Method and system for capturing and purifying carbon dioxide

A system for capturing and purifying carbon dioxide, wherein the system for capturing and purifying the carbon dioxide comprises:

• a carbon dioxide capture device, provided with an alkaline solution inlet, a target component inlet, and a discharging port for an aqueous solution containing carbonate;
• an oxygen purification device, provided with a crude oxygen inlet, an inlet for an aqueous solution containing carbonate, a discharging port for an aqueous solution containing bicarbonate, and an oxygen discharging port, the inlet for an aqueous solution containing carbonate being in communication with the discharging port for an aqueous solution containing carbonate;
• an electrolysis unit, provided with an inlet for an aqueous solution containing bicarbonate, an anode gas discharging port, a hydrogen outlet, and a regenerated alkaline solution discharging port, and the inlet for an aqueous solution containing bicarbonate being in communication with the discharging port for an aqueous solution containing bicarbonate through a delivery pipeline for an aqueous solution containing bicarbonate;
• a carbon dioxide separation device, provided with an anode gas inlet, a liquid carbon dioxide outlet, and a crude oxygen outlet, the anode gas inlet being in communication with the anode gas discharging port through an anode gas delivery pipeline, and the crude oxygen outlet being in communication with the crude oxygen inlet through a crude oxygen delivery pipeline;
• a carbon dioxide detection device, configured to determine a content of carbon dioxide in the crude oxygen delivery pipeline;
• and
• a valve, disposed on the crude oxygen delivery pipeline and located downstream of the carbon dioxide detection device, the valve being disposed in linkage with the carbon dioxide detection device, and when the content of the carbon dioxide reaches a preset value, the valve being opened.