A macro analytic method for coal tar derived from pyrolysis at different temperatures

There is considerable interest in experimental and computational investigations of how tar is affected by the conditions employed for coal pyrolysis. Although a multitude of analysis methods for coal tar have been developed and tested, few have focused on the dynamics of tar formation on a macro level. In this work, an experimental device was designed to analyze the dynamic characteristics of the tar release process at different temperatures. The tar yield was continuously recorded during the process of coal pyrolysis; then the release proportion of coal tar, which was similar to weightless conversion in thermogravimetric analysis, was defined. Based on the macroscopic phenomena of tar release, dynamic equations were deduced to establish a hybrid dynamic model for tar generation. The fitting result illustrates that the established hybrid dynamic model is effective for predicting the tar yield. Furthermore, the shrinking core model, a multi-particle first-order reaction, and the Anti–Jander diffusion equation were built to elucidate the macro release mechanisms of coal tar.