| Autor: |
Wang, Qingshan1,2 (AUTHOR), Hu, Xiangming1,2 (AUTHOR), Zhao, Yanyun1,2,3 (AUTHOR) skd995627@sdust.edu.cn, Jiang, Ningjun4,5 (AUTHOR), Yu, Xiaoniu6,7 (AUTHOR), Feng, Yue1,2 (AUTHOR), Zhang, Juan1,2 (AUTHOR) |
| Předmět: |
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| Zdroj: |
Environmental Research. Mar2024, Vol. 244, pN.PAG-N.PAG. 1p. |
| Abstrakt: |
In recent years, the preparation of new microbial dust suppressants based on microbial induced carbonate precipitation (MICP) technology through enriched urease-producing microbial communities has become a new topic in the field of coal dust control. The deposition of CaCO 3 was the key to suppress coal dust. However, deposition characteristics in the field is not sufficient and the relationship between deposition characteristics and erosion resistance is not clear, which hinders the development of engineering application of new microbial dust suppressant. Therefore, based on X-CT technology, this paper observed and quantified micro-deposition of bio-consolidated coal dust with different calcium sources. Furthermore, a conceptual framework for deposition was proposed and its correlation with erosion resistance was revealed. The results showed that CaCO 3 induced by calcium chloride and calcium lactate was aggregate deposited. Aggregate deposited CaCO 3 was small in volume, showed the distribution of aggregation in the central area and loose outside, and mosaiced pores. CaCO 3 induced by calcium nitrate was surface deposition due to attached biomass. Surface deposition was mostly large volume CaCO 3 expanding from the inside out, which could cover coal dust to a high degree and completely cemented pores. In addition, the threshold detachment velocity of coal dust cemented by surface deposition was increased by 17.6–19.1% compared to aggregate deposition. This depended on the abundance and strength of CaCO 3 bonding between coal dust particles under different deposition. The two-factor model based on porosity and CaCO 3 coverage can well express relationship between erosion resistance and depositional characteristics. Those results will help the engineering application of MICP technology in coal dust suppression. • Different depositional property for different calcification condition. • Aggregate deposition formed "bridges" between particles. • Surface deposition formed calcite layer with a thickness of 6–7 μm. • Differences in deposition caused to 17.6–19.1% variation in TDV. [ABSTRACT FROM AUTHOR] |
| Databáze: |
GreenFILE |
| Externí odkaz: |
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