Microscopic deposition-property relationships in microbial-induced consolidation of coal dusts

Qingshan Wang; Xiangming Hu; Yanyun Zhao; Ningjun Jiang; Xiaoniu Yu; Yue Feng; Juan Zhang

doi:10.1016/j.envres.2023.117956

Microscopic deposition-property relationships in microbial-induced consolidation of coal dusts

Environ Res. 2024 Mar 1:244:117956. doi: 10.1016/j.envres.2023.117956. Epub 2023 Dec 19.

Authors

Qingshan Wang¹, Xiangming Hu¹, Yanyun Zhao², Ningjun Jiang³, Xiaoniu Yu⁴, Yue Feng¹, Juan Zhang¹

Affiliations

¹ College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, Shandong, 266590, China; Key Laboratory of Mining Disaster Prevention and Control, Shandong University of Science and Technology, Qingdao, Shandong, 266590, China.
² College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, Shandong, 266590, China; Key Laboratory of Mining Disaster Prevention and Control, Shandong University of Science and Technology, Qingdao, Shandong, 266590, China; Institute of Yellow River Delta Earth Surface Processes and Ecological Integrity, Shandong University of Science and Technology, Qingdao, Shandong, 266590, China. Electronic address: skd995627@sdust.edu.cn.
³ Institute of Geotechnical Engineering, Southeast University, Nanjing, China; Department of Civil and Environmental Engineering, University of Hawaii at Manoa, Honolulu, USA.
⁴ Jiangsu Key Laboratory of Construction Materials, Southeast University, Nanjing, 211189, China; School of Civil and Environmental Engineering, Nanyang Technological University, Singapore, 639798, Singapore.

PMID: 38128598
DOI: 10.1016/j.envres.2023.117956

Abstract

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 CaCO₃ 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 CaCO₃ induced by calcium chloride and calcium lactate was aggregate deposited. Aggregate deposited CaCO₃ was small in volume, showed the distribution of aggregation in the central area and loose outside, and mosaiced pores. CaCO₃ induced by calcium nitrate was surface deposition due to attached biomass. Surface deposition was mostly large volume CaCO₃ 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 CaCO₃ bonding between coal dust particles under different deposition. The two-factor model based on porosity and CaCO₃ 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.

Keywords: CT scanning; Coal dust; Deposition characteristics; Erosion resistance; Microbial induced carbonate precipitation.

MeSH terms

Biomass
Calcium
Coal*
Dust* / analysis
Minerals

Substances

Dust
Coal
Minerals
Calcium