Comparison of pyrolysis behavior between pure coal and mixture of coal/CaO

Abstract

The pyrolysis of coal mixing with CaO can produce uniform mixture of residual char and CaO, which can be further converted into calcium carbide for providing alternative way of ethyne production. Therefore, knowledge on the pyrolysis behavior of coal at the presentation of CaO is important for the industrial production of such mixture of residual char and CaO. By comparing the TG/DTG curves of pure coal and mixture coal (with CaO), it was found that the addition of CaO can promote the release of volatiles especially at lower temperature. The Distributed Activation Energy Model (DAEM) were developed for pure coal and mixture coal separately for analyzing their corresponding pyrolysis kinetics. While 2-DAEM with two-Gaussian functions is accurate enough for describing the pyrolysis of pure coal, 3-DAEM is more suitable for capturing the main pyrolysis characteristics of mixture coal. DAEM results show lower average activation energy for the pyrolysis of mixture coal than that of pure coal, further demonstrating the catalysis effect of CaO on coal pyrolysis.