1. Only 1 glass specification "B" Solution characteristics Mg + Ga + Al + Cd + Ca + F+ Cl "A" Solution characteristics Na + Cd + Al + Fe + S + Ca+ F Velocity profile Thermoconvection cells in the molten glass Molten glass pathlines (3D view) Velocity vectors in a plane of the molten glass 3D model Modelling Gambit® Conduction, Natural convection, Forced convection and Radiation Thermal and Hydraulic Fluent® MeshingMelting pot and heating elements Temperature Air entrance at the bottom of the furnace Cooling study Pathlines around the melting pot Glass temperature Wall melting pot temperatures during the cooling Molten glass temperature Thermohydraulic modelling of the furnace from outer walls to the molten glass Temperature deviation between simulation and experiments very low in the molten glass Melting pot temperature cartography (sectional view) T. Brisbarre, P. Gruber, S. Lemonnier, J. Lacombe, Y. Papin, L. Pescayre, I. Hugon CEA Marcoule, DEN/DTCD/SCDV BP 17171, 30207 Bagnols-sur-cèze cedex, France Corresponding author : thomas.brisbarre@cea.fr Qualification of Liquid Fed In-Can Melting Process Applied to Vitrification of Nuclear Wastes : Description of Process and Equipment, Methodology and 3D Thermohydraulic Modelling High Activity Waste Solutions Characteristics Alpha bearing liquid waste 2 types of liquid waste 5 m 3 per year Operability Constraint Implementation in gloves boxes Feeding during the day Stand-by during the night Shut-down during week-end One batch a week Vitrification process 2 types of waste but only one glass specification Nominal Weekly Operating Schedule (ex: solution “B”) Context and constraints of the process In Can Liquid Fed Vitrification Process Expendable Canister in a furnace (no pouring) Liquid feeding of the melting pot (no calciner) Thermal homogenization obtained with thermoconvection only (no stirrer) Walls melting pot temperature = process setpoint temperature Process maintained under depression Resistance heating A strong and simple process Melting pot Cylindrical structure Molten glass Waste and glass frit feeding Heating elements Level 2 Glass Frit Feeding Selected Process Important facts: Nominal setpoint temperature: 1100°C Feeding rate: 5L/h Maximal glass production rate: 5kg/h Melting pot capacity: 108kg of glass Condenser Glass frit Recycling Feed tank Dust-Scrubber Additive Dust-scrubber draining At the end of the run Level 1 In-Can Furnace Level 0 Canister introduction Objectives Adjust the process Determine process parameter ranges Check glasses homogeneity Guaranty Glass packages will be in accordance with specifications Tests This program is based on five types of tests: Nominal tests (2 runs performed) Transient mode tests (2 runs performed) Degraded mode tests (4 runs and 1 performed) Sensitivity tests (2 runs for each type performed) - To the chemical of waste composition - To the operating conditions Test of suitability for actual process effluents Full-scale prototype Geometry Comparison with experimental results Only 1 glass specification Process qualification program T0 T0 + 1hT0 + 2h T0 + 3hT0 + 4h T0 + 5h Objectives Washing column Dust Scrubber Furnace with melting pot Extractor Diagram of full-scale pilot in direct vitrification configuration Optimize the choice of operating parameters of experimental studies Optimize the internal design In-Can furnace Improve the understanding of glass elaboration with this process Furnace schema