Modelling the physico-chemical speciation of plutonium in the eastern Irish Sea: a further development

A numerical full three-dimensional model previously developed to simulate the physico-chemical speciation of plutonium in the eastern Irish Sea has been improved. The model solves simultaneously the hydrodynamic equations, the suspended matter equation and the equations that give the time evolution...

ver descrição completa

Detalhes bibliográficos
Autor: Periáñez Rodríguez, Raúl
Tipo de documento: artigo
Estado:Versión enviada para evaluación y publicación
Data de publicação:2002
País:España
Recursos:Universidad de Sevilla (US)
Repositório:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/132058
Acesso em linha:https://hdl.handle.net/11441/132058
https://doi.org/10.1016/S0265-931X(01)00168-0
Access Level:Acceso aberto
Palavra-chave:Plutonium
Irish Sea
Modelling
Sediments
Kinetic coefficients
Speciation
Descrição
Resumo:A numerical full three-dimensional model previously developed to simulate the physico-chemical speciation of plutonium in the eastern Irish Sea has been improved. The model solves simultaneously the hydrodynamic equations, the suspended matter equation and the equations that give the time evolution of Pu concentrations in water, suspended matter and bottom sediments. It is considered that Pu may exist in each phase in two different oxidation states. Redox reactions are also considered. In the earlier version of the model, a one-step kinetic model was used to describe the transfers of radionuclides between the dissolved and solid phases. Although with this kind of model the contamination of the sediments can be properly simulated, it is clearly not able to describe the re-dissolution of radionuclides from a contaminated sediment once the external source to the sea is reduced. Thus, the model has been improved by substituting the one-step model with a two-step kinetic model consisting of two consecutive reversible reactions. Now it is possible to simulate both the sediment contamination and the re-dissolution processes.