Investigation of Radionuclide Sorption on Peat

2012 ◽  
Vol 51 (4) ◽  
pp. 342-346
Author(s):  
A. Abramenkovs ◽  
M. Klavins ◽  
J. Rudzitis ◽  
A. Popelis
Keyword(s):  
Radioactive Waste ◽  
Research Reactor ◽  
Natural Radionuclides ◽  
Waste Waters ◽  
Emission Process ◽  
Radionuclide Sorption ◽  
Low Emission ◽  
Radioactive Water ◽  
Radionuclide Composition ◽  
Technical Considerations

Organic sorbents like peat can be successfully used for the purification of radioactive waste waters and are favoured by economical and technical considerations. The peat filters are also friendlier to the environment, since the manufacturing of such filters is a low emission process. This study examined the sorption of radionuclides 137Cs, 55Fe, 63Ni and 14C on peat samples. The initial radioactivity of the peat samples was studied before the experiments. Peat samples were taken from different bogs. Radionuclide solutions were prepared using deionised water and appropriate radionuclide composition from the Salaspils research reactor stock water. It was found that in all cases of peat samples, the main natural radionuclides were 210Pb, 40K and 214Bi. The artificial radionuclides 152Eu, 137Cs and 60Co were also found in the peat samples. Radionuclide sorption studies indicated that the initial radioactivity of the solution decreased in the case of radionuclides 63Ni, 14C, 55Fe and 137Cs. This confirmed that peat samples can effectively remove the radionuclides from radioactive water solutions.

scholarly journals Decommissioning of the ASTRA research reactor: Dismantling of the biological shield

2006 ◽  
Vol 21 (2) ◽  
pp. 79-91 ◽  
Author(s):  
Franz Meyer ◽  
Ferdinand Steger
Keyword(s):  
Radioactive Waste ◽  
Research Reactor ◽  
Activity Concentration ◽  
Research Center

The paper describes the dismantling of the inactive and activated areas of the biological shield of the ASTRA research reactor at the Austrian Research Center in Seibersdorf. The calculation of the parameters determining the activated areas at the shield (reference nuclide, nuclide vector in the barite concrete and horizontal and vertical reduction behaviors of activity concentration) and the activation profiles within the biological shield for unrestricted release, release restricted to permanent deposit and radioactive waste are presented. Considerations of located activation anomalies in the shield, e.g. in the vicinities of the beam-tubes, were made according to the reactor's operational history. Finally, an overview of the materials removed from the biological shield is given.

Disposal in the deep sea: analogue of nature or faux ami?

2003 ◽  
Vol 30 (1) ◽  
pp. 26-39 ◽  
Author(s):  
Paul A. Tyler
Keyword(s):  
Carbon Dioxide ◽  
Radioactive Waste ◽  
Deep Sea ◽  
Hydrothermal Vents ◽  
Natural Radionuclides ◽  
Deep Ocean ◽  
Turbidity Currents ◽  
Chemical Contamination ◽  
Seabed Sediment ◽  
Dredge Spoil

The deep sea is the world's largest ecosystem by volume and is assumed to have a high assimilative capacity. Natural events, such as the sinking of surface plant and animal material to the seabed, sediment slides, benthic storms and hydrothermal vents can contribute vast amounts of material, both organic and inorganic, to the deep ocean. In the past the deep sea has been used as a repository for sewage, dredge spoil and radioactive waste. In addition, there has been interest in the disposal of large man-made objects and, more recently, the disposal of industrially-produced carbon dioxide. Some of the materials disposed of in the deep sea may have natural analogues. This review examines natural processes in the deep sea including the vertical flux of organic material, turbidity currents and benthic storms, natural gas emissions, hydrothermal vents, natural radionuclides and rocky substrata, and compares them with anthropogenic input including sewage disposal, dredge spoil, carbon dioxide disposal, chemical contamination and the disposal of radioactive waste, wrecks and rigs. The comparison shows what are true analogues and what are false friends. Knowledge of the deep sea is fragmentary and much more needs to be known about this large, biologically-diverse system before any further consideration is given to its use in the disposal of waste.

Optimization Features in Management of Salaspils Research Reactor Decommissioning Waste

2003 ◽  
Author(s):  
A. Dreimanis
Keyword(s):  
Radioactive Waste ◽  
Waste Management ◽  
Research Reactor ◽  
Optimal Solution ◽  
Environmental Safety ◽  
Radioactive Waste Disposal ◽  
Disposal Site ◽  
Radioactive Waste Management ◽  
Safety Control ◽  
Simplified Approach

Management of decommissioning waste is considered as complex task of seeking for optimal solution in the environment of various competing technical, safety and socio-economical factors. If from the formal mathematics viewpoint it is a multi-parameter optimization task, then for real conditions simplified approach for such problem should be applied. We propose to decompose this task into the set of optimization analysis for particular steps, and then in each step it is easier to find optimum. For the real case of management of radioactive waste arising from dismantling and decommissioning of Salaspils Research Reactor (SRR) we consider following main optimization steps: 1) the choice of the decommissioning concept — among three elaborated versions — with estimation of the foreseen radioactive waste amount for disposal, recycling and free release, taking into account also potential exposures and financial resources; 2) establishment of national radioactive waste management agency “RAPA” Ltd., ensuring common administration and maintenance of the shutdown SRR and radioactive waste (RW) disposal site — RAPA manages some decommissioning activities of SRR and shall actively participate together with envisaged decommissioning operator in this process also in future, but in all stages will keep full responsibility of waste management; 3) optimization of radioactive waste transportation: i) organizational aspects (packing, transportation time, schedule, route, etc.), ii) environmental safety control; 4) optimization arrangement of space for radioactive waste disposal: i) choice of the best strategy to ensure a new space, ii) optimization of the vault size — to be able accommodate decommissioning waste without being oversized; 5) strategy of treatment, conditioning and packing of solid decommissioning waste; 6) optimization of liquid decommissioning waste management — its conditioning together with the solid radioactive waste; 7) socio-economical optimization features: i) existing infrastructure for RW disposal, ii) financial compensation for local municipality, iii) international cooperation, technical and financial assistance by EU, IAEA, Sweden. The proposed optimization features used in the developing of Concept for radioactive waste management in Latvia for the period 2003–2010 (which corresponds to the approved decommissioning period of SRR) supplement existing separate optimization aspects of decommissioning waste management and could be considered as simplified integral set of factors for elaboration of optimal strategy for decommissioning waste management.

Removal of silver and antimony radionuclides from low-level liquid radioactive waste of a research reactor through different scavenging precipitations

2004 ◽  
Vol 92 (7) ◽  
Author(s):  
F. Jan ◽  
M. Aslam ◽  
S. D. Orfi ◽  
A. Wahid
Keyword(s):  
Radioactive Waste ◽  
Research Reactor ◽  
Liquid Radioactive Waste ◽  
Liquid Waste ◽  
Low Level ◽  
Radioactivity Content

SummaryAfter upgrading the Pakistan Research Reactor-1, the amount of liquid waste and its increased radioactivity content necessitated a pre-disposal treatment to bring the activity down to disposal limits. Amongst several radionuclides in the waste,

Utilization of coal fly ash in solidification of liquid radioactive waste from research reactor

2014 ◽  
Vol 32 (5) ◽  
pp. 366-370 ◽  
Author(s):  
Ahmet Erdal Osmanlioglu
Keyword(s):  
Fly Ash ◽  
Radioactive Waste ◽  
Research Reactor ◽  
Coal Fly Ash ◽  
Solidification Process ◽  
Nuclear Industry ◽  
Radioactive Isotopes ◽  
Environmental Implications ◽  
Near Surface ◽  
Waste Sludge

In this study, the potential utilization of fly ash was investigated as an additive in solidification process of radioactive waste sludge from research reactor. Coal formations include various percentages of natural radioactive elements; therefore, coal fly ash includes various levels of radioactivity. For this reason, fly ashes have to be evaluated for potential environmental implications in case of further usage in any construction material. But for use in solidification of radioactive sludge, the radiological effects of fly ash are in the range of radioactive waste management limits. The results show that fly ash has a strong fixing capacity for radioactive isotopes. Specimens with addition of 5–15% fly ash to concrete was observed to be sufficient to achieve the target compressive strength of 20 MPa required for near-surface disposal. An optimum mixture comprising 15% fly ash, 35% cement, and 50% radioactive waste sludge could provide the solidification required for long-term storage and disposal. The codisposal of radioactive fly ash with radioactive sludge by solidification decreases the usage of cement in solidification process. By this method, radioactive fly ash can become a valuable additive instead of industrial waste. This study supports the utilization of fly ash in industry and the solidification of radioactive waste in the nuclear industry.

Decommissioning Activities for Salaspils Research Reactor

2011 ◽  
Author(s):  
A. Abramenkovs ◽  
J. Malnacs
Keyword(s):  
Radioactive Waste ◽  
Research Reactor ◽  
Legal Aspects ◽  
Radioactive Wastes ◽  
Measurement Equipment ◽  
Radiation Measurement ◽  
Spent Fuel ◽  
Nuclear Facility ◽  
Radioactive Materials ◽  
Conceptual Study

In May 1995, the Latvian government decided to shut down the Salaspils Research Reactor (SRR). The reactor is out of operation since July 1998. A conceptual study for the decommissioning of SRR has been carried out by Noell-KRC-Energie- und Umwelttechnik GmbH at 1998–1999. The Latvian government decided to start the direct dismantling to “green field” in October 26, 1999. The upgrade of decommissioning and dismantling plan was performed in 2003–2004 years, which change the main goal of decommissioning to the “brown field”. The paper deals with the SRR decommissioning experience during 1999–2010. The main decommissioning stages are discussed including spent fuel and radioactive wastes management. The legal aspects and procedures for decommissioning of SRR are described in the paper. It was found, that the involvement of stakeholders at the early stages significantly promotes the decommissioning of nuclear facility. Radioactive waste management’s main efforts were devoted to collecting and conditioning of “historical” radioactive wastes from different storages outside and inside of reactor hall. All radioactive materials (more than 96 tons) were conditioned in concrete containers for disposal in the radioactive wastes repository “Radons” at Baldone site. The dismantling of contaminated and activated components of SRR systems is discussed in paper. The cementation of dismantled radioactive wastes in concrete containers is discussed. Infrastructure of SRR, including personal protective and radiation measurement equipment, for decommissioning purposes was upgraded significantly. Additional attention was devoted to the free release measurement’s technique. The certified laboratory was installed for supporting of all decommissioning activities. All non-radioactive equipments and materials outside of reactor buildings were released for clearance and dismantled for reusing or conventional disposing. Weakly contaminated materials from reactor hall were collected, decontaminated and removed for clearance measurements.

The Removal, Transportation and Final Treatment and Conditioning of the THETIS Research Reactor Spent Fuel of the University of Ghent (Belgium) Achieved in 2010

2011 ◽  
Author(s):  
Hubert Thierens ◽  
Myriam Monsieurs ◽  
Vincent De pooter ◽  
Luc Noynaert ◽  
Patrick Maris ◽  
...  
Keyword(s):  
Radioactive Waste ◽  
Research Reactor ◽  
Storage Period ◽  
Disposal Site ◽  
Research Centre ◽  
Nuclear Materials ◽  
Spent Fuel ◽  
Nuclear Facilities ◽  
Enriched Uranium ◽  
Intermediate Storage

The THETIS research reactor on the site of the Nuclear Sciences Institute of the Ghent University has been in operation from 1967 until December 2003. This light-water moderated graphite-reflected low-enriched uranium pool-type reactor has been used for various purposes e.g. the production of radio-isotopes and activation analyses. During the first years its core power was 15 kW. In the early ’70, a core enlargement allowed for operation at typically 150 kW, while the maximum was allowed to be 250 kW. The fuel was 5% enriched uranium cladded with AISI304L stainless steel, with graphite plugs at both ends of the tubes. In order to decommission the reactor, the spent fuel and other nuclear materials present had to be removed from the reactor site. Ghent University entrusted SCK·CEN, the Belgian Nuclear Research Centre, with the study of the further management of the spent fuel. Various options such as reprocessing, intermediate storage awaiting final disposal were investigated. However the characteristics and the small amount of spent fuel (84.64 kg of UO2) made these solutions very expensive. In the meantime ONDRAF/NIRAS, the Belgian radioactive waste management agency, was developing together with Belgoprocess, a solution for final conditioning in 400 liter drums and further intermediate storage of the spent fuel in its nuclear facilities at the BELGOPROCESS site in Dessel. This conditioned waste is foreseen to enter the future geological disposal site after the intermediate storage period only after 2050. Finally SCK·CEN recommended this solution for the back-end of the THETIS spent fuel and Ghent University declared this spent fuel as radioactive waste. Once the feasibility for conditioning and storage was demonstrated, further actions were taken in order to unload the spent fuel out of the reactor and to transport it to the PAMELA-installation at the Belgoprocess site in Dessel. Finally after receiving all necessary licensing authorisations from the FANC/AFCN, the Belgian nuclear safety authority, the operations started at the reactor site beginning of 2010 and the spent fuel was placed into the intermediate storage building after conditioning at the Belgoprocess site at the end of 2010. The paper will focus on: - the inventarisation and characterization of the spent fuel and other nuclear materials; - the operations at Ghent University and Belgoprocess sites; - the conclusions drawn from the operations.

scholarly journals Radioecological analysis of the area of the storage of radioactive waste

10.12737/2156 ◽  
2013 ◽  
Vol 2 (6) ◽  
pp. 14-19 ◽  
Author(s):  
Лаврентьева ◽  
G. Lavrenteva
Keyword(s):  
Radioactive Waste ◽  
Total Dose ◽  
Main Part ◽  
Natural Radionuclides ◽  
Absorbed Dose ◽  
Radioactive Pollution ◽  
Geochemical Barrier ◽  
External Radiation ◽  
Term Data

A complex radioecological research was carried out at the site of the storage of radioactive waste. The analysis of long-term data on the 90Sr content in soil of the studied site allowed us to assume that the formation of natural geochemical barrier is possible. The area of radioactive pollution of the territory is determined. The assessment of a contribution of technogenic and natural radionuclides in total dose loading shows that the main part in the absorbed dose for mollusks was made by the external radiation formed 90Sr.

scholarly journals Risks assessment for the retrieval of radioactive waste from the old Russian cemetery Al -Tuwaitha site

2019 ◽  
Vol 13 (28) ◽  
pp. 155-161
Author(s):  
Asia H. Al-Mashhadani
Keyword(s):  
Radioactive Waste ◽  
Effective Dose ◽  
Natural Radionuclides ◽  
Radioactive Wastes ◽  
Retrieval Process ◽  
Low Level ◽  
Old Russian ◽  
Absorbed Doses ◽  
Risks Assessment ◽  
Committed Effective Dose

In this work the radioactive wastes in the Old RussianCemetery Al -Tuwaitha site were classified according to risks forworkers who are involved in the retrieval process. The exposureassessment results expressed as estimates of radionuclide intakes byinhalation and ingestion, exposure rates and duration for externalexposure pathways, and committed effective dose equivalents toindividuals from all relevant radionuclides and pathways. Resultsshowed the presence of natural radionuclides Ra-226, Th-234 and K-40, as well as the produced radionuclide Cs-137 and Eu-152 in thecemetery wells. The absorbed doses from the waste were classified totwo categories; exempt waste and low level waste according toabsorbed dose value. This studied site does not pose a radiologicalhazard for the workers.

Novovoronezh NPP Experience in Applying the Methodology for Measurement the Activity, Radionuclide Composition of Radioactive Waste in the NZK type Containers Using the «Satellite» Software

ANRI ◽  
2021 ◽  
Vol 0 (3) ◽  
pp. 36-47
Author(s):  
Vladimir Povarov ◽  
Andrey Merem'yanin ◽  
Nickolay Stepin ◽  
Sergey Rosnovsky ◽  
Eduard Mel'nikov ◽  
...  
Keyword(s):  
Experimental Study ◽  
Radioactive Waste ◽  
Energy Distribution ◽  
Gamma Radiation ◽  
Measurement Method ◽  
Activity Measurement ◽  
Radionuclide Composition

The article analyses the results of application of the radioactive waste activity measurement method based on measuring the energy distribution of gamma radiation near the container at the Novovoronezh NPP. The proposed method is applied to homogeneous radioactive waste and provides a reduction of the characterization costs. The results of an experimental study of the method and proposals for its improvement are presented.

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