Thermogravimetric and infrared spectral analysis of candle coal pyrolysis under low-oxygen concentration

Chen, Liangzhou; Qi, Xuyao; Yang, Jian; Xin, Haihui

doi:10.1016/j.tca.2020.178840

Cited by 22 publications

(2 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…When the constant temperature reaches 450 • C, the consumption of combustible substances increases, and the mass of the coal samples finally decreases by 80% in low oxygen combustion reaction, because the interior of coal samples is changed greatly, and the reactants increase. In order to better characterize the experimental process and quantitatively describe the pyrolysis and low oxygen combustion characteristics, relevant characteristic parameters were used for characterization [42,43]. The relevant parameters include: initial separation residue of volatile components weight, Wv%, indicating the mass fraction of combustible substances in coal samples.…”

Section: Characteristics Of Coal Pyrolysis and Low Oxygen Combustionmentioning

confidence: 99%

Characteristics of Pyrolysis and Low Oxygen Combustion of Long Flame Coal and Reburning of Residues

et al. 2021

Self Cite

View full text Add to dashboard Cite

To further understand the problems of coal combustion and coalfield fire reignition, this paper researched the reaction characteristics of coal pyrolysis and low oxygen combustion and the reburning oxidation characteristics of residual structure by thermal analysis methods. The results show that temperature promotes both pyrolysis and low oxygen combustion reactions, but low oxygen combustion reaction is more sensitive to temperature changes. As the constant temperature rises, the mass reduction rate of low oxygen combustion of coal samples reaches 80% on average, which is 4 times that of pyrolysis, and the variations of thermogravimetric parameters are also significantly higher than those of pyrolysis. However, the higher the pyrolysis degree of the residues, the stronger their oxidizability, which greatly enhances the intensity and concentration of the secondary combustion, and the mass of residues is reduced by 90% on average. Conversely, because the combustible components are continuously consumed during low oxygen combustion, the reburning characteristics of residues become less obvious. For instance, the weight loss rate slows down, the burning becomes dispersed, and the burning intensity is weakened. In addition, the heat release is reduced from 8662 to 444.5 J/g, and the change trend is just opposite to that of pyrolysis. The above results show that as the constant temperature rises, the pyrolysis reaction greatly shortens the reburning process, while the low oxygen combustion reaction largely inhibits the reburning.

show abstract

Section: Characteristics Of Coal Pyrolysis and Low Oxygen Combustionmentioning

confidence: 99%

Characteristics of Pyrolysis and Low Oxygen Combustion of Long Flame Coal and Reburning of Residues

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…Coal self-heating is essentially the physical and chemical reactions between coal and oxygen, − which indicate that coal self-heating and oxygen concentration distribution in goaf are closely related. − It is reported that when the oxygen concentration in goaf is within a certain critical range, coal spontaneous combustion will be easily triggered. − Tutak et al investigated the connection between goaf formed by different types of roof rocks and the high-risk zone of coal self-heating in the Y-type ventilation system. It indicates that the caving rock leads to the different distribution of goaf permeability as well as the range of coal oxidation zone.…”

Section: Introductionmentioning

confidence: 99%

Coupling Relation between the Location of Cross-Cut Negative Pressure and Injecting Nitrogen into Coal Mine Goaf

Chen

et al. 2021

ACS Omega

Self Cite

View full text Add to dashboard Cite

Injecting nitrogen into goaf has been widely adopted for preventing fire hazards in coal mines. In this paper, the coupling relation between different locations of negative pressure of cross-cut drainage and nitrogen injection was investigated. The minefield data collection was carried out by an in situ beam tube system on the intake airway and return airway of the mine goaf. The validated Computational Fluid Dynamics (CFD) model that was secondarily modified by on-site collected data was applied for further research. It is demonstrated that the area of the spontaneous combustion zone generally shows a sharp decline first, then tends to stabilize, and finally has a slight drop and rise with the increasing nitrogen injection time. It is obvious that the location of the negative pressure of cross-cut exerts a significant influence on the optimal nitrogen injection location and time. When the cross-cut is located in the center of the air leakage zone, spontaneous combustion zone, and asphyxiation zone of goaf, the optimal nitrogen injection location and time correspond to the P2 (25 m, 1200 min), P3 (30 m, 120 min), and P4 (35m, 1800 min), respectively. According to the simulation result, the specific relation between the optimal nitrogen injection point N(x) and the distance from the working distance of the cross-cut (x) by Newton interpolation polynomial analysis was figured out and verified that N(x) = 24.70808 + 0.293356x – 0.001436x 2. It is hoped that the result can provide scientific guidance for coal mine fire prevention and control with nitrogen injection.

show abstract

Investigation on oxygen-controlled sewage sludge carbonization with low temperature: from thermal behavior to three-phase product properties

et al. 2022

Environ Sci Pollut Res

View full text Add to dashboard Cite

Thermogravimetric and infrared spectral analysis of candle coal pyrolysis under low-oxygen concentration

Cited by 22 publications

References 46 publications

Characteristics of Pyrolysis and Low Oxygen Combustion of Long Flame Coal and Reburning of Residues

Characteristics of Pyrolysis and Low Oxygen Combustion of Long Flame Coal and Reburning of Residues

Coupling Relation between the Location of Cross-Cut Negative Pressure and Injecting Nitrogen into Coal Mine Goaf

Investigation on oxygen-controlled sewage sludge carbonization with low temperature: from thermal behavior to three-phase product properties

Contact Info

Product

Resources

About