Study on the effect of composite hydrogel inhibitors on the heat release characteristics of coal oxidation

Pan, Rongkun; Li, Xiangchen; Li, Huai-Zhen; Chao, Jiangkun; Jia, Hailin; Ma, Zhihui

doi:10.1016/j.fuel.2021.122019

Cited by 22 publications

(6 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reaction rate of the oxidation increases with increasing concentration of oxygen and can be lowered by plugging. Plugging reduces the contact between the coal and oxygen .…”

Section: Introductionmentioning

confidence: 99%

Study on the Inhibition Characteristics of Coal Spontaneous Combustion by Silica Gel Foam

Zhang,

Wen

et al. 2024

ACS Omega

View full text Add to dashboard Cite

The spontaneous combustion of residual coal in abandoned mining areas severely affects the safe and efficient extraction of coal, employee occupational health, and regional environmental ecology. A technical measure for preventing and controlling the spontaneous combustion of residual coal involves injecting antispontaneous combustion materials into abandoned areas. In this study, the composition, preparation, and mechanism of action of silica gel foam, a material used to suppress spontaneous combustion during coal mining, were investigated to improve the performance of materials designed to prevent spontaneous combustion in abandoned areas. The inhibitory efficiency improved, and the mechanical strength and stability of the foam liquid film increased upon adding modified antioxidants and nanosilica particles to the gel foam. Macro performance tests, microstructural characterization, and chemical inhibition mechanism analyses verified the efficacy of silica gel foam for suppressing spontaneous combustion. The air leakage resistance of the silica gel foam effectively increased the air leakage resistance of the coal samples at different pressures. New radicals formed during the spontaneous combustion of coal comprising different inhibitors, as indicated by the g-factor results of electron paramagnetic resonance (EPR) spectroscopy analysis; the formation of radicals initially decreased and then increased when the inhibitor material changed. The concentration of free radicals decreased markedly during the spontaneous combustion process of both raw and inhibited coal samples at low oxidation temperatures (∼60−100 °C), indicating a marked inhibitory effect.

show abstract

“…The reaction rate of the oxidation increases with increasing concentration of oxygen and can be lowered by plugging. Plugging reduces the contact between the coal and oxygen .…”

Section: Introductionmentioning

confidence: 99%

Study on the Inhibition Characteristics of Coal Spontaneous Combustion by Silica Gel Foam

Zhang,

Wen

et al. 2024

ACS Omega

View full text Add to dashboard Cite

show abstract

“…Xue [20] utilized electron spin resonance and scanning electron microscopy to clarify the inhibition mechanism of an antioxidant-type composite inhibitor on coal oxidation. Pan [21] used a C600 microcalorimeter to examine the mechanism and inhibitory impact of an inhibitor on the oxidation heat release process in the spontaneous combustion of coal.…”

Section: Introductionmentioning

confidence: 99%

Research on the Inhibitory Effect of Hydrated Phase Change Materials on Spontaneous Combustion in Coal

Wu,

Shi,

Shao

et al. 2024

Fire

View full text Add to dashboard Cite

In order to study the effect of hydrated phase change materials on the suppression of spontaneous combustion in coal, a thermogravimetric experiment and a reaction activation energy analysis experiment were conducted to explore the changes in the combustion characteristic parameters, characteristic temperature, and activating energy of gas coal, long-flame coal, meagre coal, and lean coal before and after adding hydrated phase change materials. The research results indicated that hydrated phase change materials increased the characteristic temperature point of the coal samples and had effective inhibitory effects on different stages of the oxidation process. However, the effect was best at low temperatures, as hydrated phase change materials undergo phase change and absorb heat when heated at low temperatures, isolating coal from contact with oxygen. The activating energy increased by 1.138–23.048 KJ·mol−1 and the mass loss was reduced by 1.6%–9.3% after inhibition of the coal samples, indicating that the oxidation rate of the various coal samples was slowed down and, thus, spontaneous combustion can be suppressed through the use of hydrated phase change materials. At the same time, this material reduced the combustibility indices of meagre coal and lean coal, as well as the comprehensive combustion indices of long-flame coal and gas coal.

show abstract

“…The temperature will gradually increase at a fast speed and eventually develop into the rapid heating and combustion stages. − Therefore, preventing and controlling the spontaneous combustion of coal in the high-temperature area is the key to preventing and putting out a fire in a goaf. However, the current anti-extinguishing measures strive to cover the entire goaf area of the mine, which results in a large amount of waste of anti-extinguishing materials. Once these materials are injected into the goaf, the moisture in the materials frequently starts to evaporate at the low-temperature stage of the coal due to air leakage of the goaf.…”

Section: Introductionmentioning

confidence: 99%

Mining Polyethylene Glycol-Based Thermosensitive Hydrogel Materials: Preparation and Flame Retardant Properties

et al. 2023

View full text Add to dashboard Cite

A new type of efficient and anti-extinguishing materials to inhibit coal spontaneous combustion is required because of the current situation of the short activity cycle of existing anti-extinguishing technology. Now, polyethylene glycol (PEG) was used as a water-absorbing monomer to polymerize various substances to prepare an AB-type mining thermosensitive hydrogel that was obviously thermoresponsive. The thermosensitive hydrogel, which is low-cost and stable, can be stored for a long time, and it is prepared by compounding A and B components. The orthogonal experiments determined the optimal ratio of component A, while the controlling variable experiments determined the optimal ratio of component B. The thermal stability and flame-retardant properties of the AB-type thermosensitive hydrogel were analyzed during the process of natural oxidation of coal, and the temperature responsiveness of thermosensitive hydrogels was investigated at different temperatures. The results showed that the optimal ratio of polyethylene glycol:methyl cellulose:sodium carboxymethyl cellulose:guar gum of component A was 6:6:1.2:1.5; and the ratio of bentonite:kaolin:Mg(OH)2 of component B was 2:1:1. When the ratio of component A to component B was 1:2, the AB-type thermosensitive hydrogel shows the best flame retardant properties. When this ratio of gel was applied to coal samples, the weight loss was just 6%, and the reduction of CO was as high as 72.6%. The gel, which was convenient for transportation in mining pipelines, had strong fluidity at low temperatures and rapid temperature response. As the temperature rose, a phase transition occurred gradually, and after the phase transition, a high-viscosity solid substance was formed, whose viscosity was approximately 11 times that of the room temperature. It plugged the pores effectively, and in the high-temperature region, the occurred phase transition gathered to extinguish the fire. It is a new type of high-efficiency anti-extinguishing material with excellent properties.

show abstract

Study on the effect of composite hydrogel inhibitors on the heat release characteristics of coal oxidation

Cited by 22 publications

References 35 publications

Study on the Inhibition Characteristics of Coal Spontaneous Combustion by Silica Gel Foam

Study on the Inhibition Characteristics of Coal Spontaneous Combustion by Silica Gel Foam

Research on the Inhibitory Effect of Hydrated Phase Change Materials on Spontaneous Combustion in Coal

Mining Polyethylene Glycol-Based Thermosensitive Hydrogel Materials: Preparation and Flame Retardant Properties

Contact Info

Product

Resources

About