Three-dimensional distribution and oxidation degree analysis of coal gangue dump fire area: A case study

Haiyan Wang; Xiyang Fang; Feng Du; Bo Tan; Lang Zhang; Yanchuan Li; Changfu Xu

doi:10.1016/j.scitotenv.2021.145606

Three-dimensional distribution and oxidation degree analysis of coal gangue dump fire area: A case study

Sci Total Environ. 2021 Jun 10:772:145606. doi: 10.1016/j.scitotenv.2021.145606. Epub 2021 Feb 4.

Authors

Haiyan Wang¹, Xiyang Fang², Feng Du³, Bo Tan⁴, Lang Zhang⁵, Yanchuan Li⁶, Changfu Xu⁵

Affiliations

¹ China Coal Research Institute, Beijing 100013, China.
² China Coal Research Institute, Beijing 100013, China; Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources, China University of Mining and Technology, Beijing 100083, China; School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China. Electronic address: Tepp_123@163.com.
³ Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources, China University of Mining and Technology, Beijing 100083, China; School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China; State Key Laboratory Cultivation Base for Gas Geology and Gas Control, Henan Polytechnic University, Jiaozuo 454000, China. Electronic address: fengducumtb@126.com.
⁴ Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources, China University of Mining and Technology, Beijing 100083, China; School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China.
⁵ Mine Safety Technology Branch of China Coal Research Institute, Beijing 100083, China; State Key Laboratory of the Ministry of Education of China for High-efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 100083, China.
⁶ China Coal Research Institute, Beijing 100013, China; Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources, China University of Mining and Technology, Beijing 100083, China.

PMID: 33770898
DOI: 10.1016/j.scitotenv.2021.145606

Abstract

Spontaneous combustion of coal gangue dumps poses a significant threat to the health and safety of nearby residents and has adverse effects on the environment. The establishment of measures to extinguish these fires requires information on the three-dimensional characteristics and oxidation degree of the dumps. An acquisition method for the index data was proposed. The temperature and the radon concentration were used as the principal indicators, and the gas concentration was a secondary index for verifying the results. Kriging interpolation was applied to predict the value of the unsampled points. Additionally, the three-dimensional characteristics of the temperature and radon anomalies were determined, thresholds were set, and the changes in the temperature and radon migration were considered to estimate the extent and depth of the fire in the coal gangue dumps. The oxidation degree of the anomalous area was identified according to the critical value of the temperature and radon anomalies. The application of this method in the gangue dump of the Tashan coal mine showed the existence of 17 oxidation areas, covering an area of 31,433 m², including 4 shallow oxidation areas, 4 deep oxidation areas in coal waste dumps, and 9 medium-deep oxidation areas. According to the decision criterion, 4 areas with relatively high oxidation degree were identified, whereas the remaining sites were low-oxidation areas. Additionally, surface fires and internal fires can be transformed into each other, posing a significant threat. The results obtained from the various data sources were consistent and in agreement with the ground survey results, indicating that the proposed method is effective for the detection of fires in coal gangue dumps.

Keywords: Coal gangue dump; Depth index; Fire detection; Kriging method; Oxidation degree.