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Sample records for high decontamination factors

  1. High pressure freon decontamination of remote equipment

    International Nuclear Information System (INIS)

    Wilson, C.E.

    1987-01-01

    A series of decontamination tests using high pressure FREON 113 was conducted in the 200 Area of the Hanford site. The intent of these tests was to evaluate the effectiveness of FREON 113 in decontamination of manipulator components, tools, and equipment items contaminated with mixed fission products. The test results indicated that high pressure FREON 113 is very effective in removing fissile material from a variety of objects and can reduce both the quantity and the volume of the radioactive waste material presently being buried

  2. Decontamination

    International Nuclear Information System (INIS)

    Montford, B.

    1975-01-01

    Development of special techniques has permitted the use of mild decontamination processes for the CANDU type reactor primary coolant circuit, overcoming many of the problems associated with conventional decontamination processes, which use strong, acidic reagents. (Author)

  3. Decontamination of high-level waste canisters

    International Nuclear Information System (INIS)

    Nesbitt, J.F.; Slate, S.C.; Fetrow, L.K.

    1980-12-01

    This report presents evaluations of several methods for the in-process decontamination of metallic canisters containing any one of a number of solidified high-level waste (HLW) forms. The use of steam-water, steam, abrasive blasting, electropolishing, liquid honing, vibratory finishing and soaking have been tested or evaluated as potential techniques to decontaminate the outer surfaces of HLW canisters. Either these techniques have been tested or available literature has been examined to assess their applicability to the decontamination of HLW canisters. Electropolishing has been found to be the most thorough method to remove radionuclides and other foreign material that may be deposited on or in the outer surface of a canister during any of the HLW processes. Steam or steam-water spraying techniques may be adequate for some applications but fail to remove all contaminated forms that could be present in some of the HLW processes. Liquid honing and abrasive blasting remove contamination and foreign material very quickly and effectively from small areas and components although these blasting techniques tend to disperse the material removed from the cleaned surfaces. Vibratory finishing is very capable of removing the bulk of contamination and foreign matter from a variety of materials. However, special vibratory finishing equipment would have to be designed and adapted for a remote process. Soaking techniques take long periods of time and may not remove all of the smearable contamination. If soaking involves pickling baths that use corrosive agents, these agents may cause erosion of grain boundaries that results in rough surfaces

  4. Decontamination using the high-pressure wet jet system

    International Nuclear Information System (INIS)

    Brandt, D.

    1985-01-01

    For decontaminating machine components, tools, instruments and scrap in nuclear plants the most varying decontamination procedures are used. At the nuclear power plant Wuergassen a mobile high-pressure wet jet unit, developed by Ernst Schmutz GmbH, was successfully used for the first time in extensive decontamination work. The recycling system integrated in the decontamination unit substantially reduces secondary waste, which is usually produced in large quantities by the dry jet method, and continually extracts the contaminated dirt thus guaranteeing full utilisation of the jet agent while preventing secondary contamination of the components to be treated. (orig.) [de

  5. Decontamination factors of ceramic filter in radioactive waste incineration system

    International Nuclear Information System (INIS)

    Kanbe, Hiromi; Mayuzumi, Masami; Ono, Tetsuo; Yoshiki, Shinya; Kouyama, Hiroaki; Nagae, Madoka; Sekiguchi, Ryosaku; Takaoku, Yoshinobu; Hozumi, Masahiro.

    1987-01-01

    A suspension-firing type radioactive waste incineration system is developed and cold demonstration testing of ceramic filters for the system are carried out. The incineration system, which is useful for a wide variety of waste materials, can serve to simplify the facilities and to reduce the costs for waste disposal. The incineration system can be used for drying-processing of concentrated waste liquids and disposal of flame resistant materials including ion exchange resins and rubber, as well as for ordinary combustible solid materials. An on-line backwash system is adopted to allow the ceramic filters to operate stably for a long period of time. For one-step filtering using the ceramic filter, the decontamination factor is greater than 10 5 for the processing of various wastes. In a practical situation, there exist vapor produced by the spray drier and the cladding in used ion exchange resin, which act to increase the decontamination performance of the ceramic filters to ensure safe operation. For the waste incineration system equipped with a waste gas processing apparatus consisting of a ceramic filter and HEPA filter, the overall decontamination factor is expected to be greater than 10 6 at portions down to the outlet of the ceramic filter and greater than 10 8 at portions down to the outlet of the HEPA filter. (Nogami, K.)

  6. Development of high-level radioactive waste treatment and conversion technologies 'Dry decontamination technology development for highly radioactive contaminants'

    International Nuclear Information System (INIS)

    Oh, Won Zin; Lee, K. W.; Won, H. J.; Jung, C. J.; Choi, W. K.; Kim, G. N.; Moon, J. K.

    2001-04-01

    The followings were studied through the project entitled 'Dry Decontamination Technology Development for Highly Radioactive Contaminants'. 1.Contaminant Characteristics Analysis of Domestic Nuclear Fuel Cycle Projects(NFCP) and Applicability Study of the Unit Dry-Decontamination Techniques A. Classification of contaminated equipments and characteristics analysis of contaminants B. Applicability study of the unit dry-decontamination techniques 2.Performance Evaluation of Unit Dry Decontamination Technique A. PFC decontamination technique B. CO2 decontamination technique C. Plasma decontamination technique 3.Development of Residual Radiation Assessment Methodology for High Radioactive Facility Decontamination A. Development of radioactive nuclide diffusion model on highly radioactive facility structure B. Obtainment of the procedure for assessment of residual radiation dose 4.Establishment of the Design Concept of Dry Decontamination Process Equipment Applicable to Highly Radioactive Contaminants 5.TRIGA soil unit decontamination technology development A. Development of soil washing and flushing technologies B. Development of electrokinetic soil decontamination technology

  7. WIS decontamination factor demonstration test with radioactive nuclides

    International Nuclear Information System (INIS)

    Kanbe, Hiromi; Mayuzumi, Masami; Ono, Tetsuo; Nagae, Madoka; Sekiguchi, Ryosaku; Takaoku, Yoshinobu.

    1987-01-01

    A radioactive Waste Incineration System (WIS) with suspension combustion is noticed as effective volume reduction technology of low level radiactive wastes that are increasing every year. In order to demonstrate the decontamination efficiency of ceramic filter used on WIS, this test has been carried out with the test facilities as joint research of Central Research Institute of Electric Power Industry (CRIEPI) and Sumitomo Heavy Industries, Ltd. Miscellaneous combustible waste and power resin, to which 5 nuclides (Mn-54, Fe-59, Co-60, Zn-65, Cs-137) were added, were used as samples for incineration. As the result of the test, it was verified that Decontamination Factor (DF) of the single stage ceramic filter was usually kept over 10 5 for every nuclide, and from the results of above DF, over 10 8 is expected for real commercial plant as a total system. Therefore, it is realized that the off-gas clean up system of the WIS composed of only single stage of ceramic filter is capable of sufficiently efficient decontamination of exhaust gas to be released to stack. (author)

  8. Evaluation of high pressure Freon decontamination. I. Preliminary tests

    International Nuclear Information System (INIS)

    Rankin, W.N.

    1983-01-01

    High-pressure Freon blasting techniques are being evaluated for applications involving the removal of non-adherent radioactive particulate contamination at SRP. Very little waste is generated by this technique because the used Freon can be easily distilled and reused. One of the principle advantages of this technique is that decontaminated electrical equipment can be returned to service immediately without drying, unlike high-pressure water blasting techniques. Preliminary scoutin tests evaluating high-pressure Freon blasting for decontamination at SRP were carried out at Quadrex Co., Oak Ridge, TN, October 12 and 13. DWPF-type contamination (raw sludge plus volatiles) and separations area-type contamination (diluted boiling point (47.6 0 C) allow it to rapidly separate from higher boiling contaminants via distillation with filtration to remove particulate material, and distillation with condensation, the solvent may be recovered for indefinite reuse while reducing the radioactive waste to a minimum. 3 references, 5 figures, 6 tables

  9. Changes in the decontamination factor of cesium iodide on evaporation of a scrubbing solution in the Filtered Containment Venting System

    Energy Technology Data Exchange (ETDEWEB)

    Na, Young Su; Ha, Kwang Soon; Kim, Sungil; Cho, Song-Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    When the pressure in the containment building approaches a setting value, the FCVS(Filtered Containment Venting System) operates. The amount of steam and gas mixtures generated during a severe accident can be released into the FCVS. Non-condensable gases and fine aerosols can pass a scrubbing solution and the filters in the FCVS vessel. The decontaminated gases are finally discharged from the FCVS to the outside environment. Previous study observed that a scrubbing solution in the FCVS vessel was constantly evaporating owing to high-temperature steam released continuously from the containment building. A scrubbing solution in the FCVS vessel was completely evaporated at about 31 hours after the FCVS operation. Pool evaporation in the FCVS vessel can negatively affect the decontamination feature of the FCVS because it reduces the scrubbing depth for fission products in an aerosol form. This study carefully evaluated the decontamination factor of metal iodide aerosols especially cesium iodide (CsI), on a scrubbing solution in the FCVS. This paper summarizes the calculated results on the decontamination factor of CsI in the FCVS vessel, which was presented at the international OECD-NEA/NUGENIA-SARNET workshop. This study estimated the decontamination factor of CsI on a scrubbing solution in the FCVS. The MELCOR computer code simulated that an SBO occurred in the OPR 1000. The FCVS consists of a cylindrical vessel with a 3 m diameter and 6.5 m height, and it includes a scrubbing solution of 21 tons. Accumulated mass of CsI aerosol was calculated in a scrubbing solution and the atmosphere in the FCVS vessel and the outside environment. In the early FCVS operation, the decontamination factor of CsI aerosol rapidly increased owing to steam condensation in a scrubbing solution. When the temperature of a pool approached its saturation temperature, the decontamination factor of CsI aerosol started to decrease.

  10. Electropolishing decontamination system for high-level waste canisters

    International Nuclear Information System (INIS)

    Larson, D.E.; Berger, D.N.; Allen, R.P.; Bryan, G.H.; Place, B.G.

    1988-10-01

    As part of a US Department of Energy (DOE) project agreement with the Federal Ministry for Research and Technology (BMFT) in the Federal Republic of Germany (FRG). The Nuclear Waste Treatment Program at the Pacific Northwest Laboratory (PNL) is preparing 30 radioactive canisters containing borosilicate glass for use in high-level waste repository related tests at the Asse Salt Mine. After filling, the canisters will be welded closed and decontaminated in preparation for shipping to the FRG. Electropolishing was selected as the primary decontamination approach, and an electropolishing system with associated canister inspection equipment has been designed and fabricated for installation in a large hot cell. This remote electropolishing system, which is currently undergoing preliminary testing, is described in this report. 3 refs., 3 figs., 1 tab

  11. Evaluation of corrosion inhibitors for high temperature decontamination applications

    International Nuclear Information System (INIS)

    Sathyaseelan, V.S.; Rufus, A.L.; Velmurugan, S.

    2015-01-01

    Normally, chemical decontamination of coolant systems of nuclear power reactors is carried out at temperatures less than 90 °C. At these temperatures, though magnetite dissolves effectively, the rate of dissolution of chromium and nickel containing oxides formed over stainless steel and other non-carbon steel coolant system surfaces is not that appreciable. A high temperature dissolution process using 5 mM NTA at 160 °C developed earlier by us was very effective in dissolving the oxides such as ferrites and chromites. However, the corrosion of structural materials such as carbon steel (CS) and stainless steel (SS) also increased beyond the acceptable limits at elevated temperatures. Hence, the control of base metal corrosion during the high temperature decontamination process is very important. In view of this, it was felt essential to investigate and develop a suitable inhibitor to reduce the corrosion that can take place on coolant structural material surfaces during the high temperature decontamination applications with weak organic acids. Three commercial inhibitors viz., Philmplus 5K655, Prosel PC 2116 and Ferroqest were evaluated at ambient and at 160 °C temperature in NTA formulation. Preliminary evaluation of these corrosion inhibitors carried out using electrochemical techniques showed maximum corrosion inhibition efficiency for Philmplus. Hence, it was used for high temperature applications. A concentration of 500 ppm was found to be optimum at 160 °C and at this concentration it showed an inhibition efficiency of 62% for CS. High temperature dissolution of oxides such as Fe 3 O 4 and NiFe 2 O 4 , which are relevant to nuclear reactors, was also carried out and the rate of dissolution observed was less in the presence of Philmplus. Studies were also carried out to evaluate hydrazine as a corrosion inhibitor for high temperature applications. The results revealed that for CS inhibition efficiency of hydrazine is comparable to that of Philmplus, while

  12. Safety analysis factors for environmental restoration and decontamination and decommissioning

    International Nuclear Information System (INIS)

    Ellingson, D.R.

    1993-04-01

    Environmental restoration (ER) and facility decontamination/decommissioning (D ampersand D) operations can be grouped into two general categories. ''Nonstationary cleanup'' or simply ''cleanup'' activities are where the operation must relocate to the site of new contaminated material at the completion of each task (i.e., the operation moves to the contaminated material). ''Stationary production'' or simply ''production'' activities are where the contaminated material is moved to a centralized location (i.e., the contaminated material is moved to the operation) for analysis, sorting, treatment, storage, and disposal. This paper addresses the issue of nonstationary cleanup design. The following are the specific assigned action items: Collect and compile a list of special safety-related ER/D ampersand D design factors, especially ones that don't follow DOE Order 6430.1A requirements. Develop proposal of what makes sense to recommend to designers; especially consider recommendations for short-term projects. Present proposal at the January meeting. To achieve the action items, applicable US Department of Energy (DOE) design requirements, and cleanup operations and differences from production activities are reviewed and summarized; basic safety requirements influencing design are summarized; and finally, approaches, considerations, and methods for safe, cost-effective design of cleanup activities are discussed

  13. Determination of overall decontamination factors for common impurity elements in PHWR spent fuel reprocessing

    International Nuclear Information System (INIS)

    Pant, D.K.; Bhalerao, B.A.; Gupta, K.K.; Kulkarni, P.G.; Gurba, P.B.; Janardan, P.; Changrani, R.D.; Dey, P.K.

    2009-01-01

    An attempt has been made to determine overall decontamination factors for elemental impurities normally encountered in the U 3 O 8 product obtained by reprocessing of PHWR spent fuel. The solution obtained by dissolution of spent fuel and corresponding U 3 O 8 product were analyzed for 24 elemental impurities by ICP-AES for this purpose. Decontamination factors achieved for major neutron poisons are in the range of 200-400. (author)

  14. Development of high-level radioactive waste treatment and conversion technologies 'Dry decontamination technology development for highly radioactive contaminants'

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Won Zin; Lee, K. W.; Won, H. J.; Jung, C. J.; Choi, W. K.; Kim, G. N.; Moon, J. K

    2001-04-01

    The followings were studied through the project entitled 'Dry Decontamination Technology Development for Highly Radioactive Contaminants'. 1.Contaminant Characteristics Analysis of Domestic Nuclear Fuel Cycle Projects(NFCP) and Applicability Study of the Unit Dry-Decontamination Techniques A. Classification of contaminated equipments and characteristics analysis of contaminants B. Applicability study of the unit dry-decontamination techniques 2.Performance Evaluation of Unit Dry Decontamination Technique A. PFC decontamination technique B. CO2 decontamination technique C. Plasma decontamination technique 3.Development of Residual Radiation Assessment Methodology for High Radioactive Facility Decontamination A. Development of radioactive nuclide diffusion model on highly radioactive facility structure B. Obtainment of the procedure for assessment of residual radiation dose 4.Establishment of the Design Concept of Dry Decontamination Process Equipment Applicable to Highly Radioactive Contaminants 5.TRIGA soil unit decontamination technology development A. Development of soil washing and flushing technologies B. Development of electrokinetic soil decontamination technology.

  15. Improving distillation method and device of tritiated water analysis for ultra high decontamination efficiency

    International Nuclear Information System (INIS)

    Fang, Hsin-Fa; Wang, Chu-Fang; Lin, Chien-Kung

    2015-01-01

    It is important that monitoring environmental tritiated water for understanding the contamination dispersion of the nuclear facilities. Tritium is a pure beta radionuclide which is usually measured by Liquid Scintillation Counting (LSC). The average energy of tritum beta is only 5.658 keV that makes the LSC counting of tritium easily be interfered by the beta emitted by other radionuclides. Environmental tritiated water samples usually need to be decontaminated by distillation for reducing the interference. After Fukushima Nucleaer Accident, the highest gross beta concentration of groundwater samples obtained around Fukushima Daiichi Nuclear Power Station is over 1,000,000 Bq/l. There is a need for a distillation with ultra-high decontamination efficiency for environmental tritiated water analysis. This study is intended to improve the heating temperature control for better sub-boiling distillation control and modify the height of the container of the air cooling distillation device for better fractional distillation effect. The DF of Cs-137 of the distillation may reach 450,000 which is far better than the prior study. The average loss rate of the improved method and device is about 2.6% which is better than the bias value listed in the ASTM D4107-08. It is proven that the modified air cooling distillation device can provide an easy-handling, water-saving, low cost and effective way of purifying water samples for higher beta radionuclides contaminated water samples which need ultra-high decontamination treatment. - Highlights: • The improvements of method and device make the decontaminatin factor (DF) of Cs-137 of distillation reach over 450,000. • The decontamination factor ( DF) value may be increased about 20 times by increasing the height of the container from 7 cm to 20 cm. • The device provides an easy-handling, water-saving, low cost, stable and effective way for the distillation of triated water analysis.

  16. Evaluation of Decontamination Factor of Aerosol in Pool Scrubber according to Bubble Shape and Size

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Hyun Joung; Ha, Kwang Soon; Jang, Dong Soon [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The scrubbing pool could play an important role in the wet type FCVS because a large amount of aerosol is captured in the water pool. The pool scrubbing phenomena have been modelled and embedded in several computer codes, such as SPARC (Suppression Pool Aerosol Removal Code), BUSCA (BUbble Scrubbing Algorithm) and SUPRA (Suppression Pool Retention Analysis). These codes aim at simulating the pool scrubbing process and estimating the decontamination factors (DFs) of the radioactive aerosol and iodine gas in the water pool, which is defined as the ratio of initial mass of the specific radioactive material to final massy after passing through the water pool. The pool scrubbing models were reviewed and an aerosol scrubbing code has been prepared to calculate decontamination factor through the pool. The developed code has been verified using the experimental results and parametric studies the decontamination factor according to bubble shape and size. To evaluate the decontamination factor more accurate whole pool scrubber phenomena, the code was improved to consider the variety shape and size of bubbles. The decontamination factor were largely evaluated in ellipsoid bubble rather than in sphere bubble. The pool scrubbing models will be enhanced to apply more various model such as aerosol condensation of hygroscopic. And, it is need to experiment to measure to bubble shape and size distribution in pool to improve bubble model.

  17. Reuse of waste water from high pressure water jet decontamination for reactor decommissioning scrap metal

    International Nuclear Information System (INIS)

    Deng Junxian; Li Xin; Hou Huijuan

    2011-01-01

    For recycle and reuse of reactor decommissioning scrap metal by high pressure water jet decontamination, large quantity of radioactive waste water will be generated. To save the cost of radioactive waste water treatment and to reduce the cost of the scrap decontamination, this part of radioactive waste water should be reused. Most of the radioactivities in the decontamination waste water come from the solid particle in the water. Thus to reuse the waste water, the solid particle in the waster should be removed. Different possible treatment technologies have been investigated. By cost benefit analysis the centrifugal separation technology is selected. (authors)

  18. Decontamination factor of the commercial detergents for the skin (part 3)

    Energy Technology Data Exchange (ETDEWEB)

    Miyabe, Kenjiro; Takasaki, Koji [Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan); Yasunaka, Hideo; Izumi, Yuichi [Japan Environment Research Corporation, Tokyo (Japan)

    2000-08-01

    The commercial detergents, which are cleansing cream, shampoo, neutral detergent, etc., were examined in order to select the body cleaners that are substitutes for the titanium dioxide paste. JNC entrusted Japan Environment Research Corporation Limited with these examinations since 1997. In 1997 and 1998, the commercial detergents were examined for Ce-144, Cs-137 and Ru-106. In 1999, 22 detergents were examined for Co-60 from the result of the past examinations. In this examination, the radioactive solution of Co-60 was dropped on the pig-skin samples. These samples were washed with each detergent after 5 minutes and 40 minutes. The decontamination factors of detergents were estimated by the radioactive ratio of the samples before and after washing. As a result of this examination, the decontamination factors for Co-60 was the same as the decontamination factors for Ce-144 and Cs-137, and 11 detergents were nominated as the cleaner that have the decontamination factor more than that of titanium dioxide paste. (author)

  19. Factors of skin decontamination as derived from experimental studies

    International Nuclear Information System (INIS)

    Pratzel, H.G.

    1992-01-01

    The processes occuring during radioactive contamination of the skin are reminiscent of those observed in connection with skin penetration by drugs. Explained are the laws determining the penetration of substances through the skin surface, their spreading between the corneocystes into the deeper layers of the stratum corneum and their final concentrations, the decrease of which with the depth of the corneal layer can be described by an exponential curve. The extent to which the penetrating substances are transferred from the solvent to the corneal layer's lipid phase depends on their relative solubility. The intercellular lipid layer in the lower third of the stratum corneum creates the greatest obstacle to permeation through the skin. The lipid content in this part of the corneal layer is seen to be inversely proportional to the degree of natural barrier dysfunction and, thus, to permeation. For measurements of skin permeation, experiments were performed in young pigs using aqueous radioactive solutions. Part of the substances penetrated into the organism through the follicles, where the corneal layer is more permeable. In cases of very hairy skin the amount of substance deposited as a result of additional follicle penetration is seen to be higher. The greatest proportion of radioactivity by far is taken up into the stratum corneum, while only little is seen to reach the follicles and even less the deeper layers of the skin. Decontamination of the skin cannot be carried out for areas beyond the boundary of the corneal layer. (orig./HP) [de

  20. Impact of Cesium decontamination on performances of high activity sample analysis

    Energy Technology Data Exchange (ETDEWEB)

    Maillard, Christophe; Boyer-Deslys, Valerie; Dautheribes, Jean L.; Esbelin, Eric; Beres, Andre; Jan, Steve; Baghdadi, Sarah; Rivier, Cedric [CEA, Nuclear Energy Division, Bagnols sur Ceze (France). RadioChemistry and Processes Dept.

    2017-09-01

    Experiments in the ATALANTE facility can lead to high activity samples (for example the dissolution of hulls and spent fuels), essentially coming from the presence of {sup 137}Cs. Usually, these samples are handled in a shielded cell. The removal of this radionuclide from the sample would make it possible to handle it in glove boxes without having to perform an important dilution in the shielded cells beforehand. It would allow to analyze samples using techniques usually implemented in glove boxes (such as ICP, α spectrometry..) and to reach lower detection and quantification limits. To do so, a separation by extraction chromatography using a Triskem AMP-PAN column was developed. A cesium decontamination factor higher than 5 x 10{sup 4} and detection limits improvement up to a factor 100 were obtained.

  1. Development of aerosol decontamination factor evaluation method for filtered containment venting system

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae bong; Kim, Sung Il; Jung, Jaehoon; Ha, Kwang Soon; Kim, Hwan Yeol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    Fission products would be released from molten corium pools which are relocated into the lower plenum of reactor pressure vessel, on the concrete pit and in the core catcher. In addition, steam, hydrogen and noncondensable gases such as CO and CO2 are generated during the core damage progression due to loss of coolant and the molten core-concrete interaction. Consequently, the pressure inside the containment could be increased continuously. Filtered containment venting is one action to prevent an uncontrolled release of radioactive fission products caused by an overpressure failure of the containment. After the Fukushima-Daiichi accident which was demonstrated the containment failure, many countries to consider the implementation of filtered containment venting system(FCVS) on nuclear power plant where these are not currently applied. In general evaluation for FCVS is conducted to determine decontamination factor on several conditions (aerosol diameter, submergence depth, water temperature, gas flow, steam flow rate, pressure, operating time,...). It is essential to quantify the mass concentration before and after FCVS for decontamination factor. This paper presents the development of the evaluation facility for filtered containment venting system at KAERI and an experimental investigation for aerosol removal performance. Decontamination factor for the FCVS is determined by filter measurement. The result of the aerosol size distribution measurement shows the aerosol removal performance by an aerosol size.

  2. Specific decontamination methods: water nozzle, cavitation erosion

    International Nuclear Information System (INIS)

    Boulitrop, D.; Gauchon, J.P.; Lecoffre, Y.

    1984-05-01

    The erosion and decontamination tests carried out in the framework of this study, allowed to specify the fields favourable to the use of the high pressure jet taking into account the determinant parameters that are the pressure and the target-nozzle distance. The previous spraying of gels with chemical reagents (sulfuric acid anf hydrazine) allows to get better decontamination factors. Then, the feasibility study of a decontamination method by cavitation erosion is presented. Gelled compounds for decontamination have been developed; their decontamination quality has been evaluated by comparative contamination tests in laboratory and decontamination tests of samples of materials used in nuclear industry; this last method is adapted to remote handling devices and produces a low quantity of secondary effluents, so it allows to clean high contaminated installation on the site without additional exposure of the personnel [fr

  3. An electrochemical and high-speed imaging study of micropore decontamination by acoustic bubble entrapment.

    Science.gov (United States)

    Offin, Douglas G; Birkin, Peter R; Leighton, Timothy G

    2014-03-14

    Electrochemical and high-speed imaging techniques are used to study the abilities of ultrasonically-activated bubbles to clean out micropores. Cylindrical pores with dimensions (diameter × depth) of 500 μm × 400 μm (aspect ratio 0.8), 125 μm × 350 μm (aspect ratio 2.8) and 50 μm × 200 μm (aspect ratio 4.0) are fabricated in glass substrates. Each pore is contaminated by filling it with an electrochemically inactive blocking organic material (thickened methyl salicylate) before the substrate is placed in a solution containing an electroactive species (Fe(CN)6(3-)). An electrode is fabricated at the base of each pore and the Faradaic current is used to monitor the decontamination as a function of time. For the largest pore, decontamination driven by ultrasound (generated by a horn type transducer) and bulk fluid flow are compared. It is shown that ultrasound is much more effective than flow alone, and that bulk fluid flow at the rates used cannot decontaminate the pore completely, but that ultrasound can. In the case of the 125 μm pore, high-speed imaging is used to elucidate the cleaning mechanisms involved in ultrasonic decontamination and reveals that acoustic bubble entrapment is a key feature. The smallest pore is used to explore the limits of decontamination and it is found that ultrasound is still effective at this size under the conditions employed.

  4. Guideline values for skin decontamination measures based on nuclidspecific dose equivalent rate factors

    International Nuclear Information System (INIS)

    Pfob, H.; Heinemann, G.

    1992-01-01

    Corresponding dose equivalent rate factors for various radionuclides are now available for determining the skin dose caused by skin contamination. These dose equivalent rate factors take into account all contributions from the types of radiation emitted. Any limits for skin decontamination measures are nowhere contained or determined yet. However, radiological protection does in practice require at least guideline values in order to prevent unsuitable or detrimental measures that can be noticed quite often. New calculations of dose equivalent rate factors for the skin now make the recommendation of guideline values possible. (author)

  5. Radioactive decontamination

    International Nuclear Information System (INIS)

    1983-07-01

    This Code of Practice covers: (a) the decontamination of plant items, buildings and associated equipment; (b) decontamination of protective clothing; (c) simple personal decontamination; and (d) the basic mechanisms of contamination and their influence on decontaminability. (author)

  6. The state of the art on the dry decontamination technologies applicable to highly radioactive contaminants and their needs for the national nuclear fuel cycle developent

    International Nuclear Information System (INIS)

    Oh, Won Zin; Lee, K. W.; Won, H. J.; Jung, C. H.; Chol, W. K.; Kim, G. N.; Moon, J. K.

    2000-12-01

    This report is intended to establish their needs to support the dry decontamination activities applicable to highly radioactive contaminants based on the requirement of technologies development suggested from the national nuclear fuel cycle projects, such as DUPIC, advanced spent fuel management and long-lived radionuclides conversion. The technology needs associated with decontamination addressed the requirements associated with the efficiency of decontamination technology, the reduction of secondary wastes, applicabilities and the remote operation. And also, Characterization and decontamination technologies for various contaminants are reviewed and analysed. Based on the assessment, Unit dry decontamination processes are selected and the schematic flow diagram for decontamination of highly radioactive contaminants

  7. The state of the art on the dry decontamination technologies applicable to highly radioactive contaminants and their needs for the national nuclear fuel cycle developent

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Won Zin; Lee, K.W.; Won, H.J.; Jung, C.H.; Chol, W.K.; Kim, G.N.; Moon, J.K

    2000-12-01

    This report is intended to establish their needs to support the dry decontamination activities applicable to highly radioactive contaminants based on the requirement of technologies development suggested from the national nuclear fuel cycle projects, such as DUPIC, advanced spent fuel management and long-lived radionuclides conversion. The technology needs associated with decontamination addressed the requirements associated with the efficiency of decontamination technology, the reduction of secondary wastes, applicabilities and the remote operation. And also, Characterization and decontamination technologies for various contaminants are reviewed and analysed. Based on the assessment, Unit dry decontamination processes are selected and the schematic flow diagram for decontamination of highly radioactive contaminants.

  8. Tests for improvement of decontamination factors on RWTP technological line of precipitation

    International Nuclear Information System (INIS)

    Popovici, C.

    1998-01-01

    Low and intermediate level radioactive wastes are produced from diverse applications of radionuclides and radioactive materials in industry, medicine, agriculture and research. Many of the liquid wastes need treatment for safe management. Chemical precipitation process is well established for the removal of radioactive from LLW and ILW. The precipitation of insoluble compounds is one of the oldest and most used process for the treatment of aqueous waste. The precipitation can be performed either in a simple step or by combined chemical treatment which mainly includes as radioactive carries iron oxo-hydroxides, iron phosphate, calcium phosphate and cooper ferrocyanide. The contaminants are removed from LLW and ILW during precipitation by different mechanisms such as: coagulation and flocculation process, precipitation and co-precipitation, adsorption on the coagulant aid, ion exchange and physical enmeshment by coagulant aid. All these processes are directly dependent on the precipitate properties and its structure which are connected with the initial system composition and the precipitation procedure. Chemical precipitation method for treatment of LLW and ILW by co-precipitation of caesium with cooper ferrocyanide was employed on the real radioactive wastes where the volumes were 3 m 3 , 24 m 3 and 30 m 3 . The percentage removals of Cs-137 from 2285 Bq, 1310 Bq and 1232 Bq per litre of real effluents were 98.8%, 98.9% and 99.1%, respectively. Test runs for removal of Cs-137 from the wastes varied from 90% to 95%. High decontamination factors were observed in the pH range of 9 to 10.5. (author)

  9. On-line, real-time measurements of decontamination factors for a low-level waste incinerator

    International Nuclear Information System (INIS)

    Close, D.A.; Draper, W.E.

    1982-01-01

    A method is described to monitor the distribution of radioactive isotopes through the off-gas treatment system of an incinerator. Simulated commercial waste spiked with known amounts of five fission products, 131 I, 106 Ru, 137 Cs, 59 Fe, 60 Co, were incinerated. High resolution photon detectors were installed on the off-gas handling system of the controlled air incinerator at the Los Alamos National Laboratory to determine relative decontamination factors, which ranged from a low of 40 for 137 Cs to a high of 50O0 for 131 I. Background measurements were made to determine the residual activity in the incinerator. Due to the constant purging of the system to maintain a negative pressure with respect to the surrounding environment, the residual activity decays more rapidly than dictated by its half-life. (orig.)

  10. Environmental decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Cristy, G.A.; Jernigan, H.C. (eds.)

    1981-02-01

    The record of the proceedings of the workshop on environmental decontamination contains twenty-seven presentations. Emphasis is placed upon soil and surface decontamination, the decommissioning of nuclear facilities, and assessments of instrumentation and equipment used in decontamination. (DLS)

  11. Environmental decontamination

    International Nuclear Information System (INIS)

    Cristy, G.A.; Jernigan, H.C.

    1981-02-01

    The record of the proceedings of the workshop on environmental decontamination contains twenty-seven presentations. Emphasis is placed upon soil and surface decontamination, the decommissioning of nuclear facilities, and assessments of instrumentation and equipment used in decontamination

  12. Characterization of decontamination factors for evaporators used in the treatment of low and intermediate level liquid radioactive wastes

    International Nuclear Information System (INIS)

    Rood, L.B.; Law, C.G. Jr.

    1972-01-01

    Evaporator decontamination factors were studied as functions of boiloff rate, volume reduction, and feed pH. A bench-scale vertical tube evaporator operating on simulated intermediate level nuclear wastes was used. Decontamination factors were not found to be strong functions of volume reduction or boiloff below vapor velocities of 25 lb/ft 2 -hr. At higher vapor fluxes, splashing was encountered. Foaming occurred at a feed pH of 6 but not at higher values. The presence of radioisotopes in the feed had no effect on evaporator performance

  13. The study for decontamination techniques of adhered high contamination on protective clothing

    Energy Technology Data Exchange (ETDEWEB)

    Park, Dong Won; Kim, Byung Rae; Kim, Seung Jae [Korea Inspection Co., ltd., Kimhae (Korea, Republic of)

    2013-04-15

    Nuclear power plant worker who work at Radiation access control area should be take the protective clothing that basically maintained in accordance with the provisions of under 40KBq / m{sup 3} to prevent contamination of the worker. However, the highly contaminated work clothes that occurs after each planned preventive maintenance of nuclear power plants reaches too many quantities even if not only through the process of re-washing several times and but also through the process of decay. This lead to the increase of radioactive waste and there is also concern dose exposure due to the dose that occurs in the process of storage for radioactive decay. So research of fixation contaminated protective clothing decontamination technology seems to contribute significantly reduction of radioactive waste depend on the reuse of highly contaminated protective clothing that ensured soundness. High-contamination protective clothing are generated by planned preventive maintenance of each nuclear power plant. Despite repeated re-laundry, radioactive contamination can not be removed, must be selected a disposal. These, thought to be impossible virtually decontamination for a long time but through the decontamination method of this paper, quantity of disposal protective clothing is to be able to significantly reduce.

  14. Determination of vapor-liquid equilibrium data and decontamination factors needed for the development of evaporator technology for use in volume reduction of radioactive waste streams

    International Nuclear Information System (INIS)

    Betts, S.E.

    1993-01-01

    A program is currently in progress at Argonne National Laboratory to evaluate and develop evaporator technology for concentrating radioactive waste streams. By concentrating radioactive waste streams, disposal costs can be significantly reduced. To effectively reduce the volume of waste, the evaporator must achieve high decontamination factors so that the distillate is sufficiently free of radioactive material. One technology that shows a great deal of potential for this application is being developed by LICON, Inc. In this program, Argonne plans to apply LICON's evaporator designs to the processing of radioactive solutions. Concepts that need to be incorporated into the design of the evaporator include, criticality safety, remote operation and maintenance, and materials of construction. To design an effective process for concentrating waste streams, both solubility and vapor-liquid equilibrium data are needed. The key issue, however, is the high decontamination factors that have been demonstrated by this equipment. Two major contributions were made to this project. First, a literature survey was completed to obtain available solubility and vapor-liquid equilibrium data. Some vapor-liquid data necessary for the project but not available in the literature was obtained experimentally. Second, the decontamination factor for the evaporator was determined using neutron activation analysis (NAA)

  15. Decontamination Technology Development for Nuclear Research Facilities

    International Nuclear Information System (INIS)

    Choi, W. K.; Jung, C. H.; Oh, W. Z.

    2007-06-01

    The originative CO 2 pellet blasting equipment was developed by improving additional components such as feed screw, idle roller and air-lock feeder to clear up the problems of freezing and discontinuity of blasting and by adopting pneumatically operated vacuum suction head and vacuum cup to prevent recontamination by collecting contaminant particulates simultaneously with the decontamination. The optimum decontamination process was established according to the kind of materials such as metal, concrete and plastic and the type of contaminants such as particulate, fixed chemical compound and oil. An excellent decontamination performances were verified by means of the lab-scale hot test with radioactive specimen and the technology demonstration in IMEF hot cell. The PFC dry decontamination equipment applicable to the surface contaminated with high radioactive particulate was developed. This equipment consists of the unit processes such as spray, collection, filtration and dry distillation designed originatively applicable to inside of dry hot cell. Through the demonstration of PFC spray decontamination process in IMEF hot cell, we secured on-site applicability and the decontamination efficiency more than 90 %. We investigated the characteristics of dismantled metal waste melting and the radionuclide(Co, Cs, U) distribution into ingot and slag by melting decontamination experiments using electric arc melter. We obtained the decontamination factors greater than 100 for Cs and of 10∼100 for uranium. The pilot scale(200 kg/batch) demonstration for melting decontamination was carried out successfully using high temperature melting facility at KAERI. The volume reduction factor of 1/7 and the economical feasibility of the melting decontamination were verified.

  16. Testing and evaluation of eight decontamination chemicals

    International Nuclear Information System (INIS)

    Demmer, R.

    1994-09-01

    This report covers experimental work comparing eight different decontamination chemicals. Seven of these chemicals have some novelty, or are not currently in use at the ICPP. The eighth is a common ICPP decontamination reagent used as a baseline for effective comparison. Decontamination factors, waste generation values, and corrosion rates are tabulated for these chemicals. Recommendations are given for effective methods of non-sodium or low-sodium decontamination chemicals. The two most effective chemical for decontamination found in these test were a dilute hydrofluoric and nitric acid (HF/HNO 3 ) mixture and a fluoroboric acid solution. The fluoroboric acid solution (1 molar) was by far the most effective decontamination reagent, but suffered the problem of generating significant final calcine volume. The HF/HNO 3 solution performed a very good decontamination of the SIMCON coupons while generating only small amounts of calcine volume. Concentration variables were also tested, and optimized for these two solutions. Several oxidation/reduction decon chemical systems were also tested. These systems were similar to the TURCO 4502 and TURCO 4521 solutions used for general decontamination at the ICPP. A low sodium alternative, nitric acid/potassium permanganate, to the ''high sodium'' TURCO 4502 was tested extensively, optimized and recommended for general ICPP use. A reductive chemical solution, oxalic acid/nitric acid was also shown to have significant advantages

  17. Advanced Decontamination Technologies: High Hydrostatic Pressure on Meat Products

    Science.gov (United States)

    Garriga, Margarita; Aymerich, Teresa

    The increasing demand for “natural” foodstuffs, free from chemical additives, and preservatives has triggered novel approaches in food technology developments. In the last decade, practical use of high-pressure processing (HPP) made this emerging non-thermal technology very attractive from a commercial point of view. Despite the fact that the investment is still high, the resulting value-added products, with an extended and safe shelf-life, will fulfil the wishes of consumers who prefer preservative-free minimally processed foods, retaining sensorial characteristics of freshness. Moreover, unlike thermal treatment, pressure treatment is not time/mass dependant, thus reducing the time of processing.

  18. A decontamination technique for decommissioning waste

    International Nuclear Information System (INIS)

    Heki, H.; Hosaka, K.; Kuribayashi, N.; Ishikura, T.

    1993-01-01

    A large amount of radioactive metallic waste is generated from decommissioned commercial nuclear reactors. It is necessary from the point of environmental protection and resource utilization to decontaminate the contaminated metallic waste. A decommissioning waste processing system has been previously proposed considering such decommissioning waste characteristics as its large quantity, large radioactivity range, and various shapes and materials. The decontamination process in this system was carried out by abrasive blasting as pretreatment, electrochemical decontamination as the main process, and ultrasonic cleaning in water as post-treatment. For electrochemical decontamination, electrolytic decontamination for simple shaped waste and REDOX decontamination for complicated shaped waste were used as effective decontamination processing. This time, various kinds of actual radioactive contaminated samples were taken from operating power plants to simulate the decontamination of decommissioning waste. After analyzing the composition, morphogenesis and surface observation, electrolytic decontamination, REDOX decontamination, and ultrasonic cleaning experiments were carried out by using these samples. As a result, all the samples were decontaminated below the assumed exemption level(=4 x 10 -2 Bq/g). A maximum decontamination factor of over 104 was obtained by both electrolytic and REDOX decontamination. The stainless steel sample was easy to decontaminate in both electrochemical decontaminations because of its thin oxidized layer. The ultrasonic cleaning process after electrochemical decontamination worked effectively for removing adhesive sludge and the contaminated liquid. It has been concluded from the results mentioned above that electrolytic decontamination and REDOX decontamination are effective decontamination process for decontaminating decommissioning waste

  19. Decontamination of radioactive isotopes

    International Nuclear Information System (INIS)

    Despotovic, R.; Music, S.; Subotic, B.; Wolf, R.H.H.

    1979-01-01

    Removal of radioactive isotopes under controlled conditions is determined by a number of physical and chemical properties considered radiocontaminating and by the characteristics of the contaminated object. Determination of quantitative and qualitative factors for equilibrium in a contamination-decontamination system provides the basis for rational and successful decontamination. The decontamination of various ''solid/liquid'' systems is interesting from the scientific and technological point of view. These systems are of great importance in radiation protection (decontamination of various surfaces, liquids, drinking water, fixation or collection of radiocontaminants). Different types of decontamination systems are discussed. The dependence of rate and efficiency of the preparation conditions and on the ageing of the scavenger is described. The influence of coagulating electrolyte on radioactive isotope fixation efficiency was also determined. The fixation of fission radionuclide on oxide scavengers has been studied. The connection between fundamental investigations and practical decontamination of the ''solid/liquid'' systems is discussed. (author)

  20. Factors determining the stainless steel decontamination efficiency for the steam generator heat exchanger tubes at NPPs with the WWERs

    International Nuclear Information System (INIS)

    Kamenskij, A.N.; Balaban-Irmenin, Yu.V.

    1983-01-01

    To raise the efficiency of the redox method and decrease the amount of radioactive wastes, a possibility of improving the decontamination process for NPP heat exchanger tubes made of stainless steel is studied. In the home practice the redox method of equipment decontamination is carried out as a multi-cycle process. In each cycle the surface is treated first with a permanganate alkaline solution ther with an oxalic acid solution, with a condensate washing-at between the treatments. Using samples cut out of the steam generator pipelines of the first and third power units of the Novovoronezh NPP the effect of the oXalic acid concentration, as well as washout time and conditions on the decontamination factor are studied. On the basis of analysis of the obtained data a conclusion is drawn that using oxalic acid of low concentrations and increasing its concentrations from cycle to cycle maximum decontamination factor values can be obtained at a minimum salt content in radioactive wastes

  1. Gross decontamination experiment report

    International Nuclear Information System (INIS)

    Mason, R.; Kinney, K.; Dettorre, J.; Gilbert, V.

    1983-07-01

    A Gross Decontamination Experiment was conducted on various levels and surfaces of the TMI - Unit 2 reactor building in March 1982. The polar crane, D-rings, missile shields, refueling canals, refueling bridges, equipment, and elevations 305' and 347'-6'' were flushed with low pressure water. Additionally, floor surfaces on elevation 305' and floor surfaces and major pieces of equipment on elevation 347'-6'' were sprayed with high pressure water. Selective surfaces were decontaminated with a mechanical scrubber and chemicals. Strippable coating was tested and evaluated on equipment and floor surfaces. The effectiveness, efficiency, and safety of several decontamination techniques were established for the large, complex decontamination effort. Various decontamination equipment was evaluated and its effectiveness was documented. Decontamination training and procedures were documented and evaluated, as were the support system and organization for the experiment

  2. Gross decontamination experiment report

    Energy Technology Data Exchange (ETDEWEB)

    Mason, R.; Kinney, K.; Dettorre, J.; Gilbert, V.

    1983-07-01

    A Gross Decontamination Experiment was conducted on various levels and surfaces of the TMI - Unit 2 reactor building in March 1982. The polar crane, D-rings, missile shields, refueling canals, refueling bridges, equipment, and elevations 305' and 347'-6'' were flushed with low pressure water. Additionally, floor surfaces on elevation 305' and floor surfaces and major pieces of equipment on elevation 347'-6'' were sprayed with high pressure water. Selective surfaces were decontaminated with a mechanical scrubber and chemicals. Strippable coating was tested and evaluated on equipment and floor surfaces. The effectiveness, efficiency, and safety of several decontamination techniques were established for the large, complex decontamination effort. Various decontamination equipment was evaluated and its effectiveness was documented. Decontamination training and procedures were documented and evaluated, as were the support system and organization for the experiment.

  3. Development of decontamination methods

    International Nuclear Information System (INIS)

    Kunze, S.; Dippel, T.; Hentschel, D.

    1976-01-01

    PVC floorings, fabricated by mixing of the basic components, showed no relation between content of fillers and decontamination results. Decontamination results are partly poorer, if the flooring contains a high concentration of the filler, especially if the latter consists mainly of hydrophilic materials. The coloring of the floorings seems to have no influence on the decontamination. Rubber floorings, fabricated by chemical reactions between polymers, vulcanization materials and fillers, show decontamination results depending definitely from the proper choice of the filler. Flooring types, containing lampblack, graphite, kaoline, barium sulfate and titanium oxide are easy to decontaminate. Increasing contents of hydrophilic filler cause a fall off in the decontamination results. The decontamination effectiveness and the homogenity of cleaning pastes based on hydrochloric acid, nitric acid, titanium oxide and polyethylene powders is strongly depended on the content of hydrochloric acid. Reduction of the content of this component to less than 2 w/O remains the effectiveness unchanged only if the titanium oxide-polyethylene powder mixture is substituted by a high density, highly surface active powder material. This type of paste containing no hydrochloric acid shows nearly the same decontamination effectiveness as standard pickling pastes containing about 30% hydrochlorid acid. Properly prepared salt powder turn out to be easily and successfully applied to metal surfaces by a flame spray technique. The thin layer of molten salts is a very effective decontamination to samples contaminated in the primary loop of a PWR. (orig.) [de

  4. Decontamination of main coolant pumps

    International Nuclear Information System (INIS)

    Roofthooft, R.

    1988-01-01

    Last year a number of main coolant pumps in Belgian nuclear power plants were decontaminated. A new method has been developed to reduce the time taken for decontamination and the volume of waste to be treated. The method comprises two phases: Oxidation with permanganate in nitric acid and dissolution in oxalic acid. The decontamination of main coolant pumps can now be achieved in less than one day. The decontamination factors attained range between 15 and 150. (orig.) [de

  5. Precipitation process for supernate decontamination

    International Nuclear Information System (INIS)

    Lee, L.M.; Kilpatrick, L.L.

    1982-11-01

    A precipitation and adsorption process has been developed to remove cesium, strontium, and plutonium from water-soluble, high-level radioactive waste. An existing waste tank serves as the reaction vessel and the process begins with the addition of a solution of sodium tetraphenylborate and a slurry of sodium titanate to the contained waste salt solution. Sodium tetraphenylborate precipitates the cesium and sodium titanate adsorbs the strontium and plutonium. The precipitate/adsorbate is then separated from the decontaminated salt solution by crossflow filtration. This new process offers significant capital savings over an earlier ion exchange process for salt decontamination. Chemical and small-scale engineering studies with actual waste are reported. The effect of many variables on the decontamination factors and filter performance are defined

  6. Decontamination of stainless steel canisters that contain high-level waste

    International Nuclear Information System (INIS)

    Bray, L.A.

    1987-01-01

    At the West Valley Nuclear Services Company (WVNSC) in West Valley, New York, high-level radioactive waste (HLW) will be vitrified into a borosilicate glass form and poured into large, stainless steel canisters. During the filling process, volatile fission products, principally 137 Cs, condense on the exterior of the canisters. The smearable contamination that remains on the canisters after they are filled and partially cooled must be removed from the canisters' exterior surfaces prior to their storage and ultimate shipment to a US Department of Energy (DOE) repository for disposal. A simple and effective method was developed for decontamination of HLW canisters. This method of chemical decontamination is applicable to a wide variety of contaminated equipment found in the nuclear industry. The process employs a reduction-oxidation system [Ce(III)/Ce(IV)] in nitric acid solution to chemically mill the surface of stainless steel, similar to the electropolishing process, but without the need for an applied electrical current. Contaminated canisters are simply immersed in the solution at controlled temperature and Ce(IV) concentration levels

  7. Role of alkyl alcohol on viscosity of silica-based chemical gels for decontamination of highly radioactive nuclear facilities

    International Nuclear Information System (INIS)

    Choi, B. S.; Yoon, S. B.; Jung, C. H.; Lee, K. W.; Moon, J. K.

    2012-01-01

    Silica-based chemical gel for the decontamination of nuclear facilities was prepared by using fumed silica as a viscosifier, a 0.5 M Ce (IV) solution dissolved in concentrated nitric acid as a chemical decontamination agent, and tripropylene glycol butyl ether (TPGBE) as a co-viscosifier. A new effective strategy for the preparation of the chemical gel was investigated by introducing the alkyl alcohols as organic solvents to effectively dissolve the co-viscosifier. The mixture solution of the co-viscosifier and alkyl alcohols was more effective in the control of viscosity than that of the co-viscosifier only in gel. Here, the alkyl alcohols played a key role as an effective dissolution solvent for the co-viscosifier in the preparation of the chemical gel, resulting in a reducing of the amount of the co-viscosifier and gel time compared with that of the chemical gel prepared without the alkyl alcohols. It was considered that the alkyl alcohols contributed to the effective dissolution of the co-viscosifier as well as the homogeneous mixing in the formation of the gel, while the co-viscosifier in an aqueous media of the chemical decontamination agent solution showed a lower solubility. The decontamination efficiency of the chemical gels prepared in this work using a multi-channel analyzer (MCA) showed a high decontamination efficiency of over ca. 94% and ca. 92% for Co-60 and Cs-137 contaminated on surface of the stainless steel 304, respectively. (authors)

  8. Decontamination possibilities of high-toxic wastes by means of dense plasma generators

    International Nuclear Information System (INIS)

    Rutberg, P.G.; Kolikov, V.A.; Bogomaz, A.A.; Budin, A.V.

    1997-01-01

    In present time the idea of plasma generators application for the high-toxic agents and wastes decontamination has become very urgent. It is known that chemical bonds energy of some molecules being part of these substances is so high that it is impossible to destroy them using traditional methods. Taking into account the fact that the temperature of plasma generator's arc column may be of tens eV, and its energy of hundreds kJ, one may state that any known chemical substances taken in quite large amount, may be dissociated to the atoms. In this paper simplified construction of plasma generator and technological scheme of plasmachemical installation are presented. (author)

  9. Separations canyon decontamination facilities

    International Nuclear Information System (INIS)

    Hershey, J.H.

    1975-01-01

    Highly radioactive process equipment is decontaminated at the Savannah River Plant in specially equipped areas of the separations canyon building so that direct mechanical repairs or alterations can be made. Using these facilities it is possible to decontaminate and repair equipment such as 10- x 11-ft storage tanks, 8- x 8-ft batch evaporator pots and columns, 40-in. Bird centrifuges, canyon pumps and agitators, and various canyon piping systems or ''jumpers.'' For example, centrifuge or evaporator pots can be decontaminated and rebuilt for about 60 percent of the 1974 replacement cost. The combined facilities can decontaminate and repair 6 to 10 pieces of major equipment per year. Decontamination time varies with type of equipment and radioactivity levels encountered

  10. Separations canyon decontamination facilities

    International Nuclear Information System (INIS)

    Hershey, J.H.

    1975-05-01

    Highly radioactive process equipment is decontaminated at the Savannah River Plant in specially equipped areas of the separations canyon buildings so that direct mechanical repairs or alterations can be made. Using these facilities it is possible to decontaminate and repair equipment such as 10- x 11-ft storage tanks, 8- x 8-ft batch evaporator pots and columns, 40-in. Bird centrifuges, canyon pumps and agitators, and various canyon piping systems or ''jumpers.'' For example, centrifuge or evaporator pots can be decontaminated and rebuilt for about 60 percent of the 1974 replacement cost. The combined facilities can decontaminate and repair 6 to 10 pieces of major equipment per year. Decontamination time varies with type of equipment and radioactivity levels encountered. (U.S.)

  11. Decontamination factor Improvement and Waste Reduction of Full-scaled Evaporation System for Liquid Radioactive Waste Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Tae; Ju, Young Jong; Seol, Jeung Gun; Cho, Nam Chan [KNF, Daejeon (Korea, Republic of); Ha, Dong Hwan; Kim, Yun Kwan [Jeontech Co., Suwon (Korea, Republic of)

    2016-05-15

    Liquid radioactive waste is produced from nuclear power plants, nuclear research centers, radiopharmaceuticals and nuclear fuel fabrication plants, etc. Ion-exchange, chemical precipitation, evaporation, filtration, liquid/solid extraction and centrifugal are applied to treat the liquid waste. Chemical precipitation requires low capital and operation cost. However, it produces large amount of secondary waste and has low DF (decontamination factor). Evaporation process removes variety of radionuclides in high DF. But, it also has problems in scaling and foaming [3, 4]. In this study, it is investigated that the effect of switching lime precipitation and centrifugal processes to evaporation system for improvement of removal efficiency and decrease of waste in full-scaled radioactive wastewater treatment plant. By swapping full-scaled wastewater treatment system from the centrifugal and the lime precipitation to the evaporator and the crystallizer in the nuclear fuel fabrication plant, it was possible to increase removal efficiency and to minimize waste productivity. Radioactivity concentration of effluent is decreased from 0.01 Bq/mL to ND level. Besides, waste production was reduced from 15 drums/yr to 2 drums/yr (87%).

  12. Determination of halogen content in glass for assessment of melter decontamination factors

    International Nuclear Information System (INIS)

    Goles, R.W.

    1996-03-01

    Melter decontamination factor (DF) values for the halogens (fluorine, chlorine, and iodine) are important to the Hanford Waste Vitrification Plant (HWVP) process because of the potential influence of DF on secondary-waste recycle strategies (fluorine and chlorine) as well as its impact on off-gas emissions (iodine). This study directly establishes the concentrations of halides-in HWVP simulated reference glasses rather than relying on indirect off-gas data. For fluorine and chlorine, pyrohydrolysis coupled with halide (ion chromatographic) detection has proven to be a useful analytical approach suitable for glass matrices, sensitive enough for the range of halogens encountered, and compatible with remote process support applications. Results obtained from pyrohydrolytic analysis of pilot-scale ceramic melter (PSCM) -22 and -23 glasses indicate that the processing behavior of fluorine and chlorine is quite variable even under similar processing conditions. Specifically, PSCM-23 glass exhibited a ∼90% halogen (F and Cl) retention efficiency, while only 20% was incorporated in PSCM-22 glass. These two sets of very dissimilar test results clearly do not form a sufficient basis for establishing design DF values for fluorine and chlorine. Because the present data do not provide any new halogen volatility information, but instead reconfirm the validity of previously obtained offgas derived values, melter DF values of 4, 2, and 1 for fluorine, chlorine, and iodine, respectively, are recommended for adoption; these values were conservatively established by a team of responsible engineers at Westinghouse Hanford Company (WHC) and Pacific Northwest Laboratory (PNL) on the basis of average behavior for many comparable melter tests. In the absence of further HWVP process data, these average melter DFs are the best values currently available

  13. Development of an aerosol decontamination factor evaluation method using an aerosol spectrometer

    International Nuclear Information System (INIS)

    Kanai, Taizo; Furuya, Masahiro; Arai, Takahiro; Nishi, Yoshihisa

    2016-01-01

    Highlights: • Aerosol DF of each diameter is evaluable by using optical scattering method. • Outlet aerosol concentration shows exponential decay by the submergence. • This decay constant depends on the aerosol diameter. • Aerosol DF at water scrubber is described by simple equation. - Abstract: During a severe nuclear power plant accident, the release of fission products into containment and an increase in containment pressure are assumed to be possible. When the containment is damaged by excess pressure or temperature, radioactive materials are released. Pressure suppression pools, containment spray systems and a filtered containment venting system (FCVS) reduce containment pressure and reduce the radioactive release into the environment. These devices remove radioactive materials via various mechanisms. Pressure suppression pools remove radioactive materials by pool scrubbing. Spray systems remove radioactive materials by droplet−aerosol interaction. FCVS, which is installed in the exhaust system, comprises multi-scrubbers (venturi-scrubber, pool scrubbing, static mixer, metal−fiber filter and molecular sieve). For the particulate radioactive materials, its size affects the removal performance and a number of studies have been performed on the removal effect of radioactive materials. This study has developed a new means of evaluating aerosol removal efficiency. The aerosol number density of each effective diameter (light scattering equivalent diameter) is measured using an optical method, while the decontamination factor (DF) of each effective diameter is evaluated by the inlet outlet number density ratio. While the applicable scope is limited to several conditions (geometry of test section: inner diameter 500 mm × height 8.0 m, nozzle shape and air-water ambient pressure conditions), this study has developed a numerical model which defines aerosol DF as a function of aerosol diameter (d) and submergences (x).

  14. Development of an aerosol decontamination factor evaluation method using an aerosol spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Kanai, Taizo, E-mail: t-kanai@criepi.denken.or.jp; Furuya, Masahiro, E-mail: furuya@criepi.denken.or.jp; Arai, Takahiro, E-mail: t-arai@criepi.denken.or.jp; Nishi, Yoshihisa, E-mail: y-nishi@criepi.denken.or.jp

    2016-07-15

    Highlights: • Aerosol DF of each diameter is evaluable by using optical scattering method. • Outlet aerosol concentration shows exponential decay by the submergence. • This decay constant depends on the aerosol diameter. • Aerosol DF at water scrubber is described by simple equation. - Abstract: During a severe nuclear power plant accident, the release of fission products into containment and an increase in containment pressure are assumed to be possible. When the containment is damaged by excess pressure or temperature, radioactive materials are released. Pressure suppression pools, containment spray systems and a filtered containment venting system (FCVS) reduce containment pressure and reduce the radioactive release into the environment. These devices remove radioactive materials via various mechanisms. Pressure suppression pools remove radioactive materials by pool scrubbing. Spray systems remove radioactive materials by droplet−aerosol interaction. FCVS, which is installed in the exhaust system, comprises multi-scrubbers (venturi-scrubber, pool scrubbing, static mixer, metal−fiber filter and molecular sieve). For the particulate radioactive materials, its size affects the removal performance and a number of studies have been performed on the removal effect of radioactive materials. This study has developed a new means of evaluating aerosol removal efficiency. The aerosol number density of each effective diameter (light scattering equivalent diameter) is measured using an optical method, while the decontamination factor (DF) of each effective diameter is evaluated by the inlet outlet number density ratio. While the applicable scope is limited to several conditions (geometry of test section: inner diameter 500 mm × height 8.0 m, nozzle shape and air-water ambient pressure conditions), this study has developed a numerical model which defines aerosol DF as a function of aerosol diameter (d) and submergences (x).

  15. Surface decontamination

    International Nuclear Information System (INIS)

    Silva, S. da; Teixeira, M.V.

    1986-06-01

    The general methods of surface decontamination used in laboratory and others nuclear installations areas, as well as the procedures for handling radioactive materials and surfaces of work are presented. Some methods for decontamination of body external parts are mentioned. The medical supervision and assistance are required for internal or external contamination involving or not lesion in persons. From this medical radiation protection decontamination procedures are determined. (M.C.K.) [pt

  16. Full system decontamination (FSD) at NPP Stade prior to dismantling activities

    International Nuclear Information System (INIS)

    Christoph Stiepani; Karl Seidelmann

    2006-01-01

    Full text of publication follows: Introduction: Minimization of personnel dose rates and generation of material free for release is of the highest priority and requires Full System Decontamination (FSD) as a first and important measure when decommissioning Nuclear Power Plants. Framatome ANP has many years experience with Full System Decontaminations for operating nuclear power plants in general and for decommissioning in particular. The latest decommissioning project was the FSD at the PWR Stade which was permanently shut down in November 2003 after 31 years of operation. FSD was scheduled within a short period after shutdown and prior to decommissioning activities. Full System Decontamination at Stade: The PWR Stade is a 4 loop design. FSD included the entire primary circuit with RPV and the auxiliary systems (RHR, VCS and RWCU). The decontamination circuit had a total volume of ∼310 m 3 and an overall surface of ∼17000 m 2 . The Framatome ANP decontamination process HP/CORD R UV was selected for application. The decontamination was performed by using NPP systems in combination with the Framatome mobile decontamination equipment AMDA R (Automated Mobile Decontamination Appliance). A total of 4 decontamination cycles were performed and excellent results were obtained. The average decontamination factor (DF) was 160 for the steam generators with an outstanding ambient dose reduction factor (DRF) of 75. Conclusions: FSD at the PWR Stade has shown that the HP/CORD UV process yields excellent results in primary and auxiliary systems. The significant ambient dose reduction factor of 75 is remarkable. This very high DRF, no other decontamination application came even close, will result in excellent cost-benefit ratios for additional decommissioning activities at Stade. The applied HP/CORD UV process is not a specific decontamination process for decommissioning. Therefore the obtained decontamination and dose reduction factors demonstrate the advantage/potential for

  17. Factors to be considered in deciding whether to decontaminate for unrestricted release

    International Nuclear Information System (INIS)

    Loercher, G.; Chapuis, A.M.; Essmann, J.

    1984-01-01

    In the event of the total dismantling of a nuclear power station, a decision has to be reached as to whether large masses of material should and/or can be decontaminated to such a degree that they can subsequently be recycled or taken to a public refuse dump without being subject to radiological protection regulations. Technical, legal and economic aspects have to be taken into account in such a decision. The estimated costs for the final storage of radioactive waste range from DM 4 000 to DM 6 200 per Mg of net mass, depending on the type of final storage. In the Federal Republic of Germany, 50 Mg of steel scrap and 30 Mg of brass have already been decontaminated and melted down as part of the re-equipping of Wurgassen nuclear power station. (author)

  18. Lasers and high-energy light as a decontamination tool for nuclear applications

    International Nuclear Information System (INIS)

    Flesher, D.J.

    1993-12-01

    Light-aided decontamination (LAD) removal of paint and concrete layers is competitive with sand blasting rates. Remote operations, up to 137 m (450 ft), and lower waste volumes can provide cost, safety, and environmental advantages for nuclear facilities

  19. Heavy metals-bioremediation by highly radioresistant Deinococcus radiodurans biofilm prospective use in nuclear reactor decontamination

    International Nuclear Information System (INIS)

    Shukla, Sudhir K.; Subba Rao, T.

    2015-01-01

    Over the past few decades, rapid growth of chemical industries have enhanced the heavy metal contamination in water, thereby raising environmental concerns. In the nuclear power industry, decontamination procedure also generates radioactive heavy metal containing wastes. Radio-resistant Deinococcus radiodurans R1 is reported to be a potential candidate for the treatment of low active waste material. To use any bacterium for bioremediation purpose, knowledge about its biofilm production characteristics is a prerequisite. This is because biofilm-mediated bioremediation processes are more efficient as compared to processes mediated by their planktonic counterparts. However, so far there are no reports on the biofilm producing capability of D. radiodurans. We observed that tagging of D. radiodurans by a plasmid harbouring gfp and kan R conferred significant biofilm producing property to the bacterium. Chemical analysis of biofilm matrix components produced by D. radiodurans showed that the matrix consists primarily of proteins and carbohydrates with small amount of extracellular DNA (eDNA). Further, we studied the effect of Ca 2+ on D. radiodurans biofilm formation and it was observed that D. radiodurans biofilm formation was enhanced at higher concentrations of Ca 2+ . We investigated the capability of D. radiodurans biofilm to remove the heavy metals Co and Ni from synthetic waste streams. Results showed that Ca 2+ enhanced the bioremediation of both heavy metals (Co, Ni) by D. radiodurans biofilms in a highly significant manner. In the presence of 50 mM Ca 2+ 35% Co removal and 25% Ni removal was observed, when compared to biofilm grown in the absence of Ca 2+ , which showed mere 7% Co and 3% Ni removal, respectively. The results showed that the presence of Ca 2+ significantly enhanced exopolysaccharide and eDNA (both negatively charged) production in the biofilm matrix. This indicated adsorption could be the major mechanism behind enhanced biofilm mediated removal

  20. Recommendations for skin decontamination

    International Nuclear Information System (INIS)

    1989-01-01

    Further to the reecommendations for determining the surface contamination of the skin and estimating the radiation exposure of the skin after contamination (SAAS-Mitt--89-16), measures for skin decontamination are recommended. They are necessary if (1) after simple decontamination by means of water, soap and brush without damaging the skin the surface contamination limits are exceeded and the radiation exposure to be expected for the undamaged healthy skin is estimated as to high, and if (2) a wound is contaminated. To remove skin contaminations, in general universally applicable, non-aggressive decontamination means and methods are sufficient. In special cases, nuclide-specific decontamination is required taking into account the properties of the radioactive substance

  1. A study on environmental pollution caused by radioactive substances and its countermeasure techniques. Part 3. Development on decontamination techniques with high pressure cleaning method

    International Nuclear Information System (INIS)

    Narita, Yasunori; Nozaki, Atsuo; Kakuma, Takayuki; Shinohara, Naohide; Yoshino, Hiroshi

    2012-01-01

    A huge area of Fukushima was contaminated by the radiation released from the nuclear disaster. As a result, decontamination has become an urgent task in densely populated area and developments of an effective decontamination method are desired. So, we carried out the plan of the decontamination methods with a high pressure cleaner in present study. Surface with covered with concrete materials at horizontal plane was washed with high pressure cleaner, consequently, radioactivity was approximately 80% decreased. Further, the wash act with brushing are raised efficiency by 10%. So, the case of washing with surfactant shows no increase efficiency. (author)

  2. Decontamination sheet

    International Nuclear Information System (INIS)

    Hirose, Emiko; Kanesaki, Ken.

    1995-01-01

    The decontamination sheet of the present invention is formed by applying an adhesive on one surface of a polymer sheet and releasably appending a plurality of curing sheets. In addition, perforated lines are formed on the sheet, and a decontaminating agent is incorporated in the adhesive. This can reduce the number of curing operation steps when a plurality steps of operations for radiation decontamination equipments are performed, and further, the amount of wastes of the cured sheets, and operator's exposure are reduced, as well as an efficiency of the curing operation can be improved, and propagation of contamination can be prevented. (T.M.)

  3. Study on LOMI decontamination technology

    International Nuclear Information System (INIS)

    Huang Fuduan; Yu Degui; Lu Jingju; Xie Yinyan

    1993-10-01

    The results of decontamination technique of Low-Oxidation-State Metal-Ion (LOMI) reagents developed from 1986 to 1991 in the laboratory are introduced. The experiments included preparation of LOMI reagents, de-filming efficiency, corrosion behavior of typical alloys, decontamination factors of reagents for contaminated materials and components have proved that the NP/LOMI decontamination method and treatment technique of waste water are feasible and have some advantages. The preparation of LOMI reagent with low concentration of formic acid by reduced pressure distilling technique and the utilization ratio of vanadium reached to 95% by second electrolysis are the main contributions of the study to the decontamination technique

  4. Decontamination method

    International Nuclear Information System (INIS)

    Tsujimura, Hiroshi; Ono, Shigeki; Tada, Nobuo; Tamai, Yasumasa; Okada, Masaya; Kurihara, Masayuki; Onuki, Toyomitsu; Toyota, Seiichi

    1998-01-01

    Before contamination of materials to be decontaminated, a surface of a region where a strippable paint is to be coated is smoothed by an epoxy resin previously. Then, a waterproof sheet is extended to the material to be decontaminated, and the strippable paint is applied to the periphery or the entire surface of the sheet. In order to facilitate peeling, the strippable paint is not applied to a portion of the outer circumference of the sheet. Even if the contaminating circumstance is an air atmosphere or a liquid such as reactor water, since the sheet itself has waterproofness and the strippable paint excellent in gas and water tightness is applied to the periphery, contamination is eliminated. When decontaminating the material to be decontaminated having contaminated surfaces, if the sheet for the start of peeling is picked up and the sheet is peeled, the strippable paint at the periphery thereof can be peeled off together with the sheet. (N.H.)

  5. Decontamination method

    Energy Technology Data Exchange (ETDEWEB)

    Tsujimura, Hiroshi; Ono, Shigeki; Tada, Nobuo; Tamai, Yasumasa; Okada, Masaya; Kurihara, Masayuki [Hitachi Ltd., Tokyo (Japan); Onuki, Toyomitsu; Toyota, Seiichi

    1998-10-27

    Before contamination of materials to be decontaminated, a surface of a region where a strippable paint is to be coated is smoothed by an epoxy resin previously. Then, a waterproof sheet is extended to the material to be decontaminated, and the strippable paint is applied to the periphery or the entire surface of the sheet. In order to facilitate peeling, the strippable paint is not applied to a portion of the outer circumference of the sheet. Even if the contaminating circumstance is an air atmosphere or a liquid such as reactor water, since the sheet itself has waterproofness and the strippable paint excellent in gas and water tightness is applied to the periphery, contamination is eliminated. When decontaminating the material to be decontaminated having contaminated surfaces, if the sheet for the start of peeling is picked up and the sheet is peeled, the strippable paint at the periphery thereof can be peeled off together with the sheet. (N.H.)

  6. Skin decontamination

    International Nuclear Information System (INIS)

    Moehrle, G.

    1975-01-01

    A general survey of skin decontamination is given. The success of every decontamination treatments depends mainly on the speed, but also on the care, with which the action is taken. The best way to remove the skin contaminants is thorough washing under lukewarm running water with mild soap and a soft brush. This washing is to be repeated several times for a period of several minutes. If results are not satisfactory, light duty detergents and wetting agents available commercially may also be used. Some solutions which have proved useful are mentioned. The decontamination solutions are best used in the order given. When one has no satisfactory decontamination effect, the next one is to be used. If necessary, these agents must be used several times in the stated order as long as this does not involve too much strain for the skin. All the decontamination measures mentioned refer, of course, to intact healthy skin. After decontamination has been completed, the skin should be treated with a protective cream

  7. Effectiveness of deep cleaning followed by hydrogen peroxide decontamination during high Clostridium difficile infection incidence.

    Science.gov (United States)

    Best, E L; Parnell, P; Thirkell, G; Verity, P; Copland, M; Else, P; Denton, M; Hobson, R P; Wilcox, M H

    2014-05-01

    Clostridium difficile infection (CDI) remains an infection control challenge, especially when environmental spore contamination and suboptimal cleaning may increase transmission risk. To substantiate the long-term effectiveness throughout a stroke rehabilitation unit (SRU) of deep cleaning and hydrogen peroxide decontamination (HPD), following a high incidence of CDI. Extensive environmental sampling (342 sites on each occasion) for C. difficile using sponge wipes was performed: before and after deep cleaning with detergent/chlorine agent; immediately following HPD; and on two further occasions, 19 days and 20 weeks following HPD. C. difficile isolates underwent polymerase chain reaction ribotyping and multi-locus variable repeat analysis (MLVA). C. difficile was recovered from 10.8%, 6.1%, 0.9%, 0% and 3.5% of sites at baseline, following deep cleaning, immediately after HPD, and 19 days and 20 weeks after HPD, respectively. C. difficile ribotypes recovered after deep cleaning matched those from CDI cases in the SRU during the previous 10 months. Similarly, 10/12 of the positive sites identified at 20 weeks post-HPD harboured the same C. difficile ribotype (002) and MLVA pattern as the isolate from the first post-HPD CDI case. CDI incidence [number of cases on SRU per 10 months (January-October 2011)] declined from 20 before to seven after the intervention. HPD, after deep cleaning with a detergent/chlorine agent, was highly effective for removing environmental C. difficile contamination. Long-term follow-up demonstrated that a CDI symptomatic patient can rapidly recontaminate the immediate environment. Determining a role for HPD should include long-term cost-effectiveness evaluations. Copyright © 2014 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  8. Effect of Organic Solvents in Preparation of Silica-Based Chemical Gel Decontaminates for Decontamination of Nuclear Facilities

    International Nuclear Information System (INIS)

    Yoon, Suk Bon; Jung, Chong Hun; Kim, Chang Ki; Choi, Byung Seon; Lee, Kune Woo; Moon, Jei Kwon

    2011-01-01

    Decontamination of nuclear facilities is necessary to reduce the radiation field during normal operations and decommissioning of complex equipment such as stainless steel components, other iron-based steel and alloys, metal surfaces, structural materials and so on. Chemical decontamination technology in particular is a highly effective method to remove the radioactive contamination through a chemical dissolution or a redox reaction. However, this method has the serious drawback due to the generation of large amounts of the radioactive liquid wastes. Recently, a few literatures have been reported for the preparation of the chemical gel decontaminants to reduce the amount of the radioactive liquid wastes and to enhance the decontamination efficiency through increasing the contact time between the gels and the radioactive contaminants. In the preparation of the chemical gels, the control of the viscosity highly depends on the amount of a coviscosifier used among the components of the chemical gels consisted of a viscosifier, a coviscosifier, and a chemical decontaminant. In this works, a new effective method for the preparation of the chemical gel was investigated by introducing the organic solvents. The mixture solution of the coviscosifier and organic solvent was more effective in the control of the viscosity compared with that of the coviscosifier only in gels. Furthermore, the decontamination efficiency of the chemical gels measured by using the multi-channel analyzer (MCA) showed the high decontamination factor for Co-60 and Cs-137 contaminated on the surface of the stainless steel 304

  9. Decontamination of radioisotope production facility

    International Nuclear Information System (INIS)

    Daryoko, M.; Yatim, S.; Suseno, H.; Wiratmo, M.

    1998-01-01

    The strippable coating method use phosphoric glycerol and irradiated latex as supporting agents have been investigated. The investigation used some decontaminating agents: EDTA, citric acid, oxalic acid and potassium permanganate were combined with phosphoric glycerol supporting agent, then EDTA Na 2 , sodium citric, sodium oxalic and potassium permanganate were combined with irradiated latex supporting agent. The study was needed to obtain the representative operating data, will be implemented to decontamination the Hot Cell for radioisotope production. The experiment used 50x50x1 mm stainless steel samples and contaminated by Cs-137 about 1.1x10 -3 μCi/cm 2 . This samples according to inner cover of Hot Cell material, and Hot Cell activities. The decontamination factor results of the investigation were: phosphoric glycerol as supporting agent, about 20 (EDTA as decontaminating agent) to 47 (oxalic acid as decontaminating agent), and irradiated latex as supporting agent, about 11.5 (without decontamination agent) to 27 (KMnO 4 as decontaminating agent). All composition of the investigation have been obtained the good results, and can be implemented for decontamination of Hot Cell for radioisotope production. The irradiated latex could be recommended as supporting agent without decontaminating agent, because it is very easy to operate and very cheap cost. (author)

  10. Decontamination of nuclear facilities

    International Nuclear Information System (INIS)

    1982-01-01

    Thirty-seven papers were presented at this conference in five sessions. Topics covered include regulation, control and consequences of decontamination; decontamination of components and facilities; chemical and non-chemical methods of decontamination; and TMI decontamination experience

  11. W-12 valve pit decontamination demonstration

    International Nuclear Information System (INIS)

    Benson, C.E.; Parfitt, J.E.; Patton, B.D.

    1995-12-01

    Waste tank W-12 is a tank in the ORNL Low-Level Liquid Waste (LLLW) system that collected waste from Building 3525. Because of a leaking flange in the discharge line from W-12 to the evaporator service tank (W-22) and continual inleakage into the tank from an unknown source, W-12 was removed from service to comply with the Federal Facilities Agreement requirement. The initial response was to decontaminate the valve pit between tank W-12 and the evaporator service tank (W-22) to determine if personnel could enter the pit to attempt repair of the leaking flange. Preventing the spread of radioactive contamination from the pit to the environment and to other waste systems was of concern during the decontamination. The drain in the pit goes to the process waste system; therefore, if high-level liquid waste were generated during decontamination activities, it would have to be removed from the pit by means other than the available liquid waste connection. Remote decontamination of W-12 was conducted using the General Mills manipulator bridge and telescoping trolley and REMOTEC RM-10 manipulator. The initial objective of repairing the leaking flange was not conducted because of the repair uncertainty and the unknown tank inleakage. Rather, new piping was installed to empty the W-12 tank that would bypass the valve pit and eliminate the need to repair the flange. The radiological surveys indicated that a substantial decontamination factor was achieved

  12. Flowsheet development studies for the decontamination of high-activity-level water at Three Mile Island Unit 2

    International Nuclear Information System (INIS)

    Collins, E.D.; Bigelow, J.E.; Campbell, D.O.; King, L.J.; Knauer, J.B.

    1980-01-01

    Several chemical processing flowsheets were considered for the decontamination of high-activity-level water at the Three Mile Island (TMI) Unit 2. A zeolite ion exchange process was evaluated and recommended for absorption of the bulk of the highly radioactive cesium and strontium. Standard organic ion-exchange resins were selected to remove the remaining traces of radioactive nuclides (except tritium which cannot be removed by any practical process). Process conditions were evaluated using both synthetic, tracer-level solutions and samples of actual, high-activity level water from TMI Unit 2

  13. Decontamination of TRU glove boxes

    International Nuclear Information System (INIS)

    Crawford, J.H.

    1978-03-01

    Two glove boxes that had been used for work with transuranic nuclides (TRU) for about 12 years were decontaminated in a test program to collect data for developing a decontamination facility for large equipment highly contaminated with alpha emitters. A simple chemical technique consisting of a cycle of water flushes and alkaline permanganate and oxalic acid washes was used for both boxes. The test showed that glove boxes and similar equipment that are grossly contaminated with transuranic nuclides can be decontaminated to the current DIE nonretrievable disposal guide of <10 nCi TRU/g with a moderate amount of decontamination solution and manpower. Decontamination of the first box from an estimated 1.3 Ci to about 5 mCi (6 nCi/g) required 1.3 gallons of decontamination solution and 0.03 man-hour of work for each square foot of surface area. The second box was decontaminated from an estimated 3.4 Ci to about 2.8 mCi (4.2 nCi/g) using 0.9 gallon of decontamination solution and 0.02 man-hour for each square foot of surface area. Further reductions in contamination were achieved by repetitive decontamination cycles, but the effectiveness of the technique decreased sharply after the initial cycle

  14. Site decontamination

    International Nuclear Information System (INIS)

    Bicker, A.E.

    1981-01-01

    Among the several DOE sites that have been radiologically decontaminated under the auspices of the Nevada Operations Office are three whose physical characteristics are unique. These are the Tatum Dome Test Site (TDTS) near Hattiesburg, Mississippi; a location of mountainous terrain (Pahute Mesa) on the Nevada Test Site; and the GNOME site near Carlsbad, New Mexico. In each case the contamination, the terrain, and the climate conditions were different. This presentation includes a brief description of each site, the methods used to perform radiological surveys, the logistics required to support the decontamination (including health physics and sample analysis), and the specific techniques used to reduce or remove the contamination

  15. Pickering emulsions for skin decontamination.

    Science.gov (United States)

    Salerno, Alicia; Bolzinger, Marie-Alexandrine; Rolland, Pauline; Chevalier, Yves; Josse, Denis; Briançon, Stéphanie

    2016-08-01

    This study aimed at developing innovative systems for skin decontamination. Pickering emulsions, i.e. solid-stabilized emulsions, containing silica (S-PE) or Fuller's earth (FE-PE) were formulated. Their efficiency for skin decontamination was evaluated, in vitro, 45min after an exposure to VX, one of the most highly toxic chemical warfare agents. Pickering emulsions were compared to FE (FE-W) and silica (S-W) aqueous suspensions. PE containing an oil with a similar hydrophobicity to VX should promote its extraction. All the formulations reduced significantly the amount of VX quantified on and into the skin compared to the control. Wiping the skin surface with a pad already allowed removing more than half of VX. FE-W was the less efficient (85% of VX removed). The other formulations (FE-PE, S-PE and S-W) resulted in more than 90% of the quantity of VX removed. The charge of particles was the most influential factor. The low pH of formulations containing silica favored electrostatic interactions of VX with particles explaining the better elimination from the skin surface. Formulations containing FE had basic pH, and weak interactions with VX did not improve the skin decontamination. However, these low interactions between VX and FE promote the transfer of VX into the oil droplets in the FE-PE. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Toshiba's decontamination technologies for the decommissioning

    International Nuclear Information System (INIS)

    Inoue, Yuki; Yaita, Yumi; Sakai, Hitoshi

    2011-01-01

    For the decommissioning, two types of decontamination process are necessary, 1) system decontamination before dismantling and 2) decontamination of dismantling waste. Toshiba has been developing the decontamination technologies for the both purposes from the viewpoint of minimizing the secondary waste. For the system decontamination before dismantling, chemical decontamination process, such as T-OZON, can be applicable for stainless steel or carbon steel piping. For the decontamination of dismantling waste, several types of process have been developed to apply variety of shapes and materials. For the simple shape materials, physical decontamination process, such as blast decontamination, is effective. We have developed new blast decontamination process with highly durable zirconia particle. It can be used repeatedly and secondary waste can be reduced compared with conventional blast particle. For the complex shape materials, chemical decontamination process can be applied that formic acid decontamination process for carbon steel and electrolytic reduction decontamination process with organic acid for stainless steel. These chemicals can be decomposed to carbon dioxide and water and amount of secondary waste can be small. (author)

  17. Ultra-high tritium decontamination of simulated fusion fuel exhaust using a 2-stage palladium membrane reactor

    International Nuclear Information System (INIS)

    Birdsell, S.A.; Willms, R.S.; Wilhelm, R.C.

    1996-01-01

    A 2-stage cold (non-tritium) PMR system was tested with the ITER mix in61 days of continuous operation. No decrease in performance was observed over the duration of the test. Decontamination factor (DF) was found to increase with decreasing inlet rate. Decontamination factors in excess of 1.4 x 10 5 were obtained, but the exact value of the highest DF could not be determined because of analysis limitations. Results of the 61-day test were used to design a 2-stage PMR system for use in tritium testing. The PMR system was scaled up by a factor of 6 and built into a glovebox in the Tritium Systems Test Assembly (TSTA) of the Los Alamos National Laboratory. This system is approximately 1/5th of the expected full ITER scale. The ITER mix was injected into the PMR system for 31 hours, during which 4.5 g of tritium were processed. The 1st stage had DF = 200 and the 2nd stage had DF = 2.9 x 10 6 . The overall DF = 5.8 x 10 8 , which is greater than ITER requirements

  18. Optimization of Thermochemical, Kinetic, and Electrochemical Factors Governing Partitioning of Radionuclides During Melt Decontamination of Radioactively Contaminated Stainless Steel; TOPICAL

    International Nuclear Information System (INIS)

    VAN DEN AVYLE, JAMES A.; MALGAARD, DAVID; MOLECKE, MARTIN; PAL, UDAY B.; WILLIAMSON, RODNEY L.; ZHIDKOV, VASILY V.

    1999-01-01

    The Research Objectives of this project are to characterize and optimize the use of molten slags to melt decontaminate radioactive stainless steel scrap metal. The major focus is on optimizing the electroslag remelting (ESR) process, a widely used industrial process for stainless steels and other alloys, which can produce high quality ingots directly suitable for forging, rolling, and parts fabrication. It is our goal to have a melting process ready for a DOE D and D demonstration at the end of the third year of EMSP sponsorship, and this technology could be applied to effective stainless steel scrap recycle for internal DOE applications. It also has potential international applications. The technical approach has several elements: (1) characterize the thermodynamics and kinetics of slag/metal/contaminate reactions by models and experiments, (2) determine the capacity of slags for radioactive containment, (3) characterize the minimum levels of residual slags and contaminates in processed metal, and (4) create an experimental and model-based database on achievable levels of decontamination to support recycle applications. Much of the experimental work on this project is necessarily focused on reactions of slags with surrogate compounds which behave similar to radioactive transuranic and actinide species. This work is being conducted at three locations. At Boston University, Prof. Uday Pal's group conducts fundamental studies on electrochemical and thermochemical reactions among slags, metal, and surrogate contaminate compounds. The purpose of this work is to develop a detailed understanding of reactions in slags through small laboratory scale experiments and modeling. At Sandia, this fundamental information is applied to the design of electroslag melting experiments with surrogates to produce and characterize metal ingots. In addition, ESR furnace conditions are characterized, and both thermodynamic and ESR process models are utilized to optimize the process. To

  19. Decontamination of CAGR gas circulator components

    International Nuclear Information System (INIS)

    Rogers, L.N.; Hooper, A.J.

    1985-01-01

    This paper describes the development and full-scale trial of two methods for removal of radioactive contamination on the surfaces of CAGR gas circulator components. The two methods described are a particle impact cleaning (PIC) decontamination technique and an electrochemical technique, 'electro-swabbing', which is based on the principle of decontamination by electro-polishing. In developing these techniques it was necessary to take account of the physical and chemical nature of the surface deposits on the gas circulator components; these were shown to consist of magnetite-type oxide and carbonaceous material. In order to follow the progress of the decontamination it was also necessary to develop a surface sampling technique which was effective and precise under these conditions; an electrochemical technique, employing similar principles to the electro-swabbing process, was developed for this purpose. The full-scale trial of the PIC decontamination technique was carried out on an inlet guide vane (IGV) assembly, this having been identified as the component from the gas circulator which contributes most to the radiation dose accumulated during routine circulator maintenance. The technique was shown to be practically viable and some 99% of the radioactive contamination was readily removed from the treated surfaces with only negligible surface damage being caused. The full-scale trial of the electro-swabbing decontamination technique was carried out on a gas circulator impeller. High decontamination factors were again achieved with ≥ 99% of the radioactive contamination being removed from the treated surfaces. The technique has practical limitations in terms of handling and treatment of waste-arisings. However, the use of specially-designed swabbing electrodes may allow the treatment of constricted geometries inaccessible to techniques such as PIC. The technique is also highly suitable for the treatment of soft-finish materials and of components fabricated from a

  20. DEMONSTRATION AND EVALUATION OF POTENTIAL HIGH LEVEL WASTE MELTER DECONTAMINATION TECHNOLOGIES FOR SAVANNAH RIVER SITE

    International Nuclear Information System (INIS)

    Weger, Hans; Kodanda, Raja Tilek Meruva; Mazumdar, Anindra; Srivastava, Rajiv Ph.D.; Ebadian, M.A. Ph.D.

    2003-01-01

    Four hand-held tools were tested for failed high-level waste melter decontamination and decommissioning (D and D). The forces felt by the tools during operation were measured using a tri-axial accelerometer since they will be operated by a remote manipulator. The efficiency of the tools was also recorded. Melter D and D consists of three parts: (1) glass fracturing: removing from the furnace the melted glass that can not be poured out through normal means, (2) glass cleaning: removing the thin layer of glass that has formed over the surface of the refractory material, and (3) K-3 refractory breakup: removing the K-3 refractory material. Surrogate glass, from a formula provided by the Savannah River Site, was melted in a furnace and poured into steel containers. K-3 refractory material, the same material used in the Defense Waste Processing Facility, was utilized for the demonstrations. Four K-3 blocks were heated at 1150 C for two weeks with a glass layer on top to simulate the hardened glass layer on the refractory surface in the melter. Tools chosen for the demonstrations were commonly used D and D tools, which have not been tested specifically for the different aspects of melter D and D. A jackhammer and a needle gun were tested for glass fracturing; a needle gun and a rotary grinder with a diamond face wheel (diamond grinder) were tested for glass cleaning; and a jackhammer, diamond grinder, and a circular saw with a diamond blade were tested for refractory breakup. The needle gun was not capable of removing or fracturing the surrogate glass. The diamond grinder only had a removal rate of 3.0 x 10-4 kg/s for K-3 refractory breakup and needed to be held firmly against the material. However, the diamond grinder was effective for glass cleaning, with a removal rate of 3.9 cm2/s. The jackhammer was successful in fracturing glass and breaking up the K-3 refractory block. The jackhammer had a glass-fracturing rate of 0.40 kg/s. The jackhammer split the K-3 refractory

  1. Investigation on safety of gel decontamination technology

    International Nuclear Information System (INIS)

    Liu Zhihui; Song Fengli; Wang Yongxian; Zhang Taoge

    2014-01-01

    Gel decontamination technology is an advanced decontamination process of metal contaminated by radionuclide. It has the advantages such as simple operation process, high decontaminating factor, etc. But the disadvantages are that it has high spraying pressure and is strongly corrosive, which has safety risk to the operator and equipment. The effect of such factors as spraying pressure on operators was analyzed based on process feature, and it is proposed that it be worthwhile to make further study on the corrosion of gels to spraying equipment, taking into account corrosion feature of gels to stainless steel. Meanwhile, the safety issue was demonstrated on collecting and handling wastes from gel decontamination process. And then, protective measures, study methods, and solutions are put forward. The results show that protection should be strengthened during spraying to reduce the effect of splashing and fogging on workers; the equipment should be cleaned in time to reduce the effect of corrosion, and reducers should be added into waste liquid to eliminate the effect of residual detergent. (authors)

  2. Dilute chemical decontamination program review

    International Nuclear Information System (INIS)

    Anstine, L.D.; Blomgren, J.C.; Pettit, P.J.

    1980-01-01

    The objective of the Dilute Chemical Decontamination Program is to develop and evaluate a process which utilizes reagents in dilute concentrations for the decontamination of BWR primary systems and for the maintenance of dose rates on the out-of-core surfaces at acceptable levels. A discussion is presented of the process concept, solvent development, advantages and disadvantages of reagent systems, and VNC loop tests. Based on the work completed to date it is concluded that (1) rapid decontamination of BWRs using dilute reagents is feasible; (2) reasonable reagent conditions for rapid chemical decontamination are: 0.01M oxalic acid + 0.005M citric acid, pH3.0, 90/degree/C, 0.5 to 1.0 ppm dissolved oxygen; (3) control of dissolved oxygen concentration is important, since high levels suppress the rate of decontamination and low levels allow precipitation of ferrous oxalate. 4 refs

  3. The study of road surface micro-texture's effects for the pavement's decontamination by high pressure water washing

    International Nuclear Information System (INIS)

    Kobayashi, Masatoshi; Shimizu, Tadaaki; Hirayama, Takahiro

    2014-01-01

    In the result of “decontamination technical demonstration project” by Ministry of the Environment, it has became clear that the effect variation is larger in high pressure water washing method, compared with others in road surface decontamination technology. In this study, we have hypothesized the fact at the difference of micro-texture of the road surface, by carrying out high pressure water washing method in different kinds of road surfaces and verified the relation between washing efficiency and micro-texture road surface. Positive correlation has admitted between the washing number of times and radiation reduction rate and the trend of primary regression equation (i.e. radiation reduction rate per washing time) is indicating that decreasing tendency of radiation carried by the increasing of micro-texture of the road surface. Here, we proposed the method to estimated essential washing number of times to achieve the targeted radiation reduction rate from the relation of that trend and micro-texture of the road surface. (author)

  4. Assessment, evaluation, and testing of technologies for environmental restoration, decontamination, and decommissioning and high level waste management. Progress report

    International Nuclear Information System (INIS)

    Uzochukwu, G.A.

    1997-01-01

    Nuclear and commercial non-nuclear technologies that have the potential of meeting the environmental restoration, decontamination and decommissioning, and high-level waste management objectives are being assessed and evaluated. A detailed comparison of innovative technologies available will be performed to determine the safest and most economical technology for meeting these objectives. Information derived from this effort will be matched with the multi-objectives of the environmental restoration, decontamination and decommissioning, and high-level waste management effort to ensure that the best, most economical, and the safest technologies are used in decision making at USDOE-SRS. Technology-related variables will be developed and the resulting data formatted and computerized for multimedia systems. The multimedia system will be made available to technology developers and evaluators to ensure that the best, most economical, and the safest technologies are used in decision making at USDOE-SRS. Technology-related variables will be developed and the resulting data formatted and computerized for multimedia systems. The multimedia system will be made available to technology developers and evaluators to ensure that the safest and most economical technologies are developed for use at SRS and other DOE sites

  5. Assessment, evaluation, and testing of technologies for environmental restoration, decontamination, and decommissioning and high level waste management. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Uzochukwu, G.A.

    1997-12-31

    Nuclear and commercial non-nuclear technologies that have the potential of meeting the environmental restoration, decontamination and decommissioning, and high-level waste management objectives are being assessed and evaluated. A detailed comparison of innovative technologies available will be performed to determine the safest and most economical technology for meeting these objectives. Information derived from this effort will be matched with the multi-objectives of the environmental restoration, decontamination and decommissioning, and high-level waste management effort to ensure that the best, most economical, and the safest technologies are used in decision making at USDOE-SRS. Technology-related variables will be developed and the resulting data formatted and computerized for multimedia systems. The multimedia system will be made available to technology developers and evaluators to ensure that the best, most economical, and the safest technologies are used in decision making at USDOE-SRS. Technology-related variables will be developed and the resulting data formatted and computerized for multimedia systems. The multimedia system will be made available to technology developers and evaluators to ensure that the safest and most economical technologies are developed for use at SRS and other DOE sites.

  6. Nuclear decontamination

    International Nuclear Information System (INIS)

    LeSurf, J.E.

    1981-01-01

    Decontamination may be accomplished by chemical, electrical, or mechanical means. Recently there have been significant developments in all three categories as well as an increased tendency to combine techniques, either simultaneously (e.g. by adding chemicals to water jets) or sequentially (e.g. by using a mechanical method to remove loose contamination, followed by a chemical method for more tightly bound activity). Some developments in the different techniques are discussed, together with typical applications of each. (author)

  7. Decontaminating method

    International Nuclear Information System (INIS)

    Furukawa, Toshiharu; Shibuya, Kiichiro.

    1985-01-01

    Purpose: To provide a method of eliminating radioactive contaminations capable of ease treatment for decontaminated liquid wastes and grinding materials. Method: Those organic grinding materials such as fine wall nuts shell pieces cause no secondary contaminations since they are softer as compared with inorganic grinding materials, less pulverizable upon collision against the surface to be treated, being capable of reusing and producing no fine scattering powder. In addition, they can be treated by burning. The organic grinding material and water are sprayed by a nozzle to the surface to be treated, and decontaminated liquid wastes are separated into solid components mainly composed of organic grinding materials and liquid components mainly composed of water by filtering. The thus separated solid components are recovered in a storage tank for reuse as the grinding material and, after repeating use, subjected to burning treatment. While on the other hand, water is recovered into a storage tank and, after repeating use, purified by passing through an ion exchange resin-packed column and decontaminated to discharge. (Horiuchi, T.)

  8. Decontamination processes for waste glass canisters

    International Nuclear Information System (INIS)

    Rankin, W.N.

    1981-06-01

    The process which will be used to decontaminate waste glass canisters at the Savannah River Plant consists of: decontamination (slurry blasting); rinse (high-pressure water); and spot decontamination (high-pressure water plus slurry). No additional waste will be produced by this process because glass frit used in decontamination will be mixed with the radioactive waste and fed into the glass melter. Decontamination of waste glass canisters with chemical and abrasive blasting techniques was investigated. The ability of a chemical technique with HNO 3 -HF and H 2 C 2 O 4 to remove baked-on contamination was demonstrated. A correlation between oxide removal and decontamination was observed. Oxide removal and, thus, decontamination by abrasive blasting techniques with glass frit as the abrasive was proposed and demonstrated

  9. Decontamination processes for waste glass canisters

    International Nuclear Information System (INIS)

    Rankin, W.N.

    1981-01-01

    The process which will be used to decontaminate waste glass canisters at the Savannah River Plant consists of: decontamination (slurry blasting); rinse (high-pressure water); and spot decontamination (high-pressure water plus slurry). No additional waste will be produced by this process because glass frit used in decontamination will be mixed with the radioactive waste and fed into the glass melter. Decontamination of waste glass canisters with chemical and abrasive blasting techniques was investigated. The ability of a chemical technique with HNO 3 -HF and H 2 C 2 O 4 to remove baked-on contamination was demonstrated. A correlation between oxide removal and decontamination was observed. Oxide removal and, thus, decontamination by abrasive blasting techniques with glass frit as the abrasive was proposed and demonstrated

  10. Development and assessment of two decontamination processes: closed electropolishing system for decontamination of underwater surfaces -vibratory decontamination with abrasives

    International Nuclear Information System (INIS)

    Benavides, E.; Fajardo, M.

    1992-01-01

    Two decontamination processes have been developed to decontaminate the stainless steel components of nuclear power plants. The first process uses an underwater closed electropolishing system for the decontamination of large stainless steel surfaces in flooded systems without loss of electrolyte. Large underwater contaminated areas can be treated with an electropolishing head covering an area of 2 m 2 in one step. The decontamination factors achieved with this technique range between 100 and 1000. The second process consists in the decontamination of nuclear components using vibratory equipment with self-cleaning abrasives generating a minimum quantity of waste. This technique may reach contamination factors similar to those obtained with other abrasive methods (brush abrasion, abrasive blasting, etc...). The obtained decontamination factors range between 5 and 50. Only a small quantity of waste is generated, which is treated and reduced in volume by filtration and evaporation

  11. Evaluation of a decontamination model

    International Nuclear Information System (INIS)

    Rippin, D.W.T.; Hanulik, J.; Schenker, E.; Ullrich, G.

    1981-02-01

    In the scale-up of a laboratory decontamination process difficulties arise due to the limited understanding of the mechanisms controlling the process. This paper contains some initial proposals which may contribute to the quantitative understanding of the chemical and physical factors which influence decontamination operations. General features required in a mathematical model to describe a fluid-solid reaction are discussed, and initial work is presented with a simple model which has had some success in describing the observed laboratory behaviour. (Auth.)

  12. Decontamination Data - Blister Agents

    Data.gov (United States)

    U.S. Environmental Protection Agency — Decontamination efficacy data for blister agents on various building materials using various decontamination solutions. This dataset is associated with the following...

  13. Radioactivity decontamination efficiency of ceramic filter in an incineration volume reduction system of radioactive waste

    International Nuclear Information System (INIS)

    Kanbe, Hiromi; Mayuzumi, Masami; Yoshiki, Sinya; Sema, Toru; Koyama, Hiroaki; Ono, Tetsuo; Nagae, Madoka; Takaoku, Yoshinobu; Hozumi, Masahiro.

    1987-01-01

    The small pilot facility of a cyclone type suspension incineration system of radioactive waste was set up in order to evaluate the decontamination efficiency of a high efficiency ceramic filter. The evaluation was made by use of 54 Mn, 59 Fe, 60 Co, 65 Zn and 137 Cs. 1. The decontamination factor by one line of ceramic filter for every species were over 10 5 . 2. The decontamination factor increased by one oder when water vapor exists in off-gas. The same tendency was also observed when iron dioxide existed at the incineration of cation exchange resin. (author)

  14. Decontamination for free release

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, K A; Elder, G R [Bradtec Ltd., Bristol (United Kingdom)

    1997-02-01

    Many countries are seeking to treat radioactive waste in ways which meet the local regulatory requirements, but yet are cost effective when all contributing factors are assessed. In some countries there are increasing amounts of waste, arising from nuclear plant decommissioning, which are categorized as low level waste: however with suitable treatment a large part of such wastes might become beyond regulatory control and be able to be released as non-radioactive. The benefits and disadvantages of additional treatment before disposal need to be considered. Several processes falling within the overall description of decontamination for free release have been developed and applied, and these are outlined. In one instance the process seeks to take advantage of techniques and equipment used for decontaminating water reactor circuits intermittently through reactor life. (author). 9 refs, 1 fig., 3 tabs.

  15. Analytical methodology for the study of decontamination factors in mixer-settlers

    International Nuclear Information System (INIS)

    Alzabet, Horacio; Crubellati, Ricardo; Di Santo, Norberto; Eppis, Maria; Gonzalez, Guillermo; Bof, Elba; Devida, Claudio

    1987-01-01

    Due to the complexity of the samples, the choice of the analytical methodology to be applied at a radiochemical laboratory, for the evaluation of different separation steps if of a great importance. It is necessary to know the performance of mixer-settlers in two extreme situations: efficiency limit determined by fluid dynamic factors and separation factor determined by physicochemical variables. The element used to determine the efficiency limit was magnesium, due to its low distribution coefficient in tri-n-butyl phosphate (TBP). Zirconium, being one of the principal fission product, is partially extracted and was used to study the influence of chemical conditions. Atomic absorption spectrometry was selected for the determination of micro quantities of magnesium, and complexometry for macro quantities of this element. It was necessary to separate uranium using extraction chromatography with Kel F-TBP columns. Concentration range was 0.1 - 1 mg/L and 7 - 70 g/L respectively. Zirconium was determined by spectrophotometry with xylenol orange. For organic samples, it was necessary to reextract the analyte with fluoride, to evaporate with sulfuric acid and to complex the excess of fluoride with aluminum. Uranium determinations, required for mass balance, were carried out by spectrophotometry and potentiometry depending upon concentration. Because of the presence of zirconium, two methods were developed for uranium determination using liquid-liquid extraction in the presence of complexing agents. In one case, TBP was used as extractant, dibenzoylmethane as chromogenic reagent and EDTA as complexing agent. For very low quantities of uranium, tri-octyl phosphine oxide (TOPO) was the extractant, 2-(2-thiazolylazo)-5-diethylaminophenol (TAAP) the chromogenic reagent, and (1-2-cyclohexylenedinitrilo) tetraacetic acid (CDTA) the complexing agent. (Author)

  16. Non-destructive decontamination of building materials

    Science.gov (United States)

    Holecek, Josef; Otahal, Petr

    2015-11-01

    For nondestructive radiation decontamination of surfaces it is necessary to use varnishes, such as ARGONNE, DG1101, DG1108, etc. This text evaluates the use of manufactured strippable coatings for radiation decontamination. To evaluate decontamination capability of such coatings the following varnishes were selected and subsequently used: AZ 1-700 and AXAL 1807S. The varnishes were tested on different building materials surfaces contaminated by short-term radioisotopes of Na-24 or La-140, in water soluble or water insoluble forms. Decontamination quality was assessed by the decontamination efficiency value, defined as the proportion of removed activity to the applied activity. It was found that decontamination efficiency of both used varnishes depends not only on the form of contaminant, but in the case of application of AXAL 1807S varnish it also depends on the method of its application on the contaminated surface. The values of the decontamination efficiency for AZ1-700 varnish range from 46% for decontamination of a soluble form of the radioisotope from concrete surface to 98% for the decontamination of a soluble form of the radioisotope from ceramic tile surface. The decontamination efficiency values determined for AXAL 1807S varnish range from 48% for decontamination of a soluble form of the radioisotope from concrete surface to 96% for decontamination of an insoluble form of the radioisotope from ceramic tile surface. Comparing these values to the values given for the decontaminating varnishes we can conclude that AXAL 1807S varnish is possible to use on all materials, except highly porous materials, such as plasterboard or breeze blocks, or plastic materials. AZ 1-700 varnish can be used for all dry materials except plasterboard.

  17. Local strategies for decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Hubert, P [Institut de Protection et de Surete Nucleaire, Fontenay-aux-Roses cedex (France); Ramzaev, V [Branch of Institute of Radiation Hygiene, Novozybkov, Bryansk region (Russian Federation); Antsypov, G [Chernnobyl State Committee of the Republic of Belarus, Minsk (Belarus); Sobotovich, E [Institute of Geochemistry, Mineralogy and Ore formation, Kiev (Ukraine); Anisimova, L [EMERCOM, Moscow (Russian Federation)

    1996-07-01

    The efficiencies of a great number of techniques for decontamination or dose reduction in contaminated areas have been investigated by several teams of E.C. and CIS scientists (ECP4 project). Modelling, laboratory and field experiments, t and return from experience allowed to assess radiological efficiencies (e.g. 'decontamination factor') and requirements for the operation of numerous practical solutions. Then, those data were supplemented with data on cost and waste generation in order to elaborate all the information for the optimization of decontamination strategies. Results will be presented for about 70 techniques. However, a technique cannot be compared to another from a generic point of view. Rather it is designed for a specific target and the best technology depends on the objectives. It has been decided to implement decision analyses on case studies, and the local conditions and objectives have been investigated. Individual doses ranged from 1 to 5 mSv, with contrasted contributions of internal and external doses. The desire to restore a normal activity in a partially depopulated settlement, and concerns about the recent increase in internal doses were typical incentives for action. The decision aiding analysis illustrated that actions can be usually recommended. Results are outlined here.

  18. Local strategies for decontamination

    International Nuclear Information System (INIS)

    Hubert, P.; Ramzaev, V.; Antsypov, G.; Sobotovich, E.; Anisimova, L.

    1996-01-01

    The efficiencies of a great number of techniques for decontamination or dose reduction in contaminated areas have been investigated by several teams of E.C. and CIS scientists (ECP4 project). Modelling, laboratory and field experiments, t and return from experience allowed to assess radiological efficiencies (e.g. 'decontamination factor') and requirements for the operation of numerous practical solutions. Then, those data were supplemented with data on cost and waste generation in order to elaborate all the information for the optimization of decontamination strategies. Results will be presented for about 70 techniques. However, a technique cannot be compared to another from a generic point of view. Rather it is designed for a specific target and the best technology depends on the objectives. It has been decided to implement decision analyses on case studies, and the local conditions and objectives have been investigated. Individual doses ranged from 1 to 5 mSv, with contrasted contributions of internal and external doses. The desire to restore a normal activity in a partially depopulated settlement, and concerns about the recent increase in internal doses were typical incentives for action. The decision aiding analysis illustrated that actions can be usually recommended. Results are outlined here

  19. Chemical Gel for Surface Decontamination

    International Nuclear Information System (INIS)

    Jung, Chong Hun; Moon, J. K.; Won, H. J.; Lee, K. W.; Kim, C. K.

    2010-01-01

    Many chemical decontamination processes operate by immersing components in aggressive chemical solutions. In these applications chemical decontamination technique produce large amounts of radioactive liquid waste. Therefore it is necessary to develop processes using chemical gels instead of chemical solutions, to avoid the well-known disadvantages of chemical decontamination techniques while retaining their high efficiency. Chemical gels decontamination process consists of applying the gel by spraying it onto the surface of large area components (floors, walls, etc) to be decontaminated. The gel adheres to any vertical or complex surface due to their thixotropic properties and operates by dissolving the radioactive deposit, along with a thin layer of the gel support, so that the radioactivity trapped at the surface can be removed. Important aspects of the gels are that small quantities can be used and they show thixitropic properties : liquid during spraying, and solid when stationary, allowing for strong adherence to surfaces. This work investigates the decontamination behaviors of organic-based chemical gel for SS 304 metallic surfaces contaminated with radioactive materials

  20. Salt decontamination demonstration test results

    International Nuclear Information System (INIS)

    Snell, E.B.; Heng, C.J.

    1983-06-01

    The Salt Decontamination Demonstration confirmed that the precipitation process could be used for large-scale decontamination of radioactive waste sale solution. Although a number of refinements are necessary to safely process the long-term requirement of 5 million gallons of waste salt solution per year, there were no observations to suggest that any fundamentals of the process require re-evaluation. Major accomplishments were: (1) 518,000 gallons of decontaminated filtrate were produced from 427,000 gallons of waste salt solution from tank 24H. The demonstration goal was to produce a minimum of 200,000 gallons of decontaminated salt solution; (2) cesium activity in the filtrate was reduced by a factor of 43,000 below the cesium activity in the tank 24 solution. This decontamination factor (DF) exceeded the demonstration goal of a DF greater than 10,000; (3) average strontium-90 activity in the filtrate was reduced by a factor of 26 to less than 10 3 d/m/ml versus a goal of less than 10 4 d/m/ml; and (4) the concentrated precipitate was washed to a final sodium ion concentration of 0.15 M, well below the 0.225 M upper limit for DWPF feed. These accomplishments were achieved on schedule and without incident. Total radiation exposure to personnel was less than 350 mrem and resulted primarily from sampling precipitate slurry inside tank 48. 3 references, 6 figures, 2 tables

  1. Microbiological decontamination of natural honey by irradiation

    Science.gov (United States)

    Migdał, W.; Owczarczyk, H. B.; K ȩdzia, B.; Hołderna-K ȩdzia, E.; Madajczyk, D.

    2000-03-01

    Degree of microbiological decontamination, organoleptic and physico-chemical properties of natural honeys were investigated after radiation treatment. Seven kinds of honeys were irradiated with the beams of 10 MeV electrons from a 10 kW linear accelerator "Elektronika 10-10" at the dose 10 kGy. It was shown, that after irradiation, the total count of aerobic and anaerobic bacteria and moulds decrease by 99%. The antibiotic value in investigated honeys increased in turn from 1.67 to 2.67 after irradiation. Such factors and parameters of investigated honeys as their consistency, content of water and saccharose, acidity, the diastase and 5-HMF values were not changed significantly after irradiation. Decontamination by irradiation is a process which allows us to obtain high microbiological purity of honeys. It is especially needed, when honeys are used in surgical treatment of injuries and in nutrition of babies with food deficiency.

  2. Microbiological decontamination of natural honey by irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Migdal, W.; Owczarczyk, H.B.; Kedzia, B.; Holderna-Kedzia, E.; Madajczyk, D

    2000-03-01

    Degree of microbiological decontamination, organoleptic and physico-chemical properties of natural honeys were investigated after radiation treatment. Seven kinds of honeys were irradiated with the beams of 10 MeV electrons from a 10 kW linear accelerator ''Elektronika 10-10'' at the dose 10 kGy. It was shown, that after irradiation, the total count of aerobic and anaerobic bacteria and moulds decrease by 99%. The antibiotic value in investigated honeys increased in turn from 1.67 to 2.67 after irradiation. Such factors and parameters of investigated honeys as their consistency, content of water and saccharose, acidity, the diastase and 5-HMF values were not changed significantly after irradiation. Decontamination by irradiation is a process which allows us to obtain high microbiological purity of honeys. It is especially needed, when honeys are used in surgical treatment of injuries and in nutrition of babies with food deficiency.

  3. Microbiological decontamination of natural honey by irradiation

    International Nuclear Information System (INIS)

    Migdal, W.; Owczarczyk, H.B.; Kedzia, B.; Holderna-Kedzia, E.; Madajczyk, D.

    2000-01-01

    Degree of microbiological decontamination, organoleptic and physico-chemical properties of natural honeys were investigated after radiation treatment. Seven kinds of honeys were irradiated with the beams of 10 MeV electrons from a 10 kW linear accelerator ''Elektronika 10-10'' at the dose 10 kGy. It was shown, that after irradiation, the total count of aerobic and anaerobic bacteria and moulds decrease by 99%. The antibiotic value in investigated honeys increased in turn from 1.67 to 2.67 after irradiation. Such factors and parameters of investigated honeys as their consistency, content of water and saccharose, acidity, the diastase and 5-HMF values were not changed significantly after irradiation. Decontamination by irradiation is a process which allows us to obtain high microbiological purity of honeys. It is especially needed, when honeys are used in surgical treatment of injuries and in nutrition of babies with food deficiency

  4. Chemical decontamination and melt densification of chop-leach fuel hulls

    International Nuclear Information System (INIS)

    Dillon, R.L.; Griggs, B.; Kemper, R.S.; Nelson, R.G.

    1976-01-01

    This paper reports on decontamination and densification studies of chop-leach fuel hull residues designed to minimize the transuranic element (TRU) contaminated waste stream. Decontamination requirements have been established from studies of TRU element distribution in the fuel hull residues. Effective surface decontamination of Zircaloy requires removal of zirconium oxide corrosion products. Good decontamination factors have been achieved with aqueous solutions following high temperature HF conditioning of oxide films. Molten fluoride salt mixtures are effective decontaminants, but pose problems in metal loss and salt dragout. Molten metal decontamination methods are highly preliminary, but may be required to reduce TRU originating from tramp uranium in Zircaloy. Low melting (1300 0 C) alloy of Zircaloy, stainless steel, and Inconel have been prepared in induction heated graphite crucibles. High quality ingots of Zircaloy-2 have been prepared directly from short sections of descaled fuel clad tubing using the Inductoslag process. This material is readily capable of refabrication. Inductoslag melts have also been prepared from heavily oxidized Zircaloy tubing demonstrating melt densification without prior decontamination is technically feasible. Hydrogen absorption kinetics have been demonstrated with cast Zircaloy-2 and cast Zircaloy-stainless steel-Inconel alloys. Metallic fuel hull residues have been proposed as a storage medium for tritium released from fuel during reprocessing. (author)

  5. Alpha Decontamination and Disassembly Pilot Facility. Final report

    International Nuclear Information System (INIS)

    Daugherty, B.A.; Clark, H.E.

    1985-04-01

    The Alpha Decontamination and Disassembly (AD and D) Pilot Facility was built to develop and demonstrate a reference process for the decontamination and size reduction of noncombustible transuranic (TRU) waste. The goals of the reference process were to remove >99% of the surface contamination to the high-level waste tanks, and to achieve volume reduction factors greater than 15:1. Preliminary bench-scale decontamination work was accomplished at Savannah River Laboratory (SRL), establishing a reference decontamination process. Initially, the pilot facility did not achieve the decontamination goals. As the program continued, and modifications to the process were made, coupon analysis idicated that 99% of the surface contamination was removed to the high-level drain system. Prior to the AD and D Pilot Facility, no size reduction work had been done at SRL. Several other Department of Energy (DOE) facilities were experimenting with plasma arc torches for size reduction work. Their methods were employed in the AD and D hot cell with moderate success. The experimental work concluded with recommendations for further testing of other size reduction techniques. 11 figs., 6 tabs

  6. Development of decontamination technology for the decommissioned Bohunice A-1 nuclear power plant

    International Nuclear Information System (INIS)

    Krejci, F.; Majersky, D.; Solcanyi, M.; Sekely, S.; Kucharik, D.

    1991-01-01

    The main results of investigation into the decontamination technology for the equipment and buildings of the decommissioned A-1 nuclear power plant, achieved by the Nuclear Power Plants Research Institute in Trnava over the 1988-1990 period, are summarized. Mobile decontamination and recirculation equipment has been developed for pre-disassembling decontamination. A solution containing formic acid (19 g/l), EDTA-Na 4 (6 g/l) and thiourea (0.5 g/l) was used for decontamination of low-alloy steels; for materials from the steam generators and turbo-compressors, the decontamination factor (DF) of this solution was 30 to 150 per decontamination cycle. For high-alloy steels, a two-stage process comprising the use of an oxidation solution and a reduction solution appeared suitable. The oxidation solution contained potassium permanganate (0.6 g/l) and nitric acid (0.4 g/l), whereas the reduction solution, viz. Citrox 21, contained citric acid (0.5 g/l), oxalic acid (1.0 g/l) and EDTA-NA 4 (2.5 g/l). The DF is 10 to 50 in one oxidation-reduction cycle and 50-100 in two cycles. For the post-disassembling chemical decontamination, the contaminated material was cut into pieces 70 to 80 cm long, freed from grease and decontaminated chemically by submerging in the solution while applying treatment by ultrasound. A technology of electrochemical decontamination has also been developed. It appeared particularly suitable for structural materials of the primary coolant circuit comprising austenitic stainless steels and low-alloy steels after pre-disassembling chemical decontamination with remainders of the corrosion layer, and for structural materials of the secondary coolant circuit after chemical post-disassembling decontamination. Research in the field of decontamination of the building parts and of the outer surfaces of the structural materials concentrated mainly on the use of decontamination foams. Foaming solutions have been developed for the decontamination of PESL floors and

  7. Decontamination of polyvinylchloride- and rubber type flooring

    International Nuclear Information System (INIS)

    Kunze, S.

    1975-01-01

    These types, fabricated by mixing of the basic components, showed no relation between content of fillers and decontamination results. Decontamination results are partly poorer, if the flooring contains a high concentration of the filler, especially if the latter consists mainly of hydrophilic materials. The coloring of the floorings seems to have no influence on the decontamination but floorings with clearly separated patterns can not be recommended for nuclear facilities. Fabricated by chemical reactions between polymeres, vulcanization materials and fillers, the decontamination results depend definitely from the proper choice of the filler. Flooring types, containing lampblack, graphite, kaoline, barium sulfate and titanium oxide are easy to decontamine. Again, increasing contents of hydrophilic filler cause a fall off in the decontamination results. (orig.) [de

  8. INTEGRATED VERTICAL AND OVERHEAD DECONTAMINATION SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    M.A. Ebadian, Ph.D.

    1999-01-01

    This report summarizes the activities performed during FY98 and describes the planned activities for FY99. Accomplishments for FY98 include identifying and selecting decontamination, the screening of potential characterization technologies, development of minimum performance factors for the decontamination technology, and development and identification of Applicable, Relevant and Appropriate Regulations (ARARs).

  9. INTEGRATED VERTICAL AND OVERHEAD DECONTAMINATION SYSTEM

    International Nuclear Information System (INIS)

    Ebadian, M.A.

    1999-01-01

    This report summarizes the activities performed during FY98 and describes the planned activities for FY99. Accomplishments for FY98 include identifying and selecting decontamination, the screening of potential characterization technologies, development of minimum performance factors for the decontamination technology, and development and identification of Applicable, Relevant and Appropriate Regulations (ARARs)

  10. Excimer laser decontamination

    Science.gov (United States)

    Sentis, Marc L.; Delaporte, Philippe C.; Marine, Wladimir; Uteza, Olivier P.

    2000-04-01

    The application of excimer laser ablation process to the decontamination of radioactive surfaces is discussed. This technology is very attractive because it allows to efficiently remove the contaminated particles without secondary waste production. To demonstrate the capability of such technology to efficiently decontaminate large area, we studied and developed a prototype which include a XeCl laser, an optical fiber delivery system and an ablated particles collection cell. The main physical processes taking place during UV laser ablation will be explained. The influence of laser wavelength, pulse duration and absorption coefficient of material will be discussed. Special studies have been performed to understand the processes which limit the transmission of high average power excimer laser through optical fiber, and to determine the laser conditions to optimize the value of this transmission. An in-situ spectroscopic analysis of laser ablation plasma allows the real time control of the decontamination. The results obtained for painting or metallic oxides removal from stainless steel surfaces will be presented.

  11. Properties and solidification of decontamination wastes

    International Nuclear Information System (INIS)

    Davis, M.S.; Piciulo, P.L.; Bowerman, B.S.; Adams, J.W.; Milian, L.

    1983-01-01

    LWRs will require one or more chemical decontaminations to achieve their designed lifetimes. Primary system decontamination is designed to lower radiation fields in areas where plant maintenance personnel must work. Chemical decontamination methods are either hard (concentrated chemicals, approximately 5 to 25 weight percent) or soft (dilute chemicals less than 1 percent by weight). These methods may have different chemical reagents, some tailor-made to the crud composition and many methods are and will be proprietary. One factor common to most commercially available processes is the presence of organic acids and chelates. These types of organic reagents are known to enhance the migration of radionuclides after disposal in a shallow land burial site. The NRC sponsors two programs at Brookhaven National Laboratory that are concerned with the management of decontamination wastes which will be generated by the full system decontamination of LWRs. These two programs focus on potential methods for degrading or converting decontamination wastes to more acceptable forms prior to disposal and the impact of disposing of solidified decontamination wastes. The results of the solidification of simulated decontamination resin wastes will be presented. Recent results on combustion of simulated decontamintion wastes will be described and procedures for evaluating the release of decontamination reagents from solidified wastes will be summarized

  12. The restoration project : decontamination of facilities from chemical, biological and radiological contamination after terrorist action

    Energy Technology Data Exchange (ETDEWEB)

    Fingas, M.; Volchek, K.; Thouin, G.; Harrison, S.; Kuang, W. [Environment Canada, Ottawa, ON (Canada). Emergencies Science Div; Velicogna, D.; Hornof, M.; Punt, M. [SAIC Canada, Ottawa, ON (Canada); Payette, P.; Duncan, L.; Best, M.; Krishnan; Wagener, S.; Bernard, K.; Majcher, M. [Public Health Agency of Canada, Ottawa, ON (Canada); Cousins, T.; Jones, T. [Defence Research and Development Canada, Ottawa, ON (Canada)

    2005-07-01

    waste generated by decontamination is a major feasibility factor. Waste volume should be minimized to avoid high costs. It was suggested that extensive testing should be continued, as many of the ideas have not been tried except on ideal targets and surfaces. 11 refs., 14 figs.

  13. Decontamination of Rooibostea by radurization

    International Nuclear Information System (INIS)

    Holzapfel, W.H.

    1985-01-01

    The microbiological quality of a 'raw' agricultural commodity such as Rooibos tea is determined by a set of factors during harvesting and processing. Results suggest that a fermentation process takes place during processing, with members of the Enterobacteriaceae playing a dominant role. Against this background, as well as fluctuating hygienic conditions during processing, the high microbial population (10 7 to 5 x 10 8 /g) and even the possible presence of food-borne pathogens such as salmonellae, may be explaned. No real quarantee for the microbiological status of the product can be given, unless it is subjected to a terminal decontamination process (preferably after final packaging). Radurisation appears to be an ideal process for this purpose, and treatment at 8 kGy resulted in more than a 5000-fold (>99,9%) reduction of the microbial population. This was sufficient to eliminate all pathogens without harming the organoleptic quality of the product

  14. Developments in Decontamination Technologies of Military Personnel and Equipment

    Science.gov (United States)

    Sata, Utkarsh R.; Ramkumar, Seshadri S.

    Individual protection is important for warfighters, first responders and civilians to meet the current threat of toxic chemicals and chemical warfare (CW) agents. Within the realm of individual protection, decontamination of warfare agents is not only required on the battlefield but also in laboratory, pilot plants, production and agent destruction sites. It is of high importance to evaluate various decontaminants and decontamination techniques for implementing the best practices in varying scenarios such as decontamination of personnel, sites and sensitive equipment.

  15. Treatability studies for decontamination of Melton Valley Storage Tank supernate

    International Nuclear Information System (INIS)

    Arnold, W.D.; Fowler, V.L.; Perona, J.J.; McTaggart, D.R.

    1992-08-01

    Liquid low-level waste, primarily nitric acid contaminated with radionuclides and minor concentrations of organics and heavy metals, is neutralized with sodium hydroxide, concentrated by evaporation, and stored for processing and disposal. The evaporator concentrate separates into sludge and supernate phases upon cooling. The supernate is 4 to 5 mol/L sodium nitrate contaminated with soluble radionuclides, principally 137 Cs, 90 Sr, and 14 C, while the sludge consists of precipitated carbonates and hydroxides of metals and transuranic elements. Methods for treatment and disposal of this waste are being developed. In studies to determine the feasibility of removing 137 Cs from the supernates before solidification campaigns, batch sorption measurements were made from four simulated supernate solutions with four different samples of potassium hexacyanocobalt ferrate (KCCF). Cesium decontamination factors of 1 to 8 were obtained with different KCCF batches from a highly-salted supernate at pH 13. Decontamination factors as high as 50 were measured from supernates with lower salt content and pH, in fact, the pH had a greater effect than the solution composition on the decontamination factors. The decontamination factors were highest after 1 to 2 d of mixing and decreased with longer mixing times due to decomposition of the KCCF in the alkaline solution. The decontamination factors decreased with settling time and were lower for the same total contact time (mixing + settling) for the longer mixing times, indicating more rapid KCCF decomposition during mixing than during settling. There was no stratification of cesium in the tubes as the KCCF decomposed

  16. Development of peelable films for decontamination and their performances

    International Nuclear Information System (INIS)

    Yang Enbo; Xu Baolan; Zhao Xiuyan

    1990-01-01

    Two kinds of peelable films have been developed which can be coated on surface contaminated by radioactivity for decontamination purposes. Very high levels of radioactive decontamination, especially on smooth surface, are obtained after one application. 90-99% decontamination based on initial activity can be obtained for stainless steel, PVC floor and glass

  17. Ontario Hydro decontamination experience

    Energy Technology Data Exchange (ETDEWEB)

    Lacy, C S; Patterson, R W; Upton, M S [Chemistry and Metallurgy Department, Central Production Services, Ontario Hydro, ON (Canada)

    1991-04-01

    Ontario Hydro currently operates 18 nuclear electric generating units of the CANDU design with a net capacity of 12,402 MW(e). An additional 1,762 MW(e) is under construction. The operation of these facilities has underlined the need to have decontamination capability both to reduce radiation fields, as well as to control and reduce contamination during component maintenance. This paper presents Ontario Hydro decontamination experience in two key areas - full heat transport decontamination to reduce system radiation fields, and component decontamination to reduce loose contamination particularly as practised in maintenance and decontamination centres. (author)

  18. Reactive decontamination formulation

    Science.gov (United States)

    Giletto, Anthony [College Station, TX; White, William [College Station, TX; Cisar, Alan J [Cypress, TX; Hitchens, G Duncan [Bryan, TX; Fyffe, James [Bryan, TX

    2003-05-27

    The present invention provides a universal decontamination formulation and method for detoxifying chemical warfare agents (CWA's) and biological warfare agents (BWA's) without producing any toxic by-products, as well as, decontaminating surfaces that have come into contact with these agents. The formulation includes a sorbent material or gel, a peroxide source, a peroxide activator, and a compound containing a mixture of KHSO.sub.5, KHSO.sub.4 and K.sub.2 SO.sub.4. The formulation is self-decontaminating and once dried can easily be wiped from the surface being decontaminated. A method for decontaminating a surface exposed to chemical or biological agents is also disclosed.

  19. Ontario Hydro decontamination experience

    International Nuclear Information System (INIS)

    Lacy, C.S.; Patterson, R.W.; Upton, M.S.

    1991-01-01

    Ontario Hydro currently operates 18 nuclear electric generating units of the CANDU design with a net capacity of 12,402 MW(e). An additional 1,762 MW(e) is under construction. The operation of these facilities has underlined the need to have decontamination capability both to reduce radiation fields, as well as to control and reduce contamination during component maintenance. This paper presents Ontario Hydro decontamination experience in two key areas - full heat transport decontamination to reduce system radiation fields, and component decontamination to reduce loose contamination particularly as practised in maintenance and decontamination centres. (author)

  20. Decontamination of steam generators at Loviisa NPS - The decision making and the results

    International Nuclear Information System (INIS)

    Wahlstroem, Bjoern G.

    1984-01-01

    In 1980, during the annual inspections at Loviisa 1, 440 MWe PWR unit, some minor faults in the welding seams of the water chambers in two of the six steam generators were indicated. This led to enlarged inspection work and to thousands of working hours inside the steam generators. The plant had been three years in operation, so the dose rates in the steam generators were rather high. In this case it turned out, that a formal radiation protection optimization procedure would not give the answer on how to go ahead, as there were several practical and psychological factors influencing the decision making process. Anyhow, the result was that a decontamination apparatus was urgently planned and constructed, and advice on tested decontamination chemicals was received from the plant supplier. Using the decontamination machine with alternating basic and acid solutions, a decontamination factor of DF = 300 was reached, and the repair work could be performed without any restrictions on working time. This paper points out some limiting factors in the decision making process and describes the decontamination equipment, the decontamination solutions and the programme. The cost per saved collective dose unit is also calculated. (author)

  1. Reactor component chemical decontamination-developments in waste handling and disposal

    International Nuclear Information System (INIS)

    Papesch, R.; Atwood, K.L.

    1989-01-01

    Because of restrictive limits on man-rem exposure in European nuclear plants, a company has developed and applied a number of chemical decontamination techniques for components that must be periodically maintained. These techniques are particularly effective for components that can be placed in a decontamination bath for dose reduction prior to performing maintenance. The cleaning technique has the ability to achieve decontamination factors of at least 20 and in some cases much greater. For components with before cleaning dose rates of between 1 to as high as 80 R/hr, significant man-rem reductions are achieved when hundreds of manhours may be required to complete required component maintenance. Transferring this solvent technology to the U.S. required a program to develop solidification formulas to allow the solvent wastes to be disposed of in accordance with regulations and in a cost effective manner. This paper demonstrates in chemical decontaminations with small liquid volume systems that concentrated decontamination solvents can be employed to achieve high decontamination factors

  2. A scaffold easy to decontaminate

    International Nuclear Information System (INIS)

    Mourek, D.

    1992-01-01

    The conventional scaffold used in the assembling work and in revisions of technological facilities at nuclear power plants has many drawbacks. The most serious of them are a high amount of radioactive waste arising from the decontamination (planing) of the floor timber and from the discarding of damaged irreparable parts, and a considerable corrosion of the carbon steel supporting structure after the decontamination. A detailed description is given of a novel scaffold assembly which can be decontaminated and which exhibits many assets, in particular a good mechanical resistance (also to bad weather), a lower weight, and the use of prepreg floor girders for the construction of service platforms or scaffold bridges which can readily be assembled from the pressed pieces in a modular way. (Z.S.). 4 figs., 4 refs

  3. Proposal of biostimulation for hexachlorocyclohexane (HCH)-decontamination and characterization of culturable bacterial community from high-dose point HCH-contaminated soils.

    Science.gov (United States)

    Dadhwal, M; Singh, A; Prakash, O; Gupta, S K; Kumari, K; Sharma, P; Jit, S; Verma, M; Holliger, C; Lal, R

    2009-02-01

    To locate a high-dose point hexachlorocyclohexane (HCH)-contaminated site, to identify HCH-degrading bacteria in it and assay HCH-decontamination by biostimulation. Bacteria were isolated by serial dilution method from HCH-contaminated soil samples collected from areas near an HCH-manufacturing unit and its dumpsite in North India. After confirming the presence of indigenous HCH-degraders (seven of 24 strains), an ex situ biostimulation experiment was conducted. For this, residue levels in soil were diluted by mixing with pristine garden soil and aeration, moisture and nutrients were provided intermittently. This soil was monitored for reduction in Sigma-HCH (sum of alpha-, beta-, gamma- and delta-HCH) levels and stimulation of HCH-degraders. Experiments were conducted twice, in March-April (c. 75 microg Sigma-HCH g(-1) soil) and October-November 2006 (c. 280 microg Sigma-HCH g(-1) soil) at 26-30 degrees C. Sigma-HCH levels were reduced to decontamination via aeration, addition of nutrients and moisture, of the indigenous population. The study demonstrates that biostimulation of indigenous HCH-degrading microbial population can be used for decontamination of chronically HCH-contaminated sites.

  4. Decontamination of acid mine water from Ronneburg/Thueringen which is high in sulfates and metals using sulfate-reducing bacteria. Final report of the preliminary phase

    International Nuclear Information System (INIS)

    Hard, B.; Friedrich, S.

    1995-01-01

    The mining in Eastern Europe, particularly in East-Germany, is a major source of pollution to the surrounding areas of the mines. With the end of the cold war the demand for uranium has drastically declined. Many of the pits have therefore been closed down or are in the process of closure such as the uranium mine in Ronneburg in Thueringen. One major problem is the safe-making of the pits and dumps as they are highly radioactive through naturally occurring uranium and other radioactive elements. Because of the leaching process through bacteria, drainage water is very acidic, with pH-values between 1-2. The water is very rich in magnesium, iron and aluminium sulfate. Here the application of a microbial process to decontaminate acid mine drainage was investigated. Decontamination of the water includes: - Increase in pH - decrease in sulfate concentrations - minimization of the metal and radionuclide load. Sulfate-reducing bacteria seem suitable for this process. In order for such a microbial process to be economically viable a cheap and widely available electron donar has to be used eg. methanol. The work carried out reports on the isolation, characterization and physiology of sulfate-reducing methylotrophic bacteria and their suitability for a decontamination process of sulfuric acid uranium mine water. (orig.) [de

  5. Electrochemical decontamination system for actinide processing gloveboxes

    International Nuclear Information System (INIS)

    Wedman, D.E.; Lugo, J.L.; Ford, D.K.; Nelson, T.O.; Trujillo, V.L.; Martinez, H.E.

    1998-03-01

    An electrolytic decontamination technology has been developed and successfully demonstrated at Los Alamos National Laboratory (LANL) for the decontamination of actinide processing gloveboxes. The technique decontaminates the interior surfaces of stainless steel gloveboxes utilizing a process similar to electropolishing. The decontamination device is compact and transportable allowing it to be placed entirely within the glovebox line. In this way, decontamination does not require the operator to wear any additional personal protective equipment and there is no need for additional air handling or containment systems. Decontamination prior to glovebox decommissioning reduces the potential for worker exposure and environmental releases during the decommissioning, transport, and size reduction procedures which follow. The goal of this effort is to reduce contamination levels of alpha emitting nuclides for a resultant reduction in waste level category from High Level Transuranic (TRU) to low Specific Activity (LSA, less than or equal 100 nCi/g). This reduction in category results in a 95% reduction in disposal and disposition costs for the decontaminated gloveboxes. The resulting contamination levels following decontamination by this method are generally five orders of magnitude below the LSA specification. Additionally, the sodium sulfate based electrolyte utilized in the process is fully recyclable which results in the minimum of secondary waste. The process bas been implemented on seven gloveboxes within LANL's Plutonium Facility at Technical Area 55. Of these gloveboxes, two have been discarded as low level waste items and the remaining five have been reused

  6. Decontamination manual of RI handling laboratory

    International Nuclear Information System (INIS)

    Wadachi, Yoshiki

    2004-01-01

    Based on experiences in Japan Atomic Energy Research Institute (JAERI), the essential and practical knowledge of radioactive contamination and its decontamination, and the method and procedure of floor decontamination are described for researcher and managing person in charge of handling radioisotopes (RI) in RI handling laboratories. Essential knowledge concerns the uniqueness of solid surface contamination derived from RI half lives and quantities, surface contamination density limit, and mode/mechanism of contamination. The principle of decontamination is a single conduct with recognition of chemical form of the RI under use. As the practical knowledge, there are physical and chemical methods of solid surface decontamination. The latter involves use of inorganic acids, chelaters and surfactants. Removal and replacement of contaminated solid like floor material are often effective. Distribution mapping of surface contamination can be done by measuring the radioactivity in possibly contaminated areas, and is useful for planning of effective decontamination. Floor surface decontamination is for the partial and spread areas of the floor. It is essential to conduct the decontamination with reagent from the highly to less contaminated areas. Skin decontamination with either neutral detergent or titanium oxide is also described. (N.I.)

  7. [Decontamination of chemical and biological warfare agents].

    Science.gov (United States)

    Seto, Yasuo

    2009-01-01

    Chemical and biological warfare agents (CBWA's) are diverse in nature; volatile acute low-molecular-weight toxic compounds, chemical warfare agents (CWA's, gaseous choking and blood agents, volatile nerve gases and blister agents, nonvolatile vomit agents and lacrymators), biological toxins (nonvolatile low-molecular-weight toxins, proteinous toxins) and microbes (bacteria, viruses, rickettsiae). In the consequence management against chemical and biological terrorism, speedy decontamination of victims, facilities and equipment is required for the minimization of the damage. In the present situation, washing victims and contaminated materials with large volumes of water is the basic way, and additionally hypochlorite salt solution is used for decomposition of CWA's. However, it still remains unsolved how to dispose large volumes of waste water, and the decontamination reagents have serious limitation of high toxicity, despoiling nature against the environments, long finishing time and non-durability in effective decontamination. Namely, the existing decontamination system is not effective, nonspecifically affecting the surrounding non-target materials. Therefore, it is the urgent matter to build up the usable decontamination system surpassing the present technologies. The symposiast presents the on-going joint project of research and development of the novel decontamination system against CBWA's, in the purpose of realizing nontoxic, fast, specific, effective and economical terrorism on-site decontamination. The projects consists of (1) establishment of the decontamination evaluation methods and verification of the existing technologies and adaptation of bacterial organophosphorus hydrolase, (2) development of adsorptive elimination technologies using molecular recognition tools, and (4) development of deactivation technologies using photocatalysis.

  8. The feasibility study of hot cell decontamination by the PFC spray method

    International Nuclear Information System (INIS)

    Hui-Jun Won; Chong-Hun Jung; Jei-Kwon Moon

    2008-01-01

    module. A performance test on each module was executed and the results have been reported. A combined test of the four modules, however, has not been performed as yet. The main objective of the present study is to demonstrate the feasibility of the full PFC spray decontamination process. Decontamination of the inside of the IMEF hot cell by the PFC spray method was also performed. PFC spray decontamination process was demonstrated by using a surrogate wall contaminated with Eu 2 O 3 powder. The spray pressure was 41 kgf/cm 2 , the orifice diameter was 0.2 mm and the spray velocity was 0.2 L/min. And, the decontaminated area was 100 cm 2 . From previous test results, we found that the decontamination factor of the PFC spray method was in the range from 9.6 to 62.4. When the decontamination efficiency of Co-60 was high, then the decontamination efficiency of Cs-137 was also high. As the surface roughness of the specimen increased, the PFC spray decontamination efficiency decreased. Inferring from the previous results, the surface of the surrogate wall was cleaned by the PFC spray method. The vacuum cup of the collection module operated well and gathered more than 99 % of the PFC solution. Also, filtration and distillation modules operated well. All the filtered PFC solution flowed to the storage chamber where some of the PFC solution was distilled. The coolant of the distillation module was a dry ice. And, the recycled solution was transferred to the spray module by a high pressure pump. To evaluate the PFC spray decontamination efficiency, a smear device was fabricated and operated by a manipulator. Before and after decontamination, a smear test was performed. The tested area was 100 cm 2 and the radioactivity was estimated indirectly by measuring the radioactivity of the filter paper. The average decontamination factor was in the range between 10 and 15. One application time was 2 minutes. The sprayed PFC solution was collected by the vacuum cup and it was stored in the

  9. Development of chemical decontamination process with sulfuric acid-cerium (IV) for decommissioning

    International Nuclear Information System (INIS)

    Suwa, Takeshi; Kuribayashi, Nobuhide; Tachikawa, Enzo

    1988-01-01

    The electrolytic regeneration of Ce 4+ from Ce 3+ , which is required to achieve a high decontamination factor (DF) in this process, has been investigated. A calculating model was derived for the regenerating current required during the decontamination as a function of dissolution rate of crud, corrosion rate (R c ), current efficiency (η e ) and characteristics of decontamination loop. From the above calculation, it was found that the current was mainly governed by R c and η e . A condition to obtain a high DF at low R c and high η e has been found experimentally by use of a mixture of Ce 3+ at the ratio of Ce 4+ /Ce 3+ = 0.1 ∼ 0.2. The desired values to be η e ≥ 80 % at above 50 A/m 2 was obtained under the flow rate above 300 cm/min and Ce 3+ concentration above 10 x 10 -3 M at 60 deg C using the dual-cylindrical type cell. The current efficiency was also investigated with cells of various geometries. The present decontamination process has been proposed as a system decontamination process, which is essentially a single-step decontamination process for Cr-rich oxides. (author)

  10. Chemical decontamination of metals

    International Nuclear Information System (INIS)

    Partridge, J.A.; Lerch, R.E.

    1979-10-01

    A metal decontamination process based upon removal of contamination by treatment with a cerium (IV)-nitric acid solution (or other redox agent in nitric acid) is feasible and highly promising. The technique is effective in dissolving the surface layer of stainless steel. Dissolution rates of approximately 1.5 mils/h were demonstrated with cerium (IV)-nitric acid solutions. Removal of plutonium contamination from stainless steel was demonstrated in laboratory tests, in which activity levels were reduced from greater than 5 x 10 5 counts per minute to nondetectable levels in approximately one hour at 90 0 C. Removal of paint from stainless steel surfaces was also demonstrated. Advantages of this process over other chemical solutions include: (1) The solutions are not high salt systems; therefore, there is potentially less waste generated. (2) Cerium(IV) in nitric acid is a good dissolution agent for plutonium oxide. (3) Regeneration of Ce(IV) during the decontamination is accomplished by electrolysis. (4) The process should be effective for irregularly shaped equipment. (5) It could be effective as a spray or a flow-through system. 13 figures

  11. Chemical decontamination method

    International Nuclear Information System (INIS)

    Nishiwaki, Hitoshi.

    1996-01-01

    Metal wastes contaminated by radioactive materials are contained in a rotational decontamination vessel, and the metal wastes are rotated therein while being in contact with a slight amount of a decontamination liquid comprising a mineral acid. As the mineral acid, a mixed acid of nitric acid, hydrochloric acid and fluoric acid is preferably used. Alternatively, chemical decontamination can also be conducted by charging an acid resistant stirring medium in the rotational decontamination vessel. The surface of the metal wastes is uniformly covered by the slight amount of decontamination liquid to dissolve the surface layer. In addition, heat of dissolution generated in this case is accumulated in the inside of the rotational decontamination vessel, the temperature is elevated with no particular heating, thereby enabling to obtain an excellent decontamination effect substantially at the same level as in the case of heating the liquid to 70degC in a conventional immersion decontamination method. Further, although contact areas between the metal wastes and the immersion vessel are difficult to be decontaminated in the immersion decontamination method, all of areas can be dissolved uniformly in the present invention. (T.M.)

  12. Soil decontamination at Rocky Flats

    International Nuclear Information System (INIS)

    Olsen, R.L.; Hayden, J.A.; Alford, C.E.; Kochen, R.L.; Stevens, J.R.

    1979-01-01

    A soils decontamination project was initiated, to remove actinides from soils at Rocky Flats. Wet screening, attrition scrubbing with Calgon at high pH, attrition scrubbing at low pH, and cationic flotation were investigated. Pilot plant studies were carried out. Conceptual designs have been generated for mounting the process in semi-trailers

  13. Foam process for application of decontamination agents

    International Nuclear Information System (INIS)

    Harris, J.M.; Miller, J.R.; Frazier, R.S.; Walter, J.H.

    1982-01-01

    This paper presents the results and observations of a study performed by the authors to parametrically evaluate the performance characteristics of a foam process for application of decontamination agents. The initial tests were established to assess foam quality. Subsequent tests determined the ability of the foam as a carrier of chemical systems, and established system operating parameters. The technique was then applied in an actual decontamination task to verify effectiveness of these established parameters and to determine decontamination reduction factors. 4 figures, 5 tables

  14. Decontamination device for pipeline

    International Nuclear Information System (INIS)

    Harashina, Heihachi.

    1994-01-01

    Pipelines to be decontaminated are parts of pipelines contaminated with radioactive materials, and they are connected to a fluid transfer means (for example, a bladeless pump) and a ball collector by way of a connector. The fluid of a mixture of chemical decontaminating liquid and spheres is sent into pipelines to be decontaminated. The spheres are, for example, heat resistant porous hard or soft rubber spheres. The fluid discharged from the pipelines to be decontaminated are circulated by way of bypassing means. The inner surface of the pipelines is decontaminated by the circulation of the fluid. When the bypass means is closed, the fluid discharged from the pipelines to be decontaminated is sent to the ball collector, and the spheres are captured by a hopper. Further, the liquid is sent to the filtrating means to filter the chemical contaminating liquid, and sludges contained in the liquid are captured. (I.N.)

  15. Radiocesium concentrations in soil and leaf after decontamination practices in a forest plantation highly polluted by the Fukushima accident.

    Science.gov (United States)

    López-Vicente, Manuel; Onda, Yuichi; Takahashi, Junko; Kato, Hiroaki; Chayama, Shinya; Hisadome, Keigo

    2018-08-01

    Owing to the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident a vast amount of radiocesium was released polluting the land. Afterwards, a variety of decontamination practices has been done, reducing the ambient dose rates. In this study we evaluated the effectiveness of eight forest decontamination practices by means of monitoring the radiocesium ( 137 Cs) concentration in soil and leaf samples, and the daily discharge rates in ten plots during 27 months (May 2013-July 2015). A forest plantation located 16 km southwest to the FDNPP and within the exclusion area was selected. Radiocesium concentrations were analysed using a germanium gamma ray detector. The differences in radiocesium activities between the different plots were statistically significant (p soil and leaf fraction were 96.6% and 3.4%. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. A study on dry decontamination using ion exchange polymer

    International Nuclear Information System (INIS)

    Jung, Ki Jung; Ahn, Byung Gil

    1997-12-01

    Through the project of A study on dry decontamination using ion exchange polymer , the followings were investigated. 1. Highly probable decontamination technologies for the decontamination were investigated. 2. Development of gel type decontamination agent using ion-exchange resin powder (mixed type) as an ion exchanger. 3. Manufacturing of contaminated specimens (5 kinds) with Cs-137 solution and dust / Cs-137 solution. 4. Decontamination performance evaluation of the manufactured agent. 5. Analysis of composition (XRF) and the structure of surface of specimens (optic micrography). (author). 20 refs., 11 figs

  17. Study of Thorium Phosphate Diphosphate (TPD) formation in nitric medium for the decontamination of high activity actinides bearing effluents

    International Nuclear Information System (INIS)

    Rousselle, Jerome

    2004-01-01

    Considering several activities in the nuclear industry and research, several low-level liquids wastes (LLLW) containing actinides in nitric medium must be decontaminated before being released in the environment. These liquid wastes mainly contain significant amounts of uranium(VI), neptunium(V) and plutonium(IV). In this work, two chemical ways were studied to decontaminate LLLW then to incorporate simultaneously uranium, neptunium and plutonium in the Thorium Phosphate Diphosphate (TPD). Both ways started from a nitric solution containing thorium and the actinides considered, present at their lower stable oxidation state. The first way consisted in the initial precipitation of actinide and thorium mixed oxalate. After drying the mixture containing the powder and phosphoric acid under dried argon, a poly-phase system was obtained. It was mainly composed by a thorium-actinide oxalate-phosphate. This mixture was transformed into a TPDAn solid solution (An = U, Np and/or Pu) by heating treatment at 1200 deg. C under inert atmosphere. The second way consisted in the precipitation of a precursor of TPD, identified as the Thorium Phosphate Hydrogen Phosphate loaded with the actinides considered. The gel initially formed by mixing concentrated phosphoric acid solution with the nitric actinide solution was heated at 90 - 160 deg. C in a closed PTFE container for several weeks. It led to the TPDAn solid solutions after heating at 1100 deg. C in air or under inert argon. The efficiency of both processes was evaluated through the determination of the decontamination for each actinide considered. Considering the encouraging results obtained for both kinds of processes, some complementary studies are now required before performing the effective decontamination of real Low-Level Liquid Waste using one of the methods proposed. (author) [fr

  18. Strippable gel for decontamination of contaminated metallic surfaces

    International Nuclear Information System (INIS)

    Banerjee, D.; Sandhya, U.; Khot, S.A.; Srinivas, C.; Wattal, P.K.

    2013-01-01

    Periodic decontamination of radioactive laboratories including fume hoods, glove boxes and all surfaces used for handling, processing and transporting radioactive materials is mandatory in all nuclear installations as this reduces spread of contamination and decreases total man rem exposure. Conventionally, chemical decontaminating agents or surfactant solutions are used for this purpose. However, this approach leads to generation of large volume of secondary radioactive waste. The use of strippable gel is an attractive alternative with low secondary waste generation particularly where removal of loose or weakly fixed contamination is necessary and also when the decontaminated material are to be reused, for e.g. decontamination of fume hoods, glove boxes, transport casks, spent fuel storage racks, control rod drive transport containers etc. Literature on gel formulations is scarce and mostly in the patent form. The sustained effort on gel formulation development has resulted in a basic gel formulation. The gel is a highly viscous water-based organic polymer, particularly suitable for application on vertical surfaces including difficult to reach metallic surfaces of complex geometry and not just limited to horizontal surfaces. The gel can be easily applied on contaminated surfaces by brushing or spraying. Curing of the gel is complete within 16-24 hours under ambient conditions and can then be removed by peeling as a dry sheet. While curing, the contaminants are trapped in gel either physically or chemically depending upon the nature of the contaminant. Salient features of cured gel include that it is water soluble and can be disposed off after immobilization in cement. Decontamination performance of the gel was initially evaluated by applying it on SS planchettes contaminated with known amount of radionuclides such as Cs(I), Co(II) and Ce(III). The measured decontamination factor was found to be in the range of 50-500, lowest for Ce(III) and highest for Co

  19. Nuclear reactor vessel decontamination systems

    International Nuclear Information System (INIS)

    McGuire, P. J.

    1985-01-01

    There is disclosed in the present application, a decontamination system for reactor vessels. The system is operatable without entry by personnel into the contaminated vessel before the decontamination operation is carried out and comprises an assembly which is introduced into the vertical cylindrical vessel of the typical boiling water reactor through the open top. The assembly includes a circular track which is centered by guideways permanently installed in the reactor vessel and the track guides opposed pairs of nozzles through which water under very high pressure is directed at the wall for progressively cutting and sweeping a tenacious radioactive coating as the nozzles are driven around the track in close proximity to the vessel wall. The whole assembly is hoisted to a level above the top of the vessel by a crane, outboard slides on the assembly brought into engagement with the permanent guideways and the assembly progressively lowered in the vessel as the decontamination operation progresses. The assembly also includes a low pressure nozzle which forms a spray umbrella above the high pressure nozzles to contain radioactive particles dislodged during the decontamination

  20. Pipe and hose decontamination apparatus

    International Nuclear Information System (INIS)

    Fowler, D.E.

    1985-01-01

    A pipe and hose decontamination apparatus is disclosed using freshly filtered high pressure Freon solvent in an integrated closed loop to remove radioactive particles or other contaminants from items having a long cylindrical geometry such as hoses, pipes, cables and the like. The pipe and hose decontamination apparatus comprises a chamber capable of accomodating a long cylindrical work piece to be decontaminated. The chamber has a downward sloped bottom draining to a solvent holding tank. An entrance zone, a cleaning zone and an exit drying zone are defined within the chamber by removable partitions having slotted rubber gaskets in their centers. The entrance and exit drying zones contain a horizontally mounted cylindrical housing which supports in combination a plurality of slotted rubber gaskets and circular brushes to initiate mechanical decontamination. Solvent is delivered at high pressure to a spray ring located in the cleaning zone having a plurality of nozzles surrounding the work piece. The solvent drains into a solvent holding tank located below the nozzles and means are provided for circulating the solvent to and from a solvent cleaning, distilling and filter unit

  1. Decontamination of body surface

    International Nuclear Information System (INIS)

    Harase, Chieko.

    1989-01-01

    There are two important points for an effective application of decontamination procedures. One is the organizing method of responsible decontamination teams. The team should be directed by medical doctor with the knowledge of decontamination of radionuclides. The other point is the place of application of the decontamination. Hospitals and clinics, especially with a department of nuclear medicine, or specialized units such as an emergency medical center are preferable. Before decontamination procedures are initiated, adequate monitoring of the body surface should be undertaken by a competent person in order to demarcate the areas which are contaminated. There are fundamental principles which are applicable to all decontamination procedures. (1) Precautions must always be taken to prevent further spread of contamination during decontamination operations. (2) Mild decontamination methods should be tried before resorting to treatment which can damage the body surface. The specific feature of each contamination varies widely in radionuclides involved, place and area of the contamination, condition of the contaminated skin such as whether the skin is wounded or not, and others. Soap and water are usually good detergents in most cases. If they fail, orange oil cream (SUPERDECONCREAM, available from Tokyo Engineering Co.) specially prepared for decontamination of radionuclides of most fission and corrosion products may be used. Contaminated hair should be washed several times with an efficient shampoo. (author)

  2. Decontamination technology assessment

    International Nuclear Information System (INIS)

    Allen, R.P.; Konzek, G.J.; Schneider, K.R.; Smith, R.I.

    1988-10-01

    This study identifies and technically assesses foreign decontamination and decommissioning (D and D) technology developments that may represent significant improvements over D and D technology currently available or under development in the United States. Technology need areas for nuclear power reactor decommissioning operations were identified and prioritized using the results of past light water reactor (LWR) decommissioning studies to quantitatively evaluate the potential for reducing cost and decommissioning worker radiation dose for each major decommissioning activity. Based on these identified needs, current foreign D and D technologies of potential interest to the US were identified through personal contacts and the collection and review of an extensive body of D and D literature. These technologies were then assessed qualitatively to evaluate their uniqueness, potential for a significant reduction in D and D costs and/or worker radiation dose, development status, and other factors affecting their value and applicability to US needs. 4 refs

  3. Plutonium decontamination studies using Reverse Osmosis

    International Nuclear Information System (INIS)

    Plock, C.E.; Travis, T.N.

    1980-01-01

    Water in batches of 45 gallons each, from a creek crossing the Rocky Flats Plant, was transferred to the Reverse Osmosis (RO) laboratory for experimental testing. The testing involved using RO for plutonium decontamination. For each test, the water was spiked with plutonium, had its pH adjusted, and was then processed by RO. At a water recovery level of 87%, the plutonium decontamination factors ranged from near 100 to 1200, depending on the pH of the processed water

  4. Summary of decontamination cover manufacturing experience

    International Nuclear Information System (INIS)

    Ulrich, G.B.; Berry, H.W.

    1995-02-01

    Decontamination cover forming cracks and vent cup assembly leaks through the decontamination covers were early manufacturing problems. The decontamination cover total manufacturing process yield was as low as 55%. Applicable tooling and procedures were examined. All manufacturing steps from foil fabrication to final assembly leak testing were considered as possible causes or contributing factors to these problems. The following principal changes were made to correct these problems: (1) the foil annealing temperature was reduced from 1375 degrees to 1250 degrees C, (2) the decontamination cover fabrication procedure (including visual inspection for surface imperfections and elimination of superfluous operations) was improved, (3) the postforming dye penetrant inspection procedure was revised for increased sensitivity, (4) a postforming (prewelding) 1250 degrees C/1 h vacuum stress-relief operation was added, (5) a poststress relief (prewelding) decontamination cover piece-part leak test was implemented, (6) the hold-down fixture used during the decontamination cover-to-cup weld was modified, and concomitantly, and (7) the foil fabrication process was changed from the extruding and rolling of 63-mm-diam vacuum arc-remelted ingots (extrusion process) to the rolling of 19-mm-square arc-melted drop castings (drop cast process). Since these changes were incorporated, the decontamination cover total manufacturing process yield has been 91 %. Most importantly, more than 99% of the decontamination covers welded onto vent cup assemblies were acceptable. The drastic yield improvement is attributed primarily to the change in the foil annealing temperature from 1375 degrees to 1250 degrees C and secondarily to the improvements in the decontamination cover fabrication procedure

  5. Radiocesium decontamination of a riverside in Fukushima, Japan.

    Science.gov (United States)

    Nishikiori, Tatsuhiro; Suzuki, Satoshi

    2017-10-01

    Extensive decontamination measures have been implemented in the area affected by the Fukushima Dai-ichi nuclear disaster. Typical decontamination measures, such as removing topsoil of several centimeters in depth, are not suitable for rivers where contaminated sediments have been deposited. A decontamination measure was tested that considered the spatial distribution of radiocesium at the lower part of a tributary of the Abukuma River in Fukushima. The radiocesium distribution in the flood channel was vertically and horizontally highly heterogeneous. In some parts, the activity concentration was high (>10 kBq/kg for 137 Cs) even at depths of 25 cm in the sediment. This may be due to plant growth in the flood channel favoring the deposition of sediment with high activity concentration. On the basis of the radiocesium distribution, the flood channel sediment was removed to a depth of 15-35 cm, which accumulated the most radiocesium (>3.0 kBq/kg for the sum of 134 Cs and 137 Cs). The upper 5 cm of soil was removed from the dike slopes. The river bed was not decontaminated because the activity concentration was low (decontamination measure reduced the air dose rate by a factor of approximately two, demonstrating the effectiveness of our measures. Annual external doses were calculated for when this part of the dike and the flood channel is used for commuting to school and outdoor education. The doses during the activities at the test site accounted for only 1-2% of the value during daily life in the surrounding area, indicating that radiation exposure during riverside activities is limited. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Decontamination of floor surfaces

    International Nuclear Information System (INIS)

    Smirous, F.

    1983-01-01

    Requirements are presented put on the surfaces of floors of radiochemical workplaces. The mechanism is described of retaining the contaminant in the surface of the flooring, ways of reducing the hazards of floor surface contamination, decontamination techniques and used decontamination agents. (J.P.)

  7. Stainless steel decontamination manipulators

    International Nuclear Information System (INIS)

    Sullivan, R.J.

    1986-01-01

    Three, large-volume coverage manipulator systems were designed and built for the Defense Water Processing Facility at the Savannah River Laboratory. These stainless steel systems will be used for high-pressure spray decontamination of waste containers and large process equipment modules. Each system has a manipulator arm, folding boom, and vertical drive and guide structure. Handling capacity is 45 kg, horizontal reach is 4.6 m with a 180-deg swing motion, and the vertical travel is 6 m. The system is remotely removable and replaceable in modules using an overhead crane and an impact wrench. The manipulator arm has seven motions: Shoulder rotation and pivot, elbow pivot, wrist pivot and rotation, and grip open-close. All motions are variable speed and are slip-clutch protected to prevent overloading from external forces (collisions)

  8. Granulated decontamination formulations

    Science.gov (United States)

    Tucker, Mark D.

    2007-10-02

    A decontamination formulation and method of making that neutralizes the adverse health effects of both chemical and biological compounds, especially chemical warfare (CW) and biological warfare (BW) agents, and toxic industrial chemicals. The formulation provides solubilizing compounds that serve to effectively render the chemical and biological compounds, particularly CW and BW compounds, susceptible to attack, and at least one reactive compound that serves to attack (and detoxify or kill) the compound. The formulation includes at least one solubilizing agent, a reactive compound, a sorbent additive, and water. A highly adsorbent sorbent additive (e.g., amorphous silica, sorbitol, mannitol, etc.) is used to "dry out" one or more liquid ingredients into a dry, free-flowing powder that has an extended shelf life, and is more convenient to handle and mix in the field.

  9. Glovebox decontamination technology comparison

    International Nuclear Information System (INIS)

    Quintana, D.M.; Rodriguez, J.B.; Cournoyer, M.E.

    1999-01-01

    Reconfiguration of the CMR Building and TA-55 Plutonium Facility for mission requirements will require the disposal or recycle of 200--300 gloveboxes or open front hoods. These gloveboxes and open front hoods must be decontaminated to meet discharge limits for Low Level Waste. Gloveboxes and open front hoods at CMR have been painted. One of the deliverables on this project is to identify the best method for stripping the paint from large numbers of gloveboxes. Four methods being considered are the following: conventional paint stripping, dry ice pellets, strippable coatings, and high pressure water technology. The advantages of each technology will be discussed. Last, cost comparisons between the technologies will be presented

  10. Influence of Decontamination

    International Nuclear Information System (INIS)

    Knaack, Michael

    2016-01-01

    This paper describes the influence of several decontamination techniques on the decommissioning of nuclear facilities. There are different kinds of decontamination methods like mechanical and chemical processes. The techniques specified, and their potential to change measured characteristics like the isotope vector of the contamination is demonstrated. It is common for all these processes, that the contamination is removed from the surface. Slightly adhered nuclides can be removed more effectively than strongly sticking nuclides. Usually a mixture of these nuclides forms the contamination. Problematically any kind of decontamination will influence the nuclide distribution and the isotope vector. On the one hand it is helpful to know the nuclide distribution and the isotope vector for the radiological characterization of the nuclear facility and on the other hand this information will be changed in the decontamination process. This is important especially for free release procedures, radiation protection and waste management. Some questions on the need of decontamination have been discussed. (authors)

  11. Decontamination experiments for stainless steel decommissioned components

    International Nuclear Information System (INIS)

    Stefanescu, D.; Radulescu, M.; Dragomir, M.; Velciu, L.; Dinu, A.

    2001-01-01

    This paper presents the factors which influence the decontamination conditions using the steps of CONAP process. This four phases process (alkaline pre-treatment , an oxidation phase with potassium permanganate in acid environment, a dissolution phase using a complexing agent, a rinsing phase) has been used for decontamination to recycle the stainless steel 304 L and 403 m. The attraction of this process results from the following reasons: - the volume of radioactive sludge is low comparatively with the original volume of the solutions; - the separation of the activity from the solution is very effective; - time of exposure is reduced; - it is not necessary to process the solution through evaporators. During decommissioning decontamination is used to reduce radiation field by removing some of the fission and activation products contained in deposits and oxide films to minimize the radiation exposure of the personnel and public. In this context, this hard decontamination yields the materials at a radioactivity level fulfilling the repository requirements. (authors)

  12. Low concentration NP preoxidation condition for PWR decontamination

    International Nuclear Information System (INIS)

    Huang Fuduan; Yu Degui; Lu Jingju; Ding Dejun; Zhao Yukun

    1991-02-01

    To use preoxidation condition with low concentration NP (nitric acid permanganate) instead of conventional high concentration AP (alkline permanganate ) for PWR oxidation decontamination (POD) was summarized. Experiments including three parts have been performed. The defilming performance and decontamination factor of preoxidation with low concentration NP, which is 100, 10 times lower than that of AP are better than that with high concentration AP. The reason has been studied with the aid of prefilmed specimens of corrosion potential measuring in NP solution and chromium release in NP and AP solutions. The behaviour of alloy 13 prefilmed specimen in NP preoxidation solution is different from 18-8 ss and Incoloy 800. In the low acidity, the corrosion potential moves toward positive direction as the acidity becomes high

  13. Dry decontamination for tritiated wastes

    International Nuclear Information System (INIS)

    Shi Zhengkun; Wu Tao; Dan Guiping; Xie Yun

    2009-01-01

    To aim at decontamination of tritiated wastes, we have developed and fabricated a dry tritium decontamination system, which is designed to reduce tritium surface contamination of various alloy by UV, ozone and heating. The result indicates that the elevation of temperature can obviously improve decontamination effect. With 3 h irradiation by 365 nm UV at 220 degree C, it has a decontamination rate of 99% to stainless steel surface. Ozone can more obviously improve decontamination effect when metal was heated. Ozone has a decontamination effect beyond 95% to stainless steel, aluminum and brass at 220 degree C. Tritium surface concentration of metal has a little increase after decontamination. (authors)

  14. Remote methods for decontamination and decommissioning operations

    International Nuclear Information System (INIS)

    DeVore, J.R.

    1986-01-01

    Three methods for the decontamination and decommissioning of nuclear facilities are described along with operational experience associated with each method. Each method described in some way reduces radiation exposure to the operating personnel involved. Electrochemical decontamination of process tanks is described using an in-situ method. Descriptions of two processes, electropolishing and cerium redox decontamination, are listed. A method of essentially smokeless cutting of process piping using a plasma-arc cutting torch is described. In one technique, piping is cut remotely from a distance using a specially modified torch holder. In another technique, cutting is done with master-slave manipulators inside a hot cell. Finally, a method for remote cutting and scarification of contaminated concrete is described. This system, which utilizes high-pressure water jets, is coupled to a cutting head or rotating scarification head. The system is suited for cutting contaminated concrete for removal or removing a thin layer in a controlled manner for decontamination

  15. PWR decontamination feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Silliman, P.L.

    1978-12-18

    The decontamination work which has been accomplished is reviewed and it is concluded that it is worthwhile to investigate further four methods for decontamination for future demonstration. These are: dilute chemical; single stage strong chemical; redox processes; and redox/chemical in combination. Laboratory work is recommended to define the agents and processes for demonstration and to determine the effect of the solvents on PWR materials. The feasibility of Indian Point 1 for decontamination demonstrations is discussed, and it is shown that the system components of Indian Point 1 are well suited for use in demonstrations.

  16. Long lasting decontamination foam

    Science.gov (United States)

    Demmer, Ricky L.; Peterman, Dean R.; Tripp, Julia L.; Cooper, David C.; Wright, Karen E.

    2010-12-07

    Compositions and methods for decontaminating surfaces are disclosed. More specifically, compositions and methods for decontamination using a composition capable of generating a long lasting foam are disclosed. Compositions may include a surfactant and gelatin and have a pH of less than about 6. Such compositions may further include affinity-shifting chemicals. Methods may include decontaminating a contaminated surface with a composition or a foam that may include a surfactant and gelatin and have a pH of less than about 6.

  17. PWR decontamination feasibility study

    International Nuclear Information System (INIS)

    Silliman, P.L.

    1978-01-01

    The decontamination work which has been accomplished is reviewed and it is concluded that it is worthwhile to investigate further four methods for decontamination for future demonstration. These are: dilute chemical; single stage strong chemical; redox processes; and redox/chemical in combination. Laboratory work is recommended to define the agents and processes for demonstration and to determine the effect of the solvents on PWR materials. The feasibility of Indian Point 1 for decontamination demonstrations is discussed, and it is shown that the system components of Indian Point 1 are well suited for use in demonstrations

  18. Chemical Decontamination at Browns Ferry Unit 1

    International Nuclear Information System (INIS)

    Hartwig, Ed; Reid, Richard

    2003-01-01

    In May, 2002, the Tennessee Valley Authority's (TVA) Board of Directors approved the recovery and restart of Unit 1 at Browns Ferry Nuclear Station. As an initial step in the site characterization and restart feasibility review, a majority of the primary reactor circuit was chemically decontaminated. Close cooperation between TVA and vendor personnel resulted in project completion ahead of schedule with outstanding results. The final average decontamination factors were excellent, and the final dose rates were very low, with contact readings on most points between one and three mRem/hr. In addition to allowing TVA to do a complete and thorough job of determining the feasibility of the Unit 1 restart, the decontamination effort will greatly reduce personnel exposure during plant recovery, both whole body exposure to gamma radiation and airborne exposure during pipe replacement efforts. The implementation of lessons learned from previous decontamination work performed at Browns Ferry, as well as decontamination efforts at other plants aided greatly in the success. Specific items of note are: (1) The initial leak check of the temporary decontamination system should include ancillary systems such as the spent resin system, as well as the main circulation loop. This could save time and dose exposure if leaks are discovered before the use of such systems is required. (2) Due to the quick turnaround time from the award of contract, a vendor representative was onsite early in the project to help with engineering efforts and procedures. This aided greatly in completing preparations for the decontamination. (3) The work was performed under a single maintenance activity. This resulted in great craft and plant support. (4) The constant coverage by the site's decontamination flush directors provided timely plant support and interface. (5) The FPC system isolation and back flushing to prevent residual chemicals from being left in the FPC system should have been addressed in more

  19. Development of strippable gel for surface decontamination applications

    International Nuclear Information System (INIS)

    Banerjee, D.; Sandhya, U.; Khot, S.A.; Srinivas, C.

    2015-07-01

    Strippable gels are an attractive option for decontamination of surfaces particularly when materials are to be reused after decontamination. The process in general results in good decontamination performance with minimal secondary waste generation. This paper reports on development of strippable gel formulation using polyvinyl alcohol as the gel former. Peeling behavior of the gel film improved when glycerol was used as plasticizer. Incorporation of decontaminating agents is essential for the gel to be effective, so a number of decontaminating agents were screened based on their miscibility with the gel, smooth peeling, and good decontamination performance. Based on this study, a strippable gel, ‘INDIGEL’ was formulated as a potential candidate for surface decontamination applications. Extensive trials on evaluation of decontamination performance of Indigel were done on simulated surfaces like stainless steel tray, stainless steel fume hood, PVC floor, granite and ceramic table tops. Results show that Indigel is highly effective for decontamination of surfaces contaminated with all types of radionuclides. Simplicity of its use coupled with good decontamination ability will find application in nuclear and other chemical industries. (author)

  20. Loop cleanup with redox decontamination technique

    International Nuclear Information System (INIS)

    Ren Xian Wen; Zhang Yuan

    1998-01-01

    The corrosion rate of stainless steel in nitric acid solution will be enhanced by existence of Ce 4+ . The goal of this study is to develop a circular decontamination process in medium of nitric acid, in order to use it in a loop clean up. That needs a specially designed electrolytic cell to oxidize the Ce 3+ into Ce 4+ . This regenerator's structure should be simple and easy to operate, and can meet the requirements of practical decontamination operation. The concentration of Ce 4+ in the nitric acid solution was selected to provide a suitable corrosion rate to contaminated stainless steel. The total concentration of cerium (III+IV) was also optimized to ensure that the regeneration rate of Ce 4+ could satisfy the consumption rate of Ce 4+ during decontaminating process. The operation parameters were selected strictly on the basis of our experimental results, so that the regeneration rate of Ce 4+ can be higher reasonably in proper operation conditions and not arise any problem related to safety of operation and nuclear aspects. It is considered that this decontamination process could be applied into either decommissioning or maintenance stage of nuclear facilities. The concentration of Ce 4+ and temperature are the main factors for corrosion rate, other factors should also be considered during decision of decontamination process. With the regenerator developed under contract No 7959/RB could obtain sufficient decontamination factors, when use following conditions: concentration of Ce 4+ is higher than 0.2 mol/1, the total concentration of cerium (III+IV) is higher than 0.4 mol/1, concentration of nitric acid is higher than 2 mol/1, temperature of decontamination operation is within 25 deg. C - 40 deg. C and temperature of regeneration is within 40 deg C - 50 deg.C

  1. Evaluation of a process for the decontamination of radioactive hotspots due to activated stellite particles

    International Nuclear Information System (INIS)

    Subramanian, V.; Chandramohan, P.; Srinivasan, M.P.; Rangarajan, S.; Velmurugan, S.; Narasimhan, S.V.; Khandelwal, R.C.

    2010-01-01

    Some of the Indian PHWRs which used stellite balls in the ball and screw mechanism of the adjustor rod drive mechanism in the moderator circuit encountered high radiation field in moderator system due to 60 Co. Release of particulate stellite was responsible for the hotspots besides the general uniform contamination of internal surfaces with 60 Co. Extensive laboratory studies have shown that it is possible to dissolve these stellite particles by adopting a three step redox process with permanganic acid as the oxidizing agent. These investigations with inactive stellite in powder form helped to optimize the process conditions. Permanganic acid was found to have the highest dissolution efficiency as compared to alkaline and nitric acid permanganate. The concentration of the permanganate was also found to be an important factor in deciding the efficiency of the dissolution of stellite. The efficiency of dissolution as a function of permanganic acid concentration showed a maximum. This process was evaluated for its effectiveness on components from nuclear power plants. Component decontamination was carried out on adjustor rod drive assemblies which had 60 Co activity due to stellite particles with the radiation field ranging from 3 R/h to 20 R/h. They were subjected to decontamination with permanganic acid as oxidizing agent, followed by citric acid and a solution containing EDTA, ascorbic acid and citric acid in 4:3:3 ratio by weight (EAC) as reducing formulations. A test rig was fabricated for this purpose. In the first trial, one adjustor rod drive mechanism was subjected to decontamination. After two cycles of treatment, an average decontamination factor (DF) of 6.8, with a maximum DF of 11.7 was achieved. The same process but one cycle was repeated on eight more adjustor rod drive mechanisms. 60 Co activity in the range of 13 - 93 mCi was removed from these adjustor rods. Loose contamination of the order of 30000 - 40000 dpm/cm 2 observed before decontamination

  2. Evaluation of a process for the decontamination of radioactive hotspots due to activated stellite particles

    Energy Technology Data Exchange (ETDEWEB)

    Subramanian, V.; Chandramohan, P.; Srinivasan, M.P.; Rangarajan, S.; Velmurugan, S.; Narasimhan, S.V., E-mail: svn@igcar.gov.in [BARC Facilities, Water and Steam Chemistry Div., Kalpakkam, Tamilnadu (India); Khandelwal, R.C. [Kakrapara Atomic Power Station, KAPS, Surat, Gujarat (India)

    2010-07-01

    Some of the Indian PHWRs which used stellite balls in the ball and screw mechanism of the adjustor rod drive mechanism in the moderator circuit encountered high radiation field in moderator system due to {sup 60}Co. Release of particulate stellite was responsible for the hotspots besides the general uniform contamination of internal surfaces with {sup 60}Co. Extensive laboratory studies have shown that it is possible to dissolve these stellite particles by adopting a three step redox process with permanganic acid as the oxidizing agent. These investigations with inactive stellite in powder form helped to optimize the process conditions. Permanganic acid was found to have the highest dissolution efficiency as compared to alkaline and nitric acid permanganate. The concentration of the permanganate was also found to be an important factor in deciding the efficiency of the dissolution of stellite. The efficiency of dissolution as a function of permanganic acid concentration showed a maximum. This process was evaluated for its effectiveness on components from nuclear power plants. Component decontamination was carried out on adjustor rod drive assemblies which had {sup 60}Co activity due to stellite particles with the radiation field ranging from 3 R/h to 20 R/h. They were subjected to decontamination with permanganic acid as oxidizing agent, followed by citric acid and a solution containing EDTA, ascorbic acid and citric acid in 4:3:3 ratio by weight (EAC) as reducing formulations. A test rig was fabricated for this purpose. In the first trial, one adjustor rod drive mechanism was subjected to decontamination. After two cycles of treatment, an average decontamination factor (DF) of 6.8, with a maximum DF of 11.7 was achieved. The same process but one cycle was repeated on eight more adjustor rod drive mechanisms. {sup 60}Co activity in the range of 13 - 93 mCi was removed from these adjustor rods. Loose contamination of the order of 30000 - 40000 dpm/cm{sup 2} observed

  3. Advance in radioactive decontamination

    International Nuclear Information System (INIS)

    Basteris M, J. A.; Farrera V, R.

    2010-09-01

    The objective of the present work was to determine if the application of the Na hypochlorite has some utility in the radioactive decontamination, in comparison with the water, detergent and alcohol. Several methods were compared for decontaminate the iodine 131 and technetium 99, the work table and the skin it was carried out an initial count with the Geiger Muller. Later on, in a single occasion, the areas were washed with abundant water, alcohol, clothes detergent and sodium hypochlorite (used commercially as domestic bleacher) without diluting. Observing that the percentage in the decrease of the counted radioactivity by the Geiger Muller, decreased in the following way: It was demonstrated that the Na hypochlorite presents the highest index of radioactive decontamination with 100% of effectiveness. The Na hypochlorite is an excellent substance that can be used with effectiveness and efficiency like decontamination element in the accident cases of radioactive contamination in the clinical laboratories of nuclear medicine. (Author)

  4. Concrete decontamination scoping tests

    International Nuclear Information System (INIS)

    Archibald, K.E.

    1995-01-01

    This report details the research efforts and scoping tests performed at the Idaho Chemical Process Plant using scabbling, chemical, and electro-osmotic decontamination techniques on radiologically contaminated concrete

  5. Some remarks about decontamination

    International Nuclear Information System (INIS)

    Bertini, A.

    1990-01-01

    Decontamination in itself is not the elimination of a problem, but corresponds to move that problem from one place to another. It is beneficial only if the contamination is less of a nuisance when moved to the ''other place''. Therefore any prospective decontamination process is to be considered essentially in terms of cost-benefit, and in particular in terms of reducing the burden on the waste management systems. The paper is not intended to deal with and to review critically the technical aspects of the various decontamination processes which are currently available. Its aim is to call the attention of those who may be faced with the problem of large-scale decontamination, so that this operation is carried out after all practical aspects have been examined. (author)

  6. Chemical decontamination: an overview

    International Nuclear Information System (INIS)

    Shaw, R.A.; Wood, C.J.

    1985-01-01

    The source of radioactive contamination in various types of power reactors is discussed. The methods of chemical decontamination vary with the manner in which the radioactive contaminants are deposited on the surface. Two types of dilute decontamination systems are available. One system uses organic acids and chelating agents, which are mildly reducing in nature. In this process, the oxide contaminants are removed by simple acidic dissolution and reductive dissolution. The second type of decontamination process is based on low oxidation state metal ions, which are more strongly reducing and do not require a corrosion inhibitor. All processes commercially available for decontamination of power reactors are not detailed here, but a few key issues to be considered in the selection of a process are highlighted. 2 figures, 2 tables

  7. Food decontamination using nanomaterials

    Science.gov (United States)

    The research indicates that nanomaterials including nanoemulsions are promising decontamination media for the reduction of food contaminating pathogens. The inhibitory effect of nanoparticles for pathogens could be due to deactivate cellular enzymes and DNA; disrupting of membrane permeability; and/...

  8. A remotely operated robot for decontamination tasks

    International Nuclear Information System (INIS)

    Dudar, A.M.; Vandewalle, R.C.

    1994-01-01

    Engineers in the Robotics Development Group at the Westinghouse Savannah River Company (WSRC) have developed a robot which will be used to decontaminate a pipe gallery of a tank farm used for nuclear waste storage. Personnel access is required into this pipe gallery to inspect existing pipes and perform repairs to secondary containment walls around the tank farm. Presently, the pipe gallery is littered with debris of various sizes and its surface is contaminated with activity levels up to 2.5E6 DPM (disintegrations per minute) alpha and exposure levels as high as 20 Rad/hr. Cleaning up this pipe gallery win be the mission of an all-hydraulic robotic vehicle developed in-house at WSRC caged the ''Remote Decon'' robot. The Remote Decon is a tracked vehicle which utilizes skid steering and features a six-degree-of-freedom (DOF) manipulator arm, a five-DOF front end loader type bucket with a rotating brush for scrubbing and decontaminating surfaces, and a three-DOF pan/tilt mechanism with cameras and lights. The Remote Decon system is connected to a control console via a 200 foot tethered cable. The control console was designed with ergonomics and simplicity as the main design factors and features three joysticks, video monitors, LED panels, and audible alarms

  9. Decommissioning and Decontamination

    International Nuclear Information System (INIS)

    Massaut, V.

    2000-01-01

    The objectives of SCK-CEN's decommissioning and decontamination programme are (1) to develop, test and optimise the technologies and procedures for decommissioning and decontamination of nuclear installations in order to minimise the waste arising and the distributed dose; (2) to optimise the environmental impact; (3) to reduce the cost of the end-of-life of the installation; (4) to make these new techniques available to the industry; (5) to share skills and competences. The programme and achievements in 1999 are summarised

  10. Facility decontamination technology workshop

    International Nuclear Information System (INIS)

    1980-10-01

    Purpose of the meeting was to provide a record of experience at nuclear facilities, other than TMI-2, of events and incidents which have required decontamination and dose reduction activities, and to furnish GPU and others involved in the TMI-2 cleanup with the results of that decontamination and dose reduction technology. Separate abstracts were prepared for 24 of the 25 papers; the remaining paper had been previously abstracted

  11. Special zone territory decontamination

    International Nuclear Information System (INIS)

    Samojlenko, Yu.N.; Golubev, V.V.

    1989-01-01

    Special zone is the Chernobyl' NPP operating site (OS). OS decontamination is described including reactor ruins from the accident moment. The process was begun from reactor bombardment with absorbing and filtering materials (sand, clay, lead, boron compounds). Then were produced soil shovelling, territory filling by dry concrete and laying concrete layer with thickness up to 300 mm. NPP room and equipment decontamination is described. 3 figs.; 3 tabs

  12. Facility decontamination technology workshop

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-10-01

    Purpose of the meeting was to provide a record of experience at nuclear facilities, other than TMI-2, of events and incidents which have required decontamination and dose reduction activities, and to furnish GPU and others involved in the TMI-2 cleanup with the results of that decontamination and dose reduction technology. Separate abstracts were prepared for 24 of the 25 papers; the remaining paper had been previously abstracted. (DLC)

  13. Development of filtration equipment to reuse PFC decontamination wastewater

    International Nuclear Information System (INIS)

    Kim, Gye Nam; Lee, Sung Yeol; Won, Hui Jun; Jung Chong Hun; Oh, Won Zin; Park, Jin Ho

    2005-01-01

    When PFC(Perfluorocarbonate) decontamination technology is applied to removal of radioactive contaminated particulate adhered at surface during the operation of nuclear research facilities, it is necessary to develop a filtration equipment to reuse of PFC solution due to high price, also to minimize the volume of second wastewater. Contaminated characteristics of hot particulate was investigated and a filtration process was presented to remove suspended radioactive particulate from PFC decontamination wastewater generated on PFC decontamination

  14. The efficiency analysis methods of decontamination of Fukushima Prefecture territory (Japan

    Directory of Open Access Journals (Sweden)

    Dmitriy V. Aron

    2017-01-01

    Full Text Available The article deals with the problems of radiological and economic efficiency of decontamination procedures as a measure of eliminating radioactive contamination in scarcely populated residential areas of Fukushima Prefecture (Japan.The objective of the research was to identify and compare with officially declared results the real effects of the decontamination measures on improving the radiation situation and reducing radiation doses for the population in Fukushima region. There was another objective of estimating the expected decontamination expenditure for these territories and the economic efficiency of this measure in accordance with the official international recommendations. The results of such kind of survey for Japan and actual values of the prevented doses due to the decontamination have not been published before. The key objective of this research was to assess the need for decontamination in sparsely populated areas of Fukushima Prefecture taking into account relatively low radiation background in these areas and significant associated financial losses.The initial data for the research have been taken from the Environment Ministry (Japan reports on the restoration progress in the NPP area. The data on the current radiation situation in Japan have been taken from the Japan Nuclear Regulatory Commission Internet publications. A mathematical modeling of the radiation situation in remediation territories near Fukushima-1 NPP was carried out in the research taking into account the simultaneous impact of several natural and anthropogenic factors. This mathematical model is described in the article. Some empirical dependencies obtained after the Chernobyl accident were also used in it.As the results of the research, the estimated values of actual, predicted and prevented by the decontamination and the resettlement measures doses to residents in one specific Fukushima prefecture municipality were presented.The total and average financial costs

  15. Coolant system decontamination

    International Nuclear Information System (INIS)

    Anstine, L.D.; James, D.B.; Melaika, E.A.; Peterson, J.P.

    1981-01-01

    An improved method for decontaminating the coolant system of water cooled nuclear power reactors and for regenerating the decontamination solution is described. A small amount of one or more weak-acid organic complexing agents is added to the reactor coolant, and the pH is adjusted to form a decontamination solution which is circulated throughout the coolant system to dissolve metal oxides from the interior surfaces and complex the resulting metal ions and radionuclide ions. The coolant containing the complexed metal ions and radionuclide ions is passed through a strong-base anion exchange resin bed which has been presaturated with a solution containing the complexing agents in the same ratio and having the same pH as the decontamination solution. As the decontamination solution passes through the resin bed, metal-complexed anions are exchanged for the metal-ion-free anions on the bed, while metal-ion-free anions in the solution pass through the bed, thus removing the metal ions and regenerating the decontamination solution. (author)

  16. Testing of a portable ultrahigh pressure water decontamination system (UHPWDS)

    International Nuclear Information System (INIS)

    Lovell, A.; Dahlby, J.

    1996-02-01

    This report describes the tests done with a portable ultrahigh pressure water decontamination system (UHPWDS) on highly radioactively contaminated surfaces. A small unit was purchased, modified, and used for in-situ decontamination to change the waste level of the contaminated box from transuranic (TRU) waste to low- level waste (LLW). Low-level waste is less costly by as much as a factor of five or more if compared with TRU waste when handling, storage, and disposal are considered. The portable unit we tested is commercially available and requires minimal utilities for operation. We describe the UHPWDS unit itself, a procedure for its use, the results of the testing we did, and conclusions including positive and negative aspects of the UHPWDS

  17. Decontamination of medical radioisotopes from hard surfaces using peelable polymer-based decontamination agents

    International Nuclear Information System (INIS)

    Draine, Amanda E.; Walter, Ken J.; Johnson, Thomas E.

    2008-01-01

    Full text: Medical radioisotopes used to treat and diagnose patients often contaminate surfaces in patient treatment rooms. They are typically short-lived and decay within a matter of days or weeks. However, down time in a medical facility related to radioisotope contamination is costly and can impact patient care. Most liquid or solid spills can be contained and disposed in radioactive wastes fairly completely and quickly; however residual contamination may remain on the contacted surface. Although liquid decontamination agents can be used to address the issue of residual contamination, they often require multiple applications with attendant scrubbing and wiping. Liquid decontamination can also produce large volumes of low-level radioactive waste. To look at reducing radioactive waste volumes, research was conducted on the efficacy of three low-volume peel able decontamination agents. Testing was performed on hard surfaces, such as vinyl composition floor tiles and stainless steel, which are found in many hospitals, research laboratories, and universities. The tiles were contaminated with the medical use isotopes of 99m Tc, Tl-201, and I-131 and subsequently decontaminated with one of the three decontamination agents. Quantitative and qualitative data were obtained for each of three different peel able decontamination agent formulations. Quantitative data included environmental temperature and relative humidity, application thickness, dry time, contact time, and decontamination efficacy of the agents on the tested surfaces. Qualitative factors included ease of application and pee lability, as well as sag resistance and odor of each agent. Initial studies showed that under standard conditions there were reproducible differences in the decontamination efficacies among the three different decontamination formulations. (author)

  18. Decontaminating soil organic pollutants with manufactured nanoparticles.

    Science.gov (United States)

    Li, Qi; Chen, Xijuan; Zhuang, Jie; Chen, Xin

    2016-06-01

    Organic pollutants in soils might threaten the environmental and human health. Manufactured nanoparticles are capable to reduce this risk efficiently due to their relatively large capacity of sorption and degradation of organic pollutants. Stability, mobility, and reactivity of nanoparticles are prerequisites for their efficacy in soil remediation. On the basis of a brief introduction of these issues, this review provides a comprehensive summary of the application and effectiveness of various types of manufactured nanoparticles for removing organic pollutants from soil. The main categories of nanoparticles include iron (oxides), titanium dioxide, carbonaceous, palladium, and amphiphilic polymeric nanoparticles. Their advantages (e.g., unique properties and high sorption capacity) and disadvantages (e.g., high cost and low recovery) for soil remediation are discussed with respect to the characteristics of organic pollutants. The factors that influence the decontamination effects, such as properties, surfactants, solution chemistry, and soil organic matter, are addressed.

  19. Lessons Learned from Decontamination Experiences

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, JH

    2000-11-16

    This interim report describes a DOE project currently underway to establish what is known about decontamination of buildings and people and the procedures and protocols used to determine when and how people or buildings are considered ''clean'' following decontamination. To fulfill this objective, the study systematically examined reported decontamination experiences to determine what procedures and protocols are currently employed for decontamination, the timeframe involved to initiate and complete the decontamination process, how the contaminants were identified, the problems encountered during the decontamination process, how response efforts of agencies were coordinated, and the perceived social psychological effects on people who were decontaminated or who participated in the decontamination process. Findings and recommendations from the study are intended to aid decision-making and to improve the basis for determining appropriate decontamination protocols for recovery planners and policy makers for responding to chemical and biological events.

  20. Evaluation of zeolite mixtures for decontaminating high-activity-level water at the Three Mile Island Unit 2 Nuclear Power Station

    International Nuclear Information System (INIS)

    Collins, E.D.; Campbell, D.O.; King, L.J.; Knauer, J.B.; Wallace, R.M.

    1984-05-01

    Mixtures of Linde Ionsiv IE-96 and Ionsiv A-51 were evaluated for use in the Submerged Demineralizer System (SDS) that was installed at the Three Mile Island Unit 2 Nuclear Power Station to decontaminate approx. 2780 m 3 of high-activity-level water. The original SDS flowsheet was conservatively designed for removal of cesium and strontium and would have required the use of approx. 60 SDS columns. Mixed zeolite tests were made on a 10 -5 scale and indicated that the appropriate ratio of IE-96/A-51 was 3/2. A mathematical model was used to predict the performance of the mixed zeolite columns in the SDS configuration and with the intended method of operation. Actual loading results were similar to those predicted for strontium and better than those predicted for cesium. The number of SDS columns needed to process the HALW was reduced to approx. 10. 6 references, 4 figures, 2 tables

  1. Decontamination and winter conditions

    International Nuclear Information System (INIS)

    Quenild, C.; Tveten, U.

    1984-12-01

    The report deals with two decontamonation experiments under winter conditions. A snow-covered parking lot was contaminated, and the snow was subsequently removed using standard snow-moving equipment. The snow left behind was collected and the content of contaminant was determined. A non-radioactive contaminant was used. A decontamination factor exceeding 100 was obtained. Although the eksperimental conditions were close to ideal, it is reason to believe that extremely efficient removal of deposited materials on a snow surface is achivable. In another investigation, run-off from agricultural surface, contaminated while covered with snow, was measured A lycimeter was used in this experiment. A stable layer of ice and snow was allowed to form before contamination. The run-off water was collected at each thaw period until all snow and ice was gone. Cs-134 was used as contaminant. Roughly 30% of the Cs-134 with which the area was contaminated ran off with the melt water. Following a reactor accident situation, this would have given a corresponding reduction in the long term doses. Both of these experiments show that consequence calculation assumptions, as they are currently applied to large accident assessment, tend to overestimate the consequences resulting from accidents taking place under winter conditions

  2. Decontamination technology assessment

    International Nuclear Information System (INIS)

    Allen, R.P.; Konzek, G.J.; Schneider, K.J.; Smith, R.I.

    1988-01-01

    This study was conducted by the Pacific Northwest Laboratory (PNL) for the U.S. Department of Energy (DOE) to identify and technically assess foreign decontamination and decommissioning (D and D) technology developments that may represent significant improvements over D and D technology currently available or under development in the United States. Technology need areas for nuclear power reactor decommissioning operations were identified and prioritized using the results of past light water rector (LWR) decommissioning studies to quantitatively evaluate the potential for reducing cost and decommissioning worker radiation dose for each major decommissioning activity. Based on these identified needs, current foreign D and D technologies of potential interest to the U.S. were identified through personal contacts and the collection and review of an extensive body of D and D literature. These technologies were then assessed qualitatively to evaluate their uniqueness, potential for a significant reduction in D and D costs and/or worker radiation dose, development status, and other factors affecting their value and applicability to U.S. needs

  3. Chemical decontamination and melt densification

    International Nuclear Information System (INIS)

    Dillon, R.L.; Griggs, B.; Kemper, R.S.; Nelson, R.G.

    1976-01-01

    Preliminary studies on the chemical decontamination and densification of Zircaloy, stainless steel, and Inconel undissolved residues remaining after dissolution of the UO 2 --PuO 2 spent fuel material from sheared fuel bundles are reported. The studies were made on cold or very small samples to demonstrate the feasibility of the processes developed before proceeding to hot cell demonstrations with kg level of the sources. A promising aqueous decontamination method for Zr alloy cladding was developed in which oxidized surfaces are conditioned with HF prior to leaching with ammonium oxalate, ammonium citrate, ammonium fluoride, and hydrogen peroxide. Feasibility of molten salt decontamination of oxidized Zircaloy was demonstrated. A low melting alloy of Zircaloy, stainless steel, and Inconel was obtained in induction heated graphite crucibles. Segregated Zircaloy cladding sections were directly melted by the inductoslag process to yield a metal ingot suitable for storage. Both Zircaloy and Zircaloy--stainless steel--Inconel alloys proved to be highly satisfactory getters and sinks for recovered tritium

  4. New techniques available for decontamination

    International Nuclear Information System (INIS)

    Costes, J.R.; Cochaux, C.

    1996-01-01

    As nuclear industry dismantling operations become more widespread, one naturally sees the growth of specific needs in decontamination techniques. In this paper, the authors present two applications involving the decategorization of wastes from dismantling. Decategorization means using decontamination to transform the wastes into a lower, and thus cheaper, category. The first application is in decategorizing large mild steel pipes, which come from the stage decommissioning of the G2/G3 graphite gas reactors at Marcoule. A large number of these pipes (4000 t) have been contaminated by deposits and encrustations of 60 Co (95%) and 137 Cs (5%) to the extent of 200 Bq/cm 2 . The objective was to avoid having to store them on surface sites for 300 yr. This is achieved by decontaminating them to a level that enables the metal to be reused. The other application involves stainless steel waste cut into small sections, which comes from the stage decommissioning of a radiometallurgy laboratory (RM2) at Fontenay aux Roses. This waste was not acceptable to the surface storage center due to high levels of alpha contamination. A decategorization technique has been developed for part of the 13 tonnes of waste concerned, which avoids the need for it to be disposed of in extremely costly geologic repositories

  5. Development of novel high power-short time (HPST) microwave assisted commercial decontamination process for dried turmeric powder (Curcuma Longa L.).

    Science.gov (United States)

    Behera, G; Sutar, P P; Aditya, S

    2017-11-01

    The commercially available dry turmeric powder at 10.34% d.b. moisture content was decontaminated using microwaves at high power density for short time. To avoid the loss of moisture from turmeric due to high microwave power, the drying kinetics were modelled and considered during optimization of microwave decontamination process. The effect of microwave power density (10, 33.5 and 57 W g -1 ), exposure time (10, 20 and 30 s) and thickness of turmeric layer (1, 2 and 3 mm) on total plate, total yeast and mold (YMC) counts, color change (∆E), average final temperature of the product (T af ), water activity (a w ), Page model rate constant (k) and total moisture loss (ML) was studied. The perturbation analysis was carried out for all variables. It was found that to achieve more than one log reduction in yeast and mold count, a substantial reduction in moisture content takes place leading to the reduced output. The microwave power density significantly affected the YMC, T af and a w of turmeric powder. But the thickness of sample and microwave exposure time showed effect only on T af , a w and ML. The colour of turmeric and Page model rate constant were not significantly changed during the process as anticipated. The numerical optimization was done at 57.00 W g -1 power density, 1.64 mm thickness of sample layer and 30 s exposure time. It resulted into 1.6 × 10 7 CFU g -1 YMC, 82.71 °C T af , 0.383 a w and 8.41% (d.b.) final moisture content.

  6. Decontamination tests on tritium-contaminated materials

    International Nuclear Information System (INIS)

    Boutot, P.; Schipfer, P.

    1967-01-01

    These tests are designed to try out various processes liable to be applied to the decontamination of a material contaminated with tritium. The samples are thin stainless- steel slabs contaminated in the laboratory with elements extracted from industrial installations. The measurement of the initial and residual activities is carried out using an open-window BERTHOLD counter. The best results are obtained by passing a current of pre-heated (300 deg. C) air containing water vapour. This process makes it possible to reach a decontamination factor of 99.5 per cent in 4 hours. In a vacuum, the operation has to be prolonged to 100 hours in order to obtain a decontamination factor of 99.2 per cent. Wet-chemical or electrolytic treatments are efficient but their use is limited by the inherent corrosion risks. A study of the reappearance of the contamination has made it possible to observe that this phenomenon occurs whatever the process used. (authors) [fr

  7. Mechanical decontamination techniques for floor drain systems

    International Nuclear Information System (INIS)

    Palau, G.L.

    1987-01-01

    The unprecedented nature of cleanup activities at Three Mile Island Unit 2 (TMI-2) following the 1979 accident has necessitated the development of new techniques to deal with radiation and contamination in the plant. One of these problems was decontamination of floor drain systems, which had become highly contaminated with various forms of dirt and sludge containing high levels of fission products and fuel from the damaged reactor core. The bulk of this contamination is loosely adherent to the drain pipe walls; however, significant amounts of contamination have become incorporated into pipe wall oxide and corrosion layers and embedded in microscopic pits and fissures in the pipe wall material. The need to remove this contamination was recognized early in the TMI-2 cleanup effort. A program consisting of development and laboratory testing of floor drain decontamination techniques was undertaken early in the cleanup with support from the Electric Power Research Institute (EPRI). Based on this initial research, two techniques were judged to show promise for use at TMI-2: a rotating brush hone system and a high-pressure water mole nozzle system. Actual use of these devices to clean floor drains at TMI-2 has yielded mixed decontamination results. The decontamination effectiveness that has been obtained is highly dependent on the nature of the contamination in the drain pipe and the combination of decontamination techniques used

  8. Results from the preliminary conveyor evaluation of the high-energy beta scintillation sensor at the Fernald Soil Decontamination Pilot Plant

    International Nuclear Information System (INIS)

    Schilk, A.J.; Knopf, M.A.

    1994-07-01

    W tested a high-energy beta scintillation sensor to evaluate its efficacy in continually characterizing washed soils moving on a conveyor belt at Fernald's Soil Decontamination Pilot Plant (SDPP). This sensor was originally developed for monitoring uranium-contaminated soils in the field. It has a multi-layer design that enables it to discriminate against lower-energy beta particles from natural sources. It can also distinguish, to some extent, gamma rays and cosmic-induced species. The sensor detects uranium activity indirectly, based on the assumption that secular equilibrium exists between the targeted radionuclide ( 234m Pa) and its parent ( 238 U). Several 1-h background counts were made at the SDPP each day of the evaluation period. The average background count rate was found to be comparable to that observed under previous laboratory conditions. Static runs were performed on soils from SDPP test runs No. 1 and No. 17 to determine the extent of any residual activity following the decontamination process. Soils were found to contain 158±30 pCi/g and 114±25 pCi/g of 234 Th- 234m Pa ( 238 U?), respectively. But the soils had considerable moisture, and concern existed that this moisture would act as an additional beta attenuator and thereby give results that were erroneously low. Therefore, a soil sample was baked overnight, and the hard-baked clay that resulted was ground into small fragments and counted. This sample was counted for 30 min as before, and the total activity was determined to be 313±44 pCi/g of 234 Th 234m Pa ( 238 U?). Based on the test No. 1 results, a dry-to-wet activity ratio of 1.98 has been established. Hence, if the moisture content of test No. 17 was equivalent to that of test No. 1, the actual 234 Th- 234m Pa ( 238 U?) activity level is expected to be approximately 226 pCi/g

  9. Decontamination Strategy for Large Area and/or Equipment Contaminated with Chemical and Biological Agents using a High Energy Arc Lamp (HEAL)

    Energy Technology Data Exchange (ETDEWEB)

    Schoske, Richard [ORNL; Kennedy, Patrick [ORNL; Duty, Chad E [ORNL; Smith, Rob R [ORNL; Huxford, Theodore J [ORNL; Bonavita, Angelo M [ORNL; Engleman, Greg [ORNL; Vass, Arpad Alexander [ORNL; Griest, Wayne H [ORNL; Ilgner, Ralph H [ORNL; Brown, Gilbert M [ORNL

    2009-04-01

    A strategy for the decontamination of large areas and or equipment contaminated with Biological Warfare Agents (BWAs) and Chemical Warfare Agents (CWAs) was demonstrated using a High Energy Arc Lamp (HEAL) photolysis system. This strategy offers an alternative that is potentially quicker, less hazardous, generates far less waste, and is easier to deploy than those currently fielded by the Department of Defense (DoD). For example, for large frame aircraft the United States Air Force still relies on the combination of weathering (stand alone in environment), air washing (fly aircraft) and finally washing the aircraft with Hot Soapy Water (HSW) in an attempt to remove any remaining contamination. This method is laborious, time consuming (upwards of 12+ hours not including decontamination site preparation), and requires large amounts of water (e.g., 1,600+ gallons for a single large frame aircraft), and generates large amounts of hazardous waste requiring disposal. The efficacy of the HEAL system was demonstrated using diisopropyl methyl phosphonate (DIMP) a G series CWA simulant, and Bacillus globigii (BG) a simulant of Bacillus anthracis. Experiments were designed to simulate the energy flux of a field deployable lamp system that could stand-off 17 meters from a 12m2 target area and uniformly expose a surface at 1360 W/m2. The HEAL system in the absence of a catalyst reduced the amount of B. globigii by five orders of magnitude at a starting concentration of 1.63 x 107 spores. In the case of CWA simulants, the HEAL system in the presence of the catalyst TiO2 effectively degraded DIMP sprayed onto a 100mm diameter Petri dish in 5 minutes.

  10. Solving decontaminable flooring problems

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    Pennsylvania Power and Light wanted to cover deteriorating concrete in unit 2 of its Susquehanna BWR with a smooth, durable, decontaminable coating. Traditionally, floors in the plant had been coated with epoxy paint, but many of these floors suffered delamination, and failed in three to five years. Painting with epoxy would also interrupt operations for as much as three days while the floor dried, yet critical instruments in some areas had to be monitored at least once per shift. In addition, conventional floor surface preparation produced dust and vibration around sensitive equipment. The solution was a dustless scabbling system for surface preparation, followed by the installation of a high-strength acrylic industrial floor known as Silakal. The work was carried out by Pentek. Silikal bonds to the underlying concrete, so that delamination of the floor will not occur even under severe traffic conditions. Another advantage of this type of flooring is that it cures in one hour, so floor resurfacing has only minimal impact on plant operations. (author)

  11. Gentilly 1: decontamination program

    International Nuclear Information System (INIS)

    Le, H.; Denault, P.

    1985-01-01

    The Gentilly 1 station, a 250-MW(e) light-water-cooled and heavy-water-moderated nuclear reactor, is being decommissioned to a static state (variant of stage 1) condition by Atomic Energy of Canada Limited (AECL). The scope of the decontamination program at the Gentilly 1 site includes the fuel pool and associated systems, the decontamination center, the laundry, the feedwater pumps and piping systems, the service building ventilation and drainage systems, and miscellaneous floor and wall areas. After an extensive literature review for acceptable decontamination methods, it was decided that the decontamination equipment used at Gentilly 1 during the program would include a hydrolaser, a scarifier, chipping hammers, a steam cleaner, an ultrasonic bath, and cutting tools. In addition, various foams, acids, detergents, surfactants, and abrasives are used alone and in tandem with the above equipment. This paper highlights the result of these decontaminations, their effectiveness, and the recommendation for future application. The methodology in performing these operations are also presented

  12. Research and development activities of the Institut fuer Nukleare Entsorgungstechnik on the decontamination of surfaces

    International Nuclear Information System (INIS)

    Dippel, T.; Hentschel, D.; Kunze, S.

    1983-06-01

    After developing a procedure for the ''Testing of Surface Coating Materials for the Decontamination'' about 900 different surface coating materials had been tested and evaluated for the domestic and foreign industry. The results prove the following basic facts: Surface coatings, low in porosity, forming a smooth surface and containing limited amounts of filler are in the majority very effectively decontaminated if they are prepared of chemically stable, water repellent materials; Decontamination results are drastically poorer if the degree of filling of the materials is high especially if hygroscopic fillers and/or hygroscopic colouring matters are used. Currently available cleansers and washing powders used for decontamination did not fulfill the three basic demands for a decontamination agent: high efficiency, small foam generation and sufficient thermal stability. Therefore for the decontamination of walls, floors, etc. a water delutable, liquid cleanser was developed. In the same context a washing powder was optimized for the decontamination of contaminated clothing. The experiments on the decontamination of stainless steels ended up with the formulation of a pickling paste. Furthermore all investigations were aimed at a minimization of the waste generation by the decontamination process. This resulted in decontamination techniques, in which the decontaminating agents were applied in thin layers. A comparison of the currently practiced dipping technique with the coating technique showed that the latter one gave the better decontamination results and that the amount of decontamination waste was reduced. (orig./HP) [de

  13. TMI-2 containment decontamination plans

    International Nuclear Information System (INIS)

    McDougall, F.

    1980-01-01

    Because of other priorities such as reentry, purging, and recovery, containment decontamination is only in the preliminary planning stages. This paper summarizes the study with emphasis on the remote decontamination techniques

  14. Decontamination of 125I in Medical Laboratory

    International Nuclear Information System (INIS)

    Abdel Geleel, M.; Tawfeek, A.A.

    2009-01-01

    A radiological laboratory for diagnoses was contaminated by 125 I. A large-scale survey of gamma-radiation has been made in different locations of the floors and walls of the lab to determine the contaminated area and its activity. The activity level before decontamination for the wall and floor was 1400 and 2000 Bq/cm 2 respectively. Decontamination was carried out by using ethyl alcohol, potassium permanganate, ethylene diamine tetracetic acid and tissue papers. Decontamination factor has been calculated and it was 175 and 200 for the wall and floor respectively. D and D computer code has been used to calculate Total Effective Dose Equivalent (TEDE). TEDE from the wall and floor before decontamination were 3.05 and 4.35 ( mSv/yr ) while after decontamination were 18 and 23μSv/yr respectively. These results are lower than the Egyptian and the international regulations (10 mSv/y for the public ) according to International Atomic Energy agency, IAEA, Safety Series, SS, no. 115 (1994).

  15. Radioactive decontamination of equipment

    International Nuclear Information System (INIS)

    1982-03-01

    After a recall of some definitions relating to decontamination techniques and of the regulation into effect, the principles to be respected to arrange rationally work zones are quoted while insisting more particularly on the types of coatings which facilitate maintenance operations and the dismantling of these installations. Then, the processes and equipments to use in decontamination units for routine or particular operations are described; the list of recommended chemical products to decontaminate the equipment is given. The influence of these treatments on the state and the duration of life of equipments is studied, and some perfectible methods are quoted. In the appendix, are given: the limits of surface contamination accepted in the centers; a standard project which defines the criteria of admissible residual contamination in wastes considered as cold wastes; some remarks on the interest that certain special ventilation and air curtain devices for the protection of operators working on apparatus generating contaminated dusts [fr

  16. Analysis on the Current Status of Chemical Decontamination Technology of Steam Generators in the Oversea Nuclear Power Plants (NPPs)

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Taebin; Kim, Sukhoon; Kim, Juyoul; Kim, Juyub; Lee, Seunghee [FNC Technology Co. Ltd., Yongin (Korea, Republic of)

    2015-10-15

    The steam generators in Hanbit Unit 3 and 4 are scheduled to be replaced in 2018 and 2019, respectively. Nevertheless, the wastes from the dismantled steam generators are currently just on-site stored in the NPP because there are no disposal measures for the waste and lack of the decontamination techniques for large-sized metallic equipment. In contrast, in the oversea NPPs, there are many practical cases of chemical decontamination not only for oversized components in the NPPs such as reactor pressure vessel and steam generator, but also for major pipes. Chemical decontamination technique is more effective in decontaminating the components with complicated shape compared with mechanical one. Moreover, a high decontamination factor can be obtained by using strong solvent, and thereby most of radionuclides can be removed. Due to these advantages, the chemical decontamination has been used most frequently for operation of decontaminating the large-sized equipment. In this study, an analysis on the current status of chemical decontamination technique used for the steam generators of the foreign commercial NPPs was performed. In this study, the three major chemical decontamination processes were reviewed, which are applied to the decommissioning process of the steam generators in the commercial NPPs of the United States, Germany, and Belgium. The three processes have the different features in aspect of solvent, while those are based in common on the oxidation and reduction between the target metal surface and solvents. In addition, they have the same goals for improving the decontamination efficiency and decreasing the amount of the secondary waste generation. Based on the analysis results on component sub-processes and major advantages and disadvantages of each process, Table 2 shows the key fundamental technologies for decontamination of the steam generator in Korea and the major considerations in the development process of each technology. It is necessary to prepare

  17. Electrokinetic decontamination of concrete

    Energy Technology Data Exchange (ETDEWEB)

    Lomasney, H. [ISOTRON Corp., New Orleans, LA (United States)

    1995-10-01

    The U.S. Department of Energy has assigned a priority to the advancement of technology for decontaminating concrete surfaces which have become contaminated with radionuclides, heavy metals, and toxic organics. This agency is responsible for decontamination and decommissioning of thousands of buildings. Electrokinetic extraction is one of the several innovative technologies which emerged in response to this initiative. This technique utilizes an electropotential gradient and the subsequent electrical transport mechanism to cause the controlled movement of ionics species, whereby the contaminants exit the recesses deep within the concrete. This report discusses the technology and use at the Oak Ridge k-25 plant.

  18. Radiation decontamination of spices

    International Nuclear Information System (INIS)

    Jan, M.; Sattar, A.; Ahmad, W.A.; Khan, I.

    1990-06-01

    In this report radiation decontamination was initiated to investigate the red pepper, which is widely consumed in all parts of Pakistan. The samples were collected from local market and prepared for gamma radiation at dose level of 0, 2.5, 5.0, 7.5, and 10.0 kGy. The measurement of total fungal count was carried out immediately after irradiation and the at two months storage interval. It was reported that radiation dose 10.0 kGy is suitable for complete decontamination of red pepper. (A.B.)

  19. Modeling for pipe decontamination by means of high-frequency percussive action; Modellerstellung fuer die Rohrdekontamination mittels hochfrequenter Schlagwirkung

    Energy Technology Data Exchange (ETDEWEB)

    Aminy, Akramullah

    2014-07-30

    The formation of persistent scales in pipes causes lower flow rates and therefore represents an economic problem. The contamination of scales - which usually is the case in most industrial applications - also poses a problem with respect to the scales' environmental compatibility. The currently applied techniques for the removal of these scales involve the use of auxiliary materials which accumulate large quantities of secondary waste that is costly to be disposed of. In this research, an environmentally friendly removal method for tubing scales was developed and qualified. The analysis of the currently used technologies formed the basis for the analysis and systematic evaluation of different principles of removal action methods. Consequently, a concept for a new impact based removal method was established. The mechanism of this technique is the application of a high-frequency percussive action by a geometrically defined tool. The impact on the scales cracks their surface and causes their fracture and thus the detachment from the pipes. Compared to alternative removal methods this proposed technique works without any auxiliary material and thus prevents the production of secondary waste. The investigation of the impact process was carried out in a newly developed test rig. In this test rig, the maximum forces of the percussive tool were measured with shear force sensors on the tubing surface and the resulting stress on the tube was obtained. The evaluation of the measured values using the method of descriptive statistics demonstrated that the high dynamic stress of the tubing due to the complex tool motion is based on a normal distribution. Based on this evaluation, the effects of the influencing factors on the stress of the tubings were systematically measured and outlined in a mathematical model. This model describes the dependency of the tool and the process of related factors that influences the tubing stress. According to this model, this stress is

  20. Predicting ion exchange resins decontamination factors. Experiments on synthetic primary coolant containing Ni, Co and Ag and modeling results

    International Nuclear Information System (INIS)

    Bachet, Martin; Schneider, Hélène; Jauberty, Loïc; Windt, Laurent De; Dieuleveult, Caroline de; Tevissen, Etienne

    2014-01-01

    Experiments performed under chemical and flow conditions representative of pressurized water reactors (PWR) primary fluid purification by ion exchange resins (Amberlite IRN9882) are modeled with the OPTIPUR code, considering 1D reactive transport in the mixed-bed column with convective/dispersive transport between beads and electro-diffusive transport within the boundary film around the beads. The effectiveness of the purification in these dilute conditions is highly related to film mass transfer restrictions, which are accounted for by adjustment of a common mass transfer coefficient (MTC) on the experimental initial leakage or modeling of species diffusion through the bead film by the Nernst-Planck equation. A detailed analysis of the modeling against experimental data shows that the Nernst-Planck approach with no adjustable parameters performs as well as, or better, than the MTC approach, particularly to simulate the chromatographic elution of silver by nickel and the subsequent enrichment of the solution in the former metal. (author)

  1. Biodegradation of concrete intended for their decontamination

    International Nuclear Information System (INIS)

    Jestin, A.

    2005-05-01

    The decontamination of sub-structural materials represents a stake of high importance because of the high volume generated. It is agreed then to propose efficient and effective processes. The process of bio-decontamination of the hydraulic binders leans on the mechanisms of biodegradation of concretes, phenomenon characterized in the 40's by an indirect attack of the material by acids stem from the microbial metabolism: sulphuric acid (produced by Thiobacillus), nitric acid (produced by Nitrosomonas and Nitrobacter) and organic acids (produced by fungi). The principle of the bio-decontamination process is to apply those microorganisms on the surface of the contaminated material, in order to damage its surface and to retrieve the radionuclides. One of the multiple approaches of the process is the use of a bio-gel that makes possible the micro-organisms application. (author)

  2. Cadmium decontamination using in-house resin

    International Nuclear Information System (INIS)

    Pal, Sangita; Thalor, K.L; Prabhakar, S.; Srivastava, V.K.; Goswami, J.L.; Tewari, P.K.; Dhanpal, Pranav; Goswami, J.L.

    2010-01-01

    A selective and strong in-house chelator has been studied w.r.t. basic parameters like concentration, time, and elution. De-contamination of cadmium, mercury, chromium, lead etc by using high uptake values fro cadmium ions proves its selectivity with high elution ratio ensures further decontamination of run-off water during natural calamities. In three step cascade use the concentration of original cadmium solution (500 ppm) decocted to safe disposable attribute. This polymeric ligand exchanger displayed outlet effluent concentration to 1 ppm and less than 200 ppb when treated for inlet feed concentration of 50 ppm and 500 ppm respectively. (author)

  3. Magnetic separation for soil decontamination

    International Nuclear Information System (INIS)

    Avens, L.R.; Worl, L.A.; deAguero, K.J.; Padilla, D.D.; Prenger, F.C.; Stewart, W.F.; Hill, D.D.; Tolt, T.L.

    1993-01-01

    High gradient magnetic separation (HGMS) is a physical separation process that is used to extract magnetic particles from mixtures. The technology is used on a large scale in the kaolin clay industry to whiten or brighten kaolin clay and increase its value. Because all uranium and plutonium compounds are slightly magnetic, HGMS can be used to separate these contaminants from non-magnetic soils. A Cooperative Research and Development Agreement (CRADA) was signed in 1992 between Los Alamos National Laboratory (LANL) and Lockheed Environmental Systems and Technologies Company (LESAT) to develop HGMS for soil decontamination. This paper reports progress and describes the HGMS technology

  4. New decontamination processes for liquid effluents and solid materials

    International Nuclear Information System (INIS)

    Faure, S.

    2008-01-01

    New decontamination processes are being studied in order to protect workers and to reduce strongly the quantity of secondary wastes produced. 2 decontamination processes for liquid nuclear wastes are under studies. First, the coprecipitation process whose improvement is based on a better control of the 2 coupled mechanisms involved in the process: the formation of adsorbent particles and the uptake of radionuclides. Secondly, the column process whose development focuses on new materials that can be used to absorb cesium in a reversible way. 3 new decontamination processes for solid materials are being developed. First, processes using drying gels are under investigation in order to treat materials like lead, aluminium, iron and stainless steel. Real decontamination of hot cells by drying gel process has been performed and a decontamination factor between 16 and 25 has been obtained on stainless steels. Secondly, new foam decontamination processes have been developed, they are based on the use of new foams stabilized by biodegradable non-ionic surfactants: alkyl-poly-glucosides and viscofiers or nano-particles. The aim is to increase the foam lifetime. Thirdly, new surfactants in solution decontamination processes have been studied, the aim is to decontaminate through degreasing by using acidic surfactants. The idea is to combine emulsification and wetting power. (A.C.)

  5. Development and design application of cerium (IV) decontamination process

    International Nuclear Information System (INIS)

    Bray, L.A.; Seay, J.M.

    1988-01-01

    A simple and effective method was developed for decontamination of high-level waste canisters. This method of chemical decontamination is applicable to a wide variety of contaminated equipment found in the nuclear industry. Conceptual design of the cerium [Ce(IV)] decontamination process equipment has been completed for the West Valley Demonstration project (WVDP) vitrification facility. This remote equipment, which is the first engineering scale application of this technology, will remove surface contamination from stainless-steel (SS) containers containing high-level waste (HLW) glass prior to placing them into temporary storage and ultimate shipment to a U.S. Department of Energy (DOE) repository for disposal. The objective of the development and design study was to identify an effective chemical process and to design equipment to decontaminate the HLW glass canisters to limits that meet U.S. DOE requirements. The equipment includes canister-capping and smear stations in addition to the decontamination module and associated services

  6. Development and design application of cerium (IV) decontamination process

    International Nuclear Information System (INIS)

    Bray, L.A.; Seay, J.M.

    1988-10-01

    A simple and effective method was developed for decontamination of high-level waste canisters. This method of chemical decontamination is applicable to a wide variety of contaminated equipment found in the nuclear industry. Conceptual design of the cerium [Ce(IV)] decontamination process equipment has been completed for the West Valley Demonstration Project (WVDP) vitrification facility. This remote equipment, which is the first engineering scale application of this technology, will remove surface contamination from stainless-steel (SS) containers containing high-level waste (HLW) glass prior to placing them into temporary storage and ultimate shipment to a US Department of Energy (DOE) repository for disposal. The objective of the development and design study was to identify an effective chemical process and to design equipment to decontaminate the HLW glass canisters to limits that meet USDOE requirements. The equipment includes canister-capping and smear stations in addition to the decontamination module and associated services. 2 refs., 1 fig

  7. Radioactive scrap metal decontamination technology assessment report

    International Nuclear Information System (INIS)

    Buckentin, J.M.; Damkroger, B.K.; Schlienger, M.E.

    1996-04-01

    Within the DOE complex there exists a tremendous quantity of radioactive scrap metal. As an example, it is estimated that within the gaseous diffusion plants there exists in excess of 700,000 tons of contaminated stainless steel. At present, valuable material is being disposed of when it could be converted into a high quality product. Liquid metal processing represents a true recycling opportunity for this material. By applying the primary production processes towards the material's decontamination and re-use, the value of the strategic resource is maintained while drastically reducing the volume of material in need of burial. Potential processes for the liquid metal decontamination of radioactively contaminated metal are discussed and contrasted. Opportunities and technology development issues are identified and discussed. The processes compared are: surface decontamination; size reduction, packaging and burial; melting technologies; electric arc melting; plasma arc centrifugal treatment; air induction melting; vacuum induction melting; and vacuum induction melting and electroslag remelting

  8. Two-step chemical decontamination technology

    International Nuclear Information System (INIS)

    Rankin, W.N.

    1992-01-01

    An improved two-step chemical decontamination technique was recently developed at INEL. This memorandum documents the addition of this technology to the SRTC arsenal of decontamination technology. A two-step process using NAOH, KMnO 4 followed by HNO 3 was used for cleaning doorstops (small casks) in the SRTC High Level Caves in 1967. Subsequently, more aggressive chemical techniques have been found to be much more effective for our applications. No further work on two-step technology is planned

  9. Corrosion surveillance of the chemical decontamination process in Kuosheng nuclear power plant

    International Nuclear Information System (INIS)

    Wang, L.H.

    2002-01-01

    The Piping Recirculation System (RRS) and reactor water clean-up system (RWCU) of Kuosheng Nuclear Power Plant of Taiwan Power Company were decontaminated by CORD process of Framatome ANP GmbH during the outage at October 2001. This is the first time that CORD process was adopted and applied in Taiwan Nuclear Power Plant. To verify minor corrosion damage and correct process control, the material corrosion condition was monitored during all the stages of the chemical decontamination work. Three kinds of specimen were adopted in this corrosion monitoring, including corrosion coupons for weight loss measurements, electrochemical specimens for on-line corrosion monitoring, and WOL specimens (wedge opening loaded) for stress corrosion evaluation. The measured metal losses from nine coupon materials did not reveal any unexpected or intolerable high corrosion damage from the CORD UV or CORD CS processes. The coupon materials included type 304 stainless steel (SS) with sensitized and as-received thermal history, type 308 weld filler, type CF8 cast SS, nickel base alloy 182 weld filler, Inconel 600, Stellite 6 hard facing alloy, NOREM low cobalt hard facing alloy, and A106B carbon steel (CS). The electrochemical noise (ECN) measurements from three-electrode electrochemical probe precisely depicted the metal corrosion variation with the decontamination process change. Most interestingly, the estimated trend of accumulated metal loss is perfectly corresponding to the total removed activities. The ECN measurements were also used for examining the effect of different SS oxide films pre-formed in NWC and HWC on the decontamination efficiency, and for evaluating the galvanic effect of CS with SS. The existing cracks did not propagate further during the decontamination. The average decontamination factors achieved were 50.8 and 4.2 respectively for RRS and RWCU. (authors)

  10. A review of chemical decontamination systems for nuclear facilities

    International Nuclear Information System (INIS)

    Chen, L.; Chamberlain, D.B.; Conner, C.; Vandegrift, G.F.

    1996-01-01

    With the downsizing of the Department of Energy (DOE) complex, many of its buildings and facilities will be decommissioned and dismantled. As part of this decommissioning, some form of decontamination will be required. To develop an appropriate technology for in situ chemical decontamination of equipment interiors in the decommissioning of DOE nuclear facilities, knowledge of the existing chemical decontamination methods is needed. This paper attempts to give an up-to-date review of chemical decontamination methods. This survey revealed that aqueous systems are the most widely used for the decontamination and cleaning of metal surfaces. We have subdivided the aqueous systems by types of chemical solvent: acid, alkaline permanganate, highly oxidizing, peroxide, and proprietary. Two other systems, electropolishing and foams and gels, are also described in this paper

  11. Model decontamination of PVC flooring specimens by wet method

    International Nuclear Information System (INIS)

    Severa, J.; Knajfl, J.; Bar, J.

    1981-01-01

    PVC flooring samples of 29 mm in diameter were used in experiments. The samples were degreased. Tested were the dependence of the degree of contamination on the duration of contact with the contaminant and the efficacy of decontamination by wiping with tampons and immersing in solutions. A mixture of fission products of 80 kBq/ml in specific activity was used for contamination. Higher decontamination efficacy was achieved by immersing the samples in decontamination solutions. Water was found to be the least efficacious medium; a high degree was only attained in the case when decontamination was effected within 1 minute after contamination. The highest decontamination values were achieved using solutions containing a chelating agent and a surfactant. The most efficacious solutions contained 0.5% of citric acid and 0.5% of detergents which are very potent at a concentration as low as 2 g/l. (J.P.)

  12. Contamination, decontamination and radiochemical safety analyses of the RA reactor (Report 1966)

    International Nuclear Information System (INIS)

    Maksimovic, Z.

    1966-12-01

    This contract is concerned with development of methods for detection of fission products i the heavy water and quantitative radiochemical analysis for detecting one fission product which enables reliable verification of heavy water contamination by fission products and estimation of contamination level. Qualitative and quantitative radiometry measurements of fission products in water are shown on page 4. Page 6 shows study of contamination and decontamination of water on the laboratory level. Experiments have shown that the majority of fission products was adsorbed on the uranium oxide and that the iodine isotopes are partly in water (non-adsorbed). Gamma spectrometry analyses showed 131 I moves to distillate with the initial quantities of distilled water. decontamination factors compared to the total activity of fission products in distillator and distillate are not higher than ∼10 3 . Decontamination of water contaminated by uranium oxide and fission products in the distillation device of the RA reactor is shown on page 8. Experiments demanded special preparation due to high activity of uranium (1.7 g of uranium irradiated in the reactor for 10 days at neutron flux 1.10 13 n.cm 2 /s. Prior preparations for transport and dissolution of irradiated metal uranium as well as sampling were needed. Distillation was done under lower pressure and temperature to avoid possible contamination of the environment bu fission products and iodine. Decontamination factors are shown in Table. Contamination and decontamination of stainless steel on the laboratory level are described on page 5. It was found that the deposition of activity on the stainless steel plates is inhomogeneous showing that the uranium oxide and fission products are deposited on the rough metal surfaces. According to literature data and our laboratory studies decontamination was done by nitric acid solution (2MHNO 3 ). Since the heavy water system of the RA reactor was made of stainless teel (except the

  13. Concrete decontamination and demolition methods

    International Nuclear Information System (INIS)

    LaGuardia, T.S.

    1980-01-01

    The US Department of Energy (DOE), Division of Environmental Control Technology, requested Nuclear Energy Services to prepare a handbook for the decontamination and decommissioning (D and D) of DOE-owned and commercially-owned radioactive facilities. the objective of the handbook is to provide the nuclear industry with guidance on the state-of-the-art methods and equipment available for decommissioning and to provide the means to estimate decommissioning costs and environmental impact. The methods available for concrete decontamination and demolition are summarized to provide an overview of some of the state-of-the-art techniques to be discussed at this workshop. The pertinent information on each method will include the selection factors such as the rate of performance in terms of concrete removal per unit time (cubic yards per day), manpower required by craft, unit cost (dollars per cubic yard) and the advantages and disadvantages. The methods included in this overview are those that have been routinely used in nuclear and nonnuclear applications or demonstrated in field tests. These methods include controlled blasting, wrecking ball or slab, backhoe mounted ram, flame torch, thermic lance, rock splitter, demolition compound, sawing, core stitch drilling, explosive cutting, paving breaker and power chisel, drill and spall, scarifying, water cannon and grinding

  14. Development of calculation system for decontamination effect, CDE

    International Nuclear Information System (INIS)

    Satoh, Daiki; Kojima, Kensuke; Oizumi, Akito; Matsuda, Norihiro; Kugo, Teruhiko; Sakamoto, Yukio; Endo, Akira; Okajima, Shigeaki

    2012-08-01

    Large amount of radionuclides had been discharged to environment in the accident of the Tokyo Electric Power Company Fukushima Daiichi Nuclear Power Plant caused by the 2011 off the Pacific coast of Tohoku Earthquake. The radionuclides deposited on the ground elevate dose rates in large area around the Fukushima site. For the reduction of the dose rate and recovery of the environment, decontamination based on a rational plan is an important and urgent subject. A computer software, named CDE (Calculation system for Decontamination Effect), has been developed to support planning the decontamination. CDE calculates the dose rates before the decontamination by using a database of dose contributions by radioactive cesium. The decontamination factor is utilized in the prediction of the dose rates after the decontamination, and dose rate reduction factor is evaluated to express the decontamination effect. The results are visualized on the image of a target zone with color map. In this paper, the overview of the software and the dose calculation method are reported. The comparison with the calculation results by a three-dimensional radiation transport code PHITS is also presented. In addition, the source code of the dose calculation program and user's manual of CDE are attached as appendices. (author)

  15. Effect of Cerium(IV)-Surfactant Reaction in Foam Decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Han Beom; Jung, Chong-Hun; Yoon, In-Ho; Kim, Chorong; Choi, Wang-Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Using foams allows the decommissioning of complex shaped facilities. The decontamination foam comprises at least one surfactant to generate the foam and one or more chemical reactants to achieve the dissolution of the contaminants at the solid surface. In order to improve the efficiency of decontamination foam, the present study attempts to find the optimum condition of chemical reagents to the foaming solution. The corrosion rate of radioactive nuclides contaminated stainless steel metal is very important factor for the foam decontamination process. The goal of this study is to develop the decontamination process for contaminated stainless steel in medium of nitric acid. Stainless steel needs a strong oxidizing agent such as Ce(IV) ion and the effects of cerium(IV). Surfactant interaction involved in foam decontamination and finally the improvement brought by formulation science. The formulation of foams loaded with strong oxidizing reagents such as Ce(IV) is an important factor. The enhanced decontamination properties of nitric acid with Ce(IV) additive on stainless steel is well known in liquid mediums. stainless steel metal is an important aspect in the foam decontamination process.

  16. Effect of Cerium(IV)-Surfactant Reaction in Foam Decontamination

    International Nuclear Information System (INIS)

    Yang, Han Beom; Jung, Chong-Hun; Yoon, In-Ho; Kim, Chorong; Choi, Wang-Kyu

    2015-01-01

    Using foams allows the decommissioning of complex shaped facilities. The decontamination foam comprises at least one surfactant to generate the foam and one or more chemical reactants to achieve the dissolution of the contaminants at the solid surface. In order to improve the efficiency of decontamination foam, the present study attempts to find the optimum condition of chemical reagents to the foaming solution. The corrosion rate of radioactive nuclides contaminated stainless steel metal is very important factor for the foam decontamination process. The goal of this study is to develop the decontamination process for contaminated stainless steel in medium of nitric acid. Stainless steel needs a strong oxidizing agent such as Ce(IV) ion and the effects of cerium(IV). Surfactant interaction involved in foam decontamination and finally the improvement brought by formulation science. The formulation of foams loaded with strong oxidizing reagents such as Ce(IV) is an important factor. The enhanced decontamination properties of nitric acid with Ce(IV) additive on stainless steel is well known in liquid mediums. stainless steel metal is an important aspect in the foam decontamination process

  17. An attemp to use a pulsed CO2 laser for decontamination of radioactive metal surfaces

    Directory of Open Access Journals (Sweden)

    MILAN S. TRTICA

    2000-06-01

    Full Text Available There is a growing interest in laser radioactive decontamination of metal surfaces. It offers advantages over conventional methods: improved safety, reduction of secondary waste, reduced waste volume, acceptable cost. The main mechanism of cleaning by lasers is ablation. A pulsed TEA CO2 laser was used in this work for surface cleaning in order to show that ablation of metal surfaces is possible even at relatively low pulse energies, and to suggest that it could be competitive with other lasers because of much higher energy efficiencies. A brief theoretical analysis was made before the experiments. The laser beam was focused using a KBr-lens onto a surface contaminated with 137Cs (b-, t1/2 = 30.17 y. Three different metals were used: stainless steel, copper and aluminium. The ablated material was pumped out in an air atmosphere and transferred to a filter. The presence of activity on the filter was shown by a germanium detector-multichannel analyzer. The activity levels were measured by a GM counter. The calculated decontamination factors and collection factors showed that ablation occurs with a relatively high efficiency of decontamination. This investigation suggests that decontamination using a CO2 laser should be seriously considered.

  18. Possibilities of a metal surface radioactive decontamination using a pulsed CO2 laser

    Science.gov (United States)

    Milijanic, Scepan S.; Stjepanovic, Natasa N.; Trtica, Milan S.

    2000-01-01

    There is a growing interest in the laser radioactive decontamination of metal surfaces. It offers advantages over conventional methods: improved safety, reduction of secondary waste, reduced waste volume, acceptable cost. A main mechanism of cleaning in by lasers is ablation. In this work a pulsed TEA CO2 laser was used for surface cleaning, primarily in order to demonstrate that the ablation from metal surfaces with this laser is possible even with relatively low pulse energies, and secondary, that it could be competitive with other lasers because of much higher energy efficiencies. The laser pulse contains two parts, one strong and shot peak at the beginning, followed with a tail. The beam was focused onto a contaminated surface with a KBr lens. The surface was contaminated with 137Cs. Three different metals were used: stainless steel, copper and aluminum. The evaporated material was pumped out in air atmosphere and transferred to a filter. Presence of the activity on the filter was proved by a germanium detector-multichannel analyzer. Activity levels were measured by a GM counter. Calculated decontamination factors as well as collection factors have shown that ablation takes place with relatively high efficiency of decontamination. This investigation suggests that decontamination using the CO2 laser should be seriously considered.

  19. Soil decontamination with Extraksol

    International Nuclear Information System (INIS)

    Paquin, J.; Mourato, D.

    1989-01-01

    The Extraksol process is a mobile decontamination technology which treats unconsolidated materials by solvent extraction. Treatment with Extraksol involves material washing, drying and solvent regeneration. Contaminant removal is achieved through desorption/dissolution mechanisms. The treated material is dry and acceptable to be reinstalled in its original location. The process provides a fast, efficient and versatile alternative for decontamination of soil and sludge. The organic contaminants extracted from the matrix are transferred to the extraction fluids. These are thereafter concentrated in the residues of distillation after solvent regeneration. Removal and concentration of the contaminants ensures an important waste volume reduction. This paper presents the process is operational principles and the steps involved in Extraksol's development with results of the pilot tests and full-scale demonstrations

  20. Sunflowers to decontaminate water

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    Sunflowers offer a new method of decontamination. 55 kilograms (dry weight) of sunflowers are able to decontaminate all the cesium 137 and the strontium 90 polluting a pond situated at one kilometer from Tchernobyl. These flowers are able to decrease 95% in 24 hours the uranium concentration in the american site of Ashtabula in Ohio getting this water from 350 parts by milliards to less than 5 parts by milliards. The radioactivity should stocked in the roots at concentrations 5 000 to 10 000 times higher than water concentration. The cost is cheaper than micro filtration and precipitation (2-6 dollars for 4 000 liters of water against 80 dollars for others technologies). when sunflowers are radioactive they can be reduced in dust and vitrified and stocked as solid radioactive wastes. (N.C.)

  1. OPO fabric decontamination

    International Nuclear Information System (INIS)

    Severa, J.; Bar, J.; Grujbar, V.

    1978-01-01

    Samples of five polypropylene-based man-made fabrics were studied with regard to the degree of contamination and possibilities of decontamination in order to assess their suitability as material for protective clothing in the nuclear industry. The contamination degree of the fabrics in an aqueous solution of a fission product mixture was found to be low. Soaking in a mixture of the Sapon detergent and sodium hexametaphosphate at a concentration of both materials of 1 g/l with subsequent washing in a solution of the Zenit detergent at a concentration of 3 g/l was suggested as the most suitable decontamination procedure. It reduces the initial contamination by almost 99%. (Z.M.)

  2. Chemical decontamination for decommissioning purposes. (Vigorous decontamination tests of steel samples in a special test loop)

    International Nuclear Information System (INIS)

    Bregani, F.; Pascali, R.; Rizzi, R.

    1984-01-01

    The aim of the research activities described was to develop vigorous decontamination techniques for decommissioning purposes, taking into account the cost of treatment of the radwaste, to achieve possibly unrestricted release of the treated components, and to obtain know-how for in situ hard decontamination. The decontamination procedures for strong decontamination have been optimized in static and dynamic tests (DECO-loop). The best values have been found for: (i) hydrochloric acid: 4 to 5% vol. at low temperature, 0.7 to 1% vol. at high temperature (80 0 C); (ii) hydrofluoric plus nitric acid: 1.5% vol. HF + 5% vol. HNO 3 at low temperature; 0.3 to 0.5% vol. HF + 2.5 to 5% vol. HNO 3 at high temperature. High flow rates are not necessary, but a good re-circulation of the solution is needed. The final contamination levels, after total oxide removal, are in accordance with limits indicated for unrestricted release of materials in some countries. The arising of the secondary waste is estimated. Decontamination of a 10 m 2 surface would typically produce 0.5 to 3.0 kg of dry waste, corresponding to 1.6 to 10 kg of concrete conditioned waste

  3. Sensitive Equipment Decontamination

    Science.gov (United States)

    2017-10-01

    a ceramic-like material Polonium - 210 Metallic foil Radium-226 Radium bromide or radium chloride Strontium-90 Metallic strontium, strontium...extremely toxic toxins. 3.1.1.5 Routes of Infection Pathogenic microorganisms are transferred to human beings largely via air and food (including...regularly in the pharmaceutical industry to decontaminate manufacturing clean rooms. It is also used to sterilize packages used to store foods . It has

  4. Decommissioning and decontamination

    International Nuclear Information System (INIS)

    Dadoumont, J.; Cantrel, E.; Valenduc, P.; Noynaert, L.

    2009-01-01

    The SCK-CEN has built a large know-how in decommissioning and decontamination, thanks to its BR3 decommissioning project. In 2007, the decommissioning activities at BR3 have been continued according to the strategy. This article discusses main realisations the following domains: decommissioning of the neutron shield tank and installation of new ventilation for the controlled area, dismantling of the former one and characterization of the stack

  5. Neuronal factors determining high intelligence.

    Science.gov (United States)

    Dicke, Ursula; Roth, Gerhard

    2016-01-05

    Many attempts have been made to correlate degrees of both animal and human intelligence with brain properties. With respect to mammals, a much-discussed trait concerns absolute and relative brain size, either uncorrected or corrected for body size. However, the correlation of both with degrees of intelligence yields large inconsistencies, because although they are regarded as the most intelligent mammals, monkeys and apes, including humans, have neither the absolutely nor the relatively largest brains. The best fit between brain traits and degrees of intelligence among mammals is reached by a combination of the number of cortical neurons, neuron packing density, interneuronal distance and axonal conduction velocity--factors that determine general information processing capacity (IPC), as reflected by general intelligence. The highest IPC is found in humans, followed by the great apes, Old World and New World monkeys. The IPC of cetaceans and elephants is much lower because of a thin cortex, low neuron packing density and low axonal conduction velocity. By contrast, corvid and psittacid birds have very small and densely packed pallial neurons and relatively many neurons, which, despite very small brain volumes, might explain their high intelligence. The evolution of a syntactical and grammatical language in humans most probably has served as an additional intelligence amplifier, which may have happened in songbirds and psittacids in a convergent manner. © 2015 The Author(s).

  6. Laser decontamination device

    International Nuclear Information System (INIS)

    Michishita, Shizuo; Akagawa, Katsuhiko.

    1997-01-01

    One end of an optical fiber inserted into an inner cylinder is opposed to a wall surface to be decontaminated, and an opened top end of an intermediate cylinder circumferentially surrounding the inner cylinder is tightly in contact with the wall surface to be decontaminated, an open end of an outer cylinder circumferentially surrounding the intermediate cylinder is tightly in contact with the wall surface to be decontaminated. Dust removing holes are perforated in the vicinity of the top end of the intermediate cylinder while being in communication with the inside and the outside of the intermediate cylinder, and one end of an air supply tube is in communication with the space between the outer circumferential surface of the inner cylinder and the inner circumferential surface of the intermediate cylinder. The other end of the air supply tube is connected to an air supply device, one end of a sucking tube is in communication with the space between the outer circumferential surface of the intermediate cylinder and the inner circumferential surface of the outer cylinder, the other end of the sucking tube is connected to a sucking device, and the other end of the optical fiber is connected to a laser generation device. The laser generation device is operated while determining the air sucking amount increased than the air supply amount, the materials deposited on the wall surface are crushed and peeled off, and the peeled off materials are transferred by air flow to a filter and collected. (N.H.)

  7. Decontamination impacts on solidification

    International Nuclear Information System (INIS)

    Piciulo, P.L.; Davis, M.S.

    1985-01-01

    The increased occupational exposure resulting from the accumulation of activated corrosion products in the primary system of LWRs has led to the development of chemical methods to remove the contamination. In the past, the problem of enhanced migration of radionuclides away from trenches used to dispose of low-level radioactive waste, has been linked to the presence, at the disposal unit, of chelating or complexing agents such as those used in decontamination processes. These agents have further been found to reduce the normal sorptive capacity of soils for radionuclides. The degree to which these agents inhibit the normal sorptive processes is dependent on the type of complexing agent, the radionuclide of concern, the soil properties and whether the nuclide is present as a complex or is already sorbed to the soil. Since the quantity of reagent employed in a full system decontamination is large (200 to 25,000 kg), the potential for enhanced migration of radionuclides from a site used to dispose of the decontamination wastes should be addressed and guidelines established for the safe disposal of these wastes

  8. Building surface decontamination for chemical counter-terrorism

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, S.; Thouin, G.; Kuang, W. [SAIC Canada, Ottawa, ON (Canada); Volchek, K.; Fingas, M.; Li, K. [Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Division, Environmental Technology Centre, Science and Technology Branch

    2006-07-01

    A test method to compare and evaluate surface decontamination methods for buildings affected by chemical attacks was developed. Decontamination techniques generally depend on the nature and quantity of the weapon agent, the type of construction material and the location. Cleanup methods can be either physical, chemical or biological. This paper addressed chemical decontamination methods which use reactants to change the molecular structure of the contaminant. Peroxycarboxylic and peroxyacetic acids (PAA) are being used increasingly for both disinfection and environmental protection. In this study, 4 materials were chosen to represent common building materials. Samples were spiked with 10 mg of pesticides such as malathion and diazinon. Decontamination agents included the commercial decontamination agent CASCAD prepared in liquid form, a chemical preparation of PAA, and reagent grade peroxypropionic acid (PPA). The newly developed surface decontamination procedure can evaluate and compare the effectiveness of different chemical decontamination agents. The procedures were used on porous ceiling tile and carpet as well as on non-porous floor tile and painted steel surfaces. Rinse water was collected and analyzed in order to determine if decontamination was a result of chemical destruction or mechanical removal. The extraction efficiencies were found to be acceptable for all materials, with the exception of the highly porous ceiling tile. The extraction of diazinon from all surfaces was less efficient than the extraction of malathion. Results suggest that the performance of decontamination agents can be improved by repeated application of the decontamination agent, along with greater volumes and a combination of chemical and mechanical actions. It was also suggested that breakdown methods and wastewater treatment procedures should be developed because hazardous byproducts were detected in many samples. 18 refs., 1 tab., 17 figs.

  9. Overview of nonchemical decontamination techniques

    International Nuclear Information System (INIS)

    Allen, R.P.

    1984-09-01

    The decontamination techniques summarized in this paper represent a variety of surface cleaning methods developed or adapted for component and facility-type decontamination applications ranging from small hand tools to reactor cavities and other large surface areas. The major conclusion is that decontamination is a complex, demanding technical discipline. It requires knowledgeable, experienced and well-trained personnel to select proper techniques and combinations of techniques for the varied plant applications and to realize their full performance potential. Unfortunately, decontamination in many plants has the lowest priority of almost any activity. Operators are unskilled and turnover is so frequent that expensive decontamination capabilities remain unused while decontamination operations revert to the most rudimentary type of hand scrubbing and water spray cleaning

  10. Complexon Solutions in Freon for Decontamination of Solids and SNF Treatment

    International Nuclear Information System (INIS)

    Kamachev, V.; Shadrin, A.; Murzin, A.

    2008-01-01

    Full text of publication follows: The possibility of using complexon solutions in supercritical and compressed carbon dioxide for decontamination of solid surfaces and for spent nuclear fuel (SNF) treatment was demonstrated in the works of Japanese, Russian and American researchers. The obtained data showed that the use of complexon solutions in carbon dioxide sharply decreases the volume of secondary radioactive wastes because it can be easily evaporated, purified and recycled. Moreover, high penetrability of carbon dioxide allows decontamination of surfaces with complex shape. However, one of the disadvantages of carbon dioxide is its high working pressure (10-20 MPa for supercritical CO 2 and 7 MPa for compressed CO 2 ). Moreover, in case of SNF treatment, carbon dioxide solvent will be contaminated with 14 C, which in the course of SNF dissolution in CO 2 containing TBP*HNO 3 adduct stage will be oxidized into CO 2 . These main disadvantages can be eliminated by using complexon solutions in ozone-friendly Freon HFC-134a for decontamination and SNF treatment. Our experimental data for real contaminated materials showed that the decontamination factor for complexon solutions in liquid Freon HFC-134a at 1,2 MPa and 25 deg. C is close to that attained in carbon dioxide. Moreover, the possibility of SNF treatment in Freon HFC-134a was demonstrated in trials using real SNF and its imitators. (authors)

  11. Study on decontamination of radioactive ruthenium by steel wool in waste solution

    Energy Technology Data Exchange (ETDEWEB)

    Sugimoto, S; Sakaki, T [Radia Industry Co. Ltd., Takasaki, Gunma (Japan)

    1979-06-01

    Tracer experiments were done in order to establish a decontamination process of /sup 106/Ru in radioactive waste solution by column method paying special attention on the solution of nitrato-nitrosyl complex of Ru which is often encountered as a low level radioactive solution. It turned out that metallic iron was the most effective decontaminating agent among the several tens of materials tested. The decontamination factor (DF) of /sup 106/Ru increased in proportion to the total surface area of iron and it sensitively depended on the oxidation state of the surface as revealed by the batchwise and columnwise tests. Iron samples with high corrosiveness gave a much larger DF than those with low corrosiveness. The decontamination process proceeded as iron was being oxidized via Fe(metal) ..-->.. Fe(II) ..-->.. Fe(III). As the results, the DF initially increased after initiating the passage of water through the column but it then decreased as the oxidation process became inactive. An excellent durability up to 10000 bed volumes was demonstrated by the column method at a high average DF of 150.

  12. Decontamination of operational nuclear power plants

    International Nuclear Information System (INIS)

    1981-06-01

    In order to reduce the radiation fields around nuclear power plants, and, consequently, to limit the radiation exposure of and dose commitments to the operating and maintenance personnel, the contamination build-up should be kept to a minimum. The most fruitful approach, from the point of view of economics and efficiency, is to tackle the problems of contamination and decontamination in the design and construction phases of the reactor. To do this, knowledge gained from the operation of existing power reactors should be used to make improvements in new designs. New structural materials with low corrosion rates or whose constituents are not activated by neutrons should also be used. For older reactors, in most cases it is already too late to incorporate design changes without extensive and expensive modifications. For these plants, decontamination remains the most efficient way to reduce radiation fields. The aim of this report is to deal with the different decontamination methods that may be applied to nuclear power plant circuits and equipment during operation. The factors that have to be considered in determining the type and the extent of the methods used are the engineering and the planning of the decontamination operation and the treatment of the resulting waste generated during the process are also discussed

  13. Thermal decontamination of transformers: A new technology

    International Nuclear Information System (INIS)

    Colak, P.Z.

    1992-01-01

    After evaluating a number of methods for decontaminating or disposing of transformers that contained polychlorinated biphenyls (PCB), it was concluded that no entirely satisfactory procedure or technology was yet available which was permanent, effective, safe, relatively simple, and based on proven technology or conventional practice. The most desirable compromise appears to be thermal decontamination. It is proposed to decontaminate transformers by controlled incineration in a specially designed, indirect-fired furnace which resembles the conventional bell-type, vertical elevator, metal heat treating type of furnace. The design differs in the incorporation of those essential features required to achieve oxidation of the organic components, to provide internal air circulation needed to ensure efficient heat and mass transfer, and other factors. The most appropriate decontamination facility would provide for implementation of the following procedures: draining of PCB-containing liquids from the transformer; limited disassembly of the transformer, which in most instances would imply only removal of the top cover to expose the insides; and controlled incineration with any vapors generated being conducted to a secondary combustion chamber. Experiments were conducted in a kiln to simulate the proposed transformer incinerator. Results show that exposure of the transformer segments to a temperature in the 950-1,000 degree C range for over 90 min is generally sufficient to reduce the PCB content to under 1 ppM. Based on the work conducted, a suitable bell furnace was constructed and added to the Swan Hills (Alberta) waste treatment facility. 2 figs., 3 tabs

  14. Manual on decontamination of surfaces

    International Nuclear Information System (INIS)

    1979-01-01

    The manual is intended for those who are responsible for the organization and implementation of decontamination programmes for facilities where radioactive materials are handled mainly on a laboratory scale. It contains information and guidelines on practical methods for decontaminating working spaces, equipment, laboratory benches and protective clothing. Useful information is also provided on the removal of loose skin contamination from personnel by mild, non-medical processes. Methods of removing skin contamination needing medical supervision, or of internal decontamination, which is entirely a medical process, are not covered in this manual. Large-scale decontamination of big nuclear facilities is also considered as outside its scope

  15. Use of citric acid for large parts decontamination

    International Nuclear Information System (INIS)

    Holland, M.E.

    1979-01-01

    Laboratory and field studies have been performed to identify and evaluate chemical decontamination agents to replace ammonium carbonate, an environmentally unacceptable compound, in the decontamination facility for large process equipment at the Portsmouth Gaseous Diffusion Plant. Preliminary screening of over 40 possible decontamination agents on the basis of efficiency, availability, toxicity, cost, corrosiveness, and practicality indicated sodium carbonate and citric acid to be the most promising. Extensive laboratory studies were performed with these two reagents. Corrosion rates, decontamination factors, uranium recovery efficiencies, technetium ( 99 Tc)/ion exchange removal effects, and possible environmental impacts were determined or investigated. Favorable results were found in all areas. Detailed monitoring and analysis during two-week trial periods in which sodium carbonate and citric acid were used in the large parts decontamination facility resulted in similar evaluation and conclusions. Because it has cleaning properties not possessed by sodium carbonate, and because it eliminated several operational problems by incorporating two acidic decontamination reagents (citric and nitric acids) instead of one basic reagent (sodium or ammonium carbonate) and one acidic reagent (nitric acid), citric acid was selected for one-year field testing. On the basis of its excellent performance in the field tests, citric acid is recommended as a permanent replacement for ammonium carbonate in the decontamination facility for large process equipment

  16. GARDEC, Estimation of dose-rates reduction by garden decontamination

    International Nuclear Information System (INIS)

    Togawa, Orihiko

    2006-01-01

    1 - Description of program or function: GARDEC estimates the reduction of dose rates by garden decontamination. It provides the effect of different decontamination Methods, the depth of soil to be considered, dose-rate before and after decontamination and the reduction factor. 2 - Methods: This code takes into account three Methods of decontamination : (i)digging a garden in a special way, (ii) a removal of the upper layer of soil, and (iii) covering with a shielding layer of soil. The dose-rate conversion factor is defined as the external dose-rate, in the air, at a given height above the ground from a unit concentration of a specific radionuclide in each soil layer

  17. Biodegradation of concrete intended for their decontamination; Biodegradation de matrices cimentaires en vue de leur decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Jestin, A

    2005-05-15

    The decontamination of sub-structural materials represents a stake of high importance because of the high volume generated. It is agreed then to propose efficient and effective processes. The process of bio-decontamination of the hydraulic binders leans on the mechanisms of biodegradation of concretes, phenomenon characterized in the 40's by an indirect attack of the material by acids stem from the microbial metabolism: sulphuric acid (produced by Thiobacillus), nitric acid (produced by Nitrosomonas and Nitrobacter) and organic acids (produced by fungi). The principle of the bio-decontamination process is to apply those microorganisms on the surface of the contaminated material, in order to damage its surface and to retrieve the radionuclides. One of the multiple approaches of the process is the use of a bio-gel that makes possible the micro-organisms application. (author)

  18. Method of recovering phosphoric acid type decontaminating electrolytes by electrodeposition

    International Nuclear Information System (INIS)

    Sasaki, Takashi; Wada, Koichi; Kobayashi, Toshio.

    1985-01-01

    Purpose: To recoving phosphoric acid type highly concentrated decontaminating liquid used for the electrolytic decontamination of contaminated equipments, components, etc in nuclear power plants or the like through electrodeposition by diaphragm electrolysis. Method: Before supplying phosphoric acid decontaminating liquid at high concentration used in the electrolytic decontaminating step to an electrodeposition recovering tank, phosphoric acid in the decontaminating electrolyte is extracted with solvents and decomposed liquid extracts (electrolyte reduced with the phosphoric acid component) are supplied to the cathode chamber of the electrodeposition recovering tank, where phosphoric acid is back-extracted with water from the solvents after extraction of phosphoric acid. Then, the back-extracted liquids (aqueous phosphoric acid solution scarcely containing metal ions) are sent to the anode chamber of the electrodeposition recovering tank. Metal ions in the liquid are captured by electrodeposition in the cathode chamber, as well as phosphoric acid in the liquids is concentrated to the initial concentration of the electrolyte in the anode chamber for reuse as the decontaminating electrolyte. As the phosphoric acid extracting agent used in the electrodeposition recovering step for the decontaminating electrolyte, water-insoluble and non-combustible tributyl phosphate (TBP) is most effective. (Horiuchi, T.)

  19. Study of decontamination and radiation resistance properties of Indian paints

    International Nuclear Information System (INIS)

    Shah, S.M.; Gopinathan, E.; Bhagwath, A.M.

    1976-01-01

    A brief introduction to the study of contamination and radiation resistance properties of Indian paints used as coating for structural materials in the nuclear industry is given. The general composition of paints such as epoxy, vinyl, alkyd, phenolic, chlesimated rubber, etc. is given. Method of sample preparation, processing and actual evaluation of decontaminability are described. The results have been discussed in terms of decontamination factors. Some recommendations based on the performance of the paints studied are also included. (K.B.)

  20. Full system decontamination. AREVAs experience in decontamination prior to decommissioning

    International Nuclear Information System (INIS)

    Topf, Christian

    2010-01-01

    Minimizing collective radiation exposure and producing free-release material are two of the highest priorities in the decommissioning of a Nuclear Power Plant (NPP). Full System Decontamination (FSD) is the most effective measure to reduce source term and remove oxide layer contamination within the plant systems. FSD is typically a decontamination of the primary coolant circuit and the auxiliary systems. In recent years AREVA NP has performed several FSDs in PWRs and BWRs prior to decommissioning by applying the proprietary CORD copyright family and AMDA copyright technology. Chemical Oxidation Reduction Decontamination or CORD represents the chemical decontamination process while AMDA stands for Automated Mobile Decontamination Appliance, AREVA NPs decontamination equipment. Described herein are the excellent results achieved for the FSDs applied at the German PWRs Stade in 2004 and Obrigheim in 2007 and for the FSDs performed at the Swedish BWRs, Barsebaeck Unit 1 in 2007 and Barsebaeck Unit 2 in 2008. All four FSDs were performed using the AREVA NP CORD family decontamination technology in combination with the AREVA NP decontamination equipment, AMDA. (orig.)

  1. Decontamination of Soil Contaminated with Bacillus anthracis ...

    Science.gov (United States)

    Technical Brief This technical summary will provide decontamination personnel rapid access to information on which decontamination approaches are most effective for soils contaminated with B anthracis.

  2. Remote methods for decontamination and decommissioning operations

    International Nuclear Information System (INIS)

    DeVore, J.R.

    1986-01-01

    Three methods for the decontamination and decommissioning of nuclear facilities are described along with operational experience associated with each method. Each method described in some way reduces radiation exposure to the operating personnel involved. Electrochemical decontamination of process tanks is described using an in-situ method. Descriptions of two processes, electropolishing and cerium redox decontamination, are listed. A method of essentially smokeless cutting of process piping using a plasma-arc cutting torch is described. In one technique, piping is cut remotely from a distance using a specially modified torch holder. In another technique, cutting is done with master-slave manipulators inside a hot cell. Finally, a method for remote cutting and scarification of contaminated concrete is described. This system, which utilizes high-pressure water jets, is coupled to a cutting head or rotating scarification head. The system is suited for cutting contaminated concrete for removal or removing a thin layer in a controlled manner for decontamination. 4 refs., 6 figs

  3. Decontamination for radiators by friction effect

    International Nuclear Information System (INIS)

    Nojima, Takeshi; Yoshida, Yuji

    2016-01-01

    Radiators are equipped with cars, vending machines and outdoor units of air conditioners. Aluminum metal surfaces in their heat exchange part have been contaminated by radioactive material taking in dust after the nuclear accident. The dust adhering to the metal surface could be removed by flushing with water immediately after scattering radioactive material. But radioactive material such as cesium cannot be removed by water washing, because of growth of the oxide film and transfer of the nuclides in the metal surface due to aging. On the other hand, we have verified the effect of decontamination of radiators by friction cleaning using a cross flow shredder (CFS) and solvent washing of crushed metallic chips, as a different approach to high-pressure washing decontamination, and confirmed a certain decontamination effect. This paper describes the results of program, “Processing Technology of Radioactive Material Removal by Cross Flow Shredder,” in August to December 2015, on support of FY 2015 Demonstration Test Project for Decontamination and Volume Reduction of Ministry of the Environment. (author)

  4. Cleaning and decontamination: Experimental feedback from PHENIX

    International Nuclear Information System (INIS)

    Masse, F.; Rodriguez, G.

    1997-01-01

    After the first few years of operation of PHENIX, it proved necessary to clean, then decontaminate sodium-polluted components, particularly large components such as the intermediate heat exchangers (IHX) and the primary pumps (PP). Ibis document presents the evolution of the cleaning and decontamination processes used, and specifies the reasons for this evolution. As regards the cleaning, experimental feedback and a greater rigour with respect to the hydrogen hazard have resulted in a modification of the process. The new cleaning process used at present (since 1994) is described in greater detail in this document. The main steps are: cold CO 2 bubbling in water, followed by hot CO 2 bubbling, spraying phase, then drying for inspection before immersion. In order to optimize and validate the process, the cleaning and decontamination plant has been highly instrumented, which, in particular, has allowed confirmation of the contention that the major part of the sodium is eliminated during the bubbling phases. With respect to decontamination, the objective is to perfect an efficient process that allows both human intervention with no particular biological shield for repair or maintenance of the components, and requalification of the materials after the decontamination operation. Owing to the high operating temperature of Fast Breeder Reactor components (400 to 550 deg. C), the activated corrosion products deposited on the components melt into the metal. The decontamination process therefore consists in either dissolving the deposits on the surface, or dissolving a thickness of about less than ten micrometers of the base metal. The reference process for austenitic-type steels is the SPm process, which consists in immersing the component in a sulphuric-phosphoric bath (sulphuric acid and phosphoric acid) at a temperature of 60 deg. C for 6 hours. The problem linked to this process is the treatment of the effluents that are produced, particularly phosphate releases. A

  5. Understanding Mechanism of Photocatalytic Microbial Decontamination of Environmental Wastewater

    Directory of Open Access Journals (Sweden)

    Chhabilal Regmi

    2018-02-01

    Full Text Available Several photocatalytic nanoparticles are synthesized and studied for potential application for the degradation of organic and biological wastes. Although these materials degrade organic compounds by advance oxidation process, the exact mechanisms of microbial decontamination remains partially known. Understanding the real mechanisms of these materials for microbial cell death and growth inhibition helps to fabricate more efficient semiconductor photocatalyst for large-scale decontamination of environmental wastewater or industries and hospitals/biomedical labs generating highly pathogenic bacteria and toxic molecules containing liquid waste by designing a reactor. Recent studies on microbial decontamination by photocatalytic nanoparticles and their possible mechanisms of action is highlighted with examples in this mini review.

  6. Laser Decontamination of Surfaces Contaminated with Cs+ Ion

    International Nuclear Information System (INIS)

    Baigalmaaa, B.; Won, H. J.; Moon, J. K.; Jung, C. H.; Lee, K. W.; Hyun, J. H.

    2008-01-01

    Laser decontamination technology has been proven to be an efficient method for a surface modification of metals and concretes contaminated with radioactive isotopes. Furthermore, the generation of a secondary waste is negligible. The radioactivity of hot cells in the DFDF (Dupic Fuel Development Facility) is presumed to be very high and the predominant radionuclide is Cs-137. A series of laser decontamination studies by a fabricated Q-switched Nd:YAG laser system were performed on stainless steel specimens artificially contaminated with Cs+ ion. Decontamination characteristics of the stainless steel were analyzed by SEM and EPMA

  7. Systematic chemical decontamination using IF7 gas - 59036

    International Nuclear Information System (INIS)

    Hata, Haruhi; Yokoyama, Kaoru; Sugitsue, Noritake

    2012-01-01

    Since 1979, Uranium enrichment technology has been researched through the gas centrifuge method, at Ningyo-toge Environmental Engineering Center of Japan Atomic Energy Agency (JAEA). In addition, the Demonstration Plant, that is final stage test facilities, was operating continuously from 1988 to 2001. As a result, a lot of residues accumulated in the plant. Most of this accumulation was found be uranium intermediate fluoride. The basic decommission policy of JAEA is that equipments of gas centrifuge will be decontaminated by sulfuric acid immersion method for clearance and reuse. In our plan, approximately 90% of metals will be cleared and reused, and then the remaining 10% will be disposed of radioactive waste. We propose a combination of sulfuric acid immersion method and the systematic chemical decontamination as an efficient method for decontamination of uranium enrichment facilities. This paper focuses on the method and performance of systematic chemical decontamination using IF 7 gas. The following (Figure 1) shows our decommission policy and position of systematic chemical decontamination by IF 7 gas for uranium enrichment plant. The IF 7 treatment technique belongs to the systematic decontamination technology. It has the high performance decontamination technique for the plant that accumulates the uranium intermediate fluoride, such as UF 4 , UF 5 , U 2 F 9 , and U 4 F 17 , which exist in the uranium enrichment plant through the Gas Centrifuge, called GCF. The one of characteristics of the IF 7 treatment, the secondary waste is just an IF 5 and little residues. In addition, this IF 5 can be reused as materials for making new IF 7 gas. The IF 7 treatment can also be performed in the room temperature and very low pressure like a 10-45 hPa. Furthermore, the IF 7 treatment is a simple method using chemical reaction. For this reason, we hardly need to care about secondary reaction with the exception of the reaction with IF 7 gasand the uranium intermediate

  8. Planning guidance for nuclear-power-plant decontamination. [PWR; BWR

    Energy Technology Data Exchange (ETDEWEB)

    Munson, L.F.; Divine, J.R.; Martin, J.B.

    1983-06-01

    Direct and indirect costs of decontamination are considered in the benefit-cost analysis. A generic form of the benefit-cost ratio is evaluated in monetary and nonmonetary terms, and values of dollar per man-rem are cited. Federal and state agencies that may have jurisiction over various aspects of decontamination and waste disposal activities are identified. Methods of decontamination, their general effectiveness, and the advantages and disadvantages of each are outlined. Dilute or concentrated chemical solutions are usually used in-situ to dissolve the contamination layer and a thin layer of the underlying substrate. Electrochemical techniques are generally limited to components but show high decontamination effectiveness with uniform corrosion. Mechanical agents are particularly appropriate for certain out-of-system surfaces and disassembled parts. These processes are catagorized and specific concerns are discussed. The treatment, storage, and disposal or discharge or discharge of liquid, gaseous, and solid wastes generated during the decontamination process are discussed. Radioactive and other hazardous chemical wastes are considered. The monitoring, treatment, and control of radioactive and nonradioactive effluents, from both routine operations and possible accidents, are discussed. Protecting the health and safety of personnel onsite during decontamination is of prime importance and should be considered in each facet of the decontamination process. The radiation protection philosophy of reducing exposure to levels as low as reasonably achievable should be stressed. These issues are discussed.

  9. Development of Decontamination and Decommissioning Technologies for Nuclear Facilities

    International Nuclear Information System (INIS)

    Moon, Jei Kwon; Lee, Kune Woo; Won, Hui Jun

    2010-04-01

    A laser ablation decontamination technology which is reportedly effective for a removal of fixed contaminants has been developed for three years as the first stage of the development. Lab scale experimental equipment was fabricated and the process variables have been assessed for determination of appropriate decontamination conditions at the laser wave lengths of 1,064 nm and 532 nm, respectively. The decontamination tests using radioactive specimens showed that the decontamination efficiency was about 100 which is quite a high value. An electrokinetic-flushing, an agglomeration leaching and a supercritical CO 2 soil decontamination technology were development for a decontamination of radioactive soil wastes from the decommissioned sites of the TRIGA research reactor and the uranium conversion facilities. An electrokinetic-flushing process was found to be effective for soil wastes aged for a long time and an agglomeration leaching process was effective for soil wastes of surface contamination. On the other hand, a supercritical CO 2 soil decontamination technology was found to be applicable for U or TRU bearing soil wastes. The remediation monitoring key technologies such as a representative sample taking and a measurement concept for the vertical distribution of radionuclides were developed for an assessment of the site remediation. Also an One-Dimensional Water Flow and Contaminant Transport in Unsaturated Zone (FTUNS) code was developed to interpretate the radionuclide migration in the unsaturated zone

  10. Unit for air decontamination

    International Nuclear Information System (INIS)

    Mariano H, E.

    1991-02-01

    To fulfill the applicable requirements of safety to the ventilation systems in nuclear facilities, it is necessary to make a cleaning of the air that hurtles to the atmosphere. For that which was designed and it manufactured an unit for decontamination of the air for the Pilot plant of production of Nuclear Fuel that this built one with national parts, uses Hepa national filters and the design can adapt for different dimensions of filters, also can be added a lodging for a prefilter or to adopt two Hepa filters. (Author)

  11. Decontamination solution development studies

    International Nuclear Information System (INIS)

    Allen, R.P.; Fetrow, L.K.; Kjarmo, H.E.; Pool, K.H.

    1993-09-01

    This study was conducted for the Westinghouse Hanford Company (WHC) by Pacific Northwest Laboratory (PNL) as part of the Hanford Grout Technology Program (HGTP). The objective of this study was to identify decontamination solutions capable of removing radioactive contaminants and grout from the Grout Treatment Facility (GTF) process equipment and to determine the impact of these solutions on equipment components and disposal options. The reference grout used in this study was prepared with simulated double-shell slurry feed (DSSF) and a dry blend consisting of 40 wt % limestone flour, 28 wt % blast furnace slag, 28 wt % fly ash, and 4 wt % type I/II Portland cement

  12. Archives decontamination by gamma irradiation

    International Nuclear Information System (INIS)

    Bratu, E.; Moise, I.V.; Cutrubinis, M.; Negut, D.C.; Virgolici, Marian

    2009-01-01

    The treatment of archives with gamma irradiation is an efficient and environmental friendly alternative for biological decontamination of large volume of archives. It substitutes the use of chemicals for conservation and contributes to safer workplaces. This work is targeting documents from recent archives where the value of information is not obsolete and may become an important historical and cultural testimony. For a successful treatment, an optimal absorbed dose has to be established. An excessive dose may damage papers and an insufficient one will not reduce bioburden to the desired level. An interdisciplinary team was performing various physical and chemical tests in order to evaluate deterioration of paper at high doses. In the case of natural disaster, it is not excluded the '' emergency '' treatment for documents in immediate danger of total destruction. (authors)

  13. Decontamination formulation with sorbent additive

    Science.gov (United States)

    Tucker; Mark D. , Comstock; Robert H.

    2007-10-16

    A decontamination formulation and method of making that neutralizes the adverse health effects of both chemical and biological compounds, especially chemical warfare (CW) and biological warfare (BW) agents, and toxic industrial chemicals. The formulation provides solubilizing compounds that serve to effectively render the chemical and biological compounds, particularly CW and BW compounds, susceptible to attack, and at least one reactive compound that serves to attack (and detoxify or kill) the compound. The formulation includes at least one solubilizing agent, a reactive compound, a bleaching activator, a sorbent additive, and water. The highly adsorbent, water-soluble sorbent additive (e.g., sorbitol or mannitol) is used to "dry out" one or more liquid ingredients, such as the liquid bleaching activator (e.g., propylene glycol diacetate or glycerol diacetate) and convert the activator into a dry, free-flowing powder that has an extended shelf life, and is more convenient to handle and mix in the field.

  14. Highly crystallized nanometer-sized zeolite a with large Cs adsorption capability for the decontamination of water.

    Science.gov (United States)

    Torad, Nagy L; Naito, Masanobu; Tatami, Junichi; Endo, Akira; Leo, Sin-Yen; Ishihara, Shinsuke; Wu, Kevin C-W; Wakihara, Toru; Yamauchi, Yusuke

    2014-03-01

    Nanometer-sized zeolite A with a large cesium (Cs) uptake capability is prepared through a simple post-milling recrystallization method. This method is suitable for producing nanometer-sized zeolite in large scale, as additional organic compounds are not needed to control zeolite nucleation and crystal growth. Herein, we perform a quartz crystal microbalance (QCM) study to evaluate the uptake ability of Cs ions by zeolite, to the best of our knowledge, for the first time. In comparison to micrometer-sized zeolite A, nanometer-sized zeolite A can rapidly accommodate a larger amount of Cs ions into the zeolite crystal structure, owing to its high external surface area. Nanometer-sized zeolite is a promising candidate for the removal of radioactive Cs ions from polluted water. Our QCM study on Cs adsorption uptake behavior provides the information of adsorption kinetics (e.g., adsorption amounts and rates). This technique is applicable to other zeolites, which will be highly valuable for further consideration of radioactive Cs removal in the future. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Evaluation of a process for the decontamination of radioactive hotspots due to activated stellite particles

    International Nuclear Information System (INIS)

    Subramanian, Veena; Chandramohan, Palogi; Chandran, Sinu; Srinivasan, Madapusi P.; Rangarajan, Srinivasan; Velmurugan, Sankaralingam; Narasimhan, Sevilmedu V.

    2011-01-01

    Some of the Indian pressurized heavy water reactors (PHWRs) which use Stellite balls in the ball and screw mechanism of the adjustor rod drive mechanism in the moderator circuit have encountered high radiation fields in the moderator system due to 60 Co. Release of particulate Stellite is responsible for the hotspots in addition to the general uniform contamination of internal surfaces with 60 Co. Extensive laboratory studies have shown that it is possible to dissolve these Stellite particles by adopting a three-step redox process with permanganic acid as the oxidizing agent. These investigations with inactive Stellite in powder form helped to optimize the process conditions. Permanganic acid was found to have the highest dissolution efficiency as compared to alkaline and nitric acid permanganate. The susceptibility of Stellite to corrode or dissolve was found to depend on the concentration of the permanganate, pH and temperature of the process and microstructure of the Stellite alloy. This process was evaluated for its effectiveness on components from nuclear power plants. Component decontamination was carried out on adjustor rod drive assemblies which had 60 Co activity due to Stellite particles with the radiation field ranging from 3 R . h -1 to 20 R . h -1 . They were subjected to decontamination with permanganic acid as the oxidizing agent, followed by citric acid and a solution containing ethylenediaminetetraacetic acid, ascorbic acid and citric acid in a 4:3:3 ratio by weight as the reducing formulation. In the first trial, one adjustor rod drive mechanism was subjected to decontamination. After two cycles of treatment, an average decontamination factor (DF) of 6.8, with a maximum DF of 11.7, was achieved. The same process but with one cycle was repeated on eight more adjustor rod drive mechanisms. 60 Co activity in the range of 13-93 mCi was removed from these adjustor rods. Loose contamination of the order of 30 000-40 000 decays per min and cm 2 observed

  16. Evaluation of a process for the decontamination of radioactive hotspots due to activated stellite particles

    Energy Technology Data Exchange (ETDEWEB)

    Subramanian, Veena; Chandramohan, Palogi; Chandran, Sinu; Srinivasan, Madapusi P.; Rangarajan, Srinivasan; Velmurugan, Sankaralingam; Narasimhan, Sevilmedu V. [BARC Facilities, Kalpakkam, Tamil Nadu (India). Water and Steam Chemistry Div.

    2011-06-15

    Some of the Indian pressurized heavy water reactors (PHWRs) which use Stellite balls in the ball and screw mechanism of the adjustor rod drive mechanism in the moderator circuit have encountered high radiation fields in the moderator system due to {sup 60}Co. Release of particulate Stellite is responsible for the hotspots in addition to the general uniform contamination of internal surfaces with {sup 60}Co. Extensive laboratory studies have shown that it is possible to dissolve these Stellite particles by adopting a three-step redox process with permanganic acid as the oxidizing agent. These investigations with inactive Stellite in powder form helped to optimize the process conditions. Permanganic acid was found to have the highest dissolution efficiency as compared to alkaline and nitric acid permanganate. The susceptibility of Stellite to corrode or dissolve was found to depend on the concentration of the permanganate, pH and temperature of the process and microstructure of the Stellite alloy. This process was evaluated for its effectiveness on components from nuclear power plants. Component decontamination was carried out on adjustor rod drive assemblies which had {sup 60}Co activity due to Stellite particles with the radiation field ranging from 3 R . h{sup -1} to 20 R . h{sup -1}. They were subjected to decontamination with permanganic acid as the oxidizing agent, followed by citric acid and a solution containing ethylenediaminetetraacetic acid, ascorbic acid and citric acid in a 4:3:3 ratio by weight as the reducing formulation. In the first trial, one adjustor rod drive mechanism was subjected to decontamination. After two cycles of treatment, an average decontamination factor (DF) of 6.8, with a maximum DF of 11.7, was achieved. The same process but with one cycle was repeated on eight more adjustor rod drive mechanisms. {sup 60}Co activity in the range of 13-93 mCi was removed from these adjustor rods. Loose contamination of the order of 30 000-40 000

  17. System decontamination as a tool to control radiation fields

    Energy Technology Data Exchange (ETDEWEB)

    Riess, R.; Bertholdt, H.O. [Siemens Power Generation Group, Erlangen (Germany)

    1995-03-01

    Since chemical decontamination of the Reactor Coolant Systems (RCS) and subsystems has the highest potential to reduce radiation fields in a short term this technology has gained an increasing importance. The available decontamination process at Siemens, i.e., the CORD processes, will be described. It is characterized by using permanganic acid for preoxidation and diluted organic acid for the decontamination step. It is a regenerative process resulting in very low waste volumes. This technology has been used frequently in Europe and Japan in both RCS and subsystems. An overview will be given i.e. on the 1993 applications. This overview will include plant, scope, date of performance, system volume specal features of the process removed activities, decon factor time, waste volumes, and personnel dose during decontamination. This overview will be followed by an outlook on future developments in this area.

  18. Statistical sampling method for releasing decontaminated vehicles

    International Nuclear Information System (INIS)

    Lively, J.W.; Ware, J.A.

    1996-01-01

    Earth moving vehicles (e.g., dump trucks, belly dumps) commonly haul radiologically contaminated materials from a site being remediated to a disposal site. Traditionally, each vehicle must be surveyed before being released. The logistical difficulties of implementing the traditional approach on a large scale demand that an alternative be devised. A statistical method (MIL-STD-105E, open-quotes Sampling Procedures and Tables for Inspection by Attributesclose quotes) for assessing product quality from a continuous process was adapted to the vehicle decontamination process. This method produced a sampling scheme that automatically compensates and accommodates fluctuating batch sizes and changing conditions without the need to modify or rectify the sampling scheme in the field. Vehicles are randomly selected (sampled) upon completion of the decontamination process to be surveyed for residual radioactive surface contamination. The frequency of sampling is based on the expected number of vehicles passing through the decontamination process in a given period and the confidence level desired. This process has been successfully used for 1 year at the former uranium mill site in Monticello, Utah (a CERCLA regulated clean-up site). The method forces improvement in the quality of the decontamination process and results in a lower likelihood that vehicles exceeding the surface contamination standards are offered for survey. Implementation of this statistical sampling method on Monticello Projects has resulted in more efficient processing of vehicles through decontamination and radiological release, saved hundreds of hours of processing time, provided a high level of confidence that release limits are met, and improved the radiological cleanliness of vehicles leaving the controlled site

  19. Electrolytic decontamination of the 3013 inner can

    International Nuclear Information System (INIS)

    Wedman, D.E.; Nelson, T.O.; Rivera, Y.; Weisbrod, K.; Martinez, H.E.; Limback, S.

    1998-01-01

    Disposition of plutonium recovered from nuclear weapons or production residues must be stored in a manner that ensures safety. The criteria that has been established to assure the safety of stored materials for a minimum of 50 years is DOE-STD-3013. Los Alamos National Laboratory (LANL) has designed a containment package in accordance with the DOE standard. The package consists of an optional convenience (food pack) can, a welded type 304L stainless steel inner (primary) can, and a welded type 304L stainless steel outer (secondary) can. With or without the food pack can, the material is placed inside the primary can and welded shut under a helium atmosphere. This activity takes place totally within the confinement of the glove box line. Following the welding process, the can is checked for leaks and then sent down the line for decontamination. Once decontaminated, the sealed primary can may be removed from the glove box line. Welding of the secondary container takes place outside the glove box line. The highly automated decontamination process that has been developed to support the packaging of Special Nuclear Materials is based on an electrolytic process similar to the wide spread industrial technique of electropolishing. The can is placed within a specially designed stainless steel fixture built within a partition of a glove box. This fixture is then filled with a flowing electrolyte solution. A low DC electric current is made to flow between the can, acting as the anode, and the fixture, acting as the cathode. Following the decontamination, the system provides a flow of rinse water through the fixture to rinse the can of remaining salt residues. The system then carried out a drying cycle. Finally, the fixture is opened from the opposite side of the partition and the can surface monitored directly and through surface smears to assure that decontamination is adequate

  20. Electrolytic decontamination of the 3013 inner can

    International Nuclear Information System (INIS)

    Wedman, D.E.; Nelson, T.O.; Rivera, Y.; Weisbrod, K.; Martinez, H.E.; Limback, S.

    1998-01-01

    Disposition of plutonium recovered from nuclear weapons or production residues must be stored in a manner that ensures safety. The criteria that has been established to assure the safety of stored materials for a minimum of 50 years is DOE-STD-3013. This standard specifies both the requirements for containment and furthermore specifies that the inner container be decontaminated to a level of ≤20 dpm/100 cm 2 swipable and ≤500 dpm/100 cm 2 direct alpha such that a failure of the outer containment barrier will have a lower probability of resulting in a spread of contamination. The package consists of an optional convenience (food pack) can, a welded type 304L stainless steel inner (primary) can, and a welded type 304L stainless steel outer (secondary) can. Following the welding process, the can is checked for leaks and then sent down the line for decontamination. Once decontaminated, the sealed primary can may be removed from the glove box line. Welding of the secondary container takes place outside the glove box line. The highly automated decontamination process that has been developed to support the packaging of Special Nuclear Materials is based on an electrolytic process similar to the wide spread industrial technique of electropolishing. The can is placed within a specially designed stainless steel fixture built within a partition of a glove box. The passage of current through this electrolytic cell results in a uniform anodic dissolution of the surface metal layers of the can. This process results in a rapid decontamination of the can. The electrolyte is fully recyclable, and the separation of the chromium from the actinides results in a compact, non RCRA secondary waste product

  1. Decontamination Technologies, Task 3, Urban Remediation and Response Project

    International Nuclear Information System (INIS)

    Heiser, J.; Sullivan, T.

    2009-01-01

    decontamination process(es). In the case of an entire building, the value may be obvious; it's costly to replace the structure. For a smaller item such as a vehicle or painting, the cost versus benefit of decontamination needs to be evaluated. This will be determined on a case by case basis and again is beyond the scope of this report, although some thoughts on decontamination of unique, personal and high value items are given. But, this is clearly an area that starting discussions and negotiations early on will greatly benefit both the economics and timeliness of the clean up. In addition, high value assets might benefit from pre-event protection such as protective coatings or HEPA filtered rooms to prevent contaminated outside air from entering the room (e.g., an art museum)

  2. Decontamination Technologies, Task 3, Urban Remediation and Response Project

    Energy Technology Data Exchange (ETDEWEB)

    Heiser,J.; Sullivan, T.

    2009-06-30

    during the decontamination process(es). In the case of an entire building, the value may be obvious; it's costly to replace the structure. For a smaller item such as a vehicle or painting, the cost versus benefit of decontamination needs to be evaluated. This will be determined on a case by case basis and again is beyond the scope of this report, although some thoughts on decontamination of unique, personal and high value items are given. But, this is clearly an area that starting discussions and negotiations early on will greatly benefit both the economics and timeliness of the clean up. In addition, high value assets might benefit from pre-event protection such as protective coatings or HEPA filtered rooms to prevent contaminated outside air from entering the room (e.g., an art museum).

  3. Decontamination of the RA reactor heavy water system, Annex 9

    International Nuclear Information System (INIS)

    Maksimovic, Z.B.; Nikolic, R.M.; Marinkovic, M.D.; Jelic, Lj.M.

    1963-01-01

    Both stainless steel and aluminium parts of the RA reactor heavy water system system were decontaminated as well as the heavy water itself. System was contaminated with 60 Co. Decontamination factor was determined by activity measurements during distillation. Concentration of the corrosion products in the heavy water was measured by spectrochemical analysis, and found to be 0.1 - 1 mg/l. Chemical analyses of the aluminium and stainless steel surfaces showed that cobalt was adsorbed on the aluminium oxide layer. Water solution of 7%H 3 PO 4 + 2% CrO 3 was used for decontamination of the heavy water system and distillation device. This was found to be the most efficient solvent which does not affect stainless steel corrosion. Decontamination factors achieved were from 60 - 100. Decontamination results enabled determining the distribution of cobalt in the system: 10 Ci on the stainless steel parts, 50 Ci in the heavy water; and above 600 Ci on the fuel and experimental channels. Specific activity of 60 Co was calculated to be 15 Ci/g on the reactor channels, 8 Ci/g on the stainless steel parts and 3 Ci/g in the heavy water. Decontamination of the aluminium parts was not done because it was considered it could initiate corrosion. Since the efficiency of distillation is increased it was expected that permanent distillation would remove most of the activity in the reactor channels

  4. Radioactive decontamination apparatus and process

    International Nuclear Information System (INIS)

    Jackson, O.L.

    1983-01-01

    Apparatus for removing radioactive contamination from metal objects is disclosed, consisting of three of three separate pieces. The first is an electro- polishing tank, pump and filter assembly, ventilation duct and filter assembly, and DC power supply. The second is a rinse tank and a pump and filter assembly therefor. The third is a divot crane. The electro-polishing tank assembly and the rinse tank assembly are each separately mounted on pallets to facilitate moving. The filter systems of the electro-polishing tank and the rinse tank are designed to remove the radioactive contamination from the fluids in those tanks. Heavy items or highly contaminated items are handled with the divot crane constructed of stainless steel. The electro- polishing tank and the rinse tank are also made of stainless steel. The ventilation system on the electro- polishing tank exhausts acid fumes resulting from the tank heaters and the electro-polishing process. Inside the electro-polishing tank are two swinging arms that carry two stainless steel probes that hang down in the electrolyte fluid. These negative DC probes and are electrically isolated from the tank and the rest of the system. Across the top center of the tank is a copper pipe, which is also electrically isolated from the tank. This is the positive side of the DC system. To decontaminate a metal object, it is suspended from the positive copper pipe, with good electrical contact, into the electrolyte fluid. The negative probes are then moved on their swinging arms to a close proximity to the object being decontaminated, without making contact

  5. Electrodialytic decontamination of spent ion exchange resins

    International Nuclear Information System (INIS)

    Nott, B.R.

    1982-01-01

    Development of a novel electrodialytic decontamination process for the selective removal of radioactive Cs from spent ion exchange resins containing large amounts of Li is described. The process involves passage of a dc electric current through a bed of the spent ion exchange resin in a specially designed electrodialytic cell. The radiocesium so removed from a volume of the spent resin is concentrated onto a much smaller volume of a Cs selective sorbent to achieve a significant radioactive waste volume reduction. Technical feasibility of the electrodialytic resin decontamination process has been demonstrated on a bench scale with a batch of simulated spent ion exchange resin and using potassium cobalt ferrocyanide as the Cs selective sorbent. A volume reduction factor between 10 and 17 has been estimated. The process appears to be economically attractive. Improvements in process economics can be expected from optimization of the process. Other possible applications of the EDRD process have been identified

  6. Room source management decontamination in Uruguay

    International Nuclear Information System (INIS)

    Blanco, D.; Montanez, Osvaldo

    1998-01-01

    A surface,work materials and tools contamination it produced for Ra-226 sources management in des use in Uruguayan radioactive waste and sources management and storage room specifically in the Uruguay Republic University in Nuclear Search Center. A surface contamination direct was performed measurement with Eberline alpha particles Contamat FHT 111M with 42 496/30 sounder. It found greater and least contamination grade in all cement floor as well as in tables where was managed with Ra-226 sources. A value measured surface contamination can see in the Room scheme with more 200 Bq/cm in extension small places. A segregation between work materials and tools considerate d free contamination was realized. The contaminated objects was separated for a future treatment. A proceeding followed in the decontamination was inhale, abrasion,sweep essays in different representative zones, obtain decontamination factors and residual activity

  7. Surface decontamination by heterogeneous foams and suspensions

    International Nuclear Information System (INIS)

    Polyakov, A.; Poluektov, P.; Emets, E.; Kuchumov, V.; Rybakov, K.; Teterin, E.

    2000-01-01

    A variety of methods was used to investigate the surface of stainless steel as delivered or treated (electrochemically polished, machine ground). Micro X-ray spectral analysis evidenced a uniform distribution of alloying elements. Auger spectroscopy revealed the layer-by-layer composition by elements and the thickness of the superficial oxide film. The distribution of heterogeneous uranium dioxide powders on the stainless steel surface was examined by microprobe analysis (using Comebax). In the order of increasing contamination by uranium dioxide, the surfaces can be arranged as: untreated - polished - ground. The behaviour of hydrogen peroxide in alkaline solutions was studied by spectrophotometry and laser analysis. Decontamination of stainless steel surfaces from UO 2 by microgaseous emulsions in alkaline media with surfactants present was tested. The decontamination factor was determined as a function of the size and volume of gas bubbles. It was shown to rise with increasing gas content. (author)

  8. Chemical decontamination method in nuclear facility system

    International Nuclear Information System (INIS)

    Takahashi, Ryota; Sakai, Hitoshi; Oka, Shigehiro.

    1996-01-01

    Pumps and valves in a closed recycling loop system incorporating materials to be chemically decontaminated are decomposed, a guide plate having the decomposed parts as an exit/inlet of a decontaminating liquid is formed, and a decontaminating liquid recycling loop comprising a recycling pump and a heater is connected to the guide plate. Decontaminating liquid from a decontaminating liquid storage tank is supplied to the decontaminating liquid recycling loop. With such constitutions, the decontaminating liquid is filled in the recycling closed loop system incorporating materials to be decontaminated, and the materials to be decontaminated are chemically decontaminated. The decontaminating liquid after the decontamination is discharged and flows, if necessary, in a recycling system channel for repeating supply and discharge. After the decontamination, the guide plate is removed and returned to the original recycling loop. When pipelines of a reactor recycling system are decontaminated, the amount of decontaminations can be decreased, and reforming construction for assembling the recycling loop again, which requires cutting for pipelines in the system is no more necessary. Accordingly, the amount of wastes can be decreased, and therefore, the decontamination operation is facilitated and radiation dose can be reduced. (T.M.)

  9. Modification of the Decontamination Facility at the Kruemmel NPP - 13451

    Energy Technology Data Exchange (ETDEWEB)

    Klute, Stefan; Kupke, Peter [Siempelkamp Nukleartechnik GmbH Am Taubenfeld 25/1, 69123 Heidelberg (Germany)

    2013-07-01

    In February 2009, Siempelkamp Nukleartechnik GmbH was awarded the contract for the design, manufacture, delivery and construction of a new Decontamination Facility in the controlled area for Kruemmel NPP. The new decontamination equipment has been installed according to the state of art of Kruemmel NPP. The existing space required the following modification, retrofitting and reconstruction works: - Demounting of the existing installation: to create space for the new facility it was necessary to dismantle the old facility. The concrete walls and ceilings were cut into sizes of no more than 400 kg for ease of handling. This enabled decontamination so largest possible amount could be released for recycling. All steel parts were cut into sizes fitting for iron-barred boxes, respecting the requirement to render the parts decontaminable and releasable. - Reconstructing a decontamination facility: Reconstruction of a decontamination box with separate air lock as access area for the decontamination of components and assemblies was conducted using pressurized air with abrasives (glass beads or steel shots). The walls were equipped with sound protection, the inner walls were welded gap-free to prevent the emergence of interstices and were equipped with changeable wear and tear curtains. Abrasive processing unit positioned underneath the dry blasting box adjacent to the two discharge hoppers. A switch has been installed for the separation of the glass beads and the steel shot. The glass beads are directed into a 200 l drum for the disposal. The steel shot was cleaned using a separator. The cleaned steel shot was routed via transportation devices to the storage container, making it available for further blasting operations. A decontamination box with separate air lock as access area for the decontamination of components and assemblies using high pressure water technology was provided by new construction. Water pressures between 160 bar and 800 bar can be selected. The inner

  10. Modification of the Decontamination Facility at the Kruemmel NPP - 13451

    International Nuclear Information System (INIS)

    Klute, Stefan; Kupke, Peter

    2013-01-01

    In February 2009, Siempelkamp Nukleartechnik GmbH was awarded the contract for the design, manufacture, delivery and construction of a new Decontamination Facility in the controlled area for Kruemmel NPP. The new decontamination equipment has been installed according to the state of art of Kruemmel NPP. The existing space required the following modification, retrofitting and reconstruction works: - Demounting of the existing installation: to create space for the new facility it was necessary to dismantle the old facility. The concrete walls and ceilings were cut into sizes of no more than 400 kg for ease of handling. This enabled decontamination so largest possible amount could be released for recycling. All steel parts were cut into sizes fitting for iron-barred boxes, respecting the requirement to render the parts decontaminable and releasable. - Reconstructing a decontamination facility: Reconstruction of a decontamination box with separate air lock as access area for the decontamination of components and assemblies was conducted using pressurized air with abrasives (glass beads or steel shots). The walls were equipped with sound protection, the inner walls were welded gap-free to prevent the emergence of interstices and were equipped with changeable wear and tear curtains. Abrasive processing unit positioned underneath the dry blasting box adjacent to the two discharge hoppers. A switch has been installed for the separation of the glass beads and the steel shot. The glass beads are directed into a 200 l drum for the disposal. The steel shot was cleaned using a separator. The cleaned steel shot was routed via transportation devices to the storage container, making it available for further blasting operations. A decontamination box with separate air lock as access area for the decontamination of components and assemblies using high pressure water technology was provided by new construction. Water pressures between 160 bar and 800 bar can be selected. The inner

  11. Decontamination processes for waste glass canisters

    International Nuclear Information System (INIS)

    Rankin, W.N.

    1982-01-01

    A Defense Waste Processing Facility (DWPF) is currently being designed to convert Savannah River Plant liquid, high-level radioactive waste into a solid form, such as borosilicate glass. To prevent the spread of radioactivity, the outside of the canisters of waste glass must have very low levels of smearable radioactive contamination before they are removed from the DWPF. Several techniques were considered for canister decontamination: high-pressure water spray, electropolishing, chemical dissolution, and abrasive blasting. An abrasive blasting technique using a glass frit slurry has been selected for use in the DWPF. No additional equipment is needed to process waste generated from decontamination. Frit used as the abrasive will be mixed with the waste and fed to the glass melter. In contrast, chemical and electrochemical techniques require more space in the DWPF, and produce large amounts of contaminated by-products, which are difficult to immobilize by vitrification

  12. Decontamination by water jet, chemical and electrochemical methods

    International Nuclear Information System (INIS)

    Gauchon, J.P.; Mordenti, P.; Bezia, C.; Fuentes, P.; Kervegant, Y.; Munoz, C.; Pierlas, C.

    1986-01-01

    The decontamination tests have been carried out on samples coming from representative specimens from primary circuit of the PWR and on samples coming from the emergency feed water piping of the German BWR (Isar). The oxide found in PWR primary loops can only be removed by a two steps process. The initial embrittling step is particularly effective in hot alkaline permanganate medium. Oxidation by ozone treatment is less effective. The second step involves chemical erosion of the metal in nitrofluoric acid in conjonction with ultrasonic agitation. Among the reagents used, only oxalic acid is suitable for electrolytic decontamination. Among the reagents possible for decontamination of the Isar specimens (ferritic steel lined with hematite) halogenous acid in mixture without or with oxygenated water, sulfuric acid, the formic acid/formaldehyde mixture are chosen. Metal erosion with high pressure jet as well as the decontamination efficiency on parts lined with hematite have made possible to determine the best conditions. 33 figs, 29 refs

  13. Road surface washing system for decontaminating radioactive substances. Experiment of radioactive decontamination

    International Nuclear Information System (INIS)

    Endo, Mitsuru; Endo, Mai; Kakizaki, Takao

    2015-01-01

    The Great East Japan Earthquake that occurred on March 11, 2011 resulted in the explosion of the TEPCO Fukushima 1st Nuclear Power Plant and the global dispersion of a large quantity of radioactive substances. A high radiation dose was particularly recorded in Fukushima prefecture several weeks after the accident, although the level is presently sufficiently low. However, considering that the adverse effects of low but extended exposure to radiation are yet to be negated, there is the urgent need for further decontamination. In our study, we focused on the efficient decontamination of radioactive substances in residential areas, for which we propose a high-pressure water jet system for washing road surfaces. The system differs from conventional systems of its type that were initially designed for use in the immediate environment of the nuclear reactors of the TEPCO Fukushima 1st Nuclear Power Plant. The proposed system consists of multiple washing, transporter, and server robots. The washing robots decontaminate the road surface using high-pressure water jets and are transported between washed and unwashed areas by the transporter robots. The server robots supply the water used for washing and absorb the polluted water together with ground dust. In this paper, we describe the concept of the system and present the results of decontamination experiments. Particular attention is given to the washing robot and its mechanism and control method. The results of the integration of the washing robot in an experimental system confirmed the feasibility of the proposed system. (author)

  14. Decontamination of some urban surfaces

    International Nuclear Information System (INIS)

    Thornton, E.W.

    1988-04-01

    The long-term consequences of external radiation dose to the public could be a cause for concern in the event of a severe accident at a nuclear power plant leading to the release of fission products to the atmosphere and subsequent contamination of buildings, roads and other components of the urban environment. This study has concentrated on the decontamination of building materials contaminated under wet conditions with soluble, ionic radiocaesium. Results are given on the decontamination of building materials contaminated without run-off, on the effects of waiting between contamination and decontamination and on the effect of pre-treatment with an ammonium salt solution. (author)

  15. Nova target chamber decontamination study

    International Nuclear Information System (INIS)

    1979-05-01

    An engineering study was performed to determine the most effective method for decontamination of the Nova target chamber. Manual and remote decontamination methods currently being used were surveyed. In addition, a concept that may not require in-situ decontamination was investigated. Based on the presently available information concerning material and system compatibility and particle penetration, it is recommended that a system of removable aluminum shields be considered. It is also recommended that a series of tests be performed to more precisely determine the vacuum compatibility and penetrability of other materials discussed in this report

  16. Skin decontamination: principles and perspectives.

    Science.gov (United States)

    Chan, Heidi P; Zhai, Hongbo; Hui, Xiaoying; Maibach, Howard I

    2013-11-01

    Skin decontamination is the primary intervention needed in chemical, biological and radiological exposures, involving immediate removal of the contaminant from the skin performed in the most efficient way. The most readily available decontamination system on a practical basis is washing with soap and water or water only. Timely use of flushing with copious amounts of water may physically remove the contaminant. However, this traditional method may not be completely effective, and contaminants left on the skin after traditional washing procedures can have toxic consequences. This article focuses on the principles and practices of skin decontamination.

  17. Organic decontamination by ion exchange

    International Nuclear Information System (INIS)

    Wilson, T.R.

    1994-01-01

    This study has successfully identified ion exchanger media suitable for decontaminating the 5500-gallon organic layer in Tank 241-C-103. Decontamination of radionuclides is necessary to meet shipping, incinerator site storage, and incineration feed requirements. The exchanger media were identified through a literature search and experiments at the Russian Institute for Physical Chemistry. The principal radionuclides addressed are Cs-137 and Sr-90. Recommendations for an experimental program plan conclude the discussion. The experimental program would provide the data necessary for plant design specifications for a column and for ion exchange media to be used in decontaminating the organic layer

  18. Decontamination and coating of lead

    International Nuclear Information System (INIS)

    Rankin, W.N.; Bush, S.P.; Lyon, C.E.; Walker, V.

    1988-01-01

    Technology is being developed to decontaminate lead used in shielding applications in contaminated environments for recycle as shieldings. Technology is also being developed to coat either decontaminated lead or new lead before it is used in contaminated environments. The surface of the coating is expected to be much easier to decontaminate than the original lead surface. If contamination becomes severely embedded in the coating and cannot be removed, it can be easily cut with a knife and removed from the lead. The used coating can be disposed of as radioactive (hot hazardous) waste. The lead can then be recoated for further use as a shielding material

  19. Magnetite Dissolution Performance of HYBRID-II Decontamination Process

    International Nuclear Information System (INIS)

    Kim, Seonbyeong; Lee, Woosung; Won, Huijun; Moon, Jeikwon; Choi, Wangkyu

    2014-01-01

    In this study, we conducted the magnetite dissolution performance test of HYBRID-II (Hydrazine Based Reductive metal Ion Decontamination with sulfuric acid) as a part of decontamination process development. Decontamination performance of HYBRID process was successfully tested with the results of the acceptable decontamination factor (DF) in the previous study. While following-up studies such as the decomposition of the post-decontamination HYBRID solution and corrosion compatibility on the substrate metals of the target reactor coolant system have been continued, we also seek for an alternate version of HYBRID process suitable especially for decommissioning. Inspired by the relationship between the radius of reacting ion and the reactivity, we replaced the nitrate ion in HYBRID with bigger sulfate ion to accommodate the dissolution reaction and named HYBRID-II process. As a preliminary step for the decontamination performance, we tested the magnetite dissolution performance of developing HYBRID-II process and compared the results with those of HYBRID process. HYBRID process developed previously is known have the acceptable decontamination performance, but the relatively larger volume of secondary waste induced by anion exchange resin to treat nitrate ion is the one of the problems related in the development of HYBRID process to be applicable. Therefore we alternatively devised HYBRID-II process using sulfuric acid and tested its dissolution of magnetite in numerous conditions. From the results shown in this study, we can conclude that HYBRID-II process improves the decontamination performance and potentially reduces the volume of secondary waste. Rigorous tests with metal oxide coupons obtained from reactor coolant system will be followed to prove the robustness of HYBRID-II process in the future

  20. Decontamination of process equipment using recyclable chelating solvent

    International Nuclear Information System (INIS)

    Jevec, J.; Lenore, C.; Ulbricht, S.

    1995-01-01

    The Department of Energy (DOE) is now faced with the task of meeting decontamination and decommissioning obligations at numerous facilities by the year 2019. Due to the tremendous volume of material involved, innovative decontamination technologies are being sought that can reduce the volumes of contaminated waste materials and secondary wastes requiring disposal. With sufficient decontamination, some of the material from DOE facilities could be released as scrap into the commercial sector for recycle, thereby reducing the volume of radioactive waste requiring disposal. Although recycling may initially prove to be more costly than current disposal practices, rapidly increasing disposal costs are expected to make recycling more and more cost effective. Additionally, recycling is now perceived as the ethical choice in a world where the consequences of replacing resources and throwing away reusable materials are impacting the well-being of the environment. Current approaches to the decontamination of metals most often involve one of four basic process types: (1) chemical, (2) manual and mechanical, (3) electrochemical, and (4) ultrasonic. open-quotes Hardclose quotes chemical decontamination solutions, capable of achieving decontamination factors (Df's) of 50 to 100, generally involve reagent concentrations in excess of 5%, tend to physically degrade the surface treated, and generate relatively large volumes of secondary waste. open-quotes Softclose quotes chemical decontamination solutions, capable of achieving Df's of 5 to 10, normally consist of reagents at concentrations of 0.1 to 1%, generally leave treated surfaces in a usable condition, and generate relatively low secondary waste volumes. Under contract to the Department of Energy, the Babcock ampersand Wilcox Company is developing a chemical decontamination process using chelating agents to remove uranium compounds and other actinide species from process equipment

  1. Application of Ultrasonic for Decontamination of Contaminated Soil - 13142

    International Nuclear Information System (INIS)

    Vasilyev, A.P.; Lebedev, N.M.; Savkin, A.E.

    2013-01-01

    The trials of soil decontamination were carried out with the help of a pilot ultrasonic installation in different modes. The installation included a decontamination bath equipped with ultrasonic sources, a precipitator for solution purification from small particles (less than 80 micrometer), sorption filter for solution purification from radionuclides washing out from soil, a tank for decontamination solution, a pump for decontamination solution supply. The trials were carried out on artificially contaminated sand with specific activity of 4.5 10 5 Bk/kg and really contaminated soil from Russian Scientific Center 'Kurchatovsky Institute' (RSC'KI') with specific activity of 2.9 10 4 Bk/kg. It was established that application of ultrasonic intensify the process of soil reagent decontamination and increase its efficiency. The decontamination factor for the artificially contaminated soil was ∼200 and for soil from RSC'KI' ∼30. The flow-sheet diagram has been developed for the new installation as well as determined the main technological characteristics of the equipment. (authors)

  2. Application of Ultrasonic for Decontamination of Contaminated Soil - 13142

    Energy Technology Data Exchange (ETDEWEB)

    Vasilyev, A.P. [JRC ' NIKIET' , Moscow (Russian Federation); Lebedev, N.M. [LLC ' Aleksandra-Plus' , Vologda (Russian Federation); Savkin, A.E. [SUE SIA ' Radon' , Moscow (Russian Federation)

    2013-07-01

    The trials of soil decontamination were carried out with the help of a pilot ultrasonic installation in different modes. The installation included a decontamination bath equipped with ultrasonic sources, a precipitator for solution purification from small particles (less than 80 micrometer), sorption filter for solution purification from radionuclides washing out from soil, a tank for decontamination solution, a pump for decontamination solution supply. The trials were carried out on artificially contaminated sand with specific activity of 4.5 10{sup 5} Bk/kg and really contaminated soil from Russian Scientific Center 'Kurchatovsky Institute' (RSC'KI') with specific activity of 2.9 10{sup 4} Bk/kg. It was established that application of ultrasonic intensify the process of soil reagent decontamination and increase its efficiency. The decontamination factor for the artificially contaminated soil was ∼200 and for soil from RSC'KI' ∼30. The flow-sheet diagram has been developed for the new installation as well as determined the main technological characteristics of the equipment. (authors)

  3. The costs and effectiveness of various decontamination procedures

    International Nuclear Information System (INIS)

    Robinson, C.A.; Haywood, S.M.; Brown, J.

    1991-01-01

    Knowledge of the cost and effectiveness of decontamination techniques is necessary to optimise the implementation of this countermeasure. These factors vary depending upon the nature of the land affected. There is a great deal of data available on the cost and efficacy of specific decontamination techniques on particular surfaces, but little information for combinations of techniques in real environments. This paper describes the preliminary stages of a project, in progress at the National Radiological Protection Board (NRPB), aimed at providing this information, for inner city, residential and rural areas. The efficacies of individual decontamination processes on specific surfaces were from the available literature. The NRPB EXPURT (EXPosure from Urban Radionuclide Transfer) compartmental model was used to determine the effectiveness of a number of representative decontamination programmes; each programme represents a combination of common decontamination techniques which may be applied to the various surfaces comprising an inner-city, residential or rural environment, ie, paving, walls, roofs and soil. The effectiveness of each programme was measured in terms of the reduction in dose, or dose rate, to an individual in that environment, taking account of the building characteristics, and the occupancy of the population in these buildings. The costs of each programme were derived, based on data available in current literature on the cost of the constituent decontamination techniques. Representative cost and effectiveness data are presented and their application is discussed

  4. Decontamination of surfaces (1961)

    International Nuclear Information System (INIS)

    Mestre, E.

    1961-01-01

    The continued expansion of atomic Energy has led the S.C.R.G.R. to extend simultaneously the recovery of materials contaminated by use in radio-active media. The importance of this aspect of atomic Energy was not immediately obvious to those concerned but is now fully recognized due to the cost of the materials and installations, and also to the time required for the construction of special equipment for the C.E.A. Another very important reason is the dangers associated with the handling of contaminated material. The S.C.R.G.R. attacked this problem from the point of view of these dangers. It later became apparent to the users, once the decontamination methods had proved their worth, that the process presented advantages from the material and cost-saving point of view. (author) [fr

  5. Ultrasonic decontamination robot

    International Nuclear Information System (INIS)

    Patenaude, R.S.

    1984-01-01

    An ultrasonic decontamination robot removes radioactive contamination from the internal surface of the inlet and outlet headers, divider plate, tube sheet, and lower portions of tubes of a nuclear power plant steam generator. A programmable microprocessor controller guides the movement of a robotic arm mounted in the header manway. An ultrasonic transducer having a solvent delivery subsystem through which ultrasonic action is achieved is moved by the arm over the surfaces. A solvent recovery suction tube is positioned within the header to remove solvent therefrom while avoiding interference with the main robotic arm. The solvent composition, temperature, pressure, viscosity, and purity are controlled to optimize the ultrasonic scrubbing action. The ultrasonic transducer is controlled at a power density, frequency, and on-off mode cycle such as to optimize scrubbing action within the range of transducer-to-surface distance and solvent layer thickness selected for the particular conditions encountered. Both solvent and transducer control actions are optimized by the programmable microprocessor. (author)

  6. Decontamination & decommissioning focus area

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    In January 1994, the US Department of Energy Office of Environmental Management (DOE EM) formally introduced its new approach to managing DOE`s environmental research and technology development activities. The goal of the new approach is to conduct research and development in critical areas of interest to DOE, utilizing the best talent in the Department and in the national science community. To facilitate this solutions-oriented approach, the Office of Science and Technology (EM-50, formerly the Office of Technology Development) formed five Focus AReas to stimulate the required basic research, development, and demonstration efforts to seek new, innovative cleanup methods. In February 1995, EM-50 selected the DOE Morgantown Energy Technology Center (METC) to lead implementation of one of these Focus Areas: the Decontamination and Decommissioning (D & D) Focus Area.

  7. Oxidative Tritium Decontamination System

    International Nuclear Information System (INIS)

    Gentile, Charles A.; Parker, John J.; Guttadora, Gregory L.; Ciebiera, Lloyd P.

    2002-01-01

    The Princeton Plasma Physics Laboratory, Tritium Systems Group has developed and fabricated an Oxidative Tritium Decontamination System (OTDS), which is designed to reduce tritium surface contamination on various components and items. The system is configured to introduce gaseous ozone into a reaction chamber containing tritiated items that require a reduction in tritium surface contamination. Tritium surface contamination (on components and items in the reaction chamber) is removed by chemically reacting elemental tritium to tritium oxide via oxidation, while purging the reaction chamber effluent to a gas holding tank or negative pressure HVAC system. Implementing specific concentrations of ozone along with catalytic parameters, the system is able to significantly reduce surface tritium contamination on an assortment of expendable and non-expendable items. This paper will present the results of various experimentation involving employment of this system

  8. Decontamination of organic waste

    International Nuclear Information System (INIS)

    Schulz, W.

    1977-01-01

    Decontamination stands for the sack collecting of wc-waste water of nuclear-medical tracts and especially the collecting of primary urine and primary faeces of patients after application of radio-isotopes (e.g. iodine 131). They are tied up in the sacks, treated with antiseptic and decomposition-preventing agents, and finally stored in a decupation depot over the time constant. The decupation depot can, for example, be a deep-freezor with separations and clocks, which is radiation-isolated. After the time constant a chemical and/or physical destruction (e.g. comminution) takes place, with simultaneous disinfection and thawing (vapour heating) and the transfer to the canalization. (DG) [de

  9. SRP decontamination and decommissioning scoping study

    International Nuclear Information System (INIS)

    Martin, W.P.

    1986-06-01

    Of the approximately 3000 site facilities, 496 were judged to be radioactively contaminated thereby requiring Decontamination and Decommissioning (D and D) after shutdown. To enable projection of D and D timing for each of the 496 facilities, a plant shutdown schedule was developed. A 5-year ''cool-down'' period was added to the highly contaminated facilities to allow radioactive decay resulting in a reduction of cost, waste volume, and radiation exposure. D and D of all facilities is projected to be completed in FY 2045. Since essentially all of the plant facilities are scheduled to operate past FY 2000, only seventy-four of the 496 facilities are projected to be decommissioned prior to FY 2000. These facilities include currently excessed facilities and those scheduled for shutdown in the near future - seepage basins, HWCTR, R-Reactor, high level waste tanks, etc. The type of D and D chosen is the factor having the most significant effect on D and D costs and waste volumes. The two types of final D and D are Entombment and Dismantlement. Dismantlement can increase costs and waste volumes by a factor of 2 to 100 compared to Entombment. This point should be kept in mind when reviewing this scoping study as approximately 75% of the projects are estimated based upon the less costly Entombment option. The D and D estimates for the 496 facilities are summarized by plant area in Table 3 and by custodian group (Program/General Department) in Table 4. The total estimated D and D cost in constant FY 1986 dollars is approximately $800,000,000, with total solid waste volumes of 5,000,000 and 170,000 cubic feet, for low level waste (LLW) and transuranic waste (TRU), respectively. A 6% annual escalation factor increases the total project costs of 800,000,000, FY 1986 dollars to 7 billion dollars. 27 refs

  10. Agricultural soils decontamination techniques: methods and results of tests realized near Chernobyl

    International Nuclear Information System (INIS)

    Maubert, H.; Jouve, A.; Mary, N.

    1992-01-01

    After a major nuclear accident, decontamination of agricultural soils would be necessary in order to reclaim the land. Specific techniques were studied in the framework of the European program for Rehabilitation of Soils and Surfaces after an Accident (RESSAC). Different ways to remove the top layer of soils are described, and especially the use of Decontaminating Vegetal Network (D.V.N.) combined with spraying of organic polymers. Real scale tests in the 30 km zone around the Chernobyl nuclear power plant showed that it is possible to achieve an excellent decontamination of agricultural fields (decontamination factor greater than 95%. (author)

  11. Decontamination of Stainless Steel SS 304 Type with Pressurized CO2 Solid

    International Nuclear Information System (INIS)

    Sutoto

    2007-01-01

    The abrasive decontamination of the stainless steel valve using 12 bar pressurized CO 2 solid has been done. Experiment activities was performed in the HOT CELL facility with variation of blasting time 15, 30, 45 and 60 seconds. The result of experiment shown that the operation of abrasive decontamination during 45 seconds gives the decreasing of the equipment radiation dose rate from 460 to 200 mRem/h and decontamination factor 1.35. The secondary waste from decontamination activities was treated by filtration method using HEPA filter and activated carbon filter. (author)

  12. Decontamination of a canyon crane at the Savannah River Plant

    International Nuclear Information System (INIS)

    Stevenson, D.A.; Moore, D.B.; Bowers, J.W.; Brown, D.L.

    1985-01-01

    Decontamination of the crane is reviewed in terms of the health physics aspects, controls during decontamination efforts, and the resultant radiation exposure rates for decontamination efforts. 17 figs.,

  13. Decontamination strategies in contaminated settlement

    International Nuclear Information System (INIS)

    Hubert, P.; Jouve, A.; Tallec, V. Le

    1996-01-01

    Six years after the Chernobyl accident, decontamination actions had been completed in many places, the contamination could be considered as fixed, especially on urban surfaces and the social situation was felt to be stabilized. Under those conditions the efficiency of the 'classical' decontamination techniques was under question, it was worthwhile to look at new specific techniques. Besides it was necessary to discuss the interest of new decontamination actions in settlements. The European Union (EU) sponsored a project ECP 4 in order to look at the opportunities for further dose reduction actions in the contaminated territories of the three republics affected by the accident. The objective was to provide a local decision maker, faced with many alternatives for decontamination, with all the elements for determining what to do according to the various objectives he might pursue. The main results are presented here. (author)

  14. Contamination and decontamination of skin

    International Nuclear Information System (INIS)

    Severa, J.; Knajfl, J.

    1983-01-01

    In external contamination the beta radiation dose is the prevalent component of the total dose absorbed by the skin. There exist four types of radionUclide bonds to the skin: mechanical retention of solid particles or solution on the surface and in the pores, physical adsorption of nondissociated molecules or colloids, the ion exchange effect, and chemisorption. Radionuclides then penetrate the skin by transfollicular transfer. The total amount of radioactive substances absorbed into the skin depends on the condition of the skin. Skin is decontaminated by washing with lukewarm water and soap or with special decontamination solutions. The most widely used components of decontamination solutions are detergents, chelaton, sodium hexametaphosphate, oxalic acid, citric acid. The main principles of the decontamination of persons are given. (M.D.)

  15. BR-5 primary circuit decontamination

    International Nuclear Information System (INIS)

    Efimov, I.A.; Nikulin, M.P.; Smirnov-Averin, A.P.; Tymosh, B.S.; Shereshkov, V.S.

    1976-01-01

    Results and methodology of steam-water and acid decontamination of the primary coolant circuit SBR-5 reactor in 1971 are discussed. Regeneration process in a cold trap of the primary coolant circuit is discussed

  16. Decontaminating method for radioactive contaminant

    International Nuclear Information System (INIS)

    Suzuki, Ken-ichi.

    1994-01-01

    After decontamination of radioactive contaminates with d-limonene, a radioactive material separating agent not compatible with liquid wastes caused by decontamination is added to the liquid wastes. Then after stirring, they are stood still to be separated into two phases, and the radioactive materials in the liquid waste phase caused by decontamination are transferred to the phase of the radioactive material separating agent. With such procedures, they can satisfactorily be separated into two phases of d-limonene and the radioactive material separating agent. Further, d-limonene remaining after the separation can be used again as a decontaminating agent for radioactive contaminates. Therefore, the amount of d-limonene to be used can be reduced, to lower the cost for cleaning, thereby enabling to reduce the amount of radioactive wastes formed. (T.M.)

  17. Evaluation of commercially available decontamination chemicals

    International Nuclear Information System (INIS)

    Shurte, E.A.; Rankin, W.N.

    1988-01-01

    The effectiveness of commercially available decontamination solutions was compared with the effectiveness of 10% oxalic acid in controlled laboratory tests. Type 304L stainless steel and Inconel 625 specimens were used. Contamination was sludge from Savannah River Plant (SRP) high level waste tanks. Measured amounts of contamination were placed on each specimen. They were then heated to bond the contamination to the surface and cleaned according to the manufacturer's directions. The effectiveness of the product was determined by monitoring specimens before and after cleaning. Four of the 16 solutions evaluated removed all the contamination from Type 304L stainless steel. Inconel 625 was more difficult to decontaminate. Further tests are planned with the chemicals that were most effective in this test. 4 refs., 6 tabs

  18. [Decontamination of organophosphorus compounds: Towards new alternatives].

    Science.gov (United States)

    Poirier, L; Jacquet, P; Elias, M; Daudé, D; Chabrière, E

    2017-05-01

    Organophosphorus coumpounds (OP) are toxic chemicals mainly used for agricultural purpose such as insecticides and were also developed and used as warfare nerve agents. OP are inhibitors of acetylcholinesterase, a key enzyme involved in the regulation of the central nervous system. Chemical, physical and biological approaches have been considered to decontaminate OP. This review summarizes the current and emerging strategies that are investigated to tackle this issue with a special emphasis on enzymatic remediation methods. During the last decade, many studies have been dedicated to the development of biocatalysts for OP removal. Among these, recent reports have pointed out the promising enzyme SsoPox isolated from the archaea Sulfolobus solfataricus. Considering both its intrinsic stability and activity, this hyperthermostable enzyme is highly appealing for the decontamination of OP. Copyright © 2017 Académie Nationale de Pharmacie. All rights reserved.

  19. Bacterial decontamination using ambient pressure nonthermal discharges

    Energy Technology Data Exchange (ETDEWEB)

    Birmingham, J.G.; Hammerstrom, D.J.

    2000-02-01

    Atmospheric pressure nonthermal plasmas can efficiently deactivate bacteria in gases, liquids, and on surfaces, as well as can decompose hazardous chemicals. This paper focuses on the changes to bacterial spores and toxic biochemical compounds, such as mycotoxins, after their treatment in ambient pressure discharges. The ability of nonthermal plasmas to decompose toxic chemicals and deactivate hazardous biological materials has been applied to sterilizing medical instruments, ozonating water, and purifying air. In addition, the fast lysis of bacterial spores and other cells has led us to include plasma devices within pathogen detection instruments, where nucleic acids must be accessed. Decontaminating chemical and biological warfare materials from large, high value targets such as building surfaces, after a terrorist attack, are especially challenging. A large area plasma decontamination technology is described.

  20. Evaluation of commercially available decontamination chemicals

    International Nuclear Information System (INIS)

    Shurte, E.A.

    1988-01-01

    The effectiveness of commercially available decontamination solutions was compared with the effectiveness of 10% oxalic acid in controlled lab. tests. Type 304L stainless steel and Inconel 625 specimens were used. Contamination was sludge from Savannah River Plant (SRP) high level waste tanks. Measured amounts of contamination were placed on each specimen. They were then heated to bond the contamination to the surface and cleaned according to the manufacturer's directions. The effectiveness of the produce was determined by monitoring specimens before and after cleaning. Four of the 16 solutions evaluated removed all the contamination from Type 304L stainless steel. Inconel 625 was more difficult to decontaminate. Further tests are planned with the chemicals that were most effective in this test

  1. Use of laser ablation in nuclear decontamination

    International Nuclear Information System (INIS)

    Moggia, Fabrice; Lecardonnel, Xavier; Damerval, Frederique

    2012-09-01

    The development and the use of clean decontamination process appear to be one of the main priorities for industries especially for nuclear industries. This is especially due to the fact of wastes minimization which is one of the principal commitments. One answer would be to use a photonic process such as the LASER process. The principle of this process is based on the absorption, by the contaminant, of the photon's energy. This energy then will propagate into the material and create some mechanical waves responsible of the interfaces embrittlement and de-cohesion. As we can see, this process so called LASER ablation does not use any chemicals and allows us to avoid any production of liquid waste. Since now a couple of years, the Clean-Up Business Unit of AREVA group (BE/CL) investigates this new decontamination technology. Many tests have been done in inactive conditions on various simulants such as paints, inks, resins, metallic oxides firstly in order to estimate its efficiency but also to fully qualify it. After that, we decided to move on hot tests to fully validate this new process and to show its interest for the nuclear industry. Those hot tests have been done on two kinds of contaminated material (on tank pieces covered with a thick metallic oxide layer and on metallic pieces covered with grease). Some information such as Scanning Electron Microscopy (SEM), X-Ray scattering spectroscopy and decontamination factors (DF) will be provided in this paper. (authors)

  2. Improvement of solvents for chemical decontamination: nickel ferrites removal

    International Nuclear Information System (INIS)

    Figueroa, Carlos A.; Morando, Pedro J.; Blesa, Miguel A.

    1999-01-01

    Carboxylic acids are usually included in commercial solvents for the chemical cleaning and decontamination of metal surfaces from the oxide layers grown and/or deposited from high temperature water by corrosive process. In particular oxalic acid is included in second path of AP-Citrox method. However, in some cases, their use shows low efficiency. This fact is attributed to the special passivity of the mixed oxides as nickel ferrites. This work reports a kinetic study of dissolution of a synthetic nickel ferrite (NiFe 2 O 4 ) confronted with simple oxides (NiO and Fe 2 O 3 ) in mineral acids and oxalic acid. The dissolution factor and reaction rate were determined in several conditions (reactive concentrations, pH and added ferrous ions). Experimental data of dissolution (with and without Fe(II) added) show a congruent kinetic regime. Pure nickel oxide (NiO) is rather resistant to the attack by oxalic acid solutions, and ferrous ions do not accelerate dissolution. In fact, nickel oxide dissolves better by oxidative attack that takes advantage of the higher lability of Ni 3+ . It may be concluded that oxalic acid operates to dissolve iron, and the ensuing disruption of the solid framework accelerates the release of nickel. Our results point to use more reactive solvents in iron from mixed oxides and to the possibility of using one stage decontamination method. (author)

  3. Phytoremediation: an overview of metallic ion decontamination from soil

    Energy Technology Data Exchange (ETDEWEB)

    Singh, O.V.; Labana, S.; Pandey, G.; Budhiraja, R.; Jain, R.K. [Inst. of Microbial Technology, Chandigarh (India)

    2003-07-01

    In recent years, phytoremediation has emerged as a promising ecoremediation technology, particularly for soil and water cleanup of large volumes of contaminated sites. The exploitation of plants to remediate soils contaminated with trace elements could provide a cheap and sustainable technology for bioremediation. Many modern tools and analytical devices have provided insight into the selection and optimization of the remediation process by plant species. This review describes certain factors for the phytoremediation of metal ion decontamination and various aspects of plant metabolism during metallic decontamination. Metal-hyperaccumulating plants, desirable for heavily polluted environments, can be developed by the introduction of novel traits into high biomass plants in a transgenic approach, which is a promising strategy for the development of effective phytoremediation technology. The genetic manipulation of a phytoremediator plant needs a number of optimization processes, including mobilization of trace elements/metal ions, their uptake into the root, stem and other viable parts of the plant and their detoxification and allocation within the plant. This upcoming science is expanding as technology continues to offer new, low-cost remediation options. (orig.)

  4. Large-bore pipe decontamination

    International Nuclear Information System (INIS)

    Ebadian, M.A.

    1998-01-01

    The decontamination and decommissioning (D and D) of 1200 buildings within the US Department of Energy-Office of Environmental Management (DOE-EM) Complex will require the disposition of miles of pipe. The disposition of large-bore pipe, in particular, presents difficulties in the area of decontamination and characterization. The pipe is potentially contaminated internally as well as externally. This situation requires a system capable of decontaminating and characterizing both the inside and outside of the pipe. Current decontamination and characterization systems are not designed for application to this geometry, making the direct disposal of piping systems necessary in many cases. The pipe often creates voids in the disposal cell, which requires the pipe to be cut in half or filled with a grout material. These methods are labor intensive and costly to perform on large volumes of pipe. Direct disposal does not take advantage of recycling, which could provide monetary dividends. To facilitate the decontamination and characterization of large-bore piping and thereby reduce the volume of piping required for disposal, a detailed analysis will be conducted to document the pipe remediation problem set; determine potential technologies to solve this remediation problem set; design and laboratory test potential decontamination and characterization technologies; fabricate a prototype system; provide a cost-benefit analysis of the proposed system; and transfer the technology to industry. This report summarizes the activities performed during fiscal year 1997 and describes the planned activities for fiscal year 1998. Accomplishments for FY97 include the development of the applicable and relevant and appropriate regulations, the screening of decontamination and characterization technologies, and the selection and initial design of the decontamination system

  5. Decontamination of radioactively contaminated surfaces

    International Nuclear Information System (INIS)

    1986-10-01

    By this standard objective conditions to evaluate and test the ease of decontamination of surfaces under laboratory conditions are to be laid down. Ease of decontamination in this context denotes the summed-up effect of two material properties: a) the capacity of the material for retaining radioactive substances at its surface; b) the ease with which these substances are given off again in the course of cleaning processes. (orig./HP) [de

  6. Presolidification treatment of decontamination wastes

    International Nuclear Information System (INIS)

    Habayeb, M.A.

    1982-02-01

    Unsatisfactory leaching performance of several solidified decontamination solutions indicated a need for presolidification treatments to reduce the water sensitivity of the active chemicals. Chemical treatments examined in this work include pH adjustment, precipitation and oxidation-reduction reactions. The reactions involved in these treatments are discussed. The most suitable presolidification treatment for each decontamination solution has been identified. Further research is needed to test the effectivenss of these treatments

  7. Decontamination impacts on solidification and waste disposal

    International Nuclear Information System (INIS)

    Kempf, C.R.; Soo, P.

    1988-01-01

    Research to determine chemical and physical conditions which could lead to thermal excursions, gas generation, and/or general degradation of decontamination-reagent-loaded resins has shown that IRN-78, IONAC A-365, and IRN-77 organic ion exchange resin moisture contents vary significantly depending on the counter ion ''loading.'' The extent/vigor of the reaction is very highly dependent on the degree of dewatering of the resins and on the method of solution addition. The heat generation may be due, in part, to the heat of neutralization. In studies of the long-term compatibility effects of decontamination waste resins in contact with waste package container materials in the presence of decontamination reagents, radiolysis products and gamma irradiation, it has been found that the corrosion of carbon steel and austenitic stainless steel in mixed bed resins is enhanced by gamma irradiation. However, cracking in high density polyethylene is essentially eliminated because of the rapid removal of oxygen from the environment by gamma-induced oxidation of the large resin mass. 13 refs., 10 figs., 3 tabs

  8. Method of continuously regenerating decontaminating electrolytic solution

    International Nuclear Information System (INIS)

    Sasaki, Takashi; Kobayashi, Toshio; Wada, Koichi.

    1985-01-01

    Purpose: To continuously recover radioactive metal ions from the electrolytic solution used for the electrolytic decontamination of radioactive equipment and increased with the radioactive dose, as well as regenerate the electrolytic solution to a high concentration acid. Method: A liquid in an auxiliary tank is recycled to a cathode chamber containing water of an electro depositing regeneration tank to render pH = 2 by way of a pH controller and a pH electrode. The electrolytic solution in an electrolytic decontaminating tank is introduced by way of an injection pump to an auxiliary tank and, interlocking therewith, a regenerating solution is introduced from a regenerating solution extracting pump by way of a extraction pipeway to an electrolytic decontaminating tank. Meanwhile, electric current is supplied to the electrode to deposit radioactive metal ions dissolved in the cathode chamber on the capturing electrode. While on the other hand, anions are transferred by way of a partition wall to an anode chamber to regenerate the electrolytic solution to high concentration acid solution. While on the other hand, water is supplied by way of an electromagnetic valve interlocking with the level meter to maintain the level meter constant. This can decrease the generation of the liquid wastes and also reduce the amount of the radioactive secondary wastes. (Horiuchi, T.)

  9. A survey of decontamination processes applicable to DOE nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    Chen, L.; Chamberlain, D.B.; Conner, C.; Vandegrift, G.F.

    1997-05-01

    The objective of this survey was to select an appropriate technology for in situ decontamination of equipment interiors as part of the decommissioning of U.S. Department of Energy nuclear facilities. This selection depends on knowledge of existing chemical decontamination methods. This report provides an up-to-date review of chemical decontamination methods. According to available information, aqueous systems are probably the most universally used method for decontaminating and cleaning metal surfaces. We have subdivided the technologies, on the basis of the types of chemical solvents, into acid, alkaline permanganate, highly oxidizing, peroxide, and miscellaneous systems. Two miscellaneous chemical decontamination methods (electrochemical processes and foam and gel systems) are also described. A concise technical description of various processes is given, and the report also outlines technical considerations in the choice of technologies, including decontamination effectiveness, waste handing, fields of application, and the advantages and limitations in application. On the basis of this survey, six processes were identified for further evaluation. 144 refs., 2 tabs.

  10. Investigation of electro-kinetic methods for soil decontamination

    International Nuclear Information System (INIS)

    Shabanova, A.N.

    2000-01-01

    The choices of effective methods for ecological system decontamination, their perfection and introduction into practical use have been actual tasks for the Ural region. The objective of this work has been to study the potentials of electrical kinetics method of ISOTRON Corporation (US) for decontamination of the Urals soils. Results obtained have shown the method proposed to be usable for decontaminating some types of soils from strontium and plutonium; it is low effective for decontamination in the area of South-Urals radioactive plume. Thus, a low effectiveness can be expected in podsolic and leached laterite characterized by a high content of loamy sand and sandy soils, as well as for sobby-podsolic ones. The method can be promising for decontamination of soils and wastes from chemical contaminants, such as Zn, Ni, Cu, Pb, Hg, and others. Important advantages of this method compared to others have been its simplicity, small amount of wastes, and feasibility of decontamination in areas difficult to access. (authors)

  11. A survey of decontamination processes applicable to DOE nuclear facilities

    International Nuclear Information System (INIS)

    Chen, L.; Chamberlain, D.B.; Conner, C.; Vandegrift, G.F.

    1997-05-01

    The objective of this survey was to select an appropriate technology for in situ decontamination of equipment interiors as part of the decommissioning of U.S. Department of Energy nuclear facilities. This selection depends on knowledge of existing chemical decontamination methods. This report provides an up-to-date review of chemical decontamination methods. According to available information, aqueous systems are probably the most universally used method for decontaminating and cleaning metal surfaces. We have subdivided the technologies, on the basis of the types of chemical solvents, into acid, alkaline permanganate, highly oxidizing, peroxide, and miscellaneous systems. Two miscellaneous chemical decontamination methods (electrochemical processes and foam and gel systems) are also described. A concise technical description of various processes is given, and the report also outlines technical considerations in the choice of technologies, including decontamination effectiveness, waste handing, fields of application, and the advantages and limitations in application. On the basis of this survey, six processes were identified for further evaluation. 144 refs., 2 tabs

  12. Comparison of four different fuller's earth formulations in skin decontamination.

    Science.gov (United States)

    Roul, Annick; Le, Cong-Anh-Khanh; Gustin, Marie-Paule; Clavaud, Emmanuel; Verrier, Bernard; Pirot, Fabrice; Falson, Françoise

    2017-12-01

    Industrial accidents, wars and terrorist threats are potential sources of skin contamination by highly toxic chemical warfare agents and manufacturing compounds. We have compared the time-dependent adsorption capacity and decontamination efficiency of fuller's earth (FE) for four different formulations for the molecular tracer, 4-cyanophenol (4-CP), in vitro and ex vivo using water decontamination as standard. The adsorption capacity of FE was assessed in vitro for 4-CP aqueous solutions whereas decontamination efficiency was investigated ex vivo by tracking porcine skin 4-CP content using attenuated total reflectance Fourier transform infrared spectroscopy. Decontamination was performed on short time, exposed porcine skin to 4-CP by application of FE: (1) as free powder; (2) loaded on adhesive tape; (3) on powdered glove; or (4) in suspension. Removal rate of 4-CP from aqueous solutions correlates with the amount of FE and its contact time. Decontamination efficiency estimated by the percentage of 4-CP recovery from contaminated porcine skin, achieved 54% with water, ranged between ~60 and 70% with dry FE and reached ~90% with FE suspension. Successful decontamination of the FE suspension, enabling a dramatic reduction of skin contamination after a brief exposure scenario, appears to be rapid, reliable and should be formulated in a new device ready to use for self-application. Copyright © 2017 John Wiley & Sons, Ltd.

  13. Decontaminating lead bricks and shielding

    International Nuclear Information System (INIS)

    Lussiez, G.W.

    1993-01-01

    Lead used for shielding is often surface contaminated with radioisotopes and is therefore a RCRA D008 mixed waste. The technology-based standard for treatment is macroencapsulation. However, decontaminating and recycling the clean lead is a more attractive solution. Los Alamos National Laboratory decontaminates material and equipment contaminated with radioisotopes. Decontaminating lead poses special problems because of the RCRA hazard classification and the size of the inventory, now about 50 tons and likely to grow substantially because of planned decommissioning operations. This lead, in the form of bricks and other shield shapes, is surface contaminated with fission products. One of the best methods for decontaminating lead is removing the thin superficial layer of contamination with an abrasive medium trader pressure. For lead, a mixture of alumina with water and air at about 40 psig rapidly and effectively decontaminates the lead. The abrasive medium is sprayed onto the lead in a sealed-off area. The slurry of abrasive and particles of lead falls through a floor grating and is collected in a sump. A pump sends the slurry mixture back to the spray gun, creating a continuous process. The process generates small volumes of contaminated lead slurry that can be solidified and, because it passes the TCLP, is not a mixed waste. The decontaminated lead can be released for recycling

  14. Random Vibration Analysis of the XM2l Decontaminant Pumper Module of the Modular Decontamination System

    National Research Council Canada - National Science Library

    Colclough, Stephen

    1998-01-01

    The XM21 Decontaminant Pumper module of the Modular Decontamination System was analyzed using finite element analysis techniques to show why the first design iteration passed transportation vibration...

  15. Laser cleaner development for decontamination of the primary water cooling system at nuclear power plants

    International Nuclear Information System (INIS)

    Minehara, Eisuke

    2010-01-01

    We recently have performed the feasibility studies to develop laser cleaners utilizing several laser oscillator and amplifier systems like femto-second free-electron lasers, water-jet guided lasers, Q-switched YAG lasers, fiber lasers. Whenever we used to clean the RI-contaminated surface using the lasers, we should focus enough laser power in the surface to evaporate instantly without melting. Therefore, as the contaminated being deeply located into the surface could be removed using any one set of the lasers, we found that every trial of laser cleaning could remove very well the RI contamination being located deeply. Our cold decontamination test using a model sample being Cobalt plated successfully has been performed to show a very high decontamination factor. In order to develop an usable laser cleaner, we plan to develop the prototype laser cleaner next year. (author)

  16. Rapid and Highly Sensitive Detection of Variant Creutzfeldt-Jakob Disease Abnormal Prion Protein on Steel Surfaces by Protein Misfolding Cyclic Amplification: Application to Prion Decontamination Studies.

    Directory of Open Access Journals (Sweden)

    Maxime Belondrade

    Full Text Available The prevalence of variant Creutzfeldt-Jakob disease (vCJD in the population remains uncertain, although it has been estimated that 1 in 2000 people in the United Kingdom are positive for abnormal prion protein (PrPTSE by a recent survey of archived appendix tissues. The prominent lymphotropism of vCJD prions raises the possibility that some surgical procedures may be at risk of iatrogenic vCJD transmission in healthcare facilities. It is therefore vital that decontamination procedures applied to medical devices before their reprocessing are thoroughly validated. A current limitation is the lack of a rapid model permissive to human prions. Here, we developed a prion detection assay based on protein misfolding cyclic amplification (PMCA technology combined with stainless-steel wire surfaces as carriers of prions (Surf-PMCA. This assay allowed the specific detection of minute quantities (10-8 brain dilution of either human vCJD or ovine scrapie PrPTSE adsorbed onto a single steel wire, within a two week timeframe. Using Surf-PMCA we evaluated the performance of several reference and commercially available prion-specific decontamination procedures. Surprisingly, we found the efficiency of several marketed reagents to remove human vCJD PrPTSE was lower than expected. Overall, our results demonstrate that Surf-PMCA can be used as a rapid and ultrasensitive assay for the detection of human vCJD PrPTSE adsorbed onto a metallic surface, therefore facilitating the development and validation of decontamination procedures against human prions.

  17. Air Activated Self-Decontaminating Polydicyclopentadiene PolyHIPE Foams for Rapid Decontamination of Chemical Warfare Agents.

    Science.gov (United States)

    McGann, Christopher L; Daniels, Grant C; Giles, Spencer L; Balow, Robert B; Miranda-Zayas, Jorge L; Lundin, Jeffrey G; Wynne, James H

    2018-06-01

    The threat of chemical warfare agents (CWA) compels research into novel self-decontaminating materials (SDM) for the continued safety of first-responders, civilians, and active service personnel. The capacity to actively detoxify, as opposed to merely sequester, offending agents under typical environmental conditions defines the added value of SDMs in comparison to traditional adsorptive materials. Porous polymers, synthesized via the high internal phase emulsion (HIPE) templating, provide a facile fabrication method for materials with permeable open cellular structures that may serve in air filtration applications. PolyHIPEs comprising polydicyclopentadiene (polyDCPD) networks form stable hydroperoxide species following activation in air under ambient conditions. The hydroperoxide-containing polyDCPD materials react quickly with CWA simulants, Demeton-S and 2-chloroethyl ethyl sulfide, forming oxidation products as confirmed via gas chromatography mass spectrometry. The simplicity of the detoxification chemistry paired with the porous foam form factor presents an exciting opportunity for the development of self-decontaminating filter media. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Electrochemical decontamination of metallic surfaces by means of a movable electrode

    International Nuclear Information System (INIS)

    Mihai, F.; Nicu, M.; Cazan, L.; Turcanu, C.

    1998-01-01

    Electrochemical decontamination can be considered to be a decontamination assisted by an electrochemical field. The method is applied to the metallic surface decontamination for contaminants of any physico-chemical nature. The physico-chemical phenomenon that is the basis for the electrochemical methods is the anodic layer dissolution. By dissolution of the superficial layer any radioactive contaminant on the surface or entrapped within the surface oxide is eliminated. Electrochemical decontamination, also known as electropolishing, involves the use of the object to be cleaned as an anode in an electrochemical cell. The passage of current results in anodic dissolution of the surface material. Generally, there are many methods of application for electropolishing. The most common method is immersing the object to be decontaminated in a tank filled with a suitable electrolyte. The electrochemical method with movable electrode involves the use of 'in situ' mobile devices that are able to electropolish punctual surfaces in places difficult to access. The advantages are the simplicity of the setup, short times of application and reduced waste volumes. Phosphoric and sulphuric acid mixture is used as the electrolyte in electropolishing because of its stability, safety and applicability to a variety of alloy systems. The method was applied to decontaminate carbon steel, aluminium and copper. Used contaminants are mixtures of 60 Co and 134 Cs; 60 Co and 65 Zn; 60 Co, 65 Zn and 134 Cs. After preparation, the samples were kept in laboratory conditions about one month, to simulate real conditions and to let the chemical reactions between contaminant and sample material constitution to complete. To calculate decontamination factor characteristic for each studied decontamination method the following radiometric measurements are necessary: - activity measurement after radioisotope solution contamination representing initial activity Λ in ; - activity measurement after

  19. Vigorous decontamination tests of steel samples

    International Nuclear Information System (INIS)

    Agostinelli, A.; Bregani, F.; Pascali, R.; Ronchetti, C.

    1982-01-01

    Among operative deCommissioning problems, the chemical decontamination of metallic surfaces of LWR, mainly with the use of high vigorous reagents, is being studied in particular. ENEL research activities, partially financed by the European Community Commission, began at the end of 1980, and are being developed by CRTN, Centro di Ricerca Termica e Nucleare, in close connection with ENEL-DPT and CISE. The main aim is the identification, development, and assessment of vigorous decontamination techniques taking into account the amount and disposal cost of liquid radwaste. The test materials come from the primary loop of the BWR-Garigliano plant. Activity levels, mainly due to 60 Co, range from about 0.01 μCi/cm 2 for predecontaminated material to some μCi/cm 2 for virgin material. Moreover, traces of 90 Sr-Y beta pure emitter and alpha emitters are monitored. Research is at first carried out by screening static tests for the optimization of etching static parameters (time, temperature, reagent concentrations). Reagent effectiveness will then be tested in a special experimental loop (DECO), in dynamic conditions simulating in-situ real procedures of decontamination. Hydrofluoric, nitric and hydrochloric acids and mixtures of them have been used for the first tests. Sometimes total oxide removal is possible, and when this takes place, the final contamination levels are in accordance with limits indicated for unrestricted release materials in some countries. 18 references, 13 figures, 5 tables

  20. New technologies for PCB [polychlorinated biphenyl] decontamination

    International Nuclear Information System (INIS)

    Webber, I.

    1993-01-01

    Polychlorinated biphenyls (PCB) were mixed with chlorobenzenes to reduce viscosity and provide for both electrical insulation and convective heat transfers. These mixtures were known as askarels, and ca 99.8% of PCBs used in electrical applications are contained in askarel-filled transformers and capacitors. It is estimated that there are ca 180 million gal of PCB-contaminated oil distributed through over 3 million transformers in the USA. Technology used for decontaminating these transformers depends on the concentration of the PCB contamination. At low PCB concentrations of up to ca 2,000 ppM, chemical methods can be used; at higher concentrations, alternative disposal options become more attractive. For chemical treatment, a small mobile unit using quick-reacting reagents has been developed for on-site decontamination. For highly contaminated transformers, retrofilling is very attractive since the owner's liability is minimized at minimum cost. Conventional flush/drain procedures have such drawbacks as the inability to remove oil trapped in windings and the leaching of trapped PCBs back into the uncontaminated retrofill oil over time. A new process has been developed to solve the leaching problem and to decontaminate the drained askarel at room temperature using a catalyst. An alternative disposal strategy involves dismantling the transformer carcass, incinerating non-recyclable materials, and cleaning the metals and wire with solvent. 8 figs

  1. Liquid abrasive grit blasting literature search and decontamination scoping tests report

    International Nuclear Information System (INIS)

    Ferguson, R.L.

    1993-10-01

    Past decontamination and solvent recovery activities at the Idaho Chemical Processing Plant (ICPP) have resulted in the accumulation of 1.5 million gallons of radioactively contaminated sodium-bearing liquid waste. Future decontamination activities at the ICPP could result in the production of 5 million gallons or more of sodium-bearing waste using the current decontamination techniques of chemical/water flushes and steam jet cleaning. With the curtailment of reprocessing at the ICPP, the focus of decontamination is shifting from maintenance for continued operation of the facilities to decommissioning. As decommissioning plans are developed, new decontamination methods must be used which result in higher decontamination factors and generate lower amounts of sodium-bearing secondary waste. The primary initiative of the WINCO Decontamination Development Program is the development of methods to eliminate/minimize the use of sodium-bearing decontamination chemicals. One method that was chosen for cold scoping studies during FY-93 was abrasive grit blasting. Abrasive grit blasting has been used in many industries and a vast amount of research and development has already been conducted. However, new grits, process improvements and ICPP applicability was investigated. This evaluation report is a summary of the research efforts and scoping tests using the liquid abrasive grit blasting decontamination technique. The purpose of these scoping tests was to determine the effectiveness of three different abrasive grits: plastic beads, glass beads and alumina oxide

  2. Safety aspects in decontamination operations: Lessons learned during the decommissioning of a small PWR reactor

    International Nuclear Information System (INIS)

    Klein, M.; Ponnet, M.; Emond, O.

    2002-01-01

    Decontamination operations are generally executed during the decommissioning of nuclear installations for different objectives: decontamination of loops or large pieces to reduce the dose rate inside a contaminated plant or decontamination to minimize the amount of radioactive waste. These decontamination operations raise safety issues such as radiological exposure, classical safety, environmental releases, production and management of secondary waste, management of primary resources, etc. This paper presents the return of experience from decontamination operations performed during the dismantling of the BR3 PWR reactor. The safety issues are discussed for 3 types of decontamination operations: full system decontamination of the primary loop with a chemical process to reduce the dose rate by a factor of 10; thorough decontamination with an aggressive chemical process of dismantled pieces to reach the unconditional clearance values; and thorough decontamination processes with physical processes of metals and of concrete to reach the unconditional clearance values. For the protection of the workers, we must consider the ALARA aspects and the classical safety issues. During the progress of our dismantling operations, the dose rate issue was becoming less important but the classical safety issues were becoming preponderant due to the use of very aggressive techniques. For the protection of the environment, we must take all the precautions to avoid any leakages from the plant and we must use processes which minimize the use of toxic products and which minimize the production of secondary wastes. We therefore promote the use of regenerative processes. (author)

  3. AREVA NP decontamination concept for decommissioning. A comprehensive approach based on over 30 years experience

    International Nuclear Information System (INIS)

    Stiepani, Christoph

    2011-01-01

    Decontamination prior to Decommissioning and Dismantlement is imperative. Not only does it provide for minimization of personnel dose exposure but also maximization of the material volume available for free release. Since easier dismantling techniques in lower dose areas can be applied, the licensing process is facilitated and the scheduling and budgeting effort is more reliable. The most internationally accepted approach for Decontamination prior to Decommissioning projects is the Full System Decontamination (FSD). FSD is defined as the chemical decontamination of the primary cooling circuit, in conjunction with the main auxiliary systems. AREVA NP has long-term experience with Full System Decontamination for return to service of operating nuclear power plants as well as for decommissioning after shutdown. Since 1976, AREVA NP has performed over 500 decontamination applications and, from 1986, Decontaminations prior to Decommissioning projects which comprise virtually all NPP designs and plant conditions were performed: NPP designs: HPWR, PWR, and BWR by AREVA, Westinghouse, ABB and GE. Decontaminations performed shortly after final shutdown or several years later, and even after re-opening Safe Enclosure. High Alpha inventory and or low gamma/alpha ratio. Main Coolant chemistry (e.g., with and without Zn injection during operation). Fifteen Decontaminations prior to Decommissioning Projects have been performed successfully to date and the sixteenth FSD is now in the detailed engineering phase and is scheduled to commence late 2010. AREVA NP has developed a fully comprehensive approach for decontamination based on the CORD® (Chemical Oxidation Reduction Decontamination) Family, applied using the in-house designed decontamination equipment AMDA TM (Automatic Modular Decontamination Appliance). Based on the vast experience of AREVA NP in the field of decontamination, the Decontamination Concept for Decommissioning was developed. This concept ensures that the

  4. Electroosmotic decontamination of concrete

    International Nuclear Information System (INIS)

    Bostick, W.D.; Bush, S.A.; Marsh, G.C.; Henson, H.M.; Box, W.D.; Morgan, I.L.

    1993-03-01

    A method is described for the electroosmotic decontamination of concrete surfaces, in which an electrical field is used to induce migration of ionic contaminants from porous concrete into an electrolyte solution that may be disposed of as a low-level liquid radioactive waste (LLRW); alternately, the contaminants from the solution can be sorbed onto anion exchange media in order to prevent contaminant buildup in the solution and to minimize the amount of LLRW generated. We have confirmed the removal of uranium (and infer the removal of 99 Tc) from previously contaminated concrete surfaces. In a typical experimental configuration, a stainless steel mesh is placed in an electrolyte solution contained within a diked cell to serve as the negative electrode (cathode) and contaminant collection medium, respectively, and an existing metal penetration (e.g., piping, conduit, or rebar reinforcement within the concrete surface) serves as the positive electrode (anode) to complete the cell. Typically we have achieved 70 to >90% reductions in surface activity by applying 2 )

  5. New decontamination technologies for environmental applications

    International Nuclear Information System (INIS)

    Allen, R.P.; Arrowsmith, H.W.; McCoy, M.W.

    1981-01-01

    The technologies discussed represent a versatile collection of tools and approaches for environmental decontamination applications. The fixatives provide a means for gaining and maintaining control of large contaminated areas, for decontaminating large surface areas, and for protecting equipment and supplies used in decontamination operations. The other decontamination techniques together provide a method for removing loose surface contamination from almost all classes of materials and surfaces. These techniques should have wide application both as direct decontamination processes and for the cleaning of tools and equipment used in the decontamination operations

  6. Laser decontamination and cleaning of metal surfaces: modelling and experimental studies

    International Nuclear Information System (INIS)

    Leontyev, A.

    2011-01-01

    Metal surface cleaning is highly required in different fields of modern industry. Nuclear industry seeks for new methods for oxidized surface decontamination, and thermonuclear installations require the cleaning of plasma facing components from tritium-containing deposited layer. The laser ablation is proposed as an effective and safe method for metal surface cleaning and decontamination. The important factor influencing the laser heating and ablation is the in-depth distribution of laser radiation. The model of light propagation in a scattering layer on a metal substrate is developed and applied to analyse the features of light distribution. To simulate the contaminated surfaces, the stainless steel AISI 304L was oxidized by laser and in a furnace. Radioactive contamination of the oxide layer was simulated by introducing europium and/or sodium. The decontamination factor of more than 300 was demonstrated with found optimal cleaning regime. The decreasing of the corrosion resistance was found after laser cleaning. The ablation thresholds of ITER-like surfaces were measured. The cleaning productivity of 0.07 m 2 /hour.W was found. For mirror surfaces, the damage thresholds were determined to avoid damage during laser cleaning. The possibility to restore reflectivity after thin carbon layer deposition was demonstrated. The perspectives of further development of laser cleaning are discussed. (author) [fr

  7. Decontamination of transvaginal ultrasound probes: Review of national practice and need for national guidelines

    International Nuclear Information System (INIS)

    Gray, R.A.; Williams, P.L.; Dubbins, P.A.; Jenks, P.J.

    2012-01-01

    Aim: To determine the national practice of transvaginal ultrasound (TVUS) probe decontamination in English hospitals and to develop recommendations for guidance. Materials and methods: A literature review was undertaken to clarify best practice and evaluate methods of decontamination of TVUS probes. A questionnaire was developed to ascertain TVUS probe decontamination programmes in current use within English hospitals. This was sent to ultrasound leads of 100 English hospitals; 68 hospitals responded. Results: There is a wide variation in TVUS probe decontamination across English hospitals. Although the majority of respondents (87%, 59/68) reported having clear and practical written guidelines for TVUS decontamination, the frequency, methods, and types of decontamination solutions utilized were widely variable and none meet the standards required to achieve high-level disinfection. Conclusion: While the decontamination of other endoluminal medical devices (e.g., flexible endoscopes) is well defined and regulated, the decontamination of TVUS probes has no such guidance. There appears to be incomplete understanding of the level of risk posed by TVUS probes, and in some cases, this has resulted in highly questionable practices regarding TVUS hygiene. There is an urgent need to develop evidence-based national guidance for TVUS probe decontamination.

  8. Development of remote electrochemical decontamination for hot cell applications

    International Nuclear Information System (INIS)

    Turner, A.D.; Junkison, A.R.; Pottinger, J.S.; Lain, M.J.; Neville, M.D.; Dawson, R.K.; Fletcher, P.A.; Fenn-Tye, I.A.

    1993-01-01

    Electrochemical dissolution into nitric acid has been developed as a decontamination process for metallic items, both for immersion and in-situ use. Not only is the spent electrolyte compatible with existing waste treatment routes, potentially yielding an immobilized product volume of 0.6 dm 3 /m 2 area treated, but it also suppresses any hydrogen production. Both processes have been developed from laboratory to microprocessor-controlled pilot-scale units, which have been demonstrated successfully for the treatment of genuine waste, reducing activity levels to background. For stainless steel substrates, the immersion tank process uses low current densities (10-50 A/m 2 ) in 1-5M HN0 3 for the treatment of extended areas. Decontamination factors > 10 4 can be achieved in two hours. The in-situ technique uses electropolishing in 6M HN0 3 at 1-2 A/cm 2 in an engineered head. Decontamination factors > 10 3 can be achieved in only 20 seconds. This device has also shown potential for incorporation into an integrated monitoring/decontaminating system under robotic control. Both techniques may be used remotely as a way of reducing man-dose and improving productivity during decontamination. Additional cost savings can be made over currently used techniques through the decategorization of the bulk of the waste volume, and the volume reduction of waste for interim storage and geological disposal

  9. Experience of decontaminating of the ventilation system electric motors and main circulation and waterside pump drive electric motors in conditions of the Chernobyl' NPP

    International Nuclear Information System (INIS)

    Denisov, V.I.; Karataev, B.A.; Platonov, A.I.; Potekhin, V.B.; Ryumin, G.V.; Sorokin, N.M.; Fenogenov, V.A.; Cheremshin, P.I.

    1989-01-01

    The ventilation system electric motor decontamination is described. In decontaminating waterside pump rotors and stators with high level of contamination was developed a procedure, eliminating corrosion action and damage of electric isolation coatings

  10. Development of Nuclear Decontamination Technology Using Supercritical Fluid

    International Nuclear Information System (INIS)

    Jung, Wonyoung; Park, Kwangheon; Park, Jihye; Lee, Donghee

    2014-01-01

    Soil cleaning technologies that have been developed thus far increase treatment costs in contaminated soil recovery processes because they generate large amounts of secondary wastes. In this respect, this study is intended to develop soil decontamination methods using CO 2 , which is a nontoxic, environmentally friendly substance, in order to fundamentally suppress the generation of secondary wastes from the decontamination process and to create high added values. In this study, to develop decontamination methods for uranium-contaminated soil using supercritical CO 2 , a soil decontamination system using supercritical CO 2 was constructed. In addition, the basic principle of supercritical CO 2 decontamination using a TBP-HNO3 complex was explained. According to the results of the study, sea-sand samples having the same degree of contamination showed different results of decontamination according to the quantities of the TBP-HNO3 complex used as an extraction agent, which resulted in high extraction rates. Thus far, a most widely used method of extracting uranium has been the dissolving of uranium in acids. However, this method has the large adverse effect of generating strong acidic wastes that cannot be easily treated. On the other hand, supercritical CO 2 requires critical conditions that are no more difficult to meet than those of other supercritical fluids, since its density can be changed from a very low state close to that of an ideal gas to a high state close to that of liquids. The critical gas conditions are a pressure of 71 bar and a temperature of 31 .deg. C, both of which are inexpensive to achieve. Moreover, CO 2 is a solvent that is not harmful to the human body and few effects on environmental pollution. Therefore, nontoxic and environment friendly processes can be developed using supercritical CO 2 . Supercritical CO 2 's advantages over prevailing methods suggest its potential for developing innovative decontamination methods, as demonstrated

  11. High quality-factor optical resonators

    International Nuclear Information System (INIS)

    Henriet, Rémi; Salzenstein, Patrice; Coillet, Aurélien; Saleh, Khaldoun; Chembo, Yanne K; Ristic, Davor; Ferrari, Maurizio; Mortier, Michel; Rasoloniaina, Alphonse; Dumeige, Yannick; Féron, Patrice; Cibiel, Gilles; Llopis, Olivier

    2014-01-01

    Various resonators are investigated for microwave photonic applications. Micro-sphere, disk and fiber ring resonators were designed, realized and characterized. Obtained quality factors are as high as Q = 10 10 . (paper)

  12. CB decontamination for first responders

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, M.D.G.; Purdon, J.G.; Burczyk, A. [Defence Research and Development Canada Suffield, Ralston, AB (Canada)

    2006-07-01

    The Universal Containment System (UCS) is designed to contain, mitigate and decontaminate chemical, biological and radiological warfare agents. The UCS consists of a lightweight, tent-like enclosure filled with a water-based surface decontaminating foam (SDF). The Canadian government funded a project to advance the understanding of the behaviour of the UCS. This paper described the success of the project as well as the technological advances in the UCS formulation and equipment. Vapour desorption experiments were conducted in which SDF was applied onto 12 surfaces found in a typical office environment. Both mustard and nerve agent were studied on the test surfaces. Both scrubbing and non-scrubbing decontamination methods were tested. SDF effectively decontaminated the non-porous substances, particularly when the scrubbing procedure was used. Results were more complicated for the non-porous samples. A dye added to the agent was useful for determining the fate of the agent. Liquid phase studies were conducted in which the reaction between SDF and various agents were studied in the liquid phase in order to estimate the rate of reaction, the stoichiometry and the reaction products formed. Both SDF and the commercial decontamination agent CASCAD were found to effectively kill 100 per cent of anthrax spores. The significance of this project to first responders was considerable. Changes to the formulation and equipment of UCS will increase its usefulness and safety. Users will also have a better knowledge of the amount of decontamination needed for complete effectiveness in specific situations. Recommendations have been made for use of the product on a range of indoor surfaces. Field trials have shown the blast mitigation and agent decontamination ability of the foam under explosive situations. 15 refs., 4 tabs.

  13. New decontamination process using foams containing particles

    International Nuclear Information System (INIS)

    Guignot, S.; Faure, S.

    2008-01-01

    One key point in the dismantling of nuclear facilities is the thorough cleaning of radiation- exposed surfaces on which radioactive deposits have formed. This cleaning step is often achieved by successive liquid rinses with specific solutions containing alkaline, acidic, or even oxidizing species depending on whether the aim is to dissolve greasy deposits (like ter-butylphosphate) or to corrode surfaces on micrometric thicknesses. An alternative process to reduce the amount of chemicals and the volume of the resulting nuclear wastes consists in using the same but foamed solutions (1). Carrying less liquid, the resulting foams still display similar kinetics of dissolution rates and their efficiency is determined by their ability to hold sufficient wetnesses during the time required for the decontamination. Classical foam decontamination process illustrated by foam pulverization or circulation in the 90 turned five years ago into a specific static process using high-lifetime viscosified foam at a steady state. One way to slow down the liquid drainage is to raise liquid viscosity by adding organic viscosifiers like xanthan gum (2). In 2005, new studies started on an innovative process proposed by S. Faure and based on triphasic foams containing particles [3]. The aim is to generate new decontamination foams containing less quantities of organics materials (surfactants and viscosifiers). Silica particles are obviously known to stabilize or destabilize foams (4). In the frame of S. Guignot Ph.D., new fundamental studies are initiated in order to clarify the role of silica solid microparticles in these foams. Our final goal is to determine whether this kind of new foam can be stable for several hours for a decontamination process. The results we will report focus on wet foams used for nuclear decontamination and incorporating fumed silica. The study is conducted on a vertical foam column in a pseudo-free drainage configuration, and aims at investigating the influence of

  14. Decontaminating products for routine decontamination in nuclear power plants

    International Nuclear Information System (INIS)

    Henning, K.

    2001-01-01

    Routine decontamination work that has to be carried out in practical operation includes the cleaning of all kinds of surfaces such as floors, walls and apparatus, the decontamination of professional clothes and of the personnel. In order to ensure a trouble-free functioning of plants for the treatment of waste water and concentrate in nuclear power plants, radioactive liquid wastes appearing in the controlled area should be compatible with the treatment methods in practice. Radioactive concentrates and resides obtained from the treatment methods are mixed with matrix materials like cement or bitumen or treated by roller frame drying and thus are conditioned for intermediate or final storage. Several requirements should be made on decontaminating agents used in the controlled area. Some of these physical-chemical criteria will be described in detail. (R.P.)

  15. Actual situation on the field of decontamination in Slovak and Czech NPPs

    International Nuclear Information System (INIS)

    Prazska, M.; Rezbarik, J.; Solcanyi, M.; Trtilek, R.

    2002-01-01

    Many decontamination methods for various applications have proved to provide good results at Slovak and Czech nuclear power plants. A number of mechanical, chemical and electrochemical decontamination methods are available. The selection of a suitable method and decontamination technology is the result of a multicriterial optimization. The plants use the decontamination procedures described in the design documentation. New decontamination procedures aiming to minimize secondary radioactive wastes and corrosion attack on the basic material are being developed. No standardized qualification process, however, exists for such new procedures and large efforts are to be made to introduce them into practice. Methods for decommissioning purposes are based on static or dynamic application of decontamination solutions such as a mixture of formic acid + complexing agent + corrosion inhibitor or dilute HNO 3 . A process consisting in treatment in a solution containing formic acid + complexing agent + corrosion inhibitor (total concentration 3 - 4 mass %, temperature 30 - 35 deg C), whose effect is enhanced by the application of ultrasound (0.4 - 0.5 W per cm 2 decontaminated area) in a specially designed bath, is recommended for segmented metallic parts, which can be then released into the environment and recycled. Electrochemical decontamination in a bath is another efficient decontamination method to achieve unrestricted release of the material into the environment. Efficient decontamination of various highly contaminated materials can be attained by using an electrolyte solution based on citric acid (100 g.dm -3 ) + nitric acid (20 g.dm -3 ) + NH 4 NO 3 (50 g.dm -3 ) and applying a current density of 100 - 200 mA.cm -2 , electrolyte temperature 25 - 50 deg C, with one decontamination cycle period not exceeding 30 minutes. The best results are obtained by electrolysis followed by mechanical treatment using ultrasound. Electrochemical decontamination using a spraying

  16. RSDL decontamination of human skin contaminated with the nerve agent VX.

    Science.gov (United States)

    Thors, L; Lindberg, S; Johansson, S; Koch, B; Koch, M; Hägglund, L; Bucht, A

    2017-03-05

    Dermal exposure to low volatile organophosphorus compounds (OPC) may lead to penetration through the skin and uptake in the blood circulation. Skin decontamination of toxic OPCs, such as pesticides and chemical warfare nerve agents, might therefore be crucial for mitigating the systemic toxicity following dermal exposure. Reactive skin decontamination lotion (RSDL) has been shown to reduce toxic effects in animals dermally exposed to the nerve agent VX. In the present study, an in vitro flow-through diffusion cell was utilized to evaluate the efficacy of RSDL for decontamination of VX exposed to human epidermis. In particular, the impact of timing in the initiation of decontamination and agent dilution in water was studied. The impact of the lipophilic properties of VX in the RSDL decontamination was additionally addressed by comparing chemical degradation in RSDL and decontamination efficacy between the VX and the hydrophilic OPC triethyl phosphonoacetate (TEPA). The epidermal membrane was exposed to 20, 75 or 90% OPC diluted in deionized water and the decontamination was initiated 5, 10, 30, 60 or 120min post-exposure. Early decontamination of VX with RSDL, initiated 5-10min after skin exposure, was very effective. Delayed decontamination initiated 30-60min post-exposure was less effective but still the amount of penetrated agent was significantly reduced, while further delayed start of decontamination to 120min resulted in very low efficacy. Comparing RSDL decontamination of VX with that of TEPA showed that the decontamination efficacy at high agent concentrations was higher for VX. The degradation mechanism of VX and TEPA during decontamination was dissected by 31 P NMR spectroscopy of the OPCs following reactions with RSDL and its three nucleophile components. The degradation rate was clearly associated with the high pH of the specific solution investigated; i.e. increased pH resulted in a more rapid degradation. In addition, the solubility of the OPC in RSDL

  17. Decontaminating lead bricks and shielding

    International Nuclear Information System (INIS)

    Lussiez, G.

    1994-01-01

    Lead used for shielding is often surface contaminated with radioisotopes and is therefore a RCRA D008 mixed waste. The technology-based standard for treatment is macroencapsulation. However, decontaminating and recycling the clean lead is a more attractive solution. Los Alamos National Laboratory decontaminates material and equipment contaminated with radioisotopes. Decontaminating lead poses special problems because of the RCRA hazard classification and the size of the inventory, now about 50 tons and likely to grow substantially of planned decommissioning operations. Thus lead, in the form of bricks and other shield shapes, is surface contaminated with fission products. One of the best methods for contaminated lead is removing the superficial layer of contamination with an abrasive medium under pressure. For lead, a mixture of alumina with water and air at about 40 psig rapidly and effectively decontaminates the lead. The abrasive medium is sprayed onto the lead in a scaled-off area. The slurry of abrasive and particles of lead falls through a floor and is collected in a sump. A pump sends the slurry mixture back to the spray gun, creating a continuous process. The process generates small volumes of lead slurry that can be solidified and, because it passes the TCLP, is not a mixed waste. The decontaminated lead can be released for recycling

  18. Decontaminating lead bricks and shielding

    International Nuclear Information System (INIS)

    Lussiez, G.W.

    1993-01-01

    Lead used for shielding is often surface contaminated with radionuclides and is therefore a Resource Conservation and Recovery Act (RCRA) D008 mixed waste. The technology-based standard for treatment is macroencapsulation. However, decontaminating and recycling the clean lead is a more attractive solution. Los Alamos National Lab. decontaminates material and equipment contaminated with radioisotopes. Decontaminating lead poses special problems because of the RCRA hazard classification and the size of the inventory, now about 100 metric tons and likely to grow substantially because of planned decommissioning operations. This lead, in the form of bricks and other shield shapes, is surface contaminated with fission products. One of the best methods for decontaminating lead is removing the thin superficial layer of contamination with an abrasive medium under pressure. For lead, a mixture of alumina with water and air at about 280 kPa (40 psig) rapidly and effectively decontaminates the lead. The abrasive medium is sprayed onto the lead in a sealed-off area. The slurry of abrasive and particles of lead falls through a floor grating and is collected in a pump. A pump sends the slurry mixture back to the spray gun, creating a continuous process

  19. Liquid decontaminants for nuclear applications

    International Nuclear Information System (INIS)

    Henning, Klaus; Gojowczyk, Peter

    2011-01-01

    Decontaminants used in the nuclear field must meet a variety of requirements. On the one hand, the washing process must remove radioactive contamination and conventional dirt from the items washed. On the other hand, subsequent disposal of the washing water arisings must be feasible by the usual waste disposal pathway. One aspect of particular importance is unproblematic treatment of the radioactively contaminated waste water, as a rule low to medium active, whose final storage must be ensured. Decontaminants must not impair waste treatment processes, such as evaporation, filtration, and centrifuging, as well as further treatment of the concentrates and residues arising which are worked into matrix materials (cementation, bituminization), in drum drying or roller mill drying. For reasons of safety at work and environmental quality, also aspects of human toxicology and ecotoxicology must be taken into account. In this way, handling decontaminants will not jeopardize the health of personnel or cause potential long-term environmental damage. Liquid decontaminants, compared to powders, offer the advantage of automatic dosage. The liquid product is dosed accurately as a function of the washing program used. Liquid decontaminants can be handled safely in hot laundries without causing skin and eye contacts. (orig.)

  20. DECONTAMINATION TECHNOLOGIES FOR FACILITY REUSE

    International Nuclear Information System (INIS)

    Bossart, Steven J.; Blair, Danielle M.

    2003-01-01

    As nuclear research and production facilities across the U.S. Department of Energy (DOE) nuclear weapons complex are slated for deactivation and decommissioning (D and D), there is a need to decontaminate some facilities for reuse for another mission or continued use for the same mission. Improved technologies available in the commercial sector and tested by the DOE can help solve the DOE's decontamination problems. Decontamination technologies include mechanical methods, such as shaving, scabbling, and blasting; application of chemicals; biological methods; and electrochemical techniques. Materials to be decontaminated are primarily concrete or metal. Concrete materials include walls, floors, ceilings, bio-shields, and fuel pools. Metallic materials include structural steel, valves, pipes, gloveboxes, reactors, and other equipment. Porous materials such as concrete can be contaminated throughout their structure, although contamination in concrete normally resides in the top quarter-inch below the surface. Metals are normally only contaminated on the surface. Contamination includes a variety of alpha, beta, and gamma-emitting radionuclides and can sometimes include heavy metals and organic contamination regulated by the Resource Conservation and Recovery Act (RCRA). This paper describes several advanced mechanical, chemical, and other methods to decontaminate structures, equipment, and materials

  1. Full system decontamination feasibility studies

    International Nuclear Information System (INIS)

    Denault, R.P.; LeSurf, J.E.; Walschot, F.W.

    1988-01-01

    Many chemical decontaminations have been performed on subsystems in light water reactors (BWRs and PWRs) but none on the full system (including the fuel) of large, (>500 MWe) investor owned reactors. Full system decontaminations on pressure-tubed reactors have been shown to facilitate maintenance, inspection, repair and replacement of reactor components. Further advantages are increased reactor availability and plant life extension. A conceptual study has been performed for EPRI (for PWRs) and Commonwealth Edison Co (for BWRs) into the applicability and cost benefit of full system decontaminations (FSD). The joint study showed that FSDs in both PWRs and BWRs, with or without the fuel included in the decontamination, are feasible and cost beneficial provided a large amount of work is to be done following the decontamination. The large amounts of radioactive waste generated can be managed using current technologies. Considerable improvements in waste handling, and consequent cost savings, can be obtained if new techniques which are now reaching commercial application are used. (author)

  2. Radioactive Decontamination by Strippable Paint

    International Nuclear Information System (INIS)

    Chantaraparprachoom, N.; Mishima, K.

    1998-01-01

    The strippable paint, one of the adhesion method, is to decontaminate solid surface of materials or/and a large area. Two kinds of specimen planchet, SUS 304 stainless steel and polycarbonate plastic, contaminated with radioactive 137 Cs were studied under various conditions. It included surface bottom types, the flat and convex concentric circle type, normal condition at room temperature and overheat condition (∼80 degree celsius). This method used coating paints which contains some elements to have a reaction with radioactive materials selectively. ALARA-Decon clear, Rempack-X200 clear, JD-P5-Mrs.Coat and Pro-Blue-color guard were selected to use as the coating paints. The contaminated surface was coated by the strippable paint under the optimum time, followed by peeling the paint seal. The Rempack-X200 showed the best result, the highest decontamination efficiency which are about 99-100% for all conditions of specimens. The JD-P5 and ALARA-Decon showed good results, which are 98-99% decontamination efficiency for the normal condition set of specimens and about 94-97% for the overheat set of specimens. They can decontaminate polycarbonate specimens better than stainless steel specimens. The Pro-Blue-color guard showed the lowest decontamination efficiency of which 60% for polycarbonate specimens at normal condition and 40%, 30% for stainless steel specimens at normal and overheat conditions respectively. There was no effects of surface bottom types significantly

  3. Study of tritium decontamination of stainless steel, copper, aluminum metals by tritium dry desorption

    International Nuclear Information System (INIS)

    Xie Yun; Shi Zhengkun; Wu Tao

    2014-01-01

    In order to study the decontamination efficiency of stainless steel, copper, aluminum metals contaminated by tritium, the metals were decontaminated by exposing to UV, ozone, heating, and the combination of heating, UV and ozone. The result indicates that the elevation of temperature can obviously improve decontamination. While irradiated by 172 nm UV, the decontamination efficiency is low, but it is better while heated and irradiated by 172 nm UV. If the stainless steel is irradiated by 172 nm UV and heated at 500℃ for 4 h, the decontamination efficiency is 99.2%. There is better decontamination efficiency of copper while exposed to ozone. While exposed to ozone and heated at 500℃, the decontamination efficiencies of stainless steel, copper and aluminum are higher than 99.2%. The decontamination efficiency can more obviously improve when metal is heated at high temperature (500℃) than low temperature (300℃). The surface tritium of metal placed at 30 d after decontamination increases because of diffusion and penetration of the tritium. Resolution spectra of tritium show that there are four kinds of contamination adsorbed tritium of stainless steel. (authors)

  4. Chemical decontaminating method for stainless steel

    International Nuclear Information System (INIS)

    Onuma, Tsutomu; Akimoto, Hidetoshi.

    1990-01-01

    Radioactive metal wastes comprising passivated stainless steels are chemically decontaminated to such a radioactivity level as that of usual wastes. The present invention for chemically decontaminating stainless steels comprises a first step of immersing decontaminates into a sulfuric acid solution and a second step of immersing them into an aqueous solution prepared by adding oxidative metal salts to sulfuric acid, in which a portion of the surface of stainless steels as decontaminates are chemically ground to partially expose substrate materials and then the above-mentioned decontamination steps are applied. More than 90% of radioactive materials are removed in this method by the dissolution of the exposed substrate materials and peeling of cruds secured to the surface of the materials upon dissolution. This method is applicable to decontamination of articles having complicate shapes, can reduce the amount of secondary wastes after decontamination and also remarkably shorten the time required for decontamination. (T.M.)

  5. Comparison of dilute chemical decontaminations of RAPS-2 full primary heat transport system

    International Nuclear Information System (INIS)

    Bhat, H.R.

    2000-01-01

    First ever attempt to decontaminate a full primary system of an Indian PHWR was carried out at Rajasthan Atomic Power Station Unit -2 (RAPS-2) in August 1992. The decontamination factors obtained were moderate. The second attempt to decontaminate the same system was made in February 1996 with a different formulation. The decontamination factors obtained were lesser than the earlier attempt. The details of the two campaigns and their relative merits and demerits are discussed. Some more studies are required to be done before further implementation of the picolonic acid/ascorbic acid formulation. The 1992 attempt was with picolinic acid and ascorbic acid whereas the 1996 attempt was with EDTA + citric acid + ascorbic Acid (EAC ) formulation. A number of lessons were learnt from the first campaign and the improvements were applied during the subsequent decontamination campaigns at Madras Atomic Power station. The total iron removed and various radio nuclides removed are also detailed in the paper. Picolonic acid and ascorbic acid is a better formulation for decontamination of full PHT systems of Indian PHWRs. Use of EAC formulation generates a lot of crud which settles in narrow clearances. Picolonic Acid/Ascorbic Acid formulation does not generate any crud. Decontamination using a single cycle of the picolonic acid/ascorbic acid formulation is more effective than the decontamination using three cycles of EAC formulation. (author)

  6. Summary review of Mound Facility's experience in decontamination of concrete

    International Nuclear Information System (INIS)

    Combs, A.B.; Davis, W.P.; Garner, J.M.; Geichman, J.R.

    1980-01-01

    Most of the current concrete decontamination work at Mound Facility involves surfaces that are contaminated with plutonium-238. Approximately 60,000 sq. ft. of concrete floors will have to be decontaminated in Mound's current Decontamination and Decommissioning (D and D) Project. Although most of these surfaces are partially protected by a barrier (tile or paint), contaminated water and acid have penetrated these barriers. The technique for decontaminating these floors is desribed. The initial cleaning of the floor involes standard water and detergent. Acids are not used in cleaning as they tend to drive the contamination deeper into the concrete surface. Next, the floor tile is manually removed inside a temporary enclosure under negative and filtered ventilation. Finally, layers of contaminated concrete are mechanically removed inside the ventilated enclosure. The suspected depth and surface area of contamination determines the type of mechanical tool used. In summary, several generic methods of concrete decontamination can be utilized: chemical, such as water, detergent, acids, paint remover, strippable paints, etc.; rotary using sanders, grinders, scarifiers, etc.; impact such as pressure washers (hydrolasers), particle blasters, scabblers, needlers, spallers, paving and rock breakers, ram hoes, etc. The particular method used depends on several factors: surface and area involved; depth of contamination; cost and availability of equipment; usage safety and radiological control; and waste generated

  7. Chemical decontamination of stainless steel

    International Nuclear Information System (INIS)

    Onuma, Tsutomu; Akimoto, Hidetoshi

    1991-01-01

    The present invention concerns a method for chemical decontamination of radioactive metal waste materials contaminated with radioactive materials on the surface, generated in radioactive materials-handling facilities. The invention is comprised of a method of chemical decontamination of stainless steel, characterized by comprising a first process of immersing a stainless steel-based metal waste material contaminated by radioactive materials on the surface in a sulfuric acid solution and second process of immersing in an aqueous solution of sulfuric acid and oxidizing metal salt, in which a portion of the surface of the stainless steel to be decontaminated is polished mechanically to expose a portion of the base material before the above first and second processes. 1 figs., 2 tabs

  8. Remote Decontamination Facility and Repair Station for hot-cell manipulators

    International Nuclear Information System (INIS)

    Ryz, M.A.

    1977-01-01

    Increasingly high radiation levels on manipulators at the Whiteshell Nuclear Research Establishment, Pinawa, Manitoba, Canada, necessitated design and construction of a Remote Decontamination Facility and Repair Station. This facility reduces radiation levels on manipulators by an order of magnitude over previous hand decontamination techniques. The reduced radiation levels have allowed superior manipulator repair and maintenance, resulting in 50% fewer manipulator breakdowns

  9. Variation in the effect of carcass decontamination impacts the risk for consumers

    DEFF Research Database (Denmark)

    Ribeiro Duarte, Ana Sofia; Nauta, Maarten; Aabo, Søren

    2016-01-01

    •The variation of decontamination has an effect on consumer risk reduction.•The effect of variation on risk is lower when mean log reduction is high.•The effect of variation on risk also depends on initial carcass contamination.•The effect of decontamination should be expressed as consumer risk...

  10. Precipitation-adsorption process for the decontamination of nuclear waste supernates

    Science.gov (United States)

    Lee, L.M.; Kilpatrick, L.L.

    1982-05-19

    High-level nuclear waste supernate is decontaminated of cesium by precipitation of the cesium and potassium with sodium tetraphenyl boron. Simultaneously, strontium-90 is removed from the waste supernate sorption of insoluble sodium titanate. The waste solution is then filtered to separate the solution decontaminated of cesium and strontium.

  11. Decontamination before dismantling a fast breeder reactor primary cooling system

    International Nuclear Information System (INIS)

    Costes, J.R.; Antoine, P.; Gauchon, J.P.

    1997-01-01

    The large-scale decontamination of FBR sodium loops is a novel task, as only a limited number of laboratory-scale results are available to date. The principal objective of this work is to develop a suitable decontamination procedure for application to the primary loops of the RAPSODIE fast breeder reactor as part of decommissioning to Stage 2. After disconnecting the piping from the main vessel, the pipes were treated by circulating chemical solutions and the vessels by spraying. The dose rate in the areas to be dismantled was divided by ten. A decontamination factor of about 300 was obtained, and should allow austenitic steel parts to be melted in special furnaces for unrestricted release. (author)

  12. Decontamination of radioactive metal surfaces by plasma arc gouging

    International Nuclear Information System (INIS)

    Osamu, K.; Makoto, K.; Takao, K.

    1983-01-01

    Experiments have been carried out to develop a new decontamination method that applies plasma arc gouging for removal of a thin surface layer from radioactively contaminated metallic wastes. Plasma arc gouging has been carried out on stainless steel and carbon steel pipes. The torch nozzle and gouging angle have been optimized to increase the decontamination rate. A water film is formed on the pipe surface to reduce both dust concentration in the off-gas and prevent slag particles, which are splashed up by the plasma gas, from adhering to the gouged surface. Using chromium-electroplated carbon steel pipes as samples, a decontamination factor of >10 3 is obtained after gouging to a depth of about0.5 mm in combination with ultrasonic cleaning

  13. Decontamination by ultrafiltration of low radioactivity waste water from fuel element fabrication

    International Nuclear Information System (INIS)

    Muller, H.M.

    1984-01-01

    It could be demonstrated that waste waters which contain uranium in a filterable form, such as laundry and floor-cleaning waste, can be sufficiently decontaminated by means of ultra-filtration. In the case of process waste solutions, which contain uranium in a dissolved form, high decontamination factors could be achieved by means of flocculation or coprecipitation. The following methods were tested: - flocculation with Fe (OH) 3 , - coprecipitation with CaHPO 4 , - precipitation with K 4 (Fe(CN) 6 ). The phosphate precipitation, whereby the uranium is probably coprecipitated as Ca(UO 2 ) 2 (PO 4 ) 2 , was found to be the most reliable method. Difficulties were encountered when complex-forming anions, notably carbonate, oxalate and fluoride were present. These necessitate specific pretreatment steps. Whether ultrafiltration then still remains an economical option must be judged in each individual case. The application of the methods so far developed on combined waste streams remains an object for further research. In combination with a phosphate precipitation, ultrafiltration is a suitable method for the decontamination of low-activity, uranium-contaminated waste waters

  14. The separation of particulate within PFC decontamination wastewater generated by PFC decontamination

    International Nuclear Information System (INIS)

    Kim, Gye Nam; Lee, Sung Yeol; Won, Hui Jun; Jung, Chong Hun; Oh, Won Zin; Park, Jin Ho; Narayan, M.

    2005-01-01

    When PFC(Perfluoro carbonate) decontamination technology is applied to removal of radioactive contaminated particulate adhered at surface during the operation of nuclear research facilities, it is necessary to develop a filtration equipment to reuse of PFC solution due to high price, also to minimize the volume of second wastewater. Contaminated characteristics of hot particulate was investigated and a filtration process was presented to remove suspended radioactive particulate from PFC decontamination wastewater generated on PFC decontamination. The range of size of hot particulate adhered at the surface of research facilities measured by SEM was 0.1∼10μm. Hot particulate of more than 2μm in PFC contamination wastewater was removed by first filter and then hot particulate of more than 0.2μm was removed by second filter. Results of filter experiments showed that filtration efficiency of PVDF(Poly vinylidene fluoride), PP(Polypropylene), Ceramic filter was 95∼97%. A ceramic filter showed a higher filtration efficiency with a little low permeate volume. Also, a ceramic of inorganic compound could be broken easily on experiment and has a high price but was highly stable at radioactivity in comparison of PVDF and PP of a macromolecule which generate H 2 gas in alpha radioactivity environment

  15. Dwell time considerations for large area cold plasma decontamination

    Science.gov (United States)

    Konesky, Gregory

    2009-05-01

    Atmospheric discharge cold plasmas have been shown to be effective in the reduction of pathogenic bacteria and spores and in the decontamination of simulated chemical warfare agents, without the generation of toxic or harmful by-products. Cold plasmas may also be useful in assisting cleanup of radiological "dirty bombs." For practical applications in realistic scenarios, the plasma applicator must have both a large area of coverage, and a reasonably short dwell time. However, the literature contains a wide range of reported dwell times, from a few seconds to several minutes, needed to achieve a given level of reduction. This is largely due to different experimental conditions, and especially, different methods of generating the decontaminating plasma. We consider these different approaches and attempt to draw equivalencies among them, and use this to develop requirements for a practical, field-deployable plasma decontamination system. A plasma applicator with 12 square inches area and integral high voltage, high frequency generator is described.

  16. Physicochemical characteristics of PFC surfactants for dry decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Won Jin; Lee, Chi Woo [Korea University, Seoul (Korea)

    2001-04-01

    Even the trace amount of the used nuclear fuels of high radioactivity are hazardous to the earth and humans. Perfluorocarbons and perfluorocarbon surfactants are emerging to be efficient chemicals in the dry decontamination process of the used fuels of high radioactivity. The theme was undertaken to increase the knowledge on perfluorocarbon surfactants to develop the perfluorocarbon system in the dry decontamination process in Korea. Several cationic and anionic pfc surfactants were synthesized. Effects of pfc surfactants on electrochemical etching of silicon were investigated to form porous silicons. Forces were measured between silicon surfaces and AFM tip in the absence and presence of pfc surfactants. 7 refs., 10 figs. (Author)

  17. Solid Waste Decontamination by Thermal Desorption and Catalytic Oxidation Methods

    Czech Academy of Sciences Publication Activity Database

    Šolcová, Olga; Topka, Pavel; Soukup, Karel; Jirátová, Květa; Váňová, H.; Kaštánek, František

    2014-01-01

    Roč. 68, č. 9 (2014), s. 1279-1282 ISSN 0366-6352 R&D Projects: GA MPO FR-TI1/059 Institutional support: RVO:67985858 Keywords : thermal desorption * catalytic oxidation * soil decontamination Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.468, year: 2014

  18. Decontamination of Wastewater Contaminated by Polychlorinated Biphenyls (PCBs)

    Czech Academy of Sciences Publication Activity Database

    Kaštánek, František; Kaštánek, P.; Demnerová, K.; Maléterová, Ywetta

    2004-01-01

    Roč. 50, č. 2 (2004), s. 131-138 ISSN 0273-1223 Institutional research plan: CEZ:AV0Z4072921 Keywords : decontamination * hydrogen peroxide * underground water Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.586, year: 2004

  19. On the problem of radiation decontamination of the domestic sewage sludge

    International Nuclear Information System (INIS)

    Arbuzova, N.A.

    1978-01-01

    Soviet and foreign investigations on decontamination of drinking, natural, and waste waters with the use of gamma radiation are surveyed. A comparative analysis of data published on radiation decontamination showed that most experimental investigations were carried out on artificially prepared suspensions of microorganisms. The value of such investigations lies in the fact that they give the representation on the relative radiosensitivity of microorganisms in and aqueous medium and enable one to establish the effect of some physicochemical factors on the efficiency of radiation decontamination. Nevertheless, the results of the investigations carried out in this direction do not fully reflect actual conditions at existing decontamination stations and connot serve as a basis for estimating the technological and economic efficiency of the radiation decontamination method

  20. Evaluation of six decontamination processes on actinide and fission product contamination

    International Nuclear Information System (INIS)

    Conner, C.; Chamberlain, D.B.; Chen, L.

    1995-01-01

    In-situ decontamination technologies were evaluated for their ability to: (1) reduce equipment contamination levels to allow either free release of the equipment or land disposal, (2) minimize residues generated by decontamination, and (3) generate residues that are compatible with existing disposal technologies. Six decontamination processes were selected. tested and compared to 4M nitric acid, a traditional decontamination agent: fluoroboric acid (HBF 4 ), nitric plus hydrofluoric acid, alkaline persulfate followed by citric acid plus oxalic acid, silver(II) plus sodium persulfate plus nitric acid, oxalic acid plus hydrogen peroxide plus hydrofluoric acid, and electropolishing using nitric acid electrolyte. The effectiveness of these solutions was tested using prepared 304 stainless steel couponds contaminated with uranium, plutonium, americium, or fission products. The decontamination factor for each of the solutions and tests conditions were determined; the results of these experiments are presented

  1. Study to produce polymer gel for decontamination on the surface of steel, ceramic, plastic, glass

    International Nuclear Information System (INIS)

    Pham Quynh Luong; Nguyen Van Chinh; Nguyen Thu Trang; Nguyen An Thai; Nguyen Dinh Lam

    2015-01-01

    Strippable polymer coating is one of the methods for effective surface decontamination. A gel solution of a water soluble polymer, preferably polyvinyl alcohol (PVA) and chelating agent is applied to remove radioisotopes of Cs"1"3"7, Sr"8"5, I"1"3"1, P"3"2 and Tc"9"9"m on the surface of stainless steel, mild steel, ceramic, PVC plastic. After cleaning is completed, the gel solution is dried, formed a strong thin film, which is easily peeled off from a contaminated surface and can be disposed of as radioactive solid waste. Decontamination efficient of this gel polymer for radioisotopes have been studied on the surfaces and compared with Decongel 1101. The influence of decontamination agents, activity, film thickness to decontamination factor have been studied. The infrared spectrophotometer has been conducted to study mechanism of the decontamination for this radioisotope. (author)

  2. Report on practical use of new decontamination technology

    International Nuclear Information System (INIS)

    Nitta, Hideyuki; Ono, Masahiro

    2000-03-01

    For removing surface contamination of a solid waste with radioactivity, technology of laser cleaning and vacuum arc cleaning has the possibility to obtain the high decontamination rate. We made a research for practical uses of these methods as a new cleaning technology from published papers and patents. From these results, we discussed about an applicability of laser cleaning and vacuum arc cleaning to decontaminate a body of centrifugal separator. At first, we investigate the solid surface cleaning technology with a laser or a vacuum arc from published papers in the world and the patents in Japan. The results were listed in tables. Each information was abstracted into a technical data sheet and sorted into a related technology (system or equipment). We also investigate the decontamination technology by the same way and the results were abstracted into technical data sheets and sorted into related technologies, too. As an application of the above research, we considered the process and the system for decontaminating a body of centrifugal separators (cylinders). In the system, the cleaning head is set inside the cylinder and the inner surface contaminated by radioactivity is removed by the irradiation of a YAG laser, a CO2 laser or a vacuum arc. The cylinder is rotated by rotational rings and moved towards the direction of the central axis and the whole inner surface of the cylinder is cleaned with a constant cleaning rate. We also estimated the costs of each decontamination technology. (author)

  3. Electrochemical Decontamination of Painted and Heavily Corroded Metals

    International Nuclear Information System (INIS)

    Marczak, S.; Anderson, J.; Dziewinski, J.

    1998-01-01

    The radioactive metal wastes that are generated from nuclear fuel plants and radiochemical laboratories are mainly contaminated by the surface deposition of radioactive isotopes. There are presently several techniques used in removing surface contamination involving physical and chemical processes. However, there has been very little research done in the area of soiled, heavily oxidized, and painted metals. Researchers at Los Alamos National Laboratory have been developing electrochemical procedures for the decontamination of bare and painted metal objects. These methods have been found to be effective on highly corroded as well as relatively new metals. This study has been successful in decontaminating projectiles and shrapnel excavated during environmental restoration projects after 40+ years of exposure to the elements. Heavily corroded augers used in sampling activities throughout the area were also successfully decontaminated. This process has demonstrated its effectiveness and offers several advantages over the present metal decontamination practices of media blasting and chemical solvents. These advantages include the addition of no toxic or hazardous chemicals, low operating temperature and pressure, and easily scaleable equipment. It is in their future plans to use this process in the decontamination of gloveboxes destined for disposal as TRU waste

  4. Radiological decontamination, survey, and statistical release method for vehicles

    International Nuclear Information System (INIS)

    Goodwill, M.E.; Lively, J.W.; Morris, R.L.

    1996-06-01

    Earth-moving vehicles (e.g., dump trucks, belly dumps) commonly haul radiologically contaminated materials from a site being remediated to a disposal site. Traditionally, each vehicle must be surveyed before being released. The logistical difficulties of implementing the traditional approach on a large scale demand that an alternative be devised. A statistical method for assessing product quality from a continuous process was adapted to the vehicle decontamination process. This method produced a sampling scheme that automatically compensates and accommodates fluctuating batch sizes and changing conditions without the need to modify or rectify the sampling scheme in the field. Vehicles are randomly selected (sampled) upon completion of the decontamination process to be surveyed for residual radioactive surface contamination. The frequency of sampling is based on the expected number of vehicles passing through the decontamination process in a given period and the confidence level desired. This process has been successfully used for 1 year at the former uranium millsite in Monticello, Utah (a cleanup site regulated under the Comprehensive Environmental Response, Compensation, and Liability Act). The method forces improvement in the quality of the decontamination process and results in a lower likelihood that vehicles exceeding the surface contamination standards are offered for survey. Implementation of this statistical sampling method on Monticello projects has resulted in more efficient processing of vehicles through decontamination and radiological release, saved hundreds of hours of processing time, provided a high level of confidence that release limits are met, and improved the radiological cleanliness of vehicles leaving the controlled site

  5. Definition of a concrete bio-decontamination process in nuclear substructures; Biodegradation de matrices cimentaires en vue de leur decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Jestin, A

    2005-05-15

    The decontamination of sub-structural materials represents a stake of high-importance because of the high volume generated. It is agreed then to propose efficient and effective processes. The process of bio-decontamination of the hydraulic binders leans on the mechanisms of biodegradation of concretes, phenomenon characterized in the 40's by an indirect attack of the material by acids stem from the microbial metabolism: sulphuric acid (produced by Thiobacillus), nitric acid (produced by Nitrosomonas and Nitrobacter) and organic acids (produced by fungi). The principle of the bio-decontamination process is to apply those micro-organisms on the surface of the contaminated material, in order to damage its surface and to retrieve the radionuclides. One of the multiple approaches of the process is the use of a bio-gel that makes possible the micro-organisms application. (author)

  6. How Clean is Safe? Improving the Effectiveness of Decontamination of Structures and People Following Chemical and Biological Incidents

    Energy Technology Data Exchange (ETDEWEB)

    Vogt (Sorensen), B.M.

    2003-04-03

    This report describes a U.S. Department of Energy, (DOE) Chemical and Biological National Security Program project that sought to establish what is known about decontamination of structures, objects, and people following an exposure to chemical or biological materials. Specifically we sought to identify the procedures and protocols used to determine when and how people or buildings are considered ''clean'' following decontamination. To fulfill this objective, the study systematically examined reported decontamination experiences to determine what procedures and protocols are currently employed for decontamination, the timeframe involved to initiate and complete the decontamination process, how the contaminants were identified, the factors determining when people were (or were not) decontaminated, the problems encountered during the decontamination process, how response efforts of agencies were coordinated, and the perceived social psychological effects on people who were decontaminated or who participated in the decontamination process. Findings and recommendations from the study are intended to aid decision-making and to improve the basis for determining appropriate decontamination protocols for recovery planners and policy makers for responding to chemical and biological events.

  7. Evaluation of zeolite mixtures for decontamination of high-activity-level water in the Submerged Demineralizer System (SDS) flowsheet at the Three Mile Island Nuclear Power Station, Unit 2

    International Nuclear Information System (INIS)

    King, L.J.; Campbell, D.O.; Collins, E.D.; Knauer, J.B.; Wallace, R.M.

    1983-01-01

    Mixtures of Linde Ionsiv IE-96 and Ionsiv A-51 zeolites were evaluated for use in the Submerged Demineralizer System (SDS) that was installed at the Three Mile Island Nuclear Power Station, Unit 2 (TMI-2) for decontaminating approx. 3000 m 3 (approx. 700,000 gal) of high-activity-level water in the containment building sump. Small-scale, tracer-level column tests were made using various mixtures of the zeolites to evaluate the capability for simultaneous removal of cesium and strontium. A column loading test was made in a hot cell using a mixture of equal parts of the zeolites to evaluate the performance of the mixture in removing cesium and strontium from a sample of TMI-2 sump water. A computerized mathematical model of the mixed-bed SDS system was used to evaluate the test data in order to select a zeolite mixture and predict system performance

  8. Decontamination of Savannah River Plant H-Area hot-canyon crane

    International Nuclear Information System (INIS)

    Rankin, W.N.; Sims, J.R.

    1985-01-01

    Decontamination techniques applicable to the remotely operated bridge cranes in canyon buildings at the Savannah River Plant (SRP) were identified and were evaluated in laboratory-scale tests. High pressure Freon blasting was found to be the most attractive process available for this application. Strippable coatings were selected as an alternative technique in selected applications. The ability of high pressure Freon blasting plus two strippable coatings (Quadcoat 100 and Alara 1146) to remove the type of contamination expected on SRP cranes was demonstrated in laboratory-scale tests. Quadrex HPS was given a contract to decontaminate the H-Area hot canyon crane. Decontamination operations were successfully carried out within the specified time-frame window. The radiation level goals specified by SRP were met and decontamination was accomplished with 85% less personnel exposure than estimated by SRP before the job started. This reduction is attributed to the increased efficiency of the new decontamination techniques used. 6 refs., 1 tab

  9. ORNL decontamination and decommissioning program

    International Nuclear Information System (INIS)

    Bell, J.P.

    1980-01-01

    A program has been initiated at ORNL to decontaminate and decommission surplus or abandoned nuclear facilities. Program planning and technical studies have been performed by UCC-ND Engineering. A feasibility study for decommissioning the Metal Recovery Facility, a fuel reprocessing pilot plant, has been completed

  10. Decontamination in a Russian settlement

    DEFF Research Database (Denmark)

    Fogh, C.L.; Andersson, Kasper Grann; Barkovsky, A.N.

    1999-01-01

    Decontamination was carried out in an area with three houses in Novo Bobovichi, Bryansk region, Russia, in the autumn of 1995. It was demonstrated that significant reductions in the dose rate both indoor (DRF = 0.34) and outdoor (DRF = 0.20) can be achieved when a controlled cleaning is undertake...

  11. Decontaminating reagents for radioactive systems

    International Nuclear Information System (INIS)

    Seddon, W.A.

    1982-01-01

    A decontaminating reagent composition has been developed comprising EDTA, citric acid, oxalic acid, and formic acid. Formic acid inhibits the decomposition of both EDTA and citric acid, and yields oxalic acid as a result of its own radiolysis. The invention includes the improvement of initially incorporating formic acid in the mixture and maintaining the presence of formic acid by at least one further addition

  12. Radioactive decontamination through UV laser

    International Nuclear Information System (INIS)

    Delaporte, Ph.; Gastaud, M.; Sentis, M.; Uteza, O.; Marine, W.; Thouvenot, P.; Alcaraz, J.L.; Le Samedy, J.M.; Blin, D.

    2003-01-01

    A device allowing the radioactive decontamination of metal surfaces through the use of a pulsed UV laser has been designed and tested. This device is composed of a 1 kW excimer laser linked to a bundle of optic fibers and of a system to recover particles and can operate in active zones. Metal surfaces have the peculiarities to trap radio-elements in a superficial layer of oxide that can be eaten away by laser radiation. Different contaminated metals (stainless steels, INCONEL and aluminium) issued from the nuclear industry have been used for the testing. The most important contaminants were 60 Co, 137 Cs, 154-155 Eu and 125 Sb. The ratio of decontamination was generally of 10 and the volume of secondary wastes generating during the process was very low compared with other decontamination techniques. A decontamination speed of 1 m 2 /h has been reached for aluminium. The state of the surface is an important parameter because radio-elements trapped in micro-cracks are very difficult to remove. (A.C.)

  13. Decontamination laboratory design for iron pipes contaminated with uranium and thorium series

    International Nuclear Information System (INIS)

    Sahyun, Adelia; Sordi, Gian M.; Ghobril, Carlos N.; Puga Sanches, Matias; Rodrigues, Demerval L.

    2008-01-01

    The Brazilian soil is very rich in the ore processing, after some time, the pipes are contaminated with trace levels of uranium and thorium. When the pipes are exchanged, to recovery the funds, the best is to sell them as scrap, however, because they are contaminated and present a considerable amount of dose can not be marketed until they are decontaminated. The question is that the tube is incrusted with the contaminated material, and is difficult to remove it. For the removal this material, that comes to be 2 inches thick, for the larger pipes diameter, requires special equipment as a motor-pump units with ultra high pressure water jetting, of the order of 40000 psi. The purpose of this paper is to suggest a design of one laboratory able to perform the decontamination avoiding large scale production of radioactive wastes. The solids and liquids wastes produced during the process of decontamination will be collected in different containers and classified according to their contamination level. The laboratory was designed to facilitate its decontamination with a minimum dose for their operators. The most difficult question to be solved during the project, was to perform the laboratory decontamination during the pipe decontamination in continuous operation since we can't stop the process for the reason of it expensive cost. The paper will show how will be made all the steps of the tubes decontamination and the laboratory decontamination. It will be shown how we collect the liquids and solids wastes, separate, for their classification. After the pipe, decontamination we show as will be measure the dose to release or to return for the laboratory to development a further decontamination. At last, it will show the temporary storage place for the decontaminated pipes that will be later collected as scrap. (author)

  14. Decontamination and decommission of a radiochemical laboratory building complex

    International Nuclear Information System (INIS)

    Zoubek, Norbert

    2008-01-01

    Full text: Handling of unsealed radioactive substances for research and development purposes in chemical or pharmaceutical industries or research centres as well as production of radioactive substances (e.g. for applications in nuclear medicine or industry) requires operation of special radiochemical laboratories. In general, operation of radiochemical laboratories is strongly regulated by the government and national authorities. The operator needs a permit related to radiological protection. In general, technical requirements for such facilities are very high. To ensure high safety standards with respect to the employees and the environment, several radiological protection measures have to be taken. These measures (for example special shielding or ventilation and waste water systems) depend on various factors, e.g. activity in use, kind of nuclides, chemical properties and volatility of substances. In order to close-down such radiochemical laboratories some radiological protection measures have to be maintained to ensure protection of both humans and the environment induced by possible residual contaminations within the facility including technical inventory. However, a later reuse of the facility as a non-radioactive facility requires removal of all radioactive contamination with respect to national regulation. Resulting radioactive wastes have to be disposed of under control of competent authorities. Based on the experience of a decontamination and decommission project for a former radiochemical laboratory complex, the main steps necessary to release such a facility are discussed. Analytical aspects of initial conditions, necessary organisational structures within the project, resources needed estimation and exploration of the radiological situation in the laboratory, elaboration of a measuring strategy and decontamination methods as well as different waste disposal routes in relation to different waste types are reported. (author)

  15. Decontamination in the Republic of Belarus

    International Nuclear Information System (INIS)

    Antsipov, G.V.; Matveenko, S.A.; Mirkhaidarov, A.Kh.

    2002-01-01

    To continue the decontamination work in the Republic of Belarus, which was carried out by the military troops, the state specialized enterprises were formed in Gomel and Mogilev in 1991. The organization and regulations were developed inside the country: instructions, rules, radiological and hygienic criteria and norms. The enterprises concentrated on decontamination of the most socially significant facilities: kindergartens, schools, medical institutions and industrial enterprises. During 9 years Gomel State Specialized Enterprise 'Polessje' decontaminated 130 kindergartens, schools and hospitals. The total decontaminated area was 450 000 m 2 . The ventilation systems and equipment at 27 industrial enterprises in Gomel were decontaminated. The practical decontamination methods for areas, buildings, roofs, industrial equipment, ventilation systems were developed and tested. The special rules for handling wastes contaminated with Cs were elaborated. The paper analyzes and sums up the acquired experience which is important for implementation of rehabilitation programs and improvement of decontamination methods. (author)

  16. Heavy metal decontamination of sludges and soils. Pt. 2

    International Nuclear Information System (INIS)

    Niemann, J.

    1993-06-01

    This research project deals with decontamination technology for contaminated soil and sediments. A pilot plant for the decontamination of soil contaminated with heavy metals has been erected and is operated. The process is arranged in two steps: - heavy metal contaminated solid is decontaminted with acidic extraction. - the heavy metals are separated in a recyclable formation from the process solution you gain in the first process step. Heavy metal contaminated soil, heavy metal contaminated sediments (habour sediments) as well as residue from a soil regeneration plant have been successfully decontaminated in the pilot plan. An adaption of the process is necessary for various materials. High rates of mobilisation of heavy metals (e.g. lead, cadmium, chromium, copper, nickel, zinc) were obtained, especially with soil which contains less organic matter. (orig.). 54 figs., 30 tabs., 45 refs [de

  17. Study of the characterization and formulation of the decontamination gels

    Energy Technology Data Exchange (ETDEWEB)

    Park, Youn Bong; Bang, In Bae; Bae, Bong Moon; Oh, Gyu Hwan [Chungnam National University, Daejeon (Korea, Republic of)

    2011-04-15

    To develop a chemical gel decontamination technology for a removal of non-fixed contaminants during the maintenance and decommissioning works of high radiation hot cells which have been used for a recycling or treatment of spent fuels we have prepare gels with CAB-O-SIL M-5 or Aerosil 380 as viscosifier and some non-ionic surfactants such as diethylene glycol hexyl ether, triethylene glycol dodecyl ether, polyethylene glycol 600, and triethylene glycol butyl ether. Surfactants are playing important roles in manipulating the properties of decontamination the gels. We have found the CAB-O-SIL with triethylene glycol butyl ether and Aerosil with triethylene glycol dodecyl ether systems promising for the decontamination work

  18. Optimization of the decontamination in EDF PWR power plants

    International Nuclear Information System (INIS)

    Gosset, P.; Dupin, M.; Buisine, D.; Buet, J.F.; Brunel, V.

    2002-01-01

    The optimisation of decontamination in EDF PWR power plants is the result of a permanent collaborative work between the plant operators, the subcontractors, central services of nuclear power division of EDF. This collaborative work enables the saving of all the feedback experience. The main operations carried out on nuclear sites like mechanical decontamination of valves, use of the ''EMMAC'' process on big components (replacement of steam generator, hydraulic parts of the reactor coolant pumps), use of foam on pools walls and divers in highly contaminated pools have been discussed. This paper shows that the choice of decontamination processes is very dependant on the components, on the dose rate reduction to be aimed and on the possibility to treat the waste on site. (authors)

  19. Systems analysis of decontamination options for civilian vehicles.

    Energy Technology Data Exchange (ETDEWEB)

    Foltz, Greg W.; Hoette, Trisha Marie

    2010-11-01

    The objective of this project, which was supported by the Department of Homeland Security (DHS) Science and Technology Directorate (S&T) Chemical and Biological Division (CBD), was to investigate options for the decontamination of the exteriors and interiors of vehicles in the civilian setting in order to restore those vehicles to normal use following the release of a highly toxic chemical. The decontamination of vehicles is especially challenging because they often contain sensitive electronic equipment, multiple materials some of which strongly adsorb chemical agents, and in the case of aircraft, have very rigid material compatibility requirements (i.e., they cannot be exposed to reagents that may cause even minor corrosion). A systems analysis approach was taken examine existing and future civilian vehicle decontamination capabilities.

  20. Study of the characterization and formulation of the decontamination gels

    International Nuclear Information System (INIS)

    Park, Youn Bong; Bang, In Bae; Bae, Bong Moon; Oh, Gyu Hwan

    2011-04-01

    To develop a chemical gel decontamination technology for a removal of non-fixed contaminants during the maintenance and decommissioning works of high radiation hot cells which have been used for a recycling or treatment of spent fuels we have prepare gels with CAB-O-SIL M-5 or Aerosil 380 as viscosifier and some non-ionic surfactants such as diethylene glycol hexyl ether, triethylene glycol dodecyl ether, polyethylene glycol 600, and triethylene glycol butyl ether. Surfactants are playing important roles in manipulating the properties of decontamination the gels. We have found the CAB-O-SIL with triethylene glycol butyl ether and Aerosil with triethylene glycol dodecyl ether systems promising for the decontamination work

  1. Concrete decontamination by Electro-Hydraulic Scabbling (EHS)

    International Nuclear Information System (INIS)

    1994-11-01

    EHS is being developed for decontaminating concrete structures from radionuclides, organic substances, and hazardous metals. EHS involves the generation of powerful shock waves and intense cavitation by a strong pulsed electric discharge in a water layer at the concrete surface; high impulse pressure results in stresses which crack and peel off a concrete layer of controllable thickness. Scabbling produces contaminated debris of relatively small volume which can be easily removed, leaving clean bulk concrete. Objective of Phase I was to prove the technical feasibility of EH for controlled scabbling and decontamination of concrete. Phase I is complete

  2. Concrete decontamination by Electro-Hydraulic Scabbling (EHS)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-11-01

    EHS is being developed for decontaminating concrete structures from radionuclides, organic substances, and hazardous metals. EHS involves the generation of powerful shock waves and intense cavitation by a strong pulsed electric discharge in a water layer at the concrete surface; high impulse pressure results in stresses which crack and peel off a concrete layer of controllable thickness. Scabbling produces contaminated debris of relatively small volume which can be easily removed, leaving clean bulk concrete. Objective of Phase I was to prove the technical feasibility of EH for controlled scabbling and decontamination of concrete. Phase I is complete.

  3. Development of a strategy for decontamination of an urban area

    International Nuclear Information System (INIS)

    Roed, J.; Andersson, K.G.

    2000-01-01

    The Chernobyl accident in 1986 lead to high level contamination in urban areas in different parts of Europe and showed the importance of preparedness in the optimisation of any mitigatory interference. To meet this demand, a method for development of a decontamination strategy for urban areas has been developed based on measurements of radionuclide distribution in the urban environment after the Chernobyl accident, calculations of dose and experimentally obtained data on effectiveness and cost of practicable clean-up procedures. The approach highlights where decontamination would be of greatest benefit in terms of dose reduction and cost. (author)

  4. Decontamination of radioactive contaminated protective wear using dry cleaning solvent

    International Nuclear Information System (INIS)

    Muthiah, Pushpa; Chitra, S.; Paul, Biplob

    2013-01-01

    Liquid waste generated by conventional decontamination of radioactive contaminated cotton protective wear using detergent affects the chemical treatment of the plant. To reduce the generation of aqueous detergent waste, dry cleaning of cotton protective wear, highly soiled with oil and grease towards decontamination was tried with organic solvents. Mineral turpentine oil (MTO) among various other organic solvents was identified as a suitable organic solvent. As MTO leaves characteristic odour on the cloth, various commercial fragrances for the removal of the odour were tried. Application of the optimised dry cleaning solvent and commercial fragrance was adopted in plant scale operation. (author)

  5. Decontamination Options for Drinking Water Contaminated with Bacillus anthracis Spores

    Energy Technology Data Exchange (ETDEWEB)

    Raber, E; Burklund, A

    2010-02-16

    Five parameters were evaluated with surrogates of Bacillus anthracis spores to determine effective decontamination options for use in a contaminated drinking water supply. The parameters were: (1) type of Bacillus spore surrogate (B. thuringiensis or B. atrophaeus); (2) spore concentration in suspension (10{sup 2} to 10{sup 6} spores/ml); (3) chemical characteristics of decontaminant [sodium dicholor-s-triazinetrione dihydrate (Dichlor), hydrogen peroxide, potassium peroxymonosulfate (Oxone), sodium hypochlorite, and VirkonS{reg_sign}]; (4) decontaminant concentration (0.01% to 5%); and (5) decontaminant exposure time (10 min to 24 hr). Results from 162 suspension tests with appropriate controls are reported. Hydrogen peroxide at a concentration of 5%, and Dichlor and sodium hypochlorite at a concentration of 2%, were effective at spore inactivation regardless of spore type tested, spore exposure time, or spore concentration evaluated. This is the first reported study of Dichlor as an effective decontaminant for B. anthracis spore surrogates. Dichlor's desirable characteristics of high oxidation potential, high level of free chlorine, and more neutral pH than that of other oxidizers evaluated appear to make it an excellent alternative. All three oxidizers were effective against B. atrophaeus spores in meeting EPA's biocide standard of greater than a 6 log kill after a 10-minute exposure time and at lower concentrations than typically reported for biocide use. Solutions of 5% VirkonS{reg_sign} and Oxone were less effective decontaminants than other options evaluated in this study and did not meet the EPA's efficacy standard for biocides. Differences in methods and procedures reported by other investigators make quantitative comparisons among studies difficult.

  6. Skin decontamination of G, V, H L agents by Canadian reactive skin decontaminant lotion

    Energy Technology Data Exchange (ETDEWEB)

    Bide, R.W.; Sawyer, T.W.; DiNinno, V.L.; Armour, S.J.; Risk, D.J.

    1993-05-13

    The Canadian Reactive Skin Decontaminant Lotion (RSDL) is a reactive solution designed to be applied directly to skin for the decontamination and destruction of the classical chemical warfare agents. The solvent of the RSDL is very effective in dissolving liquid agents from the skin surface and the differential solubility of agents in the RSDL and the skin strongly favors retention of agents in the lotion. The active ingredient in the RSDL reacts rapidly and completely with G-agents, V-agents, mustard Lewisite producing relatively nontoxic products. The RSDL will dissolve and destroy agent thickened with acrylate polymers. The lotion is water soluble and readily removed from the skin. Since the RSDL is water soluble, it is active against water soluble agents even at high dilutions. For water insoluble agents, the activity is reduced as the water content rises above abrasive 50% due to insolubility of the agents. Skin and eye irritancy trials indicate that the RSDL is only a mild irritant to the eyes (equivalent to a chlorinated swimming pool) and to abraded skin. Acute toxicity trials showed that large oral and intraperitoneal doses were essentially non-toxic. The RSDL was fielded by the Canadian Forces for the Gulf Conflict. The RSDL may be used in open wounds for short periods. Wound decontamination and irrigation with RSDL diluted 1:1 with isotonic saline was recommended for the Gulf conflict.

  7. Comparative scrub solution tests for decontamination of transuranic radionuclides from soils

    International Nuclear Information System (INIS)

    Stevens, J.R.; Kochen, R.L.; Rutherford, D.W.; Riordan, G.A.; Delaney, I.C.

    1982-08-01

    Soil decontamination tests were done using three scrubbing solutions on five different transuranic-contaminated soils from Department of Energy sites. The soils came from Rocky Flats, Colorado; Hanford, Washington; Mound Facility, Ohio; Idaho National Engineering Laboratory, Idaho; and Los Alamos National Laboratory, New Mexico. Decontamination was effected by physical and chemical means. A pH 12.5 scrub effected decontamination by serving as a hydraulic grading and attrition scrub medium; this solution did not solubilize the actinide contamination. A 2% HNO 3 , 0.2% HF, 2% pine oil, and 5% Calgon solution effected decontamination by physical and chemical means; this solution solubilized particulate actinide and actinide dispersed on the surface of soil particles. A 2N HCl scrub was also used to effect decontamination by physical and chemical means; this reagent solubilized soil constituents, removing contamination that had migrated into mineral surfaces. Only Rocky Flats soil was effectively decontaminated by the high pH solution although all soils had an enrichment of the activity in the -150 mesh fraction. Attrition scrubbing with both acid solutions had a better decontamination ability for the +150 mesh fraction for Hanford, INEL, and LANL soils. In addition, the acid solutions solubilized some of the plutonium and had a decontamination effect on the fine fractions

  8. A State of the Art Report on the Case Study of Hot Cell Decontamination and Refurbishment

    Energy Technology Data Exchange (ETDEWEB)

    Won, H. J.; Jung, C. H.; Moon, J. K.; Park, G. I.; Song, K. C

    2008-08-15

    As the increase of the operation age of the domestic high radiation facilities such as IMEF, PIEF and DFDF, the necessity of decontamination and refurbishment of hot cells in these facilities is also increased. In the near future, the possibilities of refurbishment of hot cells in compliance with the new regulations, the reuse of hot cells for the other purposes and the decommissioning of the facilities also exist. To prepare against the decontamination and refurbishment of hot cells, the reports on the refurbishment, decommissioning and decontamination experiences of hot cells in USA, Japan, France, Belgium and Great Britain were investigated. ANL of USA performed the project on the decontamination of hot cells. The purpose of the project was to practically eliminate the radioactive emissions of Rn-220 to the environment and to restore the hot cells to an empty restricted use condition. The five hot cells were emptied and decontaminated for restricted use. Chemical processing facility in JAEA of Japan was used for the reprocessing study of spent fuels, hot cells in CPF were refurbished from 1995 for the tests of the newly developed reprocessing process. In a first stage, decommissioning and decontamination were fully performed by the remote operation Then, decommissioning and decontamination were performed manually. By the newly developed process, they reported that the radiation exposure of workers were satisfactorily reduced. In the other countries, they also make an effort for the refurbishment and decontamination of hot cells and it is inferred that they accumulate experiences in these fields.

  9. Mesoporous CuO–ZnO binary metal oxide nanocomposite for decontamination of sulfur mustard

    International Nuclear Information System (INIS)

    Praveen Kumar, J.; Prasad, G.K.; Ramacharyulu, P.V.R.K.; Garg, P.; Ganesan, K.

    2013-01-01

    Mesoporous CuO–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard, a well known chemical warfare agent. They were prepared by precipitation pyrolysis method and characterized by means of X-ray diffraction, transmission electron microscopy, nitrogen adsorption, Fourier transform infrared spectroscopy techniques. Obtained data indicated the presence of mesopores with diameter ranging from 2 to 80 nm and the materials exhibited relatively high surface area 86 m 2 g −1 when compared to the individual metal oxide nanoparticles. Reactive sites of mesoporous CuO–ZnO binary metal oxide nanocomposites were studied by infrared spectroscopy technique using pyridine as a probe molecule. These materials demonstrated superior decontamination properties against sulfur mustard when compared to single component metal oxides and decontaminated it to divinyl sulfide, chloroethyl vinyl sulfide, hemisulfur mustard, etc. - Graphical abstract: Mesoporous CuO–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard, a well known chemical warfare agent. These materials demonstrated superior decontamination properties against sulfur mustard and decontaminated it to divinyl sulfide, chloroethyl vinyl sulfide, hemisulfur mustard, etc. - Highlights: • Preparation of mesoporous CuO–ZnO binary metal oxide nanocomposite. • CuO–ZnO with better surface area was synthesized by precipitation pyrolysis. • Decontamination of HD using mesoporous CuO–ZnO binary metal oxide nanocomposite. • HD decontaminated by elimination and hydrolysis reactions

  10. Mesoporous CuO–ZnO binary metal oxide nanocomposite for decontamination of sulfur mustard

    Energy Technology Data Exchange (ETDEWEB)

    Praveen Kumar, J.; Prasad, G.K., E-mail: gkprasad2001@yahoo.com; Ramacharyulu, P.V.R.K.; Garg, P.; Ganesan, K.

    2013-11-01

    Mesoporous CuO–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard, a well known chemical warfare agent. They were prepared by precipitation pyrolysis method and characterized by means of X-ray diffraction, transmission electron microscopy, nitrogen adsorption, Fourier transform infrared spectroscopy techniques. Obtained data indicated the presence of mesopores with diameter ranging from 2 to 80 nm and the materials exhibited relatively high surface area 86 m{sup 2} g{sup −1} when compared to the individual metal oxide nanoparticles. Reactive sites of mesoporous CuO–ZnO binary metal oxide nanocomposites were studied by infrared spectroscopy technique using pyridine as a probe molecule. These materials demonstrated superior decontamination properties against sulfur mustard when compared to single component metal oxides and decontaminated it to divinyl sulfide, chloroethyl vinyl sulfide, hemisulfur mustard, etc. - Graphical abstract: Mesoporous CuO–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard, a well known chemical warfare agent. These materials demonstrated superior decontamination properties against sulfur mustard and decontaminated it to divinyl sulfide, chloroethyl vinyl sulfide, hemisulfur mustard, etc. - Highlights: • Preparation of mesoporous CuO–ZnO binary metal oxide nanocomposite. • CuO–ZnO with better surface area was synthesized by precipitation pyrolysis. • Decontamination of HD using mesoporous CuO–ZnO binary metal oxide nanocomposite. • HD decontaminated by elimination and hydrolysis reactions.

  11. A decontamination system for chemical weapons agents using a liquid solution on a solid sorbent.

    Science.gov (United States)

    Waysbort, Daniel; McGarvey, David J; Creasy, William R; Morrissey, Kevin M; Hendrickson, David M; Durst, H Dupont

    2009-01-30

    A decontamination system for chemical warfare agents was developed and tested that combines a liquid decontamination reagent solution with solid sorbent particles. The components have fewer safety and environmental concerns than traditional chlorine bleach-based products or highly caustic solutions. The liquid solution, based on Decon Greentrade mark, has hydrogen peroxide and a carbonate buffer as active ingredients. The best solid sorbents were found to be a copolymer of ethylene glycol dimethacrylate and n-lauryl methacrylate (Polytrap 6603 Adsorber); or an allyl methacrylate cross-linked polymer (Poly-Pore E200 Adsorber). These solids are human and environmentally friendly and are commonly used in cosmetics. The decontaminant system was tested for reactivity with pinacolyl methylphosphonofluoridate (Soman, GD), bis(2-chloroethyl)sulfide (Mustard, HD), and S-(2-diisopropylaminoethyl) O-ethyl methylphosphonothioate (VX) by using NMR Spectroscopy. Molybdate ion (MoO(4)(-2)) was added to the decontaminant to catalyze the oxidation of HD. The molybdate ion provided a color change from pink to white when the oxidizing capacity of the system was exhausted. The decontaminant was effective for ratios of agent to decontaminant of up to 1:50 for VX (t(1/2) decontamination solution were measured to show that the sorbent decreased the vapor concentration of GD. The E200 sorbent had the additional advantage of absorbing aqueous decontamination solution without the addition of an organic co-solvent such as isopropanol, but the rate depended strongly on mixing for HD.

  12. Polymeric compositions for “dry” decontamination of NPP equipment and premises

    International Nuclear Information System (INIS)

    Voronik, N.I.; Toropova, V.V.

    2015-01-01

    In JIPNR – “Sosny” NASB developed decontaminating polymeric compositions based on binder – polyvinyl alcohol solution with active additives such as nitric and borohydrofluoric acids, 1-hydroxyethylidene diphosphonic acid and its salts, detergents and fillers - natural tripoli; tripoli modified by ferrocyanides of nickel and copper; pulverized dolomite modified by manganese oxides, ferrocyanides of nickel and copper; clinoptilolite modified by iron chlorides (III) and calcium sodium phosphate and potassium ferrocyanide; hydrolytic lignin. It is shown that the developed decontaminating polymeric compositions (pastes) possess high decontaminating capacity (FD 102 – 103) and low adhesion to the surfaces of stainless and carbon steels, including painted, plastic, self-leveling floors, teflon-surface. Prolonged leaching method allowed determine the chemical resistance of “dry” decontamination wastes, strength of "1"3"7Cs and "6"0Co fixations in wastes obtained in result of using new decontamination pastes [ru

  13. Chemical, biological, radiological, and nuclear decontamination: Recent trends and future perspective

    Directory of Open Access Journals (Sweden)

    Vinod Kumar

    2010-01-01

    Full Text Available Chemical, biological, radiological, and nuclear (CBRN decontamination is the removal of CBRN material from equipment or humans. The objective of the decontamination is to reduce radiation burden, salvage equipment, and materials, remove loose CBRN contaminants, and fix the remaining in place in preparation for protective storage or permanent disposal work activities. Decontamination may be carried out using chemical, electrochemical, and mechanical means. Like materials, humans may also be contaminated with CBRN contamination. Changes in cellular function can occur at lower radiation doses and exposure to chemicals. At high dose, cell death may take place. Therefore, decontamination of humans at the time of emergency while generating bare minimum waste is an enormous task requiring dedication of large number of personnel and large amount of time. General principles of CBRN decontamination are discussed in this review with emphasis on radiodecontamination.

  14. Survey of decontamination and decommissioning techniques

    International Nuclear Information System (INIS)

    Kusler, L.E.

    1977-01-01

    Reports and articles on decommissioning have been reviewed to determine the current technology status and also attempt to identify potential decommissioning problem areas. It is concluded that technological road blocks, which limited decommissioning facilities in the past have been removed. In general, techniques developed by maintenance in maintaining the facility have been used to decommission facilities. Some of the more promising development underway which will further simplify decommissioning activities are: electrolytic decontamination which simplifies some decontaminating operations; arc saw and vacuum furnace which reduce the volume of metallic contaminated material by a factor of 10; remotely operated plasma torch which reduces personnel exposure; and shaped charges, water cannon and rock splitters which simplify concrete removal. Areas in which published data are limited are detailed costs identifying various components included in the total cost and also the quantity of waste generated during the decommissioning activities. With the increased awareness of decommissioning requirements as specified by licensing requirements, design criteria for new facilities are taking into consideration final decommissioning of buildings. Specific building design features will evolve as designs are evaluated and implemented

  15. Factors Associated with Absenteeism in High Schools

    OpenAIRE

    DEMIR, Kamile; AKMAN KARABEYOGLU, Yasemin

    2016-01-01

    Problem Statement: There are many factors that affect student achievement directly and indirectly at the secondary educational level. Lower attendance rates have been cited as detrimental to academic achievement; therefore, it is suggested that improved attendance is a direct indicator, rather than determinant of students’ academic achievement.Purpose of Study: The main purpose of this study was to investigate the effect of individual, family and school variables on absenteeism among high sch...

  16. Verification of wet blasting decontamination technology

    International Nuclear Information System (INIS)

    Matsubara, Sachito; Murayama, Kazunari; Yoshida, Hirohisa; Igei, Shigemitsu; Izumida, Tatsuo

    2013-01-01

    Macoho Co., Ltd. participated in the projects of 'Decontamination Verification Test FY 2011 by the Ministry of the Environment' and 'Decontamination Verification Test FY 2011 by the Cabinet Office.' And we tested verification to use a wet blasting technology for decontamination of rubble and roads contaminated by the accident of Fukushima Daiichi Nuclear Power Plant of the Tokyo Electric Power Company. As a results of the verification test, the wet blasting decontamination technology showed that a decontamination rate became 60-80% for concrete paving, interlocking, dense-grated asphalt pavement when applied to the decontamination of the road. When it was applied to rubble decontamination, a decontamination rate was 50-60% for gravel and approximately 90% for concrete and wood. It was thought that Cs-134 and Cs-137 attached to the fine sludge scraped off from a decontamination object and the sludge was found to be separated from abrasives by wet cyclene classification: the activity concentration of the abrasives is 1/30 or less than the sludge. The result shows that the abrasives can be reused without problems when the wet blasting decontamination technology is used. (author)

  17. Decontamination and decommissioning of the West Valley Reprocessing Plant

    International Nuclear Information System (INIS)

    Daugherty, H.F.; Keel, R.

    1986-11-01

    This report presents the decontamination and decommissioning (D and D) activities at the West Valley Nuclear Fuel Reprocessing Plant through September 1, 1986. The topics addressed are: D and D of areas for reuse by the Liquid Waste Treatment System (LWTS); D and D of areas for reuse as High Level Waste (HLW) canister storage; and technologies developed in D and D work

  18. New decontamination techniques generating a low volume of effluent

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This document presents some decontamination techniques, their principles, characteristics and advantages and provides references on the subject. Techniques as foam and spray foam decontamination, dry steam decontamination, electro-decontamination and gel decontamination are presented. A presentation of TRIADE, cleanup dismantling servicing, is also provided. (A.L.B.)

  19. New decontamination techniques generating a low volume of effluent

    International Nuclear Information System (INIS)

    2002-01-01

    This document presents some decontamination techniques, their principles, characteristics and advantages and provides references on the subject. Techniques as foam and spray foam decontamination, dry steam decontamination, electro-decontamination and gel decontamination are presented. A presentation of TRIADE, cleanup dismantling servicing, is also provided. (A.L.B.)

  20. Decontamination of radionuclides in food

    Energy Technology Data Exchange (ETDEWEB)

    Ohmomo, Yoichiro [Institute for Environmental Sciences, Aomori (Japan)

    1994-03-01

    The release of radionuclides arising from the Chernobyle accident led to widespread contamination of the northern hemisphere through fallout. This accident provided again an opportunity to investigate how and to what extent the radionuclides contamination in crops and animal derived foods could be reduced. The following topics are included in this paper. (1) How to reduce the transfer of radiostrontium and/or cesium from soil to crops: A pH increase of soil is effective for reducing their plant uptake. (2) How to reduce the transfer of radiocesium to animal derived foods: Ammonium-ferric-cyanoferrate (AFCF) should be the most effective compound for radiocesium excretion in the feces. Experiments with lactating cows and/or poultry gave extremely good results with respect to low radiocesium concentrations in milk, meat and eggs. (3) Removal coefficients of radiostrontium, cesium and iodine from contaminated leaf vegetables and cereals during food processing and culinary preparation: Though different by species, more than 80% of cesium and about 50% of strontium and iodine can be removed during culinary preparation of washing and boiling. (4) Simultaneous decontamination of radiocesium and iodine from drinking water and liquid milk: Metal ferrocyanide-anion exchange resin, specifically Fe ferrocyanide one, was successfully used for a rapid and simple decontamination of radiocesium and iodine in the liquid samples arising from the Chernobyle accident. (5) Removal of radiocesium from meat: The meat structurally contaminated with radiocesium is easily and very successfully decontaminated by pickling in NaCl solution and the decontamination is much speeded up by freezing meat before pickling. (author).

  1. Skin contamination - prevention and decontaminating

    International Nuclear Information System (INIS)

    Henning, K.

    2001-01-01

    A detailed examination is made of the structure of human skin. Measures were drawn up to prevent skin contamination in nuclear installations as well as contaminated skin was decontaminated from the personnel. By systematically applying these measures a significant level of success was achieved in preventing contamination in nuclear installations. Cases where more far-reaching chemical methods had to be used were kept to a minimum. (R.P.)

  2. Chemical decontamination of reactor components

    International Nuclear Information System (INIS)

    Riess, R.; Berthold, H.O.

    1977-08-01

    A solution for the decontamination of reactor components of the primary system was developed. This solution is a modification of the APAC- (Alkaline Permanganate Ammonium Citrate) system described in the literature. The most important advantage of the present solution over the APAC-method is that it does not induce any selective corrosion attack on materials like stainless steel (austenitic), Inconel 600 and Incoloy 800. (orig.) [de

  3. Decontamination of radionuclides in food

    International Nuclear Information System (INIS)

    Ohmomo, Yoichiro

    1994-01-01

    The release of radionuclides arising from the Chernobyle accident led to widespread contamination of the northern hemisphere through fallout. This accident provided again an opportunity to investigate how and to what extent the radionuclides contamination in crops and animal derived foods could be reduced. The following topics are included in this paper. (1) How to reduce the transfer of radiostrontium and/or cesium from soil to crops: A pH increase of soil is effective for reducing their plant uptake. (2) How to reduce the transfer of radiocesium to animal derived foods: Ammonium-ferric-cyanoferrate (AFCF) should be the most effective compound for radiocesium excretion in the feces. Experiments with lactating cows and/or poultry gave extremely good results with respect to low radiocesium concentrations in milk, meat and eggs. (3) Removal coefficients of radiostrontium, cesium and iodine from contaminated leaf vegetables and cereals during food processing and culinary preparation: Though different by species, more than 80% of cesium and about 50% of strontium and iodine can be removed during culinary preparation of washing and boiling. (4) Simultaneous decontamination of radiocesium and iodine from drinking water and liquid milk: Metal ferrocyanide-anion exchange resin, specifically Fe ferrocyanide one, was successfully used for a rapid and simple decontamination of radiocesium and iodine in the liquid samples arising from the Chernobyle accident. (5) Removal of radiocesium from meat: The meat structurally contaminated with radiocesium is easily and very successfully decontaminated by pickling in NaCl solution and the decontamination is much speeded up by freezing meat before pickling. (author)

  4. Radiation decontamination of poultry viscera

    International Nuclear Information System (INIS)

    Jamdar, S.N.; Harikumar, P.

    2008-01-01

    Application of gamma radiation for decontamination of poultry viscera was examined. Exposure to a dose of 20 kGy rendered the viscera sterile ( 10 cycles, respectively, eliminating the coliforms to o C) produced enhanced levels of TVBN and TCA soluble products accompanied by higher drip loss. Activities of proteolytic enzymes, except acid protease, did not show any significant change during post-irradiation storage at either temperature

  5. The need for forest decontamination: for the recovery of Fukushima

    International Nuclear Information System (INIS)

    Orita, Makiko; Fukushima, Yoshiko; Takamura, Noboru; Shunichi Yamashita

    2017-01-01

    After the accident at the Fukushima Daiichi Nuclear Power Station (FDNPS) in 2011, the residential areas within the evacuation order areas around FDNPS were extensively decontaminated, but the need for forest decontamination remains controversial. Almost 70% of Fukushima prefecture is covered by forest, and forestry is one of the key industries there. From the perspective of forestry recovery and environmental preservation, Fukushima residents desire the further decontamination of forests; from the perspective of cost-effectiveness and priorities, however, this has both pros and cons(1). Bearing in mind the need to discuss priorities regarding the decontamination of forest, therefore, a radiation dose evaluation of foresters working in the FDNPS vicinity is important. This paper reports on the measurement of individual radiation doses by occupation in Kawauchi village (Figure 1a), which is located within 30 km from the FDNPS(2, 3), using the personal dosimeter (D-Shuttle"R, Chiyoda Technol Corp, Tokyo, Japan). Our results showed that estimated annual doses of 1.19 mSv/year (median) with a range of 0.71 1.89 among foresters, 0.97 (0.66 1.48) mSv/year for farmers, 0.94 (0.59 1.51) mSv/year for builders, 0.88 (0.54 1.48) mSv/year for officers, 1.01 (0.55 1.75) mSv/year for unemployed individuals and 0.98 (0.54 7.07) mSv/ year for decontamination workers (Figure 1b). Thus, the annual doses of foresters was not significantly higher than farmers, builders, officers and unemployed individuals, whereas those of decontamination workers were significantly higher than for other workers, including foresters, suggesting that in terms of protecting foresters from radiation, forest decontamination is not a high-priority policy in Fukushima. The International Commission on Radiological Protection (ICRP) recommends that for the protection of residents living in radio-contaminated areas during the recovery process, the justification of protection strategies goes far beyond the scope

  6. Development of new chemical and electrochemical decontamination methods for selected equipment of WWER-440 and WWER-1000 reactor primary circuit

    International Nuclear Information System (INIS)

    Solcanyi, M.; Majersky, D.

    1998-01-01

    Special devices for in-situ application of decontamination technologies assigned for Steam Generator, Pressurizer and Main Circulating Casing of WWER-1000 type were designed, manufactured and tested in real conditions of their use in above Primary Circuit components. New decontamination technologies like low-concentration process NP-NHN for the decontamination of the Steam Generator, combined chemico-mechanical treatment for the Pressurizer and semi-dry electrolysis for the Main Circulating Pump Casing were developed and approved for their safe plant application from point of view of decontamination efficiency, corrosion influence and processing of secondary wastes. Main technological parameters were defined to achieve high decontamination efficiency and corrosion-safe application of all decontamination technologies. (author)

  7. Evaluation of the efficacy of decontamination methods examined at Japanese garden located in Chiba Prefectural Kashiwa-no-ha Park

    International Nuclear Information System (INIS)

    Ichikawa, Yujiro; Inoue, Tomohiro; Naito, Suekazu; Takahashi, Yoshihiko

    2014-01-01

    The efficacy of decontamination methods was evaluated with the measurement of 1cm dose equivalent rate and concentration of radioactive caesium in the soil, plants and water of the pond before and after decontamination at Japanese garden located in Chiba Prefectural Kashiwa-no-ha Park. Examined decontamination methods were: 1) The topsoil of walkway was stripped and removed to the depth of 10mm. 2) Washing the stone pavement walkway using high-pressure water jet washer. At the height of 50cm, we observed 45% and 36% of 1cm dose rate equivalent dose reduction rate (the natural dose rate derived from the ground was subtracted) for 1) and 2) decontamination methods respectively. Due to the decontamination process, the measurement value of 1cm equivalent dose rate decreased below 0.23μSv/h at most of the examined sites, which showed significant efficacy of decontamination methods performed at this Japanese garden. (author)

  8. Decontamination experience using the EMMAC process in EDF nuclear power plants

    International Nuclear Information System (INIS)

    Noel, D.; Spychala, H. B.; Dupin, M.; Lantes, B.; Goulain, F.; Gregoire, J.; Jeandrot, S.

    1997-01-01

    The EMMA, EMMAC and EMMAC-PLUS decontamination processes, nondestructive tests and waste treatment are presented. The various applications of the new EMMAC soft decontamination process, used by EDF since 1995 have shown that it is a very effective tool and at the same time, is a very low corrosive process for the materials that have been treated . The improved efficiency, compared to the previous EMMA process allowed us to obtain good decontamination factors with only one cycle instead of two. At the same time, changes in chemical composition and waste treatment produced large reduction in the amount of radioactive wastes generated. Further improvements are still being sought. (authors)

  9. ORO scrap metal decontamination program

    International Nuclear Information System (INIS)

    Jugan, M.

    1987-01-01

    The Oak Ridge Operations Office (ORO) of the US Department of Energy (DOE) has approximately 80,000 tons of contaminated scrap metal at the Oak Ridge Gaseous Diffusion Plant in Oak Ridge, Tennessee; Paducah Gaseous Diffusion Plant in Paducah, Kentucky; Portsmouth Gaseous Diffusion Plant in Piketon, Ohio; and the Feed Materials Production Center in Fernald, Ohio. After unsuccessful in-house attempts to eliminate/recycle the contaminated metal, DOE is allowing private enterprise the opportunity to participate in this program. DOE is making this opportunity available under a two-phase approach, which is being supported by two separate and corresponding Request for Proposals. Phase I, which is nearing completion, is a demonstration phase to establish a group of companies that the DOE will consider qualified to eliminate the scrap at one or more sites. In Phase I, the companies decontaminated 25-50 tons of scrap to demonstrate capabilities to DOE and to gain the knowledge required to plan/bid on elimination of the scrap at one or more sites. Phase II will request proposals for elimination of the total scrap at one or more of the above noted sites. Multiple awards for Phase II are also anticipated. Companies participating in Phase II will be required to take title to the contaminated scrap and decontaminate/process the scrap for beneficial reuse. Radioactive wastes and metal that cannot be successfully decontaminated/processed will be returned to DOE

  10. Elimination device for decontaminated surface layers

    International Nuclear Information System (INIS)

    Yoshikawa, Kozo.

    1983-01-01

    Purpose: To conduct efficient decontamination injecting solid carbon dioxide particles at a high speed by using a simple and compact device. Constitution: Liquid carbon dioxide is injected from a first vessel containing liquid carbon dioxide by way of a carbon dioxide supply tube to a solid carbon dioxide particle jetting device. The liquid carbon dioxide is partially converted into fine solid carbon dioxide particles due to the temperature reduction caused by adiabatic expansion of the gaseous carbon dioxide in an expansion space for the gaseous carbon dioxide formed in the jetting device and arrives at a solid carbon dioxide injection nozzle in communication with the expansion space. Then, the fine solid carbon dioxide particles are further cooled and accelerated by the nitrogen gas jetted out from a nitrogen gas nozzle at the top of a nitrogen gas supply tube in communication with a second vessel containing liquid nitrogen disposed within the nozzle, and jetted out from the solid carbon dioxide injection nozzle to collide against the surface to be decontaminated and eliminate the surface contamination. (Seki, T.)

  11. CO2 pellet blasting literature search and decontamination scoping tests report

    International Nuclear Information System (INIS)

    Archibald, K.E.

    1993-12-01

    Past decontamination and solvent recovery activities at the Idaho Chemical Processing Plant (ICPP) have resulted in the accumulation of 1.5 million gallons of radioactively contaminated sodium-bearing liquid waste. Future decontamination activities at the ICPP could result in the production of 5 million gallons or more of sodium-bearing waste using current decontamination techniques. Chemical decontamination flushes have provided a satisfactory level of decontamination. However, this method generates large amounts of sodium-bearing secondary waste. Steam jet cleaning has also been used with a great deal of success but cannot be used on concrete or soft materials. With the curtailment of reprocessing at the ICPP, the focus of decontamination is shifting from maintenance for continued operation of the facilities to decommissioning. Treatment of sodium-bearing waste is a particularly difficult problem due to the high content of alkali metals in the sodium-bearing liquid waste. It requires a very large volume of cold chemical additive for calcination. In addition, the sodium content of the sodium-bearing waste exceeds the limit that can be incorporated into vitrified waste without the addition of glass-forming compounds (primarily silicon) to produce an acceptable immobilized waste form. The primary initiatives of the Decontamination Development Program is the development of methods to eliminate/minimize the use of sodium-bearing decontamination chemicals and to minimize all liquid decontamination wastes. One method chosen for cold scoping studies during FY-93 was CO 2 pellet blasting. CO 2 pellet blasting has been used extensively by commercial industries for general cleaning. However, using this method for decontamination of nuclear materials is a fairly new concept. The following report discusses the research and scoping tests completed on CO 2 pellet blasting

  12. Decontamination of burns contaminated with radioactive materials

    International Nuclear Information System (INIS)

    Vykouril, L.

    1986-01-01

    The suitability of various solutions for the decontamination of burnt skin and their efficiency were tested by experiments on rats. Tested was the decontamination of undisturbed skin, second degree skin burns and third degree skin burns. Decontamination solutions used included: distilled water, jodonal (an aqueous solution of iodine, ethoxylated nonylphenols, the copolymer of ethylene oxide with propylene oxide, and phosphoric acid) and a decontamination mixture of Sapon, Komplexon (trade names of detergents) and sodium hexametaphosphate. Decontamination efficiency was 68.4% for second degree burns and 47.1% for third degree burns. Most effective was the decontamination solution with an efficiency of 72%; the efficiency of jodonal was 67% and of water - 54%. Jodonal is the most suitable: in addition, it acts as a disinfectant and antiseptic. (M.D.)

  13. The efficiency of superficially active compounds on the process of decontamination in animals exposed to various doses of ionizing radiation

    International Nuclear Information System (INIS)

    Kossakowski, S.

    1977-01-01

    The efficiency of some superficially active compounds on the process of decontamination was investigated in swine exposed to various doses of ionizing radiation (300, 600 R), and then contaminated with 90 Sr, 131 I, 137 Cs, and 144 Ce. The results revealed that the time factor after irradiation was more important for the efficiency of decontamination than the doses of radiation. (author)

  14. UK fast reactor components. Sodium removal decontamination and requalification

    International Nuclear Information System (INIS)

    Donaldson, D.M.; Bray, J.A.; Newson, I.H.

    1978-01-01

    Extensive experience gained at the U.K.A.E.A. Dounreay Nuclear Power Development Establishment is being applied to form the basis of the plant to be provided for sodium removal, decontamination, and requalification of components in future commercial fast reactors. In the first part of a three part paper, the factors to be taken into account, showing the UK philosophy and approach to maintenance and repair operations are discussed. In the second part, PFR facilities for sodium removal and decontamination are described and some examples are given of cleaning components such as pumps, charge machine, cold trap baskets, and steam generator units. Similar facilities at DFR are briefly described. In the third part of the paper a short description is given of the Harwell mass transfer loop, currently used to study the deposition of activated stainless steel corrosion products. Decontamination method for pipework specimens cut from the loop are described and results of first screening tests of various chemical decontaminants are presented. (U.K.)

  15. Evaluation of laryngoscopes decontamination practices in different hospitals

    International Nuclear Information System (INIS)

    Ahmad, M.; Hussain, W.; Saleem, A.; Saqib, M

    2014-01-01

    To find disinfection and sterilization practices of laryngoscope in different hospitals. Study Design: Descriptive study. Materials and Methods: Laryngoscope decontamination practices in different hospitals were evaluated in this study which was based on a telephonic structured questionnaire. Preset questions were asked on phone from operation room technicians of 50 different hospitals. For clarification and confirmation of procedure anesthesiologist of the hospital was contracted. Laryngoscope decontamination practices were asked as per questionnaire and data collected was recorded and analyzed. Results were documented and compared with studies regarding laryngoscope decontamination practices of different countries. Results: Most exercised methods were manual decontamination with simple gauze (50%), alcohol gauze (11%) or tap water (27%). The use of disposable blades and sheathing of blades was not practiced by any of the hospitals. Similarly chemical disinfectants were used rarely (2%). Rinsing laryngoscopes with water (always 27%, sometimes 23%) was very common while, autoclaving or sheathing of blades was not done in any of the hospital. Conclusion: The rate of different postoperative infection is on the increase in our hospitals and one likely contributing source is contaminated laryngoscopes. Lack of awareness and poor practices among health care professionals, over work and economic constraints are the major contributing factors which need to be controlled by adhering to international standards. (author)

  16. EDF/CIDEN - ONECTRA: PWR decontamination

    International Nuclear Information System (INIS)

    Fayolle, P.; Orcel, H.; Wertz, L.

    2010-01-01

    In the context of PWR circuit renewal (expected in 2011) and their decontamination, an analysis of data coming from cartography and on site decontamination measurements as well as from premise modelling by means of the PANTHERE radioprotection code, is presented. Several French PWRs have been studied. After a presentation of code principles and operation, the authors discuss the radiological context of a workstation, and give an assessment of the annual dose associated with maintenance operations with or without decontamination

  17. Geographic assistance of decontamination strategy elaboration

    International Nuclear Information System (INIS)

    Davydchuk, V.; Arapis, G.

    1996-01-01

    Those who elaborates the strategy of decontamination of vast territories is to take into consideration the heterogeneity of such elements of landscape as relief, lithology, humidity and types of soils and, vegetation, both on local and regional level. Geographic assistance includes evaluation of efficacy of decontamination technologies in different natural conditions, identification of areas of their effective application and definition of ecological damage, estimation of balances of the radionuclides in the landscapes to create background of the decontamination strategy

  18. Decontamination training: with and without virtual reality simulation.

    Science.gov (United States)

    Farra, Sharon Lee; Smith, Sherrill; Gillespie, Gordon Lee; Nicely, Stephanie; Ulrich, Deborah L; Hodgson, Eric; French, DeAnne

    2015-01-01

    Nurses must be prepared to care for patients following a disaster, including patients exposed to hazardous contaminants. The purpose of this study was to examine the use of virtual reality simulation (VRS) to teach the disaster-specific skill of decontamination. A quasi-experimental design was used to assign nursing students from 2 baccalaureate nursing programs to 1 of 2 groups to learn the disaster skill of decontamination-printed written directions or VRS. Performance, knowledge, and self-efficacy were outcome measures. Although students in the treatment group had significantly lower performance scores than the control group (p = 0.004), students taking part in VRS completed the skill in a significantly shorter amount of time (p = 0.008). No significant group differences were found for self-efficacy (p = 0.172) or knowledge (p = 0.631). However, students in the VRS treatment group reported high levels of satisfaction with VRS as a training method. The disaster-specific skill of decontamination is a low-volume, high-risk skill that must be performed with accuracy to protect both exposed patients and providers performing decontamination. As frontline providers for casualties following a disaster event, emergency nurses must be prepared to perform this skill when needed. Preparation requires cost-effective, timely, and evidence-based educational opportunities that promote positive outcomes. Further investigation is needed to determine the benefits and long-term effects of VRS for disaster education.

  19. Theory of soil decontamination in mixing liquid

    International Nuclear Information System (INIS)

    Polyakov, A.S.; Emets, E.P.; Poluehktov, P.P.; Rybakov, K.A.

    1997-01-01

    The theory of soil decontamination from radioactive pollution in mixing liquid flow is described. It is shown that there exists the threshold intensity of liquid mixing up to which there is no decontamination. Beyond the threshold and by increasing the mixing intensity the decontamination of large soil fractions is allowable whereby the higher is the mixing intensity and lower is the soil contamination, the laser is the characteristic decontamination time. The above theory is related to cases of uniform pollution of the particles surface

  20. Decontamination and decommissioning techniques for research reactors

    International Nuclear Information System (INIS)

    Oh, Won Zin; Won, H. J.; Jung, C. H.; Choi, W. K.; Kim, G. N.; Lee, K. W.

    2002-05-01

    Evaluation of soil decontamination process and the liquid decontamination waste treatment technology are investigation of organic acid as a decontamination agent, investigation of the liquid waste purification process and identification of recycling the decontamination agents. Participation on IAEA CRP meeting are preparation of IAEA technical report on 'studies on decommissioning of TRIGA reactors and site restoration technologies' and exchange the research result, technology, experience and safety regulation of the research reactor D and D of USA, Great Britain, Canada, Belgium, Italy, India and so forth

  1. Method for decontaminating radiation metal waste

    International Nuclear Information System (INIS)

    Onuma, Tsutomu; Tanaka, Akio; Akimoto, Hidetoshi

    1991-01-01

    This report describes a method for decontaminating radiation metal waste characterized by the following properties: in order to decontaminate radiation metal waste of various shapes produced by facilities involved with radioactive substances, non-complex shapes are decontaminated by electropolishing the materials in a neutral saline solution. Complex shapes are chemically decontaminated by means of an acid solution containing permanganic acid or an alkaline solution and a mineral acid solution. After neutralizing the solutions used for chemical decontamination, the radioactive material is separated and removed. Further, in the decontamination method for radioactive metal waste, a supernatant liquid is reused as the electrolyte in electropolishing decontamination. Permanganic ions (MnO 4 - ) are reduced to manganese dioxide (MnO 2 ) and deposited prior to neutralizing the solution used for chemical decontamination. Once manganese dioxide (MnO 2 ) has been separated and removed, it is re-used as the electrolyte in electropolishing decontamination by means of a process identical to the separation process for radioactive substances. 3 figs

  2. Proceedings of the concrete decontamination workshop

    International Nuclear Information System (INIS)

    Halter, J.M.; Sullivan, R.G.; Currier, A.J.

    1980-09-01

    Fourteen papers were presented. These papers describe concrete surface removal methods and equipment, as well as experiences in decontaminating and removing both power and experimental nuclear reactors

  3. Decontamination and size reduction of plutonium contaminated process exhaust ductwork and glove boxes

    International Nuclear Information System (INIS)

    LaFrate, P.; Elliott, J.; Valasquez, M.

    1996-01-01

    The Los Alamos National Laboratory (LANL) Decommissioning Program has decontaminated and demolished two filter plenum buildings at Technical Area 21 (TA-21). During the project a former hot cell was retrofitted to perform decontamination and size reduction of highly Pu contaminated process exhaust (1,100 ft) and gloveboxes. Pu-238/239 concentrations were as high a 1 Ci per linear foot and averaged approximately 1 mCi/ft. The Project decontamination objective was to reduce the plutonium contamination on surfaces below transuranic levels. If possible, metal surfaces were decontaminated further to meet Science and Ecology Group (SEG) waste classification guidelines to enable the metal to be recycled at their facility in oak Ridge, Tennessee. Project surface contamination acceptance criteria for low-level radioactive waste (LLRW), transuranic waste, and SEG waste acceptance criteria will be presented. Ninety percent of all radioactive waste for the project was characterized as LLRW. Twenty percent of this material was shipped to SEG. Process exhaust and glove boxes were brought to the project decontamination area, an old hot cell in Building 4 North. This paper focuses on process exhaust and glovebox decontamination methodology, size reduction techniques, waste characterization, airborne contamination monitoring, engineering controls, worker protection, lessons learned, and waste minimization. Decontamination objectives are discussed in detail

  4. Decontamination of surfaces (1961); La decontamination des surfaces (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Mestre, E [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1961-07-01

    The continued expansion of atomic Energy has led the S.C.R.G.R. to extend simultaneously the recovery of materials contaminated by use in radio-active media. The importance of this aspect of atomic Energy was not immediately obvious to those concerned but is now fully recognized due to the cost of the materials and installations, and also to the time required for the construction of special equipment for the C.E.A. Another very important reason is the dangers associated with the handling of contaminated material. The S.C.R.G.R. attacked this problem from the point of view of these dangers. It later became apparent to the users, once the decontamination methods had proved their worth, that the process presented advantages from the material and cost-saving point of view. (author) [French] Le developpement toujours croissant de l'Energie atomique a conduit le S.C.R.G.R. a developper parallelement la recuperation des materiels contamines par leur emploi en milieu radioactif. Cet aspect de l'Energie atomique n'est pas apparu des le debut aux utilisateurs mais s'est tres vite impose etant donne, d'une part, le cout des installations et du materiel, d'autre part le temps necessaire a la fabrication d'un materiel special aux travaux du C.E.A., enfin et surtout, les risques associes a la manipulation d'un materiel contamine. Les risques seuls ont ete pris comme point de depart a l'examen de ce probleme par le S.C.R.G.R. puis avec le temps, les methodes de decontamination ayant fait leur preuve, les utilisateurs ont alors apercu les aspects materiels et la rentabilite de la decontamination. (auteur)

  5. Development of Nuclear Decontamination Technology Using Supercritical Fluid

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Wonyoung; Park, Kwangheon; Park, Jihye; Lee, Donghee [Kyunghee Univ., Yongin (Korea, Republic of)

    2014-05-15

    Soil cleaning technologies that have been developed thus far increase treatment costs in contaminated soil recovery processes because they generate large amounts of secondary wastes. In this respect, this study is intended to develop soil decontamination methods using CO{sub 2}, which is a nontoxic, environmentally friendly substance, in order to fundamentally suppress the generation of secondary wastes from the decontamination process and to create high added values. In this study, to develop decontamination methods for uranium-contaminated soil using supercritical CO{sub 2}, a soil decontamination system using supercritical CO{sub 2} was constructed. In addition, the basic principle of supercritical CO{sub 2} decontamination using a TBP-HNO3 complex was explained. According to the results of the study, sea-sand samples having the same degree of contamination showed different results of decontamination according to the quantities of the TBP-HNO3 complex used as an extraction agent, which resulted in high extraction rates. Thus far, a most widely used method of extracting uranium has been the dissolving of uranium in acids. However, this method has the large adverse effect of generating strong acidic wastes that cannot be easily treated. On the other hand, supercritical CO{sub 2} requires critical conditions that are no more difficult to meet than those of other supercritical fluids, since its density can be changed from a very low state close to that of an ideal gas to a high state close to that of liquids. The critical gas conditions are a pressure of 71 bar and a temperature of 31 .deg. C, both of which are inexpensive to achieve. Moreover, CO{sub 2} is a solvent that is not harmful to the human body and few effects on environmental pollution. Therefore, nontoxic and environment friendly processes can be developed using supercritical CO{sub 2}. Supercritical CO{sub 2}'s advantages over prevailing methods suggest its potential for developing innovative

  6. Low level radioactive liquid waste decontamination by electrochemical way

    International Nuclear Information System (INIS)

    Tronche, E.

    1994-10-01

    As part of the work on decontamination treatments for low level radioactive aqueous liquid wastes, the study of an electro-chemical process has been chosen by the C.E.A. at the Cadarache research centre. The first part of this report describes the main methods used for the decontamination of aqueous solutions. Then an electro-deposition process and an electro-dissolution process are compared on the basis of the decontamination results using genuine radioactive aqueous liquid waste. For ruthenium decontamination, the former process led to very high yields (99.9 percent eliminated). But the elimination of all the other radionuclides (antimony, strontium, cesium, alpha emitters) was only favoured by the latter process (90 percent eliminated). In order to decrease the total radioactivity level of the waste to be treated, we have optimized the electro-dissolution process. That is why the chemical composition of the dissolved anode has been investigated by a mixture experimental design. The radionuclides have been adsorbed on the precipitating products. The separation of the precipitates from the aqueous liquid enabled us to remove the major part of the initial activity. On the overall process some operations have been investigated to minimize waste embedding. Finally, a pilot device (laboratory scale) has been built and tested with genuine radioactive liquid waste. (author). 77 refs., 41 tabs., 55 figs., 4 appendixes

  7. Metal decontamination for waste minimization using liquid metal refining technology

    International Nuclear Information System (INIS)

    Joyce, E.L. Jr.; Lally, B.; Ozturk, B.; Fruehan, R.J.

    1993-01-01

    The current Department of Energy Mixed Waste Treatment Project flowsheet indicates that no conventional technology, other than surface decontamination, exists for metal processing. Current Department of Energy guidelines require retrievable storage of all metallic wastes containing transuranic elements above a certain concentration. This project is in support of the National Mixed Low Level Waste Treatment Program. Because of the high cost of disposal, it is important to develop an effective decontamination and volume reduction method for low-level contaminated metals. It is important to be able to decontaminate complex shapes where surfaces are hidden or inaccessible to surface decontamination processes and destruction of organic contamination. These goals can be achieved by adapting commercial metal refining processes to handle radioactive and organic contaminated metal. The radioactive components are concentrated in the slag, which is subsequently vitrified; hazardous organics are destroyed by the intense heat of the bath. The metal, after having been melted and purified, could be recycled for use within the DOE complex. In this project, we evaluated current state-of-the-art technologies for metal refining, with special reference to the removal of radioactive contaminants and the destruction of hazardous organics. This evaluation was based on literature reports, industrial experience, plant visits, thermodynamic calculations, and engineering aspects of the various processes. The key issues addressed included radioactive partitioning between the metal and slag phases, minimization of secondary wastes, operability of the process subject to widely varying feed chemistry, and the ability to seal the candidate process to prevent the release of hazardous species

  8. Radiation decontamination of dry food ingredients and processing aids

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, J

    1984-01-01

    Radiation decontamination of dry ingredients, herbs and enzyme preparations is a technically feasible, economically viable and safe physical process. The procedure is direct, simple, requires no additives and is highly efficient. Its dose requirement is moderate. Radiation doses of 3-10 kGy (0.3-1 mrad) have proved sufficient to reduce the viable counts to a satisfactory level. Ionising radiations do not cause any significant rise in temperature. The flavour, texture or other important technological or sensory properties of most ingredients are not influenced at radiation doses necessary for satisfactory decontamination, and radiation obviates the chemical residue problem. The microflora surviving radiation decontamination of dry ingredients are more susceptible to subsequent antimicrobial treatments. Recontamination can be prevented as the product can be irradiated in its final packaging. Irradiation could be carried out in commercial containers and would result in considerable savings of energy and labour as compared to alternative decontamination techniques. Radiation processing of these commodities is an established technology in several countries and more clearances on irradiated foods are expected to be granted in the near future.

  9. Advanced technologies for decontamination and conversion of scrap metal

    International Nuclear Information System (INIS)

    MacNair, V.; Muth, T.; Shasteen, K.; Liby, A.; Hradil, G.; Mishra, B.

    1996-01-01

    In October 1993, Manufacturing Sciences Corporation was awarded DOE contract DE-AC21-93MC30170 to develop and test recycling of radioactive scrap metal (RSM) to high value and intermediate and final product forms. This work was conducted to help solve the problems associated with decontamination and reuse of the diffusion plant barrier nickel and other radioactively contaminated scrap metals present in the diffusion plants. Options available for disposition of the nickel include decontamination and subsequent release or recycled product manufacture for restricted end use. Both of these options are evaluated during the course of this research effort. work during phase I of this project successfully demonstrated the ability to make stainless steel from barrier nickel feed. This paved the way for restricted end use products made from stainless steel. Also, after repeated trials and studies, the inducto-slag nickel decontamination process was eliminated as a suitable alternative. Electro-refining appeared to be a promising technology for decontamination of the diffusion plant barrier material. Goals for phase II included conducting experiments to facilitate the development of an electro-refining process to separate technetium from nickel. In parallel with those activities, phase II efforts were to include the development of the necessary processes to make useful products from radioactive scrap metal. Nickel from the diffusion plants as well as stainless steel and carbon steel could be used as feed material for these products

  10. The reuse of scrap and decontamination waste water from decommissioning

    International Nuclear Information System (INIS)

    Deng Junxian; Li Xin; Xie Xiaolong

    2010-01-01

    Huge amount of radioactive scrap with low activity will be generated from reactor decommissioning; the decontamination is concentrated in the surface layer of the scrap. The decontaminated substance can be removed by high pressure water jet to appear the base metal and to reuse the metal. Big amount of radioactive waste water will be generated by this decontamination technology; the radioactive of the waste water is mainly caused by the solid particle from decontamination. To remove the solid particle as clean as possible, the waste water can be reused. Different possible technology to remove the solid particle from the water had been investigated, such as the gravity deposit separation, the filtration and the centrifugal separation etc. The centrifugal separation technology is selected; it includes the hydraulic vortex, the centrifugal filtration and the centrifugal deposit. After the cost benefit analysis at last the centrifugal deposit used butterfly type separator is selected. To reuse the waste water the fresh water consumption and the cost for waste water treatment can be reduced. To reuse the radioactive scrap and the waste water from decommissioning will minimize the radioactive waste. (authors)

  11. Decontamination Technology Development for Nuclear Research Facilities

    International Nuclear Information System (INIS)

    Oh, Won Zin; Jung, Chong Hun; Choi, Wang Kyu; Won, Hui Jun; Kim, Gye Nam

    2004-02-01

    Technology development of surface decontamination in the uranium conversion facility before decommissioning, technology development of component decontamination in the uranium conversion facility after decommissioning, uranium sludge treatment technology development, radioactive waste soil decontamination technology development at the aim of the temporary storage soil of KAERI, Optimum fixation methodology derivation on the soil and uranium waste, and safety assessment methodology development of self disposal of the soil and uranium waste after decontamination have been performed in this study. The unique decontamination technology applicable to the component of the nuclear facility at room temperature was developed. Low concentration chemical decontamination technology which is very powerful so as to decrease the radioactivity of specimen surface under the self disposal level was developed. The component decontamination technology applicable to the nuclear facility after decommissioning by neutral salt electro-polishing was also developed. The volume of the sludge waste could be decreased over 80% by the sludge waste separation method by water. The electrosorption method on selective removal of U(VI) to 1 ppm of unrestricted release level using the uranium-containing lagoon sludge waste was tested and identified. Soil decontamination process and equipment which can reduce the soil volume over 90% were developed. A pilot size of soil decontamination equipment which will be used to development of real scale soil decontamination equipment was designed, fabricated and demonstrated. Optimized fixation methodology on soil and uranium sludge was derived from tests and evaluation of the results. Safety scenario and safety evaluation model were development on soil and uranium sludge aiming at self disposal after decontamination

  12. Decontaminating agents and decontamination processes for nuclear industry and for plant demolition

    International Nuclear Information System (INIS)

    Henning, Klaus; Gojowczyk, Peter

    2012-01-01

    Decontamination of surfaces of materials in nuclear facilities or in nuclear power plants under demolition can be carried out successfully if surface treatment is performed by dipping or in an ultrasonic bath by alternating between alkaline and acid baths with intermediate rinsing in demineralized water. Decontaminating aluminium surfaces sensitive to corrosion requires further treatment in an ultrasonic bath, after the first 2 ultrasonic baths, with a weak alkaline decontaminating agent. This applies alike to components to be decontaminated for re-use and parts of materials to be disposed of. The decontamination action depends on the surfaces either being free from corrosion or else showing pronounced corrosion. (orig.)

  13. TRU decontamination of high-level Purex waste by solvent extraction using a mixed octyl(phenyl)-N,N-diisobutyl-carbamoylmethylphosphine oxide/TBP/NPH (TRUEX) solvent

    International Nuclear Information System (INIS)

    Horwitz, E.P.; Kalina, D.G.; Diamond, H.; Kaplan, L.; Vandegrift, G.F.; Leonard, R.A.; Steindler, M.J.; Schulz, W.W.

    1984-01-01

    The TRUEX (transuranium extraction) process was tested on a simulated high-level dissolved sludge waste (DSW). A batch counter-current extraction mode was used for seven extraction and three scrub stages. One additional extraction stage and two scrub stages and all strip stages were performed by batch extraction. The TRUEX solvent consisted of 0.20 M octyl(phenyl)-N,N-diisobutylcarbamoyl-methylphosphine oxide-1.4 M TBP in Conoco (C 12 -C 14 ). The feed solution was 1.0 M in HNO 3 , 0.3 M in H 2 C 2 O 4 and contained mixed (stable) fission products, U, Np, Pu, and Am, and a number of inert constituents, e.g., Fe and Al. The test showed that the process is capable of reducing the TRU concentration in the DSW by a factor of 4 x 10 4 (to <100 nCi/g of disposed form) and reducing the quantity of TRU waste by two orders of magnitude

  14. Efficacy of liquid and foam decontamination technologies for chemical warfare agents on indoor surfaces.

    Science.gov (United States)

    Love, Adam H; Bailey, Christopher G; Hanna, M Leslie; Hok, Saphon; Vu, Alex K; Reutter, Dennis J; Raber, Ellen

    2011-11-30

    Bench-scale testing was used to evaluate the efficacy of four decontamination formulations on typical indoor surfaces following exposure to the liquid chemical warfare agents sarin (GB), soman (GD), sulfur mustard (HD), and VX. Residual surface contamination on coupons was periodically measured for up to 24h after applying one of four selected decontamination technologies [0.5% bleach solution with trisodium phosphate, Allen Vanguard Surface Decontamination Foam (SDF™), U.S. military Decon Green™, and Modec Inc. and EnviroFoam Technologies Sandia Decontamination Foam (DF-200)]. All decontamination technologies tested, except for the bleach solution, performed well on nonporous and nonpermeable glass and stainless-steel surfaces. However, chemical agent residual contamination typically remained on porous and permeable surfaces, especially for the more persistent agents, HD and VX. Solvent-based Decon Green™ performed better than aqueous-based bleach or foams on polymeric surfaces, possibly because the solvent is able to penetrate the polymer matrix. Bleach and foams out-performed Decon Green for penetrating the highly polar concrete surface. Results suggest that the different characteristics needed for an ideal and universal decontamination technology may be incompatible in a single formulation and a strategy for decontaminating a complex facility will require a range of technologies. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Decontamination of latex gloves; Decontamination de gants en latex

    Energy Technology Data Exchange (ETDEWEB)

    Boutot, P; Schipfer, P; Blachere, A [Commissariat a l' Energie Atomique, Chusclan (France). Centre de Production de Plutonium de Marcoule

    1969-07-01

    Initially the latex gloves used in controlled zones were processed after use as radioactive waste. In view of the continually increasing number used, however, the persons in charge of the SPRAR have considered the possibility of decontaminating the gloves and using them again after control. The recovery installations which have been developed were initially designed rather crudely and operated irregularly; they have been progressively improved as a result of the experience acquired; today they are more really an industrial concern, equipped with automatic machinery. In 1967 it has been possible with this set-up to recover 247000 pairs of gloves, representing nearly 70 per cent of the number treated. (author) [French] Initialement, les gants de latex utilises dans les zones controlees etaient conditionnes apres emploi comme dechets radioactifs. Mais, devant l'augmentation sans cesse croissante des quantites employees, les responsables du SPRAR ont envisage leur decontamination et leur recyclage apres controles. Les installations de recuperation mises au point, de conception artisanale et fonctionnant de maniere episodique au depart, se sont progressivement ameliorees au fur et a mesure de l'experience acquise; elles revetent aujourd'hui le caractere d'une exploitation industrielle equipee de machines automatiques. En 1967, ces nouvelles installations ont permis de recuperer 247000 paires de gants, ce qui represente pres de 70 pour cent des quantites traitees. (auteur)

  16. Radiation decontamination of frozen chicks

    International Nuclear Information System (INIS)

    Khan, M.; Akhtar, T.; Sattar, A.; Khan, I.

    1992-07-01

    In this report decontamination of frozen chicken has been discussed. The pathogenic bacteria present in poultry meats causes food infectious diseases. The spoilage microorganisms in poultry meat quickly render the meat unacceptable due to decomposition of the products resulting in off-odour and development of slime. Irradiation (2-5 kGy) and freezing has been found effective in eliminating various pathogens. These combination treatments were tested in local environment. The results indicated that radiation followed by freezing greatly protected quality of poultry meat during storage for 6 months. (A.B.)

  17. Decontamination and decommissioning: a bibliography

    International Nuclear Information System (INIS)

    McLaren, L.H.

    1982-11-01

    This bibliography contain information on decontamination and decommissioning included in the Department of Energy's Data Base from January 1981 through October 1982. The abstracts are grouped by subject category. Within each category the arrangement is by report number for reports, followed by nonreports in reverse chronological order. These citations are to research reports journal articles, books, patents, theses, and conference papers from worldwide sources. Five indexes, each preceded by a brief description, are provided: corporate author, personal author, subject, contract number, and report umber. (468 abstracts)

  18. Chemical decontamination process and device therefor

    International Nuclear Information System (INIS)

    Takahashi, Ryota; Sakai, Hitoshi

    1998-01-01

    The present invention provides a process and a device for chemical decontamination, which can suppress corrosion of low corrosion resistant materials, keep decontamination properties substantially as same as before and further, reduce the volume of secondary wastes. In a step of reductively melting oxide membranes on an objective material to be decontaminated, a mixture of oxalic acid and a salt thereof is used as a reducing agent, and the reductive melting is conducted while suppressing hydrogen ion concentration of an aqueous liquid system. In order to enhance the reducibility of the oxalic acid ions, it is desirable to add a cyclic hetero compound thereto. The device of the present invention comprises, a decontamination loop including a member to be decontaminated, a heater and a pH meter, a medical injection pump for injecting a reducing agent to the decontamination loop, a metal ion recovering loop including an ion exchange resin tower, a reducing agent decomposing loop including an electrolytic vessel and/or a UV ray irradiation cell, a circulation pump for circulating the decontamination liquid to each of the loops and a plurality of opening/closing valves for switching the loop in which the decontamination liquid is circulated. (T.M.)

  19. Decontamination around the site of Chernobylsk

    International Nuclear Information System (INIS)

    Manesse, D.; Rzepka, J.P.; Maubert, H.

    1990-12-01

    This report describes the decontamination of the site around the nuclear plant of Chernobylsk after the reactor accident of 1986. The work of decontamination in urban areas, buildings, fields and vegetation are detailed. The interventions to reduce the contamination of surface waters and to protect ground waters are also given. (N.C.)

  20. Soil decontamination criteria report, November 1980

    International Nuclear Information System (INIS)

    Riordan, G.A.

    1980-01-01

    A program to access the extent of transuranic soil contamination at DOE sites and to develop methods for their decontamination is underway at Rocky Flats. As part of this program, acceptable soil contamination levels for plutonium proposed by a number of authorities over the past couple of decades were reviewed. From this review, goals for soil decontamination work are proposed. These goals, which relate to the disposition of the products of a decontamination process, are summarized as follows (dpm/g will refer to disintegrations per minute of transuranic nuclides per gram of soil): soil fractions having less than 30 dpm can be disposed of as surface soil with unrestricted usage. Fine soil fractions (less than 100 μm) that have less than 500 dpm and coarse soil fractions that have less than 1000 dpm can be disposed of as subsurface soil as long as usage is controlled to ensure compliance with EPA dosage guidance. Soil concentrates that have an activity greater than the above values but less than 22,000 dpm should be interred in an approved, low level waste burial site. Soil concentrates that are greater than 22,000 dpm should be stored as retrievable waste. Changes in the technical and legal areas of soil decontamination are rapid. Permissible soil decontamination levels will change as will decontamination technology and the ability to monitor the effectiveness of the decontamination processes. As a result, annual updates of decontamination criteria, goals, and monitoring are expected

  1. The 3rd power unit roofing decontamination

    International Nuclear Information System (INIS)

    Samojlenko, Yu.N.; Golubev, V.V.

    1989-01-01

    The most features of the 3rd power unit (PU) roofing decontamination are described: 1) the most active materials were thrown into the 4th PU ruins before the Ukrytie construction completion; 2) the decontamination was fulfilled using remote-controlled mechanisms and manual devices (the main part). 6 figs.; 1 tab

  2. Recent developments in chemical decontamination technology

    Energy Technology Data Exchange (ETDEWEB)

    Wood, C.J. [Electric Power Research Institute, Palo Alto, CA (United States)

    1995-03-01

    Chemical decontamination of parts of reactor coolant systems is a mature technology, used routinely in many BWR plants, but less frequently in PWRs. This paper reviews recent developments in the technology - corrosion minimization, waste processing and full system decontamination, including the fuel. Earlier work was described in an extensive review published in 1990.

  3. PND fuel handling decontamination: facilities and techniques

    International Nuclear Information System (INIS)

    Pan, R.Y.

    1996-01-01

    The use of various decontamination techniques and equipment has become a critical part of Fuel Handling maintenance work at Ontario Hydro's Pickering Nuclear Division. This paper presents an overview of the set up and techniques used for decontamination in the PND Fuel Handling Maintenance Facility and the effectiveness of each. (author). 1 tab., 9 figs

  4. PND fuel handling decontamination: facilities and techniques

    Energy Technology Data Exchange (ETDEWEB)

    Pan, R Y [Ontario Hydro, Toronto, ON (Canada)

    1997-12-31

    The use of various decontamination techniques and equipment has become a critical part of Fuel Handling maintenance work at Ontario Hydro`s Pickering Nuclear Division. This paper presents an overview of the set up and techniques used for decontamination in the PND Fuel Handling Maintenance Facility and the effectiveness of each. (author). 1 tab., 9 figs.

  5. Project gnome decontamination and decommissioning plan

    International Nuclear Information System (INIS)

    1979-04-01

    The document presents the operational plan for conducting the final decontamination and decommissioning work at the site of the first U.S. nuclear detonation designed specifically for peaceful purposes and the first underground event on the Plowshare Program to take place outside the Nevada Test Site. The plan includes decontamination and decommissioning procedures, radiological guidelines, and the NV concept of operations

  6. Chemically reducing decontamination method for radioactive metal

    International Nuclear Information System (INIS)

    Tanaka, Akio; Onuma, Tsutomu; Sato, Hitoshi.

    1994-01-01

    The present invention concerns a decontamination method of electrolytically reducing radioactive metal wastes, then chemically dissolving the surface thereof with a strong acid decontaminating solution. This method utilizes dissolving characteristics of stainless steels in the strong acid solution. That is, in the electrolytic reduction operation, a portion of the metal wastes is brought into contact with a strong acid decontaminating solution, and voltage and current are applied to the portion and keep it for a long period of time so as to make the potential of the immersed portion of the metal wastes to an active soluble region. Then, the electrolytic reduction operation is stopped, and the metal wastes are entirely immersed in the decontaminating solution to decontaminate by chemical dissolution. As the decontaminating solution, strong acid such as sulfuric acid, nitric acid is used. Since DC current power source capacity required for causing reaction in the active soluble region can be decreased, the decontamination facility can be minimized and simplified, and necessary electric power can be saved even upon decontamination of radioactive metal wastes made of stainless steels and having a great area. Further, chemical dissolution can be conducted without adding an expensive oxidizing agent. (N.H.)

  7. Cost effectiveness of dilute chemical decontamination

    International Nuclear Information System (INIS)

    LeSurf, J.E.; Weyman, G.D.

    The basic principles of dilute chemical decontamination are described, as well as the method of application. Methods of computing savings in radiation dose and costs are presented, with results from actual experience and illustrative examples. It is concluded that dilute chemical decontamination is beneficial in many cases. It reduces radiation exposure of workers, saves money, and simplifies maintenance work

  8. Comparison of skin decontamination efficacy of commercial decontamination products following exposure to VX on human skin.

    Science.gov (United States)

    Thors, L; Koch, M; Wigenstam, E; Koch, B; Hägglund, L; Bucht, A

    2017-08-01

    The decontamination efficacy of four commercially available skin decontamination products following exposure to the nerve agent VX was evaluated in vitro utilizing a diffusion cell and dermatomed human skin. The products included were Reactive Skin Decontamination Lotion (RSDL), the Swedish decontamination powder 104 (PS104), the absorbent Fuller's Earth and the aqueous solution alldecontMED. In addition, various decontamination procedures were assessed to further investigate important mechanisms involved in the specific products, e.g. decontamination removal from skin, physical removal by sponge swabbing and activation of degradation mechanisms. The efficacy of each decontamination product was evaluated 5 or 30 min after dermal application of VX (neat or diluted to 20% in water). The RSDL-lotion was superior in reducing the penetration of VX through human skin, both when exposed as neat agent and when diluted to 20% in water. Swabbing with the RSDL-sponge during 2 min revealed decreased efficacy compared to applying the RSDL-lotion directly on the skin for 30 min. Decontamination with Fuller's Earth and alldecontMED significantly reduced the penetration of neat concentration of VX through human skin. PS104-powder was insufficient for decontamination of VX at both time-points, independently of the skin contact time of PS104. The PS104-slurry (a mixture of PS104-powder and water), slightly improved the decontamination efficacy. Comparing the time-points for initiated decontamination revealed less penetrated VX for RSDL and Fuller's Earth when decontamination was initiated after 5 min compared to 30 min post-exposure, while alldecontMED displayed similar efficacy at both time-points. Decontamination by washing with water only resulted in a significant reduction of penetrated VX when washing was performed 5 min after exposure, but not when decontamination was delayed to 30 min post-exposure of neat VX. In conclusion, early initiated decontamination with the

  9. NRC regulations and positions concerning decontamination

    International Nuclear Information System (INIS)

    McCracken, C.

    1982-09-01

    The U.S. Nuclear Regulatory Commission encourages the use of decontamination to reduce man-rem exposure. The Commission feels that there are several processes developed to the point where soft decontamination can be applied to an entire plant in the near future. A utility can do a decontamination under its own licence without coming in for regulatory review if the process does not involve a change in technical specifications for the plant or does not involve unreviewed safety questions. Prior verbal notification is required for some steam generator secondary side cleaning or for decontamination of individual components that have not been removed from the reactor using chemicals not normally added to the reactor coolant. Prior written notification is required for steam generator secondary side crevice cleaning or sludge removal at a dented unit, or for chemical decontamination of reactor coolant systems or safety-related systems using chemicals not normally added to the coolant

  10. Technical Improvements to an Absorbing Supergel for Radiological Decontamination in Tropical Environments

    Energy Technology Data Exchange (ETDEWEB)

    Kaminski, Michael D. [Argonne National Lab. (ANL), Argonne, IL (United States); Mertz, Carol J. [Argonne National Lab. (ANL), Argonne, IL (United States); Kivenas, Nadia [Argonne National Lab. (ANL), Argonne, IL (United States); demmer, Rick [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-01-01

    Argonne National Laboratory (Argonne) developed a superabsorbing gel-based process (SuperGel) for the decontamination of cesium from concrete and other porous building materials. Here, we report on results that tested the gel decontamination technology on specific concrete and ceramic formulations from a coastal city in Southeast Asia, which may differ significantly from some U.S. sources. Results are given for the evaluation of americium and cesium sequestering agents that are commercially available at a reasonable cost; the evaluation of a new SuperGel formulation that combines the decontamination properties of cesium and americium; the variation of the contamination concentration to determine the effects on the decontamination factors with concrete, tile, and brick samples; and pilot-scale testing (0.02–0.09 m2 or 6–12 in. square coupons).

  11. Decontamination of radioactive clothing using microemulsion in carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Jaeryong; Jang, Jina; Park, Kwangheon; Kim, Hongdoo; Kim, Hakwon [Kyunghee Univ., Seoul (Korea, Republic of); Yim, Sanghak; Yoon, Weonseob [Ulchin Nuclear Power Site, Ulchin (Korea, Republic of)

    2006-07-01

    Nuclear power is intrinsically a clean energy source due to its high energy density and low generation of waste. However, as the nuclear industry grows, a variety of radioactive wastes are increased gradually. Major subjects include contaminated components, tools, equipment, containers and facilities as well as nuclear waste such as uranium scrap and radioactive clothing. The radioactive waste can be classified by its creation. There are Trans-Uranium Nuclides (TRU), Fission Products (FP) and corrosion products. Nuclear decontamination has become an important issue in the nuclear industry. The conventional methods have some problems such as the production of secondary wastes and the use of toxic solvents. We need to develop a new method of decontamination and suggest a use of microemulsion in carbon dioxide to overcome these disadvantages. The microemulsion is the clear solution that contains the water, surfactant and carbon dioxide. The surfactant surrounded the droplet into carbon dioxide and this state is thermodynamically stable. That is, the microemulsion has a structure similar to that of a conventional water-based surfactant system. Generally, the size of droplet is about 5 {approx} 10nm. The microemulsion is able to decontaminate radioactive waste so that the polar substance is removed by water and the non-polar substance is removed by carbon dioxide. After the decontamination process, the microemulsion is separated easily to surfactant and water by decreasing the pressure under the cloud point. This way, only radioactive wastes are left in the system. Cleaned carbon dioxide is then collected and reused. Thus, there are no secondary wastes. Carbon dioxide is considered an alternative process medium. This is because it is non-toxic, non-flammable, inexpensive and easy to handle. Additionally, the tunable properties of carbon dioxide through pressure and temperature control are versatile for use in extracting organic materials. In this paper, we examine the

  12. Development of the dry decontamination technique using plasma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Soo; Seo, Yong Dae; Lee, Dong Uk; Jeon, Sang Hwan; Jung, Young Suk [Hanyang University, Seoul (Korea)

    2001-04-01

    In order to develop an advanced dry decontamination method, dry decontamination technique using gaseous plasma is studied. Scopes of the research are 1) literature survey and case studies of the international R and D activities and industrial application, 2) contaminant characteristics analysis, 3) feasibility and applicability study of the unit techniques, 4) process development study on the plasma decontamination, 5) plasma diagnostics and quantitative analysis by QMS and OES, and 6) design of (microwave) plasma torch system. The major research results are as belows. The maximum etching rate of UO{sub 2} is achieved to be 0.8 {mu}m/min. under 300 deg C, 150 W CF{sub 4}/O{sub 2}/N{sub 2} r.f. plasma maintaining the optimum ratio of CF{sub 4}/O{sub 2} of four, and that of Co and Mo is 0.06 {mu}m/min. and 1.9 {mu}m/min., respectively, under 380 deg C, 220 W CF{sub 4}/O{sub 2} r.f. plasma. The optimum process for the dry decontamination of TRU, CP, and or FP nuclides, therefore, requires the optimum gas composition above 350 deg C and 220W power. It is also demonstrated that this optimum process can be extrapolated to atmospheric high power torch system. In conclusion, if plasma power and temperature increases with maintaining the optimum gas composition, this dry decontamination techniques must be definitely effective and efficient. 17 refs., 62 figs., 4 tabs. (Author)

  13. Fighting Ebola through Novel Spore Decontamination Technologies for the Military

    Directory of Open Access Journals (Sweden)

    Christopher J. Doona

    2015-08-01

    Full Text Available AbstractRecently, global public health organizations such as Doctors without Borders (MSF, the World Health Organization (WHO, Public Health Canada, National Institutes of Health (NIH, and the U.S. government developed and deployed Field Decontamination Kits (FDKs, a novel, lightweight, compact, reusable decontamination technology to sterilize Ebola-contaminated medical devices at remote clinical sites lacking infra-structure in crisis-stricken regions of West Africa (medical waste materials are placed in bags and burned. The basis for effectuating sterilization with FDKs is chlorine dioxide (ClO2 produced from a patented invention developed by researchers at the US Army – Natick Soldier RD&E Center (NSRDEC and commercialized as a dry mixed-chemical for bacterial spore decontamination. In fact, the NSRDEC research scientists developed an ensemble of ClO2 technologies designed for different applications in decontaminating fresh produce; food contact and handling surfaces; personal protective equipment; textiles used in clothing, uniforms, tents, and shelters; graywater recycling; airplanes; surgical instruments; and hard surfaces in latrines, laundries, and deployable medical facilities. These examples demonstrate the far-reaching impact, adaptability, and versatility of these innovative technologies. We present herein the unique attributes of NSRDEC’s novel decontamination technologies and a Case Study of the development of FDKs that were deployed in West Africa by international public health organizations to sterilize Ebola-contaminated medical equipment. FDKs use bacterial spores as indicators of sterility. We review the properties and structures of spores and the mechanisms of bacterial spore inactivation by ClO2. We also review mechanisms of bacterial spore inactivation by novel, emerging, and established nonthermal technologies for food preservation, such as high pressure processing, irradiation, cold plasma, and chemical sanitizers

  14. Decontamination of radioactive clothing using microemulsion in carbon dioxide

    International Nuclear Information System (INIS)

    Yoo, Jaeryong; Jang, Jina; Park, Kwangheon; Kim, Hongdoo; Kim, Hakwon; Yim, Sanghak; Yoon, Weonseob

    2006-01-01

    Nuclear power is intrinsically a clean energy source due to its high energy density and low generation of waste. However, as the nuclear industry grows, a variety of radioactive wastes are increased gradually. Major subjects include contaminated components, tools, equipment, containers and facilities as well as nuclear waste such as uranium scrap and radioactive clothing. The radioactive waste can be classified by its creation. There are Trans-Uranium Nuclides (TRU), Fission Products (FP) and corrosion products. Nuclear decontamination has become an important issue in the nuclear industry. The conventional methods have some problems such as the production of secondary wastes and the use of toxic solvents. We need to develop a new method of decontamination and suggest a use of microemulsion in carbon dioxide to overcome these disadvantages. The microemulsion is the clear solution that contains the water, surfactant and carbon dioxide. The surfactant surrounded the droplet into carbon dioxide and this state is thermodynamically stable. That is, the microemulsion has a structure similar to that of a conventional water-based surfactant system. Generally, the size of droplet is about 5 ∼ 10nm. The microemulsion is able to decontaminate radioactive waste so that the polar substance is removed by water and the non-polar substance is removed by carbon dioxide. After the decontamination process, the microemulsion is separated easily to surfactant and water by decreasing the pressure under the cloud point. This way, only radioactive wastes are left in the system. Cleaned carbon dioxide is then collected and reused. Thus, there are no secondary wastes. Carbon dioxide is considered an alternative process medium. This is because it is non-toxic, non-flammable, inexpensive and easy to handle. Additionally, the tunable properties of carbon dioxide through pressure and temperature control are versatile for use in extracting organic materials. In this paper, we examine the

  15. Decontamination Experiments on Intact Pig Skin Contaminated with Beta-Gamma- Emitting Nuclides

    Energy Technology Data Exchange (ETDEWEB)

    Edvardsson, K A; Hagsgaard, S [AB Atomenergi, Nykoeping (Sweden); Swensson, A [Dept. of Occupational Medicine, Karolinska Sjukhuset, Stockholm (Sweden)

    1966-11-15

    A number of decontamination experiments have been performed on intact pig skin. In most of the experiments NaI-131 in water solution has been utilized because this nuclide is widely used within the Studsvik research establishment, is easy to detect and relatively harmless, and is practical to use in these experiments. Among the {beta} {gamma}-nuclides studied 1-131 has furthermore proved to be the one most difficult to remove from the skin. The following conclusions and recommendations regarding the decontamination of skin are therefore valid primarily for iodine in the form of Nal, but are probably also applicable to many other {beta} {gamma}-nuclides. a) A prolonged interval between contamination and decontamination has a negative effect on the result of the decontamination. Therefore start decontamination as soon as possible after the contamination. b) Soap and water has proved to be the most suitable decontamination agent. A number of other agents have appeared to be harmful to the skin. Therefore, first of all use only soap and water in connection with gentle rubbing. c) No clear connection between the temperature of the water for washing and the result of the decontamination has been demonstrated. d) Skin not degreased before the contamination seems to be somewhat easier to decontaminate than degreased skin, particularly if the activity has been on the skin for a long time. Therefore do not remove the sebum of the skin when engaged on radioactive work involving contamination risks. e) Irrigation of the contaminated surface with a solution containing the corresponding inactive ions or ordinary water in large quantities may considerably decrease the skin contamination. f) In radioactive work of long duration involving high risks of contamination prophylactic measures in the form of a protective substance ('invisible glove'), type Kerodex, may make decontamination easier.

  16. Decontamination Experiments on Intact Pig Skin Contaminated with Beta-Gamma- Emitting Nuclides

    International Nuclear Information System (INIS)

    Edvardsson, K.A.; Hagsgaard, S.; Swensson, A.

    1966-11-01

    A number of decontamination experiments have been performed on intact pig skin. In most of the experiments NaI-131 in water solution has been utilized because this nuclide is widely used within the Studsvik research establishment, is easy to detect and relatively harmless, and is practical to use in these experiments. Among the β γ-nuclides studied 1-131 has furthermore proved to be the one most difficult to remove from the skin. The following conclusions and recommendations regarding the decontamination of skin are therefore valid primarily for iodine in the form of Nal, but are probably also applicable to many other β γ-nuclides. a) A prolonged interval between contamination and decontamination has a negative effect on the result of the decontamination. Therefore start decontamination as soon as possible after the contamination. b) Soap and water has proved to be the most suitable decontamination agent. A number of other agents have appeared to be harmful to the skin. Therefore, first of all use only soap and water in connection with gentle rubbing. c) No clear connection between the temperature of the water for washing and the result of the decontamination has been demonstrated. d) Skin not degreased before the contamination seems to be somewhat easier to decontaminate than degreased skin, particularly if the activity has been on the skin for a long time. Therefore do not remove the sebum of the skin when engaged on radioactive work involving contamination risks. e) Irrigation of the contaminated surface with a solution containing the corresponding inactive ions or ordinary water in large quantities may considerably decrease the skin contamination. f) In radioactive work of long duration involving high risks of contamination prophylactic measures in the form of a protective substance ('invisible glove'), type Kerodex, may make decontamination easier

  17. Nuclear engineering questions: power, reprocessing, waste, decontamination, fusion

    International Nuclear Information System (INIS)

    Walton, R.D. Jr.

    1979-01-01

    This volume contains papers presented at the chemical engineering symposium on nuclear questions. Specific questions addressed by the speakers included: nuclear power - why and how; commercial reprocessing - permanent death or resurrection; long-term management of commercial high-level wastes; long-term management of defense high-level waste; decontamination and decommissioning of nuclear facilities, engineering aspects of laser fusion I; and engineering aspects of laser fusion II. Individual papers have been input to the Energy Data Base previously

  18. Psychosocial considerations for mass decontamination

    International Nuclear Information System (INIS)

    Lemyre, L.; Johnson, C.; Corneil, W.

    2010-01-01

    Mass exposure to explosions, infectious agents, food-borne illnesses, chemicals or radiological materials may require mass decontamination that have critical psychosocial implications for the public and for both traditional and non-traditional responders in terms of impact and of response. Five main issues are common to mass decontamination events: (i) perception, (ii) somatisation, (iii) media role and communication, (iv) information sharing, (v) behavioural guidance and (vi) organisational issues. Empirical evidence is drawn from a number of cases, including Chernobyl; Goiania, Brazil; the sarin gas attack in Tokyo; the anthrax attacks in the USA; Three Mile Island; and by features of the 2003 severe acute respiratory syndrome pandemic. In this paper, a common platform for mass casualty management is explored and suggestions for mass interventions are proposed across the complete event timeline, from pre-event threat and warning stages through to the impact and reconstruction phases. Implication for responders, health care and emergency infrastructure, public behaviour, screening processes, risk communication and media management are described. (authors)

  19. Decontamination liquid waste processing method

    International Nuclear Information System (INIS)

    Enda, Masami; Hosaka, Katsumi.

    1992-01-01

    Liquid wastes after electrolytic reduction are caused to flow through an anionic exchange membrane in a diffusion dialysis step, and liquid wastes and dialyzed water are passed in a countercurrent manner. Since acids in the liquid wastes transfer on the side of the dialyzed water due to the difference of concentration between the liquid wastes and the dialyzed water, acids can be easily recovered from the liquid wastes. If the acid-removed liquid wastes are put to electrodeposition in an electrodepositing step, the electrodepositing reactions between radioactive materials such as Co ion, Mn ion and leached metals such as Fe ions and Cr ions are caused preferentially to hydrogen generation reaction on a metal deposition cathode. Accordingly, metal ions can be easily separated from the liquid wastes. Since the separated liquid wastes are an aqueous solution in which cerium ions as a decontaminant and an acid at low concentration are dissolved, the concentration thereof is controlled by mixing them to acid recovering water after the diffusion dialysis and they can be reused as the decontaminant. (T.M.)

  20. Surface decontamination of Type 304L stainless steel with electrolytically generated hydrogen: Design and operation of the electrolyzer

    International Nuclear Information System (INIS)

    Bellanger, G.

    1993-01-01

    The surface of tritiated Type 304L stainless steel is decontaminated by isotopic exchange with the hydrogen generated in an electrolyzer. This steel had previously been exposed to tritium in a tritium gas facility for several years. The electrolyzer for the decontamination uses a conducting solid polymer electrolyte made of a Nafion membrane. The cathode where the hydrogen is formed is nickel deposited on one of the polymer surfaces. This cathode is placed next to the region of the steel to be decontaminated. The decontamination involves, essentially, the tritiated oxide layers of which the initial radioactivity is ∼ 5 kBq/cm 2 . After treatment for 1 h, the decontamination factor is 8. 9 refs., 16 figs., 2 tabs

  1. Studies of radioactive deposition on farm buildings and testing of some methods for decontamination

    International Nuclear Information System (INIS)

    Andersson, Inger; Erlandsson, B.; Hansson, J.; Dolby, C.M.

    1993-01-01

    Studies were made of radioactive fallout on roofs of farm buildings and of some methods of decontamination. The aim was to find ways of reducing the external radiation dose to farmers working and farm animals housed in stables in a fallout situation. The roof material studied was steel plate (A) and tile (B,C, D), each with four sample areas of ca. 1 m 2 . The roof samples were collected at three places and from totally four building in regions which in 1986 (after the Chernobyl fallout) has a 137 Cs ground depositions of 3040 kBq/m 2 (A, B, C) and > 100 kBq/m 2 (D). Four different decontamination methods were tested: 1. High pressure washing with water. 2. Repeated high pressure washing with water. 3. Application of foam of a sanitizing chemical for livestock buildings followed by high pressure washing with water. 4. Application of a solution of KCl followed by high pressure washing with water. In C, the effect of decontamination expressed as the percentage decrease of the 137 Cs activity was on average for all methods, 55%. This material was coated before the decontamination by a marked growth of algae or moss, which was effectively washed off during the sanitizing procedure. In B, the average activity decontamination effect was 25%, while in D (with the highest original activity, but without growth of organic material) the effect was very small, 3%. In A, the activity level before decontamination was so low that measurements after decontamination were considered unnecessary. Method number 4 was the most effective in B and C, 32% and 64%, respectively, while method number 3 was the most effective in D, 5.7%. The results indicate that good effects can be achieved in radioactivity decontamination of roof material with equipment and chemicals which are normally available on farms

  2. Laser Decontamination of Type 304 Stainless Steel Contaminated with Co2+ and CeO2

    International Nuclear Information System (INIS)

    Won, Hui Jun; Baigalmaa, Byambatseren; Moon, Jei Kwon; Jung, Chong Hun; Lee, Kune Woo

    2009-01-01

    The merits of laser decontamination are a remote operation, a short application time, and the high removal efficiency. And also, generation of the secondary waste is negligible. A series of laser decontamination test by Qswitched Nd:YAG laser at 532 nm were performed on stainless steel specimens artificially contaminated with the Co 2+ and CeO 2 , respectively. Test results were examined by SEM and EPMA

  3. Phase 2 microwave concrete decontamination results

    International Nuclear Information System (INIS)

    White, T.L.; Foster, D. Jr.; Wilson, C.T.; Schaich, C.R.

    1995-01-01

    The authors report on the results of the second phase of a four-phase program at Oak Ridge National Laboratory to develop a system to decontaminate concrete using microwave energy. The microwave energy is directed at the concrete surface through the use of an optimized wave guide antenna, or applicator, and this energy rapidly heats the free water present in the interstitial spaces of the concrete matrix. The resulting steam pressure causes the surface to burst in much the same way popcorn pops in a home microwave oven. Each steam explosion removes several square centimeters of concrete surface that are collected by a highly integrated wave guide and vacuum system. The authors call this process the microwave concrete decontamination, or MCD, process. In the first phase of the program the principle of microwaves concrete removal concrete surfaces was demonstrated. In these experiments, concrete slabs were placed on a translator and moved beneath a stationary microwave system. The second phase demonstrated the ability to mobilize the technology to remove the surfaces from concrete floors. Area and volume concrete removal rates of 10.4 cm 2 /s and 4.9 cm 3 /S, respectively, at 18 GHz were demonstrated. These rates are more than double those obtained in Phase 1 of the program. Deeper contamination can be removed by using a longer residence time under the applicator to create multiple explosions in the same area or by taking multiple passes over previously removed areas. Both techniques have been successfully demonstrated. Small test sections of painted and oil-soaked concrete have also been removed in a single pass. Concrete with embedded metal anchors on the surface has also been removed, although with some increased variability of removal depth. Microwave leakage should not pose any operational hazard to personnel, since the observed leakage was much less than the regulatory standard

  4. Microbial decontamination of uranium mine drainage

    International Nuclear Information System (INIS)

    Hard, B.C.; Babel, W.

    2001-01-01

    One of the problems one is faced with when uranium mines are closed is the decontamination of acid mine drainage (AMD) from tailings and flooding of the underground mines. The high concentrations of sulfates and metals in mining water make it impossible to dispose of the water into rivers without having to decontaminate it first. A bioremediation process is proposed in which sulfate-reducing bacteria are used to remove metals, neutralize the water and reduce the sulfate concentrations. Methylotrophic sulfate-reducing strains have been isolated which can be used in such a process. Lab scale experiments with different reactor types were carried out in order to find the optimum design for this bioremediation process. Comparisons were made between methanol and other electron donors with regards to their suitability as substrate for this process. Methanol was found to be most suited. Laboratory data suggest that immobilizing the bacteria on pumice particles increases the sulfate-reduction rate (SRR) up to three fold to 18 mg/l.h, compared to the rates of free flowing cells of between 3.7 and 6.8 mg/l.h. Preliminary experiments on a larger scale (15 l) using acid mine drainage pH 2.5 show SRR of 0.71 mg/l.h. In biosorption experiments up to 140 mg of aluminium per g biomass was removed from the water. One strain was found to reduce uranium VI, thus changing it from the soluble to the insoluble form. The application of the proposed process with regards to bioremediation of AMD are discussed. (orig.)

  5. The ultrasonic copper and brass decontamination study; Etude de la decontamination du cuivre et des laitons en presence d'ultra-sons

    Energy Technology Data Exchange (ETDEWEB)

    Courtault, J; Kerdelleau, J de; Mestre, E [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    The use of ultra-sounds as a decontamination technic does not bring an absolute solution. As a function of the materials it seemed necessary to find what was the optimum conditions for using the ultra-sounds and to define not only the ultra-sonic factors but also the chemical solutions which bring some appreciable decontamination factors without bringing any too important corrosion processus. This report gives the results of this study applied to copper and brass. This study allowed to select some effective treatment baths on the two types of contamination: plutonium and fission products. (authors) [French] L'emploi des ultra-sons comme technique de decontamination n'amene pas une solution absolue. Il est apparu necessaire de rechercher en fonction de la nature du materiau a decontaminer quelles etaient les conditions optimales d'utilisation des ultra-sons et de definir alors non seulement les facteurs ultrasoniques mais encore les solutions chimiques qui apportent des facteurs de decontamination appreciables sans amener des phenomenes de corrosion trop importants. Ce rapport donne les resultats de cette etude appliquee au cuivre et aux laitons. Cette etude a permis de selectionner des bains de traitement efficaces dans les deux cas de contamination: plutonium et produits de fission. (auteurs)

  6. Development of the Decontamination and Decommissioning Technology for Nuclear Facilities

    International Nuclear Information System (INIS)

    Lee, K. W.; Moon, J. K.; Won, C. H.

    2010-04-01

    The research results could be used for a design of a remote ablation decontamination system and ultimately applicable for an decontamination of high radiation facilities such as the DUPIC and PIEF. The evaluation technology of decommissioning process must be developed and will be used for the ALARA planning tool of decommissioning process and demonstrated for tools of decommissioning equipment. Also, this technology can be used for tools workplaces with high work difficulty such as large-scale chemical plant, under water and space. It is expected that the technology for a volume reduction and self-disposal of dismantled concrete wastes can be contributed to the establishment of a management plan for radioactive dismantled concrete wastes through the minimization of final waste volume

  7. Decontamination of an Analytical Laboratory Hot Cell Facility

    International Nuclear Information System (INIS)

    Michelbacher, J.A.; Henslee, S.P.; Rosenberg, K.E.; Coleman, R.M.

    1995-11-01

    An Analytical Laboratory Hot Cell Facility at Argonne National Laboratory-West (ANL-W) had been in service for nearly thirty years. In order to comply with current DOE regulations governing such facilities and meet programmatic requirements, a major refurbishment effort was mandated. Due to the high levels of radiation and contamination within the cells, a decontamination effort was necessary to provide an environment that permitted workers to enter the cells to perform refurbishment activities without receiving high doses of radiation and to minimize the potential for the spread of contamination. State-of-the-art decontamination methods, as well as time-proven methods were utilized to minimize personnel exposure as well as maximize results

  8. Decontamination of Savannah River Plant waste glass canisters

    International Nuclear Information System (INIS)

    Rankin, W.N.

    1982-01-01

    A Defense Waste Processing Facility (DWPF) is currently being designed to convert Savannah River Plant (SRP) liquid, high-level radioactive waste into a solid form, such as borosilicate glass. The outside of the canisters of waste glass must have very low levels of smearable radioactive contamination before they are removed from the DWPF to prevent the spread of radioactivity. Several techniques were considered for canister decontamination: high-pressure water spray, electropolishing, chemical dissolution, and abrasive blasting. An abrasive blasting technique using a glass frit slurry has been selected for use in the DWPF. No additional equipment is needed to process waste generated from decontamination. Frit used as the abrasive will be mixed with the waste and fed to the glass melter. In contrast, chemical and electrochemical techniques require more space in the DWPF, and produce large amounts of contaminated byproducts which are difficult to immobilize by vitrification

  9. Analytical cell decontamination and shielding window refurbishment. Final report, March 1984-March 1985

    International Nuclear Information System (INIS)

    Smokowski, R.T.

    1985-01-01

    This is a report on the decontamination and refurbishment of five inactive contaminated analytical cells and six zinc bromide filled shielding windows. The analytical cells became contaminated during the nuclear fuel reprocessing carried out by Nuclear Fuel Services from 1966 to 1972. The decontamination and decommissioning (D and D) work was performed in these cells to make them useful as laboratories in support of the West Valley Demonstration Project. To accomplish this objective, unnecessary equipment was removed from these cells. Necessary equipment and the interior of each cell were decontaminated and repaired. The shielding windows, essentially tanks holding zinc bromide, were drained and disassembled. The deteriorated, opaque zinc bromide was refined to optical clarity and returned to the tanks. All wastes generated in this operation were characterized and disposed of properly. All the decontamination and refurbishment was accomplished within 13 months. The Analytical Hot Cell has been turned over to Analytical Chemistry for the performance high-level waste (HLW) characterization analysis

  10. A study on decontamination and decommissioning of experimental DUPIC equipment at PIEF 9405 hot cell

    International Nuclear Information System (INIS)

    Lee, H. H.; Park, J. J.; Shin, J. M.; Yang, M. S.; Lee, H. S.; Lee, E. P.

    2000-09-01

    The characterization experiment for powder and sintered fuel had been performed using about 1 kg-U spent PWR fuel at No. 9405 hot-cell in PIEF(Post Irradiated Experiment Facility) since early in 1999. Currently, The experiments in PIEF have been completed. It is supposed to dismantle and decontaminate the installed equipment by the end of year 2000. Since all of DUPIC equipment in hot-cell are contaminated by high radioactive material, the decontamination and dismantlement must br performed remotely by M/S manipulator. During the radioactive waste packing and transportation, the reduction method of radiation exposure has to be considered. Firstly, This report describes the basic plan for dismantlement/decontamination of the characterization equipment(power and sintered fuel). And methods of measurement/packing/ transportation, method of dismantlement/decontamination of the experimental apparatus and the reduction method of radiation dose exposure, etc. are explained in order

  11. Low corrosive chemical decontamination method using pH control. 1. Basic system

    International Nuclear Information System (INIS)

    Nagase, Makoto; Ishida, Kazushige; Uetake, Naohito; Anazawa, Kazumi; Nakamura, Fumito; Yoshikawa, Hiroo; Tamagawa, Tadashi; Furukawa, Kiyoharu

    2001-01-01

    A new low corrosive decontamination method was developed which uses both oxalic acid and hydrazine as the reducing agent and potassium permanganate as the oxidizing agent. Less corrosion of structural materials during the decontamination is realized by pH control of the reducing agent. The pH of 2.5, attained by adding hydrazine to oxalic acid, was the optimum pH for maintaining a high decontamination effect and lowering the corrosion at the same time. As this reducing agent can be decomposed into carbon dioxide, nitrogen and water by using a catalyst column with hydrogen peroxide, the amount of secondary radioactive waste is small. These good features were demonstrated through actual plant decontamination tasks. (author)

  12. Current and emerging strategies for organophosphate decontamination: special focus on hyperstable enzymes.

    Science.gov (United States)

    Jacquet, Pauline; Daudé, David; Bzdrenga, Janek; Masson, Patrick; Elias, Mikael; Chabrière, Eric

    2016-05-01

    Organophosphorus chemicals are highly toxic molecules mainly used as pesticides. Some of them are banned warfare nerve agents. These compounds are covalent inhibitors of acetylcholinesterase, a key enzyme in central and peripheral nervous systems. Numerous approaches, including chemical, physical, and biological decontamination, have been considered for developing decontamination methods against organophosphates (OPs). This work is an overview of both validated and emerging strategies for the protection against OP pollution with special attention to the use of decontaminating enzymes. Considerable efforts have been dedicated during the past decades to the development of efficient OP degrading biocatalysts. Among these, the promising biocatalyst SsoPox isolated from the archaeon Sulfolobus solfataricus is emphasized in the light of recently published results. This hyperthermostable enzyme appears to be particularly attractive for external decontamination purposes with regard to both its catalytic and stability properties.

  13. Decontamination of large horizontal concrete surfaces outdoors

    International Nuclear Information System (INIS)

    Barbier, M.M.; Chester, C.V.

    1980-01-01

    A study is being conducted of the resources and planning that would be required to clean up an extensive contamination of the outdoor environment. As part of this study, an assessment of the fleet of machines needed for decontaminating large outdoor surfaces of horizontal concrete will be attempted. The operations required are described. The performance of applicable existing equipment is analyzed in terms of area cleaned per unit time, and the comprehensive cost of decontamination per unit area is derived. Shielded equipment for measuring directional radiation and continuously monitoring decontamination work are described. Shielding of drivers' cabs and remote control vehicles is addressed

  14. Deactivation, Decontamination and Decommissioning Project Summaries

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, David Shane; Webber, Frank Laverne

    2001-07-01

    This report is a compilation of summary descriptions of Deactivation, Decontamination and Decommissioning, and Surveillance and Maintenance projects planned for inactive facilities and sites at the INEEL from FY-2002 through FY-2010. Deactivations of contaminated facilities will produce safe and stable facilities requiring minimal surveillance and maintenance pending further decontamination and decommissioning. Decontamination and decommissioning actions remove contaminated facilities, thus eliminating long-term surveillance and maintenance. The projects are prioritized based on risk to DOE-ID, the public, and the environment, and the reduction of DOE-ID mortgage costs and liability at the INEEL.

  15. Guide for decontaminating swimming pool at schools

    International Nuclear Information System (INIS)

    Matsuhashi, Shimpei; Kurikami, Hiroshi; Yasuda, Ryo; Takano, Takao; Seko, Noriaki; Naganawa, Hirochika; Kuroki, Ryota; Saegusa, Jun

    2012-07-01

    Because of TEPCO Fukushima Dai-ichi Nuclear Power Plant accident due to the Great East Japan Earthquake, a huge amount of radioactive materials was widely dispersed and precipitated into the environment. Swimming pools in Fukushima prefectures were contaminated with the radioactives. We JAEA carried out several demonstration tests to decontaminate the radioactives and discharge the pool water safely. We concluded the results obtained from the tests as 'Guide for decontaminating Swimming Pool at School' and released it quickly. Following this, we also released the guide in English. This manuscript, as an experimental report of the swimming pool water decontamination, is consisted from the guide in Japanese and English prepared. (author)

  16. Mechanical and chemical decontamination of surfaces

    International Nuclear Information System (INIS)

    Kienhoefer, M.

    1982-01-01

    Decontamination does not mean more than a special technique of cleaning surfaces by methods well known in the industry. The main difference consists in the facts that more than just the visible dirt is to be removed and that radioactive contamination cannot be seen. Especially, intensive mechanical and chemical carry-off methods are applied to attack the surfaces. In order to minimize damages caused to the surfaces, the decontamination method is to adapt to the material and the required degree of decontamination. The various methods, their advantages and disadvantages are described, and the best known chemical solutions are shown. (orig./RW)

  17. Guide for decontaminating swimming pool at schools

    Energy Technology Data Exchange (ETDEWEB)

    Matsuhashi, Shimpei; Kurikami, Hiroshi; Yasuda, Ryo; Takano, Takao; Seko, Noriaki; Naganawa, Hirochika; Kuroki, Ryota; Saegusa, Jun

    2012-07-15

    Because of TEPCO Fukushima Dai-ichi Nuclear Power Plant accident due to the Great East Japan Earthquake, a huge amount of radioactive materials was widely dispersed and precipitated into the environment. Swimming pools in Fukushima prefectures were contaminated with the radioactives. We JAEA carried out several demonstration tests to decontaminate the radioactives and discharge the pool water safely. We concluded the results obtained from the tests as 'Guide for decontaminating Swimming Pool at School' and released it quickly. Following this, we also released the guide in English. This manuscript, as an experimental report of the swimming pool water decontamination, is consisted from the guide in Japanese and English prepared. (author)

  18. Performance test of wet type decontamination device

    International Nuclear Information System (INIS)

    Lee, E. P.; Kim, E. G.; Min, D. K.; Jun, Y. B.; Lee, H. K.; Seu, H. S.; Kwon, H. M.; Hong, K.P.

    2003-01-01

    The intervention area located at rear hot cell can be contaminated by hot cell maintenance work. For effective decontamination of the intervention floor a wet type decontamination device was developed. The device was assembled with a brush rotating part, a washing liquid supplying part, an intake part for recovering contaminated liquid and a device moving cart part. The device was made of stainless steel for easy decontamination and corrosion resistance. The function test carried out at intervention area of the PIE facility showed good performance

  19. Decontamination of CANDU primary coolant system

    International Nuclear Information System (INIS)

    Pettit, P.J.

    1975-01-01

    Decontamination of radioactive systems is necessary to reduce personnel radiation exposures and also to reduce exposure during special work. Mechanical decontamination methods are sometimes useful, but most contaminated surfaces are inaccessible, so chemical decontamination often is preferred. The A-P Citrox method will remove most contaminants from CANDU systems, but is costly and long, damages components, and produces large quantities of radioactive liquid waste. The Redox cycling process is fast and inexpensive, produces only solid wastes, but removes small quantities of deposit from Monel only. The CAN-DECON process removes deposits from most materials including fuel cladding and has many other advantages. (author)

  20. Method of decontaminating primary coolant circuits

    International Nuclear Information System (INIS)

    Ishibashi, Masaru; Sumi, Masao.

    1981-01-01

    Purpose: To eliminate hard contaminated layers as well as soft contaminated layers without injuring substrate materials, upon decontamination of radiation contaminated portions in equipments and pipeways constituting primary coolant circuits. Constitution: High pressure water from a high pressure pump is jetted out from the nozzle of a spray gun to the radiation contaminated portions in equipments, for example, to the surface of water chamber in a vapor evaporator. High pressure pure water or aqueous boric acid is jetted out from the periphery and boric oxide particles (of about 1 - 100 μ particle size) are jetted out from the center of the nozzle of the spray gun. The particles (blasting material) jetted out together with the high pressure water impinge on the contaminated surfaces to remove the contaminated layers. Upon impingement, the high pressure water acts as the shock absorber for the blasting material and, after the impingement, it flows down to the bottom of the water chamber, and the blasting material is dissolved in the high pressure water. (Horiuchi, T.)

  1. A study of the decontamination effect of commercial detergents on the skin

    International Nuclear Information System (INIS)

    Takasaki, Koji; Miyabe, Kenjiro

    2003-01-01

    Titanium dioxide paste is generally used as the radiological skin decontaminant in the radiation control area at Japan Nuclear Cycle Development Institute (JNC) Tokai works. It is a typical and proven skin decontaminant in the nuclear industry, but there is a disadvantage in that it has a short shelf life. Recently, many detergents applicable as skin decontaminants have become available in non-nuclear industries such as cosmetics and sanitation. They are easily acquired and have an advantage in that stimulus to the skin is mild, because these products have been developed for the human body. In this study, the decontamination factor of the commercial detergents for each nuclide was examined using imitation skin. Sheets of raw pig skins were contaminated with a nitric-acid solution containing 144 Ce, 137 Cs, 106 Ru or 60 Co, and then washed with various detergents such as a neutral detergent, cleansing cream and orange oil. The nuclide removal rates of some of the commercial detergents examined were nearly equal to that of titanium dioxide, thus proving that they show satisfactory decontamination performance as a skin decontaminant. (author)

  2. Fighting Ebola with novel spore decontamination technologies for the military.

    Science.gov (United States)

    Doona, Christopher J; Feeherry, Florence E; Kustin, Kenneth; Olinger, Gene G; Setlow, Peter; Malkin, Alexander J; Leighton, Terrance

    2015-01-01

    Recently, global public health organizations such as Doctors without Borders (MSF), the World Health Organization (WHO), Public Health Canada, National Institutes of Health (NIH), and the U.S. government developed and deployed Field Decontamination Kits (FDKs), a novel, lightweight, compact, reusable decontamination technology to sterilize Ebola-contaminated medical devices at remote clinical sites lacking infra-structure in crisis-stricken regions of West Africa (medical waste materials are placed in bags and burned). The basis for effectuating sterilization with FDKs is chlorine dioxide (ClO2) produced from a patented invention developed by researchers at the US Army Natick Soldier RD&E Center (NSRDEC) and commercialized as a dry mixed-chemical for bacterial spore decontamination. In fact, the NSRDEC research scientists developed an ensemble of ClO2 technologies designed for different applications in decontaminating fresh produce; food contact and handling surfaces; personal protective equipment; textiles used in clothing, uniforms, tents, and shelters; graywater recycling; airplanes; surgical instruments; and hard surfaces in latrines, laundries, and deployable medical facilities. These examples demonstrate the far-reaching impact, adaptability, and versatility of these innovative technologies. We present herein the unique attributes of NSRDEC's novel decontamination technologies and a Case Study of the development of FDKs that were deployed in West Africa by international public health organizations to sterilize Ebola-contaminated medical equipment. FDKs use bacterial spores as indicators of sterility. We review the properties and structures of spores and the mechanisms of bacterial spore inactivation by ClO2. We also review mechanisms of bacterial spore inactivation by novel, emerging, and established non-thermal technologies for food preservation, such as high pressure processing, irradiation, cold plasma, and chemical sanitizers, using an array of Bacillus

  3. Method of bituminization equipment decontamination

    International Nuclear Information System (INIS)

    Alexa, J.

    1982-01-01

    Overheated water vapour is fed into the contaminated area containing substances insoluble in water but soluble in organic solvents. Prior to entry into the decontaminated area the vapour bubbles through the aqueous solution layer of suitable detergents and a layer of suitable organic solvent. In this process the distillation takes place of the solvent and the aerosols of the aqueous solution are carried away with the vapour stream, condense on the inner surface of the vessel and thus wash it. The condensate flows down the walls and in its place condense other fractions of pure solvent and the aqueous solution. The walls of the vessel are slowly heated and the liquid waste is discharged via a mud discharge pipe. (J.B.)

  4. Decontamination and partial dismantling of the Eurochemic plant. Part 1

    International Nuclear Information System (INIS)

    Detilleux, E.; Geens, L.; Hild, W.; Klonk, W.

    1980-09-01

    A description is given of the partial dismantling of the dissolver used for fuel elements of up to 1.6 wt % 235 U enrichment, and of the total dismantling of the dissolver for highly enriched fuel elements. The corresponding head-end cells have been decontaminated, allowing prolonged interventions, either in view of refurbishing or complete dismantling. An assessment of required manpower, dose commitments, material consumption, and waste production for all operations is given. (author)

  5. Use of titanates in decontamination of defense waste

    International Nuclear Information System (INIS)

    Dosch, R.G.

    1978-06-01

    Sodium titanate, an inorganic ion exchange material, has been evaluated for use in a process to remove strontium from Defense Waste or other high-sodium, caustic solutions. Distribution coefficients on the order of 10 5 were observed at sub part per million concentrations of Sr, and the effects of other cation impurities and complexants in the waste were investigated. The preparation and general chemical properties of the exchange material are discussed. This information was used in developing a commercial source which has since supplied a 200 kg batch of the material for evaluation. In column ion exchange experiments with 85 Sr-doped simulated waste, decontamination factors of 500 or greater were observed in the first 2000 to 3500 bed volumes of effluent, depending on the impurities in the simulant. A -40 to +130 mesh range of sodium titanate powder was used as the baseline material, but a study to produce alternate forms of the titanate was carried in parallel. This has resulted in two materials which appear promising with respect to both simplification of handling and chemical properties. One of the materials is an agglomerated form of the titanate formed by extrusion pelletizing using water as a binder, and the second is a macroreticular organic anion resin which was loaded with 30 to 40% (by weight) of sodium titanate. The results of initial testing of these materials are discussed

  6. Low-level liquid waste decontamination by ion exchange

    International Nuclear Information System (INIS)

    Campbell, D.O.; Lee, D.D.; Dillow, T.A.

    1991-12-01

    Improved processes are being developed to treat contaminated liquid wastes that have been and continue to be generated at Oak Ridge National Laboratory. Both inorganic and organic ion-exchange methods have given promising results. Nickel and cobalt hexacyanoferrate(2) compounds are extremely selective for cesium removal, with distribution coefficients in excess of 10 6 and remarkable insensitivity to competition from sodium and potassium. They tend to lose effectiveness at pH > ∼11, but some formulations are useful for limited periods of time up to pH ∼13. Sodium titanate is selective for strontium removal at high pH. The separations are so efficient that simple batch processes can yield large decontamination factors while generating small volumes of solid waste. A resorcinol-based resin developed at the Savannah River Site gave superior cesium removal, compared with other organic ion exchangers; the distribution coefficient was limited primarily by competition from potassium and was nearly independent of sodium. The optimum pH was ∼12.5. It was much less effective for strontium removal, which was limited by competition from sodium. 8 refs., 6 figs., 9 tabs

  7. A high-performance hydroxyl-functionalized polymer of intrinsic microporosity for an environmentally attractive membrane-based approach to decontamination of sour natural gas

    KAUST Repository

    Yi, Shouliang; Ma, Xiaohua; Pinnau, Ingo; Koros, William J.

    2015-01-01

    Acid gases carbon dioxide (CO2) and hydrogen sulfide (H2S) are important and highly undesirable contaminants in natural gas, and membrane-based removal of these contaminants is environmentally attractive. Although removal of CO2 from natural gas

  8. A study on the decontamination of the gravels contaminated by uranium

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ukryang; Kim, Gyenam; Kim, Seungsoo; Moon, Jaikwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The amount of gravels contaminated by uranium is usually about 10% of the contaminated soil. Since such contaminated gravels show different kinds and volumes, it would cost a considerable amount of money if they are to be disposed of without going through any special process. Also, there has not been any particular way or technology for processing the gravels contaminated by uranium. Therefore, various fundamental experiments and researches have been carried out for the decontamination of the gravels contaminated by uranium. Through such experiments and researches, it has been possible to obtain some significant results. The acid cleaning process, which is based on the application of the soil cleaning method, can be regarded as one of the major ways used for decontamination. When the gravels contaminated by uranium are cleaned as they are, most of them tend to show an extremely-low level of decontamination. Therefore, it could be said that the inside of each gravel is also contaminated by uranium. As a result, the gravels contaminated by uranium need to be crushed before being cleaned, which would result in a higher level of efficiency for decontamination compared to the previous way. Therefore, it is more effective to crush the subject gravels before cleaning them in terms of decontamination. However, such test results can only be applied to the gravels contaminated by an average level of uranium concentration. Regarding the gravels showing a higher level of uranium concentration than the average, it is still necessary to carry out more researches. Therefore, this study focused on the level of efficiency for decontamination after the contaminated gravels were crushed before being cleaned, in order to find a way to effectively dispose of the gravels contaminated by high-concentration uranium and secure a high level of efficiency for decontamination. In order to decontaminate the gravels which were contained in the soil contaminated by uranium and showed a higher

  9. Decontamination of liquid radioactive waste by thorium phosphate

    International Nuclear Information System (INIS)

    Rousselle, J.; Grandjean, S.; Dacheux, N.; Genet, M.

    2004-01-01

    In the field of the complete reexamination of the chemistry of thorium phosphate and of the improvement of the homogeneity of Thorium Phosphate Diphosphate (TPD, Th 4 (PO 4 ) 4 P 2 O 7 ) prepared at high temperature, several crystallized compounds were prepared as initial powdered precursors. Due to the very low solubility products associated to these phases, their use in the field of the efficient decontamination of high-level radioactive liquid waste containing actinides (An) was carefully considered. Two main processes (called 'oxalate' and 'hydrothermal' chemical routes) were developed through a new concept combining the decontamination of liquid waste and the immobilization of the actinides in a ceramic matrix (TPD). In phosphoric media ('hydrothermal route'), the key-precursor was the Thorium Phosphate Hydrogen Phosphate hydrate (Th 2 (PO 4 ) 2 (HPO 4 ). H 2 O, TPHP, solubility product log(K S,0 0 ) ∼ - 67). The replacement of thorium by other tetravalent actinides (U, Np, Pu) in the structure, leading to the preparation of Th 2-x/2 An x/2 (PO 4 ) 2 (HPO 4 ). H 2 O solid solutions, was examined. A second method was also considered in parallel to illustrate this concept using the more well-known precipitation of oxalate as the initial decontamination step. For this method, the final transformation to single phase TPD containing actinides was purchased by heating a mixture of phosphate ions with the oxalate precipitate at high temperature. (authors)

  10. Method of processing decontaminating liquid waste

    International Nuclear Information System (INIS)

    Kusaka, Ken-ichi

    1989-01-01

    When decontaminating liquid wastes are processed by ion exchange resins, radioactive nuclides, metals, decontaminating agents in the liquid wastes are captured in the ion exchange resins. When the exchange resins are oxidatively deomposed, most of the ingredients are decomposed into water and gaseous carbonic acid and discharged, while sulfur ingredient in the resins is converted into sulfuric acid. In this case, even less oxidizable ingredients in the decontaminating agent made easily decomposable by oxidative decomposition together with the resins. The radioactive nuclides and a great amount of iron dissolved upon decontamination in the liquid wastes are dissolved in sulfuric acid formed. When the sulfuric acid wastes are nuetralized with sodium hydroxide, since they are formed into sodium sulfate, which is most popular as wastes from nuclear facilities, they can be condensated and solidified by existent waste processing systms to thereby facilitate the waste processing. (K.M.)

  11. Method of decontaminating radioactive-contaminated instruments

    International Nuclear Information System (INIS)

    Urata, Megumu; Fujii, Masaaki; Kitaguchi, Hiroshi.

    1982-01-01

    Purpose: To enable safety processing of liquid wastes by recovering radioactive metal ions remaining in the electrolytes after the decontamination procedure thereby decreasing the radioactivity. Method: In a decontamination tank containing electrolytes consisting of diluted hydrochloric acid and diluted sulfuric acid, are provided a radioactive contaminated instrument connected to an anode and a collector electrode made of stainless steel connected to a cathode respectively. Upon applying electrical current, the portion of the mother material to be decontaminated is polished electrolytically into metal ions and they are deposited as metal on the collection electrode. After completion of the decontamination, an ultrasonic wave generator is operated to strip and remove the oxide films. Thereafter, the anode is replaced with the carbon electrode and electrical current is supplied continuously, whereby the remaining metal ions are deposited and recovered as the metal on the collection electrode. (Yoshino, Y.)

  12. Urban Decontamination Experience at Pripyat Ukraine - 13526

    Energy Technology Data Exchange (ETDEWEB)

    Paskevych, Sergiy [Institute for Safety Problems of Nuclear Power Plants, National Academy of Sciences of Ukraine, 36 a Kirova str. Chornobyl, Kiev region, 07200 (Ukraine); Voropay, Dmitry [Federal State Unitary Enterprise ' Russian State Center of Inventory and Registration and Real Estate - Federal Bureau of Technical Inventory' , 37-2 Bernadsky Prospekt, Moscow Russia 119415 (Russian Federation); Schmieman, Eric [Battelle Memorial Institute, PO Box 999 MSIN K6-90, Richland, WA 99352 (United States)

    2013-07-01

    This paper describes the efficiency of radioactive decontamination activities of the urban landscape in the town of Pripyat, Ukraine. Different methods of treatment for various urban infrastructure and different radioactive contaminants are assessed. Long term changes in the radiation condition of decontaminated urban landscapes are evaluated: 1. Decontamination of the urban system requires the simultaneous application of multiple methods including mechanical, chemical, and biological. 2. If a large area has been contaminated, decontamination of local areas of a temporary nature. Over time, there is a repeated contamination of these sites due to wind transport from neighboring areas. 3. Involvement of earth-moving equipment and removal of top soil by industrial method achieves 20-fold reduction in the level of contamination by radioactive substances, but it leads to large amounts of waste (up to 1500 tons per hectare), and leads to the re-contamination of treated areas due to scatter when loading, transport pollutants on the wheels of vehicles, etc.. (authors)

  13. Testing and comparison of seventeen decontamination chemicals

    International Nuclear Information System (INIS)

    Demmer, R.L.

    1996-09-01

    This report details the testing and evaluation of seventeen decontamination chemicals. Tests were conducted with SIMCON (simulated contamination) coupons under controlled conditions to compare cleaning effectiveness, overall corrosion potential for plant equipment, interim waste generation and final waste generation

  14. Method of decontaminating radioactive-contaminated instruments

    Energy Technology Data Exchange (ETDEWEB)

    Urata, M; Fujii, M; Kitaguchi, H

    1982-03-29

    Purpose: To enable safety processing of liquid wastes by recovering radioactive metal ions remaining in the electrolytes after the decontamination procedure thereby decreasing the radioactivity. Method: In a decontamination tank containing electrolytes consisting of diluted hydrochloric acid and diluted sulfuric acid, are provided a radioactive contaminated instrument connected to an anode and a collector electrode made of stainless steel connected to a cathode respectively. Upon applying electrical current, the portion of the mother material to be decontaminated is polished electrolytically into metal ions and they are deposited as metal on the collection electrode. After completion of the decontamination, an ultrasonic wave generator is operated to strip and remove the oxide films. Thereafter, the anode is replaced with the carbon electrode and electrical current is supplied continuously, whereby the remaining metal ions are deposited and recovered as the metal on the collection electrode.

  15. The CREATIVE Decontamination Performance Evaluation Model

    National Research Council Canada - National Science Library

    Shelly, Erin E

    2008-01-01

    The project objective is to develop a semi-empirical, deterministic model to characterize and predict laboratory-scale decontaminant efficacy and hazards for a range of: chemical agents (current focus on HD...

  16. Enzymatic Decontamination of Chemical Warfare Agents

    National Research Council Canada - National Science Library

    Raushel, Frank

    2000-01-01

    The primary objective of this research program is the development of a versatile enzyme-based system that is fully optimized for the decontamination, destruction, and detection of know chemical warfare agents...

  17. Decontamination method for radiation contaminated metal

    International Nuclear Information System (INIS)

    Enda, Masami; Hosaka, Katsumi; Sakai, Hitoshi.

    1997-01-01

    An organic acid solution is used as a decontamination liquid, and base materials of radiation contaminated metals are dissolved in the solution. The concentration of the organic acid is measured, and the organic acid is supplied by an amount corresponding to the lowering of the concentration. The decontamination liquid wastes generated during the decontamination step are decomposed, and metals leached in the organic acid solution are separated. With such procedures, contamination intruded into the inside of the mother materials of the metals can be removed, and radioactivity of the contaminated metals such as stainless steels and carbon steels can be eliminated, or the radiation level thereof can be reduced. In addition, the amount of secondary wastes generated along with the decontamination can be suppressed. (T.M.)

  18. Chemical decontamination method for stainless steel

    International Nuclear Information System (INIS)

    Yomo, Nobuo; Onuma, Tsutomu; Akimoto, Hidetoshi.

    1991-01-01

    In a case where an object to be decontaminated has a restricted portion in which the passage of liquids is difficult, decontamination liquids are not circulated effectively upon decontamination for the inner surfaces, and it requires a quite long period of time. In view of the above, through holes are perforated by, for example, a drill in the restricted portion of metal wastes made of stainless steels. Then, they are immersed in a sulfuric acid solution, and further immersed in an aqueous solution in which oxidative metal salts are added to the sulfuric acid. With such procedures, substrates are exposed at the inner circumference of the holes even if they are fine holes, and a local cell is formed between the substrate and an oxidized membranes, which may cause dissolution due to the reduction of the oxidized membranes. Further, since it is possible to discharge bubbles formed upon the solution, even from such fine holes, decontamination can be conducted effectively. (T.M.)

  19. Method of melt-decontaminating alumium contaminated with radioactivity

    International Nuclear Information System (INIS)

    Uda, Tatsuhiko; Iba, Hajime; Miura, Noboru; Kawasaki, Katsuo.

    1986-01-01

    Purpose: To enable optimum deontamination for radioactive-contaminated aluminum by further improving the decontaminating effect of the slag agent added to radioactive contaminated materials. Method: The slag agent is mainly composed of chloride type slags having a high reactivity for mainly incorporating uranium compounds and easily reacting near the melting point of aluminum and incorporated with fluorides for weakening the deliquescent characteristic to the chloride materials. Further, those slag agents are selected which can be treated at a low temperature in order to prevent the uranium compounds once incorporated into the slags from re-melting into the molten aluminum. Typically, a slag agent comprising 14 LiF, 76 KCl - 10 BaCl 2 is preferred. The basicity of the slag agent ranges from 0.5 to 2 and the melting point is 700 deg C. The melting decontaminating efficiency for the radioactive-contaminated aluminum can thus be improved. (Horiuchi, T.)

  20. Development of Decontamination Process for Soil Contaminated Uranium

    International Nuclear Information System (INIS)

    Kim, Gye-Nam; Kim, Seung-Soo; Park, Uk-Rang; Han, Gyu-Seong; Moon, Jei-Kwon

    2014-01-01

    Various experiments with full-scaled electrokinetic equipment, soil washing equipment, and gravel washing equipment were performed to remove 238 U from contaminated soils of below 0.4 Bq/g. The repetition number and the removal efficiencies of the soil and gravel washing equipment were evaluated. The decontamination periods by the soil and gravel electrokinetic equipment were evaluated. Finally, a work process of full-scaled decontamination equipment was developed. Contaminated soils were classified into soils and gravels using a 8.0 cm sieve. Soils were sent to the soil washing equipment, while gravels were sent to the gravel washing equipment. Soils sent to the soil washing equipment were sent to the soil electrokinetic equipment after soil washing. A repetition number of soil washing was two times. The washed gravels were sent to the gravel electrokinetic equipment. Gravel contaminated with a high concentration requires crushing after gravel washing