RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application No. 63/405,082, filed September 9, 2022, and entitled “Systems and Methods for Processing Particulate Metallic Transition Metal,” which is incorporated herein by reference in its entirety for all purposes.

TECHNICAL FIELD

Systems and methods for processing particulate metallic transition metal (e.g., iron) are generally described.

SUMMARY

The present disclosure is directed to systems and methods for processing particulate metallic transition metal (e.g., iron). Certain aspects are related to the separation of a gas from particulate metallic transition metal (e.g., iron). Certain aspects are related to the formation of a bulk solid transition metal (e.g., iron) article. The subject matter of the present disclosure involves, in some cases, interrelated products, alternative solutions to a particular problem, and/or a plurality of different uses of one or more systems and/or articles.

Certain aspects are related to methods.

In some embodiments, the method comprises a method of forming a bulk solid iron article. In some embodiments, the method comprises heating and/or pressing particulate metallic iron to form the bulk solid iron article, wherein the bulk solid iron article has a maximum cross-sectional dimension of greater than or equal to 20 millimeters, wherein at least 50 volume percent of the particles of the particulate metallic iron has a maximum cross-sectional dimension of less than or equal to 100 microns.

In some embodiments, the method comprises a method of forming a bulk solid iron article. In some embodiments, the method comprises heating and/or pressing particulate metallic iron to form a briquette having a maximum cross-sectional dimension of greater than or equal to 20 millimeters, wherein at least 80 volume percent of the particles of the particulate metallic iron has a maximum cross-sectional dimension of less than or equal to 100 microns.

In some embodiments, the method comprises separating a gas from particulate metallic iron, wherein at least 50 volume percent of the particles of the particulate metallic iron has a maximum cross-sectional dimension of less than or equal to 100 microns.

In some embodiments, the method comprises separating a gas from particulate metallic iron, wherein at least 80 volume percent of the particles of the particulate metallic iron has a maximum cross-sectional dimension of less than or equal to 100 microns.

Certain aspects are related to systems.

In some embodiments, the system comprises a chamber comprising baffles configured to direct particulate metallic transition metal to the base of the chamber; a first valve upstream of the chamber configured to allow flow of particulate metallic transition metal and a gas into the chamber; a second valve downstream of the first valve, at or above the ceiling of the chamber, and configured to allow flow of the gas out of the chamber; and a third valve downstream of the first valve, at or below the base of the chamber, and configured to allow flow of particulate metallic transition metal out of the chamber.

In some embodiments, the system comprises a chamber; a magnet (e.g., electromagnet) configured to direct the movement of particulate metallic iron to an outlet of the chamber; a first valve upstream of the chamber configured to allow flow of particulate metallic iron and a gas into the chamber; a second valve downstream of the first valve, at or above the ceiling of the chamber, and configured to allow flow of the gas out of the chamber; and a third valve downstream of the first valve, located within the outlet and located at or below the base of the chamber, and configured to allow flow of particulate metallic iron out of the chamber.

Other advantages and novel features of the present disclosure will become apparent from the following detailed description of various non-limiting embodiments of the disclosure when considered in conjunction with the accompanying figures. In cases where the present specification and a document incorporated by reference include conflicting and/or inconsistent disclosure, the present specification shall control. BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting embodiments of the present disclosure will be described by way of example with reference to the accompanying figures, which are schematic and are not intended to be drawn to scale unless otherwise indicated. In the figures, each identical or nearly identical component illustrated is typically represented by a single numeral. For purposes of clarity, not every component is labeled in every figure, nor is every component of each embodiment of the disclosure shown where illustration is not necessary to allow those of ordinary skill in the art to understand the disclosure. In the figures:

FIGS. 1A-1G are cross-sectional schematic illustrations of systems configured to process particulate metallic transition metal (e.g., iron), according to certain embodiments.

FIG. 2 is a flow diagram of an illustrative method of processing particulate metallic iron, according to certain embodiments.

FIG. 3 is a schematic illustration of a system configured to process particulate metallic transition metal (e.g., iron), according to certain embodiments.

FIG. 4 is a schematic illustration of a system suitable for forming a particulate metallic transition metal, separating it from a gas, and forming a bulk solid transition metal article therefrom, according to certain embodiments.

FIG. 5 is a schematic illustration of an exemplary furnace comprising two ports, according to certain embodiments.

FIG. 6 is a schematic illustration of a briquetting subsystem comprising a flat press and rollers.

DETAILED DESCRIPTION

Discussed herein are systems and methods for processing particulate metallic transition metal (e.g., iron). In certain embodiments, a chamber is configured to contain air sensitive and/or pyrophoric material, e.g., particulate metallic transition metal (e.g., direct reduced iron (DRI) powder) under inert conditions after it is reduced in a high temperature furnace, before it is then conveyed to a press (e.g., to be formed into hot briquetted iron (HBI)). Certain embodiments of this chamber are configured to produce HBI, and facilitate the direct transfer of hot (e.g., -500 °C or greater), newly formed DRI as metallic fines (with particle sizes, e.g., under -100 pm) to the briquetting process.

In certain embodiments, methods described herein do not involve an intermediate step that is usually performed before reduction in the traditional production of DRI, namely, a step wherein the iron powder is compressed into small pellets on the order of 1 to 25 mm (e.g., 6 to 25 mm) and held in a batch container before being transferred to a briquetting process. In certain embodiments, by holding the DRI as fines at a high temperature (e.g., at least 200 °C and up to, potentially, 800 °C) in this chamber under an inert atmosphere, while it is newly formed and hot, the powder can be used as a direct input for the briquetting process without the need for reheating. In certain embodiments, methods described herein may thus significantly streamline the HBI production process while increasing the energy efficiency through the mitigation of thermal losses.

In certain embodiments, the MIDREX® process is not applied to produce DRI and post-process it into HBI or some other form. In certain embodiments, because the chamber is configured to process powder rather than pellet form, much higher temperatures (e.g., -700 °C or higher) are not required. Such temperatures are generally required in previous processes in order to have the reducing gas penetrate pellets and form DRI. In some embodiments, to handle fines (also referred to herein as particulate) and avoid hazards that are inherent to handling pyrophoric particulate metallic transition metal (e.g., DRI powder), which can easily aerosolize when disturbed by flowing gas and can explode when exposed to oxygen, an inert gas atmosphere is employed.

In some embodiments, the system comprises a chamber (e.g., a cylindrical chamber, a cuboid chamber, a parallelepiped chamber, or a chamber of another shape), with its central axis aligned vertically, along the direction that gravity acts. Newly formed particulate metallic transition metal (e.g., DRI) may be conveyed from a furnace into the top of the chamber, where it may fall down into the chamber. This bulk incoming particulate metallic transition metal (e.g., DRI powder) may have a particle size below -100 pm at a temperature of approximately 500 °C. In some embodiments, due to the reactivity of the particulate metallic transition metal (e.g., DRI) with any oxidizing environment (e.g., atmospheric oxygen), the particulate metallic transition metal (e.g., DRI) gas within the container is sealed and purged in inert conditions, e.g., argon gas and/or nitrogen gas. In some embodiments, at the bottom of the chamber, the particulate metallic transition metal (e.g., DRI) is transported by a conveyor (e.g., a sloped floor and/or or a magnet (e.g., permanent magnet, electromagnet)) to the briquetting process further downstream, e.g., in a continuous manner. The chamber may, in some embodiments, not be pressurized. In some such embodiments, the inflow of argon and/or nitrogen may be coupled with an exhaust gas outlet.

In accordance with certain embodiments, the integrity of the seals for the chamber are maintained as leak-free as possible, as any leaks of oxygen into this environment with bulk quantities of particulate metallic transition metal (e.g., DRI powder) may result in the rapid production of heat, through oxidation.

In some embodiments, the chamber can sustain a wide range of internal temperatures.

In some embodiments, the chamber operates at a spatially averaged temperature (taken as the spatial average of the temperature within the volume of the container) of at least 200 °C, at least 300 °C, or at least 400 °C. In some embodiments, the chamber operates at a spatially averaged temperature of less than or equal to 800 °C, less than or equal to 700 °C, or less than or equal to 600 °C. Combinations of the above-referenced ranges are also possible (e.g., at least 200 °C and less than or equal to 800 °C, at least 300 °C and less than or equal to 700 °C, at least 400 °C and less than or equal to 600 °C). Other ranges are also possible.

In some embodiments, the chamber operates at a maximum temperature (taken as the maximum temperature within the volume of the container) of at least 200 °C, at least 300 °C, or at least 400 °C. In some embodiments, the chamber operates at a maximum temperature of less than or equal to 800 °C, less than or equal to 700 °C, or less than or equal to 600 °C. Combinations of the above-referenced ranges are also possible (e.g., at least 200 °C and less than or equal to 800 °C, at least 300 °C and less than or equal to 700 °C, at least 400 °C and less than or equal to 600 °C). Other ranges are also possible.

In certain embodiments, to maintain the seals at such high temperatures, localized active cooling elements are implemented around all seals and gaskets to prevent them from melting. This may be achieved through cooling fans on the outer components of the chamber near the seals and internally through embedded heat exchangers that draw heat from the regions around the seals. Conversely, the rest of the chamber body may be insulated to mitigate any thermal losses from the particulate metallic transition metal (e.g., DRI) pile before it is transferred to the briquetting process, which may be carried out at a temperature of, e.g., -650 °C.

In certain embodiments, because the particle size of the particulate metallic transition metal (e.g., DRI) is so fine (e.g., <100 pm), the particulate metallic transition metal (e.g., iron) can become aerosolized and suspended in the flowing gas as it falls into the chamber if mitigating measures are not taken. In some embodiments, to inhibit or prevent the aerosolized powder from being swept into the gas exhaust outlet, active and/or passive measures can be implemented to ensure that the particulate metallic transition metal (e.g., DRI) remain settled at the bottom of the chamber. The internal walls of the chamber may be patterned with baffles, which may redirect the flow of inert gas in a large-scale vortical motion. This cyclonic motion through the chamber may drive the denser particulate metallic transition metal (e.g., DRI) particles toward the walls of the chamber. In addition or as an alternative, a series of magnets (e.g., permanent magnets, electromagnets) may be arranged circumferentially along the walls of the chamber. In some such embodiments, a magnetic field (e.g., a pulsed, large-scale magnetic field) may be applied to pull the particulate metallic transition metal (e.g., DRI) particles toward the chamber walls and down to the bottom of the chamber (e.g., in a pile of metallic transition metal material). Additionally or alternatively, a series of filters and water traps may be installed at the exhaust to capture any remaining particulate metallic transition metal (e.g., DRI) particles that are inadvertently swept up in the exhaust flow.

In certain embodiments, some (e.g., all) mechanical elements of this system comprise (e.g., consist of) stainless steel (e.g., 304, 316, or some comparable alloy). In certain embodiments, valves and other instrumentation comprise (e.g., consist of) stainless steel construction (e.g., 304, 310, 316, or some comparable alloy). The seals, O-rings, and gaskets may comprise (e.g., consist of) high temperature rated silicone, which, in conjunction with various modalities of active cooling, may be able to withstand the high temperature environment of the contained particulate metallic transition metal (e.g., DRI) without melting. The body of the chamber may be insulated with alumina silicate insulating bricks and/or Fiberfrax® insulation.

In certain embodiments, methods described herein do not comprise, prior to briquetting, additional processes implemented to form particulate metallic transition metal (e.g., DRI) pellets, reheat them after they are formed, and convey the pellets to the briquetting step. In certain embodiments, methods and systems described herein streamline this complicated process by directly holding the particulate metallic transition metal (e.g., DRI) powder once it is formed and maintaining it at a high temperature, which may facilitate the briquetting process. Additionally, the use of metallic transition metal (e.g., DRI) fines may more efficiently facilitate the addition of binders or other additives (e.g., bentonite or kaolin) for briquetting.

As noted above, certain aspects are related to methods. The methods may be used to process particulate metallic transition metal (e.g., iron). FIG. 2 is a flow diagram of examples of such methods (e.g., method 600).

In certain embodiments, the method comprises separating a gas from particulate metallic transition metal (e.g., iron). The gas may comprise a reducing gas (e.g., H2), a noble gas (e.g., argon, nitrogen), water vapor, and/or CO2.

In some embodiments, separating the gas from the particulate metallic iron comprises opening a first valve to allow flow of particulate metallic iron and a gas into a chamber. In some embodiments, separating the gas from the particulate metallic iron further comprises opening a second valve downstream of the first valve, at or above the ceiling of the chamber, to allow flow of the gas out of the chamber. In some embodiments, the method further comprises opening a third valve downstream of the first valve, at or below the base of the chamber, to allow flow of particulate metallic iron out of the chamber. In some embodiments, the method comprises closing the first valve and the second valve before opening the third valve.

It is also possible to separate a gas from a particulate metallic transition metal in a manner in which the first valve is left open to allow for continuous flow of the particulate metallic transition metal and the gas into the chamber, the second valve is left open to allow for continuous flow of the gas out of the chamber and/or continuous access to the water trap, and the third valve is opened and closed as needed to feed a system component downstream from the chamber (e.g., a further chamber in which briquetting and/or the formation of a bulk solid metallic article is performed, a further chamber in which one or more steps performed during the foregoing processes are performed, and/or a further chamber in which the particulate metallic transition metal is stored prior to the performance of one or more of the foregoing processes). Continuous flow may comprise flow such that there is no appreciable interruption and/or step change in flow rate during the relevant process. In some embodiments, a relatively high amount of a gas employed in the formation of the particulate metallic transition metal (e.g., a reducing gas) is introduced into the chamber via the first valve. In such instances, it may be desirable for the gas flowing out of the second valve to be redirected back into a vessel in which further particulate metallic transition metal is being formed.

Flow of the particulate metallic iron out of the chamber may comprise flowing the particulate metallic iron into a second chamber comprising inert gas. The inert gas may comprise CO2, N2, noble gas(es) (e.g., argon), and/or any other inert gas. In some embodiments, during the process, less than 1 weight percent (wt%), less than 0.1 wt%, less than 0.01 wt%, less than 0.001 wt%, or less of the inert gas reacts with the particulate transition metal (e.g., particulate metallic iron).

In some embodiments, separating a gas from particulate metallic transition metal (e.g., iron) comprises flowing a combined flow of the gas and the particulate metallic iron adjacent to baffles within a chamber such that the particulate metallic transition metal (e.g., iron) is directed toward the base of a chamber and away from an outlet of the chamber (e.g., the outlet at or above the ceiling of the chamber), and the gas is directed to the outlet.

In some embodiments, the method comprises moving the particulate metallic transition metal (e.g., iron) to a press in an inert (e.g., N2, CO2) atmosphere. Moving the metallic transition metal particles to the inert atmosphere may comprise performing a transfer process in which the metallic transition metal particles are flowed into a container while exposed to the flow of an inert gas.

When a method comprises flowing a combined flow of a gas and a particulate metallic transition metal, the gas flow may have a variety of suitable values. As noted above, the combined flow of the gas and the particulate transition metal may occur during a process in which the particulate transition metal is separated from the gas and/or during a process in which the particulate transition metal is transferred to an inert atmosphere. In some embodiments, the gas flow is less than or equal to 10 L/(min*kg of particulate metallic transition metal), less than or equal to 7.5 L/(min*kg of particulate metallic transition metal), less than or equal to 5 L/(min*kg of particulate metallic transition metal), less than or equal to 2 L/(min*kg of particulate metallic transition metal), less than or equal to 1 L/(min*kg of particulate metallic transition metal), less than or equal to 750 mL/(min*kg of particulate metallic transition metal), less than or equal to 500 mL/(min*kg of particulate metallic transition metal), less than or equal to 200 mL/(min*kg of particulate metallic transition metal), less than or equal to 100 mL/(min*kg of particulate metallic transition metal), less than or equal to 75 mL/(min*kg of particulate metallic transition metal), less than or equal to 50 mL/(min*kg of particulate metallic transition metal), or less than or equal to 20 mL/(min*kg of particulate metallic transition metal). In some embodiments, the gas flow is greater than or equal to 10 mL/(min*kg of particulate metallic transition metal), greater than or equal to 20 mL/(min*kg of particulate metallic transition metal), greater than or equal to 50 mL/(min*kg of particulate metallic transition metal), greater than or equal to 75 mL/(min*kg of particulate metallic transition metal), greater than or equal to 100 mL/(min*kg of particulate metallic transition metal), greater than or equal to 200 mL/(min*kg of particulate metallic transition metal), greater than or equal to 500 mL/(min*kg of particulate metallic transition metal), greater than or equal to 750 mL/(min*kg of particulate metallic transition metal), greater than or equal to 1

L/(min*kg of particulate metallic transition metal), greater than or equal to 2 L/(min*kg of particulate metallic transition metal), greater than or equal to 5 L/(min*kg of particulate metallic transition metal), or greater than or equal to 7.5 L/(min*kg of particulate metallic transition metal). Combinations of the above-referenced ranges are also possible (e.g., less than or equal to 10 L/(min*kg of particulate metallic transition metal) and greater than or equal to 10 mL/(min*kg of particulate metallic transition metal)). Other ranges are also possible.

In embodiments in which two or more gases are flowing, each gas may independently have a gas flow rate in one or more of the above-described ranges and/or all of the gases together may have a flow rate in one or more of the above-described ranges.

In some embodiments, a gas is separated from a particulate metallic transition metal with a relatively high efficiency. For instance, the gas may be separated from the particulate transition metal such that the gas separated from the particulate transition metal makes up less than or equal to 10 wt% of the gases with which the transition metal exits the separation process, less than or equal to 9 wt% of the gases with which the transition metal exits the separation process, less than or equal to 8 wt% of the gases with which the transition metal exits the separation process, less than or equal to 7 wt% of the gases with which the transition metal exits the separation process, less than or equal to 6 wt% of the gases with which the transition metal exits the separation process, less than or equal to 5 wt% of the gases with which the transition metal exits the separation process, less than or equal to 4 wt% of the gases with which the transition metal exits the separation process, or less than or equal to 3 wt% of the gases with which the transition metal exits the separation process. The gas may be separated from the particulate transition metal such that the gas separated from the particulate transition metal makes up greater than or equal to 2 wt% of the gases with which the transition metal exits the separation process, greater than or equal to 3 wt% of the gases with which the transition metal exits the separation process, greater than or equal to 4 wt% of the gases with which the transition metal exits the separation process, greater than or equal to 5 wt% of the gases with which the transition metal exits the separation process, greater than or equal to 6 wt% of the gases with which the transition metal exits the separation process, greater than or equal to 7 wt% of the gases with which the transition metal exits the separation process, greater than or equal to 8 wt% of the gases with which the transition metal exits the separation process, or greater than or equal to 9 wt% of the gases with which the transition metal exits the separation process. Combinations of the above-referenced ranges are also possible (e.g., less than or equal to 10 wt% and greater than or equal to 2 wt%). Other ranges are also possible.

In some embodiments, the flow of a gas and/or a particulate transition metal during a transfer of the particulate transition metal from one vessel to another is continuous.

In certain embodiments, the method comprises a method of forming a bulk solid transition metal (e.g., iron) article. The method may comprise heating and/or pressing (e.g., in a press) particulate metallic transition metal (e.g., iron) to form a briquette.

The temperature to which the particulate metallic transition metal is heated during formation of a bulk solid transition metal article therefrom may be selected as desired. In some embodiments, a particulate metallic transition metal is heated to a temperature of at least 200 °C, at least 300 °C, or at least 400 °C. In some embodiments, a particulate metallic transition metal is heated to a temperature of less than or equal to 800 °C, less than or equal to 700 °C, or less than or equal to 600 °C. Combinations of the above-referenced ranges are also possible (e.g., at least 200 °C and less than or equal to 800 °C, at least 300 °C and less than or equal to 700 °C, at least 400 °C and less than or equal to 600 °C). Other ranges are also possible.

The pressure applied to a particulate metallic transition metal during formation of a bulk solid transition metal article therefrom may be selected as desired. In some embodiments, a pressure of less than or equal to 200 kN/cm, less than or equal to 175 kN/cm, less than or equal to 150 kN/cm, less than or equal to 125 kN/cm, less than or equal to 100 kN/cm, less than or equal to 75 kN/cm, less than or equal to 50 kN/cm, or less than or equal to 25 kN/cm is applied to a particulate metallic transition metal. In some embodiments, a pressure of greater than or equal to 10 kN/cm, greater than or equal to 25 kN/cm, greater than or equal to 50 kN/cm, greater than or equal to 75 kN/cm, greater than or equal to 100 kN/cm, greater than or equal to 125 kN/cm, greater than or equal to 150 kN/cm, or greater than or equal to 175 kN/cm is is applied to a particulate metallic transition metal. Combinations of the above-referenced ranges are also possible (e.g., less than or equal to 200 kN/cm and greater than or equal to 10 kN/cm). Other ranges are also possible.

In some embodiments, a bulk solid transition metal article, such as a briquette, has a relatively large maximum cross-sectional dimension, such as a maximum cross- sectional dimension of greater than or equal to 20 millimeters (and/or, in some embodiments, greater than or equal to 30 millimeters, greater than or equal to 40 millimeters, greater than or equal to 50 millimeters, greater than or equal to 60 millimeters, greater than or equal to 70 millimeters, greater than or equal to 80 millimeters, greater than or equal to 90 millimeters, greater than or equal to 100 millimeters, greater than or equal to 125 millimeters, greater than or equal to 150 millimeters, or greater, and/or less than or equal to 1 meter, less than or equal to 50 centimeters, less than or equal to 250 millimeters, less than or equal to 150 millimeters, less than or equal to 140 millimeters, or less).

In some embodiments, a bulk solid transition metal (e.g., iron) article, such as a briquette, has a root mean square surface roughness that is indicative of its formation from particulate metallic transition metal particles having sizes described herein. In some embodiments, a bulk solid transition metal article has a root mean square surface roughness of greater than or equal to 20 microinches, greater than or equal to 50 microinches, greater than or equal to 75 microinches, greater than or equal to 100 microinches, greater than or equal to 150 microinches, greater than or equal to 200 microinches, greater than or equal to 300 microinches, greater than or equal to 400 microinches, greater than or equal to 500 microinches, greater than or equal to 600 microinches, greater than or equal to 700 microinches, or greater than or equal to 800 microinches. In some embodiments, a bulk solid transition metal article has a root mean square surface roughness of less than or equal to 900 microinches, less than or equal to 800 microinches, less than or equal to 700 microinches, less than or equal to 600 microinches, less than or equal to 500 microinches, less than or equal to 400 microinches, less than or equal to 300 microinches, less than or equal to 200 microinches, less than or equal to 150 microinches, less than or equal to 100 microinches, less than or equal to 75 microinches, or less than or equal to 50 microinches. Combinations of the above-referenced ranges are also possible (e.g., greater than or equal to 20 microinches and less than or equal to 900 microinches, or greater than or equal to 200 microinches and less than or equal to 700 microinches). Other ranges are also possible.

The surface roughness of a bulk solid transition metal article may be measured with the use of a roughness meter.

In some embodiments, at least 50 volume percent (vol%) and/or at least 80 volume percent (vol%) of the particles of the particulate metallic transition metal (e.g., iron) have a maximum cross-sectional dimension that is relatively small. For instance, at least 50 vol% and/or at least 80 vol% of the particles of the particulate metallic transition metal (e.g., iron) have a maximum cross-sectional dimension of less than or equal to 20 micrometers and/or less than or equal to 100 micrometers. Stated another way, in some embodiments, at least 50 vol% and/or at least 80 vol% of the particulate metallic transition metal material is made up of particles having maximum cross-sectional dimensions of less than or equal to 20 micrometers and/or less than or equal to 100 micrometers. In some embodiments, at least 85 vol%, at least 90 vol%, at least 95 vol%, at least 99 vol%, at least 99.9 vol%, at least 99.99 vol%, or up to 100 vol% of the particles of the particulate metallic transition metal (e.g., iron) have a maximum cross- sectional dimension of less than or equal to 20 micrometers and/or less than or equal to 100 micrometers. As used herein, the “maximum cross-sectional dimension” of a particle refers to the largest distance that spans two outer boundaries of the particle. In the case of a perfect sphere, the maximum cross-sectional dimension is the diameter of the sphere.

Without wishing to be bound by any particular theory, it is believed that particles having a maximum cross-sectional dimension of less than or equal to 100 micrometers may be particularly challenging to process (e.g., to form bulk solid transition metal articles, such as briquettes, therefrom). It is believed that such particles, because of their high surface area to volume ratio, may be particularly susceptible to undergoing appreciable oxidation. Such oxidation may make it challenging to retain the metallic nature of the particles and/or may generate sufficient heat to present an undesirably high risk of fire. However, bulk metallic articles formed directly from particles having such small cross-sectional dimension (i.e., without an intermediate step in which the particles are coarsened) may desirably have relatively low surface roughnesses and/or a relatively low amount of contaminants.

In some embodiments, the particulate metallic transition metal (e.g., iron) has a relatively high metallization percentage. For example, in some embodiments, the particulate metallic transition metal (e.g., iron) has a metallization percentage of at least 90%, at least 95%, at least 99%, or at least 99.9%, at least 99.99%, at least 99.999%, or up to 100%. The metallization percentage refers to the mol% of the transition metal material that remains in metallic form (as opposed to a compound form such as an oxide).

FIG. 2 is a flow diagram of an illustrative method 600 of processing particulate metallic iron, according to certain embodiments. In some embodiments, method 600 comprises step 640, separating a gas from particulate metallic transition metal (e.g., iron). In some embodiments, method 600 comprises step 642, moving the particulate metallic transition metal (e.g., iron) into an inert gas environment. In some embodiments, method 600 comprises step 644, heating and/or pressing the particulate metallic transition metal (e.g., iron; e.g., to form a briquette). In some embodiments, method 600 comprises performing step 640, followed by step 642, followed by 644. Some methods may further comprise step 646 of forming a particulate metallic transition metal. When performed, this step may be carried out prior to step 640. In some embodiments, forming a briquette comprises forming a green body from the particulate metallic transition metal and then subjecting the green body to one or more processes to ultimately form the briquette. The green body may be formed by heating and/or pressing the particulate metallic transition metal in an inert atmosphere. In some embodiments, the particulate metallic transition metal may be pressed without heating (e.g., at room temperature).

In some embodiments, pressing a particulate metallic transition metal is performed with the use of a uniaxial press. The pressure applied with the uniaxial press may be greater than or equal to 3.45 MPa, greater than or equal to 5 MPa, greater than or equal to 7.5 MPa, greater than or equal to 10 MPa, greater than or equal to 15 MPa, greater than or equal to 20 MPa, greater than or equal to 25 MPa, or greater than or equal to 30 MPa. The pressure applied with the uniaxial press may be less than or equal to 34.47 MPa, less than or equal to 30 MPa, less than or equal to 25 MPa, less than or equal to 20 MPa, less than or equal to 15 MPa, less than or equal to 10 MPa, less than or equal to 7.5 MPa, or less than or equal to 5 MPa. Combinations of the above-referenced ranges are also possible (e.g., greater than or equal to 3.45 MPa and less than or equal to 34.47 MPa). Other ranges are also possible.

In some embodiments, a green body is formed into a briquette by applying further pressure thereto. This a green body may be pressed without heating (e.g., at room temperature). Pressing a green body may take the form of feeding the green body through rollers that apply pressure thereto. The rollers may apply a pressure of greater than or equal to 10 kN/cm, greater than or equal to 20 kN/cm, greater than or equal to 50 kN/cm, greater than or equal to 75 kN/cm, greater than or equal to 100 kN/cm, greater than or equal to 125 kN/cm, greater than or equal to 150 kN/cm, or greater than or equal to 175 kN/cm. The rollers may apply a pressure of less than or equal to 200 kN/cm, less than or equal to 175 kN/cm, less than or equal to 150 kN/cm, less than or equal to 125 kN/cm, less than or equal to 100 kN/cm, less than or equal to 75 kN/cm, less than or equal to 50 kN/cm, or less than or equal to 20 kN/cm. Combinations of the abovereferenced ranges are also possible (e.g., greater than or equal to 10 kN/cm and less than or equal to 200 kN/cm). Other ranges are also possible.

As noted above, in some embodiments, a method comprises forming a particulate metallic transition metal. The particulate transition metal may be formed from a precursor particulate material comprising the transition metal in a non-elemental form, such as a ceramic comprising cations of the transition metal (e.g., red mud, such as chemically treated red mud; hematite). The precursor particulate material may be subject to a chemical process, such as a reducing process, to form the particulate transition metal and/or to form a particulate material in which a relatively high percentage of the transition metal is in elemental form. This may be accomplished by exposure to a reducing gas, such as hydrogen gas. In some embodiments, a gas separated from a particulate transition metal comprises a gas employed during a process in which the particulate transition metal is formed from a precursor particulate material, such as a reducing gas (e.g., hydrogen).

In some embodiments, a particulate metallic transition metal prepared by the above-described process may have a particle size distribution (e.g., including the vol% of particles having particular maximum cross-sectional dimensions) that are relatively similar to and/or are identical to the particle size distribution of the precursor particulate material.

The steps described in the preceding two paragraphs may be performed in any appropriate vessel, such as furnace and/or a reactor. In some embodiments, it may be desirable to transport a particulate metallic transition metal formed by this process to another type of vessel for one or more further steps, such as one or more of the further steps shown in FIG. 2. This transport may comprise performing step 642 shown in FIG. 2. As one example, in some embodiments, it may be desirable to perform a heating and/or pressing step in an inert gas environment, such as a glove box, and so it may be desirable to move the particulate metallic transition metal into the inert gas environment. Such transfer may be performed by transporting the particulate metallic transition metal from the vessel in which it is formed into a container in the presence of an inert environment and/or in the presence of an environment in which it is exposed to the flow of an inert gas. In some embodiments, such transfer is effected with the use of a feed screw. The container itself may have an inert gas environment and/or may be employed to further transport the particulate metallic transition metal to a different container having an inert gas environment.

As noted above, certain aspects are related to systems. The systems may be used to process particulate metallic transition metal (e.g., iron). FIG. 1A and FIG. 1C are cross-sectional schematic illustrations of examples of such systems (e.g., system 100, system 200).

In certain embodiments, the system comprises a chamber. The chamber may serve to receive a particulate transition metal and serve as a reservoir that holds the particulate transition metal prior to the formation of a bulk solid transition metal article therefrom, such as via a briquetting process. In some embodiments, the chamber received the particulate transition metal after its formation, such as after a reducing process by which it is formed.

In some embodiments, the chamber comprises baffles configured to direct particulate metallic transition metal (e.g., iron) to the base of the chamber. In some embodiments, the baffles are positioned such that they form an angle that is greater than or equal to 30° and/or less than or equal to 65°, relative to the top of the chamber. In some embodiments, the baffles extend down a distance from the top of the chamber that extends at least 30% and/or less than or equal to 75% of the height of the chamber. In some embodiments, the baffles are in the form of plates extending downward from the top of the chamber.

In some embodiments, the system comprises a first valve upstream of the chamber configured to allow flow of particulate metallic transition metal (e.g., iron) and a gas into the chamber. In some embodiments, the system comprises a second valve downstream of the first valve, at or above the ceiling of the chamber, and configured to allow flow of the gas out of the chamber. In some embodiments, the system comprises a third valve downstream of the first valve, at or below the base of the chamber, and configured to allow flow of particulate metallic transition metal (e.g., iron) out of the chamber. In some embodiments, the third valve is located within an outlet of the chamber. The third valve may supply a further vessel, such as a further vessel comprising an inert atmosphere, in which the particulate metallic transition metal is subjected to one or more steps performed during the formation of a bulk solid transition metal article and/or is stored prior to the performance of such step and/or steps. It is also possible for the third valve to supply one or more gases to the chamber in which the particulate metallic transition metal is separated from a gas. For instance, the third valve may supply such a chamber with an inert gas. Supplying an inert gas via the third valve may advantageously assist with separating the gas in the chamber and/or preventing undesirable gases (e.g., reducing gases supplied with the particulate metallic transition metal) from leaving the chamber through the third valve.

It is also possible for a system to comprise one or more further valves. As one example, in some embodiments, a system comprises a fourth valve upstream of the first valve. The fourth valve may serve as a purge valve. When present, such a valve may be employed to introduce an inert gas to the gas and particulate metallic transition metal prior to its flow past the first valve. This may be beneficial in scenarios where, upstream from the first valve, a concentration of one or more non-inert gases (e.g., one or more reducing gases) is undesirably high. For instance, in some instances, a particulate metallic transition metal is flowing upstream of the first valve in the presence of a relatively high amount of a reducing gas, such as an amount that would make the separation of the particulate metallic transition metal therefrom challenging to perform or that would introduce an undesirably high concentration of the reducing gas into a chamber downstream from the first valve. In such embodiments, it may be desirable to dilute the reducing gas with an inert gas upstream from the first valve.

In some embodiments, the transition metal comprises iron. In certain embodiments, the transition metal is iron.

In certain embodiments, the system comprises a filter downstream of the second valve and configured to capture residual particulate metallic transition metal and allow flow of the gas through the filter. In certain embodiments, the system comprises a water trap downstream of the second valve. In such instances, it may be desirable for the second valve to be maintained in an open position during separation of a gas from a particulate metallic transition metal to allow for the water trap to be in fluidic communication with the chamber in which such separation occurs.

Water traps may be configured to capture residual particulate metallic transition metal and/or allow flow of the gas through the water trap and out through an outlet. In certain embodiments, the system further comprises a filter downstream of the second valve and upstream of the water trap, wherein the filter is configured to capture residual particulate metallic transition metal and allow flow of the gas through the filter.

In certain embodiments, the system comprises a magnet (e.g., electromagnet, permanent magnet) configured to direct the movement of a particulate metallic transition metal to an outlet of the chamber within which the third valve is located, wherein the transition metal is iron. In some embodiments, the magnet (e.g., electromagnet) is positioned outside of the chamber. In some embodiments, the magnet (e.g., electromagnet) is positioned below the base of the chamber.

In certain embodiments, the system comprises a plurality of magnets (e.g., electromagnets) configured to direct the movement of a particulate metallic transition metal to the outlet of the chamber within which the third valve is located, wherein at least one of the magnets (e.g., electromagnets) is positioned along the side of the chamber and/or at least one of the magnets (e.g., electromagnets) is positioned below the base of the chamber. In some embodiments, the plurality of magnets (e.g., electromagnets) is positioned outside of the chamber. In some embodiments, some of the magnets (e.g., electromagnets) are positioned circumferentially along the sides of the chamber.

In certain embodiments, the system comprises a sloped floor at the base of the chamber, configured to direct the movement of the particulate metallic transition metal to the third valve.

In some embodiments, a chamber has a relatively advantageous ratio of length or width to height. The height of the chamber is the spatial extent of the interior of the chamber along the direction of gravity. The length and width of the chamber are the spatial extents of the interior of the principal axes of the chamber in the direction perpendicular to gravity. In some embodiments, the principal axis along which the length is measured is parallel to the direction along which particulate metallic transition metal flows through the chamber and/or has a smaller angle with respect to the direction along which particulate metallic transition metal flows through the chamber than the other principal axis perpendicular to gravity. A chamber may have a ratio of length or width to height of greater than or equal to 1.2:1, greater than or equal to 1.5:1, greater than or equal to 1.75:1, greater than or equal to 2:1, greater than or equal to 3:1, greater than or equal to 5 : 1 , or greater than or equal to 7.5 : 1. A chamber may have a ratio of length or width to height of less than or equal to 10:1, less than or equal to 7.5:1, less than or equal to 5:1, less than or equal to 3:1, less than or equal to 2:1, less than or equal to 1.75:1, or less than or equal to 1.5:1. Combinations of the above-referenced ranges are also possible (e.g., greater than or equal to 1.2:1 and less than or equal to 10:1). Other ranges are also possible. FIGS. 1A-1G are cross-sectional schematic illustrations of systems configured to process particulate metallic transition metal (e.g., iron), according to certain embodiments.

FIG. 1A depicts an illustrative system 100 comprising: a chamber 132 comprising baffles 134 configured to direct particulate metallic transition metal to the base of chamber 132; a first valve 106 upstream of chamber 132 configured to allow flow of particulate metallic transition metal and a gas into chamber 132; a second valve 118 downstream of first valve 106, at or above the ceiling of chamber 132, and configured to allow flow of the gas out of chamber 132; and a third valve 114 downstream of first valve 106, at or below the base of chamber 132, and configured to allow flow of particulate metallic transition metal out of chamber 132. Walls 116 of chamber 132 may comprise a thermally insulating material.

FIG. IB depicts illustrative system 100 comprising: a chamber 132 comprising baffles 134 configured to direct particulate metallic transition metal 108 to the base of chamber 132; a first valve 106 upstream of chamber 132 configured to allow flow 102 of particulate metallic transition metal and a gas into chamber 132; a second valve 118 downstream of first valve 106, at or above the ceiling of chamber 132, and configured to allow flow 128 of the gas out of chamber 132; and a third valve 114 downstream of first valve 106, at or below the base of chamber 132, and configured to allow flow 112 of particulate metallic transition metal 108 out of chamber 132. Walls 116 of chamber 132 may comprise a thermally insulating material.

FIG. 1C depicts an illustrative system 200 comprising: a chamber 232; a magnet (e.g., electromagnet) 238 configured to direct the movement of particulate metallic iron to an outlet 246 of chamber 232; a first valve 206 upstream of chamber 232 configured to allow flow of particulate metallic iron and a gas into chamber 232; a second valve 218 downstream of first valve 206, at or above the ceiling of chamber 232, and configured to allow flow of the gas out of chamber 232; and a third valve 214 downstream of first valve 206, located within outlet 246 and located at or below the base of chamber 232, and configured to allow flow of particulate metallic iron out of chamber 232. Walls 216 of chamber 232 may comprise a thermally insulating material.

FIG. ID depicts illustrative system 200 comprising: a chamber 232; a magnet (e.g., electromagnet) 238 configured to direct the movement of particulate metallic iron 208 to an outlet 246 of chamber 232; a first valve 206 upstream of chamber 232 configured to allow flow 202 of particulate metallic iron and a gas into chamber 232; a second valve 218 downstream of first valve 206, at or above the ceiling of chamber 232, and configured to allow flow 228 of the gas out of chamber 232; and a third valve 214 downstream of first valve 206, located within outlet 246 and located at or below the base of chamber 232, and configured to allow flow 212 of particulate metallic iron 208 out of chamber 232. Walls 216 of chamber 232 may comprise a thermally insulating material.

FIG. IE depicts illustrative system 300 comprising: a chamber 332 comprising baffles 334 configured to direct particulate metallic transition metal 308 to the base of chamber 332; a first valve 306 upstream of chamber 332 configured to allow flow 302 of particulate metallic transition metal and a gas into chamber 332; a second valve 318 downstream of first valve 306, at or above the ceiling of chamber 332, and configured to allow flow 328 of the gas out of chamber 332; and a third valve 314 downstream of first valve 306, at or below the base of chamber 332, and configured to allow flow 312 of particulate metallic transition metal 308 out of chamber 332. Chamber 332 further comprises a sloped floor 310 at the base of chamber 332, configured to direct the movement of particulate metallic transition metal 308 to third valve 314. System 300 further comprises a water trap 322 downstream of second valve 318 and configured to capture residual particulate metallic transition metal 308 and allow flow 326 of the gas through water trap 322 and out through an outlet 324. Walls 316 of chamber 332 may comprise a thermally insulating material.

FIG. IF depicts illustrative system 400 comprising: a chamber 432 comprising baffles 434 configured to direct particulate metallic transition metal 408 to the base of chamber 432; a first valve 406 upstream of chamber 432 configured to allow flow 402 of particulate metallic transition metal and a gas into chamber 432; a second valve 418 downstream of first valve 406, at or above the ceiling of chamber 432, and configured to allow flow 428 of the gas out of chamber 432; and a third valve 414 downstream of first valve 406, at or below the base of chamber 432, and configured to allow flow 412 of particulate metallic transition metal 408 out of chamber 432. Chamber 432 further comprises a sloped floor 410 at the base of chamber 432, configured to direct the movement of particulate metallic transition metal 408 to third valve 414. System 400 further comprises a water trap 422 downstream of second valve 418 and configured to capture residual particulate metallic transition metal 408 and allow flow 426 of the gas through water trap 422 and out through an outlet 424. System 400 further comprises a filter 436 downstream of second valve 418 and upstream of water trap 422, wherein filter 436 is configured to capture residual particulate metallic transition metal 408 and allow flow 448 of the gas through filter 436. System 400 further comprises a plurality of magnets (e.g., electromagnets) 438 configured to direct the movement of a particulate metallic transition metal 408 to an outlet 446 of chamber 432 within which third valve 414 is located, wherein some of the magnets (e.g., electromagnets) 438 are positioned along the side of chamber 432 (e.g., wherein some of the magnets (e.g., electromagnets) 438 are positioned circumferentially along the sides of chamber 432) and some of the magnets (e.g., electromagnets) 438 are positioned below the base of chamber 432. Walls 416 of chamber 432 may comprise a thermally insulating material.

FIG. 1G depicts illustrative system 500 comprising: a chamber 532 comprising magnets (e.g., electromagnets) 538 positioned below the base of chamber 532 and configured to direct particulate metallic transition metal 508 to outlet 546 of chamber 532; a first valve 506 upstream of chamber 532 configured to allow flow 502 of particulate metallic transition metal and a gas into chamber 532; a second valve 518 downstream of first valve 506, at or above the ceiling of chamber 532, and configured to allow flow 528 of the gas out of chamber 532; and a third valve 514 downstream of first valve 506, at or below the base of chamber 532, and configured to allow flow 512 of particulate metallic transition metal 508 out of chamber 532. System 500 further comprises a water trap 522 downstream of second valve 518 and configured to capture residual particulate metallic transition metal 508 and allow flow 526 of the gas through water trap 522 and out through an outlet 524. Walls 516 of chamber 532 may comprise a thermally insulating material.

FIG. 3 shows a further schematic example of a system suitable for separating a gas from a particulate metallic transition metal. The system shown in FIG. 3 may be suitable for feeding a system in which the particulate metallic transition metal is formed into a bulk solid iron article, such as a briquette.

FIG. 4 shows a schematic example of a system suitable for forming a particulate metallic transition metal, separating it from a gas, and forming a bulk solid transition metal article therefrom. Systems described herein may comprise some or all of the components shown in FIG. 4, and/or may comprise further components. It is also possible for multiple systems to be employed together, each of which has some or all of the components shown in FIG. 4. FIG. 4 depicts system 700 comprising particulate metallic transition metal formation subsystem 750, gas separation subsystem 752, and briquetting subsystem 754. As shown in FIG. 4, such subsystems may be connected to each other by conduits 756 and 758 (which connect the particulate metallic transition metal formation subsystem 750 to gas separation subsystem 752, and gas separation subsystem 752 to briquetting subsystem 754, respectively). As noted above, such conduits may take the form of feed-screws, although other designs are also possible. It is also possible for such conduits to be absent. In such embodiments, material may be transported from one subsystem to another by an operator (e.g., via a container).

Particulate metallic transition metal formation subsystem 750 shown in FIG. 4 may be suitable for forming a particulate metallic transition metal, such as from a precursor particulate material. In some instances, it may comprise a furnace. In such embodiments, the furnace may have one or more ports through which one or more gases, such as a reducing gas for reducing a precursor particulate material and/or an inert gas, may be introduced. An exemplary furnace 860 comprising two ports 862 and 864 is shown in FIG. 5.

Gas separation subsystem 752 shown in FIG. 4 may be suitable for separating a particulate metallic transition metal from a gas, such as a gas employed in transition metal formation subsystem 750. It may have a design shown for any of systems 100-500 of FIGS. 1A-1G and/or may include one or more features shown in such systems.

Briquetting subsystem 754 shown in FIG. 4 may be suitable for forming bulk solid transition metal articles, such as briquettes, from particulate metallic transition metals. The particulate metallic transition metals may be supplied by gas separation subsystem 752. Briquetting subsystems may comprise one or more heating and/or pressing components (e.g., one or more heated flat presses, one or more pairs of heated rollers) that may be employed to heat and/or press particulate metallic transition metals. FIG. 6 shows briquetting subsystem 954 comprising flat press 966 and rollers 968.

The transition metal can comprise, in some embodiments, scandium (Sc), yttrium (Y), lanthanum (La), actinium (Ac), titanium (Ti), zirconium (Zr), hafnium (Hf), rutherfordium (Rf), vanadium (V), niobium (Nb), tantalum (Ta), dubnium (Db), chromium (Cr), molybdenum (Mo), tungsten (W), seaborgium (Sg), manganese (Mn), technetium (Tc), rhenium (Re), bohrium (Bh), iron (Fe), ruthenium (Ru), osmium (Os), hassium (Hs), cobalt (Co), rhodium (Rh), iridium (Ir), meitnerium (Mt), nickel (Ni), palladium (Pd), platinum (Pt), darmstadtium (Ds), copper (Cu), silver (Ag), gold (Au), roentgenium (Rg), zinc (Zn), cadmium (Cd), mercury (Hg), and/or copernicium (Cn). In some embodiments, the transition metal originates from mining tailings.

In some embodiments, particles of a particulate metallic transition metal may further comprise one or more materials in addition to the particulate transition metal. As one example, the particles of a particulate transition metal may further comprise a binder, such as bentonite clay.

The following examples are intended to illustrate certain embodiments of the present invention, but do not exemplify the full scope of the invention.

EXAMPLE 1

50 grams of fine magnetite (particle size less than 200 microns) were added to a vessel that was sealed off and heated with hydrogen. The resulting product was directly reduced iron (DRI). The DRI was then scooped under argon into a holding chamber attached to the reactor vessel. The holding chamber included magnets on the base and a connecting tube to prevent fines from pluming. The holding chamber was purged with additional argon prior to being sealed with a ball valve. The DRI from the holding chamber was then transferred into another inert chamber where the DRI was then pressed into a pellet.

EXAMPLE 2

This Example demonstrates the formation of bulk solid iron articles from particulate metallic iron.

First, particulate metallic iron was prepared. Chemically treated red mud having for which 50 vol% of the particles had a maximum cross-sectional dimension of less than 20 microns was placed in a sealed furnace and then heated in the presence of excess hydrogen gas for 4 hours. This reduced the red mud particles to form the particulate metallic iron. Then, the particulate metallic iron was transferred from the furnace to a glove box. This was accomplished by first employing a feed screw to cause the particulate metallic iron to fall into a chamber under a slow argon gas bleed. After the particulate metallic iron transfer, the chamber was sealed and then placed in the glove box.

Finally, the particulate metallic iron underwent a briquetting process to form bulk solid iron articles. The particulate metallic iron was removed from the chamber and loosely pressed into blocks inside the glove box. After removal from the glove box, these blocks exhibited limited reactivity with air, with oxidation mostly limited to their exterior surfaces.

While several embodiments of the present invention have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the functions and/or obtaining the results and/or one or more of the advantages described herein, and each of such variations and/or modifications is deemed to be within the scope of the present invention. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the teachings of the present invention is/are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, the invention may be practiced otherwise than as specifically described and claimed. The present invention is directed to each individual feature, system, article, material, and/or method described herein. In addition, any combination of two or more such features, systems, articles, materials, and/or methods, if such features, systems, articles, materials, and/or methods are not mutually inconsistent, is included within the scope of the present invention.

The indefinite articles “a” and “an,” as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean “at least one.” The phrase “and/or,” as used herein in the specification and in the claims, should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Other elements may optionally be present other than the elements specifically identified by the “and/or” clause, whether related or unrelated to those elements specifically identified unless clearly indicated to the contrary. Thus, as a non-limiting example, a reference to “A and/or B,” when used in conjunction with open-ended language such as “comprising” can refer, in one embodiment, to A without B (optionally including elements other than B); in another embodiment, to B without A (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc.

As used herein in the specification and in the claims, “or” should be understood to have the same meaning as “and/or” as defined above. For example, when separating items in a list, “or” or “and/or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as “only one of’ or “exactly one of,” or, when used in the claims, “consisting of,” will refer to the inclusion of exactly one element of a number or list of elements. In general, the term “or” as used herein shall only be interpreted as indicating exclusive alternatives (i.e. “one or the other but not both”) when preceded by terms of exclusivity, such as “either,” “one of,” “only one of,” or “exactly one of.” “Consisting essentially of,” when used in the claims, shall have its ordinary meaning as used in the field of patent law.

As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, “at least one of A and B” (or, equivalently, “at least one of A or B,” or, equivalently “at least one of A and/or B”) can refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc.

Some embodiments may be embodied as a method, of which various examples have been described. The acts performed as part of the methods may be ordered in any suitable way. Accordingly, embodiments may be constructed in which acts are performed in an order different than illustrated, which may include different (e.g., more or less) acts than those that are described, and/or that may involve performing some acts simultaneously, even though the acts are shown as being performed sequentially in the embodiments specifically described above.

Use of ordinal terms such as “first,” “second,” “third,” etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish the claim elements.

In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of’ and “consisting essentially of’ shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures, Section 2111.03.