Parametric studies on catalytic pyrolysis of coal-biomass mixture in a circulating fluidized bed

Abstract

Pyrolysis is an efficient way of thermally converting biomass into fuel gas, liquid product and char. In this research, pyrolysis experiments were carried out in a circulating fluidized bed reactor with a riser diameter of 25 mm and height 1.65 m. The biomass used was corn cobs. The experiments were conducted systematically using two level factorial design with temperature ranging from 650 to 850 degree Celsius, corn cobs and catalyst contents in feed ranging from 0 to 100%, and from 1 to 5 wt%, respectively, and Ni loaded on catalyst ranging from 5 to 9 wt%. The results showed that when temperature and catalyst contents in feed and Ni loaded on catalyst increased, the percent of hydrogen and carbon monoxide increased. The amount of corn cobs was found to have an effect only on the composition of hydrogen. Carbon dioxide was also observed to increase slightly. On the other hand, the percent of methane was considerably decreased. The optimum conditions were 850 degree Celsius, corn cob content in feed of 100%, catalyst content in feed of 5% and Ni loaded on catalyst of 9%. At this condition the percentages of hydrogen and carbon monoxide were 52.0 and 18.0, respectively.