Patent Application
20080314730
The present invention relates to methods and apparatuses for using microwave radiation. More particularly, the present invention relates to methods and apparatuses for decomposing compositions comprising petroleum-based materials.
Petroleum-based materials are integral to the world's economy and demand for such fuels and consumer products is increasing. As the demand rises, there is a need to efficiently and economically extract petroleum-based materials to fulfill that demand. As such, it would be advantageous to not only be able to extract petroleum-based materials from the earth, but to also recycle consumer products to recapture those petroleum-based materials.
Worldwide oil consumption is estimated at seventy-three million barrels per day and growing. Thus, there is a need for sufficient oil supplies. Tar sands, oil sands, oil shales, oil cuttings, and slurry oil contain large quantities of oil, however, extraction of oil from these materials is costly and time-consuming and generally does not yield sufficient quantities of usable oil.
Soil contaminated with petroleum products is an environmental hazard, yet decontamination of petroleum-tainted soil is time-consuming and expensive.
Furthermore, it has been estimated that 280 million gallons of oil-based products such as plastics go into landfills each day in the United States. It would be desirable to recapture and recycle the raw materials of these products.
Scrap vehicle tires are a significant problem worldwide and their disposal presents significant environmental and safety hazards, including fires, overflowing landfills, and atmospheric pollution. While there are a number of existing applications for these tires, including tire-derived fuels, road construction, and rubber products, these applications are insufficient to dispose of all the available scrap tires. The major components of tires are steel, carbon black, and hydrocarbon gases and oils, which are commercially desirable. As such, it is advantageous to develop processes for the recovery of these products from scrap vehicles tires. Prior art methods of decomposing scrap vehicle tires do not produce commercial-grade carbon black and require high temperatures and extended exposure times for recovery of the hydrocarbon components. Efficient removal of hydrocarbons from materials such as drilling fluids and sludge or sewage would also be beneficial in that it would simply the disposal or recycling of such materials.
Efforts to recycle tires using microwave technology has been described in U.S. Pat. Nos. 5,507,927 and 5,877,395 to Emery. Efforts to recover petroleum from petroleum-impregnated media has been described in U.S. Pat. Nos. 4,817,711 and 4,912,971 to Jeambey. Efforts to decompose plastics using microwave radiation has been described in U.S. Pat. No. 5,084,140 to Holland. The prior work has involved the use of single-frequency microwave radiation. Single-frequency microwave radiation can be a slow process that does not provide uniform heating. Moreover, single-frequency microwave radiation typically results in arcing on metal components.
Thus, there is a need for methods and apparatuses for the recycling of petroleum-based compositions and for the recovery of petroleum-based materials from composites containing petroleum-based materials. The invention is directed to these and other important needs.
In meeting the described challenges, one aspect of the present invention provides a method for chemically altering a carbon-containing composition, comprising: altering the chemical structure of at least a portion of the composition by applying microwave radiation comprising at least one frequency component in the range of from about 7.5 GHz to about 8.5 GHz to the composition; so as to give rise to at least one carbon-containing molecule being released from the composition.
Also provided is a method for removing a carbon-containing fluid from a carbon-containing composition, comprising: subjecting the composition to microwave radiation for a time sufficient to release the carbon-containing fluid, the microwave radiation comprising at least one frequency component in the range of from about 7.5 GHz to about 8.5 GHz.
Additionally provided is an apparatus for recovering a carbon-containing fluid from a liquid, viscous, gel, or solid carbon-containing composition, comprising: a microwave radiation generator capable of supplying microwave radiation characterized as having at least one frequency component in the range of from about 7.5 GHz to about 8.5 GHz; and at least one container or conduit capable of collecting or transporting said carbon-containing fluid from said composition.
Further provided is an apparatus for obtaining a carbon-containing fluid from a liquid, solid, gel, or viscous carbon-containing composition, comprising: a microwave radiation generator capable of supplying microwave radiation characterized as having at least one frequency component in the range of from about 7.5 GHz to about 8.5 GHz; and at least one container to collect the carbon-containing fluid.
The general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as defined in the appended claims. Other aspects of the present invention will be apparent to those skilled in the art in view of the detailed description of the invention as provided herein.
The summary, as well as the following detailed description, is further understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings exemplary embodiments of the invention; however, the invention is not limited to the specific methods, compositions, and devices disclosed. In addition, the drawings are not necessarily drawn to scale. In the drawings:
The present invention may be understood more readily by reference to the following detailed description taken in connection with the accompanying figures and examples, which form a part of this disclosure. It is to be understood that this invention is not limited to the specific devices, methods, applications, conditions or parameters described and/or shown herein, and that the terminology used herein is for the purpose of describing particular embodiments by way of example only and is not intended to be limiting of the claimed invention. Also, as used in the specification including the appended claims, the singular forms “a,” “an,” and “the” include the plural, and reference to a particular numerical value includes at least that particular value, unless the context clearly dictates otherwise. The term “plurality”, as used herein, means more than one. When a range of values is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms another embodiment. All ranges are inclusive and combinable.
It is to be appreciated that certain features of the invention which are, for clarity, described herein in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any subcombination. Further, reference to values stated in ranges include each and every value within that range.
“Sweeping,” as the term is used herein, is defined as the application of a plurality of radiation frequencies over a period of time.
“Pulsing,” as used herein, means subjecting the composition to microwave radiation for a period of time, followed by periods of time wherein the composition is not subjected to microwave radiation.
“Oil,” as used herein, means any hydrocarbon or petroleum-based oil.
“Gas,” as used herein, includes any hydrocarbon-based material that is in the gaseous state at atmospheric temperature and pressure and includes, but is not limited to, methane, ethane, propane, butane, isobutene, or mixtures thereof.
“Carbon black,” as used herein, includes any grade of commercially-acceptable carbon black, including, but not limited to, rubber black.
“Oil sands,” also known as “tar sands,” are deposits of bitumen, a heavy black viscous oil.
“Oil shale” is sedimentary rock containing a high proportion of Kerogen, which, when heated, can be converted into oil.
“Slurry oil” is refinery waste oil.
“Oil cuttings” are the waste product generated during the drilling of oil wells. Examples of oil cuttings include, but are not limited to, bits and pieces of oil-soaked soil and rock.
“Hydrocarbons” are compositions that comprise carbon and hydrogen.
“Carbon-based” refers to matter that comprises carbon.
“Decompose,” “decomposing,” and “chemically altering” refer to a process whereby matter is broken down to smaller constituents. For example, solids can be broken down into particles, liquids, vapors, gases, or any combination thereof; rubbery materials can be broken down into liquids, vapors, gases, or any combination thereof; viscous liquids can be broken down to lower viscosity liquids, vapors, gases, or any combination thereof; liquids can be broken down to vapors, gases, or any combination thereof; composite materials comprising inorganic solids and trapped organic matter can be broken down to inorganic solids and released organic vapors and gases, and the like. In some cases decompose, decomposing and chemically altering also include changes in molecular structure.
1 Torr=1 mm Hg=1 millimeter mercury.
“Altering the chemical structure” refers to breaking one or more bonds within a given molecule, forming one or more bonds within a given molecule, forming one or more radicals from a given molecule, or any combination thereof.
“Releasing” refers to making the molecule, fluid, or structure available for transportation, collection, volatilization, condensation, and the like.
In one aspect, the present invention provides methods for chemically altering a carbon-containing composition. These methods include altering the chemical structure of at least a portion of the composition by applying microwave radiation comprising at least one frequency component in the range of from about 7.5 GHz to about 8.5 GHz to the composition so as to give rise to at least one carbon-containing molecule being released from the composition.
The energy value of the carbon-containing molecule released from the composition can be at least about 20% greater than the energy of the microwave radiation applied to the composition, at least about 50% greater than the energy of the microwave radiation applied to the composition, at least about 100% greater than the energy of the microwave radiation applied to the composition, at least about 500% greater than the energy of the microwave radiation applied to the composition, or even at least about 700% or about 900% greater than the energy of the microwave radiation applied to the composition. Sample data are shown in Tables 8.
The microwave radiation suitably includes one or more discrete frequency components. Such components are preferably in the range of from about 7.9 to about 8.3 GHz.
The microwave radiation can also include a range of microwave radiation frequency components. The microwave radiation frequency may vary within the range of frequencies, and may be swept within a range of about +/−0.50 GHz of a single microwave radiation frequency component. In some embodiments, the range of microwave radiation frequency components can include a bandwidth of about 4 GHz. The range of frequency components of said radiation can be in the C-Band frequency range or in the X-Band frequency range. Suitable microwave radiation may also include at least one additional frequency component in the range of from 4.0 GHz to about 12 GHz.
The environment proximate to said composition suitably includes less than about 12 molar % molecular oxygen or less than 12 weight % molecular oxygen, or less than about 8 molar % molecular oxygen, or less than about 8 weight % molecular oxygen. The present inventive method may be performed at a pressure of less than about one atmosphere; without being bound to any particular theory of operation, it is believed that operating at sub-atmospheric pressure facilitates recovery of hydrocarbons from a carbon-containing composition.
Altering includes hydrocarbon cracking, radical formation, cleaving of one or more carbon-carbon bonds, hydrocarbon volatilization, or any combination thereof. Altering includes reducing hydrocarbon molecules having more than about 44 carbons to hydrocarbon molecules having fewer than about 30 carbons, to hydrocarbon molecules having fewer than about 20 carbons, to hydrocarbon molecules having fewer than about 10 carbons, to methane, or to molecular hydrogen.
Altering also includes reducing hydrocarbon molecules having more than about 100 carbons to hydrocarbon molecules having fewer than about 50 carbons, to hydrocarbon molecules having fewer than about 20 carbons, to hydrocarbon molecules having fewer than about 20 carbons, to methane, or to molecular hydrogen.
Altering also includes reducing hydrocarbon molecules having more than about 1000 carbons to hydrocarbon molecules having fewer than about 50 carbons, to hydrocarbon molecules having fewer than about 20 carbons, to hydrocarbon molecules having fewer than about 20 carbons, to methane, or to molecular hydrogen. Polyolefins such as polyethylene and polypropylene are examples of hydrocarbon molecules having more than 1000 carbon atoms.
Altering additionally includes reducing hydrocarbon molecules having more than about 100,000 carbons to hydrocarbon molecules having fewer than about 50 carbons, to hydrocarbon molecules having fewer than about 20 carbons, to methane, or to molecular hydrogen.
The methods also include exposing the carbon-containing composition to an inert gas atmosphere. Suitable inert gases include argon, helium, and other noble gases.
According to the methods, the ambient pressure surrounding the composition is suitably less than atmospheric pressure, or less than about 40 Torr, or less than about 20 Torr, or even less than about 5 Torr.
During the course of the irradiation, the temperature of said composition suitably does not exceed about 1200° C. Depending on process variables and sample materials, the temperature of said composition suitably does not exceed about 700° C., or exceed about 400° C., or exceed about 300° C., or exceed about 150° C.
Suitable carbon-containing compositions include, inter alia, material derived from a tire, such as tire pieces. Such compositions are decomposed to form at least one of oil, gas, steel, sulfur, and carbon black. Gas, oil, fuel, hydrogen, and hydrocarbons formed by decomposing tire material according to the claimed method are also included within the present invention.
Other suitable carbon-containing compositions include at least one plastic. Suitable plastics include, but are not limited to, ethylene (co)polymer, propylene (co)polymer, styrene (co)polymer, butadiene (co)polymer, polyvinyl chloride, polyvinyl acetate, polycarbonate, polyethylene terephthalate, (meth)acrylic (co)polymer, acetal (co)polymer, ester(co)polymer, amide (co)polymer, etherimide (co)polymer, lactic acid (co)polymer, or any combination thereof. Plastics are suitably decomposed by the method to give rise to at least one monomer. Gas, oil, fuel, hydrogen, monomers, and hydrocarbons formed by decomposing plastics according to the claimed method are also included within the present invention.
Additional suitable carbon-containing compositions include tar sand, oil sand, scrap automotive parts, oil cuttings, oil shale, drilling fluid, dredge, sewage, sludge, plant matter, biomass, bunker oil, solvent, comingled recyclables, separated recyclables, or any combination thereof. Gas, oil, fuel, hydrogen, methane, or any combination thereof produced by decomposing suitable carbon-containing compositions according to the claimed method are within the scope of the present invention.
The applying of the microwave radiation may occur in the presence of a catalyst. Suitable catalysts include carbonaceous material, such as wood char. CaO is also considered a suitable catalysts.
The method also includes the step of collecting the carbon-containing molecules liberated from the composition.
The present invention also provides methods for removing a carbon-containing fluid from a carbon-containing composition. Such methods include subjecting the composition to microwave radiation for a time sufficient to release the carbon-containing fluid, the microwave radiation comprising at least one frequency component in the range of from about 7.5 GHz to about 8.5 GHz. The microwave radiation suitably includes at least one frequency component in the range of from about 7.9 GHz to about 8.3 GHz.
The energy value of the carbon-containing molecule released from the composition can be at least about 20% greater than the energy of the microwave radiation applied to the composition, at least about 50% greater than the energy of the microwave radiation applied to the composition, at least about 100% greater than the energy of the microwave radiation applied to the composition, at least about 500% greater than the energy of the microwave radiation applied to the composition, or even at least about 700% or about 900% greater than the energy of the microwave radiation applied to the composition.
The radiation can also suitably include one or more discrete frequency components, in the range of from about 7.9 to about 8.3 GHz. Suitable microwave radiation also includes a range of microwave radiation frequency components; the microwave radiation can be varied within the range of frequency components and can even be swept within a range of about +/−50 MHz of a single microwave radiation frequency component. A suitable range of microwave radiation frequency components includes a bandwidth of about 4 GHz. Suitable ranges also include C-Band frequency range and X-Band frequency range microwave radiation, as well as the frequency range of from about 7.9 GHz to about 8.3 GHz. Microwave radiation suitably includes microwave radiation having at least one frequency component in the range of from about 4 GHz to about 12 GHz.
Ambient environments suitable for the claimed methods include environments including less than about 12 molar % molecular oxygen, or less than about 8 molar % molecular oxygen, or less than about 12 weight % molecular oxygen, or less than about 8 weight % molecular oxygen.
The methods suitably include recovering released carbon-containing fluid; such fluids include vapors, liquids, and supercritical fluids. Recovery is suitably performed at a pressure of less than one atmosphere.
The methods also include subjecting the carbon-containing composition to microwave radiation so a to break at least one carbon-carbon bond of the composition.
The methods include altering the carbon-containing composition by hydrocarbon cracking, radical formation, cleaving of one or more carbon-carbon bonds, hydrocarbon volatilization, or by any combination thereof.
Altering can include reducing hydrocarbon molecules having more than about 44 carbons to hydrocarbon molecules having fewer than about 30 carbons, or to hydrocarbon molecules having fewer than about 20 carbons, or to hydrocarbon molecules having fewer than about 10 carbons, or to methane, or even to molecular hydrogen.
The altering also includes reducing hydrocarbon molecules having more than about 100 carbons to hydrocarbon molecules having fewer than about 50 carbons, to hydrocarbon molecules having fewer than about 20 carbons, to hydrocarbon molecules having fewer than about 20 carbons, to methane, or to molecular hydrogen. Altering also includes reducing hydrocarbon molecules having more than about 1000 carbons to hydrocarbon molecules having fewer than about 50 carbons, to hydrocarbon molecules having fewer than about 20 carbons, to hydrocarbon molecules having fewer than about 20 carbons, to methane, or to molecular hydrogen. Altering additionally includes reducing hydrocarbon molecules having more than about 100,000 carbons to hydrocarbon molecules having fewer than about 50 carbons, to hydrocarbon molecules having fewer than about 20 carbons, to methane, or to molecular hydrogen.
The methods include exposing the carbon-containing composition to an inert gas atmosphere; suitable inert gases are described elsewhere herein.
The ambient pressure surrounding the composition is suitably less than atmospheric pressure, or less than about 40 Torr, or less than about 20 Torr, or less than about 5 Torr.
During the course of the irradiation, the temperature of said composition suitably does not exceed about 1200° C. Depending on certain variables, the temperature of said composition suitably does not exceed about 700° C., about 400° C., about 300° C., or about 150° C.
The methods suitably include subjecting the composition to the microwave radiation so as to vaporize at least a portion of the carbon-containing fluid. The method also suitably includes collecting the carbon-containing fluid in at least one collection vessel.
Suitable carbon-containing compositions include tar sands, oil sands, oil shale, slurry oil, oil cuttings, automotive scrap, recycled materials, vegetable matter, dredge, sludge, bunker oil, or any combination thereof. The method further includes transporting the carbon-containing fluid at a pressure less than one atmosphere to at least one container to collect the carbon-containing fluid. Where the carbon-containing fluid is a petroleum-based product, the method includes the collecting and transporting of that product at a pressure less than one atmosphere and refining the petroleum-based product.
The method suitably includes carbon-containing compositions where the carbon-containing composition includes less than 1 percent by weight hydrocarbons based on weight composition after the carbon-containing fluid has been released. The methods also includes fuels, monomers, oils, gases, hydrocarbons, methane, and molecular hydrogen produced according to the methods.
Application of the microwave radiation can occur in the presence of a catalyst. Suitable catalysts are described elsewhere herein.
Also disclosed are apparatuses for recovering a carbon-containing fluid from a liquid, viscous, gel, or solid carbon-containing composition. Such apparatuses suitably include a microwave radiation generator capable of supplying microwave radiation characterized as having at least one frequency component in the range of from about 7.5 GHz to about 8.5 GHz; and at least one container or conduit capable of collecting or transporting said carbon-containing fluid from said composition.
The generator is suitably capable of applying microwave radiation characterized as having at least one frequency component in the range of from about 7.9 GHz to about 8.3 GHz. The generator is also suitably capable of supplying microwave radiation comprising at least one frequency component in the range of from about 7.9 to about 8.3 GHz. Suitable generators include klystrons, traveling wave tubes, variable frequency magnetrons, magnetrons, or any combination thereof. Suitable generators are further capable of supplying microwave radiation characterized as having at least one frequency component in the range of from about 7.5 to about 8.3 GHz.
Suitable generators are further capable of varying the components of the supplied microwave radiation frequency. Frequency components include radiation in the C-Band frequency range, radiation in the X-Band frequency range, radiation in the range of from about 7.7 GHz to about 8.3 GHz, and radiation in the range of from about 7.9 GHz to about 8.3 GHz.
The apparatuses also suitably include at least one chamber for holding said composition. Suitable chambers are closed to the outside atmosphere, and are capable of operating at an internal pressure of less than 40 Torr, at an internal pressure of less than about 20 Torr, or even at an internal pressure of less than about 5 Torr.
Further disclosed are apparatuses for obtaining a carbon-containing fluid from a liquid, solid, gel, or viscous carbon-containing composition; such apparatuses include a microwave radiation generator capable of supplying microwave radiation characterized as having at least one frequency component in the range of from about 7.5 GHz to about 8.5 GHz; and at least one container to collect the carbon-containing fluid.
Suitable microwave generators are described elsewhere herein. Where the microwave generator includes a klystron, the klystron is suitably capable of supplying microwave radiation having a frequency component in the range of from about 7.9 GHz to about 8.3 GHz.
The generator is capable of supplying microwave radiation characterized as having at least one frequency component in the range of from about 7.9 GHz to about 8.3 GHz. The generator is also capable of supplying a microwave radiation characterized as having at least one frequency component in the range of from about 8.0 and about 8.2 GHz. The range of frequency components of said radiation is suitably in the C-Band frequency range, or in the X-Band frequency range.
A suitable apparatus further includes at least one chamber for holding the carbon-containing composition. The chamber is suitably closed to the outside atmosphere, and is suitably capable of operating at an internal pressure of less than about 40 Torr, or at an internal pressure of less than about 20 Torr, or at an internal pressure of less than about 5 Torr.
The apparatus also suitably includes a temperature detector for monitoring the carbon-containing composition or the environment internal to the apparatus. Suitable temperature detectors include infrared instruments, shielded thermocouples, and the like.
An exemplary embodiment of the present invention is depicted in
The microwave reactor room 116 is also depicted having refrigeration equipment 123 for maintaining constant room temperature. Processed tire chips exit the microwave reactor 154 (
As shown in
Microwaves are generally generated outside of the microwave room and transported into the microwave room by a suitable microwave conduit, e.g. stainless steel wire. The design and interconnection of the three microwave reactors in series is provided so that the location of the tire chips in the microwave radiation zone is maintained so that the tire chips do not exceed 465° F. Initially, “popping” of the tire begins in the first reactor 150 when the temperature of the tire chips is in the range of from about 300° F. to about 450° F. It has been surprisingly found that once the temperature exceeds about 450° F., the carbon black residing within the tires can be charred and overcooked and the efficiency of the process for recovering hydrocarbon fuel oils diminishes drastically. Accordingly temperature is desirably maintained below about 465° F., or even below about 550° F. Without being bound by any particular theory of operation, it appears that the tire chips pop because the reactors are under vacuum and a lot of gas within the tire chips is being released suddenly upon irradiation with microwaves.
Suitable operating pressures are the range of up to about 20 mm of mercury, or even up to about 40 mm of mercury, or even up to about 100 mm of mercury. Accordingly, tire chips processed in the first microwave reactor 150 are then transported to the second microwave reactor 152, where the processed chips are further irradiated under vacuum using microwave antennas 162. The tire chips are further reduced in size, and fall through mesh 174, and then transported to the third microwave reactor 154. In the third microwave reactor 154, the processed chips are further irradiated using microwave antenna 164. Processed chips are finally transported by a screw feed discharge section 118 and exit the microwave reactors from screw feed discharge section 166, and through airlock (not shown) and onto conveyor 156.
Each of the microwave reactors are fed with microwave conduits terminating in a suitable cone or nozzle. The first microwave reactor has more microwave nozzles 160 as it is larger than the other two microwave reactors. The second microwave reactor is shown with microwave nozzles 162, and the third microwave reactor is shown with microwave nozzles 164. Each of the microwave reactors contains vacuum lines 180 to transport the resulting hydrocarbon gases to the high-capacity heat exchanger 118 (shown in dotted lines). Also shown in the microwave room 124 are refrigeration equipment 123 to maintain the temperature of the ambient conditions in the microwave room, and support structures 158 for supporting the microwave reactors.
Suitable microwave ranges for the processing of tire chips includes using X-band microwave radiation generators (not shown) transmitted via conduit in tubes at various frequencies to each of the reactors. Microwave frequencies for tire processing varies from X-band down towards C-Band radiation. X-band is 5.2 to 10.9 GHz; C-band is 3.9 to 6.2 GHz. K-band radiation is also useful in some embodiments. K-band is 10.9 GHz to 35 GHz, which includes the sub-bands Ku (15.35 GHz to 17.25 GHz) and Ka (33.0 GHz to 36.0 GHz). Typically separate microwave antenna tubes are separated in frequency by approximately 0.2 gigahertz. In the embodiment shown in
The plant layout described in
The system described in
The system described in
Suitable microwave radiation frequency ranges from about 8.0 to about 8.8 GHz, or in the range of from about 8.1 GHz to about 8.7 GHz, or even in the range of from about 8.2 GHz to about 8.6 GHz, or even in the range of from about 8.3 GHz to about 8.5 GHz, or even about 8.4 GHz. The microwave reactor contains a series of microwave cone antennas that radiate the atomized residual oil with microwaves. These microwave cone antennas can each receive the same or different microwave frequencies. When the frequencies differ, they typically are separated by increments of about 0.2 GHz. Ranges of microwave frequencies are typically useful for processing the atomized residual oil in this manner. Accordingly multiple microwave antennas 344 receive microwaves generated by a plurality of microwave generators 342 provided in the microwave control system 340. Microwaves are transmitted through microwave antennas 344 to the microwave antenna conduit 336. Microwaves then enters the microwave reactor. Typically the residual oil 362 is pre-heated to a temperature of about 350° C. so that it is capable of flowing under pressure and atomized. The use of microwaves has been demonstrated to effectively crack the hydrocarbon chains in the heavy residual oil. Atomization helps to increase the surface area of the residual oil and decrease particle size, thereby effectuating absorption of the microwaves and cracking of the hydrocarbon chains. The residual oil is suitably heated to temperatures sufficient that can flow under pressure and atomized. Suitable temperatures are at least about 250° C., or even at least about 300° C., or even at least about 350° C., or even at least about 400° C., or even at least about 450° C., or even at least about 500° C. The residual oil may be preheated using any of a variety of heating methods, for example convection, conduction, or irradiation, e.g. microwaves. The heavy residual oil chains crack at least several times.
Processes according to the present invention are capable of producing combustible gases. The processes according to the present invention are also capable of producing at least several different weights of oils. These oil products range from carbon content of hydrocarbon chains comprising from 14 carbons up to about 25 carbons. The starting residual oils comprise hydrocarbon chains having at least 25 carbons or even at least 28 carbons. The hydrocarbons in the residual oil do not necessarily need to be linear hydrocarbon chains, for example cyclic and branched hydrocarbons are also envisioned. Instead of atomization, hot flowing residual oil can be formed into a thin film and irradiated with microwaves, or can be ejected into a shooting stream and irradiated with microwaves, or can be broken into droplets under force of pressure and irradiated with microwaves. Similar related processes give rise to narrow dimension residual oil droplets. In certain embodiments the products of microwave radiation within the microwave reactor 330 illustrated in
Using the methods of the present invention, the petroleum-based materials can be vaporized and collected at surface-level and processed using techniques known in the art.
Various hydrocarbon geological deposits can be processed underground using this technology at various depths. Piping for the wells can start at a diameter of about 24 inches at the surface, which diameter is progressively narrower and narrower as sections of piping are added as the depth increases. At a depth of approximately 3000 feet, a typical opening (diameter) of the piping is about 6 inches. For example oil shale deposits in the Western part of the United States are relatively shallow, i.e., near the surface. Strip mines are also relatively shallow, and other deposits may be as deep as 2000 feet or more. Previously pumped oil wells often have chambers of oil that are not readily accessible but require opening by an additional explosive or drilling operation. Certain chambers can also be opened by irradiating the sealing rock material with microwaves. In a laboratory setting, it has been discovered that oil shale pops and reduces in size when irradiated with microwaves. As the oil shale releases hydrocarbons (i.e. oil), the oil shale “pops” like popcorn. Accordingly, directionalizing microwaves within the geological chambers can give rise to breakdown of the geological formation (i.e. the rocks pop, break apart, and fall down and fill the cavity). Accordingly, the antennas can be moved around within geological formations to aid in recovering hydrocarbon material. In some embodiments microwave antennas are placed down about 5000 feet or more, and then are directionalized to travel on the order of approximately 100 yards or so horizontally.
Any type of hydrocarbon material present within the geological formation can be cracked to gas and recovered at the surface using fractionalization condensation units. For example, any carbon suitable for use as diesel fuel can be made by irradiating oil shale. Resulting diesel fuel is suitably used as Cat Diesel Engine Oil. Sometimes oil wells are drilled using directional drilling technologies. Suitable directional drilling technologies are capable of bending at a rate of a degree a foot to create an angle. Accordingly, flexible microwave antennas are suitable for use in such oils. Accordingly, the process includes uncapping a capped oil well. This can be accomplished by drilling out a concrete plug used to cap the well, if present.
The system can include a number of auxiliary equipment located on the surface of the ground. Such equipment includes, for example, well drilling equipment, vacuum pump vehicle, fuel tank vehicles, a generator vehicle, and microwave control vehicle that includes microwave generators, microwave waveguides, and associated equipment. The vacuum pump vehicle can contain a vacuum pump that is capable of applying intermittent vacuum pulse technology to raise hydrocarbon gases to the surface. The hydrocarbon gases are recovered and collected in a suitable distillation tower or fractionation tower that is fitted with heat exchanger and condensing unit. Suitable oil wells and other hydrocarbon geological deposits residing in the ground are accessed via a tube to provide a sealed system with the vacuum pump vehicle for producing the vacuum environment needed for recovering a hydrocarbon vapors. Suitable vacuums include absolute pressures of less than about 20 mm of mercury, or even less than about 40 mm of mercury, or even less than about 100 mm of mercury. The microwave control vehicle contains suitable flexible microwave waveguides and generators. Typically the end of the microwave waveguides (e.g., antennas) are fitted with a suitable microwave cone emitter (e.g., nozzle). The antennas are placed into the mahogany zone in Earth in situ and microwaves are used to radiate tar sands, or oil shale, or other hydrocarbon deposits. The microwaves cause vaporization and gasification of the otherwise viscous and solid-like hydrocarbon and carbon geological sources within the ground. One or more antenna fitted with one or more cone emitter devices can be used.
Generated hydrocarbon gases (e.g., take off gases) are transported to a suitable fractionation tower capable of separating the gas, as illustrated in
Another embodiment of an apparatus of the present invention is depicted in
As an example, a suitable microwave rotating reactor drum system for extracting hydrocarbons from materials such as drill cuttings and fluids can comprise the following equipment:
A suitable microwave control center includes a number of hydrocarbon specific modular microwave generators, high power amplifiers, master controller module, slave driven power modules, thermal sensors, safety I/O devices for vacuum, interlocks, and emergency shut down, manifold banked configuration of flexible waveguides/windows/adapter plates, thermal metrology gear microwave power measurement instruments and computer control station as per schedule.
A suitable 4′-0″ diameter rotating in-feed channel drum unit with vacuum seal provisions comprises ⅜″ stainless steel welded frame construction and bolt on stainless steel (replaceable) hardened steel troughs driven by a direct coupled, 5-hp NEMA-4 variable speed (VFD driven) indexing servo-motor to transfer metered product into the feed screw.
A suitable 2′-6″ diameter×12′-6″ long in-feed screw assembly comprises heavy-duty stainless steel 2″ square tubing frame supporting ⅜″ stainless steel skins with hardened helical screw driven by a direct coupled, 2-hp NEMA-4 variable speed (VFD) servo-motor to transfer metered product into the reactor vessel.
A suitable 5′-0″ diameter×⅜″ horizontal seamlessly welded stainless steel and jacketed sub-baric vessel is constructed with internal angular flight bars, (length varies depending on composition of the intended process to) with two—24″ long×⅜″ stainless steel end cap sections, hardened steel circum-centerline rack & pinion hydraulic transmission driven by a variable speed gear-head motor. Includes a maintenance access door, piping as required to heat vessel jacket, microwave antenna mountings, vacuum port, pressure/flow meters and gauges as required, power transmission is stainless steel guarded. Reactor tank and peripheral equipment is supported by heavy duty stainless steel formed structural channels and heavy duty external bearing wheels.
A suitable 2′-6″ diameter×12′-6″ long discharge screw assembly comprises heavy-duty stainless steel 2″ square tubing frame supporting ⅜″ stainless steel skins with hardened helical screw driven by a direct coupled, 2-hp NEMA-4 variable speed (VFD) servo-motor to transfer metered product into the reactor vessel.
A suitable NEMA 4 electrical motor control panel, 480v/3ph/60 Hz-24 volt control circuits controls all motors and devices, directly mounted to shipping container wall, includes Allen-Bradley PLC, touch screen diagnostics, VFD drive components, I/O racks, rigid conduit with all marine wire specs, color coded, tagged and match-marked for easy identification.
A suitable vacuum system comprises Dual to Quad (which varies according to throughput) 1.5-hp oil-lubricated, rotary vane vacuum pumps system for −20 in. Hg. continuous duty operation. A vacuum release port system is mounted on the discharge screw section.
Electron activator. It has been discovered that microwave radiation in the frequency range of from about 4 GHz to about 12 GHz is useful for selectively recovering hydrocarbon materials from geological petroleum and mineral sources, as well as manufactured materials such as automobile and truck tires. It has further been found that such materials can comprise carbon particles that absorb energy when irradiated with microwave radiation. The heat from the energized carbon particles is released to the adjacent hydrocarbon materials, and when sufficient heat is released, the hydrocarbons are reduced in molecular weight, i.e., “cracked”, and vaporized. A particular range of frequencies has been found to be efficacious for the electromagnetic stimulation and heating of carbon particles for recovering hydrocarbons, such as diesel fuel, from difficult to recover hydrocarbon sources.
Disclosed are methods for microwave treatment of difficult-to-recover hydrocarbon source materials comprising contacting the hydrocarbon source material with particles comprising carbon, and subjecting the hydrocarbon source material to microwave radiation. Also disclosed are methods for microwave treatment of hydrocarbon source material comprising contacting the hydrocarbon source material with material having a resonating frequency in the range of from about 4 GHz to about 12 GHz, and subjecting the hydrocarbon source material to microwave radiation characterized as having at least one frequency component that corresponds to the resonating frequency of the material. As used herein, carbon particles or material having a resonating frequency corresponding to the applied microwave radiation frequency are collectively referred to as “electron activator”.
In preferred embodiments of the disclosed methods, the microwave radiation is one or more pre-selected microwave radiation frequencies. Preferably, the pre-selected microwave radiation frequency will be the resonating microwave frequency, i.e., the microwave radiation frequency at which the particles comprising carbon absorb a maximum amount of microwave radiation. It has been determined that different compositions of the present invention will absorb more or less microwave radiation, depending on the frequency of the microwave radiation applied. It has also been determined that the frequency at which maximum microwave radiation is absorbed differs by composition. By using methods known in the art, a composition of the present invention can be subjected to different frequencies of microwave radiation and the relative amounts of microwave radiation absorbed can be determined. Preferably, the microwave radiation selected is the frequency that comparatively results in the greatest amount of microwave radiation absorption. In one embodiment, the pre-selected microwave radiation frequency is characterized as having at least one frequency component in the range of from about 4 GHz to about 12 GHz. In other embodiments, the pre-selected microwave radiation frequency is characterized as having at least one frequency component in the range of from about 5 GHz to about 9 GHz, from about 6 GHz to about 8 GHz, or from about 6.5 GHz to about 7.5 GHz.
The particles comprising carbon are preferably carbon substances that have a resonating microwave frequency of from about 4 GHz to about 12 GHz. Many forms of carbon are known by those skilled in the art, and, while not intending to exclude other carbon types, it is contemplated that any form of carbon having a resonating microwave frequency of from about 4 GHz to about 12 GHz will be within the scope of the present invention. For example, the particles comprising carbon can comprise carbon black. Carbon black may be described as a mixture of incompletely-burned hydrocarbons, produced by the partial combustion of natural gas or fossil fuels.
Carbon blacks have chemisorbed oxygen complexes (e.g., carboxylic, quinonic, lactonic, phenolic groups and others) on their surfaces to varying degrees depending on the conditions of manufacture. These surface oxygen groups are collectively referred to as the volatile content. In preferred embodiments, the present invention uses carbon black having a moderate volatile content. The volatile content of the preferred carbon black can be composed of hydrocarbons having up to about 20 carbon atoms, or even up to about 30 carbon atoms.
The constituent parts of the electron activator preferably have characteristic dimensions in the micrometer range, although other particle or fragment sizes may also be used. Because carbon particles or particles comprising another electron activator for use in the present invention can be present in numerous configurations, and can be irregular in shape, the term “characteristic dimensions” is used herein to describe the long axis in the case of substantially cylindrical or otherwise oblong particles, and to describe diameter in the case of substantially spherical particles, etc. In some embodiments wherein the carbon particles comprise carbon black, the particles can have characteristic dimensions of about 10 nm to about 250 μm. In other embodiments, the particles can have characteristic dimensions of about 100 nm to about 100 μm, or of about 200 nm to about 10 μm.
Preferred are electron activators having characteristic dimensions that are conducive to ready dispersion within hydrocarbon materials that are targeted for vaporization. The electron activators can be contacted with the hydrocarbon materials by directly introducing the electron activators into the hydrocarbon materials environment.
In the present systems, the electron activator particles can comprise any material that is capable of absorbing at least a portion of the transmitted microwave radiation generated by the microwave generator. In preferred embodiments the material comprises carbon. The particles comprising carbon are preferably carbon substances that have a resonating microwave frequency of from about 4 GHz to about 12 GHz. Many forms of carbon are known by those skilled in the art, and, while not intending to exclude other carbon types, it is contemplated that any form of carbon having a resonating microwave frequency of from about 4 GHz to about 12 GHz will be within the scope of the present invention. For example, the particles comprising carbon can comprise carbon black. Carbon blacks have chemisorbed oxygen complexes (e.g., carboxylic, quinonic, lactonic, phenolic groups and others) on their surfaces to varying degrees depending on the conditions of manufacture. These surface oxygen groups are collectively referred to as the volatile content. In preferred embodiments, the present invention uses carbon black having a moderate volatile content prepared by processing tire chips using microwave radiation as described herein above.
The constituent parts of the particles preferably have characteristic dimensions in the micrometer range, although other particle or fragment sizes may also be used. Because carbon particles or particles comprising another electron activator for use in the present invention can be present in numerous configurations, and can be irregular in shape, the term “characteristic dimensions” is used herein to describe the long axis in the case of substantially cylindrical or otherwise oblong particles, and to describe diameter in the case of substantially spherical particles, etc. In some embodiments wherein the carbon particles comprise carbon black, the particles can have characteristic dimensions of about 100 μm.
The following examples are provided to further describe the present invention. They are not to be construed to limit the scope of the invention described in the claims. Many of the examples make use of the apparatus substantially illustrated and described in
A chamber capable of being subjected to between 4.0 to 12.0 GHz of microwave radiation frequencies and rated to withstand reduced atmospheric pressure, was equipped with a 700 W, 5.8 to 7.0 GHz VFM microwave tube (Lambda Technologies, Morrisville, N.C.). The chamber was outfitted with a nitrogen gas inlet tube, a vacuum inlet tube, and an outlet tube connected to a heat exchanger and collection vessel. The chamber was also equipped with an infrared thermocouple temperature probe.
A chamber capable of being subjected to between 4.0 to 12.0 GHz of microwave radiation frequencies and rated to withstand reduced atmospheric pressure, was equipped with a 1800 W, 7.3 to 8.7 GHz VFM microwave tube (Lambda Technologies, Morrisville, NC). The chamber was outfitted with an nitrogen gas inlet tube, a vacuum inlet tube, and an outlet tube connected to a heat exchanger and collection vessel. The chamber was also equipped with an infrared thermocouple temperature probe.
A 20 lb automobile tire was cut into approximately 4″×4″ pieces. These pieces were washed and dried. The pieces were placed on a tray and loaded into the chamber of Example 1. Twenty psi of N2 was introduced into the chamber. The VFM microwave radiation was initiated (700 W, 5.8-7.0 GHz). When the temperature of the tire pieces reached 465° F., the microwave radiation was halted and the tire pieces allowed to cool about 5-25° F. Microwave radiation was resumed. This process was repeated an additional three times. Total experiment run time was approximately twelve minutes. The decomposition products were then analyzed.
This experiment produced 1.2 gallons of #4 oil (see Tables 1 and 2), 7.5 lbs of carbon black, 50 cu. ft. of combustible gases (including methane, ethane, propane, butane, and isobutene), and 2 lbs of steel.
A sample of oil cuttings, oil shale, tar sands, oil sands, slurry oil, and/or a material contaminated with petroleum-based materials, is placed in the apparatus of Example 2. The pressure is reduced to 20 Torr. Microwave radiation is applied to the sample for a time sufficient to vaporize all the petroleum-based material in the sample. At 20 Torr, the petroleum-based materials vaporize between about 400 and 520° F. The vaporized petroleum-based materials are cooled and collected in a collection vessel. The material remaining in the chamber is substantially free of petroleum-based material.
A plastic bottle was placed in the apparatus of Example 1 and exposed to microwave radiation. The exposure to microwave radiation resulted in complete vaporization of the bottle and recovery of petroleum-based materials.
When ranges are used herein for physical properties, such as molecular weight, or chemical properties, such as chemical formulae, all combinations, and subcombinations of ranges for specific embodiments therein are intended to be included.
The disclosures of each patent, patent application, and publication cited or described in this document are hereby incorporated herein by reference, in its entirety.
In another example, residual oil was exposed to microwave radiation from a 1.6 kW traveling wave tube of 8300 MHz, at a setting of about 80% of the traveling wave tube's power. The irradiation was performed at a pressure of −20 psi for 13 minutes. The composition reached a maximum temperature of 310° C. Before exposure to the radiation, the sample weighed about 100 grams; after exposure, the sample weighed about 4.6 grams.
Material liberated from the sample by the radiation was then analyzed on a mass spectrometer, the results of which analysis are illustrated in
From the residual oil, relatively heavy hydrocarbons having chain lengths in the C24 to C44 range were the most commonly recovered hydrocarbons from the residual oil.
In another example, a previously-used, commercially-available drilling fluid was exposed to a traveling wave tube applying sweeping band microwave radiation between 7.9 GHz and 8.3 GHz at a power setting of about 76% of the available 1.6 kW power of the traveling wave tube. The sample was irradiated at a pressure of −550 mm Hg for 9 minutes. The composition reached a maximum temperature of about 212° C. Before exposure to the radiation, the sample weighed about 100 grams; after exposure, the sample weighed about 98.1 grams.
The hydrocarbons liberated by the irradiation were then analyzed on a mass spectrometer, the results of which analysis are shown in
The temperature of the drilling fluid sample as a function of time during the irradiation is illustrated in
In another example, commercially-available, generic tires were exposed to 8300 MHz microwave radiation from a 1.6 kW traveling wave tube at about 64% of the traveling wave tube's maximum power. The irradiation was performed at a pressure of −550 mm Hg for 9 minutes. The tire composition reached a maximum temperature of about 170° C. Before exposure to the radiation, the tire sample weighed about 100 grams; after exposure, the sample weighed about 98.1 grams.
The hydrocarbons liberated by the irradiation were then analyzed on a mass spectrometer, the results of which analysis are shown in
The temperature of the composition as a function of time is illustrated in
In another example, bituminous coal was exposed to microwave radiation sweeping between 7.9 GHz and 8.3 GHz, and generated by a 1.6 kW traveling wave tube operating at 84% of maximum power. The irradiation was performed at a pressure of −550 mm Hg for 3 minutes. The composition reached a maximum temperature of about 201° C. Before exposure to the radiation, the sample weighed about 66.1 grams; after exposure, the sample weighed about 48.2 grams.
The hydrocarbons liberated by the irradiation were then analyzed on a mass spectrometer, the results of which analysis are shown in
The temperature of the bituminous coal sample as a function of time during irradiation is illustrated in
In another example, so-called automotive fluff comprising shredded automotive parts, was exposed to microwave radiation sweeping between 7.9 GHz and 8.3 GHz, and generated by a 1.6 kW traveling wave tube operating at 84% of maximum power. The irradiation was performed at a pressure of about −550 mm Hg for about 10 minutes. The composition reached a maximum temperature of about 337° C.
Before exposure to the radiation, the sample weighed about 100 grams; after exposure, the sample weighed about 43 grams. The hydrocarbons liberated by the irradiation were then analyzed on a mass spectrometer, the results of which analysis are shown in
In another example, commercially-produced oil cuttings were exposed to microwave radiation sweeping between 7.9 GHz and 8.3 GHz, and generated by a 1.6 kW traveling wave tube operating at 84% of maximum power. The irradiation was performed at a pressure of −550 mm Hg for 2 minutes. The composition reached a maximum temperature of about 63° C. Before exposure to the radiation, the sample weighed about 200 grams; after exposure, the sample weighed about 175 grams.
The hydrocarbons liberated by the irradiation were then analyzed on a mass spectrometer, the results of which analysis are shown in
The temperature of the irradiated oil cuttings as a function of time is shown in
A summary of the results from applying radiation of various frequencies to various sample materials is shown in Table 7.
As seen in Table 7, a radiation frequency of 7.9 GHz yielded the best recovery, on a weight basis, of hydrocarbons from all samples. Frequencies below and above 7.9 GHz did not result in optimum recovery. This result stands in contrast to the data of European Patent Application EP0601798 (filed Dec. 2, 1993, by Murphy), in which microwave frequencies centered around 0.915 GHz, 2.45 GHz, 5.80 GHz, and 22.0 GHz were deemed particularly preferable.
Table 8 summarizes the energy balances for certain of the sample materials listed in Table 7, and sets forth the amount of energy applied to each sample, the amount of energy present in the compositions extracted and recovered from each irradiated sample, and the net energy gain for each samples irradiated at a given wavelength. As shown, the energy content of the hydrocarbon material recovered from the various samples was higher than the energy required to extract the hydrocarbon material from the samples, and the net energy balance was most favorable when the applied radiation frequency was 7.9 GHz for all samples.
The energy balances for the sample materials listed in Table 8 are plotted in
Those skilled in the art will appreciate that numerous changes and modifications can be made to the preferred embodiments of the invention and that such changes and modifications can be made without departing from the spirit of the invention. It is, therefore, intended that the appended claims cover all such equivalent variations as fall within the true spirit and scope of the invention.
This patent application claims the benefit of U.S. Patent Application No. 60/943,991, filed on Jun. 14, 2007, the entirety of which is incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| 60943991 | Jun 2007 | US |
