Solar calcination at pilot scale in a continuous flow multistage horizontal fluidized bed

•High quality lime was processed in a continuous flow pilot-scale solar fluidized bed.•Feedstock mass flow rate varied in the range 14.5–25 kg/h and mean solar power was 55 kW.•Calcite mass flow rate of 20 kg/h resulted in a degree of conversion of 95.2%•Thermochemical and thermal efficiency of the reactor reached 17% and 29% respectively.