|   | 
Details
   web
Records
Author Wang, B.; Luo, Y.; Liu, J.-hui; Li, X.; Zheng, Z.-hong; Chen, Q.-qian; Li, L.-yao; Wu, H.; Fan, Q.-ren
Title Ion migration in in-situ leaching (ISL) of uranium: Field trial and reactive transport modelling Type Journal Article
Year 2022 Publication Journal of Hydrology Abbreviated Journal
Volume 615 Issue Pages 128634
Keywords Acid in situ leaching, Banyan-Uul uranium deposit, Influence area, Reactive transport, Sensitivity analysis
Abstract Acid in-situ leaching (ISL) can be used as a mining technique for in situ uranium recover from underground. Acids and oxidants as lixiviants were continuously injected into a sandstone-type uranium deposit in Bayan-Uul (China). It was conducted to facilitate the dissolution of uranium minerals to generate uranyl ions, which could then be extracted for the recovery of uranium resources by the pumping cycle. A reactive transport model based on PHAST was developed to investigate the dynamic reactive migration process of uranium. The simulated results well reproduce the fluid dynamic evolution in the injecting and pumping units, as well as the dynamic release of uranium. The simulated leaching area indicates that the uranium ore leaching area was much larger than the acidification area. In addition, the pollution plume of uranium and acid water was larger than that of the leaching area, which can be used as a reference for uranium mining schemes. Furthermore, the parameter sensitivity analysis indicates the volume fraction of uranium ore and the reaction rate were the main factors affecting uranium leaching efficiency. Without considering the blockage of pores by precipitation, the Fe2+ in the reinjection fluid had a significant negative influence on uranium leaching.
Address
Corporate Author Thesis
Publisher Place of Publication (up) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-1694 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number THL @ christoph.kuells @ wang_ion_2022 Serial 195
Permanent link to this record
 

 
Author Klimkova, S.; Cernik, M.; Lacinova, L.; Filip, J.; Jancik, D.; Zboril, R.
Title Zero-valent iron nanoparticles in treatment of acid mine water from in situ uranium leaching Type Journal Article
Year 2011 Publication Chemosphere Abbreviated Journal
Volume 82 Issue 8 Pages 1178-1184
Keywords Acid mine water, Contaminant removal, Surface stabilizing shell, Water treatment, Zero-valent iron nanoparticles
Abstract Acid mine water from in situ chemical leaching of uranium (Straz pod Ralskem, Czech Republic) was treated in laboratory scale experiments by zero-valent iron nanoparticles (nZVI). For the first time, nZVI were applied for the treatment of the real acid water system containing the miscellaneous mixture of pollutants, where the various removal mechanisms occur simultaneously. Toxicity of the treated saline acid water is caused by major contaminants represented by aluminum and sulphates in a high concentration, as well as by microcontaminants like As, Be, Cd, Cr, Cu, Ni, U, V, and Zn. Laboratory batch experiments proved a significant decrease in concentrations of all the monitored pollutants due to an increase in pH and a decrease in oxidation–reduction potential related to an application of nZVI. The assumed mechanisms of contaminants removal include precipitation of cations in a lower oxidation state, precipitation caused by a simple pH increase and co-precipitation with the formed iron oxyhydroxides. The possibility to control the reaction kinetics through the nature of the surface stabilizing shell (polymer vs. FeO nanolayer) is discussed as an important practical aspect.
Address
Corporate Author Thesis
Publisher Place of Publication (up) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0045-6535 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number THL @ christoph.kuells @ klimkova_zero-valent_2011 Serial 196
Permanent link to this record
 

 
Author Uhrie, J.L.; Drever, J.I.; Colberg, P.J.S.; Nesbitt, C.C.
Title In situ immobilization of heavy metals associated with uranium leach mines by bacterial sulfate reduction Type Journal Article
Year 1996 Publication Hydrometallurgy Abbreviated Journal
Volume 43 Issue 1 Pages 231-239
Keywords
Abstract Laboratory experiments with mixed populations of sulfate-reducing bactreria were shown to mediate the removal of milligrams/liter concentrations of uranium, selenium, arsenic and vanadium from aqueous solution via reduction, precipitation and adsorption. Results of laboratory experiments with active sulfidogenic biomass suggest that injection of sulfate and a source of carbon could enhance anaerobic microbial activity in and around uranium leach mines leading to in situ immobilization contaminating metals.
Address
Corporate Author Thesis
Publisher Place of Publication (up) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-386x ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number THL @ christoph.kuells @ uhrie_situ_1996 Serial 197
Permanent link to this record
 

 
Author Zhao, Y.; Li, X.; Lei, L.; Chen, L.; Luo, Z.
Title Permeability evolution mechanism and the optimum permeability determination of uranium leaching from low-permeability sandstone treated with low-frequency vibration Type Journal Article
Year 2023 Publication Journal of Rock Mechanics and Geotechnical Engineering Abbreviated Journal
Volume 15 Issue 10 Pages 2597-2610
Keywords Chemical reactive rate, Low-frequency vibration, Low-permeability sandstone, Optimum permeability, Permeability evolution mechanism, Uranium migration
Abstract Low-frequency vibrations can effectively improve natural sandstone permeability, and higher vibration frequency is associated with larger permeability. However, the optimum permeability and permeability evolution mechanism for uranium leaching and the relationship between permeability and the change of chemical reactive rate affecting uranium leaching have not been determined. To solve the above problems, in this study, identical homogeneous sandstone samples were selected to simulate low-permeability sandstone; a permeability evolution model considering the combined action of vibration stress, pore water pressure, water flow impact force, and chemical erosion was established; and vibration leaching experiments were performed to test the model accuracy. Both the permeability and chemical reactions were found to simultaneously restrict U6+ leaching, and the vibration treatment increased the permeability, causing the U6+ leaching reaction to no longer be diffusion-constrained but to be primarily controlled by the reaction rate. Changes of the model calculation parameters were further analyzed to determine the permeability evolution mechanism under the influence of vibration and chemical erosion, to prove the correctness of the mechanism according to the experimental results, and to develop a new method for determining the optimum permeability in uranium leaching. The uranium leaching was found to primarily follow a process consisting of (1) a permeability control stage, (2) achieving the optimum permeability, (3) a chemical reactive rate control stage, and (4) a channel flow stage. The resolution of these problems is of great significance for facilitating the application and promotion of low-frequency vibration in the CO2 + O2 leaching process.
Address
Corporate Author Thesis
Publisher Place of Publication (up) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1674-7755 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number THL @ christoph.kuells @ zhao_permeability_2023 Serial 198
Permanent link to this record
 

 
Author Zeng, S.; Shen, Y.; Sun, B.; Zhang, N.; Zhang, S.; Feng, S.
Title Pore structure evolution characteristics of sandstone uranium ore during acid leaching Type Journal Article
Year 2021 Publication Nuclear Engineering and Technology Abbreviated Journal
Volume 53 Issue 12 Pages 4033-4041
Keywords Acid method, In situ leaching, Nuclear magnetic resonance, Pore characteristic, Sandstone uranium ore
Abstract To better understand the permeability of uranium sandstone, improve the leaching rate of uranium, and explore the change law of pore structure characteristics and blocking mechanism during leaching, we systematically analyzed the microstructure of acid-leaching uranium sandstone. We investigated the variable rules of pore structure characteristics based on nuclear magnetic resonance (NMR). The results showed the following: (1) The uranium concentration change followed the exponential law during uranium deposits acid leaching. After 24 h, the uranium leaching rate reached 50%. The uranium leaching slowed gradually over the next 4 days. (2) Combined with the regularity of porosity variation, Stages I and II included chemical plugging controlled by surface reaction. Stage I was the major completion phase of uranium displacement with saturation precipitation of calcium sulfate. Stage II mainly precipitated iron (III) oxide-hydroxide and aluminum hydroxide. Stage III involved physical clogging controlled by diffusion. (3) In the three stages of leaching, the permeability of the leaching solution changed with the pore structure, which first decreased, then increased, and then decreased.
Address
Corporate Author Thesis
Publisher Place of Publication (up) Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1738-5733 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number THL @ christoph.kuells @ zeng_pore_2021 Serial 199
Permanent link to this record