The proposed process based on chemical reduction of Hg2+ and subsequent re-emission of Hg0 is
characterized by lab-scale experiments. Chemical mechanisms are proposed, including SO3
2-, OH- and
uncomplexed Hg2+ as reactants. Optimum efficiency of the process is enabled by sufficient agitation and
low aeration. Process efficiency decreases with Cl-
-content. For pH 9, at least, 35 % of the total Hg2+-
inventory is stripped from the waste water per hour. The suggested low-tech process has several
advantages and could be easily implemented into existing plants. The new concentrated sink for mercury
created, increases sustainability and reduces the consumption of precipitation agents. Further experiments
will focus on heat and energy integration of the process and the utilization of slurry samples from full
scale plants. The findings could be used for further development of the proposed process as well as for the
prevention of unnoticed Hg emissions in FGD waste water treatment.