Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23M—CASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
  • F23M5/00—Casings; Linings; Walls
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23M—CASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
  • F23M5/00—Casings; Linings; Walls
  • F23M5/04—Supports for linings
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23M—CASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
  • F23M5/00—Casings; Linings; Walls
  • F23M5/06—Crowns or roofs for combustion chambers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23M—CASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
  • F23M5/00—Casings; Linings; Walls
  • F23M5/08—Cooling thereof; Tube walls

Definitions

• the present invention relates to a furnace wall assembly of an industrial furnace with a furnace wall and with at least one on one side attached to an inner side of the furnace wall protective element made of refractory material.
• the furnace walls are protected by the protective elements from heat and flue gas, which arise in the inside of the furnace or boiler combustion chamber.
• the furnace wall is formed, for example, as a closed boiler tube wall and optionally on the ground as a broken through Lüftungssch strand rust.
• the boiler tube wall is formed, for example, from parallel pipes connected to one another via pipe fins or to individual, partially back-fixed pipes.
• the tubes are usually flowed through by a cooling fluid.
• the cooling fluid used is preferably water whose boiling point can be adjusted to over 250 ° C. by a correspondingly high pressure.
• Holes of the holding elements are pushed to anchor the protective elements to the holding elements.
• the gap between the furnace wall and protective element is in the prior art in the operation of the furnace partially by a purge gas or a slit medium, as a so-called ventilated system, such as air, flows through to separate corrosive gases that arise in the combustion chamber as well as possible from the furnace wall ,
• a poor heat transfer between the protective element and the furnace wall is disadvantageous because heat is transported almost only by heat radiation and hardly by heat conduction.
• the protective elements on the combustion chamber side have a high surface temperature, which leads to premature wear of the protective elements and low heat extraction from the respective zone of the boiler.
• a better heat transfer between the protective element and the furnace wall is achieved by filling the gap with mortar or by pouring the gap with cement.
• the intermediate space is filled with an adhesive, which at the same time serves to secure the protective elements to the furnace walls.
• a disadvantage of this solution is a relatively high installation and disassembly effort during repair work.
• the object is achieved by a furnace wall arrangement of the type defined above, which has arranged between the inside of the furnace wall and an outer side of the protective element cooling fins, wherein the cooling fins have a specific thermal conductivity, in particular greater than specific istleitzuen one between the furnace wall (2) and the protective element (3) located gap medium, a between two protective elements arranged mortar or cement and the protective element (3).
• the cooling fins ensure good heat dissipation from the protective elements into the furnace wall. As a result, the protective elements are cooled from their backs, which has an advantageous effect on the life of the protective elements.
• the cooling ribs are elongate profile rods which are partially partially and / or non-positively arranged in matching with the cooling fins grooves which are formed in the protective element.
• the profile bars are in a useful embodiment long rectangular solid profiles, in particular in the form of strips.
• the profile bars have no filled cross section, but their cross section occupies only parts of a surface, for example, occupies a U-shaped profile three edges of a surface.
• the cooling fin is constructed in layers of a graphite foil to the desired thickness.
• strips of graphite foil having a thickness, in particular in the range from 0.4 to 1 mm, are stacked on top of one another and if necessary glued together.
• the rod-shaped configuration of the cooling fins is particularly advantageous if the furnace wall also has linearly extending structures, for example tubes.
• the cooling fins are in this case preferably arranged parallel to the linear structures of the furnace wall, so that large contact surfaces between the furnace wall and the cooling fins result, which in turn cause good heat conduction from the cooling fins in the furnace wall.
• the grooves in the protective elements ensure large contact surfaces between the protective elements and the cooling ribs and thus good heat conduction from the protective elements into the cooling ribs.
• the cooling fins can advantageously be mechanically fastened or glued in the grooves.
• a purge gas can be passed between adjacent linearly extending cooling fins, the cooling fins serving as the channel walls of a purge gas channel. At Spülgaszu exiten and purge gas discharges of the furnace are usually no adjustments required.
• the cooling fins have other than elongated shapes, such as circular.
• the profile bars have an I-shaped cross-section or a cross-section in the form of a trapezoidal tapered "I" s, the wider side of the trapezoid engaging in the Oven wall and the narrower side of the trapezoid is provided in the groove of the protective element.
• the cooling fins have particularly simple geometric shapes, which allow a particularly simple manufacture and processing of the cooling fins.
• other profile bars are used, for example, those whose cross section is composed of a circular arc and radially extending from the circular arc straight ribs or layered graphite foil.
• the cooling ribs are glued into the protective element.
• the adhesive ensures a good thermal contact, for a gas-tight connection and also for a mechanical pre-assembly, which ultimately contributes to ease of assembly and disassembly of the furnace wall assembly.
• cooling fins are attached to the furnace wall, for example glued, screwed, clamped or soldered.
• the cooling fins are made of a heat-resistant elastic material.
• a heat-resistant elastic material As a result of the elasticity which is also present under thermal cycling, such cooling fins, when clamped in the installed state between the furnace wall and the protective elements, remain permanently in a mechanical contact with the furnace wall and on the protective element.
• the cooling fin material is soft and only exerts small forces on the clamping components during elastic deformation. Of the pressed on the furnace wall cooling fins only permissible small pressure forces are exerted on the protective elements, so that the protective elements are not damaged.
• the heat-resistant elastic sealing material is expanded graphite.
• This material is characterized by a good thermal conductivity, elasticity and a good chemical resistance to corrosion by flue gas.
• the specific thermal conductivity of the material used is preferably 100 W m "1 K " 'large or larger. Consequently, this material is particularly well suited to the formation of cooling fins.
• other materials such as metal bellows or metal foams are used.
• the cooling fins are constructed in layers of a Graphitfol ie.
• Graphite foil is flexible because of its small thickness. Multilayer arrangements of the graphite foil are processed in embodiments of the invention, for example as a lamellar stack or as a curl, in particular to a flexible seal.
• the furnace wall assembly according to the invention is dimensioned such that the occurring temperatures of the cooling fins always remain below 600 ° C.
• the insides of the protective elements are facing the combustion chamber in the high temperatures of, for example, 1 1 50 ° C prevail. This heats the inner surface of the protective elements.
• temperatures up to greater than 1000 ° C. were measured on the surfaces of the inside of the protective elements.
• the outer sides of the protective elements are cooled, so that they have a lower surface temperature. Accordingly, the protective element in the furnace wall assembly according to the invention are generally well cooled, so that temperatures occurring low and the durability of the protective elements is high.
• the cooling fins are thermally conductively connected to the outer sides of the protective elements, so that they assume almost the same temperatures, at least in the vicinity of the boundary surfaces with the protective elements. Excessive temperatures can damage the cooling fins, for example, oxygen can oxidize graphite at temperatures above 600 ° C. Accordingly, material thicknesses and other parameters that affect the temperatures occurring are set so that predetermined temperature limits are not exceeded.
• At least one graphite foil is arranged on the furnace wall, wherein the graphite foil is clamped between adjacent cooling ribs.
• the good chemical resistance of graphite is exploited in order to cover areas of the furnace wall which are at risk of corrosion and to protect against chemical stress by flue gas.
• the furnace wall is designed as a boiler tube wall, in which parallel tubes are connected to one another via pipe fins, or as a grate.
• Side walls and ceilings of industrial furnaces are often designed as boiler tube walls.
• the boiler tube walls are protected by plate-shaped protective elements. clothes, the sides of which are partially profiled inversely to the boiler tube walls to ensure constant distances between the furnace wall and the protective element.
• the rust is to be understood as a furnace wall, which is part of a furnace wall arrangement according to the invention as well as the protective element as such.
• the protective elements are preferably formed as waisted plates, that is as plates, which are formed at two opposite ends with recesses, in particular those with tei lnikförmigem cross-section, wherein the recesses surround the tubes of the furnace wall with distance.
• the cooling fins are preferably received in the region of these recesses and pass through the gap-shaped annular space between the recess and the tube.
• the plates are arranged above and next to each other to form the furnace wall assembly and are guided loose, so that a fixing to the furnace wall can be omitted.
• these plates pass through the space between adjacent tubes and project on both sides of the tube plane.
• the plates are constructed of the same material as described above, which also applies to the cooling fins.
• the material of the cooling fins can be suitably selected, but graphite is preferably used.
• the advantage of the described embodiment is a very good protective function. Furthermore, the tubes are more or less completely surrounded by the cooling fins. The assembly is very simple and separate fasteners against the furnace wall are unnecessary.
• Fig. 2 shows a protective element of the arrangement of Figure 1 in a perspective view on its back, as well as
• Fig. 3 shows a further embodiment of a furnace arrangement in perspective.
• Fig. 1 shows schematically a preferredandsbeispiei a furnace wall assembly 1 according to the invention in cross section. Illustrated components of the furnace wall assembly 1 are a furnace wall 2, protective elements 3 and between an inside 4 of the furnace wall 2 and outer sides 5 of the protective elements 3 clamped cooling fins. 6
• the furnace wall 2 is in the illustrated variant a boiler tube wall, which tubes 12 and pipe fins 13 has. Through the tubes 12 water is passed during operation of the furnace, through which heat is removed from the furnace wall 2.
• the protective elements 3 Aufhssenaus traditions 1 1 are formed, with which the protective elements 3 are suspended from holding elements 10, wherein the holding elements 10 are arranged on the furnace wall 3, in particular fixed.
• the protective elements 3 are made of silicon carbide plates. In other embodiments, the protective elements 3 are formed of other refractory materials. Between adjacent protective elements 3 there are joints 8, which are grouted with suitable mortar 9, for example a SiC mortar or cement.
• cooling fins 6 are clamped, which in the illustrated embodiment, preferably elastic and in particular made of expanded graphite rods or strips, here for example, and preferably cuboid bars with an I-shaped cross-section.
• the cooling fins 6 and the grooves 7 clearly have larger linear expansions than the illustrated cross-sectional edges.
• the cooling fins 6 are suitably against the furnace wall 2 and to the wall elements, so that a good heat conduction from the wall elements 3 is ensured via the cooling fins 6 in the furnace wall 2.
• 2 shows schematically a perspective view on the outside 5 of a wall element 3.
• the edge of the wall element 3 shown in front is a cutting edge, on which the structure of the grooves 7 and the suspension recess 11 can be seen well.
• the grooves or joints 7 strips are used with a trapezoidal cross section in a preferred embodiment, not shown, with a measured between the parallel sides of the trapezoid width 10 mm, a measured at the wide side of the trapezoidal length 8 mm and an the narrow side of the trapezium measured length is 7 mm, which is preferred, but only by way of example.
• the cooling fins are in embodiments preferably made of the expanded graphite material "Ecophit L".
• FIG. 3 again shows, purely schematically and in perspective, a part of a further embodiment of a furnace wall arrangement according to the invention.
• the furnace wall is gebi Ldet by spaced tubes 12, which span, so to speak, a boiler tube wall, wherein during operation of the furnace through the tubes cooling water is passed to dissipate heat.
• the protective elements 3 designed as waiststones are provided, on two opposite sides facing the tubes 12, with recesses 22, similar to the first exemplary embodiment, which here preferably have a semicircular cross section.
• the corresponding cooling fins 6 are added. These cooling fins are in turn in contact with the tube 12 and the Tai llenstein and are also accessiblebi end, especially material designed according to the first embodiment, that is preferably formed of heat-resistant material, in particular expanded graphite with particular elastic material properties.
• the waist stones are plate-shaped and - as has already been stated above, according to the height of the furnace wall order according to many stacks stacked and arranged side by side, so that compared to the formation of the protective elements in Figures 1 and 2, the protective elements and the free space between the Pass through tubes 12 and beyond ebenfal ls projecting on both sides and also in combination with the juxtaposed waist stones 20, the tube 12 substantially fully enclose, so that the cooling fins 6 are distributed so to speak over the entire circumference of the tubes 12. This increases the efficiency in this embodiment.
• the waist blocks 20 are materially designed according to the support elements 3 explained in connection with the first embodiment. Advantage of this embodiment is that the plates no longer need to be attached to one side of the furnace wall, but loosely guided along the tubes 12 and arranged.
• the waist panels have dimensions of 147 x 1 76 mm in length and width and a thickness of 1 00 mn.
• the pipe spacing can be 150 mm with a pipe diameter of 57 mm.
• the waist stones are preferably 223 x 1 87 x 64 mm.
• Advantageous properties of graphite are high thermal conductivity and high chemical resistance to aggressive gases released in the furnace.
• the heat resistance of graphite in air is sufficiently high for the application described because the graphite is cooled by the pipe wall.
• the orientation of the cooling fins which are in particular graphite strips along the tubes of the tube wall and along the protective elements extending along the tubes, ensures a high heat transfer from the protective element into the furnace wall. This contributes to a considerably higher efficiency of the furnaces compared to furnaces with ventilated protective elements.
• the surface temperature at the hot side of the protection element is smaller than in the prior art.
• the protective elements have an increased life.
• the adhesion of fly ash and slag is less pronounced than in the prior art.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Furnace Housings, Linings, Walls, And Ceilings (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

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Citations (5)

Family Cites Families (5)

• 2013
  • 2013-11-12 DE DE102013018936.5A patent/DE102013018936B4/de not_active Expired - Fee Related
• 2014
  • 2014-10-31 WO PCT/EP2014/002930 patent/WO2015070953A1/de active Application Filing
  • 2014-10-31 EP EP14796416.7A patent/EP3069079B1/de active Active
  • 2014-10-31 DE DE202014009337.7U patent/DE202014009337U1/de not_active Expired - Lifetime
  • 2014-10-31 PL PL14796416T patent/PL3069079T3/pl unknown

Patent Citations (5)

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