(421ae) A Catalytic Gasification of Indonesian Kideco Coal in Two Flow Regimes Fluidized Bed Gasifier

In this study, coal only gasification and catalytic coal gasification were compared with varying the operating conditions. 3 different gasification modes were evaluated. First one is coal only gasification, second one is the traditional catalytic coal gasification with dispersing catalyst particles, and third one is newly proposed catalytic coal gasification with coating catalysts onto the internals (coiled heat transfer tube).

Experimental works of hot mode catalytic coal gasification were carried out in a fluidized bed with 0.05 m ID and 0.4 m height in lower reaction part, and 0.1 m ID and 0.7 m height in upper reaction part. A cyclone was installed inside the bed in order to prevent fly ash scattering and to make large particles (unburned char or bed materials) return to the fluidized bed reactor. In addition, the coiled heat transfer tubes were installed in upper reactor for controling inside bed temperature and fixing the catalyst. As the catalyst is fixed to the internal, agglomeration among coal, bed materials, and catalysts can be avoid.

Coal was fed into the gasifier by screw feeder up to 2 kg/h and the catalysts were disperesed into the reactor before gasification reaction. The operating temperature and pressure were 800 °C and 1 bar respectively. The gas mixture of O₂ and N₂ for adjusting the O₂/C ratio with maintaining specific superficial gas velocity was introduced into bottom of the gasifier. Steam was also fed into the reactor considering H₂O/C ratio. The proximate analysis of Kideco coal is volatile matter 38.14%, fixed carbon 39.99%, moisture 10.00%, and ash 11.87%. The ultimate analysis is C 64.59%, H 4.83%, N 1.51%, S 0.48% and O 15.40%, respectively.