A heat exchange chamber of a coke oven and a coke oven

Abstract

The present invention discloses a heat exchange chamber of a coke oven, which comprises a chamber body. The interior of the chamber body is of a multi-layer structure, and an air passage and a flue gas passage are respectively arranged in each layer of the multi-layer structure, so that the layers of the multi-layer structure are sequentially communicated with each other. The air passage is used for communicating with the external environment, and the flue gas passage is used for communicating with the vertical flue of the combustion chamber in the coke oven. The present invention also provides a coke oven adopting the above heat exchange chamber. The structure of the heat exchange chamber of the present invention is simple and can effectively improve the heat exchange efficiency of the coke oven.

Description

Technical Field

[0001] The present invention belongs to the technical field of coking, and particularly relates to a heat exchange chamber and a coke oven including the heat exchange chamber. Background Art

[0002] In the coking industry, when using a coke oven for coking, the heat generated by the combustion of raw gas and air is usually used to heat the carbonization chamber to carbonize the coal charge.

[0003] In a conventional regenerative coke oven, a regenerator is currently arranged below the combustion chamber. The regenerator first preheats the combustion-supporting gas and the raw gas simultaneously, and then makes them mix and burn in the combustion chamber. This kind of regenerator has a complex structure, poor heat exchange effect, large gas resistance, large pressure drop, and is prone to gas leakage. At the same time, since the temperature of the combustion chamber can reach 1280°C - 1400°C, it causes great damage to the wall of the combustion chamber. For heat recovery coke ovens, mainly horizontal coke ovens and a few vertical coke ovens are used. Currently, neither of the above two types of coke ovens has a regenerator nor a preheating link.

[0004] The above two types of heat recovery coke ovens each have their own characteristics. For the horizontal coke oven, due to the large floor area and high investment cost of the horizontal coke oven structure, the width of the coal cake reaches 3 - 4m. The too-wide carbonization chamber seriously affects the heat transfer effect, and the coking time is too long. Moreover, the direct heating method is mostly used, and 1.5 - 4% of the coal and coke will burn to supplement the heat required for coal dry distillation, resulting in reduced production capacity. For the vertical coke oven, when the volatile matter of the blended coal in the existing vertical (heat recovery) coke oven is low, the heat required for coal dry distillation cannot be self-sufficient, and additional gas needs to be supplemented for combustion, resulting in low heating efficiency. Moreover, since the coking periods of different carbonization chambers are different and the amounts of raw gas generated are different, the heating of the coke oven is uneven and the coking time is long. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a heat exchange chamber of a coke oven and a coke oven including the heat exchange chamber, which have a simple structure and can improve the heat exchange efficiency of the coke oven, aiming at the above deficiencies in the prior art.

[0006] According to one aspect of the present invention, a heat exchange chamber of a coke oven is provided, and its technical solution is as follows:

[0007] A heat exchange chamber of a coke oven includes a chamber body. The interior of the chamber body is a multi-layer structure, and an air passage and a flue gas passage are respectively arranged in each layer of the multi-layer structure so that the layers of the multi-layer structure are sequentially connected.

[0008] The air passage is used to communicate with the external environment, and the flue gas passage is used to communicate with the vertical flues of the combustion chamber in the coke oven.

[0009] Preferably, the multi-layer structure includes an air cushion layer and a heat exchange layer. The air cushion layer is disposed at the bottom inside the chamber body, and the heat exchange layer is disposed above the air cushion layer.

[0010] Preferably, the heat exchange layer includes a first heat exchange horizontal layer, a second heat exchange horizontal layer, and a third heat exchange horizontal layer, which are arranged in sequence from bottom to top.

[0011] In the first heat exchange horizontal layer, the second heat exchange horizontal layer, and the third heat exchange horizontal layer, the connection points of the air channels corresponding to adjacent two layers are arranged staggeredly, and the connection points of the flue gas channels corresponding to adjacent two layers are arranged staggeredly.

[0012] Preferably, the multi-layer structure further includes a transition layer, which is disposed above the third heat exchange horizontal layer. The air channels and flue gas channels of each layer in the multi-layer structure are separated by partition walls. The flue gas channel corresponding to the transition layer includes a sedimentation area and an ash removal exhaust duct. The sedimentation area is used for sedimenting the dust in the flue gas from the vertical flue, and the ash removal exhaust duct is disposed within the partition wall of the transition layer. Its inlet is disposed at the upper part of the transition layer and communicates with the sedimentation area, and its outlet communicates with the flue gas channel corresponding to the third heat exchange horizontal layer.

[0013] Preferably, grate bricks are provided in the air channel between the third heat exchange horizontal layer and the transition layer to enable air to enter the transition layer evenly; grate bricks are also provided in the flue gas channel between the third heat exchange horizontal layer and the second heat exchange horizontal layer to enable flue gas to enter the second heat exchange horizontal layer evenly.

[0014] Preferably, a plurality of inlets are provided on the air channel in the air cushion layer for inputting combustion-supporting gas, and the plurality of inlets are evenly distributed; a plurality of outlets are provided on the flue gas channel in the air cushion layer for discharging flue gas, and the plurality of outlets are evenly distributed.

[0015] Preferably, the number of the air channels and the flue gas channels are both multiple columns, and the numbers of both are the same. The plurality of air channels and the plurality of flue gas channels are arranged alternately.

[0016] Preferably, the plurality of air channels and the plurality of flue gas channels corresponding to each layer are arranged alternately by partition walls. The partition walls are made of silica bricks. The cross-section of the silica bricks is T-shaped. A groove is provided at its wider end, and a protrusion adapted to the groove is provided at its narrower end.

[0017] The heat exchange chamber of the coke oven of the present invention, when applied to a coke oven, is used to replace the regenerator in the structure of a traditional coke oven. Its structure is simple. Since the heat exchange chamber adopts a multi-layer structure with dual channels for air and flue gas, the heat exchange efficiency can be improved and the heat exchange effect is good. In addition, by setting the air channels and flue gas channels in quarters, the originally long series-connected paths of each layer are changed into four parallel short paths, thereby shortening the flow paths of air and flue gas and reducing the flow resistance, reducing their respective pressure drops, reducing the pressure difference between the two, and further reducing the risk of air and flue gas leakage in the heat exchange chamber, and improving the stability and reliability of the heat exchange chamber.

[0018] According to another aspect of the present invention, there is also provided a coke oven, and its technical solution is as follows:

[0019] A coke oven includes a furnace body. Inside the furnace body, there are a carbonization chamber and a combustion chamber. The combustion chamber includes vertical flues and air channels. The carbonization chamber is communicated with the vertical flues. Among them, there is also a heat exchange chamber inside the furnace body. The heat exchange chamber adopts the heat exchange chamber of the above-mentioned coke oven.

[0020] The air channel of the heat exchange chamber is communicated with the air channel, and the flue gas channel of the heat exchange chamber is communicated with the vertical flue.

[0021] Preferably, the carbonization chamber and the combustion chamber are arranged side by side at the upper part of the coke oven. The coke oven further includes a balance channel. The balance channel is arranged at the top of the carbonization chamber and the combustion chamber and is respectively communicated with the carbonization chamber and the combustion chamber, and is used to evenly distribute the combustible substances generated by the dry distillation of the coal material in the carbonization chamber to the combustion chamber.

[0022] The coke oven of the present invention, due to the setting of the heat exchange chamber, can simplify the structure and improve the heat recovery utilization rate. Since the high-temperature flue gas generated by the combustion chamber only preheats the combustion-supporting air, the temperature of the combustion chamber of the coke oven adopting this heat exchange chamber structure can be appropriately reduced (1100 - 1250 °C), reducing the damage to the wall of the combustion chamber. Specifically, it has the following beneficial effects:

[0023] (1) The heating speed is fast, and the coking time can be shortened.

[0024] Different from the traditional horizontal coke oven, the carbonization chamber of the coke oven of the present invention is set to be tall and thin, and the carbonization chamber and the combustion chamber are arranged side by side, so that the coal cake placed in a tall and thin shape in the carbonization chamber can absorb the heat transferred from the combustion chamber to be dry-distilled into coke, and the contact area between the carbonization chamber and the combustion chamber is increased. Moreover, air is fed into the vertical flue in sections from bottom to top, optimizing the uniformity of the temperature field in the vertical direction (i.e., the height direction) of the vertical flue, canceling the crossover holes and circulation holes in the traditional waste gas circulation type vertical flue, making the entire vertical flue have a reverse flame gas flow, which can transfer heat to adjacent carbonization chambers, improving the heat transfer speed and effect, and shortening the coking time.

[0025] (2) Indirect heating is adopted, without coal loss, and the production capacity can be improved.

[0026] The carbonization chamber and the combustion chamber are arranged side by side and independently of each other, avoiding the combustion heat supply above the carbonization chamber in the prior art, and the burning loss caused by the ignition of the upper part of the coal charge or coke, thus affecting the coke production capacity. Compared with the horizontal coke oven, the tonnage coke output can be increased by 1.5 - 4%.

[0027] (3) The heating is more uniform, and the coke quality and output can be improved.

[0028] By setting a balance channel to evenly distribute the raw gas, the amount and composition difference of the raw gas entering the combustion chamber can be reduced, avoiding the heat difference generated by the combustion in different combustion chambers due to the fluctuation of the raw gas volume in different carbonization chambers at different coking cycles, thereby improving the heating uniformity and further improving the coke quality;

[0029] (4) Thermal recovery is used instead of chemical recovery, simplifying the process flow, reducing the floor area, lowering the energy consumption, and improving the economy.

[0030] The raw gas generated by the dry distillation of the coal charge in the carbonization chamber enters the combustion chamber in a hot state for reasonable combustion. Compared with the chemical recovery process, there is no complex gas collection, heating, and gas flow exchange system, no cumbersome chemical product recovery and gas purification system, sewage treatment workshop, etc. The process flow is simplified, the floor area for infrastructure construction and cost investment are reduced (by more than 40%), which is beneficial to reducing the energy consumption of the coking process and saving water resources (water consumption is less than 0.3m 3 / t coke, power consumption per ton of coke is less than 10 kWh); the sensible heat generated by combustion is directly transferred to the carbonization chamber through the partition wall (furnace wall) for heat supply, which can reduce or avoid the additional energy consumption requirements of the carbonization chamber. By setting a heat exchange chamber, heat recovery is carried out on the high-temperature flue gas generated in the combustion chamber. Not only can the air be preheated, but the flue gas after heat exchange is sent to the waste heat boiler for further utilization (such as power generation, steam production, etc.) through the shortest path (arranging the main flue underground), which can reduce heat loss, realize the cascade utilization of the heat of the high-temperature flue gas, and improve the heat recovery utilization rate.

[0031] (5) The requirements for the coal charge are reduced, and high-quality coal resources are saved.

[0032] A large amount of weakly caking coal and a small amount of non-caking coal can be blended into the coal charge, and the proportion can be increased by nearly 50% compared with the conventional coke oven. To a certain extent, high-quality coal (coking coal and fat coal) is saved, the selection range of coking coal types is expanded, and the produced coke has larger lump size, high carbon content, high strength and low ash content, and the coke quality is good. Description of the Drawings

[0033] Figure 1 It is a schematic structural diagram of the heat exchange chamber of the coke oven in the embodiment of the present invention;

[0034] Figure 2 It is a schematic structural diagram of the coke oven in the embodiment of the present invention;

[0035] Figure 3 It is a schematic diagram of the air flow direction in the heat exchange chamber in the embodiment of the present invention;

[0036] Figure 4 It is a schematic diagram of the flue gas flow direction in the heat exchange chamber in the embodiment of the present invention;

[0037] Figure 5 It is a schematic structural diagram of the silica brick in the embodiment of the present invention;

[0038] Figure 6 It is a schematic structural diagram of the air channel in the embodiment of the present invention;

[0039] Figure 7 It is a schematic structural diagram of the flue gas channel in the embodiment of the present invention;

[0040] Figure 8 It is a schematic structural diagram of the combustion chamber in the embodiment of the present invention;

[0041] Figure 9 It is a schematic diagram of the distribution of the air outlet in the embodiment of the present invention;

[0042] Figure 10 It is a schematic structural diagram of the balance channel in the embodiment of the present invention;

[0043] Figure 11 It is a schematic structural diagram of the inclined flue in the embodiment of the present invention.

[0044] In the figure: 10 - carbonization chamber; 20 - combustion chamber; 21 - first partition wall; 22 - second partition wall; 23 - vertical flue; 24 - air duct; 25 - furnace end; 26 - air outlet; 261 - first outlet; 262 - second outlet; 263 - third outlet; 30 - balance channel; 40 - inclined flue; 41 - first channel; 42 - second channel; 50 - heat exchange chamber; 51 - air cushion layer; 52 - first heat exchange horizontal layer; 53 - second heat exchange horizontal layer; 54 - third heat exchange horizontal layer; 55 - transition layer; 56 - ash removal exhaust gas duct; 57 - grate brick; 58 - air channel; 59 - flue gas channel; 60 - groove; 61 - protrusion; 62 - air inlet; 63 - flue gas outlet; M - raw coke oven gas; F - flue gas; K - air. Detailed implementation manners

[0045] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further clearly and completely described below in conjunction with the drawings and specific embodiments of the present invention.

[0046] The present invention provides a heat exchange chamber for a coke oven, comprising a chamber body. The interior of the chamber body has a multi-layer structure, and an air passage and a flue gas passage are respectively arranged in each layer of the multi-layer structure so that the layers of the multi-layer structure are sequentially communicated with each other.

[0047] The air passage is used to communicate with the external environment, and the flue gas passage is used to communicate with the vertical flue of the combustion chamber in the coke oven.

[0048] Correspondingly, a coke oven is also provided, comprising a furnace body. The furnace body has a carbonization chamber and a combustion chamber. The combustion chamber comprises a vertical flue and an air passage. The carbonization chamber is communicated with the vertical flue. There is also a heat exchange chamber in the furnace body, and the heat exchange chamber of the coke oven adopts the above-mentioned heat exchange chamber of the coke oven.

[0049] The air passage of the heat exchange chamber is communicated with the air passage, and the flue gas passage of the heat exchange chamber is communicated with the vertical flue.

[0050] Embodiment 1

[0051] As Figure 1 shown, this embodiment discloses a heat exchange chamber for a coke oven, comprising a chamber body. The interior of the chamber body has a multi-layer structure. An air passage 58 and a flue gas passage 59 are arranged inside the chamber body. The air passage 58 and the flue gas passage 59 are arranged in parallel and simultaneously penetrate through the multi-layer structure, so that the layers of the multi-layer structure are sequentially communicated with each other. That is, each layer of the multi-layer structure has an air passage and a flue gas passage. The air passages of all layers are connected to form the entire air passage 58, and the flue gas passages of all layers are connected to form the entire flue gas passage 59, so that there is an air passage corresponding to each layer in each layer of the multi-layer structure (which is a section of the entire air passage 58, hereinafter referred to as the air passage of the layer) and a flue gas passage (which is a section of the entire flue gas passage 59, hereinafter referred to as the flue gas passage of the layer). The air passage and the flue gas passage of each layer are separated by a partition wall. The air passage of the lower layer is communicated with the air passage of the upper layer, and the flue gas passage of the lower layer is communicated with the flue gas passage of the upper layer.

[0052] Among them, the air passage 58 is used to communicate with the external environment to input combustion-supporting gas (such as air) in the external environment. The flue gas passage 59 is used to communicate with the combustion chamber in the coke oven, so that the high-temperature flue gas generated in the combustion chamber is discharged and the air passage can be preheated at the same time. The chamber body of the heat exchange chamber is preferably built with bricks made of materials with better heat insulation properties to reduce heat loss.

[0053] In this embodiment, as Figure 2As shown in the figure, the multi-layer structure of the heat exchange chamber includes an air cushion layer 51 and a heat exchange layer, where: the air cushion layer 51 is provided at the bottom inside the chamber body, and the heat exchange layer is provided above the air cushion layer. In some alternative embodiments, the heat exchange layer includes a first heat exchange horizontal layer 52, a second heat exchange horizontal layer 53, and a third heat exchange horizontal layer 54. The three are arranged in sequence from bottom to top and are interconnected through the air channels and flue gas channels of each layer. Moreover, the connection points of the air channels of any two adjacent layers are staggered, and the connection points of the flue gas channels of any two adjacent layers are staggered, finally forming an S-shaped air channel 58 and an S-shaped flue gas channel 59, so that the air flows upward layer by layer in a zigzag manner from bottom to top in the entire column of air channels 58 (as shown in Figure 3 ), and the flue gas flows downward layer by layer in a zigzag manner from top to bottom in the entire column of flue gas channels 59 (as shown in Figure 4 ), thereby extending the heat exchange time and increasing the heat exchange contact area to improve the heat exchange effect.

[0054] The air channels 58 and flue gas channels 59 penetrating through the multi-layer structure can be arranged in one column or multiple columns. In this embodiment, the air channels 58 and flue gas channels 59 are respectively arranged in multiple columns. In this way, each layer in the multi-layer structure has multiple air channels and multiple flue gas channels. Specifically, each column of air channels 58 and each column of flue gas channels 59 penetrate between the air cushion layer 51, the first heat exchange horizontal layer 52, the second heat exchange horizontal layer 53, and the third heat exchange horizontal layer 54 to form the respective air channels and respective flue gas channels of each layer, and the air channels and flue gas channels of each layer are arranged alternately. A grid brick 57 is provided at the part of the flue gas channel 59 between the second heat exchange horizontal layer 53 and the third heat exchange horizontal layer 54. Through the porous structure on the grid brick 57, the high-temperature flue gas of the third heat exchange horizontal layer 54 can be evenly distributed into the flue gas channels of the second heat exchange horizontal layer 53, thereby improving the uniformity of preheating the air in the air channels 58.

[0055] Optionally, multiple inlets are provided on each air channel of the air cushion layer 51 for inputting combustion-supporting gas (air), and the multiple air inlets are evenly distributed. In this embodiment, it is preferably to set four air inlets 62 on each air channel of the air cushion layer, as shown in Figure 6 , and the four air inlets 62 are evenly distributed to make the air enter the heat exchange chamber evenly. The air cushion layer 51 is the first layer for the cold air in the external environment to enter the furnace body. It can isolate and block the downward transfer of heat from the first heat exchange horizontal layer 52, play a role in cooling the bottom of the coke oven, and at the same time can also play a role in protecting the bottom of the coke oven. Multiple outlets are provided on each flue gas channel of the air cushion layer 51 for discharging the high-temperature flue gas generated by combustion in the coke oven, and the multiple outlets are evenly distributed. In this embodiment, it is preferably to set four flue gas outlets 63 on each air channel, that is, to set a four-way flue, as shown in Figure 7 , and the four flue gas outlets are evenly distributed.

[0056] In this embodiment, the heat exchange chamber adopts a quarter heat exchange chamber, that is, each air passage is provided with four air inlets 62, and each flue gas passage is provided with four flue gas outlets 63. The originally long series-connected paths of each layer are changed into four parallel short paths, so that the flow paths of air and flue gas can be shortened and the flow resistance can be reduced, thereby reducing the pressure drop of each, reducing the pressure difference between the two, and further reducing the risk of air and flue gas leakage in the heat exchange chamber (there are certain gaps in the partition wall made of silica bricks, and these gaps will cause gas leakage between the brick walls in the furnace. After adopting the quarter heat exchange chamber, the pressure difference between the air passage 58 and the flue gas passage 59 is reduced, and the leakage phenomenon is weakened), and the stability and reliability of the heat exchange chamber can be improved.

[0057] Optionally, as Figure 2 shown, the multi-layer structure of the heat exchange chamber 50 in this embodiment further includes a transition layer 55. The transition layer 55 is arranged above the third heat exchange horizontal layer. The transition layer 55 is divided into an air passage and a flue gas passage by a partition wall. The air passage of the transition layer is communicated with the air passage of the third heat exchange horizontal layer 54. The flue gas passage of the transition layer 55 includes a sedimentation area and an ash removal exhaust passage 56. The sedimentation area is communicated with the vertical flue 23 of the combustion chamber 20, and is used to receive the flue gas generated by the combustion of the vertical flue 23 and make the dust in the flue gas settle and be intercepted in the sedimentation area of the transition layer. The ash removal exhaust passage 56 is arranged on the wall (partition wall) of the flue gas passage of the transition layer. The inlet of the ash removal exhaust passage 56 is preferably arranged at the upper part of the flue gas passage of the transition layer 55 and is communicated with the sedimentation area, and its outlet is communicated with the flue gas passage of the third heat exchange horizontal layer 54. The dust in the flue gas settles due to gravity in the transition layer. The dust deposited in the sedimentation area of the transition layer 55 is cleaned every once in a while to maintain the ash removal effect of the transition layer 55. The flue gas after ash removal enters the flue gas passage of the third heat exchange horizontal layer 54 through the ash removal exhaust passage 56. A grate brick 57 is also arranged in the part of the air passage between the third heat exchange horizontal layer 53 and the transition layer 55. Through the porous structure on the grate brick 57, the air of the third heat exchange horizontal layer 54 is evenly distributed into the air passage of the transition layer 55, and then enters the combustion interior of the coke oven through the air passage of the transition layer, realizing the uniform distribution of the preheated air.

[0058] Optionally, as Figure 1As shown, the number of air channels and flue gas channels in the heat exchange chamber is the same. They can both be in a single row or multiple rows. Specifically, it can be selected according to the number of combustion chambers of the coke oven and be the same as the number of combustion chambers. The multiple rows of air channels 58 and multiple rows of flue gas channels 59 are arranged alternately by partition walls. For example, it can be determined according to the number of combustion chambers of the coke oven where it is located, such that the lower part of each combustion chamber corresponds to a row of air channels 58 and a row of flue gas channels 59. The air channels 58 and the flue gas channels 59 are arranged side by side, and the air channels 58 and the flue gas channels 59 corresponding to the lower parts of different combustion chambers are arranged alternately, that is, in the heat exchange chamber, they are arranged as "air channel 58 - flue gas channel 59 - air channel 58 - flue gas channel 59".

[0059] Optionally, the partition wall in the heat exchange chamber is made of a material with good high-temperature heat conductivity, such as silica brick. The cross-section of the silica brick is preferably in a T shape, as Figure 5 shown. One end of it extending horizontally is wider, and a groove 60 is provided on the wider end. The other end extending vertically is narrower, and a protrusion 61 matching the groove is provided at the position corresponding to the groove on the narrower end, which is convenient for building the partition wall. The partition wall built with the silica brick with a T-shaped cross-section has an uneven surface, increasing the surface area, which can increase the contact area with air and flue gas and improve the heat transfer effect. The air input from the external environment and the flue gas discharged from combustion transfer heat through the partition wall in each layer structure of the heat exchange chamber to preheat the air, thereby increasing the temperature of the air.

[0060] The heat exchange chamber structure of this embodiment has a simple structure, good heat exchange effect, and a small pressure difference between flue gas and air, and it is not easy to have gas leakage.

[0061] Embodiment 2

[0062] As Figure 2 shown, this embodiment discloses a coke oven, which includes a furnace body. Inside the furnace body, there are a carbonization chamber 10, a combustion chamber 20, and the heat exchange chamber described in Embodiment 1. The carbonization chamber 10 and the combustion chamber 20 are arranged side by side in the upper part of the furnace body. The combustion chamber 20 includes a vertical flue 23 and an air duct 24. The carbonization chamber 10 is communicated with the vertical flue 23. The heat exchange chamber 50 is arranged in the lower part of the furnace body. Its air channel 58 is communicated with the air duct 24 in the combustion chamber 20, and its flue gas channel 59 is communicated with the vertical flue 23 in the combustion chamber 20.

[0063] Optionally, the coke oven further includes a balance channel. The balance channel is arranged at the top of the carbonization chamber 10 and the combustion chamber 20 and is communicated with the carbonization chamber 10 and the combustion chamber 20, and is used to introduce the combustible substances (raw gas) generated by the dry distillation of the coal material in the carbonization chamber 10 into the combustion chamber 20.

[0064] Specifically, the carbonization chamber 10 is used to place coal charge as a site for providing coal charge coking. During the coking process, the lower part of the carbonization chamber 10 is used to place coal charge. After the coal charge is heated and coked, combustible substances (raw gas in this embodiment) are generated. A certain space usually needs to be reserved in its upper part to facilitate the circulation of the raw gas generated by the coking of the coal charge. The coal charge can be high-quality coking coal, or coking coal mixed with weakly caking coal and / or non-caking coal, which is not further limited in this embodiment. The shape of the carbonization chamber 10 is tall and thin, that is, the height is greater than the width, to distinguish it from the traditional horizontal coking furnace. The ratio of the height to the width of the carbonization chamber 10 can be selected according to actual needs, which is not further limited in this embodiment.

[0065] The combustion chamber 20 is adjacent to the carbonization chamber 10, separated by a partition wall (furnace wall), and the two are independent of each other. The combustion chamber 20 is used to receive and burn the combustible substances generated by the coking of the coal charge in the carbonization chamber 10. The heat generated by combustion is then transferred to the carbonization chamber 10 through the partition wall (furnace wall) to provide a heat source for the coking of the coal charge and indirectly heat the carbonization chamber 10. Clay bricks are provided in the area corresponding to the carbonization chamber 10 on the furnace top, and carbon removal holes are left. Corresponding viewing holes are left in the combustion chamber 20. In this embodiment, the partition wall between the carbonization chamber 10 and the combustion chamber 20 is built with silica bricks with good thermal conductivity to improve the heat transfer effect.

[0066] Optionally, the number of carbonization chambers 10 is multiple, and the number of combustion chambers 20 is multiple. The multiple carbonization chambers 10 and the multiple combustion chambers 20 are arranged alternately. The balance channel 30 spans across each carbonization chamber 1 and each combustion chamber 20 to evenly distribute the combustible substances in each carbonization chamber 1 to each combustion chamber 20. The number of combustion chambers 20 is always one more than the number of carbonization chambers 10, so that each carbonization chamber 10 is located between two combustion chambers 20, so as to evenly transfer the heat generated in each combustion chamber 20 to each carbonization chamber 10 and improve the heating uniformity and heating efficiency of the carbonization chamber 10.

[0067] Optionally, as Figure 8 shown, each combustion chamber 20 includes multiple pairs of vertical flues 23. A first partition wall 21 is provided between each pair of vertical flues 23 to make the multiple vertical flues 23 independent of each other, different from the traditional waste gas circulation type vertical flues. The multiple pairs of vertical flues 23 are all vertically arranged, and the top and bottom of the vertical flues 23 are both open. Among them: the top opening of the vertical flue 23 (i.e., the connection hole at the top of the combustion chamber) is used to connect the balance channel 30 to allow the raw gas generated in the carbonization chamber 10 to enter the vertical flue 23. The vertical flue 23 is a combustion channel, and the raw gas burns in the vertical flue 23; the bottom opening of the vertical flue 23 is used to discharge the flue gas generated by the combustion of the raw gas. In this embodiment, the flue gas discharged from the vertical flue 23 first enters the heat exchange chamber 50 to preheat the air input from the external environment, and then enters the waste heat boiler for power generation or steam production, etc.

[0068] In this embodiment, the first partition wall 21 can be built with silica bricks. Each silica brick is provided with a brick groove and a brick tongue. By the mutual engagement between the brick grooves and brick tongues of two adjacent silica bricks, the upper and lower layers of silica bricks can be tightly combined, so as to enhance the strength and stability of the first partition wall 21. At the same time, the first partition wall 21 built with tightly combined silica bricks has good airtightness, which can avoid gas leakage between different vertical flues 23 and between the combustion chamber 20 and the carbonization chamber 10, thereby improving the heating uniformity.

[0069] Optionally, a second partition wall 22 is provided between the two vertical flues 23 in each pair of vertical flues 23. That is to say, the first partition wall 21 and the second partition wall 22 are arranged at intervals, and on both sides of the same vertical flue 23 are a first partition wall 21 and a second partition wall 22 respectively.

[0070] The second partition wall 22 is also built with silica bricks, and an air duct 24 is provided in the second partition wall 22. The number of air ducts 24 in each second partition wall 22 is the same as the number of vertical flues 23 adjacent to the second partition wall 22, that is, two. The two air ducts 24 are respectively communicated with the two vertical flues 23 in each pair of vertical flues, and are used to provide the air required for the combustion of the raw coal gas in the vertical flue 23. That is to say, starting from the outermost vertical flue 23 (i.e., the furnace end) of each combustion chamber 20 for sorting, the air duct 24 is only provided in the partition wall with an odd number (i.e., the second partition wall 22), and no air duct 24 is provided in the partition wall with an even number (i.e., the first partition wall 21). The first partition wall 21 only serves for functions such as load-bearing and isolation.

[0071] During the coking process, since the temperature of the air duct 24 is lower than that of the vertical flue 23, heat will be absorbed from the adjacent vertical flue 23, resulting in temperature differences at different positions in the combustion chamber, that is, the temperatures of the air duct 24 and the vertical flue 23 are different, thus causing differences in the heating degree of the carbonization chamber adjacent to the combustion chamber, and further causing the "zebra stripes" with alternating light and dark arrangements to appear at the positions corresponding to the air duct 24 and the vertical flue 23 on the coking product (i.e., coke), affecting the coke quality. In this embodiment, by only providing the air duct 24 in the partition wall with an odd number (i.e., the second partition wall 22), the number of second partition walls 22 with air ducts 24 can be halved, so as to reduce the number of cold and heat crossovers, which is beneficial to the uniformity of the heating of the carbonization chamber 10, and further reduce or avoid the appearance of "zebra stripes" on the coke, improving the coke quality. Compared with the traditional waste gas circulation type vertical flue, the vertical flues 23 in this embodiment are independent of each other. Since the raw coal gas is introduced into the vertical flues 23 from the top, the flame generated by its combustion is downward, that is, the flame is an inverted flame type, while the air is introduced into the vertical flues 23 in sections from the bottom, so that the inside of the vertical flue 23 is all upward gas flow, and heat can be transferred to the adjacent carbonization chamber 10, which can improve the heat transfer speed and effect and shorten the coking time.

[0072] In this embodiment, an outlet (air outlet 26) is provided on each air duct 24 for inputting air into the flue 23. The number of air outlets 26 is one or more, and preferably, the number of air outlets is multiple.

[0073] Since air is input into the flue 23 from bottom to top and raw coke oven gas is input into the flue 23 from top to bottom, the combustion state in the flue 23 is reverse flame. Therefore, the coke oven in this embodiment is a box-type reverse-flame coke oven. To ensure that the raw coke oven gas is fully burned in the flue 23, as Figure 9 shown, in this embodiment, it is preferred to provide three air outlets 26 on each air duct 24, that is, the air outlet 26 includes a first outlet 261, a second outlet 262, and a third outlet 263, which are sequentially arranged at the upper, middle, and lower parts of the air duct 24. The amount of air input is distributed according to the sizes (areas) of the three air outlets 26. By enabling the raw coke oven gas to burn to different extents in the upper, middle, and lower parts of the flue 23, the temperature uniformity of the combustion chamber 20 can be further improved, and the heating effect on the carbonization chamber 10 can be enhanced. The shapes of the first outlet 261, the second outlet 262, and the third outlet 263 can be any shape such as square or circular, and this embodiment does not make further limitations.

[0074] An alternative embodiment is that the area sizes of the three air outlets 26 are preferably first decreased and then increased from top to bottom, that is, the area size of the second outlet 262 is smaller than that of the first outlet 261, and the area size of the first outlet 261 is smaller than that of the third outlet 263. For example, the area size ratio of the first outlet 261, the second outlet 262, and the third outlet 263 can be 1-2:1:3-5. In this embodiment, the area size ratio of the first outlet 261, the second outlet 262, and the third outlet 263 is preferably 1.5:1:2.5 to ensure that the raw coke oven gas in the upper part of the flue 23 cannot be completely burned. The unburned raw coke oven gas enters the middle part of the flue 23 and continues to burn, and the remaining unburned raw coke oven gas is completely burned in the lower part of the flue 23. This helps to improve the uniformity of the temperature distribution of the entire coke oven.

[0075] In this embodiment, by providing air outlets 26 with different area sizes at different positions on the air duct 24 and inputting air into the upper, middle, and lower parts of the flue 23 in a certain proportion, the unburned raw coke oven gas in the upper part of the flue 23 continues to burn in the middle and lower parts of the flue 23, which can ensure that the raw coke oven gas is completely burned. By inputting air in sections, the uniformity of the temperature of the combustion chamber 20 can be effectively improved, and the damage and softening of the wall between the flues caused by excessive local temperature in the combustion chamber 20 can be avoided.

[0076] It should be noted that the number, position, size, etc. of the above-mentioned air outlets 26 are only partial examples and are not limited thereto. Specifically, they can be adjusted according to the design requirements of the coke oven in this embodiment, and the optimal layout opening plan can be obtained through numerical calculation, which is not further limited here.

[0077] The traditional coke oven adopts a regenerator structure, which preheats both air and raw coke oven gas. Generally, the temperature of the vertical flue 23 can reach 1280°C - 1400°C, which causes greater damage to the wall. In this embodiment, since the regenerator is replaced by a heat exchange chamber, only air is preheated in the heat exchange chamber 50, and the temperature range of the vertical flue 23 is approximately 1100 - 1250°C. It can be seen that the temperature of the vertical flue 23 in this embodiment is lower than that of the vertical flue in the traditional coke oven, so its service life can be extended.

[0078] As Figure 8 shown, considering that the heat dissipation at the furnace end 25 (i.e., the end of the combustion chamber 20 in contact with the outside) is large, in an alternative embodiment, the combustion condition of the vertical flue 23 near the furnace end can also be controlled separately. For example, the size of the outlet of the air duct communicating with the vertical flue 23 near the furnace end 25 can be appropriately increased, or other similar methods can be used to increase the air input to it, accelerate the combustion speed of the raw coke oven gas in the vertical flue 23 near the furnace end 25, and increase the heat generated by combustion to offset its heat dissipation loss.

[0079] In this embodiment, inclined channels 40 are provided at the bottom of the combustion chamber 20 for communicating the combustion chamber 20 and the heat exchange chamber 50. The number of inclined channels 40 is multiple and is the same as the number of vertical flues 23 or air ducts 21. The inclined channel 40 includes a first channel 41 and a second channel 42. As Figure 10 shown, where: both ends of the first channel 41 are respectively communicated with the air duct 21 in the combustion chamber 20 and the air channel 58 in the heat exchange chamber 50 to convey air to the air duct 21; both ends of the second channel 42 are respectively communicated with the vertical flue 23 in the combustion chamber 20 and the flue gas channel 59 in the heat exchange chamber 50 to discharge the flue gas generated by combustion. The first channel 41 and the second channel 42 are separated by silicon bricks with good thermal conductivity for heat exchange between the air in the first channel 41 and the flue gas in the second channel 42. In this embodiment, the inclination of the first channel 41 and the second channel 42 is 30° - 90°, for example, the inclination of the inclined channel 40 can be 40°.

[0080] In this embodiment, the balance channel 30 is arranged in the furnace top and is communicated with each coking chamber 10 and combustion chamber 20 for evenly distributing the combustible substances (raw coke oven gas) generated by the dry distillation of the coal material in the coking chamber 10 to the combustion chamber 20. The balance channel 30 can be built with the above-mentioned silicon bricks and clay bricks. Of course, it can also be built with bricks of other materials, which is not further limited in this embodiment.

[0081] Specifically, as Figure 11 shown, the number of the balance channels 30 is multiple, and the multiple balance channels are arranged in parallel. The top spaces of the coke chambers 10 are used to communicate with each other between the balance channels 30, and the arrangement of the balance channels 30 enables the raw gas of the same coke chamber 10 to enter each balance channel 30 (i.e., horizontal balance); the number of the vertical flues 23 in each combustion chamber 20 is the same, and the number of the balance channels 30 is the same as the number of the vertical flues 23 in a single combustion chamber 20. Each balance channel 30 is communicated with the vertical flues at the corresponding or same positions in each combustion chamber 20. In other words, each balance channel 30 straddles all the coke chambers 10 and all the combustion chambers 20, and is communicated with the coke chamber 10 and the vertical flue 23 at the position directly below it, so that the raw gas in different coke chambers 10 enters each balance channel 30, and the components of the raw gas in each balance channel 30 (the balance channels are not directly communicated with each other, and are only communicated through the coke chambers connected thereto) tend to be consistent. Then, the raw gas in the same balance channel 30 can enter the vertical flues 23 at the same positions in each combustion chamber 20 along the longitudinal direction of the coke oven (i.e., the machine side and coke side directions) (i.e., longitudinal balance), so that the raw gas entering each vertical flue 23 is the same, thereby realizing uniform distribution.

[0082] During the coking process, since different coke chambers 10 are in different coking periods, there are differences in the quantity and composition of the raw gas generated. In this embodiment, each balance channel 30 straddles all the coke chambers 10 and communicates with them, so that under the traction of the pressure difference, the raw gas in the coke chamber 10 with more generated raw gas can enter the balance channel 30 faster and more, and can reach each vertical flue 23 of each combustion chamber 20 through the balance channel 30, enabling the raw gas to be evenly distributed in the balance channel 30. The raw gas can be supplied from the position with more quantity to the position with less quantity, thereby realizing the self-distribution of the raw gas, reducing the differences in the quantity and composition of the raw gas in each vertical flue, making the combustion conditions of each vertical flue closer, and further improving the heating uniformity.

[0083] In the coke oven of this embodiment, the gas flow direction during operation is as follows:

[0084] (1) The coal charge is carbonized in the carbonization chamber, and the raw coke oven gas (650 - 800 °C) is respectively introduced into multiple balance channels at the top of the furnace body through the space reserved at the top of the carbonization chamber, and then enters the vertical flue through the top of the combustion chamber. It burns in the vertical flue, generating a large amount of high-temperature flue gas (about 1300 °C) and heat. The high-temperature flue gas enters the transition layer of the heat exchange chamber through the second channel in the inclined flue at the bottom of the vertical flue, removes a large amount of dust in the transition layer and exchanges heat with the air in this layer. After dust removal, the high-temperature flue gas enters the flue gas channels in the third heat exchange horizontal layer, the second heat exchange horizontal layer, the first heat exchange horizontal layer, and the air cushion layer in sequence through the ash removal waste gas flue, and exchanges heat with the air, so that the air is preheated in the heat exchange chamber and then output to the waste heat boiler for power generation. The heat generated by the combustion of the raw coke oven gas in the vertical flue is transferred to the carbonization chamber arranged between the combustion chambers through heat transfer, which is used for the carbonization of the coal charge. After the coal charge is carbonized, coke products are obtained.

[0085] (2) The cold air in the external environment is input from the bottom of the heat exchange chamber and first enters the air cushion layer to isolate the bottom of the coke oven, which can play a certain protective role; then the air sequentially passes through the air channels in the first heat exchange horizontal layer, the second heat exchange horizontal layer, the third heat exchange horizontal layer, and the transition layer, and exchanges heat with the high-temperature flue gas in the flue gas channels of each layer, thereby increasing its own temperature (about 500 °C); the preheated air enters the air duct in the combustion chamber through the first channel in the inclined flue and enters the vertical flue through the first outlet, the second outlet, and the third outlet arranged on the air duct, which is used for burning the raw coke oven gas.

[0086] For the coke oven of this embodiment, a heat exchange chamber is provided to preheat the air with the high-temperature flue gas generated by the combustion chamber, improving the heat recovery utilization rate. The heat exchange chamber adopts a multi-layer structure design with dual air and flue gas channels, which can improve the heat exchange efficiency.

[0087] It can be understood that the above are only the preferred embodiments of the present invention, and the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also regarded as the protection scope of the present invention.

Claims

1. A coke oven, comprising a furnace body, inside which there are a carbonization chamber (10) and a combustion chamber (20). The combustion chamber includes vertical flues (23) and air flues (24), and the carbonization chamber communicates with the vertical flues. It is characterized in that there is also a heat exchange chamber inside the furnace body. The heat exchange chamber includes a chamber body, the interior of which is a multi-layer structure, and an air passage (58) and a flue gas passage (59) respectively penetrate through each layer of the multi-layer structure, so that the layers of the multi-layer structure are sequentially communicated with each other. The number of the air passages and the flue gas passages are both multiple columns, and the multiple columns of air passages and the multiple columns of flue gas passages are arranged alternately; the air passage is used to communicate with the external environment, and the flue gas passage is used to communicate with the vertical flues of the combustion chamber in the coke oven; the air passage of the heat exchange chamber communicates with the air flue, and the flue gas passage of the heat exchange chamber communicates with the vertical flue; the multi-layer structure includes an air cushion layer (51) and a heat exchange layer. The air cushion layer is arranged at the bottom position inside the chamber body, and the heat exchange layer is arranged above the air cushion layer; a plurality of inlets are provided on the air passage corresponding to the air cushion layer for inputting combustion-supporting gas, and the plurality of inlets are evenly distributed; a plurality of outlets are provided on the flue gas passage in the air cushion layer for discharging flue gas, the plurality of outlets are evenly distributed, and each outlet faces downward; three air outlets (26) are provided on each air flue, and each air outlet is used to input air into the vertical flue. The area sizes of the three air outlets first decrease and then increase from top to bottom, and the area size of the uppermost air outlet is smaller than the area size of the lowermost air outlet; the carbonization chamber and the combustion chamber are arranged side by side at the upper part of the furnace body; the number of the carbonization chambers is multiple, the number of the combustion chambers is multiple, the multiple carbonization chambers and the multiple combustion chambers are arranged alternately, and the number of the combustion chambers is always one more than the number of the carbonization chambers, so that each carbonization chamber is located between two combustion chambers; the coke oven further includes a balance passage (30), which is arranged at the top of the carbonization chamber and the combustion chamber and communicates with the carbonization chamber and the combustion chamber respectively, and is used to evenly distribute the combustible substances generated by the dry distillation of the coal material in the carbonization chamber to the combustion chamber; the number of the balance passages is multiple, the multiple balance passages are arranged in parallel, and the balance passages communicate with each other through the top space of the carbonization chamber, and the arrangement of the balance passages enables the raw gas of the same carbonization chamber to enter each balance passage; the number of the vertical flues in each combustion chamber is the same, the number of the balance passages is the same as the number of the vertical flues in a single combustion chamber, and each balance passage straddles each carbonization chamber and each combustion chamber and communicates with the carbonization chamber and the vertical flue at the position directly below it.

2. The coke oven according to claim 1, It is characterized in that the heat exchange layer includes a first heat exchange horizontal layer (52), a second heat exchange horizontal layer (53) and a third heat exchange horizontal layer (54), which are arranged in sequence from bottom to top. In the first heat exchange horizontal layer, the second heat exchange horizontal layer, and the third heat exchange horizontal layer, the connection points of the air channels corresponding to adjacent two layers are arranged staggeredly, and the connection points of the flue gas channels corresponding to adjacent two layers are arranged staggeredly.

3. The coke oven according to claim 2, wherein, the multi-layer structure further includes a transition layer (55), and the transition layer is arranged above the third heat exchange horizontal layer. In the multi-layer structure, the air channels and the flue gas channels of each layer are separated by partition walls. The flue gas channel corresponding to the transition layer includes a sedimentation area and an ash removal exhaust gas channel (56). The sedimentation area is used for sedimenting the dust in the flue gas from the vertical flue. The ash removal exhaust gas channel is arranged in the partition wall of the transition layer. Its inlet is arranged at the upper part of the transition layer and is communicated with the sedimentation area, and its outlet is communicated with the flue gas channel corresponding to the third heat exchange horizontal layer.

4. The coke oven according to claim 3, wherein, a grid brick (57) is arranged in the air channel corresponding to between the third heat exchange horizontal layer and the transition layer to enable air to enter the transition layer evenly. A grid brick is also arranged in the flue gas channel corresponding to between the third heat exchange horizontal layer and the second heat exchange horizontal layer to enable flue gas to enter the second heat exchange horizontal layer evenly.

5. The coke oven according to any one of claims 1-4, wherein, the number of the air channels is the same as that of the flue gas channels.

6. The coke oven according to claim 5, wherein, a plurality of the air channels and a plurality of the flue gas channels corresponding to each layer are arranged alternately by partition walls, and the partition walls are made of silica bricks. The cross section of the silica brick is in a T shape. A groove is arranged at its wider end, and a protrusion adapted to the groove is arranged at its narrower end.

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