Systems and processes for accelerated carbonation curing of pre-cast cementitious structures

Patent metadata

Field	Value
Publication number	US-11254028-B2
Application number	US-201916416384-A
Country	US
Kind code	B2
Filing date	May 20, 2019
Priority date	May 20, 2019
Publication date	Feb 22, 2022
Grant date	Feb 22, 2022

Abstract

Systems for accelerated carbonation curing of a pre-cast cementitious structure may include an ejector and a curing chamber downstream of the ejector. The ejector may be operable to combine a lesser-pressure carbon dioxide containing stream from a carbon dioxide source with a greater-pressure steam to produce a mixed stream including at least steam and carbon dioxide. The mixed stream may have a pressure greater than the pressure of the lesser-pressure carbon dioxide containing stream. The curing chamber may be operable to receive the mixed stream from the ejector and contact the mixed stream with the pre-cast cementitious structure to cure the pre-cast cementitious structure. Processes for accelerated carbonation curing of pre-cast cementitious structures using the systems are also disclosed.

First claim

What is claimed is:

1. A system for accelerated carbonation curing of a pre-cast cementitious structure, the system comprising:
an ejector operable to combine a lesser-pressure carbon dioxide containing stream from a carbon dioxide source with a greater-pressure steam to produce a mixed stream comprising at least steam and carbon dioxide and having a pressure greater than a pressure of the lesser-pressure carbon dioxide containing stream; and
a curing chamber downstream of the ejector, the curing chamber operable to receive the mixed stream from the ejector and contact the mixed stream with the pre-cast cementitious structure during curing of the pre-cast cementitious structure; where
the ejector comprises an inlet in fluid communication with a steam source, a nozzle in fluid communication with the inlet, a vacuum chamber in fluid communication with the carbon dioxide source, and a diffuser;
the nozzle is operable to convert the greater-pressure steam into a greater-velocity steam which produces a vacuum in the vacuum chamber; and
the vacuum is operable to draw the lesser-pressure carbon dioxide containing stream into the vacuum chamber and thereby causes mixing of the greater-velocity steam and the lesser-pressure carbon dioxide containing stream.

2. The system of claim 1 , in which the lesser-pressure carbon dioxide containing stream has a pressure of from 90 kilopascals (kPa) to 110 kPa.

3. The system of claim 1 , in which the greater-pressure steam has a pressure of from 150 kPa to 2000 kPa.

4. The system of claim 1 , in which the mixed stream has a pressure of from 150 kPa to 1500 kPa.

5. The system of claim 1 , in which the mixed stream comprises from 1 volume percent (vol. %) to 50 vol. % carbon dioxide based on the total volume flow rate of the mixed stream.

6. The system of claim 1 , further comprising the carbon dioxide source, wherein the carbon dioxide source comprises a hydrocarbon combustion process and the lesser-pressure carbon dioxide containing stream comprises at least a portion of combustion gases from the hydrocarbon combustion process.

7. The system of claim 1 , further comprising the steam source fluidly coupled to the ejector, the steam source comprising a steam system operable to produce the greater-pressure steam through combustion of a hydrocarbon fuel.

8. The system of claim 7 , wherein the lesser-pressure carbon dioxide containing stream comprises at least a portion of combustion gases resulting from the combustion of the hydrocarbon fuel in the steam system.

9. A process for accelerated carbonation curing of a pre-cast cementitious structure, the process comprising:
producing a greater-pressure steam,
passing the greater-pressure steam through an ejector having a nozzle and a vacuum chamber in fluid communication with a carbon dioxide source to receive a lesser-pressure carbon dioxide containing stream, the lesser-pressure carbon dioxide containing stream having a pressure less than a pressure of the greater-pressure steam, where passing the greater-pressure steam through the ejector combines the lesser-pressure carbon dioxide containing stream with the greater-pressure steam to produce a mixed stream comprising at least steam and carbon dioxide and having a pressure greater than a pressure of the lesser-pressure carbon dioxide containing stream; and
contacting the mixed stream with a pre-cast cementitious structure to conduct the accelerated carbonation curing of the pre-cast cementitious structure; where
the nozzle is configured to convert the greater-pressure steam into a greater-velocity steam which produces a vacuum in the vacuum chamber; and
the vacuum is configured to draw the lesser-pressure carbon dioxide containing stream into the vacuum chamber and thereby causes mixing of the greater-velocity steam and the lesser-pressure carbon dioxide containing stream.

10. The process of claim 9 , in which the lesser-pressure carbon dioxide containing stream has a pressure of from 90 kPa to 110 kPa.

11. The process of claim 9 , in which the greater-pressure steam has a pressure of from 150 kPa to 2000 kPa.

12. The process of claim 9 , in which the mixed stream has a pressure of from 150 kPa to 1500 kPa.

13. The process of claim 9 , in which the mixed stream comprises from 1 vol. % to 50 vol. % carbon dioxide based on the total volume flow rate of the mixed stream.

14. The process of claim 9 , comprising contacting the mixed stream with the pre-cast cementitious structure for from 1 hour to 8 hours.

15. The process of claim 9 , comprising passing the mixed stream to a curing chamber downstream of the ejector and contacting the mixed stream with the pre-cast cementitious structure within the curing chamber.

16. The process of claim 9 , further comprising passing the greater-pressure steam from a steam source to the ejector, wherein the steam source comprises a steam system configured to produce the greater-pressure steam through combustion of a hydrocarbon fuel.

17. The process of claim 16 , wherein the lesser-pressure carbon dioxide containing stream comprises at least a portion of combustion gases resulting from the combustion of the hydrocarbon fuel in the steam system.

18. A system for accelerated carbonation curing of a pre-cast cementitious structure, the system comprising:
an ejector comprising a nozzle operable to convert a greater-pressure steam into a greater velocity steam which produces a vacuum, where the vacuum draws a lesser-pressure carbon dioxide containing stream from a carbon dioxide source into the greater velocity steam to produce a mixed stream comprising at least steam and carbon dioxide and having a pressure greater than a pressure of the lesser-pressure carbon dioxide containing stream; and
a curing chamber downstream of the ejector, the curing chamber operable to receive the mixed stream from the ejector and contact the mixed stream with the pre-cast cementitious structure during curing of the pre-cast cementitious structure.

19. The system of claim 18 , wherein the ejector further comprises a vacuum chamber in fluid communication with the carbon dioxide source and a diffuser.

20. The system of claim 18 , wherein the ejector comprises an inlet in fluid communication with a steam source.

Assignees

• Saudi Arabian Oil Co

Inventors

• Jamal Aqil
• Fadhel Bandar A
• Amr Issam T

Classifications

• C04B40/024

  Steam hardening, e.g. in an autoclave · CPC title

• B01F25/31243

  Eductor or eductor-type venturi, i.e. the main flow being injected through the venturi with high speed in the form of a jet · CPC title

• B28B11/24 Primary

  for curing, setting or hardening (processes for influencing or modifying the setting or hardening ability of mortars, concrete or artificial stone compositions, in general C04B40/00) · CPC title

• B28B11/245 Primary

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

• C04B40/0231

  Carbon dioxide hardening · CPC title