Background

Old coal mine waste dumps with high coal content tend to smoulder due to coal oxidation, and thus coal residuals ignite due to heating-up within these mining dumps. Smouldering waste dumps harm the environment (gas emissions) and require permanent safety measures often even decades after abandoning coal mines.

Smouldering coal waste dumps represent not only danger to the environment but also provide a thermal potential hitherto disregarded: so far heat and emerging flue gas discharge unused into the atmosphere.

This project focuses on analysing the thermal potential of smouldering waste dumps involving the reduction of greenhouse gases. Technical product engineering emphasises tests of extraction techniques and energetic utilization of dump heat. During scale-up phase a marketable product, ecological as well as economical advantages in comparison to waste dump security concepts will be developed as well as a field tested prototype borehole heat exchanger.

Approach

The project is subdivided into following sections:

• Basic evaluation: data acquisition by surface and drill hole temperature measurements and gas chemistry of fire pockets within the waste dump in addition to site-specific information of deposition as well as safety aspects.
• Laboratory and field experiments: analysis of influencing factors of fire behaviour on defined conditions, revision of basic approach concerning the simulation model to facilitate improvement of technical equipment in laboratory and trial test scale. 
• Numeric simulation: improvement of established model systems and development of thermodynamic models by compilation and calibration, consideration of temporal framework variations by available data files, trial tested refined numeric simulation supporting the following scale-up by evaluation of possible heat extraction and power rating and effect on long-term temperature distribution in the waste dump.
• Scale-up: concept compilation of heat extraction, thermal use and required engineered safety features given that waste dump heat features technical workability, evaluation of investment and operating expenses for utilization opportunities.
• Transfer: analysis of concept applicability to different waste dump sites in Germany, Europe as well as internationally based on technical, ecological and economical data of the investigated waste dump. The analysis will furthermore evaluate to what extend the newly-created concept contributes to sustainability of energy resources and environmental targets such as conservation of flora, fauna on old waste dumps.

Objectives

The target of project is to develop an alternative safety concept as well as an energetic concept for smouldering waste dumps. Here, technical and legal as well as ecological and economical frameworks are equally important. The project aims in a knowledge built-up on processes in smouldering coal waste dumps for safeguarding and reduction of CO₂-emissions by substitution of conventional fossil fuels. Attained results are to be applied to national and international waste dump sites.

Project partners

The interdisciplinary research association comprises of following partners:

 

DMT GmbH
DMT-Zentrum für Brandschutz und Sicherheit
Dipl.-Ing. Ulrich Hoischen
Tremoniastraße 13
44137 Dortmund
E-Mail: ulrich.hoischen [at] dmt.de
www.feuerwehrtraining.net/Seiten/welcome.html

 

 

Fraunhofer-Institut UMSICHT
Fraunhofer Institut für Umwelt-, Sicherheits- und Energietechnik (UMSICHT)
Dr.-Ing. Christian Dötsch
Osterfelder Straße 3
46047 Oberhausen
E-Mail: christian.doetsch [at] umsicht.fhg.de
www.umsicht.fhg.de

 

RWTH Aachen
Lehr- und Forschungsgebiet Kokereiwesen, Brikettierung und thermische Abfallbehandlung (KoBrA)
Dr. Christian Wirtgen
Wüllnerstraße 2
52056 Aachen
E-Mail: wirtgen [at] kobra.rwth-aachen.de
www.rwth-aachen.de/kobra

 

 

RWTH Aachen
Lehrstuhl für Geotechnik im Bauwesen und Institut für Grundbau, Bodenmechanik, Felsmechanik und Verkehrswasserbau (GiB)
Dipl.-Ing. Martin Feinendegen
Mies-van-der-Rohe-Straße 1
52074 Aachen
E-Mail: feinendegen [at] geotechnik.rwth-aachen.de
www.geotechnik.rwth-aachen.de 

 

 

aix-o-therm GeoEnergien
Dr. Roland Gaschnitz
Beginenstr. 7
52062 Aachen
E-Mail: gaschnitz [at] aixotherm.de
www.aixotherm.de 

 

Contact 

Dr. Roland Gaschnitz
aix-o-therm GeoEnergien
Beginenstr. 7
52062 Aachen

Tel.: +49 241-4017865
Fax: +49 241-8092624
E-Mail: gaschnitz [at] aixotherm.de
Internet: www.aixotherm.de