Influence of High Temperature Thermal Radiation on the Transition Characteristics of Coal Oxidation and Spontaneous Combustion

Liancong Wang,Weizhao Hu,Yuan Hu

doi:10.3389/fmats.2021.778485

Abstract

In the goaf of the coal mine, there will be some high-temperature points before or during the fire. Under certain conditions, these high-temperature points will radiate heat to the surrounding coal in the form of thermal radiation, which, in turn, may also ignite the coal. Taking this situation into consideration, this study aims to investigate the influence of high-temperature thermal radiation on the transformation characteristics of coal oxidation and spontaneous combustion using the high-temperature thermal radiation method. The results show that an increase in thermal radiation value reduces the ignition time of coal gradually. The peak heat release rate, total heat release, peak smoke release rate, and total smoke release gradually increase. Additionally, the total carbon monoxide release reduces gradually, and the peak carbon dioxide production rate increases gradually. It is worth noting that as the heat radiation value increases, the peak value of CO production rate of lignite and bituminous coal is noted to decrease gradually, whereas that of anthracite increases gradually. The total carbon dioxide emissions of bituminous coal and anthracite increased gradually, whereas the total carbon dioxide emissions of lignite increased firstly and then decreased. This work proposes a novel method to study the coal oxidation and spontaneous combustion by a widely-recognized combustion apparatus.

Highlights

It is well known that there are three main forms of heat transfer: conduction, convection and radiation
It is worth noting that no matter what the thermal radiation value increases to, anthracite cannot be ignited, which is deemed consistent with the spontaneous combustion tendency of anthracite
The reason is that bituminous coal has a higher oxygen content than anthracite, making the coal burn more vigorously and release more heat (Riaza et al, 2014)

Summary

Introduction

It is well known that there are three main forms of heat transfer: conduction, convection and radiation Because it is a poor heat conductor, and the space in the goaf of coal mine is relatively closed, the heat is mainly transferred to the surrounding coal in the form of thermal radiation during and after the oxidation and spontaneous combustion of coal (Wen et al, 2017; Wang et al, 2018; Shao et al, 2021; Xiao et al, 2021). As one of the key factors to initiate or promote coal oxidation and spontaneous combustion, there are few reports on the effect of high temperature thermal radiation on the transformation characteristics of coal oxidation and spontaneous combustion (Wang L et al, 2019)

Objectives

Results

Conclusion