Gasification tests at a bench scale bubbling fluidized bed plant for syngas production: Evaluation of primary methods for gas cleaning and conditioning

An advanced gasification process aiming at highly efficient and cost-effective CHP production via SOFC is being developed. Due to the demanding technical specifications of commercial SOFCs about the content of organic and inorganic contaminants, the use of both primary and secondary methods for gas conditioning was considered. The present work concerns the results collected to evaluate the effectiveness of in-bed additives under the gasification conditions of S/B 0.5, ER 0.25, Tgasif. 850 °C. As representative feedstocks, Olive Pomace and Refuse Derived Fuel were considered. Specifically, the tests were carried out at a bench scale bubbling fluidized bed reactor using a mix olivine/calcined-dolomite, 70:30%-wt, as bed inventory and alkali-metal carbonates (Na2CO3, K2CO3) as additives for sour gases removal. Compared to olivine, the use of the mixed bed allowed a tar reduction of about 40%-wt, based on the chromatographic data; a reduction up to 35% and 45%, by weight, was estimated on HCl with K2CO3 and Na2CO3, respectively. In the case of H2S the highest efficacy (> 90%-wt) was associated to the capture effect of the calcined dolomite.