Evaluation of volatile behavior and the volatilization volume of molten salt in DIR-MCFC by the image measurement technique

点击翻译按钮获取中文摘要

The volatilization of molten salt is one of factors that control the performance of Molten Carbonate Fuel Cells (MCFC). Volatilization of molten salt promotes the cross-leakage and corrosion of metallic components. Moreover, piping blockage is caused by the solidification of volatile matter. Especially, because reforming catalysts filling the anode channel are polluted by molten salt volatile matter in Direct Internal Reforming Molten Carbonate Fuel Cells (DIR-MCFC), volatilizing of the molten salt is a weighty subject. However, neither the behavior nor the volatilization volume of molten salt volatile matter has been elucidated upon, because molten salt volatile matter that has strong alkalinity cannot be supplied directly to an analyzer, its volatilization volume is small, and analytical accuracy is poor. Therefore, an attempt was made to elucidate about the behavior of vaporized alkali hydroxide by using a non-contact image measurement technique. The DIR-MCFC electrolyte is generall … More y 62Li_2CO_3/38K_2CO_3. Consideration was given to the DIR-MCFC catalyst pollution mechanism of as follows. Molten salt volatile matter is KOH generated as water is generated when the cell reacts with electrolytes. Generated KOH returns to K_2CO_3 again in high CO_2 concentration regions, catalyst pollution being caused by the adherence of the K_2CO_3 to the catalyst. Moreover, the K_2CO_3 particle mutually coheres when generated water becomes bonding material and blockades the piping. The present report experimentally evaluates the volatilization volume of KOH, which is the behavior which changes from KOH to the K_2CO_3, particulate growth of K_2CO_3, using the image measurement technique. In measuring the KOH volatilization volume, K_2CO_3 is generated as KOH volatilized by heating it in a crucible in an electric furnace reacts with CO_2, and is then injected into a reaction tube. The amount of K_2CO_3 is measured by measuring the image of the K_2CO_3 particle with a YAG laser and CCD camera, thereby obtaining the KOH volatilization volume from the calculation of the stoichiometry of the amount of K_2CO_3. In behavior that changes from KOH to K_2CO_3, the particulate growth of K_2CO_3 can be clarified by taking a picture of a K_2CO_3 particle generated with KOH and CO_2 for an extended period. As a result, a large particle is generated with the mutual adhesion small particles, which particulate growth is accumulated, causing piping blockage. Less