Research Projects
HydroGeoFilt

Development of a new filter system for the application at deep geothermal plants

Duration
1^st october 2016 until 30^th September 2018

Project Partner (direct and associated)

• Technische Universität München (TUM), Lehrstuhl für Lebensmittelchemie und molekulare Sensorik, AG Wassertechnologie
• Firma Petra Hegi
• Geothermie Kirchstockach Verwaltungsgesellschaft mbH
• Stadtwerke München GmbH

Abstract
The main goal of the project is to develop an innovative, patented system for the filtration of solids from thermal water in geothermal plants. Up to now, cartridge filters, bag filters or drum filters are used in geothermal systems. In plants with a high pumping rates (> 100 l/s) cartridge filters with gap widths of 100 μm are used, which are automatically backwashed. Thereby, carbonate and iron sulphide precipitations are formed in the cartridge apertures from the inner to the outer side, which leads to a blocking of the cartridges. These effects make the normal back wash process impossible and the cartridges have to be manually removed and acidified frequently. This hinders a regular operation of geothermal power plants. The newly developed system shell work low-maintenance, efficient and economic in operation. Therefore, an innovative system will be applied and adapted on the geothermal conditions (i.e. high temperatures, high pressures, complex water composition), which has been developed and already used for the removal of solids in drinking- and wastewater. The system will be tested in pilot plant scale. Previously, modelling approaches will be done to evaluate the corrosive character of the waters for adequate materials and to calculate the flow conditions in the filter.

Division of responsibility
The procedural layout of the project including the construction and commissioning of the filtration plant at the Bayerisches Molassebecken is carried out by Hydroisotop. The aim is to establish a robust filtration of solids in a high temperature and pressure range. In contrast to conventional systems the newly developed system shall have technological, ecological as well as economic advantages.

To be able to draw conclusions under practical conditions the aim of the TUM is the mathematical simulation of the filtration process. The results shall enable the conceptualisation of the filtration systems at other geothermal locations.

Funded by Bundesministerium für Wirtschaft und Technolgie; Projektträger Jülich, funding code: 0384118A