emerging technologies for the treatment of organic and aqueous waste streams: international and u.s....

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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

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