Dennis Kelley, Pacific Nuclear Solutions

• 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

• 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

• 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

– styrene-ethylene/butylenes-styrene
• N960: 100% cross linked, co-polymer of acrylamide

• 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

• 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”

• Sellafield
• NNL, Workington
• AWE, Aldermaston
• UKAEA, Harwell
• LLWR / NDA
• Magnox stations, Berkeley
• British Energy
• AMEC
• NSG Environmental

• 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

• 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

• 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

• 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. Kamachev
V.G. Khlopin Radium Institute, Russia
D. Kelley
Pacific Nuclear Solutions, USA

• 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

• 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

• 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

• Stability (Differential Thermal Analysis)
• Irradiation
• Gas generation
• * Polymer solidification /capacity / evaporation
• * Leaching / water contact
• * Encapsulation in cement
* Represents test data / results published in paper

20
0
910.002
930.001
960.001
2
0
-20
-40
-2
-4
-60
-80
-6
-100
0 50 100 150 200 250 300 350 400
-8
Temperature (°C) Universal V4.4A TA Instruments
Differential Thermal Analysis
Polymers: N910, N930, N960
Solidified samples with nitric acid and sodium nitrate possess high thermal stability

• Extensive irradiation testing conducted, required for ROSATOM certification
• All high dose rates
• Cobalt 60 gamma irradiator
• One example: nitric / organic solution
30 rad per second
30 days = 77 M Rad
+ 73 days = 270 M Rad
• Brittle, size reduction, no degradation / leaching
• Conducted for gas generation tests

Stability and Irradiation
Cobalt 60, gamma installation, dose rate 3.9·10⁶ gray
N960 polymer, HNO ₃ , 1M, after irradiation
N910 polymer, oil + TBP, after irradiation

• 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
0,20
0,18
0,16
0,14
0,12
0,10
0,08
0,06
0,04
0,02
0,00
-0,02
0 100 200 300 400 500
Dose, Grx10
3
600 700 800 900 1000

Characteristic (composition) of wastes
Conditions of solidification
Results
4232
4231
4237
4238
4125
4283
Sludge residue from the bottom of the apparatus (aqueous phase). U-
80g., NaNO ₃~ 200g, HNO ₃ -0,8 M/I
Sludge residue from the top of the apparatus (occurrence of organic phase is probable). U-80g., NaNO ₃~-
200g, HNO ₃ -0,8 M/I. Very thick black liquid.
LL decontaminationg solution with low amounts of organic substances,
U-153 g/l, NaNO ₃~ 100-150g, HNO ₃-
2,5 M/I
LL decontaminating solution with low amounts of organic substances.
U-153 g/l, NaNO ₃~ 100-150g, HNO ₃-
2,5 M/I
U-20 g, NaNO ₃ 40g, HNO ₃ 1,2 M/I.
There was a precipitate in the solution.
Uranium re-extracts. U-70g, HNO
₃-
0,07 M/I.
Volume of waste used, ml
Amount of # 960 used, g
Amount of # 910 used, g
6
6
12
20
15
20
8
8
8
4
16
4
0,5
0,5
0,5
2
0,5
1
Successfully solidified
Successfully solidified
Successfully solidified
Successfully solidified
Successfully solidified
Successfully solidified

Solidified sample after addition of water
Solution: HNO ₃ 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

• 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

• 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

• 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

• Weapons production sites
• Nuclear power plants
• Submarine decommissioning
• Toxic chemical industrial complexes
• Research institutes
• Uranium mining
• Medical waste
• Land & water remediation projects

• 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 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

• 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

• 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 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
• 1 st large scale project underway

• 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

Test number
Liquid waste (g)
Polymer
(g)
1-1
1-2
1-3
8g
24g
24g
Remarks Stir After 6 weeks
8g
N910
8g
N910
Waste added to the polymer.
Rapid reaction, about 20 seconds
Polymer Not fully consumed
Waste added to the polymer.
Rapid reaction. Not fully consumed - small amount of dry polymer at bottom of beaker no no
No significant variance
Become translucent like glass; elasticity increase
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

Test number
Liquid
Waste (g)
5-1
100g
(about
50% water)
Polymer (g)
20g
N960
Remarks
Resin particles are embedded in the polymer mass
Stir yes
After 6 weeks
No significant variance

• 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

• 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

Red represents after irradiation
Blue represents before irradiation

Red represents after irradiation
Blue represents before irradiation

• 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

• 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

• 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

• 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

• 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

• 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