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[en] A method of designing a stratified cooling channel for managing the excess heat of a thermal discharge is presented. The cooling channel is connected to a larger body of water such as a river, lake, or ocean. A continuous exchange flow with a larger body of water allows mixing to play an important role in reducing the temperature of a discharge in the cooling channel. The equations governing the flow and temperature in a deep cooling channel are derived from basic principles of momentum and heat balance. The numerical solutions show that most of the thermal impact of a heated discharge may be confined to within the boundaries of the cooling channel, minimizing the ecological impact on the natural environment. An example is used to demonstrate the method of designing a cooling channel. The example shows that cooling channels could operate under thermal loading conditions significantly higher than those required in cooling ponds
[en] The Kursk TETs-1 heating and electric power plant is discussed as an illustration of preventing thermal contamination of its water supply (River Seim) by circulating water. An effective water supply system is taken to be one for which the overheating of the water at a monitoring site (near the outlet location) does not exceed an approved level for the water use conditions. The required cooling capacity of a spray pond for circulating and flow-through water supplies is determined.
[en] FR configuration comparison in the JAEA feasibility study (FS) from 1996 to 2006 has been summarized. A brief description of a FS pool concept and material mass comparison between FS pool and loop concepts have been provided. A shot review of pool designs has also been provided showing the FS pool concept has the most compact reactor vessel diameter. (author)
[en] Since 2004, Europe supports the strengthening of the European actinides sciences scientific community through the funding of dedicated networks: (i) from 2004 to 2008, the ACTINET6 network of excellence (6. Framework Programme) gathered major laboratories involved in nuclear research and a wide range of academic research organisations and universities with the specific aims of funding and implementing joint research projects to be performed within the network of pooled facilities; (ii) from 2009 to 2013, the ACTINET-I3 integrated infrastructure initiative (I3) supports the cost of access of any academics in the pooled EU hot laboratories. In this continuation, TALISMAN (Trans-national Access to Large Infrastructures for a Safe Management of Actinides) gathers now the main European hot laboratories in actinides sciences in order to promote their opening to academics and universities and strengthen the EU-skills in actinides sciences. Furthermore, a specific focus is set on the development of advanced cutting-edge experimental and spectroscopic capabilities, the combination of state-of-the art experimental with theoretical first-principle methods on a quantum mechanical level and to benefit from the synergy between the different scientific and technical communities. ACTINET-I3 and TALISMAN attach a great importance and promote the Education and Training of the young generation of actinides scientists in the Trans-national access but also by organizing Schools (general Summer Schools or Theoretical User Lab Schools) or by granting students to attend International Conference on actinide sciences. (authors)
[en] The 'Cooling Pond' scenario was designed to test models for radioactive contamination of aquatic ecosystems, based on data from the Chernobyl Nuclear Power Plant cooling pond, which was heavily contaminated in 1986 as a result of the reactor accident. The calculation tasks include (a) reconstruction of the dynamics of radionuclide transfer and bioaccumulation in aquatic media and biota following the accident; (b) assessment of doses to aquatic biota; and (c) assessment of potential doses and radiation risks to humans from consumption of contaminated fish. Calculations for the Scenario were performed by 19 participants using 6 different models: LAKECO-B (Netherlands); LAKEPOND (Romania); POSOD (USA); WATER, GIDRO and ECOMOD-W (Russia). For all endpoints, model predictions were compared with the test data, which were derived from the results of direct measurements and independent dose estimates based on measurements. Most of the models gave satisfactory agreement for some portions of the test data, although very few participants obtained good agreement with all criteria for model testing. The greatest level of difficulty was with the prediction of non-equilibrium radioecological processes in the first year after the accident (1986). The calculations 5 for this scenario gave modellers a unique opportunity to test their models using an independent data base and to analyse the advantages and weaknesses of different model approaches. The use of post-Chernobyl data in such a scenario is also recommended for use in training students in the field of radioecology and environmental protection. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)
[en] Dealing with the challenge of recharging Wabamun Lake by treating nearby cooling pond water, fed by the North Saskatchewan River, and returning it to the lake, is discussed. To deal with the problem, TransAlta Utilities constructed a treatment plant in 1997 next to the 2,029 MW Sundance power plant to mitigate the effect the power plant's ongoing and historical effect on the lake's water level. The objective of the treatment plant is to treat cooling pond water and return it to the lake to raise water levels there, which have been significantly reduced over the last 25 years mostly by power plant intake, but also by lack of rainfall, surface runoff, and natural evaporation. At the Treatment Facility the water to be treated is first chlorinated to kill zooplankton, algae and bacteria, followed by adjusting the pH using sulfuric acid. Alum coagulant is used to destabilize colour, particles and colloids. The next step is feeding the water to the Actiflo clarifiers which use microsand to provide increased surface area for floc attachment, and to act as ballast. Clarified water from the Actiflo system is then fed to to the Dusenflo filters to remove the largest particles of suspended solids, and through a finer sand media to remove the remaining turbidity, colour and bacteria. Thiosulfate is used in the ozonation system to inactivate any remaining bacteria and zooplankton in the filtered water, before discharging it to the lake. The cooling towers, which are part of the system, ensure that the treated water returned to the lake is kept at a constant temperature, varying no more than three degrees C from the lake water temperature. 3 figs
[en] This study continues investigations into the development dynamics of phytoplankton and hydrochemical and meteorological factors over a periods of 26 years in the cooling pond of the Mayak Production Association in the Kyzyl-Trash Lake. The aim is to evaluate the long-term oscillations in phytoplankton owing to changes in hydrochemical and meteorological factors. 6 refs., 2 figs., 1 tab
[en] The article deals with the implementation of the principles and guidelines of the EU in the field of water management, protection and assessment of the aquatic environment quality in aspect of applying the EU Water Framework Directive 2000/60, and for organization of hydrobiological monitoring of cooling systems and technical water supply of Ukrainian nuclear power plants (NPPs). Currently, Ukraine has adopted new state documents that regulate the procedure for conducting the state water monitoring. However, as in the Water Framework Directive, the documents focus on the monitoring of natural water bodies (rivers and lakes). The cooling ponds of Ukrainian NPPs are artificial water bodies, and have each unique operating mode and design features. They are located in different climatic zones. Therefore, environmental and hydrobiological monitoring should be carried out taking into account these features. The existing principles of surface water monitoring do not take into account the need to control both the influence of anthropogenic factors on the environment, and also the reverse influence of biotic factors on the reliability of operation of NPP technical systems. The Water Framework Directive suggests for assessments to use a comparative analysis of ecosystems of artificial water bodies with “similar” or close to them in nature. However, for cooling ponds there are no analogues in nature, therefore, it is necessary to search the adequate approaches to assess the ecological state (ecological potential) of these water bodies. And in a broader aspect, an assessment of the whole water techno-ecosystem is necessary. The article outlines the basic principles and provisions of the new standard of SE “NNEGC ‘Energoatom’” in the field of environmental protection SOU NAEK 178:2019 “Procedure of hydrobiological monitoring developing for a cooling ponds, cooling systems and water supply system of NPPs with VVER-type reactors”. When creating the Standard, the developers took into account the necessity of using hydrobiological indicators in monitoring and assessment, as required by the Water Framework Directive. On the other hand, this document takes into account the peculiarities of nuclear techno-ecosystems of NPPs. Hydrobiological monitoring of NPP techno-ecosystems is aimed two main tasks: to identify probable and real causes of biological disturbances in the operation of NPP water supply systems and as well as to identify the factors which lead to negative impact of technical ecosystems on the surrounding hydro ecosystems due to non-radiation exposure.
[en] Environmental monitoring programs often require accurate determination of sampling site locations in aquatic environments. This is especially true when a open-quotes pictureclose quotes of high resolution is needed for observing a changing variable in a given area and location is assumed to be important to the distribution of that variable. Sample site location can be difficult if few visible land marks are available for reference on a large body of water. The use of navigational systems such as Global Positioning System (GPS) and its predecessor, Loran-C, provide an excellent method for sample site location. McFarland (1992) discusses the practicality of GPS for location determination. This article discusses the use of Loran-C in a sampling scheme implemented at the South Texas Project Electrical Generating Station (STPEGS), Wadsworth, Texas