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Wielofizyczna optymalizacja modelu THM oraz niepewność propagacji ciepła wokół eksperymentalnego składowiska odpadów jądrowych

Wojnarowicz Matthias, Madaschi Aldo, Laloui Lyesse

Inżynieria Morska i Geotechnika

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2023

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nr 4

159--166

PL

Problem dużej emisji ciepła podczas składowania odpadów jądrowych w głębokich formacjach geologicznych. Modelowanie numeryczne propagacji ciepła w górotworze w celu zbadania interakcji termo-hydro-mechanicznych (THM). Weryfikacja i kalibracja modelu numerycznego THM 3D za pomocą eksperymentu w dużej skali z uwzględnieniem elementów niepewności i probabilistyki.

EN

The problem of high heat emission during repository of nuclear waste in deep geological formations. Numerical modeling of heat propagation in the rock mass to study thermo-hydro-mechanical (THM) interactions. Verification and calibration of the THM 3D numerical model using a large-scale experiment, taking into account the elements of uncertainty and probability.

2

Szkła dla immobilizacji odpadów radioaktywnych

Stoch P., Ciecińska M., Stoch A.

Szkło i Ceramika

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2017

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R. 68, nr 2

21--25

PL

Witryfikacja odpadów radioaktywnych jest jedną z najskuteczniejszych metod ich immobilizacji. Polega ona na wprowadzeniu składników odpadu w strukturę odpornych chemicznie szkieł. Jest to jedna z nielicznych metod, która pozwala związać pierwiastki radioaktywne i zapobiec ich rozprzestrzenianiu się w bardzo długim okresie. Do tego celu stosuje się szkła borokrzemianowe lub fosforanowe. W pracy przedstawiono podział, źródła pochodzenia oraz podstawy gospodarki odpadami radioaktywnymi, jak również metody ich immobilizacji. Przeprowadzono przegląd stosowanych obecnie szkieł do ich witryfikacji oraz zasady stosowane przy projektowaniu ich składu.

EN

Radioactive waste vitrification is a one of the most effective method of its immobilization. It is based on the incorporation of the waste constituents into the structure of chemically durable glasses. It is one of the few methods which can bind radioactive elements and prevent their spread over a very long period of time. For this purpose a borosilicate or phosphate glasses are used. The paper presents the division, the sources of origin and the basis for radioactive waste management, as well as methods of its immobilization. A review of currently used glasses to the vitrification and the rules applied in the design of their composition is presented.

3

Wpływ temperatury na wytrzymałość i sprężystość skał

Bukowska M., Sygała A.

Wiadomości Górnicze

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2015

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R. 66, nr 10

506--519

PL

Z uwagi na podziemne zgazowanie węgla, składowanie odpadów nuklearnych czy pozyskiwanie energii geotermalnej, zmiany właściwości geomechanicznych pod wpływem temperatury, mają istotne znaczenie. W artykule przedstawiono badania zmian właściwości wytrzymałościowych i sprężystych karbońskich skał osadowych (iłowców i piaskowców), po działaniu temperatury z zakresu od temperatury pokojowej do 1000-1200 °C. Zmiany wielkości takich parametrów jak wytrzymałość na jednoosiowe ściskanie, wytrzymałość resztkowa oraz moduł Younga E. określono w próbach jednoosiowego ściskania, przeprowadzonych w serwosterowanej maszynie wytrzymałościowej. Nowym zagadnieniem poruszanym w artykule jest zbadanie wpływu temperatury na wartość wytrzymałości resztkowej, która obrazuje nośność pokrytyczną skał. Do tej pory badania zmian parametrów pokrytycznych pod wpływem temperatury nie były realizowane w tego typu eksperymentach.

EN

Because of the underground coal gasification, storage of nuclear wastes or acquiring of geothermal energy, the changes of geomechanical properties under the influence of temperature are of essential important. The article presents a study on changes in the strength and elasticity properties of carboniferous sedimentary rocks (sandstones and clay stones) under the impact of temperature ranging from a room temperature to 1000-1200 °C. Changes in the value of parameters such as uniaxial compression, residual strength and Youngs E modulus were determined in uniaxial compression tests, conducted in servo controlled testing machine. An issue discussed in the article consists in examination of the effect of temperature on the value of residual strength, which depicts post critical load capacity of the rocks. Up till now, the study of changes of post critical parameters under the impact of temperature were not carried out in this type of experiments.

4

Mössbauer spectroscopy study of 60P2O5-40Fe2O3 glass crystallization

Stoch P., Stoch A.

Nukleonika

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2015

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Vol. 60, No. 1

133--136

EN

60P2O5-40Fe2O3 glass was synthesized and 57Fe Mössbauer spectroscopy study was presented. The main goal of the research was to investigate structural changes of local environment of iron ions during gradual crystallization of the glass. It was observed that some changes were evidenced at temperature of heat treatment higher than 400°C, above which content of tetrahedrally coordinated Fe3+ was increased in cost of octahedral sites. This led to formation of areas of nucleation of α-FePO4. Crystallization of α-Fe3(P2O7)2 and Fe2P2O7 was also observed.

5

Transmutation: reducing the storage time of spent fuel

Mazgaj P., Darnowski P.

Journal of Power Technologies

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2014

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Vol. 94, nr 5

27--34

EN

Transmutation can reduce the storage time of spent fuel. Efficient transmutation requires a high flux of neutrons and can therefore be done only in nuclear reactors. The article shows the concepts of different solutions of transmutation in nuclear reactors. Knowledge of transmutation is supplemented by information on spent fuel and its radiotoxicity.

6

Mössbauer spectroscopy study of 60P2O5-40Fe2O3 glass

Stoch P., Ciecińska M., Zachariasz P., Suwalski J., Górski L., Wójcik T.

Nukleonika

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2013

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Vol. 58, No. 1

63-66

EN

A 57Fe Mössbauer spectroscopy study is presented. The main goal of the research was to investigate the structural information of the glass-like the coordination numbers and redox ratio of the iron. Most of the iron, about 80%, is present in the glass as Fe3+, which is composed of tetrahedral (57%) and octahedral (23%) coordinated iron. The rest of the iron, about 20%, is in the oxidation state Fe2+. This iron could be mostly present as VIFe2+, but five-fold coordinated iron is also possible. Finally, the structural model of the synthesized 60P2O5-40Fe2O3 glass was proposed.

7

Environmental degradation of materials for nuclear waste repositories engineered barriers

Rebak R.B.

Advances in Materials Science

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2007

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Vol. 7, nr 2(12)

40-53

EN

Several countries are considering geological repositories for the storage of nuclear waste. Most of the environments for these repositories will be reducing in nature, except for the repository in the DS, which is going to be oxidizing. For the reducing repositories, alloys such as carbon steel, copper, stainless steels and titanium are being evaluated. For the repository in the DS, same of the most corrosion resistant commercially available alloys are being investigated. This paper presents a summary of the behavior of the different materials under consideration for the repositories and the current understanding of the degradation modes of the proposed alloys in ground water environments from the point of view of general corrosion, localized corrosion and environmentally assisted cracking.

8

Development of environmental purification materials with smart functions

Yamada H., Watanabe Y., Tamura K.

Nukleonika

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2006

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Vol. 51,suppl.1

61-67

EN

For an environmental-friendly sustainable society, the global environmental problems should be solved. Here we outline our recent results of environment purification materials with smart functions. For the effective adsorbent for remediation process, zeolite coated with layered double hydroxide (LDH) was prepared by the precipitation of LDH on zeolite-LTA under hydrothermal treatment. This multifunctional material has a possible application for simultaneous uptake of harmful cations and anions, and minimizes environmental pollution during municipal and industrial water management. For novel material for the nuclear waste management, zeolite with hydroxyapatite layers on its surface was obtained by a hydrothermal method on the basis of the cation exchange of Ca2+ in zeolite for NH4+ in solution. The novel nanocomposite is an ideal material for adsorbing and fixing radioactive elements for geological time-scale.

9

Adsorption of strontium, europium and americium(III) ions on a novel adsorbent Apatite II

Krejzler J., Narbutt J.

Nukleonika

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2003

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Vol. 48, nr 4

171-175

EN

A novel material, Apatite II, obtained from a natural source, has been determined to be a good adsorbent for radionuclides of strontium, europium and trivalent actinides, but not caesium, from neutral aqueous solutions containing common chelating agents and inorganic salts at moderate concentrations. This inexpensive, easily available material seems to be a promising backfill for engineered barriers in nuclear waste repositories. However, encapsulation of the sorbent grains loaded with radiostrontium in the Portland cement matrix results in undesirably high leaching rate for this particular radionuclide.