Abstract
Uranium pollution in tailings and its decay products is a global environmental problem. It is of great significance to use economical and efficient technologies to remediate uranium-contaminated soil. In this study, the effects of pH, temperature, and inoculation volume on stabilization efficiency and microbial community response of uranium tailings were investigated by a single-factor batch experiment in the remediation process by mixed sulfate-reducing bacteria (SRB) and phosphate-solubilizing bacteria (PSB, Pantoea sp. grinm-12). The results showed that the optimal parameters of microbial stabilization by mixed SRB-PSB were pH of 5.0, temperature of 25°C, and inoculation volume of 10%. Under the optimal conditions, the uranium in uranium tailings presented a tendency to transform from the acid-soluble state to residual state. In addition, the introduction of exogenous SRB-PSB can significantly increase the richness and diversity of endogenous microorganisms, effectively maintain the reductive environment for the microbial stabilization system, and promote the growth of functional microorganisms, such as sulfate-reducing bacteria (Desulfosporosinus and Desulfovibrio) and iron-reducing bacteria (Geobacter and Sedimentibacter). Finally, PCoA and CCA analyses showed that temperature and inoculation volume had significant effects on microbial community structure, and the influence order of the three environmental factors is as follows: inoculation volume > temperature > pH. The outcomes of this study provide theoretical support for the control of uranium in uranium-contaminated sites.
Highlights
With the rapid development of the nuclear power industry, tests of depleted uranium weapons, and other human activities such as uranium mining and metallurgy, the content of uranium and its compounds in the environment has increased significantly (Brugge et al, 2005)
Effect of pH on Microbial Stabilization Process and Microbial Community Response pH and Eh Changes During the Microbial Stabilization Process Figures 1A,B showed that the initial pH of the medium has no significant effect on the pH and Eh of the stabilization system, and the overall change trend of the three groups remained consistent throughout the 60-day reaction period
With the extension of remediation time, the proportion of acid-soluble uranium decreased and the residual uranium increased in the three groups, indicating that the three systems all could effectively stabilize uranium in the uranium tailings and achieve in situ stabilization of uranium
Summary
With the rapid development of the nuclear power industry, tests of depleted uranium weapons, and other human activities such as uranium mining and metallurgy, the content of uranium and its compounds in the environment has increased significantly (Brugge et al, 2005). Uranium is radioactive, which can cause radiation to the human body, and has strong chemical. Microbial Stabilization of Uranium Tailings toxicity (Lu et al, 2018; Selvakumar et al, 2018). Uranium will cause the decrease in cellular activity and metabolic activity of soil microorganisms after entering soil and affect the whole soil ecosphere; once in the body, uranium and its compounds are apt to bind with phosphorylated peptides, causing damage to the kidneys, bones, and brain (Tang et al, 2021). It is urgent to develop an efficient and economical uranium pollution remediation technology
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
