Presentation on theme: "The Naturally Occurring Radioactive Materials (NORM) in"— Presentation transcript:
1The Naturally Occurring Radioactive Materials (NORM) in The Petroleum Industry andTheir Effect on The Health and Environmentالمواد المشعة الطبيعية الناجمة عن عمليات استخراج النفطفي الصناعات النفطية وتأثيراتها على الصحة والبيئة.اعدادد.خالد عجمي الربيعي/ قسم تكنولوجيا النفط /الجامعة التكنولوجيةد.محسن هاشم رسن / دائرة البحث والتطوير/ وزارة التعليم العالي
2What is NORM?NORM, or naturally occurring radioactive material, is found almost everywhere. In the exploration and extraction processes of oil and gas, the natural radionuclides 238U, 235U and 232Th, as well as the radium-radionuclides (223Ra, 224Ra, 226Ra and 228Ra) and 210Pb,.etc., are brought to the slurry surfaces and may contain levels of radioactivity above the surface background.The radionuclides of interest include long-lived radionuclides such asuranium-238 (238U)uranium-235 (235U)thorium-232 (232Th)and their radioactive decay products such as isotopes ofradiumradonpoloniumbismuthleadand individual long-lived radionuclides such aspotassium-40 (40K)rubidium-87 (87Rb)indium-115 (115In)
3NORM in the Oil and Gas Industry Oil and gas NORM is created in the production process, when produced fluids from reservoirs carry sulfates up to the surface of the Earth's crust. Barium, Calcium and Strontium sulfates are larger compounds, and the smaller atoms, such as Radium 226 and Radium 228 can fit into the empty spaces of the compound and be carried through the produced fluids. As the fluids approach the surface, changes in the temperature and pressure cause the Barium, Calcium, Strontium and Radium sulfates to precipitate out of solution and form scale on the inside, or on occasion, the outside of the tubulars and/or casing.On the other hand, NORM accumulated with time as sluge in petroleum refinery units
4Two decay series found in NORM deposits – from U-238 and Th-232. Why is it a hazard.The naturally radioactive material is concentrated into these deposits.They become sufficiently active to require precautions to be taken when working with them. They emit alpha, beta and gamma radiation.They also require to be disposed of in a controlled manner under International regulations.Two decay series found in NORM deposits – from U-238 and Th-232.Uranium-238 emits alphas, betas and gammas decaying through protoactinium, thorium, radium, radon, polonium and bismuth to stable lead-206.Thorium-232 emits alphas, betas and gammas decaying through radium, actinium, radon, bismuth, polonium and thallium to stable lead-208.
6Why NORM OccursReservoir rock contains small amounts of natural uranium and thorium and their radioactive daughters. One daughter, radium, is water soluble - dissolves in the reservoir water.Radium can precipitate with the barium and calcium ions to make any scales slightly radioactive. (NORM)Clay and fine particles can absorb the radium from the formation water.
7NORM in Gas WellsNORM can also be found in Gas Wells where no liquids are present.Here it is due to radioactive lead-210 plating out on surfaces from the gas.The gas is radioactive because of the radioactive radon gas in the formation accumulating in it.This radon then decays to the lead-210This layer is thin and cannot always be seen
8NORM Management Stop inhalation or ingestion of scale particles- Stop dust being createdStop dust becoming airborneStop dust from entering the bodyContain scale in one area and minimise contactTo achieve this we -Adhere to Local RulesKeep scale wet to stop dust risingWear personal protective equipmentSet up NORM Supervised Area and restrict contactضرورة عدم إستنشاق أو بلع الجزيئات الدقيقة للقشور ـضرورة عدم التسبب بحدوث الغبارضرورة عدم ترك الغبار في مكانه حتى تحمله الرياحضرورة عدم السماح للغبار بدخول الجسمضرورة حصر القشور في منطقة واحدة للحد من لمسها إلى أدنى درجة ممكنة.لتحقيق ذلك علينا ـالإلتزام بالقواعد والأنظمة المحليةإبقاء القشور رطبة لمنع تصاعد الغبارإستخدام معدات الوقاية الشخصيةتحديد منطقة لمراقبة المواد المشعة طبيعية المنشأ ومنع لمسها.
9Shell standard NORM meter for oil systems- Mini 900 with 44B probe. 5 cps above background is the lowest statistically reliable reading with the meterWe identify contamination, we do not measure scale or deposits activity.Using the Mini 900 a reading of 5 cps above background is NORM.Science of protecting people and the environment from the harmful effects of ionizing radiation, which includes both particle radiation and high energy electromagnetic radiation
10NORM RegulationsUnited States: still quarrelling between EPA and state departments whosits in the driving seat to regulate NORM (“How far should a risk-based approach in view of the natural background radiation dose be pushed. Latest CRCPD draft part N – 1999.Malaysian 1996: skipped formerly issued ‘release concentrations for solids’. Especially for scale and sludge disposal a “Radiological Impact Assessment” demonstrating compliance with the ICRP public dose limit is required.Canada 2000: previous guidelines reviewed and reissued nation-wide. “Unconditional Release Limits” derived from enveloping total-dose assessment scenarios provided for environmental media (air, water, soil). NORM dose constraint set at 300 mSv/y. Allowance for Conditional Release Limits by having carried out dedicated total-dose assessment scenarios.European Union: 2000 implementation of EC Directive 96/29/Euratom and accompanying guidance documents did not (yet) achieve full harmonisation for member state E&P NORM regulations.Middle East: several gas/oil producing states (Egypt, Oman, Syria, UAE) start to issue national E&P NORM Regulations.