Simulated moving bed technology applied to coal gasification

Abstract

An alternative technology to conventional coal gasification is discussed in order to improve the performances of the existing processes. The concept of simulated moving bed (SMB) is applied to coal gasification: a number of fixed-bed reactors are connected in series and a suitable switching policy is applied so that each fixed-bed is cyclically operated both as a combustion and a gasification reactor. A possible combustion-gasification scheme is designed and simulated considering both chemical kinetics and mass-transfer phenomena. Sensitivity studies are carried out on a number of performance parameters: the syngas production efficiency, the H 2/CO molar ratio, the cold gas efficiency, the amount of CO 2 emitted per unit of syngas produced and the total productivity. The simulated performances of the newly proposed process are compared to those of conventional gasifiers.