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1

Zasoby uranu w Polsce – możliwości pozyskiwania uranu ze źródeł niekonwencjonalnych

Kiegiel K., Zakrzewska-Kołtuniewicz G.

Postępy Techniki Jądrowej

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2018

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z. 2

17--22

PL

W artykule omówiono niekonwencjonalne zasoby uranu w Polsce oraz przedyskutowano możliwość ich eksploatacji. Polska posiada jedynie złoża ubogich rud uranu. Najbardziej perspektywiczne zasoby to ordowickie łupki dictyonemowe o koncentracji uranu w zakresie 75-250 ppm oraz piaskowce syneklizy perybałtyckiej, gdzie koncentracja tego pierwiastka dochodzi miejscami nawet 1,5%. Uran może być również odzyskiwany z odpadów przemysłowych różnego pochodzenia, m. in. z przemysłu miedziowego i produkcji nawozów fosforowych.

EN

The article presents the unconventional resources of uranium in Poland and discusses the possibility of their exploitation. In Poland there are only low-grade uranium ores. The most perspective resources of uranium are the Ordovician dictyonema shale with uranium concentrations in the 75-250 ppm range and the sandstones of Peribaltic Syneclise, where the concentration of this element reaches locally up to 1.5%. Uranium can also be recovered from industrial waste of various origins, inter alia, waste from the copper industry and from the production of phosphate fertilizers.

2

Ion exchange investigation for recovery of uranium from acidic pregnant leach solutions

Danko B., Dybczyński R. S., Samczyński Z., Gajda D., Herdzik-Koniecko I., Zakrzewska-Kołtuniewicz G., Chajduk E., Kulisa K.

Nukleonika

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2017

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Vol. 62, No. 3

213--221

EN

The article describes studies on the separation of uranium from acid pregnant leach solutions obtained from Polish uranium ores: dictyonema shales and sandstone rocks. Ion exchange chromatography was applied for uranium sorption, using commercially available, strongly basic anion exchanger, Dowex 1. In model experiments, the influence of degree of crosslinking of Dowex 1 on the efficiency of uranium extraction was investigated. The effect of H2SO4 concentration on the breakthrough curve of uranyl ions for the Dowex 1 resins, of different crosslinking: X4, X8 and X10, was examined. Unexpectedly high increase of exchange capacity of uranium was observed in case of Dowex 1X10. This gives potential opportunity of improving the effectiveness of uranium recovery process. Applying column packed with Dowex 1X10, ‘yellow cake’ with ca. 92% yield and high purity of recovered uranium was obtained. A block diagram of the procedure for uranium and lanthanides extraction from acidic leach liquor has been proposed.

3

Odzysk metali ziem rzadkich z roztworów po ługowaniu magnesów trwałych w procesie zintegrowanym z wykorzystaniem emulsyjnych membran ciekłych

Markowska-Radomska A., Dłuska E., Zakrzewska-Kołtuniewicz G., Miśkiewicz A.

Inżynieria i Aparatura Chemiczna

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2017

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Nr 4

128--129

PL

Przedstawiono koncepcję separacji jonów neodymu i dysprozu (Nd3+ i Dy3+) za pomocą emulsyjnych membran ciekłych-ELM w reaktorze z przepływem Couette’a-Taylora jako procesu zintegrowanego obejmującego wytwarzanie emulsyjnych membran ciekłych i ekstrakcję jonów tych metali z roztworów po ługowaniu magnesów neodymowo-żelazowo-borowych. Zastosowanie reaktora CTF pozwala na zmniejszenie liczby stopni operacyjnych procesu i prowadzenie ekstrakcji w sposób ciągły przy małej konsumpcji rozpuszczalników i przenośników. Opracowano warunki wytwarzania stabilnych membran emulsyjnych ELM’s (nośnik: D2EHPA) o składzie i strukturach odpowiednich do badań procesu separacji Nd3+ i Dy3+.

EN

A concept of separation of metal ions of neodymium and dysprosium by emulsion liquid membranes-ELMs using a Couette- Taylor flow reactor (CTF) as an integrated process combining the creation of emulsion liquid membranes and extraction of Nd3+ and Dy3+ from neodymium-iron-boron leaching solutions is demonstrated. The use of CTF reactor reduces the number of operating process units and enables a continuous extraction with the low consumption of solvents and carriers. Conditions for the preparation of stable ELMs (D2EHPA as a carrier) with composition and structures suitable for a study on Nd3+ and Dy3+ separation were developed.

4

Multibarrier system preventing migration of radionuclides from radioactive waste repository

Olszewska W., Miśkiewicz A., Zakrzewska-Kołtuniewicz G., Lankof L., Pająk L.

Nukleonika

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2015

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Vol. 60, No. 3, part 2

557--563

EN

Safety of radioactive waste repositories operation is associated with a multibarrier system designed and constructed to isolate and contain the waste from the biosphere. Each of radioactive waste repositories is equipped with system of barriers, which reduces the possibility of release of radionuclides from the storage site. Safety systems may differ from each other depending on the type of repository. They consist of the natural geological barrier provided by host rocks of the repository and its surroundings, and an engineered barrier system (EBS). The EBS may itself comprise a variety of sub-systems or components, such as waste forms, canisters, buffers, backfi lls, seals and plugs. The EBS plays a major role in providing the required disposal system performance. It is assumed that the metal canisters and system of barriers adequately isolate waste from the biosphere. The evaluation of the multibarrier system is carried out after detailed tests to determine its parameters, and after analysis including mathematical modeling of migration of contaminants. To provide an assurance of safety of radioactive waste repository multibarrier system, detailed long term safety assessments are developed. Usually they comprise modeling of EBS stability, corrosion rate and radionuclide migration in near fi eld in geosphere and biosphere. The principal goal of radionuclide migration modeling is assessment of the radionuclides release paths and rate from the repository, radionuclides concentration in geosphere in time and human exposure to ionizing radiation.

5

Dictyonema black shale and Triassic sandstones as potential sources of uranium

Kiegiel K., Zakrzewska-Kołtuniewicz G., Gajda D., Miśkiewicz A., Abramowska A., Biełuszka P., Danko B., Chajduk E., Wołkowicz S.

Nukleonika

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2015

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Vol. 60, No. 3, part 2

515--522

EN

The main objective of the present study was an assessment of the possibility of uranium recovery from domestic resources in Poland. In the fi rst stage uranium was leached from the ground uranium ore by using acidic (sulfuric acid or hydrochloric acid) or alkaline (carbonate) solutions. The leaching efficiencies of uranium were dependent on the type of ore and it reached 81% for Dictyonemic shales and almost 100% for sandstones. The novel leaching routes, with the application of the helical membrane contactor equipped with rotating part were tested. The obtained postleaching solutions were concentrated and purifi ed using solvent extraction or ion exchange chromatography. New methods of solvent extraction, as well as hybrid processes for separation and purifi cation of the product, were studied. Extraction with the use of membrane capillary contactors that has many advantages above conventional methods was also proposed as an alternative purification method. The fi nal product U3O8 could be obtained by the precipitation of ‘yellow cake’, followed by calcination step. The results of precipitation of ammonium diuranate and uranium peroxide from diluted uranium solution were presented.