A composite self-decoking cracking furnace
By designing a composite self-decoking cracking furnace, the separation of coke particles and carbon black is achieved, and equipment demand is reduced through cooling measures, the problems of coke particles impurities and high-temperature products in the prior art are solved, and production costs are reduced.
Patent Information
- Application Number
- CN202411968456.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-04-04
AI Technical Summary
After the acetylene cracking reaction, the existing cracking furnace is mixed with a large amount of coke particles and metal foreign matter in the product, which makes it difficult to separate the subsequent process. At the same time, the high temperature of the reaction product requires increasing cooling equipment and increasing production costs.
A composite self-decoking cracking furnace is designed, including a cracking zone, a cooling zone, a decoking zone and a slag discharge zone. By setting up a purge device and a cooling device, the coke particles and carbon black are separated, and the cooling is reduced through an annular nitrogen port and a cooling water jacket to reduce subsequent equipment needs.
Effectively removes coke impurities in carbon black, reduces the impurity content of carbon black, and reduces the subsequent equipment demand through cooling measures and reduces production costs.
Smart Images
Figure CN119752464A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of cracking furnaces, and in particular relates to a composite self-decoking cracking furnace. Background Art
[0002] In the carbon black production process, the cracking reaction of acetylene is completed through a cracking furnace. The cracking reaction of acetylene will cause coke particles, metal foreign matter, etc. to be mixed into the carbon black, making online separation more difficult. The main reason for this is that the coke blocks produced in the furnace are not discharged in time, resulting in repeated collisions between the subsequent two-stage cooling spirals, grinders, and fans and the coke blocks. The collision of coke blocks will produce tiny coke particles and metal foreign matter, which makes it impossible to separate them in subsequent processes. Although there are currently offline decoking processes in China, the overall production process cost is relatively high.
[0003] Meanwhile, the temperature of carbon black after the cracking furnace reaction in the prior art is relatively high, and it is necessary to add post-process equipment such as a two-stage cooling spiral to achieve this, which increases production costs. Summary of the invention
[0004] The purpose of the present invention is to provide a composite self-decoking pyrolysis furnace to solve the problems that the carbon black produced by the pyrolysis furnace in the prior art is mixed with a large amount of metal foreign matter such as coke particles, and the reaction product temperature of the pyrolysis furnace is too high, and subsequent cooling equipment needs to be added, resulting in high production costs. In order to achieve the above purpose, the present invention provides the following technical solutions:
[0005] A composite self-decoking cracking furnace is used for cracking acetylene, wherein the cracking produces carbon black, coke particles and hydrogen-rich gas, and comprises a cracking zone, a cooling zone, a decoking zone and a slag discharge zone which are sequentially connected from top to bottom; acetylene is input into the inlet of the cracking zone for cracking reaction; the cooling zone is used for cooling the product after the acetylene cracking reaction; the decoking zone is provided with a purge device for separating coke particles from carbon black and hydrogen-rich gas; the slag discharge zone is used for discharging coke particles; the cracking zone, the cooling zone and the decoking zone are all provided with cooling devices for cooling the cracking zone, the cooling zone and the decoking zone.
[0006] Furthermore, the cooling device includes a first cooling pipe; the first cooling pipe is wound around the outer wall of the cracking zone, and includes a first water inlet arranged on the lower side wall of the cracking zone and a first water outlet arranged on the upper side wall of the cracking zone.
[0007] Furthermore, the cooling device also includes a second cooling pipe; the second cooling pipe includes a second water inlet arranged at the end of the decoking zone and a second water outlet at the upper end of the cooling zone; the second cooling pipe covers the outer walls of the decoking zone and the cooling zone.
[0008] Furthermore, the cooling device also includes a plurality of first nitrogen inlets; the plurality of first nitrogen inlets are arranged around the outer wall of the cooling zone and close to the upper end of the cooling zone.
[0009] Furthermore, the purging device includes a guide pipe and a guide plate; the guide pipe is arranged near the lower end of the decoking zone, and is used to introduce reflux hydrogen gas; the guide plate is fixed at the outlet of the guide pipe; and a discharge port is provided on one side of the decoking zone near the upper end.
[0010] Furthermore, the slag discharge area includes a small silo and a slag outlet; an upper valve and a lower valve are respectively provided above and below the small silo; the small silo is connected to the lower end of the slag removal area through the upper valve, and the small silo is connected to the upper end of the slag outlet through the lower valve.
[0011] Furthermore, the side wall of the cooling zone is provided with an explosion vent for the cooling zone; and the side wall of the decoking zone is provided with an explosion vent for the decoking zone.
[0012] Furthermore, a second nitrogen inlet is provided on the side wall of the decoking zone near the lower end; the outlet of the second nitrogen inlet faces the small silo.
[0013] Furthermore, a third nitrogen port is provided on the side wall of the small silo near the lower end; the outlet of the third nitrogen port faces upward.
[0014] Furthermore, the cooling zone is provided with a temperature measuring point in the cooling zone; the decoking zone is provided with a temperature measuring point in the decoking zone; and the discharge port is provided with a temperature measuring point in the discharge port.
[0015] The beneficial effects of the present invention are as follows: the present invention separates and removes coke particles by setting a decoking zone, thereby ensuring that the impurities in the carbon black product are lower, and at the same time, the reaction product is cooled by a first nitrogen port arranged in an annular manner, and the reaction product is cooled by a water jacket formed by the second cooling pipe on the outer wall of the cooling zone and the decoking zone, thereby reducing the cooling equipment in subsequent process equipment and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is a structural schematic diagram of the present invention;
[0017] In the figure: 1. First water outlet; 2. First water inlet; 3. Second water outlet; 4. First nitrogen inlet; 5. Explosion vent in cooling zone; 6. Temperature measuring point in cooling zone; 7. Temperature measuring point in decoking zone; 8. Inspection manhole; 9. Second cooling pipe; 10. Guide plate; 11. Second water inlet; 12. Guide pipe; 13. Upper valve; 14. Small silo; 15. Third nitrogen inlet; 16. Lower valve; 17. Temperature measuring point in discharge port; 18. Discharge port; 19. Cracking zone; 20. Cooling zone; 21. Decoking zone; 22. Slag discharge zone. DETAILED DESCRIPTION
[0018] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.
[0019] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invention product is usually placed when used, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In addition, the terms "horizontal", "vertical", etc. do not mean that the components are absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0020] Example:
[0021] like Figure 1As shown, a composite self-decoking cracking furnace is used to produce carbon black by cracking acetylene. From top to bottom, it includes a cracking zone 19, a cooling zone 20, a decoking zone 21 and a slag discharge zone 22, all of which are high temperature and corrosion resistant steel structures. The lower end of the cracking zone 19 is connected to the cooling zone 20. The cracking zone 19 is used for the high temperature cracking reaction of acetylene. The carbon black, coke particles and hydrogen-rich gas generated by the reaction enter the cooling zone 20 from the bottom of the cracking zone 19. The cooling device includes a first cooling pipe, which is wound around the outer wall of the cracking zone 19. Cooling water is connected from the first water inlet 2 of the cracking zone 19 and flows out from the first water outlet 1 at the upper end of the cracking zone 19. Cooling water is continuously introduced to cool the cracking zone 19.
[0022] The cooling zone 20 is used to cool the product after the reaction to ensure that its temperature is closer to the temperature required for the final output. A number of first nitrogen ports 4 are evenly arranged in a ring shape on the side wall of the cooling zone 20, and an external nitrogen output device is connected to cool the reaction product by injecting nitrogen, which has a good effect on terminating the reaction and preventing it from continuing to react in the cooling zone 20 due to excessive temperature. The cooling zone 20 is connected to the decoking zone 21 below, and the cooling device also includes a second cooling pipe 9 provided on the cooling zone 20 and the decoking zone 21 to further cool down. The second water inlet 11 of the second cooling pipe 9 is set at the lower end of the decoking zone 21, and the second water outlet 3 is set at the upper end of the cooling zone 20. The length of the second cooling water pipe is sufficient to cover the outer walls of the decoking zone 21 and the cooling zone 20, and can be set to a jacket structure to further cool the cooling zone 20 and the decoking zone 21, as shown in the attached Figure 1 As shown, the lower half of the cooling zone 20 is embedded in the decoking zone 21, and cooling water is introduced at the upper end of the degumming zone and the lower end of the cooling zone 20 by setting a connecting pipe to ensure that the cooling water in the second cooling pipe 9 flows from the lower end to the upper end in both the decoking zone 21 and the cooling zone 20, thereby ensuring the cooling effect of the cooling water.
[0023] The lower side wall of the decoking zone 21 is provided with a guide pipe 12, which is connected to the reflux hydrogen gas. The reflux hydrogen gas flows from the guide pipe 12 to the lower end of the decoking zone 21 with a certain power. A guide plate 10 is provided on the inner wall of the decoking zone 21, which is aligned with the guide pipe 12. The reflux hydrogen gas entering from the guide pipe 12 forms an ascending cyclone gas inside the decoking zone 21 through the action of the guide plate 10. The lighter hydrogen-rich gas and carbon black are discharged from the discharge port 18 on the upper side wall of the decoking zone 21 by the principle of centrifugal separation of materials and sinking of heavy materials; while the heavier coke particles stay at the lower end of the decoking zone 21 due to gravity. A certain drop is left from the outlet of the cooling zone 20 to the bottom of the decoking zone 21 to ensure that the coke particles, carbon black and hydrogen-rich gas are fully affected by the ascending cyclone gas, and the separation of coke particles, carbon black and hydrogen-rich gas is completed. A maintenance manhole 8 is also provided on the side wall of the decoking area 21 for subsequent maintenance of the equipment, which is convenient for operators to perform maintenance.
[0024] The slag discharge area 22 includes a small silo 14 and a slag outlet. The upper and lower ends of the small silo 14 are respectively provided with an upper valve 13 and a lower valve 16. The upper end of the small silo 14 is connected to the lower end of the decoking area 21 through the upper valve 13, and the lower end of the small silo 14 is connected to the slag outlet through the lower valve 16. A second nitrogen port is provided on one side of the lower end of the decoking area 21. The outlet of the second nitrogen port faces the small silo 14. The coke particles are blown into the small silo 14 by the nitrogen, and a certain temperature reduction effect is also achieved.
[0025] A third nitrogen port 15 is provided on one side of the lower end of the small silo 14. The nitrogen outlet of the third nitrogen port 15 faces upward, and is used to introduce nitrogen to blow the small silo 14 upward, so as to displace the residual hydrogen-rich gas in the small silo 14, so as to avoid that when the coke particles are discharged from the slag outlet, too much hydrogen-rich gas is discharged together, which poses a great safety hazard. When slag discharge is required, the upper valve 13 of the small silo 14 needs to be opened, and the coke particles are purged through the second nitrogen port and all enter the small silo 14; then stop purging the second nitrogen port, open the third nitrogen port 15 for purging, and purge and replace the hydrogen-rich gas in the small silo 14. When the replacement is complete, close the upper valve 13 of the small silo 14, open the lower valve 16 of the small silo 14, and discharge the coke particles. In this way, the interior of the furnace body can be safely and effectively blocked from directly contacting the external air, which may cause a deflagration safety accident.
[0026] To further ensure the safe operation of the entire cracking furnace, a cooling zone explosion vent 5 is provided in the cooling zone 20 and a decoking zone explosion vent is provided in the decoking zone 21, which are used to release excess pressure in the reaction process, avoid equipment rupture, reduce the probability of accidents, and provide a safe environment.
[0027] The cracking furnace of the present invention is provided with a temperature measuring point 6 in the cooling zone 20 in the middle position, a temperature measuring point 7 in the decoking zone 21 in the middle position, and a temperature measuring point 17 at the discharge port 18, so as to strengthen the monitoring of the temperature of the material and the tail gas, and ensure the safe, reliable and convenient operation. Due to the high temperature in the furnace, the traditional cracking furnace often does not detect the temperature in the furnace, but only detects the outlet water temperature and the outlet material temperature. In this way, it is difficult to control the actual temperature in the furnace, and more experience accumulation is required to use the furnace. There is another problem that the traditional cracking furnace does not add temperature measurement, that is, the temperature in the furnace is high (1400-1800℃), and conventional thermocouples cannot withstand this temperature, and even if they are used, the damage rate is high. In addition, the price of this type of high temperature resistant thermocouple is relatively high, and its use cost is relatively large. The present invention is provided with a first nitrogen port 4 arranged in a ring shape, and after the material and hydrogen-rich gas are forced to cool down, the water jacket furnace wall formed by the cooling water pipe is cooled down, and then we detect the temperature again. The temperature measuring point 6 in the cooling zone 20 is set in the middle of the cooling zone. Usually, the temperature range is (600-1000°C), which increases the types and ranges of thermocouples we can choose. At the same time, it also avoids the high cost of high-temperature thermocouples.
[0028] The invention can remove the two-stage cooling spiral and grinding machine in the traditional process from the process point of view, effectively saving energy input cost and production cost. From the use point of view, it can effectively remove a large amount of coke particles in the front section of the fan, reduce the temperature of the fan incoming material, reduce the wear of the fan impeller, increase the service life of the fan, and improve the enterprise efficiency.
[0029] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.
Claims
1. A composite self-decoking cracking furnace for cracking acetylene, which produces carbon black, coke particles and hydrogen-rich gas, characterized in that: The invention comprises a cracking zone (19), a cooling zone (20), a decoking zone (21) and a slag discharge zone (22) which are connected in sequence from top to bottom; acetylene is inputted into the inlet of the cracking zone (19) for cracking reaction; the cooling zone (20) is used for cooling the product after the acetylene cracking reaction; the decoking zone (21) is provided with a purge device for separating coke particles from carbon black and hydrogen-rich gas; the slag discharge zone (22) is used for discharging coke particles; the cracking zone (19), the cooling zone (20) and the decoking zone (21) are all provided with cooling devices for cooling the cracking zone (19), the cooling zone (20) and the decoking zone (21).
2. A composite self-decoking pyrolysis furnace according to claim 1, characterized in that: The cooling device comprises a first cooling pipe; the first cooling pipe is wound around the outer wall of the cracking zone (19), and comprises a first water inlet (2) arranged on the lower side wall of the cracking zone (19) and a first water outlet (1) arranged on the upper side wall of the cracking zone (19).
3. A composite self-decoking pyrolysis furnace according to claim 2, characterized in that: The cooling device further comprises a second cooling pipe (9); the second cooling pipe (9) comprises a second water inlet (11) arranged at the end of the decoking zone (21) and a second water outlet (3) at the upper end of the cooling zone (20); the second cooling pipe (9) covers the outer walls of the decoking zone (21) and the cooling zone (20).
4. A composite self-decoking pyrolysis furnace according to claim 3, characterized in that: The cooling device further comprises a plurality of first nitrogen ports (4); the plurality of first nitrogen ports (4) are arranged around the outer wall of the cooling zone (20) and close to the upper end of the cooling zone (20).
5. A composite self-decoking pyrolysis furnace according to claim 4, characterized in that: The purging device comprises a guide pipe (12) and a guide plate (10); the guide pipe (12) is arranged near the lower end of the decoking zone (21) and is used to introduce reflux hydrogen gas; the guide plate (10) is fixed at the outlet of the guide pipe (12); and a discharge port (18) is provided on one side near the upper end of the decoking zone (21).
6. A composite self-decoking pyrolysis furnace according to claim 5, characterized in that: The slag discharge area (22) comprises a small material bin (14) and a slag discharge port; an upper valve (13) and a lower valve (16) are respectively provided above and below the small material bin (14); the small material bin (14) is connected to the lower end of the slag discharge area via the upper valve (13), and the small material bin (14) is connected to the upper end of the slag discharge port via the lower valve (16).
7. A composite self-decoking pyrolysis furnace according to claim 6, characterized in that: The side wall of the cooling zone (20) is provided with a cooling zone explosion vent (5); the side wall of the decoking zone (21) is provided with a decoking zone explosion vent.
8. A composite self-decoking pyrolysis furnace according to claim 7, characterized in that: A second nitrogen inlet is provided on the side wall of the decoking zone (21) near the lower end; the outlet of the second nitrogen inlet faces the small silo (14).
9. A composite self-decoking pyrolysis furnace according to claim 8, characterized in that: A third nitrogen port (15) is provided on the side wall of the small material bin (14) near the lower end; the outlet of the third nitrogen port (15) faces upward.
10. A composite self-decoking pyrolysis furnace according to claim 9, characterized in that: The cooling zone (20) is provided with a cooling zone temperature measuring point (6); the decoking zone (21) is provided with a decoking zone temperature measuring point (7); and the discharge port (18) is provided with a discharge port temperature measuring point (17).