US-20260124573-A1 - SYSTEM AND METHOD FOR PRESSURIZED DIRECT AIR CAPTURE OF CARBON DIOXIDE

US20260124573A1US 20260124573 A1US20260124573 A1US 20260124573A1US-20260124573-A1

Abstract

A method for CO2 DAC includes a. filtering an atmospheric air stream comprising carbon dioxide to remove therefrom at least one impurity, selected from the group consisting of debris, dust, water droplets, mist, particulate matter, and combinations thereof, wherein such impurities are detrimental to a subsequent compressing step; b. compressing the atmospheric air stream comprising carbon dioxide to form a compressed atmospheric air stream with a throughput rate of least one billion cubic meters of the atmospheric air stream annually, wherein the compressing step achieves a volume reduction of at least 50% as compared to the incoming atmospheric air stream, so as to enable a subsequent separating step to handle a volumetric capacity smaller than that of a subsequent separating step without said compressing step; and c. separating at least a portion of the carbon dioxide from the compressed atmospheric air stream to form a stream with reduced carbon content

Inventors

Ahmed Mohamed Nasereidin Mohamed Elsayed
Thaier Tawfeek Alawadh

Dates

Publication Date: 20260507
Application Date: 20251229

Claims (16)

1 . A high-pressure method for capturing dilute carbon dioxide directly from the atmosphere, comprising the following steps: a. filtering an atmospheric air stream comprising carbon dioxide to remove therefrom at least one impurity, selected from the group consisting of debris, dust, water droplets, mist, particulate matter, and combinations thereof, wherein such impurities are detrimental to a subsequent compressing step; b. compressing the atmospheric air stream comprising carbon dioxide to form a compressed atmospheric air stream with a throughput rate of least one billion cubic meters of the atmospheric air stream annually, wherein the compressing step achieves a volume reduction of at least 50% as compared to the incoming atmospheric air stream, so as to enable a subsequent separating step to handle a volumetric capacity smaller than that of a subsequent separating step without said compressing step; and c. separating at least a portion of the carbon dioxide from the compressed atmospheric air stream to form a stream with reduced carbon content.
2 . The high-pressure method of claim 1 wherein the separating step comprises gas absorption and/or gas membrane separation.
3 . The high-pressure method of claim 1 wherein the separating step is performed in a pressurized absorption zone, and wherein the separating step comprises: a. introducing the compressed atmospheric air stream and a lean solvent stream into the pressurized absorption zone; b. contacting the compressed atmospheric air stream with the lean solvent stream to absorb at least a portion of the carbon dioxide from the compressed atmospheric air stream; and c. generating a rich solvent stream comprising the portion of the carbon dioxide and an air stream with reduced carbon dioxide content.
4 . The high-pressure method of claim 3 wherein the separating step is further performed in a heat exchange zone and a stripping zone, and wherein the separating step further comprises: a. introducing the rich solvent stream and the lean solvent stream into the heat exchange zone; b. thermally contacting the rich solvent stream with the lean solvent stream to transfer thermal energy from the lean solvent stream to the rich solvent stream; c. introducing the rich solvent stream into the stripping zone; and d. generating the lean solvent stream by removing at least a portion of carbon dioxide from the rich solvent stream.
5 . The high-pressure method of claim 3 wherein the separating step is further performed in a pressure exchange zone, a heat exchange zone, and a stripping zone, and wherein the separating step further comprises: a. introducing the rich solvent stream and the lean solvent stream into the pressure exchange zone; b. transferring pressure energy from the rich solvent stream to the lean solvent stream; c. introducing the rich solvent stream and the lean solvent stream into the heat exchange zone; d. thermally contacting the rich solvent stream with the lean solvent stream to transfer thermal energy from the lean solvent stream to the rich solvent stream; e. introducing the rich solvent stream into the stripping zone; and f. generating the lean solvent stream by removing at least a portion of carbon dioxide from the rich solvent stream.
6 . The high-pressure method of claim 3 wherein the compressing step further comprises: a. introducing the air stream with reduced carbon dioxide content into an expansion zone; b. expanding the air stream with reduced carbon dioxide content to generate mechanical power; and c. recovering the mechanical power generated to at least partially compress the atmospheric air stream comprising carbon dioxide.
7 . The high-pressure method of claim 6 wherein the separating step is further performed in a heat exchange zone and a stripping zone, and wherein the separating step further comprises: a. introducing the rich solvent stream and the lean solvent stream into the heat exchange zone; b. thermally contacting the rich solvent stream with the lean solvent stream to transfer thermal energy from the lean solvent stream to the rich solvent stream; c. introducing the rich solvent stream into the stripping zone; and d. generating the lean solvent stream by removing at least a portion of carbon dioxide from the rich solvent stream.
8 . The high-pressure method of claim 6 wherein the separating step is further performed in a pressure exchange zone, a heat exchange zone, and a stripping zone, and wherein the separating step further comprises: a. introducing the rich solvent stream and the lean solvent stream into the pressure exchange zone; b. transferring pressure energy from the rich solvent stream to the lean solvent stream; c. introducing the rich solvent stream and the lean solvent stream into the heat exchange zone; d. thermally contacting the rich solvent stream with the lean solvent stream to transfer thermal energy from the lean solvent stream to the rich solvent stream; e. introducing the rich solvent stream into the stripping zone; and f. generating the lean solvent stream by removing at least a portion of carbon dioxide from the rich solvent stream.
9 . The method of claim 8 wherein the lean solvent stream comprises water and at least one component selected from the group consisting of about 4 moles to about 6 moles of ammonia per liter of water, about 3 moles to about 5 moles of potassium carbonate per liter of water, about 1 mole to about 3 moles of sodium carbonate per liter of water, and combinations thereof.
10 . The method of claim 8 wherein the pressurized absorption zone is operated at a pressure at a point in a range of about 50 bar to about 80 bar and a temperature at a point in a range of about 5° C. to about 60° C.
11 . The method of claim 8 wherein the stripping zone is operated a pressure at a point in a range of about 1 bar to about 3 bar and a temperature at a point in a range of about 90° C. to about 140° C.
12 . The high-pressure method of claim 1 , wherein the compressing step further comprises: a. introducing the air stream with reduced carbon dioxide content into an expansion zone; b. expanding the air stream with reduced carbon dioxide content to generate mechanical power; and c. recovering the mechanical power generated to at least partially compress the atmospheric air stream comprising carbon dioxide; and wherein the separating step is performed in a gas membrane zone, and wherein the separating step comprises: a. introducing the compressed atmospheric air stream into the gas membrane zone; b. separating at least a portion of the carbon dioxide from the compressed atmospheric air stream; and c. generating a carbon dioxide rich stream and an air stream with reduced carbon dioxide content.
13 . The high-pressure method of claim 12 wherein the separating step is further performed in a heat exchange zone, and wherein the separating step further comprises: a. introducing the compressed atmospheric air stream and the air stream with reduced carbon dioxide content into the heat exchange zone; b. thermally contacting the compressed atmospheric air stream with the air stream with reduced carbon dioxide content; and c. transferring thermal energy from the compressed atmospheric air stream to the air stream with reduced carbon dioxide content.
14 . The high-pressure method of claim 12 wherein the gas membrane zone operates at a pressure at a point in a range of about 50 bar to about 300 bar, and at a temperature at a point in a range of about ambient temperature to about 150° C.
15 . A high-pressure method for capturing dilute carbon dioxide directly from the atmosphere, comprising the following steps: a. filtering an atmospheric air stream comprising carbon dioxide to remove therefrom large debris, coarse dust, water droplets, mist, and very fine particulate matter, wherein such impurities are detrimental to a subsequent compressing step; b. compressing the atmospheric air stream comprising carbon dioxide to form a compressed atmospheric air stream, wherein the compressing step achieves a volume reduction of at least 98% as compared to the incoming atmospheric air stream, so as to enable a subsequent separating step to handle a volumetric capacity smaller than that of a subsequent separating step without said compressing step; c. introducing the compressed atmospheric air stream into a pressurized absorption zone; d. introducing a lean solvent stream into the pressurized absorption zone wherein the lean solvent stream comprises water and about 4 moles to about 6 moles of ammonia per liter of water, about 3 moles to about 5 moles of potassium carbonate per liter of water, and about 1 mole to about 3 moles of sodium carbonate per liter of water; e. operating the pressurized absorption zone at a pressure at a point in a range of about 50 bar to about 80 bar and a temperature at a point in a range of about 5° C. to about 60° C.; f. contacting the compressed atmospheric air stream with the lean solvent stream to absorb at least a portion of the carbon dioxide from the compressed atmospheric air stream; g. generating a rich solvent stream comprising the portion of the carbon dioxide and an air stream with reduced carbon dioxide content; h. introducing the rich solvent stream and the lean solvent stream into a pressure exchange zone; i. transferring pressure energy from the rich solvent stream to the lean solvent stream; j. introducing the rich solvent stream and the lean solvent stream into a heat exchange zone; k. thermally contacting the rich solvent stream with the lean solvent stream to transfer thermal energy from the lean solvent stream to the rich solvent stream; l. introducing the rich solvent stream into a stripping zone; m. operating the stripping zone at a pressure at a point in a range of about 1 bar to about 3 bar and a temperature at a point in a range of about 90° C. to about 140° C.; n. generating the lean solvent stream by removing at least a portion of carbon dioxide from the rich solvent stream; and o. expanding the air stream with reduced carbon dioxide content to recover mechanical power and at least partially compress the atmospheric air stream comprising carbon dioxide.
16 . A high-pressure method for capturing dilute carbon dioxide directly from the atmosphere, comprising the following steps: a. filtering an atmospheric air stream comprising carbon dioxide to remove therefrom large debris, coarse dust, water droplets, mist, and very fine particulate matter, wherein such impurities are detrimental to a subsequent compressing step; b. compressing the atmospheric air stream comprising carbon dioxide to form a compressed atmospheric air stream, wherein the compressing step achieves a volume reduction of at least 98% as compared to the incoming atmospheric air stream, so as to enable a subsequent separating step to handle a volumetric capacity smaller than that of a subsequent separating step without said compressing step; c. introducing the compressed atmospheric air stream into a gas membrane zone; d. operating the gas membrane zone at a pressure at a point in a range of about 50 bar to about 300 bar, and at a temperature at a point in a range of about ambient temperature to about 150° C. e. separating at least a portion of the carbon dioxide from the compressed atmospheric air stream; f. generating a carbon dioxide rich stream and an air stream with reduced carbon dioxide content. g. introducing the compressed atmospheric air stream and the air stream with reduced carbon dioxide content into a heat exchange zone; h. thermally contacting the compressed atmospheric air stream with the air stream with reduced carbon dioxide content; i. transferring thermal energy from the compressed atmospheric air stream to the air stream with reduced carbon dioxide content. j. introducing the air stream with reduced carbon dioxide content into an expansion zone; k. expanding the air stream with reduced carbon dioxide content to generate mechanical power, and l. recovering the mechanical power generated to at least partially compress the atmospheric air stream comprising carbon dioxide.

Description

CROSS-REFENCE TO RELATED APPLICATIONS This application is a divisional application of U.S. Non-Provisional application Ser. No. 18/955,610 filed Nov. 21, 2024 which claims priority to U.S. Provisional Application 63/603,102 filed Nov. 27, 2023, the disclosures of which are incorporated by reference in their entirety. FIELD This disclosure relates to a direct air capture (DAC) of carbon dioxide, and more particularly to a high-pressure DAC system designed to separate carbon dioxide. BACKGROUND Carbon dioxide capture, or simply carbon capture, is a process which removes carbon dioxide (CO2) from various gas streams. A common application of carbon capture is to remove CO2 from natural gas and post-combustion streams at power plants. Direct Air Capture (DAC) is a specific form of carbon capture technology that involves capturing CO2 directly from the atmosphere, rather than from industrial or power plant sources. This makes DAC a promising technology for mitigating climate change, as it has the potential to remove CO2 from the atmosphere. However, capturing carbon dioxide from dilute carbon dioxide streams can be challenging, as the concentration of CO2 in the gas stream may be extremely low, which makes it more expensive to capture. To overcome this challenge, various methods have been proposed for capturing CO2 from dilute gas streams, such as gas absorption, gas adsorption, gas membranes, and electrochemical methods, among others. Unfortunately, current methods are not optimized for capturing CO2 from dilute gas streams and are often inefficient and costly. Some low-pressure direct air capture systems use large industrial fans to capture CO2 at or near atmospheric pressure. Since the concentration of CO2 in the air is low, CO2 capturing methods which operate at atmospheric pressure may require large amounts of energy to capture CO2. Additionally, these methods have relatively slow CO2 sorption rates and lower CO2 sorption capacity and may require larger sorption contact area. Sorption refers to both adsorption and absorption. At the heart of conventional low-pressure DAC, or atmospheric DAC systems is a contact structure or “contactor”, configured for CO2 sorption. A noticeable feature of these systems is that they often contain large fans which are integral to their design and operation. These fans draw in ambient air and channel the air to the contactor where a portion of the carbon dioxide is removed from the air. The contactor includes a CO2 capture medium such as liquid absorption with a strong base such as Group I or Group II hydroxides and/or solid adsorption with weak bases such as an amine-based material. In some embodiments, the CO2 capture medium includes a metal hydroxide such as potassium hydroxide (KOH) or other solvents which effectively trap the CO2 molecules. The prevailing approach to scaling DAC technology has been to increase the number of fans, operating under the principle that more fans would lead to greater air processing capacity and, consequently, higher CO2 capture rates. However, this strategy alone is insufficient for achieving CO2 removal on a gigaton scale. SUMMARY The present disclosure includes, in some embodiments, a system for capturing CO2 from dilute gas streams using an aqueous absorption method. The pressure of the diluted CO2 gas stream is raised before being introduced to the aqueous solution. The system is composed of several components, including absorption and stripping columns, aqueous pressure and pneumatic pressure equipment, and a heat recovery unit. The air intake subsystem is responsible for bringing in the air stream, and it is designed to remove certain particles and any drag from air flow layers. The air intake subsystem compresses the incoming air to high pressures and feeds it into the absorption column. The absorption column is the key component of the system, which takes in a lean aqueous solution from the top of the column and enriches it with CO2 from the air as it goes down the column. The absorption column operates at high-pressures and relatively ambient temperatures, and the absorbent used can come from materials such as sodium carbonate, potassium carbonate, ammonia, or any combination of these. In embodiments of the present disclosure, a gas separation system of the CO2 capture system operates at high-pressure. For example, a gas separation system operates at pressures at a point in a range between 10 bar-300 bar. In some embodiments, a gas separation system includes an aqueous absorption component which operates at pressures at a point in a range between 10 bar-50 bar. In some embodiments, a gas separation system includes an aqueous absorption component which operates at pressures at a point in a range between 50 bar-80 bar. In some embodiments, a gas separation system includes a polymer separation membrane which operates at pressures at a point in a range between 50 bar-120 bar. In some embodiments, a gas separation system includes a metal se