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 and decommissioning of TAN radioactive liquid-waste-evaporator system (PM-2A). Final report

International Nuclear Information System (INIS)

Smith, D.L.

1983-03-01

This report describes the decontamination and decommissioning of the Test Area North (TAN) liquid waste evaporator (PM-2A). The PM-2A facility included the aboveground evaporator system, two underground holding tanks and feedlines, an electrical distribution subsystem, and one above ground concrete tank. Much surface soil of the PM-2A area was also radioactively contaminated. Stabilization of the liquid and sludge in the holding tanks, a major task, was achieved by pumping most of the liquid into 55-gal drums and mixing it with cement. The drums were buried in the Radioactive Waste Management Complex (RWMC). The remaining liquid and sludge were dried in place by layers of diatomaceous earth. The most contaminated surface soil was removed, and the area backfilled with clean topsoil and graded, reducing the surface radiation field to background. A 6-ft-high chain link fence now surrounds the area. Most of the area was seeded to crested wheatgrass. 46 figures, 9 tables

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.)

Membrane Treatment of Liquid Salt Bearing Radioactive Wastes

International Nuclear Information System (INIS)

Dmitriev, S. A.; Adamovich, D. V.; Demkin, V. I.; Timofeev, E. M.

2003-01-01

The main fields of introduction and application of membrane methods for preliminary treatment and processing salt liquid radioactive waste (SLRW) can be nuclear power stations (NPP) and enterprises on atomic submarines (AS) utilization. Unlike the earlier developed technology for the liquid salt bearing radioactive waste decontamination and concentrating this report presents the new enhanced membrane technology for the liquid salt bearing radioactive waste processing based on the state-of-the-art membrane unit design, namely, the filtering units equipped with the metal-ceramic membranes of ''TruMem'' brand, as well as the electrodialysis and electroosmosis concentrators. Application of the above mentioned units in conjunction with the pulse pole changer will allow the marked increase of the radioactive waste concentrating factor and the significant reduction of the waste volume intended for conversion into monolith and disposal. Besides, the application of the electrodialysis units loaded with an ion exchange material at the end polishing stage of the radioactive waste decontamination process will allow the reagent-free radioactive waste treatment that meets the standards set for the release of the decontaminated liquid radioactive waste effluents into the natural reservoirs of fish-farming value

Active Waste Materials Corrosion and Decontamination Tests

International Nuclear Information System (INIS)

Danielson, M.J.; Elmore, M.R.; Pitman, S.G.

2000-01-01

Stainless steel alloys, 304L and 316L, were corrosion tested in representative radioactive samples of three actual Hanford tank waste solutions (Tanks AW-101, C-104, AN-107). Both the 304L and 316L exhibited good corrosion performance when immersed in boiling waste solutions. The maximum general corrosion rate was 0.015 mm/y (0.60 mils per year). Generally, the 304L had a slightly higher rate than the 316L. No localized attack was observed after 122 days of testing in the liquid phase, liquid/vapor phase, or vapor phase. Radioactive plate-out decontamination tests indicated that a 24-hour exposure to 1 und M HNO 3 could remove about 99% of the radioactive components in the metal film when exposed to the C-104 and AN-107 solutions. The decontamination results are less certain for the AW-101 solution, since the initial contamination readings exceeded the capacity of the meter used for this test

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

New decontamination processes for liquid effluents and solid materials

International Nuclear Information System (INIS)

Faure, S.

2008-01-01

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

Decontamination of Savannah River Plant waste glass canisters

International Nuclear Information System (INIS)

Rankin, W.N.

1982-01-01

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

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

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

International Nuclear Information System (INIS)

Betts, S.E.

1993-01-01

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

Wow Technology’s innovative radioactive liquid waste treatment

Energy Technology Data Exchange (ETDEWEB)

Marin, A.

2015-07-01

WOW presents its revolutionary technology and equipment for liquid radioactive waste treatment: outperforming ultimate water decontamination and purification process, enhanced sludge concentration, no secondary waste nor consumables, fully automated, remote controlled and self-decontaminating device. The WOW’s technology is based upon a never before observed discovery of fluid dynamics science: the possibility of performing a molecular separation between solute and suspended elements and the solvent. The combination of such a molecular separation process with a standard vacuum evaporation improves the abatement performances by thousands of times, with respect to those of the state of the art vacuum evaporators. In addition to this, no secondary waste is produced during the process, as no filters, membranes, resins or additives are used. WOW equipment, automated and remote controlled, self decontaminates after use and can be designed and constructed either tailored to the application needs or with a modular approach for enhanced transportability and application flexibility. After the preliminary verification by CNR, the Italian National Research Center, Wow Technology decontamination device was tested c/o LENA, the Laboratory of Applied Nuclear Energy of the University of Pavia, Italy with a simulated solution 6000 times more contaminated than the nuclear reactor’s cooling water of Fukushima-Daiichi NPP. In addition to that, WOW Technology was also used in a real case at the Radiochemistry laboratory of the Pavia’s University Chemistry department. Both the above mentioned contaminated fluids have been successfully decontaminated without production of additional or secondary waste WOW Technology has already performed on industrial scale c/o the Nuclear Repository of S.S.M. in Saluggia, Italy: 45000 liters of acid radioactive solution have been successfully decontaminated to a Decontamination Factor (DF) of 335000 for Cs-137 by one single evaporation step and

Decontaminating method for radioactive contaminant

International Nuclear Information System (INIS)

Suzuki, Ken-ichi.

1994-01-01

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

Assessment of the proposed decontamination and waste treatment facility at LLNL

International Nuclear Information System (INIS)

Cohen, J.J.

1987-01-01

To provide a centralized decontamination and waste treatment facility (DWTF) at LLNL, the construction of a new installation has been planned. Objectives for this new facility were to replace obsolete, structurally and environmentally sub-marginal liquid and solid waste process facilities and decontamination facility and to bring these facilities into compliance with existing federal, state and local regulations as well as DOE orders. In a previous study, SAIC conducted a preliminary review and evaluation of existing facilities at LLNL and cost effectiveness of the proposed DWTF. This document reports on a detailed review of specific aspects of the proposed DWTF

Decontamination factors of ceramic filter in radioactive waste incineration system

International Nuclear Information System (INIS)

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

1987-01-01

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

Development of Decontamination Methods using Liquid/Supercritical CO2

International Nuclear Information System (INIS)

Park, Kwang Heon; Koh, Moon Sung; Yoon, Chung Hyun; Kim, Hong Doo; Kim, Hak Won

1994-01-01

A major problem of nuclear energy is the production of radioactive wastes. Needs for more environmentally favorable method to decontaminate radioactive contaminants make the use of liquid/supercritical CO2 as a solvent medium. In removing radioactive metallic contaminants under CO2 solvent, two methods - use of chelating ligands and that of water in CO2 emulsion - are possible. In the chelating ligand method, a combination of ligands that can make synergistic effects seems important. We discuss about the properties of microemulsion formed by F-AOT. By adding acid in water core, decontamination of metallic parts, soils were possible

Reactor component chemical decontamination-developments in waste handling and disposal

International Nuclear Information System (INIS)

Papesch, R.; Atwood, K.L.

1989-01-01

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

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)

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

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

Decontamination and decommissioning techniques for research reactors

International Nuclear Information System (INIS)

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

2002-05-01

Evaluation of soil decontamination process and the liquid decontamination waste treatment technology are investigation of organic acid as a decontamination agent, investigation of the liquid waste purification process and identification of recycling the decontamination agents. Participation on IAEA CRP meeting are preparation of IAEA technical report on 'studies on decommissioning of TRIGA reactors and site restoration technologies' and exchange the research result, technology, experience and safety regulation of the research reactor D and D of USA, Great Britain, Canada, Belgium, Italy, India and so forth

Decontamination of liquid radioactive wastes using seeded ultrafiltration

International Nuclear Information System (INIS)

Kavanagh, P.; Goldsmith, A.

1997-01-01

A number of techniques may be used to treat radioactive wastes. This paper presents a discussion of the relative merits of two of these: ion exchange and membrane filtration, and discusses the overall benefit of using seeded filtration to combine the advantages of each, with selected examples of where these techniques have been used. Evaporation is another technique that can be used, however, because of its high capital and operating costs its use is limited and it is not discussed here. Examples of the decontamination of standard solutions by novel materials tested by the Novel Absorber Evaluation Club are presented, and the advantages of the new PAN-based absorbers discussed

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

Impact of decontamination on LWR radioactive waste treatment systems

International Nuclear Information System (INIS)

Hoenes, G.R.; Perrigo, L.D.; Divine, J.R.; Faust, L.G.

1979-01-01

Only at N-Reactor is there a means to accommodate radwaste produced during decontamination. The Dresden system is expected to be ready to accommodate such solutions by the summer of 1979. Solidification of the processed decontamination waste may be a significant problem. There is doubt that the materials in current radwaste treatment systems can handle chemicals from a concentrated process. The total storage volume, for concentrated decontamination, is not sufficient in existing radwaste treatment systems. Greater attention should be placed on designing reactors and radwaste treatment systems for decontamination. A means of handling waste material resulting from leaks in the primary system during the decontamination must be developed. On-site storage of solidified decontamination wastes may be a viable option, but license amendments will be necessary

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.)

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

International Nuclear Information System (INIS)

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

2008-01-01

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

W-12 valve pit decontamination demonstration

International Nuclear Information System (INIS)

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

1995-12-01

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

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.)

Methodology development for radioactive waste treatment of CDTN/BR - liquid low-level radioactive wastes

International Nuclear Information System (INIS)

Morais, Carlos Antonio de

1996-01-01

The radioactive liquid wastes generated in Nuclear Technology Development Centre (CDTN) were initially treated by precipitation/filtration and then the resulting wet solid wastes were incorporated in cement. These wastes were composed of different chemicals and different radioactivities and were generated by different sectors. The objective of the waste treatment method was to obtain minimum wet solid waste volume and decontamination and minimum operational cost. The composition of the solid wastes were taken into consideration for compatible cementation process. Approximately 5,400 litres of liquid radioactive wastes were treated by this process during 1992-1995. The volume reduction was 1/24 th and contained 20% solids. (author)

Low-waste technology of prevention, decontamination and localization of radioactive contamination

International Nuclear Information System (INIS)

Kizhnerov, L. V.; Konstantinov, Ye. A.; Prokopenko, V. A.; Sorokin, N. M.

1997-01-01

The report presents the results of research in developing a low-waste technology of prevention, decontamination and localization of radioactive contamination founded on the of easily removed protective polymeric coating based on water and alcohol latexes and dispersion of polymers with special activating additives. The developed technology provides for the reduction of weakly fixed radioactive contamination of non-painted and painted surfaces to admissible levels (as a rule), it securely prevents and localizes contamination and does not generate secondary liquid radioactive wastes

Studies on radioactive liquid waste treatment by reverse osmosis

International Nuclear Information System (INIS)

Koyama, Akio; Shimoura, Kazukuni; Tsutsui, Tenson

1982-01-01

Reverse osmosis is a simple process and has relatively high decontamination factor comparing to other processes used for the treatment of radioactive liquid waste. Furthermore the quantity of secondary waste of this process is small. In this study, test solution containing nine elements such as cesium, strontium, cobalt etc. in chloride forms are treated by reverse osmosis. Permeate rate decreases as the increase of osmotic pressure of feed solution and is expressed by linear equation. Decontamination factor of cations of univalency is more than ten, and about one tenth of that of bivalency. Decontamination factors of all the elements used in this experiment are approximately estimated using the solution-diffusion model. (author)

Dilute chemical decontamination resins and the mixed waste issue

International Nuclear Information System (INIS)

Denault, R.P.; Hallman, J.T.

1988-01-01

The decontamination of reactor primary systems, sub-systems and components is an important method used to reduce the occupational radiation exposure of nuclear plant personnel. The waste produced by the application of this technology is mainly solid in the form of ion exchange resins. As a result of a recent agreement between the Environmental Protection Agency (EPA) and the Nuclear Regulatory Commission (NRC), all radioactive waste must meet EPA burial criteria. The chemicals used in a decontamination and certain metals dissolved during the process, primarily chromium, could render the waste hazardous as well as radioactive or more commonly called a mixed waste. This paper defines mixed waste as described in the EPA directive 9432.00-2, and examine the criteria by which waste is categorized as hazardous. The decontamination waste resin generated by two processes, the CAN-DEREM and the LOMI process, is described in detail. Waste data obtained from decontaminations performed by LN Technologies Corporation including chemical, metal and radionuclide loadings on resins from both PWR and BWR applications are presented

Development of a technology and a pilot plant for treatment of small volumes of liquid radioactive waste

Energy Technology Data Exchange (ETDEWEB)

Stefanova, I G; Gradev, G D [Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. for Nuclear Research and Nuclear Energy

1997-02-01

The development of technology for treatment of liquid radioactive waste is described. Waste arisings are estimated. Liquid wastes of concern are mainly low active wastes according to the Bulgarian legislation. The activity is determined by the presence of {sup 134}Cs, {sup 137}Cs, {sup 60}Co, {sup 90}Sr, {sup 144}Ce, {sup 65}Zc, {sup 54}Mn, {sup 110m}Ag. Different precipitation processes are compared. The mixed iron hydroxide - calcium phosphate precipitation is determined as suitable for decontamination of the liquid radioactive waste. Effective decontamination is achieved when precipitation is followed by ion exchange. Additional increase of the decontamination is possible when sorbents are added during the precipitation step. The sorption and desorption of radionuclides on zeolites are studied. Cement solidification and thermal treatment of zeolites are studied for immobilization of radioactive material from precipitation and ion exchange. Both methods produce stable waste forms suitable for containment of the radionuclides. (author). 17 refs, 3 figs, 12 tabs.

Biochemical process of low level radioactive liquid simulation waste containing detergent

International Nuclear Information System (INIS)

Kundari, Noor Anis; Putra, Sugili; Mukaromah, Umi

2015-01-01

Research of biochemical process of low level radioactive liquid waste containing detergent has been done. Thse organic liquid wastes are generated in nuclear facilities such as from laundry. The wastes that are cotegorized as hazard and poison materials are also radioactive. It must be treated properly by detoxification of the hazard and decontamination of the radionuclides to ensure that the disposal of the waste meets the requirement of standard quality of water. This research was intended to determine decontamination factor and separation efficiensies, its kinetics law, and to produce a supernatant that ensured the environmental quality standard. The radioactive element in the waste was thorium with activity of 5.10 −5 Ci/m 3 . The radioactive liquid waste which were generated in simulation plant contains detergents that was further processed by aerobic biochemical process using SGB 103 bacteria in a batch reactor equipped with aerators. Two different concentration of samples were processed and analyzed for 212 hours and 183 hours respectively at a room temperature. The product of this process is a liquid phase called as supernatant and solid phase material called sludge. The chemical oxygen demand (COD), biological oxygen demand (BOD), suspended solid (SS), and its alpha activity were analyzed. The results show that the decontamination factor and the separation efficiency of the lower concentration samples are higher compared to the samples with high concentration. Regarding the decontamination factor, the result for 212 hours processing of waste with detergent concentration of 1.496 g/L was 3.496 times, whereas at the detergent concentration of 0.748 g/L was 15.305 times for 183 hours processing. In case of the separation efficiency, the results for both samples were 71.396% and 93.465% respectively. The Bacterial growth kinetics equation follow Monod’s model and the decreasing of COD and BOD were first order with the rate constant of 0.01 hour −1

Biochemical process of low level radioactive liquid simulation waste containing detergent

Energy Technology Data Exchange (ETDEWEB)

Kundari, Noor Anis, E-mail: nooranis@batan.go.id; Putra, Sugili; Mukaromah, Umi [Sekolah Tinggi Teknologi Nuklir – Badan Tenaga Nuklir Nasional Jl. Babarsari P.O. BOX 6101 YKBB Yogyakarta 55281 Telp : (0274) 48085, 489716, Fax : (0274) 489715 (Indonesia)

2015-12-29

Research of biochemical process of low level radioactive liquid waste containing detergent has been done. Thse organic liquid wastes are generated in nuclear facilities such as from laundry. The wastes that are cotegorized as hazard and poison materials are also radioactive. It must be treated properly by detoxification of the hazard and decontamination of the radionuclides to ensure that the disposal of the waste meets the requirement of standard quality of water. This research was intended to determine decontamination factor and separation efficiensies, its kinetics law, and to produce a supernatant that ensured the environmental quality standard. The radioactive element in the waste was thorium with activity of 5.10{sup −5} Ci/m{sup 3}. The radioactive liquid waste which were generated in simulation plant contains detergents that was further processed by aerobic biochemical process using SGB 103 bacteria in a batch reactor equipped with aerators. Two different concentration of samples were processed and analyzed for 212 hours and 183 hours respectively at a room temperature. The product of this process is a liquid phase called as supernatant and solid phase material called sludge. The chemical oxygen demand (COD), biological oxygen demand (BOD), suspended solid (SS), and its alpha activity were analyzed. The results show that the decontamination factor and the separation efficiency of the lower concentration samples are higher compared to the samples with high concentration. Regarding the decontamination factor, the result for 212 hours processing of waste with detergent concentration of 1.496 g/L was 3.496 times, whereas at the detergent concentration of 0.748 g/L was 15.305 times for 183 hours processing. In case of the separation efficiency, the results for both samples were 71.396% and 93.465% respectively. The Bacterial growth kinetics equation follow Monod’s model and the decreasing of COD and BOD were first order with the rate constant of 0

Biochemical process of low level radioactive liquid simulation waste containing detergent

Science.gov (United States)

Kundari, Noor Anis; Putra, Sugili; Mukaromah, Umi

2015-12-01

Research of biochemical process of low level radioactive liquid waste containing detergent has been done. Thse organic liquid wastes are generated in nuclear facilities such as from laundry. The wastes that are cotegorized as hazard and poison materials are also radioactive. It must be treated properly by detoxification of the hazard and decontamination of the radionuclides to ensure that the disposal of the waste meets the requirement of standard quality of water. This research was intended to determine decontamination factor and separation efficiensies, its kinetics law, and to produce a supernatant that ensured the environmental quality standard. The radioactive element in the waste was thorium with activity of 5.10-5 Ci/m3. The radioactive liquid waste which were generated in simulation plant contains detergents that was further processed by aerobic biochemical process using SGB 103 bacteria in a batch reactor equipped with aerators. Two different concentration of samples were processed and analyzed for 212 hours and 183 hours respectively at a room temperature. The product of this process is a liquid phase called as supernatant and solid phase material called sludge. The chemical oxygen demand (COD), biological oxygen demand (BOD), suspended solid (SS), and its alpha activity were analyzed. The results show that the decontamination factor and the separation efficiency of the lower concentration samples are higher compared to the samples with high concentration. Regarding the decontamination factor, the result for 212 hours processing of waste with detergent concentration of 1.496 g/L was 3.496 times, whereas at the detergent concentration of 0.748 g/L was 15.305 times for 183 hours processing. In case of the separation efficiency, the results for both samples were 71.396% and 93.465% respectively. The Bacterial growth kinetics equation follow Monod's model and the decreasing of COD and BOD were first order with the rate constant of 0.01 hour-1.

Design of mobile receiving and treatment equipment for radioactive liquid waste

International Nuclear Information System (INIS)

Kong Jinsong; Guo Weiqun; Lu Jingbin

2012-01-01

The advantage and disadvantage of radioactive liquid waste treatment technology are analyzed in this paper. The experimental disposal equipment for radioactive liquid waste with complicated sources is designed by combining the far infrared calcification technology with evaporation technology. It has advantages of low energy consuming and high decontamination efficiency. The frothy and dirt appear rarely in this equipment. (authors)

Decontamination method for radiation contaminated metal

International Nuclear Information System (INIS)

Enda, Masami; Hosaka, Katsumi; Sakai, Hitoshi.

1997-01-01

An organic acid solution is used as a decontamination liquid, and base materials of radiation contaminated metals are dissolved in the solution. The concentration of the organic acid is measured, and the organic acid is supplied by an amount corresponding to the lowering of the concentration. The decontamination liquid wastes generated during the decontamination step are decomposed, and metals leached in the organic acid solution are separated. With such procedures, contamination intruded into the inside of the mother materials of the metals can be removed, and radioactivity of the contaminated metals such as stainless steels and carbon steels can be eliminated, or the radiation level thereof can be reduced. In addition, the amount of secondary wastes generated along with the decontamination can be suppressed. (T.M.)

Chemical hazards from decontamination solutions in low level waste

International Nuclear Information System (INIS)

Leventhal, L.; Miller, A.; Turney, J.; Naughton, M.; IMPELL Corp., Walnut Creek, CA; Electric Power Research Inst., Palo Alto, CA)

1985-01-01

Recent regulations are focussing more attention on the non-radioactive matrix materials associated with radioactive wastes. Decontamination of operating facilities is becoming a more significant source of low-level waste. This study reviewed the chemical and biological hazards of over 50 decontamination processes. Seventeen of the most prominent hard and soft decontamination processes were examined in detail. The chemical and biological hazards of these seventeen are presented in this paper. These hazards influence the choice of radwaste processing and packaging operations and methods. Federal, state and local regulations further impact on operations and waste disposal. Hazards to personnel, in plant and off-site, resulting from the decontamination cycle are evaluated. 1 fig., 5 tabs

CO2 pellet blasting literature search and decontamination scoping tests report

International Nuclear Information System (INIS)

Archibald, K.E.

1993-12-01

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

Criteria and evaluation of three decontamination techniques

Energy Technology Data Exchange (ETDEWEB)

Tripp, J.L.

1994-01-01

Past decontamination and solvent recovery activities at the Idaho Chemical Processing Plant (ICPP), which is part of the Idaho National Engineering Laboratory (INEL), have resulted in the accumulation of 1.5 million gallons of radioactively contaminated sodium-bearing liquid waste. Future decontamination activities at the ICPP could result in the production of 5 million gallons or more of sodium-bearing waste using the current decontamination techniques of chemical/water flushes and steam jet cleaning. This waste requires a large amount of cold chemical additive to process because the low melting temperatures of sodium and potassium salts cause agglomeration in the bed of the calciner vessel. Criteria have been established for evaluating methods and technologies available for decontaminating equipment and facilities. The criteria were weighted according to their relative importance using a Kepner-Tregoe Problem Solving process. These criteria were used to rank three decontamination techniques new to the ICPP: laser ablation, liquid abrasive blasting and CO{sub 2} pellet blasting, against the standard decontamination techniques of sodium-based chemical cleaning and water/steam jets used.

Criteria and evaluation of three decontamination techniques

International Nuclear Information System (INIS)

Tripp, J.L.

1994-01-01

Past decontamination and solvent recovery activities at the Idaho Chemical Processing Plant (ICPP), which is part of the Idaho National Engineering Laboratory (INEL), have resulted in the accumulation of 1.5 million gallons of radioactively contaminated sodium-bearing liquid waste. Future decontamination activities at the ICPP could result in the production of 5 million gallons or more of sodium-bearing waste using the current decontamination techniques of chemical/water flushes and steam jet cleaning. This waste requires a large amount of cold chemical additive to process because the low melting temperatures of sodium and potassium salts cause agglomeration in the bed of the calciner vessel. Criteria have been established for evaluating methods and technologies available for decontaminating equipment and facilities. The criteria were weighted according to their relative importance using a Kepner-Tregoe Problem Solving process. These criteria were used to rank three decontamination techniques new to the ICPP: laser ablation, liquid abrasive blasting and CO 2 pellet blasting, against the standard decontamination techniques of sodium-based chemical cleaning and water/steam jets used

Use of ferric- and ferrous-salts in liquid waste treatment processes

International Nuclear Information System (INIS)

Efremenkov, V.M.; Toropov, I.G.; Toropova, V.V.; Satsukevich, V.M.; Davidov, J.P.; Jabrodsky, V.N.; Prokshin, N.E.

1995-01-01

Treatment of spent decontamination solutions is the most complicated task in the whole problem of management of liquid radioactive waste, because quite often they have complex compositions, which makes it difficult to find for them effective and non-expensive treatment technology. New methods of treatment of such a waste is proposed based on use of specific sorption ability of ferro- and ferri-species in solution. These species are often present in solution as the by-products, and in combination with other components of decontamination solution they can be used as initial substances for synthesis of valuable sorbents directly in treating solution. Using specific compositions and conditions in solution, it is possible to make liquid waste treatment process more effective and less expensive. Particular examples of this process is presented in this work

Treatment of wastes arising from decontamination process using citric acid as a decontaminate agent

International Nuclear Information System (INIS)

Mierzwa, J.C.; Riella, H.G.; Carvalho, E.U. de

1993-01-01

Wastes arising from equipment decontamination processes from nuclear fuel cycle facilities at Coordenacao de Projetos Especiais - Comissao Nacional de Energia Nuclear, Sao Paulo (COPESP-CNEN/SP) has been studied after using citric acid as a decontaminate agent. Precipitation of uranium and metallic impurities resulted from use of sodium hydroxide or calcium oxide plus a flocculation agent. The removal efficient of uranium was 95% and 99% for sodium hydroxide and calcium oxide respectively. The results shows that this process can be used to test wastes from decontamination processes which use citric acid. (B.C.A.). 03 refs, 08 figs, 04 tabs

Decontamination system study for the Tank Waste Retrieval System

International Nuclear Information System (INIS)

Reutzel, T.; Manhardt, J.

1994-05-01

This report summarizes the findings of the Idaho National Engineering Laboratory's decontamination study in support of the Tank Waste Retrieval System (TWRS) development program. Problems associated with waste stored in existing single shell tanks are discussed as well as the justification for the TWRS program. The TWRS requires a decontamination system. The subsystems of the TWRS are discussed, and a list of assumptions pertinent to the TWRS decontamination system were developed. This information was used to develop the functional and operational requirements of the TWRS decontamination system. The requirements were combined with a comprehensive review of currently available decontamination techniques to produced a set of evaluation criteria. The cleaning technologies and techniques were evaluated, and the CO 2 blasting decontamination technique was chosen as the best technology for the TWRS

Low and medium level liquid waste processing at the new La Hague reprocessing plant

International Nuclear Information System (INIS)

Alexandre, D.

1986-05-01

Reprocessing of spent nuclear fuels produces low and medium activity liquid wastes. These radioactive wastes are decontamined before release in environment. The new effluent processing plant, which is being built at La Hague, is briefly described. Radionuclides are removed from liquid wastes by coprecipitation. The effluent is released after decantation and filtration. Insoluble sludges are conditioned in bitumen [fr

Removal of dissolved and suspended radionuclides from Hanford Waste Vitrification Plant liquid wastes

International Nuclear Information System (INIS)

Sharp, S.D.; Nankani, F.D.; Bray, L.A.; Eakin, D.E.; Larson, D.E.

1990-12-01

It was determined during Preliminary Design of the Hanford Waste Vitrification Plant that certain intermediate process liquid waste streams should be decontaminated in a way that would permit the purge of dissolved chemical species from the process recycle shop. This capability is needed to ensure proper control of product glass chemical composition and to avoid excessive corrosion of process equipment. This paper discusses the process design of a system that will remove both radioactive particulates and certain dissolved fission products from process liquid waste streams. Supporting data obtained from literature sources as well as from laboratory- and pilot-scale tests are presented. 3 refs., 1 fig., 3 tabs

Treatment of fast reactor liquid waste- electrochemical method

International Nuclear Information System (INIS)

Mahato, Swapan Kumar; Sudha, R.; Anthonysamy, S.; Muralidaran, P.

2015-01-01

During the operation of fast reactors, components get wetted by sodium. The sodium wetted primary components such as pumps and intermediate heat exchangers (IHX) in fast reactors are cleaned free of sodium followed by suitable chemical decontamination process before taking them for maintenance or for disposal. This helps in reduction of radiation dose to the operating personnel. Sodium cleaning and decontamination generates large volumes of liquid effluent. The activity in the liquid effluent during sodium cleaning/decontamination is due to 22 Na, 54 Mn, 58 Co, 60 Co, 59 Fe, 137 Cs and 134 Cs. It is required to chemically treat the effluent to reduce the activity levels prior to storage in tanks and transportation to the waste management facility for final disposal. Conventionally the ion exchange method is used for removal of radionuclides which produces large quantities of secondary waste. A method which is suitable both for removal of radionuclides present in low concentration and that avoids generation of large quantities of secondary waste is required. Hence an electrochemical method for metal ion removal is attempted in this work which produces little or no secondary waste. Electrochemical method towards removal of manganese ions was finalized earlier using reticulated vitreous carbon (RVC) from simulated decontamination solution containing a mixture of sulphuric and phosphoric acids. In continuation of the experiments for the removal of cesium ions from simulated cleaning solution which has an alkaline pH, a thin film of nickel hexacyanoferrate (NiHCF) was deposited electrochemically on the surface of RVC. Hexacyanoferrates are known for selectively binding cesium. This NiHCF coated RVC was used for electrodeposition of Cs ions. NiHCF coated and Cs deposited RVC was characterized using SEM/EDX analysis. EDX analysis confirms the presence of Cs on NiHCF coated RVC. (author)

Precipitation-adsorption process for the decontamination of nuclear waste supernates

Science.gov (United States)

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

1982-05-19

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

Liquid waste processing from TRIGA spent fuel storage pits

International Nuclear Information System (INIS)

Buchtela, Karl

1988-01-01

At the Atominstitute of the Austrian Universities and also at other facilities running TRIGA reactors, storage pits for spent fuel elements are installed. During the last revision procedure, the reactor group of the Atominstitute decided to refill the storage pits and to get rid of any contaminated storage pit water. The liquid radioactive waste had been pumped to polyethylene vessels for intermediate storage before decontamination and release. The activity concentration of the storage pit water at the Aominstitute after a storage period of several years was about 40 kBq/l, the total amount of liquid in the storage pits was about 0.25 m 3 . It was attempted to find a simple and inexpensive method to remove especially the radioactive Cesium from the waste solution. Different methods for decontamination like distillation, precipitation and ion exchange are discussed

Liquid waste management at nuclear power plant with WWER

International Nuclear Information System (INIS)

Sabouni, Zahra.

1995-07-01

Management of radioactive wastes have become an area of ever increasing important in nuclear power plants. This is due to the fact that national and international regulations will only allow activity release to the environment based on ALARA principles. Radioactive liquids in the nuclear power plant originate as leakage from equipment, as drains from reactor and auxiliary systems, from decontamination and cleaning operations, from active laundry and from personnel showers. They will collected through the controlled zone of the plant in sumps and automatically pumped to large tanks and then to treatment system. The radioactive wastes are separated and categorized according to their main physical and chemical properties. Methods most frequently applied for low and intermediate level; liquid wastes are: chemical treatment (precipitation), ion exchange, and evaporation, and the decontamination ors are a few hundred, 10 2 -10 4 and 10 3 -10 6 , respectively. As a result of the treatment of radioactive liquids by mentioned methods a concentration of activity takes place in filter media, ion exchange resins, and evaporator concentrates. Before the semi-solid wastes shipped for storage, it has to be solidified in order to handle and transport in easier way. The solidification of wastes can take place by different methods. The general methods are: cementation, and bituminization processes. The selection of each process will depend on many factors which should be considered during the design phase. (author)

Evaluation of destructive methods for managing decontamination wastes

International Nuclear Information System (INIS)

Piciulo, P.L.; Adams, J.W.

1986-01-01

Results are discussed of a laboratory evaluation of destructive methods for processing chemical decontamination wastes. Incineration, acid digestion and wet-air oxidation are capable of degrading decontamination reagents and organic ion-exchange resins. The extent of destruction as a function of operating parameters was waste specific. The reagents used in the testing were: EDTA, oxalic acid, citric acid, picolinic acid and LND-101A

Decommissioning of evaporation technology for processing liquid radioactive waste in UJV Rez, a. s

International Nuclear Information System (INIS)

Tous, M.; Otcovsky, T.; Podlaha, J.

2015-01-01

The UJV Rez, a. s. is the main leader in processing institutional radioactive waste (RAW) in the Czech Republic and the Waste Management Department has been established since the research reactor VVR-S (now LVR-15) was put in operation. Due to the large activities in nuclear research and engineering in the past, a big capacity of waste management technologies was needed. The low pressure compactor for volume reduction of solid RAW, as well as chemical pre-treatment technology of liquid RAW were installed and later the evaporation technology for effective processing the liquid RAW with the cementation and bituminization unit for final conditioning of concentrated liquid RAW were used. During the years of research reactor operation and research activities in UJV Rez, a. s. there were two installed evaporation technologies in row. After the latest evaporator lifetime, changes in liquid RAW production and together with higher decontamination factor requirements, this technology was decided to be decommissioned. The decommissioned evaporation technology was installed and put in operation in 1991. This technology was used for processing liquid aqueous RAW produced from internal research activities and of course for external producers and institutions (e.g. universities, medicine, research institutes, industry). The approved decommissioning plan was prepared and the licence for immediate decommissioning was obtained in 2012. Then the decommissioning project started. The preparing stages as dosimetric survey, expected material balance and of course initial decontamination activities were performed. Evaporation technology dismantling and processing the arising RAW were done by the internal staff of Waste Management Department. The total volume of produced RAW was 49,5 m 3 of RAW. The secondary liquid RAW (from decontamination) of amount 1,4 m 3 , contaminated sludge of amount 0,5 m 3 , solid RAW (construction steel) of amount 39,1 m 3 , solid compressible RAW (protective

Removal of some ions from the radioactive liquid wastes by means of membrane techniques

International Nuclear Information System (INIS)

Roman, Gabriela; Garganciuc, Dana; Batrinescu, Gheorghe; Popescu, Georgeta

2000-01-01

The radioactive wastes imply important problems in the pollution control. Contrary to the case of other liquid wastes, which are specifically treated depending on the nature of pollutants, the liquid radioactive wastes are treated as a function of their activity (high, medium or low) and not depending on the nature of radioisotopes. The paper presents the advantages of the membrane processes as comparing with the classical processes in the removal of some ions from liquid radioactive waste up to values admissible of the current standards. Two types of radioactive liquid solutions were processed namely: one solution from the decontamination of the parts of an installation and other from the decontamination of primary circuit of the nuclear power plant. The first solution was treated with ultrafiltration and reverse osmosis, the retention for radioactive and toxic elements ranging between 14 - 69% for ultrafiltration and 63 - 99% for reverse osmosis. The second solution was processed only with reverse osmosis, a retention between 64 - 98% being obtained. The tests proved that by reverse osmosis membrane process a good removal efficiency of radioactive elements from liquid waste is obtained, corresponding to the requirements imposed by the current regulations. (author)

Decomposition Technology Development of Organic Component in a Decontamination Waste Solution

International Nuclear Information System (INIS)

Jung, Chong Hun; Oh, W. Z.; Won, H. J.; Choi, W. K.; Kim, G. N.; Moon, J. K.

2007-11-01

Through the project of 'Decomposition Technology Development of Organic Component in a Decontamination Waste Solution', the followings were studied. 1. Investigation of decontamination characteristics of chemical decontamination process 2. Analysis of COD, ferrous ion concentration, hydrogen peroxide concentration 3. Decomposition tests of hardly decomposable organic compounds 4. Improvement of organic acid decomposition process by ultrasonic wave and UV light 5. Optimization of decomposition process using a surrogate decontamination waste solution

Treatment of liquid wastes from decontamination of nuclear power plants by heterogeneous photocatalysis

International Nuclear Information System (INIS)

Morgada, Maria Eugenia

2002-01-01

In nuclear power plants high radiation fields are produced, not only in the core but also in the auxiliary systems, due, mainly, to the activation of corrosion products by means of a mechanism known as 'Activity Transport'.With the purpose of reducing at minimum values the intensity of radiation fields and of avoiding the operative problems generated by the deposition of oxides in tanks and pipelines, it is necessary to remove the oxide films, carriers of activity, from the components in auxiliary systems in nuclear power plants and this is usually carried on by chemical cleaning.This process, known as decontamination, is done employing mixtures of oligocarboxilic acids such as NTA, EDTA, oxalic acid, citric acid, etc., at concentration nearly 1% and pH 3-4.The resulting liquid wastes of this process cannot be discharged directly to the environment but must be properly treated.Conventional treatments such as thermolysis, chemical oxidation and others show some problems and, in addition, some of these substances are resistant to degradation.Previous work done in the Unidad de Actividad Quimica del Centro Atomico Constituyentes (UAQ-CAC) indicated that Heterogeneous Photocatalysis, belonging to the Advanced Oxidation Technologies (AOTs), could be a useful procedure for the treatment of liquid decontamination wastes. This method consists on the irradiation of an aqueous suspension of a semiconductor, generally TiO 2 , containing the substrate to be degraded, employing wavelengths shorter than the semiconductor's 'band-gap'.In this way, oxidant and reducing molecules are generated.The advantages compared to other AOTs are its low cost, the ability to work at room temperature and pressure, it uses only oxygen as oxidizing agent and can be operated in 'batch' and continuum.In the present work we employed a recycling system, with a black-light tubular UV lamp (366nm) installed inside as the source of illumination, to study the degradation of oxalic and citric acid by

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.)

Assessment of microwave-based clinical waste decontamination unit.

Science.gov (United States)

Hoffman, P N; Hanley, M J

1994-12-01

A clinical waste decontamination unit that used microwave-generated heat was assessed for operator safety and efficacy. Tests with loads artificially contaminated with aerosol-forming particles showed that no particles were detected outside the machine provided the seals and covers were correctly seated. Thermometric measurement of a self-generated steam decontamination cycle was used to determine the parameters needed to ensure heat disinfection of the waste reception hopper, prior to entry for maintenance or repair. Bacterial and thermometric test pieces were passed through the machine within a full load of clinical waste. These test pieces, designed to represent a worst case situation, were enclosed in aluminium foil to shield them from direct microwave energy. None of the 100 bacterial test pieces yielded growth on culture and all 100 thermal test pieces achieved temperatures in excess of 99 degrees C during their passage through the decontamination unit. It was concluded that this method may be used to render safe the bulk of of ward-generated clinical waste.

Membrane treatment of liquid wastes from radiological decontamination operations.

Science.gov (United States)

Svittsov, A A; Khubetsov, S B; Volchek, K

2011-01-01

The paper focuses on the evaluation of membrane filtration for the treatment of liquid radioactive streams generated in area decontamination operations. In this work, semi-permeable membranes were demonstrated to be effective reducing the volume of wastewater containing cesium and cobalt by two orders of a magnitude. The efficiency of membrane separation was enhanced by employing additives that enlarged the size of target radionuclide species and improved their rejection by the membranes. This was achieved by chelation with synthetic water-soluble polymers and by adsorption on micro particles of adsorbent coupled with micelle formation. The effect of wastewater composition and that of the radionuclide-binding additives on the volume reduction was investigated. Membrane treatment is expected to help simplify further processing and decrease disposal costs.

Radiation protection at the RA Reactor in 1993, Part II, Decontamination and actions, collection of liquid effluents and solid radioactive waste

International Nuclear Information System (INIS)

Mandic, M.; Vukovic, Z.; Lazic, S.; Plecas, I.; Voko, A.

1993-01-01

Certain amount of solid waste results from RA reactor operation, the mean quantity of which depends on the duration of reactor operation and related activities. During repair, when reactor is not operated as well under accidental conditions, the quantity of waste is higher, dependent on the type of repair and comprehensiveness of decontamination of the working surface, contaminated tools and components. The waste is sorted and packed on the spot where they appeared according to the existing regulations and principles of radiation protection with aim to minimize unnecessary exposure of the radiation protection personnel who deals with control, transport, radioactive waste treatment and decontamination. During exceptional operations (decontamination, repair, bigger volume of contaminated material, etc.) professional staff of the Radiation protection department gives recommendations and helps in planning the actions related to repair, sorting and packaging of radioactive waste in special containers, identification of the contaminants, etc. [sr

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

Idaho Nuclear Technology and Engineering Center Newly Generated Liquid Waste Demonstration Project Feasibility Study

International Nuclear Information System (INIS)

Herbst, A.K.

2000-01-01

A research, development, and demonstration project for the grouting of newly generated liquid waste (NGLW) at the Idaho Nuclear Technology and Engineering Center is considered feasible. NGLW is expected from process equipment waste, decontamination waste, analytical laboratory waste, fuel storage basin waste water, and high-level liquid waste evaporator condensate. The potential grouted waste would be classed as mixed low-level waste, stabilized and immobilized to meet RCRA LDR disposal in a grouting process in the CPP-604 facility, and then transported to the state

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)

Pipe Decontamination Involving String-Foam Circulation

International Nuclear Information System (INIS)

Turchet, J.P.; Estienne, G.; Fournel, B.

2002-01-01

Foam applications number for nuclear decontamination purposes has recently increased. The major advantage of foam decontamination is the reduction of secondary liquid wastes volumes. Among foam applications, we focus on foam circulation in contaminated equipment. Dynamic properties of the system ensures an homogeneous and rapid effect of the foam bed-drifted chemical reagents present in the liquid phase. This paper describes a new approach of foam decontamination for pipes. It is based on an alternated air and foam injections. We called it 'string-foam circulation'. A further reduction of liquid wastes is achieved compared to continuous foam. Secondly, total pressure loss along the pipe is controlled by the total foam length in the pipe. It is thus possible to clean longer pipes keeping the pressure under atmospheric pressure value. This ensures the non dispersion of contamination. This study describes experimental results obtained with a neutral foam as well with an acid foam on a 130 m long loop. Finally, the decontamination of a 44 meters pipe is presented. (authors)

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)

Decomposition Technology Development of Organic Component in a Decontamination Waste Solution

Energy Technology Data Exchange (ETDEWEB)

Jung, Chong Hun; Oh, W. Z.; Won, H. J.; Choi, W. K.; Kim, G. N.; Moon, J. K

2007-11-15

Through the project of 'Decomposition Technology Development of Organic Component in a Decontamination Waste Solution', the followings were studied. 1. Investigation of decontamination characteristics of chemical decontamination process 2. Analysis of COD, ferrous ion concentration, hydrogen peroxide concentration 3. Decomposition tests of hardly decomposable organic compounds 4. Improvement of organic acid decomposition process by ultrasonic wave and UV light 5. Optimization of decomposition process using a surrogate decontamination waste solution.

Treatment of low-level liquid radioactive wastes by electrodialysis

International Nuclear Information System (INIS)

DelDebbio, J.A.; Donovan, R.I.

1986-01-01

This paper presents the results of pilot plant studies on the use of electrodialysis (ED) for the removal of radioactive and chemical contaminants from acidic low-level radioactive wastes resulting from nuclear fuel reprocessing operations. Decontamination efficiencies are reported for strontium-90, cesium-137, iodine-129, ruthenium-106 and mercury. Data for contaminant adsorption on ED membranes and liquid waste volumes generated are also presented

Method of heat decomposition for chemical decontaminating resin waste

International Nuclear Information System (INIS)

Kikuchi, Akira.

1988-01-01

Purpose: To make resin wastes into non-deleterious state, discharge them into a resin waste storage tank of existent radioactive waste processing facility and store and dispose them. Constitution: In the processing of chemical decontaminating resin wastes, iron exchange resins adsorbing chemical decontaminating agents comprising a solution of citric acid, oxalic acid, formic acid and EDTA alone or as a mixture of them are heated to dry, thermally decomposed and then separated from the ion exchange resins. That is, the main ingredients of the chemical decontaminating agents are heat-decomposed when heated and dried at about 250 deg C in air and converted into non-toxic gases such as CO, CO 2 , NO, NO 2 or H 2 O. Further, since combustion or carbonization of the basic materials for the resin is not caused at such a level of temperature, the resin wastes removed with organic acid and chelating agents are transferred to an existent resin waste storage tank and stored therein. In this way, facility cost and radiation exposure can remarkably be decreased. (Kamimura, M.)

Chemical decontamination method for radioactive metal waste

International Nuclear Information System (INIS)

Tanaka, Akio; Onuma, Tsutomu; Yamazaki, Sei; Miura, Haruki.

1993-01-01

The present invention provides a chemical decontamination method for radioactive metal wastes, which are generated from radioactive material handling facilities and the surfaces of which are contaminated by radioactive materials. That is, it has a feature of applying acid dissolution simultaneously with mechanical grinding. The radioactive metal wastes are contained in a vessel such as a barrel together with abrasives in a sulfuric acid solution and rotated at several tens rotation per minute. By such procedures for the radioactive metal wastes, (1) cruds and passive membranes are mechanically removed, (2) exposed mother metal materials are uniformly brought into contact with sulfuric acid and further (3) the mother metal materials dissolve the cruds and the passive membranes also chemically by a reducing dissolution (so-called local cell effect). According to the method of the present invention, stainless steel metal wastes having cruds and passive membranes can rapidly and efficiently be decontaminated to a radiation level equal with that of ordinary wastes. (I.S.)

Chemical Decontamination of Metallic Waste from Uranium Conversion Plant Dismantling

International Nuclear Information System (INIS)

Hwang, D. S.; Choi, Y. D.; Hwang, S. T.; Park, J. H.; Byun, J. I.; Jang, N. S.

2005-01-01

Korea Atomic Energy Research Institute (KAERI) started a decommissioning program of the uranium conversion plant. Pre-work was carried as follows; installation of the access control facility, installation of a changing room and shower room, designation of an emergency exit way and indicating signs, installation of a radiation management facility, preparation of a storage area for tools and equipments, inspection and load test of crane, distribution and packaging of existing waste, and pre-decontamination of the equipment surface and the interior. First, decommissioning work was performed in kiln room, which will be used for temporary radioactive waste storage room. Kiln room housed hydro fluorination rotary kiln for production of uranium tetra-fluoride. The kiln is about 0.8 m in diameter and 5.5 m long. The total dismantled waste was 6,690 kg, 73 % of which was metallic waste and 27 % the others such as cable, asbestos, concrete, secondary waste, etc. And effluent treatment room and filtration room were dismantled for installation of decontamination equipment and lagoon sludge treatment equipment. There were tanks and square mixer in these rooms. The total dismantled waste was 17,250 kg, 67% of which was metallic waste and 33% the others. These dismantled metallic wastes consist of stainless and carbon steel. In this paper, the stainless steel plate and pipe were decontaminated by the chemical decontamination with ultrasonic

Decontamination Study for Mixed Waste Storage Tanks RCRA Closure

International Nuclear Information System (INIS)

Leaphart, D.M.; Reed, S.R.; Rankin, W.N.

1995-01-01

The Savannah River Site (SRS) plans to close six underground tanks storing mixed waste under RCRA regulations. In support of this closure effort, a study was performed to determine the optimal method of decontaminating these tanks to meet the closure requirements. Items consaidered in the evaluation of the decontamination methods included effectiveness, compatibility with existing waste residues, possible cleaning solution disposal methods, and cost

Liquid wastes concentrating and solidifying device

International Nuclear Information System (INIS)

Kamiyoshi, Hideki; Ninokata, Yoshihide.

1985-01-01

Purpose: To provide a device for concentrating to solidify radioactive liquid wastes at large solidifying speed and with high decontaminating coefficient, without requirement for automatic control. Constitution: An asphalt solidifying device is disposed below a centrifugal thin film drier, and powder resulted from the drier is directly solidified with asphalt by utilizing the rotation of the drier for the mixing operation in the asphalt vessel. If abnormality should occur in the operation of the drier, resulting liquid wastes can be received and solidified in the asphalt vessel. The liquid wastes are heated to dry in a vessel main body having the heating surface at the circumferential surface. The vessel main body provided with a nozzle for supplying liquid to be treated disposed slantwise at the upper portion of the heating face, scrapers which rotate and slidingly contact the heating face and nozzles which jet out chemicals to the heating face behind the scrapers. Below the vessel main body, are disposed a funnel-like hopper for receiving falling scales, rotary vanes, and the likes by which the scales are introduced into the asphalt solidifying vessel. (Moriyama, K.)

Cleaning of liquid LLW from decontamination processes using semipermeable membranes

International Nuclear Information System (INIS)

Dulama, M.; Deneanu, N.; Pavelescu, M.

2003-01-01

Of the three processes, which have been used extensively for liquid radioactive waste purification, evaporation and ion exchange are costly and flocculation gives a low degree of purification. By comparison to that, reverse osmosis offers intermediate purification at reasonable cost. Present research is examining the potential of using a membrane filtration system for the removal of dissolved radionuclides, but chemical treatment showed as necessary to convert soluble radionuclides, organic traces and metals to insoluble, filterable species. Liquid wastes within a CANDU station are segregated into normal and low-activity waste streams. The normal-activity waste includes wastes from the laboratories, laundries, some service-building drains, upgrade drains, and decontamination center. The drains from the reactor building, the heavy-water area, the spent-fuel pool, and the resin storage area are also directed to this normal activity wastes from showers and building drains in areas of the service building that would not normally be contaminated. The aqueous liquid wastes from the decontamination center and the other collected wastes from the chemical drain system are currently treated by the membrane plant. Generally, the liquid waste streams are effectively volume-reduced by a combination of continuous crossflow microfiltration (MF), spiral wound reverse osmosis (SWRO) and tubular reverse osmosis membrane technologies. Backwash chemical cleaning wastes from the membrane plant are further volume-reduced by evaporation. The concentrate from the membrane plant is ultimately immobilized with bitumen. The ability of the MF/SWRO technology to remove impurities non-selectively makes it suitable for the treatment of radioactive effluents from operating nuclear plants, with proper membrane selection, feed characterization, system configuration and system chemistry control. The choice of polysulfonate material for membrane was based on the high flow rates achievable with this

Safety analysis of the Chernobyl accident origin decontamination waste burials in Belarus

International Nuclear Information System (INIS)

Skurat, V.V.; Shiryaeva, N.M.; Myshkina, N.K.; Gvozdev, A.A.; Serebryanyj, G.Z.; Golikova, N.B.

2002-01-01

Potential dangerous of the decontamination waste burials was estimated by means of the generalized multicompartmental model. Characteristics of 24 the most large and unfavorable decontamination waste burials are shown and an estimate of their safety is given. The burial effect zones were determined (100-300 m). A reliability of the forecasting estimate of potential dangerous radioactive contamination of ground waters near the burials was checked on example of the Dudichi decontamination waste burial

The Comparison on Treatment Method of Liquid Radioactive Waste in Yonggwang No 3 and 4 and No 5 and 6

International Nuclear Information System (INIS)

Yeom, Yu Sun; Kim, Soong Pyung; Lee, Seung Jin

2004-01-01

Most of the low-level liquid radioactive wastes generated from PWR plants are classified into high or low total suspended solid(HTDS or LTDS), and into radiochemical and radioactive laundry waste. Although the evaporation process has a high decontamination ability, it has several problems such as corrosion, foam, and congestion. A new liquid waste disposal process using the ion-exchange demineralizer(IED), instead of the current evaporation process, has been introduced into the Yonggwang NPP No 5 and 6. These two methods have been compared to understand the differences in this study. Aspects compared here were the released radioactivity amount of the liquid radioactive wastes, the dose of off-site residents, the decontamination factor, and the amount of the solid radioactive wastes. The IED system is designed to discharge higher radioactivity about 20% than the evaporating system, and the actual radioactivity released from the evaporating and IED system were 0.473 mCi and 1.098 mCi, respectively. The radioactivity released from the IED was 2.32 times higher than that of the evaporating system. The dose of off-site residents was 2.97 x 10 -6 mSv for the evaporating system, and 6.47 x 10 -6 mSv for IED. The decontamination factor(DF) of the evaporator is, in most cases, far lower than the lower limits of detection(LLD) with the Ge-Li detector. Due to the low concentration of the liquid wastes collected from the liquid waste system, the decontamination factor of IED is very low. Since there is not enough data on the amount of solid radioactive wastes generated by the evaporation system, the comparison on these two systems has been conducted on the basis of the design, and the comparison result was that the evaporating system generated more wastes about 40% than IED.

The Comparison on Treatment Method of Liquid Radioactive Waste in Yonggwang No 3 and 4 and No 5 and 6

Energy Technology Data Exchange (ETDEWEB)

Yeom, Yu Sun; Kim, Soong Pyung [Chosun University, Gwangju (Korea, Republic of); Lee, Seung Jin [RedTek CO., LTD., Daejeon (Korea, Republic of)

2004-09-15

Most of the low-level liquid radioactive wastes generated from PWR plants are classified into high or low total suspended solid(HTDS or LTDS), and into radiochemical and radioactive laundry waste. Although the evaporation process has a high decontamination ability, it has several problems such as corrosion, foam, and congestion. A new liquid waste disposal process using the ion-exchange demineralizer(IED), instead of the current evaporation process, has been introduced into the Yonggwang NPP No 5 and 6. These two methods have been compared to understand the differences in this study. Aspects compared here were the released radioactivity amount of the liquid radioactive wastes, the dose of off-site residents, the decontamination factor, and the amount of the solid radioactive wastes. The IED system is designed to discharge higher radioactivity about 20% than the evaporating system, and the actual radioactivity released from the evaporating and IED system were 0.473 mCi and 1.098 mCi, respectively. The radioactivity released from the IED was 2.32 times higher than that of the evaporating system. The dose of off-site residents was 2.97 x 10{sup -6} mSv for the evaporating system, and 6.47 x 10{sup -6} mSv for IED. The decontamination factor(DF) of the evaporator is, in most cases, far lower than the lower limits of detection(LLD) with the Ge-Li detector. Due to the low concentration of the liquid wastes collected from the liquid waste system, the decontamination factor of IED is very low. Since there is not enough data on the amount of solid radioactive wastes generated by the evaporation system, the comparison on these two systems has been conducted on the basis of the design, and the comparison result was that the evaporating system generated more wastes about 40% than IED.

Research and development on treatment of liquid radioactive wastes in Thailand

Energy Technology Data Exchange (ETDEWEB)

Yamkate, P; Sinakhom, F; Punnachaiya, M; Ya-anan, N; Srisorn, S [Office of Atomic Energy for Peace, Bangkok (Thailand). Waste Management Div.

1997-02-01

The studies have been directed towards treatment technologies for low level waste. The simple physico-chemical method has been studied for applying to various kinds of waste streams such as reactor waste, isotope production waste and liquid waste from the hospitals. The characterization of inorganic ion exchangers including the effect of pH, equilibrium time, temperature and concentration of such exchangers were tested. The results revealed that the local simple brand-washed detergents, which are very cheap, can be successfully used for decontamination instead of a more expensive imported decontaminating agent. It was also revealed that chemical precipitation can be successfully used for the treatment of such wastes. In considering an immobilization process for the treated waste, cementation was selected. The basic properties of the cemented waste forms have been investigated including leachability of the cemented sludge resulted from the chemical precipitation of the decontamination waste. The results revealed that the cemented inorganic ion exchangers and the sludge waste exhibit high compressive strength and low leach rates. The compressive strength of 118-207 kg/cm{sup 2} and 15% and 20% waste loading was found to be optimum for the waste forms. A cumulative fraction leached rate from the cemented sludge was found to be about 30 x 10{sup -3} cm/day at 30 day leaching time. (author). 5 refs, 7 tabs.

Research and development on treatment of liquid radioactive wastes in Thailand

International Nuclear Information System (INIS)

Yamkate, P.; Sinakhom, F.; Punnachaiya, M.; Ya-anan, N.; Srisorn, S.

1997-01-01

The studies have been directed towards treatment technologies for low level waste. The simple physico-chemical method has been studied for applying to various kinds of waste streams such as reactor waste, isotope production waste and liquid waste from the hospitals. The characterization of inorganic ion exchangers including the effect of pH, equilibrium time, temperature and concentration of such exchangers were tested. The results revealed that the local simple brand-washed detergents, which are very cheap, can be successfully used for decontamination instead of a more expensive imported decontaminating agent. It was also revealed that chemical precipitation can be successfully used for the treatment of such wastes. In considering an immobilization process for the treated waste, cementation was selected. The basic properties of the cemented waste forms have been investigated including leachability of the cemented sludge resulted from the chemical precipitation of the decontamination waste. The results revealed that the cemented inorganic ion exchangers and the sludge waste exhibit high compressive strength and low leach rates. The compressive strength of 118-207 kg/cm 2 and 15% and 20% waste loading was found to be optimum for the waste forms. A cumulative fraction leached rate from the cemented sludge was found to be about 30 x 10 -3 cm/day at 30 day leaching time. (author). 5 refs, 7 tabs

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)

Cement waste form qualification report: WVDP [West Valley Demonstration Project] PUREX decontaminated supernatant

International Nuclear Information System (INIS)

McVay, C.W.; Stimmel, J.R.; Marchetti, S.

1988-08-01

This report provides a summary of work performed to develop a cement-based, low-level waste formulation suitable for the solidification of decontaminated high-level waste liquid produced as a by-product of PUREX spent fuel reprocessing. The resultant waste form is suitable for interim storage and is intended for ultimate disposal as low-level Class C waste; it also meets the stability requirements of the NRC Branch Technical Position on Waste Form Qualification, May 1983 and the requirements of 10 CFR 61. A recipe was developed utilizing only Portland Type I cement based on an inorganic salts simulant of the PUREX supernatant. The qualified recipe was tested full scale in the production facility and was observed to produce a product with entrained air, low density, and lower-than-expected compressive strength. Further laboratory scale testing with actual decontaminated supernatant revealed that set retarders were present in the supernatant, precluding setting of the product and allowing the production of ''bleed water.'' Calcium nitrate and sodium silicate were added to overcome the set retarding effect and produced a final product with improved performance when compared to the original formulation. This report describes the qualification process and qualification test results for the final product formulation. 7 refs., 38 figs., 21 tabs

Final report on the decontamination of the Curium Source Fabrication Facility

International Nuclear Information System (INIS)

Schaich, R.W.

1983-12-01

The Curium Source Fabrication Facility (CSFF) at Oak Ridge National Laboratory (ORNL) was decontaminated to acceptable contamination levels for maintenance activities, using standard decontamination techniques. Solid and liquid waste volumes were controlled to minimize discharges to the ORNL waste systems. This program required two years of decontamination effort at a total cost of approximately $700K. 5 references, 7 figures, 2 tables

Decontamination of some liquid wastes of medium activity with a new solvent type

International Nuclear Information System (INIS)

Gasparini, G.

1986-01-01

The decontamination of a reference MAWsub(s) (an alkaline solution coming from the solvent washing and an acidic solution consisting of the mixture of aqueous raffinates deriving from uranium and plutonium purification cycles) by hydroxamic acid is reported. The results of the ''in batch'' decontamination tests, using extraction chromatography techniques, are given. The extraction chromatography techniques do not give the expected performances for the tests in column. Discontinuous liquid extraction tests using traced solutions show that Pu, Am, Zr, Nb are extracted but not U and Ru. The strip of Pu, Am and Zr with an oxalic acid solution is quantitative. Continuous tests using mixer settler batteries, and a simulated alkaline solution and complete extraction-reextraction runs using a simulated solution are conducted. The results of a discontinuous conclusive experiments using a true alkaline solution coming from a reprocessing plant are given

Decontamination of alpha contaminated metallic waste by cerium IV redox process

International Nuclear Information System (INIS)

Shah, J.G.; Dhami, P.S.; Gandhi, P.M.; Wattal, P.K.

2012-01-01

Decontamination of alpha contaminated metallic waste is an important aspect in the management of waste generated during dismantling and decommissioning of nuclear facilities. Present work on cerium redox process targets decontamination of alpha contaminated metallic waste till it qualifies for the non alpha waste category for disposal in near surface disposal facility. Recovery of the alpha radio nuclides and cerium from aqueous secondary waste streams was also studied deploying solvent extraction process and established. The alpha-lean secondary waste stream has been immobilised in cement based matrix for final disposal. (author)

Radiation protection at the RA Reactor in 1995, Part -2, Annex 2, Decontamination and actions, collection of liquid effluents and solid radioactive waste

International Nuclear Information System (INIS)

Mandic, M.; Vukovic, Z.; Lazic, S.; Plecas, I.; Voko, A.

1995-01-01

Certain amount of solid waste results from RA reactor operation, the mean quantity of which depends on the duration of reactor operation and related activities. During repair, when reactor is not operated as well under accidental conditions, the quantity of waste is higher, dependent on the type of repair and comprehensiveness of decontamination of the working surface, contaminated tools and components. The waste is sorted and packed on the spot where they appeared according to the existing regulations and principles of radiation protection with aim to minimize unnecessary exposure of the radiation protection personnel who deals with control, transport, radioactive waste treatment and decontamination. During exceptional operations (decontamination, repair, bigger volume of contaminated material, etc.) professional staff of the Radiation protection department gives recommendations and helps in planning the actions related to repair, sorting and packaging of radioactive waste in special containers, identification of the contaminants, etc. [sr

Radiation protection at the RA Reactor in 1998, Part 2, Annex 2, Decontamination and actions, collection of liquid effluents and solid radioactive waste

International Nuclear Information System (INIS)

Mandic, M.; Vukovic, Z.; Bacic, S.; Plecas, I.

1998-01-01

Certain amount of solid waste results from RA reactor operation, the mean quantity of which depends on the duration of reactor operation and related activities. During repair, when reactor is not operated as well under accidental conditions, the quantity of waste is higher, dependent on the type of repair and comprehensiveness of decontamination of the working surface, contaminated tools and components. The waste is sorted and packed on the spot where they appeared according to the existing regulations and principles of radiation protection with aim to minimize unnecessary exposure of the radiation protection personnel who deals with control, transport, radioactive waste treatment and decontamination. During exceptional operations (decontamination, repair, bigger volume of contaminated material, etc.) professional staff of the Radiation protection department gives recommendations and helps in planning the actions related to repair, sorting and packaging of radioactive waste in special containers, identification of the contaminants, etc. [sr

Chemical treatment of liquid radioactive waste at the Boris Kidric Institute

International Nuclear Information System (INIS)

Lazic, S.; Vukovic, Z.; Voko, A.

1989-01-01

The results of lab-scale experiments on the chemical treatment of radioactive liquid waste collected at the Boris Kidric Institute are presented. The radioactive waste was treated by cobalt hexacyanoferrate precipitation followed by flocculation with polyelectrolyte flocculating agents. The main parameters investigated were standing time, pH and ratio of reagents. The flocculating agents were tested by filtration test and floccule stability test. Satisfactory decontamination factors by precipitation at pH 10 and good separation of solid and liquid phase by applying Praestol polyelectrolytes were obtained (author)

Development of waste minimization and decontamination technologies at the Idaho Chemical Processing Plant

International Nuclear Information System (INIS)

Ferguson, R.L.; Archibald, K.E.; Demmer, R.L.

1995-01-01

Emphasis on the minimization of decontamination secondary waste has increased because of restrictions on the use of hazardous chemicals and Idaho Chemical Processing Plant (ICPP) waste handling issues. The Lockheed Idaho Technologies Co. (LITCO) Decontamination Development Subunit has worked to evaluate and introduce new performed testing, evaluations, development and on-site demonstrations for a number of novel decontamination techniques that have not yet previously been used at the ICPP. This report will include information on decontamination techniques that have recently been evaluated by the Decontamination Development Subunit

Technical report on treatment of radioactive slurry liquid waste

International Nuclear Information System (INIS)

Jeong, Gyeong Hwan; Jo, Eun Sung; Park, Seung Kook; Jung, Ki Jung

1999-06-01

By literature survey, this report deals with the technology on typical pre-treatment and filtration of radioactive slurry liquid waste, produced during the operation of TRIGA Mark-II, III research reactor, and produced during the decommission/decontamination of TRIGA Mark-II, III research reactor. It is reviewed pre-treatment procedure, both physical and chemical that optimise the dewatering characteristics, and also surveyed types of dewatering devices based on centrifuges, vacuum and pressure filters with particular reference to various combined field approaches using two or more complementary driving forces to achieve better performance. Dewatering operations and devises on filtration of radioactive slurry liquid waste are also analysed. (author)

Process of liquid radioactive waste treatment in nuclear power plant and development trend

International Nuclear Information System (INIS)

Liu Jiean; Wang Xin; Liu Dan; Zhu Laiye; Chen Bin

2014-01-01

The popular liquid radioactive waste treatment methods in nuclear power plants (NPP) are Chemical precipitation, evaporation, ion exchange, membrane treatment, chemical coagulation and activated carbon absorption and so on. 'Filter + activated carbon absorption (Chemical coagulation) + ion exchange' has a good prospect for development, as its simple process, high decontamination factor, low energy consumption and smaller secondary wastes. Also the process is used in Sanmen and Haiyang Projects. The severe incident in NPP set an even higher demand on liquid radioactive waste treatment. The new type treatment materials, optimization of the existed treatment, combination of treatment and the mobile treatment facility is the development trend in liquid radioactive waste treatment in NPP. (authors)

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.)

Operating safety requirements for the intermediate level liquid waste system

International Nuclear Information System (INIS)

1980-07-01

The operation of the Intermediate Level Liquid Waste (ILW) System, which is described in the Final Safety Analysis, consists of two types of operations, namely: (1) the operation of a tank farm which involves the storage and transportation through pipelines of various radioactive liquids; and (2) concentration of the radioactive liquids by evaporation including rejection of the decontaminated condensate to the Waste Treatment Plant and retention of the concentrate. The following safety requirements in regard to these operations are presented: safety limits and limiting control settings; limiting conditions for operation; and surveillance requirements. Staffing requirements, reporting requirements, and steps to be taken in the event of an abnormal occurrence are also described

Risk comparison of different treatment and disposal strategies of high level liquid radioactive waste

International Nuclear Information System (INIS)

Fang Dong

1997-01-01

The risk of different treatment and disposal strategies of high level liquid radioactive waste from spent fuel reprocessing is estimated and compared. The conclusions obtained are that risk difference from these strategies is very small and high level liquid waste can be reduced to middle and low level waste, if the decontamination factor for 99 Tc is large enough, which is the largest risk contributor in the high level radioactive waste from spent fuel reprocessing. It is also shown that the risk of high level radioactive waste could be reduced by the technical strategy of combining partitioning and transmutation

Pilot scale study of a chemical treatment process for decontamination of aqueous radioactive waste of pakistan research reactor-1

International Nuclear Information System (INIS)

Jan, F.; Hussain, M.; Ahmad, S.S.; Aslam, M.; Haq, E.U.

2007-12-01

Chemical treatment process for the low level liquid radioactive waste generated at PINSTECH was previously optimized on lab-scale making use of coprecipitation of hydrous oxides of iron in basic medium. Ferrous sulfate was used as coagulant. Batch wise application of this procedure on pilot scale has been tested on a 1200 L batch volume of typical PINSTECH liquid waste. Different parameters and unit operations have been evaluated. The required data for the construction of a small size treatment plant envisioned can be used for demonstration/teaching purpose as well as for the decontamination of the waste effluents of the Institute. The lab-scale process parameters were verified valid on pilot scale. It was observed that reagent doses can further be economized with out any deterioration of the Decontamination Factors (DF) achieved or of any other aspect of the process. This simple, cost- effective, DF-efficient and time-smart batch wise process could be coupled with an assortment of other treatment operations thus affording universal application. Observations recorded during this study are presented. (author)

Improved liquid waste processing system of PWR plant

International Nuclear Information System (INIS)

Suehiro, Kazuyasu

1977-01-01

Mitsubishi Heavy Industries, Ltd. has engaged in the improvement and enhancement of waste-processing facilities for PWR power stations, and recently established the improved processing system. With this system, it becomes possible to contain radioactive waste gas semi-permanently within plants and to recycle waste liquid after the treatment, thus to make the release of radioactive wastes practically zero. The improved system has the following features, namely the recycling system is adopted, drain is separated and each separated drain is treated by specialized process, the reboiler type evaporator and the reverse osmosis equipment are used, and the leakless construction is adopted for the equipments. The radioactive liquid wastes in PWR power stations are classified into coolant drain, drain from general equipments, chemical drain and cleaning water. The outline of the improved processing system and the newly developed equipments such as the reboiler type evaporator and the reverse osmosis equipment are explained. With the evaporator, the concentration rate of waste liquid can be raised to about three times, and foaming waste can be treated efficiently. The decontamination performance is excellent. The reverse osmosis treatment is stable and reliable method, and is useful for the treatment of cleaning water. It is also effective for concentrating treatment. The unmanned automatic operation is possible. (Kako, I.)

Decontamination impacts on solidification and waste disposal

International Nuclear Information System (INIS)

Kempf, C.R.; Soo, P.

1988-01-01

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

Chemical Gel for Surface Decontamination

International Nuclear Information System (INIS)

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

2010-01-01

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

Processing of waste solutions from electrochemical decontamination

International Nuclear Information System (INIS)

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

1979-09-01

The use of electropolishing as a decontamination technique will be effective only if we can minimize the amount of secondary waste requiring disposal and economically recycle part of the decontamination electrolyte. Consequently, a solution purification method is needed to remove the dissolved contamination and metal in the electrolyte. This report describes the selection of a purification method for a phosphoric acid electrolyte from the following possible acid reclamation processes: ion exchange, solvent extraction, precipitation, distillation, electrolysis, and membrane separation

Treatment alternatives of liquid radioactive waste containing uranium in phosphoric acid

International Nuclear Information System (INIS)

Bustamante Escobedo, Mauricio

2003-01-01

The UGDR, receives annually 100 [l] of liquid radioactive waste containing, highly acid (pH=0) uranium in phosphoric acid from the Laboratory of Chemical Analysis. This waste must be chemically and radiologically decontaminated before it can be discharged in accordance with local environmental standards. Chemical precipitation and evaporation test were carried out to define the operating conditions for the radiological decontamination of this radioactive waste and to obtain a solid waste that can be conditioned in a cement matrix. The evaporation process generates excellent rates of volume reduction, over 80%, but generates a pulp that is hard handle when submitted to a drying process. Chemical precipitation generates good results for decontaminating these solutions and reducing volume (above 50%) to obtain a uranium free effluent. The treatment with calcium carbonate generated an effluent with a low concentration of polluting agents. A preliminary test was carried out condition these solids in a cement matrix, using ratios of 0.45 waste/cement and 2 of water/cement. The mix prepared with waste from the sodium hydroxide treatment had low mechanical resistance resulting from the saline incrustations. The waste from the calcium carbonate treatment was very porous due to the water evaporation from the highly exothermic reaction between the waste and the cement. The mix of the calcium carbonate generated waste and the cement matrix needs to be optimized, since it generates favorable conditions for adhering with the cement matrix (au)

Decontamination flowsheet development for a waste oil containing mixed radioactive contaminants

International Nuclear Information System (INIS)

Vijayan, S.; Buckley, L.P.

1993-01-01

The majority of waste oils contaminated with both radioactive and hazardous components are generated in nuclear power plant, research lab. and uranium-refinery operations. The waste oils are complex, requiring a detailed examination of the waste management strategies and technology options. It may appear that incineration offers a total solution, but this may not be true in all cases. An alternative approach is to decontaminate the waste oils to very low contaminant levels, so that the treated oils can be reused, burned as fuel in boilers, or disposed of by commercial incineration. This paper presents selected experimental data and evaluation results gathered during the development of a decontamination flowsheet for a specific waste oil stores at Chalk River Labs. (CRL). The waste oil contains varying amounts of lube oils, grease, paint, water, particulates, sludge, light chloro- and fluoro-solvents, polychlorinated biphenyls (PCB), complexing chemicals, uranium, chromium, iron, arsenic and manganese. To achieve safe management of this radioactive and hazardous waste, several treatment and disposal methods were screened. Key experiments were performed at the laboratory-scale to confirm and select the most appropriate waste-management scheme based on technical, environmental and economic criteria. The waste-oil-decontamination flowsheet uses a combination of unit operations, including prefiltration, acid scrubbing, and aqueous-leachage treatment by precipitation, microfiltration, filter pressing and carbon adsorption. The decontaminated oil containing open-quotes de minimisclose quotes levels of contaminants will undergo chemical destruction of PCBs and final disposal by incineration. The recovered uranium will be recycled to a uranium milling process

The dissolution of metal decontamination sludges stored in tanks and their management

Energy Technology Data Exchange (ETDEWEB)

Prokopowicz, R.A.; Phillips, B. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

2011-07-01

The decontamination of stainless steel components is accomplished by the use of alkaline permanganate solutions, followed by an application of solutions of complexing agents such as citric acid or oxalic acid. Spent decontamination solutions comprising residues from both steps were combined in several waste storage tanks, where they have been in storage for several years. In those tanks, a reaction between residual permanganate and unreacted complexing agents produced sludges, consisting mainly of manganese dioxide, that reside in the tanks along with supernatant liquid. In a campaign that was conducted a few years ago, the accumulated waste solution was partially treated and disposed. This treatment consisted of decanting only the supernatant liquid and transporting it to a liquid waste treatment facility that employed a Thin Film Evaporator (TFE) to concentrate the liquid and ultimately produce a bitumen-encapsulated solidified waste form for storage. A study of treatment options for the remaining sludge is reported here. The requirement was to determine a simple means of treating the sludge using existing routine processes and equipment. This will be a significant step toward the decommissioning of the decontamination waste storage tanks. The available equipment at the liquid waste treatment facility was not designed to process sludge or slurries containing a large volume fraction of solids. Laboratory testing was carried out to find a means of dissolving the decontamination waste sludges, preferably in situ, and filtering undissolved solids to meet the feed requirements of the TFE in the liquid waste treatment facility. A concentrated citric acid solution was applied to sludge samples, without the use of externally applied mixing of the reagent and sludge. In all of the samples of actual decontamination waste sludge that were tested, a quantity of undissolved material remained after treatment with citric acid. The quantities were relatively small in volume, and

The dissolution of metal decontamination sludges stored in tanks and their management

International Nuclear Information System (INIS)

Prokopowicz, R.A.; Phillips, B.

2011-01-01

The decontamination of stainless steel components is accomplished by the use of alkaline permanganate solutions, followed by an application of solutions of complexing agents such as citric acid or oxalic acid. Spent decontamination solutions comprising residues from both steps were combined in several waste storage tanks, where they have been in storage for several years. In those tanks, a reaction between residual permanganate and unreacted complexing agents produced sludges, consisting mainly of manganese dioxide, that reside in the tanks along with supernatant liquid. In a campaign that was conducted a few years ago, the accumulated waste solution was partially treated and disposed. This treatment consisted of decanting only the supernatant liquid and transporting it to a liquid waste treatment facility that employed a Thin Film Evaporator (TFE) to concentrate the liquid and ultimately produce a bitumen-encapsulated solidified waste form for storage. A study of treatment options for the remaining sludge is reported here. The requirement was to determine a simple means of treating the sludge using existing routine processes and equipment. This will be a significant step toward the decommissioning of the decontamination waste storage tanks. The available equipment at the liquid waste treatment facility was not designed to process sludge or slurries containing a large volume fraction of solids. Laboratory testing was carried out to find a means of dissolving the decontamination waste sludges, preferably in situ, and filtering undissolved solids to meet the feed requirements of the TFE in the liquid waste treatment facility. A concentrated citric acid solution was applied to sludge samples, without the use of externally applied mixing of the reagent and sludge. In all of the samples of actual decontamination waste sludge that were tested, a quantity of undissolved material remained after treatment with citric acid. The quantities were relatively small in volume, and

DECONTAMINATION/DESTRUCTION TECHNOLOGY DEMONSTRATION FOR ORGANICS IN TRANSURANIC WASTE

Energy Technology Data Exchange (ETDEWEB)

Chris Jones; Javier Del Campo; Patrick Nevins; Stuart Legg

2002-08-01

The United States Department of Energy's Savannah River Site has approximately 5000 55-gallon drums of {sup 238}Pu contaminated waste in interim storage. These may not be shipped to WIPP in TRUPACT-II containers due to the high rate of hydrogen production resulting from the radiolysis of the organic content of the drums. In order to circumvent this problem, the {sup 238}Pu needs to be separated from the organics--either by mineralization of the latter or by decontamination by a chemical separation. We have conducted ''cold'' optimization trials and surrogate tests in which a combination of a mediated electrochemical oxidation process (SILVER II{trademark}) and ultrasonic mixing have been used to decontaminate the surrogate waste materials. The surrogate wastes were impregnated with copper oxalate for plutonium dioxide. Our process combines both mineralization of reactive components (such cellulose, rubber, and oil) and surface decontamination of less reactive materials such as polyethylene, polystyrene and polyvinylchloride. By using this combination of SILVER II and ultrasonic mixing, we have achieved 100% current efficiency for the destruction of the reactive components. We have demonstrated that: The degree of decontamination achieved would be adequate to meet both WIPP waste acceptance criteria and TRUPACT II packaging and shipping requirements; The system can maintain near absolute containment of the surrogate radionuclides; Only minimal pre-treatment (coarse shredding) and minimal waste sorting are required; The system requires minimal off gas control processes and monitoring instrumentation; The laboratory trials have developed information that can be used for scale-up purposes; The process does not produce dioxins and furans; Disposal routes for secondary process arisings have already been demonstrated in other programs. Based on the results from Phase 1, the recommendation is to proceed to Phase 2 and use the equipment at Savannah

Devoluming method of acidic radioactive liquid waste and processing system therefor

International Nuclear Information System (INIS)

Shirai, Takamori; Honda, Tadahiro

1998-01-01

Radioactive liquid wastes such as liquid wastes discharged from chemical decontamination (containing free acids, metal salts dissolved in acids, not-dissolved iron rust and radioactive metals) are introduced to an acid recovering device using a diffusion permeation membrane and separated to a deacidified liquid and separated acid liquid. The separated acid liquid mainly comprising free acids is recovered to a tank for recovered acids, and used repeatedly for removing crud. The deacidified liquid mainly comprising salts is concentrated in a reverse osmosis membrane (RO) concentration device. RO concentrated liquid containing radioactive metals is dried, and salts are decomposed in a drying/salt-decomposing device and separated into metal oxides and a mixed gas of an acidic gas and steams. The gas is cooled in an acid absorbing device and recovered as free acids. The metal oxides containing radioactive metals are solidified. (I.N.)

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

Analysis of the application of decontamination technologies to radioactive metal waste minimization using expert systems

Energy Technology Data Exchange (ETDEWEB)

Bayrakal, Suna [Iowa State Univ., Ames, IA (United States)

1993-09-30

Radioactive metal waste makes up a significant portion of the waste currently being sent for disposal. Recovery of this metal as a valuable resource is possible through the use of decontamination technologies. Through the development and use of expert systems a comparison can be made of laser decontamination, a technology currently under development at Ames Laboratory, with currently available decontamination technologies for applicability to the types of metal waste being generated and the effectiveness of these versus simply disposing of the waste. These technologies can be technically and economically evaluated by the use of expert systems techniques to provide a waste management decision making tool that generates, given an identified metal waste, waste management recommendations. The user enters waste characteristic information as input and the system then recommends decontamination technologies, determines residual contamination levels and possible waste management strategies, carries out a cost analysis and then ranks, according to cost, the possibilities for management of the waste. The expert system was developed using information from literature and personnel experienced in the use of decontamination technologies and requires validation by human experts and assignment of confidence factors to the knowledge represented within.

Analysis of the application of decontamination technologies to radioactive metal waste minimization using expert systems

International Nuclear Information System (INIS)

Bayrakal, S.

1993-01-01

Radioactive metal waste makes up a significant portion of the waste currently being sent for disposal. Recovery of this metal as a valuable resource is possible through the use of decontamination technologies. Through the development and use of expert systems a comparison can be made of laser decontamination, a technology currently under development at Ames Laboratory, with currently available decontamination technologies for applicability to the types of metal waste being generated and the effectiveness of these versus simply disposing of the waste. These technologies can be technically and economically evaluated by the use of expert systems techniques to provide a waste management decision making tool that generates, given an identified metal waste, waste management recommendations. The user enters waste characteristic information as input and the system then recommends decontamination technologies, determines residual contamination levels and possible waste management strategies, carries out a cost analysis and then ranks, according to cost, the possibilities for management of the waste. The expert system was developed using information from literature and personnel experienced in the use of decontamination technologies and requires validation by human experts and assignment of confidence factors to the knowledge represented within

Development of chemical decontamination for low level radioactive wastes

International Nuclear Information System (INIS)

Ichikawa, Seigo; Omata, Kazuo; Obinata, Hiroshi; Nakajima, Yoshihiko; Kanamori, Osamu.

1995-01-01

During routine intermittent inspection and maintenance at nuclear power plants, a considerable quantity of low level radioactive waste is generated requiring release from the nuclear site or treating additionally. To decontaminate this waste for safe release from the nuclear power plant, the first step could be washing the waste in Methylene chloride, CH 2 Cl 2 , to remove most of the paint coating. However, CH 2 Cl 2 washing does not completely remove the paint coating from the waste, which in the next step is shot blasted with plastic bead media to loose and remove the remaining paint coating. Following in succession, in the third step, the waste is washed in a chelate solution, after which most waste is decontaminated and suitable to be released for recycling. The residual chelate solution may be decomposed into nontoxic carbon dioxide and water by an electrolysis process and then safely discharged into the environment. (author)

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

Research and Development of Solar Evaporation on Low Level Radioactive Liquid Waste

Directory of Open Access Journals (Sweden)

ZHANG Hua

2016-02-01

Full Text Available Solar evaporation, which can save energy and obtain the higher decontamination factor, the larger treatment capability with the simpler designed and easy operation, was one of the general methods to treat low level radioactive liquid waste. However, the use of solar evaporation was limited because the facilities had to occupy the larger area and require sunshine for the longer duration, etc. Several cases form USA, Australian, India and South Korea were presented on R&D of solar evaporation to treat low level radioactive liquid waste.

HAZARDOUS WASTE DECONTAMINATION WITH PLASMA REACTORS

Science.gov (United States)

The use of electrical energy in the form of plasma has been considered as a potentially efficient means of decontaminating hazardous waste, although to date only a few attempts have been made to do so. There are a number of relative advantages and some potential disadvantages to...

Technical soaps - a possibility of decontaminating thorium-contaminated waste waters

International Nuclear Information System (INIS)

Drathen, H.; Erichsen, L. v.

1977-01-01

Thorium-contaminated waste waters showing a concentration of thorium higher than 10sup(-5) mol/l can be quantitatively decontaminated by adding soaps. Concentrations of impurity ions of both tap and sea waters have been taken into consideration. As there is no difference between soaps and soap mixtures concerning the quantity of precipitation rates, technical soaps are from the economic point of view best suited for decontaminating thorium-contaminated waste waters. Having a soap concentration of 200% of the stoichiometric amount of thorium and a concentration of impurity ions of 10sup(-2) mol/l, it is assumed that decontamination factors of more than 20 can be reached in one step. (orig.) [de

Removal of actinide elements from liquid scintillation cocktail wastes using liquid-liquid extraction and demulsification techniques

International Nuclear Information System (INIS)

Foltz, K.; Landsberger, S.; Srinivasan, B.; Vandegrift, G.F.

1994-01-01

For many years liquid scintillation cocktail (LSC) wastes have been generated and stored at Argonne National Laboratory (ANL). These wastes are stored in thousands of 10--20 m scintillation vials, many of which contain elements with Z > 88. Because storage space is limited, disposal of this waste is pressing. These wastes could be commercially incinerated if the radionuclides with Z>88 are reduced to sufficiently low levels. However, there is currently no deminimus level for these radionuclides, and separation techniques are still being tested. The University of Illinois is conducting experiments to separate radionuclides with Z > 88 from simulated LSC wastes by using liquid-liquid extraction (LLX) and demulsification techniques. The actinide elements are removed from the LSC by extraction into an aqueous phase after the cocktail has been demulsified. The aqueous and organic phases are separated and the organic phase, now free from radionuclides with Z > 88, can be sent to a commercial incineration facility. The aqueous phase may be treated and disposed of using existing techniques. The LLX separation techniques used solutions of sodium oxalate, aluminum nitrate, and tetrasodium EDTA at varying concentrations. These extractants were mixed with the simulated waste in a 1:1 volume ratio. Using 1.0M Na 4 EDTA salt solutions, decontamination ratios as high as 230 were achieved

Localization of decontamination waste in the territory of Ukraine.; Lokalizatsiya otkhodov dezaktivatsionnykh rabot na territorii Ukrainy.

Energy Technology Data Exchange (ETDEWEB)

Borodin, L P; Zhivotenko, A N [Naukovo-Tekhnyichnij Tsentr z dezaktivatsyiyi ta kompleksnogo povodzhennya z radyioaktivnimi vyidkhodami, Zhovtyi Vodi (Ukraine)

1994-12-31

Various environmental conditions in decontamination waste storage areas in the Zhitomir, Kiev, Chernigov, Rovno, Cherkassy, Sumy Regions of Ukraine are analyzed. Typical designs and basic parameters of decontamination waste storage areas implemented in 17 contractor designs are described. Theoretical grounds of safe storage of decontamination waste in the areas are discussed.

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

International Nuclear Information System (INIS)

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

1972-01-01

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

Innovative processes for the treatment of radioactive liquid wastes

International Nuclear Information System (INIS)

Pacary, V.; Barre, Y.; Plasari, E.

2008-01-01

Full text of publication follows: Because of the high salinity (0.5 to 2 M) of liquid wastes and the variability of their composition, the method which is the most appropriate and commonly used to remove the contaminants consists in the in situ formation of adsorbent particles in the waste stream. This technique is often called coprecipitation. To increase the efficiency of this treatment, a study is performed to point out the impact of the choice of the process and the influence of operating parameters (mean residence time, stirring speed, etc.) on the formation of crystals and ultimately on their ability to capture radionuclide. Barium sulphate was chosen as a reference because it is a well known precipitate and a material used in the decontamination facilities to remove radiostrontium. Two issues are encountered with the classic treatments which are consequences of the variability of effluents composition. On the one hand when high activity effluents have to be treated, the efficiency of the classic processes can not be sufficient and the liquid must be once again decontaminated. Thus the volume of disposal waste produced by the treatment is doubled. On the other hand when low activity effluents have to be treated, the classic processes produce a low activity waste. Consequently the volume of storage occupied by this waste is disproportionate with regard to its low activity. To return the more flexible process, various configurations were tested. They can be classified in two categories: improvements of the classic treatments and new types of reactors. Because of the good results which are obtained, these processes are patent pending. To support the experimental investigations, a modelling study at the reactor scale is initiated to distinguish the influence of each process parameter. These models assume that the surface of adsorbent particles is continuously renewed by crystal growth. The aim of this work is to determine the decisive parameters which allow the

Low-level liquid waste decontamination by inorganic ion exchange

International Nuclear Information System (INIS)

Campbell, D.O.; Lee, D.D.; Dillow, T.A.

1990-01-01

Improved processes are being developed to treat contaminated liquid wastes that have been and continue to be generated at Oak Ridge National Laboratory. The most serious contaminants are 137 Cs and 90 Sr, and certain inorganic ion-exchange material have given promising results. Nickel and cobalt hexacyanoferrate (II) compounds are extremely selective for cesium removal, with distribution coefficients in excess of 10 6 even in the presence of high cesium and moderate potassium concentrations. Sodium titanate is selective for strontium removal from solutions with high alkali metal concentrations, especially at high pH. These separations are so efficient that one or two stages of simple, batch separation can yield large DFs (∼10 4 ) while still generating small volumes of solid waste

Combined methods for liquid radioactive waste treatment. Final report of a co-ordinated research project 1997-2001

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-02-01

The report contains 13 papers presented at the final research co-ordination meeting of the CRP. The subjects covered include processes and technologies for treatment and conditioning of liquid radioactive wastes. It quite often includes the application of several steps, such as filtration, precipitation, sorption, ion exchange, evaporation and/or membrane separation to meet the requirements both for the release of decontaminated effluents into the environment and the conditioning of waste concentrates for disposal. Combination of the processes and their consecutive or simultaneous application is also described. It results in an improved decontamination, waste volume reduction, safety and overall cost effectiveness in the treatment, conditioning and disposal of these wastes.

Combined methods for liquid radioactive waste treatment. Final report of a co-ordinated research project 1997-2001

International Nuclear Information System (INIS)

2003-02-01

The report contains 13 papers presented at the final research co-ordination meeting of the CRP. The subjects covered include processes and technologies for treatment and conditioning of liquid radioactive wastes. It quite often includes the application of several steps, such as filtration, precipitation, sorption, ion exchange, evaporation and/or membrane separation to meet the requirements both for the release of decontaminated effluents into the environment and the conditioning of waste concentrates for disposal. Combination of the processes and their consecutive or simultaneous application is also described. It results in an improved decontamination, waste volume reduction, safety and overall cost effectiveness in the treatment, conditioning and disposal of these wastes

The Assessment of Radioactive Liquid Waste Treatment Generated From The Fuel Reprocessing Plant Using Chemical Coagulation Method

International Nuclear Information System (INIS)

Kuncoro Arief, H; M Birmano, Dj

1998-01-01

Reprocessing of nuclear spent fuel produced 8 lot of radioactive liquid waste still bearing uranium and transuranium. The assessment of the radioactive liquid waste treatment with FeCI 3 as coagulant has been done. Decontamination factor and separation efficiency can be calculated from known activities of initial and post-treatment wastes. It can be concluded that some factors i.e. pH of treatment process, quantity of coagulant, mixing rate, and mixing time have influenced the treatment product

Melting decontamination and free release of metal waste at Studsvik RadWaste Co. in Sweden

International Nuclear Information System (INIS)

Kawatsuma, Shinji; Ishikawa, Keiji; Matsubara, Tatsuo; Donomae, Yasushi; Imagawa, Yasuhiro

2006-01-01

The Studsvik RadWaste Co. in Sweden was visited on August 29, 2005 by members of radioactive waste and decommissioning subgroup of central safety task force in old Japan Nuclear Cycle Development Institute as 'Overseas investigation'. The visit afforded us the chance to survey melting and decontaminating of metallic waste in this company and the status of free release. Domestic and foreign radioactive metallic waste is accepted in this company after 1987, and the majority of the decontaminated waste have been released freely. In the background of the big effort of this company and the strong leadership of the regulator (SSI: Swedish radiation protection Authority), prosperous operation was able to have been achieved. This survey was done based on 'Free release of radioactive metallic waste in Europe: the free release experience for 17 years at Studsvik RadWaste Co. in Sweden' by Dr. J. Lorenzen. (author)

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)

Sorption-reagent treatment of brines produced by reverse osmosis unit for liquid radioactive waste management

International Nuclear Information System (INIS)

Avramenko, V. A.; Zheleznov, V. V.; Sergienko, V. I.; Chizhevsky, I. Yu

2003-01-01

The results of the pilot plant tests (2002-2003) of the sorption-reagent decontamination of high salinity radioactive waste (brines) remaining after the low-salinity liquid radioactive waste (LRW) treatment in the reverse-osmosis unit from long-lived radionuclides are presented. The sorption-reagent materials used in this work were developed in the Institute of Chemistry FEDRAS. They enable one to decontaminate brines with total salt content up to 50 g/l from long-lived radionuclides of Cs, Sr and Co. At joint application of the reverse-osmosis and sorption-reagent technologies total volume of solid radioactive waste (SRW) decreases up to 100-fold as compared to the technology of cementation of reverse osmosis brines. In this case total cost of LRW treatment and SRW disposal decreases more than 10-fold. Brines decontaminated from radionuclides are then diluted down to the ecologically safe total salts content in water to be disposed of. Tests were performed to compare the efficiency of technologies including evaporation of brines remaining after reverse osmosis process and their decontamination by means of the sorption-reagent method. It was shown that, as compared to evaporation, the sorption-reagent technology provides substantial advantages as in regard to radioactive waste total volume reduction as in view of total cost of the waste management

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

International Nuclear Information System (INIS)

Deng Junxian; Li Xin; Hou Huijuan

2011-01-01

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

Design and construction of the low-level liquid waste treatment system

International Nuclear Information System (INIS)

Baker, M.N.; Mateer, W.E.; Metzler, G.H.; Reeves, S.R.; Rickettson, D.J.

1989-03-01

This report describes the design and construction of the Low-Level Liquid Waste Treatment System (LWTS). The LWTS is part of a system that will prepare High-Level Radioactive Waste for solidification in glass. This preparation includes removal of water and salts from the stored waste. The topics addressed are: the design objective to reuse the Process Building to contain LWTS, the special considerations that arise when building a new system inside a decontaminated facility, interface to existing plant systems, phased construction, and construction testing. 8 refs., 24 figs

Electropolishing decontamination system for high-level waste canisters

International Nuclear Information System (INIS)

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

1988-10-01

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

Investigations regarding the wet decontamination of fluorescent lamp waste using iodine in potassium iodide solutions

International Nuclear Information System (INIS)

Tunsu, Cristian; Ekberg, Christian; Foreman, Mark; Retegan, Teodora

2015-01-01

Highlights: • A wet-based decontamination process for fluorescent lamp waste is proposed. • Mercury can be leached using iodine in potassium iodide solution. • The efficiency of the process increases with an increase in leachant concentration. • Selective leaching of mercury from rare earth elements is achieved. • Mercury is furthered recovered using ion exchange, reduction or solvent extraction. - Abstract: With the rising popularity of fluorescent lighting, simple and efficient methods for the decontamination of discarded lamps are needed. Due to their mercury content end-of-life fluorescent lamps are classified as hazardous waste, requiring special treatment for disposal. A simple wet-based decontamination process is required, especially for streams where thermal desorption, a commonly used but energy demanding method, cannot be applied. In this study the potential of a wet-based process using iodine in potassium iodide solution was studied for the recovery of mercury from fluorescent lamp waste. The influence of the leaching agent’s concentration and solid/liquid ratio on the decontamination efficiency was investigated. The leaching behaviour of mercury was studied over time, as well as its recovery from the obtained leachates by means of anion exchange, reduction, and solvent extraction. Dissolution of more than 90% of the contained mercury was achieved using 0.025/0.05 M I 2 /KI solution at 21 °C for two hours. The efficiency of the process increased with an increase in leachant concentration. 97.3 ± 0.6% of the mercury contained was dissolved at 21 °C, in two hours, using a 0.25/0.5 M I 2 /KI solution and a solid to liquid ratio of 10% w/v. Iodine and mercury can be efficiently removed from the leachates using Dowex 1X8 anion exchange resin or reducing agents such as sodium hydrosulphite, allowing the disposal of the obtained solution as non-hazardous industrial wastewater. The extractant CyMe 4 BTBP showed good removal of mercury, with an

Investigations regarding the wet decontamination of fluorescent lamp waste using iodine in potassium iodide solutions

Energy Technology Data Exchange (ETDEWEB)

Tunsu, Cristian, E-mail: tunsu@chalmers.se; Ekberg, Christian; Foreman, Mark; Retegan, Teodora

2015-02-15

Highlights: • A wet-based decontamination process for fluorescent lamp waste is proposed. • Mercury can be leached using iodine in potassium iodide solution. • The efficiency of the process increases with an increase in leachant concentration. • Selective leaching of mercury from rare earth elements is achieved. • Mercury is furthered recovered using ion exchange, reduction or solvent extraction. - Abstract: With the rising popularity of fluorescent lighting, simple and efficient methods for the decontamination of discarded lamps are needed. Due to their mercury content end-of-life fluorescent lamps are classified as hazardous waste, requiring special treatment for disposal. A simple wet-based decontamination process is required, especially for streams where thermal desorption, a commonly used but energy demanding method, cannot be applied. In this study the potential of a wet-based process using iodine in potassium iodide solution was studied for the recovery of mercury from fluorescent lamp waste. The influence of the leaching agent’s concentration and solid/liquid ratio on the decontamination efficiency was investigated. The leaching behaviour of mercury was studied over time, as well as its recovery from the obtained leachates by means of anion exchange, reduction, and solvent extraction. Dissolution of more than 90% of the contained mercury was achieved using 0.025/0.05 M I{sub 2}/KI solution at 21 °C for two hours. The efficiency of the process increased with an increase in leachant concentration. 97.3 ± 0.6% of the mercury contained was dissolved at 21 °C, in two hours, using a 0.25/0.5 M I{sub 2}/KI solution and a solid to liquid ratio of 10% w/v. Iodine and mercury can be efficiently removed from the leachates using Dowex 1X8 anion exchange resin or reducing agents such as sodium hydrosulphite, allowing the disposal of the obtained solution as non-hazardous industrial wastewater. The extractant CyMe{sub 4}BTBP showed good removal of mercury

Liquid radwaste treatment by microfiltration, ultrafiltration and reverse osmosis

International Nuclear Information System (INIS)

Dulama, M.; Deneanu, N.; Popescu, I.V.

2001-01-01

Radioactive liquid waste processing is an integral part of any facility involved in nuclear power generation, radioisotope production, research and development, decontamination or other aspects of nuclear energy. The aqueous liquid radwastes from the decontamination center are currently treated by the membrane plant. Generally, the liquid waste streams are effectively volume-reduced by a combination of continuous crossflow microfiltration (MF), spiral wound reverse osmosis (SWRO) and tubular reverse osmosis membrane technologies. Backwash chemical cleaning wastes from the membrane plant are further volume-reduced by evaporation. The concentrate from the membrane plant is ultimately immobilized with bitumen. We performed experiments using two simulated waste solution; secondary waste from the decontamination process with POD (Permanganate Oxidation Decontamination) solution and secondary waste from decontamination with CAN-DECON solution. The experimental tests have been done with cellulose acetate (CA) membrane and polysulfonate (PSF) membrane manufactured at Research Center for Macromolecular Materials and Membranes Bucharest and with Millipore membrane type VS 0.025 μm. A schematic of the laboratory-scale test facility is presented

Dry blasting decontaminating method for radioactive waste

International Nuclear Information System (INIS)

Nishiwaki, Hitoshi.

1993-01-01

In the present invention, when abrasives are dry blasted on the surface of radioactive wastes and the recovered abrasives are classified for re-use, abrasives having a microvicker's hardness (HMV) of greater than 600 and a grain size of greater than 1mm are used in a case where the radioactive wastes to be abraded are stainless steels. This enables dry blasting decontamination for stainless steels which has been considered to be impossible. In addition since the amount of secondary wastes are reduced, it is extremely effective. (T.M.)

Decontamination of irradiated-fuel processing waste using manganese dioxide hydrate

International Nuclear Information System (INIS)

Auchapt, J.M.; Gaudier, J.F.

1969-01-01

The 'manganese dioxide' process is designed to replace the 'calcium carbonate' treatment for low and medium activity wastes. The objective to attain during the research for a new process was the diminution of the volume of the sludge without decreasing the decontamination factor of the wastes. The new process involves addition in series of twice over 100 ppm of Mn 2+ in the waste which has previously been made basic and oxidizing; the precipitate formed in situ is separated after each addition. The process has the advantage of increasing the decontamination of strontium. The treatment can be used in a plant including two decantation units and has given effective results when applied in such a plant. (author) [fr

Solid waste handling and decontamination facility

International Nuclear Information System (INIS)

Lampton, R.E.

1979-01-01

The Title 1 design of the decontamination part of the SWH and D facility is underway. Design criteria are listed. A flowsheet is given of the solid waste reduction. The incinerator scrubber is described. Design features of the Gunite Tank Sludge Removal and a schematic of the sluicer, TV camera, and recirculating system are given. 9 figures

Decontamination method for radiation-contaminated metal waste

International Nuclear Information System (INIS)

Suwa, Takeshi; Kuribayashi, Nobuhide; Yasumune, Taketoshi.

1991-01-01

In immersing radiation-contaminated metal wastes into a sulfuric acid solution thereby peeling and removing radioactive deposition cruds and dissolving the surface of the matrix metals to eliminate radioactive contaminants, when the potential of the sulfuric acid solution is shifted to a higher direction by more than a certain level due to the increase of the amount of metal ions leached from the cruds and the matrix material, the leached metal ions are electrolytically reduced to control the potential of the sulfuric acid solution to less than a predetermined potential level. Although the dissolving rate is increased as the concentration of the sulfuric acid solution is higher, it is preferably from 0.5 to 2 mol/l, since higher concentration increases the load on the waste liquid processing. Further, the temperature for solution is set to higher than a room temperature and, preferably from 50 to 90degC. Further, the potential level of the solution, although varies somewhat depending on the concentration of the leached metal ions and the temperature, is preferably controlled to less than 0.1 to 0.2 V. This can attain high decontaminating effect in a short period of time by using a sulfuric acid solution alone. (T.M.)

Experimental tests performed with liquid waste contained in the tank F-710/D at EUREX plant

International Nuclear Information System (INIS)

Gasso, G.; Momo, S.; Pietrelli, L.; Troiani, F.

1989-11-01

In this report the result of experimental test performed with real liquid waste earning from reprocessing of MTR nuclear fuel is reported. The aim of the research is to separate the actinides and long-lived radioactive fission products from bulk salt matrix of HLW. Taking into account the chemical and radiochemical composition of the liquid waste, process based on the chemical precipitation and/or adsorption were studied by using the radioactive waste sampled from the tank. The results show that decontamination factors of 100, 1000, 5000 were obtained for Sr, Cs and Pu respectively. (author)

Understanding Mechanism of Photocatalytic Microbial Decontamination of Environmental Wastewater

Directory of Open Access Journals (Sweden)

Chhabilal Regmi

2018-02-01

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

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.)

Decontamination of alpha-bearing solid wastes and plutonium recovery

International Nuclear Information System (INIS)

Koehly, G.; Madic, C.; Lecomte, M.; Bourges, J.; Saulze, J.L.; Broudic, J.C.

1993-01-01

Nuclear activities in the Radiochemistry building of Fontenay-aux-Roses Nuclear Research Center concern principally the study of fuel reprocessing and the production of transuranium isotopes. During these activities solid wastes are produced. In order to improve the management of these wastes, it has been decided to build new facilities: a group of three glove-boxes named ELISE for the treatment of α active solid waste and a hot-cell, PROLIXE, for the treatment of solid wastes. Leaching processes were developed in order to: decontaminate these wastes and recover actinide elements, particularly the highly valuable plutonium, from the leachates. The processes developed are sufficiently flexible to be able to accommodate solid wastes produced in other facilities. Laboratory studies were conducted to develop the leaching process based on the use of electrogenerated Ag(II) species which is particularly suitable to provoke the dissolution of PuO 2 . Successful exhaustive Pu decontaminations with DF(Pu) higher than 10 4 were achieved for the first time during the treatment of stainless steel PuO 2 cans (future MELOX plant) by electrogenerated Ag (II) in nitric acid medium

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

International Nuclear Information System (INIS)

Muller, H.M.

1984-01-01

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

Decontamination of waste radioactive polluted solutions in radiation treatment

International Nuclear Information System (INIS)

Simova, G.; Boyadzhiev, A.; Mikhajlov, M.G.; Shopov, N.

1979-01-01

The decontamination capacity of solutions of the trivial cleaning Bulgarian preparations ''Mipro'', ''Sana'', ''Synthek'' and ''Univer'' for different surfaces (steel, glass, PVC and linoleum) contaminated with cesium-134, strontium-85 or cerium-144 chlorides, was studied. Concentrations from 5 to 15 g/l of the solutions used in this study displayed a degree of cleaning over 90%. Higher concentration of the solution does not improve its cleaning capacity. For evaluation of foam formation by the solutions, the so called ''foam column stability coefficient'' has been adopted. This coefficient represents the ratio between the height of the foam column and the time of its half life, referred to the time for the foam column formation when blown through with a constant air current. On the basis of this index, solutions of the preparation ''Mipro'' proved to be the best ones for decontamination - in the whole investigated concentration span, the foam column stability coefficient for the solutions of this preparation is with two orders lower than the respective coefficient of the other preparations. It was experimentally established that radiation treatment of radio-contaminated solutions reduces the foam column stability coefficient. Radiation treatment should be carried out in a gamma field, realizing at least one megarad within an acceptable for the liquid wastes time period. (A.B.)

Depressurized pipes decontamination by using circulation foam

International Nuclear Information System (INIS)

Damerval, Frederique; Belz, Jacques; Renouf, Marjorie; Janneau, Patrice

2012-09-01

Decontamination of pipes remains a necessity in order to reduce the radiation level during maintenance or dismantling operations but it is not so easy to do it, especially in case of a long pipe network. To achieve this operation, the use of chemistry is one of the more relevant methods; moreover, the liquid waste production still remains an issue that it can be avoided by the use of decontamination foams. (authors)

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

Research and development on low level liquid waste treatment in Thailand

International Nuclear Information System (INIS)

Yamkate, P.; Sinakhom, F.; Punnachaiya, M.; Chantaraprachoom, N.; Srisorn, S.

1996-01-01

The studies have been directed towards several subjects concerning the treatment technologies of low level waste. The simple physico-chemical method has been studied for applying to many kind of waste streams such as reactor waste, isotope production waste and liquid waste from the hospital. The characterization of inorganic ion-exchangers including the effect of pH, equilibrium time, temperature and concentration of such ion-exchangers were tested and the optimum condition of the sorption of C x on the exchangers are reported. The results from the investigation on the efficiencies of detergents in the radioactive decontamination reveal that the local simple brand machine-washed detergents. which is very cheap, can be best used as the decontaminating agent instead of the more expensive imported one. It is found that chemical precipitation methods i.e. phosphate coagulation, copper ferrocyanide coagulation and cobalt precipitation method can be used for treating of the waste stream arising successfully. In considering of the immobilizing process of treated waste, cementation is advised to be used and, therefore, subjects to be evaluated. The basic properties of cement-waste products as well the leachability of a particular types of sludge waste at 15-40% waste loading were investigated. The result reveals that, cement waste forms of inorganic ion-exchanger and of sludge waste from chemical precipitation of decontamination waste, exhibit high compressive strength and a low leach rates. The compressive strength of 118-207 Kg/cm 2 were found for the optimum waste products originated from various exchangers and 15-20% loading of sludge waste. The leachability of Co-60, Cs-134 and Sr-85 from 15-40% loading of cement waste for 30 days were studied. The cumulative fraction leached rate of Cs-134 from sludge-cement wastes was found to be about 17 x 10 - 3 g/cm 2 for 25 degree C and 50 degree C at 30 days leaching time respectively, while there were no leaching of Sr-85 and

Basic study on decontamination of TRU wastes with cerium mediated electrolytic oxidation method

International Nuclear Information System (INIS)

Ishii, Junichi; Kobayashi, Fuyumi; Uchida, Shoji; Sumiya, Masato; Kida, Takashi; Shirahashi, Koichi; Umeda, Miki; Sakuraba, Koichi

2010-03-01

At Nuclear Fuel Cycle Safety Engineering Research Facility (NUCEF), the cerium mediated electrolytic oxidation method which is a decontamination technique to decrease the radioactivity of TRU wastes to the clearance-level has been developed for the effective reduction of TRU wastes generated from the decommissioning of a nuclear fuel reprocessing facility and so on. This method corrodes the oxide layer and the surface of metallic TRU metal wastes by the strong oxidation power of Ce 4+ in nitric acid. In this study, parameter tests were conducted to optimize the solution condition of Ce 3+ initial concentrations and nitric acid concentrations. The target corrosion rate of metallic TRU wastes set to be 2 - 4 μm/h for the practical use of this method. Under the optimized solution condition, a dissolution test of stainless steel simulating wastes was carried out. From the result of the dissolution test, the average corrosion rate was 3.3 μm/h during the test time of 90 hours. Based on the supposition that the corrosion depth of metallic TRU wastes was 20 μm enough to achieve the clearance-level, the treatment time for the decontamination was about 6 hours. It was confirmed from the result that the decontamination could be performed within one day and the decontamination solution could repeatedly reuse 15 times. (author)

Actinide partitioning from high level liquid waste using the Diamex process

International Nuclear Information System (INIS)

Madic, C.; Blanc, P.; Condamines, N.; Baron, P.; Berthon, L.; Nicol, C.; Pozo, C.; Lecomte, M.; Philippe, M.; Masson, M.; Hequet, C.

1994-01-01

The removal of long-lived radionuclides, which belong to the so-called minor actinides elements, neptunium, americium and curium, from the high level nuclear wastes separated during the reprocessing of the irradiated nuclear fuels in order to transmute them into short-lived nuclides, can substantially decrease the potential hazards associated with the management of these nuclear wastes. In order to separate minor actinides from high-level liquid wastes (HLLW), a liquid-liquid extraction process was considered, based on the use of diamide molecules, which display the property of being totally burnable, thus they do not generate secondary solid wastes. The main extracting properties of dimethyldibutyltetradecylmalonamide (DMDBTDMA), the diamide selected for the development of the DIAMEX process, are briefly described in this paper. Hot tests of the DIAMEX process (using DMDBTDMA) related to the treatment of an mixed oxide fuels (MOX) type HLLW, were successfully performed. The minor actinide decontamination factors of the HLLW obtained were encouraging. The main results of these tests are presented and discussed in this paper. (authors). 9 refs., 2 figs., 7 tabs

Retrofit design of remotely removable decontamination spray nozzles for the new waste calcining facility at the Idaho National Engineering Laboratory

International Nuclear Information System (INIS)

Gay, J.A.

1988-01-01

High level radioactive liquid waste is converted to a solid form at the Idaho Chemical Processing Plant (ICPP). The conversion is done by a fluidized bed combustion process in the calciner vessel. The interior decontamination system for the calciner vessel uses a common header bolted to four decontamination nozzles around the upper head. The retrofit was required to eliminate hands-on maintenance and difficulty in nozzle removal because of nozzle plugging. The retrofit design for this project demonstrates the solution of problems associated with thermal phenomena, structural supports, seismic requirements, remote handling and installations into extremely restricted spaces

Investigations regarding the wet decontamination of fluorescent lamp waste using iodine in potassium iodide solutions.

Science.gov (United States)

Tunsu, Cristian; Ekberg, Christian; Foreman, Mark; Retegan, Teodora

2015-02-01

With the rising popularity of fluorescent lighting, simple and efficient methods for the decontamination of discarded lamps are needed. Due to their mercury content end-of-life fluorescent lamps are classified as hazardous waste, requiring special treatment for disposal. A simple wet-based decontamination process is required, especially for streams where thermal desorption, a commonly used but energy demanding method, cannot be applied. In this study the potential of a wet-based process using iodine in potassium iodide solution was studied for the recovery of mercury from fluorescent lamp waste. The influence of the leaching agent's concentration and solid/liquid ratio on the decontamination efficiency was investigated. The leaching behaviour of mercury was studied over time, as well as its recovery from the obtained leachates by means of anion exchange, reduction, and solvent extraction. Dissolution of more than 90% of the contained mercury was achieved using 0.025/0.05 M I2/KI solution at 21 °C for two hours. The efficiency of the process increased with an increase in leachant concentration. 97.3 ± 0.6% of the mercury contained was dissolved at 21 °C, in two hours, using a 0.25/0.5M I2/KI solution and a solid to liquid ratio of 10% w/v. Iodine and mercury can be efficiently removed from the leachates using Dowex 1X8 anion exchange resin or reducing agents such as sodium hydrosulphite, allowing the disposal of the obtained solution as non-hazardous industrial wastewater. The extractant CyMe4BTBP showed good removal of mercury, with an extraction efficiency of 97.5 ± 0.7% being achieved in a single stage. Better removal of mercury was achieved in a single stage using the extractants Cyanex 302 and Cyanex 923 in kerosene, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

International Nuclear Information System (INIS)

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

2008-01-01

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

Effluent treatment plant and decontamination centre, Trombay

International Nuclear Information System (INIS)

Kaushik, C.P.; Agarwal, K.

2017-01-01

The Bhabha Atomic Research Centre, Trombay, has a number of plants and laboratories, which generate Radioactive Liquid Waste and Protective Wears. Two facilities have been established in late 1960s to cater to this requirement. The Centre, on the average generates about 50,000 m"3 of active liquid effluents of varying specific activities. The Effluent Treatment Plant was setup to receive and process radioactive liquids generated by various facilities of BARC in Trombay. It also serves a single-point discharge facility to enable monitoring of radioactive effluents discharged from the Trombay site. About 120-150 Te of protective wears and inactive apparel are generated annually from various radioactive facilities and laboratories of BARC. In addition, contaminated fuel assembly components are generated by DHRUVA and formerly by CIRUS. These components require decontamination before its recycle to the fuel assembly process. The Decontamination Centre, setup in late 1960s, is mandated to carry out the above mentioned decontamination activities

Technology for treatment of decontamination products

International Nuclear Information System (INIS)

Kavkhuta, G.A.; Rozdzyalovskaya, L.F.

1994-01-01

The research concerning the methods of management and processing of products generated as the result of post Chernobyl decontamination activities is being carried out by the Institute of Radioecological Problems of Belarus Academy of Science (IRP) in the framework of the Belarus National Programme. The main goal of this work is choice and development of an appropriate system for treatment of the decontamination radwastes, based on currently available information and experimental studies. This paper presents the technological schemes being studied for treating the post-Chernobyl liquid and solid wastes and will also briefly discuss the approach being used to settle a problem on collecting/management of low-level radioactive ash wastes, generated from the use of contaminated fuel

Decontamination process applied to radioactive solid wastes from nuclear power plants

International Nuclear Information System (INIS)

Franco, Milton B.; Kastner, Geraldo F.; Monteiro, Roberto Pellacani G.

2009-01-01

The process of decontamination is an important step in the economic operation of nuclear facilities. A large number of protective clothing, metallic parts and equipment get contaminated during the handling of radioactive materials in laboratory, plants and reactors. Safe and economic operation of these nuclear facilities will have a bearing on the extent to which these materials are reclaimed by the process of decontamination. The most common radioactive contaminants are fission products, corrosion products, uranium and thorium. The principles involved in decontamination are the same as those for an industrial cleaning process. However, the main difference is in the degree of cleaning required and at times special techniques have to be employed for removing even trace quantities of radioactive materials. This paper relate decontaminations experiences using acids and acids mixtures (HCl, HF, HNO 3 , KMnO 4 , C 2 H 2 O 4 , HBF 4 ) in several kinds of radioactive solid wastes from nuclear power plants. The result solutions were monitored by nuclear analytical techniques, in order to contribute for radiochemical characterization of these wastes. (author)

TRU-waste decontamination and size reduction review, June 1983, US DOE/PNC technology exchange

International Nuclear Information System (INIS)

Becker, G.W. Jr.

1983-01-01

A review of transuranic (TRU) noncombustible waste decontamination and size reduction technology is presented. Electropolishing, vibratory cleaning, and spray decontamination processes developed at Battelle Pacific Northwest Laboratory (PNL) and Savannah River Laboratory (SRL) are highlighted. TRU waste size reduction processes at (PNL), Los Alamos National Laboratory (LANL), the Rocky Flats Plant (RFP), and SRL are also highlighted

Health physics challenges during decontamination for safe disposal of low level liquid effluent tank as inactive scrap

International Nuclear Information System (INIS)

Akila, R.; Sultan, Bajeer; Sarangapani, R.; Jose, M.T.

2018-01-01

The Low-level Liquid waste (LLW) generated during the regeneration of mixed bed column of KAMINI reactor is collected in the SS Delay Tanks located on the western side of RML building. It was proposed to dismantle and dispose the tank as solid waste. The tank weighs about 2 ton. An attempt was made to decontaminate the tank to levels below the exempt quantity so as to qualify it as scrap of unrestricted release. This is first time in IGCAR wherein a material used in a radioactive facility for storing LLW is being released as scrap of unrestricted release and this paper discusses about the same

Estimation and characterization of decontamination and decommissioning solid waste expected from the Plutonium Finishing Plant

International Nuclear Information System (INIS)

Millar, J.S.; Pottmeyer, J.A.; Stratton, T.J.

1995-01-01

Purpose of the study was to estimate the amounts of equipment and other materials that are candidates for removal and subsequent processing in a solid waste facility when the Hanford Plutonium Finishing Plant is decontaminated and decommissioned. (Building structure and soil are not covered.) Results indicate that ∼5,500 m 3 of solid waste is expected to result from the decontamination and decommissioning of the Pu Finishing Plant. The breakdown of the volumes and percentages of waste by category is 1% dangerous solid waste, 71% low-level waste, 21% transuranic waste, 7% transuranic mixed waste

Decontamination of organic waste

International Nuclear Information System (INIS)

Schulz, W.

1977-01-01

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

Decontamination processes for low level radioactive waste metal objects

International Nuclear Information System (INIS)

Longnecker, E.F.; Ichikawa, Sekigo; Kanamori, Osamu

1996-01-01

Disposal and safe storage of contaminated nuclear waste is a problem of international scope. Although the greatest volume of such waste is concentrated in the USA and former Soviet Union, Western Europe and Japan have contaminated nuclear waste requiring attention. Japan's radioactive nuclear waste is principally generated at nuclear power plants since it has no nuclear weapons production. However, their waste reduction, storage and disposal problems may be comparable to that of the USA on an inhabited area basis when consideration is given to population density where Japan's population, half that of the USA, lives in an area slightly smaller than that of California's. If everyone's backyard was in California, the USA might have insoluble radioactive waste reduction, storage and disposal problems. Viewing Japan's contaminated nuclear waste as a national problem requiring solutions, as well as an economic opportunity, Morikawa began research and development for decontaminating low level radioactive nuclear waste seven years ago. As engineers and manufacturers of special machinery for many years Morikawa brings special electro/mechanical/pneumatic Skills and knowledge to solving these unique problems. Genden Engineering Services and Construction Company (GESC), an affiliate of Japan Atomic Power Company, recently joined with Morikawa in this R ampersand D effort to decontaminate low level radioactive nuclear waste (LLW) and to substantially reduce the volume of such nuclear waste requiring long term storage. This paper will present equipment with both mechanical and chemical processes developed over these several years by Morikawa and most recently in cooperation with GESC

DWTF [decontamination and waste treatment facilities] assessment

International Nuclear Information System (INIS)

Maimoni, A.

1986-01-01

The purpose of this study has been to evaluate the adequacy of present and proposed decontamination and waste treatment facilities (DWTF) at LLNL, to determine the cost effectiveness for proposed improvements, and possible alternatives for accomplishing these improvements. To the extent possible, we have also looked at some of the proposed environmental compliance and cleanup (ECC) projects

Developing technique for waste water cleaning of a division for equipment decontamination

International Nuclear Information System (INIS)

Gromoglasov, A.A.; Solyakov, V.K.; Novikov, V.N.; Pil'shchikov, A.P.; Chekalov, A.G.; Sinyukov, M.A.; Pshenichnykh, V.N.

1989-01-01

Results are described of developing technique for radionuclide cleaning solutions after metal product decontamination. The method is based on the adagulation with usage of quicklime. The conclusion is method permits to consider it as the main technique for waste water decontamination. 3 refs.; 2 figs.; 3 tabs

Analysis of waste management issues arising from a field study evaluating decontamination of a biological agent from a building.

Science.gov (United States)

Lemieux, P; Wood, J; Drake, J; Minamyer, S; Silvestri, E; Yund, C; Nichols, T; Ierardi, M; Amidan, B

2016-01-01

The Bio-response Operational Testing and Evaluation (BOTE) Project was a cross-government effort designed to operationally test and evaluate a response to a biological incident (release of Bacillus anthracis [Ba] spores, the causative agent for anthrax) from initial public health and law enforcement response through environmental remediation. The BOTE Project was designed to address site remediation after the release of a Ba simulant, Bacillus atrophaeus spp. globigii (Bg), within a facility, drawing upon recent advances in the biological sampling and decontamination areas. A key component of response to a biological contamination incident is the proper management of wastes and residues, which is woven throughout all response activities. Waste is generated throughout the response and includes items like sampling media packaging materials, discarded personal protective equipment, items removed from the facility either prior to or following decontamination, aqueous waste streams, and materials generated through the application of decontamination technologies. The amount of residual contaminating agent will impact the available disposal pathways and waste management costs. Waste management is an integral part of the decontamination process and should be included through "Pre-Incident" response planning. Overall, the pH-adjusted bleach decontamination process generated the most waste from the decontamination efforts, and fumigation with chlorine dioxide generated the least waste. A majority of the solid waste generated during pH-adjusted bleach decontamination was the nonporous surfaces that were removed, bagged, decontaminated ex situ, and treated as waste. The waste during the two fumigation rounds of the BOTE Project was associated mainly with sampling activities. Waste management activities may represent a significant contribution to the overall cost of the response/recovery operation. This paper addresses the waste management activities for the BOTE field test

Study of decontamination and waste management technologies for contaminated rural and forest environment

International Nuclear Information System (INIS)

Grebenkov, A.; Davydchuk, V.; Firsakova, S.; Jouve, A.; Kutlakhmedov, Y.; Rose, K.; Zhouchenko, T.; Antzypaw, G.

1996-01-01

Pilot and demonstrative scale in situ trials of several decontamination technologies proposed in the framework of ECP-4 project were carried out in real conditions of Chernobyl Zone. Their results proved that industrial scale decontamination of various types of land is feasible. The management of radioactive waste arising from decontamination techniques can be provided by ecologically sound and efficient technologies

Final remediation of the provisional storage near Zavratec. Separation of waste, decontamination and radiological measurements

International Nuclear Information System (INIS)

Stepisnik, M.; Zeleznik, N.; Mele, I.

2000-01-01

This paper presents remedial activities in Zavratec during winter 1999 - 2000. The difficult and slow process of separation radioactive from non-radioactive waste is explained, and the measuring techniques and equipment for separation are presented. The measurements of storage contamination and its decontamination, involving different practical problems, are described in detail. As a result, the initial volume of the waste was reduced to 50%, in spite of the extended decontamination works. The waste has been relocated to the Brinje storage facility. Measurements inside and outside the Zavratec facility after decontamination showed that no radioactivity higher than the natural background was present. The facility was released for unrestricted use. (author)

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.

An Applied Study on the Decontamination and Decommissioning of Hot Cell Facilities in the United States and Comparison with the Studsvik Facility for Solid and Liquid Waste

International Nuclear Information System (INIS)

Varley, Geoff; Rusch, Chris

2006-07-01

This report presents the plans, processes and results of the decontamination and decommissioning of the Hot Cell Facility in Building 23 at the General Atomics Torrey Pines Mesa Facility (HCF) and compares the program and cost of decommissioning HCF with the Swedish cost estimate for decontamination and decommissioning of the HM hot cell and wastes treatment facility at Studsvik in Sweden. The HCF had three main hot cells and was licensed to: Receive, handle and ship radioactive materials; Remotely handle, examine and store irradiated fuel materials; Extract tritium (engineering scale); Support new reactor production development; Develop, fabricate and inspect UO 2 - BeO fuel materials. The HM facility in Studsvik was constructed to handle and package medium-active solid and liquid wastes, prior to disposal. Central to the facility is a conventional hot cell including three work stations, serviced by master slave manipulators. Other parts of the facility include holding tanks for liquid wastes and slurries, a centrifuge room, as well as an encapsulation station where drummed wastes can be encapsulated in cement, offices, laboratories and workshops and so on, as well as building and cell ventilation systems. Decontamination and decommissioning of the HCF took place during 1993 through 2001. The objective was to obtain regulatory release of the site so that it could be used on an unrestricted basis. Based on data from extensive hazardous and radiological materials characterization, GA evaluated four decommissioning options and selected dismantling as the only option that would satisfy the decommissioning objective. The decontamination and decommissioning scope included the following actions. 1. Remove the legacy waste that consisted of radioactive wastes stored at the HCF consisting of 21,434 kg of irradiated fuel material (IFM) that was owned by the US DoE and store the waste in temporary storage set up at the GA site. 2. Actual Decontamination and Dismantlement

An Applied Study on the Decontamination and Decommissioning of Hot Cell Facilities in the United States and Comparison with the Studsvik Facility for Solid and Liquid Waste

Energy Technology Data Exchange (ETDEWEB)

Varley, Geoff; Rusch, Chris [NAC International, Atlanta, GA (United States)

2006-07-15

This report presents the plans, processes and results of the decontamination and decommissioning of the Hot Cell Facility in Building 23 at the General Atomics Torrey Pines Mesa Facility (HCF) and compares the program and cost of decommissioning HCF with the Swedish cost estimate for decontamination and decommissioning of the HM hot cell and wastes treatment facility at Studsvik in Sweden. The HCF had three main hot cells and was licensed to: Receive, handle and ship radioactive materials; Remotely handle, examine and store irradiated fuel materials; Extract tritium (engineering scale); Support new reactor production development; Develop, fabricate and inspect UO{sub 2} - BeO fuel materials. The HM facility in Studsvik was constructed to handle and package medium-active solid and liquid wastes, prior to disposal. Central to the facility is a conventional hot cell including three work stations, serviced by master slave manipulators. Other parts of the facility include holding tanks for liquid wastes and slurries, a centrifuge room, as well as an encapsulation station where drummed wastes can be encapsulated in cement, offices, laboratories and workshops and so on, as well as building and cell ventilation systems. Decontamination and decommissioning of the HCF took place during 1993 through 2001. The objective was to obtain regulatory release of the site so that it could be used on an unrestricted basis. Based on data from extensive hazardous and radiological materials characterization, GA evaluated four decommissioning options and selected dismantling as the only option that would satisfy the decommissioning objective. The decontamination and decommissioning scope included the following actions. 1. Remove the legacy waste that consisted of radioactive wastes stored at the HCF consisting of 21,434 kg of irradiated fuel material (IFM) that was owned by the US DoE and store the waste in temporary storage set up at the GA site. 2. Actual Decontamination and

Nuclear engineering questions: power, reprocessing, waste, decontamination, fusion

International Nuclear Information System (INIS)

Walton, R.D. Jr.

1979-01-01

This volume contains papers presented at the chemical engineering symposium on nuclear questions. Specific questions addressed by the speakers included: nuclear power - why and how; commercial reprocessing - permanent death or resurrection; long-term management of commercial high-level wastes; long-term management of defense high-level waste; decontamination and decommissioning of nuclear facilities, engineering aspects of laser fusion I; and engineering aspects of laser fusion II. Individual papers have been input to the Energy Data Base previously

Waste management aspects of entire PWR LOOP decontamination

International Nuclear Information System (INIS)

Murray, A.P.; Roesmer, J.

1988-01-01

The waste management parameters for decontamination of an entire PWR primary circuit have been determined for dilute alkaline-permanganate/citric acid (APCA), LOMI, ozone and cerium acid process variations. APCA processes generate the largest waste volumes; over 140 m 3 (5000 ft 3 ) in some cases. This represents a potential disposal cost of one million dollars. The cation regeneration column makes the greatest contribution to the disposal volume. In contrast, the LOMI process generates approximately half as much waste, but it is expected to contain relatively high metal concentrations (200-800 ppm). The ozone and cerium acid processes product the least waste, usually under 45 m 3 . These waste volume estimates represent considerable fractions of a utility's annual disposal volume. Consequently, improved waste processing technology is required, and several approaches are suggested

Application of reverse osmosis membrane technology for liquid radioactive waste processing

International Nuclear Information System (INIS)

Zhao Juan

2010-01-01

Liquid radioactive waste (LRW) processing should bear an acceptable level of residual radioactivity for discharge and meet the request of energy saving and waste minimization. Reverse osmosis (RO) membrane technology has been developed as a novel process for LRW processing. Five basic operating parameters of flux, recovery factor, rejection factor, concentration factor and decontamination factor were described, and the latter two parameters were the most important. Concentration factor and decontamination factor should be as high as possible and simultaneously the operating cost for membrane filtration should be low. Technical design considerations for membrane process were discussed and optimized from the aspects of pretreatment, membrane module choice and arrangement and membrane clear out. Application and investigation of RO membrane technology for LRW processing were introduced and it should be noted that the RO membrane technology has been introduced into overseas nuclear power plants for LRW processing and interiorly in the stage of investigation. (authors)

Forming of information support for estimate of potential danger of storage points of the decontamination wastes

International Nuclear Information System (INIS)

Skurat, V.V.; Shiryaeva, N.M.; Myshkina, N.K.; Gvozdev, A.A.; Serebryannyj, G.Z.; Golikova, N.B.

2002-01-01

By now 92 storage points of the decontamination wastes that formed in result of decontamination of settlements after the Chernobyl accident is registered on the territory of Belarus. The most of theirs were placed in the unfavorable for storage of radioactive wastes places. It was examine the forming of information support for estimate of potential danger of the storage points of decontamination wastes that base on results of investigations of objects, field and laboratory investigations, theoretical researches, using of literary information about features of radionuclides migration through engineering and natural barriers to water-bearing horizon is examination

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)

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

Basic design of alpha aqueous waste treatment process in NUCEF

Energy Technology Data Exchange (ETDEWEB)

Mineo, Hideaki; Matsumura, Tatsuro; Nishizawa, Ichio; Mitsui, Takeshi; Ueki, Hiroyuki; Wada, Atsushi; Sakai, Ichita; Takeshita, Isao [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Nishimura, Kenji

1996-11-01

This paper described the basic design of Alpha Aqueous Waste Treatment Process in NUCEF. Since various experiments using the TRU (transuranium) elements are carried out in NUCEF, wastes containing TRU elements arise. The liquid wastes in NUCEF are categorized into three types. Decontamination and volume reduction of the liquid waste mainly of recovery water from acid recovery process which has lowest radioactive concentration is the most important task, because the arising rate of the waste is large. The major function of the Alpha Aqueous Waste Treatment Process is to decontaminate the radioactive concentration below the level which is allowed to discharge into sea. Prior the process design of this facility, the followings are evaluated:property and arising rate of the liquid waste, room space to install and licensing condition. Considering varieties of liquid wastes and their large volume, the very high decontamination factor was proposed by a process of multiple evaporation supported with filtration and adsorption in the head end part and reverse osmosis in the distillate part. (author)

Investigation on safety of gel decontamination technology

International Nuclear Information System (INIS)

Liu Zhihui; Song Fengli; Wang Yongxian; Zhang Taoge

2014-01-01

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

Advanced evaporation/concentration treatment technology for radioactive liquid waste

International Nuclear Information System (INIS)

Zhang Zhijian; Lu Zhiming; Yu Ruixia

1997-01-01

A new and effective two stage moisture separator which removes remaining water droplet and free ion in secondary steam can be added between the evaporator and the condenser of existing liquid waste treatment system. Its addition increases decontamination factor to more than ten times. Ion content in condensed water is decreased considerably. Condensed water meets emission standard without passing through ion exchanger. Detail fundamentals are analysed and results are given: (1) system diagram, (2) structure sketch of the two stage moisture separator, (3) laboratory test results

Assessment of radiological properties of wastes from urban decontamination procedures

International Nuclear Information System (INIS)

Da Silva, D.N.G.; Guimarães, J.R.D.; Rochedo, E.R.R.; Rochedo, P.R.R.; De Luca, C.

2015-01-01

One important activity associated to urban areas contaminated from accidental releases to the atmosphere of nuclear power plants is the management of radioactive wastes generated from decontamination procedures. This include the collection, conditioning, packing, transport and temporary/final disposition. The final destination is defined usually through a political decision. Thus, transport of packed radioactive wastes shall depend on decisions not just under the scope of radiological protection issues. However, the simulations performed to assess doses for the public and decontamination workers allows the estimate of radiological aspects related to the waste generated and these characteristics may be included in a multi-criteria decision tool aiming to support, under the radiological protection point of view, the decision-making process on post-emergency procedures. Important information to decision makers are the type, amount and activity concentration of wastes. This work describes the procedures to be included in the urban area model to account for the assessment of qualitative and quantitative description of wastes. The results will allow the classification of different procedures according to predefined criteria that shall then feed the multi-criteria assessment tool, currently under development, considering basic radiological protection aspects of wastes generated by the different available cleanup procedures on typical tropical urban environments. (authors)

Biosorption of Am-241 and Cs-137 by radioactive liquid waste by coffee husk

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Rafael Vicente de Padua; Sakata, Solange Kazumi; Bellini, Maria Helena; Marumo, Julio Takehiro, E-mail: jtmarumo@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2011-07-01

Radioactive Waste Management Laboratory of Nuclear and Energy Research Institute, IPEN-CNEN/SP, has stored many types of radioactive liquid wastes, including liquid scintillators, mixed wastes from chemical analysis and spent decontamination solutions. These wastes need special attention, because the available treatment processes are often expensive and difficult to manage. Biosorption using biomass of vegetable using agricultural waste has become a very attractive technique because it involves the removal of heavy metals ions by low cost biossorbents. The aim of this study is to evaluate the potential of the coffee husk to remove Am-241 and Cs-137 from radioactive liquid waste. The coffee husk was tested in two forms, treated and untreated. The chemical treatment of the coffee husk was performed with HNO{sub 3} and NaOH diluted solutions. The results showed that the coffee husk did not showed significant differences in behavior and capacity for biosorption for Am-241 and Cs-137 over time. Coffee husk showed low biosorption capacity for Cs-137, removing only 7.2 {+-} 1.0% in 4 hours of contact time. For Am-241, the maximum biosorption was 57,5 {+-} 0.6% in 1 hours. These results suggest that coffee husk in untreated form can be used in the treatment of radioactive waste liquid containing Am-241. (author)

Assessment of the Characteristic Aggregates during a Decontamination of Contaminated Concrete Waste

International Nuclear Information System (INIS)

Min, B. Y.; Choi, W. K.; Oh, W. Z.; Jung, C. H.; Park, J. W.

2008-01-01

During a decommissioning of nuclear plants and facilities, large quantities of slightly contaminated concrete wastes are generated. The exposure to radiation over many years could be hazardous to human health. In Korea, the decontamination and decommissioning of the retired TRIGA MARK II and III research reactors and a uranium conversion plant at the Korea Atomic Energy Research Institute (KAERI) has been under way. Hundreds of tons of concrete wastes are expected from the D and D of these facilities. Typically, the contaminated layer is only 1∼10mm thick because cementitious materials are porous media, the penetration of radionuclides may occur up to several centimeters from the surface of a material. Contaminated concrete waste can be of two forms, either a surface or bulk contamination. Bulk contamination usually arises from a neutron activation of nuclides during the service life on a component. Surface activity can be a loose contamination arising from a deposition of nuclides from an interfacing medium, and it also can be tightly bound. Most of the dismantled concrete wastes are slightly contaminated rather than activated. This decontamination can be accomplished during the course of a separation of the concrete wastes contaminated with radioactive materials through a thermal treatment step of the radionuclide (e.g. cesium and strontium), transportation of the radionuclide to fine aggregates through a mechanical treatment step such as a crushing, milling and sieving. Produced fine powder (paste) should be stabilized for the final disposal. Melting technology has been known as the one of the most effective technologies for a stabilization and volume reduction to the paste. Therefore, a melting may be a last step in the decontamination of a contaminated paste. The aim of this study was to establish the separation conditions for an optimum decontamination for the treatment of concrete wastes contaminated with radionuclides. The separation tests had been

Method of decontaminating radioactive-contaminated instruments

Energy Technology Data Exchange (ETDEWEB)

Urata, M; Fujii, M; Kitaguchi, H

1982-03-29

Purpose: To enable safety processing of liquid wastes by recovering radioactive metal ions remaining in the electrolytes after the decontamination procedure thereby decreasing the radioactivity. Method: In a decontamination tank containing electrolytes consisting of diluted hydrochloric acid and diluted sulfuric acid, are provided a radioactive contaminated instrument connected to an anode and a collector electrode made of stainless steel connected to a cathode respectively. Upon applying electrical current, the portion of the mother material to be decontaminated is polished electrolytically into metal ions and they are deposited as metal on the collection electrode. After completion of the decontamination, an ultrasonic wave generator is operated to strip and remove the oxide films. Thereafter, the anode is replaced with the carbon electrode and electrical current is supplied continuously, whereby the remaining metal ions are deposited and recovered as the metal on the collection electrode.

Decontamination and decommissioning technology tree and the current status of the technologies

Energy Technology Data Exchange (ETDEWEB)

Oh, Won Zin; Won, H.J.; Kim, G.N.; Lee, K.W.; Chol, W.K.; Jung, C.H.; Kim, C.J.; Kim, S.H.; Kwon, S.O.; Chung, C.M

2001-03-01

A technology tree diagram was developed on the basis of the necessary technologies applicable to the decontamination and decommissioning of nuclear facilities. The technology tree diagram is consist of 6 main areas such as characterization, decontamination, decommissioning and remote technology, radwaste management, site restoration, and decommissioning plan and engineering. Characterization is divided into 4 regions such as sampling and data collection, general characterization, chemical analysis and radiological analysis. Decontamination is also divided into 4 regions such as chemical decontamination, mechanical decontamination, the other decontamination technologies and new decontamination technologies. Decommissioning and remote technology area is divided into 4 regions such as cutting techniques, decommissioning technologies, new developing technologies and remote technologies. Radwaste management area is divided into 5 regions such as solid waste treatment, sludge treatment, liquid waste treatment, gas waste treatment and thermal treatment. Site restoration area is divided into 3 regions such as the evaluation of site contamination, soil decontamination and ground water decontamination. Finally, permission, decommissioning process, cost evaluation, quality assurance and the estimation of radionuclide inventory were mentioned in the decommissioning plan and engineering area. The estimated items for each technology are applicable domestic D and D facilities, D and D problem area and contamination/requirement, classification of D and D technology, similar technology, principle and overview of technology, status, science technology needs, implementation needs, reference and contact point.

Decontamination and decommissioning technology tree and the current status of the technologies

International Nuclear Information System (INIS)

Oh, Won Zin; Won, H. J.; Kim, G. N.; Lee, K. W.; Chol, W. K.; Jung, C. H.; Kim, C. J.; Kim, S. H.; Kwon, S. O.; Chung, C. M.

2001-03-01

A technology tree diagram was developed on the basis of the necessary technologies applicable to the decontamination and decommissioning of nuclear facilities. The technology tree diagram is consist of 6 main areas such as characterization, decontamination, decommissioning and remote technology, radwaste management, site restoration, and decommissioning plan and engineering. Characterization is divided into 4 regions such as sampling and data collection, general characterization, chemical analysis and radiological analysis. Decontamination is also divided into 4 regions such as chemical decontamination, mechanical decontamination, the other decontamination technologies and new decontamination technologies. Decommissioning and remote technology area is divided into 4 regions such as cutting techniques, decommissioning technologies, new developing technologies and remote technologies. Radwaste management area is divided into 5 regions such as solid waste treatment, sludge treatment, liquid waste treatment, gas waste treatment and thermal treatment. Site restoration area is divided into 3 regions such as the evaluation of site contamination, soil decontamination and ground water decontamination. Finally, permission, decommissioning process, cost evaluation, quality assurance and the estimation of radionuclide inventory were mentioned in the decommissioning plan and engineering area. The estimated items for each technology are applicable domestic D and D facilities, D and D problem area and contamination/requirement, classification of D and D technology, similar technology, principle and overview of technology, status, science technology needs, implementation needs, reference and contact point

Lawrence Livermore National Laboratory Decontamination and Waste Treatment Facility: Documentation of impact analysis for design alternatives presented in the Draft Environmental Impact Statement

International Nuclear Information System (INIS)

1988-05-01

Lawrence Livermore National Laboratory (LLNL) is proposing to construct and operate a new Decontamination and Waste Treatment Facility (DWTF). The proposed DWTF would replace the existing Hazardous Waste Management (HWM) facilities at LLNL. The US Department of Energy (DOE) is preparing a Draft Environmental Impact Statement (DEIS) to assess the environmental consequences of the proposed DWTF and its alternatives. This report presents the assumptions, methodologies, and analyses used to estimate the waste flows, air emissions, ambient air quality impacts, and public health risks that are presented in the DEIS. Two DWTF design alternatives (Level I and Level II) have been designated as reasonable design alternatives considering available technologies, environmental regulations, and current and future LLNL waste generation. Both design alternatives would include new, separate radioactive and nonradioactive liquid waste treatment systems, a solidification unit, a new decontamination facility, storage and treatment facilities for reactive materials, a radioactive waste storage area, receiving and classification areas, and a uranium burn pan. The Level I design alternative would include a controlled-air incinerator system, while the Level II design alternative would include a rotary kiln incinerator system. 43 refs., 4 figs., 24 tabs

Decontamination of radioactive contaminated protective wear using dry cleaning solvent

International Nuclear Information System (INIS)

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

2013-01-01

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

Separation of cobalt from synthetic intermediate and decontamination radioactive wastes using polyurethane foam

International Nuclear Information System (INIS)

Rao, S.V.S.; Lal, K.B.; Narasimhan, S.V.; Ahmed, J.

1997-01-01

Studies have been carried out on the removal of radioactive cobalt ( 60 Co) from synthetic intermediate level waste (ILW) and decontamination waste using neat polyurethane (PU) foam as well as n-tributyl phosphate-polyurethane (TBP-PU) foam. The radioactive cobalt has been extracted on the PU foam as cobalt thiocyanate from the ILW. Maximum removal of cobalt has been observed when the concentration of thiocyanate in the solution is about 0.4 M. Cobalt can be separated from decontamination waste containing ethylenediaminetetraacetic acid (EDTA) and iron(II). The extent of extraction of cobalt is slow and the separation of iron and cobalt is better with the neat PU foam compared to the TBP-PU foam. The presence of iron in the decontamination waste facilitates the extraction of cobalt thiocyanate on the PU foam. Column studies have been carried out in order to extend these studies to the plant scale. The capacities of the PU foams for cobalt have been determined. The effect of density and the surface area of PU foam have been investigated. Fourier Transform Infrared (FT-IR) spectral studies have been conducted to find out the interaction between PU foam and cobalt thiocyanate species

Design and implementation of an intensified coprecipitation reactor for the treatment of liquid radioactive wastes

International Nuclear Information System (INIS)

Flouret, Julie; Barre, Yves; Muhr, Herve; Plasari, Edouard

2013-01-01

The coprecipitation is a robust and inexpensive process for the treatment of important volumes of low and intermediate radioactive level liquid wastes. Its major inconvenient is the huge volume of sludge generated. The purpose of this work is to optimize the industrial coprecipitation continuous process by achieving the following objectives: - maximize the decontamination efficiency; - minimize the volume of sludge generated by the process; - reduce the treatment cost decreasing the installation volume. An innovative reactor with an infinite recycling ratio was therefore designed. It is a multifunctional reactor composed of two zones: a perfectly mixed precipitation zone and a classifier to perform liquid-solid separation. The experiments are focused on the coprecipitation of strontium by barium sulphate. The effluent containing sulphate ions and the barium nitrate solution are injected in the reaction zone where strontium and barium co-precipitate as sulphates. The produced solid phase is returned into the reaction zone by the classifier and goes out slowly from the reactor bottom with a residence time much higher than the liquid phase. This creates both a high concentration of solid phase in the reaction zone and a high efficiency of decontamination. The experimental conditions simulate the industrial effluents. The total treatment flow rate is 17 L/h, with an effluent flow rate of 16 L/h and a reactive flow rate of 1 L/h, hence a mean residence time of 10 minutes. In these experimental conditions, the molar ratio sulphate/barium after mixing corresponds to 4.9. These conditions are used in the reprocessing plant of La Hague. The decontamination factor reached in these experimental conditions is excellent: DF = 1500. The decontamination factor obtained with the classical continuous process is only equal to 60. Different process parameters are studied in order to optimize the reactor/classifier: residence time, barium nitrate flow rate and racking flow rate. The

Decontamination and decommissioning of the West Valley Reprocessing Plant

International Nuclear Information System (INIS)

Daugherty, H.F.; Keel, R.

1986-11-01

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

Recent advances in liquid membranes and their applications in nuclear waste processing: an overview

Energy Technology Data Exchange (ETDEWEB)

Shukla, J P; Iyer, R H [Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai (India)

1994-06-01

Membrane extraction, combining the processes of extraction, scrubbing and stripping in a single step, demonstrates the inherent capability of solvent extraction under non-equilibrium conditions. Permeant transport across various liquid membrane (LM) configurations, viz. bulk liquid, emulsion liquid and supported liquid membranes has great potential for applications in the nuclear field particularly in the decontamination of low and medium level radioactive wastes. Potential practical applications of such membranes have also been envisaged in the recovery of metals from hydrometallurgical leach solutions and in plutonium and americium removal from nitric acid waste streams generated by plutonium recovery operations in the PUREX process. Studies carried out have established that minor actinides like uranium, plutonium and americium from process effluents can easily be transported across polymeric and liquid type membranes through the use of specific ionophores dissolved in an appropriate liquid membrane phase. The possibility of the membrane extraction of fission palladium from acidic wastes has also been demonstrated by the use of some soft bases. An overview of these results and also some of the recent radiochemical applications of energy - efficient LM processes including directions for future research are outlined in this paper. (author). 19 refs., 1 fig., 2 tabs.

Electromagnetic mixed waste processing system for asbestos decontamination

Energy Technology Data Exchange (ETDEWEB)

Kasevich, R.S. [KAI Technologies, Inc., Portsmouth, NH (United States); Vaux, W.G. [Westinghouse Electric Corp., Pittsburgh, PA (United States); Nocito, T. [Ohio DSI Corp., New York (United States)

1995-10-01

DOE sites contain a broad spectrum of asbestos materials (cloth, pipe lagging, sprayed insulation and other substances) which are contaminated with a combination of hazardous and radioactive wastes due to its use during the development of the U.S. nuclear weapons complex. These wastes consist of cutting oils, lubricants, solvents, PCB`s, heavy metals and radioactive contaminants. The radioactive contaminants are the activation, decay and fission products of DOE operations. The asbestos must be converted by removing and separating the hazardous and radioactive materials to prevent the formation of mixed wastes and to allow for both sanitary disposal and effective decontamination. Currently, no technology exists that can meet these sanitary and other objectives.

Electromagnetic mixed waste processing system for asbestos decontamination

International Nuclear Information System (INIS)

Kasevich, R.S.; Vaux, W.G.; Nocito, T.

1995-01-01

DOE sites contain a broad spectrum of asbestos materials (cloth, pipe lagging, sprayed insulation and other substances) which are contaminated with a combination of hazardous and radioactive wastes due to its use during the development of the U.S. nuclear weapons complex. These wastes consist of cutting oils, lubricants, solvents, PCB's, heavy metals and radioactive contaminants. The radioactive contaminants are the activation, decay and fission products of DOE operations. The asbestos must be converted by removing and separating the hazardous and radioactive materials to prevent the formation of mixed wastes and to allow for both sanitary disposal and effective decontamination. Currently, no technology exists that can meet these sanitary and other objectives

Status of the ORNL liquid low-level waste management upgrades

International Nuclear Information System (INIS)

Robinson, S.M.; Kent, T.E.; DePaoli, S.M.

1995-08-01

The strategy for management of the Oak Ridge National Laboratory's (ORNL's) radioactively contaminated liquid waste was reviewed. The latest information on waste characterization, regulations, US Department of Energy (DOE) budget guidance, and research and development programs was evaluated to determine how the strategy should be revised. Few changes are needed to update the strategy to reflect new waste characterization, research, and regulatory information. However, recent budget guidance from DOE indicates that minimum funding will not be sufficient to accomplish original objectives to upgrade the liquid low-level waste (LLLW) system to be in compliance with the Federal Facilities Agreement compliance, provide long-term LLLW treatment capability, and minimize Environmental Safety ampersand Health risks. Options are presented that might allow the ORNL LLLW system to continue operations temporarily but significantly reduce its capabilities to handle emergency situations, provide treatment for new waste streams, and accommodate waste from the Environmental Restoration Program and from decontamination and decommissioning of surplus facilities. These options are also likely to increase worker radiation exposure, risk of environmental insult, and generation of solid waste for on-site and off-site disposal/storage beyond existing facility capacities. The strategy will be fully developed after receiving additional guidance. The proposed budget limitations are too severe to allow ORNL to meet regulatory requirements or continue operations long term

Method of decontaminating radioactive-contaminated instruments

International Nuclear Information System (INIS)

Urata, Megumu; Fujii, Masaaki; Kitaguchi, Hiroshi.

1982-01-01

Purpose: To enable safety processing of liquid wastes by recovering radioactive metal ions remaining in the electrolytes after the decontamination procedure thereby decreasing the radioactivity. Method: In a decontamination tank containing electrolytes consisting of diluted hydrochloric acid and diluted sulfuric acid, are provided a radioactive contaminated instrument connected to an anode and a collector electrode made of stainless steel connected to a cathode respectively. Upon applying electrical current, the portion of the mother material to be decontaminated is polished electrolytically into metal ions and they are deposited as metal on the collection electrode. After completion of the decontamination, an ultrasonic wave generator is operated to strip and remove the oxide films. Thereafter, the anode is replaced with the carbon electrode and electrical current is supplied continuously, whereby the remaining metal ions are deposited and recovered as the metal on the collection electrode. (Yoshino, Y.)

Biosorption of Am-241 and Cs-137 by radioactive liquid waste by coffee husk

International Nuclear Information System (INIS)

Ferreira, Rafael Vicente de Padua; Sakata, Solange Kazumi; Bellini, Maria Helena; Marumo, Julio Takehiro

2011-01-01

Radioactive Waste Management Laboratory of Nuclear and Energy Research Institute, IPEN-CNEN/SP, has stored many types of radioactive liquid wastes, including liquid scintillators, mixed wastes from chemical analysis and spent decontamination solutions. These wastes need special attention, because the available treatment processes are often expensive and difficult to manage. Biosorption using biomass of vegetable using agricultural waste has become a very attractive technique because it involves the removal of heavy metals ions by low cost biossorbents. The aim of this study is to evaluate the potential of the coffee husk to remove Am-241 and Cs-137 from radioactive liquid waste. The coffee husk was tested in two forms, treated and untreated. The chemical treatment of the coffee husk was performed with HNO 3 and NaOH diluted solutions. The results showed that the coffee husk did not showed significant differences in behavior and capacity for biosorption for Am-241 and Cs-137 over time. Coffee husk showed low biosorption capacity for Cs-137, removing only 7.2 ± 1.0% in 4 hours of contact time. For Am-241, the maximum biosorption was 57,5 ± 0.6% in 1 hours. These results suggest that coffee husk in untreated form can be used in the treatment of radioactive waste liquid containing Am-241. (author)

Waste cleaning using CO2-acid microemulsion

International Nuclear Information System (INIS)

Park, Kwangheon; Sung, Jinhyun; Koh, Moonsung; Ju, Minsu

2011-01-01

Frequently we need to decontaminate radioactive wastes for volume reduction purposes. Metallic contaminants in wastes can be removed by dissolution to acid; however, this process produces a large amount of liquid acid waste. To reduce this 2ndary liquid waste, we suggest CO 2 -acid emulsion in removing metallic contaminants. Micro- and macro-emulsion of acid in liquid/supercritical CO 2 were successfully made. The formation region of microemulsion (water or acid in CO 2 ) was measured, and stability of the microemulsion was analyzed with respect to surfactant types. We applied micro- and macro-emulsion containing acid to the decontamination of radioactive metallic parts contaminated on the surface. The cleaning methods of micro- and macro-emulsion seemed better compared to the conventional acid cleaning. Moreover, these methods produce very small amount of secondary wastes. (author)

Advances in technologies for the treatment of low and intermediate level radioactive liquid wastes

International Nuclear Information System (INIS)

1994-01-01

In recent years the authorized maximum limits for radioactive discharges into the environment have been reduced considerably, and this, together with the requirement to minimize the volume of waste for storage or disposal and to declassify some wastes from intermediate to low level or to non-radioactive wastes, has initiated studies of ways in which improvements can be made to existing decontamination processes and also to the development of new processes. This work has led to the use of more specific precipitants and to the establishment of ion exchange treatment and evaporation techniques. Additionally, the use of combinations of some existing processes or of an existing process with a new technique such as membrane filtration is becoming current practice. New biotechnological, solvent extraction and electrochemical methods are being examined and have been proven at laboratory scale to be useful for radioactive liquid waste treatment. In this report an attempt has been made to review the current research and development of mature and advanced technologies for the treatment of low and intermediate level radioactive liquid wastes, both aqueous and non-aqueous. Non-aqueous radioactive liquid wastes or organic liquid wastes typically consist of oils, reprocessing solvents, scintillation liquids and organic cleaning products. A brief state of the art of existing processes and their application is followed by the review of advances in technologies, covering chemical, physical and biological processes. 213 refs, 33 figs, 3 tabs

Surveillance and maintenance plan for the inactive liquid low-level waste tanks at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

1994-11-01

ORNL has a total of 54 inactive liquid low-level waste (ILLLW) tanks. In the past, these tanks were used to contain radioactive liquid wastes from various research programs, decontamination operations, and reactor operations. The tanks have since been removed from service for various reasons; the majority were retired because of their age, some due to integrity compromises, and others because they did not meet the current standards set by the Federal Facilities Agreement (FFA). Many of the tanks contain residual radioactive liquids and/or sludges. Plans are to remediate all tanks; however, until remediation of each tank, this Surveillance and Maintenance (S ampersand M) Plan will be used to monitor the safety and inventory containment of these tanks

Radioactive Waste Decontamination Using Selentec Mag*SepSM Particles

International Nuclear Information System (INIS)

Walker, D.D.

1998-01-01

A sorbent containing crystalline silicotitanate (CST) tested for cesium removal from simulated Savannah River Site (SRS) soluble high activity waste showed rapid kinetics (1 h contact time) and high distribution coefficients (Kd 4000 mL/g of CST). The sorbent was prepared by Selective Environmental Technologies, Inc., (Selentec) as a MAG*SEP particle containing CST obtained from the Molecular Sieve Department of UOP, LLC, Results of preliminary tests suggest potential applications of the Selentec MAG*SEP particles to radioactive waste decontamination at SRS

Method and device of decontaminating radioactive solid wastes

International Nuclear Information System (INIS)

Hasegawa, Hiroshi; Tamada, Masami.

1983-01-01

Purpose: To surely enable grinding for the inner surface of hollow radioactive solid wastes such as pipeways or valves, as well as enable to decontaminate these solid wastes to such a level as being capable of processing in the same manner for the ordinary wastes. Method: A grinding piece abutting resiliently against the inner surface of a hollow radioactive solid wastes to be contaminated is attached at the top end of a flexible shaft, and the inner surface of the radioactive solid wastes is ground while rotating and slightly reciprocating, as well as axially moving the flexible shaft. Consequently, since the grinding piece is always abutted against the inner surface of the radioactive solid wastes just following after the profile of the inner surface, and the flexible shaft is resiliently flexed corresponding to the profile of the inner surface of the radioactive solid wastes, even an inner surface of radioactive solid wastes with a complicated configuration can surely be ground entirely. This surely enables to remove radioactive claddings and contaminated layers deposited on the surface. (Yoshihara, H.)

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 and partial dismantling of the Eurochemic reprocessing plant. Lessons learnt with respect to health physics and waste management

International Nuclear Information System (INIS)

Osipenco, A.; Detilleux, E.; Ferrari, P.

1980-01-01

After nine years in use, the installations of the Eurochemic reprocessing plant were washed down and decontaminated to enable access to be gained to all the cells and some items of equipment, the reuse of which is not envisaged, and dismantled. The procedures followed to ensure the radiation protection of the workers and the means and results of individual dosimetry are described. Some suggestions, mainly covering the lay-out of the cells and the items of equipment, are made in order to reduce still more the doses incurred. The production and control of the liquid and solid waste resulting from the decontamination and dismantling illustrate the advantage of using very high pressure water jets on the one hand and a careful covering of the walls and floors on the other [fr

Liquid waste sampling device

International Nuclear Information System (INIS)

Kosuge, Tadashi

1998-01-01

A liquid pumping pressure regulator is disposed on the midway of a pressure control tube which connects the upper portion of a sampling pot and the upper portion of a liquid waste storage vessel. With such a constitution, when the pressure in the sampling pot is made negative, and liquid wastes are sucked to the liquid pumping tube passing through the sampling pot, the difference between the pressure on the entrance of the liquid pumping pressure regulator of the pressure regulating tube and the pressure at the bottom of the liquid waste storage vessel is made constant. An opening degree controlling meter is disposed to control the degree of opening of a pressure regulating valve for sending actuation pressurized air to the liquid pumping pressure regulator. Accordingly, even if the liquid level of liquid wastes in the liquid waste storage vessel is changed, the height for the suction of the liquid wastes in the liquid pumping tube can be kept constant. With such procedures, sampling can be conducted correctly, and the discharge of the liquid wastes to the outside can be prevented. (T.M.)

Radioactive wastes: the challenge of volumes reduction

International Nuclear Information System (INIS)

Lepetit, V.

2005-01-01

The reduction of radioactive waste volumes is a priority for the French atomic energy commission (CEA) and for the Areva group. This article gives a rapid overview of the equipments and processes used to separate the valorizable materials from the ultimate wastes: pulsed separation columns and evaporators for the liquid-liquid extraction, compactification of spent fuel hulls, remote handling systems, recoverable colloid for surface decontamination, decontaminating foam, hydrothermal oxidation of organic and aqueous effluents, cold crucible vitrification etc. (J.S.)

Sorption of radioscesium from liquid radioactive waste on clay and immobilization by baking the clay at elevated temperature

Energy Technology Data Exchange (ETDEWEB)

Rashid, F.; Ghaffar, A. [Pakistan Inst. of Nuclear Science and Technology, Islamabad (Pakistan)

2011-07-01

The cesium-137 is the most problematic radionuclide in the radioactive wastes. It belongs to the IA group of the periodic table, highly reactive towards water and has very high mobility. Due to beta and gamma radiation hazards of radiocesium its decontamination and disposal requires some special tools and techniques. In this study globules of clay material was used for the removal of cesium from low level liquid radioactive wastes and further processed for immobilization. The aim of this study was to assess the solidification and immobilization of secondary waste. The secondary waste, after sorption of cesium from the liquid radioactive waste generated at this institute, was found compatible to the cement matrix used for the cementation process. The procedure for immobilization of low level radioactive waste with cementation using vitreous clay material as an additive was developed. (orig.)

Sorption of radioscesium from liquid radioactive waste on clay and immobilization by baking the clay at elevated temperature

International Nuclear Information System (INIS)

Rashid, F.; Ghaffar, A.

2011-01-01

The cesium-137 is the most problematic radionuclide in the radioactive wastes. It belongs to the IA group of the periodic table, highly reactive towards water and has very high mobility. Due to beta and gamma radiation hazards of radiocesium its decontamination and disposal requires some special tools and techniques. In this study globules of clay material was used for the removal of cesium from low level liquid radioactive wastes and further processed for immobilization. The aim of this study was to assess the solidification and immobilization of secondary waste. The secondary waste, after sorption of cesium from the liquid radioactive waste generated at this institute, was found compatible to the cement matrix used for the cementation process. The procedure for immobilization of low level radioactive waste with cementation using vitreous clay material as an additive was developed. (orig.)

Developing technologies for conditioning the liquid organic radioactive wastes from Cernavoda NPP

International Nuclear Information System (INIS)

Deneanu, N.; Popescu, I. V.; Teoreanu, I.

2004-01-01

The Institute for Nuclear Research (INR)-Pitesti has developed technologies for conditioning liquid organic radioactive wastes (oils, miscellaneous solvent and liquid scintillation cocktail) for Cernavoda NPP. This paper describes the new and viable solidification technology to convert liquid organic radioactive wastes into a stable monolithic form, which minimizes the probability to release tritium in the environment during interim storage, transportation and final disposal. These are normally LLW containing only relatively small quantities of beta/gamma emitting radionuclides and variable amounts of tritium with activity below E+08Bq/l. The INR research staff in the radwaste area developed treatment/conditioning techniques and also designed and tested the containers for the final disposal, following the approach in the management of radwaste related to the nuclear fuel cycle. Thus, the INR focused this type of activity on treating and conditioning the wastes generated at Cernavoda Nuclear Power Plant consisting of lubricants from primary fuelling machines and turbine, the miscellaneous solvent from decontamination operation and the liquid scintillation cocktail used in radiochemical analysis. Laboratory studies on cementation of liquid organic radioactive wastes have been undertaken at INR Pitesti. One simple system, similar to a conventional cement solidification unit, can treat radioactive liquid wastes, which are the major components of low- and medium-level radioactive wastes generated by a Nuclear Power Plant. It was proved that the solidified waste could meet the Waste Acceptance Criteria of the disposal site, in this case Baita-Bihor National Repository, as follows: - The wastes are deposited in type A packages; - The maximum expected quantities of this waste stream that will be produced in the future are 50 drums per year. The maximum specific tritium activity per drum is 10 9 Bq/m 3 ; - Compressive strengths of the samples should be greater than 50 MPa

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)

Method of continuously regenerating decontaminating electrolytic solution

International Nuclear Information System (INIS)

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

1985-01-01

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

Development of the SREX process for the treatment of ICPP liquid wastes

International Nuclear Information System (INIS)

Wood, D.J.; Law, J.D.; Garn, T.G.; Tillotson, R.D.; Tullock, P.A.; Todd, T.A.

1997-10-01

The removal of 90 Sr from actual and simulated wastes at the Idaho Chemical Processing Plant (ICPP) at the Idaho National Engineering and Environmental Laboratory (INEEL) has been demonstrated with the SREX process. This solvent extraction process employs the extractant 4',4'(5') di-(t-butylcyclohexano)-18-crown-6 in 1-octanol or a mixture of tributyl phosphate and a hydrocarbon diluent called Isopar L reg-sign. Process flowsheets have been designed for testing in countercurrent experiments with centrifugal contractors. The flowsheets have been designed using batch contract solvent extraction methods. The extraction of Sr as well as other interfering ions has been studied. The effect of various parameters including nitric acid dependence, extractant concentration dependence, hydronium ion concentration, and interferent concentrations upon the extraction efficiency of the process has been evaluated. The radiolysis of the SREX solvent has also been investigated as a function of absorbed gamma radiation. The extraction efficiency of the solvent has been shown to be only slightly dependent upon absorbed dose in the range 0--1,000 kGy. The decontamination of actual sodium-bearing waste and dissolved calcine solutions has been accomplished in batch contact flowsheets. Decontamination factors as high as 10E3 have been obtained with sequential batch contacts. Flowsheets have been developed to accomplish decontamination of the liquid wastes with respect to 90 Sr as well as the removal of Pb and Hg. Pb may be partitioned from the Sr fraction in a separate stripping procedure using ammonium citrate. This work has led to the formulation of countercurrent flowsheets which have been tested in centrifugal contractors with actual waste and reported in the document INEEL/EXT-97-00832

222-S radioactive liquid waste line replacement and 219-S secondary containment upgrade, Hanford Site, Richland, Washington

International Nuclear Information System (INIS)

1995-01-01

The U.S. Department of Energy (DOE) is proposing to: (1) replace the 222-S Laboratory (222-S) radioactive liquid waste drain lines to the 219-S Waste Handling Facility (219-S); (2) upgrade 219-S by replacing or upgrading the waste storage tanks and providing secondary containment and seismic restraints to the concrete cells which house the tanks; and (3) replace the transfer lines from 219-S to the 241-SY Tank Farm. This environmental assessment (EA) has been prepared in compliance with the National Environmental Policy Act (NEPA) of 1969, as amended, the Council on Environmental Quality Regulations for Implementing the Procedural Provisions of NEPA (40 Code of Federal Regulations [CFR] 1500-1508), and the DOE Implementing Procedures for NEPA (10 CFR 1021). 222-S is used to perform analytical services on radioactive samples in support of the Tank Waste Remediation System and Hanford Site environmental restoration programs. Activities conducted at 222-S include decontamination of analytical processing and support equipment and disposal of nonarchived radioactive samples. These activities generate low-level liquid mixed waste. The liquid mixed waste is drained through pipelines in the 222-S service tunnels and underground concrete encasements, to two of three tanks in 219-S, where it is accumulated. 219-S is a treatment, storage, and/or disposal (TSD) unit, and is therefore required to meet Washington Administrative Code (WAC) 173-303, Dangerous Waste Regulations, and the associated requirements for secondary containment and leak detection. The service tunnels are periodically inspected by workers and decontaminated as necessary to maintain as low as reasonably achievable (ALARA) radiation levels. Although no contamination is reaching the environment from the service tunnels, the risk of worker exposure is present and could increase. 222-S is expected to remain in use for at least the next 30 years to serve the Hanford Site environmental cleanup mission

A Planning Tool for Estimating Waste Generated by a Radiological Incident and Subsequent Decontamination Efforts - 13569

International Nuclear Information System (INIS)

Boe, Timothy; Lemieux, Paul; Schultheisz, Daniel; Peake, Tom; Hayes, Colin

2013-01-01

Management of debris and waste from a wide-area radiological incident would probably constitute a significant percentage of the total remediation cost and effort. The U.S. Environmental Protection Agency's (EPA's) Waste Estimation Support Tool (WEST) is a unique planning tool for estimating the potential volume and radioactivity levels of waste generated by a radiological incident and subsequent decontamination efforts. The WEST was developed to support planners and decision makers by generating a first-order estimate of the quantity and characteristics of waste resulting from a radiological incident. The tool then allows the user to evaluate the impact of various decontamination/demolition strategies on the waste types and volumes generated. WEST consists of a suite of standalone applications and Esri R ArcGIS R scripts for rapidly estimating waste inventories and levels of radioactivity generated from a radiological contamination incident as a function of user-defined decontamination and demolition approaches. WEST accepts Geographic Information System (GIS) shape-files defining contaminated areas and extent of contamination. Building stock information, including square footage, building counts, and building composition estimates are then generated using the Federal Emergency Management Agency's (FEMA's) Hazus R -MH software. WEST then identifies outdoor surfaces based on the application of pattern recognition to overhead aerial imagery. The results from the GIS calculations are then fed into a Microsoft Excel R 2007 spreadsheet with a custom graphical user interface where the user can examine the impact of various decontamination/demolition scenarios on the quantity, characteristics, and residual radioactivity of the resulting waste streams. (authors)

Solidification of low-level radioactive liquid waste using a cement-silicate process

International Nuclear Information System (INIS)

Grandlund, R.W.; Hayes, J.F.

1979-01-01

Extensive use has been made of silicate and Portland cement for the solidification of industrial waste and recently this method has been successfully used to solidify a variety of low level radioactive wastes. The types of wastes processed to date include fuel fabrication sludges, power reactor waste, decontamination solution, and university laboratory waste. The cement-silicate process produces a stable solid with a minimal increase in volume and the chemicals are relatively inexpensive and readily available. The method is adaptable to either batch or continuous processing and the equipment is simple. The solid has leaching characteristics similar to or better than plain Portland cement mixtures and the leaching can be further reduced by the use of ion-exchange additives. The cement-silicate process has been used to solidify waste containing high levels of boric acid, oils, and organic solvents. The experience of handling the various types of liquid waste with a cement-silicate system is described

Conversion of transuranic waste to low level waste by decontamination: a technical and economic evaluation

International Nuclear Information System (INIS)

Allen, R.P.; Hazelton, R.F.

1984-12-01

A study was conducted to evaluate the technical and economic feasibility of using in-situ decontamination techniques to convert glove boxes and other large TRU-contaminated components directly into LLW. The results of the technical evaluation indicate that in-situ decontamination of these types of components to non-TRU levels is technically feasible. Applicable decontamination techniques include electropolishing, hand scrubbing, chemical washes/sprays, strippable coatings and Freon spray-cleaning. The removal of contamination from crevices and other holdup areas remains a problem, but may be solved through further advances in decontamination technology. Also, the increase in the allowable maximum TRU level from 10 nCi/g to 100 nCi/g as defined in DOE Order 5820.2 reduces the removal requirement and facilitates measurement of the remaining quantities. The major emphasis of the study was on a cost/benefit evaluation that included a review and update of previous analyses and evaluations of TRU-waste volume reduction and conversion options. The results of the economic evaluation show, for the assumptions used, that there is a definite cost incentive to size reduce large components, and that decontamination of sectioned material has become cost competitive with the size reduction options. In-situ decontamination appears to be the lowest cost option when based on routine-type operations conducted by well-trained and properly equipped personnel. 16 references, 1 figure, 7 tables

Radioactive liquid waste filtering device

International Nuclear Information System (INIS)

Inami, Ichiro; Tabata, Masayuki; Kubo, Koji.

1988-01-01

Purpose: To prevent clogging in filter materials and improve the filtration performance for radioactive liquid wastes without increasing the amount of radioactive wastes. Constitution: In a radioactive waste filtering device, a liquid waste recycling pipe and a liquid recycling pump are disposed for recycling the radioactive liquid wastes in a liquid wastes vessel. In this case, the recycling pipe and the recycling pump are properly selected so as to satisfy the conditions capable of making the radioactive liquid wastes flowing through the pipe to have the Reynolds number of 10 4 - 10 5 . By repeating the transportation of radioactive liquid wastes in the liquid waste vessel through the liquid waste recycling pipe by the liquid waste recycling pump and then returning them to the liquid waste vessel again, particles of fine grain size in the suspended liquids are coagulated with each other upon collision to increase the grain size of the suspended particles. In this way, clogging of the filter materials caused by the particles of fine grain size can be prevented, thereby enabling to prevent the increase in the rising rate of the filtration differential pressure, reduce the frequency for the occurrence of radioactive wastes such as filter sludges and improve the processing performance. (Kamimura, M.)

Low-level liquid waste decontamination by organic ion exchange

International Nuclear Information System (INIS)

Lee, D.D.; Campbell, D.O.; Dillow, T.A.

1990-01-01

Improved processes are being developed to treat contaminated liquid wastes that have been and continue to be generated at Oak Ridge National Laboratory. Promising results have been obtained for cesium removal with a new resorcinol-based organic resin developed at the Savannah River Site. In tests of cesium removal, it was superior to other available resins, such as Duolite CS-100, with the distribution coefficient being limited primarily by competition from potassium and nearly independent of the sodium concentration. The optimum pH was approximately 12.5 in high NaNO 3 concentrations (>2 M). A fairly low flow velocity was required to yield sharp breakthrough of the loaded cesium. The resin was much less effective for strontium removal, which was limited by competition from sodium. If both cesium and strontium must be removed, another resin column or a mixed bed with a chelating resin should be used

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

Science.gov (United States)

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

2009-01-30

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

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)

Evaporation of low-activity-level liquid waste at Tokai Reprocessing Plant, 1

International Nuclear Information System (INIS)

Nojima, Yasuo; Nemoto, Yuichi; Fukushima, Misao; Shibuya, Jun; Miyahara, Kenji

1983-01-01

The operation of Tokai reprocessing plant started in 1977. The determination of the decontamination factors (DF) of the evaporators for low activity level liquid waste (LALW) has been made through the operation. This paper deals with the examination of the first evaporator located at the LALW treatment plant. The operational principle and condition of the evaporator system are briefly explained. The effects of wire-mesh demisters and liquid properties on the decontamination factor were examined in this study. The results are summarized as follows: (1) The DF decreased with the increasing vapor mass velocity on account of entrainment. (2) The DF was able to be improved by using wire-mesh demisters when the vapor mass velocity was less than 2,500 kg/m 2 h. Practically, the most suitable vapor velocity for the evaporator was around 2,000 kg/m 2 h. (3) The DF in the evaporator for 137 Cs, 144 Ce, 90 Sr and 106 Ru was between 10 3 and 10 4 . Regarding 106 Ru, the DF in acid evaporation was less than that in alkaline evaporation. (Aoki, K.)

Treatment of liquid waste containing alpha nuclides by adsorption

International Nuclear Information System (INIS)

Zeng Jishu; Su Xiguang; Xia Dejing; Fan Sianhua

1997-01-01

In this paper, experimental investigations on the removal of actinides from a decontaminating waste stream by using adsorption technique following the cementation of a resultant absorbent sludge are described. One kind of apatites was selected as an actinide absorbent from a number of indigenous materials by batch equilibrium tests. The influence of contact time, temperature, particle size and pH variables on the adsorption of actinides is given. The removal of total alpha activity is higher tan 97% by absorbent precipitation process when the absorbent addition percentage of the liquid waste is more than 3.25 wt%, making alpha-activity level of the primary waste stream below 3.7 x 10 3 Bq/L, which can meet the acceptance requirements of the Low Level Radwaste Treatment Plant. The studies on the cementation of the absorbent sludge included the selection of cements used for solidification, formulation and characterization of the selected cemented waste forms. The results obtained have shown that both 525 type Portland cement and 325 type Portland pozzolana cement were compatible with the absorbent sludge. The selected cemented waste forms meet the requirements of the Chinese National Standard (GB 14569.1-93): Characteristic Requirements for Solidified Waste of Low and Intermediate Level Radioactive Waste - Cement Solidified Waste. (author). 9 refs, 3 figs, 14 tabs

Design of Biochemical Oxidation Process Engineering Unit for Treatment of Organic Radioactive Liquid Waste

International Nuclear Information System (INIS)

Zainus Salimin; Endang Nuraeni; Mirawaty; Tarigan, Cerdas

2010-01-01

Organic radioactive liquid waste from nuclear industry consist of detergent waste from nuclear laundry, 30% TBP-kerosene solvent waste from purification or recovery of uranium from process failure of nuclear fuel fabrication, and solvent waste containing D 2 EHPA, TOPO, and kerosene from purification of phosphoric acid. The waste is dangerous and toxic matter having low pH, high COD and BOD, and also low radioactivity. Biochemical oxidation process is the effective method for detoxification of organic waste and decontamination of radionuclide by bio sorption. The result process are sludges and non radioactive supernatant. The existing treatment facilities radioactive waste in Serpong can not use for treatment of that’s organics waste. Dio chemical oxidation process engineering unit for continuous treatment of organic radioactive liquid waste on the capacity of 1.6 L/h has been designed and constructed the equipment of process unit consist of storage tank of 100 L capacity for nutrition solution, 2 storage tanks of 100 L capacity per each for liquid waste, reactor oxidation of 120 L, settling tank of 50 L capacity storage tank of 55 L capacity for sludge, storage tank of 50 capacity for supernatant. Solution on the reactor R-01 are added by bacteria, nutrition and aeration using two difference aerators until biochemical oxidation occurs. The sludge from reactor of R-01 are recirculated to the settling tank of R-02 and on the its reverse operation biological sludge will be settled, and supernatant will be overflow. (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

Waste and decontamination services FY 94 Multi-Year Program Plan Phase II WBS No. 1.2.3

International Nuclear Information System (INIS)

Cruz, E.A.

1994-05-01

During the remediation of the Hanford Site large volumes of radioactive and mixed solid waste are expected to be produced, thus creating the need for subsequent decontamination, treatment, storage, and/or waste disposal. The program mission is to manage current and future contaminated solid waste streams in a safe, responsible, cost effective and legally compliant manner. This document presents the strategy and technical requirements, along with key objectives and deliverables for the waste and decontamination services program for fiscal year 1994. Time schedules, cost estimates, and justification for each proposed activity are given in tables and charts

Attapulgite, a decontaminating medium, research tool in the radioprotection field

International Nuclear Information System (INIS)

Panciatici, G.; Belfiore, A.; Poggianti, M.

1993-01-01

Gels based on attapulgite, obtained by mixing attapulgite, a clay, with water or chemicals have been used as decontaminating agents. The method has been optimized through extensive scale laboratory experiments carried out under standard conditions. A wide variety of materials, used in nuclear technologies, and significant radionuclides have been tested. Gels obtained with water only in some cases allow full decontamination, when acids are added to clay, complete contamination removal, is possible except for extreme pHs radionuclides solution and on non-passivated or porous surfaces. The optimized decontaminating technique has successively been set up and applied on materials contaminated by routine or accident. Laboratory scale results have been confirmed through practical use. Process data are reported. This method is simple to perform and requires no special equipment. No liquid radioactive waste arises from the process and the resulting solid waste can be conditioned with cement

Determination of Na+ and K+ ions in the high-level liquid waste by ion chromatography (IC)

International Nuclear Information System (INIS)

Chen Lianzhong; Ma Guilan

1992-01-01

The determination of Na + and k + ions in the high-level liquid waste is investigated using ion chromatography. In order to protect the low capacity ion exchange resin in single column IC and remove the transition metal as well as other heavy metal ions that are contained in liquid waste, the pretreatment column with EDTA chelating resin is used. Those impurity metal ions are strongly absorbed by EDTA chelating resin and 100% of Na + and K + ions in the solution are eluted. The ability of the decontamination of EDTA chelating resin is satisfactory. The sample of the high-level liquid waste is diluted appropriately, then an aliquot of the sample is passed through the pretreatment column with EDTA chelating resin, the eluate is analysed by single column ion chromatography. The precision of this method is better than 5% for the determination of Na + and K + ions (at μg· ml -1 level)

A Planning Tool for Estimating Waste Generated by a Radiological Incident and Subsequent Decontamination Efforts - 13569

Energy Technology Data Exchange (ETDEWEB)

Boe, Timothy [Oak Ridge Institute for Science and Education, Research Triangle Park, NC 27711 (United States); Lemieux, Paul [U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States); Schultheisz, Daniel; Peake, Tom [U.S. Environmental Protection Agency, Washington, DC 20460 (United States); Hayes, Colin [Eastern Research Group, Inc, Morrisville, NC 26560 (United States)

2013-07-01

Management of debris and waste from a wide-area radiological incident would probably constitute a significant percentage of the total remediation cost and effort. The U.S. Environmental Protection Agency's (EPA's) Waste Estimation Support Tool (WEST) is a unique planning tool for estimating the potential volume and radioactivity levels of waste generated by a radiological incident and subsequent decontamination efforts. The WEST was developed to support planners and decision makers by generating a first-order estimate of the quantity and characteristics of waste resulting from a radiological incident. The tool then allows the user to evaluate the impact of various decontamination/demolition strategies on the waste types and volumes generated. WEST consists of a suite of standalone applications and Esri{sup R} ArcGIS{sup R} scripts for rapidly estimating waste inventories and levels of radioactivity generated from a radiological contamination incident as a function of user-defined decontamination and demolition approaches. WEST accepts Geographic Information System (GIS) shape-files defining contaminated areas and extent of contamination. Building stock information, including square footage, building counts, and building composition estimates are then generated using the Federal Emergency Management Agency's (FEMA's) Hazus{sup R}-MH software. WEST then identifies outdoor surfaces based on the application of pattern recognition to overhead aerial imagery. The results from the GIS calculations are then fed into a Microsoft Excel{sup R} 2007 spreadsheet with a custom graphical user interface where the user can examine the impact of various decontamination/demolition scenarios on the quantity, characteristics, and residual radioactivity of the resulting waste streams. (authors)

LCA of strippable coatings and of steam vacuum technology used for nuclear plants decontamination

International Nuclear Information System (INIS)

Guidi, Giambattista; Cumo, Fabrizio; Santoli, Livio de

2010-01-01

The application of strippable coatings is an innovative technology for decontamination of nuclear plants and for any decontamination project aiming at removing surface contamination. An adhesive plastic coating is applied on the contaminated surface. The strippable coating is allowed to cure for up to 24 h, after which it can be easily peeled. The coating traps the contaminants in the polymer matrix. Strippable coatings are non-toxic and do not contain volatile compounds or heavy metals. Since the coating constitutes a solid waste, disposal is easier than treating contaminated liquid wastes, produced by the baseline technology: steam vacuum cleaning, based upon superheated pressurized water in order to remove contaminants from floors and walls. A life cycle assessment (LCA) has been carried out with the purpose of comparing the strippable coating with the steam vacuum technology. The functional unit of the study is represented by a surface of 1 m 2 to be decontaminated. The results of LCA achieved using Sima Pro 5.0 registered software confirm the good environmental performances of strippable coatings. Taking into account both LCA and environmental costs for liquid wastes, the advantages of strippable coatings will be more and more evident. (orig.)

The study of sorption of cesium radionuclides by 'T-55' ferrocyanide sorbent from various types of liquid radioactive wastes

International Nuclear Information System (INIS)

Semenischev, V.S.; Voronina, A.V.; Bykov, A.A.

2013-01-01

The sorption of caesium by T-55 sorbent from different types of liquid radioactive wastes is studied. It is shown that the sorbent can be used for extraction of cesium from high level acidic and saline solutions and also for decontamination of caesium contaminated waters containing surfactants and EDTA. (author)

Laboratory Scoping Tests Of Decontamination Of Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

Energy Technology Data Exchange (ETDEWEB)

Taylor-Pashow, Kathryn M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nash, Charles A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, Charles L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, Daniel J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Wilmarth, William R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2014-01-21

compatible with longterm tank storage and immobilization methods. For this new application, testing is needed to demonstrate acceptable treatment sorbents and precipitating agents and measure decontamination factors for additional radionuclides in this unique waste stream. The origin of this LAW Off-Gas Condensate stream will be the liquids from the Submerged Bed Scrubber (SBS) and the Wet Electrostatic Precipitator (WESP) from the LAW melter off-gas system. The stream is expected to be a dilute salt solution with near neutral pH, and will likely contain some insoluble solids from melter carryover. The soluble components are expected to be mostly sodium and ammonium salts of nitrate, chloride, and fluoride. This stream has not been generated yet and will not be available until the WTP begins operation, but a simulant has been produced based on models, calculations, and comparison with pilot-scale tests. One of the radionuclides that is volatile and expected to be in high concentration in this LAW Off-Gas Condensate stream is Technetium-99 (⁹⁹Tc). Technetium will not be removed from the aqueous waste in the Hanford WTP, and will primarily end up immobilized in the LAW glass by repeated recycle of the off-gas condensate into the LAW melter. Other radionuclides that are also expected to be in appreciable concentration in the LAW Off-Gas Condensate are ¹²⁹I, ⁹⁰Sr, ¹³⁷Cs, and {sup 241}Am. This report discusses results of preliminary radionuclide decontamination testing of the simulant. Testing examined use of Monosodium Titanate (MST) to remove ⁹⁰Sr and actinides, inorganic reducing agents for ⁹⁹Tc, and zeolites for ¹³⁷Cs. Test results indicate that excellent removal of ⁹⁹Tc was achieved using Sn(II)Cl₂ as a reductant, coupled with sorption onto hydroxyapatite, even in the presence of air and at room temperature. This process was very effective at neutral pH, with a Decontamination

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

Decontamination and inspection plan for Phase 3 closure of the 300 area waste acid treatment system

International Nuclear Information System (INIS)

LUKE, S.N.

1999-01-01

This decontamination and inspection plan (DIP) describes decontamination and verification activities in support of Phase 3 closure of the 300 Area Waste Acid Treatment System (WATS). Phase 3 is the third phase of three WATS closure phases. Phase 3 attains clean closure conditions for WATS portions of the 334 and 311 Tank Farms (TF) and the 333 and 303-F Buildings. This DIP also describes designation and management of waste and debris generated during Phase 3 closure activities. Information regarding Phase 1 and Phase 2 for decontamination and verification activities closure can be found in WHC-SD-ENV-AP-001 and HNF-1784, respectively. This DIP is provided as a supplement to the closure plan (DOE/RL-90-11). This DIP provides the documentation for Ecology concurrence with Phase 3 closure methods and activities. This DIP is intended to provide greater detail than is contained in the closure plan to satisfy Ecology Dangerous Waste Regulations, Washington Administrative Code (WAC) 173-303-610 requirement that closure documents describe the methods for removing, transporting, storing, and disposing of all dangerous waste at the unit. The decontamination and verification activities described in this DIP are based on the closure plan and on agreements reached between Ecology and the U.S. Department of Energy, Richland Operations Office (DOE-RL) during Phase 3 closure activity workshops and/or project manager meetings (PMMs)

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)

SPEEDUP simulation of liquid waste batch processing. Revision 1

International Nuclear Information System (INIS)

Shannahan, K.L.; Aull, J.E.; Dimenna, R.A.

1994-01-01

The Savannah River Site (SRS) has accumulated radioactive hazardous waste for over 40 years during the time SRS made nuclear materials for the United States Department of Energy (DOE) and its predecessors. This waste is being stored as caustic slurry in a large number of 1 million gallon steel tanks, some of which were initially constructed in the early 1950's. SRS and DOE intend to clean up the Site and convert this waste into stable forms which then can be safely stored. The liquid waste will be separated into a partially decontaminated low-level and radioactive high-level waste in one feed preparation operation, In-Tank Precipitation. The low-level waste will be used to make a concrete product called saltstone in the Saltstone Facility, a part of the Defense Waste Processing Facility (DWPF). The concrete will be poured into large vaults, where it will be permanently stored. The high-level waste will be added to glass-formers and waste slurry solids from another feed preparation operation, Extended Sludge Processing. The mixture will then be converted to a stable borosilicate glass by a vitrification process that is the other major part of the DWPF. This glass will be poured into stainless steel canisters and sent to a temporary storage facility prior to delivery to a permanent underground storage site

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.)

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.)

Programs of recovery of radioactive wastes from the trenches and land decontamination of the radioactive waste storage center

International Nuclear Information System (INIS)

Jimenez D, J.; Reyes L, J.

1999-06-01

In this report there are the decontamination program of the land of the Radioactive Waste Storage Center, the Program of Recovery of the radioactive waste of the trenches, the recovery of polluted bar with cobalt 60, the recovery of minerals and tailings of uranium and of earth with minerals and tailings of uranium, the recovery of worn out sealed sources and the waste recovery with the accustomed corresponding actions are presented. (Author)

Lessons learned at West Valley during facility decontamination for re-use (1982--1988)

International Nuclear Information System (INIS)

Tundo, D.; Gessner, R.F.; Lawrence, R.E.

1988-11-01

The primary mission of the West Valley Demonstration Project (WVDP) is to solidify a large volume of high-level liquid waste (2.3 million liters -- 600,000 gallons) produced during reprocessing plant operations and stored in underground tanks. This is to be accomplished through the maximum use of existing facilities. This required a significant effort to remove existing equipment and to decontaminate areas for installation of liquid and cement processing systems in a safe environment while maintaining exposure to workers as low as reasonably achievable. The reprocessing plant occupied a building of about 33,000 m 2 (350,000 ft 2 ). When the WVDP was initiated, approximately 6 percent of the plant area was in a non-contaminated condition where personnel could function without protective clothing or radiological controls. From 1982 to 1988, an additional 64 percent of the plant was cleaned up and much of this converted to low- and high-level waste processing areas. The high-level liquid and resulting low-level liquids are now being treated in these areas using an Integrated Radwaste Treatment System (IRTS). The Project has now focused attention on installation, qualification and operation of a vitrification system which will convert the remaining high-level waste into borosilicate glass logs. The stabilized waste will be sent to a Federal Repository for long-term storage. From 1982 to 1988, about 70 technical reports were dealing with specific tasks and cleanup efforts. This report provides an overview of the decontamination and decommissioning work done in that period. The report emphasizes lessons learned during that effort. Significant advances were made in: remote and contact decontamination technology; personnel protection and training; planning and procedures; and radiological controls. 62 refs., 35 figs., 5 tabs

Cleanout and decontamination of radiochemical hot cells

International Nuclear Information System (INIS)

Surma, J.E.; Holton, L.K. Jr.; Katayama, Y.B.; Gose, J.E.; Haun, F.E.; Dierks, R.D.

1990-01-01

The Pacific Northwest Laboratory is developing and employing advanced remote and contact technologies in cleaning out and decontaminating six radiochemical hot cells at Hanford under the Department of Energy's Surplus Facilities Management Program. The program is using a series of remote and contact decontamination techniques to reduce costs and to significantly lower radiation doses to workers. Refurbishment of the cover blocks above the air lock trench reduced radiation exposure in the air lock and cleanout and decontamination of an analytical cell achieved a reduction in radioactive contamination. Nuclear Regulatory Commission-approved Type B burial boxes are also being used to reduce waste disposal costs and radiation doses. PNL is currently decommissioning its pilot-scale radioactive liquid-fed ceramic melter. Special tools have been developed and are being used to accomplish the world's first such effort. 4 refs., 5 figs

Preparation of SiO2-KCoFC composite ion-exchanger for removal of Cs in the soil decontamination waste solution

International Nuclear Information System (INIS)

Lee, Jung Joon; Moon, Jei kwon; Lee, Kune Woo

2009-01-01

The soil decontamination process has been developed for remediate the soil wastes excavated from the TRIGA research reactor sites. Even though the process was proven to be very effective for decontaminate the radioactive nuclides such as cesium and cobalt, the secondary spent solution should be treated with an appropriate method to minimize the waste volume. There are mainly two components in the spent decontamination solution of Cs and Co. The Co in the waste solution can be removed easily by precipitation under a basic condition. However, since the Cs is hardly removed by precipitation, an appropriate selective removal method should be employed. In this study, an inorganic composite ion exchanger of SiO 2 -KCoFC was prepared by sol-gel method for a removal of Cs in the decontamination waste solution. An optimum condition for a preparation of the composite ion exchanger and the adsorption performances of the prepared composite ion exchangers were evaluated

Decontamination of material in the Marcoule plutonium producing centre (1961)

International Nuclear Information System (INIS)

Rodier, J.; Bouzigues, H.; Boutot, P.

1961-01-01

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) [fr

Chemical treatment of radioactive liquid wastes from medical applications

International Nuclear Information System (INIS)

Castillo A, J.

1995-01-01

This work is a study about the treatment of the most important radioactive liquid wastes from medical usages, generated in medical institutions with nuclear medicine services. The radionuclides take in account are 32 P, 35 S, 125 I. The treatments developed and improved were specific chemical precipitations for each one of the radionuclides. This work involve to precipitate the radionuclide from the liquid waste, making a chemical compound insoluble in the aqueous phase, for this process the radionuclide stay in the precipitate, lifting the aqueous phase with a very low activity than the begin. The 32 P precipitated in form of Ca 3 32 P O 4 and Ca 2 H 32 P O 4 with a value for Decontamination Factor (DF) at the end of the treatment of 32. The 35 S was precipitated in form of Ba 35 SO 4 with a DF of 26. The 125 I was precipitated in Cu 125 I to obtain a DF of 24. The results of the treatments are between the limits given for the International Atomic Energy Agency and the 10 Code of Federal Regulation 20, for the safety release at the environment. (Author)

Decontamination of irradiated-fuel processing waste using manganese dioxide hydrate; Decontamination des effluents de traitement des combustibles irradies par le bioxyde de manganese hydrate

Energy Technology Data Exchange (ETDEWEB)

Auchapt, J M; Gaudier, J F [Commissariat a l' Energie Atomique, Chusclan (France). Centre de Production de Plutonium de Marcoule

1969-07-01

The 'manganese dioxide' process is designed to replace the 'calcium carbonate' treatment for low and medium activity wastes. The objective to attain during the research for a new process was the diminution of the volume of the sludge without decreasing the decontamination factor of the wastes. The new process involves addition in series of twice over 100 ppm of Mn{sup 2+} in the waste which has previously been made basic and oxidizing; the precipitate formed in situ is separated after each addition. The process has the advantage of increasing the decontamination of strontium. The treatment can be used in a plant including two decantation units and has given effective results when applied in such a plant. (author) [French] Le procede au ''bioxyde de manganese'' est destine a remplacer le traitement ''carbonate de calcium'' dans les effluents de moyenne activite. L'objectif poursuivi lors de la recherche d'un procede nouveau etait de diminuer le volume des boues sans diminuer le facteur de decontamination des effluents. Le nouveau traitement consiste a effectuer en cascade sur les effluents rendus basiques et oxydants une double precipitation de 100 ppm de Mn{sup 2+} avec separation intermediaire du precipite. Il presente en outre l'avantage d'ameliorer la decontamination en strontium. Le traitement est utilisable dans la chaine des deux decanteurs et a donne satisfaction lors de son exploitation industrielle. Le volume des boues seches a ete reduit d'un facteur 3 a 4 par rapport au traitement carbonate. (auteur)

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

International Nuclear Information System (INIS)

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

2009-01-01

A decontamination system for chemical warfare agents was developed and tested that combines a liquid decontamination reagent solution with solid sorbent particles. The components have fewer safety and environmental concerns than traditional chlorine bleach-based products or highly caustic solutions. The liquid solution, based on Decon Green TM , has hydrogen peroxide and a carbonate buffer as active ingredients. The best solid sorbents were found to be a copolymer of ethylene glycol dimethacrylate and n-lauryl methacrylate (Polytrap 6603 Adsorber); or an allyl methacrylate cross-linked polymer (Poly-Pore E200 Adsorber). These solids are human and environmentally friendly and are commonly used in cosmetics. The decontaminant system was tested for reactivity with pinacolyl methylphosphonofluoridate (Soman, GD), bis(2-chloroethyl)sulfide (Mustard, HD), and S-(2-diisopropylaminoethyl) O-ethyl methylphosphonothioate (VX) by using NMR Spectroscopy. Molybdate ion (MoO 4 -2 ) was added to the decontaminant to catalyze the oxidation of HD. The molybdate ion provided a color change from pink to white when the oxidizing capacity of the system was exhausted. The decontaminant was effective for ratios of agent to decontaminant of up to 1:50 for VX (t 1/2 ≤ 4 min), 1:10 for HD (t 1/2 1/2 < 2 min). The vapor concentrations of GD above the dry sorbent and the sorbent with decontamination solution were measured to show that the sorbent decreased the vapor concentration of GD. The E200 sorbent had the additional advantage of absorbing aqueous decontamination solution without the addition of an organic co-solvent such as isopropanol, but the rate depended strongly on mixing for HD

Treatment of liquid waste containing alpha nuclides by adsorption

Energy Technology Data Exchange (ETDEWEB)

Jishu, Zeng; Xiguang, Su; Dejing, Xia; Sianhua, Fan [China Inst. of Atomic Energy, Beijing (China). Radiochemistry Dept.

1997-02-01

In this paper, experimental investigations on the removal of actinides from a decontaminating waste stream by using adsorption technique following the cementation of a resultant absorbent sludge are described. One kind of apatites was selected as an actinide absorbent from a number of indigenous materials by batch equilibrium tests. The influence of contact time, temperature, particle size and pH variables on the adsorption of actinides is given. The removal of total alpha activity is higher tan 97% by absorbent precipitation process when the absorbent addition percentage of the liquid waste is more than 3.25 wt%, making alpha-activity level of the primary waste stream below 3.7 x 10{sup 3} Bq/L, which can meet the acceptance requirements of the Low Level Radwaste Treatment Plant. The studies on the cementation of the absorbent sludge included the selection of cements used for solidification, formulation and characterization of the selected cemented waste forms. The results obtained have shown that both 525 type Portland cement and 325 type Portland pozzolana cement were compatible with the absorbent sludge. The selected cemented waste forms meet the requirements of the Chinese National Standard (GB 14569.1-93): Characteristic Requirements for Solidified Waste of Low and Intermediate Level Radioactive Waste - Cement Solidified Waste. (author). 9 refs, 3 figs, 14 tabs.

Treatment of low-level radioactive waste liquid by reverse osmosis

International Nuclear Information System (INIS)

Buckley, L.P.; Sen Gupta, S.K.; Slade, J.A.

1995-01-01

The processing of low-level radioactive waste (LLRW) liquids that result from operation of nuclear power plants with reverse osmosis systems is not common practice. A demonstration facility is operating at Chalk River Laboratories (of Atomic Energy of Canada Limited), processing much of the LLRW liquids generated at the site from a multitude of radioactive facilities, ranging from isotope production through decontamination operations and including chemical laboratory drains. The reverse osmosis system comprises two treatment steps--spiral wound reverse osmosis followed by tubular reverse osmosis--to achieve an average volume reduction factor of 30:1 and a removal efficiency in excess of 99% for most radioactive and chemical species. The separation allows the clean effluent to be discharged without further treatment. The concentrated waste stream of 3 wt% total solids is further processed to generate a solid product. The typical lifetimes of the membranes have been nearly 4000 hours, and replacement was required based on increased pressure drops and irreversible loss of permeate flux. Four years of operating experience with the reverse osmosis system, to demonstrate its practicality and to observe and record its efficiency, maintenance requirements and effectiveness, have proven it to be viable for volume reduction and concentration of LLRW liquids generated from nuclear-power-plant operations

Development of Nuclear Decontamination Technology Using Supercritical Fluid

Energy Technology Data Exchange (ETDEWEB)

Jung, Wonyoung; Park, Kwangheon; Park, Jihye; Lee, Donghee [Kyunghee Univ., Yongin (Korea, Republic of)

2014-05-15

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

Development of Nuclear Decontamination Technology Using Supercritical Fluid

International Nuclear Information System (INIS)

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

2014-01-01

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

Liquid Metal Engineering and Technology. Volume 1

International Nuclear Information System (INIS)

1988-01-01

These proceedings of the fourth international conference on liquid metal engineering and technology volume 1, are devided into 3 sections bearing on: - Apparatus and components for liquid metal (29 papers) - Liquid metal leaks, fires and fumes (10 papers) - Cleaning, decontamination, waste disposal (14 papers) [fr

Removal of some Fission Products from Low Level Liquid Radioactive Waste by Chemical Precipitation liquid/Co-precipitation / Phosphate Coagulant

International Nuclear Information System (INIS)

Borai, E.H.; Attallah, M.F.; Hilal, M.A.; Abo-Aly, M.M.; Shehata, F.A.

2008-01-01

In Egypt radioactive waste has been generated from various uses of radioactive materials. Presence of cesium demonstrated a major problem from the removal point of view even by conventional and advanced technologies. Selective chemical precipitation has been oriented for removal of some fission products including 137 Cs from low level liquid radioactive waste (LLLRW). The aim of the present study was focused to investigate the effectiveness of various phosphate compounds that improved the precipitation process and hence the decontamination factor. The results showed that, maximum removal of 137 Cs reaching 46.4 % using di-sodium hydrogen phosphate as a selective coagulant. It was found that significant enhancement of co-precipitation of 137 Cs (62.5 %) was obtained due to presence of Nd 3+ in the LLLRW

Treatment of low level radioactive liquid waste containing appreciable concentration of TBP degraded products.

Science.gov (United States)

Valsala, T P; Sonavane, M S; Kore, S G; Sonar, N L; De, Vaishali; Raghavendra, Y; Chattopadyaya, S; Dani, U; Kulkarni, Y; Changrani, R D

2011-11-30

The acidic and alkaline low level radioactive liquid waste (LLW) generated during the concentration of high level radioactive liquid waste (HLW) prior to vitrification and ion exchange treatment of intermediate level radioactive liquid waste (ILW), respectively are decontaminated by chemical co-precipitation before discharge to the environment. LLW stream generated from the ion exchange treatment of ILW contained high concentrations of carbonates, tributyl phosphate (TBP) degraded products and problematic radio nuclides like (106)Ru and (99)Tc. Presence of TBP degraded products was interfering with the co-precipitation process. In view of this a modified chemical treatment scheme was formulated for the treatment of this waste stream. By mixing the acidic LLW and alkaline LLW, the carbonates in the alkaline LLW were destroyed and the TBP degraded products got separated as a layer at the top of the vessel. By making use of the modified co-precipitation process the effluent stream (1-2 μCi/L) became dischargeable to the environment after appropriate dilution. Based on the lab scale studies about 250 m(3) of LLW was treated in the plant. The higher activity of the TBP degraded products separated was due to short lived (90)Y isotope. The cement waste product prepared using the TBP degraded product was having good chemical durability and compressive strength. Copyright © 2011 Elsevier B.V. All rights reserved.

Precipitation-filtering technology for uranium waste solution generated on washing-electrokinetic decontamination

Energy Technology Data Exchange (ETDEWEB)

Kim, Gye-Nam, E-mail: kimsum@kaeri.re.kr; Park, Uk-Ryang; Kim, Seung-Soo; Moon, Jei-Kwon

2015-05-15

Graphical abstract: A recycling process diagram for the volume reduction of waste solution generated from washing-electrokinetic decontamination. - Highlights: • A process for recycling a waste solution generated was developed. • The total metal precipitation rate by NaOH in a supernatant after precipitation was the highest at pH 9. • The uranium radioactivity in the treated solution upon injection of 0.2 g of alum was lower. • After drying, the volume of sludge was reduced to 35% of the initial sludge volume. - Abstract: Large volumes of uranium waste solution are generated during the operation of washing-electrokinetic decontamination equipment used to remove uranium from radioactive soil. A treatment technology for uranium waste solution generated upon washing-electrokinetic decontamination for soil contaminated with uranium has been developed. The results of laboratory-size precipitation experiments were as follows. The total amount of metal precipitation by NaOH for waste solution was highest at pH 11. Ca(II), K(I), and Al(III) ions in the supernatant partially remained after precipitation, whereas the concentration of uranium in the supernatant was below 0.2 ppm. Also, when NaOH was used as a precipitant, the majority of the K(I) ions in the treated solution remained. The problem of CaO is to need a long dissolution time in the precipitation tank, while Ca(OH){sub 2} can save a dissolution time. However, the volume of the waste solution generated when using Ca(OH){sub 2} increased by 8 mL/100 mL (waste solution) compared to that generated when using CaO. NaOH precipitant required lower an injection volume lower than that required for Ca(OH){sub 2} or CaO. When CaO was used as a precipitant, the uranium radioactivity in the treated solution at pH 11 reached its lowest value, compared to values of uranium radioactivity at pH 9 and pH 5. Also, the uranium radioactivity in the treated solution upon injection of 0.2 g of alum with CaO or Ca(OH){sub 2} was

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

Energy Technology Data Exchange (ETDEWEB)

Waysbort, Daniel [Israel Institute for Biological Research, PO Box 19, Ness-Ziona 74100 (Israel); McGarvey, David J. [R and T Directorate, Edgewood Chemical and Biological Center (ECBC), Aberdeen Proving Ground-Edgewood Area, MD 21010 (United States)], E-mail: david.mcgarvey@us.army.mil; Creasy, William R.; Morrissey, Kevin M.; Hendrickson, David M. [SAIC, P.O. Box 68, Gunpowder Branch, Aberdeen Proving Ground, MD 21010 (United States); Durst, H. Dupont [R and T Directorate, Edgewood Chemical and Biological Center (ECBC), Aberdeen Proving Ground-Edgewood Area, MD 21010 (United States)

2009-01-30

A decontamination system for chemical warfare agents was developed and tested that combines a liquid decontamination reagent solution with solid sorbent particles. The components have fewer safety and environmental concerns than traditional chlorine bleach-based products or highly caustic solutions. The liquid solution, based on Decon Green{sup TM}, has hydrogen peroxide and a carbonate buffer as active ingredients. The best solid sorbents were found to be a copolymer of ethylene glycol dimethacrylate and n-lauryl methacrylate (Polytrap 6603 Adsorber); or an allyl methacrylate cross-linked polymer (Poly-Pore E200 Adsorber). These solids are human and environmentally friendly and are commonly used in cosmetics. The decontaminant system was tested for reactivity with pinacolyl methylphosphonofluoridate (Soman, GD), bis(2-chloroethyl)sulfide (Mustard, HD), and S-(2-diisopropylaminoethyl) O-ethyl methylphosphonothioate (VX) by using NMR Spectroscopy. Molybdate ion (MoO{sub 4}{sup -2}) was added to the decontaminant to catalyze the oxidation of HD. The molybdate ion provided a color change from pink to white when the oxidizing capacity of the system was exhausted. The decontaminant was effective for ratios of agent to decontaminant of up to 1:50 for VX (t{sub 1/2} {<=} 4 min), 1:10 for HD (t{sub 1/2} < 2 min with molybdate), and 1:10 for GD (t{sub 1/2} < 2 min). The vapor concentrations of GD above the dry sorbent and the sorbent with decontamination solution were measured to show that the sorbent decreased the vapor concentration of GD. The E200 sorbent had the additional advantage of absorbing aqueous decontamination solution without the addition of an organic co-solvent such as isopropanol, but the rate depended strongly on mixing for HD.

Study of shrimp shell derivatives for treating of low-level radioactive liquid wastes

Energy Technology Data Exchange (ETDEWEB)

Hayeripour, S. [Tonkabon Islamic Azad Univ., Tonkabon (Iran, Islamic Republic of). College of the Environment; Malmasi, S. [North Tehran Islamic Azad Univ., Tehran (Iran, Islamic Republic of). College of the Environment

2006-07-01

Chitin derivatives can be used to treat liquid wastes that include heavy metals of radionuclides. In this study, 4 types of chitin derivatives from shrimp shell waste were investigated for their potential in decontaminating and treating low-level radioactive liquid waste (LLW). The adsorption of caesium (Cs); cobalt (Co); and manganese (Mn) isotopes on chitin derivatives were investigated using a batch and column system with variations in diameter, pH, and length of treatment. Chitin derivatives included shrimp shells; de-mineralized shrimp shells; chitin extracted from shrimp shells; and chitosan extracted from shrimp shell waste. Three types of simulated solutions were prepared to study and compare adsorption performance: (1) a mono cationic solution consisting of stable isotopes; (2) a solution containing 3 stable cations; and (3) a simulated radioactive waste containing Cs-137, Co-60, and Mn-54. Results of the experiments showed that all 4 chitin derivatives were capable of adsorbing the isotopes. Despite its low pH, chitosan showed the highest adsorption efficiency. It was concluded that shrimps shells provided unreliable results under different operating conditions. The demineralized shells were suitable for removing Co from solutions. Row shells were not recommended as a suitable adsorbent for radionuclides removal. 14 refs., 2 tabs., 6 figs.

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 Hot Cell Radioactive Waste Concept of Forschungszentrum Juelich

International Nuclear Information System (INIS)

Pott, G.; Halaszovich, St.

1999-01-01

During the last 30 years extensive scientific examinations on radioactive metals,ceramics and fuel elements have been carried out, so that a high volume of waste has resulted. Also from the dismantling of irradiated facilities metallics waste has o be handed. Prior for equipment repair the hot cell involved has to be decontaminated and a large amount of lower active waste is produced. The waste is collected for conditioning and storing. There are different categories as: low active liquid waste, low active burnable waste, fuel waste, low and high active metallic waste. For each waste category special transport container are used. For the volume reduction our Waste Department is equipped with special facilities e.g.: furnace for burning, drying, liquids evaporators, hydraulic press for pelletizing, decontamination box for the dismantling ad cleaning of components. After conditioning the waste will be stored on site or transported to final storage in a salt mine (ERAM) . Special documentation has to be done for the acceptance of this waste

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

A study on implementation plan of decontamination and decommissioning R and D and evaluation of KAERI soil decontamination process

International Nuclear Information System (INIS)

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

2001-08-01

A. Decontamination Technology Development of Uranium Conversion Facility. Understanding of uranium conversion facility and related decontamination technologies, and analysis of current status of decontamination technologies. Establishment of the objective and research items of the middle and long term R and D project. Discussion of the erformance plan and about the methodology for connection with the project of environmental restoration of uranium conversion facility B. Treatment Technology Development of Uranium Sludge Analysis of the domestic and overseas research development status. Suggestion of treatment methodology of uranium slurry and cooperative R and D among industries, universities and research institute. Establishment of the objective and research items of the middle and long term R and D project. Discussion about the performance plan and about the methodology for connection with the project of environmental restoration of uranium conversion facility C. Decommissioning Technology Development Analysis of the domestic and overseas research development status and the overview of decommissioning technologies. Establishment of the objective and research items of the middle and long term R and D project. Discussion about the performance plan and about the methodology for connection with the project of TRIGA decommissioning D. Evaluation of KAERI Soil Decontamination Technology. Evaluation of soil decontamination process and the liquid decontamination waste treatment technology. Performance of soil decontamination test using solvent flushing test equipment for evaluation of residual radioactivity after decontami- nation and modeling of the results

A study on implementation plan of decontamination and decommissioning R and D and evaluation of KAERI soil decontamination process

Energy Technology Data Exchange (ETDEWEB)

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

2001-08-01

A. Decontamination Technology Development of Uranium Conversion Facility. Understanding of uranium conversion facility and related decontamination technologies, and analysis of current status of decontamination technologies. Establishment of the objective and research items of the middle and long term R and D project. Discussion of the erformance plan and about the methodology for connection with the project of environmental restoration of uranium conversion facility B. Treatment Technology Development of Uranium Sludge Analysis of the domestic and overseas research development status. Suggestion of treatment methodology of uranium slurry and cooperative R and D among industries, universities and research institute. Establishment of the objective and research items of the middle and long term R and D project. Discussion about the performance plan and about the methodology for connection with the project of environmental restoration of uranium conversion facility C. Decommissioning Technology Development Analysis of the domestic and overseas research development status and the overview of decommissioning technologies. Establishment of the objective and research items of the middle and long term R and D project. Discussion about the performance plan and about the methodology for connection with the project of TRIGA decommissioning D. Evaluation of KAERI Soil Decontamination Technology. Evaluation of soil decontamination process and the liquid decontamination waste treatment technology. Performance of soil decontamination test using solvent flushing test equipment for evaluation of residual radioactivity after decontami- nation and modeling of the results.

A analysis of cementation technology for liquid radioactive-waste in PWR NPPs

International Nuclear Information System (INIS)

Chen Liang; Chen Li; Li Junhua

2009-01-01

Cementation is one of the most popular solidification technology for the low-and-intermediate level liquid radioactive waste. It has been applied in all of domestic PWR NPPs. The process characteristics and operation of the cementations in the different NPPs are introduced,and the advantage and disadvantage of the cementation are analyzed in this paper. A drum and a cask are compared as a package of the solidified waste, the drum can decrease over 50% final volume of the waste, furthermore the cost for manufacture and transportation for this drum is more cheaper than the cask, but an additional shielding may be necessary for the waste with higher level radioactivity that is packed in drum. More waste can be contained if an appropriate in-drum mixer is used while secondary waste will be unavoidable if the out-drum mixing is adopted. A carriage can make it easier to decontaminate on the surface of equipment and on the floor, furthermore the carriage is more economical than a roller conveyor in manufacture and maintenance. The cementation recipe for the waste should be optimized and additive material should be as less as possible to increase the containing rate of the waste. (authors)

Water quality for liquid wastes

International Nuclear Information System (INIS)

Mizuniwa, Fumio; Maekoya, Chiaki; Iwasaki, Hitoshi; Yano, Hiroaki; Watahiki, Kazuo.

1985-01-01

Purpose: To facilitate the automation of the operation for a liquid wastes processing system by enabling continuous analysis for the main ingredients in the liquid wastes accurately and rapidly. Constitution: The water quality monitor comprises a sampling pipeway system for taking out sample water for the analysis of liquid wastes from a pipeway introducing liquid wastes to the liquid wastes concentrator, a filter for removing suspended matters in the sample water and absorption photometer as a water quality analyzer. A portion of the liquid wastes is passed through the suspended matter filter by a feedpump. In this case, sulfate ions and chloride ions in the sample are retained in the upper portion of a separation color and, subsequently, the respective ingredients are separated and leached out by eluting solution. Since the leached out ingredients form ferric ions and yellow complexes respectively, their concentrations can be detected by the spectrum photometer. Accordingly, concentration for the sodium sulfate and sodium chloride in the liquid wastes can be analyzed rapidly, accurately and repeatedly by which the water quality can be determined rapidly and accurately. (Yoshino, Y.)

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.

The treatment of radioactive waste with reverse osmosis membrane

International Nuclear Information System (INIS)

Hendro

1997-01-01

The study of liquid waste characteristic and performance of reverse osmosis for treatment of liquid radioactive waste had been taken. Waste simulation was used to contain of 100 ppm strontium, 100 ppm cesium, pH between 5 and 6, and dry extract of 0.11 g/l, with operating condition of feed solution pressure 100 psi, temperature 25 o C, spiral wound composite membrane modules and area of membrane was 0,3042 m 2 . Results of the experiment indicated that the decontamination factor obtained between 9.3 and 15.4 for strontium, and 7,3 and 7,9 for cesium. From the beginning until one hour of operation decontamination factor increased to 53,8% for strontium and 4,1% for cesium, and permeate flux decreased at operating time more than 12 hours. Decontamination factor of process can be increased by using the series of osmosis unit (author)

Treatment of radioactive liquid wastes at the Boris Kidric Institute of Nuclear Sciences at Vinca, Yugoslavia; Obrada radioaktivnih otpadnih voda

Energy Technology Data Exchange (ETDEWEB)

Jankovic, O [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Serbia and Montenegro)

1969-07-01

A survey of the past work on decontamination and disposal of radioactive liquid wastes is given. The procedure of collecting and disposal of radioactive liquid wastes being formed are described. Also a general view of tested and developed methods of coprecipitation and ion exchange for removal of radionuclides from liquid wastes is reported. Scheme of experimental plant based on precipitation processes and ion exchange, capacity 100 1/h, that should start to operate at the end of 1969 has been illustrated (author) [Serbo-Croat] Dat je prikaz dosadasnjeg rada na problemima dekontaminacije i odlaganja radioaktivnih otpadnih voda. Opisani su postupci sakupljanja i odlaganja nastalih radioaktivnih voda. Dat je pregled ispitivanih i razvijanih metoda koprecipitacije-talozenja i jonske izmene za uklanjanje radionuklida iz otpadnih voda. Prikazana je shema eksperimentalnog postrojenja baziranog na procesima talozenja i jonske izmene, kapaciteta 100 1/cas, koje treba da bude pusteno u pogon krajem 1969. godine (author)

The separation of silica nanoparticle by cetyltrimethylammonium bromide from decontamination foam waste

International Nuclear Information System (INIS)

Choi, Man Soo; Yoon, In Ho; Jung, Chong Hun; Moon, Jei Kwon; Choi, Wang Kyu

2016-01-01

Decontamination foam has been considered as a potential application for the cleaning of radioactive contaminant in the field of metallic walls, overhead surfaces, and complex components. Moreover, foam decontamination could generate the low secondary waste amount owing to its volume expansion. In order to increase the decontamination efficiency, it is essential to improve the foam stability with low amount of chemical decontamination agent. Yoon et al. reported that the silica nanoparticle containing surfactant increased the foam stability compared to only surfactant solution[3]. Nanoparticle has been used with surfactant, which they adsorb at fluid/fluid interface, to stabilize emulsions or bubbles in foams. Despite of improving foam stability, they still used the surfactant, silica nanoparticle (1 wt%), and viscosifier. In addition, it is difficult to separate silica nanoparticle from decontamination solution. Because nanoparticles differ from classical solid particles due to smaller particle size and their specific properties. Thus, the separation method for nanoparticle should be also developed with high recovery rates. The flocculation of silica nanoparticle added by CTAB could be quickly achieved for only 30 min. The particle size of SiO_2 was larger as CTAB amount increased, and SiO_2 contents in the top solution were decreased after centrifugation

The separation of silica nanoparticle by cetyltrimethylammonium bromide from decontamination foam waste

Energy Technology Data Exchange (ETDEWEB)

Choi, Man Soo; Yoon, In Ho; Jung, Chong Hun; Moon, Jei Kwon; Choi, Wang Kyu [KAERI, Daejeon (Korea, Republic of)

2016-05-15

Decontamination foam has been considered as a potential application for the cleaning of radioactive contaminant in the field of metallic walls, overhead surfaces, and complex components. Moreover, foam decontamination could generate the low secondary waste amount owing to its volume expansion. In order to increase the decontamination efficiency, it is essential to improve the foam stability with low amount of chemical decontamination agent. Yoon et al. reported that the silica nanoparticle containing surfactant increased the foam stability compared to only surfactant solution[3]. Nanoparticle has been used with surfactant, which they adsorb at fluid/fluid interface, to stabilize emulsions or bubbles in foams. Despite of improving foam stability, they still used the surfactant, silica nanoparticle (1 wt%), and viscosifier. In addition, it is difficult to separate silica nanoparticle from decontamination solution. Because nanoparticles differ from classical solid particles due to smaller particle size and their specific properties. Thus, the separation method for nanoparticle should be also developed with high recovery rates. The flocculation of silica nanoparticle added by CTAB could be quickly achieved for only 30 min. The particle size of SiO{sub 2} was larger as CTAB amount increased, and SiO{sub 2} contents in the top solution were decreased after centrifugation.

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

International Nuclear Information System (INIS)

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

1987-01-01

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

Waste treatment

International Nuclear Information System (INIS)

Davies, D.; Hooper, E.W.

1981-01-01

In the treatment of wastes, such as liquid radioactive effluents, it is known to remove radionuclides by successive in situ precipitation of cobalt sulphide, an hydroxide, barium sulphate and a transition element ferrocyanide, followed by separation of the thereby decontaminated effluent. In this invention, use is made of precipitates such as obtained above in the treatment of further fresh liquid radioactive effluent, when it is found that the precipitates have additional capacity for extracting radionuclides. The resulting supernatant liquor may then be subjected to a further precipitation treatment such as above. Decontamination factors for radionuclides of Ce, Ru, Sr and Cs have been considerably enhanced. (author)

Precipitation process for supernate decontamination

International Nuclear Information System (INIS)

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

1982-11-01

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

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.

Update of the management strategy for Oak Ridge National Laboratory Liquid Low-Level Waste

International Nuclear Information System (INIS)

Robinson, S.M.; Abraham, T.J.; DePaoli, S.M.; Walker, A.B.

1995-04-01

The strategy for management of the Oak Ridge National Laboratory's (ORNL) radioactively contaminated liquid waste was reviewed in 1991. The latest information available through the end of 1990 on waste characterization, regulations, US Department of Energy (DOE) budget guidance, and research and development programs was evaluated to determine how the strategy should be revised. Few changes are needed to update the strategy to reflect new waste characterization, research, and regulatory information. However, recent budget guidance from DOE indicates that minimum funding will not be sufficient to accomplish original objectives to upgrade the liquid low-level waste (LLLW) system to comply with the Federal Facilities Agreement, provide long-term LLLW treatment capability, and minimize environmental, safety, and health risks. Options are presented that might allow the ORNL LLLW system to continue operations temporarily, but they would significantly reduce its capabilities to handle emergency situations, provide treatment for new waste streams, and accommodate waste from the Environmental Restoration Program and from decontamination and decommissioning of surplus facilities. These options are also likely to increase worker radiation exposure, risk of environmental insult, and generation of solid waste for on-site and off-site disposal/storage beyond existing facility capacities. The strategy will be fully developed after receipt of additional guidance. The proposed budget limitations are too severe to allow ORNL to meet regulatory requirements or continue operations long term

Long-term decontamination engineering study. Volume 1

Energy Technology Data Exchange (ETDEWEB)

Geuther, W.J.

1995-04-03

This report was prepared by Westinghouse Hanford Company (WHC) with technical and cost estimating support from Pacific Northwest Laboratories (PNL) and Parsons Environmental Services, Inc. (Parsons). This engineering study evaluates the requirements and alternatives for decontamination/treatment of contaminated equipment at the Hanford Site. The purpose of this study is to determine the decontamination/treatment strategy that best supports the Hanford Site environmental restoration mission. It describes the potential waste streams requiring treatment or decontamination, develops the alternatives under consideration establishes the criteria for comparison, evaluates the alternatives, and draws conclusions (i.e., the optimum strategy for decontamination). Although two primary alternatives are discussed, this study does identify other alternatives that may warrant additional study. hanford Site solid waste management program activities include storage, special processing, decontamination/treatment, and disposal facilities. This study focuses on the decontamination/treatment processes (e.g., waste decontamination, size reduction, immobilization, and packaging) that support the environmental restoration mission at the Hanford Site.

Long-term decontamination engineering study. Volume 1

International Nuclear Information System (INIS)

Geuther, W.J.

1995-01-01

This report was prepared by Westinghouse Hanford Company (WHC) with technical and cost estimating support from Pacific Northwest Laboratories (PNL) and Parsons Environmental Services, Inc. (Parsons). This engineering study evaluates the requirements and alternatives for decontamination/treatment of contaminated equipment at the Hanford Site. The purpose of this study is to determine the decontamination/treatment strategy that best supports the Hanford Site environmental restoration mission. It describes the potential waste streams requiring treatment or decontamination, develops the alternatives under consideration establishes the criteria for comparison, evaluates the alternatives, and draws conclusions (i.e., the optimum strategy for decontamination). Although two primary alternatives are discussed, this study does identify other alternatives that may warrant additional study. hanford Site solid waste management program activities include storage, special processing, decontamination/treatment, and disposal facilities. This study focuses on the decontamination/treatment processes (e.g., waste decontamination, size reduction, immobilization, and packaging) that support the environmental restoration mission at the Hanford Site

A study on the treatment of radioactive liquid wastes using synthetic by air intake system

International Nuclear Information System (INIS)

Kim, T. G.; Lee, Y. H.; An, S. J.; Son, J. S.; Hong, K. P.

2003-01-01

In this study based on the mass transfer theory, experiments for the evaporation rates depending on various conditions were carried out through the operation of the existing Natural Evaporation Facility in KAERI. Evaporation media were made of the cotton and polyester. Air circulation in the facility was forced by exhausting fans. The evaporation rate and the decontamination factor were calculated by the result of experiment. The evaporation rate increased as the flow rate of air supply, the feed rate of liquid waste, and the temperature of supplied air increased. As for the humility of supplied air, the evaporation rate was getting higher as the humidity was getting lower. As the result of this study, operation conditions of the Natural Evaporation Facility are optimized as follows; The air temperature above 8C .deg., the air humidity below 70%, the air flow rate 1.14-1.47 m/sec, and the liquid waste feed rate 4.6l/hr.m 2 . The decontamination factor and the radioactivity are 5.1x10 3 and 4.7x10 -13 μCi/ml respectively, at the above mentioned optimum operation conditions. The air factor in the Dalton's equation for evaporation was determined from results of experiment on the temperature, the humidity, and the flow rate of supplied air as following; Eh=(0.0168+0.0141V)ΔH

A study on the treatment of radioactive liquid wastes using synthetic by air intake system

Energy Technology Data Exchange (ETDEWEB)

Kim, T. G.; Lee, Y. H.; An, S. J.; Son, J. S.; Hong, K. P. [KAERI, Taejon (Korea, Republic of)

2003-07-01

In this study based on the mass transfer theory, experiments for the evaporation rates depending on various conditions were carried out through the operation of the existing Natural Evaporation Facility in KAERI. Evaporation media were made of the cotton and polyester. Air circulation in the facility was forced by exhausting fans. The evaporation rate and the decontamination factor were calculated by the result of experiment. The evaporation rate increased as the flow rate of air supply, the feed rate of liquid waste, and the temperature of supplied air increased. As for the humility of supplied air, the evaporation rate was getting higher as the humidity was getting lower. As the result of this study, operation conditions of the Natural Evaporation Facility are optimized as follows; The air temperature above 8C .deg., the air humidity below 70%, the air flow rate 1.14-1.47 m/sec, and the liquid waste feed rate 4.6l/hr.m{sup 2}. The decontamination factor and the radioactivity are 5.1x10{sup 3} and 4.7x10{sup -13}{mu}Ci/ml respectively, at the above mentioned optimum operation conditions. The air factor in the Dalton's equation for evaporation was determined from results of experiment on the temperature, the humidity, and the flow rate of supplied air as following; Eh=(0.0168+0.0141V){delta}H.

Liquid abrasive pressure pot scoping tests report

International Nuclear Information System (INIS)

Archibald, K.E.

1996-01-01

The primary initiatives of the LITCO Decontamination Development group at the Idaho Chemical Process Plant (ICPP) are the development of methods to eliminate the use of sodium bearing decontamination chemicals and minimization of the amount of secondary waste generated during decontamination activities. In July of 1994, a Commerce Business Daily (CBD) announcement was issued by the INEL to determine commercial interest in the development of an in-situ liquid abrasive grit blasting system. As a result of the CBD announcement, Klieber ampersand Schulz issued an Expression of Interest letter which stated they would be interested in testing a prototype Liquid Abrasive Pressure Pot (LAPP). LITCO's Decontamination group and Kleiber ampersand Schulz entered into a Cooperative Research and Development Agreement (CRADA) in which the Decontamination Development group tested the prototype LAPP in a non-radioactive hot cell mockup. Test results are provided

Engineering study radioactive liquid waste treatment plant refurbishment

International Nuclear Information System (INIS)

Suazo, I.L.

1994-01-01

This feasibility study will investigate the opportunities, restrictions and cost impact to refurbish the existing Radioactive Liquid Waste Treatment Plant (RLWTP) while utilizing the same basic criteria that was used in the development of the new Radioactive Liquid Waste Treatment Facility (RLWTF). The objective of this study is to perform a more in-depth analysis of refurbishing the existing than has been done in the past so as to provide a basis for comparison between refurbishing the existing or constructing a new. The existing plant is located at Technical Area 50 (TA-50) within the Los Alamos National Laboratory (LANL). The initial structure was built in 1963. Over the ensuing years, the building has been modified and several additions have been constructed. In 1966, laboratories, ion exchange and pretreatment functions were added. The decontamination and decommissioning activities and ventilation equipment were added in 1984. The following assumptions are the basic parameters considered in the development of a design concept to refurbish the RLWTP: (1) Allow continued operation of the during retrofit construction. (2) Design the necessary expansion within the site constraints. (3) Satisfy National Pollutant Discharge Elimination System (NPDES) and National Emission Standards for Hazardous Air Pollutants (NESHAPS) permit conditions and other environmental regulations. (4) Comply with present DOE Orders and building code requirements. The refurbishment concept is a phased demolition and construction process

Operational experiences and upgradation of waste management facilities Trombay, India

International Nuclear Information System (INIS)

Chander, Mahesh; Bodke, S.B.; Bansal, N.K.

2001-01-01

Full text: Waste Management Facilities Trombay provide services for the safe management of radioactive wastes generated from the operation of non power sources at Bhabha Atomic Research Centre, India. The paper describes in detail the current operational experience and facility upgradation by way of revamping of existing processes equipment and systems and augmentation of the facility by way of introducing latest processes and technologies to enhance the safety. Radioactive wastes are generated from the operation of research reactors, fuel fabrication, spent fuel reprocessing, research labs. manufacture of sealed sources and labeled compounds. Use of radiation sources in the field of medical, agriculture and industry also leads to generation of assorted solid waste and spent sealed radiation sources which require proper waste management. Waste Management Facilities Trombay comprise of Effluent Treatment Plant (ETP), Decontamination Centre (DC) and Radioactive Solid Waste Management Site (RSMS). Low level radioactive liquid effluents are received at ETP. Plant has 100 M 3 /day treatment capacity. Decontamination of liquid effluents is effected by chemical treatment method using co- precipitation as a process. Plant has 1800 M 3 of storage capacity. Chemical treatment system comprises of clarifloculator, static mixer and chemical feed tanks. Plant has concentrate management facility where chemical sludge is centrifuged to effect volume reduction of more that 15. Thickened sludge is immobilized in cement matrix. Decontamination Centre caters to the need of equipment decontamination from research reactors. Process used is ultrasonic chemical decontamination. Besides this DC provides services for decontamination of protective wears. Radioactive Solid Waste Management Site is responsible for the safe management of solid waste generated at various research reactors, plants, laboratories in Bhabha Atomic Research Centre. Spent sealed radiation sources are also stored

Electrochemical ion-exchange for medium active liquid waste treatment

International Nuclear Information System (INIS)

Bridger, N.J.; Turner, A.D.

1987-01-01

Electrochemical ion-exchange has already been demonstrated to be a robust, effective process for the treatment of active liquid wastes -with high decontamination and volume reduction factors, and only a low energy requirement. The primary aim of this new programme is to scale up this process - initially to 0.1m 3 /h, and ultimately to 1 3 m/h. A new 0.4m 2 electrode module has been designed and constructed, together with 3m 3 feed tanks for the first phase of this work. Further development work is also being carried out on alternative electrode designs and fabrication methods, as well as new exchange media (including inorganic absorbers and organic chelating resins) in order to optimize selectivity performance. (author)

Development of an integrated liquid radioactive waste management system. Part of a coordinated programme on integrated radioactive waste management systems and their impact on the environment

International Nuclear Information System (INIS)

Pavlik, O.

1976-09-01

This final report discusses the theory of the air heated non-boiling evaporation and the laboratory and pilot plant experiences of simultaneous evaporation and solidification. The evaporator concentrates and dries the radioactive liquid wastes by hot air-flow circulating in closed circuit. The air is used both for heating and removal of vapours. The liquid waste becomes saturated and the salt cake is accumulated in the tank. The yield evaporation rate and the decontamination factor or 90 Sr and 137 Cs was investigated as a function to air-flow, air temperature and humidity. During the evaporation process a simultaneous cementation method was developed to fix the water soluble components of the salt cake. The leaching rate of 90 Sr and 137 Cs, the firmness and the homogeneity of the concrete was investigated

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

Decontamination of concentrated medium level radioactive wastes by a chromatographic method

International Nuclear Information System (INIS)

Faubel, W.; Mehret, R.; Menzler, P.M.

1990-01-01

The technical feasibility of partitioning concentrated nitric acid intermediate-level waste (ILWC) solutions from the Purex process into a small volume of high-level waste and a large volume of low-level waste using sorption methods is demonstrated for 1-l and 11-l batches. Cesium-134 and 137 are selectively separated with a decontamination factor (DF) > 1 x 10 5 in a newly developed suspended-bed column filled with the microporous inorganic exchanger ammonium molybdophosphate. The 125 Sb and the actinides and lanthanides (3 +) are retained with DFs between 40 and 1000 on metal oxides of Sb and Mn and on an extraction column containing n-octyl (phenyl)N,N-disobutyl carbamoyl methyl phosphine oxide, respectively. Ruthenium-106 and 60 Co are removed in a column loaded with dimethyl glyoxime and have DFs > 20. The amount of secondary wastes arising from absorber materials was estimated on the basis of 1 l experiments to be 300 kg for a 350 t/yr reprocessing plant with an ILWC volume of about 0.5 m 3 /t of heavy metal. One of the main goals was to check out the influence of a scaling up from laboratory scale to pilot plant operations. The hydraulic behaviour of the apparatus was tested for 1, 20, and 100 liters of solutions. The second important aim was to reach a decontamination of the ILWC, sufficient to meet the requirements of regulations limiting the dose to 2 mSv/h at a 1-m distance, calculations with the PROMAX program, for cementing the LLW effluent into 400-l drums at a 10 wt% loading, lead to a value of about 100 μSv/h; thus, this waste can be handled without any shielding. The secondary waste can be treated individually

The Radioactive Waste Management at Studsvik

Energy Technology Data Exchange (ETDEWEB)

Hedlund, R; Lindskog, A

1966-04-15

The report was originally prepared as a contribution to the discussions in an IAEA panel on economics of radioactive waste management held in Vienna from 13 - 17 December 1965. It contains the answers and comments to the questions of a questionnaire for the panel concerning the various operations associated with the management (collection, transport, treatment, discharge, storage, and operational monitoring) of: - radioactive liquid wastes, except high-level effluents from reactor fuel recovering operations; - solid wastes, except those produced from treatment of high level wastes; - gaseous wastes produced from treatment of the foregoing liquid and solid wastes; - equipment decontamination facilities and radioactive laundries.

The Radioactive Waste Management at Studsvik

International Nuclear Information System (INIS)

Hedlund, R.; Lindskog, A.

1966-04-01

The report was originally prepared as a contribution to the discussions in an IAEA panel on economics of radioactive waste management held in Vienna from 13 - 17 December 1965. It contains the answers and comments to the questions of a questionnaire for the panel concerning the various operations associated with the management (collection, transport, treatment, discharge, storage, and operational monitoring) of: - radioactive liquid wastes, except high-level effluents from reactor fuel recovering operations; - solid wastes, except those produced from treatment of high level wastes; - gaseous wastes produced from treatment of the foregoing liquid and solid wastes; - equipment decontamination facilities and radioactive laundries

Behavior of radioactive cesium during incineration of radioactively contaminated wastes from decontamination activities in Fukushima.

Science.gov (United States)

Fujiwara, Hiroshi; Kuramochi, Hidetoshi; Nomura, Kazutaka; Maeseto, Tomoharu; Osako, Masahiro

2017-11-01

Large volumes of decontamination wastes (DW) generated by off-site decontamination activities in Fukushima Prefecture have been incinerated since 2015. The behavior of radioactive cesium during incineration of DW was investigated at a working incineration plant. The incineration discharged bottom ash (BA) and fly ash (FA) with similar levels of radiocesium, and the leachability of the radiocesium from both types of ash was very low (incineration of contaminated municipal solid waste (CMSW) reported in earlier studies. The source of radiocesium in DW-FA is chiefly small particles derived from DW and DW-BA blown into the flue gas, not the deposition of gaseous synthesized radiocesium compounds on the surfaces of ash particles in the flue gas as observed in CMSW incineration. This source difference causes the behavior of radiocesium during waste incineration to differ between DW and CMSW. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Treatment of Low Level Radioactive Liquid Waste Containing Detergent by Biological Activated Sludge Process

International Nuclear Information System (INIS)

Zainus Salimin

2002-01-01

The treatment of low level radioactive liquid waste containing persil detergent from laundry operation of contaminated clothes by activated sludge process has been done, for alternative process replacing the existing treatment by evaporation. The detergent concentration in water solution from laundry operation is 14.96 g/l. After rinsing operation of clothes and mixing of laundry water solution with another liquid waste, the waste water solution contains about ≤ 1.496 g/l of detergent and 10 -3 Ci/m 3 of Cs-137 activity. The simulation waste having equivalent activity of Cs-137 10 -3 Ci/m 3 , detergent content (X) 1.496, 0.748, 0.374, 0.187, 0.1496 and 0.094 g/l on BOD value respectively 186, 115, 71, 48, 19, and 16 ppm was processed by activated sludge in reactor of 18.6 l capacity on ambient temperature. It is used Super Growth Bacteria (SGB) 102 and SGB 104, nitrogen and phosphor nutrition, and aeration. The result show that bacteria of SGB 102 and SGB 104 were able to degrade the persil detergent for attaining standard quality of water release category B in which BOD values 6 ppm. It was need 30 hours for X ≤ 0.187 g/l, 50 hours for 0.187 < X ≤ 0.374 g/l, 75 hours for 0.374 < X ≤ 0.748, and 100 hours for 0.748 < X ≤ 1.496 g/l. On the initial period the bacteria of SGB 104 interact most quickly to degrade the detergent comparing SGB 102. Biochemical oxidation process decontaminate the solution on the decontamination factor of 350, Cs-137 be concentrate in sludge by complexing with the bacteria wall until the activity of solution be become very low. (author)

Method of processing radioactive liquid waste

International Nuclear Information System (INIS)

Hasegawa, Akira; Kuribayashi, Hiroshi; Soda, Kenzo; Mihara, Shigeru.

1988-01-01

Purpose: To obtain satisfactory plastic solidification products rapidly and smoothly by adding oxidizers to radioactive liquid wastes. Method: Sulfuric acid, etc. are added to radioactive liquid wastes to adjust the pH value of the liquid wastes to less than 3.0. Then, ferrous sulfates are added such that the iron concentration in the liquid wastes is 100 mg/l. Then, after adjusting pH suitably to the drying powderization by adding alkali such as hydroxide, the liquid wastes are dried and powderized. The resultant powder is subjected to plastic solidification by using polymerizable liquid unsaturated polyester resins as the solidifying agent. The thus obtained solidification products are stable in view of the physical property such as strength or water proofness, as well as stable operation is possible even for those radioactive liquid wastes in which the content ingredients are unknown. (Takahashi, M.)

Radiation protection at the RA Reactor in 1989, Part -2, Decontamination, collection of treatment of fluid and solid radioactive waste, Annex 3

International Nuclear Information System (INIS)

Mandic, M.; Vukovic, Z.; Plecas, I.; Knezevic, Lj.; Lazic, S.; Bacic, S.

1989-01-01

Certain amount of solid waste results from RA reactor operation, the mean quantity of which depends on the duration of reactor operation and related activities. During repair, when reactor is not operated as well under accidental conditions, the quantity of waste is higher, dependent on the type of repair and comprehensiveness of decontamination of the working surface, contaminated tools and components. The waste is sorted and packed on the spot where they appeared according to the existing regulations and principles of radiation protection with aim to minimize unnecessary exposure of the radiation protection personnel who deals with control, transport, radioactive waste treatment and decontamination. During exceptional operations (decontamination, repair, bigger volume of contaminated material, etc.) professional staff of the Radiation protection department gives recommendations and helps in planning the actions related to repair, sorting and packaging of radioactive waste in special containers, identification of the contaminants, etc. [sr

Method of processing radioactive liquid waste

International Nuclear Information System (INIS)

Motojima, Kenji; Kawamura, Fumio.

1981-01-01

Purpose: To increase the efficiency of removing radioactive cesium from radioactive liquid waste by employing zeolite affixed to metallic compound ferrocyanide as an adsorbent. Method: Regenerated liquid waste of a reactor condensation desalting unit, floor drain and so forth are collected through respective supply tubes to a liquid waste tank, and the liquid waste is fed by a pump to a column filled with zeolite containing a metallic compound ferrocyanide, such as with copper, zinc, manganese, iron, cobalt, nickel or the like. The liquid waste from which radioactive cesium is removed is dried and pelletized by volume reducing and solidifying means. (Yoshino, Y.)

Biochemistry Oxidation Process for Treatment the Simulation of Organic Liquid Radioactive Waste

International Nuclear Information System (INIS)

Gunandjar; Zainus Salimin; Sugeng Purnomo; Ratiko

2010-01-01

The nuclear industry activities generate the organic liquid wastes such as detergent waste from laundry, solvent waste of 30% TBP (tri-n-butyl phosphate) in kerosene from purification or recovery of uranium from rejection of nuclear fuel element fabrication, and solvent waste containing D 2 EHPA (di-2-ethyl hexyl phosphoric acid) and TOPO (trioctyl phospine oxide) in kerosene from phosphoric acid purification. The wastes are included in category of the hazard and poison materials which also radioactive, so that the wastes have to be treated to detoxification of the hazard and poison materials and decontamination of the radionuclides. The research of biochemistry oxidation process for treatment the simulation of organic liquid radioactive waste from laundry using mixture of aerobe bacteria of bacillus sp, pseudomonas sp, arthrobacter sp, and aeromonas sp have been carried out. The waste containing detergent 1,496 g/Litre, activity 10 -1 Ci/m 3 , with COD (Chemical Oxygen Demand) 128, BOD (Biological Oxygen Demand) 68 and TSS (Total Suspended Solid) 1000 ppm, it is treated by biochemistry oxidation with addition of bacteria which be fed nutrition of nitrogen and phosphor, and aeration. The result show that the bacteria can decompose the detergent to become carbon dioxyde and water so that can fulfill the quality standard of water group-B with content of BOD and COD are 6 and 10 ppm respectively, the time of decomposition is needed 106 hours to be fulfill the quality standard of water. The longer of process time will give bigger the total solid content in sludge, because the biomass generated from the colony of bacteria which life and dead to so much. (author)

Electromagnetic mixed waste processing system for asbestos decontamination

International Nuclear Information System (INIS)

Kasevich, R.S.; Nocito, T.; Vaux, W.G.; Snyder, T.

1994-01-01

DOE sites contain a broad spectrum of asbestos materials (cloth, pipe lagging, sprayed insulation and other substances) which are contaminated with a combination of hazardous and radioactive wastes due to its use during the development of the US nuclear weapons complex. These wastes consist of cutting oils, lubricants, solvents, PCBs, heavy metals and radioactive contaminants. The radioactive contaminants are the activation, decay, and fission products of DOE operations. To allow disposal, the asbestos must be converted chemically, followed by removing and separating the hazardous and radioactive materials to prevent the formation of mixed wastes and to allow for both sanitary disposal and effective decontamination. Currently, no technology exists that can meet these sanitary and other objectives. An attempt was made to apply techniques that have already proved successful in the mining, oil, and metals processing industries to the development of a multi-stage process to remove and separate hazardous chemical radioactive materials from asbestos. This process uses three methods: ABCOV chemicals which converts the asbestos to a sanitary waste; dielectric heating to volatilize the organic materials; and electrochemical processing for the removal of heavy metals, RCRA wastes and radionuclides. This process will result in the destruction of over 99% of the asbestos; limit radioactive metal contamination to 0.2 Bq alpha per gram and 1 Bq beta and gamma per gram; reduce hazardous organics to levels compatible with current EPA policy for RCRA delisting; and achieve TCLP limits for all solidified waste

Radioactive wastes processing device

International Nuclear Information System (INIS)

Takamura, Yoshiyuki; Fukujoji, Seiya.

1986-01-01

Purpose: To exactly recognize the deposition state of mists into conduits thereby effectively conduct cleaning. Constitution: A drier for performing drying treatment of liquid wastes, a steam decontaminating tower for decontaminating the steams generated from the drier and a condenser for condensating the decontaminating steams are connected with each other by means of conduits to constitute a radioactive wastes processing apparatus. A plurality of pressure detectors are disposed to the conduits, the pressure loss within the conduits is determined based on the detector output and the clogged state in the conduits due to the deposition of mists is detected by the magnitude of the pressure loss. If the clogging exceeds a certain level, cleaning water is supplied to clean-up the conduits thereby keep the operation to continue always under sound conditions. (Sekiya, K.)

Healthcare liquid waste management.

Science.gov (United States)

Sharma, D R; Pradhan, B; Pathak, R P; Shrestha, S C

2010-04-01

The management of healthcare liquid waste is an overlooked problem in Nepal with stern repercussions in terms of damaging the environment and affecting the health of people. This study was carried out to explore the healthcare liquid waste management practices in Kathmandu based central hospitals of Nepal. A descriptive prospective study was conducted in 10 central hospitals of Kathmandu during the period of May to December 2008. Primary data were collected through interview, observation and microbiology laboratory works and secondary data were collected by records review. For microbiological laboratory works,waste water specimens cultured for the enumeration of total viable counts using standard protocols. Evidence of waste management guidelines and committees for the management of healthcare liquid wastes could not be found in any of the studied hospitals. Similarly, total viable counts heavily exceeded the standard heterotrophic plate count (p=0.000) with no significant difference in such counts in hospitals with and without treatment plants (p=0.232). Healthcare liquid waste management practice was not found to be satisfactory. Installation of effluent treatment plants and the development of standards for environmental indicators with effective monitoring, evaluation and strict control via relevant legal frameworks were realized.

Immobilization of organic liquid wastes

International Nuclear Information System (INIS)

Greenhalgh, W.O.

1985-01-01

This report describes a portland cement immobilization process for the disposal treatment of radioactive organic liquid wastes which would be generated in a a FFTF fuels reprocessing line. An incineration system already on-hand was determined to be too costly to operate for the 100 to 400 gallons per year organic liquid. Organic test liquids were dispersed into an aqueous phosphate liquid using an emulsifier. A total of 109 gallons of potential and radioactive aqueous immiscible organic liquid wastes from Hanford 300 Area operations were solidified with portland cement and disposed of as solid waste during a 3-month test program with in-drum mixers. Waste packing efficiencies varied from 32 to 40% and included pump oils, mineral spirits, and TBP-NPH type solvents

LABORATORY OPTIMIZATION TESTS OF TECHNETIUM DECONTAMINATION OF HANFORD WASTE TREATMENT PLANT LOW ACTIVITY WASTE OFF-GAS CONDENSATE SIMULANT

Energy Technology Data Exchange (ETDEWEB)

Taylor-Pashow, K.; Nash, C.; McCabe, D.

2014-09-29

compatible with longterm tank storage and immobilization methods. For this new application, testing is needed to demonstrate acceptable treatment sorbents and precipitating agents and measure decontamination factors for additional radionuclides in this unique waste stream. The origin of this LAW Off-Gas Condensate stream will be the liquids from the Submerged Bed Scrubber (SBS) and the Wet Electrostatic Precipitator (WESP) from the LAW melter off-gas system. The stream is expected to be a dilute salt solution with near neutral pH, and will likely contain some insoluble solids from melter carryover. The soluble components are expected to be mostly sodium and ammonium salts of nitrate, chloride, and fluoride. This stream has not been generated yet and will not be available until the WTP begins operation, but a simulant has been produced based on models, calculations, and comparison with pilot-scale tests. One of the radionuclides that is volatile and expected to be in greatest abundance in this LAW Off-Gas Condensate stream is Technetium-99 ({sup 99}Tc). Technetium will not be removed from the aqueous waste in the Hanford WTP, and will primarily end up immobilized in the LAW glass by repeated recycle of the off-gas condensate into the LAW melter. Other radionuclides that are low but are also expected to be in measurable concentration in the LAW Off-Gas Condensate are {sup 129}I, {sup 90}Sr, {sup 137}Cs, {sup 241}Pu, and {sup 241}Am. These are present due to their partial volatility and some entrainment in the off-gas system. This report discusses results of optimized {sup 99}Tc decontamination testing of the simulant. Testing examined use of inorganic reducing agents for {sup 99}Tc. Testing focused on minimizing the quantity of sorbents/reactants added, and minimizing mixing time to reach the decontamination targets in this simulant formulation. Stannous chloride and ferrous sulfate were tested as reducing agents to determine the minimum needed to convert soluble pertechnetate

Alternatives for managing wastes from reactors and post-fission operations in the LWR fuel cycle. Volume 2. Alternatives for waste treatment

International Nuclear Information System (INIS)

1976-05-01

Volume II of the five-volume report is devoted to the description of alternatives for waste treatment. The discussion is presented under the following section titles: fuel reprocessing modifications; high-level liquid waste solidification; treatment and immobilization of chop-leach fuel bundle residues; treatment of noncombustible solid wastes; treatment of combustible wastes; treatment of non-high-level liquid wastes; recovery of transuranics from non-high-level wastes; immobilization of miscellaneous non-high-level wastes; volatile radioisotope recovery and off-gas treatment; immobilization of volatile radioisotopes; retired facilities (decontamination and decommissioning); and, modification and use of selected fuel reprocessing wastes

Alternatives for managing wastes from reactors and post-fission operations in the LWR fuel cycle. Volume 2. Alternatives for waste treatment

Energy Technology Data Exchange (ETDEWEB)

1976-05-01

Volume II of the five-volume report is devoted to the description of alternatives for waste treatment. The discussion is presented under the following section titles: fuel reprocessing modifications; high-level liquid waste solidification; treatment and immobilization of chop-leach fuel bundle residues; treatment of noncombustible solid wastes; treatment of combustible wastes; treatment of non-high-level liquid wastes; recovery of transuranics from non-high-level wastes; immobilization of miscellaneous non-high-level wastes; volatile radioisotope recovery and off-gas treatment; immobilization of volatile radioisotopes; retired facilities (decontamination and decommissioning); and, modification and use of selected fuel reprocessing wastes. (JGB)

Liquidation of wastes as tuition topic

International Nuclear Information System (INIS)

Kolar, K.; Hysplerova, L.; Holy, I.

1999-01-01

Authors deal in this paper with tuition project aimed on the liquidation of wastes. Structure of project includes next thematic complex: classification of inorganic and organic wastes; characterization of wastes and proposition for their liquidation (detoxication) or recyclation; chemical (physical) nature of neutralize of inorganic and organic wastes; general method of neutralize of wastes; analytical methods necessary for control of course of neutralize (detoxication) of wastes. This tuition project allows for students to know manipulation with wastes and methods of their liquidation from ecologic point of view

Decontamination demonstration facility (D.D.F) modularization/mobility study

International Nuclear Information System (INIS)

FitzPatrick, V.F.; Butts, H.L.; Moles, R.G.; Lundgren, R.A.

1980-11-01

The component decontamination technology, developed under the DOE sponsored TRU Waste Decontamination Program, has potential benefits to nuclear utility owners in four strategic areas: (1) Meeting ALARA Criteria for Maintenance/Operations; (2) Management of wastes and waste forms; (3) Accident Response; (4) Decommissioning. The most significant step in transferring this technology directly to the nuclear industry is embodied in the TMI Decontamination Demonstration Facility

Ion exchange media testing for processing recyclable and nonrecyclable liquids at Diablo Canyon Power Plant

International Nuclear Information System (INIS)

James, K.L.; Miller, C.C.

1989-01-01

This paper reports on several ion exchange materials tested for processing nonrecyclable and recyclable liquid wastes at Diablo Canyon Power Plant. These ion exchange materials include inorganic Durasil media, natural and synthetic zeolites, and various organic resins. Additional tests were performed using a polyelectrolyte pretreatment technique to enhance processing of liquid wastes by ion exchange. A 9:1 ratio of cation to anion resin, consisting of IRN-77 and Sybron A-642 was effective in decontaminating cesium and cobalt radionuclides for low conductivity nonrecyclable liquids. A mixture of zeolite and Durasil media was most effective in removing cesium and cobalt from nonrecyclable high conductivity liquids. The experimental Dow resins achieved the best results in decontaminating recyclable liquids and minimized the effluent levels of chlorides, sulfates, and silica

Application of inorganic ion exchangers for low and medium activity radioactive effluent decontamination

International Nuclear Information System (INIS)

Dozol, J.F.; Eymard, S.; Gambade, R.; La Rosa, G.

1986-01-01

This study proposes an alternative pretreatment or treatment for low and medium activity liquid wastes, allowing to improve the quality of containment and decrease the cost of storage. Inorganic ion exchangers are used to remove alpha emitters and long lived fission products and concentrate them in a small volume; these exchangers can be converted into a stable matrix by thermal treatment. This treatment, at least for some liquid wastes, don't exclude a complementary decontamination by chemical precipitation. Sludges, arising from precipitation, exempt from alpha emitters and long lived fission products can be stored in a shallow land burial. This study includes two parts: - Measurements of distribution coefficients for the main nuclides in order to choose, for each liquid wastes, the most suitable ion exchanger. - Estimation of performances of selected inorganic ion exchangers, from tests of percolation of genuine effluents

Membrane technologies for liquid radioactive waste treatment

International Nuclear Information System (INIS)

Chmielewski, A.G.; Harasimowicz, M.; Zakrzewska-Trznadel, G.

1998-01-01

At Institute of Nuclear Chemistry and Technology (INCT) the membrane method for purification of radioactive wastes applied such processes as ultrafiltration (UF), 'seeded' ultrafiltration and reverse osmosis (RO) was developed. On the basis of the results obtained in laboratory experiments the pilot plant for radioactive effluents treatment was built. The plant was composed of UF unit (AMICON H 26P30 capillary module) and two RO units (NITTO NTR 739 HF S-4 spiral wound LPRO modules). The capacity of the pilot plant was up to 200 L/h and the specific activity of wastes purified in the system - below 10 4 Bq/L. Decontamination factor for entire system is higher than 5 x10 3 . Another possibility for radioactive wastes treatment is membrane distillation (MD), non-isothermal process employing hydrophobic polymer membrane, which is developed at INCT now. Preliminary tests with liquid radwaste were carried out on laboratory unit with permeation test-cell holding flat sheet membrane. As a hydrophobic barrier membranes made of two polymers were used: polytetrafluoroethylene (PTFE) and polypropylene (PP). The process was arranged in direct contact membrane distillation configuration. The permeate condensed directly in the cold stream (distilled water) and retentate was enriched in radionuclides. The further experiments carried out with capillary module BFMF 06-30-33 (Euro-Sep Ltd.) with polypropylene capillaries, diameter 0.33 mm and cut off 0.6 μm proved previous results. A pilot plant employing GORE-TEX membrane distillation was constructed. The plant can clean the low-level radioactive wastes from nuclear centre, at a throughput about 0.05 m 3 /h

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.)

Treatment plan for aqueous/organic/decontamination wastes under the Oak Ridge Reservation FFCA Development, Demonstration, Testing, and Evaluation Program

International Nuclear Information System (INIS)

Backus, P.M.; Benson, C.E.; Gilbert, V.P.

1994-08-01

The U.S. Department of Energy (DOE) Oak Ridge Operations Office and the U.S. Environmental Protection Agency (EPA)-Region IV have entered into a Federal Facility Compliance Agreement (FFCA) which seeks to facilitate the treatment of low-level mixed wastes currently stored at the Oak Ridge Reservation (ORR) in violation of the Resource, Conservation and Recovery Act Land Disposal Restrictions. The FFCA establishes schedules for DOE to identify treatment for wastes, referred to as Appendix B wastes, that current have no identified or existing capacity for treatment. A development, demonstration, testing, and evaluation (DDT ampersand E) program was established to provide the support necessary to identify treatment methods for mixed was meeting the Appendix B criteria. The Program has assembled project teams to address treatment development needs for major categories of the Appendix B wastes based on the waste characteristics and possible treatment technologies. The Aqueous, Organic, and Decontamination (A OE D) project team was established to identify pretreatment options for aqueous and organic wastes which will render the waste acceptable for treatment in existing waste treatment facilities and to identify the processes to decontaminate heterogeneous debris waste. In addition, the project must also address the treatment of secondary waste generated by other DDT ampersand E projects. This report details the activities to be performed under the A OE D Project in support of the identification, selection, and evaluation of treatment processes. The goals of this plan are (1) to determine the major aqueous and organic waste streams requiring treatment, (2) to determine the treatment steps necessary to make the aqueous and organic waste acceptable for treatment in existing treatment facilities on the ORR or off-site, and (3) to determine the processes necessary to decontaminate heterogeneous wastes that are considered debris

Presolidification treatment of decontamination wastes

International Nuclear Information System (INIS)

Habayeb, M.A.

1982-02-01

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

Treatment options of low level liquid waste of ETP origin by synthetic zeolites

International Nuclear Information System (INIS)

Singh, I.J.; Jain, Savita; Sathi Sasidharan, N.; Deshingkar, D.S.

2001-08-01

Mixture of synthetic zeolites, AR1, 4A and 13X of Indian origin were tested in a single fixed bed column operation for the treatment of low level liquid waste received at Effluents Treatment Plant (ETP) Trombay, under dynamic conditions. The mixed bed of zeolites was highly effective in decontaminating thousands of bed volumes of waste stream from radio cesium, radio strontium and gross beta gamma activity. High volume reduction factors, upwards of 10,000 are available in this process compared to less than 100 available with chemical precipitation process, currently followed. Containment of entrapped activity in zeolite bed was studied by solidifying them in Portland cement matrix as stable waste form. Incorporation of minerals like vermiculite as minor additive for improving the leaching characteristics of the final waste form was evaluated. Zeolite incorporated cement blocks were subjected to leach tests in distilled water for over 200 days to assess the incremental and cumulative leach rates of individual activity components. Leachability index of radio cesium and strontium were computed, which indicated the suitability of the matrix for safe shallow land burial. (author)

Characterization of the solid radioactive waste from Cernavoda NPP

International Nuclear Information System (INIS)

Iordache, M.; Lautaru, V.; Bujoreanu, D.

2005-01-01

During the operation of a nuclear plant significant quantities of radioactive waste result that have a very large diversity. At Cernavoda NPP large amounts of wastes are either non-radioactive wastes or radioactive wastes, each of these being managed completely different from each other. For a CANDU type reactor, the occurrence of radioactive wastes is due to contamination with the following types of radioactive substances: - fission products resulting from nuclear fuel burning; - activated products from materials composing the technological systems; - activated products in process fluids. Radioactive wastes can be in solid, liquid or gas form. At Cernavoda NPP the solid wastes represent about 70% of the waste volume which is produced during plant operation and as a consequence of maintenance and decontamination operations. The most important types of solid wastes that are obtained and then handled, processed (if necessary) and temporarily stored are: solid low-level radioactive wastes (classified as compactible and non-compactible), solid medium radioactive wastes, spent resins, used filters and filter cartridges. The liquid radioactive waste class includes organic liquids (used oil, scintillator liquids and used solvents) and aqueous wastes resulting from process system operating, from decontamination and maintenance operations. Radioactive gas wastes occur subsequently to the fission process inside the fuel elements as well as due to the neutron activation of process fluids in the reactor systems. As result of plant operation, iodine, noble gases, tritium and radioactive particles occur and are passed toward the ventilation stack in a controlled manner so that environmental release of radioactive materials with concentrations exceeding the maximum permissible level could not occur. (authors)

Full system decontamination feasibility studies

International Nuclear Information System (INIS)

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

1988-01-01

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

Liquid secondary waste: Waste form formulation and qualification

Energy Technology Data Exchange (ETDEWEB)

Cozzi, A. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Dixon, K. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hill, K. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nichols, R. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-07-31

The Hanford Site Effluent Treatment Facility (ETF) currently treats aqueous waste streams generated during site cleanup activities. When the Hanford Tank Waste Treatment and Immobilization Plant (WTP) begins operations, including Direct Feed Low Activity Waste (DFLAW) vitrification, a liquid secondary waste (LSW) stream from the WTP will need to be treated. The volume of effluent for treatment at the ETF will increase significantly. The powdered salt waste form produced by the ETF will be replaced by a stabilized solidified waste form for disposal in Hanford’s Integrated Disposal Facility (IDF). Washington River Protection Solutions is implementing a Secondary Liquid Waste Immobilization Technology Development Plan to address the technology needs for a waste form and solidification process to treat the increased volume of waste planned for disposal at the IDF. Waste form testing to support this plan is composed of work in the near term to provide data as input to a performance assessment (PA) for Hanford’s IDF. In 2015, three Hanford Liquid Secondary Waste simulants were developed based on existing and projected waste streams. Using these waste simulants, fourteen mixes of Hanford Liquid Secondary Waste were prepared and tested varying the waste simulant, the water-to-dry materials ratio, and the dry materials blend composition.1 In FY16, testing was performed using a simulant of the EMF process condensate blended with the caustic scrubber—from the Low Activity Waste (LAW) melter—, processed through the ETF. The initial EMF-16 simulant will be based on modeling efforts performed to determine the mass balance of the ETF for the DFLAW.2 The compressive strength of all of the mixes exceeded the target of 3.4 MPa (500 psi) to meet the requirements identified as potential IDF Waste Acceptance Criteria in Table 1 of the Secondary Liquid Waste Immobilization Technology Development Plan.3 The hydraulic properties of the waste forms tested (hydraulic conductivity

Radioactive liquid waste solidifying device

International Nuclear Information System (INIS)

Uchiyama, Yoshio.

1987-01-01

Purpose: To eliminate the requirement for discharge gas processing and avoid powder clogging in a facility suitable to the volume-reducing solidification of regenerated liquid wastes containing sodium sulfate. Constitution: Liquid wastes supplied to a liquid waste preheater are heated under a pressure higher than the atmospheric pressure at a level below the saturation temperature for that pressure. The heated liquid wastes are sprayed from a spray nozzle from the inside of an evaporator into the super-heated state and subjected to flash distillation. They are further heated to deposit and solidify the solidification components in the solidifying evaporation steams. The solidified powder is fallen downwardly and heated for removing water content. The recovered powder is vibrated so as not to be solidified and then reclaimed in a solidification storage vessel. Steams after flash distillation are separated into gas, liquid and solids by buffles. (Horiuchi, T.)

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

Waste management at the Karlsruhe Nuclear Research Center

International Nuclear Information System (INIS)

Hoehlein, G.; Lins, W.

1982-01-01

In the Karlsruhe Nuclear Research Center the responsibility for waste management is concentrated in the Decontamination Department which serves to collect and transport all liquid waste and solid material from central areas in the center for further waste treatment, clean radioactive equipment for repair and re-use or for recycling of material, remove from the liquid effluents any radioactive and chemical pollutants as specified in legislation on the protection of waters, convert radioactive wastes into mechanically and chemically stable forms allowing them to be transported into a repository. (orig./RW)

Treatability studies for decontamination of Melton Valley Storage Tank supernate

International Nuclear Information System (INIS)

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

1992-08-01

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

Method of vitrificating fine-containing liquid waste

International Nuclear Information System (INIS)

Hagiwara, Minoru; Matsunaka, Kazuhisa.

1989-01-01

This invention concerns a vitrificating method of liquid wastes containing fines (metal powder discharged upon cutting fuel cans) used in a process for treating high level radioactive liquid wastes or a process for treating liquid wastes from nuclear power plants. Liquid wastes containing fines, slurries, etc. are filtered by a filter vessel comprising glass fibers. The fines are supplied as they are to a glass melting furnace placed in the vessel. Filterates formed upon filteration are mixed with other high level radioactive wastes and supplied together with starting glass material to the glass melting furnace. Since the fine-containing liquid wastes are processed separately from high radioactive liquid wastes, clogging of pipeways, etc. can be avoided, supply to the melting furnace is facilitated and the operation efficiency of the vitrification process can be improved. (I.N.)

Method of processing radioactive liquid wastes

International Nuclear Information System (INIS)

Kurumada, Norimitsu; Shibata, Setsuo; Wakabayashi, Toshikatsu; Kuribayashi, Hiroshi.

1984-01-01

Purpose: To facilitate the procession of liquid wastes containing insoluble salts of boric acid and calcium in a process for solidifying under volume reduction of radioactive liquid wastes containing boron. Method: A soluble calcium compound (such as calcium hydroxide, calcium oxide and calcium nitrate) is added to liquid wastes whose pH value is adjusted neutral or alkaline such that the molar ratio of calcium to boron in the liquid wastes is at least 0.2. Then, they are agitated at a temperature between 40 - 70 0 C to form insoluble calcium salt containing boron. Thereafter, the liquid is maintained at a temperature less than the above-mentioned forming temperature to age the products and, thereafter, the liquid is evaporated to condensate into a liquid concentrate containing 30 - 80% by weight of solid components. The concentrated liquid is mixed with cement to solidify. (Ikeda, J.)

Options for the decontamination of alpha-bearing liquid wastes

International Nuclear Information System (INIS)

Carley-Macauly, K.W.; Gutman, R.G.; Hooper, E.W.; Logsdail, D.H.; Rees, J.H.; Simpson, M.P.; Smyth, M.J.; Turner, A.D.

1984-08-01

This document reviews the processes potentially available, and their state of development, for the removal of alpha activity from aqueous waste streams. In present practice, most such streams are treated by precipitation, usually with an iron hydroxide, but the potential role and limitations of other precipitants, of ion exchange techniques and solvent extraction are also discussed as well as newer electrochemical methods. Because of the importance of precipitation, and the fact the α-activity often occurs in suspended form in wastes, the methods for solids separation and concentration are considered in some detail, together with other physical processes such as evaporation. The equipment and operational aspects are also discussed, particularly for precipitation, ion exchange and solvent extraction treatments. The conclusions relate to an extensive table in which the different methods are compared. The optimum treatment or combination of treatments will depend on the waste stream and other circumstances (particularly on the chemical and radiological constituents of the waste, and its rate of arising) and the aim of this work is to give an initial guide to the choice among the options. (author)

Method of recovering phosphoric acid type decontaminating electrolytes by electrodeposition

International Nuclear Information System (INIS)

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

1985-01-01

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

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

Purification and solidification of reactor wastes at a Canadian nuclear generating station

International Nuclear Information System (INIS)

Buckley, L.P.; Burt, D.A.

1981-06-01

Chalk River Nuclear Laboratories are developing methods to condition power reactor wastes and to immobilize their radionuclides. Evaporation alone and combined with bituminization has been an important part of the program. After testing at the laboratories a 0.5 m 2 wiped-film evaporator was sent to the Douglas Point Nuclear Generating Station (220 MWe) to demonstrate its suitability to handle typical reactor liquid wastes. Two specific tasks undertaken with the wiped-film evaporator were successfully completed. The first was purification of contaminated heavy water which had leaked from the moderator circuit. The heavy water is normally recovered, cleaned by filters and ion-exchange resin and then upgraded by electrolysis. Cleaning the heavy water with the wiped-film evaporator produced better quality water for upgrading than had been achieved by any previous method and at much lower operating cost. The second task was to concentrate and immobilize a decontamination waste. The waste was generated from the decontamination of pump bowls used in the primary heat transport circuit. The simultaneous addition of the liquid waste and bitumen emulsion to the wiped-film evaporator produced a solid containing 30 wt% waste solids in a bitumen matrix. The volume reduction achieved was 16:1 based on the volumes of initial liquid waste and the final product generated. The quantity sent to storage was 20 times less than had the waste been immobilized in a cement matrix. The successful demonstration has resulted in a proposal to install a wiped-film evaporator at the station to clean heavy water and immobilize decontamination wastes. (author)

Liquid secondary waste. Waste form formulation and qualification

Energy Technology Data Exchange (ETDEWEB)

Cozzi, A. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Dixon, K. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hill, K. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); King, W. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nichols, R. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-03-01

The Hanford Site Effluent Treatment Facility (ETF) currently treats aqueous waste streams generated during Site cleanup activities. When the Hanford Tank Waste Treatment and Immobilization Plant (WTP) begins operations, a liquid secondary waste (LSW) stream from the WTP will need to be treated. The volume of effluent for treatment at the ETF will increase significantly. Washington River Protection Solutions is implementing a Secondary Liquid Waste Immobilization Technology Development Plan to address the technology needs for a waste form and solidification process to treat the increased volume of waste planned for disposal at the Integrated Disposal Facility IDF). Waste form testing to support this plan is composed of work in the near term to demonstrate the waste form will provide data as input to a performance assessment (PA) for Hanford’s IDF.

Radioactive liquid waste processing system

International Nuclear Information System (INIS)

Noda, Tetsuya; Kuramitsu, Kiminori; Ishii, Tomoharu.

1997-01-01

The present invention provides a system for processing radioactive liquid wastes containing laundry liquid wastes, shower drains or radioactive liquid wastes containing chemical oxygen demand (COD) ingredients and oil content generated from a nuclear power plant. Namely, a collecting tank collects radioactive liquid wastes. A filtering device is connected to the exit of the collective tank. A sump tank is connected to the exit of the filtering device. A powdery active carbon supplying device is connected to the collecting tank. A chemical fluid tank is connected to the collecting tank and the filtering device by way of chemical fluid injection lines. Backwarding pipelines connect a filtered water flowing exit of the filtering device and the collecting tank. The chemical solution is stored in the chemical solution tank. Then, radioactive materials in radioactive liquid wastes generated from a nuclear power plant are removed by the filtering device. The water quality standard specified in environmental influence reports can be satisfied. In the filtering device, when the filtering flow rate is reduced, the chemical fluid is supplied from the chemical fluid tank to the filtering device to recover the filtering flow rate. (I.S.)

Radioactive liquid waste processing method

International Nuclear Information System (INIS)

Yasumura, Keijiro; Yoshikawa, Jun; Noda, Tetsuya; Kobayashi, Fumio.

1995-01-01

Floor drainages are mixed with low electroconductive liquid wastes, and after filtering the mixed liquid wastes by a hollow thread membrane filters, they are subjected to a desalting treatment by a desalter. The mixing ratio of the floor drainages to the lower electroconductive liquid wastes is determined to not more than 50wt%. With such procedures, since ionic ingredients are further diluted by mixing the floor drainages to the low electroconductive liquid wastes, sufficient margin can be provided up to the saturation of the ion exchange resins of the desalter, to maintain the ion exchange performance for a long period of time. Further, the recovery of the amount of permeation water and a differential pressure of filtration upon back washing of the hollow thread membrane filters is facilitated, thereby enabling to perform regeneration easily at high efficiency. (T.M.)

Experimental and theoretical study of flowing foam and of the liquid film formed on the wall for the improvement of decontamination processes using foams

International Nuclear Information System (INIS)

Pouvreau, J.

2002-01-01

Amongst chemical decontamination techniques, the foam cleaning process has the advantage of reducing the amount of liquid used, thus limiting the quantity of the chemical reagents and the secondary waste volume. In order to improve this process, it is essential to understand the behaviour of the foam in the vicinity of the contaminated surface. Two methods of study have been initiated. Firstly, the characterization of the liquid film formed on the wall, and secondly, the characterization of the foam bed. Furthermore, our goal is to set up a drainage model which enables a choice of process parameters. Flush-mounted conductance probes have been developed in order to determine the thickness of the liquid film at the surface and the foam liquid fraction. The influence of the foam on the film structure and the interpretation of the thickness measured is discussed. The process studied consists of filling the facility with foam and letting the foam drain once the facility is full. It was demonstrated that the liquid film thickness varies between a few microns and 50 μm and that the value depends on position and time. Furthermore, a strong correlation links the film thickness and the foam liquid fraction. A drift-flux model has been built to describe the drainage of the upstream flow or static foam. The model is solved by using the method of characteristics. Analytical solutions are obtained and the liquid fraction evolution can easily be represented on a single diagram. The parameters of the void-drift closure law have been deducted from the experiments. The comparison to experimental data has shown that the model is well adapted. The laboratory therefore has experimental and theoretical equipment to study any foam. Finally, the model is applied to realistic decontamination configurations in order to present how determine the parameters of the process. (author) [fr

Use of laser ablation in nuclear decontamination

International Nuclear Information System (INIS)

Moggia, Fabrice; Lecardonnel, Xavier; Damerval, Frederique

2012-09-01

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

Treatment methods for radioactive mixed wastes in commercial low-level wastes - technical considerations

International Nuclear Information System (INIS)

MacKenzie, D.R.; Kempf, C.R.

1986-01-01

Treatment options for the management of three generic categories of radioactive mixed waste in commercial low-level wastes (LLW) have been identified and evaluated. These wastes were characterized as part of a BNL study in which LLW generators were surveyed for information on potential chemical hazards in their wastes. The general treatment options available for mixed wastes are destruction, immobilization, and reclamation. Solidification, absorption, incineration, acid digestion, wet-air oxidation, distillation, liquid-liquid solvent extraction, and specific chemical destruction techniques have been considered for organic liquid wastes. Containment, segregation, decontamination, and solidification or containment of residues, have been considered for lead metal wastes which have themselves been contaminated and are not used for purposes of waste disposal shielding, packaging, or containment. For chromium-containing wastes, solidification, incineration, wet-air oxidation, acid digestion, and containment have been considered. Fore each of these wastes, the management option evaluation has included an assessment of testing appropriate to determine the effect of the option on both the radiological and potential chemical hazards present

Radioactive waste management in West Germany

Energy Technology Data Exchange (ETDEWEB)

Krause, H [Kernforschungszentrum Karlsruhe G.m.b.H. (Germany, F.R.)

1978-01-01

The technologies developed in West Germany for radioactive waste management are widely reviewed. The first topic in this review paper is the disposal of low- and middle-level radioactive liquid wastes. Almost all these liquid wastes are evaporated, and the typical decontamination factor attained is 10/sup 4/ -- 10/sup 6/. The second topic is the solidification of residuals. Short explanation is given to bituminization and some new processes. The third topic is high-level liquid wastes. Degradation of glass quality due to various radiation is discussed. Embedding of small glass particles containing radioactive wastes into metal is also explained. Disposals of low-level solid wastes and the special wastes produced from reprocessing and mixed oxide fuel fabrication are explained. Final disposal of radioactive wastes in halite is discussed as the last topic. Many photographs are used to illustrate the industrial or experimental use of those management methods.

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

International Nuclear Information System (INIS)

Rousselle, Jerome

2004-01-01

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

The immobilization of organic liquid wastes

International Nuclear Information System (INIS)

Greenhalgh, W.O.

1986-01-01

This report describes a portland cement immobilization process for the disposal treatment of radioactive organic liquid wastes which would be generated in a FFTF fuels reprocessing line. An incineration system already on-hand was determined to be too costly to operate for the 100 to 400 gallons per year organic liquid. Organic test liquids were dispersed into an aqueous phosphate liquid using an emulsifier. A total of 109 gallons of potential and radioactive aqueous immiscible organic liquid wastes from Hanford 300 Area operations were solidified with portland cement and disposed of as solid waste during a 3 month test program with in-drum mixers. Waste packing efficiencies varied from 32 to 40% and included pump oils, mineral spirits, and TBP-NPH type solvents

Final treatment of liquid radioactive wastes

International Nuclear Information System (INIS)

Svolik, S.

2004-01-01

Final treatment of liquid radioactive wastes which are produced by 1 st and 2 nd bloc of the Mochovce NPP, prepares the NPP in its natural range. The purpose of the equipment is liquidation of wastes, which are formed at production. Wastes are warehoused in the building of active auxiliary plants in the present time, where are reservoirs in which they are deposited. Because they are already feeling and in 2006 year they should be filled definitely, it is necessary to treat them in that manner, so as they may be liquidated. Therefore the Board of directors of the Slovenske elektrarne has disposed about construction of final treatment of liquid radioactive wastes in the Mochovce NPP. Because of transport the wastes have to be treated in the locality of power plant. Technically, the final treatment of the wastes will be interconnected with building of active operation by bridges. These bridges will transport the wastes for treatment into processing centre

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

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

Characterization of the solid radioactive waste From Cernavoda NPP

International Nuclear Information System (INIS)

Iordache, M.; Laotaru, V.

2005-01-01

Full text: During the operation of a nuclear plant significant quantities of radioactive waste result that have a very large diversity. At Cernavoda NPP large amounts of wastes are either non-radioactive wastes or radioactive wastes, each of these being managed completely different from which other. For a CANDU type reactor, the appearance of radioactive wastes is due to contamination with the following types of radioactive substances: - fission products resulting from nuclear fuel burning; - activated products from materials composing the technological systems; - activated products in process fluids. Radioactive wastes can be in solid, liquid or gas form. At Cernavoda NPP the solid wastes represent about 70% of the waste volume which is produced during plant operation and as a consequence of maintenance and decontamination operations. The most important types of solid wastes that are obtained and then handled, processed (if necessary) and temporarily stored are: solid low-level radioactive wastes (classified as compactible and non-compactible), solid medium radioactive wastes, spent resins, used filters and filter cartridges. The liquid radioactive waste class includes organic liquids (used oil, scintillator liquids and used solvents) and aqueous wastes resulting from process system operating, from decontamination and maintenance operations. Radioactive gas wastes occur subsequently to the fission process inside the fuel elements as well as due to the neutron activation of process fluids in the reactor systems. As result of plant operation, iodine, noble gases, tritium and radioactive particles occur and are passed toward the ventilation stack in a controlled manner so that environmental release of radioactive materials with concentrations exceeding the maximum permissible level could not occur. (authors)

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

Main directions of works on radioactive waste management at 30-km zone near the Chernobyl' NPP

International Nuclear Information System (INIS)

Grushinskij, B.Ya.; Komarov, V.I.; Proskuryakov, A.N.; Kham'yanov, L.N.; Khubizov, S.B.; Ignatenko, E.I.; Ryzhkova, V.N.; Luppov, V.A.; Matskevich, G.V.; Frolov, V.N.

1989-01-01

Main points and stages of creating an specialized enterprise for centralized reprocessing and radioactive waste disposal are considered. The enterprise is intended for collection conditioning and burial of all types of radioactive wastes, formed during liquidation of accident effect at the Chernobyl' NPP as well as forming in operation of NPP. The enterprise is also used to decontaminate equipment and constructions, for reprocessing of secondary radioactive wastes forming during decontamination process of equipment constructions, transport and work clothes

Decontamination of evaporator concentrated for cesium, strontium and transuranium elements

International Nuclear Information System (INIS)

Dozol, J.F.; Eymard, S.; Gambade, R.; La Rosa, G.; Casas i Garcia, J.

1992-01-01

Reprocessing produces medium activity liquid wastes. These wastes are evaporated, the distillate is discharged into the environment and all active and inactive salts are concentrated, leading to an important volume of wastes. The objective of this work is to separate long-lived radionuclides into a small volume addressed to a geological formation from the large volume of the concentrate, this concentrate after embedding is disposed on surface site. Supported liquid membranes (S.L.M.s) are used because they enable us to use low inventory of organic phase, hence to use very sophisticated and expensive extractants. To confirm the results obtained with simulated wastes, tests were carried out with genuine concentrate using two S.L.M.s: the first one with CMPO/TBP diluted in decalin, the second one impregnated by the mixture DC18-C-6/decanol/hexylbenzene. The decontamination factor (DF) achieved for actinides is about 100 with the CMPO/TBP SLM. The DF is increased by the second membrane: after treatment with crown ether SLM, the total DF is higher than 400

Waste characterization for radioactive liquid waste evaporators at Argonne National Laboratory - West

International Nuclear Information System (INIS)

Christensen, B. D.

1999-01-01

Several facilities at Argonne National Laboratory - West (ANL-W) generate many thousand gallons of radioactive liquid waste per year. These waste streams are sent to the AFL-W Radioactive Liquid Waste Treatment Facility (RLWTF) where they are processed through hot air evaporators. These evaporators remove the liquid portion of the waste and leave a relatively small volume of solids in a shielded container. The ANL-W sampling, characterization and tracking programs ensure that these solids ultimately meet the disposal requirements of a low-level radioactive waste landfill. One set of evaporators will process an average 25,000 gallons of radioactive liquid waste, provide shielding, and reduce it to a volume of six cubic meters (container volume) for disposal. Waste characterization of the shielded evaporators poses some challenges. The process of evaporating the liquid and reducing the volume of waste increases the concentrations of RCIU regulated metals and radionuclides in the final waste form. Also, once the liquid waste has been processed through the evaporators it is not possible to obtain sample material for characterization. The process for tracking and assessing the final radioactive waste concentrations is described in this paper, The structural components of the evaporator are an approved and integral part of the final waste stream and they are included in the final waste characterization

Minimization of waste volumes by means of pin-pointed decontamination during decommissioning measures. Final report

International Nuclear Information System (INIS)

Henschel, K.; Jacobs, W.; Kanitz, L.; Schildbach, T.

1992-06-01

This semi-automated equipment is able to remove surface building contamination as well as take radioactive measurements. This equipment is newly developed. The goal of the equipment is to improve the identification of areas of contamination and the compounding decontamination of epoxy layer building construction material by using commercially available components minimizing the waste volume. A system design for decommissioning of building surfaces was developed, selected components were tested and their function certified. With this systems concept the decontamination of fixed epoxy layers up to 20 m in height is possible. Operational data for the system are available. (orig.) [de

Decontamination of stainless steel canisters that contain high-level waste

International Nuclear Information System (INIS)

Bray, L.A.

1987-01-01

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

Subject bibliography of radioactive waste management publications at Pacific Northwest Laboratory, 1975-1978

International Nuclear Information System (INIS)

Powell, J.A.

1981-10-01

This bibliography contains publications from 1975 to 1978 written by PNL staff. PNL translations are also announced in this document. The following areas are covered: actinides; airborne wastes; alternative waste forms; calcination; characterization; containers; decontamination; disposal; high-level wastes; liquid wastes; radionuclide migration; safety; separation processes; soils; solidification; storage; transport; transuranic waste; and vitrification

Decontamination impacts on solidification

International Nuclear Information System (INIS)

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

1985-01-01

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

Liquid and Gaseous Waste Operations Department annual operating report, CY 1992

Energy Technology Data Exchange (ETDEWEB)

Gillespie, M.A.; Maddox, J.J.; Scott, C.B.

1993-03-01

A total of 6.05 x 10{sup 7} gal of liquid waste was decontaminated by the Process Waste Treatment Plant (PWTP) ion exchange system during CY 1992. This averaged to 115 gpm throughout the year. When necessary, a wastewater sidestream of 50--80 gpm was treated through the use of a natural zeolite treatment system. An additional 8.00 x 10{sup 6} gal (average of 15 gpm throughout the year) were treated by the zeolite system. Therefore, the average total flow treated at the PWTP for CY 1992 was 130 gpm. In mid-June, the zeolite system was repiped to allow it the capability to treat the ion exchange system`s discharge due to rising Cs problems in the wastewater. While being used to treat the ion exchange system`s discharge, it cannot treat a sidestream of wastewater. During the year, the regeneration of the cation exchange resins resulted in the generation of 7.83 x 10{sup 3} gal of liquid low-level waste (LLLW) concentrate and 1.15 x 10{sup 4} gal of LLLW evaporator feed. The head-end softening process (precipitation/clarification) generated 604 drums (4.40 x 10{sup 3} ft{sup 3}) of solid low-level waste sludge. The zeolite treatment system generated approximately 8.40 x 10{sup 2} ft{sup 3} of spent zeolite resin, which was turned over to the Solid Waste Operations Department for disposal. See Table 1 for a monthly summary of activities at the PWTP. Figures 1, 2, 3, and 4 show a comparison of operations at the PWTP in 1992 with previous years. Figure 5 shows a comparison of annual rainfall at Oak Ridge National Laboratory (ORNL) since 1987. A total of 1.55 x 10{sup 8} gal of liquid waste (average of 294 gpm throughout the year) was treated at the Nonradiological Wastewater Treatment Plant (NRWTP). Of this amount, 1.40 x 10{sup 7} gal were treated by the precipitation/clarification process for removal of heavy metals. Twenty-five boxes (1.60 x 10{sup 3} ft{sup 3}) of solid sludge generated by the precipitation/clarification process were removed from the filter press room.

Liquid and Gaseous Waste Operations Department annual operating report, CY 1992

Energy Technology Data Exchange (ETDEWEB)

Gillespie, M.A.; Maddox, J.J.; Scott, C.B.

1993-03-01

A total of 6.05 x 10[sup 7] gal of liquid waste was decontaminated by the Process Waste Treatment Plant (PWTP) ion exchange system during CY 1992. This averaged to 115 gpm throughout the year. When necessary, a wastewater sidestream of 50--80 gpm was treated through the use of a natural zeolite treatment system. An additional 8.00 x 10[sup 6] gal (average of 15 gpm throughout the year) were treated by the zeolite system. Therefore, the average total flow treated at the PWTP for CY 1992 was 130 gpm. In mid-June, the zeolite system was repiped to allow it the capability to treat the ion exchange system's discharge due to rising Cs problems in the wastewater. While being used to treat the ion exchange system's discharge, it cannot treat a sidestream of wastewater. During the year, the regeneration of the cation exchange resins resulted in the generation of 7.83 x 10[sup 3] gal of liquid low-level waste (LLLW) concentrate and 1.15 x 10[sup 4] gal of LLLW evaporator feed. The head-end softening process (precipitation/clarification) generated 604 drums (4.40 x 10[sup 3] ft[sup 3]) of solid low-level waste sludge. The zeolite treatment system generated approximately 8.40 x 10[sup 2] ft[sup 3] of spent zeolite resin, which was turned over to the Solid Waste Operations Department for disposal. See Table 1 for a monthly summary of activities at the PWTP. Figures 1, 2, 3, and 4 show a comparison of operations at the PWTP in 1992 with previous years. Figure 5 shows a comparison of annual rainfall at Oak Ridge National Laboratory (ORNL) since 1987. A total of 1.55 x 10[sup 8] gal of liquid waste (average of 294 gpm throughout the year) was treated at the Nonradiological Wastewater Treatment Plant (NRWTP). Of this amount, 1.40 x 10[sup 7] gal were treated by the precipitation/clarification process for removal of heavy metals. Twenty-five boxes (1.60 x 10[sup 3] ft[sup 3]) of solid sludge generated by the precipitation/clarification process were removed from the filter

Liquid and Gaseous Waste Operations Department annual operating report, CY 1992

International Nuclear Information System (INIS)

Gillespie, M.A.; Maddox, J.J.; Scott, C.B.

1993-03-01

A total of 6.05 x 10 7 gal of liquid waste was decontaminated by the Process Waste Treatment Plant (PWTP) ion exchange system during CY 1992. This averaged to 115 gpm throughout the year. When necessary, a wastewater sidestream of 50--80 gpm was treated through the use of a natural zeolite treatment system. An additional 8.00 x 10 6 gal (average of 15 gpm throughout the year) were treated by the zeolite system. Therefore, the average total flow treated at the PWTP for CY 1992 was 130 gpm. In mid-June, the zeolite system was repiped to allow it the capability to treat the ion exchange system's discharge due to rising Cs problems in the wastewater. While being used to treat the ion exchange system's discharge, it cannot treat a sidestream of wastewater. During the year, the regeneration of the cation exchange resins resulted in the generation of 7.83 x 10 3 gal of liquid low-level waste (LLLW) concentrate and 1.15 x 10 4 gal of LLLW evaporator feed. The head-end softening process (precipitation/clarification) generated 604 drums (4.40 x 10 3 ft 3 ) of solid low-level waste sludge. The zeolite treatment system generated approximately 8.40 x 10 2 ft 3 of spent zeolite resin, which was turned over to the Solid Waste Operations Department for disposal. See Table 1 for a monthly summary of activities at the PWTP. Figures 1, 2, 3, and 4 show a comparison of operations at the PWTP in 1992 with previous years. Figure 5 shows a comparison of annual rainfall at Oak Ridge National Laboratory (ORNL) since 1987. A total of 1.55 x 10 8 gal of liquid waste (average of 294 gpm throughout the year) was treated at the Nonradiological Wastewater Treatment Plant (NRWTP). Of this amount, 1.40 x 10 7 gal were treated by the precipitation/clarification process for removal of heavy metals. Twenty-five boxes (1.60 x 10 3 ft 3 ) of solid sludge generated by the precipitation/clarification process were removed from the filter press room

Method of processing radioactive liquid wastes

Energy Technology Data Exchange (ETDEWEB)

Sugimoto, Y; Kikuchi, M; Funabashi, K; Yusa, H; Horiuchi, S

1978-12-21

Purpose: To decrease the volume of radioactive liquid wastes essentially consisting of sodium hydroxide and boric acid. Method: The concentration ratio of sodium hydroxide to boric acid by weight in radioactive liquid wastes essentially consisting of sodium hydroxide and boric acid is adjusted in the range of 0.28 - 0.4 by means of a pH detector and a sodium concentration detector. Thereafter, the radioactive liquid wastes are dried into powder and then discharged.

Initial decontamination of the equipment decontamination room at the West Valley Demonstration Project. Topical report, September 1983-May 1985

International Nuclear Information System (INIS)

Meigs, R.A.

1985-12-01

The purpose of this report is to document the initial decontamination of the Equipment Decontamination Room (EDR). The effort spanned a two-year period and included packaging and removal of waste; grinding away contaminated concrete floors; pump-out and spraydown of an equipment soaking pit; washing and painting of walls, equipment, and floors; refurbishment of utilities and various pieces of equipment; and load tests of EDR and Chemical Process Cell (CPC) cranes. After decontamination, the EDR was converted into a waste handling area for the decommissioning of the CPC

The selective removal of 90Sr and 137Cs from liquid low-level waste at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Bostick, D.T.; Arnold, W.D.; Burgess, M.W.; Taylor, P.A.; Kent, T.E.

1995-01-01

Methods are being developed for the selective removal of the two principal radioactive contaminants, 90 Sr and 137 Cs, from liquid low-level waste generated and/or stored at Oak Ridge National Laboratory. These methods are to be used in a future centralized treatment facility at ORNL. Removal of 90 Sr in the proposed treatment flashed is based on coprecipitation from strongly alkaline waste by adding stable strontium to the waste solution. Ferric sulfate, added with the stable strontium, improves the 90 Sr removal and aids in the flocculation of the strontium carbonate (SrCO 3 ) precipitate. After separation of the solids, the resultant supernate is adjusted to pH 8 for the cesium removal treatment. Upon pH adjustment, aluminum originally present in the untreated alkaline waste precipitates and sorbs an additional amount of 90 Sr. Cesium is removed from the neutralized waste by two sequential treatments with potassium cobalt hexacyanoferrate (KCCF) slurry formed by the addition of potassium ferrocyanide (K 4 Fe(CN) 6 ) and cobalt nitrate (Co(NO 3 ) 2 ) solutions. The cumulative decontamination factors (DFs) for 90 Sr and 137 Cs in benchscale studies are 4900 and 1 x 10 6 , respectively, if high speed centrifugation is used for the liquid/solid separations. Efforts are now underway to evaluate process-scale techniques to perform the liquid/solid separations required for removal of SrCO 3 and 137 Cs-bearing hexacyanoferrate solids from the treated waste solution

Decontamination for free release

Energy Technology Data Exchange (ETDEWEB)

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

1997-02-01

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

Sulphate in Liquid Nuclear Waste: from Production to Containment

Energy Technology Data Exchange (ETDEWEB)

Lenoir, M.; Grandjean, A.; Ledieu, A.; Dussossoy, J.L.; Cau Dit Coumes, C.; Barre, Y.; Tronche, E. [CEA Marcoule, DEN/DTCD/SECM/LDMC, Batiment 208 BP17171, Bagnols sur Ceze, 30207 (France)

2009-06-15

Nuclear industry produces a wide range of low and intermediate level liquid radioactive wastes which can include different radionuclides such as {sup 90}Sr. In La Hague reprocessing plant and in the nuclear research centers of CEA (Commissariat a l'Energie Atomique), the coprecipitation of strontium with barium sulphate is the technique used to treat selectively these contaminated streams with the best efficiency. After the decontamination process, low and intermediate level activity wastes incorporating significant quantities of sulphate are obtained. The challenge is to find a matrix easy to form and with a good chemical durability which is able to confine this kind of nuclear waste. The current process used to contain sulphate-rich nuclear wastes is bituminization. However, in order to improve properties of containment matrices and simplify the process, CEA has chosen to supervise researches on other materials such as cements or glasses. Indeed, cements are widely used for the immobilization of a variety of wastes (low and intermediate level wastes) and they may be an alternative matrix to bitumen. Even if Portland cement, which is extensively used in the nuclear industry, presents some disadvantages for the containment of sulphate-rich nuclear wastes (risk of swelling and cracking due to delayed ettringite formation), other cement systems, such as calcium sulfo-aluminate binders, may be valuable candidates. Another matrix to confine sulphate-rich waste could be the glass. One of the advantages of this material is that it could also immobilize sulphate containing high level nuclear waste which is present in some countries. This waste comes from the use of ferrous sulfamate as a reducing agent for the conversion of Pu{sup 4+} to Pu{sup 3+} in the partitioning stage of the actinides during reprocessing. Sulphate solubility in borosilicate glasses has already been studied in CEA at laboratory and pilot scales. At a pilot scale, low level liquid waste has been

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

New decontamination techniques: chemical gels, electropolishing and abrasives

International Nuclear Information System (INIS)

Brunel, G.; Gauchon, J.P.; Kervegant, Y.; Josso, F.

1991-01-01

The decommissioning of nuclear installations requires decontamination techniques that are efficient, simple to apply and producing a small amount of wastes, which are easy to process. With a view to this, three decontamination methods, which appear to be particularly suited to decommissioning, have been studied. These three methods are: - spraying of gels carrying chemical decontaminating agents, - electropolishing with a swab device, - abrasives blasting. After parametric tests on non-radioactive and active samples, the industrial application of these methods in the dismantling of installations was studied. These industrial applications concern: - decontamination of pieces coming from the German BWR ISAR by immersion and gel spraying, - decontamination, mainly by gel spraying, and dismantling of the BRENNILIS bituminisation plant, - decontamination of part of the cooling circuit of the graphite gas reactor G2 by gel spraying, - decontamination of a component of the FBR SuperPhenix, using dry abrasives blasting. During the first three applications, generated secondary wastes volume and form were determined. 33 tabs., 16 figs., 12 refs

Treatment methods for radioactive mixed wastes in commercial low-level wastes: technical considerations

International Nuclear Information System (INIS)

MacKenzie, D.R.; Kempf, C.R.

1986-01-01

Treatment options for the management of three generic categories of radioactive mixed waste in commercial low-level wastes (LLW) have been identified and evaluated. These wastes were characterized as part of a BNL study in which LLW generators were surveyed for information on potential chemical hazards in their wastes. The general treatment options available for mixed wastes are destruction, immobilization, and reclamation. Solidification, absorption, incineration, acid digestion, wet-air oxidation, distillation, liquid-liquid wastes. Containment, segregation, decontamination, and solidification or containment of residues, have been considered for lead metal wastes which have themselves been contaminated and are not used for purposes of waste disposal shielding, packaging, or containment. For chromium-containing wastes, solidification, incineration, wet-air oxidation, acid digestion, and containment have been considered. For each of these wastes, the management option evaluation has included an assessment of testing appropriate to determine the effect of the option on both the radiological and potential chemical hazards present

Treatment methods for radioactive mixed wastes in commercial low-level wastes: technical considerations

Energy Technology Data Exchange (ETDEWEB)

MacKenzie, D.R.; Kempf, C.R.

1986-01-01

Treatment options for the management of three generic categories of radioactive mixed waste in commercial low-level wastes (LLW) have been identified and evaluated. These wastes were characterized as part of a BNL study in which LLW generators were surveyed for information on potential chemical hazards in their wastes. The general treatment options available for mixed wastes are destruction, immobilization, and reclamation. Solidification, absorption, incineration, acid digestion, wet-air oxidation, distillation, liquid-liquid wastes. Containment, segregation, decontamination, and solidification or containment of residues, have been considered for lead metal wastes which have themselves been contaminated and are not used for purposes of waste disposal shielding, packaging, or containment. For chromium-containing wastes, solidification, incineration, wet-air oxidation, acid digestion, and containment have been considered. For each of these wastes, the management option evaluation has included an assessment of testing appropriate to determine the effect of the option on both the radiological and potential chemical hazards present.

Characterisation of radioactive waste at Cernavoda NPP Unit 1 during normal operation

International Nuclear Information System (INIS)

Iordache, M.; Bujoreanu, L.; Popescu, I. V.

2008-01-01

During the operation of a nuclear plant significant quantities of radioactive waste results that have a very large diversity. At Cernavoda NPP the important waste categories are non-radioactive wastes and radioactive wastes, which are manipulated completely different from which other. For a CANDU type reactor, the production of radioactive wastes is due to contamination with the following types of radioactive substances: - fission products resulting from nuclear fuel burning; - activated products of materials which form part of the technological systems; - activated products of process fluids. Radioactive wastes can be in solid, liquid or gas form. At Cernavoda NPP the solid wastes represent about 70% of the waste volume which is produced during plant operation and as a consequence of maintenance and decontamination activities. The most important types of solid wastes that are obtained and then handled, processed (if required) and temporarily stored are: solid low level radioactive wastes (classified as compact and non-compact), solid medium radioactive wastes, spent resins, used filters and filter cartridges. The liquid radioactive waste class includes organic liquids (used oil, scintillator liquids and used solvents) and aqueous wastes resulting from process system operating, decontamination and maintenance operations. Radioactive gas wastes occur subsequent to the fission process inside the fuel elements as well as due to the process fluids neutron activation in the reactor systems. As result of the plant operation, iodine, noble gases, tritium and radioactive particles occur and are passed to the ventilation stack in a controlled manner so that an exceeding of the maximum permissible concentrations of radioactive material to the environment should not occur. (authors)