Freisetzung und Einbindung von Schwermetallen bei der Hochtemperaturvergasung

Beside the usage of regenerative energy sources it is necessary to increase the efficiency of fossil fuel power plants to preserve these available fossil resources. As they were thermal engines, the improvement of power plants causes higher process temperatures. To protect the materials being used, like reactor walls or catalysts, at high temperatures, an improvement of gas cleaning is required. The GuD combined process using gas- and steam turbine is achieving 60% of degree of efficiency. IGCC Plant e.g. this combined process is applied with a subsequent gasification of the fuel. To minimize the unavoidable losses of energy during the gas cleaning, it is necessary to maximize the cleaning temperature. However, soption-based removal of heavy metals at high temperatures is widely less investigated than alkali or sulphur removal by sorption. The intention of this study was to determine the capability of available sulphur and alkali sorption materials for the removal of heavy metals. The examined heavy metals in this work were arsenic, cadmium, selenium, lead and zinc. The used sorbent materials were part from the groups of silicates, alumosilicates, zeolites, lime, fly ashes and some synthetic materials like titania or CaSiO3. Initially the release and the sorption behaviour were calculated with thermodynamic software. Therefore coals with different ranks and different heavy metal contents were assumed. These coals were gasified both in a fluidised bed gasifier and in an entrained flow gasifier. The results of these calculations were compared with the results of laboratory experiments at a molecular beam mass spectrometer (MBMS) to determine sorption kinetics. With a MBMS it is possible to measure the gas purity downstream the sorbent bed without condensation of the impurities. The sorption mechanisms were then investigated by XRD and SEM in additional exposure tests.

Grantor dc:publisher

Publikationsserver der RWTH Aachen University

Year dc:date

2010

Author dc:creator

• Rieß, Michael

Contributors dc:contributor

• Singheiser, Lorenz

• info:eu-repo/classification/ddc/660
• Vergasung
• Schwermetall
• Sorption
• Computersimulation
• Arsen
• Blei
• Selen
• Zink
• Cadmium
• Technische Chemie
• Heißgasreinigung
• gasification
• heavy metals
• arsenic
• selenium
• lead
• zinc

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

ger

Identifier

https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-124577%22

OAI identifier oai:identifier

oai:publications.rwth-aachen.de:63120