Cooling systems and method of using the same

Abstract

Systems and methods of cooling a wall of a refractory are provided herein. The system comprises at least one plate positioned at a plate angle measured from a plane parallel to an exterior surface of the wall of the refractory, the plate angle being a non-zero angle. The system further comprises at least one gas source configured to direct a gas between the at least one plate and the exterior surface of the wall of the refractory. The gas is expelled so as to maintain a laminar flow along the exterior surface of the wall of the refractory, thereby cooling the exterior surface.

Description

COOLING SYSTEMS AND METHOD OF USING THE SAMECROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Application Serial No. 63 / 561855 filed on March 6, 2024, the content of which is relied upon and incorporated herein by reference in its entirety.FIELD

[0002] Embodiments discussed herein relate generally to cooling systems, and more particularly, to modular cooling systems which may be independently installed to provide cooling to a surface, such as a surface of the refractory, thereby decreasing the surface temperature and rate of corrosion thereof.BACKGROUND

[0003] Refractories and similar tanks which hold and utilize large quantities of hot material wear down over time. For example, glass contact refractories, which hold molten glass, may operate at temperatures between 1400 - 1600°C. Although refractories are designed to operate at high temperatures over time, the molten glass may corrode and wear down the refractory material due to chemical reactions between the glass and refractory material at elevated temperatures. Notably, the corrosion of the refractory material causes the thickness of the refractory wall to decrease, which may lead to failures and inefficiencies in the overall process.

[0004] In order for the refractory to be operable, the refractory wall must be at a safe thickness and should not affect the quality of the glass produced therein. Once the refractory wall thickness is below a threshold thickness, due to corrosion, it is no longer possible to (i) form glass of adequate quality due to impurities (e.g., zirconia stones), and / or (ii) it is no longer safe to continue the tank operations. At this point the tank is shut down and the refractory wall must be rebuilt which takes between 6-8 weeks to complete - causing increased maintenance cost and lost glass production. Thus, there exists a need to slow the corrosion of the refractory wall thereby extending the life span of the tank and / or refractory.BRIEF SUMMARY

[0005] Embodiments of the present disclosure are directed towards cooling systems and methods that can be used, for example, with cooling refractories, thereby extending the life span. The cooling system is a modular system, independent of a refractory, which may be installed and removed at any time throughout the life span of the refractory. The system is configured to cool a surface of the refractory to reduce the corrosion caused by the reaction between the wall and glass within the refractory, and thereby extend the life span of the refractory (e.g., a tank within the refractory). Since the system is modular it may be installed at any time through the life span of the tank. In this regard, the system may be installed when cooling is beneficial, for example, once the refractory wall reaches a threshold temperature indicating a corrosion rate which may be reduced with the reduction of the temperature.

[0006] The system for cooling the surface of a refractory wall comprises at least one plate positioned relative to the surface of the wall. The at least one plate may be angled so as to create a non-zero angle, when measured from a plane parallel to the surface of the refractory wall. At least one gas source may be positioned below the at least one plate to direct gas between the at least one plate and the wall. The gas may be expelled such that the gas maintains a laminar flow between the base of the refractory wall and the top of the refractory wall, thereby cooling the entire height of the refractory wall.

[0007] In some embodiments, the system may comprise multiple plates, and / or multiple gas sources to increase cooling along the height of the wall. The positions and angles of the plate may direct cooling to specific locations along the wall, while maintaining cooling along the entire height.

[0008] In an example embodiment a system for cooling a wall of a refractory surrounding a tank is provided. The system is positioned adjacent an exterior surface of the wall. The system comprises at least one plate positioned at a plate angle. The plate angle is measured from a plane parallel to the exterior surface of the wall and is a non-zero angle. The system further comprises at least one gas source configured to direct a gas between the at least one plate and the exterior surface of the wall of the refractory. The gas maintains a laminar flow along the exterior surface of the wall of the refractory to provide colling for the wall of the refractory.

[0009] In some embodiments, the at least one plate may be formed of carbon steel. In some embodiments, the at least one plate may comprise a high emissivity coating. In some embodiments, the at least one plate may define a first edge and a second edge. The first edge may be opposite the second edge, the first edge being positioned closer to the exterior surfaceof the wall of the refractory than the second edge. In some embodiments, the first edge may be curved away from the exterior surface of the wall of the refractory.

[0010] In some embodiments, the at least one plate may be a first plate and the system may further comprise a second plate. The second plate may be positioned vertically above the first plate. The second plate may be positioned at a second plate angle, wherein the second plate angle is measured from the plane parallel to the exterior surface of the wall of the refractory. The second plate angle may be a non-zero angle. In some embodiments, the second plate angle may be different than the plate angle. In some embodiments, the plate angle may be smaller than the second plate angle. In some embodiments, the second plate may define a first plate edge and a second plate edge wherein the first plate edge is positioned closer to the exterior surface of the wall of the refractory than the second plate edge. In some embodiments, the first plate edge of the second plate may be curved away from the exterior surface wall of the refectory.

[0011] In some embodiments, the at least one gas source may be a first gas source and a second gas source. The first gas source may be positioned closer to the exterior surface than the second gas source. In some embodiments, the at least one gas source may be positioned at a source angle. In some embodiments, the source angle may be between 3-20 degrees. In some embodiments, the plate angle may be between 0.5 - 20 degrees.

[0012] In another example embodiment a method of cooling a wall of a refractory surrounding a tank is provided. The method comprises positioning at least one plate adjacent an exterior surface of the wall of the refractory. The at least one plate defines a first edge and a second edge opposite the first edge. The first edge is a first distance from the exterior surface of the wall of the refractory and the second edge is a second distance from the wall of the refractory. The method further comprises positioning a gas source at a source angle that is not perpendicular to the exterior surface of the wall. The method further comprises causing the gas source to expel a gas, such that the gas is expelled at a laminar flow rate. The source angle causes the gas to contact a base of the exterior surface of the wall of the refractory, such that the gas reduces a temperature of at the exterior surface.

[0013] In some embodiments, the at least one plate may comprise a high emissivity coating. In some embodiments, the second edge of the at least one plate may be positioned closer to the gas source than the first edge. In some embodiments, the first distance may be smaller than the second distance.

[0014] In some embodiments, the method may further comprise positioning a second plate defining a first edge and a second edge above the at least one plate such that the first edge ofthe at least one plate is positioned between the second edge of the second plate and the exterior surface of the wall of the refractory. In some embodiments, the method may further comprise positioning a second gas source at a second source angle, such that the second gas source expels gas between the at least one plate and the second plate.

[0015] In some embodiments, the first edge of the at least one plate may be curved away from the refractory. In some embodiments, the source angle may be between 3-20 degrees.

[0016] In yet another example embodiment a cooling system for cooling a wall is provided. The cooling system is positioned adjacent an exterior surface of the wall. The cooling system comprises a first plate defining a first edge and a second edge opposite the first edge. The first edge is a first distance from the exterior surface and the second edge is positioned a second distance from the exterior surface. The first distance is smaller than the second distance, such that a first plate angle is defined with respect to a plane parallel to the exterior surface of the wall. The first plate angle being a non-zero angle. The cooling system further comprises a second plate defining a first edge and a second edge opposite the first edge. The first edge is a third distance from the exterior surface and the second edge is a fourth distance from the exterior surface. The third distance is smaller than the fourth distance such that a second plate angle is defined with respect to the plane parallel to the exterior surface of the wall. The second plate angle being a non-zero angle. The first edge of the first plate is positioned between the exterior surface and the second edge of the second plate. The cooling system further comprises a first gas source configured to expel a first gas so as to form a laminar flow between the first plate and the exterior surface of the wall of the refractory, and a second gas source configured to expel a second gas so as to form a laminar flow between the first plate and the second plate.

[0017] In some embodiments, each of the first plate and the second plate may comprise a high emissivity coating. In some embodiments, the first plate angle may be smaller than the second plate angle. In some embodiments, the first plate edge of the first plate may be curved away from the first exterior surface of the wall and the first plate edge of the second plate may be curved away from the exterior surface of the wall.

[0018] In some embodiments, the first gas source may be positioned at a first source angle and the second gas source may be positioned at a second source angle. The first source angle and the second source angle may not be perpendicular to the exterior surface of the wall.BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

[0019] Reference will now be made to the accompanying drawings, which are not drawn to scale, and wherein:

[0020] FIG. 1 illustrates an example spot cooling system, in accordance with some examples discussed herein;

[0021] FIG. 2 is a schematic type representation of an example refractory, in accordance with some embodiments discussed herein;

[0022] FIG. 3A illustrates an example system for cooling a surface of refractory wall, in accordance with some embodiments discussed herein;

[0023] FIG. 3B illustrates another example system for cooling a surface of a refractory wall, in accordance with some embodiments discussed herein;

[0024] FIG. 4 illustrates an example gas source, in accordance with some embodiments discussed herein;

[0025] FIGs. 5A-C illustrate an example system for cooling a surface of a refractory wall, in accordance with some embodiments discussed herein;

[0026] FIG. 6 illustrates an example system for cooling a surface of a refractory wall, in accordance with some embodiments discussed herein;

[0027] FIG. 7A illustrates an example velocity gradient utilizing the example system for cooling the surface of a refractory wall, in accordance with some embodiments discussed herein;

[0028] FIG. 7B illustrates example temperature gradients utilizing the example system for cooling the surface of a refractory wall, in accordance with some embodiments discussed herein;

[0029] FIG. 8 illustrates a chart presenting the cooling effect of various cooling systems in a lab setting, in accordance with some embodiments discussed herein; and

[0030] FIG. 9 illustrates a flow chart of an example method of cooling a surface of a refractory wall, in accordance with some embodiments discussed herein.DETAILED DESCRIPTION

[0031] Some example embodiments will not be described more fully herein with reference to the accompanying drawings, in which some, but not all example embodiments are shown. Indeed, the examples described and pictured herein should not be construed as being limiting to the scope, applicability or configuration of the present disclosure. Rather, these exampleembodiments are provided so that this disclosure will satisfy applicable legal requirements. Like reference numerals refer to like elements throughout.

[0032] Directional terms as used herein- for example, up, down, left, right, front, back, top, bottom, vertical, and horizontal - are made with reference to the figures as drawn and are not intended to imply absolute orientation.

[0033] Glass contact refractories may wear down over time and more specifically may be corroded and worn down due to the molten glass contained within. A chemical reaction occurs between the glass and compounds of the refractory, for example, dissolution reactions. Many of the reactions may accelerate at elevated temperatures, which results in thinning of the refractory wall. Corrosion at this magnitude creates two main issues within the refractory, first the refractory wall thins, such that the wall is no longer safe to maintain the contents.Second, due to the reaction, the glass being produced may contain zirconia stones, which may be traced back to the corrosion of the refractory wall. Such example additional material may render the product unsatisfactory or unusable. At this point, manufacturing operations utilizing the refractory are shut down, and a rebuild process begins, which may take between 6-8 weeks to complete - costing extra maintenance fees and lost glass production.

[0034] Maintaining or cooling the temperature of the refractory wall may slow down the reactions between the glass and the refractory wall. For example, dissolution reactions are one of the main causes of corrosion of the refractory wall. Dissolution reactions generally follow an Arrhenius rate equation, of: k = Ae(RT}where k is the rate of the reaction, A is frequency factor, EA is activation energy, R is the gas constant, and T is the temperature. Thus, the temperature effects the corrosion rate in a nonlinear manner. Therefore, due to the non-linear relationship between the temperature and the corrosion rate, a reduction in temperature of the refractory wall by 10-50 °C (e g., 1%) may reduce the corrosion rate by 50% or more.

[0035] Thus, maintaining the temperature, and corrosion rate at the refractory wall reduces thinning of the refractory wall, and reduces the amount of zirconia stones in the glass product. Maintaining and reducing the temperature and corrosion rate may extend the life span of the tank by a few months, or even over a year which provide a monetary benefit of savings of extended life of operation, reduced maintenance costs for building a new tank, and continued glass production.

[0036] Spot cooling refractory walls may locally reduce the temperature of the wall in specific and localized areas. A spot cooling system 10, is illustrated in FIG. 1. The spot cooling system 10 may utilize a fan 20 to direct air 25 at a refractory wall 15 The refractory wall 15 may define a height H, the entirety of which may be exposed to high temperatures from the molten glass and operations within the tank. However, the air 25 from the fan 20 may only cool a cooling height He of the refractory wall 15, as the air 25 is only contacts the cooling height He. In this regard, only a portion of the refractory wall 15 is cooled, therefore, the corrosion rate is only decreased in a localized area.

[0037] Other methods of spot cooling may utilize mist to decrease the temperature in a localized area of the refractory wall. However, the methods of spot cooling do not uniformly decrease the temperature across the width or height of the refractory wall, and may be hard to control to direct the cooling into a desired location. Further, these methods may be used for urgent or quick fixes to avoid a disaster, but may not be employed long term, as they are not efficient, due to the rapid decay in cooling properties as the distance from the cooled spot increases as only a small portion of the refractory wall is receiving the air.

[0038] Other methods of cooling may be installed at the same time as refractory installation. However, these systems take up space, and energy, as they are implemented throughout the life span of the refractory rather than, when necessary, as cooling the refractory wall may not be efficient when first installed due to the thickness of the refractory wall.

[0039] Some of these cooling systems may require intimate contact between the cooling system and the refractory brick to be effective, Thus, any changes in contact area, for example due to air gaps, corrosions, or bricks shifting may result in inefficient or a lack of cooling.

[0040] Efficient uniform cooling may be provided by the present system and may be installed when the refractory wall reaches a thickness where cooling may be effective. In this regard, the temperature of the refractory wall may be measured, such as using an infrared gun, to determine the thickness of the refractory wall. Once the temperature and thickness reach a level which may benefit from cooling (e.g., to slow the corrosion) the system may be installed.

[0041] FIG. 2 illustrates an example tank refractory 105 which may be cooled by a cooling system. In some embodiments, the refractory 105 may comprise a plurality of refractory walls 115 surrounding an internal tank 107 which may hold molten glass, and other high temperature compositions. In some embodiments, the refractory wall 115 may define a wall thickness Tw which may decrease over the life span of the tank refractory 105 due tocorrosion. In some embodiments, grating 113 may be positioned on the refractory wall 115, to dissipate heat from the refractory wall 115.

[0042] In some embodiments, the system of the present disclosure may be installed at any time when the refractory wall reaches a temperature and / or a thickness Tw which may indicate a benefit from cooling. As discussed above, the refractory wall may be installed with a thickness of about 8 in. The thickness of the wall decreases due to the corrosion reaction between the glass and the refractory brick. When the refractory wall is initially installed, providing cooling to the wall may not provide benefits as, the wall thickness is too great for the cooling to have a significant impact on the hot face temperature. (The thermal energy exchanged through a wall is directly related to the thickness of said wall.) e. However, as the refractory ages, the thickness decreases due to the corrosion, which is directly related to the temperature of the refractory wall. Thus, when the temperature of the refractory wall indicates a thickness which would benefit from cooling, the systems of the present disclosure may be installed to begin cooling of the refractory wall, thereby slowing the corrosion reaction.

[0043] FIGs. 3A-B illustrate example configurations of a system 100 for cooling the refractory wall 115. In some embodiments, such as illustrated in FIG. 3A, the refractory wall 115 may have an exterior surface 115a and an interior surface 115b. The interior surface 115b may be in contact with the interior of the tank 107 and therefore may be the glass contact surface of the refractory. In some embodiments, at installation the refractory wall 115 may define a wall thickness Tw which decreases over the life span of the refractory due to corrosion.

[0044] To extend the life span of the refractory it may be beneficial to provide cooling to the exterior surface 115a of the refractory wall 115 uniformly along a height He of the refractory wall 115. In this regard, the cooling may prevent corrosion such that the refractory wall 115 maintains a safe wall thickness Tw to increase the life span of the refractory and produce products without defects. To cool uniformly along the entire refractory height He, a cooling system may be implemented.

[0045] In some embodiments, such as illustrated in FIG. 3A, a gas source 120 may be positioned at the base of the refractory wall 115 and may expel a gas 125 parallel to the refractory wall 115. In some embodiments, the gas may be air, nitrogen, carbon dioxide, or similar. In some embodiments, the gas 125 may be at ambient temperature, while in other embodiments, the gas may be below or above ambient temperature. In some embodiments, the temperature of the gas 125 may be lower than the temperature of the exterior surface 115aof the refractory wall 115. In some embodiments, the gas 125 may be a compressed gas. In some embodiments, the pressure of the gas 125 expelled from the gas source 120 may be changed to control the extent of the cooling along the refractory height He. The gas 125 supplied by the gas source 120 may cool the refractory wall 115 though convection, where the gas source 120 supplies cool gas 125 to the refractory wall 115 and the refractory wall expels heat 127 through radiative heat transfer.

[0046] In some embodiments, at least one plate 130 may be positioned a distance Dp away from the exterior surface 115a of the refractory wall 115. The at least one plate 130 may be positioned such as to create a wind tunnel between the at least one plate 130 and the refractory wall. The wind tunnel may force the gas 125 to travel up the exterior surface 115a of the refractory wall increasing the air flow. The increased air flow may increase the efficiency of the convection cooling effect created by the expelled gas 125. In some embodiments, the at least one plate may the absorb heat 127 emitted from the exterior surface 115a of the refractory wall 115. In some embodiments, the absorption may be due to radiative heat transfer.

[0047] In some embodiments, the at least one plate 130 may be a radiation plate. In this regard the at least one plate 130 may have a high thermal conductivity and a high emissivity. The combination of a high emissivity and a high thermal conductivity allows the at least one plate to absorb the heat emitted from the refractory wall, rather than reflecting the heat back towards the refractory wall. In some embodiments, the at least one plate 130 may be a ceramic material which has both a high thermal conductivity and a high emissivity, or the at least one plate 130 may be a material which may be manipulated or altered to achieve the desired properties, as these materials may be lighter, easier to source, and easier to machine than a ceramic or similarly naturally occurring material. For example, the at least one plate 130 may be a metal plate which has a high thermal conductivity and may be coated with a high emissivity coating. In some embodiments, the at least one plate may have an emissivity of greater than 0.7, greater than 0.8, or even greater than 0.85 to ensure maximum heat absorbance.

[0048] In some embodiments, the at least one plate 130 may define a plate height Hp. In some embodiments, the at least one plate 130 may be sized such that the plate height Hp is at least the size of the refractory height He. In this regard, the at least one plate 130 may create the wind tunnel effect along the entire refractory height He, while removing heat 127 along the exterior surface 115a of the refractory wall 115, which improves cooling efficiency. Additionally, the at least one plate 130 may span the width of the refractory wall 115, forexample, if the refractory wall 115 is 20 inches wide, the at least one plate 130 may be at least 20 inches wide. Thus, the heat 127 emitted from the exterior surface 115a is absorbed by the at least one plate 130.

[0049] The system 100 may provide uniform cooling along the exterior surface 115a of the refractory wall 115 as the expelled gas 125 may contact the entire exterior surface 115a along the refractory height He, rather than only engaging with a single spot. In order to cool the entire exterior surface 115a of the refractory wall 115 it may be desirable for the gas 125 to reach the top of the refractory wall 115 and to maintain contact with the exterior surface 115a along the entire refractory height He. In some embodiments, as the height increases, the gas source 120 may not be able to expel the gas 125 such that the gas 125 maintains a desirable air flow at the top of the refractory wall 115.

[0050] In some embodiments, the gas source 120 may expel the gas 125 with laminar flow. Laminar flow may be beneficial, as the gas 125 may travel in smooth paths, in multiple layers, where each layer flows adjacent to and / or past the other layer with little to no mixing. Thus, the gas 125 may travel along the external surface 115a of the wall, providing cooling along the entire flow path of the gas 125.

[0051] In some embodiments, such as illustrated in FIG. 3B, the gas source 120 may be positioned at a source angle as. The source angle as may be measured from a plane that is perpendicular to the exterior surface 115a of the refractory wall 115. Positioning the gas source 120 at the source angle as may increase the air flow at the top of the refractory wall 115 thereby extending the cooling along the entire height He of the refractory wall 115. In some embodiments, the source angle as may be between 3-20 degrees, preferably between 5- 15 degrees, and even more preferable between 7-13 degrees.

[0052] FIG. 4 illustrates the gas source 120. The gas source 120 may include a housing 121 which intakes a gas and expels the gas at a pressure and flow rate to create the laminar flow. The housing 121 may be open on one side to receive an inlet gas 123 and may include an opening 122 at the top of the housing 121 to expel the gas 125. In some embodiments, the housing 121 may be shaped such that the inlet gas 123 may be introduced into the housing121 at a flow rate causing the inlet gas to circulate 124 within the housing 121. The opening122 may be sized to expel the gas 125 in a uniform plane. Accordingly, the gas 125 may have a laminar flow such that that gas flows adjacent the external surface 115a of the refractory wall 115 and cools the entire height thereof. In some embodiments, the gas source 120 may be an air knife.

[0053] As discussed above, in some embodiments the gas 125 may be air, nitrogen, carbon dioxide, or similar. In some embodiments, the gas 125 may be at ambient temperature, while in other embodiments, the gas may be below or above ambient temperature, providing the temperature of the gas 125 is below the temperature of the exterior surface of the refractory wall. In some embodiments, the inlet gas 123 may be a compressed gas.

[0054] Airflow from the gas source, and contact area between the gas and the external surface of the refractory wall have the greatest effect on cooling. In some embodiments, it may be beneficial to angle the at least one plate to further direct the gas towards the external surface of the refractory wall. Additionally, although one plate may provide adequate cooling along the refractory wall, additional plates may be used ensure maintenance of laminar flow between the gas source and the top of the refractory wall and to introduce additional gas streams to induce greater and / or more uniform cooling. Although described herein as having two plates, it should be understood that any number of plates may be used, for example more than two plates, more than 3 plates, or even more than four plates. FIGs. 5A-C illustrate an example system 200 that utilizes more than one plate to remove heat from the refractory wall.

[0055] In some embodiments, such as illustrated, in FIG. 5A the system 200 may comprise a first plate 231 and a second plate 232. Each of the first plate 231 and the second plate 232 may be spaced apart from an exterior surface 215a of a refractory wall 215. As discussed, an internal surface 215b of the refractory wall 215 may be adjacent an internal tank 207 which holds molten glass.

[0056] In some embodiments, each of the first plate 231 and the second plate 232 may be angled with respect to the refractory wall 215 (e.g., at a non-zero angle with respect to the wall). To explain, the first plate 231 may define a first edge 231a and a second edge 23 lb, wherein the second edge 23 lb is opposite the first edge 231a. Similarly, the second plate 232 may define a first edge 232a and a second edge 232b, wherein the second edge 232b is opposite the first edge 232a. Each of the first edge 23 la of the first plate 231 and the first edge 232a of the second plate 232 may be positioned closer to the refractory wall 215 than the second edge 23 lb of the first plate 231 and the second edge 232b of the second plate 232, respectively. Thus, the first plate 231 may define a first plate angle on which is defined between a plane parallel to the refractory wall 215, wherein the first edge 23 la of the first plate 231 is the vertex of the first plate angle ai. Similarly, the second plate 232 may define a second plate angle 012 with a plane parallel to the refractory wall 215, wherein the first edge 232a of the second plate 232 is the vertex of the second plate angle 012.

[0057] In some embodiments, the first plate angle ai and the second plate angle U2 may be the same, while in other embodiments the first plate angle ai and the second plate angle 0.2 may be different. In some embodiments, the first plate angle ai may be larger than the second plate angle 012, while in other embodiments the first plate angle ai may be smaller the second plate angle az. In some embodiments, each of the first plate angle ai and the second plate angle 0.2 may be between 0.5 - 20 degrees. In some embodiments, each of the first plate angle ai and the second plate angle 012 may be adjusted throughout the use of the system. In this regard, each of the first plate angle on and the second plate angle 02 may be adjusted to direct the gas towards the exterior surface of the refractory wall 215 as necessary.

[0058] In some embodiments, positioning the first plate 231 and the second plate 232 at the first plate angle on and the second plate angle az may cause Venturi cooling. Venturi cooling happens through a reduction in fluid pressure which results from a moving fluid increasing in velocity as the fluid flows through a constricted section. In this regard, the angled plates cause a constricted section at the first edge 23 la of the first plate and the first edge 232a of the second plate 232. The constriction creates a low pressure opening causing the gas to be drawn in from the gas source 120 and expelled from the opening, thereby providing a continuous introduction of cool gas.

[0059] In some embodiments, the system 200 may comprise a first gas source 220a and a second gas source 220b. The first gas source 220a may direct gas between the first plate 231 and the refractory wall 215, while the second gas source 220b may direct gas between the first plate 231 and the second plate 232. In some embodiments, each of the first gas source 220 and the second gas source 220b may be configured as the gas source discussed with reference to FIG. 4. In some embodiments, as discussed with reference to FIG. 3B each of the first gas source 220a and the second gas source 220b may be positioned at an angle. In some embodiments, the first gas source 220a may be positioned at a first source angle asi and the second gas source 220b may be positioned at a second source angle ots2. Each of the first source angle asiand the second source angle as2 may be measured from a plane that is perpendicular to the exterior surface 215a of the refractory wall 215. In some embodiments, by angling the gas sources 220a, 220b the gas flow may be increased along the refractory wall 215 thereby improving the cooling there along.

[0060] In some embodiments, the first source angle asi and the second source angle s2 may be the same, while in other embodiments the first source angle asi and the second source angle as2 may be different. In some embodiments, the first source angle asi may be largerthan the second source angle as2, while in other embodiments the first source angle asi may be smaller the second source angle as2.

[0061] In some embodiments, the use of the first gas source 220a and the second gas source 220b may introduce gas streams at different points along the refractory wall 215 such that the cooling may be consistent along the exterior surface 215a of the refractory wall 215. To ensure a laminar flow where the multiple gas streams meet the plate angles, and the source angles may correspond. In this regard, the first source angle asi may correspond to the first plate angle ai, and the second source angle as2 may correspond to the second plate angle a?, as it may be desirable for the gas source 220a, 220b to expel gas parallel to the respective plate. Thus, the gas may travel along the respective plate and the refractory wall without cause the gas to transition into turbulent flow or an otherwise irregular flow pattern.

[0062] Returning to the configuration of the first plate 231 and the second plate 232, with reference to FIG. 5B, the first plate 231 may define a first height Hi and a first length Li and the second plate 232 may define a second height H2 and a second length L2. In some embodiments, first plate 231 and the second plate 232 may span the entire refractory height He. In this regard, the sum of the first height Hi and the second height H2 may be greater than the cooling height He to account for the first plate angle on and the second plate angle 0.2. In other embodiments the first heigh Hi and the second height H2 may not span the entire refractory height He as the first plate 231 may be spaced above the bottom of the refractory wall 215.

[0063] In some embodiments, the first length Li and the second length L2 may be the same size as a refractory length LR. In this regard, the first plate 231 and the second plate 232 may absorb heat from the entire refractory length LR. Further, the consistency between the first length Li and the second length L2 may allow the wind tunnel to be constant along the height of the refractory wall 215.

[0064] In some embodiments, the first plate 231 and the second plate 232 may define different spacing from the refractory wall, such as illustrated in FIG. 5C. In some embodiments, the first edge 23 la of the first plate 231 may be a first distance di from the exterior surface 215a of the refractory wall, and the second edges 23 lb of the first plate 231 may be a second distance d2 from the exterior surface 215a of the refractory wall 215. As discussed, the second distance d2 may be greater than the first distance di thereby creating the first plate angle cu with respect to a plane parallel to the exterior surface 215a of the refractory wall 215.

[0065] Similarly, the first edge 232a of the second plate 232 may be positioned a third distance ds away from the exterior surface 215a of the refractory wall 215, and the second edge 232b of the refractory wall may be a fourth distance d4 away from the exterior surface 215a of the refractory wall 215. In some embodiments, the third distance da may be smaller than the fourth distance d4.

[0066] In some embodiments, the first distance di and the third distance da may be the same, while in other embodiments the first distance di may be smaller than or larger than the third distance da. In this regard, the positioning of the first plate 231 and the second plate 232 may direct and constrain air flow along the refractory wall 215 to enhance the Venturi cooling effect at the first edge of each of the plates.

[0067] In some embodiments, a curved plate may increase the pressure differential of the flow. FIG. 6 illustrates an example system 300 where each of a first plate 331 and a second plate 332 have a curved edge. In some embodiments, the first plate 331 may define a first edge 331a and a second edge 331b opposite the first edge 331a, similarly the second plate 332 may define a first edge 332a and a second edge 332b opposite the first edge 331a. In some embodiments, each of the first edge 33 la of the first plate 331 and the first edge 332a of the second plate 332 may be curved. In some embodiments, the curved edge may direct the respective plate away from the refractory wall 315. In this regard, the first edge 33 la of the first plate 331 may be a first distance di from the refractory wall 315 at a closest point, and curve away from the refractory wall 315 such that the tip of the edge is a first curve distance dia away from the refractory wall 315. Similarly, the second curved edge 332a may be positioned a third distance ds away from the refractory wall 315 and curve such that the tip of the edge is a second curve distance dsafrom the refractory wall 315.

[0068] The curved edges may induce a steeper pressure gradient at the first edges 331a, 332a. Thus, the low pressure at the bottom (e.g., the second edge 331b, 332b) draws the gas up through the gap between the first plate 331 and the refractory wall 315, and between the first plate 331 and the second plate 332 towards the refractory wall 315. Further, the low pressure at the bottom may draw more gas up between the first plate 331 and the refractory wall 315 and between the first plate 331 and the second plate 332.

[0069] FIG. 7A illustrates a velocity profile 401 modeled based on the systems described herein. The velocity profile 401 illustrates the change in the velocity of the gas expelled from a gas source between a first plate 431 and a refractory wall 415, and a second plate 432 and the first plate 431. As illustrated the gas increases in velocity as it travels along the refractory wall 415, with the lowest velocity being on the side of the first plate 431 opposite therefractory wall 415, this is due to the lack of gas source directing gas at this portion of the first plate 431. As consistent with Venturi cooling, as the gas reaches a constriction point (e.g., between the first edge of the first plate and the refractory wall and between the first edge of the second plate and the refractory wall) the velocity is at a maximum. Thus, illustrating the pressure differential drawing the gas from the gas source up through the openings between the first plate 431 and the refractory wall 415 and between the second plate 432 and the refractory wall 415.

[0070] FIG. 7B illustrates a temperature profile 402 for the gas expelled by the gas source between the first plate 431 and the refractory wall 415 and between the first plate 431 and the second plate 432. As the gas causes convection cooling of the refractory wall 415 the gas heats up along the height of the refractory wall 415. However, in heating up, the gas is drawing heat away from the refractory wall and may result in the refractory wall being about 50° cooler than a single plate, and about 100-150° cooler than no plate being used. Thus, the additional plates, and specifically that angled plates draw more heat away from the refractory wall, thereby decreasing the corrosion of the refractory wall, and extending the life thereof.Examples

[0071] The effectiveness of the at least one plate positioned parallel to the refractory wall was tested in a lab. The lab developed a scale model of a refractory and tested the efficiency of different plate configurations and different plate coating to determine how to best remove heat from the refractory wall.

[0072] In order to simulate a refractory, a 1 -inch-thick piece of Fused Zirconia (FZ) was attached to a furnace held at a set temperature representative of what is seen in production, the furnace was positioned on an interior side (e.g., hot face) of the FZ, while the exterior surface was exposed to ambient conditions thereby creating a thermal gradient through the FZ. A steel grate was attached to the exterior surface (e.g., cold face) of the FZ to simulate the grating on refractory walls. The gas source was an air knife, positioned below the grating. Two air knifes were positioned 1 inch apart. The air knifes were attached to a compressed air line to provide varying pressures to the system, to evaluate the effect of air flow on cooling. The experiment tested the cooling effects of an uncoated plate, a coated plate, and no plate to determine the effect of the plate on cooling.

[0073] The lab testing evaluated the effect of changing the distance of the radiation plate from the cold face, the psi of the air coming into the air knives, and the coating of the plate with the temperature of the FZ refractory surface. The air flow was measured with ananemometer at room temperature before heating the furnace up. The airflow is a function of both the distance of the radiation plate to the external surface of the FZ and the pressure of the incoming air. The radiation plate created a wind tunnel which increased flow near the FZ. This wind tunnel effect increased as the plate was moved closer to the exterior surface of the FZ until the point where the plate cut off one of the gas sources, and as a result there was flow from just one air knife hiting the external surface of the FZ (~1” from cold face). It was shown that a greater pressure of the incoming compressed air increases the flow of the gas exiting the air knife opening.To determine the effect of the type of plate, and air flow on the temperature reduction, the pressure from the air knife was constant, while the distance from the external surface of the FZ was altered, thereby causing the air flow to change. FIG. 8 shows a chart 600 illustrating the results.

[0074] The chart 600 illustrates a plot of the temperature of internal surface (e.g., adjacent the furnace) v. air flow between the external surface of the FZ and the plate, for an uncoated plate 602, a coated plate 604, and parallel flow 606 (e.g., no plate). The hot face temperature was chosen as the response variable in testing as the hot face is where the life limiting corrosion reactions occur in production. The coated plate was a carbon steel radiation plate coated with a high emissivity coating, and the uncoated plate was an uncoated carbon steel radiation plate. For the test with no plate, an air knife directed air at a source angle of 10° such that the air hit the base of the exterior surface of the FZ and traveled up the exterior surface.

[0075] The chart 600 illustrates the effect of a high emissivity coating, as the cooling of the interior surface is far greater than when no plate, or an uncoated plate was used. At each testing flow (other than no flow) the coated plate 604 reduced the interior surface temperature by about 40°C as compared to parallel flow 606, and about 70°C as compared to the uncoated plate 602.

[0076] As illustrated, maximum cooling was achieved with a coated plate at maximum airflow 660 standard cubic feet per minute, which was achieved with an gas pressure of 90 psi, and with the plate positioned 4 inches from the external surface of the FZ. The temperature of the interface of the 1” brick was cooled ~150°C. As discussed above since the corrosion rate is related to the temperature, a 150°C reduction in the hot face temperature will result in a substantial reduction in the corrosion rate (order of magnitude).Example Flowcharts')

[0077] FIG. 8 is a flow chart illustrating an example method 500 for reducing a corrosion rate of a refractory wall in accordance with some embodiments discussed herein. Optionally, at operation 502 a temperature of a surface is taken. The temperature of the surface may indicate a current rate of corrosion and may further indicate the thickness of the refractory wall. Once the temperature of the surface indicates a threshold temperature cooling may be introduced to the surface. At operation 504, at least one plate may be positioned adjacent the surface. In some embodiments, the at least one plate may have a high thermal conductivity and high emissivity. Further, the at least one plate may be positioned at an angle relative to the surface. At operation 506, at least one gas source may be positioned below the at least one plate. At operation 508, a flow of gas may be directed between the between the at least one plate and the surface, to induce cooling of the surface. In some embodiments, the number of gas sources may be the same as the number of plates, while in other embodiments the number of gas sources may be greater than the number of plates.

[0078] Notably, the above operations for FIG. 8, while described in a certain order, may be performed in a different order and / or some of the operations may be performed simultaneously.Conclusion

[0079] It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications and equivalent arrangements, will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to its preferred embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications and equivalent arrangements.

Claims

THAT WHICH IS CLAIMED:

1. A system for cooling a wall of a refractory, wherein the refractory surrounds a tank, and wherein the system is positioned adjacent an exterior surface of the wall, the system comprising: at least one plate positioned at a plate angle, wherein the plate angle is measured from a plane parallel to the exterior surface of the wall, and wherein the plate angle is a non-zero angle; and at least one gas source configured to direct a gas between the at least one plate and the exterior surface of the wall of the refractory, wherein the gas maintains a laminar flow along the exterior surface of the wall of the refractory to cool the wall of the refractory.

2. The system of claim 1, wherein the at least one plate comprises carbon steel.

3. The system of any of claims 1-2, wherein the at least one plate comprises a high emissivity coating.

4. The system of any of claims 1-3, wherein the at least one plate defines a first edge and a second edge, wherein the first edge is opposite the second edge, and wherein the first edge is positioned closer to the exterior surface of the wall of the refractory than the second edge.

5. The system of claim 4, wherein the first edge is curved away from the exterior surface of the wall of the refractory.

6. The system of any of claims 1-5, wherein the at least one plate comprises a first plate, and wherein the system further comprises a second plate positioned vertically above the first plate, and wherein the second plate is positioned at a second plate angle, wherein the second plate angle is measured from the plane parallel to the exterior surface of the wall, wherein the second plate angle is a non-zero angle.

7. The system of claim 6, wherein the second plate angle is different than the plate angle.

8. The system of any of claims 6-7, wherein the plate angle is smaller than the second plate angle.

9. The system of any of claims 6-8, wherein the second plate defines a first plate edge and a second plate edge, wherein the first plate edge is positioned closer to the exterior surface of the wall of the refractory than the second plate edge.

10. The system of claim 9, wherein the first plate edge of the second plate is curved away from the exterior surface of the wall.

11. The system of any of claims 1-10, wherein the at least one gas source is a first gas source and a second gas source, wherein the first gas source is positioned closer to the exterior surface than the second gas source.

12. The system of any of claims 1-11, wherein the at least one gas source is positioned at a source angle.

13. The system of claim 12, wherein the source angle is between 3-20 degrees.

14. The system of any of claim 1-13 wherein, the plate angle is between 0.5-20 degrees.

15. A method of cooling a wall of a refractory, wherein the refractory surrounds a tank, the method comprising: positioning at least one plate adjacent an exterior surface of the wall of the refractory, wherein the at least one plate has a first edge and a second edge opposite the first edge, wherein first edge is a first distance from the exterior surface of the wall of the refractory and the second edge is a second distance from the wall of the refractory; positioning a gas source at a source angle that is not perpendicular to the exterior surface of the wall; and expelling a gas as a laminar flow from the gas source, wherein the source angle causes the gas to contact a base of the exterior surface of the wall of the refractory, and wherein the gas reduces a temperature at the exterior surface.

16. The method of claim 15, wherein the at least one plate comprises a high emissivity coating.

17. The method of any of claims 15-16, wherein the second edge of the at least one plate is positioned closer to the gas source than the first edge, and wherein the first distance is smaller than the second distance.

18. The method of any of claims 15-17, further comprising: positioning a second plate defining a first edge and a second edge above the at least one plate such that the first edge of the at least one plate is positioned between the second edge of the second plate and the exterior surface of the wall of the refractory; and positioning a second gas source at a second source angle, such that the second gas source expels gas between the at least one plate and the second plate.

19. The method of any of claims 15-18, wherein the first edge of the at least one plate is curved away from the exterior surface of the wall of the refractory.

20. The method of any of claims 15-19, wherein the source angle is between 3-20 degrees.

21. A cooling system for cooling a wall, wherein the cooling system is positioned adjacent an exterior surface of the wall, the cooling system comprising: a first plate defining a first edge and a second edge opposite the first edge, wherein first edge is a first distance from the exterior surface and the second edge is positioned a second distance from the exterior surface, wherein the first distance is smaller than the second distance, thereby defining a first plate angle with respect to a plane parallel to the exterior surface of the wall, wherein the first plate angle is a non-zero angle; a second plate defining a first edge and a second edge opposite the first edge, wherein the first edge is a third distance from the exterior surface and the second edge is a fourth distance from the exterior surface, wherein the third distance is smaller than the fourth distance, thereby defining a second plate angle with respect to the plane parallel to the exterior surface of the wall, wherein the second plate angle is a non-zero angle, wherein the first edge of the first plate is positioned between the exterior surface and the second edge of the second plate;a first gas source configured to expel a first gas so as to form a laminar flow between the first plate and the exterior surface of the wall of the refractory; and a second gas source configured to expel a second gas so as to form a laminar flow between the first plate and the second plate.

22. The cooling system of claim 21, wherein the first plate and the second plate comprise a high emissivity coating.

23. The cooling system of any of claims 21-22, wherein the first plate angle is smaller than the second plate angle.

24. The cooling system of any of claims 21-23, wherein first plate edge of the first plate is curved away from the exterior surface of the wall, and wherein the first plate edge of the second plate is curved away from the exterior surface of the wall.

25. The cooling system of any of claims 21-24, wherein the first gas source is positioned at a first source angle, and the second gas source is positioned at a second source angle, wherein the first source angle and the second source angle are not perpendicular to the exterior surface of the wall.

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