A multi-stage petroleum coke calcining equipment

Abstract

This invention belongs to the field of petroleum coke calcination production technology, specifically relating to a multi-stage petroleum coke calcination equipment. By modifying the kiln structure, the preheating zone and calcination zone are separated into two different kilns, each with its own suitable operating mode to achieve the required calcination temperature. This not only avoids the problem of incomplete utilization of volatiles generated in the same kiln, extending the kiln's lifespan, but also ensures stable kiln operation and increases production capacity. Furthermore, the high-temperature calcined petroleum coke is pre-cooled before entering the cooling kiln for further cooling, reducing both cooling water usage and dust generation.

Description

Technical Field

[0001] The invention belongs to the technical field of calcination production of petroleum coke, and in particular relates to a multi-stage petroleum coke calcination device. Background Art

[0002] The existing petroleum coke calcining equipment includes rotary kilns and tank furnaces, and usually adopts the "preheat zone + calcining zone" method to complete the multi-stage calcination of petroleum coke. For the rotary kiln, the position and temperature of the calcining zone determine the quality of calcination. The moving speed of the petroleum coke in the rotary kiln directly affects the position of the calcining zone. For example, if the petroleum coke moves too fast in the rotary kiln, the petroleum coke will stay in the rotary kiln for a short time, and the preheat zone will be relatively elongated, causing the calcining zone to move forward.

[0003] If the calcining zone is too far forward, ring formation will occur at the tail of the kiln, which will also affect the life of the rotary kiln lining; if the calcining zone is too far back, the volatiles discharged from the petroleum coke are not fully burned in the kiln, and the unburned volatiles still have a very high temperature, which will affect the life of the flue lining and fail to make full use of the volatiles.

[0004] At present, the main method for moving the calcining zone is to control the air supply. When the calcining zone is found to be seriously moved forward, the tertiary air and secondary air are appropriately increased, and the kiln head door is appropriately opened, so that the volatile matter in the front section cannot be fully burned, the temperature in the front section is reduced, and the volatile matter is burned in large quantities in the back section, increasing the temperature, so that the calcining zone gradually moves backward. When the calcining zone is found to be seriously moved backward, the tertiary air volume is appropriately reduced, the secondary air volume is reduced, and the kiln head door is appropriately closed, so that the volatile matter and air can be fully mixed in the front section and fully burned, thereby increasing the temperature in the front section to achieve the forward movement of the calcining zone.

[0005] However, adjusting the calcining zone of the rotary kiln by controlling the air supply often causes unstable working conditions in the calcining zone, thus affecting the quality of calcined coke.

[0006] In addition, the high-temperature petroleum coke produced by the rotary kiln directly enters the cooling kiln for cooling. The cooling process not only consumes a large amount of cooling water to achieve, but also directly spraying cooling water for cooling will aggravate the pulverization of the calcined coke, which is not conducive to the subsequent forming of ingredients. Therefore, how to reduce the consumption of cooling water from the source can truly solve the fundamental problem and achieve the purpose of reducing costs and increasing efficiency. Summary of the invention

[0007] In order to make up for the deficiencies mentioned in the background technology, the present invention provides a multi-stage petroleum coke calcining equipment.

[0008] The technical solution of the present invention is as follows:

[0009] The present invention provides a multi-stage petroleum coke calcining device, comprising a first kiln body, a second kiln body and a cooling kiln connected in sequence;

[0010] A preheating zone is arranged inside the first kiln body along the material moving direction, a first fire channel is arranged circumferentially of the preheating zone, an inlet of the first fire channel is connected to a first fan, and an outlet of the first fire channel is connected to a volatile matter collecting bin;

[0011] A calcining zone and a precooling zone are sequentially arranged inside the second kiln body along the material moving direction, a second fire channel is arranged circumferentially on the calcining zone, one end of the second fire channel is connected to the volatile matter collecting bin, and an air channel is arranged circumferentially on the precooling zone, one end of the air channel is connected to the second fan, and the other end is connected to the second fire channel;

[0012] When the first kiln body is working, the petroleum coke is heated to the preheating temperature in the preheating zone of the first kiln body, generating a large amount of volatiles. The volatiles enter the first fire channel under the action of negative pressure and are divided in the first fire channel. One part is used for combustion to heat the preheating zone, and the other part is collected in the volatile collection bin.

[0013] The preheated petroleum coke first enters the calcination zone of the second kiln body, and is calcined at high temperature to obtain high-temperature calcined petroleum coke. The high-temperature calcined petroleum coke enters the precooling zone of the second kiln body for preliminary cooling. The second fan blows cold air into the air channel. The cold air in the air channel exchanges heat with the high-temperature calcined petroleum coke in the precooling zone to obtain preliminarily cooled petroleum coke and preheated air. The preheated air in the air channel enters the second fire channel connected to the air channel, and is mixed and burned with volatiles from the volatile collection bin to heat the calcination zone to the calcination temperature.

[0014] The cooling kiln is used for the petroleum coke to enter after preliminary cooling for cooling.

[0015] The outlet of the first fire channel is connected to the volatile matter collecting bin via an induced draft fan.

[0016] The first fire channel is provided with a volatile matter regulating valve for controlling the volatile matter content entering the volatile matter collecting bin.

[0017] The preheating zone is also provided with a first fuel adding port, which is communicated with the first fire channel.

[0018] The second fire channel is provided with an air regulating valve, and the opening of the air regulating valve is controlled to match the preheated air with the volatile content from the volatile collection bin.

[0019] The calcining zone is also provided with a second fuel adding port, which is communicated with the second fire channel.

[0020] The cooling kiln is a drum-type cooler, which is provided with a direct cooling pipe inside for directly spraying cooling water on the pre-cooled material, and an indirect cooling pipe outside for cooling the drum wall.

[0021] The material discharge port of the first kiln body is connected to the material feed port of the second kiln body via an electric slide pipe, and the material discharge port of the second kiln body is connected to the material feed port of the cooling kiln via an electric slide pipe.

[0022] The first kiln body, the second kiln body and the cooling kiln are all inclined at 3-6 degrees from the horizontal.

[0023] Beneficial effects: The present invention changes the kiln structure, and realizes the preheating zone and the calcining zone through two kiln bodies respectively, and each kiln body has its own adaptive working mode to meet the calcining temperature requirements, which can not only avoid the problem that the volatile matter generated in the same kiln body cannot be fully utilized, extend the life of the kiln body, but also ensure the stable operation of the kiln body and expand the production volume. In addition, the high-temperature calcined petroleum coke is precooled before entering the cooling kiln for cooling, which can reduce the use of cooling water and reduce the generation of dust.

[0024] The present invention allows the volatiles generated in the first kiln body to escape to the first fire channel under the action of negative pressure and be diverted in the first fire channel, with one part being used to supply the heat source for the preheating zone and the other part being collected to supply the heat source for the calcining zone of the second kiln body, thereby realizing the reasonable and full utilization of the volatiles.

[0025] In the second kiln body of the present invention, the preheated air generated by the heat exchange of the high-temperature calcined petroleum coke with the blown cold air works together with the volatile matter from the volatile matter collecting bin to burn and generate heat to achieve calcination of the petroleum coke. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic structural diagram of a multi-stage petroleum coke calcining equipment provided in an embodiment of the present invention.

[0027] Description of reference numerals:

[0028] 1. First kiln body, 11. Preheating zone, 12. First fire channel, 13. Volatile matter collecting bin, 14. First fuel adding port, 2. Second kiln body, 21. Calcination zone, 22. Precooling zone, 23. Second fire channel, 24. Air channel, 25. Second fuel adding port, 3. Cooling kiln. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0030] Embodiment: A multi-stage petroleum coke calcining device comprises a first kiln body 1, a second kiln body 2 and a cooling kiln 3 connected in sequence;

[0031] A preheating zone 11 is arranged inside the first kiln body 1 along the material moving direction, a first fire channel 12 is arranged circumferentially of the preheating zone 11, a first fan is connected to the inlet of the first fire channel 12, and a volatile matter collecting bin 13 is connected to the outlet of the first fire channel 12;

[0032] A calcining zone 21 and a precooling zone 22 are sequentially arranged inside the second kiln body 2 along the material moving direction. A second fire channel 23 is circumferentially arranged on the calcining zone 21, and one end of the second fire channel 23 is connected to the volatile matter collecting bin 13. An air channel 24 is circumferentially arranged on the precooling zone 22, and one end of the air channel 24 is connected to the second fan, and the other end is connected to the second fire channel 23.

[0033] The specific working mode of the calcining equipment is:

[0034] When the first kiln body 1 is working, the petroleum coke is heated to a preheating temperature, such as 500-800°C, in the preheating zone 11 of the first kiln body 1, and a large amount of volatiles are generated. The volatiles enter the first fire channel 12 under the action of negative pressure, and are divided in the first fire channel 12. One part is used for combustion to heat the preheating zone 11, and the other part is collected in the volatile collection bin 13.

[0035] The preheated petroleum coke first enters the calcination zone 21 of the second kiln body 2, and is calcined at high temperature to obtain high-temperature calcined petroleum coke. The high-temperature calcined petroleum coke enters the precooling zone 22 of the second kiln body 2 for preliminary cooling. The second fan blows cold air into the air channel 24. The cold air in the air channel 24 exchanges heat with the high-temperature calcined petroleum coke in the precooling zone 22 to obtain preliminarily cooled petroleum coke and preheated air. The preheated air in the air channel 24 enters the second fire channel 23 connected to the air channel 24, and is mixed and burned with the volatile matter from the volatile matter collecting bin 13 to heat the calcination zone 21 to the calcination temperature, such as above 1250°C.

[0036] The cooling kiln 3 is used for the petroleum coke to enter after preliminary cooling for cooling.

[0037] The present invention changes the kiln structure, and realizes the preheating zone and the calcining zone through two kiln bodies respectively, and each kiln body has its own adaptive working mode to achieve the calcining temperature requirement, which can not only avoid the problem that the volatile matter generated in the same kiln body cannot be fully utilized, extend the life of the kiln body, but also ensure the stable operation of the kiln body and expand the production volume. In addition, the high-temperature calcined petroleum coke is precooled before entering the cooling kiln for cooling, which can reduce the use of cooling water and reduce the generation of dust.

[0038] Given that the calcination quality of petroleum coke is closely related to the calcination temperature, and different calcination temperatures will affect the changes in the components of petroleum coke, for example, when the calcination temperature is less than 400°C, the macromolecules in the petroleum coke are mainly cracked into small molecules, causing some side chain groups to break; at 500-800°C, the petroleum coke shrinks and densifies, and the components of the volatile matter are hydrocarbons, mainly hydrogen and methane; at greater than 1250°C, the petroleum coke will form a planar network of carbon atoms with an ordered arrangement structure in two-dimensional space.

[0039] Therefore, when the heat generated by the combustion of volatiles is used as a heat source, it needs to be reasonably utilized, mainly in two aspects. First, the volatiles in the preheating zone 11 escape to the first fire channel 12 under the action of negative pressure, and are diverted in the first fire channel 12, one part is used for the heat source supply of the preheating zone 11, and the other part is collected to supply the heat source for the calcining zone 21 of the second kiln body 2. In order to ensure that the volatiles generated by the petroleum coke in the first kiln body 1 in the preheating zone 11 are fully escaped, preferably, the outlet of the first fire channel 12 is connected to the volatile collection bin 13 via an induced draft fan.

[0040] Furthermore, a volatile matter regulating valve is provided on the first fire channel 12 to control the content of volatile matter entering the volatile matter collecting bin 13, so as to better achieve the purpose of diversion.

[0041] In actual operation, the first kiln body 1 can be heated by external fuel when it is activated. Therefore, the preheating zone 11 is further provided with a first fuel adding port 14 , which is connected to the first fire channel 12 .

[0042] The second kiln body 2 is mainly used to calcine petroleum coke and pre-cool the high-temperature calcined petroleum coke. The preheated air generated by the heat exchange of the high-temperature calcined petroleum coke with the cold air blown in works together with the volatile matter from the volatile matter collection bin 13 to burn and generate heat to achieve the calcination of petroleum coke.

[0043] Preferably, an air regulating valve is provided on the second fire channel 23 , and the opening of the air regulating valve is controlled to match the preheated air with the volatile content from the volatile collection bin 13 .

[0044] In addition, in order to ensure sufficient supply of heat source, in addition to using the heat generated by the combustion of volatiles in the volatile collection bin 13 as the heat source, external fuel can also be added when necessary. For this purpose, a second fuel addition port 25 is also provided on the calcination zone 21, and the second fuel addition port 25 is connected to the second fire channel 23.

[0045] Regarding the cooling kiln, since the high-temperature calcined petroleum coke has been pre-cooled, the cooling kiln does not require high-intensity cooling water spraying and large-scale supply, which can not only reduce the generation of dust, but also reduce the quality problems caused by cooling of the calcined petroleum coke.

[0046] Specifically, the cooling kiln 3 is a drum-type cooler, which is provided with a direct cooling pipe capable of directly spraying cooling water on the pre-cooled material, and an indirect cooling pipe for cooling the drum wall. During the operation of the cooling kiln 3, a combination of direct cooling and indirect cooling is used to cool the petroleum coke to below 70°C to meet the discharge requirements. A circulating material guide channel can also be added between the cooling material transfer bin at the cooling kiln outlet and the cooling kiln entrance to guide the stored cold material back to the cooling kiln entrance to mix with the material to be cooled, and the temperature can be quickly reduced by means of the rotation speed of the cooling kiln and the heat transfer between the cold and hot materials, so as to further control water and reduce consumption.

[0047] In addition, the discharge port of the first kiln body 1 is connected to the feed port of the second kiln body 2 via an electric slide pipe, and the discharge port of the second kiln body 2 is connected to the feed port of the cooling kiln 3 via an electric slide pipe. This connection method facilitates automation during maintenance.

[0048] In the multi-stage petroleum coke calcining equipment, the first kiln body 1, the second kiln body 2 and the cooling kiln 3 are all inclined at a horizontal angle of 3-6 degrees, so that the petroleum coke completes the corresponding reaction in the process of gradually moving from the kiln tail to the kiln head.

[0049] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A multi-stage petroleum coke calcining equipment, characterized in that: It comprises a first kiln body (1), a second kiln body (2) and a cooling kiln (3) which are connected in sequence; A preheating zone (11) is arranged inside the first kiln body (1) along the material moving direction, a first fire channel (12) is arranged circumferentially around the preheating zone (11), an inlet of the first fire channel (12) is connected to a first fan, and an outlet of the first fire channel (12) is connected to a volatile matter collecting bin (13); The first fire channel (12) is provided with a volatile matter regulating valve for controlling the volatile matter content entering the volatile matter collecting bin (13); A calcining zone (21) and a precooling zone (22) are sequentially arranged inside the second kiln body (2) along the material moving direction; a second fire channel (23) is arranged circumferentially on the calcining zone (21); one end of the second fire channel (23) is connected to the volatile matter collecting bin (13); an air channel (24) is arranged circumferentially on the precooling zone (22); one end of the air channel (24) is connected to the second fan, and the other end is connected to the second fire channel (23); The second fire channel (23) is provided with an air regulating valve, and the opening of the air regulating valve is controlled so that the preheated air matches the volatile content from the volatile collection bin (13); When the first kiln body (1) is in operation, the petroleum coke is heated to a preheating temperature in the preheating zone (11) of the first kiln body (1), generating a large amount of volatile matter. The volatile matter enters the first fire channel (12) under the action of negative pressure and is split in the first fire channel (12), with one part being used for combustion to heat the preheating zone (11) and the other part being collected in the volatile matter collecting bin (13); The preheated petroleum coke is firstly sent to the calcination zone (21) of the second kiln body (2), and after high-temperature calcination, high-temperature calcined petroleum coke is obtained. The high-temperature calcined petroleum coke is sent to the precooling zone (22) of the second kiln body (2) for preliminary cooling. The second fan blows cold air into the air duct (24). The cold air in the air duct (24) exchanges heat with the high-temperature calcined petroleum coke in the precooling zone (22), thereby obtaining petroleum coke after preliminary cooling and preheated air. The preheated air in the air duct (24) is sent to the second fire duct (23) connected to the air duct (24), and then mixed with volatiles from the volatiles collecting bin (13) and burned, so as to heat the calcination zone (21) to the calcination temperature. The cooling kiln (3) is used for the petroleum coke to enter after the initial temperature reduction for temperature reduction and cooling.

2. The multi-stage petroleum coke calcining equipment according to claim 1, characterized in that: The outlet of the first fire channel (12) is connected to the volatile matter collection bin (13) via an induced draft fan.

3. The multi-stage petroleum coke calcining equipment according to claim 1, characterized in that: The preheating zone (11) is also provided with a first fuel adding port (14), and the first fuel adding port (14) is connected to the first fire channel (12).

4. The multi-stage petroleum coke calcining equipment according to claim 1, characterized in that: The calcining zone (21) is also provided with a second fuel addition port (25), and the second fuel addition port (25) is connected to the second fire channel (23).

5. The multi-stage petroleum coke calcining equipment according to claim 1, characterized in that: The cooling kiln (3) is a drum-type cooler, which is provided with a direct cooling pipe inside for directly spraying cooling water on the pre-cooled material, and an indirect cooling pipe outside for cooling the drum wall.

6. The multi-stage petroleum coke calcining equipment according to claim 1, characterized in that: The discharge port of the first kiln body (1) is connected to the feed port of the second kiln body (2) via an electric slide pipe, and the discharge port of the second kiln body (2) is connected to the feed port of the cooling kiln (3) via an electric slide pipe.

7. The multi-stage petroleum coke calcining equipment according to claim 1, characterized in that: The first kiln body (1), the second kiln body (2) and the cooling kiln (3) are all arranged tilted, and are tilted 3-6° from horizontal.

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