Red mud-based perovskite oxygen carrier preparation for chemical looping gasification of municipal sludge.

Chemical looping gasification (CLG) is a promising technology that utilizes lattice oxygen for partial oxidation of solid organic waste to produce high-quality syngas. The utilization of low-cost and high-performance oxygen carriers (OCs) is important for the success of this technology. The red mud from aluminum production was mixed with calcium and manganese oxides to prepare CaMnFeO perovskite OCs.

Investigation on the Chemical-Looping Reaction Characteristics of Ningdong Coal with Manganese Ore.

In order to explore an efficient and clean conversion way of Ningdong coal, the chemical-looping reaction of Ningdong coal was conducted in a laboratory-scale fluidized-bed reactor using manganese ore as the oxygen carrier (OC), and the reaction characteristics were investigated in combination by thermogravimetric analysis. Experiments included the investigation of the reaction of the manganese ore with 5 vol % H and with coal powder at 900 °C, the catalytic and OC effect of manganese ore on coal gasification, the reaction efficiency and reaction products under different mass ratios of OC to coal (O/C), and the effect of multiple cycles on the reaction performance of the manganese ore. At 900 °C, the OC exhibited higher reactivity with coal syngas, significantly reducing the time of coal gasification (∼48% reduction).