Chování yttria při fluidním spalování uhlí

Abstract

The study elucidates the behaviour of Y at fluidised-bed coal combustion (it addresses the problem with deficiency of Y-bearing minerals by potential utilization of Y present in waste materials - coal combustiuon ashes). Real power station bottom ash and three fly ashes (from three sections of the particulate control device) were used for the preparation of 43 particle-size fractions and these samples were subjected to elemental analysis. Comparison of Y levels in the studied ashes revealed increasing Y concentration from bottom ash (43 ppm), fly ash from the 1st section (46 ppm) up to fly ashes from the 2nd and the 3rd sections (54 and 65 ppm), respectively. Evaluation of potential affinities of Y in the ash samples indicated that the most likely modes of occurrence of Y in these samples were Ti- and Zr- bearing minerals.