Coking oven and coking system

Abstract

The present invention discloses a coking oven, comprising a furnace body and a furnace top. A carbonization chamber and a combustion chamber are arranged in the furnace body, and the carbonization chamber and the combustion chamber are arranged side by side in the upper part of the furnace body; the coking oven also includes a balancing channel and a heat exchange chamber, the balancing channel is arranged in the furnace top, and is respectively connected with the carbonization chamber and the combustion chamber, and is used to evenly distribute the combustible substances produced by the dry distillation of coal in the carbonization chamber to the combustion chamber; the heat exchange chamber is arranged in the lower part of the furnace body, and is connected with the combustion chamber, and the heat exchange chamber is also connected with the external environment, and is used to preheat the input combustion-supporting gas. The present invention also discloses a coking system, comprising a coking oven and a waste heat boiler, the coking oven adopts the above-mentioned coking oven, and the flue gas channel of the heat exchange chamber is connected to the waste heat boiler. The coking oven of the present invention has more balanced heating, short coking time, low energy consumption and high production capacity.

Description

Technical Field

[0001] The invention belongs to the technical field of coking, and in particular relates to a coking oven and a coking system comprising the coking oven. Background Art

[0002] Coking equipment can recycle chemical byproducts such as tar and ammonia, which is of great significance to the development of the world's steel industry. However, traditional coking equipment will cause serious environmental pollution during the coking process, such as the leakage of smoke and the harmful substances such as benzopyrene it carries. When recycling coking products, a large amount of wastewater will be further generated, which contains harmful substances such as phenol, ammonia, and cyanide, causing great harm to human health and the environment.

[0003] In addition, the world's coal resources, especially high-quality coking coal, are becoming increasingly scarce due to over-exploitation, while the petrochemical and natural gas industries are developing rapidly. Coking products have become alternative products, and coking recovery chemical products have lacked competitiveness.

[0004] In today's world, one of the development directions of coking technology is to make full use of the heat generated in the coking process, such as for power generation or steam production. Heat recovery coke ovens can be used with weakly sticky coal and non-sticky coal for coking. The raw gas and other harmful substances generated in the coking process can be reasonably burned in the coke oven, and the heat of the high-temperature flue gas generated by the combustion can be recovered.

[0005] At present, the heat recovery coke ovens that have been put into scale are mostly ramming coking, hot loading and hot discharge, and have relatively complete coke oven machinery. For example, the Jewell-Thompson non-recovery coke oven technology in the United States has been put into operation in many coking plants in the United States, Australia, Brazil and other countries. my country's heat recovery coke ovens are all ramming coal cake side loading type, and the independently developed furnace structure has four-arch and six-arch horizontal types, which have begun to be used in China, Vietnam, Iran and other countries. These heat recovery coke ovens are mainly horizontal coke ovens, and a few are vertical coke ovens, which have the following shortcomings:

[0006] (1) Horizontal coking oven: The structure occupies a large area and has a high investment cost. The coal cake is 3-4 meters wide. The overly wide carbonization chamber seriously affects the heat transfer effect. The coking time is too long (more than 70 hours). In addition, direct heating is mostly used, and 1.5-4% of the coal and coke will be burned to supplement the heat required for coal distillation, resulting in reduced production capacity.

[0007] (2) Vertical heat recovery coke oven: When the volatile matter of the coking coal is low, the heat required for coal distillation cannot be self-sufficient and additional coal gas is required for supplementary combustion, resulting in low heating efficiency. In addition, since different carbonization chambers are in different coking periods, the amount of raw coal gas produced is different, resulting in uneven heating of the coke oven and a long coking time. Summary of the invention

[0008] The technical problem to be solved by the present invention is to provide a coking furnace and a coking system with balanced heating, short coking time, low energy consumption and high production capacity in view of the above deficiencies in the prior art.

[0009] According to one aspect of the present invention, a coking oven is provided, and its technical solution is as follows:

[0010] A coking oven comprises a furnace body and a furnace top, wherein a carbonization chamber and a combustion chamber are arranged in the furnace body, and the carbonization chamber and the combustion chamber are arranged in parallel at the upper part of the furnace body;

[0011] The coke oven also includes a balance channel and a heat exchange chamber.

[0012] The balance channel is arranged in the furnace top and is connected to the carbonization chamber and the combustion chamber respectively, and is used to introduce the combustible substances generated by the dry distillation of coal in the carbonization chamber into the adjacent combustion chamber;

[0013] The heat exchange chamber is arranged at the lower part of the furnace body and is communicated with the combustion chamber. The heat exchange chamber is also communicated with the external environment and is used for preheating the input combustion-supporting gas.

[0014] Preferably, there are multiple carbonization chambers, there are multiple combustion chambers, and the multiple carbonization chambers and the multiple combustion chambers are arranged alternately, and the balancing channel spans across the carbonization chambers and the combustion chambers to evenly distribute the combustible materials in each carbonization chamber to each combustion chamber.

[0015] Preferably, each of the combustion chambers comprises a plurality of opposing fire channels, and a first partition wall is provided between each of the opposing fire channels.

[0016] Preferably, a second partition wall is provided between the two vertical fire channels of each pair of vertical fire channels, the first partition wall and the second partition wall are spaced apart, and the second partition wall includes two air channels, which are respectively connected to the two vertical fire channels in each pair of vertical fire channels.

[0017] Preferably, there are multiple balancing channels, and the multiple balancing channels are arranged in parallel;

[0018] The number of vertical fire channels in each combustion chamber is the same, and each balancing channel is communicated with the vertical fire channel located directly below it.

[0019] Preferably, a ramp is provided at the bottom of the combustion chamber, and the ramp includes a first channel and a second channel, the first channel is connected to the air channel in the combustion chamber, and the second channel is connected to the vertical fire channel in the combustion chamber.

[0020] Preferably, the inclination of the ramp is 30-90°.

[0021] Preferably, the heat exchange chamber comprises an air channel and a smoke channel, and the two are arranged in parallel, the air channel is connected to the first channel in the ramp, and the smoke channel is connected to the second channel in the ramp.

[0022] Preferably, the heat exchange chamber further comprises a heat exchange chamber body, the interior of the heat exchange chamber body is a multi-layer structure, the air channel and the smoke channel are arranged on the multi-layer structure, so that the layers of the multi-layer structure are connected in sequence.

[0023] According to another aspect of the present invention, a coking system is also provided, and its technical solution is as follows:

[0024] A coking system comprises a coking oven and a waste heat boiler. The coking oven is the coking oven described above, and the flue gas channel of the heat exchange chamber is connected to the waste heat boiler.

[0025] The coking oven provided by the present invention utilizes the heat generated by the combustion of the raw gas generated by the dry distillation of coal materials during the coking process to perform coking. Due to the heat exchange chamber structure, no additional supplementary combustion is required for low-volatile raw coal. The entire system adopts negative pressure operation, which can realize smokeless coal loading, no gas purification and recovery of chemical products. The flue gas generated by the combustion can not only be used to preheat the air input to the coking oven, but also be sent to the waste heat boiler for power generation. Specifically, it has the following beneficial effects:

[0026] (1) Fast heating speed can shorten the coking time.

[0027] Different from the traditional horizontal coking oven, the carbonization chamber of the coking oven of the present invention is arranged to be tall and thin, and the carbonization chamber and the combustion chamber are arranged in parallel, so that the coal cakes placed in the carbonization chamber in a tall and thin shape can absorb the heat transferred by the combustion chamber to be distilled into coke, and the contact area between the carbonization chamber and the combustion chamber is increased, and the air is supplied to the vertical fire channel in sections from bottom to top, which optimizes the uniformity of the temperature field in the vertical fire channel in the high direction (i.e., the vertical direction), and eliminates the crossing holes and circulation holes in the traditional exhaust gas circulation type vertical fire channel, so that the vertical fire channel is full of downflame airflow, which can transfer heat to the adjacent carbonization chamber, thereby improving the heat transfer speed and effect and shortening the coking time.

[0028] (2) Indirect heating is used, which eliminates coal loss and increases production capacity.

[0029] The carbonization chamber and the combustion chamber are arranged in parallel and independently of each other, which avoids the burning loss caused by the ignition of part of the upper coal or coke in the carbonization chamber in the prior art, thereby affecting the coke production capacity. The coke output per ton can be increased by 1.5-4% compared with the horizontal coke oven.

[0030] (3) Heating is more uniform, which can improve the quality and yield of coke.

[0031] By setting a balance channel to evenly distribute the raw gas, the difference in the amount and composition of the raw gas entering the combustion chamber can be reduced, and the difference in the heat generated by combustion in different combustion chambers caused by the fluctuation of the raw gas amount in different carbonization chambers in different coking cycles can be avoided, thereby improving the heating uniformity and further improving the coke quality;

[0032] (4) Replacing chemical recovery with heat recovery simplifies the process flow, reduces floor space, reduces energy consumption, and improves economic efficiency.

[0033] The raw gas produced by coal distillation in the carbonization chamber enters the combustion chamber in a hot state for reasonable combustion. Compared with the chemical recovery process, there is no complicated gas collection, heating and airflow exchange system, complex chemical product recovery and gas purification system, sewage treatment workshop and other processes, which simplifies the process flow, reduces the construction area and cost investment (more than 40%), and is conducive 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 10kWh); the sensible heat generated by combustion is directly transferred to the carbonization chamber through the partition wall (furnace wall) for heating, which can reduce or avoid the additional energy consumption demand of the carbonization chamber. By setting up a heat exchange chamber, the high-temperature flue gas generated in the combustion chamber is heat recovered, which can not only preheat the air, but also send the flue gas after heat exchange to the waste heat boiler for further utilization (such as power generation, steam production, etc.) through the shortest route (the main flue is arranged underground), which can reduce heat loss, realize the cascade utilization of high-temperature flue gas heat, and improve the heat recovery utilization rate.

[0034] (5) Reduces the requirements for coal and saves high-quality coal resources.

[0035] A large amount of weakly sticky coal and a small amount of non-sticky coal can be added to the coal charge, and the proportion can be increased by nearly 50% compared with conventional coke ovens. This saves high-quality coal (coking coal and fat coal) to a certain extent, expands the selection range of coking coal types, and the produced coke has larger size, high carbon content, high strength and low ash content, and the coke quality is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a structural schematic diagram of a coke oven in an embodiment of the present invention;

[0037] Figure 2 is a schematic structural diagram of a combustion chamber in an embodiment of the present invention;

[0038] Figure 3 is a schematic diagram of the distribution of air outlets in an embodiment of the present invention;

[0039] Figure 4 is a schematic structural diagram of a balancing channel in an embodiment of the present invention;

[0040] Figure 5Schematic diagram of the structure of the heat exchange chamber in an embodiment of the present invention;

[0041] Figure 6 is a schematic structural diagram of a ramp in an embodiment of the present invention;

[0042] Figure 7 Schematic diagram of air flow in a coke oven in an embodiment of the present invention;

[0043] Figure 8 Schematic diagram of the direction of flue gas in a coking oven in an embodiment of the present invention;

[0044] Fig. 9 Schematic diagram of the structure of the silicon brick in the embodiment of the present invention;

[0045] Fig.10 This is a schematic diagram of the structure of the air channel in an embodiment of the present invention;

[0046] Fig.11 Schematic diagram of the structure of the smoke channel in an embodiment of the present invention.

[0047] In the figure: 10-carbonization chamber; 20-combustion chamber; 21-first partition wall; 22-second partition wall; 23-vertical fire channel; 24-air channel; 25-furnace end; 26-air outlet; 261-first outlet; 262-second outlet; 263-third outlet; 30-balance channel; 40-inclined channel; 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 channel; 57-grate brick; 58-air channel; 59-smoke channel; 60-groove; 61-protrusion; 62-air inlet; 63-smoke outlet; M-raw gas; F-smoke; K-air. DETAILED DESCRIPTION

[0048] 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 accompanying drawings and specific embodiments of the present invention.

[0049] Aiming at the problems of uneven heating and long coking time in the coking oven in the prior art, the present invention provides a coking oven, comprising a furnace body and a furnace top, wherein a carbonization chamber and a combustion chamber are arranged in parallel in the upper part of the furnace body;

[0050] The coke oven also includes a balance channel and a heat exchange chamber.

[0051] The balance channel is arranged in the furnace top and is connected to the carbonization chamber and the combustion chamber respectively, and is used to introduce the combustible substances generated by the dry distillation of coal in the carbonization chamber into the combustion chamber;

[0052] The heat exchange chamber is arranged at the lower part of the furnace body and is communicated with the combustion chamber. The heat exchange chamber is also communicated with the external environment and is used for preheating the input combustion-supporting gas.

[0053] Accordingly, the present invention also provides a coking system, comprising a coking oven and a waste heat boiler, wherein the coking oven adopts the above-mentioned coking oven.

[0054] Wherein, the flue gas channel of the heat exchange chamber is connected to the waste heat boiler.

[0055] Example 1

[0056] like Figure 1 As shown, this embodiment discloses a coking oven, including a furnace body and a furnace top, wherein a carbonization chamber 10 and a combustion chamber 20 are arranged in the furnace body, wherein: the carbonization chamber 10 and the combustion chamber 20 are built with silicon bricks with good thermal conductivity, and the two are arranged side by side at the upper part of the furnace body.

[0057] The furnace body is also provided with a balance channel 30 and a heat exchange chamber 50. The balance channel 30 is provided in the furnace top, spanning the carbonization chamber 10 and the combustion chamber 20, and is connected with the carbonization chamber 10 and the combustion chamber 20, and is used to introduce the combustible substances produced by the carbonization chamber coal distillation into the combustion chamber; the heat exchange chamber 50 is provided at the lower part of the furnace body, and is connected with the combustion chamber 20, and the heat exchange chamber 50 is also connected with the external environment, and is used to preheat the combustion-supporting gas. The combustion-supporting gas can be air input from the external environment, or a mixed gas of air and coke oven return exhaust gas. In this embodiment, the combustion-supporting gas preferably uses air input from the external environment.

[0058] Specifically, the carbonization chamber 10 is used to place coal material, so as to serve as a place for coal material dry distillation. During the coking process, the carbonization chamber 10 is used to place coal material, and the coal material produces combustible substances (referring to raw coal gas in this embodiment) after being heated and dry distilled. A certain space is usually required at the top to allow the raw coal gas produced by the coal material dry distillation to circulate. The coal material can be high-quality coking coal, or it can be coking coal with weakly sticky coal and / or non-sticky 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 oven. The ratio of the height and width of the carbonization chamber 10 can be selected according to actual needs, which is not further limited in this embodiment. The combustion chamber 20 is located adjacent to the carbonization chamber 10 and is separated by a partition wall (furnace wall). The two are independent of each other. The combustion chamber 20 is used to receive and burn the combustible substances produced by the dry distillation of coal in the carbonization chamber 10. The heat generated by the combustion is then transferred to the carbonization chamber 10, providing a heat source for the dry distillation of coal and indirectly heating 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, and the corresponding combustion chamber 20 has a fire viewing hole.

[0059] Optionally, there are multiple carbonization chambers 10 and multiple combustion chambers 20, and multiple carbonization chambers 10 and multiple combustion chambers 20 are arranged alternately, and the balancing channel 30 spans across each carbonization chamber 10 and the combustion chamber 20, so as to evenly distribute the combustible material in each carbonization chamber 10 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, thereby improving the heating uniformity and heating efficiency of the carbonization chamber 10.

[0060] Optional, such as Figure 2 As shown, each combustion chamber 20 includes a plurality of opposed fire channels 23, and a first partition wall 21 is provided between each opposed fire channel 23, so that the plurality of vertical fire channels 23 are independent of each other, so as to be distinguished from the traditional vertical fire channels of exhaust gas circulation. The plurality of vertical fire channels 23 are all arranged vertically, and the top and bottom of the vertical fire channels 23 are both open, wherein: the top of the vertical fire channel 23 is open (i.e., the connecting hole at the top of the combustion chamber), which is used to connect to the balance channel 30, so that the raw coal gas generated in the carbonization chamber 10 enters the vertical fire channel 23, and the vertical fire channel 23 is a combustion channel, and the raw coal gas burns in the vertical fire channel 23; the bottom of the vertical fire channel 23 is open to discharge the flue gas generated after the raw coal gas is burned. In this embodiment, the high-temperature flue gas discharged from the vertical fire channel first enters the heat exchange chamber 50 to preheat the air input from the external environment, and then enters the waste heat boiler to generate electricity or produce steam, etc.

[0061] In this embodiment, the first partition wall 21 can be built with silica bricks, and each silica brick is provided with a brick groove and a brick tongue. The brick grooves and brick tongues of two adjacent silica bricks are engaged with each other, so that the adjacent silica bricks can be tightly combined 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 fire channels 23 and between the combustion chamber 20 and the carbonization chamber 10, thereby improving the heating uniformity.

[0062] Optionally, a second partition wall 22 is provided between two vertical fire channels in each pair of vertical fire channels 23. That is, the first partition wall 21 and the second partition wall 22 are arranged at intervals, and there are a first partition wall 21 and a second partition wall 22 on both sides of the same vertical fire channel 23, respectively.

[0063] The second partition wall 22 is also built with the above-mentioned 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 fire channels 23 adjacent to the second partition wall, i.e., two, and the two air ducts 24 are respectively connected to the two vertical fire channels 23 in each pair of vertical fire channels, and are used to provide air (combustion-supporting gas) required for the combustion of raw coal gas in the vertical fire channels 23. That is to say, starting from the outermost vertical fire channel 23 (i.e., the furnace end) of each combustion chamber 20, 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), and the first partition wall 21 is only used for bearing, isolation, etc.

[0064] During the coking process, since the temperature of the air duct 24 is lower than that of the vertical fire channel 23, it absorbs heat from the adjacent vertical fire channel 23, resulting in temperature differences at different positions of the combustion chamber, that is, the temperature of the air duct 4 and the vertical fire channel 3 are different, which causes differences in the degree of heating of the carbonization chamber adjacent to the combustion chamber, and thus causes the positions of the coking product (i.e., coke) corresponding to the air duct 24 and the vertical fire channel 23 to appear with alternating light and dark "zebra patterns", affecting the quality of the coke. In this embodiment, by setting the air duct 24 only in the partition wall with an odd serial number (i.e., the second partition wall 22), the number of the second partition wall 22 with the air duct 24 can be halved, thereby reducing the number of cold and hot crossovers in the combustion chamber, which is beneficial to the uniformity of heating of the carbonization chamber 10, thereby reducing or avoiding the appearance of "zebra patterns" on the coke, and improving the quality of the coke.

[0065] Compared with the traditional exhaust gas circulation type vertical fire channel, the vertical fire channels 23 in this embodiment are independent of each other. Since the raw coal gas is introduced into each vertical fire channel 23 from the top, the flame generated by its combustion is downward, that is, the flame is a downflame type, and the air is introduced in sections from the bottom, so that the vertical fire channel 23 is full of rising airflow, which transfers heat to the adjacent carbonization chamber 10, which can improve the heat transfer speed and effect and shorten the coking time.

[0066] In this embodiment, an outlet (i.e., air outlet 26) is provided on each air channel 24 for inputting air into the vertical flue 23. The number of the air outlets 26 is one or more, preferably multiple, and the multiple air outlets 26 are evenly distributed along the length direction of the air channel. The multiple air outlets 26 can allow air to enter each vertical flue 23 from different positions as evenly as possible, so that the raw coal gas can be fully burned in the vertical flue 23 and the temperature balance of the vertical flue is improved, thereby improving the heating effect on the carbonization chamber during coking.

[0067] In this embodiment, since air is input into the vertical fire channel 23 from bottom to top and raw coal gas is input into the vertical fire channel 23 from top to bottom, the combustion state in the vertical fire channel is downdraft. Therefore, the coke oven in this embodiment is a box-type downdraft coke oven.

[0068] like Figure 3 As shown, in order to ensure that the raw coal gas is fully burned in the vertical fire channel 23, in this embodiment, three air outlets 26 are preferably set on each air channel 24, that is, the first outlet 261, the second outlet 262, and the third outlet 263 are sequentially set in the upper, middle, and lower parts of the air channel 24, and the amount of air introduced is distributed according to the size (area) of the three air outlets 26. By making the raw coal gas burn to different degrees in the upper, middle, and lower parts of the vertical fire channel, the temperature of the combustion chamber 20 is made more uniform, and the heating effect of the carbonization chamber 10 can be further improved. The shape of the first outlet 261, the second outlet 262, and the third outlet 263 can be any shape such as square, circular, etc., and this embodiment is not further limited.

[0069] An optional implementation is that the area size of the three air outlets 26 preferably decreases first and then increases from top to bottom, that is, the area size of the second outlet 262 is smaller than the area size of the first outlet, and the area size of the first outlet 261 is smaller than the area size 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, so as to ensure that the raw gas cannot be completely burned in the upper part of the vertical fire channel 23, and the unburned raw gas enters the middle part of the vertical fire channel 23 and continues to burn, and the remaining unburned raw gas is completely burned in the lower part of the vertical fire channel 23, which helps to improve the uniformity of the overall temperature distribution of the coke oven.

[0070] In this embodiment, air outlets 26 of different sizes are provided at different positions on the air duct 24, and air is introduced into the upper, middle and lower parts of the vertical fire duct 23 in a certain proportion, so that the raw coal gas that has not been completely burned in the upper part of the vertical fire duct 23 continues to burn in the middle and lower parts of the vertical fire duct, thereby ensuring that the raw coal gas is completely burned in the combustion chamber. The staged introduction of air can also effectively improve the uniformity of the temperature of the combustion chamber 20, thereby avoiding accelerated damage and softening of the walls between the vertical fire ducts due to excessive local temperature in the combustion chamber 20.

[0071] It should be noted that the number, position, size, etc. of the air outlets 26 listed above are only some examples and are not limited to them. They can be specifically adjusted according to the design requirements of the coke oven in this embodiment, and the optimal opening arrangement scheme can be obtained through numerical calculation, which is not further limited here.

[0072] The conventional coke oven adopts a regenerator structure, which preheats the air and the raw gas at the same time. Generally, the temperature of the vertical flue can reach 1280°C-1400°C, which causes great damage to the wall. In this embodiment, since the regenerator is replaced by a heat exchange chamber, only the air is preheated in the heat exchange chamber 50, so that the temperature range of the vertical flue 23 is about 1100-1250°C. It can be seen that the temperature of the vertical flue 2 in this embodiment is lower than that of the vertical flue in the conventional coke oven, thereby extending its service life.

[0073] like Figure 2 As shown, considering the large heat dissipation of the furnace end 25 (i.e., the end of the combustion chamber 20 in contact with the outside world), in an optional embodiment, the combustion condition of the vertical fire channel 23 near the furnace end can also be controlled separately, for example, the size of the outlet of the air duct connected to the vertical fire channel 23 near the furnace end 25 can be appropriately increased, or other similar methods can be adopted to increase the air input thereto, thereby accelerating the combustion speed of the raw gas in the vertical fire channel 23 near the furnace end 25 and increasing the heat generated by the combustion to offset its heat dissipation loss.

[0074] The balance channel 30 is arranged in the furnace top and communicated with each carbonization chamber 10 and the combustion chamber 20, and is used to evenly distribute the combustible material (raw gas) generated by the dry distillation of the coal in the carbonization chamber 10 to the combustion chamber 20. The balance channel 30 can be built with the above-mentioned silica bricks and clay bricks, and of course can also be built with bricks of other materials, which is not further limited in this embodiment.

[0075] Specifically, Figure 4 As shown, there are multiple balancing channels 30, which are arranged in parallel. The balancing channels 30 are interconnected through the top space of the carbonization chamber 10, and the arrangement of the balancing channels 30 allows the raw coal gas of the same carbonization chamber 10 to enter each balancing channel 30 (i.e., horizontal balance); the number of vertical fire channels 23 in each combustion chamber 20 is the same, and the number of balancing channels 30 is the same as the number of vertical fire channels 23 in a single combustion chamber 20. Each balancing channel 30 is connected to the vertical fire channels at the corresponding position or the same position in each combustion chamber 20, or in other words, each balancing channel 30 spans across each carbonization chamber. 10 and each combustion chamber 20, and connected with the carbonization chamber 10 and the vertical fire channel 23 located directly below it, so that the raw coal gas in different carbonization chambers 10 can enter into each balancing channel 30, so that the raw coal gas composition in each balancing channel (the balancing channels are not directly connected to each other, and are only connected through the carbonization chambers connected to them) tends to be consistent, and then the raw coal gas in the same balancing channel 30 can enter into the vertical fire channel 23 at the same position in each combustion chamber 20 along the longitudinal direction of the coke oven (i.e. the coke side direction) (i.e. longitudinal balance), so that the raw coal gas entering each vertical fire channel 23 is the same, thereby achieving uniform distribution.

[0076] During the coking process, since different carbonization chambers 10 are in different coking periods, the amount and composition of the raw coal gas produced are different. In this embodiment, each balancing channel 30 spans all the carbonization chambers 10 and is connected thereto, so that the raw coal gas of multiple carbonization chambers 10 in different coking periods can enter the balancing channel 30 faster and more quickly under the traction of the pressure difference, and can reach each vertical fire channel 23 of each combustion chamber 20 through the balancing channel 30, so that the raw coal gas is evenly distributed in the balancing channel 30, and the raw coal gas can be supplied from the position with more amount to the position with less amount, thereby realizing the autonomous distribution of the raw coal gas, reducing the difference in the amount and composition of the raw coal gas of each vertical fire channel, making the combustion conditions of each vertical fire channel closer, and thus improving the heating uniformity.

[0077] The heat exchange chamber 50 is arranged at the lower part of the furnace body and is connected to the lower part of the combustion chamber 20. The heat exchange chamber 50 is also connected to the external environment. The (high temperature) flue gas generated by the combustion of the combustible material in the combustion chamber 20 enters the heat exchange chamber 50. Since the flue gas contains a large amount of heat, it can be used to preheat the air input from the external environment. The outer wall of the heat exchange chamber 50 is preferably built with bricks made of materials with good thermal insulation to reduce heat loss.

[0078] Specifically, Figure 5 As shown, the heat exchange chamber 50 includes an air channel 58 and a smoke channel 59, which are arranged in parallel, wherein: the air channel 58 is connected to the air channel 24 in the combustion chamber 20, and is used to transport air to the air channel 24; the smoke channel 59 is used to connect to the vertical fire channel 23 in the combustion chamber 20, and is used to output the high-temperature smoke generated after combustion in the vertical fire channel 23. The number of air channels 58 and smoke channels 59 is the same as the number of combustion chambers 20, both of which are multiple, that is, the lower part of each combustion chamber 20 corresponds to an air channel 58 and a smoke channel 59, and the air channels 58 and smoke channels 59 corresponding to the lower parts of different combustion chambers 20 are arranged alternately, that is, the heat exchange chamber 50 is arranged according to "air channel 58-smoke channel 59-air channel 58-smoke channel 59".

[0079] like Figure 6 As shown, a ramp 4 is provided at the bottom of the combustion chamber 20 for connecting the combustion chamber 20 and the heat exchange chamber 50. The number of the ramps 4 is multiple and the same as the number of the vertical fire channel 23 or the air channel 24. The ramp 4 includes a first channel 41 and a second channel 42, wherein: the two ends of the first channel 41 are respectively connected to the air channel 24 in the combustion chamber 20 and the air channel 58 of the heat exchange chamber 50, so as to transport air to the air channel 24; the two ends of the second channel 42 are respectively connected to the vertical fire channel 23 in the combustion chamber 5 and the smoke channel 59 of the heat exchange chamber 50, so as to discharge the smoke generated by combustion.

[0080] The first channel 41 and the second channel 42 are separated by silica bricks with good thermal conductivity so as to exchange heat 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° to 90°, for example, the inclination of the ramp 4 can be 40°.

[0081] The heat exchange chamber 50 includes a heat exchange chamber body, and the interior of the heat exchange chamber body is divided into a multi-layer structure. Each layer in the multi-layer structure has an air channel and a smoke channel. The air channels of all layers are connected to form a whole row of air channels 58, and the smoke channels of all layers are connected to form a whole row of smoke channels 59. The air channels and smoke channels of the layer are separated by setting a partition wall. In other words, the air channels 58 and the smoke channels 59 are arranged in parallel and penetrate the multi-layer structure so that the layers of the multi-layer structure are connected in sequence. In this embodiment, the air channels of each layer of the heat exchange chamber are connected in sequence, and the smoke channels of each layer are connected in sequence, and finally an S-shaped air channel 58 and an S-shaped smoke channel 59 are formed, so that the air (combustion-supporting gas) flows upward from bottom to top in the air channel 58 layer by layer (such as Figure 7 As shown in FIG. 1 , the flue gas flows downward in a circuitous manner layer by layer from top to bottom in the flue gas channel 59 (as shown in FIG. 1 ). Figure 8 As shown), the heat exchange time can be extended and the heat exchange contact area can be increased to improve the heat exchange effect.

[0082] The partition wall in the heat exchange chamber 50 is made of a material having good high temperature resistance and thermal conductivity, such as silica bricks. The cross-sectional shape of the silica bricks is preferably T-shaped. Fig. 9 As shown, one end extending horizontally is wider and is provided with a groove 60, while the other end extending vertically is narrower and is provided with a protrusion 61 matching the groove 60 at the position corresponding to the groove, so as to facilitate the construction of partition walls. The partition wall constructed with silicon bricks having a T-shaped cross section has an uneven surface, which increases its surface area, increases the contact area with air and flue gas, and improves the heat transfer effect. The air input from the external environment and the high-temperature flue gas discharged from the combustion chamber after combustion are heat exchanged through the partition wall in each layer structure of the heat exchange chamber 50, so as to transfer heat to preheat the air in the air channel 58, thereby increasing the temperature of the air. In this embodiment, the preheating temperature of the air in the heat exchange chamber 50 is 400-600°C, for example, about 500°C. The specific number of layers of the heat exchange chamber 50 can be selected according to actual conditions, and this embodiment is not further limited.

[0083] In this embodiment, Figure 1 , Figure 4As shown, the multi-layer structure of the heat exchange chamber 50 includes an air cushion layer 51 and a heat exchange layer, wherein: the air cushion layer 51 is arranged at the bottom position inside the heat exchange chamber body, and the heat exchange layer is arranged on the upper part of the air cushion layer 51. In some optional 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, which are arranged from bottom to top and interconnected, and the connecting parts of any two adjacent layers (including the upper and lower connecting parts of the air channels of each layer and the upper and lower connecting parts of the smoke channels) are staggered, and finally form an S-shaped air channel 58 and an S-shaped smoke channel 59, and the air (combustion-supporting gas) flows upward from bottom to top layer by layer, and the smoke flows downward from top to bottom layer by layer, thereby extending the heat exchange time and increasing the heat exchange contact area to improve the heat exchange effect.

[0084] Among them, the number of air channels 58 and smoke channels 59 penetrating the multi-layer structure can be one or more rows. In this embodiment, the air channels 58 and smoke channels 59 are multiple rows, so the number of air channels and smoke channels in each layer is multiple, and the air channels of each layer and the smoke channels of each layer are arranged alternately. The part of the smoke channel 59 between the second heat exchange horizontal layer 53 and the third heat exchange horizontal layer 54 is provided with a grate brick 57. Through the porous structure on the grate brick 57, the high-temperature smoke of the third heat exchange horizontal layer 54 can be evenly dispersed and input into the second heat exchange horizontal layer 53, which is conducive to improving the uniformity of air preheating.

[0085] Corresponding to each air channel in the air cushion layer 51, a plurality of air inlets are provided. In this embodiment, preferably, four air inlets 62 are provided on each air channel. Fig.10 As shown, the four air inlets 62 are evenly distributed so that air can enter the heat exchange chamber 50 evenly. The air cushion layer 51 is the first layer for cold air from the outside environment to enter the furnace body, which can isolate and block the heat transfer from the first heat exchange horizontal layer 52, cool the bottom of the coke oven, and protect the bottom of the coke oven. Each smoke channel of the air cushion layer 51 is provided with a plurality of smoke outlets for discharging smoke generated by combustion in the vertical fire channel. In this embodiment, four smoke outlets 63 are preferably provided on each smoke channel, such as Fig.11 As shown, four smoke outlets 63 form a four-part smoke channel. Optionally, a reserved smoke channel opening can be provided on the smoke channel in the air cushion layer, which does not circulate smoke when the heat exchange chamber is in normal use and is used for backup.

[0086] In this embodiment, the heat exchange chamber 50 adopts a four-part heat exchange chamber, that is, each air channel is provided with four air inlets and each smoke channel is provided with four smoke outlets, which converts the original long paths of each layer in series into four short paths in parallel, thereby shortening the air and smoke circulation paths and reducing the circulation resistance, thereby reducing their respective pressure drops and reducing the pressure difference between the two, thereby reducing the risk of air and smoke leakage in the heat exchange chamber 50 (there are certain gaps in the partition walls made of silicon bricks, and these gaps will cause gas leakage between the brick walls in the furnace. After adopting the four-part heat exchange chamber, the pressure difference between the air channel and the smoke channel is reduced, and the leakage phenomenon is weakened), which can improve the stability and reliability of the heat exchange chamber 50.

[0087] In this embodiment, since the coke oven is in a negative pressure state, during the process of coal loading, the external smoke and dust will enter the combustion chamber 20, and the raw coal gas generated during the coking process will also carry some ash, resulting in a large amount of dust in the high-temperature smoke discharged from the combustion chamber 20. Therefore, in this embodiment, Figure 1 As shown, a transition layer 55 may be further provided in the heat exchange chamber 50. The transition layer 55 is provided above the third heat exchange horizontal layer and between the third heat exchange horizontal layer 54 and the bottom of the combustion chamber 20. The transition layer 55 is also provided with a partition wall, which is divided into an air channel and a smoke channel through the partition wall. The air channel of the transition layer is connected to the air channel of the third heat exchange horizontal layer 54, and the smoke channel of the transition layer includes a settling area and an ash removal exhaust gas channel 56 provided in the partition wall. The inlet of the settling area is connected to the vertical fire channel 23 of the combustion chamber 20. The inlet of the ash removal exhaust gas channel 56 is preferably provided at the upper part of the smoke channel of the transition layer 55 and is connected to the settling area. The outlet of the ash removal exhaust gas channel 56 is connected to the smoke channel provided in the third heat exchange horizontal layer 54. The dust in the smoke coming out of the combustion chamber settles in the settling area due to gravity, and the dust deposited in the settling area is cleaned at regular intervals to maintain the ash removal effect of the transition layer 55. The flue gas after ash removal enters the flue gas channel of the third heat exchange horizontal layer 54 from the ash removal exhaust gas channel 56. The part of the air channel between the third heat exchange horizontal layer 54 and the transition layer 55 is also provided with a grate brick 57. Through the porous structure on the grate brick 57, the low-temperature air of the third heat exchange horizontal layer 54 is evenly dispersed and input to the transition layer 55, which is conducive to improving the uniformity of air preheating.

[0088] The coking oven in this embodiment has the following airflow directions during operation:

[0089] (1) Coal is carbonized in the carbonization chamber 10, and the raw coal gas (650-800°C) is generated. It enters the multiple balance channels 30 at the top of the furnace body through the space reserved at the top of the carbonization chamber, and then enters the vertical fire channel 23 from the top of the combustion chamber 20. It burns in the vertical fire channel 23, generating a large amount of high-temperature flue gas (about 1300°C) and heat. Figure 8As shown, the high-temperature flue gas enters the transition layer 55 of the heat exchange chamber 50 from the bottom of the vertical flue 23 through the second channel 42 in the ramp 40, removes a large amount of dust in the transition layer 55 and exchanges heat with the air (combustion-supporting gas) in the layer, and the high-temperature flue gas after ash removal enters the flue gas channels in the third heat exchange horizontal layer 54, the second heat exchange horizontal layer 53, the first heat exchange horizontal layer 52, and the air cushion layer 51 in turn through the ash removal exhaust gas channel 56, and exchanges heat with the air in the air channels in the above layers, so that the air is preheated in the heat exchange chamber 50, and then output to the waste heat boiler for power generation. The heat generated by the combustion of the raw coal gas in the vertical flue 23 is transferred to the carbonization chamber 10 set between the combustion chambers 20 through heat transfer, which is used for coal dry distillation, and the coke product is obtained after the coal dry distillation.

[0090] (2) Figure 7 As shown, the cold air (combustion-supporting gas) from the outside environment is input from the bottom of the heat exchange chamber 50 and first enters the air cushion layer 51, thereby isolating the bottom of the coke oven and playing a certain protective role; then the air passes through the air channels in the first heat exchange horizontal layer 52, the second heat exchange horizontal layer 53, the third heat exchange horizontal layer 54, and the transition layer 55 in turn, 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 channel 24 in the combustion chamber from the first channel 41 in the inclined channel, and then enters the vertical fire channel through the first outlet, the second outlet, and the third outlet set on the air channel 24, for burning raw coal gas.

[0091] The coking oven disclosed in this embodiment is a box-type downdraft coking oven, which performs coking by utilizing the heat generated by the combustion of raw coal gas produced by the dry distillation of coal during the coking process, and realizes smokeless coal loading through negative pressure operation, without the need for additional post-combustion, gas purification, and recovery of chemical products. The flue gas generated by the combustion can be used to preheat the air input to the coking oven, and can then be sent to the waste heat boiler for further heat recovery.

[0092] Example 2

[0093] The present embodiment discloses a coking system, including a coking oven and a waste heat boiler, wherein the coking oven adopts the coking oven described in Example 1, and the flue gas channel in the heat exchange chamber of the coking oven is connected with the waste heat boiler. Specifically, the flue gas outlets 63 are arranged on each flue gas channel in the air cushion layer 51 in the heat exchange chamber 50 to be connected with the waste heat boiler. The high-temperature flue gas generated by the combustion chamber is cooled down after heat exchange with the air in the heat exchange chamber, and then is introduced into the waste heat boiler for power generation or steam production, etc.

[0094] The coking system of this embodiment can utilize the heat of high-temperature flue gas generated during the coking process in a cascade manner, thereby improving the heat recovery rate.

[0095] It is to be understood that the above is only a preferred embodiment of the present invention, but the present invention is not limited thereto. For those skilled 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 considered as the protection scope of the present invention.

Claims

1. A coking oven, comprising a furnace body and a furnace top, wherein a carbonization chamber (10) and a combustion chamber (20) are provided in the furnace body, It is characterized in that The carbonization chamber and the combustion chamber are arranged in parallel at the upper part of the furnace body; The coke oven further comprises a balance channel (30) and a heat exchange chamber (50). The balance channel is arranged in the furnace top and is connected to the carbonization chamber and the combustion chamber respectively, and is used to introduce the combustible substances generated by the dry distillation of coal in the carbonization chamber into the adjacent combustion chamber; The heat exchange chamber is arranged at the lower part of the furnace body and is connected to the combustion chamber. The heat exchange chamber is also connected to the external environment and is used to preheat the input combustion-supporting gas; The heat exchange chamber further comprises a heat exchange chamber body, the interior of the heat exchange chamber body is a multi-layer structure, and the multi-layer structure of the heat exchange chamber comprises an air cushion layer and a heat exchange layer, wherein: the air cushion layer is arranged at the bottom position of the interior of the heat exchange chamber body, and the heat exchange layer is arranged on the upper part of the air cushion layer; The heat exchange chamber comprises an air channel (58) and a smoke channel (59), wherein the air channel and the smoke channel are arranged on the multi-layer structure so that the layers of the multi-layer structure are connected in sequence; A plurality of air inlets are provided on each air channel in the air cushion layer, and a plurality of smoke outlets are provided on each smoke channel in the air cushion layer, and each of the smoke outlets faces downward; There are multiple carbonization chambers, there are multiple combustion chambers, and the multiple carbonization chambers and the multiple combustion chambers are arranged alternately. The balancing channel spans across the carbonization chambers and the combustion chambers to evenly distribute the combustible materials in the carbonization chambers to the combustion chambers. There are multiple balancing channels, which are arranged in parallel. The balancing channels are interconnected through the top space of the carbonization chamber, and the arrangement of the balancing channels allows the raw coal gas in the same carbonization chamber to enter each balancing channel. Each of the combustion chambers comprises a plurality of vertical fire channels (23), the number of vertical fire channels in each combustion chamber is the same, the number of the balancing channels is the same as the number of the vertical fire channels in a single combustion chamber, and each balancing channel is connected to the vertical fire channel located directly below it; Three air outlets (26) are provided on each of the air ducts, each of the air outlets is used to input air into the vertical fire duct, and the multiple air outlets are evenly distributed along the length direction of the air duct. The area size of the three air outlets decreases first and then increases from top to bottom, and the area size of the uppermost air outlet is smaller than the area size of the lowermost air outlet.

2. The coking oven according to claim 1, It is characterized in that A first partition wall (21) is provided between each of the opposing fire channels.

3. The coking oven according to claim 2, It is characterized in that A second partition wall (22) is provided between the two vertical fire paths of each pair of vertical fire paths, and the first partition wall and the second partition wall are spaced apart from each other. The second partition wall includes two air passages (24), which are respectively connected to two vertical fire passages in each pair of vertical fire passages.

4. The coking oven according to claim 3, It is characterized in that The bottom of the combustion chamber is provided with a ramp (40), the ramp comprising a first channel and a second channel. The first passage is communicated with an air passage in the combustion chamber, and the second passage is communicated with a vertical fire passage in the combustion chamber.

5. The coking oven according to claim 4, It is characterized in that The inclination of the ramp is 30-90°.

6. The coking oven according to claim 4, It is characterized in that The air channel (58) and the smoke channel (59) are arranged in parallel, the air channel is communicated with the first channel in the ramp, and the smoke channel is communicated with the second channel in the ramp.

7. A coking system comprising a coking oven and a waste heat boiler, It is characterized in that The coking oven is the coking oven according to any one of claims 1 to 6, The flue gas channel of the heat exchange chamber is connected to the waste heat boiler.

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