Petroleum coke drying calcination system

Abstract

The present application provides a kind of petroleum coke drying calcination system, belong to tar processing technical field, including: feed bin, waste heat rotary drying furnace, calcining furnace, cold slag machine and receiving bin, also include with calcining furnace is connected exhaust gas incinerator.Petroleum coke green coke raw material is sent into waste heat rotary drying furnace and dries;Waste heat rotary drying furnace is provided with drying furnace water vapor outlet, drying furnace smoke outlet and drying furnace waste heat tail gas import;The high-temperature tail gas of material calcination volatilization in calcining furnace enters exhaust gas incinerator through calcining furnace tail gas volatilization, and the high-temperature tail gas produced by mixing combustion with the fuel gas entering exhaust gas incinerator, into calcining furnace, and with the material in calcining furnace reverse flow, calcination material in calcining furnace, realize the first use of tail gas.High-temperature tail gas forms low-temperature tail gas after calcination endothermic, enters waste heat rotary drying furnace and dries material, realize the second use of tail gas, solve the problem of low degree of integration, high production cost and low processing efficiency.

Description

Technical Field

[0001] This invention belongs to the field of tar treatment technology, specifically relating to a petroleum coke drying and calcination system. Background Technology

[0002] In the production of artificial graphite, the pretreatment of raw material petroleum coke is crucial. Petroleum coke is a byproduct of petroleum refining, with raw petroleum coke being a primary product. It is produced directly in a delayed coking unit without subsequent high-temperature (1200-1350℃) calcination. Artificial graphite made solely from raw petroleum coke has insufficient energy density; while artificial graphite made solely from calcined coke also has deficiencies in rate performance. Therefore, to produce artificial graphite that balances both aspects, the raw petroleum coke raw material needs to be semi-calcined (calcination temperature 600-900℃) to meet the requirements.

[0003] The existing technologies currently in use have the following shortcomings:

[0004] (1) The direct use of natural gas resources for calcination without preheating and recovery treatment results in a high cost per ton, which is not conducive to the company's cost control.

[0005] (2) Petroleum coke raw coke is semi-calcined in separate processes, such as coarse crushing, drying and calcination. Various wastes occur in the flow between processes, and the production line is not integrated, resulting in low processing efficiency and high production costs. Summary of the Invention

[0006] This invention provides a petroleum coke drying and calcination system, which aims to solve the problems of low integration, high production cost, and low processing efficiency in the calcination of raw petroleum coke.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is: to provide a petroleum coke drying and calcining system, comprising: a feeding hopper, a waste heat rotary dryer, a calcining furnace, a slag cooler and a receiving hopper connected in sequence, and further comprising a tail gas combustion chamber connected to the calcining furnace;

[0008] Petroleum coke raw material is fed into the feeding hopper, pre-treated, and then sent to the waste heat rotary dryer for drying; the material dried in the waste heat rotary dryer enters the calcining furnace for calcination; the calcined material enters the slag cooler for cooling and is temporarily stored in the receiving hopper.

[0009] The waste heat rotary dryer is equipped with a drying furnace water vapor outlet, a drying furnace flue gas outlet and a drying furnace waste heat exhaust gas inlet; the water vapor discharged after the material in the waste heat rotary dryer is dried is discharged from the drying furnace water vapor outlet, and the exhaust gas generated is discharged from the drying furnace flue gas outlet.

[0010] The high-temperature exhaust gas generated by the calcination of materials in the calcination furnace enters the exhaust gas combustion chamber through the exhaust gas evaporation port of the calcination furnace. It mixes and burns with the fuel gas entering the exhaust gas combustion chamber to generate high-temperature exhaust gas, which then enters the calcination furnace and flows in the opposite direction to the materials in the calcination furnace, calcining the materials in the calcination furnace and realizing the one-time utilization of the exhaust gas.

[0011] The high-temperature exhaust gas is calcined and absorbs heat to form low-temperature exhaust gas, which enters the waste heat rotary dryer through the waste heat exhaust gas inlet of the dryer to dry the material, thus realizing the secondary utilization of the exhaust gas.

[0012] In one possible implementation, the pretreatment before the waste heat rotary dryer includes a coarse pretreatment, which includes: the material in the feeding hopper is fed by a vibrating feeder installed at the outlet of the feeding hopper onto the double roll crusher below, and after being crushed, it enters the double roll crushing hopper and falls into the drying furnace feed auger below, and is sent into the waste heat rotary dryer for drying.

[0013] In one feasible approach, the pretreatment before the waste heat rotary dryer includes fine pretreatment, which includes: the material in the feeding hopper is fed to the double-roll crusher below by a vibrating feeder installed at the discharge port of the feeding hopper; the crushed material is fed into the linear screen feed hopper for temporary storage by a crushing and feeding elevator; after being screened by the linear screen, the large material on the screen enters the waste heat rotary dryer for drying via a conveyor belt; the undersized material falls onto the vertical discharge screen below via the vertical discharge screen feed hopper; the small undersized material falls into the small undersized material hopper for temporary storage; and the oversized material from the vertical discharge screen falls into the oversized material hopper for temporary storage.

[0014] In one possible implementation, the waste heat exhaust gas inlet of the drying furnace is located at one end of the drying furnace discharge port near the waste heat rotary drying furnace, and the water vapor outlet and the flue gas outlet of the drying furnace are located at the end of the drying furnace inlet near the waste heat rotary drying furnace.

[0015] In one possible implementation, a feeding mechanism is provided between the waste heat rotary dryer and the calcining furnace. The feeding mechanism includes a pit elevator connected to the dryer discharge port of the waste heat rotary dryer, a ground elevator connected to the pit elevator, a calcining feed hopper for temporarily storing the material lifted by the ground elevator, and a calcining feed conveyor for feeding the material into the calcining furnace.

[0016] In one possible embodiment, the calcining furnace includes a calcining shell, a calcining heating pipe coaxially fitted inside the calcining shell, and a ring of calcining material pipes disposed between the calcining heating pipes and the calcining shell; the calcining furnace exhaust gas evaporation port is disposed on the calcining material pipes; the high-temperature exhaust gas enters from the end of the calcining heating pipe near the calcining discharge port, and after calcination and cooling, exits from the end of the calcining heating pipe near the calcining inlet, and enters the waste heat rotary drying furnace.

[0017] In one possible implementation, an emergency vent is provided on the high-temperature gas outlet pipe of the incineration chamber, which connects the exhaust gas incineration chamber to the calcination heating pipe.

[0018] In one possible configuration, the calcining furnace is arranged at an angle of 5-10° to the horizontal plane, and the calcining discharge port is lower than the calcining feed port.

[0019] In one possible implementation, a calcination rotary drive mechanism is provided outside the calcination furnace, and calcination support wheels are respectively provided at both ends of the calcination furnace; the calcination rotary drive mechanism includes a calcination drive motor 93, a drive gear mounted on the main shaft of the calcination drive motor 93, and a gear ring mounted around the calcination furnace, the gear ring meshing with the drive gear.

[0020] In one possible implementation, the cold slag machine is provided with a cold slag inlet, a dredging port for clearing blockages is provided below the cold slag inlet, and an emergency discharge port is provided below the dredging port.

[0021] The petroleum coke drying and calcining system provided by this invention has the following advantages compared with the prior art:

[0022] (1) Reduced production costs: Existing technologies directly use natural gas for calcination without preheating and recovery, resulting in high costs per ton. In this solution, the high-temperature exhaust gas volatilized from the calcination furnace is mixed with fuel gas in the exhaust gas incineration chamber for combustion. The high-temperature exhaust gas first enters the calcination furnace to calcine the material, achieving primary utilization of the exhaust gas. After absorbing heat through calcination, the high-temperature exhaust gas becomes low-temperature exhaust gas, which then enters the waste heat rotary drying furnace to dry the material, achieving secondary utilization of the exhaust gas. This waste heat recovery method reduces the consumption of energy such as natural gas, thereby reducing the calcination cost per ton of petroleum coke and facilitating the company's cost control.

[0023] (2) Improve processing efficiency: Existing technologies perform semi-calcination of raw petroleum coke in separate processes, resulting in waste during inter-process transfers and low processing efficiency due to the lack of production line integration. This technical solution adopts an integrated design, connecting the feeding silo, waste heat rotary dryer, calcining furnace, slag cooler, and receiving silo in sequence. The raw petroleum coke raw material flows sequentially between the various devices, realizing continuous operation of drying, calcination, and other processes, reducing waste during inter-process transfers, improving processing efficiency, and lowering production costs.

[0024] (3) Ensure product quality: Through the rational design of the waste heat rotary drying furnace and calcining furnace, and the double utilization of tail gas, the raw petroleum coke can be dried and calcined under more stable temperature and heat conditions, which helps to ensure the quality of semi-calcined petroleum coke, thus providing high-quality raw materials for the production of artificial graphite with both energy density and rate performance.

[0025] (4) Significant environmental benefits: The system makes full use of exhaust gas, reduces heat loss and environmental pollution caused by direct emission of high-temperature exhaust gas, meets the requirements of energy conservation and environmental protection, and helps enterprises achieve green production.

[0026] This invention effectively solves the problems of low integration, high production cost, and low processing efficiency in existing technologies by integrating and continuously operating processes such as drying and calcination, as well as repeatedly utilizing exhaust gas. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the petroleum coke drying and calcining system provided in an embodiment of the present invention;

[0028] Figure 2 A schematic diagram of the feeding silo and waste heat rotary dryer of the petroleum coke drying and calcining system provided in an embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of the feeding mechanism of the petroleum coke drying and calcining system provided in an embodiment of the present invention;

[0030] Figure 4 A schematic diagram (appearance) of the calcining furnace in the petroleum coke drying and calcining system provided in an embodiment of the present invention.

[0031] Figure 5 A schematic diagram (internal) of the calcining furnace in the petroleum coke drying and calcining system provided in an embodiment of the present invention.

[0032] Figure 6 This is a schematic diagram of the tail gas incinerator and slag cooler of the petroleum coke drying and calcining system provided in an embodiment of the present invention;

[0033] Figure 7This is a schematic diagram of the structure of the slag cooler in the petroleum coke drying and calcining system provided in an embodiment of the present invention;

[0034] Figure 8 This is a schematic diagram of the fine pretreatment section of the petroleum coke drying and calcining system provided in an embodiment of the present invention;

[0035] Figure 9 A schematic diagram of the structure of the inner cylinder of the drying oven provided in an embodiment of the present invention (showing the internal spiral blades).

[0036] Explanation of reference numerals in the attached figures:

[0037] 1. Feeding bin; 2. Vibrating feeder; 3. Double roll crusher; 4. Double roll crusher hopper; 5. Waste heat rotary dryer; 51. Dryer feed auger; 52. Dryer drive motor; 53. Dryer support wheel; 54. Dryer inner cylinder; 541. Spiral blade; 55. Dryer heating chamber; 56. Dryer waste heat exhaust gas inlet; 57. Dryer discharge port; 58. Dryer steam outlet; 59. Dryer flue gas outlet; 591. Dryer outer cylinder; 6. Feeding mechanism; 61. Pit elevator; 62. Above-ground elevator; 7. Calcination feed bin; 8. Calcination feed conveyor; 9. Calcination furnace; 91. Calcination feed inlet; 92. Calcination support wheel; 93. Calcination drive motor; 94. Calcination discharge port; 95. 96. Calcining furnace exhaust gas evaporation port; 97. Calcining heating pipeline; 98. Calcining material pipeline; 99. Calcining shell; 10. Emergency vent; 11. Calcining unloading valve; 12. Slag cooler; 13. Slag inlet; 14. Unblocking port; 15. Emergency discharge port; 16. Bucket elevator; 17. Receiving bin; 18. Discharge valve; 19. Exhaust gas combustion chamber; 20. Combustion chamber natural gas inlet; 21. Combustion chamber air inlet pipeline; 22. Combustion chamber high-temperature exhaust pipeline; 23. Exhaust fan; 24. Crushing and feeding elevator; 25. Linear screen feed bin; 26. Linear screen; 27. Conveyor belt; 28. Direct discharge screen feed bin; 29. ​​Direct discharge screen; 20. Over-screen material bin; 21. Under-screen small material bin. Detailed Implementation

[0038] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0039] Please refer to sections 1 to 2. Figure 8The petroleum coke drying and calcining system provided by the present invention will now be described. The petroleum coke drying and calcining system, in the direction of the process flow, includes: a feeding hopper 1, a waste heat rotary dryer 5, a calcining furnace 9, a slag cooler 11, and a receiving hopper 13 connected in sequence, and also includes a tail gas combustion chamber 15 connected to the calcining furnace 9.

[0040] The basic process flow of petroleum coke is as follows: raw petroleum coke is fed into the feeding silo 1, and after pretreatment, it is sent into the waste heat rotary dryer 5 for drying; the material dried in the waste heat rotary dryer 5 enters the calcining furnace 9 for calcination; the calcined material enters the slag cooler 11 for cooling and is temporarily stored in the receiving silo 13; the waste heat rotary dryer 5 is equipped with a drying furnace water vapor outlet 58, a drying furnace flue gas outlet 59, and a drying furnace waste heat tail gas inlet 56; the water vapor discharged after the material in the waste heat rotary dryer 5 is dried is discharged from the drying furnace water vapor outlet 58, and the generated tail gas is discharged from the drying furnace flue gas outlet 59.

[0041] The high-temperature exhaust gas generated by the calcination and volatilization of the material in the calcination furnace 9 enters the exhaust gas combustion chamber 15 through the exhaust gas volatilization port 95. The high-temperature exhaust gas generated by the combustion of the fuel gas entering the exhaust gas combustion chamber 15 enters the calcination furnace 9 and flows in the opposite direction to the material in the calcination furnace 9, calcining the material in the calcination furnace 9, thus realizing the one-time utilization of the exhaust gas.

[0042] After calcination and heat absorption, the high-temperature exhaust gas becomes low-temperature exhaust gas, which enters the waste heat rotary dryer 5 through the pipeline via the waste heat exhaust gas inlet 56 to dry the material, thus realizing the secondary utilization of the exhaust gas.

[0043] The petroleum coke drying and calcining system provided by this invention has the following advantages compared with the prior art:

[0044] (1) Reduced production costs: Existing technologies directly use natural gas for calcination without preheating and recovery, resulting in high costs per ton. In this solution, the high-temperature exhaust gas emitted during calcination in the calcining furnace 9 is mixed with fuel gas in the exhaust gas combustion chamber 15 and then enters the calcining furnace 9 to calcine the material, achieving primary utilization of the exhaust gas. After absorbing heat during calcination, the high-temperature exhaust gas becomes low-temperature exhaust gas, which then enters the waste heat rotary dryer 5 to dry the material, achieving secondary utilization of the exhaust gas. This waste heat recovery method reduces the consumption of energy such as natural gas, thereby reducing the calcination cost per ton of petroleum coke and facilitating the company's cost control.

[0045] (2) Improve processing efficiency: Existing technologies perform semi-calcination of raw petroleum coke in separate processes, resulting in waste due to inter-process transfers and low processing efficiency due to the lack of production line integration. This technical solution adopts an integrated design, connecting the feeding silo 1, waste heat rotary dryer 5, calcining furnace 9, slag cooler 11, and receiving silo 13 in sequence. The raw petroleum coke raw material flows sequentially between the various devices, realizing continuous operation of drying, calcination, and other processes, reducing waste due to inter-process transfers, improving processing efficiency, and lowering production costs.

[0046] (3) Ensure product quality: Through the reasonable design of the waste heat rotary drying furnace 5 and the calcining furnace 9, and the double utilization of the tail gas, the raw petroleum coke can be dried and calcined under more stable temperature and heat conditions, which helps to ensure the quality of semi-calcined petroleum coke, thus providing high-quality raw materials for the production of artificial graphite with both energy density and rate performance.

[0047] (4) Significant environmental benefits: The system makes full use of exhaust gas, reduces heat loss and environmental pollution caused by direct emission of high-temperature exhaust gas, meets the requirements of energy conservation and environmental protection, and helps enterprises achieve green production.

[0048] This invention effectively solves the problems of low integration, high production cost and low processing efficiency in the prior art by integrating and continuously operating processes such as drying, calcination and cooling, as well as the multiple utilization of exhaust gas.

[0049] The feeding hopper 1 in this application is an open hopper, and its shape can be square, conical, or pyramidal, as long as it meets the functions of feeding and buffering.

[0050] As one implementation method for the rough pretreatment before the waste heat rotary dryer 5, see [link to relevant documentation]. Figure 1 and Figure 2 The process includes: the material in the feeding bin 1 is fed to the double roll crusher 3 below by the vibrating feeder 2 installed at the discharge port of the feeding bin 1, and after being crushed, it enters the double roll crushing bin 4 and falls into the feeding auger 51 of the drying furnace below, and is sent into the waste heat rotary drying furnace 5 for drying.

[0051] Optionally, the installation angle between the vibrating feeder 2 and the feeding bin 1 needs to be specially set. Generally speaking, the screen of the vibrating feeder 2 is inclined at an angle of 20-45° relative to the horizontal plane to ensure the smooth flow of materials.

[0052] The double roll crusher 3 includes a double roll crushing shell and a pair of crushing rolls rotatably installed inside the double roll crushing shell. It can crush the lumpy materials that enter into the shell through collision, friction, and compression, and finally produce powder with a particle size of <20mm. The double roll crusher 3 can be of various forms such as a roller crusher, cone hammer crusher, and pipe crusher.

[0053] Both the feeding hopper 1 and the double roll crusher 3 are installed on the feeding support, and the material can flow from top to bottom under gravity.

[0054] The double-roll crusher hopper 4 is installed below the double-roll crusher 3, and its shape includes, but is not limited to, conical, pyramidal, square, or circular. In this application, the double-roll crusher hopper 4 is conical, with the angle between the generatrix of the conical hopper and the horizontal plane being 45-60°, and a volume of 2m³. 3 .

[0055] As a fine pretreatment before the waste heat rotary dryer 5, see Figure 1 and Figure 8 The process includes: the material in the feeding bin 1 is fed to the double roller crusher 3 below by the vibrating feeder 2 installed at the discharge port of the feeding bin 1; the crushed material is fed into the linear screen feed bin 18 for temporary storage by the crushing and feeding elevator 17; after being screened by the linear screen 19, the large material on the screen enters the waste heat rotary drying furnace 5 for drying via the conveyor belt 20; the undersized material falls onto the linear screen 22 below via the linear discharge screen feed bin 21; the small undersized material after screening falls into the small undersized material bin 24 for temporary storage; and the oversized material screened on the linear discharge screen 22 falls into the oversized material bin 23 for temporary storage.

[0056] In this application, the material crushed by the double roll crusher 3 can fall directly into the crushing and feeding elevator 17 through the guide chute at an angle of 30-45° to the horizontal plane, and be lifted into the linear screen feed hopper 18.

[0057] The linear screen 19 and the direct discharge screen 22 in this application use screen sizes of 10mm and 5mm, respectively. Other sizes can also be used, as long as the particle size range is minimized to ensure the concentration and uniformity of various screened materials. Higher concentration results in higher consistency of the material after calcination. Therefore, this optimized pretreatment method, utilizing materials treated with differentiated screening, significantly improves the yield and uniformity of the calcined material when it enters the drying and calcination system, further enhancing the overall system yield.

[0058] In the above embodiment, the linear screen feed hopper 18 is set to 1m. 3 The reason for the low material storage is the high screening efficiency of the linear screen 19. When screening is required by the linear screen 19, the material can enter it for screening. Only one layer of screen is needed for the linear screen 19, but multiple layers can be set as needed.

[0059] Optionally, the inclination angle of the linear screen 19 is 5-10° (the angle with the horizontal plane).

[0060] To explain, the aforementioned straight discharge screen 22 consists of multiple vibrating screens connected together, sharing a single undersize material bin 24. The straight discharge screen feed bin 21 is equipped with conical discharge ports corresponding to different vibrating screens. In this application, the straight discharge screen feed bin 21 has two conical discharge ports, corresponding to two vibrating screens.

[0061] In some embodiments, see Figure 1 and Figure 2 The waste heat exhaust gas inlet 56 is located near the discharge port 57 of the waste heat rotary dryer 5, while the steam outlet 58 and the flue gas outlet 59 are located near the feed inlet of the waste heat rotary dryer 5. This design allows the hot airflow entering the waste heat rotary dryer 5 to flow in the opposite direction to the material, thus improving the drying effect.

[0062] The hot airflow can be introduced into the waste heat rotary dryer 5 by the induced draft fan 16, and the final exhaust gas in the waste heat rotary dryer 5 can also be drawn out from the exhaust port 59 of the dryer by the induced draft fan 16. It should be noted that the setting of the induced draft fan 16 is a conventional technical means. The induced draft fans 16 set in different positions in this application are not labeled one by one, nor are they shown in the figure one by one.

[0063] The waste heat rotary dryer 5 of this application includes an outer cylinder 591 and an inner cylinder 54 built into the outer cylinder 591, which together form a heating chamber 55. The material flows in the inner cylinder 54 and is heated and dried.

[0064] The waste heat exhaust gas inlet 56 of the drying furnace is located on the outer cylinder 591 of the drying furnace and enters the heating chamber 55 of the drying furnace; the water vapor outlet 58 of the drying furnace is located on the inner cylinder 54 of the drying furnace to facilitate the discharge of water vapor; and the exhaust gas outlet 59 of the drying furnace is located on the outer cylinder 591 of the drying furnace to facilitate the discharge of exhaust gas after secondary use.

[0065] The two ends of the inner cylinder 54 of the drying oven extend beyond the outer cylinder 591 of the drying oven and are driven to rotate by the drying oven rotation drive mechanism to improve the uniformity of material drying and improve the production quality and efficiency of the material.

[0066] The drying oven rotation drive mechanism includes a drying oven drive motor 52, a drive gear mounted on the main shaft of the drying oven drive motor 52, a gear ring surrounding the inner cylinder 54 of the drying oven, and drying oven support wheels 53 supported at both ends of the inner cylinder 54 of the drying oven. The rotation of the inner cylinder 54 of the drying oven is achieved by driving the drying oven drive motor 52.

[0067] The drive gear and the gear ring constitute the transmission mechanism; chain drive or belt drive can also be used here.

[0068] In some embodiments, see Figure 1 and Figure 3A feeding mechanism 6 is provided between the waste heat rotary dryer 5 and the calcining furnace 9. The feeding mechanism 6 includes a pit elevator 61 connected to the dryer discharge port 57 of the waste heat rotary dryer 5, an above-ground elevator 62 connected to the pit elevator 61, a calcining feed bin 7 for temporarily storing the material lifted by the above-ground elevator 62, and a calcining feed conveyor 8 for sending the material into the calcining furnace 9.

[0069] The feeding mechanism 6 consists of a pit elevator 61 and an above-ground elevator 62 working together to avoid the inconvenience of maintenance due to the large size of a single elevator. Alternatively, the elevator can be a bucket elevator or a conveyor belt 20, etc. The calcination feed hopper 7 can be in various shapes such as round, square, or conical, as long as it meets the buffering function.

[0070] To facilitate the smoother flow of dried petroleum coke raw material from the calcination feed hopper 7 into the calcination feed conveyor 8, a vibration device, such as a vibrating electric hammer, a vibrating air hammer, or an activation hopper, can be installed at the bottom of the calcination feed hopper 7. By vibrating, the material is activated, which can effectively eliminate the arching, blockage, and sticking of the dried petroleum coke raw material containing a certain amount of moisture, thereby solving the problem of difficult material discharge from the hopper.

[0071] The dried material, shaken off from the calcination feed hopper 7 onto the calcination feed conveyor 8, is then transported to the calcination feed inlet 91 of the calcination furnace 9 via the calcination feed conveyor 8. The calcination feed conveyor 8 can be a conventional transmission method such as a conveyor belt 20 or a conveyor auger, which sends the dried material into the calcination furnace 9 for calcination. The specific form can be adjusted according to the on-site working conditions.

[0072] In some embodiments, see Figure 1 , Figure 4 and Figure 5 The calcining furnace 9 includes a calcining shell 98, a calcining heating pipe 96 coaxially fitted inside the calcining shell 98, and a ring of calcining material pipes 97 disposed between the calcining heating pipe 96 and the calcining shell 98. A calcining furnace exhaust gas vent 95 is disposed on the calcining material pipe 97. High-temperature exhaust gas enters from the end of the calcining heating pipe 96 near the calcining discharge port 94, and after calcination and cooling, exits from the end of the calcining heating pipe 96 near the calcining feed port 91, entering the waste heat rotary drying furnace 5. The calcining furnace exhaust gas vent 95 is connected to the exhaust gas combustion chamber 15 via the combustion chamber inlet pipe 152.

[0073] In some embodiments, see Figure 1 An emergency vent 99 is provided on the high-temperature gas outlet pipe 153 of the incineration chamber, which connects the exhaust gas incineration chamber 15 to the calcination heating pipe 96. When the calcination furnace 9 malfunctions or an accident occurs, emergency gas can be released through the emergency vent 99 to prevent more serious malfunctions.

[0074] In some embodiments, see Figure 1 The calcining furnace 9 is arranged at an angle of 5-10° with the horizontal plane, and the calcining discharge port 94 is lower than the calcining feed port 91.

[0075] In some embodiments, see Figure 1 and Figure 4 A calcining furnace 9 is equipped with a calcining rotary drive mechanism. Calcination support wheels 92 are located at both ends of the calcining furnace 9. The calcining rotary drive mechanism includes a calcining drive motor 93, a drive gear mounted on the main shaft of the calcining drive motor 93, and a gear ring mounted around the calcining furnace 9. The gear ring meshes with the drive gear. The drive gear and gear ring here have the same structure as the drive gear and gear ring in the aforementioned drying furnace rotary drive mechanism, only differing in the number of teeth. This is a conventional gear transmission configuration and will not be distinguished in the text or labeled in the figures.

[0076] In some embodiments, see Figure 1 , Figure 6 and Figure 7 The slag cooler 11 is equipped with a slag inlet 111, and below the slag inlet 111 is a clearing port 112 for unblocking material. Below the clearing port 112 is an emergency discharge port 113. When the slag cooler 11 is blocked, the material can be cleared through the clearing port 112 to ensure the continuous forward flow of the calcined material. In addition, if the slag cooler 11 malfunctions or the calcining furnace 9 experiences an accident, the material can be discharged urgently through the emergency discharge port 113 to prevent further damage.

[0077] Combination Figure 1 As shown, the process flow of the petroleum coke drying and calcining system provided by the present invention is as follows:

[0078] Step 1, Feeding

[0079] The raw petroleum coke is fed into the feeding hopper 1 through the feeding port above the feeding hopper 1.

[0080] At startup, the raw petroleum coke in the feeding hopper 1 is fed evenly into the double-roll crusher 3 at a certain speed via the vibrating feeder 2 located below the feeding hopper 1. The purpose of placing the vibrating feeder 2 is to ensure the uniformity and stability of material conveying and to prevent abnormalities such as material blockage in the crusher. Therefore, the installation angle between the vibrating feeder 2 and the feeding hopper 1 needs to be specially set to ensure smooth material flow. Generally, the inclination angle of the vibrating feeder 2 is set to 20-45°.

[0081] Step 2, see Figure 1 , Figure 2 and Figure 8 Preprocessing

[0082] It includes two processes: rough pretreatment and fine pretreatment. Depending on production needs, only the rough pretreatment process can be selected, or both pretreatment processes can be performed simultaneously.

[0083] Coarse pretreatment: The material enters the double roll crusher 3, which has two crushing rolls inside. Driven by the crushing drive motor, the rolls rotate and crush the lumpy material inside through collision, friction, and compression, ultimately producing powder with a particle size of <20mm. The production line is designed so that the capacity of the front-end equipment is greater than that of the back-end equipment. Therefore, a double roll crushing hopper 4 is installed below the double roll crusher 3, which has the function of material storage and smooth material flow to the back end.

[0084] The material after being crushed by the double roll crusher 3 enters the waste heat rotary dryer under the action of gravity through the double roll crushing hopper 4 for drying, thus completing the coarse pretreatment.

[0085] Fine pretreatment: In order to improve the overall system yield and reduce the amount of fine powder entering the tail gas incineration chamber 15 for combustion, as an optimized pretreatment method, the material that has undergone coarse pretreatment needs to be finely pretreated.

[0086] The specific process is as follows: The material after being crushed by the double roll crusher 3 does not go directly into the waste heat rotary dryer through the double roll crushing hopper 4 for drying. After crushing, the material is first transported to the linear screen feed hopper 18 for temporary storage through the crushing feeding elevator 17. When needed, it is screened through the linear screen 19 with a screen size of 10mm.

[0087] Larger particles (10-20mm) sieved by linear screen 19 can be conveyed via belt 20 into a waste heat rotary dryer for drying. This results in more uniform material flow into the production line with less fine powder, significantly improving material yield. Furthermore, the more uniform and concentrated particle size leads to smaller variations in the properties of the calcined material.

[0088] Material particles between 0-10mm fall into the feed hopper 21 of the direct discharge screen for temporary storage. The volume and shape of the feed hopper 21 are not specifically limited; it can be designed as follows: Figure 1 The biconical type shown has a volume of 5m³. 3 Other types can also be used. Then, the material can enter the direct discharge screen 22 for screening. Here, the direct discharge screen 22 also has only one layer of screen, and the screen size is 5mm.

[0089] Materials of 0-5mm enter the undersize material bin 24. This type of material is fine powder and is not recommended for reuse in this calcination system. It is recommended to carry out other processing, such as direct grinding or selling. Materials of 5-10mm that pass through the direct discharge screen 22 enter the oversize material bin 23. This type of material is medium-sized particles. After temporary storage, it can enter the waste heat rotary dryer according to this batch type. Its principle is the same as that of 10-20mm particles.

[0090] Based on this, when the material after differential screening enters the drying and calcining system, the yield is significantly improved, and the consistency of the material after calcination is significantly enhanced.

[0091] Step 3, see Figure 1 and Figure 2 ,drying

[0092] The main working principle of the waste heat rotary dryer 5 is as follows: the coarsely crushed material enters the inner cylinder 54 of the dryer through the feed auger 51. The dryer drive motor 52 drives the inner cylinder 54 to roll continuously on the dryer support wheel 53, thereby causing the material inside the inner cylinder 54 to flow forward along the spiral until the material is dried and flows out through the discharge port 57. Since petroleum coke raw materials generally contain 5-10% moisture, during the drying process, the moisture is discharged through the water vapor outlets designed at both ends of the waste heat rotary dryer 5 to ensure the drying effect and the internal pressure of the inner cylinder.

[0093] The waste heat rotary drying oven 5 is horizontally positioned, and the inner cylinder 54 of the drying oven is also horizontally positioned. The drying temperature here is 280-320℃, and the heat resistance temperature of each component of the waste heat rotary drying oven 5 should be higher than 500℃ to ensure the normal operation of the equipment and prevent it from being damaged by heat.

[0094] It should be noted that the waste heat rotary drying oven 5 in this application is a commonly used industrial drying equipment, also known as a rotary dryer. Rotary dryers are widely used in industries such as chemical, pharmaceutical, food, electronics, and metallurgy. They achieve efficient drying by ensuring the material is heated evenly within the rotating drum. Their working principle is based on the counter-current or co-current contact between hot air and the material, using conduction, convection, and radiation to evaporate and remove moisture from the material.

[0095] This application provides Figure 9 The internal structure of the waste heat rotary dryer 5 is shown. The inner wall of the inner cylinder 54 of the dryer, which is a rotating component, is provided with spiral blades 541. The spiral blades extend along the length of the inner cylinder 54. The dryer drive motor 52 drives the inner cylinder 54 of the dryer to rotate, so that the material inside the inner cylinder 54 of the dryer flows forward in a spiral and flows out from the discharge port 57 of the dryer.

[0096] The drying principle of the waste heat rotary dryer is as follows: the low-temperature exhaust gas discharged from the calcining furnace 9 enters the heating chamber 55 of the dryer through the waste heat exhaust gas inlet 56, and dries the material inside through the inner cylinder 54 of the dryer which has high thermal conductivity. After the heat energy of the exhaust gas is continuously dissipated, it is discharged through the exhaust port 59 of the dryer by the induced draft fan 16. At the same time, the outer cylinder 591 of the waste heat rotary dryer 5 should have a heat preservation function and can be filled with refractory fiber cotton, etc., to ensure that more of the heat energy of the exhaust gas is put into the drying of the material and reduce its continuous loss through the shell.

[0097] After drying, the raw petroleum coke leaves the waste heat rotary dryer and is transported by the pit elevator 61 and the ground elevator 62 to the calcination feed silo 7 for temporary storage, to be used in the next process.

[0098] Step four, see Figure 1 , Figures 3 to 5 calcination

[0099] The dried material temporarily stored in the calcination feed hopper 7 is vibrated and falls into the calcination feed conveyor 8, which is then transported to the calcination furnace 9 for calcination.

[0100] The calcining furnace 9 rotates continuously under the drive of the calcining drive motor 93, ensuring that the calcined material flows along the calcining material pipe 97 inside the calcining furnace 9 towards the tail end of the calcining furnace 9 under its own gravity. The calcining drive motor 93 adopts a frequency conversion design, which can be set with different frequencies so that the calcining furnace 9 can rotate at different speeds, thereby adjusting the production cycle of the material.

[0101] Generally, to ensure the calcination effect of the material in the calcining furnace 9, the overall flow time from feeding into the calcining inlet 91 to discharging into the calcining outlet 94 is controlled to be approximately 10 hours. The material flows in the calcining material pipeline 97 surrounding the calcining heating pipeline 96, and there is no direct contact between the material and the calcining heating pipeline 96 to prevent safety accidents such as explosions and deflagrations.

[0102] Step 5, see Figure 1 and Figure 6 Calcination for heating - drying for heating, also known as exhaust gas incineration and reuse.

[0103] A tail gas evaporation port 95 is installed above the tail end of the calcining furnace 9. During the calcination process, the volatiles volatilized from the material enter the tail gas combustion chamber 15 through the tail gas evaporation port 95. The principle of material volatilization is as follows: raw coke contains 8% to 15% volatiles, including light hydrocarbons, moisture, and some sulfur- and nitrogen-containing compounds. When the raw coke is heated to a temperature range of approximately 600°C to 900°C, these volatiles undergo a violent thermal decomposition reaction and are released from the solid coke.

[0104] When the volatiles released during calcination of the material enter the tail gas combustion chamber 15 through the tail gas evaporation port 95 of the calciner and the inlet pipe 152 of the combustion chamber, they are mixed and burned with natural gas introduced through the natural gas inlet 151 of the combustion chamber. Because the volatiles in petroleum coke have a high calorific value, only a small amount of natural gas is needed for combustion support when the entire system is continuously feeding and discharging material. Of course, at the beginning of production, a large amount of natural gas is required to ensure that the material initially releases volatiles into the tail gas combustion chamber 15 to achieve the desired calcination effect. The amount of natural gas used can then be gradually reduced based on the release of volatiles. Ultimately, due to the continuous release and combustion of volatiles during continuous operation, the system's operating energy cost is very low.

[0105] The exhaust gas incineration chamber 15 is equipped with burners and a combustion fan to facilitate the combustion of natural gas and volatiles. The exhaust gas, carrying significant heat energy, flows through the incineration chamber outlet pipe and, driven by the system's induced draft fan 16, enters the calcination heating pipe 96 to calcine the materials inside the calcination furnace 9. The calcination temperature provided by this heat energy can reach over 800℃. Simultaneously, the calcination furnace 9 is equipped with thermocouples for temperature monitoring to ensure the stability and adjustability of the calcination temperature.

[0106] As mentioned above, there is no direct contact between the exhaust gas carrying a large amount of heat and the material. Driven by the induced draft fan 16, the high-temperature exhaust gas carrying heat flows in the opposite direction to the material. After passing through the high-temperature exhaust pipe 153 of the incineration chamber and entering the calcination heating pipe 96, the low-temperature exhaust gas, after exchanging heat with the material, directly enters the waste heat exhaust gas inlet 56 of the drying furnace, so as to provide heat for the waste heat rotary dryer 5 to dry the material.

[0107] Finally, the exhaust gas, which continuously loses heat, leaves the entire petroleum coke drying and calcining system via induced draft fan 16 and is discharged from the chimney after environmental treatment.

[0108] Step Six, see Figure 6 Cooling storage

[0109] The material calcined in the calcining furnace 9 leaves the calcining furnace 9 through the calcining discharge valve 10 located at the calcining discharge port 94. Since the temperature of the calcined material is high at this time, the calcining furnace 9 and the calcining discharge valve 10 must be made of high-temperature resistant materials, such as stainless steel 310S, with a heat resistance temperature of at least 1200℃.

[0110] After calcination, the material enters the slag cooler 11 through the calcination discharge valve 10 for material cooling. The material flows forward continuously in the spiral cylinder of the slag cooler 11 along the direction of spiral rotation. Circulating cooling water is circulated outside the spiral cylinder to continuously cool the material inside.

[0111] After being cooled by the slag cooler 11, the material is conveyed by the bucket elevator 12 to the receiving hopper 13 for temporary storage. At this time, the temperature of the cooled material is below 40℃, and it can be safely stored in the receiving hopper 13.

[0112] Similar to the aforementioned silos, the shape and volume of the receiving silo 13 are not limited, as long as they meet the requirements of system operation. When it is necessary to utilize the raw materials after drying, calcination, and cooling, they can be packaged and tonned through the discharge valve 14 at the bottom of the receiving silo 13, facilitating subsequent process transfer and use.

[0113] In this application, the receiving hopper 13 is conical in shape, with a volume of 5.8 m³. 3 An inclined chute with an inclination angle of 35-45° is provided between the bucket elevator 12 and the receiving bin 13.

[0114] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0115] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A petroleum coke drying and calcination system, characterized in that, include: The feeding bin (1), waste heat rotary dryer (5), calcining furnace (9), slag cooler (11) and receiving bin (13) are connected in sequence, and also include a tail gas incineration chamber (15) connected to the calcining furnace (9); The raw petroleum coke is fed into the feeding hopper (1), and after pretreatment, it is sent into the waste heat rotary dryer (5) for drying; the material dried in the waste heat rotary dryer (5) enters the calcining furnace (9) for calcination; the calcined material enters the slag cooler (11) for cooling and is temporarily stored in the receiving hopper (13); The waste heat rotary dryer (5) is provided with a drying furnace water vapor outlet (58), a drying furnace flue gas outlet (59) and a drying furnace waste heat exhaust gas inlet (56); the water vapor discharged after the material in the waste heat rotary dryer (5) is dried is discharged from the drying furnace water vapor outlet (58), and the exhaust gas generated is discharged from the drying furnace flue gas outlet (59). The high-temperature exhaust gas generated by the calcination of the material in the calcining furnace (9) enters the exhaust gas combustion chamber (15) through the exhaust gas evaporation port of the calcining furnace (9). It mixes and burns with the fuel gas entering the exhaust gas combustion chamber (15) to generate high-temperature exhaust gas, which then enters the calcining furnace (9) and flows in the opposite direction to the material in the calcining furnace (9), calcining the material in the calcining furnace (9) and realizing the one-time utilization of the exhaust gas. The high-temperature exhaust gas is calcined and absorbs heat to form low-temperature exhaust gas, which enters the waste heat rotary dryer (5) through the pipeline via the waste heat exhaust gas inlet (56) of the dryer to dry the material, thereby realizing the secondary utilization of the exhaust gas.

2. The petroleum coke drying and calcining system as described in claim 1, characterized in that, The pretreatment before the waste heat rotary dryer (5) includes coarse pretreatment, which includes: the material in the feeding bin (1) is fed to the roller crusher (3) below by the vibrating feeder (2) installed at the discharge port of the feeding bin (1), and after being crushed, it enters the roller crushing bin (4) and falls into the drying furnace feeding auger (51) below, and is sent into the waste heat rotary dryer (5) for drying.

3. The petroleum coke drying and calcining system as described in claim 1, characterized in that, The pretreatment before the waste heat rotary dryer (5) includes fine pretreatment, which includes: the material in the feeding bin (1) is fed to the double roller crusher (3) below by the vibrating feeder (2) installed at the discharge port of the feeding bin (1), the crushed material is fed into the linear screen feeding bin (18) by the crushing feeding elevator (17) for temporary storage, and after being screened by the linear screen (19), the large material on the screen enters the waste heat rotary dryer (5) for drying through the conveyor belt line (20), the undersize material falls to the linear screen (22) below through the linear discharge screen feeding bin (21), the undersize small material after screening falls into the undersize small material bin (24) for temporary storage, and the oversize material screened on the linear discharge screen (22) falls into the oversize material bin (23) for temporary storage.

4. The petroleum coke drying and calcining system as described in claim 1, characterized in that, The waste heat exhaust gas inlet (56) of the drying furnace is located at one end of the drying furnace discharge port (57) near the waste heat rotary drying furnace (5), and the water vapor outlet (58) and the exhaust port (59) of the drying furnace are located at the end of the drying furnace feed port near the waste heat rotary drying furnace (5).

5. The petroleum coke drying and calcining system as described in claim 1, characterized in that, A feeding mechanism (6) is provided between the waste heat rotary dryer (5) and the calcining furnace (9). The feeding mechanism (6) includes a pit elevator (61) connected to the drying furnace discharge port (57) of the waste heat rotary dryer (5), an above-ground elevator (62) connected to the pit elevator (61), a calcining feed bin (7) for temporarily storing the material lifted by the above-ground elevator (62), and a calcining feed conveyor (8) for sending the material into the calcining furnace (9).

6. The petroleum coke drying and calcining system as described in claim 1, characterized in that, The calcining furnace (9) includes a calcining shell (98), a calcining heating pipe (96) coaxially fitted inside the calcining shell (98), and a ring of calcining material pipes (97) disposed between the calcining heating pipe (96) and the calcining shell (98); the tail gas evaporation port of the calcining furnace (9) is disposed on the calcining material pipe (97); the high-temperature tail gas enters from the end of the calcining heating pipe (96) near the calcining discharge port (94), and after calcination and cooling, it is discharged from the end of the calcining heating pipe (96) near the calcining feed port (91) and enters the waste heat rotary drying furnace (5).

7. The petroleum coke drying and calcining system as described in claim 6, characterized in that, An emergency vent (99) is provided on the high-temperature gas outlet pipe (153) of the incineration chamber (15) which is connected to the calcination heating pipe (96).

8. The petroleum coke drying and calcining system as described in claim 6, characterized in that, The calcining furnace (9) is arranged at an angle of 5-10° with respect to the horizontal plane, and the calcining discharge port (94) is lower than the calcining feed port (91).

9. The petroleum coke drying and calcining system as described in claim 1, characterized in that, A calcining rotary drive mechanism is provided outside the calcining furnace (9), and calcining support wheels (92) are respectively provided at both ends of the calcining furnace (9); the calcining rotary drive mechanism includes a calcining drive motor (93), a drive gear installed on the main shaft of the calcining drive motor (93), and a gear ring installed around the calcining furnace (9), the gear ring meshing with the drive gear.

10. The petroleum coke drying and calcining system as described in claim 1, characterized in that, The slag cooler (11) is provided with a slag inlet (111), and a slag drain (112) for clearing blockages is provided below the slag inlet (111). An emergency discharge port (113) is provided below the slag drain (112).

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