UNDERSTANDING COLD CAP - GLASS MELT CONVERSION FOR WASTE - PowerPoint PPT Presentation

UNDERSTANDING COLD CAP - GLASS MELT CONVERSION FOR WASTE VITRIFICATION AT THE HANFORD SITE, USA Jessica C. Rigby 1 , Anthony M. T. Bell 1 and Paul A. Bingham 1 , Ashutosh Goel 2 , John S. McCloy 3 , John D. Vienna 4 , Kevin M. Fox 5 , David K. Peeler 5 , Donna P. Guillen 6 1 Materials and Engineering Research Institute, Sheffield Hallam University, Howard Street, S1 1WB, UK; 2 Rutgers University, USA; 3 Washington State University, USA; 4 Pacific Northwest National Laboratory, USA 5 Savanah River National Laboratory, USA; 6 Idaho National Laboratory, USA

The Hanford Site, WA In Introduction 65% of total US plutonium production The Solution: including the Manhattan Project and Cold War Vitrification at Hanford's Waste Treatment Plants (WTPs). Final glass wasteform to be stored in geological repositories. Th Theory Exp Experimental Me Methods 200,000m 3 of radioactive defence wastes HL HLW-A1 A19 stored in 177 steel tanks HL HLW-NG NG-Fe Fe2 Future Wor Fu ork 2

Forming the Cold Cap In Introduction Waste and glass forming • chemicals are fed into the top of the melter. Theory Th Electrodes heat the melt to • 1150 o C Experimental Exp Methods Me Forced bubbling homogenises • the melt HLW-A1 HL A19 Glass is discharged through • port to cooling canisters Inside the Joule-Heated Ceramic Melter(P. R. Hrma, HLW-NG HL NG-Fe Fe2 Chun, Pierce, & Pokorný, 2013) In Incoming feed creates a batch • bl blank nket; the he co cold ca cap. Fu Future Wor ork 3

Inside the Cold Cap In Introduction Evaporation of Water • Boiling slurry Bo Dehydration • 100 100 o C Decarbonation and denitration • Th Theory Low-viscosity melt forming • Formation of continuous glass • 400 o C 400 forming melt Op Open porosity reaction layer Primary foaming caused by • Experimental Exp Methods Me mostly CO 2 evolution Primary foam collapse • Melt viscosity increases • 700 o C 700 Secondary foaming Sec • HL HLW-A1 A19 Foam Layer Fo Dissolution of Quartz • 800 800 o C Re Redox reactions and evolution of • 900 o C 900 SO 2 1000 o C 1000 HLW-NG HL NG-Fe Fe2 1100 1100 o C Glass melt Gl To what extent does the redox 1150 o C 1150 state of the melt effect the Cold cap profile showing temperature regions. Adapted from (Xu foaming? et al., 2016) Future Wor Fu ork 4

media Sample Preparation In Introduction Stages of Melting Study How can we analyse the cold cap? 800 o C 900 o C 1000 o C 1100 o C 1150 o C In situ observation • Th Theory Mathematical modelling • Exp Experimental Representative samples • Me Methods Laboratory Scale Melter Feed Expansion Tests HLW-A1 HL A19 HL HLW-NG NG-Fe Fe2 Fu Future Wor ork 5

HL HLW- Feed Compositions Raw Material Ra al Ox Oxide wt wt% A19/100g A1 Al(OH) 3 Al 2 O 3 37.18 24.53 Introduction In • Generic, simplified waste compositions H 3 BO 3 B 2 O 3 34.16 19.41 CaCO 3 CaO 1.09 0.61 • Specific waste streams with extreme levels Fe(OH) 3 Fe 2 O 3 7.44 5.61 of waste oxides: Li 2 CO 3 Li 2 O 8.92 3.64 NaOH Na 2 O 1.99 1.55 HLW-A19 SiO 2 SiO 2 22.15 22.35 Th Theory Zr(OH) 4 .0.65H 2 O ZrO 2 0.55 0.40 Na 2 SO 4 Na 2 O 0.36 0.16 SO 3 0.20 Bi 2 O 3 Bi 2 O 3 1.17 1.18 Cr 2 O 3 .1.5H 2 O Cr 2 O 3 0.62 0.53 Exp Experimental Ni(OH) 2 NiO 0.50 0.41 Me Methods PbO PbO 0.42 0.42 Fe(H 2 PO 2 ) 3 Fe 2 O 3 1.25 0.40 P 2 O 5 1.07 NaF Na 2 O 1.50 0.41 F 0.34 HL HLW-A1 A19 Na 2 CO 3 Na 2 O 10.66 6.29 NaNO 2 Na 2 O 0.35 0.16 NaNO 3 Na 2 O 1.24 0.46 Na 2 C 2 O 4 Na 2 O 0.13 0.06 CaSiO 3 CaO 9.71 4.73 SiO 2 5.07 HL HLW-NG NG-Fe Fe2 Sum 141.366 100 FEED EXPANSION TEST PELLET PROFILE AREA AS A FUNCTION OF Future Wor Fu ork TEMPERATURE FOR 6 VARIATIONS OF THE HLW-A19 FEED (HARRIS ET AL., 2017) 6

NG NG- Feed Compositions Raw Material Ra al Oxide Ox wt wt% Fe Fe2/100g Al(OH)3 Al2O3 8.61 5.63 Introduction In • Generic, simplified waste compositions H3BO3 B2O3 0.56 0.32 Na2B4O7.10H2O B2O3 37.16 13.57 • Specific waste streams with extreme levels Na2O 6.04 of waste oxides: CaCO3 CaO 0.94 0.53 CeO2 CeO2 0.12 0.12 HLW-A19 Th Theory Cr2O3.1.5H2O Cr2O3 0.30 0.25 Fe Fe(OH)3 Fe Fe2O3 20.54 20. 54 15. 15.35 35 HLW-NG-Fe2 La(OH)3 La2O3 0.11 0.09 Li2CO3 Li2O 3.87 1.57 Mg(OH)2 MgO 0.24 0.17 Experimental Exp MnO2 MnO2 3.98 3.98 Me Methods NaOH Na2O 0.81 0.63 Na2CO3 Na2O 4.04 2.36 Ni(OH)2 NiO 0.59 0.48 FePO4.2H2O Fe2O3 1.71 0.88 HLW-NG-Fe2 (Fe 3+ ) P2O5 0.78 HL HLW-A1 A19 PbO PbO 0.63 0.63 NG NG- Ra Raw Material Ox Oxide wt% wt Na2SiO3 Na2O 8.03 4.08 Fe Fe2/100g SiO2 3.95 Fe Fe(OH) 3 Fe Fe 2 O 3 20.54 20. 54 15. 15.35 35 Na2SO4 Na2O 0.39 0.17 HLW-NG-Fe2 (Fe 2+ ) SO3 0.22 SiO2 SiO2 37.33 37.33 (Fe 2+ ) Raw Material Ra Oxide Ox NG-Fe NG Fe2 (II)/100g wt% wt HLW-NG HL NG-Fe Fe2 SrCO3 SrO 0.28 0.20 FeC 2 O 4 .2 Fe .2H 2 O Fe Fe 2 O 3 34. 34.58 58 15. 15.35 35 ZnO ZnO 0.03 0.03 Zr(OH)4.0.654H2O ZrO2 1.57 1.13 NaNO2 Na2O 0.01 0.00 NaNO3 Na2O 0.45 0.16 Future Wor Fu ork H2C2O4.2H2O - 0.06 - 132.36 100.64 7

HLW-A19 Simplified Stages of Melting Study In Introduction 800 o C 900 o C 1000 o C 1100 o C 1150 o C Th Theory Experimental Exp Me Methods Simplified HLW A-19 Composition EVOLVED GAS ANALYSIS OF A-19 FEED BETWEEN 150℃ AND 1150℃(HARRIS ET AL., 2017) Oxide Raw Material mol% Target wt% XRF wt% 100,05 8E-11 OH H2O CO2 Mass/% HL HLW-A1 A19 Al 2 O 3 Al(OH) 3 16.73 25.13 29.16 7E-11 100 99,95 6E-11 B 2 O 3 H 3 BO 3 19.39 19.89 19.89 99,9 5E-11 Ion Current CaO CaCO 3 6.63 5.48 3.20 Mass/% 99,85 4E-11 Fe 2 O 3 Fe 2 O 3 3.47 8.16 10.04 HL HLW-NG NG-Fe Fe2 3E-11 99,8 Li 2 O Li 2 CO3 8.47 3.73 3.73 2E-11 99,75 99,7 1E-11 Na 2 O Na 2 CO 3 10.42 9.52 7.26 99,65 0 SiO 2 SiO 2 31.73 28.09 26.71 150 300 450 600 750 900 1050 Future Wor Fu ork Temperature TG-MS OF SIMPLIFIED A-19 BATCH BETWEEN 150℃ AND 1150℃

HLW-A19 LSM Sample HLW-A19 Simplified Stages of Melting In Introduction 800 o C Th Theory Exp Experimental 900 o C Me Methods 2cm 2c HLW-A1 HL A19 1000 o C HLW-NG HL NG-Fe Fe2 1100 o C Future Wor Fu ork 9

HLW-A19 LSM Sample HLW-A19 Simplified Phase Identification In Introduction 800 o C 900 o C 1000 o C 1100 o C 1150 o C 1150 o C + 1 hour Quartz Th Theory Magnetite Hematite Experimental Exp Me Methods Nepheline HL HLW-A1 A19 Nepheline NaAl(SiO 4 ) 800 o C 900 o C Magnetite 1000 o C Hematite 1100 o C Quartz 1150 o C 1150 o C + 1hr HL HLW-NG NG-Fe Fe2 10 CRYSTAL FRACTIONS IN HLW-A19 STAGES OF MELTING 100℃ TO 1200℃ (XU ET AL., 2016) Future Wor Fu ork 10 10

HLW-A19 LSM Sample EDX In Introduction Backscattere Ba Si Si Al Al Na Na d Th Theory Exp Experimental Me Methods HL HLW-A1 A19 HL HLW-NG NG-Fe Fe2 Future Wor Fu ork

HLW-A19 LSM Sample EDX In Introduction Fe Fe Ni Ni Cr Cr Backscattere Ba d Th Theory Exp Experimental Methods Me HLW-A1 HL A19 HLW-NG HL NG-Fe Fe2 Future Wor Fu ork 12

HLW-A19 Discussion In Introduction How well did the simplified stages of melting samples represent the cold cap sample? Quartz dissolution • Iron phases • Th Theory Gas-evolving reactions • Phases with other species, e.g. Ni, S, Cr • Evolution of nitrates and sulphates • Exp Experimental Which reactions have been explored in both the simplified and complex feeds? Methods Me Evaporation of Water • Dehydration • Decarbonation and denitration • Low-viscosity melt forming • HL HLW-A1 A19 Formation of continuous glass forming melt • Primary foaming caused by mostly CO 2 evolution • Primary foam collapse • Melt viscosity increases • HLW-NG HL NG-Fe Fe2 Secondary foaming Se • Dissolution of Quartz • Redox reactions and evolution of f SO SO 2 • Fu Future Wor ork 13

HLW-NG-Fe2 Fast Dried Slurry Solids In Introduction NG-Fe2 Fe 3+ Th Theory Experimental Exp Methods Me NG-Fe2 Fe 2+ HL HLW-A1 A19 HL HLW-NG NG-Fe Fe2 Future Wor Fu ork 14

Stages of Melting Samples Introduction In Fe3+1500 Fe2+ 1150 Theory Th NG-Fe2 Fe 3+ NG-Fe2 Fe 2+ Fe3+ 1100 Intensity (a.u.) Fe2+ 1100 Experimental Exp Me Methods Fe3+ 1000 1mm 1mm Fe2+ 1000 HLW-A1 HL A19 Quartz Unidentified Phase Fe3+ 900 Fe3+1500 Intensity (a.u.) Fe2+ 1150 Fe2+ 900 HLW-NG HL NG-Fe Fe2 Fe3+ 800 Fe2+ 800 15 25 35 45 55 65 75 Fu Future Wor ork Angle (2θ) 15 35 55 75 Angle (2 θ ) 15

video video Feed Expansion Tests Introduction In 10 9,43 9 Fe 2+ 8 Normalised Volume Fe 3+ 7 NG-Fe2 Fe 3+ Theory Th 6 5 4,73 4 3 2 Exp Experimental Me Methods 1 0 50 150 250 350 450 550 650 750 850 950 1050 1150 Temperature ( o C) 0 NG-Fe2 Fe 2+ -5 HLW-A1 HL A19 -10 Temperature Difference (μV) -15 -20 -25 HL HLW-NG NG-Fe Fe2 -30 -35 -40 -45 Fu Future Wor ork -50 16

Laboratory Scale Melter Introduction In Feed slurry: NG-Fe2 Fe 2+ (Iron Oxalate) Feed time: 40 mins Feed rate: 9rpm Theory Th Experimental Exp Methods Me Quenching Glass Melting Feeding HLW-A1 HL A19 1200 Plenum Temperature ( o C) 1000 Glass Melt 800 HLW-NG HL NG-Fe Fe2 1150 o C 600 400 200 0 Fu Future Wor ork 00:00:00 00:10:00 00:20:00 00:30:00 00:40:00 00:50:00 01:00:00 01:10:00 01:20:00 01:30:00 01:40:00 01:50:00 02:00:00 17 Run Time