Process Of Coal Spontaneous Combustion Research Articles

Investigate on spontaneous combustion characteristics of lignite stockpiles considering moisture and particle size effects

Coal spontaneous combustion (CSC) threatens the safety of the coal industry, with moisture content and particle size being pivotal factors. This study examines the heating dynamics and critical self-ignition temperatures (CSITs) of Baiyinhua lignite stockpiles through wire-mesh basket (WMB) tests at two scales. The CSC process in coal stockpiles unfolds in four stages. Notably, Stage II is notable for significant moisture evaporation between 43 and 84 °C, while Stage IV marks the onset of self-heating. Moisture evaporation absorbs heat, linearly prolonging the Stage II duration, which accounts for 0%–70 % of the total time. Conversely, larger particle sizes enhance pore seepage, effectively shortening the heating time. The time for d = 20 mm (particle size) coal sample to reach ambient temperature is roughly half that of 1.5 mm. CSITs of raw coal increase by 10–15 °C compared to the dry coal, and CSIT of coal samples with d = 50 mm has increased by 17.5 °C compared to 10 mm. Therefore, both an increase in particle size and moisture content increase the CSIT, thereby reducing the propensity for CSC. Frank-Kamenetskii theory and dimensionless analysis predict spontaneous combustion risks in field-scale coal stockpiles. This investigation contributes valuable insights to the estimation and prevention of CSC.

Development of a Graded Early Warning Index System and Identification of Critical Temperatures for Coal Spontaneous Combustion Using Composite Gas Characteristics.

Conventional single gas alarm method and coal spontaneous combustion three-stage alarm method have become increasingly inadequate to meet complex underground conditions. To address this issue, this study focuses on the coal in the goaf of the Z109 working face in the Donggucheng Mine as the research object. Through program-controlled heating experiments, the production of carbon monoxide and hydrocarbon gases during the coal oxidation process was determined, and the variation characteristics of gas ratios with temperature were further analyzed. The coal spontaneous combustion process was subdivided into seven small stages, and a quantitative composite parameter coal spontaneous combustion grading warning system was formulated. Based on its characteristics, measures to be taken under different warning levels were proposed, and it was determined that 120, 140, and 160 °C are the key temperatures for coal spontaneous combustion prevention and control in the Z109 working face of Donggucheng Mine. By using numerical simulation, the optimal nitrogen injection position for the working face was determined and the on-site fire prevention and extinguishing measures were optimized, providing insights into the establishment of a coal mine spontaneous combustion warning system.

Preparation and Experimental Research of Temperature Sensitive Expansion Gel Material for Fire Prevention and Extinguishing in Coal Mines

ABSTRACT In order to solve the problems of high viscosity at room temperature, easy dehydration and shrinkage of phase change gel, and poor plugging effect of traditional mine gel, a new type of temperature-sensitive expansion gel was developed by using hydroxypropyl methyl cellulose, chitosan, guar gum and sodium bicarbonate as raw materials, using orthogonal test and response surface analysis. The structural characterization, characteristics, fire prevention, and extinguishing performance of the temperature-sensitive expansion gel were tested. The experimental results show that the optimal ratio of temperature-sensitive swelling gel is 0.75 wt % chitosan, 0.5 wt % acetic acid, 2.5 wt % hydroxypropyl methyl cellulose, 0.4 wt % sodium bicarbonate, and 0.15 wt % guar gum. The phase transition temperature (LCST) of this ratio is 67°C. After standing at room temperature for 6 h, the gel viscosity is 5852 mpa·s, the expansion ratio is 0.846, and the strength is 319.525 N/m2. During the heating process of the coal sample after adding the temperature-sensitive expansion gel, the gel will undergo phase change and expansion in the high-temperature area of the coal, and the viscosity will increase. It can stay in the high-temperature area, wrap the coal block, and isolate the oxygen from entering, thus effectively inhibiting the coal spontaneous combustion process. In addition, the gel also produces inert gas carbon dioxide, which effectively suffocates the flame. Therefore, compared with the conventional inhibitor solution, the temperature-sensitive expansion gel has better fire extinguishing effect.

Effect of axial stress-induced coal particle breakage on the evolution laws of coal spontaneous combustion characteristics and limit parameters of loose broken coal

Coal particles are broken to varying degrees under the axial stress, thereby affecting the particle size distribution, which has an essential impact on coal spontaneous combustion (CSC). This work investigated the evolution behavior of the characteristic parameters and limit parameters of the coal oxidation process under different breakage degrees. Results showed that as the axial stress increased, the breakage degrees of coal gradually increased, while the permeability gradually declined. The increase in the breakage degree of particle induced by axial stress would promote the CSC process and increase the risk of CSC. The promotion effect reached the most prominent at 12 MPa and began to decrease at 15 MPa. Particle breakage and increasing specific surface area caused by stress were responsible for the change in CSC characteristic parameters. The reduction in permeability caused by stress dominated the changes in CSC limit parameters.

Research Progress and Development Trend of Coal Spontaneous Combustion Prevention Technology

ABSTRACT Preventing and managing spontaneous combustion of coal is essential for maintaining the steady growth of the national economy and is a prerequisite for encouraging the establishment of an ecological civilization. This study examines the mechanisms and characteristics of the CSC(coal spontaneous combustion)process, summarizes the technologies for monitoring, detection, and early warning of CSC, compares and analyzes the benefits and drawbacks of the current state of CSC prevention and control response technologies, and introduces the existing technologies for CSC retardation in terms of heat-absorbing and temperature-reducing inhibitors, oxygen-insulating inhibitors, and changing the structure of coal seams. It is pointed out that there are still problems to be solved in the mechanism of CSC formation and evolution, monitoring and early warning, and green prevention and control. Finally, it is concluded that the CSC prevention and control technology should be developed in the direction of precision, high efficiency, economy, intelligence and environmental protection.

Investigating the Influence of Flue Gas Induced by Coal Spontaneous Combustion on Methane Explosion Risk

During the process of coal spontaneous combustion (CSC), a plethora of combustible gases alongside inert gases, such as CO2, are copiously generated. However, prior investigations have regrettably overlooked the pivotal influence of inert gas production on the propensity for methane explosions during CSC. To investigate the impact of the flue gas environment generated by CSC, containing both combustible and inert gases, on the risk of methane explosion, a high-temperature programmed heating test system for CSC was employed to analyze the generation pattern of flue gas. It was found that CO, CO2, and CH4 were continuously generated in large quantities during the process of CSC, which are the main components of CSC flue gas. The effect of the concentration and component ratio (CCO2/CCO) of the flue gas on the methane explosion limit was tested. It was found that the CSC flue gas led to a decrease in the methane explosion limit, and that the explosion limit range was facilitated at 0 < CCO2/CCO < 0.543 and suppressed at CCO2/CCO > 0.543. As the temperature of CSC increases, the risk of methane explosion is initially suppressed. When the coal temperature exceeds 330~410 °C, the explosion risk rapidly expands.

Comprehensive evaluation of low-temperature oxidation characteristics of low-rank bituminous coal and oil shale

The coexistence of coal and oil shale mining conditions exacerbates the complexity of coal spontaneous combustion (CSC) prevention, so conducting in-depth research on the spontaneous combustion characteristics of coal, oil shale, and their mixed samples is necessary. A programmed heating system simulated the low-temperature oxidation process of bituminous coal and oil shale under different air volumes. It was found that CO concentration, C2H4 concentration, and Graham's fire coefficient (R1, R2) can be used as indicator gases to predict the CSC process. Compared with oil shale and mixed samples, bituminous coal has a higher CO production rate, oxygen consumption rate, heat release intensity, and lower apparent activation energy during the slow oxidation stage. Meanwhile, bituminous coal also has lower peak values of minimum float coal thickness, lower limit oxygen concentration, and maximal air leakage intensity, which means that bituminous coal in the goaf is more prone to oxidation. However, the abundant free hydrogen bonds in oil shale can stabilize the hydrogen-deficient functional groups of bituminous coal, which weakens the oxidation ability of the mixed sample during the accelerated oxidation stage. In addition, the increased air volume fraction increases the oxygen adsorption efficiency of the mixed sample throughout the low-temperature oxidation process, which means that the M70 sample has a higher CSC risk. The results have enriched the research on the spontaneous combustion characteristics of coal, oil shale, and mixed samples, which may strengthen the management and control of CSC in coal and oil shale co-mining mines.

Study on the precursor characteristics of coal energy spontaneous combustion process using infrasound wave monitoring and warning

The spontaneous combustion of coal energy has seriously threatened energy security, and there is an urgent need for monitoring and warning of coal energy. Therefore, this article innovatively proposes a method of using infrasound waves to monitor coal energy spontaneous combustion, establishes a coal spontaneous combustion(CSC) infrasound wave experimental testing system, and studies the precursor characteristics of coal energy spontaneous combustion process. The results indicate that there is a good positive correlation between the amplitude of the dominant frequency of the infrasound wave generated by CSC and temperature, with a correlation coefficient of R2 > 0.85. The energy proportion of the infrasound signal from 0 to 0.12Hz exceeds 80 %. And as the CSC stage progresses, the energy of infrasound waves in the 0.04–0.08Hz frequency band increases significantly, and the changes in infrasound signals in this frequency band have a good correlation with temperature, with a correlation coefficient above 0.8. This frequency band is the main frequency band of infrasound waves during the CSC process. The research in this article provides a theoretical basis for the application of infrasound wave monitoring and warning of coal energy spontaneous combustion, and it is of great significance to ensure the safe mining of coal energy.

Research on fire early warning index system of coal mine goaf based on multi-parameter fusion

In order to improve the precision of goaf fire early warning outcomes, this paper obtains the temperature characteristic index of goaf fire early warning by using a coal spontaneous combustion thermogravimetric test and a coal spontaneous combustion programmed heating test. The major gas index and auxiliary gas index for early warning are derived using the integration of the Graham coefficient and grey correlation approach. The D-S evidence theory, which involves optimizing weight allocation, is utilized to integrate the early warning temperature index and various gas indexes. Based on the fusion results, a coal mine goaf fire early warning index system is developed through multi-parameter fusion. The early warning index system is then validated through a programmed heating experiment. The results show that the process of coal spontaneous combustion can be categorized into six distinct stages: latent stage, oxidation stage, critical stage, pyrolysis stage, fission stage, and combustion stage. These stages are determined by the characteristic temperatures of coal spontaneous combustion, which are 31.7 °C, 54.8 °C, 153.7 °C, 204.5 °C, and 241.6 °C. The major gas index for early warning of goaf fires can be determined by 100∆(CO)/∆O2(%). Additionally, auxiliary gas indexes such as C3H8/CH4, C3H8/C2H6, C2H4/C2H6, and C2H2 can be used for goaf fire early warning. The programmed heating experiment shows that the early warning system software is designed by the multi-parameter fusion goaf fire early warning index system is accurate and effective. The selection of the goaf fire early warning index is more rational and precise when using the multi-parameter fusion goaf fire early warning index system based on the D-S evidence theory of weight allocation. It offers robust support for enhancing the goaf fire early warning index system and predicting coal mine goaf fires.

Effect of Resveratrol on physicochemical structure evolution of lignite during spontaneous combustion

Studying the evolution of the physicochemical structure of coal during coal spontaneous combustion (CSC) by antioxidants is of great significance for revealing the mechanism of CSC and preventing it. The effects of three concentrations of Resveratrol (RES) on the physicochemical structure evolution of coal during the low-temperature oxidation (L-TO) process of CSC were comprehensively analyzed through low-field nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) experiments. The results showed that the pore cracks in the coal develop more fully with the increase in oxidation temperature. Besides, there was an increase in porosity and permeability, and a full development of pore throat. Based on the T1-T2 2D fluid identification results, it was found that as the oxidation temperature increased, the adsorption capacity and permeability of the coal were stronger. RES can effectively inhibit the CSC process of coal, with a maximum reduction of 23 % in porosity and a maximum reduction of 82 % in permeability. The hydroxyl groups and CH3/CH2 of coal samples treated with RES decreased by a maximum of 42 % and 43 %, respectively. The oxygen-containing functional groups increased by a maximum of 77 %. RES can not only cover on the coal surface to prevent oxygen from seeping into the coal, but also infiltrate into the pores of coal to inhibit the combination of the active functional groups and oxygen molecules.

Spontaneous combustion properties and quantitative characterization of catastrophic temperature for pre-oxidized broken coal under stress

Coal Spontaneous Combustion (CSC) is one of the most important natural disasters in coal mining safety production. To deeply restore the real state of CSC left in goaf during the face mining of coal mines, the experiments are carried out to simulate the oxidation characteristics of coal left in goaf under the coupling of the stresses (0 MPa, 4 MPa, 8 MPa) and the pre-oxidation temperatures (25 °C, 70 °C, 120 °C, 180 °C) employing the load-pressure-based device equipped with temperature-programmed. The oxidation characteristic parameter of CO gas generation, the O2 consumption rate, the apparent activation energy (Ea), and the critical temperature(T1) are calculated. It is found that both the pre-oxidation temperature and the stress have a promotion range for coal spontaneous combustion, and although they inhibited each other beyond the promotion range, they still show a promotion result. The pre-oxidation temperature and stress mainly affect the content of oxygen-containing functional groups and the permeability, thus influencing the process of coal spontaneous combustion. Based on the engineering application, a cusp catastrophe model is established to predict the catastrophic temperature of coal spontaneous combustion, and it is verified that the catastrophic temperature could correctly characterize the transition of coal spontaneous combustion, and it is found that the catastrophic temperature lagged behind the critical temperature, which provides sufficient time and space for the prevention and control of coal spontaneous combustion.

Coal Secondary Oxidation Thermodynamic Behaviors Affected by Pre-Heating at Different Oxygen Concentrations

ABSTRACT To investigate the impact of pre-oxidation oxygen concentration on the propensity of coal spontaneous combustion, thermogravimetric analysis was used to obtain thermal characteristic curves for raw coal and pre-oxidized coal with five different oxygen concentrations. The coal spontaneous combustion process was categorized into three phases: water-loss and weightlessness, oxygenation and weight gain, and combustion phase. It reveals that characteristic temperature points of oxidized coal were lower than that of raw coal, and pre-oxidation plays a role in enhancing the coal oxidation to varying degrees. During the phase of oxygenation and weight gain, the activation energy of oxidized coal decreases from 44% to 84% of that of raw coal. The positive effect on coal secondary oxidation is initially reduced, then increased with the increasing of pre-oxidation oxygen concentration. The sample pre-oxidized with 15% oxygen concentration is the most easily spontaneous combustion, and the total activation energy of its oxidation reaction is 57% of that of the raw coal, the characteristic temperature of which lowered by an average of 7.4°C. It will be conducive to revealing reignition mechanism of coal and preventing coal secondary spontaneous combustion.

Study on Thermal Behavior Characteristics and Microstructure Evolution Mechanism of Residual Coal Combustion Process in Deep High Initial Temperature Environment

ABSTRACT The shallow coal seam resources are gradually reduced, the depth of coal seam mining is increased, and the underground temperature is increased, which makes the risk of residual coal fire increase year by year. In order to explore the transformation path of functional groups during oxidation and the caloric release characteristics of residual coal in deep coal mine, the microcosmic changes of coal oxidation process in deep mine were analyzed by in situ diffuse reflectance (In situ FTIR) and electron spin resonance (EPR) experiments, and macroscopic characteristics such as characteristic temperature of residual coal were tested by synchronous thermal analysis experiment. In FTIR results, it is observed that hydroxyl groups, active aliphatic hydrocarbon structures, and active oxygen-containing groups are key chemical structures involved in the oxidation process of residual coal, displaying a strong correlation transformation phenomenon. This can be described as follows: oxygen absorption led to a negative correlation between aliphatic hydrocarbon structures and hydroxyl groups, while the conversion of aliphatic hydrocarbon structures into carboxyl and aldehyde groups resulted in a negative correlation between aliphatic hydrocarbons, carboxyl groups, and aldehyde groups. Active oxygen-containing functional groups showed a positive correlation. With the increased of free radical concentration, the type of free radicals increased and the linewidth (ΔH) increased. The high-temperature environment intensified thermal behavior tendencies, increased the number of active structures, and raised the risk of spontaneous combustion. The research results provided a theoretical basis for understanding the process of coal spontaneous combustion, and had important reference value for ensuring the safe mining of deep coal seams and implementing effective disaster prevention measures.

Comparative Study on Macroscopic Parameters of Coal Spontaneous Combustion Under Different Test Methods

ABSTRACT The quantitative characterization and the accurate determination of the degree of danger of coal spontaneous combustion (CSC) characteristics are the hotspots and difficulties in the field of coal mine safety. This study compares the test results obtained from the Large-scale CSC experiment and the Kilogram-level CSC experiment and preliminarily determines the main macroscopic characterization parameters of CSC in Huangling No.2 well (including characteristic temperature, spontaneous combustion period, oxygen consumption rate and heat release intensity). At the same time, the various rules of the limit parameters of CSC (including the minimum float coal thickness, the minimum oxygen concentration and the maximum air leakage intensity) of the two experimental results are compared and analyzed. The results show that compared with the Large-scale CSC experiment, the Kilogram-level CSC experiment has the characteristics of rapid and accurate determination of macroscopic characterization parameters of CSC. Therefore, it can be used for the test, the accurate determination of characterization parameters and the determination of the tendency of the CSC process. It is of great significance to the prediction and the risk of CSC.

Inhibition property of gasification ash to coal spontaneous combustion

In view of the problems of uncomprehensive utilization of solid waste resources and environmental pollution caused by the stacking of coal gasification cinder, the gel inhibition performance of coal gasification cinder was studied. A new kind of anti-fire gel material was prepared by crosslinking with gasification cinder as the base material, HPMC as the gelling agent, and Na2CO3 as the coagulant. The effect of coal to oil gasification ash gel on coal spontaneous combustion and activation energy was analyzed in essence and phenomenon through temperature-programmed experiments and determination of marker gases. Results showed that the concentration of CO gas and C2H4 gas of anthracite during the process of temperature oxidation decreased by 38.1% and 65.8%. The inhibition rate after gel treatment was 56.4%, and the activation energy was 6.5%. It shows that the adjunction of ash gel can validly mitigate the reaction rate of the coal spontaneous combustion process and inhibit the reaction procedure between coal and oxygen. The inhibition performance is better than the common CaCl2.

Kinetic properties of non-caking coal spontaneous combustion by evolution of its functional groups

Coal spontaneous combustion (CSC) continues to generate huge economic losses and considerable casualties. Thew aim of this study is to further reveal the evolution of microstructures and coal spontaneous combustion mechanisms during natural oxidation. Coal samples with known CSC tendencies were selected to explore their microstructure and the characteristics of their reaction kinetics. This information is of great benefit to mine safety engineers and risk management professionals. Proper characterisation of risk leads to improved early warning detection, and the possibility of CSC retardant materials. A low-metamorphic type, non-caking coal sample was obtained from a Mengcun Coal Mine, and the relative content of the active functional groups and evolution of the key active groups were examined as temperature varied. Fourier transform infrared spectroscopy (FTIR) and the Coats-Redfern and Achar calculus methods were used to determine the reaction kinetics of the key active groups during CSC. The most probable mechanisms were determined, and the spontaneous combustion kinetic reaction mechanism was derived. Initial analysis of the sample revealed multiple active groups, active nuclear substances, a high calorific value, and a strong oxidative ability. There were a large number of oxygen containing functional groups and activity was high, due to the high intermolecular hydrogen bond content, and the apparent activation energy for ignition was low. Within the reaction, the aliphatic hydrocarbons were relatively stable; they had the largest apparent activation energy and were the least reactive. Methylene was the most important group consumed by aliphatic hydrocarbons in the CSC process. The reaction mechanism of the various groups were determined via Avrami-Erofeev equation. The large number of active groups produced and consumed was best described by the three-dimensional Ginstling-Brounshtein model.

Study on the microcosmic mechanism of inhibition of coal spontaneous combustion by antioxidant diphenylamine

Diphenylamine has been applied to suppress coal spontaneous combustion with good results, but its microscopic reaction mechanism is not clear. In this paper, the free radical reaction process of coal spontaneous combustion is calculated more systematically, and the quantum chemical method is applied to analyze in detail the process of diphenylamine depletion of reactive free radicals in coal from three perspectives: hydrogen atom transfer, direct radical capture, and regeneration cycle chain. By destroying the molecular structure of coal to generate free radicals as the initial condition of coal spontaneous combustion, the oxidation process of the free radical chain reaction was analyzed, the thermodynamic data of all reactions were calculated, the microscopic mechanism of free radical capture by diphenylamine was revealed, and the transition state structure model of the reaction process was given. The active sites of each reactant were determined by quantitative molecular surface analysis, the spontaneity of the reaction was measured by the free energy change, and the interaction relationship between different conformations was graphically represented by applying the IRI (interaction region indicator) method. The results show that most of the free radical reactions during the spontaneous combustion of coal are exothermic, and they provide heat for the spontaneous combustion of coal, which can react directly with oxygen when accumulated to a certain temperature. Diphenylamine can break the N-H bond, allowing hydroxyl radicals and carbon radicals to obtain hydrogen atoms to form stable compounds, and the generated diphenylamine radicals can reduce the content of free radicals in coal by direct capture. In addition, the process of diphenylamine inhibition of coal spontaneous combustion has a circular regeneration chain, which can indeed effectively reduce the content of reactive radicals and inhibit the spontaneous combustion of coal, which is reflected in the macroscopic level of reducing the generation of coal spontaneous combustion indicator gas, which is consistent with the experimental results.

Preoptimal analysis of phase characteristic indicators in the entire process of coal spontaneous combustion

To accurately predict the development degree of coal spontaneous combustion (CSC), the CSC process was investigated using a programmed high-temperature-heating experimental system, and the variation law of index gas concentration in the holistic process of CSC and oxidation is formulated. Additionally, the accuracy of the experimental system was evaluated using experimental design for thermal analysis, and the correlation between gas index and apparent activation energy was determined using grey correlation analysis. The results indicated the following. In the critical temperature stage (0–100 °C), φ(CO)/φ(CO2) should serve as the main index and C2H4 should serve as the auxiliary index; in the crack-active-speedup temperature stage (100–260 °C), CO and φ(C2H4)/φ(C2H6) should serve as the main index and R1, the Graham index, and φ(C2H4)/φ(CH4) should serve as auxiliary indexes; in the speedup-ignition temperature stage (260–370 °C), R2 and the Graham index should serve as main indexes and φ(CO)/φ(CO2), C2H4, and R1 should serve as auxiliary indexes; in the ignition temperature (370–500 °C), R3 should serve as the main index and R2, the Graham index and C2H4 should serve as auxiliary indexes. Among them, the grey correlation degrees among the Graham index, Grignard fire coefficient, and apparent activation energy were the highest, reaching 0.91.

Effect of molecular structure change on the properties of persistent free radicals during coal oxidation

This study is aimed at exploring the effect of molecular structure changes on the properties of persistent free radicals in coal during the heating process of coal spontaneous combustion (CSC). Therefore, the persistent free radicals and main functional groups variation characteristics in the process of coal oxidation were analyzed by means of in situ electron spin resonance and in situ infrared spectroscopy, and the change relationship between the molecular structure of coal and the persistent free radicals in coal during the reaction was further discussed by correlation analysis. The results showed that the concentration of persistent free radicals showed a stage change of “first decreasing, then increasing and then decreasing”. The g-factor decreases gradually and the heteroatom free radicals are consumed continuously. Dehydrogenation oxidation reaction causes the weakening of the “electron-proton” interaction, which narrows the line-width (ΔH) of free radicals. The phenolic hydroxyl as the electron donating group is converted into -CO functional group through dehydrogenation and oxidation reaction, which promotes the formation and accumulation of persistent free radicals in coal. Under the influence of phenolic hydroxyl, the relationship between the stretching vibration strength of aromatic ring CH and the properties of persistent free radicals in coal shows a similar change law with phenolic hydroxyl. In addition, the chain structure represented by –CH2-, –CH3/–CH2- is continuously consumed in the oxidative dehydrogenation reaction, triggering a series of free radical reactions. The free radicals formed in this process are affected by the steric hindrance of polymer networks and the electron delocalization of aromatic group in coal, so the persistent free radicals can be formed and accumulated. The dehydrogenation and oxidation reaction of the active group led to the reduction of g-factor and ΔH. Persistent free radicals play an important role in the free radical chain reaction that triggers CSC, so preventing the dehydrogenation and oxidation reaction of hydroxyl (especially phenolic hydroxyl) and aliphatic hydrocarbons (especially –CH2- and –CH3/–CH2-) is the key to prevent CSC.

Study on the Coupling Characteristics of Infrasound–Temperature–Gas in the Process of Coal Spontaneous Combustion and a New Early Warning Method

ABSTRACT The phenomenon of coal spontaneous combustion poses a serious threat to mine safety, and monitoring and warning of coal spontaneous combustion has become an important issue that needs to be urgently addressed in coal mines. The current monitoring and early warning methods for coal spontaneous combustion have their limitations, and a single indicator cannot accurately mark the degree of coal spontaneous combustion danger inside the goaf. Therefore, this article proposes a new method for monitoring coal spontaneous combustion through infrasound waves. Infrasound waves have advantages such as low attenuation and long transmission distance. However, current research on monitoring and warning coal spontaneous combustion in goaf through infrasound waves is not yet complete, and there is a lack of research on the characteristics of infrasound signal changes during coal spontaneous combustion. Based on this, the article first tested the characteristic temperature and release changes of indicator gases (CO, C2H4) through thermogravimetric experiments and coal oxidation and heating experiments. Then, the generation and variation of infrasonic signals during coal spontaneous combustion (CSC) was studied and analyzed using a self-designed CSC infrasonic testing system. The results showed that obvious infrasound signals could be generated during the CSC process, there is a good mapping relationship between signals and temperature. Furthermore, the analysis revealed the inherent relationship between the infrasonic signal, temperature, and indicator gas of coal at different oxidation stages. The research in this article has promoted the use of infrasound waves for temperature inversion and promoted the development of multi-parameter analysis and early warning of CSC, which is of great significance for the field of CSC monitoring.