Chemical Engineering & Technology, Vol.35, No.3, 497-507, 2012
Carbon Stripping - A Critical Process Step in Chemical Looping Combustion of Solid Fuels
In chemical looping combustion of solid fuels the well-mixed solids flow from the fuel reactor consisting of char, ash, and oxygen carrier particles cannot be completely separated into its constituents before it enters the air reactor. The slip of carbon will thus lead to char oxidation in the wrong reactor. Process simulation was applied to investigate the carbon stripping process in chemical looping combustion of solid fuels. Depending on the fuel choice, without carbon stripping CO2 capture rates below 50?% are calculated for 4?min of solids residence time in the fuel reactor. In a process with carbon stripper, however, CO2 capture rates exceeding 90?% can be achieved for both fuels investigated in this work.