Patent Application
20230399568
The disclosure relates to a coke oven door sealing unit, a coke oven chamber and a coke oven battery.
During coking, components of the coke oven gas accumulate on the inside of the coke oven doors of the coking chambers of a coke oven. These components can negatively influence the tightness of a coke oven door. In addition, when escaping from a leaky coke oven door, these components may also represent and/or form part of environmentally harmful gases, such as for example carbon dioxide emissions.
In order to reduce the risk of leakages and to maintain the tightness of the coke oven door, prior art sealing concepts of coke oven doors rely on a so-called “metal-to-metal sealing”, according to which a metallic element of the coke oven door directly contacts the metallic coke oven door frame of a coke oven chamber.
U.S. Pat. No. 5,556,515 describes a coke oven door, which includes a metal frame, means for latching the door in a closed position, a sealing member extending around the perimeter of the frame having forward edges adapted to contact a sealing surface on a coking chamber door jamb for effecting a continuous seal. The sealing member is fabricated from a heat resistant metal.
JP S 51 90348 U describes a device for preventing gas from leaking out of a coke oven. JP S 51 103901 A describes a coke oven door having a furnace lid, a door frame, and a leakage prevention device. JP S 48 74846 U describes a coke oven furnace lid and a coke oven furnace in which an annular hollow gasket is inserted. DE 7706522 U1 describes a sealing device for a coke oven door.
A sealing system based on a metal-to-metal sealing concept inhibits merely a small possibility for adjusting the coke oven door after said door has been installed. The elements of the metal-to-metal sealing system are rigidly attached to one another.
In order to further reduce the risk of leakages and to further maintain the tightness of the coke oven door, it is also necessary to clean the coke oven door regularly. In consequence mechanical or pneumatic cleaning methods have to be regularly applied for declogging the door. However, existing coke oven doors have elements and/or sections that are rather difficult to clean by operators. For example, existing coke oven doors are provided with so-called “double knives” forming a U-shaped channel when viewed in a cross-sectional profile. These double knives provide a double sealing surface for the coke oven door. However, the space enclosed by said double knives cannot be cleaned manually, so that robots distributing a pressurized medium, like for example water at approximately 40 bar, are used to clean such coke oven doors. Despite regular cleaning procedures, it remains necessary to apply rather high forces on the coke oven door to maintain a proper sealing pressure between the double knives of the coke oven door and the coke oven door frame, respectively coke oven frame.
A coke oven chamber of a coke battery may be one out of a plurality of coke oven chambers of a coke battery. For example, a conventional coke oven chamber may be approximately 8 meters high, approximately 20 meters wide and approximately 60 centimeters thick. In a coke oven battery, the coke oven chamber is usually arranged between two heating walls which may be operated alternately to heat the heating chamber respectively coke oven chamber. Along the walls of the coke oven chamber and inside the coke oven chamber, different temperatures regularly prevail at different points. In other words, there are strong temperature gradients on the walls and inside the coke oven chamber. When the oven is started up, for example after being filled with coal, the uneven temperature distribution may cause sections and/or elements of the oven to expand to different degrees or at different rates. The coke oven door frame as well as the coke oven door are regularly cooled by natural air convection and exposed to temperatures up to approximately 300° C. on the outer (shell) side.
The differences in temperatures cause a bending of the coke oven door frame and the coke oven door due to thermal expansion. The bending also causes an uneven surface between the coke oven door frame and the coke oven door. In consequence, the metal-to-metal sealing tends to become prone to leakages. Any leakage that occurs may even cause further soiling or clogging between the coke oven door and the coke oven door frame.
In case a leakage is detected, operators often try to seal the leakage and to maintain the tightness between the coke oven door and the coke oven door frame. For this purpose, manual tightening and/or sealing methods are carried out by operators. For example, operators try to stop leakages by applying a hardening liquid or a sealing paste, which is time and cost intensive. In addition, the appliance of said substances is often also very inefficient, since further leakages might still develop due to further bending of the coke oven door and/or the coke oven door frame during the coking process.
The disclosure provides a coke oven door sealing unit, a coke oven chamber and a coke oven battery, which reduce the occurrence of leakages. This is achieved by a coke oven door sealing unit, a coke oven chamber and a coke oven battery according to the disclosure.
The present disclosure is based on the finding that a particular arrangement of the elements of a coke oven door sealing unit may constitute a self-adjusting mechanism which is not affected by thermal deformation of the coke oven door and/or coke oven door frame.
The present disclosure relates to a coke oven door sealing unit for sealing a coke oven door against a sealing surface of a coke oven door frame of a coke oven chamber. The coke oven door sealing unit comprises a coke oven door for fitting into the coke oven door frame of the coke oven chamber and a fixture device for holding a sealing piece opposite to the coke oven door frame in a peripheral area of the coke oven door. The sealing piece is configured to be operated in a first operating state or a second operating state. The coke oven door sealing unit further comprises a seal protection element for isolating the sealing piece from the coke oven chamber. In a first operating state, the sealing piece is spaced at a first distance from a sealing surface arranged opposite of the sealing piece. In a second operating state, the sealing piece contacts the sealing surface, such that in the second operating state, the sealing piece and the seal protection element at least partially form a cavity.
The self-adjusting mechanism is based on a so-called “radial tightening principle”, which is rather insensitive to thermal deformation and therefore—in contrast to an “axial tightening principle”—does not require a particularly rigid connection between door body and frame. According to the radial tightening principle, forces for sealing the coke oven door against the coke oven door frame are applied radially along a sealing surface. In consequence, the coke oven door sealing unit is less prone to thermal deformations of its elements. In addition, the present disclosure also allows a faster cleaning and an easy maintenance of the coke oven door sealing unit due to the appliance of interchangeable elements. As a result, the occurrence of leakages is effectively reduced.
The volume of escaping coke oven gasses is significantly reduced due to the self-adjusting sealing mechanism and the arrangement of a flexible and gastight sealing piece. The number of leakages during coking requiring operators to apply manual tightening and/or sealing methods is consequently considerably lowered. Thus the operability of the coke oven is particularly enhanced.
The negative environmental impacts caused by escaping coke oven gasses are significantly reduced.
“Coke oven door” refers to any openable and/or closable element or door which is configured to separate the coke oven chamber from an external environment of the coke oven chamber of a coke oven battery. The coke oven door may present as a door, a cover, a flap, a hatch, a port, a lid, a cap or a similar closing device. An inner side of the coke oven door is configured to be in contact with the inner room of the coke oven chamber, so that the inner side of the coke oven door contacts the hot coal and/or coke during coking. Usually, the inner side is configured in a fireproof manner and presents a fireplug for protruding into the inside of the coke oven chamber, wherein said fireplug is configured to prevent heat loss. Often-, the coke oven chamber has two coke oven doors that are arranged opposite to each other. The first coke oven door may be referred to as coke oven door at a “pusher side”. The pusher side is a side that is configured to allow a machine to push the coal and/or coke to the other side of the coke oven chamber, which is referred to as the “coke side”. The coke oven door enables the filling and/or removal of material into or from the coke oven chamber. Furthermore, coke oven doors prevent coal/coke and coke oven gases from escaping the coke oven chamber.
“Coke oven door frame”, respectively frame/coke oven frame, refers to a frame around an opening which may be closed by the coke oven door. When the coke oven door is in a closed position, the coke oven door frame or at least a part of the coke oven door frame is in direct contact with the coke oven door or elements of the coke oven door.
“Sealing surface of a coke oven door frame” refers to a surface, surface portion or an area which directly contacts the coke oven door, in particular which directly contacts a sealing piece of the coke oven door, when the coke oven door is in a closed position. The sealing surface may for example be a smooth surface on the coke oven door frame and/or a lateral surface of a collar member of the coke oven door frame. The collar member may be an integral part of the coke oven door frame or fixedly attached to the coke oven door frame.
“Sealing piece” refers to any suitable element for sealing the coke oven door against the coke oven door frame. In particular, sealing piece refers to a non-metallic element which is configured to seal the coke oven door against the coke oven door frame. For example, the sealing piece may comprise or be formed of a silicone especially of a so-called high-temperature silicone, a ring-like silicone gasket, a sealing rubber, an inflatable seal, a (glass, ceramic) fiber seal and/or a mixture thereof. Further for example, an elastic material may be formed of or comprise a plastic, a synthetic material, a caoutchouc material, a similar material or mixtures thereof. Additional or alternative suitable materials and/or products for forming the sealing piece may comprise or consist of at least one of the following: a silicone (e.g. VMQ, FVMQ), a styrene butadiene rubber (SBR), an ethylene propylene (EPDM), a chloroprene (CR), a nitrile-rubber (NBR), a hydrogebated-nitril-rubber (HNBR), a viton fluorcarbon-rubber (FKM) or a similar material. The use of a sealing piece formed of an elastic material may ease the (auto-) adjustment of the sealing piece when the coke oven door is closed. The sealing piece prevents oven gases from escaping the oven when the coke oven door is in a closed position. In addition, the sealing piece also contributes to the thermal insulation of the coke oven chamber.
“Fixture device for holding a sealing piece” refers to a constructional element or several interconnected elements configured to at least partially hold and/or receive the sealing piece. The fixture device may be arranged on the coke oven door. For example, the fixture device may have a force- and/or form-fit and/or material and/or frictional connection with the coke oven door. Alternatively, the fixture device can also be made in one piece respectively integral with the coke oven door. The fixture device holds and/or retains the sealing piece. In addition, the fixture device may also at least partially form an insulation for the sealing piece against coke oven gases and/or high temperatures.
“Peripheral area of the coke oven door” refers to an edge and/or edge area of the coke oven door. The peripheral area of the coke oven door may be located on the inner side of the coke oven door. The inner side of the coke oven door is the side facing the coke oven chamber. For example, the peripheral area of the coke oven door may be the area encircling and/or surrounding the fireplug. Further for example, the peripheral area of the coke oven door may be the area wherein the sealing piece and/or the fixture device for holding the sealing piece is located. The fixture device may, for example, be positioned so as to be flanged to and/or flush with an edge of the coke oven door.
“First operating state” refers to an operating state of the sealing piece. For example, in case the sealing piece comprises or is formed of an inflatable seal, the first operating state may refer to the state wherein the seal is deflated. Similarly, the “second operating state” refers to an operating state of the sealing piece that is different to the first operating state. For example, in case the sealing piece comprises or is formed of an inflatable seal, the second operating state may refer to the state wherein the seal is inflated by a pressurized medium and wherein, consequently, the inflatable seal is expanded.
“Seal protection element” refers to a constructional element of the coke oven door which forms an isolating/insulating barrier against the coke oven chamber in a state wherein the coke oven door is closed. The seal protection element may for example present as a metallic bendable plate, strip, bar or spring-shield. In a closed state of the coke oven door, the seal protection element has one side facing the coke oven chamber, respectively delimits a part of the coke oven chamber, whilst contacting the coke oven door frame at an end portion of the seal protection element. The seal protection element may have a concave, convex, bended, curved or angled profile. The seal protection element prevents/avoids/diminishes/reduces that coke oven gases contact the sealing piece during coking. In addition, the seal protection element also presents a thermal insulation/barrier against the heat inside the coke oven chamber.
“Spaced at a first distance from a sealing surface arranged opposite of the sealing piece” refers to a distance, a spacing or a gap between the sealing surface and the sealing piece.
“Cavity” refers to a volume or a void, hollow or empty space that may at least partially be formed when the coke oven door is closed and the sealing piece contacts the sealing surface. The cavity may be completely or partially closed. For example, in case the sealing piece comprises or is formed of an inflatable seal, the cavity may be formed between a portion of the sealing piece and a portion of the seal protection element when the coke oven door is closed and the inflatable seal is inflated and, thus, in the second operating state. In other words, when the coke oven door is closed and the sealing piece is operated in its second operating state, the cavity is arranged between the sealing piece and the seal protection element, respectively a portion of the sealing piece and a portion of the seal protection element. In other words, the sealing piece and the seal protection element at least partially form, respectively delimit, a cavity. The cavity may usually be filled with a gas, such as air. In consequence, a heat transfer by conduction, for example a heat conduction through metal, may be diminished or prevented in this area. In consequence, the cavity presents a thermal insulation to the sealing piece adjacent to the cavity. The thermal load applied on the sealing piece may therefore be significantly reduced. This reduction also allows the use of sealing pieces formed of sealing materials that would otherwise not be applicable to the coke oven door due to the high operating temperatures.
In an embodiment, the sealing piece comprises a hollow body for retaining a medium, and/or comprises a glass-fiber packing and an integrated flexible core element enclosed by the glass-fiber packing.
“Hollow body” refers to a tubular or hose-like structure of the sealing piece. For example, the sealing piece may be an inflatable seal. The hollow body of the inflatable seal may be filled with a medium (e.g. gas, water, oil, etc.), which in consequence leads to an expansion of the inflatable seal. Due to the expansion of the inflatable seal, the inflatable seal may contact a sealing surface, for example a sealing surface of the coke oven door frame.
“Medium” refers to a liquid, fluid, gas, solution, emulsion or similar structure or substance. For example, air may be used as medium. Further for example, the medium may be pressurized. In other words, the medium may have a higher pressure than an atmospheric pressure. Due to the hollow body filled with the medium, the sealing piece may apply a radial tightening and adjust itself to the sealing surface.
“Glass fiber packing” may refer to a packing with a core element, for example a flexible core element. The core element may be formed of a high-temperature glass fiber yarn that may be reinforced with fire-resistant impregnation and/or a reinforcement. The flexile core element and/or the glass fiber packing may additionally or alternatively comprise or be formed as an inflatable and/or an expandable seal.
In an embodiment, the sealing piece is formed of an elastic material. An elastic material refers to a material with an enhanced elasticity. Elasticity is the property of a body and/or material to change its shape when force is applied and to return to its initial form when the force is removed. For example, an elastic material may be a silicone, a rubber, a plastic, a synthetic material, a caoutchouc material, a similar material or mixtures thereof. The use of a sealing piece formed of an elastic material may further ease the (auto-) adjustment of the sealing piece when the coke oven door is closed.
In an embodiment, the sealing piece presents a ring-shaped structure to the sealing surface. A “ring-shaped structure” may be a structure which end-parts are connected to one another. A sealing piece in a ring-shaped structure allows to completely seal the sealing surface against the coke oven door. In consequence, an emission of coke oven gases may be prevented completely or at least largely diminished.
The coke oven door sealing unit further comprises a first insulation element for thermally insulating the sealing piece, wherein the first insulation element is arranged between the fixture device and the seal protection element.
“Insulation element” refers to a constructional element for insulating, in particular for thermally insulating, an element against its environment. For example, the insulation element may be formed of or comprise a mica, a silicate mineral and/or a phyllosilicate mineral or mixtures thereof. The thermal conductivity of the insulation element may differ from that of its adjacent components. For example, the insulation element may have a lower thermal conductivity than the fixture device. The arrangement of an insulation element may further reduce a heat transfer to the fixture device and the sealing piece hold by the fixture device.
In an embodiment, the sealing surface is arranged on the coke oven door frame. A sealing surface that is directly arranged on the coke oven door frame allows to modify already existing coke oven doors and coke oven door frames.
Alternatively, in an embodiment, the coke oven door sealing unit further comprises a collar member extending from the coke oven door frame, wherein the sealing surface is arranged on at least a portion of the collar member.
A “collar member” refers to a constructional element that extends and/or protrudes from the coke oven door frame or a surface of the coke oven door frame. The collar member may be an integral part of or attached to the coke oven door frame. The collar member may be formed of a metallic material. The collar member may have a rectangular shaped, an L-shaped, I-shaped, concave, convex, angled, tapered or C-shaped profile. The Collar member may have the sealing surface arranged on one side or side portion. The sealing surface is configured to contact the sealing piece in its second operating state. Another side or side portion of the collar member is cooled by air of its environment. The collar member may therefore function as a cooling fin. The arrangement of a collar member allows that a portion of the heat transferred by the coke oven door frame to the collar member is dissipated to the environment, thus reducing the heat load transferred to the sealing piece on the sealing surface. In addition, the arrangement of a collar member allows a lateral sealing to be applied, which further eases the auto-adjustment and radial tightening of the sealing piece.
In an embodiment, the collar member is integral with the frame. “Integral with the frame” refers to an arrangement, wherein the collar member and the frame, respectively a portion of the collar member and a portion of the frame, are formed from one piece or blank.
In an embodiment, the collar member has a rectangular-shaped, L-shaped, I-shaped, concave, convex, angled, curved or C-shaped profile. A “profile” may refer to a cross-sectional profile. The profile of the collar member may be adapted to different temperature and environmental conditions. The shape of the collar member defines the amount of heat transferred to the environment and/or the sealing piece.
In an embodiment, the coke oven door sealing unit further comprises a second insulation element for thermally insulating the sealing piece, wherein the second insulation element contacts at least a portion of the collar member and a portion of the coke oven door frame. The arrangement of a second insulation element may decrease the heat quantity transmitted to the collar member, so that in consequence the heat transmitted on the sealing surface can be further reduced.
In an embodiment, the fixture device comprises a groove for holding the sealing piece, wherein the sealing piece is frictionally and/or form-fit connected to the groove. The two parallel wall sections of a groove constitute two additional heat dissipating structures, which act like cooling fins.
In an embodiment, in the first operating state, a depth of the groove is greater than the depth of the sealing piece. In an arrangement wherein the depth of the groove is greater than the depth of the sealing piece and wherein the sealing piece is in its first operating state, the groove has two parallel wall sections which are not in contact with the sealing piece, but with their surrounding environment. These sections may be air cooled particularly fast, so that a heat transfer to the sealing piece may be reduced. In addition, an arrangement wherein the groove has a greater depth than the depth of the sealing piece allows the sealing piece to slip back into the groove when changing from the second operating state to the first operating state.
In an embodiment, in the first operating state, the depth of the groove is smaller than or identical to the depth of the sealing piece. An arrangement wherein the depth of the groove is smaller than or identical to the depth of the sealing piece allows to provide a particularly material-saving design, which is especially suitable for quick sealing operations.
The disclosure also concerns a coke oven chamber comprising a coke oven door sealing unit. A coke oven chamber having a coke oven door sealing unit is less prone to leakages of emissions and/or coke oven gases. In addition, the coke oven doors of coke oven chambers having a coke oven door sealing unit may be cleaned and maintained more easily by operators. A plurality of coke oven door sealing units may be arranged at opposite sides or different locations of the coke oven chamber. The aforementioned improvements and embodiments of the coke oven door sealing unit apply also to the coke oven chamber.
The disclosure also concerns a coke oven battery comprising a coke oven door sealing unit. A coke oven battery having a plurality of coke oven chambers each having one or more coke oven door sealing units is less prone to leakages and may emit a reduced amount of coke oven gases. The aforementioned improvements and embodiments of the coke oven door sealing unit apply also to the coke oven battery.
Further aspects and features of the present disclosure derive from the dependent claims, the attached drawing and the following description of the embodiments.
Embodiments of the disclosure are now described by way of example and with reference to the attached drawings, wherein
The hatched surface of sealing piece 13 in
In the embodiment shown in
In the second operating state of the sealing piece 13, a cavity 32 is formed between a portion of the sealing piece 13 and the seal protection element 30. The seal protection element 30 in
The first insulation element 14 is arranged on the coke oven door 1 between a portion of the fixture device 11 and the seal protection element 30. The second insulation element 23 is arranged between a portion of the coke oven door frame 20 and a portion of the collar member 22. Both, the first insulation element 14 and the second insulation element 23, may comprise or be formed out of a mica or a similar material. The first insulation element 14 and the second insulation element 23 present a thermal isolation/insulation against the heat of the coke oven door frame 20 and the coke oven chamber 31. The first insulation element 14 and the second insulation element 23 thereby contribute to the thermal isolation and/or insulation of the sealing piece 13.
In contrast to the embodiments shown in
In
The discussed examples are embodiments of the disclosure. In the case of the embodiments, the described components of the respective embodiment each represent individual features of the disclosure which are to be considered independently of each other and which also further develop the disclosure independently of each other. The features are thus also to be regarded as components of the disclosure individually or in a combination other than the combination shown. Furthermore, the described embodiments can also be supplemented by further features of the disclosure already described.
Further features and embodiments of the disclosure result for the skilled person in the context of the present disclosure and the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| LU102177 | Nov 2020 | LU | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2021/080534 | 11/3/2021 | WO |
