 |
|
|
|
 |
 |
© Serco Assurance 2001. All rights reserved
Last updated: 06-Mar-2003
We perform experimental investigations of solubility and sorption behaviour
for a wide number of elements and sorbing materials.
T.G. Heath, D.J. Ilett and C.J. Tweed, Development of a Near-Field Sorption Model for a Cementitious Repository, AEA Technology Report, AEAT/R/ENV/0229, 2000.
T.G. Heath, D.J. Ilett, N.J. Pilkington, C.J. Tweed, R.M. Wiggin and S.J. Williams, Modelling the Effects of Complexants on Radioelement Solubility, AEA Technology Report, AEAT/R/ENV/0230, 2000.
G.M.N. Baston, J.A. Berry, M. Brownsword, D.J. Ilett, C.M. Linklater, C.J. Tweed and M. Yui, Effect of Carbonate Concentration on the sorption of Plutonium onto Geological Materials, Mat. Res. Soc. Symp. Proc., 608, 293, 2000.
B.F. Greenfield, D.J. Ilett, M. Ito, R. McCrohon, T.G. Heath, C.J. Tweed, S.J. Williams and M. Yui, The Effects of Cement Additives on Radionuclide Solubilities, Radiochim. Acta 82, 27-32, 1998.
J. Bruno, L. Duro, J. de Pablo, I. Casas, C. Ayora, J. Delgado, M.J. Gimeno, J. Peña, C.M. Linklater, L. Perez de Villar and P. Gomez, Estimation of the concentrations of trace metals in natural systems. The application of codissolution and coprecipitation approaches to El Berrocal (Spain) and Poços de Caldas (Brazil), Chem. Geol., 151, 277-291, 1998.
G.M.N. Baston, J.A. Berry, M. Brownsword, T.G. Heath, D.J. Ilett, C.J. Tweed and M. Yui, The Effect of Temperature on the Sorption of Technetium, Uranium, Neptunium, and Curium on Bentonite, Tuff and Granodiorite, Mat. Res. Soc. Symp. Proc., 465, 805, 1997.
M.S.M Chan, R.J. Lynch and D.J. Ilett, Use of Cation Selective Membrance and acid addition for pH Control in 2-D Electrokinetic Remediation of Soil, Proceedings of EREM 2001, 3rd Symposium and Status Report on Electrokinetic Remediation, Karlsruhe, April 2001, Schriftenreihe Angew. Geol. Karlsruhe, 63 pp33-1 to 33-12.
Chemical modelling provides support to risk assessments from well-founded
chemical information and cost-effective solutions to disposal or waste-treatment
problems
HATCHES database is the source of thermodynamic data for HARPHRQ and CHEQMATE. It is quality-assured andPC-based and includes data on equlibrium reactions of 93 elements (including all major radionuclides and metals important in canister corrosion), 1500 aqueous species, range of organic and inorganic ligands and 900 solid phases. Close
GAMMON (GAs generation from Microbial degradation and Metal corrosiON) is a computer program developed on behalf of Nirex for modelling this gas generation. GAMMON models generation of gases from the coupled processes of anaerobic corrosion of metals (generating H2) microbial degradation of cellulosic wastes (generating CO2 and CH4). As well as the bulk gases, small quantities of radioactive gases may also be formed. In a repository for low- and intermediate-level waste, the principal radioactive gases formed are likely to be the 3H- and 14C-substituted isomers of the major bulk gases. For these radioactive gases, GAMMON can calculate generation rates as a function of time from a variety of sources. Close
CAMLE (Corrosion And Migration in Localised Environments) was developed to predict the solution chemistry and electrochemistry (and hence metal penetration rates) within a corroding cavity. It has been used to predict the rate of pitting corrosion for carbon steel embedded in a cementitious backfill. In modelling pitting corrosion, CAMLE considers the complex solution chemistry within the cavity; the electrochemical reaction rates and their dependence on parameters such as the electrostatic potential and the solution pH; the migration of ions under concentration and potential gradients; the advection of ions in flowing electrolytes; the effect of the changing shape and dimensions of the pit as propagation proceeds; and the effect of the blocking of the cavity with solid corrosion product. Close
CHEQMATE (CHemical EQuilibrium with Migration and Transport Equations) is used to examine coupling of ionic migration and chemical reactions in chemical and geochemical systems and to model heterogeneous reactions which evolve in time and space. It includes: 1D transport of ions by diffusion, advection, dispersion and electromigration; HARPHRQ; corrosion of metal surfaces; modelling of kinetically-controlled reactions. Close
HARPHRQ is a geochemical speciation program, developed on behalf of Nirex, that can be used to calculate: pH; Eh; quantity of minerals transferred into/out of solution as a function of reaction progress; and composition of solution in equlibrium with multiple phases solution compositions at fixed pH and/or Eh and at different temperatures.
HARPHRQ includes the HARSORB sorption module. HARSORB offers several sorption models, including: Simple Mass Action; Diffuse sorption; and Triple-layer sorption. Close |
|
||||||||||||||
|
|
||||||||||||||
|
|||||||||||||||
|
|
Last updated: 06-Mar-2003 |
||||||||||||||