Thermodynamic Analysis\nof Optimal Performance of Three\nModes of Operation of Autothermal Chemical Looping Gasification

Abstract

A chemical looping gasification process comprising of\nfuel and\nair reactors (FR and AR) is thermodynamically analyzed under autothermal\nconditions. The analysis takes into account the incomplete carbon\nconversion in the FR. Depending on how the unburnt carbon in the FR\nis processed, 3 modes of operation are analyzed viz. (1) sending unburnt\ncarbon to the AR, (2) removal of unburnt carbon from the process,\nand (3) recycle of unburnt carbon to the FR. Autothermal operating\nconditions are identified for each mode of operation. It has been\nshown that, for optimal performance, while mode 1 and mode 2 have\nto be operated with minimum flow of oxygen carrier (OC) and medium\nair flow, mode 3 has to be operated with maximum OC flow and minimum\nair flow. Performance results for mode 1 of operation at the optimal\noperation point are generalized to any solid fuel.