Design and Experimental Testing of a 1.9MWth Calcium Looping Pilot Plant

Calcium looping (CaL) CO2 capture process using calcium oxide as a regenerable solid sorbent has been under development at the Industrial Technology Research Institute (ITRI) of Taiwan for several years. At 2013, the 1.9MWth pilot plant has been fully constructed, and the trial runs have been progressed for almost one year. The CO2 was captured by CaO from the flue gas of the cement plant in a bubbling fluidized-bed carbonator while diesel oil oxy-combustion in the rotary kiln provides the heat required to regenerate the sorbent. The start-up progress of carbonator does not use pre-heating system, but take advantage of heat dissipated by the hot sorbent form the calciner. The flow rate of the flue gas from the stack of the cement plant was 3400 Nm3/h with the CO2 concentration higher than 15 vol%. The test results showed the CO2 capture efficiency higher than 85% for 7 hours and the CO2 concentration of the outlet gas was under 2%. The accumulated time of unit operation test in this pilot plant is more than 600 hours, and that for the fully-continuous looping test is more than 300 hours, respectively. The CO2 capture rate higher than 1 t/h was obtained, which reached the design point of this pilot plant. It is considered as an important milestone for the future construction of a 30 MWth demonstration plant.