CO 2 separation and recovery equipment comprising: a CO shift reactor into which a gas containing main components of CO and H 2 O is introduced to convert the gas into CO 2 and H 2; an inlet valve provided on an inlet side of the CO shift reactor; an outlet valve provided on an outlet side of the CO shift reactor; a steam control valve adapted to apply high-temperature steam to a foregoing part of the inlet valve; a gas composition analyzer adapted to sense a gas composition of a stream flowing into the CO shift reactor; an absorption tower, a regeneration tower and a distillation tower through which the CO 2 is passed and recovered; wherein the CO 2 separation and recovery equipment is characterized by a CO shift reaction controller which is adapted to calculate a total amount of temperature energy necessary for a catalytic reaction in the CO shift reactor from the molar amount of CO that is calculated from analysis results of the gas composition analyzer and temperature energy necessary for the catalytic reaction; and the CO shift reaction controller adapted to control the steam control valve by a difference in molar amount of CO and H 2 O that is calculated from on-line analysis results of the gas composition analyzer, and, when energy determined on the basis of a catalyst tank temperature of the CO shift reactor is deviated from an upper limit energy or a lower limit energy, to control the inlet valve and the outlet valve of the CO shift reactor on the basis of the catalyst tank temperature of the CO shift reactor, by controlling the inlet valve to be opened and by controlling simultaneously the outlet valve to be closed so that the inside of the CO shift reactor is in a pressurized state and the catalyst tank temperature is raised, when the energy determined on the basis of the catalyst tank temperature is lower than the total amount of the temperature energy necessary for the catalytic reaction, and by controlling the inlet valve to be opened and simultaneously by controlling the outlet valve to be opened so that the inside of the reactor is in a depressurized state and the catalyst tank temperature is lowered, when the energy determined on the basis of the catalyst tank temperature is higher than temperature energy for hindering the catalytic reaction. a CO shift reactor into which a gas containing main components of CO and H 2 O is introduced to convert the gas into CO 2 and H 2; an inlet valve provided on an inlet side of the CO shift reactor; an outlet valve provided on an outlet side of the CO shift reactor; a steam control valve adapted to apply high-temperature steam to a foregoing part of the inlet valve; a gas composition analyzer adapted to sense a gas composition of a stream flowing into the CO shift reactor; an absorption tower, a regeneration tower and a distillation tower through which the CO 2 is passed and recovered; wherein the CO 2 separation and recovery equipment is characterized by a CO shift reaction controller which is adapted to calculate a total amount of temperature energy necessary for a catalytic reaction in the CO shift reactor from the molar amount of CO that is calculated from analysis results of the gas composition analyzer and temperature energy necessary for the catalytic reaction; and the CO shift reaction controller adapted to control the steam control valve by a difference in molar amount of CO and H 2 O that is calculated from on-line analysis results of the gas composition analyzer, and, when energy determined on the basis of a catalyst tank temperature of the CO shift reactor is deviated from an upper limit energy or a lower limit energy, to control the inlet valve and the outlet valve of the CO shift reactor on the basis of the catalyst tank temperature of the CO shift reactor, by controlling the inlet valve to be opened and by controlling simultaneously the outlet valve to be closed so that the inside of the CO shift reactor is in a pressurized state and the catalyst tank temperature is raised, when the energy determined on the basis of the catalyst tank temperature is lower than the total amount of the temperature energy necessary for the catalytic reaction, and by controlling the inlet valve to be opened and simultaneously by controlling the outlet valve to be opened so that the inside of the reactor is in a depressurized state and the catalyst tank temperature is lowered, when the energy determined on the basis of the catalyst tank temperature is higher than temperature energy for hindering the catalytic reaction.