Lean gas downward spraying type coke oven structure

Abstract

The utility model relates to a lean gas downward spraying type coke oven structure which comprises a heat storage chamber and a lean gas downward spraying system, the heat storage chamber is a cellular heat storage chamber; the lean gas downward spraying system consists of a lean gas main pipe, a lean gas branch pipe, a lean gas transverse pipe and lean gas downward spraying pipes which are connected in sequence; the lean gas downward spraying pipes are arranged in one-to-one correspondence with the partitioned regenerative chambers; the lean gas lower spray pipe is composed of a lower spray pipe upper pipe and a lower spray pipe lower pipe. The lean gas is supplied into the cellular regenerative chamber through the lean gas lower spray pipe, so that the independent control of the lean gas quantity supplied into the vertical flue is realized; a gas flow distribution device is arranged at the top of the lean gas lower spray pipe to ensure that lean gas is uniformly distributed in checker bricks after entering the heat storage chamber; the lean gas lower spray pipe adopts an upper-lower two-section structure, and a horn mouth structure is arranged at the middle joint, so that the influence of thermal expansion of the coke oven on the structural stability of the lean gas lower spray pipe is prevented.

Description

Technical Field

[0001] The utility model relates to the technical field of coke oven coking, in particular to a structure of a lean gas bottom-injection coke oven. Background Technique

[0002] The coking industry is an important part of China's iron and steel industry, and the coke oven is the most important thermal equipment among them. In the coke oven, the combustion chambers and the carbonization chambers are arranged alternately. The gas burns in the vertical flues of the combustion chamber to provide heat for the coal dry distillation in the carbonization chamber. Each combustion chamber consists of several pairs of double-connected flues. The uniformity of the vertical flue temperature directly affects the uniformity of the longitudinal heating of the coke cake. The uniformity of the vertical flue temperature in the combustion chamber is generally represented by the horizontal row temperature curve. Due to the large heat dissipation of the furnace head flues in the combustion chamber and problems such as air leakage in the regenerator sealing wall, the temperature of the furnace head flues is generally lower than that of the middle flues, which will seriously affect the maturity of the furnace head coke in the carbonization chamber, resulting in problems such as smoke and fire during coke pushing or even difficult coke pushing.

[0003] Modern large coke ovens generally adopt a regenerator grid division, coke oven gas bottom-injection, and lean gas and air side-inlet double-heating coke oven structure. When using coke oven gas for heating, the heating gas volume of each vertical flue can be adjusted separately by a gas regulating device, which is convenient for adjustment. The horizontal row temperature in the combustion chamber is generally relatively uniform, and the temperature of the furnace head flues generally can also meet the production requirements. When using lean gas for heating, the lean gas is supplied from the side of the small flue. After being distributed by the grid bricks, it enters each grid of the regenerator respectively, is preheated by the checker bricks and then enters the vertical flue for heating. The gas volume entering the vertical flue is adjusted by the regulating bricks on the grid bricks. Since the gas volumes entering each grid of the regenerator will affect each other, when adjusting the gas volume of a certain vertical flue, all the regulating bricks of the corresponding gas regenerator need to be repeatedly verified and adjusted, resulting in a huge amount of adjustment work. Moreover, when using lean gas for heating, the waste gas volume in the vertical flue is large, and more heat is carried away by the furnace head flues. Due to factors such as the limitation of the grid bricks and the mutual influence of the gas volumes supplied to the grid regenerators from the small flues, the gas supply volume of the furnace head flues is relatively insufficient, resulting in a lower temperature of the furnace head flues, which affects the maturity of the furnace head coke cake and the normal production of the coke oven.

[0004] In addition, gas with a low calorific value is not easy to burn. The calorific value of lean gas is generally 3000 - 4000 kJ / Nm 3 , and it needs to be preheated before entering the vertical flue for heating and combustion. Otherwise, it will affect the thermal effect of combustion, and the vertical flue temperature will not reach the heating requirements. If the lean gas is ejected at a very high speed and enters the checker bricks for preheating, there is no gas flow around the checker bricks far from the ejection port, which will seriously affect the utilization rate of the checker bricks and the preheating effect of the lean gas. Summary of the Invention

[0005] The utility model provides a lean gas down-spray coke oven structure, which supplies lean gas into the divided regenerator through a lean gas down-spray pipe to realize the individual control of the amount of lean gas supplied into the vertical flue; an air flow distribution device is arranged at the top of the lean gas down-spray pipe to ensure the uniform distribution of lean gas in the checker bricks after entering the regenerator; the lean gas down-spray pipe adopts an upper and lower two-stage structure, and a bell mouth structure is arranged at the middle connection to prevent the thermal expansion of the coke oven from affecting the structural stability of the lean gas down-spray pipe.

[0006] In order to achieve the above object, the utility model is realized by adopting the following technical solutions:

[0007] A lean gas down-spray coke oven structure includes a carbonization chamber, a combustion chamber and a regenerator; it also includes a lean gas down-spray system; the regenerator is a divided regenerator; the lean gas down-spray system is composed of a lean gas main pipe, a lean gas branch pipe, a lean gas cross pipe and a lean gas down-spray pipe connected in sequence, and the lean gas down-spray pipe is arranged corresponding to each divided regenerator; the lean gas down-spray pipe is composed of an upper down-spray pipe and a lower down-spray pipe; the lower end of the lower down-spray pipe is connected to the lean gas cross pipe, the upper end of the lower down-spray pipe penetrates upward from the foundation roof slab of the coke oven, and a gas flow regulating device is arranged on the lower down-spray pipe; a bell mouth structure is arranged at the lower end of the upper down-spray pipe and is movably connected to the lower down-spray pipe, the upper end of the upper down-spray pipe penetrates upward from the corresponding small flue and checker brick, and an air flow distribution device is arranged at the top end of the upper down-spray pipe.

[0008] Further, the bell mouth structure is arranged in the paving brick of the small flue.

[0009] Further, the air flow distribution device is arranged at the top of the checker brick and the bottom of the checker brick.

[0010] Further, the air flow distribution device is an air flow distribution cylinder, which is arranged along the machine side-coke side direction, and air holes are respectively arranged on both sides of the air flow distribution cylinder.

[0011] Further, the air flow distribution device is an air flow distribution cone, which is arranged along the machine side-coke side direction, and the width of the upper opening of the air flow distribution cone is greater than the width of the lower opening.

[0012] Further, the lower down-spray pipe is a metal pipe, and the upper edge of the lower down-spray pipe is 5-20 mm higher than the top surface of the paving brick of the regenerator.

[0013] Further, the upper down-spray pipe is a heat-resistant stainless steel pipe with a wall thickness of 3-8 mm.

[0014] Further, the upper down-spray pipe is built by refractory bricks, and the refractory bricks are built by an inlay structure.

[0015] Compared with the prior art, the beneficial effects of the utility model are:

[0016] (1) By changing the feeding mode of lean gas to the bottom injection type, the individual regulation of the lean gas volume entering the vertical flue is realized, which is simple and efficient. It can effectively regulate the temperature of the vertical flue in the combustion chamber, optimize the heating uniformity of the coke cake in the longitudinal direction, and solve the problems of the huge adjustment workload of the checker bricks in the regenerator and the difficulty in adjusting the heating uniformity in the longitudinal direction of the combustion chamber when the lean gas was fed from the side before. Especially, the gas volume of the furnace head flue can be individually regulated, with a large gas volume adjustment range, effectively increasing the temperature of the furnace head flue, accelerating the maturation speed of the coke cake at the furnace head, reducing the coking time, saving gas volume, and reducing the phenomena of smoke and fire during coke pushing and difficult coke pushing.

[0017] (2) An air flow distribution device is arranged at the top of the bottom injection pipe, which can make the lean gas coming out of the bottom injection pipe evenly distributed in the lower checker bricks, improve the utilization rate of the checker bricks and the thermal efficiency of the regenerator, and save energy and reduce emissions.

[0018] (3) The bottom injection pipe is divided into upper and lower parts, and a bell mouth structure is arranged in the middle, which solves the problem of inconsistent displacement between the upper and lower parts of the bottom injection pipe during the thermal expansion of the coke oven, and improves the structural stability of the bottom injection pipe. At the same time, different materials can be used for the upper pipe and the lower pipe according to different working environments, reducing equipment investment and increasing its service life. Brief Description of the Drawings

[0019] Figure 1 It is a schematic diagram of the structure of a lean gas bottom injection type coke oven described in the present utility model.

[0020] Figure 2 is Figure 1 the left view of

[0021] Figure 3 It is a partial schematic diagram of the structure of the lean gas bottom injection type coke oven in Embodiment 1 of the present utility model.

[0022] Figure 4 It is a partial schematic diagram of the structure of the lean gas bottom injection type coke oven in Embodiment 2 of the present utility model.

[0023] In the figure: 1. Lean gas bottom injection system 11. Lean gas main pipe 12. Lean gas branch pipe 13. Lean gas cross pipe 14. Lean gas bottom injection pipe 141. Lower pipe of the bottom injection pipe 142. Bell mouth structure 143. Upper pipe of the bottom injection pipe 144. Air flow distribution device 15. Gas flow regulating device 16. Regulating cock 17. Orifice box 18. Switching cock 2. Regenerator 21. Foundation roof plate 22. Small flue 23. Checker bricks 24. Checker bricks 25. Bottom paving brick of the small flue 3. Inclined flue 4. Combustion chamber Detailed Embodiments

[0024] The following further describes the detailed embodiments of the present utility model with reference to the drawings:

[0025] Such as Figure 1 、Figure 2 As shown in the figure, for the structure of a lean gas down-spray coke oven of the present utility model, the coke oven includes a carbonization chamber, a combustion chamber 4, an inclined flue 3, a regenerator 2, a furnace top, etc.; the regenerator 2 of the coke oven is a grid-type regenerator, and the lean gas down-spray system 1 includes a lean gas main pipe 11, lean gas branch pipes 12, lean gas cross pipes 13, lean gas down-spray pipes 14, and a gas flow regulating device 15. A control valve is provided on the lean gas main pipe 11, and an adjusting plug 16, an orifice box 17, and a change-over plug 18 are provided on the lean gas branch pipe. The adjusting plug 16 and the orifice box 17 are used to adjust the gas volume entering the lean gas cross pipe, and the change-over plug is used to control the opening and closing of the gas passage; the lean gas down-spray pipe 14 of the lean gas branch pipe is arranged directly below the regenerator 2 and is composed of a lower pipe 141 of the down-spray pipe and an upper pipe 143 of the down-spray pipe. Each grid of the regenerator corresponds to a group of lean gas down-spray pipes 14. The lower pipe 141 of the down-spray pipe is embedded in the foundation roof slab 21 of the coke oven, and the upper pipe 143 of the down-spray pipe passes through the small flue 22 and is connected to the grid brick 23 and the corresponding regenerator 2; a bell mouth structure 142 is provided at the bottom of the upper pipe 143 of the down-spray pipe and is connected to the lower pipe 141 of the down-spray pipe, and an air flow distribution device 144 is provided at the top of the upper pipe 143 of the down-spray pipe.

[0026] The bell mouth structure 14 is arranged at the lower end of the upper pipe 143 of the down-spray pipe and within the bottom paving brick 25 of the small flue. The lean gas down-spray pipe 14 is installed during the cold-state masonry of the coke oven. During installation, the center of the lower pipe 141 of the down-spray pipe at the center position of the coke oven coincides with the center of the corresponding upper pipe 143 of the down-spray pipe. However, in the direction from the center of the coke oven to the machine side and from the center of the coke oven to the coke side, the centers of the lower pipe 141 of the down-spray pipe and the corresponding upper pipe 143 of the down-spray pipe are offset, and the offset distance is greater the farther away from the center of the coke oven, but it is necessary to ensure that the outlet of the lower pipe 141 of the down-spray pipe is always within the bell mouth structure 142.

[0027] The lower pipe 141 of the down-spray pipe is made of a metal pipe, and a gas flow regulating device 15 is provided thereon to control the gas volume in each lean gas down-spray pipe 14; the upper edge of the lower pipe 141 of the down-spray pipe is 5 - 20 mm higher than the top surface of the regenerator paving brick.

[0028] The air flow distribution device 144 provided at the top of the upper pipe 143 of the down-spray pipe is located between the checker brick 24 and the grid brick 23. It can adopt an air flow distribution cylinder with holes on both sides, which is arranged horizontally along the regenerator, and air holes are evenly opened on both sides of the air flow distribution cylinder. The air flow distribution device 144 can also adopt an air flow distribution cone with an upward-opening and expanding shape.

[0029] The upper pipe 143 of the down-spray pipe can be made of a heat-resistant stainless steel pipe with a wall thickness of 3 - 8 mm, or it can be made of refractory materials such as pipe bricks. The pipe bricks are laid in an inlaid structure to ensure its airtightness and structural stability.

[0030] The regenerator 2 of the coke oven is composed of a gas regenerator and an air regenerator arranged alternately. The lean gas horizontal pipe 13 and the lean gas down-spray pipe 14 are only arranged directly below the gas regenerator. The regenerator 2 is a grid-type regenerator, and each grid of the grid-type regenerator corresponds to a group of lean gas down-spray pipes 14. The small flue 22 and the grid brick 23 are connected to the corresponding regenerator grid, so that the lean gas sprayed out from the lean gas down-spray pipe 14 can directly enter the corresponding regenerator grid.

[0031] A gas flow regulating device 15 is arranged on the lower pipe 141 of the down-spray pipe to control the gas volume entering each regenerator grid, and thus conveniently and accurately regulate the gas volume entering each vertical flue. It can make the regulation of the horizontal row temperature of the combustion chamber, especially the temperature of the furnace head flue, more rapid and efficient, so as to ensure the uniformity of the longitudinal heating of the coke and the maturity of the furnace head coke cake.

[0032] Since the coke oven body expands along the machine side - coke side direction during the coke oven baking process, and its expansion rate is greater than that of the foundation roof slab 21, a sliding joint needs to be arranged between the bottom of the small flue 22 and the foundation roof slab 21. In order to prevent the lean gas down-spray pipe 14 from being squeezed and deformed or even broken during the expansion of the coke oven, the lean gas down-spray pipe 14 is disconnected at the sliding joint, that is, it is divided into an upper pipe 143 of the down-spray pipe and a lower pipe 141 of the down-spray pipe, and a flared structure 142 is arranged at the bottom of the upper pipe 143 of the down-spray pipe. During cold-state masonry, the centers of the upper pipe 143 of the down-spray pipe at the center position of the coke oven and the centers of the corresponding lower pipes 141 of the down-spray pipe coincide, while along the direction from the center of the coke oven to the machine side or along the direction from the center of the coke oven to the coke side, the centers of the upper pipe 143 of the down-spray pipe and the centers of the corresponding lower pipes 141 of the down-spray pipe are staggered, and the farther away from the center, the greater the staggering distance (as Figure 1 shown), but it is necessary to ensure that the outlet of the lower pipe 141 of the down-spray pipe is always located within the flared structure 142 at the bottom of the upper pipe 143 of the down-spray pipe. During hot-state baking, the coke oven body expands towards both the machine and coke sides, and after the baking is completed, the centers of all the upper pipes 143 of the down-spray pipes coincide with the centers of the corresponding lower pipes 141 of the down-spray pipes.

[0033] Since the amount of lean gas required for coke oven heating is relatively large, the flow rate of the lean gas coming out of the lean gas down-spray pipe 14 is relatively large. Therefore, it will enter the regenerator 2 in a concentrated state of high-speed spraying, resulting in the grid bricks far away from the gas inlet not being utilized, reducing the thermal efficiency of the regenerator and increasing the gas consumption. Therefore, the present utility model arranges an air flow distribution device 144 at the top of the lean gas down-spray pipe 14. The air flow distribution device 144 is arranged along the machine side - coke side direction, and can make the lean gas evenly distributed in the grid bricks 24 at the bottom of the regenerator 2, thereby greatly improving the utilization rate of the grid bricks in the regenerator.

[0034] Since the coke oven waste gas contains acidic gases such as SO2 and NOx, the upper pipe 143 of the downcomer that is in direct contact with the waste gas needs to be made of heat-resistant stainless steel pipe or refractory pipe bricks, etc., to prevent the acidic waste gas from corroding the upper pipe 143 of the downcomer and improve its service life. The lower pipe 141 of the downcomer is embedded in the basic roof plate 21, does not contact the waste gas, only contacts the lean gas, and there is no acidic corrosion environment, so ordinary metal pipes made of carbon steel and other materials can be used to reduce the investment.

[0035] To make the purpose, technical solution and technical effect of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be described clearly and completely now. However, the embodiments described below are only part of the embodiments of the present utility model, rather than all the embodiments. Combining the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the scope of protection of the present utility model.

[0036]

Embodiment 1

[0037] As Figure 3 shown, in this embodiment, the lean gas downcomer 14 is composed of the lower pipe 141 of the downcomer and the upper pipe 143 of the downcomer. The lower pipe 141 of the downcomer is made of a steel pipe of Q235B material with a wall thickness of 5 mm. A gas flow regulating device 15 is provided in the middle of the lower pipe 141 of the downcomer. In this embodiment, the gas flow regulating device 15 is an orifice plate flow regulating device, and the flow rate of the lean gas in the lean gas downcomer 14 can be adjusted by replacing the orifice plate. The lower end of the lower pipe 141 of the downcomer is connected to the lean gas cross pipe 13, and the top end of the lower pipe 11 of the downcomer is embedded in the basic roof plate 21 of the coke oven, and the top surface is 10 mm higher than the upper surface of the basic roof plate 21 to ensure the airtightness at the sliding joint between the bottom brick 25 of the small flue and the basic roof plate 21.

[0038] In this embodiment, the upper pipe 143 of the downcomer is made of austenitic stainless steel pipe with a wall thickness of 5 mm, and a flared structure is provided at the bottom, and the flared structure is built inside the bottom brick 25 of the small flue.

[0039] In this embodiment, the centers of the lower pipes 141 of the downcomers at the center position of the coke oven coincide with the centers of the corresponding upper pipes 143 of the downcomers. However, along the direction from the center of the coke oven to the machine side and from the center of the coke oven to the coke side, the centers of the lower pipes 141 of the downcomers and the centers of the corresponding upper pipes 143 of the downcomers are offset, and the offset distance is larger the farther away from the center of the coke oven. But the outlets of all the lower pipes 141 of the downcomers are located within the flared structures 14 of the corresponding upper pipes 143 of the downcomers. As Figure 1As shown in the figure, in the illustrated direction, the centerlines of the lower pipes 141 of the lower gas injection pipes on the coke side are all on the left side of the centerlines of the upper pipes 143 of the corresponding lower gas injection pipes. The centerlines of the lower pipes 141 of the lower gas injection pipes on the machine side are all on the right side of the centerlines of the upper pipes 143 of the corresponding lower gas injection pipes. After the hot state expansion of the coke oven body during oven drying, the centerlines of the corresponding upper pipes 143 and lower pipes 141 of the lower gas injection pipes coincide.

[0040] In this embodiment, the gas flow distribution device 144 at the top of the upper pipe 143 of the lower gas injection pipe is a gas flow distribution cylinder made of heat-resistant stainless steel pipe. It is located between the checker bricks 24 and the grid bricks 23 and is arranged in the machine side - coke side direction. Air holes are evenly opened on both sides of the gas flow distribution cylinder, which can enable the lean gas to enter the regenerator evenly at the bottom of the checker bricks 24 for preheating in the checker bricks, thereby improving the heat exchange efficiency of the regenerator.

[0041]

Embodiment 2

[0042] As Figure 4 shown, in this embodiment, the lean gas lower gas injection pipe 14 is composed of a lower pipe 141 and an upper pipe 143 of the lower gas injection pipe. The lower pipe 141 of the lower gas injection pipe is made of a steel pipe of Q235B material with a wall thickness of 6 mm. A gas flow regulating device 15 is provided in the middle of the lower pipe 143 of the lower gas injection pipe. In this embodiment, the gas flow regulating device 15 is an orifice plate flow regulating device, and the flow rate of the lean gas in the lean gas lower gas injection pipe 14 can be adjusted by replacing the orifice plate. The lower end of the lower pipe 141 of the lower gas injection pipe is connected to the lean gas cross pipe 13. The top end of the lower pipe 11 of the lower gas injection pipe is embedded in the foundation roof slab 21 of the coke oven, and the top surface is 15 mm higher than the upper surface of the foundation roof slab 21 to ensure the airtightness at the sliding joint between the bottom brick 25 of the small flue and the foundation roof slab 21.

[0043] In this embodiment, the upper pipe 143 of the lower gas injection pipe is made of fireclay pipe bricks and has a flared structure 142 at the bottom. The flared structure 142 is built inside the bottom brick 25 of the small flue. The pipe bricks forming the upper pipe 143 of the lower gas injection pipe and the flared structure 142 are built using an interlocking structure.

[0044] In this embodiment, the gas flow distribution device 144 at the top of the upper pipe 142 of the lower gas injection pipe is a gas flow distribution cone with a flared structure. The gas flow distribution cone is made of pipe bricks and is arranged in the grid bricks. An interlocking structure is also used between the grid bricks and the pipe bricks to ensure airtightness. The gas flow distribution cone is arranged in the machine side - coke side direction, which can enable the lean gas to enter the regenerator 2 evenly at the bottom of the checker bricks 24 for preheating in the checker bricks, thereby improving the heat exchange efficiency of the regenerator.

[0045] The above are only the preferred specific embodiments of the present utility model, but the protection scope of the present utility model is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present utility model, according to the technical solution and inventive concept of the present utility model, making equivalent substitutions or changes, shall be covered by the protection scope of the present utility model.

Claims

1. A down-spray coke oven structure for lean gas, comprising a carbonization chamber, a combustion chamber and a regenerator; characterized in that, It also includes a lean gas down-spraying system; the regenerator is a grid-type regenerator; the lean gas down-spraying system is composed of a lean gas main pipe, a lean gas branch pipe, a lean gas cross pipe and a lean gas down-spraying pipe connected in sequence, and the lean gas down-spraying pipes are arranged in one-to-one correspondence with each regenerator; the lean gas down-spraying pipe is composed of an upper down-spraying pipe and a lower down-spraying pipe; the lower end of the lower down-spraying pipe is connected to the lean gas cross pipe, the upper end of the lower down-spraying pipe penetrates upward from the foundation roof slab of the coke oven, and a gas flow regulating device is arranged on the lower down-spraying pipe; the lower end of the upper down-spraying pipe is provided with a flared structure and is movably connected to the lower down-spraying pipe, the upper end of the upper down-spraying pipe penetrates upward from the corresponding small flue and grid brick, and an air flow distribution device is arranged at the top end of the upper down-spraying pipe.

2. The structure of a lean gas downward injection coke oven according to claim 1, characterized in that, The flared structure is arranged in the bottom brick of the small flue.

3. The structure of a lean gas down-spray coke oven according to claim 1, characterized in that, The air flow distribution device is arranged at the top of the grid brick and the bottom of the checker brick.

4. A structure of a lean gas down-spray coke oven according to claim 1 or 3, characterized in that, The air flow distribution device is an air flow distribution cylinder, which is arranged along the machine side-coke side direction, and air holes are respectively arranged on both sides of the air flow distribution cylinder.

5. A structure of a lean gas down-spray coke oven according to claim 1 or 3, characterized in that, The air flow distribution device is an air flow distribution cone, which is arranged along the machine side-coke side direction, and the width of the upper opening of the air flow distribution cone is greater than the width of the lower opening.

6. The structure of a lean gas down-spray coke oven according to claim 1, characterized in that, The lower down-spraying pipe is a metal pipe.

7. The structure of a lean gas down-spray coke oven according to claim 1, characterized in that, The upper down-spraying pipe is a heat-resistant stainless steel pipe with a wall thickness of 3-8 mm.

8. A structure of a lean gas down-spray coke oven according to claim 1, characterized in that, The upper down-spraying pipe is built by pipe bricks, and the pipe bricks are built by an inlay structure.

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