Thomas Rinder
Research interests:
In my PhD thesis I focussed on a field scale approach on calcium carbonate formation by means of tunnel drainage clogging and precipitation in porous media, using flow through experiments.
My research objective was the identification of processes responsible for tunnel drainage scaling in each individual tunnel. Scaling might be related to water-concrete interaction, but it might also be a result of groundwater with high internal partial pressure of CO2, precipitating CaCO3 in analogy to speleothem formation. 13C/12C, Mg/Ca and Sr/Ca signatures in solids and solutions as well as leaching of potassium and sodium from tunnel wall concrete are reliable proxies to identify the responsible mechanisms. In analogy to the concept of mixing corrosion, the mixing of calcite saturated waters under alkaline conditions may lead to oversaturated solutions thus precipitating CaCO3, where redistribution of dissolved inorganic carbon (DIC) species is the crucial mechanism for whether dissolution or precipitation occurs in the mixed solution. Such a process might also be relevant for mixing of waters that derive from calcite dissolution under closed system conditions with respect to CO2, and natural environments related to the dissolution of Mg- and Ca-bearing silicates from basalt and basaltic glass.
Within the experiments for precipitation of CaCO3 in porous media I am particularly interested in trace element incorporation of divalent cations, and their effects on precipitation kinetics as well as polymorphism. The investigation of such trace element addition in order to decipher the evolution of calcium carbonate formation over time by analysis of polished thin sections is a main interest within the current position. The correlation of such 2-D methods with x-ray microtomography should be a promising approach to contribute to the understanding of carbonate precipitation in industrial processes and natural environments.
Publications:
On the colorimetric measurement of aqueous Si in the presence of organic ligands and common pH buffering agents
Rinder, Thomas ; Oelkers, Eric H.
http://minmag.geoscienceworld.org/content/78/6.toc
Appeared or available online: January 13, 2015
