Surface decontamination using dry ice snow

International Nuclear Information System (INIS)

Ryu, Jungdong; Park, Kwangheon; Lee, Bumsik; Kim Yangeun

1999-01-01

An adjustable nozzle for controlling the size of dry ice snow was developed. The converging/diverging nozzle can control the size of snows from sub-microns to 10 micron size. Using the nozzle, a surface decontamination device was made. The removal mechanisms of surface contaminants are mechanical impact, partial dissolving and evaporation process, and viscous flow. A heat supply system is added for the prevention of surface ice layer formation. The cleaning power is slightly dependent on the size of snow. Small snows are the better in viscous flow cleaning, while large snows are slightly better in dissolving and sublimation process. Human oils like fingerprints on glass were easy to remove. Decontamination ability was tested using a contaminated pump-housing surface. About 40 to 80% of radioactivity was removed. This device is effective in surface-decontamination of any electrical devices like detector, controllers which cannot be cleaned in aqueous solution. (author)

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

Decontamination of material in the Marcoule plutonium producing centre (1961); La decontamination du materiel dans le centre de production du plutonium de Marcoule (1961)

Energy Technology Data Exchange (ETDEWEB)

Rodier, J; Bouzigues, H; Boutot, P [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

1961-07-01

The decontamination of material in an atomic centre is an essential operation in view of the cost and the difficulties of replacement. It also makes it possible to reduce the storage of radio-active materials always an expensive task. Surfaces are contaminated by retention of radioactive products and the mechanism of the bounding forces can be explained in terms of chemical, mechanical, electrostatic and surface tension phenomena. The methods used for decontamination are either physical (section, abrasion, steam, ultrasonics) or chemical (acids, alkalis, detergents, reducing and oxidising agents). At Marcoule, chemical methods of treatment are used. This is effected in tanks, the exact composition of the liquids being regulated from a control panel. Working experience has shown that the fact of operating in humid conditions eliminates all problems of atmospheric contamination; as a result it is possible for the personnel to work without any special protective devices. Almost all the material can be re-utilized and the operations produce only a small volume of liquid waste. The decontamination workshop is operated by a small number of workers. The working costs, including capital repayment and treatment of the waste, do not exceed 15 per cent of the value of the apparatus treated. (authors) [French] La decontamination du materiel dans un centre atomique est une operation indispensable etant donne le cout et les difficultes du remplacement. Elle contribue aussi a diminuer les stockages toujours onereux des materiaux radioactifs. Les surfaces se contaminent par retention de corps radioactifs, l'origine des forces de liaison devant etre recherchee dans les phenomenes chimiques, mecaniques, electro-statiques ou de tensions superficielles. Les methodes de decontamination peuvent etre physiques (aspiration, abrasion, vapeur, ultra-sons) ou chimiques (acides, alcalins, detergents, reducteurs, oxydants). Sur le centre de Marcoule, la methode des traitements chimiques a ete

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

Decontamination of lead by fusion (1962); Decontamination du plomb par fusion (1962)

Energy Technology Data Exchange (ETDEWEB)

Boutot, P; Giachetto, L; Capitaine, A [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

1962-07-01

Various attempts to decontaminate using mechanical and chemical methods having given questionable results, a fusion method has been developed. The apparatus consists of a propane-heated oven fitted with a steel crucible of 1 400 kg capacity, with two ventilation systems, and with a vacuum gauge for preventing the diffusion of toxic gases. There are three operational controls : 1. On the samples taken before during and after the operation, 2. On the plugs taken from the ingots, 3. On the ingot itself. The continuous sanitary control is done by a radioactive aerosol recorder and by periodic sampling. This decontamination process will be improved, especially as far as the productivity and the safety precautions are concerned. (authors) [French] Divers essais de decontamination par voies mecaniques et chimiques ayant donne des resultats discutables, un procede par fusion a ete mis au point. L'appareil se compose d'un four, chauffe au propane, muni d'un creuset en acier d'une capacite de 1 400 kg, de deux systemes de ventilation et d'un deprimometre afin d'eviter la diffusion de vapeurs nocives. Trois controles d'activite sont effectues: 1. sur des echantillons preleves avant, pendant et apres l'operation, 2. sur des carottages realises sur les lingots, 3. sur le lingot lui-meme. Le controle sanitaire permanent est assure par un enregistreur d'aerosols radioactifs et par des prelevements periodiques. Ce procede de decontamination doit encore etre ameliore, principalement en ce qui concerne la productivite et la securite. (auteurs)

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

Radioactive contamination of some rubber or plastic surfaces by fission products. Decontamination tests

International Nuclear Information System (INIS)

Mestre, E.; Sautiez, N.

1957-10-01

With the objective of notably addressing the contamination and decontamination of gloves and floor covering, this report first presents some characteristics of contaminating radioactive materials (nature, physical and chemical condition), of contaminated surfaces (surface condition, surface nature), and of decontamination processes (physical, chemical or mechanical action). It describes the operational modality implemented to test decontamination processes on various glove or flooring materials: sample preparation, counting, decontamination, reproducibility of decontamination tests, results in terms of activity reduction. It more precisely describes the tested samples: short gloves, gloves from glove boxes, floor and wall coverings. Results are presented and discussed in terms of sample susceptibility to contamination, and of decontamination, but also for re-contamination tests after a Nab-based decontamination (susceptibility to contamination, decontamination gain)

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

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

Floor surface decontaminating device for use in nuclear power plants

International Nuclear Information System (INIS)

Yoshida, Tomiji; Ue, Tatsuyuki; Omori, Nobuya; Okuzawa, Tsutomu.

1987-01-01

Purpose: To obtain a device for decontaminating the floor surfaces contaminated with radioactive materials in nuclear power plants or the likes, mechanically, automatically and effectively. Constitution: During running of the device by means of running wheels and castors, a decontaminating head is always applied with vibrations by a vibrator. In this state, wiping members are sent from a delivery roll, applied with vibrations at the decontaminating head. The members wipe off contamination products while in frictional contact with the floor surface and are then taken up to a winding roll with the contamination products deposited thereto. In this case, since the vibrations from the decontaminating head are transmitted by way of a resilient portion thereof to the wiping members, the vibrations transmitted from the wiping members to the floor surface are somewhat buffered. (Kawakami, Y.)

Decontamination tests on cotton materials; Essais de decontamination sur tissus de coton

Energy Technology Data Exchange (ETDEWEB)

Cohen, P; Pelletier, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

It is shown that versene gives the best decontamination results on cotton materials soiled by a mixture of fission products. (author) [French] On a montre que le versene donne les meilleurs resultats de decontamination sur des tissus de coton souilles par un melange de produits de fission. (auteur)

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

Determination of a cleaning and decontamination process using solvents; Determination d'une methode de nettoyage et de decontamination par solvant

Energy Technology Data Exchange (ETDEWEB)

Boutot, P; Schipfer, P [Commissariat a l' Energie Atomique, Chusclan (France). Centre de Production de Plutonium de Marcoule

1967-03-15

This work has been carried out on samples of the white cotton serge material of which most of the working overalls of the Nuclear Research Centre are made. The aims are: - to determine,from the decontamination and cleaning points of view, the efficiency of various solvents (white-spirit, trichloroethylene, perchlorethylene and tri-chloro-trifluoroethane) and the role of additives likely to improve the treatment; - to control the textile from the wear and shrinkage points of view; - to try to develop a basic cleaning and decontamination process as a function of the possibilities of each solvent considered. (authors) [French] Cette experimentation pratiquee sur des echantillons de tissu en serge de coton blanc, tissu dans lequel est confectionnee la majorite des tenues de travail du Centre, a pour but: - de determiner, sous l'angle decontamination et nettoyage, l'efficacite de differents solvants (white-spirit, trichlorethylene, perchlorethylene et trichlorotrifluoroethane) ainsi que le role des adjuvants susceptibles d'ameliorer le traitement; - de controler le textile du point de vue usure et retrecissement; - d'essayer de mettre au point un procede de nettoyage et de decontamination type en fonction des possibilites d'emploi de chacun des solvants consideres. (auteurs)

Low-waste electrochemical decontamination of stainless-steel surface

International Nuclear Information System (INIS)

Babain, V.A.; Smirnov, I.V.; Shadrin, A.Yu.; Firsin, N.G.; Zakharchuk, G.A.; Pavlov, A.B.; Shilov, V.V.

2002-01-01

An electrochemical decontamination method using a formic acid-based recycling electrolyte was proposed to remove firmly fixed contaminants from stainless-steel surfaces. The following provisions make for minimisation of the amounts of waste: (i) use of specially designed electrodes with vacuum removal of spent electrolyte; (ii) inter-cycle removal of radionuclides from the electrolyte by using an inorganic sorbent; (iii) periodic regeneration of the spent electrolyte. the dissolved metals (Fe, Cr, Ni) being transformed into acidic phosphates; (iv) solidification of residues arising from the regeneration of the electrolyte and spent sorbent into iron-phosphate ceramics. The technology and equipment developed were used for decontamination of a plutonium glove-box. The level of surface contamination was reduced 100-fold in two decontamination cycles. The depth of metal skimming was 1.5 μ for the ceiling and walls and 4.5 μ for the table top. Each square meter of stainless-steel surface provides about 100 g of solid radioactive waste in the form of iron-phosphate ceramic blocks

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

Method and coating composition for protecting and decontaminating surfaces

Science.gov (United States)

Overhold, D C; Peterson, M D

1959-03-10

A protective coating useful in the decontamination of surfaces exposed to radioactive substances is described. This coating is placed on the surface before use and is soluble in water, allowing its easy removal in the event decontamination becomes necessary. Suitable coating compositions may be prepared by mixing a water soluble carbohydrate such as sucrose or dextrin, together with a hygroscopic agent such as calcium chloride or zinc chloride.

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)

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)

Soil surface decontamination and revegetation progress

International Nuclear Information System (INIS)

Graves, A.W.

1981-01-01

A review is given of work by Rockwell Hanford Operations related to large-area decontamination efforts. Rockwell has a Program Office which manages the decontamination and decommissioning (D and D) efforts. Part of the program is involved with large-surface area cleanup in conjunction with surveillance and maintenance of retired sites and facilities. The other part is the decontamination and decommissioning of structures. There are 322 surplus contaminated sites and facilities for which Rockwell has responsibility on the Hanford Site. A Program Office was established for a disciplined approach to cleanup of these retired sites. There are three major projects: the first is surveillance and maintenance of the sites prior to D and D, the project under which the radiation area cleanup is contained. Another project is for contaminated-equipment volume reduction; size reduction with arc saw cut-up and volume reduction with a vacuum furnace meltdown are being used. The third major project is structural D and D

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.

Surface decontamination studies using polyvinyl acetate based strippable polymer

International Nuclear Information System (INIS)

Rao, S.V.S.; Lal, K.B.

2004-01-01

Polyvinyl acetate based strippable polymer has been developed for surface decontamination. Stainless steel, mild steel, polyvinyl chloride and rubber have been selected as candidate materials for the radioactive decontamination studies. The ease of strippability and homogeneity of the polymer coating has been studied using infrared spectrophotometer. Decontamination of used radioactive respirator has been carried out and the peels obtained have been subjected to leaching and incineration studies. The infrared spectrophotometric studies also have been conducted to study the interaction between polyvinyl acetate and ions, like cesium, strontium and cobalt. (author)

Radioactivity decontamination of materials commonly used as surfaces in general-purpose radioisotope laboratories.

Science.gov (United States)

Leonardi, Natalia M; Tesán, Fiorella C; Zubillaga, Marcela B; Salgueiro, María J

2014-12-01

In accord with as-low-as-reasonably-achievable and good-manufacturing-practice concepts, the present study evaluated the efficiency of radioactivity decontamination of materials commonly used in laboratory surfaces and whether solvent spills on these materials affect the findings. Four materials were evaluated: stainless steel, a surface comprising one-third acrylic resin and two-thirds natural minerals, an epoxy cover, and vinyl-based multipurpose flooring. Radioactive material was eluted from a (99)Mo/(99m)Tc generator, and samples of the surfaces were control-contaminated with 37 MBq (100 μL) of this eluate. The same procedure was repeated with samples of surfaces previously treated with 4 solvents: methanol, methyl ethyl ketone, acetone, and ethanol. The wet radioactive contamination was allowed to dry and then was removed with cotton swabs soaked in soapy water. The effectiveness of decontamination was defined as the percentage of activity removed per cotton swab, and the efficacy of decontamination was defined as the total percentage of activity removed, which was obtained by summing the percentages of activity in all the swabs required to complete the decontamination. Decontamination using our protocol was most effective and most efficacious for stainless steel and multipurpose flooring. Moreover, treatment with common organic solvents seemed not to affect the decontamination of these surfaces. Decontamination of the other two materials was less efficient and was interfered with by the organic solvents; there was also great variability in the overall results obtained for these other two materials. In expanding our laboratory, it is possible for us to select those surface materials on which our decontamination protocol works best. © 2014 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Vehicle for surface decontamination by electropolishing

International Nuclear Information System (INIS)

Maury, A.

1984-01-01

The invention concerns a remote controlled, electric powered vehicle for continuous decontamination of several supports forming an angle for instance the bottom and the walls of nuclear swimming pools. The vehicle is provided with all the means required for electropolishing (electrolyte, pumps, effluent recovery etc...) and two electropolishing units, one under the vehicle for horizontal surface treatment the other adjustable in height on a bracket for vertical surface treatment [fr

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

Comprehensive investigation of the corrosion and surface chemical effects of the decontamination technologies

International Nuclear Information System (INIS)

Szabo-Nagy, Andrea; Varga, Kalman; Deak-Horvath, Emese; Nemeth, Zoltan; Horvath, David; Schunk, Janos; Patek, Gabor

2012-09-01

Decontamination technologies are mainly developed to reduce the collective dose of the maintenance personnel at NPPs. The highest efficiency (i.e., the highest DF values) available without detrimental modification of the treated surface of structural material is the most important goal in the course of the application of a decontamination technology. A so-called 'soft' chemical decontamination technology has been developed - supported by the Paks Nuclear Power Plant - at the Institute of Radiochemistry and Radioecology of the University of Pannonia. The novel base technology can be effectively applied for the decontamination of the heat exchanger tubes of steam generators. In addition, by optimizing the main technological parameters (temperature, concentration of the liquid chemicals, flow rates, contact time, etc.) it can be utilized for specific applications such as decontamination of some dismountable devices and separable equipment or the total decontamination prior to plant dismantling (decommissioning) in the future. The aim of this work is to compare the efficiency, corrosion and surface chemical effects of some improved versions of the novel base-technology elaborated for decontamination of austenitic stainless steel surfaces. The experiments have been performed at laboratory conditions in decontamination model systems. The applied methods: γ-spectrometry, ICP-OES, voltammetry and SEM-EDX. The experimental results revealed that the efficiency of the base-technology mainly depends on the surface features of the stainless steel samples such as the chemical composition and thickness of the oxide layer, the nature (quantity, morphology and chemical composition) of the crystalline deposits. It has been documented that the improved version of the base-technology are suitable for the decontamination of both steel surfaces covered by chemically resistant large Cr-content crystals and that having compact oxide-layers (up to a thickness of 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.)

Application of a modified electrochemical system for surface decontamination of radioactive metal waste

International Nuclear Information System (INIS)

Lee, J.H.; Lim, Y.K.; Yang, H.Y.; Shin, S.W.; Song, M.J.

2003-01-01

Conventional and modified electrolytic decontamination experiments were performed in a solution of sodium sulfate for the decontamination of carbon steel as the simulated metal wastes which are generated in large amounts from nuclear power plants. The effect of reaction time, current density and concentration of electrolytes in the modified electrolytic decontamination system were examined to remove the surface contamination of the simulated radioactive metal wastes. As for the results of this research, the modified electrochemical decontamination process can decontaminate more effectively than the conventional decontamination process by applying different anode material which causes higher induced electro-motive forces. When 0.5 M sodium sulfate, 0.4 A/cm 2 current density and 30 minutes reaction time were applied in the modified process, a 16 μm thickness change that is expected to remove most surface contamination in radioactive metal wastes was achieved on carbon steel which is the main material of radioactive metal waste in nuclear power plants. The decontamination efficiency of metal waste showed similar results with the small and large lab-scale modified electrochemical system. The application of this modified electrolytic decontamination system is expected to play a considerable role for decontamination of radioactive metal waste in nuclear power plants in the near future. (author)

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)

Decontamination process and device of a radioactive surface with a coherent light beam. Procede et installation de decontamination d'une surface radioactive au moyen d'un faisceau de lumiere coherente

Energy Technology Data Exchange (ETDEWEB)

Gauchon, J.P.; Bournot, P.; Caminat, P.; Dupont, A.

1994-07-29

To decontaminate a radioactive surface, this one is swept with a focused laser beam and a liquid such as water or preferably a nitric acid solution on the whole surface. The liquid may be a film running on the surface and is recycled advantageously. The resulting decontamination is very efficient. 6 refs., 2 figs., 5 tabs.

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

Decontamination Efficiency of Fish Bacterial Flora from Processing Surfaces

Directory of Open Access Journals (Sweden)

Birna Guðbjörnsdóttir

2009-01-01

Full Text Available There are numerous parameters that can influence bacterial decontamination during washing of machinery and equipment in a food processing establishment. Incomplete decontamination of bacteria will increase the risk of biofilm formation and consequently increase the risk of pathogen contamination or prevalence of other undesirable microorganisms such as spoilage bacteria in the processing line. The efficiency of a typical washing protocol has been determined by testing three critical parameters and their effects on bacterial decontamination. Two surface materials (plastic and stainless steel, water temperatures (7 and 25 °C and detergent concentrations (2 and 4 % were used for this purpose in combination with two types of detergents. Biofilm was prepared on the surfaces with undefined bacterial flora obtained from minced cod fillets. The bacterial flora of the biofilm was characterised by cultivation and molecular analysis of 16S rRNA genes. All different combinations of washing protocols tested were able to remove more than 99.9 % of the bacteria in the biofilm and reduce the cell number from 7 to 0 or 2 log units of bacteria/cm2. The results show that it is possible to use less diluted detergents than recommended with comparable success, and it is easier to clean surface material made of stainless steel compared to polyethylene plastic.

Decontamination of radioactively contaminated surfaces - Method for testing and assessing the ease of decontamination (International Standard Publication ISO 8690:1988)

International Nuclear Information System (INIS)

Stefanik, J.

2001-01-01

The specifications laid down in this International Standard apply to the testing of surfaces which may become contaminated by radioactive materials. Decontaminability data obtained using this test method are not applicable to technical systems where layers of contaminating materials are formed as a result of long-term application of higher temperatures and pressures (for example primary circuits of nuclear reactors). The purpose of the test is to assess the ease of decontamination of surfaces under laboratory conditions. In practical applications, it may be important to consider other qualities, such as chemical, mechanical and radiation resistance and long-term stability in the selection of the materials to be used. It should be recognized that further decontamination tests under simulated service conditions may be needed

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.

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

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.)

The decontamination of soft-plated nickel surfaces compared to alternative surface materials used in radioactive transport and storage containers

International Nuclear Information System (INIS)

Zwicky, H.U.; Bedenig, D.O.; Bohringer, I.M.; Petrik, F.

1983-01-01

Surfaces of raw, nickel-plated, and epoxy-coated spheroidal graphite cast iron, together with stainless steel, were contaminated with a modified fission product solution then conditioned by heat treatment. This was followed by a variety of simple decontamination techniques. It was shown that the ease of removal of contaminations similar to those expected on a dry storage container surface is significantly affected by the roughness of the surface. The raw cast iron surface was virtually impossible to significantly decontaminate. Highest decontamination factors were obtained on nickel-plated and epoxy-painted surfaces using steam/detergent mixtures. Stainless steel only performed well in a polished condition. In a supplementary irradiation experiment, scanning electron microscopy indicated visible decomposition of an epoxy-painted surface at a gamma dose of 3.1 X 10 6 Gy (3.1 X 10 8 rad). A nickel-plated surface did not undergo any visible changes at the same dose

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

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.

Effects of ground surface decontamination on the air radiation dose rate. Results of a decontamination trial at a playground lot in a Fukushima residential area

International Nuclear Information System (INIS)

Tagawa, Akihiro

2012-01-01

The Japan Atomic Energy Agency decontaminated schools, playgrounds, swimming pools, and houses in nonevacuated, less-contaminated areas in Fukushima for environmental restoration. A small, 150 m 2 playground lot in the residential area was chosen for decontamination demonstration, which used routinely available tools and commodities to carry out the work. The surfaces of playground lot equipment, such as swings, slides, and horizontal iron bars, were completely decontaminated by brushing with water and/or detergent. Side gutters around the playground lot were cleaned by removing the mud and then brushed and washed with a high-pressure water jet (7 MPa). The air dose rate at the playground lot was dominated by radiation from the ground surface and adjacent surroundings, such as apartments and rice fields. Two or three centimeters of the surface soil contaminated with cesium was removed manually with shovels, hoes, and other gardening tools. This significantly reduced the average air dose rate of the entire playground lot from 1.5 μSv/h before decontamination to 0.6 μSv/h. These results showed that ground surface decontamination can contribute measurably to the reduction in air dose rate in relatively small areas in residential areas. (author)

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

Influence of Decontaminating Agents and Swipe Materials on Laboratory Simulated Working Surfaces Wet Spilled with Sodium Pertechnetate.

Science.gov (United States)

Akchata, Suman; Lavanya, K; Shivanand, Bhushan

2017-01-01

Decontamination of various working surfaces with sodium pertechnetate minor spillage is essential for maintaining good radiation safety practices as well as for regulatory compliance. To observe the influences of decontaminating agents and swipe materials on different type of surfaces used in nuclear medicine laboratory work area wet spilled with 99m-technetium (99mTc) sodium pertechnetate. Lab-simulated working surface materials. Experimental study design. Direct decontamination method on dust-free lab simulated new working surfaces [stainless steel, polyvinyl chloride (PVC), Perspex, resin] using four decontaminating agents [tap water, soap water (SW), Radiacwash, and spirit] with four different swipe material [cotton, tissue paper (TP), Whatman paper (WP), adsorbent sheet (AS)] was taken 10 samples (n = 10) for each group. Parametric test two-way analysis of variance is used with significance level of 0.005, was used to evaluate statistical differences between different group of decontaminating agent and swipe material, and the results are expressed in mean ± SD. Decontamination factor is calculated after five cleaning for each group. A total of 160 samples result calculated using four decontaminating agent (tap water, SW, Radiacwash, and spirit), four swipe material (cotton, TP, WP, and AS) for commonly used surface (stainless steel, PVC, Perspex, resin) using direct method by 10 samples (n = 10) for each group. Tap water is the best decontaminating agent compared with SW, Radiac wash and spirit for the laboratory simulated stainless steel, PVC, and Perspex surface material, whereas in case of resin surface material, SW decontaminating agent is showing better effectiveness. Cotton is the best swipe material compared to WP-1, AS and TP for the stainless steel, PVC, Perspex, and resin laboratory simulated surface materials. Perspex and stainless steel are the most suitable and recommended laboratory surface material compared to PVC and resin in nuclear medicine

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)

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.

Bioinspired Surface Treatments for Improved Decontamination: Handling andDecontamination Considerations

Science.gov (United States)

2018-03-16

and Decontamination Considerations Brandy J. White Martin H. Moore Brian J. Melde Laboratory for the Study of Molecular Interfacial Interactions...Decontamination Considerations Brandy J. White, Martin H. Moore, Brian J. Melde, Anthony P. Malanoksi, and Chanté Campbell1 Center for Bio/Molecular

Surface Decontamination Studies of Cs-137 and Sr-85 Using Polymer Gel

International Nuclear Information System (INIS)

Pham, L.; Nguyen, C.; Nguyen, L.

2015-01-01

Strippable polymer coating is one of the methods for effective surface decontamination to remove isotopes on the contaminated surface. This method is applying in nuclear facilities on the World. In this paper, we present the results obtained in our laboratory from product the polymer coating to apply to remove radioisotopes of "1"3"7Cs and "8"5Sr from surface of glass, stainless steel, mild steel, ceramic, PVC plastic. This polymer gel solution consist of water soluble polymer preferably polyvinyl alcohol (PVA), plasticizing agent (glycerine) and chelating agents, (citric acid) which can be sprayed or pasted on to contaminated surface. After some hours, these gel solutions was dried to form a strong thin film and it was easily peeled off from a contaminated surface with the radioactive isotopes and can be disposed off as radioactive solid waste. In this study infrared spectrophotometry technique was used to examine the interaction of the cesium and strontium ions with polyvinyl alcohol (PVA), polymer gel and the results of the study were also presented. The results showed that decontamination efficiency of "1"3"7Cs and "8"5Sr strongly depended on property, porosity and smoothness of the contaminated surface and obtained from 95-99% on glass and stainless steel, ceramic and PVC plastic surfaces. The decontamination efficiency also depended on activity and coating thickness. Optimization of film thickness is around 0.2 mm. Decontamination efficiency of Polymer gel were compared with Decongel 1101 (product from USA) on surfaces. IR spectra studies indicated that Cs and Sr ions interacted with PVA and citric acid in Polymer gel through cacboxyl (C = O) group. Polymer gel could remove of "1"3"7Cs and "8"5Sr better than PVA gel does because of citric acid, which can form chelating complex with Cs and Sr ion. (author)

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)

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)

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.)

Surface concrete decontamination equipment developed by Pacific Northwest Laboratory

International Nuclear Information System (INIS)

Halter, J.M.; Sullivan, R.G.; Bevan, J.L.

1982-08-01

This report documents a project that the Pacific Northwest Laboratory conducted to identify and develop techniques for removing contaminated concrete surfaces. A major problem associated with nuclear facility decontamination and decommissioning is how to economically demolish and dispose of contaminated concrete. Removing only the contaminated portion of the concrete can substantially reduce costs. Evaluation of various methods for removing concrete surfaces shows that several techniques presently used require excessive manpower, time, and energy. Many times more material is removed than necessary, increasing the quantity of waste that must be handled under controlled conditions. These evaluations generated the basic criteria for developing a suitable concrete removal technique: provide a convenient method for cleaning surfaces (such as those contaminated by a small spill); reduce the contaminated waste volume that has to be placed into controlled storage; remove surfaces quickly; and minimize personal exposure to potentially harmful radiation or toxic materials. Removal to 1/4 to 1/2 in. of contaminated surface layer is sufficient for cleanup of most facilities. Two unique decontamination methods have been developed: the concrete spaller and the water cannon. The concrete spaller is the most efficient technique: it removes the concrete surface faster than the water cannons and at a lower cost (as little as $3.00/ft 2 of concrete surface). However, the .458 magnum water cannon may be well suited for small or hard-to-reach locations

Metallic surfaces decontamination by using laser light

International Nuclear Information System (INIS)

Moggia, Fabrice; Lecardonnel, Xavier

2013-01-01

Metal surface cleaning appears to be one of the major priorities for industries especially for nuclear industries. The research and the development of a new technology that is able to meet the actual requirements (i.e. waste volume minimization, liquid effluents and chemicals free process...) seems to be the main commitment. Currently, a wide panel of technologies already exists (e.g. blasting, disk sander, electro-decontamination...) but for some of them, the efficiency is limited (e.g, Dry Ice blasting) and for others, the wastes production (liquid and/or solid) remains an important issue. One answer could be the use of a LASER light process. Since a couple of years, the Clean- Up Business Unit of the AREVA group investigates this decontamination technology. Many tests have been already performed in inactive (i.e. on simulants such as paints, inks, resins, metallic oxides) or active conditions (i.e. pieces covered with a thick metallic oxide layer and metallic pieces covered with grease). The paper will describe the results obtained in term of decontamination efficiency during all our validation process. Metallographic characterizations (i.e. SEM, X-ray scattering) and radiological analysis will be provided. We will also focus our paper on the future deployment of the LASER technology and its commercial use at La Hague reprocessing facility in 2013. (authors)

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.

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

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.)

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.)

Developmental Testing of Liquid and Gaseous/Vaporous Decontamination on Bacterial Spores and Other Biological Warfare Agents on Military Relevant Surfaces

Science.gov (United States)

2016-02-11

Vaporous Decontamination on Bacterial Spores and Other Biological Warfare Agents on Military-Relevant Surfaces 5a. CONTRACT NUMBER 5b. GRANT... DECONTAMINATION ON BACTERIAL SPORES AND OTHER BIOLOGICAL WARFARE AGENTS ON MILITARY-RELEVANT SURFACES Page Paragraph 1. SCOPE...surfaces before and after decontamination . The protocol in this TOP is based on the developed test methodologies from Edgewood Chemical Biological

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

Surface activity and radiation field measurements of the TMI-2 reactor building gross decontamination experiment

International Nuclear Information System (INIS)

McIsaac, C.V.

1983-10-01

Surface samples were collected from concrete and metal surfaces within the Three Mile Island Unit 2 Reactor Building on December 15 and 17, 1981 and again on March 25 and 26, 1982. The Reactor Building was decontaminated by hydrolasing during the period between these dates. The collected samples were analyzed for radionuclide concentration at the Idaho National Engineering Laboratory. The sampling equipment and procedures, and the analysis methods and results are discussed. The measured mean surface concentrations of 137 Cs and 90 Sr on the 305-ft elevation floor before decontamination were, respectively, 3.6 +- 0.9 and 0.17 +- 0.04 μCi/cm 2 . Their mean concentrations on the 347-ft elevation floor were about the same. On both elevations, walls were found to be considerably less contaminated than floors. The fractions of the core inventories of 137 Cs, 90 Sr, and 129 I deposited on Reactor Building surfaces prior to decontamination were calculated using their mean concentrations on various types of surfaces. The calculated values for these three nuclides are 3.5 +- 0.4 E-4, 2.4 +- 0.8 E-5, and 5.7 +- 0.5 E-4, respectively. The decontamination operations reduced the 137 Cs surface activity on the 305- and 347-ft elevations by factors of 20 and 13, respectively. The 90 Sr surface activity reduction was the same for both floors, that being a factor of 30. On the whole, decontamination of vertical surfaces was not achieved. Beta and gamma exposure rates that were measured during surface sampling were examined to determine the degree to which they correlated with measured surface activities. The data were fit with power functions of the form y = ax/sup b/. As might be expected, the beta exposure rates showed the best correlation. Of the data sets fit with the power function, the set of December 1981 beta exposure exhibited the least scatter. The coefficient of determination for this set was calculated to be 0.915

Decontamination tests using an electrolytic method on NS 22 S stainless steel discs (1963); Essais de decontamination par voie electrolytique de plaquettes en acier inoxydable NS 22 S (1963)

Energy Technology Data Exchange (ETDEWEB)

Boutot, P; Schipfer, P [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

1963-07-01

These tests were carried out with a view to observing the results obtained by using electrolytic polishing for the decontamination operations. The experimental equipment consists essentially of a current rectifier and adjuster, and of an electrolytic cell fitted with an automatic system for thermal regulation and agitation. The samples made of type NS 22 S stainless steel are contaminated with an active solution of fission products. The activity of the discs is measured before and after each treatment using a bell counter. For each electrolyte, the parameters studied are: - the time, - the reactant concentration, - the temperature, - the current density, - the corrosion. Taking into account the necessity of transforming as little as possible the surface of the part to be treated, the best results are generally obtained using intermediate concentrations of the reactant, low temperatures, and high current densities. (authors) [French] Ces essais ont ete effectues dans le but d'observer les resultats obtenus en utilisant le procede de polissage electrolytique pour les operations de decontamination. Le dispositif experimental consiste essentiellement en un redresseur-variateur de courant et en une cellule electrolytique munie d'un systeme automatique de regulation thermique et d'agitation. Les echantillons en acier inoxydable du type NS 22 S sont contamines par une solution active de produits de fission. L'activite des plaquettes est mesuree avant et apres chaque traitement au moyen d'un compteur cloche. Pour chaque electrolyte, les parametres etudies sont: - le temps, - la concentration du reactif, - la temperature, - la densite de courant, - la corrosion. En tenant compte de la necessite de transformer au minimum l'etat de surface de la piece a traiter, les resultats les meilleurs sont generalement obtenus pour des concentrations moyennes de reactif, des temperatures basses et des densites de courant elevees. (auteurs)

The Decontamination of Low-Level Radioactive Waste Water at Risoe Research Establishment; Decontamination des Eaux Residuaires de Faible Radioactivite au Centre de Recherche de Risoe; 0414 0415 0417 0410 ; La Descontaminacion de Aguas que Reciben Desechos Radiactivos de Baja Actividad, en el Centro de Investigaciones de Risoe

Energy Technology Data Exchange (ETDEWEB)

Larsen, Ib [Research Establishment Risoe, Danish Atomic Energy Commission (Denmark)

1960-07-01

Because of the low rate of water renewal in the recipient, Roskilde Fiord, an efficient decontamination plant incorporating an evaporator has been constructed at the Risoe research establishment. It is intended that the activity of the fiord-water at a distance of ten metres from the discharge point shall be less than one-tenth of the drinking-water tolerance. This will correspond to ca. 1 millicurie per month contained in ca. 5000 m{sup 3} of effluent. A description of the control and collection of laboratory effluents, of the decontamination plant and of the residue storage building will be given. The results of current experiments dealing with the decontamination factor and the economic aspects of the problem will also be given. (author) [French] Vu la lenteur du rythme de renouvellement des eaux dans le fjord de Roskilde, qui recoit les effluents du centre de recherche de Risoe, une installation efficace de decontamination, munie d'un evaporateur, a ete construite dans le centre. La radioactivite des eaux du fjord, a une distance de dix metres de l'orifice de vidange, devra rester inferieure au dixieme de la dose maximum admissible pour l'eau potable, ce qui correspond a une dose mensuelle approximative d'un millicurie pour environ 5.000 metres cubes d'effluents. Le memoire contient une description du controle et de la collecte des effluents du laboratoire, de l'installation de decontamination et du batiment servant a l'entreposage des residus. L'auteur expose en outre les resultats des experiences en cours sur le facteur de decontamination et sur les aspects economiques du probleme. (author) [Spanish] Debido al bajo indice de renovacion de las aguas en el fiordo de Roskildo, en el que se vierten los desechos radiactivos del Centro de Investigaciones de Risoe, se esta construyendo en el Centro una eficaz instalacion de descontaminacion de la que forma parte un evaporador. Se pretende con ello que la radiactividad de las aguas del fiordo, a una distancia de 10

Influence on proliferation and adhesion of human gingival fibroblasts from different titanium surface decontamination treatments: An in vitro study.

Science.gov (United States)

Cao, Jie; Wang, Tong; Pu, Yinfei; Tang, Zhihui; Meng, Huanxin

2018-03-01

To investigate the effects of different decontamination treatments on microstructure of titanium (Ti) surface as well as proliferation and adhesion of human gingival fibroblasts (HGFs). Ti discs with machined (M) and sand blasted, acid etched (SAE) surfaces were treated with five different decontamination treatments: (1) stainless steel curette (SSC), ultrasonic system with (2) straight carbon fiber tip (UCF) or (3) metal tip (UM), (4) rotating Ti brush (RTB), and (5) Er:YAG laser (30 mJ/pulse at 30 Hz). Surface roughness was analyzed under optical interferometry. HGFs were cultured on each disc. Proliferation and adhesive strength were analyzed. qRT-PCR and ELISA were performed to detect the RNA and protein expression of FAK, ITGB1, COL1A1, and FN1 respectively from different Ti surfaces. Surface roughness increased on M surface. Proliferation, adhesive strength and gene expression were higher on M surface than SAE surface. Decontamination treatments affected surface parameters significantly (P < 0.001), making M surface less smooth while SAE surface became less rough. SSC, UCF, UM and RTB decreased proliferation on M surfaces significantly (P < 0.05). UCF, RTB and laser increased proliferation on SAE surface significantly (P < 0.05). UM decreased adhesive strength on M surface significantly and laser increased adhesive strength on SAE surface significantly (P < 0.05). Gene expression increased with time and was altered by decontamination treatments significantly (P < 0.001). Decontamination treatments influence surface roughness and cell behavior of HGFs. Laser might be an optimal decontamination treatment which has the least negative effect on M surface and the most positive effect on SAE surface. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.)

Development of a robot for decontamination of reactor well and maintenance pit wall surfaces

International Nuclear Information System (INIS)

Miyakawa, Minoru; Nozawa, Katsuro; Mizutani, Takeshi; Onozuka, Kazuaki; Morita, Isamu

1984-01-01

A robot has been developed at Hamaoka BWR Power Plant of Chubu Electric Power Company, Inc., which performs the decontamination of the wall surfaces of reactor wells and maintenance pits. The robot is controlled with a control box through a micro-computer. The mechanical structure and working principle of this robot is explained. One of the special features of this robot is that it perceives the steps on a wall, and washes the vertical and horizontal surfaces with two different types of brushes. As the material for the bristles of the brushes, nylon with alumina as abrasive (TAINEX-A made by Dupont Ltd.) was selected after some experience. The design specifications of the brushes were determined, based on the results of intensive performance test, which are shown in this report. The efficiency of this robot was proved by applying it to the decontamination of the reactor wells in the periodic inspection and maintenance of Unit 1 and Unit 2 in the Hamaoka BWR Power Plant. As the result of this decontamination, the contamination level was reduced from about 10 -3 μCi/cm 2 to about 10 -5 μCi/cm 2 . The measured results of contamination after the first and third decontamination works are listed for various parts of the well surfaces. (Aoki, K.)

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.

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)

Laser techniques for radioactive decontamination gives metallic surfaces

International Nuclear Information System (INIS)

Escobar Alracon, L.; Molina, G.; Vizuet Gonzalez, J.

1998-01-01

In this work it presented the prototype for system decontamination at diverse component with removable superficial contamination, using the technique gives laser ablation, for the evaporation at the pollutant. It discusses the principle in the fact that system, as well as the different elements that compose it. The are presented the obtained results when irradiating with a laser a surface without radioactive contamination to verify the system operation

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

Development of a robot for decontamination of reactor well and maintenance pit wall surfaces

Energy Technology Data Exchange (ETDEWEB)

Miyakawa, Minoru; Nozawa, Katsuro; Mizutani, Takeshi; Onozuka, Kazuaki; Morita, Isamu

1984-03-01

A robot has been developed at Hamaoka BWR Power Plant of Chubu Electric Power Company, Inc., which performs the decontamination of the wall surfaces of reactor wells and maintenance pits. The robot is controlled with a control box through a micro-computer. The mechanical structure and working principle of this robot is explained. One of the special features of this robot is that it perceives the steps on a wall, and washes the vertical and horizontal surfaces with two different types of brushes. As the material for the bristles of the brushes, nylon with alumina as abrasive (TAINEX-A made by Dupont Ltd.) was selected after some experience. The design specifications of the brushes were determined, based on the results of intensive performance test, which are shown in this report. The efficiency of this robot was proved by applying it to the decontamination of the reactor wells in the periodic inspection and maintenance of Unit 1 and Unit 2 in the Hamaoka BWR Power Plant. As the result of this decontamination, the contamination level was reduced from 10/sup 3/ ..mu..Ci/cm/sup 2/ to about 10/sup 5/ ..mu..Ci/cm/sup 2/. The measured results of contamination after the first and third decontamination works are listed for various parts of the well surfaces.

A Nanosecond Pulsed Plasma Brush for Surface Decontamination

Science.gov (United States)

Neuber, Johanna; Malik, Muhammad; Song, Shutong; Jiang, Chunqi

2015-11-01

This work optimizes a non-thermal, atmospheric pressure plasma brush for surface decontamination. The generated plasma plumes with a maximum length of 2 cm are arranged in a 5 cm long, brush-like array. The plasma was generated in ambient air with Acinetobacter baumannii. Laminate surfaces inoculated with over-night cultured bacteria were subject to the plasma treatment for varying water concentrations in He, flow rates and discharge voltages. It was found that increasing the water content of the feed gas greatly enhanced the bactericidal effect. Emission spectroscopy was performed to identify the reactive plasma species that contribute to this variation. Additional affiliation: Frank Reidy Research Center for Bioelectrics

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.

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

Decontamination efficiency of a sheet of vinyl wall paper as a surface material in radioisotope laboratory

International Nuclear Information System (INIS)

Furukawa, Kazuhiko; Funadera, Kanako

1989-01-01

It has long been desired to prevent surface materials from cracking in a radioisotope laboratory. We applied a sheet of nonflammable wall paper, vinyl cloth, as a surface material to cover concrete wall. It was sufficiently resistant to the reinforced concrete wall cracking. The efficiency of the decontamination of the vinyl cloth was compared with those of stainless steel, iron and painted plates. The contamination and decontamination indices were determined in these surface materials after contamination with [ 32 P]orthophosphate (pH 3, 7 and 11) for 0 to 48 h. Both of the indices of the vinyl cloth were higher than those of the other materials. Further, it was confirmed that the vinyl cloth was resistant to acid and alkaline conditions and radioisotopes could not be permeable. The wipe off efficiency was also investigated in these materials by use of several decontamination detergents. In any reagents tested, the wipe of efficiency of the vinyl cloth was more than 80%. Thus, the vinyl cloth could be used for the surface material and is one of good surface materials in a radioisotope laboratory. (author)

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

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.)

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

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.)

Effect of the ODS-4 surfactant and its components on the efficiency of decontamination of solid surfaces

International Nuclear Information System (INIS)

Dvorak, J.; Duris, P.

1994-01-01

The efficiency was examined of the desorption of carrier-free traces of 147 Pm adsorbed from an acid aqueous solution at pH 2.6 in static conditions on a paint routinely applied to military facilities. The desorption was performed by using the ODS-4 decontamination and deactivation mixture and its components at various concentrations. It is concluded that the surfactant is not very well suited to the decontamination of solid surfaces contaminated with radionuclides which form the water-soluble component of radioactive contamination (in dependence on pH). This is due to the composition and the associated high alkalinity of the ODS-4 agent, which, however, is necessary if detoxication of toxic agents is required. In practice, however, the efficiency of decontamination will be appreciably higher because the military decontamination procedures involve dynamic (mechanical) treatment of the surfaces using brushes with flowing liquid, pressure application of the surfactant and water, moving baths, etc. (P.A.). 7 tabs., 2 figs., 10 refs

Study the polymer coating for detecting and surface decontamination of uranium

International Nuclear Information System (INIS)

Pham Thi Quynh Luong; Nguyen Van Chinh

2011-01-01

Strippable polymer coating is one of the methods for effective surface decontamination. It has been developed in both detecting and removing the radioactive isotope and heavy metal elements from contaminated surfaces. A polymer coating is produced to be sprayed or brushed on contaminated material of uranium. The places of U contamination is shown by color change of polymer coating. As the polymer coating is dried up to form a strong film, the contaminations are absorbed in to the coating and contaminated surfaces are cleaned by removing the film. (author)

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)

Studies on residue-free decontaminants for chemical warfare agents.

Science.gov (United States)

Wagner, George W

2015-03-17

Residue-free decontaminants based on hydrogen peroxide, which decomposes to water and oxygen in the environment, are examined as decontaminants for chemical warfare agents (CWA). For the apparent special case of CWA on concrete, H2O2 alone, without any additives, effectively decontaminates S-2-(diisopropylamino)ethyl O-ethyl methylphosphonothioate (VX), pinacolyl methylphosphorofluoridate (GD), and bis(2-choroethyl) sulfide (HD) in a process thought to involve H2O2 activation by surface-bound carbonates/bicarbonates (known H2O2 activators for CWA decontamination). A plethora of products are formed during the H2O2 decontamination of HD on concrete, and these are characterized by comparison to synthesized authentic compounds. As a potential residue-free decontaminant for surfaces other than concrete (or those lacking adsorbed carbonate/bicarbonate) H2O2 activation for CWA decontamination is feasible using residue-free NH3 and CO2 as demonstrated by reaction studies for VX, GD, and HD in homogeneous solution. Although H2O2/NH3/CO2 ("HPAC") decontaminants are active for CWA decontamination in solution, they require testing on actual surfaces of interest to assess their true efficacy for surface decontamination.

Antibacterial effect of hydrogen peroxide-titanium dioxide suspensions in the decontamination of rough titanium surfaces.

Science.gov (United States)

Wiedmer, David; Petersen, Fernanda Cristina; Lönn-Stensrud, Jessica; Tiainen, Hanna

2017-07-01

The chemical decontamination of infected dental implants is essential for the successful treatment of peri-implantitis. The aim of this study was to assess the antibacterial effect of a hydrogen peroxide-titanium dioxide (H 2 O 2 -TiO 2 ) suspension against Staphylococcus epidermidis biofilms. Titanium (Ti) coins were inoculated with a bioluminescent S. epidermidis strain for 8 h and subsequently exposed to H 2 O 2 with and without TiO 2 nanoparticles or chlorhexidine (CHX). Bacterial regrowth, bacterial load and viability after decontamination were analyzed by continuous luminescence monitoring, live/dead staining and scanning electron microscopy. Bacterial regrowth was delayed on surfaces treated with H 2 O 2 -TiO 2 compared to H 2 O 2 . H 2 O 2 -based treatments resulted in a lower bacterial load compared to CHX. Few viable bacteria were found on surfaces treated with H 2 O 2 and H 2 O 2 -TiO 2 , which contrasted with a uniform layer of dead bacteria for surfaces treated with CHX. H 2 O 2 -TiO 2 suspensions could therefore be considered an alternative approach in the decontamination of dental implants.

Surface deposition measurements of the TMI-2 gross decontamination experiment

International Nuclear Information System (INIS)

McIssac, C.V.; Hetzer, D.C.

1982-01-01

In order to measure the effectiveness of the gross decontamination experiment (principally a water spray technique) performed in the TMI-2 reactor building, the Technical Information and Examination Program's Radiation and Environment personnel made surface activity measurements before and after the experiment. In conjunction with surface sampling, thermoluminescent dosimeter (TLD) and gamma spectrometry measurements were also performed to distinguish between radiation fields and contamination. The surface sampler used to collect samples from external surfaces within the reactor building is a milling tool having four major components: a 1.27-cm constant-speed drill; a drill support assembly that allows setting sample penetration depth; filter cartridges for intake air purification and sample collection; and an air pump that forces air across the surface being sampled and through the sample filter cartridge

Experiment of decontamination of radioactive liquid by a biological method; Experience de decontamination de liquides radioactifs far voie biologique

Energy Technology Data Exchange (ETDEWEB)

Wormser, G.

1962-07-01

The author reports experiments of treatment of radioactive liquid effluents by percolation on a bacterial bed like the one used for the treatment of sewer wastewaters. He also reports results obtained in other countries in terms of reduction of effluent radioactivity for various radioactive ions. The installation is described and results are presented in terms of variation of contamination of an effluent with respect to its recycling on a bacterial bed [French] Dans le monde entier, on se preoccupe des moyens de decontamination pour des liquides radioactifs. Les experiences de l'auteur ont confirme qu'un lit bacterien neuf peut donner de bons resultats: il est a noter que ce procede biologique se montre selectif a l'egard des divers ions radioactifs. (auteur)

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

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.

Recovery of trans-plutonium elements; Recuperation des elements transplutoniens

Energy Technology Data Exchange (ETDEWEB)

Espie, J Y; Poncet, B; Simon, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1970-07-01

The object of this work is to study the recovery of americium and curium from the fission-product solution obtained from the processing of irradiated fuel elements made of natural metallic uranium alloyed with aluminium, iron and silicon; these elements have been subjected to an average irradiation of 4000 MW days/ton in a gas-graphite type reactor having a thermal power of 3.7 MW/ton of uranium. The process used consists of 3 extraction cycles and one americium-curium separation: - 1) extraction cycle in 40 per cent TBP: extraction of actinides and lanthanides; elimination of fission products; - 2) extraction cycle in 8 per cent D2EHPA: decontamination from the fission products, decontamination of actinides from lanthanides; - 3) extraction cycle in 40 per cent TBP: separation of the complexing agent and concentration of the actinides; - 4) americium-curium separation by precipitation. (authors) [French] Cette etude a pour objet, la recuperation de l'americium et du curium de la solution de produits de fission provenant du traitement de combustibles irradies a base d'uranium naturel metallique allie a l'aluminium, le fer, et le silicium, et ayant subi une irradiation moyenne de 4000 MWj/t dans une pile du type graphite-gaz, dont la puissance thermique est de 3.7 MW/t d'uranium. Le procede utilise comprend 3 cycles d'extraction et une separation americium-curium: - 1. cycle d'extraction dans le TBP a 40 pour cent: extraction des actinides et des lanthanides, elimination des produits de fission; - 2. cycle d'extraction dans le D2EHPA a 8 pour cent: decontamination en produits de fission, decontamination des actinides en lanthanides; - 3. cycle d'extraction dans le TBP a 40 pour cent: separation du complexant et concentration des actinides; - 4. separation americium-curium par precipitation. (auteurs)

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.)

Decontamination around the site of Chernobylsk; Decontamination autour du site de Tchernobyl

Energy Technology Data Exchange (ETDEWEB)

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.).

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)

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.)

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

Removal of radioactive cesium from surface soils solidified using polyion complex. Rapid communication for decontamination test at Iitate-mura in Fukushima Prefecture

International Nuclear Information System (INIS)

Naganawa, Hirochika; Yanase, Nobuyuki; Mitamura, Hisayoshi; Nagano, Tetsushi; Yoshida, Zenko; Kumazawa, Noriyuki; Saitoh, Hiroshi; Kashima, Kaoru; Fukuda, Tatsuya; Tanaka, Shun-ichi

2011-01-01

We tried the decontamination of surface soils for three types of agricultural land at Nagadoro district of Iitate-mura (village) in Fukushima Prefecture, which is highly contaminated by deposits of radionuclides from the plume released from the Fukushima Daiichi nuclear power plant. The decontamination method consisted of the peeling of surface soils solidified using a polyion complex, which was formed from a salt solution of polycations and polyanions. Two types of polyion complex solution were applied to an upland field in a plastic greenhouse, a pasture, and a paddy field. The decontamination efficiency of the surface soils reached 90%, and dust release was effectively suppressed during the removal of surface soils. (author)

Weathering and decontamination of radioactivity deposited on asphalt surfaces

International Nuclear Information System (INIS)

Warming, L.

1982-12-01

Longlived fission products might be deposited in the environment after a serious reactor accident. At Risoe we have studied how danish weather conditions and fire hosing influence the decontamination of Rubidium 86 (representing Cesium 134 and 137) Barium-Lanthanum 140 and Ruthenium 103 deposited on asphalt surfaces. Measurements have been done at different types of roads and during all seasons including winter with snow and ice cover of the roads. The results from the first five experiments were used for calculating doses to the population in the land contamination (RISO-R-462). (author)

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)

Decontamination analysis of a radiologically contaminated site

International Nuclear Information System (INIS)

Tawil, J.J.; Strenge, D.L.

1984-02-01

This paper presents an analysis of decontamination options at the NUWAZX-83 exercise site. Held in May 1983, the purpose of the exercise was to evaluate the ability of federal, state and local officials to respond to a radiological accident involving nuclear weapons. A computer program developed by Pacific Northwest Laboratory was used to conduct the decontamination analysis. The program, called DECON, was designed to assist personnel engaged in the planning of decontamination activities. The many features of DECON that are demonstrated in this paper contribute to its potential usefulness as a planning tool for site restoration. Strategies that are analyzed with DECON include: (1) using a Quick-Vac option, under which exterior surfaces are vacuumed before it rains; (2) protecting surfaces against precipitation; (3) prohibiting specific operations on selected surfaces; (4) requiring that specific methods be used on selected surfaces; (5) evaluating the trade-off between cleanup standards and decontamination costs; and (6) varying clean-up standards according to expected human exposure to the surface

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

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.)

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

Studies of decontamination using easy removable coatings technique

International Nuclear Information System (INIS)

Oglaza, J.; Nowak, Z.

1991-01-01

The usefulness of removable coatings for decontamination of steel and epoxy-resin painted surfaces was examined. Natural latex, Revultex, butadiene-styrene latex as well as mixtures of latex with complexing agents and surfactants were used as decontaminating coats. The best decontamination was obtained by removable coatings of natural latex with EDTA additive for all surfaces and radionuclides tested. (author). 16 refs, 5 tabs

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

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.

In vitro determination of skin decontamination efficacy using a water shower

International Nuclear Information System (INIS)

Reifenrath, W.G.

1990-01-01

The ability of a water shower to remove radioactivity from excised pig skin exposed to radiolabeled diisopropyl fluorophosphate and n-butyl 2-chloroethyl sulfide was determined. Skin samples were decontaminated 15 minutes after chemical exposures (1 mg/cm 2 ) and the distribution of radioactivity was determined 1 hour after decontamination. Compared to controls (no decontamination), shower decontamination reduced the evaporative loss of radioactivity from the skin surface after decontamination or reduced radioactive residues on the skin surface. Shower decontamination of skin at 15 minutes could not prevent penetration of radiolabel into the viable layers of skin or into fluid bathing the dermal surface of the skin, but was beneficial in reducing skin surface concentrations, which may lead to further exposure or contamination

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.)

Fuel decontamination at Ringhals 1 with the new decontamination process IcedecTM

International Nuclear Information System (INIS)

Fredriksson, E.; Ivars, R.; Rosengren, A.; Granath, G.

2003-01-01

The new fuel decontamination technique ICEDEC TM , which has been developed by Westinghouse, is based on abrasion of fuel crud with ice particles. A mixture of ice and water is led continuously through the fuel assembly, which is placed in a specially designed fuel decontamination container connected to a closed loop recirculation system. The ice particles scrape off the loose crud from the fuel surfaces and a mixture of crud and water from the melted ice is then led to a filter unit were the crud is separated from the water. In this paper results of fuel decontamination tests of two-year-old and spent fuel assemblies during spring 2001 at Ringhals 1 are presented. The fuel crud was only released when ice particles passed through the fuel assembly and stopped within ten seconds after the feeding of ice particles had ceased. The activity release from the fuel could thus be performed in a controlled way making the process easy to manage and survey. Activity measurements confirmed that about 50% of the loose crud was removed from the fuel surfaces of the two-year-old assembly. Fuel inspection after the decontamination process showed no influence on the fuel integrity. Furthermore, no enhanced personnel radiation dose was involved with the fuel decontamination compared to normal fuel services. (authors)

Electrolytic treatment of liquid effluents: decontamination by electro coagulation of release water of a petroleum platform; Traitement electrolytique des effluents liquides: decontamination par electrocoagulation des eaux de rejet d'une plate forme petroliere

Energy Technology Data Exchange (ETDEWEB)

Nanseu-Njiki, Ch.P.; Ngameni, E.; Poumiba, S. [Yaounde Univ., Laboratoire de Chimie Analytique, Dept. de Chimie Inorganique, Faculte des Sciences (Cameroon); Darchen, A. [Ecole Nationale Superieure de Chimie de Rennes, Laboratoire d' Electrochimie, 35 - Rennes (France)

2005-07-01

The water releases of petroleum platforms present lots of pollutants; Usually, these waters are reinjected in ground water when it is possible. In the other cases they are released at the surface and need then a treatment. The electro-coagulation is a suitable method often used. The authors propose to study the optimum conditions of decontamination by this method, by a parametric evaluation (water flow, charge density, ph). Experiments used iron and aluminium electrodes. (A.L.B.)

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

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.)

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)

Decontamination analysis of a radiologically contaminated site

International Nuclear Information System (INIS)

Tawil, J.J.; Strenge, D.L.

1984-01-01

This paper presents a post-exercise analysis of decontamination options for the NUWAX-83 exercise site. Held in May 1983, the purpose of NUWAX-83 was to evaluate the ability of federal, state and local officials to respond to an accident involving nuclear weapons. A computer program, called DECON, was developed by Pacific Northwest Laboratory and used to conduct the decontamination analysis in November 1983. DECON was designed to assist personnel engaged in the planning of decontamination activities. The many features of DECON that are demonstrated in this paper contribute to its potential usefulness as a planning tool for site restoration. Strategies that are analyzed with DECON include: 1) using a Quick-Vac option, under which exterior surfaces are vacuumed before it rains; 2) protecting surfaces against precipitation; 3) prohibiting specific operations on selected surfaces; 4) requiring that specific methods be used on selected surfaces; 5) evaluating the trade-off between cleanup standards and decontamination costs; and 6) varying clean-up standards according to expected human exposure to the surface

Low pressure plasma discharges for the sterilization and decontamination of surfaces

International Nuclear Information System (INIS)

Rossi, F; Rauscher, H; Hasiwa, M; Gilliland, D; Kylian, O

2009-01-01

The mechanisms of sterilization and decontamination of surfaces are compared in direct and post discharge plasma treatments in two low-pressure reactors, microwave and inductively coupled plasma. It is shown that the removal of various biomolecules, such as proteins, pyrogens or peptides, can be obtained at high rates and low temperatures in the inductively coupled plasma (ICP) by using Ar/O 2 mixtures. Similar efficiency is obtained for bacterial spores. Analysis of the discharge conditions illustrates the role of ion bombardment associated with O radicals, leading to a fast etching of organic matter. By contrast, the conditions obtained in the post discharge lead to much lower etching rates but also to a chemical modification of pyrogens, leading to their de-activation. The advantages of the two processes are discussed for the application to the practical case of decontamination of medical devices and reduction of hospital infections, illustrating the advantages and drawbacks of the two approaches.

Low pressure plasma discharges for the sterilization and decontamination of surfaces

Energy Technology Data Exchange (ETDEWEB)

Rossi, F; Rauscher, H; Hasiwa, M; Gilliland, D [European Commission, Joint Research Centre, Institute for Health and Consumer Protection, Via E. Fermi 2749, 21027 Ispra (Vatican City State, Holy See) (Italy); Kylian, O [Faculty of Mathematics and Physics, Charles University, V Holesovickach 2, Prague 8, 180 00 (Czech Republic)], E-mail: francois.rossi@jrc.ec.europa.eu

2009-11-15

The mechanisms of sterilization and decontamination of surfaces are compared in direct and post discharge plasma treatments in two low-pressure reactors, microwave and inductively coupled plasma. It is shown that the removal of various biomolecules, such as proteins, pyrogens or peptides, can be obtained at high rates and low temperatures in the inductively coupled plasma (ICP) by using Ar/O{sub 2} mixtures. Similar efficiency is obtained for bacterial spores. Analysis of the discharge conditions illustrates the role of ion bombardment associated with O radicals, leading to a fast etching of organic matter. By contrast, the conditions obtained in the post discharge lead to much lower etching rates but also to a chemical modification of pyrogens, leading to their de-activation. The advantages of the two processes are discussed for the application to the practical case of decontamination of medical devices and reduction of hospital infections, illustrating the advantages and drawbacks of the two approaches.

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

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

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

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

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

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)

Radiological survey following decontamination activities near the TA-45 site

International Nuclear Information System (INIS)

Gunderson, T.; Buhl, T.; Romero, R.; Salazar, J.

1983-07-01

Three areas at the site of a former radioactive liquid waste treatment plant at Los Alamos National Laboratory were decontaminated during 1982 by Bechtel Corporation, with health physics support provided by Eberline Instrument Corporation, under the Department of Energy's Formerly Utilized Sites Remedial Action Program (FUSRAP). Before decontamination, there were above-background concentrations of gross alpha, gross beta, 238 Pu, 239 240 Pu, 241 Am, 90 Sr, and 137 Cs in the surface soils. These combined concentrations were above operational decontamination guidelines for surface soil contamination. After cleanup operations, radionuclide concentrations in surface soils at all three sites were within decontamination guidelines

General recommendations for decontamination procedures to individuals

International Nuclear Information System (INIS)

Ohlenschlaeger, L.; Messerschmidt, J.P.

1989-04-01

The fundamental criteria in handling radioactive contaminated persons are discussed and methods of monitoring, including monitoring of contaminated wounds, as well as decontamination measures with reference to particularly exposed regions of the body are described. Each decontamination procedure has to be carried out cautiously and has to be stopped as soon as skin lesion would be ensured from too strong mechanical cleansing, in order to avoid any additional incorporation by an injured skin. As a rule, any residual radioactivity still adherent to the skin surface can be neglected as soon as avoidance of spreading of the contamination to surrounding areas is assured. Experience showed that contaminations with radioactive dust can be removed from the skin surface quite easily by such simple means like water and soap. Radioisotopes, however, as used in nuclear medicine, usually are having a higher adhesive effect to the skin surface, thus making conditions for decontamination more difficult. Measures related to the decontamination procedure such as monitoring, mode of sampling for bioassay in case of incidents, handling of waste resulting from decontamination, as well as self-protective aspects are discussed in the annex. (orig.) [de

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

Complexation studies of actinides (U, Pu, Am) with linear polyamino-carboxylate ligands and sidero-chelates; Etudes de la chelation d'actinides (U, Pu, Am) par des ligands polyaminocarboxylate lineaires et des siderochelates d'interet environnemental

Energy Technology Data Exchange (ETDEWEB)

Nguyen, L.V.

2010-11-25

As part of our research endeavour aimed at developing and improving decontamination processes of wastewater containing alpha emitters, physico-chemical complexation studies of actinides (U, Pu, Am) with organic open-chain ligands such as poly-aminocarboxylic acids (H{sub 4}EDTA) and sidero-chelates (di-hydroxamic acids and desferrioxamine B) have been carried out. Gaining a clear understanding of the coordination properties of the targeted actinides is an essential step towards the selection of the most appropriate chelating agents that will exhibit high uptake efficiencies. EXAFS (Extended X-ray Absorption Fine Structure) measurements at the ESRF synchrotron enabled to elucidate the coordination scheme of uranium and plutonium complexes. Solution thermodynamic investigations were intended to provide valuable information about the nature and the stability of the uranium(VI) and americium(III) complexes prevailing at a given pH in solution. The set of stability constants determined from potentiometric and UV-visible spectrophotometric titrations, allowed to predict the speciation of the selected actinides in presence of the aforementioned ligands and to determine the pH range required for achieving 'ultimate' decontamination. (author) [French] Dans le cadre du developpement et de l'amelioration des procedes de decontamination d'effluents aqueux contamines par des radioelements emetteurs alpha, des etudes physico-chimiques sur la complexation des actinides (U, Pu, Am) avec des ligands organiques tels que des acides polyaminocarboxyliques lineaires (H{sub 4}EDTA) et des siderochelates (acides dihydroxamiques et desferrioxamine B) ont ete effectuees. La comprehension des proprietes de coordination est une etape essentielle pour selectionner les meilleurs agents chelatants qui se montreront efficaces dans le traitement des effluents. Les schemas de coordination des complexes d'uranium et de plutonium avec ces ligands ont ete determines a l

Suspension, abandonment, decontamination, and surface land reclamation of upstream oil and gas facilities : informational letter IL 98-2

International Nuclear Information System (INIS)

1998-01-01

This release of the Alberta Energy and Utilities Board (EUB) is intended to clarify the jurisdictional roles of Alberta Environmental Protection (AEP) and the EUB with regard to their respective responsibilities for the regulation of the suspension, abandonment, decontamination and surface land reclamation of active and inactive upstream oil and gas facilities. The EUB, AEP and industrial operators all have separate roles and responsibilities when active and inactive upstream facilities are suspended or reclaimed. In the future, industry operators will have more interaction with the AEP during the decontamination of a site, while the EUB will concentrate on pollution prevention and abandonment of non-economic facilities. All oilfield waste generated from suspension, abandonment, decontamination, and surface land reclamation of an active or inactive upstream oil and gas facility will fall under the jurisdiction of the EUB. Contaminated soils, sludges, and waters that are physically removed as a result of decontamination activities are considered to be oilfield wastes. The regulatory responsibility between the AEP and the EUB remains unchanged for the reclamation process of on-lease and off-lease spills, releases or pipeline breaks. Industry operators are no longer allowed to discharge any produced liquid to earthen pits or ponds and are encouraged to reclaim existing ones. 3 figs

Decontamination of plutonium-contaminated surfaces

International Nuclear Information System (INIS)

Bertrand, J.; Clouet d'Orval, Ch.; Tachon, J.

1958-01-01

The measure of the neutron distribution in the core of 'Proserpine', by means of activation detectors, requires no contact between the plutonium sulfate solution and the detectors. These detectors are put into PVC or polyethylene bags. This report describes the process used to decontaminate these bags. A washing by nitric acid followed by coating with plexiglass is kept, with this process we have no contamination on the detectors. (author) [fr

Treatment and storage of contaminated materials; Traitement et stockage des materiels contamines

Energy Technology Data Exchange (ETDEWEB)

Cerre, P; Pomarola, J [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1959-07-01

The ultimate disposal of radioactive wastes sets an important problem which has been partly solved. France has temporarily adopted the following method: 1) Volume reduction, 2) Fixation of the activity in non leakable solids standing all temporarily or ultimate kinds of storing. According to those two basic principles the authors have presented: - a decontamination plant allowing maximum recovery of materials, - the plans of an installation devised for carrying out radioactive waste volume reduction and conditioning. Both of them are being built at Saclay. (author) [French] La destination finale des residus radioactifs pose un probleme imparfaitement resolu. La France a adopte, comme solution d'attente, le processus ci-dessous: 1) Reduction des volumes, 2) Confinement de l'activite dans des solides non lechables et pouvant resister a tous modes de stockage provisoire ou definitif. A partir des idees directrices, MM. CERRE et POMAROLA ont presente: - un batiment de decontamination permettant de recuperer le maximum de materiaux, - un projet d'installation visant a la reduction du volume des dechets radioactifs et leur conditionnement. Ces deux installations sont en cours d'execution a Saclay. (auteur)

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

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

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

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.)

Decontamination of titanium implant surface and re-osseointegration to treat peri-implantitis: a literature review

NARCIS (Netherlands)

Subramani, K.; Wismeijer, D.

2012-01-01

PURPOSE: To review the literature on decontamination of titanium implant surfaces following peri-implantitis and the effect of various cleaning methods on re-osseointegration. MATERIALS AND METHODS: An electronic search of the literature at PubMed was conducted on the studies published between 1966

MERCURY CONTAMINATED MATERIAL DECONTAMINATION METHODS: INVESTIGATION AND ASSESSMENT

Energy Technology Data Exchange (ETDEWEB)

M.A. Ebadian, Ph.D.

2001-01-01

Over the years mercury has been recognized as having serious impacts on human health and the environment. This recognition has led to numerous studies that deal with the properties of various mercury forms, the development of methods to quantify and speciate the forms, fate and transport, toxicology studies, and the development of site remediation and decontamination technologies. This report reviews several critical areas that will be used in developing technologies for cleaning mercury from mercury-contaminated surfaces of metals and porous materials found in many DOE facilities. The technologies used for decontamination of water and mixed wastes (solid) are specifically discussed. Many technologies that have recently appeared in the literature are included in the report. Current surface decontamination processes have been reviewed, and the limitations of these technologies for mercury decontamination are discussed. Based on the currently available technologies and the processes published recently in the literature, several processes, including strippable coatings, chemical cleaning with iodine/iodide lixiviant, chemisorbing surface wipes with forager sponge and grafted cotton, and surface/pore fixation through amalgamation or stabilization, have been identified as potential techniques for decontamination of mercury-contaminated metal and porous surfaces. Their potential merits and applicability are discussed. Finally, two processes, strippable coatings and chemical cleaning with iodine/iodide lixiviant, were experimentally investigated in Phase II of this project.

Decontamination of U-metal surface by an oxidation etching system

Energy Technology Data Exchange (ETDEWEB)

Stout, R.B.; Kansa, E.J.; Shaffer, R.J.; Weed, H.C. [California Univ., Livermore, CA (United States). Lawrence Livermore National Lab

2001-07-01

A surface treatment to remove surface contamination from uranium (U) metal and/or hydrides of uranium and heavy metals (HM) from U-metal parts is described. In the case of heavy metal atomic contamination on a surface, and potentially several atomic layers beneath, the surface oxidation treatment combines both chemical and chemically driven mechanical processes. The chemical process is a controlled temperature-time oxidation process to create a thin film of uranium oxide (UO{sub 2} and higher oxides) on the U-metal surface. The chemically driven mechanical process is strain induced by the volume increase as the U-metal surface transforms to a UO{sub 2} surface film. These volume strains are significantly large to cause surface failure spalling/scale formation and thus, removal of a U-oxide film that contains the HM-contaminated surface. The case of a HM-hydride surface contamination layer can be treated similarly by using inert hot gas to decompose the U-hydrides and/or HM-hydrides that are contiguous with the surface. A preliminary analysis to design and to plan for a sequence of tests is developed. The tests will provide necessary and sufficient data to evaluate the effective implementation and operational characteristics of a safe and reliable system. The following description is limited to only a surface oxidation process for HM-decontamination. (authors)

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

OpenAIRE

MILAN S. TRTICA; SCEPAN S. MILJANIC; NATASA N. STJEPANOVIC

2000-01-01

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 lase...

Mécanismes d'écoulement des charges à la surface des polymères granulaires

Directory of Open Access Journals (Sweden)

M. Kachi

2014-09-01

Full Text Available Les forces électriques s’exerçant sur des polymères granulaires chargés sont mises à profit dans plusieurs processus électrostatiques. La dynamique de charges de surface de ces matériaux est très importante pour ce type de processus. Le but de ce papier est d’analyser l’écoulement des charges à la surface de couches compactes de polymères granulaires, en interprétant les mesures sans contact réalisées par trois sondes de potentiel, de champ et de charge, ayant chacune une taille différente. Des mesures du profile de potentiel à différents instants sont également réalisées afin d’expliquer les différences entre les vitesses de déclin de potentiel, de champ et de charge mesurées par les trois sondes. Les résultats mettent en évidence un écoulement transversal et longitudinal de la charge surfacique.

Growth of micrometric oxide layers to explore laser decontamination of metallic surfaces

OpenAIRE

Carvalho Luisa; Pacquentin Wilfried; Tabarant Michel; Maskrot Hicham; Semerok Alexandre

2017-01-01

The nuclear industry produces a wide range of radioactive waste in terms of hazard level, contaminants and material. For metallic equipment like steam generators, the radioactivity is mainly located in the oxide surface. In order to study and develop safe techniques for dismantling and for decontamination, it is important to have access to oxide layers with a representative distribution of non-radioactive contaminants. In this paper we propose a method for the creation of oxide layers on stai...

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.)

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

Organization of work for prevention of propagation of radioactive contamination, for decontamination of the premise surfaces and individual protective means in case of radiation accident

International Nuclear Information System (INIS)

Klochkov, V.N.; Vas'kin, A.G.; Filatova, V.M.

1995-01-01

Radiation accident results in radioactive contamination of the surface, clothes and other property. If proper measures are taken, it will prevent propagation of contamination. Decontamination of surfaces - is a complicated and tedious process. The paper has examined the measures of organization and technical aspects of prevention of propagation of radioactive contamination. Methods of decontamination of internal surfaces of premises are demonstrated, organization of the individual protective means is determined. 9 refs

Strippable core-shell polymer emulsion for decontamination of radioactive surface contamination

International Nuclear Information System (INIS)

Hwang, Ho-Sang; Seo, Bum-Kyoung; Lee, Kune-Woo

2011-01-01

In this study, the core-shell composite polymer for decontamination from the surface contamination was synthesized by the method of emulsion polymerization and blends of polymers. The strippable polymer emulsion is composed of the poly(styrene-ethyl acrylate) [poly(St-EA)] composite polymer, poly(vinyl alcohol) (PVA) and polyvinylpyrrolidone (PVP). The morphology of the poly(St-EA) composite emulsion particle was core-shell structure, with polystyrene (PS) as the core and poly(ethyl acrylate) (PEA) as the shell. Core-shell polymers of styrene (St)/ethyl acrylate (EA) pair were prepared by sequential emulsion polymerization in the presence of sodium dodecyl sulfate (SDS) as an emulsifier using ammonium persulfate (APS) as an initiator. Related tests and analysis confirmed the success in synthesis of composite polymer. The products are characterized by FT-IR spectroscopy, TGA that were used, respectively, to show the structure, the thermal stability of the prepared polymer. Two-phase particles with a core-shell structure were obtained in experiments where the estimated glass transition temperature and the morphologies of emulsion particles. Decontamination factors of the strippable polymeric emulsion were evaluated with the polymer blend contents. (author)

Experiences with decontaminating tritium-handling apparatus

International Nuclear Information System (INIS)

Maienschein, J.L.; Garcia, F.; Garza, R.G.; Kanna, R.L.; Mayhugh, S.R.; Taylor, D.T.

1991-07-01

Tritium-handling apparatus has been decontaminated as part of the shutdown of the LLNL Tritium Facility. Two stainless-steel gloveboxes that had been used to process lithium deuteride-tritide (LiDT) salt were decontaminated using the Portable Cleanup System so that they could be flushed with room air through the facility ventilation system. Further surface decontamination was performed by scrubbing the interior with paper towels and ethyl alcohol or Swish trademark. The surface contamination, as shown by swipe surveys, was reduced from 4x10 4 --10 6 disintegrations per minute (dpm)/cm 2 to 2x10 2 --4x10 4 dpm/cm 2 . Details on the decontamination operation are provided. A series of metal (palladium and vanadium) hydride storage beds have been drained of tritium and flushed with deuterium in order to remove as much tritium as possible. The bed draining and flushing procedure is described, and a calculational method is presented which allows estimation of the tritium remaining in a bed after it has been drained and flushed. Data on specific bed draining and flushing are given

Development of remote control decontamination machines for BWR nuclear power plants

International Nuclear Information System (INIS)

Miyakawa, Minoru; Nozawa, Katsuro; Yamada, Masuji; Mizutani, Takeshi; Onozuka, Kazuaki

1981-01-01

The dose rate of radiation on the surfaces of equipments and in rooms tends to increase as radioactive substances accumulate with the continuous operation of nuclear power stations. The decontamination works to remove radioactive substances are carried out to prevent the exposure of workers in the case of inspection and repair. In order to reduce the exposure of decontamination workers, to save labor and to shorten decontamination time, Chubu Electric Power Co., Inc., has developed the decontamination machines for the walls of reactor wells, the walls and bottoms of equipment pits, the internal surfaces of suppression chambers, and the internal surfaces of tanks. The decontamination machines have several remote-handling functions: (a) brushing up with sprinkling against complicate surface such as a wall with step, (b) vertical transfer of brushing position with sucking force, (c) sucking out slurries under the water of storage pool or inside the pressure-supression pool, (d) horizontal transfer of suction position with electric motors. (J.P.N.)

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)

Decision Analysis System for Selection of Appropriate Decontamination Technologies

International Nuclear Information System (INIS)

Ebadian, M.A.; Boudreaux, J.F.; Chinta, S.; Zanakis, S.H.

1998-01-01

The principal objective for designing Decision Analysis System for Decontamination (DASD) is to support DOE-EM's endeavor to employ the most efficient and effective technologies for treating radiologically contaminated surfaces while minimizing personnel and environmental risks. DASD will provide a tool for environmental decision makers to improve the quality, consistency, and efficacy of their technology selection decisions. The system will facilitate methodical comparisons between innovative and baseline decontamination technologies and aid in identifying the most suitable technologies for performing surface decontamination at DOE environmental restoration sites

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)

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

Decontamination effects of a simulated contaminated floor surface by a teleoperated mopping system

International Nuclear Information System (INIS)

Kim, Ki Ho; Kwon, Hyok Jo; Park, Jang Jin; Yang, Myung Seung

2004-01-01

A Tele Operated Mopping System (TOMS) was developed for use in the radioactive zone of the M6 hot-cell of the Irradiated Material Examination Facility (IMEF) at the Korea Atomic Energy Research Institute (KAERI). TOMS was designed to remove contaminated dry particulates, dust, and smears existing on the floor surface of the M6 hot-cell by mopping it in a remote manner. TOMS has three subsystems - a mobile mopping slave located inside the hot-cell, and a mopping master and a control console located outside the hot-cell. The mobile mopping slave consists of a tracked mobile platform, a mopping tool, and a wet mopping cloth, which were constructed in modules to facilitate a maintenance. This paper aims at describing the mopping capability of the developed TOMS - decontamination capability. In this work the decontamination capability is defined by the ratio of the removed contaminated area when the mopping cloth was passed over. The experiment was carried out by varying the speeds of the mopping slave and the roller, while the mopping force driven by the operator was constant. The roller of the mopping tool mounted on the mopping slave was designed to collect the mopping cloth used. The experimental results showed that the speeds of the mopping slave and the roller influence the extent of the decontamination

MERCURY CONTAMINATED MATERIAL DECONTAMINATION METHODS: INVESTIGATION AND ASSESSMENT; TOPICAL

International Nuclear Information System (INIS)

M.A. Ebadian, Ph.D.

2001-01-01

Over the years mercury has been recognized as having serious impacts on human health and the environment. This recognition has led to numerous studies that deal with the properties of various mercury forms, the development of methods to quantify and speciate the forms, fate and transport, toxicology studies, and the development of site remediation and decontamination technologies. This report reviews several critical areas that will be used in developing technologies for cleaning mercury from mercury-contaminated surfaces of metals and porous materials found in many DOE facilities. The technologies used for decontamination of water and mixed wastes (solid) are specifically discussed. Many technologies that have recently appeared in the literature are included in the report. Current surface decontamination processes have been reviewed, and the limitations of these technologies for mercury decontamination are discussed. Based on the currently available technologies and the processes published recently in the literature, several processes, including strippable coatings, chemical cleaning with iodine/iodide lixiviant, chemisorbing surface wipes with forager sponge and grafted cotton, and surface/pore fixation through amalgamation or stabilization, have been identified as potential techniques for decontamination of mercury-contaminated metal and porous surfaces. Their potential merits and applicability are discussed. Finally, two processes, strippable coatings and chemical cleaning with iodine/iodide lixiviant, were experimentally investigated in Phase II of this project

40 CFR 761.378 - Decontamination, reuse, and disposal of solvents, cleaners, and equipment.

Science.gov (United States)

2010-07-01

... of solvents, cleaners, and equipment. 761.378 Section 761.378 Protection of Environment ENVIRONMENTAL...-Porous Surfaces § 761.378 Decontamination, reuse, and disposal of solvents, cleaners, and equipment. (a) Decontamination. Decontaminate solvents and non-porous surfaces on equipment in accordance with the standards and...

Chemical and mechanical decontamination processes to minimize secondary waste decommissioning

International Nuclear Information System (INIS)

Enda, M.; Ichikawa, N.; Yaita, Y.; Kanasaki, T.; Sakai, H.

2008-01-01

In the decommissioning of commercial nuclear reactors in Japan, prior to the dismantling of the nuclear power plants, there are plans to use chemical techniques to decontaminate reactor pressure vessels (RPVs), internal parts, primary loop recirculation systems (PLRs), reactor water clean up systems (RWCUs), etc., so as to minimize radiation sources in the materials to be disposed of. After dismantling the nuclear power plants, chemical and mechanical decontamination techniques will then be used to reduce the amounts of radioactive metallic waste. Toshiba Corporation has developed pre-dismantling and post-dismantling decontamination systems. In order to minimize the amounts of secondary waste, the T-OZON process was chosen for decontamination prior to the dismantling of nuclear power plants. Dismantling a nuclear power plant results in large amounts of metallic waste requiring decontamination; for example, about 20,000 tons of such waste is expected to result from the dismantling of a 110 MWe Boiling Water Reactor (BWR). Various decontamination methods have been used on metallic wastes in preparation for disposal in consideration of the complexity of the shapes of the parts and the type of material. The materials in such nuclear power plants are primarily stainless steel and carbon steel. For stainless steel parts having simple shapes, such as plates and pipes, major sources of radioactivity can be removed from the surface of the parts by bipolar electrolysis (electrolyte: H 2 SO 4 ). For stainless steel parts having complicated shapes, such as valves and pumps, major sources of radioactivity can be removed from the surfaces by redox chemical decontamination treatments (chemical agent: Ce(IV)). For carbon steel parts having simple shapes, decontamination by blasting with zirconia grit is effective in removing major sources of radioactivity at the surface, whereas for carbon steel parts having complicated shapes, major sources of radioactivity can be removed from

Volume reduction and material recirculation by freon decontamination

International Nuclear Information System (INIS)

Berners, O.; Buhmann, D.; Yamashita, Y.; Yoshiaki, M.

1989-01-01

This paper discusses the use of freon in a large variety of decontamination in the nuclear and non-nuclear fields. As far as the contamination is loose or smerable, surfaces of nearly all materials can be decontaminated. Freon is electrically non-conductive, chemically neutral and has a low surface tension. So it is capable of creeping under the contaminant and loosening or dissolving it. Used freon can be collected, cleaned and recirculated. Its cleaning can be done easily by evaporation at its lower vapor point of about 48 degrees C (104 degrees F). Good decontamination results could be achieved, expensive materials, tools and equipment could be recirculated. Big volumes of materials could get separated from their contaminants, which is the real radioactive waste. Freon decontamination is an effective, overall economical and approved technology to volume reduction and material recirculation

Plasma decontamination of uranium oxide from stainless steel surfaces

International Nuclear Information System (INIS)

Veilleux, J.M.; El-Genk, M.S.; Chamberlin, E.P.

1997-01-01

The U.S. Department of Energy (DOE) is expected to have 845000 m 3 of transuranic (TRU) waste by the year 2000 that has accumulated during the development and assembly of the nation's nuclear stockpile. The TRU disposal costs alone range up to $28000/m 3 , which could be reduced to $1800/m 3 or less by treating and converting the material to low-level waste. Plasma-based processes have been shown to remove plutonium and uranium surface contaminants from metallic components and could be used to treat TRU with significant cost avoidance, estimated at over $1.0 billion. Martz and Hess conducted the initial work of plutonium etching in low-power radio-frequency (rf) plasma with etch rates ranging from 0.007 to 0.025 kg/m 2 ·h. Veilleux et al. reported that plasma decontamination of uranium from the interior of aluminum objects results in etch rates an order of magnitude greater. The current work reports on removal rates of uranium from stainless steel surfaces and includes estimates of the etch rates and characteristic times for removal

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

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.)

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)

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)

Cold plasma decontamination using flexible jet arrays

Science.gov (United States)

Konesky, Gregory

2010-04-01

Arrays of atmospheric discharge cold plasma jets have been used to decontaminate surfaces of a wide range of microorganisms quickly, yet not damage that surface. Its effectiveness in decomposing simulated chemical warfare agents has also been demonstrated, and may also find use in assisting in the cleanup of radiological weapons. Large area jet arrays, with short dwell times, are necessary for practical applications. Realistic situations will also require jet arrays that are flexible to adapt to contoured or irregular surfaces. Various large area jet array prototypes, both planar and flexible, are described, as is the application to atmospheric decontamination.

Los Alamos DP West Plutonium Facility decontamination project

International Nuclear Information System (INIS)

Garde, R.; Cox, E.J.; Valentine, A.M.

1982-01-01

The DP West Plutonium Facility operated by the Los Alamos National Laboratory, Los Alamos, New Mexico, was decontaminated between April 1978 and April 1981. The facility was constructed in 1944 to 1945 to produce plutonium metal and fabricate parts for nuclear weapons. It was continually used as a plutonium processing and research facility until mid-1978. Decontamination operations included dismantling and removing gloveboxes and conveyor tunnels; removing process systems, utilities, and exhaust ducts; and decontaminating all remaining surfaces. This report describes glovebox and conveyor tunnel separations, decontamination techniques, health and safety considerations, waste management procedures, and costs of the operation

Improvement in ultraviolet based decontamination rate using meta-materials

Science.gov (United States)

Enaki, Nicolae A.; Bazgan, Sergiu; Ciobanu, Nellu; Turcan, Marina; Paslari, Tatiana; Ristoscu, Carmen; Vaseashta, Ashok; Mihailescu, Ion N.

2017-09-01

We propose a method of decontamination using photon-crystals consisting of microspheres and fiber optics structures with various geometries. The efficient decontamination using the surface of the evanescent zone of meta-materials opens a new perspective in the decontamination procedures. We propose different topological structures of meta-materials to increase the contact surface of UV radiation with contaminated liquid. Recent observation of the trapping of dielectric particles along the fibers help us propose a new perspective on the new possibilities to trap the viruses, bacteria and other microorganisms from liquids, in this special zone, where the effective UV coherent Raman decontamination becomes possible. The nonlinear theory of the excitation of vibration modes of bio-molecule of viruses and bacteria is revised, taking into consideration the bimodal coherent states in coherent Raman excitation of biomolecules.

Comparison of Selected Methods for Individual Decontamination of Chemical Warfare Agents

Directory of Open Access Journals (Sweden)

Tomas Capoun

2014-06-01

Full Text Available This study addresses the individual decontamination of chemical warfare agents (CWA and other hazardous substances. The individual decontamination applies to contaminated body surfaces, protective clothing and objects immediately after contamination, performed individually or by mutual assistance using prescribed or improvised devices. The article evaluates the importance of individual decontamination, security level for Fire and Rescue Service Units of the Czech Republic (FRS CR and demonstrates some of the devices. The decontamination efficiency of selected methods (sorbent, glove and sponge, two-chamber foam device and wiping with alcohol was evaluated for protective clothing and painted steel plate contaminated with O-ethyl-S-(diisopropylaminoethyl-methylthiophosphonate (VX, sulfur mustard, o-cresol and acrylonitrile. The methods were assessed from an economic point of view and with regard to specific user parameters, such as the decontamination of surfaces or materials with poor accessibility and vertical surfaces, the need for a water rinse as well as toxic waste and its disposal.

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)

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

Electrolytic decontamination of conductive materials for hazardous waste management

International Nuclear Information System (INIS)

Wedman, D.E.; Martinez, H.E.; Nelson, T.O.

1996-01-01

Electrolytic removal of plutonium and americium from stainless steel and uranium surfaces has been demonstrated. Preliminary experiments were performed on the electrochemically based decontamination of type 304L stainless steel in sodium nitrate solutions to better understand the metal removal effects of varying cur-rent density, pH, and nitrate concentration parameters. Material removal rates and changes in surface morphology under these varying conditions are reported. Experimental results indicate that an electropolishing step before contamination removes surface roughness, thereby simplifying later electrolytic decontamination. Sodium nitrate based electrolytic decontamination produced the most uniform stripping of material at low to intermediate pH and at sodium nitrate concentrations of 200 g L -1 and higher. Stirring was also observed to increase the uniformity of the stripping process

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

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

Preliminary findings of the effect of surface finish and coatings on PuO2 contamination hold-up and ease of decontamination in aqueous and non-aqueous media

International Nuclear Information System (INIS)

Dalton, J.T.; Chamberlain, H.E.; Turner, A.D.; Dawson, R.K.

1984-11-01

The application of temporary and permanent coatings for the reduction of α-activity hold-up and increased ease of decontamination has been reviewed and a variety of surface treatments and coatings identified as being worthy of investigation. A range of specimens have been prepared with hard coatings and smooth surfaces. A number of adhesive films, paints and lacquers have been applied to mild and stainless steel substrates. In order to compare the different surfaces, a standard contamination technique using a mechanical wiper has been developed to reproducibly contaminate the materials with PuO 2 . A standard decontamination test using water/Decon 75 or Arklone X is being used to compare the ease of decontamination. Preliminary experiments have shown that the smoothest surface finishes have the lowest activity hold-up and are more easily cleaned. Due to the superior level of micro-smoothness attainable on metals, these showed a significantly lower activity retention than the organic coatings examined to date. A comparison of the relative efficiency of cleaning in Decon 75 and Arklone X showed that generally speaking metal surfaces were cleaned equally well by both media, while the unaged organic surfaces were decontaminated more thoroughly in Arklone X, though the differences were somewhat marginal. (author)

The treatment of effluents; Ameliorations apportees aux traitements des residus radioactifs

Energy Technology Data Exchange (ETDEWEB)

Wormser, G; Rodier, J; Robien, E de; Fernandez, N [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1964-07-01

resins are used in the sodium form; the regeneration is carried out using a sodium salt solution which, after decontamination by coprecipitation is used again. With this process it is possible to use a smaller volume of sludge. 2 - The use of a natural evaporator. This process uses atmospheric air which is not saturated with water vapour and which is at a normal temperature, in order to extract water from the aqueous effluents. (authors) [French] Depuis plusieurs annees, le Commissariat a l'Eneregie Atomique Francais s'est penche avec interet sur les problemes poses par les effluents radioactifs. Les hautes activites n'ayant pas encore recu de solution definitive, nous nous bornerons a traiter, dans cette communication, que des realisations et des recherches relatives aux effluents faiblement et moyennement actifs. Dans le domaine des realisations, diverses stations de traitement ont ete construites en France; nous en ferons une breve enumeration, tout en faisant ressortir les nouveautes les plus importantes. C'est ainsi que nous presenterons plus specialement les dernieres stations de traitement mises en oeuvre (Grenoble, Fontenay-aux-Roses, Cadarache). De I'ensemble de ces realisations nouvelles, nous traiterons d'une maniere un peu plus approfondie, les trois sujets suivants: 1 - Atelier de conditionnement par bitumage des boues provenant de la concentration des radio-nucleides. 2 - Atelier de traitement des dechets solides radioactifs et combustibles par incineration. 3 - Ensemble de concentration effluents liquides radioactifs par evaporation. Dans le domaine de la recherche, de nombreuses voies ont ete abordees; nous en ferons I'inventaire. Il s'agit, dans la plupart des cas, de la concentration des radio-nucleides en vue d'un stockage pratique et peu onereux, concentration associee a une decontamination efficace, et Ie meilleur marche possible, des liquides aqueux, en vue de leur rejet. Pour l'amelioration des traitements aboutissant a la concentration des radio

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

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

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.

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

DNA decontamination methods for internal quality management in clinical PCR laboratories.

Science.gov (United States)

Wu, Yingping; Wu, Jianyong; Zhang, Zhihui; Cheng, Chen

2018-03-01

The polymerase chain reaction (PCR) technique, one of the most commonly applied methods in diagnostic and molecular biology, has a frustrating downside: the occurrence of false-positive signals due to contamination. In previous research, various DNA decontamination methods have been developed to overcome this limitation. Unfortunately, the use of random or poorly focused sampling methods for monitoring air and/or object surfaces leads to the incomplete elimination during decontamination procedures. We herein attempted to develop a novel DNA decontamination method (environmental surveillance, including surface and air sampling) and quality management program for clinical molecular diagnostic laboratories (or clinical PCR laboratories). Here, we performed a step-by-step evaluation of current DNA decontamination methods and developed an effective procedure for assessing the presence of decontaminating DNA via PCR analysis. Performing targeted environmental surveillance by sampling, which reached optimal performance over 2 weeks, and the decontamination process had been verified as reliable. Additionally, the process was validated to not affect PCR amplification efficiency based on a comparative study. In this study, effective guidelines for DNA decontamination were developed. The method employed ensured that surface DNA contamination could be effectively identified and eliminated. Furthermore, our study highlighted the importance of overall quality assurance and good clinical laboratory practices for preventing contamination, which are key factors for compliance with regulatory or accreditation requirements. Taken together, we provided the evidence that the presented scheme ranged from troubleshooting to the elimination of surface contamination, could serve as critical foundation for developing regular environmental surveillance guidelines for PCR laboratories. © 2017 Wiley Periodicals, Inc.

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)

Spécification géométrique des produits (GPS) -- Indication des états de surface dans la documentation technique de produits

CERN Document Server

International Organization for Standardization. Geneva

2002-01-01

La présente Norme internationale spécifie les règles pour l'indication des états de surface dans la documentation technique de produits (par exemple dessins, spécifications, contrats, rapports) au moyen de symboles graphiques et d'indications textuelles. Elle est applicable à l'indication des exigences sur les surfaces au moyen de paramètres de profil conformément à l'ISO 4287, relatifs au profil R (paramètres de rugosité), au profil W (paramètres d'ondulation) et au profil P (paramètres de structure), de paramètres liés aux motifs conformément à l'ISO 12085, relatifs au motif de rugosité et au motif d'ondulation, et de paramètres relatifs à la courbe du taux de longueur portante conformément à l'ISO 13565-2 et à l'ISO 13565-3. NOTE Quant à l'indication des exigences concernant les imperfections de surface (pores, stries, etc.), qui ne peuvent pas être spécifiées à l'aide des paramètres d'état de surface, référence est faite à l'ISO 8785 qui couvre les imperfections de surface...

Soil removal as a decontamination practice and radiocesium accumulation in tadpoles in rice paddies at Fukushima

International Nuclear Information System (INIS)

Sakai, Masaru; Gomi, Takashi; Nunokawa, Masanori; Wakahara, Taeko; Onda, Yuichi

2014-01-01

We investigated the biological accumulation of radiocesium in tadpoles [Rana (Pelophylax) porosa porosa] in rice paddies with and without decontamination practice at Fukushima. Radiocesium was accumulated in surface part of soils both in the control and decontaminated paddies one year after decontamination. Mean 134 Cs and 137 Cs concentrations in tadpoles in the control and decontaminated paddies were 3000 and 4500, and 600 and 890 Bq/kg dry weight, respectively. Radiocesium concentrations in surface soil (0–5 cm depth) and tadpoles in the decontaminated paddy were five times smaller than in the control paddy. These results suggest that decontamination practice can reduce radiocesium concentrations in both soil and tadpoles. However, at the decontaminated paddy, radiocesium concentrations in surface soils became 3.8 times greater one year after decontamination, which indicates that monitoring the subsequent movement of radiocesium in rice paddies and surrounding areas is essential for examining contamination propagation. - Highlights: • Surface soil removal in a rice paddy reduced the radiocesium concentration in soil. • The radiocesium concentration in tadpoles decreased following decontamination. • Radiocesium levels in soil increased at 1 year following decontamination practice. • Reduction of radiocesium of soil can propagate to biota in rice paddies. - Decontamination practice reduced radiocesium concentrations in both soil and tadpoles that suggests reduction of radiocesium of soil can propagate to biota in rice paddies

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.

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)

Effectiveness of disinfectant wipes for decontamination of bacteria on patients' environmental and medical equipment surfaces at Siriraj Hospital.

Science.gov (United States)

Seenama, Chakkraphong; Tachasirinugune, Peenithi; Jintanothaitavorn, Duangporn; Kachintorn, Kanchana; Thamlikitkul, Visanu

2013-02-01

To determine the effectiveness of Virusolve+ disinfectant wipes and PAL disinfectant wipes for decontamination of inoculated bacteria on patients' environmental and medical equipment surfaces at Siriraj Hospital. Tryptic soy broths containing MRSA and XDR A. baumannii were painted onto the surfaces of patient's stainless steel bed rail, patient's fiber footboard, control panel of infusion pump machine and control panel of respirator. The contaminated surfaces were cleaned by either tap water, tap water containing detergent, Virusolve+ disinfectant wipes or PAL disinfectant wipes. The surfaces without any cleaning procedures served as the control surface. The contaminated surfaces cleaned with the aforementioned procedures and control surfaces were swabbed with cotton swabs. The swabs were streaked on agar plates to determine the presence of MRSA and XDR A. baumannii. MRSA and XDR A. baumannii were recovered from all control surfaces. All surfaces cleaned with tap water or tap water containing detergent revealed presence of both MRSA and XDR A. baumannii. However the amounts of bacteria on the surfaces cleaned with tap water containing detergent were less than those cleaned with tap water alone. All surfaces cleaned with PAL disinfectant wipes also revealed presence of both MRSA and XDR A. baumannii. However the amounts of bacteria on the surfaces cleaned with PAL disinfectant wipes were less than those cleaned with tap water containing detergent. No bacteria were recovered from all surfaces cleaned with Virusolve+ disinfectant wipes. Virusolve+ disinfectant wipes were more effective than tap water; tap water containing detergent and PAL disinfectant wipes for decontamination of bacteria inoculated on patients environmental and medical equipment surfaces at Siriraj Hospital.

Equipment for decontamination of inner vessel surfaces featuring sound or ultrasound transducer on float inside liquid-filled vessel

International Nuclear Information System (INIS)

Bar, J.; Straka, M.

1982-01-01

The equipment for the decontamination of the inner surfaces of vessels consists of an immersion float which is provided with a screw, an electric motor, a rudder and at least one float chamber, and a remotely controlled valve. The float is provided with a power source, a high frequency a.c. current generator and a control panel outside the vessel. The float is connected to parts of the equipment outside the vessel by a multi-core cable. The immersion float may also be provided with a detector for measuring the quantity of ionizing radiation whose display is placed outside the vessel being decontaminated. (B.S.)

The efficacy of surface active substances to decontaminate radioactive pollution of animals

International Nuclear Information System (INIS)

Kossakowski, S.

1975-01-01

The purpose of the work was to determine the efficacy of native surface-active substances in the decontamination of pig pollution with 90 Sr, 131 J, 144 Ce and 137 Cs. The appraisal was performed on the basis of indices of final activity. It was found that an Ixi solution was the most efficient against 137 Cs, E powder and Kokosal against 144 Ce and 90 Sr respectively, and also E powder against 137 J. The most universal proved to be enzymatic powders E and R, and then the detergens Ixi, Bis, FF and Kokosal. (author)

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

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

Study of various decontamination processes for evaporation concentrates; Etude de differents traitements de decontamination sur des concentrats d'evaporation

Energy Technology Data Exchange (ETDEWEB)

Lefillatre, G; Cudel, Y; Rodi, L [Commissariat a l' Energie Atomique, Chusclan (France). Centre de Production de Plutonium de Marcoule

1968-07-01

insolubiliser les radioelements contenus dans les concentrats avant leur enrobage eventuel par le bitume. Dans ce but, la fixation sur des produits mineraux, la precipitation sous forme de sels insolubles ou l'adsorption sur des coprecipites ont ete envisagees. Dans le cas de la fixation des radioelements par des produits mineraux d'origine naturelle ou synthetique a pouvoir absorbant eleve tels que: argiles, diatomees, silicates synthetiques et alumines, 48 produits ont ete experimentes. Leur efficacite selective vis-a-vis du {sup 137}Cs - {sup 90}Sr - {sup 106}Ru-Rh - {sup 144}Ce-Pr - {sup 95}Zr-Nb a ete determinee d'une part sur des concentrats acides, d'autre part sur des concentrate neutralises (precipitation des hydroxydes). Dans le cas de la fixation des radioelements a l'etat de sels insolubles ou de leur adsorption sur des coprecipites, le choix des traitements a porte sur les 2 radioelements les plus dangereux: {sup 137}Cs - {sup 90}Sr. Les traitements classiques ont ete experimentes. Pour le {sup 90}Sr: carbonate de calcium, oxalate de calcium, phosphate de calcium, phosphate de strontium, oxydes de manganese, sulfate de baryum. Pour le {sup 137}Cs: les ferrocyanures de nickel, de cuivre, de zinc, de cobalt, de manganese. La technique a consiste a effectuer les precipitations (hydroxydes, traitements specifiques du {sup 90}Sr et {sup 137}Cs) les unes a la suite des autres sans separer les precipites. (auteurs)

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

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

Soil removal as a decontamination practice and radiocesium accumulation in tadpoles in rice paddies at Fukushima.

Science.gov (United States)

Sakai, Masaru; Gomi, Takashi; Nunokawa, Masanori; Wakahara, Taeko; Onda, Yuichi

2014-04-01

We investigated the biological accumulation of radiocesium in tadpoles [Rana (Pelophylax) porosa porosa] in rice paddies with and without decontamination practice at Fukushima. Radiocesium was accumulated in surface part of soils both in the control and decontaminated paddies one year after decontamination. Mean (134)Cs and (137)Cs concentrations in tadpoles in the control and decontaminated paddies were 3000 and 4500, and 600 and 890 Bq/kg dry weight, respectively. Radiocesium concentrations in surface soil (0-5 cm depth) and tadpoles in the decontaminated paddy were five times smaller than in the control paddy. These results suggest that decontamination practice can reduce radiocesium concentrations in both soil and tadpoles. However, at the decontaminated paddy, radiocesium concentrations in surface soils became 3.8 times greater one year after decontamination, which indicates that monitoring the subsequent movement of radiocesium in rice paddies and surrounding areas is essential for examining contamination propagation. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

A Study on Decontamination Process Using Atmospheric Pressure Plasma

International Nuclear Information System (INIS)

Kim, Yong Soo; Jeon, Sang Hwan; Jin, Dong Sik; Park, Dong Min

2010-05-01

Radioactive decontamination process using atmospheric pressure plasma which can be operated parallel with low vacuum cold plasma processing is studied. Two types of cold plasma torches were designed and manufactured. One of them is the cylindrical type applicable to the treatment of three-dimensional surfaces. The other is the rectangular type for the treatment of flat and large surface areas. Ar palsam was unstable but using He as a carrier gas, discharge condition was improved. Besides filtering module using pre, medium, charcoal, and HEPA filter was designed and manufactured. More intensive study for developing filtering system will be followed. Atmospheric pressure plasma decontamination process can be used to the equipment and facility wall decontamination

Growth of micrometric oxide layers for the study of metallic surfaces decontamination by laser

OpenAIRE

Carvalho Luisa; Pacquentin Wilfried; Tabarant Michel; Maskrot Hicham; Semerok Alexandre

2017-01-01

The nuclear industry produces a wide range of radioactive waste in term of level of hazard, contaminants and material. For metallic equipment like steam generators, the radioactivity is mainly located in the oxide surface. In order to study and develop techniques for dismantling and for decontamination in a safe way, it is important to have access to oxide layers with a representative distribution of non-radioactive contaminants. We propose a method of formation of oxide layer on stainless st...

Decontamination process development for gravels contaminated with uranium

Energy Technology Data Exchange (ETDEWEB)

Kim, Gye Nam; Park, Uk Ryang; Kim, Seung Su; Kim, Won Suk; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2013-10-15

It is impossible to scrub gravels in a washing tank, because gravels sinks to the bottom of the washing tank. In addition, when electrokinetic decontamination technology is applied to gravels larger than 10 cm, the removal efficiency of uranium from the gravels is reduced, because electro-osmotic flux at the surface of the gravel in electrokinetic cell reduces owing to a reduction of the particle surface area attributable to large-sized gravel. The volume ratio of gravel larger than10 cm in total volume of the soil in KAERI was about 20%. Therefore, it is necessary to study the decontamination process of gravels contaminated with radionuclides. The optimum number of washings for contaminated gravels is considered to be two. In addition, the removal efficiency of contaminated gravel was not related to its weight. For an electrokinetic-electrodialytic decontamination period of 5 days, 10 days, 15 days, and 20 days, {sup 238}U in gravel was removed by about 42%, 64%, 74%, and 80%, respectively. The more the decontamination time elapsed, the greater the reduction of the removal efficiency ratio of {sup 238}U. The decontamination process for gravels was generated on the basis of the results of washing and electrokinetic electrodialtic experiments.

Development of decontamination system for radioactive matter on paved road using dry ice blast method

International Nuclear Information System (INIS)

Nagamine, Haruo; Wakayama, Masanori; Nakamura, Hiroshi

2014-01-01

As a decontamination method for paved road surface, the 'Dry Ice Blast Decontamination System' has been developed. This decontamination system has characteristic as follows; 1) Generation of decontamination waste is extremely small, 2) not using water, 3) not damaging the pavement surface. In actual decontamination work, more than 60% average (maximum 84%) reduction rate of the radiation counting rate has been achieved. In addition to these features, this system prevent the diffusion into the surrounding and the radiation exposure of workers by sucking waste quickly using attached dust collecting function. This system is also characterized in that it does not cause a difference in skill by the operator because of faceted decontamination using repetitive motion by concatenating three pellet injection nozzle and self-propelled decontamination machine. (author)

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

Dry Ice Blast Decontamination to in-service equipment in Japanese PWR plant

International Nuclear Information System (INIS)

2016-01-01

MHI had developed several mechanical decontamination methods. Mechanical decontamination is beneficial when it is applied to equipment whose surface is narrow. Especially in terms of secondary waste reduction, MHI started the study of application of Dry Ice Blast Decontamination to actual PWR plant. This paper provides an introduction to Dry Ice Blast Decontamination principle, its system and actual application result to PWR plant. (J.P.N.)

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.)

Solvent purification using a current of water vapour. A continuous process applicable to chemical plants treating irradiated fuels; Purification des solvants par entrainement a la vapeur d'eau. Procede continu applicable aux usines chimiques de traitement des combustibles irradies

Energy Technology Data Exchange (ETDEWEB)

Auchapt, P R; Sautray, R R; Girard, B R [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

1964-07-01

The pilot plant described in this report is intended for the continuous purification of the solvent used in the plutonium extraction plant at Marcoule, by separating the impurities (fission products). This physical separation is operated by carrying over in a water vapour stream. The contaminating products, only slightly volatile, remain in the form of the droplets and are separated; the vaporised solvent and the water vapour used are condensed and then separated. The originality of the installation resides in the system for pulverising the liquid and in the operating conditions: low working pressure and temperature. The systematic analysis of the various parameters (percentage of residue; flow, pressure and temperature ratios etc...) has shown their influence on the decontamination. The activity due to the zirconium-niobium is undetectable after treatment, and it is easy to obtain decontamination factors of 300 for the ruthenium. The, presence of uranium is favorable for the decontamination. As a conclusion, some extra-technical considerations are given concerning in particular the approximate cost price of the treated solvent per litre. (authors) [French] L'installation pilote decrite dans ce rapport est destinee a purifier, en continu, le solvant utilise a l'usine d'extraction du plutonium de Marcoule, en separant les impuretes (produits de fission). Cette separation physique est realisee par entrainement a la vapeur d'eau. Les produits contaminants, peu volatils, restant sous forme de gouttelettes, sont separes; le solvant vaporise ainsi que la vapeur d'entrainement sont condenses puis separes. L'originalite de l'installation reside dans le systeme de pulverisation du liquide et dans les conditions operatoires: faible pression et basse temperature de fonctionnement. L'analyse systematique des differents parametres (pourcentage de residus, rapport de debits, pression et temperature, etc...) a mis en evidence leur influence sur la decontamination. L'activite en

Effectiveness and reaction networks of H2O2 vapor with NH3 gas for decontamination of the toxic warfare nerve agent, VX on a solid surface.

Science.gov (United States)

Gon Ryu, Sam; Wan Lee, Hae

2015-01-01

The nerve agent, O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX) must be promptly eliminated following its release into the environment because it is extremely toxic, can cause death within a few minutes after exposure, acts through direct skin contact as well as inhalation, and persists in the environment for several weeks after release. A mixture of hydrogen peroxide vapor and ammonia gas was examined as a decontaminant for the removal of VX on solid surfaces at ambient temperature, and the reaction products were analyzed by gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance spectrometry (NMR). All the VX on glass wool filter disks was found to be eliminated after 2 h of exposure to the decontaminant mixtures, and the primary decomposition product was determined to be non-toxic ethyl methylphosphonic acid (EMPA); no toxic S-[2-(diisopropylamino)ethyl] methylphosphonothioic acid (EA-2192), which is usually produced in traditional basic hydrolysis systems, was found to be formed. However, other by-products, such as toxic O-ethyl S-vinyl methylphosphonothioate and (2-diisopropylaminoethyl) vinyl disulfide, were detected up to 150 min of exposure to the decontaminant mixture; these by-products disappeared after 3 h. The two detected vinyl byproducts were identified first in this study with the decontamination system of liquid VX on solid surfaces using a mixture of hydrogen peroxide vapor and ammonia gas. The detailed decontamination reaction networks of VX on solid surfaces produced by the mixture of hydrogen peroxide vapor and ammonia gas were suggested based on the reaction products. These findings suggest that the mixture of hydrogen peroxide vapor and ammonia gas investigated in this study is an efficient decontaminant mixture for the removal of VX on solid surfaces at ambient temperature despite the formation of a toxic by-product in the reaction process.

Surfaces: processing, coating, decontamination, pollution, etc. Surface mastering to prevent component corrosion; Surfaces: traitement, revetements, decontamination, pollution, etc. Maitrise de la surface pour prevenir la corrosion des composants

Energy Technology Data Exchange (ETDEWEB)

Foucault, M. [Departement Corrosion Chimie, AREVA Centre Technique, BP 181, 71205 Le Creusot (France)

2012-07-01

In the primary and secondary circuits of nuclear Pressurized Water Reactors, AREVA uses several nickel-based alloys or austenitic stainless steels for the manufacture of safety components. The experience feedback of the last twenty years allows us to point out the major role hold by the component surface state in their life duration. In this paper, we present four examples of problem encountered and solved by a surface study and the definition and implementation of processes for the surface control of the repaired components. Then, we propose some ideas about the present needs in term of analysis means to improve the surface knowledge and control of the manufactured components. (author)

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

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

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

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

Solvent purification using a current of water vapour. A continuous process applicable to chemical plants treating irradiated fuels; Purification des solvants par entrainement a la vapeur d'eau. Procede continu applicable aux usines chimiques de traitement des combustibles irradies

Energy Technology Data Exchange (ETDEWEB)

Auchapt, P.R.; Sautray, R.R.; Girard, B.R. [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

1964-07-01

The pilot plant described in this report is intended for the continuous purification of the solvent used in the plutonium extraction plant at Marcoule, by separating the impurities (fission products). This physical separation is operated by carrying over in a water vapour stream. The contaminating products, only slightly volatile, remain in the form of the droplets and are separated; the vaporised solvent and the water vapour used are condensed and then separated. The originality of the installation resides in the system for pulverising the liquid and in the operating conditions: low working pressure and temperature. The systematic analysis of the various parameters (percentage of residue; flow, pressure and temperature ratios etc...) has shown their influence on the decontamination. The activity due to the zirconium-niobium is undetectable after treatment, and it is easy to obtain decontamination factors of 300 for the ruthenium. The, presence of uranium is favorable for the decontamination. As a conclusion, some extra-technical considerations are given concerning in particular the approximate cost price of the treated solvent per litre. (authors) [French] L'installation pilote decrite dans ce rapport est destinee a purifier, en continu, le solvant utilise a l'usine d'extraction du plutonium de Marcoule, en separant les impuretes (produits de fission). Cette separation physique est realisee par entrainement a la vapeur d'eau. Les produits contaminants, peu volatils, restant sous forme de gouttelettes, sont separes; le solvant vaporise ainsi que la vapeur d'entrainement sont condenses puis separes. L'originalite de l'installation reside dans le systeme de pulverisation du liquide et dans les conditions operatoires: faible pression et basse temperature de fonctionnement. L'analyse systematique des differents parametres (pourcentage de residus, rapport de debits, pression et temperature, etc...) a mis en evidence leur influence

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.

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

Homogenous photocatalytic decontamination of prion infected stainless steel and titanium surfaces.

Science.gov (United States)

Berberidou, Chrysanthi; Xanthopoulos, Konstantinos; Paspaltsis, Ioannis; Lourbopoulos, Athanasios; Polyzoidou, Eleni; Sklaviadis, Theodoros; Poulios, Ioannis

2013-01-01

Prions are notorious for their extraordinary resistance to traditional methods of decontamination, rendering their transmission a public health risk. Iatrogenic Creutzfeldt-Jakob disease (iCJD) via contaminated surgical instruments and medical devices has been verified both experimentally and clinically. Standard methods for prion inactivation by sodium hydroxide or sodium hypochlorite have failed, in some cases, to fully remove prion infectivity, while they are often impractical for routine applications. Prion accumulation in peripheral tissues and indications of human-to-human bloodborne prion transmission, highlight the need for novel, efficient, yet user-friendly methods of prion inactivation. Here we show both in vitro and in vivo that homogenous photocatalytic oxidation, mediated by the photo-Fenton reagent, has the potential to inactivate the pathological prion isoform adsorbed on metal substrates. Photocatalytic oxidation with 224 μg mL(-1) Fe (3+), 500 μg mL(-1) h(-1) H 2O 2, UV-A for 480 min lead to 100% survival in golden Syrian hamsters after intracranial implantation of stainless steel wires infected with the 263K prion strain. Interestingly, photocatalytic treatment of 263K infected titanium wires, under the same experimental conditions, prolonged the survival interval significantly, but failed to eliminate infectivity, a result that we correlate with the increased adsorption of PrP(Sc) on titanium, in comparison to stainless steel. Our findings strongly indicate that our, user--and environmentally--friendly protocol can be safely applied to the decontamination of prion infected stainless steel surfaces.

Chemical decontamination method for radioactive metal waste

International Nuclear Information System (INIS)

Onuma, Tsutomu; Akimoto, Hidetoshi

1991-01-01

The invention relates to a decontamination method for radioactive metal waste products derived from equipment that handles radioactive materials whose surfaces have been contaminated; in particular it concerns a decontamination method that reduces the amount of radioactive waste by decontaminating radioactive waste substances to a level of radioactivity in line with normal waste products. In order to apply chemical decontamination to metal waste products whose surfaces are divided into carbon steel waste and stainless steel waste; the carbon steel waste is treated using only a primary process in which the waste is immersed in a sulfuric acid solution, while the stainless steel waste must be treated with both the primary process and then electrolytically reduces it for a specific length of time and a secondary process that uses a solution of sulfuric acid mixed with oxidizing metal salts. The method used to categorize metal waste into carbon steel waste and stainless steel waste involves determining the presence, or absence, of magnetism. Voltage is applied for a fixed duration; once that has stopped, electrolytic reduction repeats the operative cycle of applying, then stopping voltage until the potential of the radioactive metal waste is retained in the active region. 1 fig. 2 tabs

Laser-based characterization and decontamination of contaminated facilities

International Nuclear Information System (INIS)

Leong, K.H.; Hunter, B.V.; Grace, J.E.; Pellin, M.J.; Leidich, H.F.; Kugler, T.R.

1996-01-01

This study examines the application of laser ablation to the characterization and decontamination of painted and unpainted concrete and metal surfaces that are typical of many facilities within the US Department of Energy complex. The utility of this promising technology is reviewed and the essential requirements for efficient ablation extracted. Recent data obtained on the ablation of painted steel surfaces and concrete are presented. The affects of beam irradiance, ablation speed and efficiency, and characteristics of the aerosol effluent are discussed. Characterization of the ablated components of the surface offers the ability of concurrent determination of the level of contamination. This concept can be applied online where the ablation endpoint can be determined. A conceptual system for the characterization and decontamination of surfaces is proposed

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.)

Los Alamos DP West Plutonium Facility decontamination project, 1978-1981

International Nuclear Information System (INIS)

Garde, R.; Cox, E.J.; Valentine, A.M.

1982-09-01

The DP West Plutonium Facility operated by the Los Alamos National Laboratory, Los Alamos, New Mexico was decontaminated between April 1978 and April 1981. The facility was constructed in 1944 to 1945 to produce plutonium metal and fabricate parts for nuclear weapons. It was continually used as a plutonium processing and research facility until mid-1978. Decontamination operations included dismantling and removing gloveboxes and conveyor tunnels; removing process systems, utilities, and exhaust ducts; and decontaminating all remaining surfaces. This report describes glovebox and conveyor tunnel separations, decontamination techniques, health and safety considerations, waste management procedures, and costs of the operation

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

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

Comparison of Selected Methods for Individual Decontamination of Chemical Warfare Agents

OpenAIRE

Tomas Capoun; Jana Krykorkova

2014-01-01

This study addresses the individual decontamination of chemical warfare agents (CWA) and other hazardous substances. The individual decontamination applies to contaminated body surfaces, protective clothing and objects immediately after contamination, performed individually or by mutual assistance using prescribed or improvised devices. The article evaluates the importance of individual decontamination, security level for Fire and Rescue Service Units of the Czech Republic (FRS CR) and demons...

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

Surface decontamination in the old storage shed number 99 of the General Plan of IPEN/CNEN-SP, containing production equipment of natural uranium hexafluoride (UF6), aiming at its decommissioning

International Nuclear Information System (INIS)

Almeida, Claudio C. de; Cambises, Paulo B.S.; Paiva, Julio E. de; Paiva, Julio E. de; Silva, Teresina M.; Rodrigues, Demerval L.

2013-01-01

This paper presents the steps adopted in the operation planned for the decontamination of surfaces in the old storage shed number 99 the general layout of the Energy Research and Nuclear IPEN-CNEN/SP, Brazil, and contained various types of equipment originating from production hexafluoride natural uranium (UF6). This operation involved the planning, training of operators of the facility, analysis of workplaces and radiometric surveys for monitoring of external radiation and surface contamination. The training involved the procedures for decontamination of surfaces, segregation of materials and practical procedures for individual monitoring of contamination outside of the body. Were also established rules for the transport of radioactive materials in the internal and external facility and release of material and sites already decontaminated

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)

Decontamination of surfaces by blasting with crystals of H2O and CO2

International Nuclear Information System (INIS)

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

1995-02-01

A major mission of the US Department of Energy during the 1990s is site and environmental cleanup. In pursuit of this mission, numerous remediation projects are under way and many others are being planned at Oak Ridge National Laboratory (ORNL). In this report, tests using two proposed methods for decontaminating surfaces one using water ice crystals [Crystalline Ice Blast (CIB)], the other using dry ice crystals (CO 2 Cleanblast trademark) -- are described. Both methods are adaptations of the commonly used sand blasting technology. The two methods tested differ from sand blasting in that the particles are not particularly abrasive and do not accumulate as particles in the wastes. They differ from each other in that the CO 2 particles sublime during and after impact and the ice particles melt. Thus, the two demonstrations provide important information about two strong candidate decontamination methodologies. Each process was tested at ORNL using contaminated lead bricks and contaminated tools and equipment. Demonstrations with the prototype Crystalline Ice Blast and the CO 2 Cleanblast systems showed that paint, grease, and oil can be removed from metal, plastic, asphalt, and concrete surfaces. Furthermore, removal of contamination from lead bricks was highly effective. Both processes were found to be less effective, under the conditions tested, with contaminated tools and equipment that had chemically bonded contamination or contamination located in crevices since neither technology abrades the substrates or penetrates deeply into crevices to remove particulates. Some process improvements are recommended

Decontamination of radionuclides on construction materials

International Nuclear Information System (INIS)

Samuleev, P.V.; Andrews, W.S.; Creber, K.A.M.; Velicogna, D.

2013-01-01

A wide variety of materials can become contaminated by radionuclides, either from a terrorist attack or an industrial or nuclear accident. The final disposition of these materials depends, in large part, on the effectiveness of decontamination measures. This study reports on investigations into the decontamination of a selection of building materials. The aim has been to find an effective, easy-to-use and inexpensive decontamination system for radionuclides of cesium and cobalt, considering both the chemical and physical nature of these potential contaminants. The basic method investigated was surface washing, due to its ease and simplicity. In the present study, a basic decontamination formulation was modified by adding isotope-specific sequestering agents, to enhance the removal of cesium(I) and cobalt(II) from such construction materials as concrete, marble, aluminum and painted steel. Spiking solutions contained 134 Cs or 60 Co, which were prepared by neutron activation in the SLOWPOKE-2 nuclear reactor facility at the Royal Military College of Canada. Gamma spectroscopy was used to determine the decontamination efficiency. The results showed that the addition of sequestering agents generally improved the radiological decontamination. Although the washing of both cesium and cobalt from non-porous materials, such as aluminum and painted steel, achieved a 90-95 % removal, the decontamination of concrete and marble was more challenging, due to the porous nature of the materials. Nevertheless, the removal efficiency from 6-year-old concrete increased from 10 % to approximately 50 % for cobalt(II), and from 18 to 55 % for cesium(I), with the use of isotope binding agents, as opposed to a simple water wash. (author)

Growth of micrometric oxide layers to explore laser decontamination of metallic surfaces

Directory of Open Access Journals (Sweden)

Carvalho Luisa

2017-01-01

Full Text Available The nuclear industry produces a wide range of radioactive waste in terms of hazard level, contaminants and material. For metallic equipment like steam generators, the radioactivity is mainly located in the oxide surface. In order to study and develop safe techniques for dismantling and for decontamination, it is important to have access to oxide layers with a representative distribution of non-radioactive contaminants. In this paper we propose a method for the creation of oxide layers on stainless steel 304L with europium (Eu as contaminant. This technique consists in spraying an Eu-solution on stainless steel samples. The specimens are firstly treated with a pulsed nanosecond laser after which the steel samples are placed in a 873 K furnace for various durations in order to grow an oxide layer. The oxide structure and in-depth distribution of Eu in the oxide layer were analyzed by scanning electron microscopy coupled to an energy-dispersive X-ray microanalyzer, as well as by glow discharge optical emission or mass spectrometry. The oxide layers were grown to thicknesses in the range of 200 nm–4.5 μm depending on the laser treatment parameters and the heating duration. These contaminated oxides had a ‘duplex structure’ with a mean concentration of the order of 6 × 1016 atoms/cm2 (15 μg/cm2 of europium in the volume of the oxide layer. It appears that europium implementation prevented the oxide growth in the furnace. Nevertheless, the presence of the contamination had no impact on the thickness of the oxide layers obtained by preliminary laser treatment. These oxide layers were used to study the decontamination of metallic surfaces such as stainless steel 304L using a nanosecond pulsed laser.

Contribution to the study of external decontamination procedure. Experiments on a new product in the case of radioactive contamination of the teguments

International Nuclear Information System (INIS)

Toulet, J.; Tabernat, J.

1959-01-01

General principles of external decontamination with elements of practical organisation in a centre of nuclear studies. Reprint of a paper published in 'Archives des Maladies Professionnelles', Tome 20, n. 3, 1959, p. 272-282

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

Design of a tritium decontamination workstation based on plasma cleaning

International Nuclear Information System (INIS)

Antoniazzi, A.B.; Shmayda, W.T.; Fishbien, B.F.

1993-01-01

A design for a tritium decontamination workstation based on plasma cleaning is presented. The activity of tritiated surfaces are significantly reduced through plasma-surface interactions within the workstation. Such a workstation in a tritium environment can routinely be used to decontaminate tritiated tools and components. The main advantage of such a station is the lack of low level tritiated liquid waste. Gaseous tritiated species are the waste products with can with present technology be separated and contained

Decontamination of outdoor school swimming pools in Fukushima

International Nuclear Information System (INIS)

Saegusa, Jun

2013-01-01

After the Fukushima Daiichi NPP accident following the Great East Japan Earthquake, many school swimming pools in Fukushima have suspended water discharge, due to concerns that pool water which contains radioactive fallout is discharged into a river or waterway for agricultural use. The Japan Atomic Energy Agency conducted researches and examinations on the existing absorbent method and the flocculation method as ways for decontaminating pool water. By reviewing and improving these methods through decontamination demonstrations at eight pools in Fukushima, a practical decontamination method for outdoor pools has been established. This report summarizes the methods and results of the decontamination demonstrations carried out at the schools. Also, the surface density of fallout estimated at one of the pools is also presented and discussed in connection with the overall collection ratio of radiocesium at the pool. (author)

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

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

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.

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

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.

Decontamination of Belarus research reactor installation by strippable coatings

International Nuclear Information System (INIS)

Voronik, N.I.; Shatilo, N.N.

2002-01-01

The goal of this study was to develop new strippable coatings using water-based solutions of polyvinyl alcohol and active additives for decontamination of research reactor equipment. The employment of strippable coatings makes it possible to minimize the quantity of liquid radioactive waste. The selection of strippable decontaminating coatings was carried out on the basis of general requirements to decontaminating solutions: successfully dissolve corrosion deposits; ensure the desorption of radionuclides from the surfaces and the absence of resorption; introduce minimal corrosion effect of construction materials; to be relatively cheap and available in reagents. The decontaminating ability and adhesion properties of these coatings depending on metal and deposit sorts were investigated. Research on the chemical stability of solid wastes was carried out. The data obtained were the base for recommendations on waste management procedure for used films and pastes. A full-scale case-study analysis was performed for comparing strippable coatings with decontaminating solutions. (author)

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

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

Decontamination Efficacy and Skin Toxicity of Two Decontaminants against Bacillus anthracis.

Directory of Open Access Journals (Sweden)

Chad W Stratilo

Full Text Available Decontamination of bacterial endospores such as Bacillus anthracis has traditionally required the use of harsh or caustic chemicals. The aim of this study was to evaluate the efficacy of a chlorine dioxide decontaminant in killing Bacillus anthracis spores in solution and on a human skin simulant (porcine cadaver skin, compared to that of commonly used sodium hypochlorite or soapy water decontamination procedures. In addition, the relative toxicities of these decontaminants were compared in human skin keratinocyte primary cultures. The chlorine dioxide decontaminant was similarly effective to sodium hypochlorite in reducing spore numbers of Bacillus anthracis Ames in liquid suspension after a 10 minute exposure. After five minutes, the chlorine dioxide product was significantly more efficacious. Decontamination of isolated swine skin contaminated with Bacillus anthracis Sterne with the chlorine dioxide product resulted in no viable spores sampled. The toxicity of the chlorine dioxide decontaminant was up to two orders of magnitude less than that of sodium hypochlorite in human skin keratinocyte cultures. In summary, the chlorine dioxide based decontaminant efficiently killed Bacillus anthracis spores in liquid suspension, as well as on isolated swine skin, and was less toxic than sodium hypochlorite in cultures of human skin keratinocytes.

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

The characteristics of per-fluorocarbon compounds (PFC) are colorless, non-toxic, easily vaporized and nonflammable. Also, some of them are liquids of a high density, low surface tension, low latent heat and low specific heat. These particular chemical and physical properties of fluoro-organic compounds permit their use in very different fields such as electronics, medicine, tribology, nuclear and material science. The Sonatol process was developed under a contract with the DOE. The Sonatol process uses an ultrasonic agitation in a PFC solution that contains a fluorinated surfactant to remove radioactive particles from surfaces. Filtering the suspended particles allows the solutions to be reused indefinitely. They applied the Sonatol process to the decontamination of a heterogeneous legacy Pu-238 waste that exhibited an excessive hydrogen gas generation, which prevents a transportation of such a waste to a Waste Isolation Pilot Plant. Korea Atomic Energy Research Institute (KAERI) is developing dry decontamination technologies applicable to a decontamination of a highly radioactive area loosely contaminated with radioactive particles. This contamination has occurred as a result of an examination of a post-irradiated material or the development of the DUPIC process. The dry decontamination technologies developed are the carbon dioxide pellet spray method and the PFC spray method. As a part of the project, PFC ultrasonic decontamination technology was developed in 2004. The PFC spray decontamination method which is based on the test results of the PFC ultrasonic method has been under development since 2005. The developed PFC spray decontamination equipment consists of four modules (spray, collection, filtration and distillation). Vacuum cup of the collection module gathers the contaminated PFC solution, then the solution is moved to the filtration module and it is recycled. After a multiple recycling of the spent PFC solution, it is purified in the distillation

Evaluation of decontamination during dismantling of plutonium-contaminated glove boxes

International Nuclear Information System (INIS)

Kinugasa, Manabu; Taguchi, Seigi; Ohzeki, Satoru; Inoue, Yoshiaki; Kashima, Sadamitsu

1981-01-01

The dismantling work of plutonium-contaminated glove boxes was carried out. These glove boxes had been used for the R and D of plutonium-uranium mixed oxide fuel for 15 years. The work was carried out in a pressure-controlled greenhouse, and the contamination of air in the greenhouse was monitored continuously. In order to reduce the contamination of air during dismantling, the decontamination and fixation of loose contaminants on the surfaces of glove boxes were very important. The correlation between decontamination and the contamination of air regarding dismantling is reported in this paper. The surface contamination density of the glove boxes was measured utilizing the smear method before and after the decontamination, and the decontamination effects were estimated. The contamination of air during dismantling was continuously measured with a plutonium dust monitor. It was found that loose contamination exponentially decreased by the decontamination process. When the so-called wet glove boxes, which contained wet recovery and waste disposal apparatus, were dismantled, the contamination of air did not exceed 500 (MPC) a. However, the contamination of air exceeded 500 (MPC) a several times in the present work of dismantling the so-called dry glove boxes which had been used for the fabrication of plutonium-uranium mixed oxide pellets. (Kato, T.)

Growth of micrometric oxide layers for the study of metallic surfaces decontamination by laser

Science.gov (United States)

Carvalho, Luisa; Pacquentin, Wilfried; Tabarant, Michel; Maskrot, Hicham; Semerok, Alexandre

2017-09-01

The nuclear industry produces a wide range of radioactive waste in term of level of hazard, contaminants and material. For metallic equipment like steam generators, the radioactivity is mainly located in the oxide surface. In order to study and develop techniques for dismantling and for decontamination in a safe way, it is important to have access to oxide layers with a representative distribution of non-radioactive contaminants. We propose a method of formation of oxide layer on stainless steel 304L with europium (Eu) as contaminant marker. In this method, an Eu-solution is sprayed on the stainless steel samples. The specimen are firstly treated with a pulsed nanosecond laser and secondly the steel samples are exposed to a 600°C furnace for various durations in order to grow an oxide layer. The oxide structure and in-depth distribution of Eu in the oxide layer are analysed by scanning electron microscopy coupled with energy dispersive X-ray microanalyzer, and by glow discharge optical emission or mass spectrometry. The oxide layers were grown to thicknesses in the range of 200 nm to 4.5 μm regarding to the laser treatment parameters and the heating duration. These contaminated oxides have a `duplex structure' with a mean weight percentage of 0.5% of europium in the volume of the oxide layer. It appears that europium implementation prevents the oxide growth by furnace but has no impact on laser heating. These oxide layers are used to study the decontamination of metallic surfaces such as stainless steel 304L using a nanosecond pulsed laser.

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

Dresses problems arising from hot-plant operation and their solution (1961); Les problemes vestimentaires poses par l'exploitation des installations actives et leurs solutions (1961)

Energy Technology Data Exchange (ETDEWEB)

Rodier, J; Bouzigues, H; Boutot, P [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

1961-07-01

This article deals with effective methods to struggle radioactive contamination using rationally designed working clothes. The choice of the cloth is important and cotton, because of its absorbent properties constitutes an effective barrier to radioelements failing on its surface. Clothing the personnel of large nuclear industrial concerns is a big problem which can only be solved by carefully studied methods. The decontamination and washing of large amounts of clothes whose flow increases during periods of radio-active incidents have to be treated as are those operations in hospital laundering. Linen washing by the German counter-current method (the Sulzman system) is of great value because of the volume which can be treated and, more important, because of the small amount of liquid waste produced. Dry cleaning is certainly a method of the future and is even more economic than the preceding one. In 'active' laundries, the control of clothing for residual contamination can constitute a serious bottleneck in the production of clean clothing if automatic high-speed machines are not used. The risk to the operating personnel comes solely from contamination of the atmosphere and of the surfaces. Because of this, the plant must be considered as an active zone in which are handled several tens of millicuries of dangerous emitters and several micro- curies of plutonium daily. (authors) [French] Ce memoire traite des moyens efficaces de lutte contre la contamination radioactive que peuvent offrir des vetements de travail de conception rationnelle. Le choix du tissu est un element important et la fibre de coton, par ses proprietes absorbantes, constitue un excellent barrage aux radioelements deposes a sa surface. L'habillement du personnel des grands ensembles industriels de l'energie atomique est un gros probleme qui ne peut etre solutionne qu'avec des moyens soigneusement etudies. La decontamination et le lavage des grandes quantites de vetements renouveles a cadence

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

Radiation treatment of surface and sewage waters and decontamination of effluents from livestock farms

International Nuclear Information System (INIS)

Brusentseva, S.A.; Dolin, P.I.; Fel', N.S.

1983-01-01

The report deals with the use of high level radiation for treatment of surface and sewage waters. The surface water radiation treatment at the dose of 0,1 Mrad produces a complex effect of color, taste and odor control and desinfection of water. In order to reduce the cost of radiation it is necessary to use the synergistic effect and optimization of treatment. Sewage from animal breeding complexes was studied during the introduction of air and ammonia. E. coli, salmonellum and staphylloccocus aureus were used as test microorganisms (10 4 -10 6 cell/ml). The sources of radiation-accelerators (energy 8 and 0.4 MeV, dose rates 0.1-10 2 Krad/s). When air and ammonia are introduced into the sewage the adequate decontamination dose is 4-5 times reduced. (author)

Low pressure water vapour plasma treatment of surfaces for biomolecules decontamination

DEFF Research Database (Denmark)

Fumagalli, F; Kylian, O; Amato, Letizia

2012-01-01

Decontamination treatments of surfaces are performed on bacterial spores, albumin and brain homogenate used as models of biological contaminations in a low-pressure, inductively coupled plasma reactor operated with water-vapour-based gas mixtures. It is shown that removal of contamination can...... be achieved using pure H2O or Ar/H2O mixtures at low temperatures with removal rates comparable to oxygen-based mixtures. Particle fluxes (Ar+ ions, O and H atomic radicals and OH molecular radicals) from water vapour discharge are measured by optical emission spectroscopy and Langmuir probe under several...... operating conditions. Analysis of particle fluxes and removal rates measurements illustrates the role of ion bombardment associated with O radicals, governing the removal rates of organic matter. Auxiliary role of hydroxyl radicals is discussed on the basis of experimental data. The advantages of a water...

Laser decontamination of metallic - Metallic surfaces decontamination by using Laser light

International Nuclear Information System (INIS)

Moggia, F.; Objois, L.; Toulemonde, V.

2014-01-01

Within the next years, the volume of metallic contaminated with radionuclides will get higher. In that way, the development of new efficient decontamination methods appears to be a promising challenge for industrials as AREVA. Today, even if a few methods already exist, some of them point out a lack of efficiency and for the others, a production of secondary waste not compatible with the actual requirements. Based on this observation, we started the study of a new process based on the Laser technology. This technology is very promising in terms of effectiveness and waste minimization. Since a couple of years we went through an intensive experimental program (including active and non active tests, metallographic observations...) to fully describe this technology and also to prove its interest for our industry. (authors)

Contribution to the study of physico-chemical properties of surfaces modified by laser treatment. Application to the enhancement of localized corrosion resistance of stainless steels; Contribution a l'etude des proprietes physico-chimiques des surfaces modifiees par traitement laser. Application a l'amelioration de la resistance a la corrosion localisee des aciers inoxydables

Energy Technology Data Exchange (ETDEWEB)

Pacquentin, W.

2011-11-25

Metallic materials are more and more used in severe conditions with particularly strong request for improving their behavior in aggressive environment and especially over long periods. The objective of this PhD work is to estimate the potentiality of a laser surface melting treatment on the improvement of the stainless steel 304L corrosion resistance, surface treatments by laser can be revisited on the basis of a recent change in the laser technology. In the frame of this work, a nano-pulsed laser fiber was chosen: it allows the treated surface to be melted for few microns in depth, followed by an ultra-fast solidification occurring with cooling rates up to 1011 K/s. The combination of these processes leads to the elimination of the surface defects, the formation (trapping) of metastable phases, the segregation of chemical elements and the growth of a new oxide layer which properties are governed by the laser parameters. To correlate these latter to the electrochemical reactivity of the surface, the influence of two laser parameters on the physico-chemical properties of the surface was studied: the laser power and the overlap of the laser impacts. To support this approach, the pitting corrosion resistance of the samples was determined by standard electrochemical tests. For specific laser parameters, the pitting potential of a 304L stainless steel was increased by more than 500 mV corresponding to an important enhancement in localized corrosion resistance in chloride environment. The interdependence of the different phenomena resulting from the laser treatment lead to a quite complex prioritization of their role on the sensibility of the 304L. However, it was demonstrated that the nature of the thermal oxide formed during the laser surface melting and the induced defects are first-order parameters for the initiation of pits. (author) [French] Les materiaux metalliques sont utilises dans des conditions de plus en plus severes et doivent presenter une parfaite

Experimental studies on decontamination in first aid for contaminated wounds

International Nuclear Information System (INIS)

Kusama, Tomoko; Ogaki, Kazushi; Yoshizawa, Yasuo

1982-01-01

The present study was designed to investigate the decontamination procedures in first aid for wounds contaminated with radionuclides. Abrasion of mouse skin was contaminated with 58 CoCl 2 . Irrigation by decontamination fluids began at 2 min after administration of the radionuclide and continued for 14 min. Tap water, 0.5% Hyamine solution or 10% Ca-DTPA solution were used as the decontamination fluids. Radioactivities of whole body, wounded skin surface and washed solution were measured with an animal counter with 5 cm NaI(Tl) and a well-type auto-gamma-counter. Decontamination effectiveness were expressed as follows: (1) absorption rate of radionuclide through the wound and (2) residual rate of radionuclide on the wound. More than 20% of the radionuclide applied on the wounded skin was absorbed in 15 min after contamination. The absorption rate decreased to 2% by the decontamination procedures. The Ca-DTPA solution reduced the residual rate of radionuclide on the wounds. The results suggested that the decontamination for the contaminated wounds should begin as soon as possible. Irrigation with 0.5% Hyamine solution has been advocated for the decontamination in the first aid. (author)

Chemical decontamination method for radioactive metal waste

International Nuclear Information System (INIS)

Onuma, Tsutomu; Tanaka, Akio; Shibuya, Sadao.

1991-01-01

When contaminants mainly composed of copper remained on the surface of stainless steel wastes sent from an electrolytic reduction as a first step are chemically decontaminated, metal wastes are discriminated to carbon steel wastes and stainless steel wastes. Then, the carbon steel wastes are applied only with the first step of immersing in a sulfuric acid solution, and stainless steel wastes are applied with a first step of immersing into a sulfuric acid solution for electrolytic reduction for a predetermined period of time and a second step of immersing into a liquid in which an oxidative metal salt is added to sulfuric acid. The decontamination liquid which is used for immersing the stainless steel wastes in the second step and the oxidation force of which is lowered is used as the sulfuric acid solution in the first step for the carbon steel wastes. In view of the above, the decontamination liquid of the second step can be utilized most effectively, enabling to greatly decrease the secondary wastes and to improve decontamination efficiency. (T.M.)

Decontamination of the chemical crane room and decontamination and decommissioning of the extraction chemical room at the West Valley Demonstration Project

International Nuclear Information System (INIS)

Phillips, E.C.; Golden, M.P.

1986-01-01

This paper describes the decontamination of the Chemical Crane Room (CCR) of the West Valley Plant and the Extraction Chemical Room (XCR) from radioactively contaminated conditions to essentially shirt sleeve environments. In both cases, subsequent use re-contaminated the rooms. Prior to decontamination, general exposure rates in the CCR were 50 to 100 mR/hr with hot spots as high as 2000 mR/hr. Smearable levels on the floor were in the range of 10 5 to 10 6 dpm per 100/cm 2 . Respiratory protection was mandatory for entry. In the Extraction Chemical Room (XCR) prior to decontamination and decommissioning (D/D), radiological surveys indicated a maximum radiation field of 5 mR/hr, due to sources internal to the room, and 20,000 dpm beta/100 cm 2 surface contamination. A radiation source external to the XCR caused a hot spot with a 9 mR/hr exposure rate inside the XCR. The CCR, located at the north end of the Chemical Process Cell (CPC) is for the storage and servicing of two bridge cranes used in the CPC. Decontamination and exposure reduction in the CCR has been completed using vacuum cleaning, damp wipe down, and surface grinding followed by shielding and painting. The decontamination and decommissioning of the Extraction Chemical Room (XCR), located on the fifth floor elevation (160') of the reprocessing plant at the WVDP, has been completed. D/D operations included removal of piping, tanks, supports, and equipment to provide a clean work area of about 3000 square feet and 17 feet high

Chemical and Biological Substances Decontamination Study for Mars Missions and Terrestrial Applications

Science.gov (United States)

Pottage, Thomas; Walker, James; Bennett, Allan; Vrublevskis, John; Hovland, Scott

This study, funded by the European Space Agency (ESA) and undertaken by the Health Protec-tion Agency, UK supported by Systems Engineering and Assessment Ltd., was devised to select suitable current decontamination technologies for development for future manned missions to the Moon and Mars. There is a requirement to decontaminate the habitat module due to the concerns about astronaut ill health, microbial deterioration of materials and potential forward contamination in the case of Mars. In the case of the MIR space station, biodeterioration of components and materials occurred, and dangerous levels of airborne microorganisms were detected during air sampling procedures which lead to the introduction of microbial exposure limits (as MORD SSP 50260) to ensure the health of the crew. COSPAR planetary protection guidelines highlight the need to reduce any potential forward or backwards contamination issues that may occur through the use of Extra Vehicular Activity (EVA) suits whilst on Mars. Decontamination of the suit exterior must be completed before any EVA activity on Mars, whilst a further decontamination cycle must be completed after entry to the airlock following EVA. Technologies and techniques have also been investigated for the microbial reduction of the interior surfaces of the EVA suit to stop biodeterioration of the materials and protect the user from pathogenic microbe accumulation. The first work package reviewed the systems description and requirements as detailed in the statement of work. The requirements were broken down into 12 further requirement sections, where they were updated and expanded, resulted in Technical Note (TN) 1 which was then used as the base document for WP2 and WP3. WP2 investigated the current technologies available for the decontamination of the habitat module interior on missions of up to 6 months and missions that have durations of greater than 6 months. A comprehensive review was carried out for the different methods that

Stainless steel electrochemical behaviour - application to the decontamination of steel parts contaminated by tritium

International Nuclear Information System (INIS)

Bellanger, G.

1991-01-01

This purpose of this work is the study of an electrochemical decontamination process of stainless steel in which tritium is present on the surface of the metal, in the oxide layer and in the metal. We have first investigated the behaviour of the oxide layer. Then we have studied the hydrogen evolution, its diffusion and retrodiffusion in the metal. The results are applied to the decontamination of steel parts contamined by tritium. Part of the tritium can be eliminated by reducing the oxyde layer, which contains large amounts of tritium. However, it is more beneficial to electrolyse at the potential at which the H + ions are reduced. The hydrogen on the steel surface enters in the metal and displaces most of tritium located in the metallic layers near the surface. The tritium surface elimination rate is about 95%. The tritium eliminated through electrolysis is only a small fraction of all the tritium contained in the metal. However, according to conservation experiments of parts after electrolysis, it can be concluded that hydrogen, probably more strongly bound than tritium to steel, forms near the surface a barrier that prevents tritium retrodiffusion. Electrolysis appears as a satisfactory process for the surface decontamination of slightly tritiated steel parts. A decontamination automaton based on the preceding results is described using a pad electrolyser. This type of decontamination is little polluting, and the parts can be recycled after the in situ treatment [fr

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

Bioinspired Surface Treatments for Improved Decontamination: Silicate-Based Slippery Liquid-Infused Porous Surfaces (SLIPS)

Science.gov (United States)

2017-07-20

2 Fig. 2 — Nitrogen Adsorption / Desorption for MSS...Coatings ............................................................ 3 Fig. 3 — Nitrogen Adsorption / Desorption for the Fluorinated Coatings... environment including contamination avoidance, individual protection, collective protection, and decontamination. In January 2015, the Center for Bio

Fast sorting measurement technique to determine decontamination priority

International Nuclear Information System (INIS)

Distenfeld, C.H.; Brosey, B.; Igarashi, H.

1986-01-01

The method used to select decontamination priorities for the Three Mile Island Unit 2 (TMI-2) reactor building (RB) is systematic, but costs in personnel exposure and time must be borne. One way of minimizing exposure is to define and treat the one or two surface sources that are important contributors to the collective dose of the recovery personnel. Surface characteristics can then be determined and decontamination techniques developed to match the removal requirements. At TMI-2, a fast sorting technique was developed and used to prioritize surfaces for exposure reduction. A second quick sort can then be used to determine the next generation of surface characterization, decontamination method selection, and performance. The quick-sort method that was developed is based on the Eberline HP 220A probes directional survey system. The angular response of the HP 220A probes approaches 2 pi steradians and allows toward-away type measurements. Sources distributed over 4 pi steradians are hard to define with this system. Angular differentiation was improved to about pi/2 steradians by redesigning the probe shield. The change allows unambiguous six-direction measurements, such as up, down, front, rear, right, and left with practically no angular overlap or exclusion. A simple, light-weight stand was used to establish an angular reference for the rectangular packaged probe. The six surface planes of the rectangle work with the angular reference to establish the six viewing angles

Resorption of radionuclides through the surface of thermal burns and problems of decontamination

International Nuclear Information System (INIS)

Il'in, L.A.; Ivannikov, A.T.; Popov, B.A.; Parfenova, I.M.

1981-01-01

Resorption of sup(137)Cs, sup(89)Sr, sup(131)I, sup(241)Am during thermal burns of 1-3 degrees and choice of a decontamination method used simultaneously for decontamination and disinfection of burn wounds were studied. It is shown that a degree of burns effects in a certain form on skin penetrability: through burns of 1-2 degrees the resorption increases 1 5-3 times, through burns of the thir degree the resorption decreases slightly as compared to the resorption through intact skin. High efficiency of 3% soap solution for removing radionuclides from burn csurfae of skin has been established. For burns accompanied with the disturbance of epidermis integrality, when considerable absorption of radionuclides is possible, decontamination must be accomplished as soon and complete as possible [ru

Reaction-diffusion models of decontamination

DEFF Research Database (Denmark)

Hjorth, Poul G.

A contaminant, which also contains a polymer is in the form of droplets on a solid surface. It is to be removed by the action of a decontaminant, which is applied in aqueous solution. The contaminant is only sparingly soluble in water, so the reaction mechanism is that it slowly dissolves...

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)

Definition of a concrete bio-decontamination process in nuclear substructures

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 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)

Cesium powder and pellets inner container decontamination method determination

International Nuclear Information System (INIS)

Ferrell, P.C.

1998-01-01

The cesium powder and pellets inner container is to be performance tested per the criteria specified in Section 4.0 of HNF-2399, ''Design, Fabrication, and Assembly Criteria for Cesium Powder and Pellet Inner Container.'' The test criteria specifies that the inner container be water tight during decontamination of the exterior surface. Three prototypes will be immersed into a pool of water to simulate a water decontamination process

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.

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

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.

Method for electrochemical decontamination of radioactive metal

Science.gov (United States)

Ekechukwu, Amy A [Augusta, GA

2008-06-10

A decontamination method for stripping radionuclides from the surface of stainless steel or aluminum material comprising the steps of contacting the metal with a moderately acidic carbonate/bicarbonate electrolyte solution containing sodium or potassium ions and thereafter electrolytically removing the radionuclides from the surface of the metal whereby radionuclides are caused to be stripped off of the material without corrosion or etching of the material surface.

Plasma Decontamination of Space Equipment for Planetary Protection

Science.gov (United States)

Thomas, Hubertus; Barczyk, Simon; Rettberg, Petra; Shimizu, Satoshi; Shimizu, Tetsuji; Klaempfl, Tobias; Morfill, Gregor; Zimmermann, Julia; Weber, Peter

The search for extraterrestrial life is one of the most challenging science topics for the next decades. Space missions, like ExoMars, plan to land and search for biological remnants on planets and moons in our nearby Solar system. Planetary protection regulations defined by COSPAR prevent that during the mission biological contamination of the bodies occur through the space probes. Therefore decontamination of the probes and more general space equipment is necessary before the launch. The up-to-date accepted decontamination procedure originate from the old NASA Viking missions and use dry heat (T>110°C for 30h) - a technology not well suited for sensitive equipment nowadays. We investigated in a study financed by the German Space Agency* cold atmospheric plasma (CAP) as an alternative for such decontamination. It is well known that CAP can kill bacteria or spores within seconds or minutes, respectively, if the plasma is in direct contact with the treated sample. This procedure might also be quite aggressive to the treated surface materials. Therefore, we developed an afterglow CAP device specially designed for the soft treatment of space equipment. Afterglow plasma produced by a SMD device in air is transported into a “larger” treatment chamber where the samples are positioned. It could be shown that samples of different bacteria and spores, the latter defined by COSPAR as a means to show the effectiveness of the decontamination process, positioned on different materials (steel, Teflon, quartz) could be effectively inactivated. The surface materials were investigated after the plasma treatment to identify etching or deposition problems. The afterglow in the treatment chamber could even overcome obstacles (tubes of different height and diameter) which simulate more complicated structures of the relevant surfaces. Up to now, CAP looks like a quite promising alternative to decontaminate space equipment and need to be studied in greater detail in the near future

Examining the decontaminability of surfaces from the beginnings of nuclear technology

International Nuclear Information System (INIS)

Kunze, S.

2003-01-01

Parallel with the development of nuclear technology in the 1950s, methods of examining the decontaminability of surface materials were elaborated, improved, and partly standardized in many countries. In 1988, ISO 8690 was adopted as an internationally accepted method of examination (technically identical to DIN 25 415, Part 1). A first range of coatings for nuclear applications were compiled from the large number of commercial products available on the market on the basis of the test method developed since 1962 at the Karlsruhe Nuclear Research Center and then at the Karlsruhe Research Center. Subsequently, the continuously improved test method was used to study, in mainly chemically curing two-component coatings, the reduction of gloss by dulling agents and fillers as well as various shades of color. Floor and container coatings were also examined for their resistance to radiation and to chemicals as well as wear. (orig.) [de

Effect of decontamination on nuclear power plant primary circuit materials

International Nuclear Information System (INIS)

Brezina, M.; Kupca, L.

1991-01-01

The effect of repeated decontamination on the properties of structural materials of the WWER-440 primary coolant circuit was examined. Three kinds of specimens of 08Kh18Ni10T steel were used for radioactivity-free laboratory experiments; they included material obtained from assembly additions to the V-2 nuclear power plant primary piping, and a sheet of the CSN 17247 steel. Various chemical, electrochemical and semi-dry electrochemical decontamination procedures were tested. Chemical decontamination was based on the conventional AP(20/5)-CITROX(20/20) procedure and its variants; NP-CITROX type procedures with various compositions were also employed. Solutions based on oxalic acid were tested for the electrochemical and semi-dry electrochemical decontamination. The results of measurements of mass losses of the surfaces, of changes in the corrosion resistance and in the mechanical properties of the materials due to repeated decontamination are summarized. (Z.S.). 12 figs., 1 tab., 8 refs

Growth of micrometric oxide layers for the study of metallic surfaces decontamination by laser

Directory of Open Access Journals (Sweden)

Carvalho Luisa

2017-01-01

Full Text Available The nuclear industry produces a wide range of radioactive waste in term of level of hazard, contaminants and material. For metallic equipment like steam generators, the radioactivity is mainly located in the oxide surface. In order to study and develop techniques for dismantling and for decontamination in a safe way, it is important to have access to oxide layers with a representative distribution of non-radioactive contaminants. We propose a method of formation of oxide layer on stainless steel 304L with europium (Eu as contaminant marker. In this method, an Eu-solution is sprayed on the stainless steel samples. The specimen are firstly treated with a pulsed nanosecond laser and secondly the steel samples are exposed to a 600°C furnace for various durations in order to grow an oxide layer. The oxide structure and in-depth distribution of Eu in the oxide layer are analysed by scanning electron microscopy coupled with energy dispersive X-ray microanalyzer, and by glow discharge optical emission or mass spectrometry. The oxide layers were grown to thicknesses in the range of 200 nm to 4.5 μm regarding to the laser treatment parameters and the heating duration. These contaminated oxides have a ‘duplex structure’ with a mean weight percentage of 0.5% of europium in the volume of the oxide layer. It appears that europium implementation prevents the oxide growth by furnace but has no impact on laser heating. These oxide layers are used to study the decontamination of metallic surfaces such as stainless steel 304L using a nanosecond pulsed laser.

New method for studying the efficiency of chelating agents of the polyamine acid series for internal decontamination; Methode nouvelle d'etude de l'efficacite des chelateurs de la serie des acides polyamines pour la decontamination interne

Energy Technology Data Exchange (ETDEWEB)

Lafuma, J; Nenot, J C; Morin, M [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1968-07-01

We followed the biological fate of a complex formed on one side with either a rare earth (cerium-144) or a transuranium element (plutonium-239), and on the other side with a chelating agent of the polyamino acid series (EDTA, BAETA, DTPA, TTHA). This method allowed to study: 1 - the in vivo stability of the various complexes and to compare them; 2 - the stability of the complexes as a function of the isotope - chelating agent weight relationships; 3 - the metabolism of the chelating agents resulting in stable complexes, i. e. DTPA and TTHA mainly. This simple method brought out the higher efficiency, of DTPA in chelating rare earths and plutonium and for therapeutic purposes. (authors) [French] La methode consiste a suivre le devenir biologique d'un complexe forme d'une part avec une terre rare (cerium 144) ou un transuranien (plutonium 239) et d'autre part avec un chelateur de la serie des acides polyamines (EDTA, BAETA, DTPA, TTHA). Elle permet d'etudier: 1 - la stabilite in vivo des differents complexes, de les comparer; 2 - la stabilite des complexes en fonction des rapports ponderaux isotope - chelateurs; 3 - le metabolisme des chelateurs formant des complexes stables, essentiellement DTPA et TTHA. Cette methode simple degage la suprematie du DTPA en ce qui concerne la chelation des terres rares et du plutonium, et son utilisation a des fins therapeutiques. (auteurs)

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)

Processes of elimination of activated corrosion products. Chemical decontamination - fuel cleaning

International Nuclear Information System (INIS)

Viala, C.; Brun, C.; Neuhaus, R.; Richier, S.; Bachet, M.

2007-01-01

The abatement of the individual and collective dose of a PWR imposes to control the source term through different processes implemented during the plant exploitation. When the limits of these different optimization processes are reached, the abatement of dose rates requires the implementation of curative processes. The objective is thus to eliminate the contaminated oxides and deposits present on surfaces free of radiation flux, and eventually on surfaces under radiation flux and on the fuel itself. The chemical decontamination of equipments and systems is the main and universal remedy implemented at different levels. On the other hand, the ultrasonic cleaning of fuel assemblies is a promising process. This paper aims at illustrating these different techniques using concrete examples of application in France and abroad (decontamination during steam generator replacement, decontamination of primary pump scroll in hot workshop, decontamination of loop sections, ultrasonic cleaning of fuel). The description of these different operations stresses on their efficiency in terms of dosimetric gain, duration of implementation, generation of wastes, and recontamination following their implementation. (J.S.)

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.

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

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

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.

Application of the chemical properties of ruthenium to decontamination processes; L'application des proprietes chimiques du ruthenium a des procedes de decontamination

Energy Technology Data Exchange (ETDEWEB)

Fontaine, A; Berger, D [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

1965-07-01

The chemical properties of ruthenium in the form of an aqueous solution of the nitrate and of organic tributylphosphate solution are reviewed. From this data, some known examples are given: they demonstrate the processes of separation or of elimination of ruthenium from radioactive waste. (authors) [French] Les proprietes chimiques du ruthenium en solutions aqueuses nitriques et en solutions organiques de tributylphosphate, sont passees en revue. A partir de ces donnees, quelques exemples connus sont cites: ils exposent des procedes de separation ou d'elimination du ruthenium de dechets radioactifs. (auteurs)

Method of chemical decontamination of stainless steel

International Nuclear Information System (INIS)

Onuma, Tsutomu; Akimoto, Hidetoshi.

1989-01-01

The present invention concerns a decontamination method of chemically decontaminating radioactive metal wastes of passivated stainless steels to a radioactivity level identical with usual wastes, in which the amount of oxidizable metal salts used is decreased. Metal wastes of stainless steels contaminated at their surface with radioactive materials are immersed in a sulfuric acid solution. In this case, a voltage is applied for a certain period of time so that the potential of the stainless steels comes to an active region. Then, oxidizable metal salt (tetravalent cerium) is added into the sulfuric acid solution. According to this method, since most of radioactive materials are removed in the immersing step to the sulfuric acid solution, the amount of the tetravalent cerium used is as less as 1/700 and the decontamination time is as short as 1/4 as compared with those in the conventional method. (K.M.)

Decontamination barrier on TMI-2 leadscrew

International Nuclear Information System (INIS)

Baston, V.F.; Hofstetter, K.J.; Bain, G.M.; Haynerg, G.O.

1985-01-01

The first major component removed from the TMI-2 Reactor Vessel that has had extensive analytical examination (i.e. radiochemical, metallography, surface chemical analyses, etc.) is the H-8 leadscrew. These analyses indicate adherent cesium activity that is important to the decontamination efforts for TMI-2

Development of small size wall decontamination robot systems in nuclear power plants

International Nuclear Information System (INIS)

Fujita, Tsuneaki; Takahashi, Tsuyosi

2004-01-01

This paper describes the development of wall decontamination robot systems for nuclear power plants. In nuclear power plants, it is required to reduce maintenance costs, including annual inspection, repairs and so on. Most of such maintenance activities are actually performed after decontamination processes are completed. In particular, the decontamination process of reactor wells is very important for reducing the radiation exposure of human workers. In the past, decontamination of reactor wells used to be done by extra large machine and tools, which caused long working hours and tiresome works. It was one of the reasons maintenance costs couldn't have been easily reduced. There are narrow spaces in the reactor wells that have to be decontaminated by human workers. In order to minimize the radiation exposure to humans, wall decontamination robot systems have been developed. The decontamination robots have rolled brushes and suction mechanisms and are capable of removing contaminants attached to the wall surface of the reactor wells. By making the robots smaller, it is possible to work in narrower spaces. In this paper, the effectiveness of decontamination by the developed robots is shown through experiments in the actual nuclear power plants. (author)

35 Typologie des eaux de surface du bassin du Sebou par multi ...

African Journals Online (AJOL)

PR BOKO

2Service de protection de la qualité de l'eau, Agence du Bassin Hydraulique du ... pour montrer l'évolution de la qualité biologique des eaux de surface du ..... Biological Indicators of Freshwater Pollution and Environmental Management,.

Preconceptual design of the gas-phase decontamination demonstration cart

International Nuclear Information System (INIS)

Munday, E.B.

1993-12-01

Removal of uranium deposits from the interior surfaces of gaseous diffusion equipment will be a major portion of the overall multibillion dollar effort to decontaminate and decommission the gaseous diffusion plants. Long-term low-temperature (LTLT) gas-phase decontamination is being developed at the K-25 Site as an in situ decontamination process that is expected to significantly lower the decontamination costs, reduce worker exposure to radioactive materials, and reduce safeguard concerns. This report documents the preconceptual design of the process equipment that is necessary to conduct a full-scale demonstration of the LTLT method in accordance with the process steps listed above. The process equipment and method proposed in this report are not intended to represent a full-scale production campaign design and operation, since the gas evacuation, gas charging, and off-gas handling systems that would be cost effective in a production campaign are not cost effective for a first-time demonstration. However, the design presented here is expected to be applicable to special decontamination projects beyond the demonstration, which could include the Deposit Recovery Program. The equipment will therefore be sized to a 200 ft size 1 converter (plus a substantial conservative design margin), which is the largest item of interest for gas phase decontamination in the Deposit Recovery Program. The decontamination equipment will allow recovery of the UF 6 , which is generated from the reaction of ClF 3 with the uranium deposits, by use of NaF traps

Innovative ways of decontaminating nuclear facilities

International Nuclear Information System (INIS)

Bremmer, Jan; Gentes, Sascha; Ambos, Frank

2009-01-01

The great variety of surfaces to be decontaminated in a nuclear power plant increases demand for economic solutions and efficient processing systems. The Institute for Technology and Management in Building (TMB) of the University of Karlsruhe (TH) is working on this task in the new professorship of Sascha Gentes and, together with sat Kerntechnik GmbH, developing innovative techniques and tools for surface decontamination. In this effort, sat.Kerntechnik GmbH contributes 50% to the funding of the new professorship at the Karlsruhe Institute of Technology, the merger of the University of Karlsruhe and the Karlsruhe Research Center. The new professorship will extend its work also to various other innovative concepts to be employed not only in demolition but also in maintenance and operation of nuclear facilities. Above and beyond theoretical approaches, practical solutions are in the focus of work. For this reason, new developments are elaborated in close cooperation with the respective users. (orig.)

Decontamination and radioactivity measurement on building surfaces related to dismantling of Japan power demonstration reactor (JPDR)

International Nuclear Information System (INIS)

Hatakeyama, Mutsuo; Tachibana, Mitsuo; Yanagihara, Satoshi

1997-12-01

In the final stage of dismantling activities for decommissioning a nuclear power plant, building structures have to be demolished to release the site for unrestricted use. Since building structures are generally made from massive reinforced concrete materials, it is not a rational way to treat all concrete materials arising from its demolition as radioactive waste. Segregation of radioactive parts from building structures is therefore indispensable. The rational procedures were studied for demolition of building structures by treating arising waste as non-radioactive materials, based on the concept established by Nuclear Safety Commission, then these were implemented in the following way by the JPDR dismantling demonstration project. Areas of the JPDR facilities are categorized into two groups : possibly contaminated areas, and possibly non-contaminated areas, based on the document of the reactor operation. Radioactivity on the building surfaces was then measured to confirm that the qualitative categorization is reasonable. After that, building surfaces were decontaminated in such a way that the contaminated layers were removed with enough margin to separate radioactive parts from non-radioactive building structures. Thought it might be possible to demolish the building structures by treating arising waste as non-radioactive materials, confirmation survey for radioactivity was conducted to show that there is no artificial radioactive nuclides produced by operation in the facility. This report describes the procedures studied on measurement of radioactivity and decontamination, and the results of its implementation in the JPDR dismantling demonstration project. (author)

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)

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)

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

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.

Decontamination and reuse of ORGDP aluminum scrap

International Nuclear Information System (INIS)

Compere, A.L.; Griffith, W.L.; Hayden, H.W.; Wilson, D.F.

1996-12-01

The Gaseous Diffusion Plants, or GDPs, have significant amounts of a number of metals, including nickel, aluminum, copper, and steel. Aluminum was used extensively throughout the GDPs because of its excellent strength to weight ratios and good resistance to corrosion by UF 6 . This report is concerned with the recycle of aluminum stator and rotor blades from axial compressors. Most of the stator and rotor blades were made from 214-X aluminum casting alloy. Used compressor blades were contaminated with uranium both as a result of surface contamination and as an accumulation held in surface-connected voids inside of the blades. A variety of GDP studies were performed to evaluate the amounts of uranium retained in the blades; the volume, area, and location of voids in the blades; and connections between surface defects and voids. Based on experimental data on deposition, uranium content of the blades is 0.3%, or roughly 200 times the value expected from blade surface area. However, this value does correlate with estimated internal surface area and with lengthy deposition times. Based on a literature search, it appears that gaseous decontamination or melt refining using fluxes specific for uranium removal have the potential for removing internal contamination from aluminum blades. A melt refining process was used to recycle blades during the 1950s and 1960s. The process removed roughly one-third of the uranium from the blades. Blade cast from recycled aluminum appeared to perform as well as blades from virgin material. New melt refining and gaseous decontamination processes have been shown to provide substantially better decontamination of pure aluminum. If these techniques can be successfully adapted to treat aluminum 214-X alloy, internal and, possibly, external reuse of aluminum alloys may be possible

Comparison and Evaluation of Various Tritium Decontamination Techniques and Processes

International Nuclear Information System (INIS)

Gentile, C.A.; Langish, S.W.; Skinner, C.H.; Ciebiera, L.P.

2004-01-01

In support of fusion energy development, various techniques and processes have been developed over the past two decades for the removal and decontamination of tritium from a variety of items, surfaces, and components. Tritium decontamination, by chemical, physical, mechanical, or a combination of these methods, is driven by two underlying motivational forces. The first of these motivational forces is safety. Safety is paramount to the established culture associated with fusion energy. The second of these motivational forces is cost. In all aspects, less tritium contamination equals lower operational and disposal costs. This paper will discuss and evaluate the various processes employed for tritium removal and decontamination

Safety analysis report for packaging (onsite) decontaminated equipment self-container

International Nuclear Information System (INIS)

Boehnke, W.M.

1998-01-01

The purpose of this Safety Analysis Report for Packaging (SARP) is to demonstrate that specific decontaminated equipment can be safely used as its own self-container. As a Decontaminated Equipment Self-Container (also referred to as a self-container), no other packaging, such as a burial box, would be required to transport the equipment onsite. The self-container will consist of a piece of equipment or apparatus which has all readily removable interior contamination removed, all of its external openings sealed, and all external surfaces decontaminated to less than 2000 dpm/100 cm for gamma-emitting radionuclides and less than 220 dpm/100 CM2 for alpha-emitting radionuclides

Comparison and Evaluation of Various Tritium Decontamination Techniques and Processes

International Nuclear Information System (INIS)

Gentile, C.A.; Langish, S.W.; Skinner, C.H.; Ciebiera, L.P.

2005-01-01

In support of fusion energy development, various techniques and processes have been developed over the past two decades for the removal and decontamination of tritium from a variety of items, surfaces, and components. The motivational force for tritium decontamination by chemical, physical, mechanical, or a combination of these methods, is driven by two underlying forces. The first of these motivational forces is safety. Safety is paramount to the established culture associated with fusion energy. The second of these motivational forces is cost. In all aspects, less tritium contamination equals lower operational and disposal costs. This paper will discuss and evaluate the various processes employed for tritium removal and decontamination

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)

Decontamination of Steam Generator tube using Abrasive Blasting Technology

International Nuclear Information System (INIS)

Min, B. Y.; Kim, G. N.; Choi, W. K.; Lee, K. W.; Kim, D. H.; Kim, K. H.; Kim, B. T.

2010-01-01

As a part of a technology development of volume reduction and self disposal for large metal waste project, We at KAERI and our Sunkwang Atomic Energy Safety (KAES) subcontractor colleagues are demonstrating radioactively contaminated steam generator tube by abrasive blasting technology at Kori-1 NPP. A steam generator is a crucial component in a PWR (pressurized Water Reactor). It is the crossing between the primary, contaminated, circuit and the secondary waste-steam circuit. The heat from the primary reactor coolant loop is transferred to the secondary side in thousands of small tubes. Due to several problems in the material of those tube, like SCC (Stress Corrosion Cracking), insufficient control in water chemistry, which can be cause of tube leakage, more and more steam generators are replaced today. Only in Korea, already 2 of them are replaced and will be replaced in the near future. The retired 300 ton heavy Steam generator was stored at the storage waste building of Kori NPP site. The steam generator waste has a large volume, so that it is necessary to reduce its volume by decontamination. A waste reduction effect can be obtained through decontamination of the inner surface of a steam generator. Therefore, it is necessary to develop an optimum method for decontamination of the inner surface of bundle tubes. The dry abrasive blasting is a very interesting technology for the realization of three-dimensional microstructures in brittle materials like glass or silicon. Dry abrasive blasting is applicable to most surface materials except those that might be shattered by the abrasive. It is most effective on flat surface and because the abrasive is sprayed and can also applicable on 'hard to reach' areas such as inner tube ceilings or behind equipment. Abrasive decontamination techniques have been applied in several countries, including Belgium, the CIS, France, Germany, Japan, the UK and the USA

Modeling of low temperature plasma for surface and Airborne decontamination

NARCIS (Netherlands)

Mihailova, D.; van Dijk, J.; Hagelaar, G.; Belenguer, P.; Guillot, P.

2014-01-01

This paper aims to study and develop new plasma-based technology for the next generation of molecular decontamination systems. A capacitively coupled plasma is considered for cleaning using the plasma fluxes directed to the walls. The model used for this purpose is the PLASIMO fluid module applied

Proposed draft standard ANS 11.18: recommendations to facilitate decontamination and decommissioning

International Nuclear Information System (INIS)

Jenkins, C.E.; LaGuardia, T.S.; Jones, J.W.

1981-01-01

The purpose of ANS Standard 11.18 is to recommend design guides to facilitate decontamination and eventual decommissioning of a remotely operated radioactive facility. This design guide contains generic recommendations to assist in the planning, selection and arrangement of equipment and materials, and the protection of surfaces to enhance system decontamination and disassembly

Monitoring work at decontamination in Fukushima city

International Nuclear Information System (INIS)

Mori, Kazuyuki

2013-01-01

The author has been working at the decontamination site of Fukushima residences as a radiation monitor since Feb. 2012 for about 1 year, of which experiences are reported here. The decontamination conducted was legally based on the Act on Special Measures concerning the contamination by Fukushima Nuclear Power Plant Accident in Mar. 2011, and on other national, municipal related laws and guidelines. Fukushima city planned to conduct the decontamination for coming 5 years from Oct. 2011 to reduce its ambient dose rate to 9 sites within a residence. The work was managed with monitoring result cards and photographs. The definition of contamination to be cleared was against the dose rate of garden ground surface >30 Bq/cm 2 and of ambient at 1 m height 0.5-2 mc-Sv/h, the latter of which was aimed at reducing to <1 mc-Sv/h and the ambient at 1 cm height, to <0.4 mc-Sv. The ambient dose rate after decontamination of 717 residences has been found decreased to about a half (36-73% of doses before the work). Radiation hazard protection of workers was managed with the health examination defined by the law, education and pocket dosimeter: the exposure dose of the decontamination workers has been found to be about 5 mc-Sv/day. Finally, the report presents comments of thoughts and resolves of the city, executing trader, executer and monitoring staff. (T.T.)

Radiological experience on decontamination of moderator and associated system at NAPS-1

International Nuclear Information System (INIS)

Yadav, C.L.R.; Mitra, S.R.; Pawar, S.K.; Lal Chand

2000-01-01

Narora Atomic Power Station, the first of Indian standardized Pressurized Heavy Water Reactor, is faced with a problem of 60 Co contamination in moderator and its associated system. This contamination has resulted in increase of collective dose contribution. As a part of ALARA campaign in NAPS it was decided to decontaminate the moderator and associated systems and also incorporate modification which will further control the 60 Co contamination. As a part of decontamination program several experiments to determine the effectiveness of the chemical formulation on SS and cupro-nickel surfaces were carried out on various moderator system equipment before finalizing the formulation for full scale decontamination of moderator system. This paper gives an overview of various modifications in system and decontamination efficiency of various chemical formulation which were used for decontamination of moderator system (excluding calandria) and associated equipment. (author)

Application of a novel decontamination process using gaseous ozone

Energy Technology Data Exchange (ETDEWEB)

Moat, J.; Shone, J.; Upton, M. [Manchester Univ., School of Medecine, Manchester (United Kingdom). Medical Microbiology, Translation Medicine; Cargill, J. [Old Medical School, Leeds (United Kingdom). Dept. of Microbiology

2009-08-15

Hospital surfaces that are touched regularly by staff carry bacterial spores and pathogens. Environmental disinfection of health care facilities is an important aspect of infection control. This paper presented a recent innovation aimed at improving hospital hygiene and decontamination of laboratory equipment. The vapour- and gas-based treatment was developed to penetrate rooms or soft furnishings and reach places inaccessible by conventional approaches. Surfaces seeded with a range of vegetative cells and spores of bacteria of clinical relevance were decontaminated using the ozone-based treatment. The efficiency of the approach for room sanitization was also evaluated. A quenching agent was used to rapidly reduce ozone concentrations to safe levels allowing treatment times of less than 1 h for most of the organisms tested. Bacteria was seeded onto agar plates and solid surfaces. Reductions in bacterial load of greater than 3 log values were then recorded for a number of organisms including Escherichia coli and methicillin-resistant Staphylococcus aureus. Application of the process in a 30 m{sup 3} room showed similar reductions in viable counts for these organisms and for Clostridium difficile spores. It was concluded that ozone-based decontamination of healthcare environments could prove to be a highly cost-effective intervention. 35 refs., 1 tab., 3 figs.

Decontamination analysis of the NUWAX-83 accident site using DECON

International Nuclear Information System (INIS)

Tawil, J.J.

1983-11-01

This report presents an analysis of the site restoration options for the NUWAX-83 site, at which an exercise was conducted involving a simulated nuclear weapons accident. This analysis was performed using a computer program deveoped by Pacific Northwest Laboratory. The computer program, called DECON, was designed to assist personnel engaged in the planning of decontamination activities. The many features of DECON that are used in this report demonstrate its potential usefulness as a site restoration planning tool. Strategies that are analyzed with DECON include: (1) employing a Quick-Vac option, under which selected surfaces are vacuumed before they can be rained on; (2) protecting surfaces against precipitation; (3) prohibiting specific operations on selected surfaces; (4) requiring specific methods to be used on selected surfaces; (5) evaluating the trade-off between cleanup standards and decontamination costs; and (6) varying of the cleanup standards according to expected exposure to surface

Training of skin decontamination and its results

International Nuclear Information System (INIS)

Yasunaka, Hideo; Wadachi, Yoshiki.

1976-01-01

In the nuclear power and radioisotope handling facilities, one of the most important problems is a radioactive contamination on skin. Hand skin contamination occurs very often in the operation area and such surface contamination must be removed as soon as possible to prevent an internal contamination. From 1967 to 1975, training courses for skin decontamination had been held with total 536 of trainee based on the radiation protection manual at the Oarai Research Establishment of JAERI. In the training courses, fresh pig skin samples used instead of human skin were contaminated with 137 Cs, 131 I, 85 Sr, 60 Co, 144 Ce, 88 Y, 239 Pu, fission products and activated metal corrosion particles, respectively. These samples were washed practically by each trainee with the skin decontamination method recommended in the manual. Results obtained in the training showed that such training itself is a significant work and this skin decontamination method is an excellent first aid. (auth.)

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

Polysaccharide-thickened aqueous fluoride solutions for rapid destruction of the nerve agent VX. Introducing the opportunity for extensive decontamination scenarios.

Science.gov (United States)

Elias, Shlomi; Saphier, Sigal; Columbus, Ishay; Zafrani, Yossi

2014-01-01

Among the chemical warfare agents, the extremely toxic nerve agent VX (O-ethyl S-2-(diisopropylamino)ethyl methylphosphonothioate) is a target of high importance in the development of decontamination methods, due to its indefinite persistence on common environmental surfaces. Liquid decontaminants are mostly characterized by high corrosivity, usually offer poor coverage, and tend to flow and accumulate in low areas. Therefore, the development of a noncorrosive decontaminant, sufficiently viscous to resist dripping from the contaminated surface, is necessary. In the present paper we studied different polysaccharides-thickened fluoride aqueous solutions as noncorrosive decontaminants for rapid and efficient VX degradation to the nontoxic product EMPA (ethyl methylphosphonic acid). Polysaccharides are environmentally benign, natural, and inexpensive. Other known decontaminants cannot be thickened by polysaccharides, due to the sensitivity of the latter toward basic or oxidizing agents. We found that the efficiency of VX degradation in these viscous solutions in terms of kinetics and product identity is similar to that of KF aqueous solutions. Guar gum (1.5 wt %) with 4 wt % KF was chosen for further evaluation. The benign nature, rheological properties, adhering capabilities to different surfaces, and decontamination from a porous matrix were examined. This formulation showed promising properties for implementation as a spray decontaminant for common and sensitive environmental surfaces.

Waste Volume Reduction Using Surface Characterization and Decontamination By Laser Ablation

International Nuclear Information System (INIS)

Pellin, Michael J.; Savina, Michael R.; Reed, Claude B.; Zhiyue, Xu; Yong, Wang

2000-01-01

The U.S. Department of Energy's nuclear complex, a nation-wide system of facilities for research and production of nuclear materials and weapons, contains large amounts of radioactively contaminated concrete[1]. This material must be disposed of prior to the decommissioning of the various sites. Often the radioactive contaminants in concrete occupy only the surface and near-surface (∼3-6 mm deep) regions of the material. Since many of the structures such as walls and floors are 30 cm or more thick, it makes environmental and economic sense to try to remove and store only the thin contaminated layer rather than to treat the entire structure as waste. Current mechanical removal methods, known as scabbling, are slow and labor intensive, suffer from dust control problems, and expose workers to radiation fields. Improved removal methods are thus in demand[2-5]. Prior to decontamination, the surface must be characterized to determine the types and amounts of contaminants present i n order to decide on an appropriate cleaning strategy. Contamination occurs via exposure to air and water-borne radionuclides and by neutron activation. The radionuclides of greatest concern are (in order of abundance) [1]: 137Cs and 134Cs, 238U, 60Co, and 90Sr, followed by 3H, radioactive iodine, and a variety of Eu isotopes and transuranics. A system capable of on- line analysis is valuable since operators can determine the type of contaminants in real time and make more efficient use of costly sampling and characterization techniques. Likewise, the removed waste itself must be analyzed to insure that proper storage and monitoring techniques are used. The chemical speciation of radionuclides in concrete is largely unknown. Concrete is a complex material comprising many distinct chemical and physical phases on a variety of size scales[6-8]. Most studies of radionuclides in cements and concrete are for the most part restricted to phenomenological treatments of diffusion of ion s, particularly

Dresses problems arising from hot-plant operation and their solution (1961); Les problemes vestimentaires poses par l'exploitation des installations actives et leurs solutions (1961)

Energy Technology Data Exchange (ETDEWEB)

Rodier, J.; Bouzigues, H.; Boutot, P. [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

1961-07-01

This article deals with effective methods to struggle radioactive contamination using rationally designed working clothes. The choice of the cloth is important and cotton, because of its absorbent properties constitutes an effective barrier to radioelements failing on its surface. Clothing the personnel of large nuclear industrial concerns is a big problem which can only be solved by carefully studied methods. The decontamination and washing of large amounts of clothes whose flow increases during periods of radio-active incidents have to be treated as are those operations in hospital laundering. Linen washing by the German counter-current method (the Sulzman system) is of great value because of the volume which can be treated and, more important, because of the small amount of liquid waste produced. Dry cleaning is certainly a method of the future and is even more economic than the preceding one. In 'active' laundries, the control of clothing for residual contamination can constitute a serious bottleneck in the production of clean clothing if automatic high-speed machines are not used. The risk to the operating personnel comes solely from contamination of the atmosphere and of the surfaces. Because of this, the plant must be considered as an active zone in which are handled several tens of millicuries of dangerous emitters and several micro- curies of plutonium daily. (authors) [French] Ce memoire traite des moyens efficaces de lutte contre la contamination radioactive que peuvent offrir des vetements de travail de conception rationnelle. Le choix du tissu est un element important et la fibre de coton, par ses proprietes absorbantes, constitue un excellent barrage aux radioelements deposes a sa surface. L'habillement du personnel des grands ensembles industriels de l'energie atomique est un gros probleme qui ne peut etre solutionne qu'avec des moyens soigneusement etudies. La decontamination et le lavage des grandes quantites de vetements

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.

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

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

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

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

Modelling Adsorption of Foam-Forming Surfactants on Heterogeneous Surfaces Using the Surface Excess Formalism Conception de modèle pour l'adsorption des agents tensio-actifs moussants sur des surfaces hétérogènes en faisant appel au formalisme de l'excès de surface

Directory of Open Access Journals (Sweden)

Mannhardt K.

2006-11-01

Full Text Available Adsorption at the solid/liquid interface is detrimental to most enhanced oil recovery processes that make use of surfactants. This paper describes several extensions to a previously described surface excess model of adsorption in flow through porous media [7, 8]. It is shown that two parameters of the model, the monolayer coverages of surfactant and water, can be determined independently, thus reducing the number of adjustable parameters in the model from six to four. Experimental evidence suggests that the selectivity, previously assumed constant, should be a function of concentration. A functional form of selectivity that is derived from thermodynamic principles is incorporated into the model. Finally, adsorption on heterogeneous surfaces is discussed, and a simple form of surface heterogeneity (a bimodal distribution of selectivities is incorporated into the model and its benefits in determining adsorption isotherms from core flood data are demonstrated. L'adsorption à l'interface solide/liquide nuit aux procédés de RAH qui utilisent des tensio-actifs. Pour la réussite de ces procédés, il est par conséquent impératif de connaître les niveaux d'adsorption et de bien en comprendre les mécanismes. Le modèle qui fait appel au concept d'excès de surface pour décrire l'adsorption dans les écoulements traversant un milieu poreux a été décrit dans des articles précédents et a été utilisé pour évaluer l'adsorption d'un certain nombre d'agents tensioactifs moussants [7,8]. Le présent article étudie trois développements de ce modèle. Le modèle d'adsorption comporte un ensemble de paramètres ajustables qui sont utilisés pour faire correspondre les concentrations d'effluents simulées et expérimentales lors d'une injection en milieu poreux. Ces paramètres peuvent ensuite être utilisés pour calculer les isothermes d'adsorption de certains systèmes. Deux des paramètres du modèle, les revêtements monocouche de

Decontamination technology verification test on scraping surface soil on the highway roadside slopes using unmanned scraping machine

International Nuclear Information System (INIS)

Fujinaka, Hiroyuki; Kubota, Mitsuru; Shibuya, Susumu; Kasai, Yoshimitsu

2013-01-01

The restore the normal life in the contaminated area, reconstruction of the infrastructure is necessary and early decontamination of roads and roadside slopes of highway are required. Decontamination work of roadside slopes is conducted only by hand working so far, but on the high and steep roadside slopes it is desirable to carry out decontamination work by an unmanned scraping machine to reduce working hours and improve safety. In this verification test, decontamination work of the roadside slope of highway, of which area was 20m W x 15m L and divided into two sections, was implemented by the machine or by hand, and working hours and radiation exposure dose were measured. As the results of the test, working hours and radiation exposure dose by the machine were 49% and 63% respectively compared to those by hand. Based on the results, cost and radiation dose for decontamination work on larger slopes were evaluated. Cost by the machine is estimated to be less than that by hand where the area is over 4,000m 2 . It is confirmed that the decontamination work of roadside slopes by the machine can be done more quickly and safely in comparison with hand working. (author)

Optimized laser system for decontamination of painted surfaces

International Nuclear Information System (INIS)

Champonnois, F.; Lascoutouna, C.; Long, H.; Thro, P.Y.; Mauchien, P.

2010-01-01

Laser systems have long been seen as potentially very interesting for removing contamination from surfaces. The main expected advantages are the possibility of remote process and the absence of secondary waste. However these systems were unable to find their way to an industrial deployment due to the lack of reliability of the laser and the difficulty to satisfactory collect the (contaminated) ablated matter. In this contribution we report on a compact, reliable and efficient laser decontaminating system called ASPILASERO. It is adapted to the constraints bound to a nuclear environment. It takes advantages of the recent progress made by the fibre lasers which have now a lifetime longer than 20000 hours without maintenance. The collecting system collects all the removed matter (gases and aerosols) on nuclear grade filters. The fully automated system has been successfully tested on a vertical wall of a stopped nuclear installation. It has demonstrated an efficiency of 1 m 2 /hr which is in the same order of other classical techniques but with a much lower quantity of waste and the ability to work continuously without human intervention. Measurements performed after the laser treatment have shown that the contamination was completely removed by removing the paint and that this contamination was not re-deposited elsewhere on the wall. The system will also be used in highly contaminated hot cells to decrease the radiation and allow maintenance or refurbishing in safe working conditions. (authors)

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

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

New method for studying the efficiency of chelating agents of the polyamine acid series for internal decontamination; Methode nouvelle d'etude de l'efficacite des chelateurs de la serie des acides polyamines pour la decontamination interne

Energy Technology Data Exchange (ETDEWEB)

Lafuma, J.; Nenot, J.C.; Morin, M. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1968-07-01

We followed the biological fate of a complex formed on one side with either a rare earth (cerium-144) or a transuranium element (plutonium-239), and on the other side with a chelating agent of the polyamino acid series (EDTA, BAETA, DTPA, TTHA). This method allowed to study: 1 - the in vivo stability of the various complexes and to compare them; 2 - the stability of the complexes as a function of the isotope - chelating agent weight relationships; 3 - the metabolism of the chelating agents resulting in stable complexes, i. e. DTPA and TTHA mainly. This simple method brought out the higher efficiency, of DTPA in chelating rare earths and plutonium and for therapeutic purposes. (authors) [French] La methode consiste a suivre le devenir biologique d'un complexe forme d'une part avec une terre rare (cerium 144) ou un transuranien (plutonium 239) et d'autre part avec un chelateur de la serie des acides polyamines (EDTA, BAETA, DTPA, TTHA). Elle permet d'etudier: 1 - la stabilite in vivo des differents complexes, de les comparer; 2 - la stabilite des complexes en fonction des rapports ponderaux isotope - chelateurs; 3 - le metabolisme des chelateurs formant des complexes stables, essentiellement DTPA et TTHA. Cette methode simple degage la suprematie du DTPA en ce qui concerne la chelation des terres rares et du plutonium, et son utilisation a des fins therapeutiques. (auteurs)

Application of the chemical properties of ruthenium to decontamination processes; L'application des proprietes chimiques du ruthenium a des procedes de decontamination

Energy Technology Data Exchange (ETDEWEB)

Fontaine, A.; Berger, D. [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

1965-07-01

The chemical properties of ruthenium in the form of an aqueous solution of the nitrate and of organic tributylphosphate solution are reviewed. From this data, some known examples are given: they demonstrate the processes of separation or of elimination of ruthenium from radioactive waste. (authors) [French] Les proprietes chimiques du ruthenium en solutions aqueuses nitriques et en solutions organiques de tributylphosphate, sont passees en revue. A partir de ces donnees, quelques exemples connus sont cites: ils exposent des procedes de separation ou d'elimination du ruthenium de dechets radioactifs. (auteurs)

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

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.)

Processing radioactive effluents with ion-exchanging resins: study of result extrapolation; Traitement des effluents radioactifs par resines echangeuses d'ions: etude de l'extrapolation des resultats

Energy Technology Data Exchange (ETDEWEB)

Wormser, G.

1960-05-03

As a previous study showed the ion-exchanging resins could be used in Saclay for the treatment of radioactive effluents, the author reports a study which aimed at investigating to which extent thus obtained results could be extrapolated to the case of higher industrial columns. The author reports experiments which aimed at determining extrapolation modes which could be used for columns of organic resin used for radioactive effluent decontamination. He notably studied whether the Hiester and Vermeulen extrapolation law could be applied. Experiments are performed at constant percolation flow rate, at varying flow rate, and at constant flow rate [French] Plusieurs etudes ont ete faites dans le but d'examiner les possibilites d'emploi des resines echangeuses d'ions pour le traitement des effluents radioactifs. Dans un rapport preliminaire, nous avons montre dans quelles limites un tel procede pouvait etre utilise au Centre d'Etudes Nucleaires de Saclay. Les essais ont ete effectues sur des petites colonnes de resine au laboratoire; il est apparu ensuite necessaire de prevoir dans quelle mesure les resultats ainsi obtenus peuvent etre extrapoles a des colonnes industrielles, de plus grande hauteur. Les experiences dont les resultats sont exposes dans ce rapport, ont pour but de determiner les modes d'extrapolation qui pourraient etre employes pour des colonnes de resine organique utilisees pour la decontamination d'effluents radioactifs. Nous avons en particulier recherche si la loi d'extrapolation de Hiester et Vermeulen qui donne de bons resultats dans le cas de fixation d'ions radioactifs en presence d'un ion macrocomposant sur des terres, pouvait etre appliquee. Les experiences, en nombre limite, ont montre que la loi d'extrapolation de Hiester et Vermeulen pouvait s'appliquer dans le cas de l'effluent considere quand les debits de percolation sont tres faibles; quand ils sont plus forts, les volumes de liquide percoles, a fixation egale, sont proportionnels aux

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.)

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)

Off-site consequences of radiological accidents: methods, costs and schedules for decontamination

International Nuclear Information System (INIS)

Tawil, J.J.; Bold, F.C.; Harrer, B.J.; Currie, J.W.

1985-08-01

This report documents a data base and a computer program for conducting a decontamination analysis of a large, radiologically contaminated area. The data base, which was compiled largely through interviews with knowledgeable persons both in the public and private sectors, consists of the costs, physical inputs, rates and contaminant removal efficiencies of a large number of decontamination procedures. The computer program utilizes this data base along with information specific to the contaminated site to provide detailed information that includes the least costly method for effectively decontaminating each surface at the site, various types of property losses associated with the contamination, the time at which each subarea within the site should be decontaminated to minimize these property losses, the quantity of various types of labor and equipment necessary to complete the decontamination, dose to radiation workers, the costs for surveying and monitoring activities, and the disposal costs associated with radiological waste generated during cleanup. The program and data base are demonstrated with a decontamination analysis of a hypothetical site. 39 refs., 24 figs., 155 tabs

Off-site consequences of radiological accidents: methods, costs and schedules for decontamination

Energy Technology Data Exchange (ETDEWEB)

Tawil, J.J.; Bold, F.C.; Harrer, B.J.; Currie, J.W.

1985-08-01

This report documents a data base and a computer program for conducting a decontamination analysis of a large, radiologically contaminated area. The data base, which was compiled largely through interviews with knowledgeable persons both in the public and private sectors, consists of the costs, physical inputs, rates and contaminant removal efficiencies of a large number of decontamination procedures. The computer program utilizes this data base along with information specific to the contaminated site to provide detailed information that includes the least costly method for effectively decontaminating each surface at the site, various types of property losses associated with the contamination, the time at which each subarea within the site should be decontaminated to minimize these property losses, the quantity of various types of labor and equipment necessary to complete the decontamination, dose to radiation workers, the costs for surveying and monitoring activities, and the disposal costs associated with radiological waste generated during cleanup. The program and data base are demonstrated with a decontamination analysis of a hypothetical site. 39 refs., 24 figs., 155 tabs.

Efficacy of scalp hair decontamination following exposure to vapours of sulphur mustard simulants 2-chloroethyl ethyl sulphide and methyl salicylate

OpenAIRE

Spiandore , Marie; Piram , Anne; Lacoste , Alexandre; Prevost , P.; Maloni , Pascal; TORRE , Franck; Asia , L.; Josse , D.; Doumenq , Pierre

2017-01-01

International audience; Chemical warfare agents are an actual threat and victims' decontamination is a main concern when mass exposure occurs. Skin decontamination with current protocols has been widely documented, as well as surface decontamination. However, considering hair ability to trap chemicals in vapour phase, we investigated hair decontamination after exposure to sulphur mustard simulants methyl salicylate and 2-chloroethyl ethyl sulphide. Four decontamination protocols were tested o...

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

Decontamination of 2-chloroethyl ethylsulfide using titanate nanoscrolls

Science.gov (United States)

Kleinhammes, Alfred; Wagner, George W.; Kulkarni, Harsha; Jia, Yuanyuan; Zhang, Qi; Qin, Lu-Chang; Wu, Yue

2005-08-01

Titanate nanoscrolls, a recently discovered variant of TiO 2 nanocrystals, are tested as reactive sorbent for chemical warfare agent (CWA) decontamination. The large surface area of the uncapped tubules provides the desired rapid absorption of the contaminant while water molecules, intrinsic constituents of titanate nanoscrolls, provide the necessary chemistry for hydrolytic reaction. In this study the decomposition of 2-chloroethyl ethylsulfide (CEES), a simulant for the CWA mustard, was monitored using 13C NMR. The NMR spectra reveal reaction products as expected from the hydrolysis of CEES. This demonstrates that titanate nanoscrolls could potentially be employed as a decontaminant for CWAs.

Contaminant Organic Complexes: Their Structure and Energetics in Surface Decontamination Processes

International Nuclear Information System (INIS)

Satish C. B. Myneni

2005-01-01

Siderophores are biological macromolecules (400-2000 Da) released by bacteria in iron limiting situations to sequester Fe from iron oxyhydroxides and silicates in the natural environment. These molecules contain hydroxamate and phenolate functional groups, and exhibit very high affinity for Fe 3+ . While several studies were conducted to understand the behavior of siderophores and their application to the metal sequestration and mineral dissolution, only a few of them have examined the molecular structure of siderophores and their interactions with metals and mineral surfaces in aqueous solutions. Improved understanding of the chemical state of different functional moieties in siderophores can assist in the application of these biological molecules in actinide separation, sequestration and decontamination processes. The focus of our research group is to evaluate the (a) functional group chemistry of selected siderophores and their metal complexes in aqueous solutions, and (b) the nature of siderophore interactions at the mineral-water interfaces. We selected desferrioxamine B (desB), a hydroxamate siderophore, and its small structural analogue, acetohydroxamic acid (aHa), for this investigation. We examined the functional group chemistry of these molecules as a function of pH, and their complexation with aqueous and solid phase Fe(III). For solid phase Fe, we synthesized all naturally occurring Fe(III)-oxyhydroxides (goethite, lepidocrocite, akaganeite, feroxyhite) and hematite. We also synthesized Fe-oxides (goethite and hematite) of different sizes to evaluate the influence of particle size on mineral dissolution kinetics. We used a series of molecular techniques to explore the functional group chemistry of these molecules and their complexes. Infrared spectroscopy is used to specifically identify the variations in oxime group as a function of pH and Fe(III) complexation. Resonance Raman spectroscopy was used to evaluate the nature of hydroxamate binding in the

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)

Sterilization and decontamination of surfaces using atmospheric pressure plasma discharges

Energy Technology Data Exchange (ETDEWEB)

Garate, E.; Gornostaeva, O.; Alexeff, I.; Kang, W.L.

1999-07-01

The goal of the program is to demonstrate that an atmospheric pressure plasma discharge can rapidly and effectively sterilize or decontaminate surfaces that are contaminated with model biological and chemical warfare agents. The plasma is produced by corona discharge from an array of pins and a ground plane. The array is constructed so that various gases, like argon or helium, can be flowed past the pins where the discharge is initiated. The pin array can be biased using either DC. AC or pulsed discharges. the work done to date has focused on the sterilization of aluminum, polished steel and tantalum foil metal coupons, about 2 cm on a side and 2 mm thick, which have been inoculated with up to 10{sup 6} spores per coupon of Bacillus subtilis var niger or Bascillus stearothermorphilus. Results indicate that 5 minute exposures to the atmospheric pressure plasma discharge can reduce the viable spore count by 4 orders of magnitude. The atmospheric pressure discharge is also effective in decomposing organic phosphate compounds that are stimulants for chemical warfare agents. Details of the decomposition chemistry, by-product formation, and electrical energy consumption of the system will be discussed.

Processing of wastewaters of column bases of the C.E.B. uranium-thorianite plant; Traitement des eaux residuaires des pieds de colonne de l'usine d'urano-thorianite du C.E.B.

Energy Technology Data Exchange (ETDEWEB)

Cohen, P.; Wormser, G.

1959-08-12

The authors report, on the one hand, results of tests aimed at determining an optimal chemical treatment for the purification of wastewaters from the column of extraction by solvents of the CEB uranium-thorianite plant, and on the other hand, the measurement problems faced due to the chemical composition of the studied solutions. In a first set of tests, the authors studied the carryover efficiency of barium sulphate and barium carbonate, but due to difficulties created by the presence of barium when recovering radium, other possibilities have been studied which take this possibility of barium recovery without barium into account. The obtained results show the benefit of an intermediate filtration of lead sulphate, followed by an additional purification. The decontamination rate is then multiplied by ten, and radium is recovered in a precipitate free of hydroxides. An operational mode is proposed. In the first part, the authors describe measurement methods used to determine total alpha and radium in highly salted solutions [French] Dans ce rapport sont exposes: - d'une part les resultats des essais de laboratoire en vue de determiner un traitement chimique optimum pour l'epuration des eaux residuaires en provenance de la colonne d'extraction par solvants de l'usine d'urano-thorianite du C.E.B.; - d'autre part les problemes de mesure qui se sont poses du fait de la composition chimique des solutions etudiees. Dans une premiere serie d'essais nous avons etudie l'efficacite de l'entrainement par le sulfate de baryum et le carbonate de baryum. Toutefois, avertis des difficultes posees par la presence de baryum lors d'une eventuelle recuperation du radium, nous avons ete amenes a etudier les deux cas suivants qui tiennent compte de la necessite de recuperer le radium sans baryum: - soit faire une seule filtration d'un precipite de sulfate de plomb + hydroxydes, - soit proceder a une filtration intermediaire du sulfate de plomb. Apres divers essais, il est apparu que la

Mesoporous titanium-manganese dioxide for sulphur mustard and soman decontamination

International Nuclear Information System (INIS)

Stengl, Vaclav; Bludska, Jana; Oplustil, Frantisek; Nemec, Tomas

2011-01-01

Highlights: → New nano-dispersive materials for warfare agents decontamination. → 95% decontamination activities for sulphur mustard. → New materials base on titanium and manganese oxides. -- Abstract: Titanium(IV)-manganese(IV) nano-dispersed oxides were prepared by a homogeneous hydrolysis of potassium permanganate and titanium(IV) oxo-sulphate with 2-chloroacetamide. Synthesised samples were characterised using Brunauer-Emmett-Teller (BET) surface area and Barrett-Joiner-Halenda porosity (BJH), X-ray diffraction (XRD), infrared spectroscopy (IR), and scanning electron microscopy (SEM). These oxides were taken for an experimental evaluation of their reactivity with sulphur mustard (HD or bis(2-chloroethyl)sulphide) and soman (GD or (3,3'-dimethylbutan-2-yl)-methylphosphonofluoridate). Mn 4+ content affects the decontamination activity; with increasing Mn 4+ content the activity increases for sulphur mustard and decreases for soman. The best decontamination activities for sulphur mustard and soman were observed for samples TiMn 3 7 with 18.6 wt.% Mn and TiMn 5 with 2.1 wt.% Mn, respectively.

Innovative decontamination technology by abrasion in vibratory vessels

International Nuclear Information System (INIS)

Fabbri, Silvio; Ilarri, Sergio

2007-01-01

Available in abstract form only. Full text of publication follows: The possibility of using conventional vibratory vessel technology as a decontamination technique is the motivation for the development of this project. The objective is to explore the feasibility of applying the vibratory vessel technology for decontamination of radioactively-contaminated materials such as pipes and metal structures. The research and development of this technology was granted by the U.S. Department of Energy (DOE). Abrasion processes in vibratory vessels are widely used in the manufacture of metals, ceramics, and plastics. Samples to be treated, solid abrasive media and liquid media are set up into a vessel. Erosion results from the repeated impact of the abrasive particles on the surface of the body being treated. A liquid media, generally detergents or surfactants aid the abrasive action. The amount of material removed increases with the time of treatment. The design and construction of the machine were provided by Vibro, Argentina private company. Tests with radioactively-contaminated aluminum tubes and a stainless steel bar, were performed at laboratory level. Tests showed that it is possible to clean both the external and the internal surface of contaminated tubes. Results show a decontamination factor around 10 after the first 30 minutes of the cleaning time. (authors)

Decontamination of stainless steel using cerium(IV): Material recycle and reuse

International Nuclear Information System (INIS)

Kurath, D.E.; Bray, L.A.; Jarrett, J.H.

1997-01-01

It has been demonstrated that the Cerium(IV) process can effectively remove radioactive contamination from stainless steel. Ce(IV) is a powerful oxidizing agent that is applied in an inorganic acid solution or as an atomized spray by injection into steam directed at the contaminated surface. Ce(IV) attacks the oxide layer and underlying metal surface to remove a 0.5-μm to 3-μm layer. This process has been implemented in a number of actual operations. In one application, a Ce(IV) steam decontamination process was instrumental in renovating hot cells at the High-Level Radiochemistry Facility (325-A building) at the Hanford site. The initial dose rate of approximately 100,000 mR/h was reduced to <50 mR/h and allowed manned entry during hot cell renovation activities. These valuable facilities have been returned to full operation. In an application at the West Valley Nuclear Services Co., Inc., the surfaces of stainless steel canisters that had been filled with vitrified high-level waste have been decontaminated. In some cases the free release levels for surface contamination have been achieved. In another application, five plutonium contaminated stainless steel vessels were decontaminated during decommissioning of the Critical Mass Facility at Hanford

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.

Electrochemical decontamination of Pu contaminated stainless steel

International Nuclear Information System (INIS)

Turner, A.D.; Pottinger, J.S.; Junkison, A.R.

1983-08-01

Electrochemical decontamination has been demonstrated to be very effective in removing plutonium nitrate contamination (0.5 μg cm -2 ) on stainless steels. The amount of metal dissolved to achieve a DF of 10 2 to 10 3 was 2 to 7 μm depending on the electrolyte used. In unstirred electrolytes 1M HNO 3 , 1M HNO 3 /0.1M NaF, 5M HNO 3 perform best. Under stirred electrolyte conditions, there is a general marginal fall in effectiveness except for 5M HNO 3 where there is a slight improvement. The optimum performance is a compromise between maximizing the electrolyte throwing power and minimizing substrate surface roughening during decontamination. (author)

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

Finding radiation hot-spots for a private residence/decontamination manual

International Nuclear Information System (INIS)

Nishizawa, Kunihide

2012-01-01

Since the Fukushima Daiichi Nuclear Power Station accident, the radio-iodine and cesium analysis group of ad hoc committee of safety measures has investigated initial screening monitor of the soils and examined contamination and experienced decontamination works. Existence of hot-spots where Cs 137 is concentrated is confirmed. The report makes a manual to find such a hot-spot in a private residence and how the decontamination should be carried out. Particularly, the report provides the definite examples of hot-spots, for instances, a roof, an eaves trough (a gutter), a side drain (a ditch), dead leaves (withered grass), surface land, a wood block, etc. and how the decontamination should be confirmed and the dusts be collected and kept. (S. Ohno)

Effect of HNO3-cerium(IV) decontamination on stainless steel canister materials

International Nuclear Information System (INIS)

Westerman, R.E.; Mackey, D.B.

1991-01-01

Stainless steel canisters will be filled with vitrified radioactive waste at the West Valley Demonstration Project (WVDP), West Valley, NY. After they are filled, the sealed canisters will be decontaminated by immersion in a HNO 3 -Ce(IV) solution, which will remove the oxide film and a small amount of metal from the surface of the canisters. Studies were undertaken in support of waste form qualification activities to determine the effect of this decontamination treatment on the legibility of the weld-bead canister identification label, and to determine whether this decontamination treatment could induce stress-corrosion cracking (SCC) in the AISI 304L stainless steel (SS) canister material. Neither the label legibility nor the canister integrity with regard to SCC were found to be prejudiced by the simulated decontamination treatment

Binding affinity and decontamination of dermal decontamination gel to model chemical warfare agent simulants.

Science.gov (United States)

Cao, Yachao; Elmahdy, Akram; Zhu, Hanjiang; Hui, Xiaoying; Maibach, Howard

2018-05-01

Six chemical warfare agent simulants (trimethyl phosphate, dimethyl adipate, 2-chloroethyl methyl sulfide, diethyl adipate, chloroethyl phenyl sulfide and diethyl sebacate) were studied in in vitro human skin to explore relationship between dermal penetration/absorption and the mechanisms of simulant partitioning between stratum corneum (SC) and water as well as between dermal decontamination gel (DDGel) and water. Both binding affinity to and decontamination of simulants using DDGel were studied. Partition coefficients of six simulants between SC and water (Log P SC/w ) and between DDGel and water (Log P DDGel/w ) were determined. Results showed that DDGel has a similar or higher binding affinity to each simulant compared to SC. The relationship between Log P octanol/water and Log P SC/w as well as between Log P octanol/water and Log P DDGel/w demonstrated that partition coefficient of simulants correlated to their lipophilicity or hydrophilicity. Decontamination efficiency results with DDGel for these simulants were consistent with binding affinity results. Amounts of percentage dose of chemicals in DDGel of trimethyl phosphate, dimethyl adipate, 2-chloroethyl methyl sulfide, diethyl adipate, chloroethyl phenyl sulfide and diethyl sebacate were determined to be 61.15, 85.67, 75.91, 53.53, 89.89 and 76.58, with corresponding amounts absorbed in skin of 0.96, 0.65, 1.68, 0.72, 0.57 and 1.38, respectively. In vitro skin decontamination experiments coupled with a dermal absorption study demonstrated that DDGel can efficiently remove chemicals from skin surface, back-extract from the SC, and significantly reduced chemical penetration into skin or systemic absorption for all six simulants tested. Therefore, DDGel offers a great potential as a NextGen skin Decon platform technology for both military and civilian use. Copyright © 2018 John Wiley & Sons, Ltd.

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)

Development of CDE (calculation system for decontamination effect) for the support of decontamination to restore the environment. Software visually depicting the effect of decontamination Work

International Nuclear Information System (INIS)

Satoh, Daiki

2012-01-01

CDE in the title developed by Japan Atomic Energy Agency (JAEA) is explained for its use to support the cleaning work of the environment contaminated by the Fukushima Daiichi Nuclear Power Plant Accident (Mar. 11, 2011). With this CDE software (available at http://nsed.jaea.go.jp/josen, from Nov. 2, 2011), the effect of decontamination schedule/work can be evaluable rapidly and accurately by calculating the ambient dose rates before and after the work. Access number to the CDE site until Jan., 2012, amounts to 402, for the purposes of ambient dose assessment (20%), planning of decontamination (15%), study/investigation (15%), etc. The system software is operable in Microsoft Excel with Graphical User Interface (GUI) described by VBA (Visual Basic for Applications). To be inputted in CDE are the map of the region subjected to decontamination, data of surface contamination density and of decontamination coefficients for the area relief, all of which are available through the internet and actual measurement, which is then followed by output as tables and figures of distribution of the ambient dose rate before and after the work, and of the rate reduction coefficient. Radiation subjected to calculation is from radiocesium ( 134 Cs and 137 Cs). When the software is compared for its accuracy with those by previous software Particle and Heavy Ion Transport Code System (PHITS) and by actual measurement, their results all show a virtually satisfactory agreement, and the time necessary for calculation is over several-ten hours in PHITS, and within about 10 seconds, in CDE. Updated information of CDE is available at the above mentioned site and twitter.com/JAEA_nsed. (T.T.)

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

Decontamination Technologies, Task 3, Urban Remediation and Response Project

International Nuclear Information System (INIS)

Heiser, J.; Sullivan, T.

2009-01-01

In the aftermath of a Radiological Dispersal Device (RDD, also known as a dirty bomb) it will be necessary to remediate the site including building exteriors and interiors, equipment, pavement, vehicles, personal items etc. Remediation will remove or reduce radioactive contamination from the area using a combination of removing and disposing of many assets (including possible demolition of buildings), decontaminating and returning to service other assets, and fixing in place or leaving in place contamination that is deemed 'acceptable'. The later will require setting acceptable dose standards, which will require negotiation with all involved parties and a balance of risk and cost to benefit. To accomplish the first two, disposal or decontamination, a combination of technologies will be deployed that can be loosely classified as: Decontamination; Equipment removal and size reduction; and Demolition. This report will deal only with the decontamination technologies that will be used to return assets to service or to reduce waste disposal. It will not discuss demolition, size reduction or removal technologies or equipment (e.g., backhoe mounted rams, rock splitter, paving breakers and chipping hammers, etc.). As defined by the DOE (1994), decontamination is removal of radiological contamination from the surfaces of facilities and equipment. Expertise in this field comes primarily from the operation and decommissioning of DOE and commercial nuclear facilities as well as a small amount of ongoing research and development closely related to RDD decontamination. Information related to decontamination of fields, buildings, and public spaces resulting from the Goiania and Chernobyl incidents were also reviewed and provide some meaningful insight into decontamination at major urban areas. In order to proceed with decontamination, the item being processed needs to have an intrinsic value that exceeds the cost of the cleaning and justifies the exposure of any workers during the

Decontamination Technologies, Task 3, Urban Remediation and Response Project

Energy Technology Data Exchange (ETDEWEB)

Heiser,J.; Sullivan, T.

2009-06-30

In the aftermath of a Radiological Dispersal Device (RDD, also known as a dirty bomb) it will be necessary to remediate the site including building exteriors and interiors, equipment, pavement, vehicles, personal items etc. Remediation will remove or reduce radioactive contamination from the area using a combination of removing and disposing of many assets (including possible demolition of buildings), decontaminating and returning to service other assets, and fixing in place or leaving in place contamination that is deemed 'acceptable'. The later will require setting acceptable dose standards, which will require negotiation with all involved parties and a balance of risk and cost to benefit. To accomplish the first two, disposal or decontamination, a combination of technologies will be deployed that can be loosely classified as: Decontamination; Equipment removal and size reduction; and Demolition. This report will deal only with the decontamination technologies that will be used to return assets to service or to reduce waste disposal. It will not discuss demolition, size reduction or removal technologies or equipment (e.g., backhoe mounted rams, rock splitter, paving breakers and chipping hammers, etc.). As defined by the DOE (1994), decontamination is removal of radiological contamination from the surfaces of facilities and equipment. Expertise in this field comes primarily from the operation and decommissioning of DOE and commercial nuclear facilities as well as a small amount of ongoing research and development closely related to RDD decontamination. Information related to decontamination of fields, buildings, and public spaces resulting from the Goiania and Chernobyl incidents were also reviewed and provide some meaningful insight into decontamination at major urban areas. In order to proceed with decontamination, the item being processed needs to have an intrinsic value that exceeds the cost of the cleaning and justifies the exposure of any workers

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)

Application of epifluorescence scanning for monitoring the efficacy of protein removal by RF gas-plasma decontamination

Energy Technology Data Exchange (ETDEWEB)

Baxter, Helen C; Richardson, Patricia R; Campbell, Gaynor A; Jones, Anita C; Baxter, Robert L [School of Chemistry, Joseph Black Chemistry Building, University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ (United Kingdom); Kovalev, Valeri I; Maier, Robert; Barton, James S [School of Engineering and Physical Science, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); DeLarge, Greg [Plasma Etch Inc, 3522 Arrowhead Drive, Carson City, NV 89706 (United States); Casey, Mark [Sterile Services Department, Royal Infirmary of Edinburgh, Edinburgh EH16 4AS (United Kingdom)], E-mail: r.baxter@ed.ac.uk

2009-11-15

The development of methods for measuring the efficiency of gas-plasma decontamination has lagged far behind application. An approach to measuring the efficiency of protein removal from solid surfaces using fluorescein-labelled bovine serum albumin and epifluorescence scanning (EFSCAN) is described. A method for fluorescently labelling proteins, which are adsorbed and denatured on metal surfaces, has been developed. Both approaches have been used to evaluate the efficiency of radio frequency (RF) gas-plasma decontamination protocols. Examples with 'real' surgical instruments demonstrate that an argon-oxygen RF gas-plasma treatment can routinely reduce the protein load by about three orders of magnitude beyond that achieved by current decontamination methods.

Application of epifluorescence scanning for monitoring the efficacy of protein removal by RF gas-plasma decontamination

International Nuclear Information System (INIS)

Baxter, Helen C; Richardson, Patricia R; Campbell, Gaynor A; Jones, Anita C; Baxter, Robert L; Kovalev, Valeri I; Maier, Robert; Barton, James S; DeLarge, Greg; Casey, Mark

2009-01-01

The development of methods for measuring the efficiency of gas-plasma decontamination has lagged far behind application. An approach to measuring the efficiency of protein removal from solid surfaces using fluorescein-labelled bovine serum albumin and epifluorescence scanning (EFSCAN) is described. A method for fluorescently labelling proteins, which are adsorbed and denatured on metal surfaces, has been developed. Both approaches have been used to evaluate the efficiency of radio frequency (RF) gas-plasma decontamination protocols. Examples with 'real' surgical instruments demonstrate that an argon-oxygen RF gas-plasma treatment can routinely reduce the protein load by about three orders of magnitude beyond that achieved by current decontamination methods.

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

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

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

Decontamination of the product handling area at the West Valley Demonstration Project: Final topical report for period July 1985 to February 1986

International Nuclear Information System (INIS)

Phillips, E.C.

1986-06-01

The purpose of this report is to describe the decontamination and decommissioning (D and D) preparations of an existing facility at the West Valley Demonstration Project (WVDP), the Product Handling Area (PHA), to be part of a Liquid Waste Treatment System (LWTS) in conjunction with the Cement Solidification System (CSS). Two interconnected facilities, the Uranium Product Cell (UPC) and the Uranium Loadout Area (ULO), form the PHA. Both of these facilities contain large tanks. Both of the tanks in the UPC are suitable for use as components of the LWTS. In addition, the UPC is the only existing means of access to the bottom of the Product Purification Cell (PPC) in which some of the equipment for the LWTS will be installed. Consequently, this report describes the decontamination of the PHA from a radioactively contaminated environment to one which may be entered in street clothes. Of the two facilities of the PHA, the UPC was the more highly contaminated prior to decontamination. Decontamination of the UPC has been completed leaving most of the surfaces in the facility smearably clean. Decontamination of the UPC consisted of washing all surfaces, draining the floor sump, removing unneeded piping, installing a back flow filter system, painting all surfaces, installing rubber matting on the floor and placing new stainless steel covering on the UPC ledge. Decontamination operations in the ULO have been completed and were similar to those in the UPC consisting of decontaminating by hand wipedown, removing contamination fixed in paint, and applying new paint. In addition, two pumps and a concrete pump niche were removed. Prior to decontamination, surface contamination was present in the ULO. After decontamination, most of the surfaces in the ULO were clean of smearable contamination. D and D Operations were initiated in the PHA in July 1985 and completed in February 1986. 13 figs., 9 tabs

Industrial Hygiene Concerns during the Decontamination and Decommissioning of the Tokamak Fusion Test Reactor

CERN Document Server

Lumia, M E

2002-01-01

A significant industrial hygiene concern during the Decontamination and Decommissioning (D and D) of the Tokamak Fusion Test Reactor (TFTR) was the oxidation of the lead bricks' surface, which were utilized for radiation shielding. This presented both airborne exposure and surface contamination issues for the workers in the field removing this material. This paper will detail the various protection and control methods tested and implemented to protect the workers, including those technologies deployed to decontaminate the work surfaces. In addition, those techniques employed to recycle the lead for additional use at the site will be discussed.

Industrial Hygiene Concerns during the Decontamination and Decommissioning of the Tokamak Fusion Test Reactor

International Nuclear Information System (INIS)

M.E. Lumia; C.A. Gentile

2002-01-01

A significant industrial hygiene concern during the Decontamination and Decommissioning (D and D) of the Tokamak Fusion Test Reactor (TFTR) was the oxidation of the lead bricks' surface, which were utilized for radiation shielding. This presented both airborne exposure and surface contamination issues for the workers in the field removing this material. This paper will detail the various protection and control methods tested and implemented to protect the workers, including those technologies deployed to decontaminate the work surfaces. In addition, those techniques employed to recycle the lead for additional use at the site will be discussed

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

also influenced the degradation rate since the degradation of VX was significantly faster when the NMR analysis was performed in the organic solvent acetonitrile compared to water. In conclusion, we have applied the in vitro flow-through diffusion cell for evaluation of skin decontamination procedures of human epidermis exposed to OPCs. It was demonstrated that early decontamination is crucial for efficient mitigation of epidermal penetration of VX and that almost complete removal of the nerve agent from the skin surface is possible. Our data also indicate that the pH of RSDL together with the solubility of OPC in RSDL are of primary importance for the decontamination efficacy. Copyright © 2017 Elsevier B.V. All rights reserved.

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

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

A fast-sorting measurement technique to determine decontamination priority

International Nuclear Information System (INIS)

Distenfeld, C.H.; Brosey, B.; Igarashi, H.

1988-01-01

Recovery of large contaminated buildings, such as the Three Mile Island Unit 2 (TMI-2) reactor building, are complicated by ceilings that can be 12 to 13 m high. Much of the overhead space is filled with conduits, pipes, cable trays, ventilation ducts, and steel structures. The total complex surface can greatly exceed the total surface of walls and floors. Concrete pedestals, heavy steel stands, embedded steel rails, refueling mechanisms, and other similar structures complicate normally accessible areas and impede exposure reduction efforts. Initial recovery of contaminated spaces tends to involve treatment of hot spots and accessible spaces such as floor and wall surfaces. Subsequent decontamination may be less efficient since untreated surfaces, such as in overhead spaces, may be beyond the reach of ordinary decontamination tools. To conserve radiation exposure of recovery personnel, it is important to prioritize the effort so that early work provides maximum exposure reduction. Subsequent exposure reduction can then be carried out with less total exposure to recovery personnel. This favorable scenario depends on identification of key surfaces that most affect the exposure rate. The quick-sort method that was developed is based on the Eberline HP 220A directional survey system

Decontamination of chemical warfare sulfur mustard agent simulant by ZnO nanoparticles

Science.gov (United States)

Sadeghi, Meysam; Yekta, Sina; Ghaedi, Hamed

2016-07-01

In this study, zinc oxide nanoparticles (ZnO NPs) have been surveyed to decontaminate the chloroethyl phenyl sulfide as a sulfur mustard agent simulant. Prior to the reaction, ZnO NPs were successfully prepared through sol-gel method in the absence and presence of polyvinyl alcohol (PVA). PVA was utilized as a capping agent to control the agglomeration of the nanoparticles. The formation, morphology, elemental component, and crystalline size of nanoscale ZnO were certified and characterized by SEM/EDX, XRD, and FT-IR techniques. The decontamination (adsorption and destruction) was tracked by the GC-FID analysis, in which the effects of polarity of the media, such as isopropanol, acetone and n-hexane, reaction time intervals from 1 up to 18 h, and different temperatures, including 25, 35, 45, and 55 °C, on the catalytic/decontaminative capability of the surface of ZnO NPs/PVA were investigated and discussed, respectively. Results demonstrated that maximum decontamination (100 %) occurred in n-hexane solvent at 55 °C after 1 h. On the other hand, the obtained results for the acetone and isopropanol solvents were lower than expected. GC-MS chromatograms confirmed the formation of hydroxyl ethyl phenyl sulfide and phenyl vinyl sulfide as the destruction reaction products. Furthermore, these chromatograms proved the role of hydrolysis and elimination mechanisms on the catalyst considering its surface Bronsted and Lewis acid sites. A non-polar solvent aids material transfer to the reactive surface acid sites without blocking these sites.

Correlation Study of Magnetite Dissolution in Hybrid Decontamination Process

Energy Technology Data Exchange (ETDEWEB)

Kim, Seon-Byeong; Won, Hui-Jun; Park, Jung-Sun; Park, Sang-Yoon; Moon, Jei-Kwon; Choi, Wang-Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

In the operating plants, the localized corrosion on SG tubes which are transporters of thermal energy to the secondary side lowers the reduction heat transfer efficiency as well as degrades the lifetime of SG. Magnetite, Fe3O4, is a commonly found corrosion product on the inner surface of reactor coolant system. Simply magnetite can be reduced to hematite, Fe{sub 2}O{sub 3}, and further to iron when oxygen is limited or ample reducing agents are supplied. Along this line, number of decontamination processes has been developed since 1970s and most of them contain organic acid and additive chelating agents. However, many reports have pointed out the negative environmental effect of those chemicals, and currently there are new approaches to overcome the limited decontamination efficiency and large volume of secondary waste from other alternate processes without using such those organic chemicals. In present study, we investigated the magnetite dissolution in HyBRID solution as newly developing decontamination process. As a preliminary study for empirical modeling of decontamination by HyBRID solution, simply correlation study between variable and magnetite dissolution was introduced with studied mechanism and experimental results.

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)

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

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...

Melting decontamination and recycling of radioactive polluted metals from uranium mining and metallurgy

International Nuclear Information System (INIS)

Chen Anquan

2011-01-01

Melting method is a primary method used for decontamination of radioactive polluted metal from uranium mining and metallurgy. The decontamination mechanism of the method, the way selection and its features are introduced. Taking the ten year's work of CNNC Uranium Mining and Metallurgy Radioactive Polluted Metal Melting Processing Center as example, the effects of processing radioactive polluted metals by smelting method are discussed. The surface pollution levels of radioactive polluted metal from uranium mining and metallurgy decreased from 4-48 Bq/cm 2 before decontamination to 0.004-0.016 Bq/cm 2 after decontamination, and the specific activity of its metal is less than 1 Bq/g, which is below the solution control level proposed by IAEARS-G1.7 'the application of the concepts of exclusion, immunity and solution control'. The metals after decontamination can be recycled by producing tooth plate and bucket teeth of excavator used in mines. (authors)

Mesoporous titanium-manganese dioxide for sulphur mustard and soman decontamination

Energy Technology Data Exchange (ETDEWEB)

Stengl, Vaclav, E-mail: stengl@iic.cas.cz [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR v.v.i., 250 68 Rez (Czech Republic); Bludska, Jana [Department of Solid State Chemistry, Institute of Inorganic Chemistry AS CR v.v.i., 250 68 Rez (Czech Republic); Oplustil, Frantisek; Nemec, Tomas [Military Technical Institute of Protection Brno, Veslarska 230, 628 00 Brno (Czech Republic)

2011-11-15

Highlights: {yields} New nano-dispersive materials for warfare agents decontamination. {yields} 95% decontamination activities for sulphur mustard. {yields} New materials base on titanium and manganese oxides. -- Abstract: Titanium(IV)-manganese(IV) nano-dispersed oxides were prepared by a homogeneous hydrolysis of potassium permanganate and titanium(IV) oxo-sulphate with 2-chloroacetamide. Synthesised samples were characterised using Brunauer-Emmett-Teller (BET) surface area and Barrett-Joiner-Halenda porosity (BJH), X-ray diffraction (XRD), infrared spectroscopy (IR), and scanning electron microscopy (SEM). These oxides were taken for an experimental evaluation of their reactivity with sulphur mustard (HD or bis(2-chloroethyl)sulphide) and soman (GD or (3,3'-dimethylbutan-2-yl)-methylphosphonofluoridate). Mn{sup 4+} content affects the decontamination activity; with increasing Mn{sup 4+} content the activity increases for sulphur mustard and decreases for soman. The best decontamination activities for sulphur mustard and soman were observed for samples TiMn{sub 3}7 with 18.6 wt.% Mn and TiMn{sub 5} with 2.1 wt.% Mn, respectively.

Radiation protection at the RA Reactor in 1985, Part -4, decontamination and treatment of solid radioactive materials for the needs of RA reactor

International Nuclear Information System (INIS)

Plecas, I.; Vukovic, Z.; Blagojevic, R.; Kostadinovic, A.

1985-01-01

This report describes the activity of the decontamination and treatment team for the needs of the RA reactor, its equipment, working conditions, methods for decontamination, means of decontamination, type and quantity of decontaminated surfaces, number of decontaminated objects, quantity of collected radioactive solid wastes, their packaging, transport to the storage place and topography od radiation field in the storage during 1985 [sr

324 and 325 Building hot cell cleanout program: Decontamination of C-Cell

International Nuclear Information System (INIS)

Katayama, Y.B.; Holton, L.K. Jr.

1989-10-01

During FY 1989 the decontamination of C-Cell of Hanford's 324 Building was completed as part of the 324 and 325 Building Hot Cell Cleanout Program sponsored by the DOE Nuclear Energy's Surplus Facilities Management Program. The decontamination effort was completed using a series of remote and contact decontamination techniques. Initial radiation readings in C-Cell averaged 50 rad/hr and were reduced remotely to less than 200 mrad/hr using an alkaline foam cleaner followed by a 5000-psi water flush. Contact decontamination was then permissible using ultra high-pressure water, at 36,000 psi, further reducing the average radiation level in the cell to less than 86 mrem/hr. The approach used in decontaminating C-Cell resulted in a savings in radiation exposure of 87% and a cost savings of 39% compared to a hands-on procedure used in A-Cell, 324 Building in 1987. The radiation dose and the costs to achieve a 244-fold reduction in radiation contamination were 1.65 mrem per ft 2 and $96 per ft 2 of cell surface area. 14 figs., 4 tabs

Decontamination Project for Cell G of the Metal Recovery Facility at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Mandry, G.J.; Grisham, R.W.

1994-02-01

The goal of the decontamination effort in Cell G at the Metal Recovery Facility, Building 3505, located at the Oak Ridge National Laboratory, was two-fold: to determine the effectiveness of the dry decontamination technique employed and to provide data required to assess whether additional decontamination using this method would be beneficial in the eventual decommissioning of the facility. Allied Technology Group (ATG) was contracted to remove a portion of the concrete surface in Cell G by a technique known as scabbling. Some metallic cell components were also scabbled to remove paint and other surface debris. Generally, the scabbling operation was a success. Levels of contamination were greatly reduced. The depth of contaminant penetration into the concrete surfaces of certain areas was much greater than had been anticipated, necessitating the removal of additional concrete and extending ATG's period of performance. Scabbling and other related techniques will be extremely useful in the decontamination and decommissioning of other nuclear facilities with similar radiological profiles

DECISION ANALYSIS AND TECHNOLOGY ASSESSMENTS FOR METAL AND MASONRY DECONTAMINATION TECHNOLOGIES

International Nuclear Information System (INIS)

Ebadian, M.A.

1999-01-01

The purpose of this investigation was to conduct a comparative analysis of innovative technologies for the non-aggressive removal of coatings from metal and masonry surfaces and the aggressive removal of one-quarter to one-inch thickness of surface from structural masonry. The technologies tested should be capable of being used in nuclear facilities. Innovative decontamination technologies are being evaluated under standard, non-nuclear conditions at the FIU-HCET technology assessment site in Miami, Florida. This study is being performed to support the OST, the Deactivation and Decommissioning (D and D) Focus Area, and the environmental restoration of DOE facilities throughout the DOE complex by providing objective evaluations of currently available decontamination technologies

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

EM Task 12 - Laser cleaning of Contaminated Painted Surfaces

International Nuclear Information System (INIS)

Ames A. Grisanti; Charlene R. Crocker; Robert J. Jensen

1998-01-01

Several techniques are available or under development for surface decontamination in nuclear facilities. Each technique has its merits; however, none of them is universally the best choice for all surface decontamination applications. Because of the multitude of factors which influence the environmental and economic aspects of selecting a surface decontamination technique, it is difficult to select the best method in a given situation; an objective basis for comparing techniques is needed. The objective of this project is to develop a software tool for use by personnel selecting a surface decontamination technique. The software will incorporate performance data for available surface decontamination techniques. The beta release of the Surface Decontamination Assistant Software has been completed and has undergone testing at the Energy and Environmental Research Center (EERC). Minor modifications to the software will be completed before the end of November 1998, and a final release of the software will be issued

EM Task 12 - Laser cleaning of contaminated painted surfaces

International Nuclear Information System (INIS)

Grisanti, Ames A.; Crocker, Charlene R.; Jensen, Robert R.

1999-01-01

Several techniques are available or under development for surface decontamination in nuclear facilities. Each technique has its merits; however, none of them is universally the best choice for all surface decontamination applications. Because of the multitude of factors which influence the environmental and economic aspects of selecting a surface decontamination technique, it is difficult to select the best method in a given situation; an objective basis for comparing techniques is needed. The objective of this project was to develop a software tool for use by personnel selecting a surface decontamination technique. The software incorporates performance data for available surface decontamination techniques. The beta release version of the Surface Decontamination Assistant Software has been completed and has undergone testing at the Energy and Environmental Research Center. Minor modifications to the software were completed, and a final release version of the software is ready to be issued

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)

Method for electrolytic decontamination of radioactive contaminated metals

International Nuclear Information System (INIS)

Tanaka, Akio; Horita, Masami; Onuma, Tsutomu; Kato, Koji

1991-01-01

The invention relates to an electrolytic decontamination method for radioactive contaminated metals. The contaminated sections are eluted by electrolysis after the surface of a piece of equipment used with radioactive substances has been immersed in an electrolyte. Metal contaminated by radioactive substances acts as the anode

Decontamination of B. globigii spores from drinking water infrastructure using disinfectants

Data.gov (United States)

U.S. Environmental Protection Agency — Decontamination of Bacillus spores adhered to common drinking water infrastructure surfaces was evaluated using a variety of disinfectants. Corroded iron and...

Hairy skin exposure to VX in vitro: effectiveness of delayed decontamination.

Science.gov (United States)

Rolland, P; Bolzinger, M-A; Cruz, C; Josse, D; Briançon, S

2013-02-01

The chemical warfare agents such as VX represent a threat for both military and civilians, which involves an immediate need of effective decontamination systems. Since human scalp is usually unprotected compared to other body regions covered with clothes, it could be a preferential site of exposure in case of terrorist acts. The purpose of this study was to determine if skin decontamination could be efficient when performed more than 1h after exposure. In addition, the impact of hairs in skin contamination was investigated. By using in vitro skin models, we demonstrated that about 75% of the applied quantity of VX was recovered on the skin surface 2h after skin exposition, which means that it is worth decontaminating even if contamination occurred 2h before. The stratum corneum reservoir for VX was quickly established and persistent. In addition, the presence of hairs modified the percutaneous penetration of the nerve agent by binding of VX to hairs. Hair shaft has thus to be taken into account in the decontamination process. Reactive Skin Decontamination Lotion (RSDL) and Fuller's Earth (FE) were active in the skin decontamination 45min post-exposure, but RSDL was more efficient in reducing the amount of VX either in the skin or in the hair. Copyright © 2012 Elsevier Ltd. All rights reserved.

Nanocrystalline zinc oxide for the decontamination of sarin

Energy Technology Data Exchange (ETDEWEB)

Mahato, T.H. [Defense R and D Establishment, Jhansi Road, 474002, Gwalior, MP (India); Prasad, G.K., E-mail: gkprasad@lycos.com [Defense R and D Establishment, Jhansi Road, 474002, Gwalior, MP (India); Singh, Beer; Acharya, J.; Srivastava, A.R.; Vijayaraghavan, R. [Defense R and D Establishment, Jhansi Road, 474002, Gwalior, MP (India)

2009-06-15

Nanocrystalline zinc oxide materials were prepared by sol-gel method and were characterized by X-ray diffraction, scanning electron microscopy, thermogravimetry, nitrogen adsorption and infrared spectroscopy techniques. The data confirmed the formation of zinc oxide materials of zincite phase with an average crystallite size of {approx}55 nm. Obtained material was tested as destructive adsorbent for the decontamination of sarin and the reaction was followed by GC-NPD and GC-MS techniques. The reaction products were characterized by GC-MS and the data explored the role of hydrolysis reaction in the detoxification of sarin. Sarin was hydrolyzed to form surface bound non-toxic phosphonate on the surface of nano-zinc oxide. The data also revealed the values of rate constant and half-life to be 4.12 h{sup -1} and 0.16 h in the initial stages of the reaction and 0.361 h{sup -1} and 1.9 h at the final stages of the reaction for the decontamination reaction on nanocrystalline ZnO.

Nanocrystalline zinc oxide for the decontamination of sarin

International Nuclear Information System (INIS)

Mahato, T.H.; Prasad, G.K.; Singh, Beer; Acharya, J.; Srivastava, A.R.; Vijayaraghavan, R.

2009-01-01

Nanocrystalline zinc oxide materials were prepared by sol-gel method and were characterized by X-ray diffraction, scanning electron microscopy, thermogravimetry, nitrogen adsorption and infrared spectroscopy techniques. The data confirmed the formation of zinc oxide materials of zincite phase with an average crystallite size of ∼55 nm. Obtained material was tested as destructive adsorbent for the decontamination of sarin and the reaction was followed by GC-NPD and GC-MS techniques. The reaction products were characterized by GC-MS and the data explored the role of hydrolysis reaction in the detoxification of sarin. Sarin was hydrolyzed to form surface bound non-toxic phosphonate on the surface of nano-zinc oxide. The data also revealed the values of rate constant and half-life to be 4.12 h -1 and 0.16 h in the initial stages of the reaction and 0.361 h -1 and 1.9 h at the final stages of the reaction for the decontamination reaction on nanocrystalline ZnO.

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

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)

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)

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

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 )

Biophysical Evaluation of Food Decontamination Effects on Tissue and Bacteria

DEFF Research Database (Denmark)

Andersen, Ann Zahle; Duelund, Lars; Brewer, Jonathan

2011-01-01

Traditionally, the effects and efficiency of food surface decontamination processes, such as chlorine washing, radiation, or heating, have been evaluated by sensoric analysis and colony-forming unit (CFU) counts of surface swabs or carcass rinses. These methods suffice when determining probable...... consumer responses or meeting legislative contamination limits. However, in the often very costly, optimization process of a new method, more quantitative and unbiased results are invaluable. In this study, we employed a biophysical approach for the investigation of qualitative and quantitative changes...... that there are no contradictions between data obtained by either approach. However, the biophysical methods draw a much more nuanced picture of the effects and efficiency of the investigated decontamination method, revealing, e.g., an exponential dose/response relationship between SonoSteam® treatment time and changes in collagen...

Decontamination by shotblasting of radioactivity deposited on an asphalt road

International Nuclear Information System (INIS)

Warming, L.

1987-01-01

Long-lived fission products may be deposited in the environment after a serious reactor accident. From previous experiments it is known that if firehosing is to be used for decontamination it has to be done soon after the deposition. It is therefore worthwhile to study another decontamination method. An experimental study has been conducted of how well shotblasting can remove contamination from an asphalt road. In shotblasting a thin layer of the surface is loosened by the impact of small steel balls, and in the same procedure the surface dust is vacuumed up and the steel balls recovered. The contaminant was 86 Rb, which behaves as caesium. As reference, the weathering of identical contamination on an asphalt road, a concrete road and a road covered with small concrete stones was studied concurrently. (author)

Decontamination efficiency of detergents on the market for the skin contaminated with radioactive materials. The comparative test (1)

International Nuclear Information System (INIS)

Miyabe, Kenjiro; Ninomiya, Kazushi; Takasaki, Koji; Horiuchi, Nobuharu; Yasunaka, Hideo; Izumi, Yuichi

1999-04-01

Contamination incidence on human body and skin happens sometimes during radiation works in controlled area. The radioactive surface contamination should be removed from the skin as soon as possible for radiation control and exposure management. Titanium oxide paste, which is reserved as a detergent for decontamination, has a satisfactory and reliable result for decontamination effects. The titanium oxide paste, however, has a short preservation period, and must be updated and supplied every serenal months. Decontamination tests for about 60 kinds of detergents on the market were carried out with swine and radioactive material, Ce-144. Radioactive solution of Ce-144 was dropped on the test samples of swine skin, which were left for 5 min or 40 min as it is. Radioactivities of the samples were measured before and after washing by the detergents. As a result of the decontamination tests, 22 kinds of detergents on the market which have a similar decontamination efficiency to the titanium oxide paste were selected. It was also ascertained that the decontamination efficiency of all the detergents decreased on the test samples which were immersed in the radioactive solution for 40 min and wounded on skin surface. (Suetake, M.)

Assessment of strippable coatings for decontamination and decommissioning

International Nuclear Information System (INIS)

Ebadian, M.A.

1998-01-01

Strippable or temporary coatings were developed to assist in the decontamination of the Three Mile Island (TMI-2) reactor. These coatings have become a viable option during the decontamination and decommissioning (D and D) of both US Department of Energy (DOE) and commercial nuclear facilities to remove or fix loose contamination on both vertical and horizontal surfaces. A variety of strippable coatings are available to D and D professionals. However, these products exhibit a wide range of performance criteria and uses. The Hemispheric Center for Environmental Technology (HCET) at Florida International University (FIU) was commissioned to perform a 2-year investigation into strippable coatings. This investigation was divided into four parts: (1) identification of commercially available strippable coating products; (2) survey of D and D professionals to determine current uses of these coatings and performance criteria; (3) design and implementation of a non-radiological testing program to evaluate the physical properties of these coatings; and (4) design and implementation of a radiological testing program to determine decontamination factors and effects of exposure to ionizing radiation. Activities during fiscal year 1997 are described

Zirconium Hydroxide-coated Nanofiber Mats for Nerve Agent Decontamination.

Science.gov (United States)

Kim, Sohee; Ying, Wu Bin; Jung, Hyunsook; Ryu, Sam Gon; Lee, Bumjae; Lee, Kyung Jin

2017-03-16

Diverse innovative fabrics with specific functionalities have been developed for requirements such as self-decontamination of chemical/biological pollutants and toxic nerve agents. In this work, Zr(OH) 4 -coated nylon-6,6 nanofiber mats were fabricated for the decontamination of nerve agents. Nylon-6,6 fabric was prepared via the electrospinning process, followed by coating with Zr(OH) 4 , which was obtained by the hydrolysis of Zr(OBu) 4 by a sol-gel reaction on nanofiber surfaces. The reaction conditions were optimized by varying the amounts of Zr(OBu) 4 ,the reaction time, and the temperature of the sol-gel reaction. The composite nanofibers show high decontamination efficiency against diisopropylfluorophosphate, which is a nerve agent analogue, due to its high nucleophilicity that aids in the catalysis of the hydrolysis of the phosphonate ester bonds. Composite nanofiber mats have a large potential and can be applied in specific fields such as military and medical markets. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

A study on decontamination of TRU, Co, and Mo using plasma surface etching technique

International Nuclear Information System (INIS)

Seo, Y.D.; Kim, Y.S.; Paek, S.H.; Lee, K.H.; Jung, C.H.; Oh, W.Z.

2001-01-01

Recently dry decontamination/surface-cleaning technology using plasma etching has been focused in the nuclear industry. In this study, the applicability and the effectiveness of this new dry processing technique are experimentally investigated by examining the etching reaction of UO 2 , Co, and Mo in r.f. plasma with the etchant gas of CF 4 /O 2 mixture. UO 2 is chosen as a representing material for uranium and TRU (TRans-Uranic) compounds and metallic Co and Mo are selected because they are the principal contaminants in the spent nuclear components such as valves and pipes made of stainless steel or INCONEL. Results show that in all cases maximum etching rate is achieved when the mole fraction of O 2 to CF 4 /O 2 mixture gas is 20 %, regardless of temperature and r.f. power. (author)

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

Bioterrorism poses a real threat to the public health and national security, and the restoration of affected facilities after a chemical, biological or radiological attack is a major concern. This paper reviewed aspects of a project conducted to collect information, test and validate procedures for site restoration after a terrorist attack. The project began with a review of existing technology and then examined new technologies. Restoration included pickup, neutralization, decontamination, removal and final destruction and deposition of contaminants as well as cleaning and neutralization of material and contaminated waste from decontamination. The project was also intended to test existing concepts and develop new ideas. Laboratory scale experiments consisted of testing, using standard laboratory techniques. Radiation decontamination consisted of removal and concentration of the radioisotopes from removal fluid. General restoration guidelines were provided, as well as details of factors considered important in specific applications, including growth conditions and phases of microorganisms in biological decontamination, or the presence of inhibitors or scavengers in chemical decontamination. Various agents were proposed that were considered to have broad spectrum capability. Test surrogates for anthrax were discussed. The feasibility of enhanced oxidation processes was examined in relation to the destruction of organophosphorus, organochlorine and carbamate pesticides. The goal was to identify a process for the treatment of surfaces contaminated with pesticides. Tests included removal from carpet, porous ceiling tile, steel plates, and floor tiles. General radiation contamination procedures and techniques were reviewed, as well as radiological decontamination waste treatment. It was concluded that there is no single decontamination technique applicable for all contaminants, and decontamination methods depend on economic, social and health factors. The amount of

Efficacy of scalp hair decontamination following exposure to vapours of sulphur mustard simulants 2-chloroethyl ethyl sulphide and methyl salicylate.

Science.gov (United States)

Spiandore, Marie; Piram, Anne; Lacoste, Alexandre; Prevost, Philippe; Maloni, Pascal; Torre, Franck; Asia, Laurence; Josse, Denis; Doumenq, Pierre

2017-04-01

Chemical warfare agents are an actual threat and victims' decontamination is a main concern when mass exposure occurs. Skin decontamination with current protocols has been widely documented, as well as surface decontamination. However, considering hair ability to trap chemicals in vapour phase, we investigated hair decontamination after exposure to sulphur mustard simulants methyl salicylate and 2-chloroethyl ethyl sulphide. Four decontamination protocols were tested on hair, combining showering and emergency decontamination (use of Fuller's earth or Reactive Skin Decontamination Lotion RSDL ® ). Both simulants were recovered from hair after treatment, but contents were significantly reduced (42-85% content allowance). Showering alone was the least efficient protocol. Concerning 2-chloroethyl ethyl sulphide, protocols did not display significant differences in decontamination efficacy. For MeS, use of emergency decontaminants significantly increased showering efficacy (10-20% rise), underlining their usefulness before thorough decontamination. Our results highlighted the need to extensively decontaminate hair after chemical exposure. Residual amounts after decontamination are challenging, as their release from hair could lead to health issues. Copyright © 2016. Published by Elsevier B.V.

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.

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

Situations of decontamination promotion activities. Efforts by Tokyo Electric Power Company, Fukushima Revitalization Headquarters, Decontamination Promotion Office

International Nuclear Information System (INIS)

Takano, Takahiko; Ito, Kei; Takizawa, Koichi

2015-01-01

As for the decontamination of the soil contaminated with radioactive materials, decontamination is on the way in compliance with the 'Act on Special Measures Concerning the Handling of Environmental Pollution by Radioactive Materials by the NPS Accident Associated with the Tohoku District - Off the Pacific Ocean' (hereinafter, the Act on Special Measures). Tokyo Electric Power Company (TEPCO), as the party concerned to the accident, is cooperating with decontamination activities conducted by countries and municipalities under the Act on Special Measures. Total number of people cooperated by the Decontamination Promotion Office amounts to about 120,000 people. The cooperation to the decontamination by countries and municipalities covers the following fields: provision of knowledge of radiation, training of site management and supervisors, and proposal such as the decontamination method suitable for the site. As cooperation to various monitoring, there is a traveling monitoring that performs radiation measurement from the vehicles. As cooperation in the farming and industrial resumption toward the reconstruction, the group has implemented support for the distribution promotion of the holdup that was stuck in distribution due to contamination with radioactive substances. As decontamination related technology, the following are performed: (1) preparation of radiation understanding promotion tool, (2) development of precise individual dose measurement technology, and (3) development and utilization of decontamination effect analysis program. In the future, this group will perform the follow-up for decontamination, and measures toward the lifting of evacuation order. It will install the basis to perform various technical analyses on decontamination, and will further intensify technical cooperation. (A.O.)

Effect of decontamination on oxidation of austenitic stainless steel in reactor conditions

International Nuclear Information System (INIS)

Starkman, T.

1984-07-01

Austenitic stainless steels were oxidized in static autoclaves in light water reactor conditions. After the autoclave treatments the specimens were decontaminated with the aid of alkaline potassium permanganate (AP) and oxalic and citric acid (CITROX) as well as electrochemically in H 3 PO 4 . Alternating oxidation and decontamination tests were performed. An elemental analysis of the surfaces of the specimens was carried out by electron spectroscopy. Changes in structures and thicknesses of the oxide layers were observed. (author)

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

Electropolishing as a decontamination process: progress and applications

International Nuclear Information System (INIS)

Allen, R.P.; Arrowsmith, H.W.; Charlot, L.A.; Hooper, J.L.

1978-04-01

Research studies demonstrated the ability of electropolishing to reduce the radiation levels of steel tools and stainless steel vacuum system components, which were heavily contaminated with plutonium oxide, from 1 million dis/min x 100 cm 2 to background in less than 10 min. Other examples of objects that have been decontaminated within minutes using electropolishing include hot cell manipulator assemblies, analytical instrument components, laboratory transfer containers, offsite shipping containers, fission product storage capsules, laboratory animal cages, and nuclear reactor process tube components. One of the major activities of this research has been the establishment and intensive operation of a 400-gal immersion electropolishing system. Progress has also been made in developing in situ electropolishing techniques that can be used to decontaminate metallic surfaces that cannot readily be transported to or immersed in a conventional electropolishing tank. Sectioning/pretreatment studies are under way to develop and demonstrate optimum disassembly, sectioning, surface preparation, and gross contamination removal procedures. Arc saw, plasma arc torch, and explosive cutting techniques are being evaluated in terms of the thickness and characteristics of the disturbed metal layer. Some of the pretreatment methods under consideration for removal of paint, grease, corrosion layers, and gross contamination include vibratory finishing, ultrasonics, dry and liquid abrasive blasting, and high-pressure spray systems. Other supporting studies are also in progress to provide a sound technical basis for scale-up and widespread application of this new decontamination process. 44 figures

Behavior of sulfur mustard in sand, concrete, and asphalt matrices: Evaporation, degradation, and decontamination.

Science.gov (United States)

Jung, Hyunsook; Choi, Seungki

2017-10-15

The evaporation, degradation, and decontamination of sulfur mustard on environmental matrices including sand, concrete, and asphalt are described. A specially designed wind tunnel and thermal desorber in combination with gas chromatograph (GC) produced profiles of vapor concentration obtained from samples of the chemical agent deposited as a drop on the surfaces of the matrices. The matrices were exposed to the chemical agent at room temperature, and the degradation reactions were monitored and characterized. A vapor emission test was also performed after a decontamination process. The results showed that on sand, the drop of agent spread laterally while evaporating. On concrete, the drop of the agent was absorbed immediately into the matrix while spreading and evaporating. However, the asphalt surface conserved the agent and slowly released parts of the agent over an extended period of time. The degradation reactions of the agent followed pseudo first order behavior on the matrices. Trace amounts of the residual agent present at the surface were also released as vapor after decontamination, posing a threat to the exposed individual and environment.

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

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.)

Chemical decontamination of the residual heat removal system (RHRS) of Flamanville 1

International Nuclear Information System (INIS)

Steinkuhler, Claude; Coomans, Reginald; Koen, Lenie

2007-01-01

The purpose of the decontamination of the RHRS at Flamanville 1 was the reduction of the general dosimetry and the elimination of hot spots. This was done to allow the maintenance on the RHRS equipment. The main challenge of this project was the execution of a complicated operation on the critical path of a shutdown. The redox attack of the oxides at the surface of the circuit in Flamanville, was performed by an EDF qualified process of the EMMAC family. The functions required by the decontamination system were very diverse and therefore an existing decontamination loop, which was previously developed for the decontamination of small system volumes, was re-developed and adapted for bigger circuits. Due to different reasons, an important delay on the planning happened. Therefore, only one cycle EMMAg was performed, totalling 2 hours of decontamination. Despite this, a DRRF (dose rate reduction factor) of 3,7 average was reached. The re-designed equipment and a shortened process were validated during this project. An acceptable DRRF was reached with no delay on the critical path. The capability of maintenance on the RHRS equipment is recovered with a gain of factor 5 on dosimetry. (authors)

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)

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.

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

Use of a human skin in vitro model to investigate the influence of 'every-day' clothing and skin surface decontamination on the percutaneous penetration of organophosphates.

Science.gov (United States)

Moore, C A; Wilkinson, S C; Blain, P G; Dunn, M; Aust, G A; Williams, F M

2014-08-17

Organophosphates (OPs) are widely used in agriculture. Many studies have investigated the capability of personal protective equipment (PPE) to reduce chemical exposure; however, investigations into the protective effect of 'every-day' clothing are rare. The purpose of this study was to investigate the protective effect of 'every-day' clothing against dermal exposure and to measure early decontamination of skin following exposure to chlorpyrifos and dichlorvos. Using human skin in vitro, absorption of (14)C-labelled chlorpyrifos (500 ng/cm(2)), was shown to be significantly reduced when applied to clothed skin (cotton shirt), regardless of application vehicle (isopropanol (IPA) or propylene glycol (PG)). The majority of applied dose was retained within the clothing after 4 h exposure. Significant reduction in absorption of chlorpyrifos (in PG) was seen through clothed skin when supplemented with skin decontamination at 4 h, compared with clothed skin decontaminated after 24 h, however, this was not observed with IPA. Absorption of dichlorvos (5 μg/cm(2)) was greater through unclothed skin than chlorpyrifos for all vehicles (IPA, isopropyl myristate (IPM) and PG). Significant reduction in absorption was observed when decontaminating clothed skin at 30 min, compared with decontamination at 24 h (post-exposure) for all vehicles. indicate that 'every-day' clothing is effective at reducing exposure to chemicals in contact with skin. Washing the skin surface immediately following removal of exposed clothing can further reduce exposure, depending on the properties of the chemical and vehicle applied. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Effect of Decontamination of Feed Mixtures by Heat Treatment and Gamma Radiation on Growth and Feed Conversion in Fattening Pigs; Effet de la Decontamination de Melanges Alimentaires par Traitement Thermique et Irradiation Gamma sur la Croissance et sur la Conversion des Aliments Chez les Porcs d'Elevage; Vliyanie obezzarazhivaniya kormovykh smesej teplovoj obrabotkoj i gamma-oblucheniem na rost i.konversiyu pishchi u otkarmlivaemykh svinej; Efecto de la Descontaminacion por Tratamiento Termico e Irradiacion Gamma de Piensos Compuestos Sobre el Desarrollo y Engorde de Cerdos Cebones

Energy Technology Data Exchange (ETDEWEB)

Dammers, J.; Kampelmacher, E. H.; Edel, W.; Van Schothorst, M. [Research Institute for Animal Nutrition, Hoorn (Netherlands); National Institute of Public Health, Utrect (Netherlands)

1966-11-15

for the groups fed untreated, heat-treated and irradiated meal, respectively. The feed figures, (kg intake/kg growth) were 3.30, 3.23 and 3.24, respectively, for these groups. From these results the conclusion can be drawn that neither irradiation nor heat decontamination had any adverse effect on the nutritional value of meals in these tests. In all instances the required vitamins were added to the meals subsequent to decontamination treatment. As a further study of the effect of the bacteriological condition of an animal feed mixture on Salmonella, samples of excretion faeces from each animal were examined twice a week for the presence of Salmonella. In the untreated-meal group Salmonellae were isolated in 13 cases. Faeces of pigs fed irradiated or heat-treated meal were free from Salmonellae throughout the whole test period. This demonstrates the efficiency of the decontamination treatments used and, at the same time, the efficacy of such processing methods in the prevention of the occurrence of'healthy Salmonella carriers amongst pigs. (author) [French] Au cours des dernieres annees, on a fait dans le monde entier la demonstration du role determinant, dans la salmonellose de l'homme, des produits alimentaires d'orgine animale contamines par Salmonella. De nouvelles recherches ont montre que les nourritures destinees aux animaux et contaminees par Salmonella sont le premier maillon de la chaine qui peut mener a la contamination des denrees alimentaires. On a constate que l'irradiation (radicidation de Salmonella) constituait un moyen prometteur de decontamination des nourritures destinees a la consommation animale et de leurs ingredients. Les auteurs ont cherche a determiner si les melanges alimentaires ainsi traites ne perdent rien de leur valeur nutritive pour l'elevage du porc. L'experience a consiste a elever trois groupes de huit porcs, l'un recevant des aliments irradies a 1 Mrad de rayons {gamma} de {sup 60}Co, l'autre des aliments decontamines par la

Thixotropic corrosive gels for nuclear decontamination

International Nuclear Information System (INIS)