Modeling reaction kinetics of steam gasification for a transport gasifier

Abstract The fraction of carbon in char converted by steam gasification in a transport gasifier such as that being developed by Kellogg Brown and Root (KBR) was kinetically modeled. Char removed during the operation of a transport gasifier was collected, and the rate was determined using thermogravimetric analysis. Tests were performed in a simulated gasification environment containing a mixture of H 2 O, CO, CO 2 , H 2 , and N 2 . The steam gasification reaction rate for a North Dakota lignite at 815–950 °C can be estimated as d X/ d t=1.4×10 7 × e (−2.0×10 4 /T) ×P H 2 O 0.63 ×P Total −0.70 ×[ CO /( CO + CO 2 )] −1.91 . This rate law was used to predict the fraction of carbon steam gasified per minute based on steam concentration.