We've many times documented that Coal, along with many and various sorts of naturally Carbon-recycling biological material, can be "gasified", in a process of partial oxidation or limited combustion, and be converted thereby into a blend of, primarily, Carbon Monoxide and Hydrogen, that is, a hydrocarbon synthesis gas, or "syngas", which can then be catalytically, chemically condensed, as via the long-known and still-practiced Fischer-Tropsch process, into gaseous and liquid hydrocarbon fuels and chemicals.
As we've seen, for one example, in:
Texaco Coal to Synthetic Fuels and Electrical Power | Research & Development | News; concerning, in part: "United States Patent 4,099,383 - Partial Oxidation Process; 1978; Inventors: Peter Paull, CT, and Rodney McGann, CA; Assignee: Texaco, Inc., NY; Abstract: Sensible heat in the hot effluent gas stream leaving a partial oxidation gas generator for the production of gaseous mixtures comprising H2 +CO, i.e. synthesis gas, reducing gas, or fuel gas, is used at maximum temperature to heat a stream of heat transfer fluid preferably comprising a portion of the product gas circulating in a substantially closed loop. The heat transfer fluid serves as the working fluid in a turbine that produces mechanical work, electrical energy, or both. Further, the heat transfer fluid leaving the turbine may be used to preheat hydrocarbonaceous feed and free-oxygen containing gas which is then introduced into the gas generator. Optionally, by-product superheated steam may be produced at high temperature levels for use in the gas generator and as the working fluid in an expansion turbine. The high steam superheat temperatures results in higher conversion efficiencies. Summary: At a great economic benefit, a portion of the synthesis gas may be used as said heat transfer fluid. Some of said synthesis gas may be introduced into the aforesaid loop of heat transfer fluid as make-up and to replace leakage from for example seals and flanges. The remainder of the synthesis gas may be reacted over a catalyst to produce chemicals. For example, a stream of of synthesis gas having a mole ratio (H2 /CO) in the range of about 2 to 12 and at a temperature in the range of about 400 to 750 F may be passed through a chamber containing methanol catalyst to synthesize methanol";
the processes for Coal gasification have become so sophisticated that they can be made to generate useful amounts of co-product electricity, along with hydrocarbon synthesis gas. And, again, as seen for one example in:
California 2012 Coal and Carbon-Recycling Waste to Syngas | Research & Development | News; concerning the presentation: "Production of Synthetic Fuels from Carbonaceous Matter Using Steam Hydrogasification; Joseph M. Norbeck; Director of Environmental Research Institute; University of California Riverside; April, 2008", wherein a "Thermo Chemical Process for Production of Synthetic Hydrocarbon Fuels" is illustrated as: "Carbon > Syngas Generation > H2 + CO > Fuel Process > Liquids > Upgrading > Clean Liquid Fuels", it's further demonstrated that, via the intermediate production of synthesis gas, via "gasification", "Any carbonaceous material can be converted ... into synthetic fuel: Biomass; Wood (and) forest clearings; Crop waste, agricultural residues; Energy crops (switchgrass, corn stover); Animal (and) municipal solid waste, food waste, biosolids; Plastic (PVC, PUF)–Polymers (rubber, tires); Coal (and) mine tailings";
the high Carbon and high latent energy content of Coal, and the quantities in which Coal can be made available, enables the inclusion and productive consumption of a wide variety of renewable and Carbon-recycling wastes and purpose-grown agricultural products in such gasification processes - - which, by the way, are becoming even increasingly sophisticated and efficient, as we will soon be reporting.
As we've many times documented, some Carbon Dioxide is co-produced during the hydro-gasification of carbonaceous materials; and, even though the inclusion of, as in the University of California presentation cited above, "Biomass; Wood (and) forest clearings; Crop waste, agricultural residues; Energy crops (switchgrass, corn stover); Animal (and) municipal solid waste, food waste, biosolids" with Coal in the gasification might represent a process that indirectly recycles more Carbon Dioxide than it might produce, as seen in:
USDOE CO2 + Hydrogen = Methanol and Ethanol | Research & Development | News; concerning: "United States Patent 7,858,667 - Alcohol Synthesis from CO or CO2; 2010; Assignee: Battelle Memorial Institute, WA; (United States Department of Energy; Pacific Northwest National Laboratory); Abstract: Methods for producing alcohols from CO or CO2 and H2 utilizing a palladium-zinc (Pd--Zn) on alumina catalyst are described. Methods of synthesizing alcohols over various catalysts in microchannels are also described. Ethanol, higher alcohols, and other C2+ oxygenates can be produced utilizing Rh--Mn (Rhodium and Manganese) or a Fisher-Tropsch catalyst. A method of synthesizing alcohols from CO or CO2 comprising: flowing a reactant gas mixture comprising H2 and CO or CO2 into contact with a catalyst; wherein the catalyst comprises a Pd--Zn alloy dispersed on alumina; and forming an alcohol or alcohols";
Carbon Dioxide in hydrocarbon synthesis gas can still be reacted with Hydrogen in a Fischer-Tropsch, or related, hydrocarbon synthesis reaction, although the result will be the production of more "oxygenated hydrocarbons", or alcohols, rather than the typical hydrocarbons which might be more desired. Or, as in:
France Efficient CO2 to Carbon Monoxide Conversion | Research & Development | News; concerning: "United States Patent Application 20030113244 - Method for Producing Carbon Monoxide by Reverse Conversion with an Adapted Catalyst; 2003; Assignee: Air Liquide (France); The invention concerns a method for producing carbon monoxide by reverse conversion, in gas phase, of carbonic acid gas and gaseous hydrogen while minimising the production of methane. The invention is characterised in that the reaction is carried out at a temperature between 300 and 520 C and under pressure between 10 to 40 bars in the presence of an iron-free catalyst based on zinc oxide and chromium oxide. Said method is preferably carried out continuously and comprises preferably the following steps which consist in: a) preparing a gas mixture rich in carbon dioxide and in hydrogen ... between 300 and 520 C; b) reacting said gas mixture, forming carbon monoxide and water vapour, by passing said mixture through a catalytic bed based on zinc oxide and chromium oxide maintained under pressure between 10 and 40 bars";
the reverse water gas shift reaction between Carbon Dioxide and Hydrogen can be catalyzed for, which would reduce the Carbon Dioxide and form more of the desired Carbon Monoxide, but which would also consume Hydrogen, perhaps necessitating a supplemental supply of additional Hydrogen for the subsequent Fischer-Tropsch synthesis of hydrocarbons.
The United States Department of Energy has a solution to the issue of the Carbon Dioxide content of hydrocarbon synthesis gas generated from Coal, as we documented in:
USDOE Converts Coal and CO2 into Hydrocarbon Syngas | Research & Development | News; concerning: "United States Patent Application 20090235587 - Methods and Systems for Producing Syngas; 2009; Inventors: Grant Hawkes, James Obrien, Carl Stoots, et. al., Idaho; Assignee: Battelle Energy Alliance, LLC, Idaho Falls; Government Interests: The United States Government has certain rights in this invention pursuant to Contract No. DE-AC07-05-ID14517, between the US Department of Energy and Battelle Energy Alliance, LLC (USDOE Idaho National Laboratory); Abstract: Methods and systems are provided for producing syngas utilizing heat from thermochemical conversion of a carbonaceous fuel to support decomposition of at least one of water and carbon dioxide using one or more solid-oxide electrolysis cells. Simultaneous decomposition of carbon dioxide and water or steam by one or more solid-oxide electrolysis cells may be employed to produce hydrogen and carbon monoxide. A portion of oxygen produced from at least one of water and carbon dioxide using one or more solid-oxide electrolysis cells is fed as a controlled flow rate in a gasifier or combustor to oxidize the carbonaceous fuel to control the carbon dioxide to carbon monoxide ratio produced";
wherein the heat energy generated by the Coal gasification process is harnessed to drive the conversion, or "decomposition", of Carbon Dioxide, and perhaps added Water vapor, into Carbon Monoxide and additional Hydrogen, with Oxygen as a by-product which can then be used to support the partial-oxidation gasification process, and actually help thereby "to control the carbon dioxide to carbon monoxide ratio produced" in that Coal gasification process.
And, herein, we document that technical experts in the United States Government's Patent and Trademark Office confirmed the validity of "United States Patent Application 20090235587", as seen, with comment inserted and appended, in excerpts from the initial link in this dispatch to:
"United States Patent 8,366,902 - Methods and Systems for Producing Syngas
Patent US8366902 - Methods and systems for producing syngas - Google Patents
Methods and systems for producing syngas - Battelle Energy Alliance, LLC
Date: February 5, 2013
Inventors: Grant Hawkes, et. al., Idaho
Assignee: Battelle Energy Alliance, LLC, Idaho Falls
Abstract: Methods and systems are provided for producing syngas utilizing heat from thermochemical conversion of a carbonaceous fuel to support decomposition of at least one of water and carbon dioxide using one or more solid-oxide electrolysis cells. Simultaneous decomposition of carbon dioxide and water or steam by one or more solid-oxide electrolysis cells may be employed to produce hydrogen and carbon monoxide. A portion of oxygen produced from at least one of water and carbon dioxide using one or more solid-oxide electrolysis cells is fed at a controlled flow rate in a gasifier or combustor to oxidize the carbonaceous fuel to control the carbon dioxide to carbon monoxide ratio produced.
(Note that this represents an additional use for the heat generated by the Coal gasification. Which, as seen in our above-cited report concerning: "United States Patent 4,099,383 - Partial Oxidation Process", can also be used to generate the electricity needed by the "solid-oxide electrolysis cells".)
Government Interests: This invention was made with government support under Contract Number DE-AC07-05ID14517 awarded by the United States Department of Energy. The government has certain rights in the invention.
Claims: A method for forming syngas, comprising: producing heat and a mixed gas comprising carbon dioxide, carbon monoxide, water and hydrogen by gasifying a carbonaceous fuel; condensing the mixed gas to remove at least one impurity from the mixed gas and to generate a feed stream; after the condensing act, transferring the heat produced by gasifying the carbonaceous fuel to the feed stream to convert at least a portion of the water in the feed stream to steam; introducing the feed stream to at least one solid-oxide electrolysis cell; electrolyzing carbon dioxide and steam in the feed stream in at least one solid-oxide electrolysis cell to produce carbon monoxide, hydrogen and oxygen; and separating the carbon monoxide and hydrogen from the oxygen.
The method ... further comprising transferring heat from the carbon monoxide, hydrogen and oxygen produced in the at least one solid-oxide electrolysis cell to the feed stream.
The method ... further comprising contacting the mixed gas with a water stream having a temperature substantially lower than a temperature of the mixed gas to cool the mixed gas.
The method ... wherein producing heat and a mixed gas comprising carbon dioxide, carbon monoxide, water and hydrogen by gasifying a carbonaceous fuel comprises gasifying the carbonaceous fuel in the presence of a portion of the oxygen formed by electrolyzing carbon dioxide and steam to control a ratio of carbon monoxide and hydrogen produced by electrolyzing the carbon dioxide and the steam.
(Note, that, as seen in our report of:
Utah 2011 CO2 + H2O = Hydrocarbon Syngas | Research & Development | News; concerning: "United States Patent 8,075,746 - Electrochemical Cell for Production of Synthesis Gas Using Atmospheric Air and Water; 2011; Inventors: Joseph Hartvigsen, et. al., Utah; Assignee: Ceramatec, Inc., Salt Lake City; Abstract: A method is provided for synthesizing synthesis gas from carbon dioxide obtained from atmospheric air or other available carbon dioxide source and water using a sodium-conducting electrochemical cell. Synthesis gas is also produced by the coelectrolysis of carbon dioxide and steam in a solid oxide fuel cell or solid oxide electrolytic cell. The synthesis gas produced may then be further processed and eventually converted into a liquid fuel suitable for transportation or other applications";
the USDOE and its contractors have designed the necessary equipment with which to effect "electrolyzing the carbon dioxide and the steam".)
Background and Field: Embodiments of the present invention relate, generally, to the production of syngas and, more particularly, to methods and systems for producing syngas from a carbonaceous fuel, such as biomass (and) coal ... by utilizing the heat from thermochemical conversion of the carbonaceous fuel to support electrolysis of steam and/or co-electrolysis of steam and carbon dioxide in one or more solid-oxide electrolysis cells.
As energy consumption in the United States and throughout the world continues to increase, additional methods for environmentally clean energy conversion that can convert biomass (and) coal to hydrogen, synthetic fuels and chemicals are desired. Concerns about the increased wastes and pollutants produced by many of the conventional energy conversion processes, and the low efficiencies of such processes, have led to further research for cleaner, more efficient processes.
In response to the increasing energy demands and the desire to reduce or eliminate pollutants, new cleaner, energy conversion processes that can utilize biomass (and) coal ... are being sought.
A known process for conversion of these energy resources to cleaner fuels includes synthetic fuels, often referred to as "synfuels," which are made from synthesis gas, often referred to as "syngas." Syngas includes a mixture of varying amounts of carbon monoxide (CO) and hydrogen (H2) that may be converted to form hydrogen, synfuels, methanol or chemicals. Production of synfuels from syngas may be performed using a variety of processes including a Fischer-Tropsch process to convert the carbon monoxide and hydrogen into liquid hydrocarbons.
The synfuels produced using the Fischer-Tropsch process may include high purity, low sulfur, fuels, often referred to as "Fischer-Tropsch liquids," which have fewer pollutants than naturally occurring fuels or fuels processed from naturally occurring oil deposits.
Another approach is to convert syngas into methanol, which may be converted to gasoline, olefins, or aromatics. Syngas may be converted to methanol using a copper or zinc catalyst such as a modified ZSM-5 catalyst.
(For a little more information on the above, see, for only one example, our report of:
ExxonMobil "Coal to Clean Gasoline" | Research & Development | News; concerning: "Coal to Clean Gasoline; Xinjin Zhao, Ron D. McGihon and Samuel A. Tabak; ExxonMobil Research and Engineering Company, USA, discuss ExxonMobil's methanol to gasoline technology for the production of clean gasoline from coal".)
High temperature solid-oxide fuel cells may be used to produce electricity and water from hydrogen and oxygen (O2). When run in reverse, the solid-oxide fuel cells are called solid-oxide electrolysis cells and are able to electrolytically reduce and split water into hydrogen and oxygen and carbon dioxide into carbon monoxide and oxygen. The water may be converted into hydrogen, which may be combined with carbon monoxide to form syngas. In a solid-oxide electrolysis cell, the anode is the reducing gas electrode and the cathode is the oxidant-side electrode. When operated in reverse, as a solid-oxide electrolysis cell, the anode is the oxidant-side electrode and the cathode is the reducing gas electrode. Furthermore the solid-oxide electrolysis cell may be used to co-electrolyze a mixture of water and carbon dioxide to produce syngas.
Improvements to systems and processes for producing syngas are continually sought after by various industries. It would be beneficial to develop efficient systems and methods of producing syngas while minimizing carbon emissions.
Summary: Various embodiments of the present invention include methods and systems for producing hydrogen or syngas by employing thermochemical conversion of a carbonaceous fuel to produce heat to support one or more solid-oxide electrolysis cells. By utilizing heat produced during the thermochemical conversion of the carbonaceous fuel, an external heat source is not needed in the methods and systems.
According to various embodiments, configurations of the systems may utilize one or more solid-oxide electrolysis cells that are integrated with the gasification system to utilize high-temperature energy available from the gasifier to provide part of the energy required to reduce water to hydrogen and oxygen and carbon dioxide to carbon monoxide and oxygen.
Additionally, various embodiments may employ a counter-flow heat exchange device, or other suitable heat transfer device, to transfer heat produced during thermochemical partial oxidation of the carbonaceous fuel to water or carbon dioxide for electrolysis. ... The present invention enables the heat produced during the oxidation of the carbonaceous fuel to be used in the production of syngas. Therefore, a means of producing hydrogen as well as syngas in the absence of an external heat source is provided.
In accordance with one embodiment of the present invention, a method is provided for producing syngas. The method includes thermochemically converting a carbonaceous fuel to produce a heated mixed gas. The heated mixed gas may include water, hydrogen, carbon monoxide and carbon dioxide.
Steam may be produced by transferring heat from the heated mixed gas produced by the thermochemical conversion of the carbonaceous fuel.
Utilizing the heat from the mixed gases produced by the thermochemical conversion process eliminates the need for an external heat source.
The steam may be introduced to at least one solid-oxide electrolysis cell and may be decomposed to produce hydrogen and oxygen. The hydrogen produced by electrolysis of steam may be combined with the heated mixed gas from the gasifier to produce additional syngas. The thermochemical conversion of the carbonaceous fuel may be performed in the presence of a portion of the oxygen produced by electrolysis of steam to control the ratio of carbon dioxide to carbon monoxide in the mixed gas. By augmenting the thermochemical conversion process using oxygen produced by transferring heat from in the mixed gas produced during thermochemical conversion of the carbonaceous fuel, carbon may be used more efficiently.
For example, the method may involve recirculating a sufficient amount of oxygen produced by the at least one solid-oxide electrolysis cell such that the method is substantially carbon-neutral.
In accordance with a further embodiment of the present invention, a process for forming syngas is provided. The method includes thermochemically converting a carbonaceous fuel to produce heat and a mixed gas. The mixed gas may include carbon dioxide, carbon monoxide, hydrogen and water. The heat produced by the thermochemical conversion may be transferred to a water stream to produce steam. The steam may be electrolyzed to produce hydrogen and oxygen. Also a portion of the carbon dioxide recovered from the mixed gas may be co-electrolyzed with water to produce carbon monoxide and hydrogen. The mixed gas may be cooled and water may be removed from the mixed gas to form syngas.
Summary: Various embodiments of the present invention provide methods and systems for forming syngas by combining a thermochemical conversion process of a carbonaceous fuel with an electrolytic process. As used herein, the term "thermochemical conversion process" means and includes combustion, gasification, or pyrolyzation of the carbonaceous fuel. For convenience, the term "thermochemical conversion process," or grammatical equivalents thereof, is used to collectively refer to a combustion process, a gasification process, or a pyrolyzation process, while the terms "combustion," "gasification," or "pyrolyzation," or grammatical equivalents thereof, are used herein to refer to a specific type of thermochemical conversion process. The term "electrolytic process" means and includes a high temperature electrolysis or a co-electrolysis process.
The term "high temperature electrolysis process" is used to refer to the electrolytic decomposition of water into hydrogen and oxygen at a temperature above 500 C, while the term "co-electrolysis process" is used to refer to the simultaneous electrolytic decomposition of water into hydrogen and oxygen and carbon dioxide into carbon monoxide and oxygen.
For convenience, the term "electrolytic process" is used to collectively refer to the terms "high temperature electrolysis process" and "co-electrolysis process."
The term "carbonaceous fuel," as used herein, means and includes (by) way of example only ... a biomass source composed primarily of vegetative matter, such as corn stover, wheat straw, barley straw, tree bark, wood waste, cellulose, bagasse, municipal wastes and combinations thereof.
Additionally, the carbonaceous fuel may include a fossil fuel (and) the fossil fuel may be coal.
The syngas produced from the carbonaceous fuel may be converted to synfuel using a process known in the art such as, for example, a Fischer-Tropsch process.
Hydrogen and/or carbon monoxide produced from high temperature electrolysis of steam or carbon dioxide may be integrated with the thermochemical conversion of a carbonaceous fuel to produce hydrogen or syngas. By utilizing the carbonaceous fuel as a heat source to support the electrolytic process, syngas production may be performed at locations that are remote from an industrial process heat source, such as a nuclear power plant or solar concentrator. Oxygen produced from high temperature electrolysis of steam or carbon dioxide may be used to augment oxygen from an air separation unit or other oxygen enriching process or may replace such devices to produce all of the oxygen required to support production of hydrogen or syngas from a carbonaceous fuel.
The methods and systems described herein may be adapted for use in large-, medium- or small-scale process operations. According to embodiments, syngas may be produced utilizing heat from the combustion of a carbonaceous fuel to support at least one solid-oxide electrolysis cell operably coupled to receive electricity generated from at least one power source. The methods and systems may further include a Fischer-Tropsch process to effectively convert the syngas to a synfuel. By way of non-limiting example, the methods and systems may be varied to produce a syngas with a desired ratio of constituents, more specifically, a molar ratio of hydrogen (H2) to carbon monoxide (CO) of about 2.12:1. If a cobalt catalyst is used to perform the Fischer-Tropsch, the hydrogen to carbon monoxide molar ratio may be in a range of from about 2.0:1 to about 2.12:1. If an iron catalyst is used in the Fischer-Tropsch process, a hydrogen to carbon monoxide molar ratio may be in a range of from about 0.8:1 to about 1.8:1. The molar ratio of hydrogen to carbon monoxide may be varied dependent on the reactor used in the thermochemical conversion apparatus, the process configuration or catalyst used to conduct the Fischer-Tropsch reaction."
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That's really about it:
We the People, through our United States Department of Energy, own, or at least have some "rights to", a technology that can convert our abundant Coal, along with some of our renewable, though sometimes noxious, Carbon-recycling wastes, and some of our agricultural and forestry produce and wastes, into liquid "synfuel", without emitting any Carbon Dioxide to the environment.
Further, if you read the full Disclosure, as accessible via the links, you'll see that supplemental forms of energy are named and specified which could, if wanted, supply additional energy to the process.
But, you will also see that they are, strictly speaking, not needed.
If the percentage of Coal to Biomass and wastes is kept high enough, then the partial oxidation of the Coal in the gasification process can provide all of the thermal energy to, with some conversion into electricity, drive the entire process of gasifying low-energy Biomass and of powering the "solid oxide electrolysis cell"s to reform the water vapor and the byproduct Carbon Dioxide in the raw product synthesis gas into even more Carbon Monoxide and more Hydrogen for addition to the synthesis gas, and for the subsequent "Fischer-Tropsch" synthesis of liquid hydrocarbon fuels.
The supplemental energy would act to help us conserve some of our Coal, but we don't have to have it.
In sum:
Coal can be the basis of the CO2-free, and natural petroleum-free, production of stuff like Gasoline and Diesel, in a process that can also profitably consume stuff like, as specified, "municipal wastes", which we take to mean sewage sludge.
We the People paid to have that technology developed. And, We the People own at least a share of it.
Why haven't We the People been empowered to put our technology for so effectively utilizing our abundant domestic Coal to work, and thereby enabled both to end our crippling economic dependence on OPEC and, by consuming carbonaceous wastes, to improve our physical environment?
Why haven't We the People been deemed worthy enough to even be publicly told about it?