Hu Shi, Wei Cai, Xin Wang^*, Lei Song, Yuan Hu^*

Journal of Renewable Materials, Vol.11, No.12, pp. 3991-4006, 2023, DOI:10.32604/jrm.2023.029888

Abstract To solve the fire accidents caused by coal combustion, this work prepared four hybrid hydrogel materials using bio-based polymers, flame retardants, and inorganic materials. Compared to pure water and 3.5 wt% MgCl₂ solution, the as-prepared hydrogel presents good fire prevention performance. In addition, it is found that CO and CO₂ are not produced by coal when the pyrolysis temperature is lower than 200°C. During low-temperature pyrolysis, CO is more likely to be produced than CO₂, indicating inadequate pyrolysis behavior. At the same time, the addition of fire-preventing hydrogel can not only decrease the maximum CO₂ concentration before the critical temperature… More > Graphic Abstract

Haitao Wang^1,2, Yongli Liu^1,*, Bin Shen¹, Mengxuan Ren¹, Qiyuan Shan¹

Energy Engineering, Vol.119, No.5, pp. 2031-2047, 2022, DOI:10.32604/ee.2022.020776

Abstract The goal of this study was to investigate coal quality features and their relationship to coal spontaneous combustion characteristics in multi-seam coal mines to better predict when coal spontaneous combustion is likely to occur. To that end, coal samples of various particle sizes were obtained from five coal seams (Nos. 6, 8, 9, 12 and 20) in the Shuangyashan City Xin’an Coal Mine. The samples were then respectively heated using a temperature programming system to observe and compare similarities and differences in the spontaneous combustion process of different particle sizes in response to rising temperature. The experimental results show, that… More >

Ang Li^1,2, Peng Lei^1,*, Changkun Chen¹, Tong Xu¹

Energy Engineering, Vol.118, No.5, pp. 1469-1482, 2021, DOI:10.32604/EE.2021.015413

Abstract A simplified model for SO₂ generation during spontaneous combustion of coal gangue was put forward and validated using the measured data. Using the proposed model, the effects of initial temperature inside the gangue and fresh air supply on SO₂ generation were discussed. The results showed that, higher initial temperature inside the gangue could accelerate the oxidation rate of FeS₂ and increase the maximum concentration of SO₂. If initial temperature inside the gangue increased by about 37%, the total SO₂ generation increased by 166%. Fresh air supply had less significant effect on the oxidation rate of FeS₂. However, the higher the… More >

Xuying Guo^1,2,*, Saiou Fu¹, Junzhen Di³, Yanrong Dong³, Guoliang Jiang³

Journal of Renewable Materials, Vol.9, No.3, pp. 541-555, 2021, DOI:10.32604/jrm.2021.012335

Abstract The high concentrations of Fe²⁺ and Mn²⁺ in acid mine drainage make it difficult and expensive to treat. It is urgent that we find a cheap and efficient adsorption material to treat Fe²⁺ and Mn²⁺. As a solid waste in mining areas, coal gangue occupies a large area and pollutes the surrounding environment during the stacking process. Developing a method of resource utilization is thus a research hotspot. In this study, we modified spontaneous combustion gangue using NaOH, NaCl, and HCl by chemically modifying the minerals. We determined the optimal conditions for treating Fe²⁺ and Mn²⁺ in acid mine drainage… More >