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Emerging Technologies for the Treatment of Organic and Aqueous Waste Streams:
International and U.S. Department of Energy Case
Studies
Dennis Kelley, Pacific Nuclear Solutions
Objectives of Presentation
• Examine several case studies that describe polymer solidification technology for use on complex liquid waste streams:– STMI-Areva, France– British Nuclear Group, Sellafield, U.K.– Cernavoda, Romania; Krsko, Slovenia & OPG
Canada– Khlopin Radium Institute, St. Petersburg, Russia– China Institute of Atomic Energy, Beijing, China– U.S. DOE Rocky Flats, Colorado– U.S. DOE Mound, Ohio
Nochar Polymer Technology
• ABsorbent, mechanical process; not an ADsorbent material (surface collector)
• Not an encapsulation technology• Minimal volumetric increase: 5% or less• No leaching / no liquid release• Solidification time: 1 hour to 48 hours depending
on waste stream composition• Mechanical / chemical reaction; no heat build-
up, no heat release• Polymers reduce the risk of fire; suppress vapor
Polymer Technology
• Stability of Solidification: Cobalt 60 gamma– 270 million rad on organic / acid waste– 90 million rad on organic waste – TBP– 75 million rad on aqueous waste – 14.2 pH
• Helps to immobilizes heavy metals• Safe / simple process: mixing or no mixing,
depends on composition of waste stream• Final product for short, intermediate or final
storage / burial• Incineration: less than .02% ash• Combined with grout / cement for monolithic
matrix possible
Polymers• N910: styrene block co-polymer– styrene-ethylene/butylenes-styrene
• N960: 100% cross linked, co-polymer of acrylamide
France
• Partner: STMI (Areva Group)• 2003, analyzed 20 year old tank waste• 4 phase complex organic / aqueous waste
stream, with alcohol and solid material• Good characterization made testing easy• Polymer formulas created according to each
phase• 2 : 1 bonding ratio for each phase• Encapsulation of polymer waste in cement
France
• Cementation tests – passed ANDRA requirement, but not cost effective
• ANDRA does not accept sorbent (organic) materials
• Incineration at Centraco• 2007 project at AREVA – Marcoule
– Complex aqueous waste stream with low pH• 2010 project at AREVA SICN Veurey
– DU, oils & solvents + low amount of water, classified as “liquid muds”
U.K. Contacts
• Sellafield• NNL, Workington• AWE, Aldermaston• UKAEA, Harwell• LLWR / NDA• Magnox stations, Berkeley• British Energy• AMEC• NSG Environmental
United Kingdom - Sellafield
• Oil immobilization program initiated by British Nuclear Group: 2006
• Waste oil, non-standard waste stream, treatment and disposal issues on site
• Waste Characterization & Clearance group and PNS conducted 3 experimental campaigns
• Small scale test program: 90+ oil types
Experimental Methodology
• Polymers: N910, N935, N960
• 1.5 : 1 ratio (liquid to polymer by weight)
• Light mixing applied if “pooling” occurred on surface, due to quick solidification
• Curing period: 24 – 48 hours
• Polymers blended, depending on waste composition
• Compositions unknown
I024-A Sample at 24 Hours
I048-A Sample at 24 Hours
Oil Solidification at Different Ratios
Results of Experiments:British Nuclear Group Analysis
• Polymer systems proved effective in immobilization of waste oil into a solid product
• No leaching of liquid on compression• Need to test for compatibility of polymers
to waste and assess ratios on case by case basis
• 2 : 1 ratio is optimum for economic and security reasons
Cementation Test Program
• UK Conditions for Acceptance for LLW disposal call for compressive strength minimum
• Consider cement encapsulation of polymer solidification to be suitable for final disposal
• Tests demonstrated oil solidification + grout can form a safe, non-compactable matrix suitable for final disposal
U.S. Department of Energy’s Initiatives for Proliferation Prevention in Russia:
Results of Radioactive Liquid Waste Treatment Project, Year 1
Y. Pokhitonov, V. KamachevV.G. Khlopin Radium Institute, Russia
D. KelleyPacific Nuclear Solutions, USA
Russia since 2002
• Partner: Khlopin Radium Institute, St. Petersburg
• Over 60 tests conducted on complex liquid waste streams: Gatchyna and RADON – Sosnvoy Bor NPP
• Sludge types from decontaminating solutions• Several forms of TBP from extraction facility for
spent fuel reprocessing• Spent extractant solutions with heavy metal
content
Oil SludgeNitric Acid
with Plutonium
Purpose of Project
• Program sponsored by DOE to engage Russian weapons scientists in peaceful use of existing and newly developed technologies
• DOE’s IPP program is a mechanism for U.S. private sector companies to enter Russian market: radwaste treatment
• Introduce USA environmental technology to weapons sector and seek joint technologies
• Investigate solutions for Russia & USA liquid radwaste problems resulting from Cold War
• DOE compensates scientists to participate in program• Long-term, commercialize project, employ scientists
Project Participants
• Russia– Russian State Atomic Energy Corporation (ROSATOM)– VG Khlopin Radium Institute (project manager)– Seversk (SCC ), Zheleznogorsk (MCC), Ozersk (MAYAK),
Gatchyna– 90+ participants, 68 weapons scientists
• USA– Department of Energy (GIPP)– Argonne National Lab– Pacific Nuclear Solutions (project manager)
• International Science & Technology Center (ISTC)– Project administrator, Moscow
Experiments
• Stability (Differential Thermal Analysis)• Irradiation• Gas generation• * Polymer solidification /capacity /
evaporation• * Leaching / water contact• * Encapsulation in cement
* Represents test data / results published in paper
Differential Thermal AnalysisPolymers: N910, N930, N960
Solidified samples with nitric acid and sodium nitrate possess high thermal stability
-8
-6
-4
-2
0
2
fact
um
wei
gh
t ch
ang
e (%
/°C
)
-100
-80
-60
-40
-20
0
20
wei
gh
t ch
ang
e (%
)
0 50 100 150 200 250 300 350 400 Temperature (°C)
910.002 ––––––– 930.001 – – – – 960.001 ––––– ·
Universal V4.4A TA Instruments
Irradiation Tests / Results
• Extensive irradiation testing conducted, required for ROSATOM certification
• All high dose rates• Cobalt 60 gamma irradiator• One example: nitric / organic solution
30 rad per second30 days = 77 M Rad+ 73 days = 270 M Rad
• Brittle, size reduction, no degradation / leaching• Conducted for gas generation tests
Stability and IrradiationCobalt 60, gamma installation, dose rate 3.9·10⁶ grayN960 polymer, HNO₃, 1M, after irradiationN910 polymer, oil + TBP, after irradiation
Irradiation Tests
Gas Generation Tests
• Preliminary tests, more testing and analysis is required
• Tests required to determine fire and explosion safety conditions
• Tests carried out under static conditions in sealed glass ampoules
• N960 polymer + nitric solution: no changes in the solidification and no gas release
• N910 polymer + TBP / oil: variable results • Preliminary judgment: polymers are not gas
generators
Rate of gas release during irradiation of sample: N910 polymer + 50%-TBP / 50%-oil
-0,02
0,00
0,02
0,04
0,06
0,08
0,10
0,12
0,14
0,16
0,18
0,20
0 100 200 300 400 500 600 700 800 900 1000
Dose, Grx103
W, m
l/h
Characteristic (composition)
of wastesConditions of solidification
Results
Volume of waste used, ml
Amount of # 960 used, g
Amount of # 910 used, g
4232Sludge residue from the bottom of the apparatus (aqueous phase). U-80g., NaNO₃~200g, HNO₃-0,8 M/I
6 8 0,5Successfully
solidified
4231
Sludge residue from the top of the apparatus (occurrence of organic
phase is probable). U-80g., NaNO₃~200g, HNO₃-0,8 M/I. Very thick black
liquid.
6 8 0,5Successfully
solidified
4237
LL decontaminationg solution with low amounts of organic substances, U-153 g/l, NaNO₃~100-150g, HNO₃
2,5 M/I
12 8 0,5Successfully
solidified
4238
LL decontaminating solution with low amounts of organic substances. U-153 g/l, NaNO₃~100-150g, HNO₃
2,5 M/I
20 4 2Successfully
solidified
4125U-20 g, NaNO₃40g, HNO₃1,2 M/I.
There was a precipitate in the solution.
15 16 0,5Successfully
solidified
4283Uranium re-extracts. U-70g, HNO₃
0,07M/I. 20 4 1Successfully
solidified
Solidified sample after addition of waterSolution: HNO₃ 1,0M
No volumetric increase
Polymer Solidification/ Capacity / Evaporation: Conclusions
• Polymer technology is irreversible, liquid permanently immobilized in polymer matrix
• Advantage: direct application of polymer to waste without conditioning / additives
• Little or no volumetric increase in the process• Appreciable volume reduction through evaporation;
no measurement of water vapor• Polymers slow evaporation process• Polymers are versatile, solidify aqueous / organic
waste of varying acidities, specific activities, suspensions and sludge types & salts
Chemical Stability – Leach Test
• Various leach tests conducted– samples with cesium and water contact– samples mixed with cement
• Aqueous polymer has capacity limits, water contact will cause leaching
• Cementation may be required by regulators• Cementation tests not conducted properly; precise
bonding ratios are necessary• Results:
– Immediate contact with water after solidification caused leaching
– Better results when sample had aged 1 month
Encapsulation of Polymer Solidification
• Cementation tests at AREVA & Sellafield successfully completed, with 90% organic / 10% aqueous streams
• When aqueous is above 10%, new technique for encapsulation is required
• Encapsulation research underway:– additives to solidification– additives to cement– tests with inorganic materials encouraging
Applications
• Waste in above ground & underground tanks
• Small containers / drums / self-contained generator (Yttrium -90)
• Direct application to closed vessels to prevent leakage
• Emergency spills at NPPs
• Decommissioning sites, legacy waste
Markets
• Weapons production sites• Nuclear power plants• Submarine decommissioning• Toxic chemical industrial complexes• Research institutes• Uranium mining• Medical waste• Land & water remediation projects
Year 2: Work Plan
• Polymer certification– Required to import & sell polymer in Russia– Licenses required for health / safety, fire /
explosion, irradiation / stability– Final certification issued by ROSATOM
• Commence sub-site test work– Active solutions– Problematic waste streams
• Continuation of experiments
Cernavoda, Romania
• Cernavoda NPP approval – 2005• CNCAN approval – early, 2007• Waste streams to be solidified:
– mineral oil with tritium / cesium, 200+ drums completed
– machine oil with tritium– scintillation fluid
• Interim storage on-site (20+ years), plan to incinerate at Studsvik, Sweden
Krsko, Slovenia
• First Nochar user in Europe, 2002
• Oil with tritium / solvents
• Waste transported to Studsvik Nuclear, Sweden for incineration
• Incineration with excellent results
• Safety booms in power plant for emergency spills
Ontario Power Generation - Canada
• 2010 test program– FRF, Fire Resistant fluid for turbine governing
system– Paint, latex (used N930)– Glycol (used N935)– Kodak developer (used N960)– Solvents, machine oil
China
• China Institute of Atomic Energy, Beijing
• Test program 2004-2005
• Formal paper published
• Waste treatment regulations to be changed
• Repository conditions, similar as WIPP-DOE, desert conditions
• 1st large scale project underway
Waste Streams
• Six simulant waste streams tested:– Tri-butyl phosphate: 30% TBP / 70%
kerosene– Acidic (nitric) solution: less than 0 pH– Alkaline solution: more than 14 pH– Ion exchange resin: anion to cation – 2:1
• Sodium type-beads, chlorine type-beads & 50% water
– Vacuum pump oil– Scintillation fluid
Solidification of TBP/OK
Test number
Liquid waste
(g)
Polymer (g)
Remarks Stir After 6 weeks
1-1 8g 8g
N910
Waste added to the polymer. Rapid reaction,
about 20 secondsPolymer Not fully consumed
noNo significant
variance
1-2 24g 8g
N910
Waste added to the polymer. Rapid reaction. Not
fully consumed - small amount of dry polymer at
bottom of beaker
no
Become translucent like glass; elasticity
increase
1-3 24g 8g
N910 + N960
Waste + water added to the polymer. Rapid reaction
Polymer not fully consumed yes
Become translucent like glass; elasticity
increase
1:1 Ratio after 6 weeks 3:1 Ratio after 6 weeks
Sodium Cation Exchange Resin Solidification
Test number
Liquid Waste (g)
Polymer (g) Remarks StirAfter 6 weeks
5-1
100g(about 50%
water)
20g N960
Resin particles are embedded in the
polymer massyes
No significant variance
Irradiation Tests
• Objectives of irradiation tests of solidified waste streams:– Evaluate degradation of waste form and polymers– Leaching– Durability– Waste sealed in individual ampoules– Cobalt-60, gamma source irradiator – Dose rate: 28 rad per second / 70 million rad– All samples exposed to same dose rate – Loose polymers also irradiated at same dose rate
Irradiation of Vacuum Pump Oil70 Million Rad
IR Spectra-graph Tests/Results
• Objective: check for degradation of polymers resulting from irradiation
• 100,000 rad for 100 hours = 10,000,000 rad
• Conclusion: Little or no degradation of polymer
IR Spectra-graph of N910
Red represents after irradiationBlue represents before irradiation
IR Spectra-graph of N960
Red represents after irradiationBlue represents before irradiation
U.S. Department of Energy – Rocky Flats,Colorado
• One of DOE’s first major nuclear weapons sites declared a full closure site
• Objective: treat and remove all “orphan” waste streams• Polymers evaluated and approved for solidification of
transuranic (TRU) waste with leach tests (EPA # 1311), hydrogen gas tests
• Replaced cementation as treatment method• TRU oil with plutonium waste streams solidified:
- methanol with organic contaminants such as cyclohexane- mixed organic waste consisting of freon, carbon tetrachloride and trichloroethylene- contaminated used pump oil
• TRU acid (cerium nitrate) with plutonium
TRU Oil Solidification with N990
DOE – Rocky Flats
• Create layering process, 10 kgs per layer to avoid mixing
• Packaging: 55 gallon steel drums
• Final disposal at Waste Isolation Pilot Plant (WIPP), DOE’s ILW repository
• All waste moved and stored at WIPP
• Estimated DOE cost savings exceeded $10 million
U.S. Department of Energy – Mound, Ohio
• In 2000, full scale solidification of vacuum pump oil with tritium under EM-50 program
• 8,000 liters of oil• DOE required bonding ratio: 1 : 1
(liquid:polymer by weight)• N990 formula – to solidify oil and water, includes
catalyst for aged, low volatile oil• 50,000 curies of oil waste solidified over 3 year
period• 2,200 curie per liter solidified / shipped to NTS
DOE – Mound
• Extensive leach testing conducted • Extensive bench testing to determine
solidification production methodology• Final process - No mixing• Packaging: polyethylene liner / drum
overpack• DOE estimated cost savings: $ 1 million +• Final storage / burial at Nevada Test Site
(NTS) – DOE’s LLW site
Lawrence Livermore Project
• Depleted uranium tailings in oil
• 48 drums – completed
• N910 polymer (90%) + 922 metalbond (10%) formula
• 2 Step Process– Oil + polymer, cure then– Add cement to create a monolith
• Final storage at Nevada Test Site
Conclusions
• Accurate characterization of waste stream is critical to ensure good solidification
• Conduct bench test on each and every waste stream; eliminate surprises
• Packaging: must meet each country’s final disposal requirements; liners, drums, boxes, encapsulation in cement / other matrix, incineration
• Mixing: keep process simple / small batches