Response of Macroscopic Coal Oxidation and Pyrolysis Parameters to Different Extractants

Abstract

ABSTRACT The active structure of coal molecules is one of the key factors affecting the characteristics of coal spontaneous combustion (CSC). By actively stripping or reducing the key active structure of coal molecules, and then studying the influence of different structures on the oxidation characteristics of coal, it is helpful to accurately and efficiently inhibit CSC. Herein, using coal samples from Caojiatan Mine in Shaanxi Province, China, the CSC characteristics of 10 coal groups treated with different solvents and the response of the macroscopic coal oxidation and pyrolysis parameters to each extractant were investigated. The extractant type considerably affected CSC, and the oxidization of coal was most responsive to biomass extraction agents, which had the best weakening effect on CSC. The order of CSC characteristics of extracted coal from strong to weak is AE> YM> CYC> AOT> CYH> EG> MT> TP> THF> CYC + AOT + AE> EG + TP. In general, all extraction reagents in each group have a certain weakening effect on the CSC activity of coal samples. The extraction of aromatic hydrocarbon structures can effectively delay the oxidation of coal. The study provides new insights for the development of CSC mitigation technology and have important practical significance for active prevention and control of CSC risks.