Low emission synthesis of titanium alloys
Within the framework of the work of the DFG Research Group FOR 1372, the project partners Institute for Processing, Landfill Engineering and Geomechanics of the TU-Clausthal (IFAD) and the Institute for Metallurgical Process Engineering and Metal Recycling of the RWTH Aachen University (IME) developed a process for the aluminothermic production of titanium-aluminium alloys with a minimum of process steps (ASH synthesis). The minimization of the process steps is based on the production and use of high-purity synthetic TiO2 concentrates by reduction of ilmenite metal agglomerates with atomic hydrogen during sulfuric acid leaching and hydrolysis under normal p-T conditions and on the mechanical activation of rutile concentrates. The use of these precursors in the aluminothermic titanium-aluminium alloy production led to a reduction of the booster demand by 30% and thus to a reduction of chlorine emissions. With this result the goal of the first phase DFG Research Unit FOR 1372 for the mentioned project partners was achieved.
In the requested second phase, the developed process is now to be transferred to the technical scale in the form of a transfer project with industrial partners. The share of IFAD together with the mechanical and plant engineering company Siebtechnik GmbH is the implementation of the mechanical activation process suitable for industrial use by modifying the eccentric vibrating cup mill used for the production of mechanically activated rutile concentrate. In addition, the production of synthetic TiO2 from the mass raw material ilmenite in a process step-minimized manner is to be investigated in terms of reaction kinetics and brought to application maturity. In this case the support of the industrial partner Siebtechnik GmbH will be provided by the centrifuge laboratory of Siebtechnik GmbH for the separation stages solid-liquid after leaching and hydrolysis. The share of the IME together with the metallurgical company Elektrowerk Weisweiler GmbH is the transfer of the developed technology to the ton scale. For this purpose, mechanically activated rutile concentrate is to be used as feedstock and heat balances are to be drawn up. In parallel, the research of low-potassium booster mixtures by mechanical activation is planned to be carried out by both project partners. Energy balances are to be drawn up for the aluminothermic system. The industrial application of the ASH synthesis is to be raised to a higher technical level by applying the vacuum inert gas technology.
- Clausthal University of Technology (TUC), Institute for Processing, Landfill Engineering and Geomechanics (IFAD)
- RWTH Aachen University (RWTH), Metallurgical Process Engineering and Metal Recycling Aachen (IME)
- Siebtechnik GmbH, Mühlheim an der Ruhr
- Elektrowerk Weisweiler GmbH, Eschweiler-Weisweiler
German Research Foundation, GZ: FR 1713