The aim of a project supported by the Minister of Science and Technology is the development of a process for gas cleaning at temperatures above 1573K. The simultaneous removal of particles and alkalis should be possible with this process. This hot gas cleaning ought to be integrated into an advanced combined cycle based on a pressurized slag tap furnace. The research concerning the development of a venturi scrubber with molten slag have been done at the Institute of Ferrous Metallurgy of the Technical University of Aachen.
Studies concerning the chemical and physical properties of slags are necessary to realize such a system for hot gas cleaning. This research must be followed by research concerning the influence of physical properties of slags such as viscosity or surface tension on the atomization of liquids. Furthermore, studies are necessary concerning the precipitation efficiency of a venturi scrubber with a liquid which has the same physical properties as slag.
This paper presents thermochemical calculations with regard to the absorption of gaseous alkalis by molten slag. Furthermore, it contains the investigations concerning the influence of alkali oxides on the viscosity of moltén slag.