Cementitious print head, 3D printing architecture, and cementitious printing methodology

Patent metadata

Field	Value
Publication number	US-11236517-B2
Application number	US-201916724790-A
Country	US
Kind code	B2
Filing date	Dec 23, 2019
Priority date	Dec 23, 2019
Publication date	Feb 1, 2022
Grant date	Feb 1, 2022

Abstract

A cementitious print head and a cementitious printing methodology may include a feed barrel, a print head nozzle, a CO2 supply, a steam supply, a selective valve assembly in communication with the CO2 supply and the steam supply, a plurality of dual use extrusion head injectors, and a print head controller. The print head controller is operatively coupled to the selective valve assembly and is programmed to execute a CO2 and steam injection protocol where steam may be selected for injection by the extrusion head injectors into a cementitious composition as it is extruded from the print head nozzle to enhance a hydration reaction and formation of hydroxide in the cementitious composition before CO2 may be selected for injection by the extrusion head injectors into the cementitious composition as it is extruded from the print head nozzle to enhance a carbonation reaction in the cementitious composition.

First claim

What is claimed is:

1. A print head for extruding a cementitious composition, the print head comprising a feed barrel, a print head nozzle, a CO2 supply, a steam supply, a selective valve assembly in communication with the CO2 supply and the steam supply, a plurality of dual use extrusion head injectors, and a print head controller, wherein:
the feed barrel is oriented and shaped to receive the cementitious composition and to direct the cementitious composition to the print head nozzle;
the selective valve assembly communicatively couples the CO2 supply and the steam supply to the dual use extrusion head injectors for selective injection of CO2 and steam from individual ones of the extrusion head injectors;
the plurality of dual use extrusion head injectors are positioned downstream of the print head nozzle for selective injection of CO2 and steam into the cementitious composition extruded from the print head nozzle; and
the print head controller is operatively coupled to the selective valve assembly and is programmed to execute a CO2 and steam injection protocol where steam is exclusively selected for injection by the extrusion head injectors into the cementitious composition as it is extruded from the print head nozzle to enhance a hydration reaction and formation of hydroxide in the cementitious composition before CO2 is exclusively selected for injection by the extrusion head injectors into the cementitious composition as it is extruded from the print head nozzle to enhance a carbonation reaction in the cementitious composition.

2. The print head for extruding a cementitious composition of claim 1 , wherein the print head controller is programmed to execute the CO 2 and steam injection protocol to establish an alternating and repeating sequence of steam and CO 2 injection into the cementitious composition.

3. The print head for extruding a cementitious composition of claim 2 , wherein the alternating and repeating sequence of steam and CO 2 injection into the cementitious composition comprises periods of steam injection in the sequence that are larger than periods of CO 2 injection in the sequence, at approximately equal steam and CO 2 flow rates.

4. The print head for extruding a cementitious composition of claim 3 , wherein the periods of steam injection are between approximately 3 and approximately 5 times larger than the periods of CO 2 injection.

5. The print head for extruding a cementitious composition of claim 4 , wherein the periods of steam injection are approximately 2.0 minutes.

6. The print head for extruding a cementitious composition of claim 4 , wherein the periods of CO 2 injection are approximately 0.5 minutes.

7. The print head for extruding a cementitious composition of claim 3 , wherein the periods of steam injection are approximately 2.0 minutes, at a flow rate of approximately 10 ml/min, and the periods of CO 2 injection are approximately 0.5 minutes, at a flow rate of approximately 10 ml/min.

8. The print head for extruding a cementitious composition of claim 2 , wherein the alternating and repeating sequence of steam and CO 2 injection comprises a series of injection-free periods of duration in the alternating and repeating sequence of steam and CO 2 injection.

9. The print head for extruding a cementitious composition of claim 8 , wherein the duration of individual ones of the injection-free periods is between approximately 0 sec and approximately 20 sec.

10. The print head for extruding a cementitious composition of claim 8 , wherein the duration of individual ones of the injection-free periods is less than approximately 10 sec.

11. The print head for extruding a cementitious composition of claim 2 , wherein the alternating and repeating sequence of steam and CO 2 injection comprises a series of steam injection periods of duration t H2O , a series of CO 2 injection periods of duration t CO2 , and a series of injection-free periods of duration t 0 , satisfying the following relations, at FWHM:
t H2O ≥t CO2 ≥t 0 ;

0 sec≤t H2O ≤180 sec;

0 sec≤t CO2 ≤60 sec; and

0 sec≤t 0 ≤20 sec.

12. The print head for extruding a cementitious composition of claim 3 , wherein the periods of steam injection and the periods of CO 2 injection are characterized by approximately equal flow rates.

13. The print head for extruding a cementitious composition of claim 2 , wherein:
the dual use extrusion head injectors are positioned to selectively inject CO 2 and steam into the cementitious composition downstream of the print head nozzle; and
the dual use extrusion head injectors are positioned to selectively inject CO 2 and steam into the cementitious composition from positions that at least partially surround an extruded column of cementitious composition.

14. The print head for extruding a cementitious composition of claim 2 , wherein the selective valve assembly comprises independent valve assembly components dedicated to respective ones of the CO 2 supply and the steam supply, or an integrated valve assembly unit in communication with the CO 2 supply and the steam supply.

15. The print head for extruding a cementitious composition of claim 2 , wherein the CO 2 supply and the steam supply comprise pressurized gas containers, pressurized supply lines, or a combination thereof.

16. A 3D printing architecture comprising a 3D print head positioning framework and the print head of claim 1 , wherein the print head is mounted to the 3D positioning framework for 3D movement of the print head nozzle.

17. The 3D printing architecture of claim 16 , wherein:
the 3D printing architecture further comprises a source of cementitious material in communication with the feed barrel of the print head; and
the extruded cementitious composition and the CO 2 and steam injection protocol are configured such that the extruded cementitious composition is self-supporting at NTP.

18. The print head for extruding a cementitious composition of claim 1 , further comprising an extrusion head injector cover positioned around the plurality of dual use extrusion head injectors to minimize the loss of CO 2 and steam to the atmosphere.

19. The print head for extruding a cementitious composition of claim 18 , further comprising a screed bar positioned downstream of the extrusion head injector cover and the print head nozzle to form the cementitious composition.

20. A print head for extruding a cementitious composition, the print head comprising a feed barrel, a print head nozzle, a CO2 supply, a steam supply, a selective valve assembly in communication with the CO2 supply and the steam supply, a plurality of extrusion head injectors, and a print head controller, wherein:
the feed barrel is oriented and shaped to receive the cementitious composition and to direct the cementitious composition to the print head nozzle;
the selective valve assembly communicatively couples the CO2 supply and the steam supply to the extrusion head injectors for selective injection of CO2 and steam from the extrusion head injectors;
the extrusion head injectors are positioned downstream of the print head nozzle for selective injection of CO2 and steam into the cementitious composition extruded from the print head nozzle; and
the print head controller is operatively coupled to the selective valve assembly and is programmed to execute a CO2 and steam injection protocol where steam is selected for injection by the extrusion head injectors into the cementitious composition as it is extruded from the print head nozzle to enhance a hydrati

Assignees

• Saudi Arabian Oil Co

Inventors

• Al-Khowaiter Ahmad O
• Jamal Aqil
• Amr Issam T
• Bamagain Rami
• Al-Hunaidy Ali Shakir
• Fadhel Bandar A

Classifications

• B33Y80/00

  Products made by additive manufacturing · CPC title

• B33Y50/02

  for controlling or regulating additive manufacturing processes · CPC title

• B28B17/0081

  Process control · CPC title

• B28B11/245

  Curing concrete articles (B28B11/242 takes precedence) · CPC title

• C04B2111/00181

  Mixtures specially adapted for three-dimensional printing (3DP), stereo-lithography or prototyping · CPC title