Research progress of uranium in coal and its migration behavior during coal combustion

in order to stody the ocurence of uranum in coal and ash.and to reduce the release of radioactive mater al during the process of coal uliization.,the research ituation of uranium in coal as bee reviewed in ths paper.which including the conents distrbuton.,mode of ocurence and leaching characeistios of uraniumin coal and ash.as wol as enrchment characterstics during cal combustion and the enwironmenaleicts are detaled.Theresuis show that uranium concentration inChinese coal in overll lose to the word average ,and mainl in organic matters( even as high as 70%90% in some samples ,Uraniumn usall enmi hed in ine parit esof fy ash during coal combustion.Finally.the migration and 'ransformation mechanism of uranium during cal combusion is discusse in this pape: and put forwards reserch orientation and emphasis.