Claims:
1. A tuyerefacilitating reduced heat flux there-through, said tuyere comprising:
a hard facing provided on at least a first portion of outside surface of said tuyere; and
a refractory lining provided on at least a second portion of inside surface of said tuyere.

2. The tuyere of claim 1, wherein said hard facing comprises a Nickel-Chromium (Ni-Cr) alloy.

3. The tuyere of claim 1, wherein said refractory lining comprises an alumina refractory material.

4. The tuyere of claim 3, wherein said alumina refractory material comprises at least 70% alumina (Al2O3) content.

5. The tuyere of claim 1, wherein the hard facing has a thickness of around 3 mm,and wherein the refractory lining has a thickness of around 12 mm.

6. A blast furnace comprising one or more tuyeres, at least one of said one or more tuyeres comprising:
a hard facing provided on outside surface of said tuyere; and
a refractory lining configured on inside surface of said tuyere.

7. The blast furnace of claim 6, wherein said hard facing comprises a Nickel-Chromium (Ni-Cr) alloy.

8. The blast furnace of claim 6, wherein said refractory lining comprises an alumina refractory material.

9. The blast furnace of claim 8, wherein said alumina refractory material comprises at least 70% alumina (Al2O3) content.

10. A method for dispensing a fluid into a blast furnace, the method comprising the steps of:
applying a first coating over at least a portion of an external surface of a tuyere, wherein the first coating comprises Nickel-Chromium (Ni-Cr) alloy; and
applying a second coating over at least a portion of an internal surface of the tuyere, wherein the second coating is a castable coating having at least 70% alumina (Al2O3) content.
, Description:
TECHNICAL FIELD
[0001] The present disclosure relates to the field of a blast furnace, and more particularly relates to a modified tuyere that reduces heat loss in the blast furnace.

BACKGROUND OF THE INVENTION
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron, but also others such as lead or copper. Blast furnace is a counter current reactor where reduction takes place between gases and solids. The hot blast air is injected into the blast furnace through tuyere. The reducing gas flows upwards reducing the iron bearing burden materials charged at the top of the furnace.
[0004] Blast furnace uses highly pure copper water-cooled tuyeres as injection points for high velocity (blast) pre-heated air mixture to the blast furnace for oxide reduction. Thus, tuyeres are exposed to a harsh and turbulent operating environment. These tuyeres periodically fail and such failure leads to increased costs for replacing the tuyeres, lost productivity and environmental exposure.
[0005] A blast furnace coke is a key energy source or fuel. There is no other satisfactory material available that can replace, fully or partially, blast furnace coke as a fuel. Coke rate is a parameter for consumption of blast furnace coke, which can be measured in kilograms of blast furnace coke consumed per ton of hot metal produced. Coke rate can be directly related to cost of metal produced. If coke rate is increased, cost of metal also increases. To increase efficiency of blast furnace, coke rate should be maintained at an optimum level.
[0006] Heat flux has a greater influence on blast furnace operation. Optimum heat flux is required for smooth blast furnace operation. Heat flux may be calculated by formula, heat flux = V d S ? t. where V = flow rate of water, S = specific heat of the cooling medium, d = density of cooling medium & ? t = temp difference between outlet and inlet temp. In general, heat loss in blast furnace through cooling is about 5-7%; heat loss through top gas is around 2-5%. Therefore, total heat loss is around 7-10%. Of the total cooling heat loss, around 50-60% heat loss takes place in stave/plate coolers, around 25-30% heat loss takes place in tuyeres, around 10-12% in hot blast valve & around 5-7% heat loss takes place in hearth.
[0007] There is therefore a need in the art to decrease heat flux and thus consumption of coke so as to reduce effective cost of production of metal.
[0008] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[0009] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about.” Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
[0010] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0011] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[0012] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all groups used in the appended claims.

OBJECTS OF THE INVENTION
[0013] An object of the present disclosure is to provide a modified tuyere that facilitates reduction in heat loss through tuyeres.
[0014] Another object of present disclosure is to provide a modified tuyere that helps preventing erosion and abrasion, thereby decreasing rate of wearing out of the tuyere.
[0015] Another object of present disclosure is to provide a modified tuyere that enables reduction in cost of overall process of smelting.
[0016] Another object of present disclosure is to reduce interruptions in production due to failure of tuyere since replacement of a single tuyere interrupts operation of the blast furnace for around 4-5 hours.

SUMMARY
[0017] The present disclosure relates to the field of a blast furnace, and more particularly relates to a modified tuyere that reduces heat loss in the blast furnace.
[0018] In an aspect, the present disclosure relates to a tuyere configured to facilitate reduced heat flux there-through, wherein the proposed tuyere comprises a hard facing provided on at least a first portion of outside surface of said tuyere; and a refractory lining provided on at least a second portion of inside surface of said tuyere.
[0019] In an aspect, the hard facing can include a Nickel-Chromium (Ni-Cr) alloy. In another aspect, the refractory lining can include an alumina refractory material, wherein the alumina refractory material can include at least 70% alumina (Al2O3) content.
[0020] In an aspect, the hard facing can have a thickness of around 3 mm, and the refractory lining can have a thickness of around 12 mm.
[0021] The present disclosure further relates to a blast furnace comprising one or more tuyeres, at least one of said one or more tuyeres comprising: a hard facing provided on outside surface of said tuyere; and a refractory lining configured on inside surface of said tuyere.
[0022] In another aspect, the present disclosure relates to a method for dispensing a fluid into a blast furnace, the method comprising the steps of:applying a first coating over at least a portion of an external surface of a tuyere, wherein the first coating comprises Nickel-Chromium (Ni-Cr) alloy; and applying a second coating over at least a portion of an internal surface of the tuyere, wherein the second coating is a castable coating having at least 70% alumina (Al2O3) content.
[0023] The present disclosure relates to a modified tuyere to reduce heat loss. In an aspect, the present disclosure relates to a tuyere comprising a first coating applied on at least a portion of an external surface of the tuyere, wherein said first coating comprises Nickel-Chromium (Ni-Cr) alloy, and a second coating applied on at least a portion of an internal surface of the tuyere, wherein the second coating is a castable coating having at least 70% alumina (Al2O3) content, wherein application of the first coating and the second coating reduces heat loss from the tuyere.
[0024] In an aspect, the first coating has a thickness of at least 3 mm. In another aspect, the second coating has a thickness of at least 12 mm.
[0025] In an aspect, application of the first coating and the second coating reduces heat loss from the tuyere ranging from 10000 Kcal/hour to 20000 Kcal/hour.
[0026] In another aspect, the proposed tuyere can be configured to dispense fluid into a blast furnace, where due to application of the first coating and the second coating, coke rate of the blast furnace is decreased to 1 Kg/thm.
[0027] In an aspect, the present disclosure relates to a method for dispensing a fluid into a blast furnace, the method comprising the steps of, applying a first coating over at least a portion of an external surface of a tuyere, wherein the first coating comprises Nickel-Chromium (Ni-Cr) alloy; and applying a second coating over at least a portion of an internal surface of the tuyere, wherein the second coating is a castable coating having at least 70% alumina (Al2O3) content.
[0028] In another aspect, the present disclosure relates to a blast furnace configured with a plurality of tuyeres to dispense one or more fluids into the blast furnace, wherein each tuyere of the plurality of tuyeres comprises a first coating applied on at least a portion of an external surface of the tuyere, wherein the first coating comprises Nickel-Chromium (Ni-Cr) alloy and a second coating applied on at least a portion of an internal surface of the tuyere, wherein the second coating is a castable coating having at least 70% alumina (Al2O3) content, wherein application of the first coating and the second coating reduces heat loss from the tuyere.
[0029] Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

BRIEF DESCRIPTION OF THE DRAWINGS
[0030] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.
[0031] FIG. 1 illustrates an exemplary representation of the proposed tuyere in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION
[0032] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0033] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.
[0034] Various terms as used herein are shown below. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.
[0035] The present disclosure relates to the field of a blast furnace, and more particularly relates to a modified tuyere that reduces heat loss in the blast furnace.
[0036] In an aspect, the present disclosure relates to a tuyere configured to facilitate reduced heat flux there-through, wherein the proposed tuyere comprises a hard facing provided on at least a first portion of outside surface of said tuyere; and a refractory lining provided on at least a second portion of inside surface of said tuyere.
[0037] In an aspect, the hard facing can include a Nickel-Chromium (Ni-Cr) alloy. In another aspect, the refractory lining can include an alumina refractory material, wherein the alumina refractory material can include at least 70% alumina (Al2O3) content.
[0038] In an aspect, the hard facing can have a thickness of around 3 mm,and the refractory lining can have a thickness of around 12 mm.
[0039] The present disclosure further relates to a blast furnace comprising one or more tuyeres, at least one of said one or more tuyeres comprising: a hard facing provided on outside surface of said tuyere; and a refractory lining configured on inside surface of said tuyere.
[0040] In another aspect, the present disclosure relates to a method for dispensing a fluid into a blast furnace, the method comprising the steps of:applying a first coating over at least a portion of an external surface of a tuyere, wherein the first coating comprises Nickel-Chromium (Ni-Cr) alloy; and applying a second coating over at least a portion of an internal surface of the tuyere, wherein the second coating is a castable coating having at least 70% alumina (Al2O3) content.
[0041] The present disclosure relates to a modified tuyere to reduce heat loss. In an aspect, the present disclosure relates to a tuyere comprising a first coating applied on at least a portion of an external surface of the tuyere, wherein said first coating comprises Nickel-Chromium (Ni-Cr) alloy, and a second coating applied on at least a portion of an internal surface of the tuyere, wherein the second coating is a castable coating having at least 70% alumina (Al2O3) content, wherein application of the first coating and the second coating reduces heat loss from the tuyere.
[0042] In an aspect, the first coating has a thickness of around 3 mm. In another aspect, the second coating has a thickness of around 12 mm.
[0043] In an aspect, application of the first coating and the second coating reduces heat loss from the tuyere ranging from 10000 Kcal/hour to 20000 Kcal/hour.
[0044] In another aspect, the proposed tuyere can be configured to dispense fluid into a blast furnace, where due to application of the first coating and the second coating, coke rate of the blast furnace is decreased to 1 Kg/thm.
[0045] In an aspect, the present disclosure relates to a method for dispensing a fluid into a blast furnace, the method comprising the steps of, applying a first coating over at least a portion of an external surface of a tuyere, wherein the first coating comprises Nickel-Chromium (Ni-Cr) alloy; and applying a second coating over at least a portion of an internal surface of the tuyere, wherein the second coating is a castable coating having at least 70% alumina (Al2O3) content.
[0046] In another aspect, the present disclosure relates to a blast furnace configured with a plurality of tuyeres to dispense one or more fluids into the blast furnace, wherein each tuyere of the plurality of tuyeres comprises a first coating applied on at least a portion of an external surface of the tuyere, wherein the first coating comprises Nickel-Chromium (Ni-Cr) alloy and a second coating applied on at least a portion of an internal surface of the tuyere, wherein the second coating is a castable coating having at least 70% alumina (Al2O3) content, wherein application of the first coating and the second coating reduces heat loss from the tuyere.
[0047] FIG. 1 illustrates an exemplary representation of the proposed tuyerein accordance with an embodiment of the present disclosure.
[0048] In an exemplary implementation, length of the proposed tuyere 100 can be 600 mm and its inner diameter can be 140 mm, which, as would be appreciated, is completely exemplary and any other dimension is well within the scope of the present invention. Cooling arrangement of the proposed tuyere can be open loop, wherein rate of flow of water in inlet130 can be 7-10 m3 per hour at a pressure of 6 kg/cm2, wherein temperature T1 can be representative of inlet temperature. Water outlet 140 can be used for discharge of water or coolant, wherein temperature T2 can be representative of outlet temperature, and delta T is (outlet temperature T2 – inlet temperature T1) through the tuyere.
[0049] In an exemplary implementation, coal dust injection facility can be available through the proposed tuyere 100.
[0050] In an embodiment, the proposed tuyere100 can be configured to facilitate reduced heat flux there-through, wherein the proposed tuyere100 can include a hard facing 110 provided on at least a first portion of outside surface of said tuyere; and a refractory lining 120 provided on at least a second portion of inside surface of said tuyere. In an aspect, the hard facing 110 (also interchangeably referred to as first coating 110 hereinafter)can be applied on an external surface of the tuyere 100, wherein the first coating 110 can use nickel-chromium (Ni-Cr) alloy as the material of construction. In an embodiment, the first coating 110 can have a thickness of around 3 mm, and can be applied to at least 100 mm length of surface area from tip of tuyere, starting at outlet of hot air blast.
[0051] In an embodiment, refractory lining 120 (also interchangeably referred to as second coating 120 hereinafter) can be applied on an internal surface of the tuyere 100, wherein the second coating 120 can be made of castable coating having at least 70% alumina (Al2O3) content as its respective material of construction. In an exemplary implementation, the second coating 120 can have a thickness of around 12 mm, and can be applied to a portion of internal surface.
[0052] In an aspect, the first hard facing coating 110 and the second refractory coating 120 can be applied on at least a portion of external and internal surface respectively,thereby assisting in reduction of heat flux, and can assist in prevention of erosion and abrasion, thereby decreasing rate of wearing out of the tuyere 100.
[0053] In an aspect, on application of the first hard facing coating 110 and the second refractory coating 120, it is possible to decrease 1-2oC of delta T in tuyere 100, which can decrease heat loss through tuyereto 10-20 %, and also reduce heat flux from each tuyere100 ranging from 10000-20000 Kcal/hour. Also, on application of the first hard facing coating 110 and the second refractory coating 120 in blast furnace, coke ratecan be decreased to around 1 Kg/thm.
[0054] It is to be appreciated that although exemplary illustrations show only one tuyere integrated in blast furnace, it is possible to integrate more than one tuyere in blast furnace using the disclosed concept.
[0055] It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refers to at least one of something selected from the group consisting of A, B, C ….and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc. The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the appended claims.
[0056] While embodiments of the present disclosure have been illustrated and described, it will be clear that the disclosure is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the disclosure, as described in the claims.

ADVANTAGES OF THE INVENTION
[0057] The present disclosure provides a modified tuyere that facilitates reduction in heat loss at tuyere.
[0058] The present disclosure provides a modified tuyere, preventing its erosion and abrasion, thereby decreasing rate of wearing out of tuyere.
[0059] The present disclosure provides a modified tuyere that enables reduction in cost of overall process of smelting.
[0060] The present disclosure provides a modified tuyere to reduce interruptions in production due to failure of tuyere. Since replacement of single tuyere interrupts the operation of the furnace for 4-5 hours.