Experimental study on combustion and extinguishing of secondary oxidation coal

Thespontaneouscombustionofcoalinthegoaf,whichbelongstosecondaryoxidationcoal seriouslythreatens the safe production of coal mines.Nitrogen can be used as a fire extinguishing agenttoinhibitspontaneouscombustionofresidualcoal.Inordertostudytheeffectofnitrogenonsecondary oxidation coal,thermogravimetric analysis and temperature programmed system are used to carryoutexperimentsonandanalysisofheatingprocessandextinguishingprocess.Duringtheheating process,astheconcentrationofnitrogenincreased,thecharacteristictemperaturesincreased,andnitrogen inhibited the combustion of secondary oxidation coal.In the process of cooling and extinguishingfire,thetemperatureandindicatorgasCOconcentrationwereusedasmonitoringparameterstotestthefireextinguishingeffect.Theanalysisshowsthatwhenamixtureofnitrogenandair withtheratioof50% /50%,wasintroducedintothesecondaryoxidationcoalprogrammedto400℃, thetimewasreducedby38.0% comparedwiththenaturaltemperaturedrop,alsothetimeforCO concentrationtodropto0wasshortenedby42.1%.Thehigherthenitrogenconcentration,theshorter thefire-extinguishingtimeofthesecondaryoxidationcoal,andthelesstheproductproduced,thebetterthefire-extinguishingeffect.