A system used for converting multiple fuel feedstocks may include three reactors. The reactor system combination can be so chosen that one of the reactors completely or partially converts the fuel while the other generates the gaseous product required by utilizing the gaseous product from the second reactor. The metal-oxide composition and the reactor flow-patterns can be manipulated to provide the desired product. A method for optimizing the system efficiency where a pressurized gaseous fuel or a pressurized utility is used for applications downstream can be used to any system processing fuels and metal-oxide.

A fixed bed reactor for desulfurization is provided, the fixed bed reactor including an outlet collector that is located at a lower end portion of the fixed bed reactor; and a lower baffle that is formed spaced apart from an upper portion of the outlet collector. The fixed bed reactor efficiently lowers a surface temperature of the outlet collector located at a lower end portion of the fixed bed reactor.