containing small particles. Numerical modelling of this purely mechanical physical process covers all three physical stages: small solid particles and air bubbles dissolved in liquid. The goal of the experiment is to optimise the purification efficiency of the HLA-Vessel in terms of cycle time and purification quality.
Partner HLRS is part of the NCC Germany.