Oxidation mechanisms of metallic carrier materials for gas separation membranes in power generation systems with carbon dioxide capture

假设进一步减少核电，并在通过广泛使用可再生能源提供能源之前，唯一可用的桥梁技术可以由传统发电厂提供。二氧化碳捕获和储存(CCS)技术可以抵消二氧化碳排放量的增加。实现这一技术目标的最有效途径是引入使用陶瓷膜技术的气体分离技术。然而，到目前为止，几乎没有任何关于开发用于气体分离系统组装的金属支撑结构的研究。金属载体必须在温度高达1000°C的不同浓度的O2、N2、H2、H2O、CO2和CO的使用环境中具有高耐腐蚀性。本项目旨在研究在这种复杂的使用环境中氧化机理的基本方面。根据工艺要求，研究的合金将是以NiCrAl或NiCoCrAl合金为基础的氧化铝成形材料。用于研究混合气体环境中氧化过程的实验方法包括使用稳定的气态示踪剂18O2、H_(18)O、C_(18)O和使用色层进行原位气相分析。采用各种分析手段，特别是常规和高分辨率的透射电子显微镜，研究了块体合金在不同长度尺度上的结垢机制和微观组织变化。在双边方法中获得的基本知识将用于开发新的和改进的合金概念。

Assuming a further decrease of nuclear power and before energy supply by extensive use of renew-able sources is available, the only available bridging technology can be provided by conventional power plants. The undesired increase in CO2 emissions can be counteracted by carbon dioxide capture and storage (CCS) technologies.The most efficient way to reach this technological goal is by introducing gas separation techniques using ceramic membrane technology. However, until now hardly any investigations have been carried out on the development of metallic support structures for the assembly of the gas separation systems. The metallic carriers must possess high corrosion resistance in service environments with varying concentrations of O2, N2, H2, H2O, CO2 and CO at temperatures up to 1000°C. The present project aims at an investigation of the fundamental aspects of the oxidation mechanism in such complex service environments. Based on the technological requirements, the alloys to be studied will be alumina forming materials, mainly on the basis of NiCrAl or NiCoCrAl alloys. The experimental methods used to study the oxidation processes in the mixed gas environments include the use of stable gaseous tracers such as 18O2, H218O, C18O2 and in-situ gas phase analysis using chromatography. Various analysis methods, especially conventional and high resolution TEM will be employed to investigate the scale formation mechanisms and microstructural changes in the bulk alloy on various length scales. Basic knowledge gained in the bilateral approach will be used to develop new and improved alloy concepts.