Cracking of tar by steam reforming and hydrogenation

Gasification is a thermo-chemical conversion process used to produce syngas through partial oxidation. Gasification technology provides the opportunity to convert a feedstock into fuel gases or synthetic gases. Raw syngas produced by gasification needs cleaning before being used subsequently. One of the impurities in raw syngas is tar, a group of long-chain sticky hydrocarbons that clog the subsequent devices. One useful way of removing tar is to degrade it thermally into simple fuel gases (e.g., hydrogen, methane). This adds to the heat value of syngas too. In this work, an equilibrium model is reported that simulates the thermal cracking of three representative tars, viz. toluene, benzene and naphthalene, by steam reforming and hydrogenation and estimates the cracking products. Parametric studies have also been carried out to understand the influence of different operating conditions such as temperature and reactant concentrations on the composition of product gas mixture. Reported results may be useful to determine optimum operating conditions in tar cracking systems.