Research areas and projects

The collaborative project Clean Circles comprises four interconnected and closely coupled research areas, to each of which several projects are assigned.

Overview of projects

Research areas

1 Reduction Processes

Renewable Energy Storage by Reduction of Iron Oxides: Investigation of new innovative iron oxide reduction processes based on electrolysis (electrochemical) and in fluidized beds with green hydrogen (thermochemical).

Learn more

2 Oxidation Processes

Renewable Energy Release by Iron Oxidation: Investigation of oxidation processes (thermochemical) of iron and iron oxide particles at different oxidation levels under a wide variety of process conditions.

Learn more

3 Thermodynamic-mathematical Analysis

Thermodynamic-mathematical and Techno-economic Analysis of Iron Cycles: Mathematical models of the entire iron cycle for energetic, exergetic and exergoeconomic analysis as well as optimization and evaluation of scenarios. Coordination with Research Area 4 on economic and political boundary conditions.

Learn more

4 Socio-economic Modelling

Governing of Innovations and Socio-economic Modelling: Strategies for political sector coupling and analysis of innovation processes. Identification of funding schemes in energy, structural and mirgation policy to establish new technologies based on the model from research area 3.

Learn more

Projects sortable by research area

Project title (PI) Reduction Processes Oxidation Processes Thermodynamic-mathematical Analysis Socio-economic Modelling
Experimental investigation of iron and iron oxide particle clouds during thermo-chemical oxidation and reduction (B. Böhm) x x
Development of a kinetic model based on experimental investigations of the thermochemical reduction/oxidation of iron oxide/iron (O. Deutschmann) x x
Thermochemical reduction/oxidation in fluidized beds (B. Epple) x x
Dissolution and electrochemistry of iron oxides in ionic liquids and deep eutectic solvents (B. Etzold) x
Modeling and numerical investigations of nanoparticle formation during oxidation of iron particles (F. Ferraro) x
DNS-Analyse der Clusterbildung und der Verbrennung von Eisenpartikeln in homogener isotroper Turbulenz (B. Frohnapfel) x
None-intrusive, time-resolved diagnostics of iron based micro particles undergoing thermo-chemical reduction or oxidation (D. Geyer) x x
In situ and operando hard X-ray studies on iron and iron oxide microparticles undergoing reduction or oxidation (Grunwaldt) x x
Dissolution and motion dynamics of metallic microparticles in ionic shear flows (J. Hussong) x
Influence of oxidation and reduction conditions on iron signatures as followed by Mössbauer spectroscopy (U. Kramm) x x
Structure-property relationships of iron particles and its oxides (H. Nirschl) x x
Phase-field modeling of phase transformation, intra-particle diffusion, microstructure evolution of iron oxide (D. Raabe) x
Kinetic model development for iron particle thermo-chemical reduction/oxidation and investigations of dust firing in CFD simulations (U. Riedel) x x
Modeling of the reaction-transport coupling for single, iron-based microparticles undergoing thermo-chemical reduction or oxidation (A. Scholtissek) x x
Evaluation of iron particle combustion in shear-driven turbulence using carrier-phase DNS (O. Stein) x
Investigations of the reduction of iron oxides using density functional theory calculations (F. Studt) x
Experimental investigation of thermochemical oxidation of iron particle combustion under laminar and turbulent flow conditions (A. Dreizler) x
Numerical investigation of laminar and turbulent iron dust/air combustion (C. Hasse) x
Laminar combustion wave velocity and structure investigation in Bunsen type iron dust burners (D. Trimis) x
Influence of turbulence on flame propagation in iron dust suspensions (N. Zarzalis) x
Multi-criteria systems analysis (P. Stephan) x
Scale- and complexity-reduced models for reduction and oxidation based on reactor networks (D. Bothe/S. Hartl) x
Mixed-integer nonlinear optimization methods for the optimization of the overall system Clean Circle under uncertainty (S. Ulbrich) x
Robust optimization and evaluation of the energy and logistics networks in Clean Circles (M. Pfetsch) x
Governance of sector coupling (M. Knodt) x
External governance of sector coupling (A. Niemann) x
Innovation economics (I. Ott) x
Junior Research Group Integrated Systems Analysis (K. Schulze) x x
Energy system analysis (W. Fichtner) x x
Dynamics between issue publics and mainstream media regarding debates about clean energy transition (S. Post) x
Inter- and transnational governance initiatives for clean energy (J. Tosun) x

Cooperation with the GIZ (German Corporation for International Cooperation)

The GIZ advises on energy policy issues worldwide, with a particular focus on renewable energies, and can draw on years of contacts in Morocco and its own office in Rabat. The findings of Clean Circles are to be discussed and evaluated with GIZ.

Learn more

LandesEnergieAgentur Hessen and Extremadura Energy Agency (Spain)

The LandesEnergieAgentur Hessen will support Clean Circles together with the Extremadura Energy Agency (Spain) in assessing the transfer potential in Spain. Not least through the joint EU project FIRESPOL, both have experience in the acquisition and use of EU structural funds.

Learn more

DLR Institute of Low-Carbon Industrial Processes

One focus of the cooperation witht the DLR is the direct reduction of iron oxide with synthesis gas and pure hydrogen, for example in the steel industry. The knowledge gained in Clean Circles will contribute to scaling up more accurately: from laboratory to real plant sizes.

Learn more