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Steinau an der Straße, Germany

Kaufhold S.,BGR | Grissemann C.,LBEG | Dohrmann R.,BGR | Klinkenberg M.,Julich Research Center | Decher A.,S and B Industrial Minerals GmbH
Clays and Clay Minerals | Year: 2014

Electrical measurements are used in various fields of geoscience and technology, e.g. gas/oil exploration or landslide-barrier monitoring. Although clays are amongst the most conducting geomaterials their electrical properties are not yet fully understood. For example, in a recent high-levelradioactive- waste repository large-scale test, a bentonite barrier was monitored geoelectrically. To facilitate interpretation of the results, the reasons for the observed differences in the electrical conductivity must be understood (e.g. changes in water content, temperature, salinity of pore water, etc.). To improve understanding of the electrical properties of clay minerals, in situ measurements must be combined with laboratory measurements. In situ measurements allow the characterization of the material in its natural state and laboratory measurements, for small sample amounts, allow the user to vary relevant parameters systematically such as water content, temperature, the salinity of the pore water, or even the cation population if swelling clay minerals are present. In situ measurements using different electrode distances, from m to cm range, proved that small-scale investigations are essential because of small-scale material heterogeneities. In the laboratory, all the relevant parameters mentioned above can be controlled more easily for small sample amounts. In the present study three different small-scale devices (SSM1 - SSM3) were compared. The geometry factor, K, was determined both by calculation and by a calibration against solutions of different conductivity. Calculated and measured geometry factors were in good agreement. SSM1 and SSM2 - both with four pin-shaped electrodes - were found to be particularly applicable for in situ measurements. SSM2, with point contacts at the tips of the pins, was considered to be an improvement over SSM1 because the effects of both water content and temperature gradients (which are particularly relevant near the surface) were less pronounced using SSM2. SSM3, in which the contacts are placed at the bottom of a 4.5 mL trough, proved to be useful when systematically varying all of the parameters influencing the electrical properties in the laboratory. Source

Gorostkin S.V.,S and B Industrial Minerals GmbH | Garten V.,VGH AG
Refractories and Industrial Ceramics | Year: 2013

The quality and safety of the operation of continuous casting depend to a large extent on making the correct choices for the slag-forming mixture and the technology to use it. Automated systems developed to feed such mixtures make it possible to introduce a mixture into the mold in small and precisely measured amounts, which improves the surface quality of continuous-cast slabs, decreases the number of metal products rejected for defects of metallurgical origin, and reduces the consumption of slag-forming mixtures. © 2013 Springer Science+Business Media New York. Source

Polzin H.,TU Bergakademie Freiberg | Ranft D.,TU Bergakademie Freiberg | Tilch W.,TU Bergakademie Freiberg | Grefhorst C.,S and B Industrial Minerals GmbH | Bohnke S.,S and B Industrial Minerals GmbH
71st World Foundry Congress: Advanced Sustainable Foundry, WFC 2014 | Year: 2014

The methods for testing of moulding materials are working mostly nearly at room temperature. Examples for these testing procedures are the different green strengths or the wet tensile strength. The results of these tests we can use for control of the behaviour of the green sand moulds in the steps mouldmaking, transport and partly also pouring. For testing of properties at higher temperature (hot compression strength, residual strength⋯) we often haven't suitable testing equipment or procedures. We haven't also no informations to specific sand related casting defects from the important steps of the casting production pouring, cooling, solidification and shake out. The paper shows results of investigations in the field of high temperature deformation behaviour of ben-tonite bonded sand systems. It analyzes the strengths and the deformation of different green sand mixtures (different binders and additives) in the temperature range between room temperature and 1000°C. With the used testing equipment it's possible to show force - way - curves at different testing temperatures and to calculate the strengths. Images of the fracture behaviour of the samples give informations to the deformation and fracture type (more plastic or more brittle) of the different sand mixes. The investigations show, that the high temperature deformation behaviour and also the hot and the residual strengths are depend from the used sand mix. With these knowledge it's possible to influence the casting process, to avoid some casting defects and to have a better casting quality. Copyright 2014 World Foundry Organization. Source

Wosch E.A.T.,S and B Industrial Minerals GmbH | Hilgenhoner E.H.,S and B Industrial Minerals GmbH
Stahl und Eisen | Year: 2011

The Mouldscreen software calculates and visualizes the properties of the flux film between strand shell and mould. Displayed are all process- relevant variables, such as the shell thickness, the temperature field in the strand shell and thus the strand surface temperature, the local and integral heat flux, the heat transfer resistance in the flux film and the flux film thickness (liquid and solid), the water temperature in the cooling channels and the copperplate skin temperature as a function of posi- tion. Immediately after entering the process parameters (casting speed, water rate, mould geometry, cast- ing powder, steel analysis, etc.) the results are graphically available in different windows. Source

Taffner T.,Helmut Schmidt University | Schlegelmilch M.,TU Hamburg - Harburg | Kleeberg K.,Dr. Kim Kleeberg Umweltanalytik | Schindler S.,Leibniz University of Hanover | And 5 more authors.
Chemie-Ingenieur-Technik | Year: 2011

The odor emissions of a coffee processing company were reduced applying a fixed bed adsorber pilot plant. In order to evaluate the performance, breakthrough curves were determined using a flame ionization detector, portable electronic noses, olfactometry and analytical methods. The analytic identification of odorants and pollutants was carried out via enrichment on Tenax TA and on SPME fibers. Several odorants were identified, which determine the overall olfactory sensation. Furthermore the breakthrough behavior of different adsorbents was characterized. The olfactometric concept was applied first-time for the electronic noses. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

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