RADIOLYTICAL INDUCED HYDROGEN RELEASE FROM CEMENTED WASTE FORMS

摘要

A comparison of hydrogen release rates retrieved from database has been performed in order to find out the influence of relevant parameters on the radiolytical induced gas yield. It has been shown that parameters e.g. temperature, aging time of concrete, pressure of H{sub}2 and O{sub}2, physical state of water, concentration and kind of fixation of water in concrete, dose and dose rate of radiation, radiation (α, β, γ, fragments), pH-value, concentration of inorganic salts, metals and catalysts, organic additives, ash and inorganic additives, homogeneity and composition of waste, and even experimental conditions lead to detectable changes in the gas formation rate. Values of hydrogen release from waste drums with cladding hulls of irradiated light water reactor fuel embedded in concrete and from some laboratory investigations are significantly smaller than values obtained by calculations using well established equations for hydrogen generation. The low H{sub}2-release rates are attributed in particular to nitrate from the recycling process, ironsulfide from ash additives, self adsorption of metals, catalytic effects enhancing recombination, and adsorption of hydrogen in metallic waste components.