Abstract: According to the components of calcium carbide residue and the composition of flue gas，a process route of pressurized carbonization was proposed.Utilization of calcium carbide residue and the technology of carbon dioxide capture and storage from flue gas were integrated in the process.The environmental problems from calcium carbide residue and flue gas were solved，and the high-value added nano-sized calcium carbonate was produced.The parameters of this process were investigated.The optimum technical conditions were as follows：calcination temperature was 900 ℃，lime-water mass ratio was 1∶7，carbonation pressure was 0.4 MPa，and gas velocity of flue gas was 0.093 m/s.Under these conditions，adding crystallization controlling agent，a spherical nano-sized calcium carbonate with narrow diameter distribution was prepared and the particle size was 60 nm.

Key words: calcium carbide residue, flue gas, calcium carbonate