Research Projects
EVA-M 2.0

EVA-M 2.0

Project
Application of environmentally friendly inhibitors and CO2 in order to avoid carbonate scales in deep geothermal wells in the Bavarian molasse basin.

Sub-project Hydroisotop
Sampling and laboratory analysis, execution of efficacy tests and long term tests for inhibitor assessment, development of a standardized method for integral, process oriented assessment of inhibitors for use in geothermal.

Duration
01.06.2021 – 31.05.2024

Project partners

• Karlsruher Institut für Technologie (KIT) – Institut für Kern- und
  Energietechnik – Arbeitsgruppe Energie und Verfahrenstechnik (EVT)
• Hochschule Merseburg
• Stadtwerke München
• Geothermie Neubrandenburg GmbH

Short Description:
The formation of carbonate at power plants in the Bavarian molasse basin - especially in the circular flow of thermal water treatment - can be avoided by adding inhibitors or CO2. The treatment techniques were proven and tested in the previous project at laboratory scale and partially at industrial scale.

Within this project, two treatment techniques are going to be tested and compared with each other at industrial scale. The inhibitor NC47.1B and CO2 are going to be injected at the powerplant Dürrnhaar to compare their effectiveness under almost identical circumstances. Meanwhile, a pipe for injecting working appliance underground will be constructed and installed at Sauerlach. An inhibitor- water solution and/or CO2 can be injected underground through this pipeline.

In the next step, inhibitor and /or CO2 are being injected underground at Sauerlach and Dürrnhaar over the course of one year. An accompanying monitoring is provided to evaluate the effectivity, fitness for use, environmental safety, and economic viability.

Monitoring of the inhibitor and CO2 injection is provided through bypasses under controlled circumstances. The monitoring includes mineralogic, hydrochemical and microbial analysis.

A standardized testing and evaluating program should be developed to fulfil the requirements for a permission to inject inhibitor in the Bavarian molasse basin and to increase the number of possible inhibitors. This testing program should provide analysis of the effectivity of the inhibitor, as well as biological degradation under anaerobic circumstances at different temperatures and pressures.

Supported by BMWi, support code: 03EE4032B