ABSORPTION OF ATMOSPHERIC CARBON DIOXIDE

Abstract

A method, system and apparatus for the at least partial removal of carbon dioxide present in atmospheric air is disclosed. A hydroxide is distributed into atmospheric air. At least some of the carbon dioxide present in atmospheric air and the hydroxide react to form a carbonate compound, thereby at least partially removing carbon dioxide from the atmospheric air.

Claims

1. A method of at least partially removing carbon dioxide present in atmospheric air, the method comprising distributing a hydroxide into air in the atmosphere, such that the carbon dioxide and hydroxide react to form a carbonate compound, thereby at least partially removing carbon dioxide from the atmospheric air.

2. A method as claimed in claim 1 wherein the hydroxide is distributed into the atmospheric air as an aerosol.

3. A method as claimed in claim 1 wherein the hydroxide is present in an aqueous solution.

4. A method as claimed in claim 1 wherein the hydroxide is distributed into the atmospheric air at a location, selected such that the carbonate compound formed can be utilised.

5. A method as claimed in claim 1, wherein distributing the hydroxide comprises releasing the hydroxide into the atmospheric air at a height above ground level.

6. A method as claimed in claim 5 further comprising distributing a fluid into the atmospheric air, such that the fluid is at least partially modified.

7. A method as claimed in claim 6 wherein the fluid is a gas.

8. A method as claimed in claim 6 wherein the fluid is oxygen, and the oxygen is at least partially modified to form ozone.

9. A system of at least partially removing carbon dioxide present in atmospheric air, the system comprising a mechanism for delivering a hydroxide into air in the atmosphere, such that the carbon dioxide and the hydroxide react to form a carbonate compound, thereby at least partially removing carbon dioxide from the atmospheric air.

10. A system as claimed in claim 9 wherein the hydroxide comprises a compound that is stored in a receptacle, located in or on, the mechanism prior to delivery into the atmospheric air.

11. A system as claimed in claim 9 wherein the mechanism delivers the hydroxide into the atmospheric air above ground level.

12. A system as claimed in claim 11 further comprising a mechanism for delivering a fluid into the atmospheric air, such that the fluid is at least partially modified.

13. A system as claimed in claim 12 wherein the fluid is a gas.

14. A system as claimed in claim 12 wherein the fluid is oxygen, and the oxygen is at least partially modified to form ozone.

15. An apparatus for distributing a hydroxide and at least partially removing carbon dioxide present in atmospheric air, the apparatus configured to distribute the hydroxide into air in the atmosphere, such that the carbon dioxide and hydroxide react to form a carbonate compound, thereby at least partially removing carbon dioxide from the atmospheric air.

16. An apparatus as claimed in claim 15 configured to distribute the hydroxide into the atmospheric air at a height above ground level.

17. An apparatus as claimed in claim 16 configured to distribute a fluid into the atmospheric air, such that the fluid is at least partially modified.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Notwithstanding any other forms that may fall within the scope of the method, system and apparatus for the conversion of carbon dioxide as set forth in the Summary, specific embodiments will now be described, by way of example only, with reference to the accompanying drawings in which:

[0042] FIG. 1 shows a schematic overview of a first embodiment;

[0043] FIG. 2 shows a general flow chart of the method; and

[0044] FIG. 3 shows a schematic overview of a second embodiment.

DETAILED DESCRIPTION

[0045] Referring firstly to FIG. 1, a general schematic overview of an embodiment for at least partially removing carbon dioxide from atmospheric air is shown. As previously mentioned, the system can be employed to reduce carbon dioxide levels currently present in atmospheric air in an effort to counteract, for example, industrial carbon emissions. In this regard, the system can be considered as providing for the conversion of carbon dioxide (i.e. the chemical conversion or reaction of carbon dioxide) into another, less environmentally damaging, form. It should also be appreciated that the levels of carbon dioxide can be monitored and the amount of carbon dioxide removed from the atmospheric air can be controlled, such as by controlling the amount of calcium hydroxide being distributed into the atmospheric air. Removing carbon dioxide from the atmosphere too quickly, or removing it altogether, is not recommended. Monitoring of atmospheric carbon dioxide levels can also assist with determining whether distribution of calcium hydroxide should be limited or ceased if atmospheric carbon dioxide levels are reduced to a specified level.

[0046] In this embodiment, an aeroplane, shown as 12, distributes calcium hydroxide, shown as aerosolised calcium hydroxide particles 10, into the air at a height well above the ground. In this regard, the aeroplane 12 may be configured to release the calcium hydroxide particles 10 at a specific height above the ground (although, it is not so limited). By releasing, or distributing, the calcium hydroxide particles 10 at a greater height, the particles 10 have additional time to react with carbon dioxide 14 present in the air. At least some of the carbon dioxide 14 present in the air and the released calcium hydroxide particles 10 react to form a calcium carbonate compound and water, collectively shown as ‘16’. This thereby at least partially removes some of the carbon dioxide, which was present in the air, therefrom. As calcium hydroxide is highly reactive to carbon dioxide, when the calcium hydroxide is released at a considerable height above the ground, it is unlikely that significant quantities of calcium hydroxide will fall to the earth, as it will be converted to calcium carbonate and water.

[0047] It can be seen in FIG. 1 that, even though there is some carbon dioxide remaining in the atmosphere, some of the carbon dioxide has been removed from the atmosphere, by converting the carbon dioxide into another form. It can also be seen that some of the calcium hydroxide particles may not react with the carbon dioxide. The unreacted particles may just fall to the earth. This is more likely if the carbon dioxide levels are lower where calcium hydroxide is distributed. Although, in most circumstances, it is hypothesised that negligible quantities of calcium hydroxide will reach the earth.

[0048] The amount of calcium hydroxide being distributed into the atmosphere can be adjusted according to the levels of carbon dioxide present in the atmosphere. For example, if the carbon dioxide levels in the atmosphere are reduced as a result of the implementation of the method, system and apparatus disclosed herein, such as to pre-Industrial Revolution levels, the amount of calcium hydroxide distributed may need to be reduced (i.e. to prevent too much carbon dioxide being removed from the atmosphere).

[0049] The reaction between calcium hydroxide and carbon dioxide is shown by the following equation:

Ca(OH).sub.2+CO.sub.2.fwdarw.CaCO.sub.3+H.sub.2O

[0050] The formed calcium carbonate (CaCO.sub.3) will slowly settle to earth in relatively small concentrations, due to the small droplet size used in aerosolising the aqueous calcium hydroxide.

[0051] Even though, in this embodiment, distribution or delivery of the calcium hydroxide has been described as being released by an aeroplane, it will be appreciated that there are many ways in which the calcium hydroxide can be distributed into the atmospheric air, which can be dependent on the location at which the carbon dioxide is to be removed, its form (liquid or solid), etc.

[0052] In this regard, a generic flow chart is shown in FIG. 2, outlining the general or generic steps which can lead to the at least partial removal of carbon dioxide from atmospheric air. An apparatus or delivery mechanism, such as an aeroplane, is shown at 20. Distribution of a calcium hydroxide into atmospheric air occurs at 22. The calcium hydroxide reacts with carbon dioxide present in the air at 24, and the resulting calcium carbonate compound, which is formed in the reaction at 24, is shown at 26. This simplified process is what enables the method and system disclosed herein to have such wide and varied applications.

[0053] For example, by using calcium hydroxide, the resulting calcium carbonate compound can be used for other purposes, and can enable further benefit to be obtained (i.e. the reduction of carbon dioxide levels in the atmosphere may not be the only benefit obtained from employing the disclosed method or system).

[0054] Further, the state of the calcium hydroxide compound can be altered, for example it may be distributed as a solid particulate, or it may be an aqueous solution.

[0055] FIG. 2 also outlines the general or generic, optional, steps which can lead to the at least partial modification of a fluid, such as oxygen, in atmospheric air. The apparatus or delivery mechanism 20 can be further configured to distribute a fluid into atmospheric air, shown at 28. The fluid is at least partially modified by reacting with a substance (such as a chemical substance or compound) present in the air, or is otherwise modified by components of the environment (such as UV radiation) at 30, and the resulting modified fluid, is shown at 32.

[0056] Referring now to FIG. 3, a general schematic overview of a second embodiment for at least partially removing carbon dioxide from atmospheric air is shown. In this second embodiment, an aeroplane 40 is configured to distribute a calcium hydroxide, shown as aerosolised calcium hydroxide particles 10, and a fluid, shown as oxygen molecules 42. FIG. 3 generally depicts the flight path of aeroplane 40, with positions A and E being the aeroplane 40 on the ground, and positions B, C and D being the aeroplane 40 in-flight. As shown in FIG. 3, the calcium hydroxide particles 10 and oxygen molecules 42 are distributed at different locations/position during the flight of aeroplane 40. For example, when the aeroplane 40 is in the vicinity of positions B and D, calcium hydroxide particles 10 are distributed into the air, whereas oxygen molecules 42 are distributed into the air when the aeroplane 40 is in the vicinity of position C. At positions B and D, as before, when the calcium hydroxide particles 10 are distributed into the air at least some of the carbon dioxide 14 present in the air reacts with the calcium hydroxide particles 10 to form a calcium carbonate compound and water, collectively shown as ‘16’. At position C, the oxygen molecules 42 are distributed into the air. In this embodiment, they are shown as being distributed in an upwardly direction (i.e. towards the stratosphere) in an effort to improve the likelihood of ozone formation at the correct location. The oxygen molecules 42 may be photolyzed by UV light (hv.sub.uv) and split into two oxygen atoms, 44. An oxygen atom 44 may then combine with an oxygen molecule 42 to form ozone (O.sub.3), 46.

[0057] In this embodiment, it is possible to both reduce carbon dioxide levels present in atmospheric air (or, at least, partially offset any carbon dioxide emissions generated by the aeroplane) and assist in the replenishment of the Earth's ozone layer.

[0058] The disclosed embodiments can allow a variety of methods and systems to be employed. Additionally, little new equipment may be required. For example, a simple tank with a nozzle for creating a fine mist may be mounted into a commercial aeroplane. Once the aeroplane is at an appropriate altitude, or located over an appropriate agricultural field, the calcium hydroxide can be released as a fine mist.

[0059] The amount of calcium hydroxide and, optionally, fluid loaded into the container/tank can also be varied depending on the specific requirements of the aircraft. For example, it may be necessary to include additional weight on the aircraft so that it has an even weight distribution. In such cases, additional calcium hydroxide and, optionally, fluid can be loaded onto the flight. Alternatively, where an aircraft is not fully loaded, such as when all seats on the aircraft have not been sold, it may be possible to load calcium hydroxide and, optionally, fluid onto the aircraft for distribution into the atmosphere mid-flight. In a further example, when pilots are training it may be necessary to load additional ‘dead’ weight into the aeroplane. This ‘dead weight’ could be provided by loading calcium hydroxide and, optionally, fluid into the aircraft, which could then be distributed prior to landing. Previously, the additional loading of weight into aircraft was only increasing the carbon dioxide emissions of the aircraft. However, with the presently disclosed method and system, it is possible to utilise this required additional weight to assist with the removal of carbon dioxide from the atmosphere (both their own emitted carbon dioxide, as well as the carbon dioxide emitted by others).

[0060] Space craft may also be a viable option for dispersing calcium hydroxide and, optionally, fluid into the atmosphere at a higher altitude than aeroplanes. Again, suitable ratios of calcium hydroxide and, optionally, fluid could allow the additional reduction of carbon dioxide in the atmosphere and, optionally, assist in replenishing of the Earth's ozone layer. Other vehicles, such as cars, trucks, tractors, etc can also be employed to distribute the calcium hydroxide. Utilisation of such vehicles that contribute to carbon dioxide emissions can provide a simple way to offset their own emissions, as well as providing additional removal of carbon dioxide from the atmosphere.

[0061] The calcium hydroxide may also be distributed from a boat or other water-travelling vehicle, into the air. An alternative form of moving object, such as the blades or vanes of a wind turbine or windmill, etc, may be used to distribute the calcium hydroxide.

[0062] Dispersal of the calcium hydroxide from a stationary position, such as a building or structure, is also a viable embodiment. In this regard, the calcium hydroxide can be stored at an appropriate location on, or in, the building or structure and released therefrom. In such embodiments, it may be preferable to utilise a propelled aerosol to achieve appropriate dispersion of the calcium hydroxide. Alternatively, the calcium hydroxide need not be stored near to the building or structure from which it will be dispersed. For example, the calcium hydroxide may be stored some distance away and transported to the dispersal location, such as by pipes or gravity feeding to the site.

[0063] The calcium carbonate compound poses no significant danger to people and animals, and can be readily utilised for other purposes. The resulting calcium carbonate can be used as a fertiliser to improve, for example, agricultural crop quality or to strengthen the shells of marine organisms.

EXAMPLE

[0064] A non-limiting Example of the carbon dioxide conversion method and system will now be described, with reference to FIG. 2.

[0065] 17.3 grams of calcium hydroxide, which is soluble in water up to 1.73 g/L, was mixed with water to form 10 Litres of aqueous calcium hydroxide solution. Some of the solution was then put into a spray bottle.

[0066] In order to confirm that carbon dioxide present in atmospheric air was reacting with the calcium hydroxide, the solution was sprayed into the air as a fine mist through a nozzle, over a large plastic sheet. The sheet was allowed to dry in the sun to evaporate the water, and a crystalline substance remained on the plastic sheet.

[0067] To determine whether the crystalline substance was calcium carbonate, a small amount of the crystalline substance was collected. Hydrochloric acid was added to the crystalline substance, and gas bubbles were observed to rapidly effervesce.

[0068] It was understood that the calcium carbonate and hydrochloric acid reacted to give calcium chloride and carbon dioxide, according to the following equation:

CaCO.sub.3+2HCl.fwdarw.CaCl.sub.2+CO.sub.2+H.sub.2O

[0069] The potential applications for this simple method and system are significant, and can be used to reduce the carbon dioxide levels in the atmosphere, and theoretically begin to reverse some of the adverse effects of carbon dioxide as a greenhouse gas.

[0070] It will be understood to persons skilled in the art that many other modifications may be made without departing from the spirit and scope of the method, system and apparatus as disclosed herein.

[0071] In the claims which follow and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations thereof such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the method, system and apparatus for the conversion of carbon dioxide.