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Xiuping H, Zheng D, Kang Y, Handong L, Chuan D. Fluoride and acid enrichment in coal fire sponges in the Wuda coalfield, Inner Mongolia, Northern China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 344:123438. [PMID: 38272161 DOI: 10.1016/j.envpol.2024.123438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 01/07/2024] [Accepted: 01/22/2024] [Indexed: 01/27/2024]
Abstract
Coal fire sponges (CFSs) are a type of sponge-like contaminated soil bulge common in coal fire areas. However, the impacts of CFSs on the local environment are not yet understood. Thus, this study investigated soil samples from CFSs in the Wuda coalfield, Inner Mongolia, China, focusing on the acidity, sulfate, and fluorine content. The results showed that the CFSs were highly acidic, with an average pH of 0.76, and contained high levels of SO42- (257.29 × 103 μg/g), total fluorine (TF, 2011.6 μg/g), and water-soluble fluorine (WF, 118.94 μg/g), significantly exceeding those in the regional background soil and indicating that CFSs are a point source of heavy pollution. Soils in the 8000 m2 reclamation zone showed elevated acidity and high SO42- (129.6 × 103 μg/g), TF (1237.8 μg/g), and WF (43.05 μg/g) levels, which was likely the result of the weathering and dissemination of CFS. The CFS samples were rich in hydrogen fluoride, releasing 202.05 ppb of it when heated to 40 °C. Correlation analysis indicated that the acid sulfate soils in CFSs are likely caused by HSO4-/SO42-. Time-of-flight secondary ion mass spectrometry detected four characteristic ions (F-, H3O+, H2SO4+, and HSO4-) in all micro-domains of each sample, indicating that ionic fluorine compounds and sulfuric acid hydrate were found in the CFS samples. Sulfate minerals detected in CFSs included CaSO4, Fe2(SO4)3, CdSO4, NH4HSO4, and Na2SO4. Thus, the results identified CFSs as a transmission channel for contamination, with erosional surface soils as the carrier, for the first time. CFSs pose a serious threat of contamination, albeit over limited areas.
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Affiliation(s)
- Hong Xiuping
- Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation, Huaibei Normal University, Huaibei, 235000, PR China
| | - Du Zheng
- Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation, Huaibei Normal University, Huaibei, 235000, PR China
| | - Yang Kang
- School of Chemical & Environmental Engineering, China University of Mining and Technology, Beijing, 100083, PR China.
| | - Liang Handong
- State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Beijing, 100083, PR China
| | - Du Chuan
- State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Beijing, 100083, PR China
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2
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Liu Y, Qi X, Luo D, Zhang Y, Qin J. Detection and management of coal seam outcrop fire in China: a case study. Sci Rep 2024; 14:4609. [PMID: 38409355 PMCID: PMC10897306 DOI: 10.1038/s41598-024-55304-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Accepted: 02/22/2024] [Indexed: 02/28/2024] Open
Abstract
The outcrop fire area in Rujigou Coal Mine in Ningxia, China has been burning continuously for over 100 years. This not only results in wastage of resources but also poses significant damage to the ecological environment. Previous research on open fire detection has mainly focused on coalfield fire areas, using single method such as infrared remote sensing or surface temperature measurement, magnetic method, electrical method, radon measurement and mercurimetry. However, the outcrop fire area has migrated to deeper parts over the years, conventional single fire zone detection methods are not capable of accurately detecting the extent of the fire zone, inversion interpretation is faced with the problem of many solutions. In fire management, current research focuses on the development of new materials, such as fly ash gel, sodium silicate gel, etc., However, it is often difficult to quickly extinguish outcrop fire areas with a single technique. Considering this status quo, unmanned aerial vehicle (UAV) infrared thermal imaging was employed to initially detect the scope of the outcrop fire area, and then both the spontaneous potential and directional drilling methods were adopted for further scope detection in pursuit of more accurate results. In addition, an applicable fire prevention and extinguishing system was constructed, in which three-phase foam was injected for the purpose of absorbing heat and cooling. Furthermore, the composite colloid was used to plug air leakage channels, and loess was backfilled to avoid re-combustion. The comprehensive detection and control technologies proposed in this study can be applied to eliminating the outcrop fire area and protecting the environment. This study can provide guidance and reference for the treatment of other outcrop fire areas.
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Affiliation(s)
- Yang Liu
- School of Resources and Security, Chongqing Vocational Institute of Engineering, Chongqing, 402260, China.
- School of Safety Engineering, China University of Mining and Technology, Xuzhou, 221000, China.
| | - Xuyao Qi
- School of Safety Engineering, China University of Mining and Technology, Xuzhou, 221000, China
| | - Dayong Luo
- School of Resources and Security, Chongqing Vocational Institute of Engineering, Chongqing, 402260, China
| | - Yongqing Zhang
- School of Resources and Security, Chongqing Vocational Institute of Engineering, Chongqing, 402260, China
| | - Jiangtao Qin
- School of Resources and Security, Chongqing Vocational Institute of Engineering, Chongqing, 402260, China
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Liu Y, Qi X, Luo D, Zhang Y, Qin J. Detection of Spontaneous Combustion Areas of Coal Gangue Dumps and Comprehensive Governance Technologies: A Case Study. ACS OMEGA 2023; 8:47690-47700. [PMID: 38144064 PMCID: PMC10733915 DOI: 10.1021/acsomega.3c05942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 11/16/2023] [Accepted: 11/24/2023] [Indexed: 12/26/2023]
Abstract
Spontaneous combustion of coal gangue dumps not only releases toxic and harmful gases, polluting the environment, but also leads to explosion accidents and casualties due to improper handling. This paper focuses on delineating the fire area, constructing a comprehensive fire prevention and extinguishing system, and restoring the ecological environment. Infrared thermal imaging was used to detect the shallow fire area, while intensive drilling was conducted to detect the deep fire area. The stability of the coal gangue dump was enhanced by perfusing three-phase foam for cooling and using a curing material to fill the cracks. Land reclamation was then performed to restore the ecological environment. The results indicate that spontaneous combustion of coal gangue dumps can trigger the spread of the fire area from the outside to the inside, gradually expanding due to the 'stack effect'. The sources of spontaneous combustion in gangue fire areas are mainly located 3-5 m below the flat surface, and the shallow and deep fire areas are interconnected, posing a significant danger. These research findings can serve as a reference for detecting fire areas in coal gangue dumps and controlling environmental pollution.
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Affiliation(s)
- Yang Liu
- School
of Safety Engineering, China University
of Mining and Technology, Xuzhou 221116, China
- School
of Resources and Security, Chongqing Vocational
Institute of Engineering, Chongqing 402260, China
| | - Xuyao Qi
- School
of Safety Engineering, China University
of Mining and Technology, Xuzhou 221116, China
| | - Dayong Luo
- School
of Resources and Security, Chongqing Vocational
Institute of Engineering, Chongqing 402260, China
| | - Yongqing Zhang
- School
of Resources and Security, Chongqing Vocational
Institute of Engineering, Chongqing 402260, China
| | - Jiangtao Qin
- School
of Resources and Security, Chongqing Vocational
Institute of Engineering, Chongqing 402260, China
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Chan Z, Zhou B, Wang J, Lu Z, Yang Q, Dong Z, Dong K. Long-distance migration law of radon in overburden of abandoned goaf during coal spontaneous combustion. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2023; 270:107284. [PMID: 37634424 DOI: 10.1016/j.jenvrad.2023.107284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 07/26/2023] [Accepted: 08/19/2023] [Indexed: 08/29/2023]
Abstract
The surface isotope radon measurement method (SIRMM) is widely used in fire source detection in abandoned mines. However, studies on the long-distance migration of radon during coal spontaneous combustion are lacking, which hinders the further popularization of this technology in coal fire prevention and control. For this reason, the migration law of radon in overlying strata in fire areas was studied through experiments and numerical simulation. The radon exhalation concentration of coal was found to increase at first and then decrease in the range of 30-350 °C through experiments. The radon concentration reaches the maximum value (557.1 Bq/m3) at 150 °C, which is 6.3 times higher than that at 30 °C. Based on the radon source term obtained by fitting the experimental data, the radon migration model of coal spontaneous combustion in abandoned goaf was constructed, and the dynamic distribution characteristics of the airflow, temperature, and radon concentration fields in the overlying strata area were analyzed. The internal relationship between surface radon and underground fire source was discussed. The simulation results revealed the sharp change in the porosity of the overlying rock causes radon concentration at the interface between the caving and fissure zones to increase continually with the process of spontaneous combustion, providing material and energy support for the long-distance radon migration. When the maximum temperature of the coal pile reaches 70 °C, the concentration of radon released from the coal pile increases rapidly to 13696 Bq/m3, and the radon from the underground space appears on the surface at this temperature. In the range of 70-150 °C, with rapid increase in radon released from coal piles, the surface concentration of radon also increased rapidly to 225 Bq/m3. At the high-temperature stage exceeding 150 °C, the concentration of radon released from coal piles exhibited a downward trend, resulting in a decrease in the rate of increase of radon concentration on the surface. A close relationship between the surface radon concentration and underground fire source temperature in the process of coal spontaneous combustion was observed. In the spatial position, the peak position of radon on the surface was highly consistent with that of the fire source longitudinally, which ensures the accuracy of the SIRMM to determine the location of the hidden fire source. This suggests that the SIRMM can accurately evaluate the fire source's temperature and fire area's development trend.
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Affiliation(s)
- Zhikang Chan
- College of Mining Engineering, Taiyuan University of Technology, Taiyuan, 030024, Shanxi, China
| | - Bin Zhou
- College of Safety and Emergency Management Engineering, Taiyuan University of Technology, Jinzhong, 030600, Shanxi, China.
| | - Junfeng Wang
- College of Mining Engineering, Taiyuan University of Technology, Taiyuan, 030024, Shanxi, China.
| | - Zhifan Lu
- College of Mining Engineering, Taiyuan University of Technology, Taiyuan, 030024, Shanxi, China
| | - Qifan Yang
- College of Mining Engineering, Taiyuan University of Technology, Taiyuan, 030024, Shanxi, China
| | - Zhiyu Dong
- College of Mining Engineering, Taiyuan University of Technology, Taiyuan, 030024, Shanxi, China
| | - Kaili Dong
- College of Mining Engineering, Taiyuan University of Technology, Taiyuan, 030024, Shanxi, China
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Ren SJ, Zhang YN, Song ZY, Xiao Y, Deng J, Shu CM. Initial exploration on potential fire hazards detection from coal spontaneous combustion applied by acoustic wave. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 897:165475. [PMID: 37442472 DOI: 10.1016/j.scitotenv.2023.165475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 06/09/2023] [Accepted: 07/09/2023] [Indexed: 07/15/2023]
Abstract
Coal spontaneous combustion often wastes resources and causes environmental pollution. Rapid and accurate identification of high temperature areas in coal is essential to reducing such combustion and environmental pollution. The acoustic thermometry method has the benefits of large temperature measurement space, non-contact, and high interference resistance. Determining the attenuation characteristics of acoustic waves in loose coal is the basis and premise for realizing acoustic temperature measurement. Four types of bituminous coal were scanned by computer tomography equipment. A self-designed acoustic attenuation test device was used to test coal samples under different temperatures and particle sizes. The study result demonstrates that the distribution characteristics of loose coal voids are mainly related to the particle size. The smaller the particle size range, the more uniform the void distribution. As the size of the coal particles increases, the voids become larger. The acoustic attenuation coefficients of four coal samples showed an increasing trend as frequency increased. The influence of coal particle size distribution on the acoustic attenuation coefficient was greater than that of temperature and metamorphic degree. The peak values of coal sound attenuation for different particle sizes were around 400, 700, 1100, and 1600 Hz. This indicated that the distribution of voids was the main factor affecting the propagation of acoustic waves. By analysing the attenuation mechanism of the acoustic wave in loose coal, the attenuation of acoustic temperature measurement signal was caused by the combined effect of loose coal on acoustic wave absorption and scattering. The study results provide theoretical support for the realization of acoustic wave detection of high temperature point in loose coal spontaneous combustion.
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Affiliation(s)
- Shuai-Jing Ren
- School of Safety Science and Engineering, Xi'an University of Science and Technology, No. 58, Yanta Mid. Rd., Xi'an, Shaanxi 710054, PR China; School of Energy Engineering, Xi'an University of Science and Technology, No. 58, Yanta Mid. Rd., Xi'an, Shaanxi 710054, PR China
| | - Yan-Ni Zhang
- School of Safety Science and Engineering, Xi'an University of Science and Technology, No. 58, Yanta Mid. Rd., Xi'an, Shaanxi 710054, PR China; Shaanxi Key Laboratory of Prevention and Control of Coal Fire, No. 58, Yanta Mid. Rd., Xi'an, Shaanxi 710054, PR China
| | - Ze-Yang Song
- School of Safety Science and Engineering, Xi'an University of Science and Technology, No. 58, Yanta Mid. Rd., Xi'an, Shaanxi 710054, PR China; Shaanxi Key Laboratory of Prevention and Control of Coal Fire, No. 58, Yanta Mid. Rd., Xi'an, Shaanxi 710054, PR China
| | - Yang Xiao
- School of Safety Science and Engineering, Xi'an University of Science and Technology, No. 58, Yanta Mid. Rd., Xi'an, Shaanxi 710054, PR China; Shaanxi Key Laboratory of Prevention and Control of Coal Fire, No. 58, Yanta Mid. Rd., Xi'an, Shaanxi 710054, PR China.
| | - Jun Deng
- School of Safety Science and Engineering, Xi'an University of Science and Technology, No. 58, Yanta Mid. Rd., Xi'an, Shaanxi 710054, PR China; Shaanxi Key Laboratory of Prevention and Control of Coal Fire, No. 58, Yanta Mid. Rd., Xi'an, Shaanxi 710054, PR China
| | - Chi-Min Shu
- Graduate School of Engineering Science and Technology, National Yunlin University of Science and Technology, 123 University Rd., Sec. 3, Douliou, Yunlin 64002, Taiwan, ROC
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Wang T, Wang H, Fang X, Wang G, Chen Y, Xu Z, Qi Q. Research progress and visualization of underground coal fire detection methods. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023:10.1007/s11356-023-27678-8. [PMID: 37233933 DOI: 10.1007/s11356-023-27678-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Accepted: 05/10/2023] [Indexed: 05/27/2023]
Abstract
Underground coal fires are a widespread disaster prevailing in major coal-producing countries globally, posing serious threats to the ecological environment and restricting the safe exploitation of coal mines. The accuracy of underground coal fire detection directly affects the effectiveness of fire control engineering. In this study, we searched 426 articles from the Web of Science database within 2002-2022 as the data foundation and visualized the research contents of the underground coal fire field using VOSviewer and CiteSpace. The results reveal that the investigation of "underground coal fire detection techniques" is currently the focal area of research in this field. Additionally, the "underground coal fire multi-information fusion inversion detection methods" are considered to be the future research trend. Moreover, we reviewed the strengths and weaknesses of various single-indicator inversion detection methods, including the temperature method, gas and radon method, natural potential method, magnetic method, electric method, remote sensing, and geological radar method. Furthermore, we conducted an analysis of the advantages of the multi-information fusion inversion detection methods, which possesses high precision and wide applicability for detecting coal fires, while highlighting the challenges in handling diverse data sources. It is our hope that the research results presented in this paper will provide valuable insights and ideas for researchers involved in the detection and practical research of underground coal fires.
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Affiliation(s)
- Tao Wang
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Haiyan Wang
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
| | - Xiyang Fang
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing, 100083, China
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Gongda Wang
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yuqi Chen
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Ziyuan Xu
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Qingjie Qi
- Chinese Institute of Coal Science, Beijing, 100013, China
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Liu Y, Heng W, Yue H. Quantifying the coal mining impact on the ecological environment of Gobi open-pit mines. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 883:163723. [PMID: 37116813 DOI: 10.1016/j.scitotenv.2023.163723] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 04/08/2023] [Accepted: 04/21/2023] [Indexed: 05/03/2023]
Abstract
Xinjiang is a coal-rich region with many bare rocky and gravelly areas with a delicate and fragile ecology. What is the ecological impact of mining activities? In this study, the Salinity Index (SI-T), New Gravel Land Index (NGLI), and Land Deterioration Index (LD) were used to establish an improved remote sensing ecological index (IRSEI) for the HongShaQuan open-pit coal mine (HSQ). The spatial and temporal evolution of the ecological environment of the HSQ was revealed by IRSEI and unary linear regression analysis. Moreover, the influence of mining on the ecological environment of the Gobi mining area was quantitatively evaluated by the random forest model (RF) and difference-in-difference (DID) approach. The results indicated that the value of IRSEI in HSQ had typically decreased over the last 30a. The ecological environment in most areas of the study area was poor and fair levels. The ecological environment of the whole study area showed a decreasing pattern from southeast to northwest. The proportion of degraded area (52.33 %) was much higher than that of improved area (0.39 %). The average residual before and after mining in HSQ were -0.1011 and -0.2323, respectively, which were much higher than that of the whole study area (-0.0330 and -0.0658, respectively), indicating that the mining activities in HSQ harmed the ecological environment and aggravated the degradation of the ecological environment. The impact of mining activities on the ecological environment from 2000 to 2021 was -0.138 using DID. The results from the multiple regression model (MR), RF, and DID during the pre-mining period (2000-2011) were -0.0709, -0.1011, and -0.1345, respectively, while they became -0.1765, -0.2323, and -0.1963 during the post-mining period (2012-2020), respectively. The latter was worse than the former, all showing that the mining activities of HSQ had resulted in a negative effect on the ecological environment. It also demonstrated that the negative value of mining from the MR, RF, and DID have a very similar change trend and was near in value. This verified the feasibility of DID and RF in quantitative analysis of the ecological environment. The ecological environment quality of HSQ was mainly affected by climate change, and less influenced by mining, the contribution rates of both in the IRSEI improved area were 88.48 % and 11.52 %, respectively; and in the degraded area were 69.45 % and 30.55 %, respectively. Therefore, the Gobi mining area should pay attention to the protection of the ecosystem while developing coal. Planting vegetation can promote the governance and restoration of the ecological environment in the mining area.
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Affiliation(s)
- Ying Liu
- College of Geomatics, Xi'an University of Science and Technology, Xi'an 710054, China; West Mine Ecological Environment Restoration Research Institute, Xi'an University of Science and Technology, Xi'an 710054, Shaanxi, China.
| | - Wenjing Heng
- College of Geomatics, Xi'an University of Science and Technology, Xi'an 710054, China
| | - Hui Yue
- College of Geomatics, Xi'an University of Science and Technology, Xi'an 710054, China; West Mine Ecological Environment Restoration Research Institute, Xi'an University of Science and Technology, Xi'an 710054, Shaanxi, China.
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Wang K, Li Y, Zhai X, Bai G. A method for evaluating the coal spontaneous combustion index by the coefficient of variation and Kruskal-Wallis test: a case study. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:58956-58966. [PMID: 37002521 DOI: 10.1007/s11356-023-26718-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 03/25/2023] [Indexed: 05/10/2023]
Abstract
Focusing on the precise prediction of coal spontaneous combustion (CSC), temperature-programmed experiment was conducted to identify the coal spontaneous combustion indexes. Based on a conception that there should be no significant difference between the coal temperatures determined by different coal spontaneous combustion indexes with sufficient accuracy, an approach for evaluating the coal spontaneous combustion index by statistical analysis was developed. After mining data screening by the coefficient of variation (Cv), the arrays of coal temperature determined by different indexes were calculated with the curve fitting. The Kruskal-Wallis test was employed to analyze the differences between the arrays of coal temperature. Finally, the weighted grey relational analysis method was used to optimize the coal spontaneous combustion indexes. The results show that the production of gaseous compounds is positively correlated with coal temperature. In this case, O2/CO2 and CO2/CO were selected as the primary indexes, and CO/CH4 was used as the alternative index of coal at low-temperature stage (≤ 80 °C). The detecting of C2H4 and C2H6 were the confirmation indexes when the coal temperature reaches 90 °C ~ 100 °C. It could provide a reference to the determination of grading index of coal spontaneous combustion during mining and utilization.
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Affiliation(s)
- Kai Wang
- College of Safety Science and Engineering, Xi'an University of Science and Technology, Xi'an, 710054, China.
- Shaanxi Key Laboratory of Prevention and Control of Coal Fire, Xi'an, 710054, China.
| | - Yang Li
- College of Safety Science and Engineering, Xi'an University of Science and Technology, Xi'an, 710054, China
- Shaanxi Key Laboratory of Prevention and Control of Coal Fire, Xi'an, 710054, China
| | - Xiaowei Zhai
- College of Safety Science and Engineering, Xi'an University of Science and Technology, Xi'an, 710054, China
- Shaanxi Key Laboratory of Prevention and Control of Coal Fire, Xi'an, 710054, China
| | - Guangxing Bai
- College of Safety Science and Engineering, Xi'an University of Science and Technology, Xi'an, 710054, China
- Shaanxi Key Laboratory of Prevention and Control of Coal Fire, Xi'an, 710054, China
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Wang F, Tan B, Chen Y, Fang X, Jia G, Wang H, Cheng G, Shao Z. A visual knowledge map analysis of mine fire research based on CiteSpace. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:77609-77624. [PMID: 35680744 DOI: 10.1007/s11356-022-20993-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 05/17/2022] [Indexed: 06/15/2023]
Abstract
Mine fire has always been a serious disaster in coal industry; many academic achievements have poured out in the past two decades for solving this problem. In this study, visual analysis was conducted to grasp the hotspots and development trend of mine fire research. Papers that published in 1999-2020 were retrieved as the data basis from Web of Science, and CiteSpace was used to carry out knowledge map analysis. The results shown that number of papers has increased steadily since 2005 and achieved explosive growth since 2014. Deng J is the first published author among many scholars. China, the USA, and Australia are active areas in mine fire research and China University of Mining and Technology ranks first in this field. The highest co-occurrence frequency keyword is "spontaneous combustion." International Journal of Coal Geology and Fuel provide guidance for mine fire research. Fire prevention technology, low carbon, ecology, and sustainable development are the hot research in recent years. The prevention and control of mine fire from combustion mechanism should be further strengthened.
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Affiliation(s)
- Feiran Wang
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Bo Tan
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China.
| | - Yue Chen
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Xiyang Fang
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Guowei Jia
- The Administrative Center for China's Agenda 21, Beijing, 100036, China
| | - Haiyan Wang
- School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Gang Cheng
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Zhuangzhuang Shao
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
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10
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Zhang S, Sun L, Qin B, Wang H, Qi G. Characteristics and main factors of foam flow in broken rock mass in coal mine goaf. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:47095-47108. [PMID: 35175523 DOI: 10.1007/s11356-022-19208-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/09/2022] [Indexed: 06/14/2023]
Abstract
To protect the environment and reduce the occurrence of coal mine fire, foam injection in goafs is an effective measure for preventing and extinguishing mine fires. The flow characteristics of foams injected into goafs have a significant impact on the prevention and extinguishment of such fires. To study the flow characteristics of foam injected into a goaf, we first independently constructed a set of experimental platforms for the visualization of goafs. Next, we performed physical experiments on foam injection using similarity theory. Flow characteristics were simulated under different foam concentrations, flow rates, and goaf porosities. The exponential function was found to provide a good fit to the trajectory of the foam's stacking edge in the goaf. According to the foam injection volume, the trend of the fitting equation parameter a could be divided into two stages. The first stage was the rapidly decreasing stage, and the second stage was the stable stage. It was inferred that the stacking height and diffusion radius of the foam under different conditions were related to the speed of liquid film drainage. The results of this study can provide a valuable reference for the use of fire prevention and extinguishment technology in the goaf.
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Affiliation(s)
- Shuaihu Zhang
- College of Safety and Environment Engineering, Shandong University of Science and Technology, Qingdao, 266590, People's Republic of China
| | - Lulu Sun
- College of Safety and Environment Engineering, Shandong University of Science and Technology, Qingdao, 266590, People's Republic of China.
- State Key Laboratory of Mining Disaster Prevention and Control Co-Founded By Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao, 266590, People's Republic of China.
- School of Safety Engineering, China University of Mining and Technology, Xuzhou, 221116, Jiangsu, People's Republic of China.
| | - Botao Qin
- School of Safety Engineering, China University of Mining and Technology, Xuzhou, 221116, Jiangsu, People's Republic of China
| | - Haishan Wang
- College of Safety and Environment Engineering, Shandong University of Science and Technology, Qingdao, 266590, People's Republic of China
| | - Guansheng Qi
- College of Safety and Environment Engineering, Shandong University of Science and Technology, Qingdao, 266590, People's Republic of China
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Li P, Sun Q, Hu J, Jia H, Xue L. Effect of the pore structure of granite and gabbro after heat treatment on the radon emission rate. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:36801-36813. [PMID: 35064488 DOI: 10.1007/s11356-021-18152-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 12/13/2021] [Indexed: 06/14/2023]
Abstract
The pore structure of rock changes significantly during the heat treatment process, which affects the internal emission rate of radon. This study introduces the results of radon emission rate of rock after high temperature and analyzes the effect of the pore structure in rock mass on radon emission. The results show that there is a good positive correlation between temperature and radon emission in rock mass within a certain temperature range, and the higher the temperature, the higher the radon concentration emission. Two igneous rocks have the rate which is highest after the treatment in 400 °C. The absorption and sealing of radon in the microcapillary are the main occurrences of radon in rock mass. This is reflected in the increase in microcapillary porosity and the decrease in DP, which changes the microstructure of the rock and increases the connectivity of the internal pore channels of the rock, thereby increasing the volume and length of the migration channels for radon. These results are helpful to understand the influencing mechanism of radon emission process in rocks.
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Affiliation(s)
- Pengfei Li
- College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, 710054, Shaanxi, China.
| | - Qiang Sun
- College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, 710054, Shaanxi, China
- Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi'an, 710054, China
- Key Laboratory of Coal Resources Exploration and Comprehensive Utilization, Ministry of Land and Resources, Xi'an, China
| | - Jianjun Hu
- College of Water Resource and Hydropower, Sichuan University, Chengdu, 610065, Sichuan, China
| | - Hailiang Jia
- College of Architecture and Civil Engineering, Xi'an University of Science and Technology, Xi'an, 710054, Shaanxi, China
| | - Lei Xue
- Innovation Academy for Earth Science, Chinese Academy of Sciences, Beijing, 100029, China
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12
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Tan B, Li X, Zhang X, Zhang Z, Zhang H. Research on Initial Prevention of Spontaneous Combustion in Coal Bunkers Based on Fire-Extinguishing and Fireproof Inerting. ACS OMEGA 2022; 7:3359-3368. [PMID: 35128246 PMCID: PMC8811917 DOI: 10.1021/acsomega.1c05528] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/30/2021] [Indexed: 06/07/2023]
Abstract
Coal bunkers are relatively closed systems. Due to their own oxidation characteristics and the increase of temperature, spontaneous combustion will occur beyond the spontaneous combustion period. Moreover, spontaneous combustion of coal bunkers is a disaster caused by multifield coupling, so it is imperative to carry out inerting fire prevention and fire extinguishing. Based on this fact, combined with the actual situation in Huanghua Port, this paper establishes a two-dimensional geometric model of a coal bunker, selects CO2 as the inert gas sprayed in the coal bunker, determines the position of the inert gas port of the coal bunker hopper, and studies the influence of fireproof and fire-extinguishing inerting on coal bunker inerting. The results show that the arrangement of the inert gas port of the bunker hopper outside the bunker is more conducive to the diffusion of CO2 gas in the bunker. In about 35-41 days, the inerting temperature decreases slowly between 345 and 350 K. After 41 days, the maximum temperature of the coal bunker decreases rapidly and the spontaneous combustion of the coal bunker is completely controlled. Under the preset conditions, the best fire inerting time is 32.3 days after coal storage.
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Affiliation(s)
- Bo Tan
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China
| | - Xiaomeng Li
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China
| | - Xuedong Zhang
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China
| | - Zhaolun Zhang
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China
| | - Heyu Zhang
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China
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13
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Li P, Sun Q, Tang S, Li D, Yang T. Effect of heat treatment on the emission rate of radon from red sandstone. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:62174-62184. [PMID: 34185268 DOI: 10.1007/s11356-021-15079-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 06/18/2021] [Indexed: 06/13/2023]
Abstract
High temperature and pore structure are important factors affecting the emission rate of radon in rocks. This study mainly focused on the correlation between radon emission rate and temperature in red sandstone. The results showed that in the temperature range of 25-400 °C, as the temperature increased, the connectivity of the internal pores of the sample became better, resulting in a significantly increased radon emission rate. The radon emission rate at 400 °C was 2.86 times the original. To explain the changes that occurred in the internal structure of the samples, the porosity characteristics of the samples after heat treatment were studied by nuclear magnetic resonance (NMR). It was found that the pore structure was also an important factor affecting the rate of radon emission. The smaller pore size of the micropores (r < 0.1 μm) inhibited the emission of radon in the sandstone. These results helped in understanding the mechanism of radon emission rate and provide an important basis for predicting rock fragmentation and coal fire.
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Affiliation(s)
- Pengfei Li
- College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, 710054, Shaanxi, China.
| | - Qiang Sun
- Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi'an, 710054, China.
- Key Laboratory of Coal Resources Exploration and Comprehensive Utilization, Ministry of Land and Resources, Xi'an, China.
| | - Shengli Tang
- College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, 710054, Shaanxi, China
| | - Delu Li
- College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, 710054, Shaanxi, China
| | - Tian Yang
- College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, 710054, Shaanxi, China
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14
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Deng J, Ge S, Qi H, Zhou F, Shi B. Underground coal fire emission of spontaneous combustion, Sandaoba coalfield in Xinjiang, China: Investigation and analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 777:146080. [PMID: 33677308 DOI: 10.1016/j.scitotenv.2021.146080] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Revised: 02/19/2021] [Accepted: 02/19/2021] [Indexed: 06/12/2023]
Abstract
Long-term spontaneous combustion of coal has caused serious ecological and environmental problems. Only in recent years has it received growing popularity to undertake relevant researches. In order to study the impact of combustion by-products on atmosphere in the Sandaoba fire field, Xinjiang, a region-scale field survey was firstly conducted to investigate the gaseous-solid emissions in separated fire sections. The evaluation method and model have been proposed to describe the underground combustion and the related air pollution. Every year, the total estimates of the gaseous emission are approximately 4030 t of CO2, 113.6 t of SO2 and 57.3 t of CO. The emission pollution varies considerably from regions, and is substantially attenuated with the advancement of fire control. Principal component analysis (PCA) refines the thermophysical parameters into three attributions: the intrinsic thermophysical property, atmospheric dynamics, and combustion degree. PCA score distribution shows that thermophysical parameter is dominated by the combustion condition at severely polluted areas. Factor Analysis is used to extract four contaminant indicators, which suggests the local air suffers sulfur oxides pollution the most. The air quality index of the eight study sections calculated are all below 60, ranging from 24 to 58. It indicates that coal fire air pollution is in the medium-to-severe stage. By Canonical Correlation Analysis, it is noted that thermophysical indicator performs outstanding explanatory for contaminant variates. On the whole, the higher the level of thermophysical properties in the fire area, the greater the intensity of pollutant emission. Underground coalfield fire is dominated by smoldering, and the overall combustion efficiency is lower than 0.8 which generally declines as the excess air coefficient increasing.
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Affiliation(s)
- Jinchang Deng
- Jiangsu Key Laboratory of Fire Safety in Urban Underground Space, China University of Mining and Technology, Xuzhou 221116, China
| | - Shaokun Ge
- Jiangsu Key Laboratory of Fire Safety in Urban Underground Space, China University of Mining and Technology, Xuzhou 221116, China
| | - Haining Qi
- Jiangsu Key Laboratory of Fire Safety in Urban Underground Space, China University of Mining and Technology, Xuzhou 221116, China
| | - Fubao Zhou
- Jiangsu Key Laboratory of Fire Safety in Urban Underground Space, China University of Mining and Technology, Xuzhou 221116, China; Key Laboratory of Gas and Fire Control for Coal Mines, China University of Mining and Technology, Ministry of Education, Xuzhou 221116, China; School of Safety Engineering, China University of Mining and Technology, Xuzhou 221116, China.
| | - Bobo Shi
- Jiangsu Key Laboratory of Fire Safety in Urban Underground Space, China University of Mining and Technology, Xuzhou 221116, China; Key Laboratory of Gas and Fire Control for Coal Mines, China University of Mining and Technology, Ministry of Education, Xuzhou 221116, China; School of Safety Engineering, China University of Mining and Technology, Xuzhou 221116, China
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15
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Zhu H, Huo Y, He X, Wang W, Fang S, Zhang Y. Molecular model construction of Danhou lignite and study on adsorption of CH 4 by oxygen functional groups. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:25368-25381. [PMID: 33454865 DOI: 10.1007/s11356-021-12399-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 01/05/2021] [Indexed: 05/27/2023]
Abstract
In view of the frequent occurrence of gas accidents in coal mines, the mechanism of oxygen-containing functional groups (OCFGs) in Danhou lignite adsorbing gas was studied by experiment and simulation. Elemental analysis, X-ray photoelectron spectroscopy (XPS), solid-state 13C nuclear magnetic resonance spectroscopy (13C-NMR), and adsorption experiment of CH4 were applied to establish the macromolecular model of Danhou lignite. Then, molecular mechanics (MM) and molecular dynamics (MD) were utilized to optimize the coal macromolecular model, and the density of coal was determined via adding periodic boundary conditions. The mechanism of gas adsorption by OCFGs was studied by grand canonical Monte Carlo (GCMC) and density functional theory (DFT). The results showed that the aromatic structures mostly exist in the form of pyrenes; the structure of aliphatic carbons are mostly methylene and methine groups; the alkanes are mostly long chains; oxygen atoms are mainly in the form of hydroxyl groups and ether groups; nitrogen atoms are mainly in the form of pyridines; and the density of Danhou lignite is 1.25 g/cm3. The isotherm adsorption curve and Langmuir adsorption curve have a good fit, a single coal molecule reaches saturation after absorbing four CH4 molecules, and the error between experiment and simulation is small. The results of DFT calculation showed that the adsorption of CH4 by OCFGs is affected by the adsorption positions and adsorption directions. Due to CH4 molecules are affected by different electrostatic forces, the adsorption capacities of OCFGs are different, and the order is carbonyl groups > ether bonds > hydroxyl groups > carboxyl groups. The results can be used for reference in the prevention and control of coal and gas outburst.
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Affiliation(s)
- Hongqing Zhu
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), No. ding 11 College Road, Haidian District, Beijing, 100083, China
| | - Yujia Huo
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), No. ding 11 College Road, Haidian District, Beijing, 100083, China.
| | - Xin He
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), No. ding 11 College Road, Haidian District, Beijing, 100083, China
| | - Wei Wang
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), No. ding 11 College Road, Haidian District, Beijing, 100083, China
| | - Shuhao Fang
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), No. ding 11 College Road, Haidian District, Beijing, 100083, China
| | - Yilong Zhang
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), No. ding 11 College Road, Haidian District, Beijing, 100083, China
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16
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Hong X, Yang K, Liang H. Characterization of acidity and sulfate in dust obtained from the Wuda coal base, northern China: spatial distribution and pollution assessment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:10.1007/s11356-021-12897-8. [PMID: 33634406 DOI: 10.1007/s11356-021-12897-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 02/08/2021] [Indexed: 06/12/2023]
Abstract
The coal fire in Wuda, Inner Mongolia of China, is one of the most serious coal fires in the world with a history over 50 years and endangers the neighboring downwind urban area. A lack of effective measures to control coal fires in this region can aggravate environmental pollution. In this study, the levels and spatial distributions of acid (pH) and SO42- in dust in the Wuda coalfield and its surrounding areas in Inner Mongolia, North China, were reported to identify the potential acid and SO42- pollution in the local environment with an area of 270 km2. The mean pH and SO42- content was to found to be 7.44 and 5981 μg·g-1, respectively. Through the analysis of the spatial distribution of pH and SO42- concentrations, it was found that most of contaminated areas are mainly distributed in coalfield and its affiliated industrial parks, and the Wuda urban area also suffered from pollution. Based on chemical equilibrium, the surface acid pollution might have resulted in the change of the dust type from the original weakly alkaline CaCO3 type to the CaSO4 type in coalfield and industrial parks. Finally, the pollution assessment revealed that the coalfield and industrial parks are both at heavy pollution levels, and the urban area is mostly moderately polluted, followed by farm and peripheral region with a certain pollution risk. The results indicated that the long-term release of acidic gas from the coal fires and industrial parks can led to significantly elevated acidity and SO42- levels in the dust of the local environment, while coal fires can aggravate surface pollution in industrial parks, but the extent of contamination was also closely related to the terrain and wind direction in the study area.
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Affiliation(s)
- Xiuping Hong
- College of Life Science, Huaibei Normal University, Huaibei, 235000, China.
| | - Kang Yang
- School of Chemical & Environmental Engineering, China University of Mining and Technology, Beijing, 100083, China
| | - Handong Liang
- State Key Laboratory of Coal Resources and Safety Mining, China University of Mining and Technology, Beijing, 100083, China.
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17
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Wang H, Tan B, Zhang X. Research on the technology of detection and risk assessment of fire areas in gangue hills. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:38776-38787. [PMID: 32632694 DOI: 10.1007/s11356-020-09847-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/22/2020] [Indexed: 06/11/2023]
Abstract
Coal gangue hills are prone to spontaneous combustion, thereby polluting the environment of mining areas such as the soil, groundwater, and atmosphere, and the frequent occurrence of gangue hill collapses, landslides, explosions, and other accidents can even endanger the lives and property of residents. To realize the safety management of coal gangue spontaneous combustion and evaluate its present risks, this paper selects the Dongzhou Kiln gangue hill in Zuoyun County, Datong City, China, as the research object to conduct a risk assessment study. The Dongzhou gangue hill fire area is relatively large, with a total area of 183,039 m2. Smoke emission commonly occurs at the site, and the surface temperature reaches 50 °C, while the CO concentration exceeds 10-3. A radon detection scheme for concealed fire zones verified with borehole temperature measurements is applied. The high-temperature area is delineated with relevant data obtained by infrared thermal imaging, radon concentration, and borehole temperature detection technologies, and a coal gangue spontaneous combustion risk assessment method is established, while the gas toxicity and explosion risks of the construction area and fire trends are analyzed. The research results indicate that there are 6 likely high-temperature regions in the test area, 4 high-toxicity areas in the drilling construction area, 1 area with a high explosion risk, and 3 areas with a high risk of spontaneous combustion. Among these areas, platform 2 is a high-risk area and needs to be carefully considered. The construction of the entire area is at high risk, including toxicity, gas explosion, and spontaneous combustion risks, and measures must be implemented to reduce the overall risk.
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Affiliation(s)
- Haiyan Wang
- Faculty of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, China
- China Coal Research Institute, Beijing, China
| | - Bo Tan
- Faculty of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, China.
| | - Xuedong Zhang
- Faculty of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, China
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Experimental Study on the Physisorption Characteristics of O 2 in Coal Powder are Effected by Coal Nanopore Structure. Sci Rep 2020; 10:6946. [PMID: 32332828 PMCID: PMC7181757 DOI: 10.1038/s41598-020-63988-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Accepted: 04/06/2020] [Indexed: 11/25/2022] Open
Abstract
Coal is a porous medium. Oxygen molecules in the air penetrate through the pores of coal and are adsorbed on the coal surface. Low-temperature oxidation of coal then occurs, by which coal spontaneous combustion is promoted. Given this process, the authors analysed the physisorption characteristics of O2 in pulverized coal from the perspective of nanopore structure. In this study, five different kinds of coal samples (two lignites, one bituminous coal, and two anthracites) were selected, and the surface morphology, pore structure parameters and oxygen physisorption capacity of the pulverized coals were determined by scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP) and oxygen adsorption with chromatography (OAC), respectively. The experimental results of SEM and MIP show that with the development of coal, the surface folds increase, and the pores increase in number and shrink, which leads to the nanopores of anthracite and bituminous coal being smaller and more complex than those of lignite. The experimental results of OAC show that adsorbed oxygen is physisorbed by pulverized coal in the order lignite > bituminous coal > anthracite. Analysis of the oxygen desorption curves shows that the oxygen desorption rates of the anthracites and bituminous coal are slower than those of the lignites. The results show that the amount of oxygen physisorbed by pulverized coal is proportional to the fractal dimension of the coal pores, proportional to the pore volume of the nanoscale pores, and inversely proportional to the number of closed pores in the coal. Based on the results of the analyses mentioned above, it is important to analyse the process of coal-oxygen chemisorption and the mechanism for low-temperature oxidation of coal to prevent coal spontaneous combustion.
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Tan B, Shao Z, Wei H, Yang G, Zhu X, Xu B, Zhang F. Status of research on hydrogen sulphide gas in Chinese mines. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:2502-2521. [PMID: 31858415 DOI: 10.1007/s11356-019-07058-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 11/13/2019] [Indexed: 06/10/2023]
Abstract
In the process of coal mining, the abnormal gushing of hydrogen sulphide in mines poses a major threat to the health of coal miners and the safe production of mines, as these types of accidents have occurred in many coal-producing countries. China is the largest coal producer and consumer in the world and is one of the countries that are substantially affected by hydrogen sulphide in mines. Based on the existing studies, many investigators in China have conducted research on the actual situation in China and obtained some results. This paper summarizes the previous findings and the current status of hydrogen sulphide in Chinese mines, and predicts the direction of future development. In this paper, we discuss the cause, abnormal distribution, abnormal gushing and prevention and control measures for hydrogen sulphide in mines. In addition, this paper also evaluates the impact of the hydrogen sulphide in mines on the environment and health. This paper outlines a systematic research framework regarding hydrogen sulphide in mines and assesses the interrelationship between subtopics within this system framework. Currently, the scientific research on hydrogen sulphide in mines is not sufficient to meet the needs of the affected individuals Therefore, researchers must increase their efforts in this area to jointly address the challenge of analysing hydrogen sulphide in mines. In addition, we hope that this paper will provide some guidance for the study of hydrogen sulphide in mines.
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Affiliation(s)
- Bo Tan
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Zhuangzhuang Shao
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Hongyi Wei
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Guangyuan Yang
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Xiaoman Zhu
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Bin Xu
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China
| | - Feichao Zhang
- School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China.
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