Continuous-Flow Leach Tests of Simulated High-Level Waste Glass in Synthesized Groundwater and Deionized Water

• Published in: Journal of nuclear science and technology Vol. 24; no. 4; pp. 308 - 314
• Main Authors: KAMIZONO, Hiroshi, SHIMIZU, Isamu, BANBA, Tsunetaka
• Format: Journal Article
• Language: English
• Published: Tokyo Taylor & Francis Group 01.04.1987; Atomic Energy Society of Japan; Taylor & Francis Ltd
• Subjects: Applied sciences; borosilicate glass; deionized water; Exact sciences and technology; flow rate; geologic disposal; high-level radioactive wastes; leach test; leaching; Pollution; radioactive waste disposal; Radioactive wastes; simulations; synthesized ground-water; Wastes; Borosilicates; Radioactive waste; Simulation; Underground storage; Pollution prevention; Vitrification; Check; Leaching; Contamination; Ground water; Environmental protection
• ISSN: 0022-3131; 1881-1248
• DOI: 10.1080/18811248.1987.9735807

Simulated high-level waste glass was leached at 70°C for 28 d in one type of synthesized groundwater in Japan and in deionized water. The MCC-4 low-flow-rate leach test method was used for producing continuous-flow leach conditions with flow rates of 0.1, 0.01 and 0.001 ml/min. The MCC-1 static leach tests were also carried out for a comparison. First, the increase of the normalized elemental mass losses (NL) for Si and B was observed for all flow rates studied using synthesized groundwater and for flow rates of more than 0.01 ml/min in deionized water. This was in line with the results of several other previous studies. Second, in the deionized water, the values of NL by the MCC-1 method were larger than those obtained by the MCC-4 method with flow rates of 0.001 and 0.01 ml/min. Since the deionized water does not have buffer capacity, the pH-value in the MCC-1 leach tests was higher than those in the MCC-4 leach tests with flow rates of 0.001 and 0.01 ml/min, thereby helping the glass to dissolve progressively in the MCC-1 static conditions.