Silicothermic reduction system and process

Abstract

A process and system for adjusting chemistry of a ferrous metallurgical processes, including a hot metal in an integrated steelmaking plant. The system and process comprises receiving a molten ferrous material comprising a high silicon content in a ladle station downstream of a furnace, for example downstream of an electric smelting furnace. Chemistry of the molten ferrous material may be adjusted by adding an oxide thereto. The oxide may be solid or gaseous. The gaseous oxide may be recycled from elsewhere in the plant (such as an integrated steelmaking plant), for example, collected from off-gas. The oxide may be bubbled or injected into the molten ferrous material to reduce silicon in the molten ferrous material to form slag with SiO2. Carbon in the molten ferrous material may also be increased when the oxide comprises an element of carbon.

Description

SILICOTHERMIC REDUCTION SYSTEM AND PROCESSFIELD

[0001] The present invention relates to metal chemistry in ferrous metallurgical processes, including hot metal chemistry in steelmaking and iron making processes.BACKGROUND

[0002] Ferrous metallurgical industries (such as the iron and steel making industry) have long relied on blast furnaces to produce their desired metals. In the case of the iron and steel making industry, they have relied on blast furnaces to produce steel from iron oxides. Such use of blast furnaces, however, produce, high carbon emissions as compared to other developing methods in the industry. For example, the Blast Furnace - Basic Oxygen Furnace (BF-BOF) route to making steel produces more than 5 times the amount of CO2 as compared to, for example, the Electric Arc Furnace (EAF) route using scrap.

[0003] To help reduce carbon emissions many steel producers, for example, are replacing blast furnaces with direct reduced ironmaking using direct reduced iron (DRI). Some steel producers have turned to melting DRI with an electric arc furnace (EAF) to produce steel directly, while others are considering smelting DRI in a fixed electric smelting furnace (ESF) to produce hot metal (also referred to as molten pig iron or molten iron) that is refined into steel in basic oxygen furnaces (BOF). Sustainability drivers for the DRI-ESF-BOF process route include reduced greenhouse gas emissions, the ability to use blast furnace grade iron ore, and to avoid stranding existing BOF steelmaking assets. In some cases, iron making processes use ESF alone to produce pig iron that is processed into solid and sold or further processed downstream. However, the ESF process itself still produces greenhouse gases.

[0004] Although conventional electric smelting furnaces and processes produce, on average, lower greenhouse gas emissions as compared to blast furnaces, such furnaces and processes are not yet at a desirable near zero greenhouse gas emission. In addition, as observed by the inventors, the composition of the molten ferrous material (such as hot metal) from the ESF is not the same compared to the molten ferrous material from a blast furnace. For example, the composition of hot metal from an ESF may comprise a lower energy density as compared to hot metal from a blast furnace.

[0005] As the ferrous metallurgical industries move towards lower greenhouse gas emissions, there is an ongoing need for processes that have reduced greenhouse gas emissions, or can achieve near zero greenhouse gas emissions, but still produce molten ferrous material (also referred to herein as ferrous melt) similar in composition to that produced by a blast furnace.BRIEF DESCRIPTION OF THE FIGURES

[0006] FIG. 1 is a process flow diagram for adjusting the chemical composition of a ferrous melt in accordance with an embodiment of the present disclosure.

[0007] FIG. 2 is a system for adjusting a ferrous melt chemistry in accordance with an embodiment of the present disclosure.DETAILED DESCRIPTION

[0008] Conventional molten ferrous material produced by an ESF is expected to and may contain a higher silicon and lower carbon content as compared to molten ferrous material from a blast furnace. For example, conventional ESF hot metal is expected to and may contain a higher silicon and lower carbon content as compared to hot metal from blast furnaces. Accordingly, although the conventional ESF produces less greenhouse gases, the ESF ferrous melt composition is not as favorable for the downstream processes (such as steelmaking processes in the case of hot metal) as ferrous melt would be from a blast furnace.

[0009] With respect to hot metal and steel making processes, high silicon in the ESF hot metal may lead to increased slag volume during the BOF steelmaking, and consequently higher cost and yield loss. In addition, carbon in the hot metal from the ESF is also likely to be lower than saturation level due to the lack of a large carbon mass which drives carburization in the blast furnace. Consequently, hot metal from the ESF provides less energy input to the BOF downstream, and limits scrap usage, which in turn may affect final steel emissions and cost.

[0010] In an example comparison, the blast furnace hot metal may be saturated with approximately 4.5% carbon and contain relatively low silicon (for example, approximately 0.3-0.4%). Whereas the ESF hot metal is likely to contain a lower carbon content, for example 2-3.5%, depending on the direct reduced iron used, and higher silicon content, for example, greater than about 0.6%.

[0011] According to embodiments as described herein, a process for hot metal chemistry adjustments is provided. The process comprises adjusting the hot metal chemistry by silicothermic reduction. Silicothermic reduction may be described as a redox chemical reaction using silicon as the reducing agent at high temperature. In an example, the hot metal may be received or tapped from an ESF. In another example, the hot metal may be obtained from other sources such as other upstream furnaces or industrial processes. In an example, the upstream furnace may be electric, or gas fired or otherwise powered such as to reach temperatures that produce silicon in the hot metal.

[0012] In an example embodiment, pre-reduced iron or DRI (direct reduced iron) may be added to an ESF to produce a hot metal. The DRI may include one or more of reduced and unreduced iron, gangue and flux binders. The ESF feed may include DRI as well as other reductants and / or fluxes such as anthracite or limestone. The DRI may be in the form of fines, pellets, briquettes, or any other suitable form and may contain silica (SiC ). In an example, the DRI may contain Fe, FeO and SiC>2. At least a portion of the feed for the ESF or furnace that produces the hot metal, includes silica. For example, fluxes in the ESF feed may contain silica and / or the DRI may contain silica. As melting occurs in the high temperatures of the ESF or other furnace, at least some SiC>2 in the slag is reduced by a reductant, for example carbon, to produce Si which reports to the hot metal.

[0013] The higher silicon in the ESF hot metal, for example, may be due to the silicon formation which occurs in the very high temperature zones around electrodes as a product of unintentional reduction of SiC>2 (silica) in the slag. By reducing silica into silicon, energy from the furnace may be stored in the silicon. Silicon reports to the hot metal thereby increasing the silicon content in the hot metal.

[0014] In an example, a hot metal with an elevated or high silicon content may be tapped from the ESF or obtained from another system or furnace. An elevated or high silicon content may be for example a silicon content greater than that which would be observed in a hot metal from a blast furnace. In an example, the silicon content may be greater than about 0.6%.

[0015] The hot metal (which may be referred to herein as a first hot metal, or more generally as a first ferrous melt) may be collected in, received in, or provided to a ladle station, for example a torpedo car, ladle, iron pot, or other hot metal collection or treatment vessel such as a Kanbara Reactor (KR). The ladle station may be near or adjacent to thefurnace or elsewhere in the integrated system, such as in a separate refining system, such that hot metal from the furnace may be received by the ladle station.

[0016] An oxide, which comprises oxygen, is added to the hot metal to produce a hot metal with a second silicon content (which may also be referred to herein as a second hot metal, or more generally as a second ferrous melt), the second silicon content being lower than the silicon content of the hot metal before the addition of the oxide. The hot metal with the lower silicon content may also comprises an increased content of the element. The oxide may be provided to the hot metal in the ladle station. The oxide may be O2, alone, and / or oxygen bound with another element. In an example, carbon monoxide (comprising oxygen bound to a carbon) may be added as the oxide to the high silicon content hot metal in the ladle station to produce a hot metal with a lower silicon content and increased carbon content. Silicon in the hot metal may act as an energy source or reductant source such that the silicon’s oxidation releases the energy stored in the silicon and forms oxides of silicon as products. The oxide may be added as a solid, molten I liquid or gas, and may be for example of intermediate stability. One or more types of oxides may be used simultaneously or sequentially. The oxide may be, for example, CO where the other element is carbon, or MnO where the other element is manganese. In other examples, the oxide may be V2O3 or C^Os where the other element is Vanadium or Chromium, respectively. In other examples, the oxide may comprise gaseous oxygen, a blend of any one or more of O21 CO I CO2, and / or oxides of iron (such as FeO, Fe2O3, FesO^. In other examples, CO in any blend with other oxides and inert gases may be added to the hot metal, including, a combination of CO and CO2; a combination of CO and CO2 and N2; and / or a combination of CO and N2. The aforementioned oxide examples are provided as an example and are not meant to be limiting. For example, an oxide from a less electrochemically active element as compared to silicon, for example an element that is lower than silicon on the electrochemical series, may be used. In each case however, the oxide is configured to oxidizes the silicon, and optionally simultaneously increasing the content of an element in the hot metal when the oxide comprises another element (such as carbon, manganese, etc.). For example, MnO may be used to oxidizes silicon while enhancing the manganese content in the hot metal, and CO may be used to oxidizes silicon while carburizing the hot metal.

[0017] When CO is used as an oxide, it may be collected from off-gas from the ESF or any other process operation that contains CO, for example BOF, coke ovens, ladle metallurgy furnace (LMF), blast furnace (BF), gasifiers, and / or re-heat furnaces. Any furnace,steel, or other industrial operation that produces CO bearing off-gas may be used for the collection of the off-gas for use as an oxide in the process as described herein. In an example, furnace off-gas may be collected and further processed to remove at least a portion of CO2 and N2, such as to leave a majority of CO available for addition into the hot metal. For example, the CO content may be 95% while the CO2content may be 5%. To minimize iron losses it may be desirable for the off-gas being injected to have substantially higher CO than CO2 due to each such oxidant's relative oxidation potential. In particular, CO2has a higher oxidation potential as compared to CO and can be expected to lead to greater iron losses, which is undesirable. Although CO would also comprise a lower oxidation potential as compared to CO2 with respect to silicon resulting in silicon remaining in the hot metal, this may not be detrimental or may have some advantages in the present process as compared to certain conventional processes. Conventional silicon reduction or desiliconization that occurs during steelmaking may accept removal of Silicon at the expense of iron loss in order to ensure that no significant silicon content remains in the final steel product. Silicon content remaining in the hot metal however may be acceptable according to embodiments of this disclosure as the hot metal is further treated downstream in a steelmaking process, for example in a downstream BOF that uses the silicon as fuel. Injecting a substantial amount of CO as compared to CO2 into the hot metal may therefore reduce iron loss and increase carbon content in the hot metal, but still be acceptable as a result of the process of the subject application not having the same silicon constraints as in conventional methods. In another example, CO may be collected from other sources such as from conversion of charcoal or may be purchased directly.

[0018] In an embodiment, CO may be used in combination with CO2, however the molar ratio of CO to CO2must be greater than 1, preferably greater than 1.5. For example, a gas being added to the hot metal may comprise less than molar 40% of CO2, for example, less than 20%. The relative amounts of the combination of CO / CO2 in a gas added to the hot metal may be adjusted to control the oxidizing potential of the additive to the hot metal such as to oxidizes the desired amount of silicon into silica while minimizing the oxidation of iron in the hot metal. In some cases, it may be desirable to maintain some silicon for use in downstream basic oxygen furnace processes which may be fueled by silicon. Other gases, such as inert gases, for example argon and nitrogen, may also be injected or added into the hot metal along with CO or along with a combination of CO / CO2, where the CO:CO2molar ratio is greater than 1. In another example, inert gases may be added to the hot metal incombination with solid oxides such as MnO, O2O3 and / or V2O3. The inert gas may be a carrier gas.

[0019] The oxide may be added by injection or bubbling, for example. In an example, CO may be added by CO bubbling, and solid MnO may be added by injection with an inert gas, for example a transport or carrier gas. MnO may also be added by injection with CO or with a combination CO / CO2. The oxide may be any one or more iron oxides, such as FeO, Fe2O3, Fe3O4.

[0020] CO may simultaneously carburize and desiliconize the hot metal when bubbled or injected into the hot metal (HM), for example according to the following formula:2CO(g) + Si(HM) = SiO2(slag) + 2C(HM) , AH<0

[0021] Other oxides, such as MnO, can also be used to reduce silicon in the hot metal and increase manganese for certain steel grades, for example according to the following formula:2MnO(S) + Si(HM) = SiO2(siag) + 2Mn<HM) , AH<0

[0022] In an example, a lance may be used for injection by lowering the lance into the hot metal. The lance may comprise a shape and injection velocity that ensures that the oxides report to the hot metal. In an example, the lance may be a co-axial lance. For example, the co-axial lance may inject a solid bearing stream in the center with CO stream on the outside. The solid bearing stream may be accompanied by a small amount of an inert or carrier gas such as the CO stream or another gas or combination of gases. Lower amounts of the inert or carrier gas may be preferred since high volume of gas leads to bubbles and / or splashing and the ladle or torpedo car has limited freeboard size.

[0023] In an example, the injection may be a multi-stage injection of different gas blends. For example, the injection may be started by expelling or blowing an inert gas from the lance, such as argon or nitrogen for example, before the lance is lowered into the hot metal. Once the lance is moved towards the hot metal, the lance is a select distance from the hot metal, or the lance is lowered into the hot metal, the lance can be switched to blowing or expelling CO or a combination of CO / CO2 where the ratio of CO:CO2 is greater than 1, and once the lance is raised out of the hot metal, it may be switched back to expelling or blowing the inert gas. In this way, CO is only blown out of the lance while the lance is proximate to or in the hot metal thereby helping prevent excessive CO from being blown into the atmosphere which may pose a health risk. In other cases, the composition and velocity of the injectionmay be altered at different times in order to manage the composition, for safety and / or for efficiency.

[0024] In an example, CO bubbling may be accomplished as bottom purging via a porous plug in the vessel. A porous plug is a porous ceramic purger typically used at the bottom of a vessel or on the side below the metal bath to inject gas at relatively low velocity and bubble the gas into the melt. CO bubbling is typically conducted at a lower velocity as compared to injection.

[0025] The addition of an oxide to the hot metal in the ladle station may also produce a by-product comprising an oxide of silicon, for example SiO2 or SiO. For example, a slag may be produced as a by-product of the process, the slag comprising SiC>2. In another example, a by-product stream such as off-gas or fume comprising SiO or SiO2 may be produced. In an example, only one or both oxide states of silicon may be produced. The byproduct stream may be separated from the hot metal stream. In an example, by-product slag in the ladle station may be skimmed off the top of the hot metal by conventional slag skimming means.

[0026] Additional reagent and / or flux may also be added to the hot metal in the ladle station. The additional reagent and / or flux unit may be used to further adjust the hot metal chemistry. For example, the additional reagent or flux may be used to aid in desiliconization of the hot metal or aid in formation of liquid slag. In an example, the additional reagent and / or flux may comprise CaC2, CaF2, AI2O3, and / or CaO. The additional reagents and / or fluxes may comprise any one or more iron oxides, such as FeO, Fe2Os, FesC

[0027] The chemistry adjusted hot metal stream (with or without additional reagents and / or flux) comprising a lower silicon content compared to the hot metal before addition of oxides may be directed, after chemistry adjustment, to a granulation or solidification stage or other downstream processes, such as to a BOF for steelmaking.

[0028] A system for ferrous melt chemistry adjustment as disclosed herein may comprise an upstream furnace, such as an electric smelting furnace, a ladle station and an oxide addition unit, for example one or more of a carbon monoxide, manganese oxide, chromium oxide and vanadium oxide addition unit. The oxide addition unit may be configured to add CO, MnO, C^Ch, V2O3, or a combination of these oxides or any other oxides with or without inert gases I additional reagents, wherein the oxide is configured to oxidizes the silicon while optionally simultaneously increasing in the ferrous melt the content of the element that is bound with the oxide, if any. The system may be retrofit to an existing ESF-BOF integrated plant or any other ferrous metallurgical plant, for example, or to any other suitable integrated steelmaking plant. In an example, the ladle station is near or adjacent to the upstream furnace such that the ferrous melt (such as hot metal) from the upstream furnace may be directly sent to the ladle station from the upstream furnace. The oxide addition unit may be integrated with or capable of interacting with, or in fluid communication with, the ladle station such as to add oxides to the ladle station.

[0029] The upstream furnace may be an ESF or any furnace that can produce a ferrous melt (such as hot metal) and may be electric, or gas fired or otherwise powered such as to reach temperatures that produce silicon in the ferrous melt. In an example, the upstream furnace feed stream comprises silica. For example, silica may be present in DRI (or pre-reduced oxides), or in other feed components such as flux.

[0030] The ladle station may be for example a torpedo car, ladle, iron pot, transfer car, or other hot metal collection vessel such as a Kanbara Reactor (KR). The ladle station may be near or adjacent to the furnace such that ferrous melt (such as hot metal) from the furnace may be directly received by the ladle station. For example, the ladle station may be connected to a ferrous melt tap hole of the upstream furnace. In another example, the ladle station may also be a stand-alone area with transport of ferrous melt from an upstream furnace and further transport to other downstream processes. The ladle station may be connected to downstream further processing, for example, to a downstream granulation or solidification step for hot metal or to a downstream BOF.

[0031] The oxide addition unit may be used to add solid or gaseous oxides to the ferrous melt received in the ladle station. The oxide addition unit may be, for example, a lance. The lance may be used to inject solid oxide particles with a carrier gas, into the ferrous melt . The lance may be shaped and configured at an injection velocity that directs the oxides to report to the ferrous melt . In an example, the lance may be a co-axial lance. For example, the co-axial lance may inject a solid bearing stream in the center with a CO or other gaseous stream as a carrier gas on the outside. Lower amounts of transport or carrier gas may be preferred since high volume of gas leads to bubbles and / or splashing and the ladle station, such as a torpedo car, may have limited freeboard size.

[0032] The oxide addition unit may be integrated with the ladle station as a porous plug configured to bubble gaseous oxide into the hot metal from the bottom of the ladle. The gaseous oxide may be, for example, carbon monoxide.

[0033] The oxide addition unit may be connected to an air separation unit. The air separation unit may be connected to an off-gas collection from elsewhere in the system. For example, the air separation unit may be connected to the off-gas collection from the upstream furnace or any other furnace in an integrated steelmaking plant. In an example, the off-gas may be collected from a steelmaking furnace downstream of the upstream furnace. The air separation unit separates off-gases from various sources to extract gaseous oxides. For example, the air separation unit may separate CO2 and N2from CO, such that only CO is sent to the ladle station. In an example, the air separation unit is a reverse water gas shift reactor or any other suitable air separation technology.

[0034] In an example system as described herein, an additional reagent and / or flux unit in communication with the ferrous melt ladle (such as a hot metal ladle) may be provided. The additional reagent and / or flux unit may be used to further adjust the ferrous melt chemistry (such as hot metal chemistry). For example, the additional reagent or flux may be used to desiliconize the ferrous melt or aid in formation of liquid slag. In an example, the addition reagent and / or flux addition unit may be configured to add CaC2and / or CaO to the ferrous melt .

[0035] A slag skimmer may also be used in the system to remove slag containing SiO2from the ferrous melt with the adjusted chemistry comprising a lower Si content.

[0036] FIG. 1 shows a representation of a process for adjusting the chemical composition of a ferrous melt (such as hot metal) in accordance with an embodiment of the present disclosure. The process 100 comprises melting and reducing a pre-reduced iron oxide in an electric smelting furnace (ESF) 102; producing a ferrous melt comprising silicon 104; tapping the ferrous melt from the ESF 106; providing an oxide to the ferrous melt 108; and oxidizing the silicon in the melt with the oxide 110. In an embodiment the process 100 may comprise receiving an off-gas from the ESF 112; and obtaining CO and I or CO2from the off-gas 114; and providing the CO and / or CO2to the ferrous melt as or as part of the oxide 116.

[0037] FIG. 2 shows a representation of a system for ferrous melt chemistry adjustment. The system 200 comprises an electric smelting furnace 202, a ladle station 204, and an oxide addition unit 206. A pre-reduced iron oxide is provided to the ESF 202. The ESF melts and reduces the iron oxide into a slag and a ferrous melt. The ferrous melt comprises a first silicon content. The slag comprises SiO2. The SiO2in the slag partially reduces to Si which reports to the ferrous melt. The melt in the ESF 202 is tapped to theladle station 204. The oxide addition unit 206 provides one or more oxides to the melt in the ladle station 204. The oxide oxidizes the Si in the melt to reduce the amount of silicon in the melt. This may also be referred to herein as producing a second ferrous melt comprising a silicon content that is less than the silicon content of the first melt. In an embodiment the oxide comprises another element other than oxygen. The other element may be carbon, for example. The other element reports to the ferrous melt during oxidization to increase the content of the element in the melt. Optionally, the system may comprise an air separation unit 208. The air separation is connected to the ESF 202. In an embodiment the air separation unit 208 may be connected to another element of the metallurgical plant that produces an off-gas comprising CO or CO2. The air separation unit 208 receives off-gas from the ESF 202 or other plant element to obtain CO and / or CO2. The CO and / or CO2 may need to be extracted from the off-gas. The CO and / or CO2 is provided to the oxide addition unit 206 as an oxide for further providing to the ferrous melt in the ladle stations 204.

Claims

CLAIMS:We claim:

1. A process for an electric smelting furnace (ESF) plant, the process comprising: melting and reducing using a reductant a pre-reduced iron oxide containing silica in the ESF to produce(i) a silicon-bearing ferrous melt with a first silicon content,(ii) a slag containing SiC>2, wherein the SiC>2 in the slag partially reduces to Si and the Si reports to the ferrous melt in the ESF, and(iii) an ESF off-gas; tapping the melt with the first silicon content from the ESF; and providing to the ferrous melt with the first silicon content an oxide , the oxide configured for oxidizing the Si, and the element reporting to the ferrous melt to produce a ferrous melt with a second silicon content and an increased content of the element, wherein the second silicon content is lower than the first silicon content.

2. The process of claim 1 , wherein the ferrous melt with the first silicon content is a hot metal with a first silicon content, and the ferrous melt with the second silicon content is a hot metal with a second silicon content.

3. The process of claims 1 or 2, wherein the oxide comprises oxygen bound to another element, and wherein in response to providing the oxide to the ferrous melt with the first silicon content, the element reports to the ferrous melt to increase the content of the element in the ferrous melt.

4. The process of any one or claims 1 to 3, further comprising obtaining from the ESF off-gas the oxide for providing to the ferrous melt.

5. The process of claim 4, wherein the ESF off-gas comprises CO, and wherein the element is carbon.

6. The process of claim 5, wherein the oxide is provided to the ferrous melt with the first silicon content to cause the ferrous melt with the second silicon content to have a higher carbon content relative to the ferrous melt with the first silicon content.

7. The process of any one of claims 5 or 6, wherein providing the oxides to the ferrous melt comprises CO bubbling or CO injection into the ferrous melt.

8. The process of claim 7, wherein the CO injection is via a lance that expels an inert gas while the lance is outside of the ferrous melt, and expels the CO when the lance is lowered towards, is at a select distance from, or is immersed into the ferrous melt.

9. The process of claim 1 wherein the oxide is any one or more of O2, CO, MnO, V2O3, Cr20s, FeO, Fe2O3, and Fe3O4.

10. The process of claim any one of claims 1 to 8, wherein providing the oxide to the ferrous melt comprises bubbling or injection of the oxide into the ferrous melt.

11. The process of claim 10, wherein the injection is via a lance that expels an inert gas while the lance is outside of the hot metal and expels the oxide when the lance is lowered towards, is at a select distance from, or is immersed into the hot metal.

12. A process for adjusting ferrous melt chemistry wherein the ferrous melt comprises a first silicon content ferrous melt, the process comprising adding an oxide for oxidizing silicon to the first silicon content ferrous melt to produce a second silicon content ferrous melt, the second silicon content being less than the first silicon content.

13. The process of claim 12, wherein the process is for adjusting hot metal chemistry, and the first silicon content ferrous melt is a first silicon content hot metal, and the second silicon content ferrous melt is a second silicon content hot metal.

14. The process of claim 12 or 13, wherein the oxide comprises oxygen bound to another element, and wherein in response to adding the oxide the amount of the element increases in the second silicon content ferrous melt.

15. The process of any one of claims 12 to 14, wherein the oxide is gaseous, liquid, or solid.

16. The process of any one of claims 12 to 15, wherein adding the oxide to the first silicon content ferrous melt also produces a by-product stream comprising an oxide of silicon.

17. The process of claim 14 wherein the oxide of silicon is silicon dioxide (SiCh) or silicon monoxide (SiO).

18. The process of any one of claims 12 to 17, further comprising receiving in the first silicon content ferrous melt the oxide as a gaseous oxide from off-gas of an industrial operation.

19. The process of any one of claims 12 to 17, comprising receiving in the first silicon content ferrous melt the oxide as a gaseous oxide from off-gas of a furnace.

20. The process of claim 18 or 19, wherein the off-gas is directed to an air separation unit to extract the gaseous oxide before adding the oxide to the first silicon content ferrous melt.

21. The process of claim 18 or 19, wherein the off-gas comprising the oxide is directly received into the first silicon content ferrous melt.

22. The process of any one of claims 18 to 21 wherein the gaseous oxide is carbon monoxide.

23. The process of claim 22 wherein the second silicon content ferrous melt comprises a higher carbon content as compared to the first silicon content ferrous melt.

24. The process of claim 22 or 23, wherein adding the carbon monoxide to the ferrous melt comprises CO bubbling or CO injection into the ferrous melt.

25. The process of any one of claims 22 to 24, wherein when the ferrous melt is hot metal, the CO simultaneously carburizes and desiliconizes the hot metal.

26. The process of claim 12 wherein the oxide is any one or more of oxygen, carbon monoxide, manganese oxide, chromium oxide, vanadium oxide, and iron oxide.

27. The process of any one of claims 12 to 26, wherein adding the oxide to the first silicon content ferrous melt comprises bubbling or injection of the oxide into the first silicon content ferrous melt.

28. The process of claim 27, wherein the injection of the oxide is via a lance and comprises expelling an inert gas while the lance is outside of the ferrous melt, and expelling the oxide when the lance is lowered towards, is at a select distance from, or is immersed in the ferrous melt.

29. The process of any one of claims 12 to 28, further comprising adding additional reagents and / or fluxes to the ferrous melt to desiliconize the ferrous melt or aid in formation of liquid slag.

30. The process of claim 29, wherein the additional reagents and / or fluxes comprise CaC2 and / or CaO.

31. The process of any one of claims 12 to 30, wherein the oxide comprises a solid oxide and one or more of a gaseous oxide and an inert gas.

32. The process of claim 31, wherein the one or more of a gaseous oxide and an inert gas are configured as carrier gases for the solid oxide.

33. A system for post taphole ferrous melt chemistry adjustment, the system comprising an upstream electric smelting furnace (ESF), a ferrous melt ladle station in communication with and downstream of the ESF, and an oxide addition unit in communication or integrated with the ferrous melt ladle station.

34. The system of claim 33 wherein the ferrous melt ladle station is a torpedo car, ladle, iron pot, transfer car, or other ferrous melt collection vessel.

35. The system of claim 33 or 34 wherein the ESF comprises a tap hole that is fluidly connected to the ferrous melt ladle station.

36. The system of any one of claims 33 to 35 wherein the addition unit is integrated with the ferrous melt ladle station.

37. The system of claim 34 wherein the addition unit is a porous plug or a lance.

38. The system of any one of claims 33 to 37 wherein the addition unit is connected to an air separation unit.

39. The system of claim 38 wherein the air separation unit separates off-gases from various sources to extract carbon monoxide.

40. The system of claim 39 wherein the off-gases are from the ESF or any other furnace or industrial operation upstream or downstream of the system.

41. The system of claim 40 wherein the off-gases are from a steelmaking furnace downstream of the ESF.

42. The system of claim 38 wherein the air separation unit extracts carbon monoxide from the off-gases and the addition unit injects or bubbles carbon monoxide into the ferrous melt ladle station.

43. The system of claim 37 wherein the lance is configured to inject any one or more of manganese oxide, chromium oxide, and vanadium oxide, in combination with one or more of carbon monoxide, carbon dioxide and an inert gas.

44. The system of any one of claims 38 to 42 wherein the air separation unit is a reverse water gas shift reactor.

45. The system of any one of claims 33 to 44 further comprising an additional reagent and / or flux unit in communication with the ferrous melt ladle station.

46. The system of any one of claims 33 to 45, wherein the system is configured for hot metal chemistry adjustment, and wherein the ferrous melt is a hot metal.

47. The system of any one of claims 33 to 46, wherein the oxide addition unit is one or more of a oxygen, carbon monoxide, manganese oxide, chromium oxide, vanadium oxide, and iron oxide addition unit.

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