The objective of this thesis is to test the possibilities of recovering ammonium from sludge liquor within the project “GreenAmmoniaFUEL”. The recovered ammonium is accumulated in a regeneration solution. First of all ammonium is separated using zeolite as an ion exchanger (clinoptilolite). For regeneration a sodic-containing solution is used in which ammonium accumulates. The further processing of this regeneration solution can be done by vacuum membrane distillation to produce ammonia for fuel cells.
An existing experimental plant is used to perform the related experiment. The water and zeolite ratio are varied in the experiments and the effect of adding increasing amounts of sodium chloride to the regeneration solution is analysed. NaCL-addition affects the equilibrium concentration of the solution.
Results proof that a large part of the separated ammonium from the sludge liquor can be found in the regeneration solution. During the regeneration an equilibrium is reached between NH4+ on the zeolite and in the regeneration solution. The ammonium concentration reaches a peak concentration of approx. 520 mg L-1 without NaCl-addition. If sodium chloride is added (the corresponding concentrations of sodium are 4,25 g L-1, 8,5 g L-1 und 17 g L-1), the concentration of ammonium accumulated in the solution increases up to approximately 2200 mg L-1.