from Johannes Leonhäuser, Harald von Canstein , Wolf-Dieter Deckwer and Irene Wagner-Döbler writing in Bioremediation of Mercury: Current Research and Industrial Applications:
A plant for BIOlogical MERcury Remediation (BIOMER) based on mercury resistant bacteria was operated for three years at a chlor-alkali factory in technical scale. Here we report on the performance of the plant and on the technical problems that had to be solved until a stable and continuous operation could be guaranteed. One basic improvement was the installation of a pre-treatment unit. Basic process characteristics were determined during long-term operation. The BIOMER plant could treat wastewater with up to 10 mg/L of mercury. The optimal operation temperature was between 25-35°C. A salt concentration of up to 40 g/L of chloride could be tolerated by the microbes, but the fluctuations should be as small as possible. The bioreactor has to be operated at a pH of 7.0 ± 1.0. A space velocity of up to 4 h-1 could be obtained. The wastewater flow rate should be constant to avoid export of fine particles. Finally a space time yield of 1 kg mercury per day and m3 bed volume corresponding to 100 m3 wastewater per day is possible.
Further reading: Bioremediation of Mercury: Current Research and Industrial Applications