A carbon dioxide recovery apparatus (6,7) comprising: an absorption tower which introduces therein carbon dioxide-containing gas and brings the carbon dioxide-containing gas into contact with an absorbing liquid for absorbing carbon dioxide to generate a first rich liquid having absorbed the carbon dioxide, and, thus, to discharge the first rich liquid; a heat exchanger which heats the first rich liquid; a flow divider which divides the first rich liquid heated by the heat exchanger into a second rich liquid and a third rich liquid; a first carbon dioxide release device which heats the second rich liquid and thereby discharges a first semi-lean liquid in which carbon dioxide-containing steam is released; a second carbon dioxide release device which heats the third rich liquid and thereby discharges a second semi-lean liquid in which carbon dioxide-containing steam is released; and a regeneration tower which heats the first semi-lean liquid and the second semi-lean liquid to release remaining carbon dioxide-containing steam, and, thus, to generate a lean liquid and thereby returns the lean liquid to the absorption tower, wherein the first carbon dioxide release device heats the second rich liquid, using the lean liquid discharged from the regeneration tower as a heat source, the second carbon dioxide release device heats the third rich liquid, using the carbon dioxide-containing steam generated at the regeneration tower as a heat source, and the heat exchanger heats the first rich liquid, using the lean liquid which has passed through the first carbon dioxide release device as a heat source, the second carbon dioxide release device is a first packed bed provided in the regeneration tower at a position higher than a position where the first semi-lean liquid is supplied to the regeneration tower, and a portion of the first rich liquid is divided between the absorption tower and the heat exchanger; wherein the portion of the first rich liquid is supplied to the second carbon dioxide release device, or wherein the portion of the first rich liquid is supplied to a third carbon dioxide release device, provided in the regeneration tower at a higher position than the second carbon dioxide release device, wherein said third carbon dioxide release device is a second packed bed which heats the portion of the first rich liquid using the carbon-dioxide steam generated at the regeneration tower as a heat source and thereby discharges a third semi-lean liquid in which carbon-dioxide containing steam is released, and the regeneration tower, in order to release remaining carbon-dioxide containing steam and thus generate the lean liquid, further heats the third semi-lean liquid. an absorption tower which introduces therein carbon dioxide-containing gas and brings the carbon dioxide-containing gas into contact with an absorbing liquid for absorbing carbon dioxide to generate a first rich liquid having absorbed the carbon dioxide, and, thus, to discharge the first rich liquid; a heat exchanger which heats the first rich liquid; a flow divider which divides the first rich liquid heated by the heat exchanger into a second rich liquid and a third rich liquid; a first carbon dioxide release device which heats the second rich liquid and thereby discharges a first semi-lean liquid in which carbon dioxide-containing steam is released; a second carbon dioxide release device which heats the third rich liquid and thereby discharges a second semi-lean liquid in which carbon dioxide-containing steam is released; and a regeneration tower which heats the first semi-lean liquid and the second semi-lean liquid to release remaining carbon dioxide-containing steam, and, thus, to generate a lean liquid and thereby returns the lean liquid to the absorption tower, wherein the first carbon dioxide release device heats the second rich liquid, using the lean liquid discharged from the regeneration tower as a heat source, the second carbon dioxide release device heats the third rich liquid, using the carbon dioxide-containing steam generated at the regeneration tower as a heat source, and the heat exchanger heats the first rich liquid, using the lean liquid which has passed through the first carbon dioxide release device as a heat source, the second carbon dioxide release device is a first packed bed provided in the regeneration tower at a position higher than a position where the first semi-lean liquid is supplied to the regeneration tower, and a portion of the first rich liquid is divided between the absorption tower and the heat exchanger; wherein the portion of the first rich liquid is supplied to the second carbon dioxide release device, or wherein the portion of the first rich liquid is supplied to a third carbon dioxide release device, provided in the regeneration tower at a higher position than the second carbon dioxide release device, wherein said third carbon dioxide release device is a second packed bed which heats the portion of the first rich liquid using the carbon-dioxide steam generated at the regeneration tower as a heat source and thereby discharges a third semi-lean liquid in which carbon-dioxide containing steam is released, and the regeneration tower, in order to release remaining carbon-dioxide containing steam and thus generate the lean liquid, further heats the third semi-lean liquid.