r. gellermann, nov. 2009 prognosis of radioactivity in tenorm rainer gellermann, fugro-hgn gmbh,...

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Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail: [email protected]

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R. Gellermann, Nov Industrial process Industrial process Industrial process NORM industries Scales and sludges of oil or gas production Water treatment Filter dust of the hot metal production Extraction of Rare Earth Minerals Bauxite processing Phosphate processing Cement production Waste incineration Examples Dilution by mixing Enrichment by separation “Case A” and / or “Case B” Background radioactivity Enhanced natural radioactivity Raw materials Products, Wastes Case A Case B Case C

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Page 1: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

Prognosis of radioactivity in

TENORM

Rainer Gellermann, FUGRO-HGN GmbH, BraunschweigMail: [email protected]

Page 2: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

Industries and materials

TENORM

Technologically enhanced NORM

Page 3: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

Industrial process

Industrial process

Industrial process

NORM industries

Scales and sludges of oil or gas productionWater treatmentFilter dust of the hot metal production

Extraction of Rare Earth Minerals Bauxite processingPhosphate processing

Cement productionWaste incineration

Examples

Dilution by mixing

Enrichment by separation

“Case A” and / or “Case B”

Backgroundradioactivity

Enhanced naturalradioactivity

Raw materials

Products, Wastes

Case A Case B Case C

Page 4: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

The questions from the undertakings

OK, we know we have to deal with radioactivity.But: • What happens, if our technology is changed?• How much NORM-wastes will arise in a

certain facility?• How can the exposure of the employees

from NORM-waste be influenced?

Page 5: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

The expected changes

NORM shall be considered as planned exposure situation

are we able to “plan” NORM amounts arising in a certain facility in advance?

How we can make prognosis on NORM wastes? (activity concentrations and masses!!)

Page 6: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

There is a lot of experience

We know waste masses and activities of TENORM in industries.We know, that radioactivity may be enriched by technical processes

0,1

1

10

100

1000

1 10 100 1000 10000 100000 1000000

Mass in t

Spec

ific

activ

ity in

Bq/

g

Scales

Sludges

Bauxite

Filter dust

Mineral sands

Phosphate

Page 7: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

But …

we tell us stories about radioactivity

We have examples and explanations on a qualitative level – no theory, no quantifying models, no established terms for characterising the processes of RN enrichment.

What we need is a helpful tool for analysing the processes which may result in TENORM + to communicate about these processes in an easy comparable way.

Page 8: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

The general approach

TENORM consists of two components:

• Several radionuclides • A non-radioactive carrier

The non-radioactive carrier is an inherent part of any TENORM!

Molten silicates + RN slag

BaSO4 + Ra scale

Sand/clay + RN red mud

….

Conclusion:We have to deal with both: radioactivity AND masses!

Page 9: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

The problem: complex systems

Real processes: pig-iron plant / steel mill

Page 10: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

Phenomenological model of TENORM formation

Raw Material (A)

Additive (Z)uschlagstoff Product / depleted fraction

Residue / enriched fraction

Process

Balance equations

Mass balance: MMAA + + MMZZ = = MMRR + + MMPP Activity balance: : AAAA + + AAZZ = = AARR + + AAPP

ZA

R

MMM

MTF

ZA

R

AAAATF

ZFiMTFiATF

iaia

iEFA

RRA

)()(

)()(

)(

)(/)(1)(/)(1iMiMiAiA

ZFAZ

AZ

Process parameters 1: Transfer factors Process parameter 2: Enrichment factor

Additive factor

For every RN

Page 11: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

Elementary processes

Processes Type of residue Parameters and processes affecting the radionuclide enrichment

Physical processes Thermal volatilisation Filter dust (from mineral

sintering, blast furnace smelting or other thermal processes)

Temperature (above 1000°C); total mass fraction of dust (!); content of other volatile components

Solubility of chemical elements in the molten metal

Slag Grade of ore; volatilisation (Pb-210, Po-210)

Sorption of dissolved radionuclides on oxide hydrate surfaces

Filter sands in water treatment Ra-concentration of raw water; chemical composition of raw water; duration of filter use

Chemical processes (Chemical reactions) Incineration; combustion of carbon

Ashes Carbon content of fuel

Precipitation of Ba-Sr-sulfates from water or brines

Scales, sludges (oil or gas production; geothermal plants, etc.)

Concentration of Ba-Sr-Ca in the water or brine

NaOH treatment of bauxite Red mud Grade of ore Sulphuric acid treatment of phosphate ore

Phosphogypsum Grade of ore

Page 12: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

Iron smelting

Page 13: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

0,01

0,10

1,00

10,00

100,00

1000,00

10000,00

100000,00

1E-05 1E-04 1E-03 1E-02 1E-01 1E+00

Massentrennfaktor MTF

Anr

eich

erun

gsfa

ktor

EF

Result: large enrichments occur only in processes with small MTF

ZFiMTFiATF

iaia

iEFA

RRA

)()(

)()(

)(

ATF = 1 (borderline)

ATF = MTF

A

R

Theory

Page 14: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

Conclusion

· The radioactivity of wastes is only partially determined from the radioactivity of raw materials. The transfer of radionuclides into waste may result in an increase of activity concentrations which cannot be disregarded from the radiation protection point of view.

· Because high radionuclide enrichments are attributed to (very) low mass transfer factors, wastes with high activity concentrations occur usually in mass streams of technological processes, which constitute a small fraction of the total mass streams.

· Processes with mass amounts of products and wastes in the same order of magnitude are less sensitive in regard to changes of activity concentrations in the waste. Here the EF are low and the activity of wastes can be well estimated from the activity concentration of raw materials. (e.g. aluminia production from bauxite).

· Activity concentrations in wastes arising from processes with high enrichment factors are very sensitive in regard to any changes of masses in the process. That’s why the activity concentrations of scales in oil and gas production vary in different facilities in a poorly predictable degree.

Page 15: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

Real processes

Pb-210

0,01

0,10

1,00

10,00

100,00

1000,00

10000,00

100000,00

1E-06 1E-05 1E-04 1E-03 1E-02 1E-01 1E+00

Massentrennfaktor MTF

Anr

eich

erun

gsfa

ktor

EF

Pb-2

10

Scales, ErdgasScales, ErdölScales, GeothermieSchlämme, SteinkohlenbergbauSchlämme, WasserwerkStäube, Schlämme GranitbearbeitungSchlämme, Kohleaufarbeit.PhosphogipsRotschlammAufschlussrückstand TitanerzP-SchlackeFe-SchlackeFilterstaub (Fe, P)Steinkohlen AbsetzbeckenschlammKraftwerk-FilterstaubKraftwerk-Filterpressen schlammREA-GipsHolzkraftwerk, FeuerraumascheHolzkraftwerk, FilterascheGrenzlinie

Ra-226

0,01

0,10

1,00

10,00

100,00

1000,00

10000,00

100000,00

1E-06 1E-05 1E-04 1E-03 1E-02 1E-01 1E+00

Massentrennfaktor MTF

Anr

eich

erun

gsfa

ktor

EF

Ra-

226

Scales, ErdgasScales, ErdölScales, GeothermieSchlämme, SteinkohlenbergbauSchlämme, WasserwerkStäube, Schlämme GranitbearbeitungSchlämme, Kohleaufarbeit.PhosphogipsRotschlammAufschlussrückstand TitanerzP-SchlackeFe-SchlackeFe-FilterstaubSteinkohlen AbsetzbeckenschlammKraftwerk-FilterstaubKraftwerk-Filterpressen schlammREA-GipsHolzkraftwerk, FeuerraumascheHolzkraftwerk, FilterascheGrenzlinie

Precipitation, sorption from water

High temperature processes (without combustion)

Metal smelting – Slag

Page 16: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

Model parameters

Physical or chemical elementary process

MTF Radioelements (-nuclides) r

ATF (r) ZF (r) EF (r)

Thermal volatilisation (blast furnace, pig iron production)

0.005 Pb-210 0.9 1.4 250

U, Ra, Th 1 3 – 10 Solubility of chemical elements in the molten metal

0.1-0.3 Pb-210 0.1(b)

0.3 - 1

Sorption of dissolved radionuclides on oxide hydrate surfaces

< 1E-5 Ra 0.8-0.99 1 >1E+5

Incineration; combustion of carbon

0.1 – 0.01 U, Ra, Th 1 1 10 - 100

Precipitation of Ba-Sr-sulfates from water or brines

1E-5 Ra 0.1 1 1E+4

NaOH treatment of bauxite 0.3 U, Th, Ra, Pb-210 1 0.8 2.7 Th, Ra, Pb-210 0,9 0.55 Sulphuric acid treatment of

phosphate ore 0.72

U 0.1(a) 0.44

0.06

Page 17: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

Application 1: Combustion of peat

U-238 Ra-226 Pb-210 Th-232 K-40Peat Bq/kg 8 4 26 1 7fly ash Bq/kg 102 26 414 12 71bottom ash Bq/kg 122 30 129 5 109

EF(Fly ash) EF 12,8 6,5 15,9 12,0 10,1EF(Bott. Ash) EF 15,3 7,5 5,0 5 15,6

Page 18: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

Application 2: Mass-activity balance of a sinter facility

Sample Mass

(t) Mass Pb

(t)Pb-210Bq/kg

Pb 210 MBq

Ra226 MBq

Ore-coal-mix 1 1.388 1,82 133 185 5,3Ore-coal-mix 2 847 0,02 14 12 24,6F-Mix 581 1,34 3.300 1.917 4,6F-Mix 184 0,58 175 32 2,6F-Mix 188 0,53 153 29 1,5F-Mix 183 0,99 400 73 1,6Coke 99 0,01 90 9 2,1Mix V 506 0,96 20 10 2,0Input W 1.095 0,02 11 12 0,0input C 521 0,01 19 10 6,8Input V 330 1,09 25 8 0,6Dust C 339 3,84 14.600 4.956 16,6Sum Input SF 6.260 11,20 7 0,07

Sinter A 6.937 4,37 110 763 90,2Sinter B 28 6,37 158.000 4.471 0,1Residue 68 0,24 3.200 216 0,4Sum Output SF 7.033 10,97 5.449.932 90.728

Page 19: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

The next step

• Calculate EF from chemical data!

Page 20: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

Final remark

This approach was published in

Journal “Kerntechnik” 2008

Page 21: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

Nuclide compositions: 6 basic types of NORM

ai,Normalized = ai/(aU-238,max + aTh-232,max)

NORM: decay series usually in equilibrium

TENORM: processes including /applying water

Products: radionuclides technically isolated

Type M2 (Precipitates from water or aqueous solutions)

0

0,2

0,4

0,6

0,8

1

Th-232 Ra-228 Th-228 U-238 Th-230 Ra-226 Pb-210 Pa-231* Ac-227*

Nor

mal

ised

act

ivity

M2-Ra,old M2-Ra, young M2-Pb

Typ M3 (Residues of chemical extractions)

0

0,2

0,4

0,6

0,8

1

Th-232 Ra-228 Th-228 U-238 Th-230 Ra-226 Pb-210 Pa-231* Ac-227*

Nor

mal

ised

act

ivity

Tailings (U-mill, carbonate leaching)Chemical processing residue (Th-230 dominated)

Type M5 (Thermo-dust)

00,20,40,60,8

1

Th-232 Ra-228 Th-228 U-238 Th-230 Ra-226 Pb-210 Pa-231* Ac-227*Nor

mal

ised

act

ivity

Filter dust from blast furnace Silicate dust from Zr-TemperingFly ash from TPP

Type M1 (Raw materials)

0

0,2

0,4

0,6

0,8

1

Th-232 Ra-228 Th-228 U-238 Th-230 Ra-226 Pb-210 Pa-231* Ac-227*

Norm

alis

ed a

ctiv

ity

M1-U (U-dominated) M1-Th (Th-dominated)

Type M6 (Product)

0

0,2

0,4

0,6

0,8

1

Th-232 Ra-228 Th-228 U-238 Th-230 Ra-226 Pb-210 Pa-231* Ac-227*

Nor

mal

ised

act

ivity

U-metal Th-alloy,old Th-alloy,young Ra-paint,old

Type M4 (Slag, ash)

0

0,2

0,4

0,6

0,8

1

Th-232 Ra-228 Th-228 U-238 Th-230 Ra-226 Pb-210 Pa-231* Ac-227*N

orm

alis

ed a

ctiv

ity

Iron Slag Slag, ash from TPP

TENORM: processes applying fire

Page 22: R. Gellermann, Nov. 2009 Prognosis of radioactivity in TENORM Rainer Gellermann, FUGRO-HGN GmbH, Braunschweig Mail:

R. Gellermann, Nov. 2009

Conclusions

• Processes of TENORM formation can be used as guidance for classification of industries regarding NORM identification of materials which have to be investigated as residue.

• Processes result in specific nuclide compositions knowledge of the processes allows conclusions regarding radiological properties optimisation of measurements.