Application of a gamma RS index-based method and techno-economic analysis for in situ treatment of Cs-137-contaminated soils by cement-barite based stabilisation/solidification

作者：Falciglia Pietro P; Romano Stefano; Vagliasindi Federico G A

来源：Journal of Environmental Management, 2017, 197: 619-630.

DOI：10.1016/j.jenvman.2017.04.037

• (137)Caesium (Cs-137)
• gamma-radiation shielding (gamma RS) index
• Costs
• Effective dose
• Stabilisation/solidification (S/S)

This paper examines the application of cement (C)-barite (Ba) based-Stabilisation/Solidification (S/S) for the remediation of Cs-137-contaminated soils, investigating the influence of soil: grout and C: Ba ratios on the shielding performance of the S/S mix assessed as gamma radiation shielding (gamma RS) index variation. Results from experiments were used to perform a novel approach and an economic analysis in order to calculate the effective dose reduction achievable by S/S and to assess the optimum quantities and costs of selected mixes, respectively.
Gamma ray spectrometer measurements indicate that gamma RS index increases with increasing barite percentage up to a maximum level of 50%; however a further increase results in a worsening of the shielding performances. A maximum gamma RS variation of 46.5% was recorded with grout percentage increasing from 16.6 to 50%. At the photon energy of 662 keV (Cs-137), the maximum grout amount results in the possibility to shield up to 24.1% of gamma-rays emitted. The effective dose reduction achievable by the investigated S/S allows a maximum Cs-137-soil contamination in the range 2.94-14.55 kBq kg(-1) successfully treatable employing a soil: grout ratio of 1: 1 (C: Ba = 1:1). Technical data, jointly with economic analysis findings, make cement-barite based-S/S very competitive in cost-effectiveness and could provide a basis for decision-making of Cs-137-contaminated site remediation.

• 出版日期2017-7-15