Development of impeller based ammonia recovery process with hydrodynamic cavitation and water electrolysis

Abstract

Ammonia is recently considered as an environmentally friendly carbon-neutral fuels and energy carrier capable of transporting and hydrogen. However, ammonia production consumes a significant amount of energy and emits large quantities of greenhouse gases. To address this issue, research focusing on recovering ammonia from wastewater has attracted considerable interest. Among these approaches, the ammonia stripping process is widely employed in various industries due to its simplicity and practicality. However, increasing the process scale is inevitable to enhance the efficiency of gas-liquid contact, resulting in significant energy consumption. In this thesis, I investigate the ammonia recovery process utilizing impeller to reduce the scale while achieving high recovery performance. Additionally, I develop a process that applies hydrodynamic cavitation to raise the temperature of wastewater, decompose sludge, and utilize water electrolysis to maintain the required pH conditions for ammonia recovery without adding chemical reagent.