Systems and methods for modifying steelmaking slag

Abstract

The present disclosure includes a method of treating steelmaking slag that can include the steps of transferring slag from a source furnace to a slag furnace and mixing the slag with one or more additives while the slag is in a molten state to produce a modified slag. In some aspects, slag is transferred to a slag pot to separate the slag from residual steel within the slag. The residual steel may be recycled back into the steelmaking process and the remaining slag can be processed to form the modified slag which can be utilized to produce a target product.

Description

FIELD OF INVENTION

[0001] The present invention relates generally to processing steelmaking slag, and more specifically, to systems and methods for modifying slag to produce a commercially viable material.BACKGROUND

[0002] Currently, the production of liquid steel includes a primary steel making process and a secondary steelmaking process. The primary steel making process involves producing a molten steel where the secondary steelmaking process involves refining of the steel. The primary steel making process takes place in a process furnace such as converter, electric arc furnace (EAF) or induction furnace, and the secondary steelmaking processes takes place in a secondary furnace, such as a ladle refining furnace or vacuum degassing furnace. Both the primary and the secondary steelmaking processes involve the presence of slag, where the physical and chemical properties of the slag can change the quality of the produced steel.

[0003] FIG. 1 depicts an example of a continuous casting steelmaking process where steel scrap 10 is provided to an electric arc furnace (EAF) 14 that produces molten steel 18 and an electric arc furnace slag 22 byproduct. The molten steel 18 from the EAF is transferred to a ladle furnace 26 that produces refined steel 30 and a ladle furnace (LF) slag 34. The refined steel 30 is then transferred to a continuous casting machine 38 for the casting of the liquid steel. After casting the liquid steel other steps and process (e.g., rolling mill, etc.) can be utilized to produce the finished steel 42.

[0004] Conventionally, the EAF slag (EAFS) and LF slag (LFS) were mixed together and discarded. However, recent processes separate the EAF slag from the LF slag as the EAF slag can be further processed to be recycled or reused. As depicted in FIG. 1, EAF slag 22 can be sent to a cooling yard 46 where the slag is cooled (e.g., via water spraying) and then a processing unit 50 for further processing. The processing unit 50 can crush the solidified, cooled EAF slag and remove any remaining metallic fraction, leaving a remaining by-product called electric arc furnace (EAF) aggregate 54.

[0005] Currently, LF slag offers very limited usage and application and is conventionally sent to a landfill 58. The LF slag 34 includes a high content of free calcium oxide (CaO) and magnesium oxide (MgO) that is detrimental to the quality of the EAF aggregate 54 and, therefore, is kept separated from EAF slag 22. Some processes have been proposed to attempt to recover any residual steel within LF slag 34, but these have been found unsuitable as these processes cause additional environmental disturbances, such as dust emission and additional economical cost that does not offset the value of any recovered steel. Consequently, cooled, and de-metalized LF slag is usually landfilled which is costly and an environmental liability.SUMMARY

[0006] Some of the present systems, methods, and apparatuses described herein provide an economical option for treating steelmaking slag, such as LF slag, EAF slag, stainless steel slag, argon oxygen decarburization (AOD) slag, or the like, to recover residual steel, produce a useable product, or both. One aspect of the present systems utilizes a dedicated slag furnace to homogenously mix materials with the steelmaking slag (e.g., LF slag) to produce a modified slag that can be used as a material to produce other products. As one example, where the steelmaking slag is LF slag, which expands and disintegrates due to its mineralogy when cool, the slag furnace can efficiently make use of the sensible heat of the LF slag during processing to decrease energy usage and maintain the slag in a molten phase to reduce expansion and disintegration.

[0007] The slag furnace also includes features, as described herein, to provide homogeneous mixing of the LF slag that is not possible when additives are added directly to the ladle during the process cycle or to a slag pot during transfer of the slag to the slag pot. With the operations and systems described herein, a modified LF slag can be consistently produced with good characteristics that result from the homogenous mixing, among other things. The present systems and operations provide an economically viable and environmentally sustainable way to treat steel making slag.

[0008] Some aspects of the described features include a method of treating slag, such as ladle furnace slag, EAF slag, stainless steel slag, argon oxygen decarburization slag, or other slags. The method can include transferring slag from a container, such as a ladle or slag pot, to a slag furnace and mixing the slag with one or more additives in the slag furnace. In some configurations, the slag is in a molten state within the slag furnace. Some methods can include pre-heating the one or more additives within the slag furnace prior to transferring the slag to the slag furnace. The methods can include separating, the slag into a residual steel component and a slag component that is substantially free of steel. In some of the described configurations, the transferring the slag includes transferring slag from the ladle to a slag pot and transferring slag from the slag pot to the slag furnace. In other configurations, transferring the slag includes transferring slag from the ladle directly to the slag furnace.

[0009] Some aspects can include the steps of discharging the steel free slag component from the slag pot into the slag furnace. In some such configurations, a temperature of the residual steel component is adjusted via induction current to maintain the residual steel component in a molten state. Additionally, or alternatively, the methods can include discharging the steel free slag component from the slag pot into the slag furnace and forming a modified slag material at least by mixing the steel free slag component with the one or more additives. In some configurations, the one or more additives are configured to modify a basicity index of the ladle furnace slag.

[0010] In some aspects, the slag furnace includes a chamber. The slag can be mixed with the one or more additives in the chamber and the modified slag material can be transferred from the chamber to a tundish (or other component). Some such configurations can include the step of transferring the modified slag material from the tundish to processing equipment and forming a final product. Some methods can include operating the processing equipment in a first configuration to form a first final product and wherein the final product includes granulated slag to be used such as cement or grit for blasting. Other methods can include operating the processing equipment in a second configuration to form a second final product and wherein the final product includes mineral wool. In some of the disclosed methods, discharging the modified slag material includes rotating the slag furnace via tilting mechanism. Some methods can include the steps of identifying a chemical composition of the ladle furnace slag and selecting the one or more additives based on the chemical composition of the ladle furnace slag.

[0011] Some aspects of the described features include a method of operating a slag furnace. Some such methods can include the steps of receiving, in a chamber of a slag furnace, a slag (e.g., LF slag, EAF slag, or the like), heating the chamber, and mixing, in the chamber, the ladle furnace slag with one or more additives while the ladle furnace slag is in a molten state to produce a modified slag. In some configurations, a time period from receiving the ladle furnace slag in the chamber to discharging the modified slag from the slag furnace is equal to or between 5 and 40 minutes. Some methods can include operating a movable door to cover an opening of the chamber after the ladle furnace slag is received in the chamber.

[0012] Some aspects can include a system for treating slag. The system can include a slag pot, a slag furnace, or both. Some of the described systems can include a slag pot defining a first chamber configured to receive slag from a source furnace, the slag pot including a separator configured to separate residual steel from the slag. In some configurations, the slag pot includes a pot heater configured to maintain or increase a temperature of the slag within the first chamber, a pot tilting mechanism configured to rotate the slag pot to discharge the slag from the slag pot.

[0013] Some of the described systems can include a slag furnace defining a second chamber having an opening that is configured to receive the slag from the slag pot. In some configurations, the slag furnace may have a furnace mixer coupled to or disposed within the second chamber and configured to mix the slag with one or more additives to form a modified slag, a furnace heater configured to maintain or increase a temperature of materials within the second chamber, a furnace tilting mechanism configured to rotate the slag furnace to discharge the modified slag from the slag furnace, or combination thereof. In some aspects the system can include a processing device configured to receive the modified slag from the slag furnace and produce a target product.

[0014] The term "coupled" is defined as connected, although not necessarily directly, and not necessarily mechanically; two items that are "coupled" may be unitary with each other. The terms "a" and "an" are defined as one or more unless this disclosure explicitly requires otherwise. The term "substantially" is defined as largely but not necessarily wholly what is specified (and includes what is specified; e.g., substantially 90 degrees includes 90 degrees and substantially parallel includes parallel), as understood by a person of ordinary skill in the art. In any disclosed configuration, the term "substantially" may be substituted with "within [a percentage] of" what is specified, where the percentage includes .1, 1, 5, and 10 percent.

[0015] Further, an apparatus or system that is configured in a certain way is configured in at least that way, but it can also be configured in other ways than those specifically described.

[0016] The terms "comprise" (and any form of comprise, such as "comprises" and "comprising"), "have" (and any form of have, such as "has" and "having"), and "include" (and any form of include, such as "includes" and "including") are open-ended linking verbs. As a result, an apparatus that "comprises," "has," or "includes" one or more elements possesses those one or more elements but is not limited to possessing only those elements. Likewise, a method that "comprises," "has," or "includes" one or more steps possesses those one or more steps but is not limited to possessing only those one or more steps.

[0017] Any configuration of any of the apparatuses, systems, and methods can consist of or consist essentially of - rather than comprise / include / have - any of the described steps, elements, and / or features. Thus, in any of the claims, the term "consisting of" or "consisting essentially of" can be substituted for any of the open-ended linking verbs recited above, in order to change the scope of a given claim from what it would otherwise be using the open-ended linking verb.

[0018] The feature or features of one configuration may be applied to other configurations, even though not described, or illustrated, unless expressly prohibited by this disclosure or the nature of the configurations.

[0019] Some details associated with the configurations described above and others are described below.BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The following drawings illustrate by way of example and not limitation. For the sake of brevity and clarity, every feature of a given structure is not always labeled in every figure in which that structure appears. Identical reference numbers do not necessarily indicate an identical structure. Rather, the same reference number may be used to indicate a similar feature or a feature with similar functionality, as may non-identical reference numbers. The figures are drawn to scale (unless otherwise noted), meaning the sizes of the depicted elements are accurate relative to each other for at least the configuration depicted in the figures. FIG. 1 is an illustrative schematic of a Prior Art steelmaking process. FIG. 2 is an illustrative schematic of an example of a system for handling steelmaking slag. FIG. 3 is a partial illustrative schematic of an example of a process of handling steelmaking slag according to the present disclosure. FIG. 4 is a side sectional view of an example of a slag pot of the present disclosure. FIG. 5 is a side sectional view of an example of a slag furnace of the present disclosure. FIGs. 6A to 6C illustrate an example of an operation of the slag pot and the slag furnace of FIG. 4 and FIG 5, respectively. FIG. 7 is a partial illustrative schematic of another example of a process of handling steelmaking slag according to the present disclosure. FIG. 8A is a top, plan view of another example of a slag furnace of the present disclosure. FIG. 8B is a sectional view of the slag furnace of FIG. 8A. FIGs. 9A to 9E illustrate an example of an operation of the slag furnace of FIGs. 8A - 8B. DETAILED DESCRIPTION

[0021] Referring now to FIG. 2, an example of a schematic diagram of system 100 for processing slag in a steelmaking process is shown. As described further herein, system can include a body 120 (or multiple bodies) defining an operating space 124 (e.g., one or more chambers, cavities, or the like) that is configured to receive slag. In some configurations, each body 120 may include refractory lining, water-cooled panels, or other thermal equipment to utilize the sensible heat from the slag.

[0022] As depicted, system 100 can include a stirring mechanism or mixer 128 configured to mix slag in at least a portion of operation space 124, a heater 132 configured to maintain or increase the temperature of materials within the operating space, a separator 136 configured to separate material (e.g., slag or modified slag) within the operating space into distinct elements, a transfer mechanism 140 configured to control flow of the slag from at least a portion of the operating space, or combination thereof. Although FIG. 2 depicts a single operating space 124, it will be understood that system 100 can include multiple operating spaces that can be defined by a single body (e.g., furnace) or multiple bodies. Additionally, although not depicted, system 100 can include electronics (e.g., computer, controller having a processor and a memory configured to store instructions, sensors, power sources, communications equipment, interfaces, or the like) and other means of control (load cells, thermocouples for temperature measurement, gas and fume extraction controls) that may be utilized to perform one or more of the operations described herein.

[0023] Mixer 128 is configured to homogeneously mix the material within at least a portion of operating space 124. In some configurations, mixer 128 can include a gas purging system, magnetic mixer, mechanical stirring, or the like. For example, as described in more detail below, mixer 128 can be configured to mix molten slag with one or more additives or other materials to form a modified slag. Heater 132 can be configured to operate in conjunction with mixer 128 to homogeneously mix the material. For example, heater 132 can be operated to maintain the material (e.g., slag) in a liquid or molten state. In some configurations, heater 132 can include an electric arc generating device, gas burners, or the like. In some configurations, additional materials or chemicals (e.g., silicate, alumina, silica sand, coal ash, foundry waste sand, glass chips, other alumina containing minerals, or the like )) can be added to reduce the liquidity temperature of the material so that the material within system 100 can remain in a liquid or molten state at lower temperatures. In this way and others, system 100 can operate with reduced energy or thermal demand to provide an economically viable manner of processing slag.

[0024] System 100 can be configured to separate components within the material, such as via a separator 136. In some configurations, separator 136 may assist in the separation process, such as by segregating the separate components to distinct portions of operating space 124. Separator 136 can include baffles, density based separation components, magnets, other induction current devices, or the like. In some configurations, separator 136 can be configured to separate residual steel from the slag. In some configurations, separator 136 can be a distinct component while in other configurations one or more other components of system 100 (e.g., mixer 128) can be configured to at least partially perform the separation process.

[0025] Transfer mechanism 140 can be configured to discharge the material (e.g., slag or modified slag) between distinct operating spaces (e.g., 124) or between an operating space and other components. As an illustrative, non-limiting example, transfer mechanism 140 can include a tilting mechanism configured to tip the body (e.g., furnace, ladle, or the like) to transfer material throughout system. Additionally, or alternatively, transfer mechanism 140 can include one or more controllable tap holes configured to move between open and closed states to control the discharge of the material from an operating space (e.g., 124). In some configurations, transfer mechanism 140 can include one or more controllable valves or gates configured to selectively restrict flow of a material between different portions of operating space 124. In yet other configurations, transfer mechanism 140 can include a combination of the described components with or without other known components for transferring material in the steelmaking art to convey the materials as described in the operations herein.

[0026] System 100 can be utilized to perform various steelmaking processes, such as a continuous casting steel making process. For example, referring now to FIG. 3, a process 100a for handling steelmaking slags is shown. Process 100a can correspond to an improvement on the steelmaking process shown in FIG. 1. Although described herein as a method for processing or handling ladle slag, process 100a can be utilized for treating other steelmaking slag, such as EAF slag, stainless steel slag, argon oxygen decarburization (AOD) slag, or the like.

[0027] As depicted in FIG. 3, raw material 10a (e.g., steel scrap) may be fed to a primary furnace 14a where the raw material is processed to produce molten steel 18a. In some configurations, primary furnace 14a can be a converter, electric arc furnace (EAF), induction furnace, or the like. Although not shown, primary furnace 14a may produce a slag (e.g., EAF slag) or another by-product that can be further processed. In the depicted process 100a, molten steel 18a is fed to a ladle furnace 26a that is configured to refine the molten steel 18a and produce a refined steel 30a and a ladle furnace (LF) slag 34a or ladle slag. However, a person of skill in the art should understand that the below processes can be envisioned with other secondary furnaces (e.g., 26a) and secondary furnace slags (e.g., 34a).

[0028] As described herein, system 100 is configured to process LF slag 34a in an economically viable and environmentally sustainable way. For example, in some configurations, system 100 includes a slag pot 105 and slag furnace 110a that is configured to receive LF slag 34a and perform one or more operations to process LF slag 34a, such as recapturing residual iron or steel 32a within the LF slag in slag pot 105, recycling residual steel 32a back to steelmaking process, transferring a lower steel content LF slag 34b to a slag furnace 110a, converting the LF slag 34b into usable slag material (e.g., 116), or both. LF slag 34b can be substantially free of residual steel and will have a lower steel content than LF slag 34a, as steel 32a within the LF slag 34a was removed.

[0029] As further depicted in FIG. 3, an example of slag furnace 110a is shown which can receive LF slag 34b along with other materials such as one or more additives 114 (e.g., silicate, alumina, silica sand, coal ash, foundry waste sand, glass chips, other alumina containing minerals, or the like) while processing LF slag 34b. As described further herein, slag furnace 110a can produce a modified slag 116 that can be utilized in the production of other materials, products, byproducts, or the like. For example, modified slag 116 can be used to produce a target material or product 118 (e.g., granulated slag, mineral wool, cement, abrasives, or the like) that can be stored, sold, used to make a final product, or otherwise utilized, instead of being discarded in a landfill as is done in the conventional processes. Although system 100 may include primary furnace 14a and secondary furnace 26a (e.g., the ladle furnace), it should be understood that in some embodiments the system may only include slag pot 105, slag furnace 110a, or combination thereof.

[0030] System 100 can be configured to perform one or more methods for treating slag, such as process 100a of treating LF slag 34a to produce modified slag 116. Process 100a can include recapturing residual steel in a slag pot 105, mixing LF slag 34b with one or more additives 114 in slag furnace 110a while the LF slag is in a molten state. In some configurations, additives 114 can be configured to modify the basicity index of LF slag 34b, lower the melting point of the slag, or otherwise change the characteristics of the slag. For example, a chemical composition of LF slag 34a can be identified and additives 114 can be selected based on the chemical composition of the LF slag to achieve certain characteristics in any modified slag 116 produced (e.g., to simulate the chemistry, minerology, or other characteristics of raw materials for a target product).

[0031] In some methods, process 100a can include transferring LF slag 34a obtained from ladle furnace 26a to a slag pot 105. For example, a ladle (e.g., 26b) from ladle furnace 26a can be moved for further processing. In some such methods, ladle slag 34a can be tipped into slag pot 105 by tilting the ladle (e.g., 26b) by an overhead crane or another tilting method. Residual steel within LF slag 34a can be recaptured inside the slag pot 105 by means of density and by applying induction current at the bottom part of the slag pot to ensure the collection of the residual steel in molten stage, within the LF slag at the bottom part of the slag pot 105. Residual steel free ladle slag 34b can be transferred to slag furnace 110a by tilting the slag pot 105. Residual steel 32a remaining inside the slag pot 105 after the ladle slag 34b is transferred to slag furnace 110a, can be recycled back to steelmaking process or transferred to another environment as is understood in the art.

[0032] Additives 114 can be added before, simultaneously with, or after LF slag 34b is transferred into slag furnace 110a. In configurations in which additives 114 are added before LF slag 34b, the additives can be pre-heated by slag furnace 110a to ensure the slag is maintained in a molten state. Additionally, or alternatively, a heat source (e.g., electric arc, gas burners, or the like) of slag furnace 110a can be operated to control a temperature of the slag within the slag furnace 1 10a, such as to make up for the heat losses of the slag furnace, complete the modification of LF slag 34b, maintain modified slag 116 in the molten state, discharge any material at required temperatures, or other operations. Modified slag 116 can be discharged from slag furnace 110a in molten state at required temperature into a slag runner or tundish 115 which in turn transfers the modified slag 116 to an air granulator, spinner, or another solidifying method to produce the target product 118.

[0033] Referring now to FIG. 4 another example of slag pot 105 is shown. As depicted, slag pot 105 includes an inlet 154 for receiving material and a body 120a that may be internally lined with refractory that defines an operating space 124a configured to receive slag (e.g., LF slag 34a). In some configurations, slag pot 105 can include an induction coil 132a configured to maintain or adjust a temperature of the residual steel (e.g., 32a) in a molten state . As depicted, induction coil 132a can be positioned at a lower part of body 120a (e.g., base) to keep the residual steel in a molten state. In some configurations, slag pot 105 includes a tilting mechanism 140a that is configured to discharge material from the slag pot. Tilting mechanism 140a can be moveable via gearing that is driven by electrical motors, hydraulic systems, or other suitable options known in the art. In the illustrative configuration shown in FIG. 4 depicted, slag pot 105 can receive the LF slag (e.g., 34a) including the residual steel and separate the residual steel from the LF slag by accumulating residual steel 32a at the base via density and induction current separation devices (e.g., 136). The lower steel content LF slag 34b (e.g., LF slag that is substantially free of residual steel) can then be discharged from slag pot 105 (e.g., via tilting mechanism 140a) for further processing as described herein. Molten residual steel 32a can be discharged from slag pot 105 separately from LF slag 34b. For example, LF slag 34b can be discharged into a furnace (e.g., 110a) and then slag pot 105 can be moved to discharge residual steel 32a to be recycled back into the steelmaking process. For example, residual steel 32a can be transferred into a mold or ladle (e.g., 26b) via an outlet 156. In some configurations, inlet 154 can be the same opening as outlet 156; however, in other configurations the inlets and outlets can be separate.

[0034] Referring now to FIG. 5, another example of slag furnace 110a is shown. As depicted, slag furnace 110a includes a body 120b defining an operating space 124b configured to receive slag, such as LF slag 34b from slag pot 105. In some configurations, body 120b can define one or more inlets 154 or outlets 156. Body 120b can include thermal protection and heat insulation (e.g., refractory lining, water cooled panels ) around operating space 124b to utilize the resulting heat from the molten slag received in the LF furnace 110a. This can reduce energy or thermal demand to provide an economically viable manner of processing LF slag 34a.

[0035] Operating space 124b can be configured to receive a material from a separate source (e.g., slag pot 105) and treat that material. As an illustrative example, ladle slag 34b from a slag pot 105 can be poured into an opening controlled via door 160 of furnace 110a. Door 160 can be movable between an open configuration (e.g., FIG. 6B) in which the opening of furnace 110a is exposed to the atmosphere and a closed configuration (e.g., FIG.5) in which the opening of the first chamber is covered by the door.

[0036] The material within operating space 124b can be treated to create a modified material. As an example, a heater (e.g., 132) can be configured to control a temperature of operating space 124b. Additionally, or alternatively, mixer 128 can be disposed within or coupled to operating space 124b and configured to mix a material within the chamber. In some configurations, a tilting mechanism 140b can be included in or coupled to body 120b to discharge the material through an outlet 156, such as a tap hole. In some configurations, after the material is treated in operating space 124b, the material can then be discharged through tap hole (e.g., 156) and transferred to slag runner or tundish 115. For example, modified slag 116 can be discharged from slag furnace 110a and transferred to tundish 115, which can then be input into other process machinery (e.g., cooling equipment, spinners, or the like) to further modify the material into a useable product.

[0037] Referring now to FIGs. 6A-C, an illustrative example of operation of system 100 to produce a modified slag (e.g., 116) from ladle furnace slag is shown. However, in other configurations, system 100 can process other slags, such as EAF slag, stainless steel slag, argon oxygen decarburization (AOD) slag, or the like. As shown in FIG. 6A, LF slag 34a from a ladle 26b can be transferred into slag pot 105. Ladle 26b can be the same ladle that is used in the ladle furnace (e.g., 26a). LF slag 34b and residual steel 32a can be separated inside the slag pot 105, as described herein. As shown in FIG. 6B, LF slag 34b (e.g., iron or steel free slag) can be transferred from slag pot 105 to furnace 110a. Residual iron or steel 32a can be maintained within slag pot 105 during transfer of the LF slag 34b and subsequently discharged for further processing. In some configurations, slag 34b is in a molten state and can be poured into an opening of furnace 110a by tilting slag pot 105 or via other known methods for transferring slag. In some configurations, additives 114 can be introduced into slag furnace 110a (e.g., in operating space 124b) before receiving slag 34b. In some such configurations, additives 114 can be pre-heated (e.g., via heater 132) to assist with homogenous mixture of the materials. However, in other configurations, additives can be fed into slag furnace 110a simultaneously with slag 34b or, alternatively, after the slag has been added.

[0038] In some configurations, the chemical composition of ladle slag 34b or additives 114 can be analyzed before mixing the components together. For example, some operations can include the step of sampling ladle slag 34a when the treatment at ladle furnace 26a is completed. Additionally, or alternatively, some operations may include sampling or analyzing a mixture of additives 114 (e.g., silicate or alumina containing minerals including but not limited to silica sand, coal ash, foundry waste sand, and glass chips). In some configurations, as described herein, additives can be selected based on the chemical composition of ladle slag 34a, a target material or product (e.g., 118), or both.

[0039] Referring to FIG. 6B, slag 34b and additives 114 are mixed together in operating space 124b via mixer 128 to create a homogeneous melt (e.g., 116) of the materials. In the mixing process, door 160 can be moved from the open position (FIG. 6B) to a closed position (FIG.6C). In some configurations, temperature of operating space 124b is controlled to improve mixing characteristics. For example, operating space 124b of slag furnace 110a can be heated (e.g., via heater 132) to maintain the slag 34b or slag mixture in the molten state. In some configurations, additional processing can be performed to form the modified slag from the LF slag 34b and additives 114. In some of the operations disclosed herein, the mixing process can be performed for a time period equal to or between 5 minutes to 20 minutes or any time period therebetween (e.g., between 10 to 30 minutes, between 15 to 20 minutes, etc.).

[0040] As depicted in FIG. 6C, the material can be discharged from operating space 124b by tilting slag furnace 110a via outlet 156 (e.g., tap hole) into slag runner or tundish 115. In some configurations modified slag 116 can be fed to a device 200 that can include processing equipment, a solidification unit, or the like. Device 200 can include a granulator (e.g., air cooler), spinner, or other processing equipment known in the art, depending on the target product 118 to be produced. As a non-limiting example, modified slag 116 can be air cooled by a device (e.g., 200) for granulation to be used to produce a cementitious product or can be fed to a device (e.g., 200) to produce mineral wool. In other configurations, modified slag 116 can be treated (e.g., air coiled) to produce a bulk material to be further processed by end users for other desired purposes. Modified slag 116 can be stored within furnace 110a until it is ready to be discharged and, in some configurations, one or more operations can occur while the modified slag is within the furnace.

[0041] To further illustrate this process, modified slag 116 can be processed according to different parameters depending on the final product to be produced. For example, modified slag 116 can be cooled by a high pressure air stream (e.g., via device 200) at a pressure between 150 to 500 mbar, at an air velocity between 50 m / sec to 250 m / sec, at a gas to slag ratio between 0.50 to 2.50, with a water addition between 0 to 20% by weight, and with cooling rate greater than or equal to 5°C per second, or combination thereof. For example, modified slag 116 can be cooled via an air stream at a pressure of substantially 300 mbar; at an air velocity substantially between 100 m / sec to 200 m / sec, at a gas to slag ratio between 1.00 to 2.00, by mass; with a water addition substantially between 5 to 15% by weight; and with cooling rate substantially greater than or equal to 10°C per second, or combination thereof. As shown in the Table below, the parameters applied to modified slag can be varied to obtain different target products. These parameters along with the chemical composition of modified slag 116 can be adjusted to obtain target product 118 with the desired properties. ProductPropertyAir speedGas to slag ratioWater additionMineral woolFiber150 - 200 m / sec1,50 - 2,0010% by weightCementGranules100 - 110 m / sec1,00 - 1,1010% by weightGritGranules90 - 130 m / sec0.7 - 1.2010% by weight

[0042] System 100 can be utilized to perform various steelmaking processes, such as a continuous casting steel making process. For example, referring now to FIG. 7, a process 100b for handling steelmaking slags is shown. Process 100b can correspond to an improvement on the steelmaking process shown in FIG. 1. Although described herein as a method for processing or handling ladle slag, process 100b can be utilized for treating other steelmaking slag, such as EAF slag, stainless steel slag, argon oxygen decarburization (AOD) slag, or the like.

[0043] Process 100b can include steps that correspond to process 100a, as described with respect to FIG. 3 above, with the primary difference being that slag may be transferred directly to the furnace. As depicted in FIG. 7, furnace 110b is configured to receive LF slag 34a (e.g., obtained from ladle furnace 26a) and perform one or more operations to process the LF slag, such as recapturing residual iron or steel within the LF slag, converting the LF slag into usable slag material (e.g., 116), or both. Slag furnace 110b can receive other materials such as one or more additives 114 (e.g., silicate, alumina, silica sand, coal ash, foundry waste sand, glass chips, other alumina containing minerals, or the like) while processing LF slag 34a. Slag furnace 110b can produce a modified slag 116 that can be utilized in the production of other materials, products, byproducts, or the like. For example, modified slag 116 can be used to produce a target product 118 (e.g., granulated slag or mineral wool) that can be stored, sold, used to make a final product, or otherwise utilized, instead of being discarded in a landfill as is done in the conventional processes.

[0044] Referring now to FIGs. 8A and 8B, another example of slag furnace 110b is shown. Slag furnace 110b can include or correspond to one or more components from slag furnace 110a. As depicted, slag furnace 110b includes a body 120c defining an operating space 124 that includes a first chamber 124c, a second chamber, 124d, and a first channel 152 extending between and connecting the first chamber to the second chamber. In some configurations, body 120c can define one or more inlets 154 or outlets 156. As an illustrative example, each chamber (e.g., 124c, 124d) of slag furnace 110 can, but need not, include an opening (e.g., 154) that allows communication of the chamber with the outside environment. Additionally, or alternatively, body 120c can define one or more outlets (e.g., 156) that enable fluid communication between the chambers (e.g., 124d) and the outside environment. For example, body 120c can define a first outlet 156a for discharging residual steel and a second outlet 156b for discharging modified slag. Body 120c can include thermal protection and heat insulation (e.g., refractory lining, water cooled panels, or the like) along the chambers (e.g., 124c, 124d) or channels (e.g., 152) of operating space 124 to utilize the resulting heat from the molten slag received in the chambers. This can reduce energy or thermal demand to provide an economically viable manner of processing LF slag 34a.

[0045] First chamber 124c can be configured to receive a material from a separate source and treat that material. As an illustrative example, ladle slag (e.g., 34) from ladle 26b can be poured into an opening of first chamber 124c. As best depicted in FIG. 8B, a movable door 160 can be disposed over the opening of first chamber 124c to enable selective communication of the first chamber with the outside environment. Door 160 can be movable between an open configuration (e.g., FIG. 8A) in which the opening of first chamber 124c is exposed to the atmosphere and a closed configuration (e.g., 8B) in which the opening of the first chamber is covered by the door.

[0046] The material within first chamber 124c can be treated to create a modified material. As an example, heater 132 can be configured to control a temperature of first chamber 124c and, in some configuration, a pressure source (not shown) can be configured to control a pressure of the first chamber. Additionally, or alternatively, mixer 128 can be disposed within or coupled to first chamber 124c and configured to mix a material within the first chamber. In some such configurations, separator 136 can be included in or coupled to first chamber 124c to separate components of the material out of the first chamber. In the configuration depicted in FIG. 8B, separator 136 is configured to selectively allow a component or element of the material in first chamber 124c to flow into a third chamber 124e for further processing or to be discharged through outlet 156a.

[0047] In some configurations, after the material is treated or separated in first chamber 124c, the material can then be transferred to through first channel 152 to a separate portion of operating space 124. First channel 152 can include or be coupled to a first gate 140c that is configured to selectively allow material to flow from the first channel. In an illustrative example, first gate 140c is movable between an open configuration in which material can flow from first chamber 124c through first channel 152 and a closed configuration (shown in FIG. 8B) in which material from first chamber is prevented from flowing through the first channel. In some configuration, first gate 140c is an on and off slide gate. As shown in FIG. 4B, first gate 140c can include a vertical member and a horizontal member that are configured to operate together.

[0048] Second chamber 124d is fluidically coupled to first chamber 124c through first channel 152 and can be configured to receive material from the first chamber when first gate 140c is in the open configuration. In some configurations, second chamber 124d can be configured to store the material from first chamber 124c or for further processing of the material. As depicted, second chamber 124d can be at a different elevation from first chamber (e.g., below first chamber) to encourage fluid flow between the chambers. In some configurations, one or more components from first chamber 124c can be employed in second chamber 124d, such as mixer 128, heater 132, separator 136, or combination thereof. As an illustrative example, heater 132 can be configured to control a temperature of second chamber 124d to maintain the material in the molten state.

[0049] In some configurations, second chamber 124d is in fluid communication with a second channel 176 that includes or is coupled to a second gate 140d. In some configurations, second gate 140d can include one or more components that correspond to first gate 140c. Second gate 140d may be movable to an open configuration to discharge material from second chamber 124d through outlet 156b at a controlled flow speed. As described further herein, material discharged from second chamber 124d can be input into other process machinery (e.g., cooling equipment, spinners, or the like) to further modify the material into a useable product.

[0050] Referring now to FIGs. 9A-9E, an illustrative example of operation of system 100 to produce a modified slag (e.g., 116) is shown. As shown in FIG. 9A, ladle slag 34a from a ladle 26b can be transferred into slag furnace 110 with one or more additives 114. In some configurations, slag 34a is in a molten state and can be poured into an opening of first chamber 124c by tilting ladle 26b or other known methods for transferring slag. In the depicted configuration, additives 114 are introduced into slag furnace 110 (e.g., in first chamber 124c) before receiving slag 34a. In some such configurations, additives 114 can be pre-heated (e.g., via heater 132) to assist with homogenous mixture of the materials. However, in other configurations, additives can be fed into slag furnace 110 simultaneously with slag 34a or, alternatively, after the slag has been added.

[0051] In some configurations, the chemical composition of ladle slag 34a or additives 114 can be analyzed before mixing the components together. For example, some operations can include the step of sampling ladle slag 34a when the treatment at ladle furnace 26a is completed. Additionally, or alternatively, some operations may include sampling or analyzing a mixture of additives 114 (e.g., silicate or alumina containing minerals including but not limited to silica sand, coal ash, foundry waste sand, and glass chips). In some configurations, additives can be selected based on the chemical composition of ladle slag 34a, a target product (e.g., 118), or both.

[0052] Referring now to FIG. 9B, slag 34a and additives 114 are mixed together in first chamber 124c via mixer 128 (shown in FIG 8B) to create a homogeneous melt of the materials. In the mixing process, door 160 can be moved from the open position (FIG. 9A) to a closed position (FIG. 9B). In some configurations, a pressure or temperature of first chamber 124c are controlled to improve mixing characteristics. For example, first chamber 124c of slag furnace 110 can be heated (e.g., via heater 132) to maintain the slag 34a or slag mixture in the molten state.

[0053] As shown in FIG. 9C, segregation of a residual steel component 32a can be achieved during the mixing process. For example, ladle slag 34a can include between 3 and 20%, by weight, of steel that can be separated into residual steel component 32a and lower steel content LF slag 34b during mixing. In some configurations, residual steel 32a can be separated into third chamber 124e, via separator 136, LF slag 34b remains within first chamber 124c. In this way, and others, steel material can be recovered from ladle slag 34a to increase the efficiency and economic viability of the steelmaking process.

[0054] In some operations, further processing of residual steel 32a or LF slag 34b can occur. For example, additional material (e.g., additives) can be added to one or both of the separated components. As illustrated in FIG. 9C, a carbon source (e.g., pig iron) can be added to the material to increase the carbon content. For example, carbon can be added (e.g., to LF slag 34a or residual steel 32a) until a percentage of the material is greater than or equal to a carbon threshold. The carbon threshold may be a percentage of carbon, by weight, and can be greater than or equal to 2.0% of carbon (e.g., 2.5, 3.0, 4.0, 5.0%, or greater). In the operations described herein, the liquidity temperature of residual steel 32a can be reduced for improved discharge of the residual steel. In some of the operations disclosed herein, the mixing (or separating) process can be performed for a time period equal to or between 5 minutes to 20 minutes or any time period therebetween (e.g., between 5 to 12 minutes, between 15 to 20 minutes, etc.).

[0055] As depicted in FIG. 9D, the material can be transferred away from first chamber 124c. As shown, first gate 140c disposed in first channel 152 can be operated or actuated to an open position in which LF slag 34b is able to flow into second chamber 124d through the first channel.

[0056] As a non-limiting example, a vertical member of gate 140c can be raised to allow the material to flow into first channel 152. In some configurations, a portion of first chamber 124c, first channel 152, or both can be inclined to encourage modified slag 116 to travel toward second chamber 124d. LF slag 34b can be stored within second chamber 124d until it is ready to be discharged and, in some configurations, one or more operations can occur while the LF slag 34b is in the second chamber to form the desired modified slag (e.g., 116). In another example, LF slag 34b can correspond to modified slag 116.

[0057] Further, as described above, residual steel 32a can be transferred from first chamber 124c during the mixing process. The residual steel 32a can then be discharged from slag furnace 110 via outlet 156a in fluid communication with third chamber 124e. In some operations, such as those where a carbon content of residual steel 32a is greater than the carbon threshold, a discharge temperature of the residual steel can be kept below a discharge temperature threshold (e.g., less than or equal to 1500, 1450, 1400 °C). The residual steel 32a can be stored or transferred to another environment as is understood in the art.

[0058] Referring now to FIG. 9E, modified slag 116 can be discharged from second chamber 124d. In the depicted configuration, a second gate 140d disposed in second channel 176 can be actuated to an open position in which modified slag 116 is able to flow through outlet 156b. In some configurations, modified slag 116 can be fed to device 200, such as a granulator (e.g., air cooler) or spinner, to produce target product 118. As a non-limiting example, modified slag 116 can be air cooled by device 200 for granulation to be used to produce a cementitious product (e.g., 118) or can be fed to spinners (e.g., 200) to produce mineral wool (e.g., 118).

[0059] The above specification and examples provide a complete description of the structure and use of illustrative configurations. Although certain configurations have been described above with a certain degree of particularity, or with reference to one or more individual configurations, those skilled in the art could make numerous alterations to the disclosed configurations without departing from the scope of this invention. As such, the various illustrative configurations of the methods and systems are not intended to be limited to the particular forms disclosed. Rather, they include all modifications and alternatives falling within the scope of the claims, and configurations other than the one shown may include some or all of the features of the depicted configurations. For example, elements may be omitted or combined as a unitary structure, connections may be substituted, or both. Further, where appropriate, aspects of any of the examples described above may be combined with aspects of any of the other examples described to form further examples having comparable or different properties and / or functions and addressing the same or different problems. Similarly, it will be understood that the benefits and advantages described above may relate to one configuration or may relate to several configurations. Accordingly, no single implementation described herein should be construed as limiting and implementations of the disclosure may be suitably combined without departing from the teachings of the disclosure.

[0060] The previous description of the disclosed implementations is provided to enable a person skilled in the art to make or use the disclosed implementations. Various modifications to these implementations will be readily apparent to those skilled in the art, and the principles defined herein may be applied to other implementations without departing from the scope of the disclosure. Thus, the present disclosure is not intended to be limited to the implementations shown herein but is to be accorded the widest scope possible consistent with the principles and novel features as defined by the following claims. The claims are not intended to include, and should not be interpreted to include, means-plus- or step-plus-function limitations, unless such a limitation is explicitly recited in a given claim using the phrase(s) "means for" or "step for," respectively.EXAMPLES

[0061] The present invention will be described in greater detail by way of specific examples. The following examples are offered for illustrative purposes only and are not intended to limit the invention in any manner. Those of skill in the art will readily recognize a variety of noncritical parameters that can be changed or modified to yield essentially the same results.EXAMPLE 1 Modification of Ladle Furnace Slag for Use in Cementitious Material

[0062] Ladle furnace slag (e.g., 34a) was obtained from a ladle furnace after a steelmaking process. The ladle furnace slag ("LF slag") was maintained in a molten state and mixed with silica sand and glass chips (e.g., 114) in a high temperature furnace (e.g., 110) at 1450 degrees Celsius (°C). Two samples with different compositions were selected and were prepared. The estimated and actual chemical composition (% by weight) of the LF slag, silica sand, and glass chips are included in TABLES 1 and 2, below. TABLE 1: Chemical Composition of Sample 1 Material (%)CaOSiO 2 MgOAl 2 O 3 Fe 2 O 3 NA 2 O + K 2 OSO 3 BasicityLF Slag73%51.016.06.018.06.00.601.03.2Silica25%0.199.3-0.30.2---Glass2%10.073.04.01.0-12.0--Modified LF Slag - Calculated37.538.04.513.24.40.70.70.99Modified LF Slag - Actual42.437.93.615.65.30.50.21.12 TABLE 2: Chemical Composition of Sample 2 Material (%)CaOSiO 2 MgOAl 2 O 3 Fe 3 O 3 NA 2 O + K 2 OSO 3 BasicityLF Slag83%51.016.06.018.06.00.601.03.2Silica15%0.1099.30-0.30.20---Glass2%10.0073.004.001.00-12.00--Modified LF Slag - Calculated42.529.65.115.05.00.70.81.44Modified LF Slag - Actual42.430.24.216.75.30.40.21.40

[0063] The bottom row of TABLES 1 and 2, above, shows the actual chemical composition of the formed modified LF slag (e.g., 116) resulting from the mixture of the LF slag, silica sand, and glass chips. The results are relatively similar to the estimated or calculated results for the composition of the modified slags. As shown, the basicity index of the resulting modified LF slag can be lower than the initial LF slag. The lower basicity index, among other things, helps decrease the liquidity temperature so the modified LF slag can be maintained in the molten state at lower temperatures that the original LF slag.

[0064] The two samples of the modified LF slag were then cooled by a high pressure air stream at pressure 300 mbar at between 100 m / sec to 110 m / sec air velocity and gas to slag ratio between 1.00 to 1.10 with cooling rate higher than 10 °C per second by purging water in air stream having %10 by weight water to slag ratio . Two resulting materials (e.g., granulated material) were obtained after cooling the two respective samples of modified LF slag. The first resulting material, obtained from Sample 1, was formed by a high pressure air stream at pressure 300 mbar at 110m / sec air velocity and gas to slag ratio at 1.10 with 10% water purging in air stream. The second resulting material, obtained from Sample 2, was formed by a high pressure air stream at pressure 300 mbar at 100m / sec air velocity and gas to slag ratio at 1.0 with 10% water purging in air stream. After cooling, various different properties of the Samples, such as glassy phase chemistry, activity index for the compressive strength, setting time, were measured and compared to the Turkish Standards for utilizing granulated blast furnace slag in concrete, mortar, and grout (TS EN 15167-1) and for cement (TS EN 197-1). The observed properties of first resulting material (Sample 1) and the second resulting material (Sample 2) were then compared with the limit values of the Turkish Standards as shown in Table 3, below: TABLE 3: Comparison of Resulting Material with Turkish Composition Standards % PropertySample 1Sample 2TS EN 15167-1 Limit values (Concrete)TS EN 197-1 Limit Value (Cement)Loss of Ignition<0.01<0.01Max. 3.0-SiO237.9430.17--Al2O315.6316.74--Fe2O35.335.25--CaO36.2642.37--MgO3.554.11Max. 18-SO30.150.12Max. 2.5-Na2O0.460.42--K2O0.070.02--TiO20.240.19--S-20.100.12Max. 2.0-Cl-0.00750.0004Max. 0.1-Glass Phase*93,3190,40Min 66,7Min. 66.67CaO+MgO+SiO277.7576.65-Min. 66.67(CaO+MgO) / SiO21.051.54-> 1.0*Although the glassy phase value is not provided in the standard, the definition of blast furnace slag requires the material "contain[] at least 2 / 3 of glassy slag by mass," which corresponds to 66.67%.

[0065] As shown in TABLE 3, both Samples meet the composition requirements of the Turkish Standards to be utilized in Concrete and Cement. Several tests were then performed on the first resulting material (Sample 1) and the second resulting material (Sample 2) and the results of these tests were compared with the Turkish standards for the use of blast furnace slags in concrete, mortar, and grout (TS EN 15167-1). The results of the tests as well as the Turkish standards are shown in TABLE 4, below: TABLE 4: Comparison of Resulting Material with Turkish Testing Standards TestUnitSAMPLE 1SAMPLE 2TS EN 15167-1 LimitsTest MethodDensity (3)2.962.97-KKB.TA.09 İ In-house Method (Digital Pycnometer)7 days Activity index (3)%60.290.3Min. 45TS EN 15167-1 / EN 15167-1Compressive Strength 7 days (1)(3)MPa24.837.2-TS EN 196-1 / EN 196-1Compressive Strength 7 days (2)MPa41.241.2-TS EN 196-1 / EN 196-1Compressive Strength 28 Gün (1)(3)MPa47,561,9-TS EN 196-1 / EN 196-1Compressive Strength 28 days (2)MPa49,949,9-TS EN 196-1 / EN 196-128 days Activity index (3)%95,2124Min 75TS EN 15167-1 / EN 15167-1Cement setting time starts at (1)(3)minutes300310(4)TS EN 196-3 / EN 196-3Cement setting time ends at (1)(3)minute370365-TS EN 196-3 / EN 196-3(1) Analysis was performed with 50% sample + 50% reference cement mixture.(2) The analysis was performed with 100% reference cement sample(3) The sample was ground to a fineness of 4500±100 cm2 / g in a laboratory type ball mill.(4) The setting starting time of the cement paste prepared with 100% test cement is 210 minutes. The start of setting time of the paste of the mixture prepared according to TS EN 15167-1 standard should not be more than 2 times the setting start time of the cement paste prepared with 100% test cement.

[0066] As shown in TABLE 4, both Samples comply with the specifications set forth in the Turkish Standards to be utilized in Concrete. Accordingly, contrary to the conventional process where the LF slag is buried in a landfill, the LF slag of the disclosed operations can be converted to a useable material that can be utilized to produce cementitious material, providing both environmental and economic benefits over conventional operations. This material properties of the target product are shown to meet the standards for use in multiple applications.EXAMPLE 2 Modification of Ladle Furnace Slag for Use in Mineral Wool Products

[0067] In another example, the same LF slag (e.g., 34a) was mixed with silica sand, coal ash, and glass chips (e.g., 114) in a high temperature furnace (e.g., 110) at 1450 °C. The chemical composition (% by weight) of the LF slag, silica sand, coal ash (e.g., fly ash), and glass chips are included in TABLE 5, below. TABLE 5: Chemical Composition of Materials Material (%)CaOSiO 2 MgOAl 2 O 3 Fe 2 O 3 NA 2 O + K 2 OSO 3 BasicityLF Slag53%51.016.06.018.06.00.601.03.2Fly Ash40%4.355.22.843.05.33.81.6-Silica5%0.199.3-0.30.2---Glass2%10.073.04.01.0-12.0--Modified LF Slag29.097.04.426.85.32.11.20.78

[0068] The bottom row of TABLE 5, above, shows the chemical composition of the formed modified LF slag (e.g., 116) resulting from the mixture of the LF slag, silica sand, fly ash, and glass chips. Again, the basicity index of the resulting modified LF slag in lower than the initial LF slag As compared to the modified LF slag of Example 1, it can be seen that the addition of coal ash (in the form of fly ash) results in a modified LF slag with a much lower calcium oxide (CaO) content and a much higher silicon dioxide (SiO 2 ) content. The aluminum oxide content was also increased with the addition of coal ash.

[0069] The modified LF slag was then cooled by a high pressure air stream at pressure 300 mbar at between 150 m / sec to 200 m / sec air velocity and gas to slag ratio between 1.50 to 2.0 with cooling rate higher than 10 °C per second by purging water in air stream having 10% by weight water to slag ratio. The resulting material (e.g., 118) after cooling was fiberized having chemistry, minerology, and characteristics (e.g., sound absorption, thermal conductivity, fiber diameter) similar to mineral fiber that is used in mineral wool products. As explained above, the processing of LF slag can produce useable materials that provide environmental, economical and efficiency improvements over the prior art.EXAMPLE 3 Modification of Electric Arc Furnace Slag for Use in Grit Products

[0070] In another example, EAF slag was mixed with silica sand, , and glass chips (e.g., 114) in a high temperature furnace (e.g., 110) at 1450 °C. The chemical composition (% by weight) of the EAF slag, silica sand, and glass chips are included in TABLE 6, below. TABLE 6: Chemical Composition of Material Material (%)CaOSiO 2 MgOAl 2 O 3 Fe 2 O 3 EAF Slag89%1920.0.09,717,034Silica9%0.199.3-0.30.2Glass2%10.073.04.01.0-Modified LF Slag - Calculated17.128.28.715.230.3Modified LF Slag - Actual16.327.08.715.530.8

[0071] The bottom row of TABLE 6, above, shows the chemical composition of the formed modified EAF slag (e.g., 116) resulting from the mixture of the EAF slag, silica sand, and glass chips. The results are relatively similar to the estimated or calculated results for the composition of the modified slag. Thus, as described herein, it is possible to select additives based on the desired properties of the final products with confidence.

[0072] The modified EAF slag was then cooled by a high pressure air stream at pressure 300 mbar at between 90 m / sec to 130 m / sec air velocity and gas to slag ratio between 0,70 to 1,20 with cooling rate higher than 10 °C per second by purging water in air stream having %10 by weight water to slag ratio . The resulting material (e.g., 118) after cooling was a granulated material having physical characteristics and environmental requirements (e.g., mohs hardness (>8), blasting strength, abrasion resistance, low dust emission) similar to grit products such as nickel slag which has Mohs hardness in between 6 and 7 that are typically used in blasting applications. As explained above, the processing of EAF slag, as described herein, can produce useable materials that provide environmental, economical and efficiency improvements over the prior art.

[0073] As illustrated by the above examples, the characteristics of the material produced can be determined by the chemical composition of the modified steelmaking slag. As explained herein, the characteristics of the steelmaking slag and additives can be determined before a mixing operation is performed so that the chemical composition of the modified steelmaking slag can be better controlled and can form a useful product. These examples should not be seen as limiting and are merely an illustration that the modified ladle slag can have multiple, different uses depending on its resulting characteristics.

Claims

1. A method of treating steelmaking slag comprising: transferring slag from a ladle to a slag furnace; and mixing the slag with one or more additives in the slag furnace; wherein the slag is in a molten state within the slag furnace.

2. The method of claim 1, further comprising pre-heating the one or more additives within the slag furnace prior to transferring the slag to the slag furnace.

3. The method of claim 1 or 2, wherein the step of transferring the slag includes: transferring the slag from the ladle to a slag pot; separating the slag into a residual steel component and a slag component that is substantially free of steel; and transferring the slag component from the slag pot to the slag furnace.

4. The method of claim 1 or 2, wherein the step of transferring the slag includes transferring a ladle furnace slag from the ladle directly to the slag furnace; and the method further comprises, after the step of transferring the slag, the step of separating the slag into a residual steel component and a slag component that is substantially free of steel.

5. The method of claim 3, further comprising the step of: discharging the residual steel component from the slag pot into a ladle to recycle the residual steel component; wherein: a temperature of the residual steel component is adjusted via induction current to maintain the residual steel component in a molten state.

6. The method of any preceding claim, further comprising the step of forming a modified slag material at least by mixing the slag component with the one or more additives.

7. The method of any preceding claim, wherein: the slag is a ladle furnace slag; and the one or more additives are configured to modify a basicity index of the ladle furnace slag.

8. The method of claim 6, wherein: the slag furnace includes a chamber; the slag is mixed with the one or more additives in the chamber; and the method further comprises the step of transferring the modified slag material from the chamber to a tundish.

9. The method of claim 8, further comprising the step of transferring the modified slag material from the tundish to processing equipment and forming a final product.

10. The method of any preceding claim, wherein the slag is a ladle furnace slag and the method further comprises the steps of: identifying a chemical composition of the ladle furnace slag; and selecting the one or more additives based on the chemical composition of the ladle furnace slag.

11. The method of claim of claim 6, further comprising: cooling the modified slag at: a pressure of substantially 300 mbar; and an air velocity of between substantially 150 to 200 m / sec; and a mass ratio of gas to slag of between 1.50 to 2.00; and wherein the cooled modified slag includes between 5 to 15% water, by weight.

12. The method of claim of claim 6, further comprising: cooling the modified slag at: a pressure of substantially 300 mbar; and an air velocity of between substantially 100 to 110 m / sec; and a mass ratio of gas to slag of between 1.00 to 1.10; and wherein the cooled modified slag includes between 5 to 15% water, by weight.

13. A method of operating a slag furnace, comprising: receiving, in a chamber of a slag furnace, a ladle furnace slag; heating the chamber; and mixing, in the chamber, the ladle furnace slag with one or more additives while the ladle furnace slag is in a molten state to produce a modified slag.

14. The method of claim 13, wherein a time period from receiving the ladle furnace slag in the chamber to discharging the modified slag from the slag furnace is equal to or between 5 and 40 minutes.

15. A system for treating slag comprising: a slag pot defining a first chamber configured to receive slag from a source furnace, the slag pot including a separator configured to separate residual steel from the slag; and a slag furnace defining a second chamber having an opening that is configured to receive the slag from the slag pot; the slag furnace including: a furnace mixer coupled to or disposed within the second chamber and configured to mix the slag with one or more additives to form a modified slag; a furnace heater configured to maintain or increase a temperature of materials within the second chamber; and a furnace tilting mechanism configured to rotate the slag furnace to discharge the modified slag from the slag furnace.

16. The system of claim 15, wherein the slag pot includes: a pot heater configured to maintain or increase a temperature of the slag within the first chamber; a pot tilting mechanism configured to rotate the slag pot to discharge the slag from the slag pot via a tap hole.

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