Method of pre-oxidation treatment for spontaneous combustion inhibition and its application

Abstract A method named “pre-oxidation treatment for spontaneous combustion inhibition” was proposed to proactively prevent coal spontaneous combustion. In this method, coal samples are firstly oxidized under room temperature by an oxidizer, which have an oxidizing capacity equivalent to the capability of oxidizing only active functional groups in coal. In this way, functional groups residing in the coal structure with high reactivity will be oxidized and heat will be released at the same time. With a large amount of water protection set up in advance, the heat can be released safely. After the highly active functional groups are oxidized, the reaction products left contain more stable functional groups with low activity, thus reducing the risks of spontaneous combustion. Underpinned by the theory, the method was tested by using different aqueous solutions of oxidants to pre-oxidize various coal samples. Results show that the method of pre-oxidation treatment for spontaneous combustion inhibition can significantly reduce the risk of coal spontaneous combustion. Among all the tested aqueous solutions of oxidants, the sodium persulfate solution is the most appropriate one.