Insight into the chemical reaction process of coal during the spontaneous combustion latency

Líu, Hao; Li, Zenghua; Miao, Guodong; Yang, Jingjing; Wu, Xiangqiang; Li, Jiahui

doi:10.1016/j.energy.2022.125823

Cited by 28 publications

(5 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At R70, water began to evaporate, and the active sites covered by water began to appear. The evaporation of water not only leads to the exposure of the active center but also exposes the pores and fissures of the coal surface reacting with oxygen. , At this time, it can be seen from the infrared spectrum experiment, the addition of an inhibitor makes the content of oxygen-containing functional groups with higher activity decrease, reduces the oxidation of its active sites, delays the oxidation process of coal, blocks the reciprocal transformation path between the active center and the oxidized functional group, and also promotes the formation of relatively stable inert oxygen-containing ether bonds, thereby inhibiting the spontaneous combustion of coal.…”

Section: Resultsmentioning

confidence: 99%

Experimental Study on the Inhibition Effect of the Inhibitor on Coal Spontaneous Combustion Under Critical Temperature

Zhang,

Zou,

et al. 2024

ACS Omega

View full text Add to dashboard Cite

At present, related research on inhibitors has been gradually improved, but there is still a lack of research on the inhibition characteristics at specific release temperatures and the mechanism of inhibiting coal spontaneous combustion. Based on this, In this study, the inhibition characteristics of adding inhibitor to coal under critical temperature (R70) are studied in depth. In the experiment, lignite was selected as the research object, and four different types of inhibitors, MgCl 2 , triphenyl phosphite (TPPI), Phytic acid (PA), and melatonin, were applied to coal samples at room temperature and 70 °C, respectively. The temperatureprogrammed-gas chromatography test and Fourier infrared spectroscopy experiment were carried out, and the oxidation kinetic parameters were calculated to study the oxidation characteristics and micromechanism of the coal samples in the process of spontaneous combustion. The experimental results show that the amount of CO gas release and oxygen consumption rate are lower, and the inhibition rate and apparent activation energy are higher when the inhibitor is added under R70 than at room temperature. Under R70, the content of oxygen-containing functional group −COOH with higher activity of inhibitor is reduced, the generation of active sites is inhibited, the concentration of active center is reduced, the path of mutual transformation between active sites and oxygen-containing functional groups is blocked, and the active groups are promoted to form a relatively stable inert oxygencontaining ether bond, which reduces the spontaneous combustion tendency of coal.

show abstract

Section: Resultsmentioning

confidence: 99%

Experimental Study on the Inhibition Effect of the Inhibitor on Coal Spontaneous Combustion Under Critical Temperature

Zhang,

Zou,

et al. 2024

ACS Omega

View full text Add to dashboard Cite

show abstract

“…where k 1 and k 2 are designed positive constants, m 1 and n 1 are positive odd constants and m 1 /n 1 < 1. Substituting Equations ( 16) and ( 18)- (20) into Equation ( 15), we obtain…”

Section: ŵ1mentioning

confidence: 99%

“…In some practical engineering systems, for example, the chemical reaction process [20] and the attitude control of spacecraft [21], stability typically needs to be achieved within a finite time. However, many control methods can only obtain stability of control systems within an infinite time [22][23][24].…”

Section: Introductionmentioning

confidence: 99%

Position and Attitude Tracking Finite-Time Adaptive Control for a VTOL Aircraft using Global Fast Terminal Sliding Mode Control

Deng

Huang

et al. 2023

Mathematics

View full text Add to dashboard Cite

In this work, the position and attitude tracking finite-time adaptive control problem of a type of vertical take-off and landing (VTOL) aircraft system is studied. Here, the dynamic of the VTOL aircraft is subjected to external disturbances and unknown nonlinearities. Firstly, radial basis function neural networks are introduced to approximate these unknown nonlinearities, and adaptive weight update laws are proposed to replace unknown ideal weights. Secondly, for the errors generated in the approximation process and the external disturbances of the aircraft system, adaptive parameter update laws are presented. After that, based on the designed global fast terminal sliding mode control functions and adaptive update laws, we present the position tracking control laws and the roll angle control law. Then, based on this, the adaptive global fast terminal sliding control laws for the given aircraft system are finally obtained. Meanwhile, the stability of the aircraft control system is proven by using Lyapunov stability theory and designed adaptive control laws. It is not only ensured that the outputs of the aircraft system can track the given trajectories, but also ensured that the tracking errors can converge to approximately zero within a finite time. Finally, the validity of the designed adaptive control laws is verified through three numerical examples. It can be obtained that the finite-time tracking problems of the given aircraft system can be achieved at 18.8766 s and 14.6340 s under the given parameters. The results are consistent with the theoretical analysis. In addition, under the control laws proposed in this work, the aircraft system can achieve tracking after 9.443 s and 9.674 s and the tracking errors are basically close to zero, which is significantly superior to other control methods considered in this work.

show abstract

“…However, a few studies focus on the evolution of pore and fissure structures of coal during low-temperature oxidation. − It is of great possibility that there exists a correlation between the pore and fissure structure of coal and oxidation from the macroscopic view. Based on the mainstream theory of the cause of coal spontaneous combustion (CSC), − the theory of coal–oxygen interaction, the initial stage of the coal–oxygen interaction is a physical adsorption stage, which is mainly manifested by the migration of oxygen to the internal pores of coal . Coal pores and fractures can be used as a channel for the migration and transportation of oxygen. − At the same time, oxygen may also be able to penetrate into the interior along the surface fissures of coal and induce heat accumulation from coal oxidization.…”

Section: Introductionmentioning

confidence: 99%

“… 26 − 30 It is of great possibility that there exists a correlation between the pore and fissure structure of coal and oxidation from the macroscopic view. Based on the mainstream theory of the cause of coal spontaneous combustion (CSC), 31 − 34 the theory of coal–oxygen interaction, the initial stage of the coal–oxygen interaction is a physical adsorption stage, which is mainly manifested by the migration of oxygen to the internal pores of coal. 35 Coal pores and fractures can be used as a channel for the migration and transportation of oxygen.…”

Section: Introductionmentioning

confidence: 99%

Exploring the Effect of Low-Temperature Oxidation on the Petrophysical Characteristics of Coal

Li,

Cao,

et al. 2023

ACS Omega

View full text Add to dashboard Cite

Low-temperature oxidation leads to the accumulation of heat in coal, and it is an important trigger for coal spontaneous combustion (CSC). The oxidation effects induce irreversible damage in the pore and fracture structures of coal, which provide a way for the infiltration of oxygen. In this work, the evolution of pores and cracks of coal in the progress of low-temperature oxidation is researched based on nitrogen adsorption, scanning electron microscopy (SEM), and ultrasonic testing. The results show that the oxidation effect increases microporous structures and promotes the development of mesopores and macropores in coal. Besides, as the temperature increases, the oxidation effect becomes more significant, while the pore morphology has not changed significantly yet. Meanwhile, the oxidation effect causes coal particles to block or collapse in the macropores, and the plugging degree increases with increasing temperature.

show abstract

Insight into the chemical reaction process of coal during the spontaneous combustion latency

Cited by 28 publications

References 38 publications

Experimental Study on the Inhibition Effect of the Inhibitor on Coal Spontaneous Combustion Under Critical Temperature

Experimental Study on the Inhibition Effect of the Inhibitor on Coal Spontaneous Combustion Under Critical Temperature

Position and Attitude Tracking Finite-Time Adaptive Control for a VTOL Aircraft using Global Fast Terminal Sliding Mode Control

Exploring the Effect of Low-Temperature Oxidation on the Petrophysical Characteristics of Coal

Contact Info

Product

Resources

About