A method for capturing carbon dioxide from air to obtain a food grade C02. The method comprises the individual steps of first, exposing a sorbent to a carbon dioxide-containing gas selected from the group consisting of ambient air and an ambient air - effluent gas blend, so as to enable said sorbent to capture carbon dioxide from said carbon dioxide-containing gas flow so as to form CO2-laden sorbent. The sorbent is supported upon a porous support structure. The CO2-laden sorbent is next exposed to co-generated steam at a temperature of less than about 120°C. The steam was formed by co-generated process heat from a primary production process to co-generate the steam superheated at ambient pressure. The steam strips the CO2 from the sorbent, thus regenerating the sorbent, in a sealed regeneration chamber. The regeneration chamber was first pumped out, to remove most of any remaing air or any other gas entering the sealed regeneration chamber with the CO2 laden sorbent to form at least a partial vacuum. The thus stripped and captured carbon dioxide from the sorbentm forming a carbon dioxide/water exiting mixture. By flowing substantially pure CO2 into the pumped out chamber, before regeneration by steam, remaining gaseous or volatile liquid impurities are removed.
展开▼
