05.03.2014| Potsdam: Scientists at the GFZ German Research Centre for Geosciences and  industry partners have developed a mobile bypass system to investigate the impact of temperature-dependent microbial processes in geothermal plants. Based on a modular concept the bypass can be adapted to site-specific conditions and equipped with different material samples. The focus is on the influence of microbial metabolism on precipitation, scaling and corrosion at different temperature levels to develop effective measures for the mitigation of microbiologically influenced disturbances. The system is currently installed at a geothermal plant in Neubrandenburg, 200 km north of Berlin.

To date, about 240 MW thermal power and 25 MW electrical power are provided by deep geothermal plants in Germany. Operating experience shows that processes such as corrosion and scaling can have a huge impact on the reliability and the economic efficiency of geothermal plants. Despite extreme conditions like high salinity and temperature of the fluids, microbial metabolism can accelerate these processes. The above ground installations and also the borehole, borehole-near areas and even the reservoir can be affected or damaged. For instance, electrical submersible pumps are commonly used in geothermal facilities. The high temperature and the limited space require very expensive designs. Consequently, pump failures due to corrosion can lead to severe financial strains for the operator.

The researchers around the biologist Hilke Würdemann will develop counter-measures to influence these microbial induced process failures. The research activities are conducted in the framework of the BMU funded project MiProTherm.