On the Development of Innovative Column Internals for Nitrogen Recovery from Agricultural Waste

Using agricultural waste as fertilizer results in contamination of groundwater, leading to environmental and health risks. A partial removal of ammonia is necessary before the waste application on fields, which can be realized via an air-stripping process. However, conventional column internals for air stripping are prone to clogging because of the high solid loads of the liquid waste. This was an impetus for the development of an innovative separator with new types of internal structures based on inclined plates. A numerical model and an experimental setup were established in our previous work and used to investigate the plates. In the present study, first, the initial packing concept was evaluated, showing promising results. Subsequently, the packing was optimized toward increasing the gas-liquid interfacial area, using both experimental and simulation-based approaches. The optimized internals prevent clogging, allowing sustainable continuous use of the column and making air stripping a more viable option for removing ammonia from liquid agricultural waste.