This application relates to techniques, methods, and systems related to for producing carbon and net hydrogen liquid fuels, for example by anaerobic dissociation of hydrocarbons.
Methane concentration in the global atmosphere has more than doubled during the Industrial Revolution. A molecule of methane produces twenty to seventy times greater greenhouse warming and harmful stratospheric ozone destruction compared to a molecule of carbon dioxide. Increasingly large amounts of methane are released by erosion of soils that contain organic substances and from landfills, farm wastes, forest residues, and the fossil fuel industry. Much larger releases of methane are threatened by further greenhouse warming of vast permafrost and ocean bottom deposits of methane hydrates as ocean currents are modified.
Thermal dissociation of hydrocarbons (CxHy) such as methane to produce carbon and hydrogen provides attractive economic development opportunities. Illustratively anaerobic thermal dissociation of methane requires about 75 kJ/mole as shown by Equation 1.
CH4+Heat→C+2H2 (Heat=74.9 kJ/mole) Equation 1
Table 1 compares the thermal energy requirements for production of hydrogen by various approaches, one of which co-produces carbon (i.e. anaerobic dissociation1 of a hydrogen and carbon donor such as a hydrocarbon.)
1Anaerobic dissociation of hydrocarbons efficiently produce carbon and hydrogen.
2Requires about 3 times more combustion energy at the power plant to make the electricity required for electrolysis.
In addition to requiring the least amount of thermal energy per mole of hydrogen production, anaerobic dissociation of hydrocarbons such as methane can provide collection of carbon that may be utilized to make durable goods. It is highly desirable to produce hydrogen without releases of greenhouse gases such as CO2 or carbonaceous particulates and to co-produce valuable carbon.
Previous thermal dissociation efforts have been practiced as variously aerobic systems that wastefully burned the hydrogen to make carbon or burned the carbon to make hydrogen along with troublesome releases of greenhouse gases and particles. This has provided carbon black for purposes such as pigmentation, opacity, U.V. protection and as reinforcing filler in plastics and rubber products such as tires. In other instances it has provided hydrogen for chemical processes including production of ammonia and urea. However such wasteful processes have continued to be notorious sources of carcinogens, air and water pollution.
The present disclosure provides systems and methods for producing carbon and net hydrogen liquid fuels, for example by anaerobic dissociation of hydrocarbons. In some embodiments, the system and/or methods utilize concentrated solar energy. In some embodiments, the hydrocarbon comprises natural gas, propane, ethane, methane, or combinations thereof. In some embodiments the systems include electric resistance elements, induction heating susceptors, and/or flame radiation and/or conduction from combustion of a suitable fuel.
In one embodiment, the present technology provides a method of producing carbon and a net hydrogen liquid fuel, the method comprising providing a hydrocarbon, mixing an oxidant with the hydrocarbon to form a mixture, and combusting the mixture in the presence of hydrogen to form the carbon and the net hydrogen liquid fuel.
In another embodiment, the present technology provides a method of producing a net hydrogen liquid fuel, the method comprising providing a mixture of hydrogen and a hydrocarbon, anaerobically dissociating the hydrocarbon in the presence of heat and/or an oxidant to form carbon and the net hydrogen liquid fuel, and collecting and/or using the net hydrogen liquid fuel.
In yet another embodiment, the present technology provides a method of producing carbon and a net hydrogen liquid fuel, the method comprising providing a carbon donor substance, combining a hydrogen donor substance with the carbon donor source, and anaerobically dissociating the hydrocarbon in the presence of heat and/or an oxidant to form carbon and the net hydrogen liquid fuel.
In another embodiment, the present technology provides a method of producing carbon and a net hydrogen liquid fuel, the method comprising providing methane, combining an oxidant with the methane to form a mixture, and combusting the mixture in the presence of hydrogen to form carbon and the net hydrogen liquid fuel.
Various sources of heat and delivery systems are suitable for anaerobic dissociation of hydrocarbons such as concentrated solar energy, natural gas, propane, ethane or methane including systems with electric resistance elements, induction heating susceptors, and flame radiation and/or conduction from combustion of a suitable fuel.
Systems for producing a mixture of carbon and a net hydrogen liquid fuel are disclosed, for example, in U.S. patent application Ser. No. 14/290,789, attorney docket no. 69545-8408.US01, filed on May 29, 2014, and incorporated by reference in its entirety herein.
Various examples of methods for producing carbon and a net hydrogen liquid fuel will now be described in further detail. The following description provides specific details for a thorough understanding and enabling description of these examples. One skilled in the relevant art will understand, however, that the techniques discussed herein may be practiced without many of these details. Likewise, one skilled in the relevant art will also understand that the technology can include many other features not described in detail herein. Additionally, some well-known steps, structures or functions may not be shown or described in detail below so as to avoid unnecessarily obscuring the relevant description.
The terminology used below is to be interpreted in its broadest reasonable manner, even though it is being used in conjunction with a detailed description of some specific examples of the embodiments. Indeed, some terms may even be emphasized below; however, any terminology intended to be interpreted in any restricted manner will be overtly and specifically defined as such in this section.
Various urban legends suggest that the amount of energy that could possibly be supplied from biomaterials including organic wastes and energy crops is insufficient to replace present production of energy by fossil fuels. These legends are untrue but widely believed because of the myopic assumption that carbon in such feedstock materials is combusted one-time to produce energy.
Embodiments are disclosed for sustainable energy production that substantially exceeds one-time combustion of fossil fuels. Present embodiments provide for sustainable energy production by carbon-enhanced equipment. Carbon for reinforcing or otherwise enhancing the capabilities and performances of energy conversion equipment is extracted from organic wastes and energy crops and/or methane from decaying permafrost and/or oceanic deposits of clathrates (particularly methane hydrates) and/or from fossil fuels.
This allows cost-effective production and applications of carbon-reinforced or otherwise enhanced components and equipment to harness solar, wind, moving water, geothermal and other energy resources. Illustratively carbon reinforced wind and water turbines and/or other equipment such as ocean thermal energy conversion systems can harness far more than 1000 times the amount of energy produced by one-time sacrificial burning of such carbon. Carbon for enabling sustainable energy conversion practices is co-produced along with hydrogen from such carbon and hydrogen donor materials.
In many ways hydrogen is an ideal fuel that combusts in a wide range of air/fuel ratios, produces about three-times more heat per mass unit than petrol fuels such as gasoline, jet and diesel fuels. Hydrogen can be substituted for gasoline and diesel fuel by various combinations of the present embodiments to overcome production of carbon particles, carbon monoxide, carbon dioxide, oxides of nitrogen, and sulfur-based pollutants.
However the specific energy storage density (e.g. combustion mega-joules per volume or MJ/Liter) of gaseous hydrogen at ambient temperature and pressure is about 3,700 times lower than liquid diesel fuel and 3,400 times less than gasoline. Further, in comparison with liquid hydrocarbon fuel compounds, hydrogen molecules are much smaller and present far lower bulk viscosity to readily leak and escape through previously ignored defects that would not allow leakage of petrol fuels from fuel tanks.
The present embodiments facilitate the production of and applications of “net hydrogen liquid fuels” for sustainable economic development that otherwise will be increasingly lost as the growing vehicle production as shown is dedicated to fossil-sourced gasoline and diesel fuels. Typical processes for converting carbon donor substances such as CXHY including fossil and renewable compounds into valuable carbon based durable goods particularly include carbon-reinforced equipment. In the processes summarized “xC” depicts carbon enhanced equipment that delivers many times more energy than can be released by combustion, whereby the xC application provides sustainable conversion of solar, wind, moving water, and geothermal energy sources along with co-production of hydrogen.
As used herein, the term “hydrocarbon” refers to a compound having a general formula of CXHY. For example and without limitation, the term “hydrocarbon” as used herein includes, but is not limited to, methane, ethane, propane, butane, pentane, hexane, heptane, octane, nonane, and decane, in branched and/or unbranched configurations, or any other branched or unbranched compound of general formula CXHY, any combination thereof, or mixtures thereof, for example natural gas, fossil natural gas, waste digester gas, permafrost or landfill-sourced methane, or combinations thereof.
As used herein, the term “oxidant” refers to an element, compound, ion or radical capable of oxidizing a hydrocarbon. For example and without limitation, the term “oxidant” as used herein includes, but is not limited to, oxygen, ozone, NOX, OH−, air, an oxidizing exhaust gas, or a combination of any of the foregoing.
In various embodiments, the present technology provides methods for dissociating (e.g., anaerobically dissociating) a hydrocarbon. Equation 1A illustrates such a process.
CXHY +Heat→xC+(0.5y)H2 Equation 1A
Referring now to
In a variation shown in
As shown in the variation depicted in
Referring now to
In a similar embodiment shown in
Similarly, much less water vapor is released to the atmosphere upon combustion of such net hydrogen liquid fuels compared to combustion of fossil fuels to produce as much heat. Illustratively, each ton of hydrogen in a fossil fuel releases nine tons of water vapor in addition to the ambient moisture or humidity. Crop residue or organic waste sourced hydrogen that is incorporated in a net-hydrogen liquid fuel or hydrogen carrier fuel (HCF) release only as much water as the amount previously used by the green plants that sourced such wastes. In instances that organic wastes source hydrogen that is utilized to produce a durable good such as a thermoset or thermoplastic polymer the surface inventory of available water is actually reduced.
Referring now to
In a variation illustrated in
Referring now to
As shown in
As shown in
Referring now to
As shown in
As shown in
From the foregoing, it will be appreciated that specific embodiments of the invention have been described herein for purposes of illustration, but that various modifications may be made without deviating from the scope of the invention. Accordingly, the invention is not limited except as by the appended claims.
Filing Document | Filing Date | Country | Kind |
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PCT/US15/33361 | 5/29/2015 | WO | 00 |
Number | Date | Country | |
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62004802 | May 2014 | US |