Dimensioning Air Reactor and Fuel Reactor of a Pressurized Chemical Looping Combustor to Be Coupled to a Gas Turbine: Part 1, the Air Reactor

This paper provides a simple methodology for the design of the air reactor of a chemical looping combustor to optimize its characteristics when it is employed connected to a turbo expander to produce power. The design process, given a certain objective (e.g., electric power) defines the reactor specifics, namely height and diameter, taking into account the following aspects: solids inventory of the air reactor; gas velocity; air reactor transport disengaging height (TDH); solids concentration profile along the reactor height, dense bed height; freeboard height; pressure drop depending on air reactor injectors design and configuration. The total air reactor height was about 9.5 m, while the diameter was about 1.8 m. The total inventory was about 10,880 kg; while the circulation rate in the air reactor was about 110 kg/s. The operating pressure and temperature were, respectively, 12 bar and 1200 degrees C. The average velocity of the gases inside the reactor was about 4 m/s. The fluidization regime resulted to be comprised between turbulent and fast fluidization. Further work must be directed into the estimate of the pressure drop of the reactor, which will affect the plant efficiency in a considerable way.

Automated summary

This paper presents a simple methodology to optimize the design of the air reactor in a chemical looping combustor when connected to a turbo expander for power production. Considerations such as solid inventory, gas velocity, transport disengaging height, and pressure drop are taken into account. The reactor in this study had a height of 9.5 m and a diameter of 1.8 m, with a total inventory of 10,880 kg and a circulation rate of 110 kg/s. The operating pressure and temperature were 12 bar and 1200 degrees C, respectively, with an average gas velocity of 4 m/s. The fluidization regime was found to be between turbulent and fast fluidization. Further work is needed to estimate the reactor's pressure drop, which will significantly affect plant efficiency.