PMID- 35150426 OWN - NLM STAT- MEDLINE DCOM- 20220623 LR - 20220623 IS - 1614-7499 (Electronic) IS - 0944-1344 (Linking) VI - 29 IP - 30 DP - 2022 Jun TI - Experimental study of microorganism-induced calcium carbonate precipitation to solidify coal gangue as backfill materials: mechanical properties and microstructure. PG - 45774-45782 LID - 10.1007/s11356-022-18975-9 [doi] AB - The treatment of coal gangue solid waste and microbially induced calcium carbonate precipitation (MICP) consolidate technology is a focus of research at home and abroad. MICP technology was used to solidify and cement coal gangue particles and endows them with a certain strength. The process does not use the traditional cementitious material (Portland cement) and is eco-friendly and pollution-free. The mechanical properties including unconfined compressive strength, CaCO(3) content, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and infrared spectroscopy (FTIR) were used for macroscopic and microscopic analyses. The results show that the average strength of CG-based bio-mineralized backfill materials reaches 1.55 MPa and the maximum strength is 2.17 MPa, suggesting the potential for its use as an underground fill. Compared with unmineralized gangue, the CaCO(3) crystal content in CG-based mineralized material is increased by 8.75% on average, and the maximum content is 13.34%. In the process of bacterial liquid perfusion, there is uneven distribution of bacteria in the material, which results in fewer CaCO(3) crystals being locally generated in the mineralized material and affects the overall compressive strength of gangue columns. Moreover, the greater the amount of calcium carbonate, the larger the strength of the mineralized material. SEM analysis results indicate that the gaps between gangue particles are filled with CaCO(3) crystals, and the calcium carbonate crystals are mostly polyhedral, showing stacked growth and contain a small number of spherical crystals that exist alone. The results of FTIR and EDS analysis show that the CaCO(3) crystals in the mineralized material are mainly in the form of calcite, followed by a small amount of vaterite. Comprehensive analysis demonstrates that the preparation of CG-based bio-mineralized backfilling materials is successful, and this experiment provides new ideas and methods for the treatment of solid waste such as coal gangue and building material waste. CI - (c) 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature. FAU - Wang, Zhaojun AU - Wang Z AD - State Key Laboratory of Coal Resources and Safe Mining, University of Mining & Technology, XuzhouChin, 221116, Jiangsu, China. AD - School of Mines, China University of Mining & Technology, Xuzhou, 221116, Jiangsu, China. FAU - Zhang, Jixiong AU - Zhang J AD - State Key Laboratory of Coal Resources and Safe Mining, University of Mining & Technology, XuzhouChin, 221116, Jiangsu, China. cumtzjxiong@163.com. AD - School of Mines, China University of Mining & Technology, Xuzhou, 221116, Jiangsu, China. cumtzjxiong@163.com. FAU - Li, Meng AU - Li M AD - State Key Laboratory of Coal Resources and Safe Mining, University of Mining & Technology, XuzhouChin, 221116, Jiangsu, China. limeng1989@cumt.edu.cn. AD - School of Mines, China University of Mining & Technology, Xuzhou, 221116, Jiangsu, China. limeng1989@cumt.edu.cn. FAU - Guo, Shijie AU - Guo S AD - State Key Laboratory of Coal Resources and Safe Mining, University of Mining & Technology, XuzhouChin, 221116, Jiangsu, China. AD - School of Mines, China University of Mining & Technology, Xuzhou, 221116, Jiangsu, China. FAU - Zhang, Jiaqi AU - Zhang J AD - State Key Laboratory of Coal Resources and Safe Mining, University of Mining & Technology, XuzhouChin, 221116, Jiangsu, China. AD - School of Mines, China University of Mining & Technology, Xuzhou, 221116, Jiangsu, China. FAU - Zhu, Gaolei AU - Zhu G AD - State Key Laboratory of Coal Resources and Safe Mining, University of Mining & Technology, XuzhouChin, 221116, Jiangsu, China. AD - School of Mines, China University of Mining & Technology, Xuzhou, 221116, Jiangsu, China. LA - eng GR - 2018YFC0604704/the national key r&d program of china/ GR - 51725403/the national science fund for distinguished young scholars/ GR - 52004271/the national natural science foundation of china/ PT - Journal Article DEP - 20220212 PL - Germany TA - Environ Sci Pollut Res Int JT - Environmental science and pollution research international JID - 9441769 RN - 0 (Coal) RN - 0 (Solid Waste) RN - H0G9379FGK (Calcium Carbonate) SB - IM MH - *Calcium Carbonate/chemistry MH - *Coal/analysis MH - Construction Materials MH - Solid Waste MH - Spectrometry, X-Ray Emission OTO - NOTNLM OT - Backfilling material OT - Mechanical properties OT - Microbial mineralization OT - Microstructure OT - Solid-waste coal gangue EDAT- 2022/02/13 06:00 MHDA- 2022/06/24 06:00 CRDT- 2022/02/12 12:08 PHST- 2021/07/27 00:00 [received] PHST- 2022/01/26 00:00 [accepted] PHST- 2022/02/13 06:00 [pubmed] PHST- 2022/06/24 06:00 [medline] PHST- 2022/02/12 12:08 [entrez] AID - 10.1007/s11356-022-18975-9 [pii] AID - 10.1007/s11356-022-18975-9 [doi] PST - ppublish SO - Environ Sci Pollut Res Int. 2022 Jun;29(30):45774-45782. doi: 10.1007/s11356-022-18975-9. Epub 2022 Feb 12.