Attachment design and methodology for direct carbonation of thixotropic cementitious composite fluids

A system comprising:

• an additive manufacturing printer;
• a printhead attached to the additive manufacturing printer, wherein the additive manufacturing printer is configured to flow a primary fluid comprising a cementitious material through the printhead while moving the printhead, wherein the printhead comprises:
• a main body comprising:
• a first inlet configured to receive the primary fluid;
• an outlet nozzle, wherein the first inlet and the outlet nozzle are located at opposing ends of the main body, wherein the main body defines an inner bore extending from the first inlet to the outlet nozzle, wherein the inner bore comprises a convergent-divergent section and a shearing section;
• a shearing blade disposed within the shearing section of the inner bore;
• a pressure chamber surrounding at least a portion of the inner bore,
• wherein the pressure chamber is configured to house a secondary fluid;
• and
• a secondary inlet extending from the pressure chamber to the convergent-divergent section of the inner bore for transferring the secondary fluid from the pressure chamber to the inner bore, wherein the shearing blade is configured to provide shear force onto the primary fluid and the secondary fluid, thereby promoting mixing of and interaction between the primary fluid and the secondary fluid to produce a cementitious composite material, wherein the outlet nozzle is configured to discharge the cementitious composite material;
• and
• a regulator device coupled to the pressure chamber of the main body for providing the secondary fluid to the pressure chamber.

A method comprising:

• flowing a primary fluid comprising a cementitious material into an inner bore of a printhead;
• flowing a secondary fluid comprising carbon dioxide, steam, or both into a pressure chamber surrounding at least a portion of the inner bore of the printhead;
• flowing the secondary fluid from the pressure chamber into the inner bore of the printhead while the primary fluid flows within the inner bore of the printhead to mix the secondary fluid with the primary fluid within the inner bore of the printhead and form a cementitious composite material;
• and
• discharging the cementitious composite material from the inner bore of the printhead.