An international initiative on long-term behavior of high-level nuclear waste glass

Abstract

Nations using borosilicate glass as an immobilization material for radioactive waste have reinforced the importance of scientific collaboration to obtain a consensus on the mechanisms controlling the long-term dissolution rate of glass. This goal is deemed to be crucial for the development of reliable performance assessment models for geological disposal. The collaborating laboratories all conduct fundamental and/or applied research using modern materials science techniques. This paper briefly reviews the radioactive waste vitrification programs of the six participant nations and summarizes the current state of glass corrosion science, emphasizing the common scientific needs and justifications for on-going initiatives

Determination of the Forward Dissolution Rate for International Simple Glass in Alkaline Solutions

“…In KOH solutions, we observe a general increase of the forward dissolution rate with the increase of the pH, as previously observed in literature [1,4,[8][9][10][11][12][13][14] and especially for SON68 glass in similar tests [4]. Figure 2 shows a comparison between the forward dissolution rates obtained for the first series of data obtained for ISG and SON68 in KOH solutions: a good agreement of the results is obtained for moderately alkaline pH values.…”

“…The glass was provided by MoSCI Corporation (Rolla, MO, USA). In order to have homogeneity between samples used by the different research teams, a 50 kg batch of the ISG was produced in May 2012 and glass ingots of 500 g each were then distributed for study [1]. The nominal composition is reported in Table I.…”

“…Its composition was selected to serve as reference benchmark glass and, for this reason, it is composed of a reduced number of oxides with respect to the more complex SON68 [1,2]. The Belgian concept for geological disposal of vitrified waste foresees a 3 cm thick carbon steel overpack surrounded by a 70 cm thick Ordinary Portland cement buffer.…”

“…Similar tests were performed with the ISG. The behaviour of the ISG was also investigated by different other authors [1,2,5,6], but mainly focussing on its dissolution at near neutral pH, depending on the type of radioactive waste repository chosen by the different countries involved in the collaboration.…”

Development the Economical Chemical Treatment Plant for Chromium Recovery From Tannery Waste Water

“…Finishing chemicalsalso react with the proteins of collagen fiber of tanned leather and these chemicals are mixed in side of the leather skins. But due to limited absorbing of chemicals in leather, some quantity go to the waste and making waste water [6]. The present studies an attempt has been made to economically chromium recovery plant from tannery waste with Assessment of the present situation.…”