E&P NORM Characteristics Gert Jonkers Engineering & Analytical - GSEA/4 “ Problem Solving ” - PowerPoint PPT Presentation

slide1 n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
E&P NORM Characteristics Gert Jonkers Engineering & Analytical - GSEA/4 “ Problem Solving ” PowerPoint Presentation
Download Presentation
E&P NORM Characteristics Gert Jonkers Engineering & Analytical - GSEA/4 “ Problem Solving ”

play fullscreen
1 / 15
E&P NORM Characteristics Gert Jonkers Engineering & Analytical - GSEA/4 “ Problem Solving ”
128 Views
Download Presentation
lavonn
Download Presentation

E&P NORM Characteristics Gert Jonkers Engineering & Analytical - GSEA/4 “ Problem Solving ”

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. E&P NORM Characteristics Gert Jonkers Engineering & Analytical - GSEA/4 “Problem Solving” (Shell E&P Ionising Radiation/NORM HSE Expert CHP) location Shell Research & Technology Centre, Amsterdam P.O. 38000 NL-1030 BN Amsterdam the Netherlands

  2. Naturally Occurring Radionuclides (NOR’s) vs. Anthropogenic Radioactivity • Cosmogenic NOR’s • induced by interaction between ‘particle radiation’ and elements in the outer atmosphere (“ionosphere”) thereby generating Naturally Occurring Radionuclides • 3H (T1/2 = 14 y), 7Be (53 d), 14C (5730 y), etc. • e.g.14N + 1n 1p + 14C; • Terrestrial NOR’s • radionuclides, which have been present ever since the planet Earth was formed some 4.5  109 years ago; • 40K (1.28  109 y), 87Rb (5  1011 y), 232Th (1.41  1010 y), • 235U (7.04  108 y), 238U (4.47  109 y) 7 0 1 6

  3. E&P RELEVANT TERRESTRIAL NOR’s 40K and 232Th-, 235U- & 238U- decay series RADIOACTIVITY Becquerel(1 nuclear disintegration/s) SI unit for total amount of radioactivity (Bq), or concentration of radioactivity (Bq/g or Bq/L) Half-Life time period, in which the total activity or activity concentration, is reduced to half its value PHYSICS/CHEMISTRY activity-mass conversion factors 00031.2 Bq[40K]/g[K] 04060.0 Bq[232Th]/g[Th] 00572.0 Bq[235U]/g[U] 12600.0 Bq[238U]/g[U]  40K 1.3 109 y << Low abundance, << homeostatic take up 0.01% 232Th 1.4 1010 y 100%.00 235U 4.5 108 y 0.27% << Low abundance 238U4.5 109 y 99.72%

  4. K, Th and U Concentrations in Sedimentary Rocks

  5. TERRESTRIAL NOR’s: 232Th- & 238U- Decay Series 238U109 y Primordial NOR’s 232Th and 238U are special Heading a Series of Successive Nuclear Decays 99.7% 234Th 234mPa 234U 232Th1010 y 230Th • Relevant Gas/Oil Time Scales • Diagenesis > 106 years • Reservoir Accumulation > 105 years • Production ~ 50 years • (Gas) Transport Time ~ days 100% 228Ra6 y 226Ra1600 y 228Ac 222Rn4 d 228Th2 y 218Po 224Ra 4 d 214Pb 220Rn 214Bi 216Po 214Po 212Pb 210Pb22 y 212Bi 210Bi Half-lives < “1 week” too short to develop the chemistry of the element 212Po & 208Tl 210Po138 d 208Pbstable 206Pb stable

  6. Secular Equilibrium 238U • Secular equilibrium is ‘radioactive’ equilibrium, in which the parent activity does not decrease significantly during many daughter half lives. A steady state is established in which the rate of formation of the daughter nuclides is just equal to their rate of decay. • The rate of decay, i.e. de number of disintegrations per second or Bq, of all radionuclides in a series in secular equilibrium will be the same as that of the parent. • The shorter-lived daughters then appear to decay with the half-life of the long-lived parent. • If undisturbed the daughters of the 238U-decay series all appear to decay with the half-life of uranium being 4.5 × 109 years. 234Th 234mPa 234U 230Th 226Ra 222Rn 218Po 214Pb 214Bi 214Po 210Pb 210Bi 210Po 206Pb

  7. Disturbed Secular Equilibrium 238U • If a “system” is not closed to radionuclide migration the secular equilibrium will become disturbed. The migrated daughter nuclide will start a decay series for its own, so-called sub-series will be formed. 234Th 234mPa 234U 230Th • For example: a “system” consists of a formation with entrapped pore water. As waters start to move, dissolved radium-ions may be transported to somewhere far from the originating formation, i.e. far from its parent 238U. Consequently, no ingrowth of 226Ra anymore by nuclear decay > unsupported. • 226Ra will form a new secular equilibrium with its short-lived daughters > 226Ra or 226Raeq sub-series. 226Ra 226Ra 222Rn 222Rn 218Po 218Po 214Pb 214Pb 214Bi 214Bi 214Po 214Po 210Pb 210Pb 210Bi 210Bi 210Po 210Po 206Pb 206Pb

  8. 232Th- & 238U- Decay Series Member Transport

  9. E&P NORM CHARACTERISTICS - 238U decay series 238U109 y 234Th NOR transport with reservoir material only 234mPa 234U105 y 230Th 105 y Leaching transport via water 226Ra1600 y 226Ra Emanation / Dissolution transport with gas / (oil/water) c) 222Rn 222Rn4 d 222Rn 218Po 218Po 218Po Leaching (Pb carrier) transport via water electrochemical deposition 214Pb 214Pb 214Pb 214Bi 214Bi 214Bi e) 214Po 214Po mechanism?transport via NGL/condensate 214Po 210Pb 210Pb 210Pb 210Pb22 y 210Bi 210Bi 210Bi 210Bi 210Po 210Po 210Po 210Po 210Po138 d 206Pb 206Pb 206Pb 206Pb 206Pb stable

  10. E&P NORM CHARACTERISTICS - 232Th decay series a) NOR transport with reservoir material only 232Th1010 y b) Leaching transport with water 228Ra6 y 228Ra 228Ac 228Ac 228Th2 y 228Th c) Leaching transport with water 224Ra 224Ra 4 d 224Ra Emanation / Dissolution transport with gas / (oil/water) 220Rn 220Rn1 min 220Rn 216Po 216Po 216Po 212Pb 212Pb 212Pb 212Bi 212Bi 212Bi 212Po&208Tl 212Po & 208Tl 212Po&208Tl 208Pb 208Pb stable 208Pb

  11. Activity Concentration Range: E&PProductStreams

  12. Activity Concentration Range: E&P Waste Streams

  13. External Dose Rate Range: E&P Facilities

  14. E&P NORM: What to Monitor?

  15. Knowing All This Impacts • Regulatory Requirements (Unwillingly & Surprisingly Encounter of E&P NORM, Low Specific Activity [IAEA transport regulations], large volume of Low Level Waste [IAEA waste definition], E&P vs ‘other’NORM) • Company Management System (Leadership & Commitment / Policy & Strategic Objectives / Organisation, Responsibilities, Resources, Competence, Standards & Documents / Hazards and Effects Management Process / Planning / Implementation, Corrective Action & Performance Reporting / Audit / Management Review) • External Radiation Survey Proactive Counteract E&P NORM Surprise (Inventory, Sampling, Measurement & Analysis, HSE rules – Operations & Maintenance) • Sample Measurement & Analysis (Standardised E&P NORM Analysis Methods, Standardised Reporting, Quality Assurance & Quality Control) • E&P NORM Disposal Options (long term risk/dose based, cost-benefit)