Method for the production of needle coke feedstock
By combining centrifugation, stirring, and pressure filtration, along with inorganic flocculants and water dilution technology, the problems of high resource consumption and difficult waste treatment in the pretreatment of needle coke raw materials have been solved, achieving energy saving, increased production, and environmental protection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HENAN KAITAN NEW MATERIAL
- Filing Date
- 2023-11-27
- Publication Date
- 2026-05-12
AI Technical Summary
Existing pretreatment processes for needle coke feedstock suffer from high resource consumption, difficulty in waste disposal, and significant pollution risks, making it difficult to achieve efficient and environmentally friendly pretreatment results.
A multi-stage synergistic approach combining centrifugation, stirring, and pressure filtration, along with inorganic flocculants and water dilution technology, is employed to purify coal tar and recover impurities through the design of centrifuges, stirring tanks, and filter components.
It achieves energy conservation and increased production, reduces resource consumption and waste generation, improves pretreatment efficiency, and has good environmental and economic value, making it suitable for widespread application.
Smart Images
Figure CN117327505B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of chemical technology, and in particular to a pretreatment method for producing needle coke feedstock. Background Technology
[0002] Needle coke is a high-quality carbon raw material, mainly used in the production of high-power graphite electrodes for electric arc furnace steelmaking and high-energy neutron moderator materials for lithium-ion batteries. The needle coke production process includes three steps: raw material pretreatment, delayed coking, and calcination. Among these, raw material pretreatment has a significant impact on the quality of needle coke; controlling the content of quinoline insolubles and achieving a reasonable molecular weight distribution in the raw materials are key aspects of raw material pretreatment.
[0003] Pretreatment can effectively remove impurities such as QI and S from raw materials and improve their properties. Using multiple pretreatment methods in combination can effectively improve the performance of raw material preparation, laying a solid foundation for the subsequent preparation of high-performance needle coke. Summary of the Invention
[0004] The purpose of this invention is to provide a pretreatment method for needle coke raw materials, so as to achieve energy saving and increased production while ensuring the pretreatment effect.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A pretreatment method for producing needle coke feedstock includes the following steps:
[0007] S1. Centrifugation: The coal tar raw material is processed by a centrifuge to obtain an upper layer of centrifugal liquid and a lower layer of solid matter.
[0008] S2. Stirring process: Transfer the centrifuged liquid to an intermediate tank, add additives, stir, and let stand.
[0009] S3. Filtration and separation: Pressurized filtration yields purified coal tar.
[0010] S4. Recycling: The solid phase is sent to a mixing tank for recycling.
[0011] In some embodiments, in step S1, the coal tar raw material is fed into a centrifuge after being processed in the preceding steps.
[0012] The pretreatment process includes a settling tank process and a heating process, which are set up sequentially.
[0013] Specifically, the coal tar feedstock is allowed to settle in a settling tank to remove large insoluble particles; then, it is sent to a centrifuge through a heated pipe.
[0014] In some embodiments, in step S1, the temperature of the settling tank is 50~60°C, and the tank is left to stand for 10~15 hours.
[0015] In some embodiments, in step S1, multiple settling tanks are provided; each settling tank is independently connected to a centrifuge.
[0016] In some embodiments, it also includes:
[0017] In step S4, the sediment in the settling tank is sent to the mixing tank.
[0018] In some embodiments, in step S1, the temperature of the coal tar feedstock fed into the centrifuge is 80~100℃;
[0019] The centrifugation speed is 5000~6000 r / min, and the centrifugation time is 2~3 min.
[0020] In some embodiments, in step S2, the additive is an inorganic flocculant;
[0021] The amount of inorganic flocculant added is 2% to 5% of the centrifuged liquid.
[0022] In some embodiments, in step S2, the additive further includes water;
[0023] The amount of water added is 30% to 50% of the centrifuged liquid;
[0024] In step S3, the layered aqueous solution is discharged before filtration.
[0025] In some embodiments, in step S3, the filter screen is 200-300 mesh and the pressure is 1.5-1.8 MPa.
[0026] In some embodiments, the intermediate tank is provided with an inlet located at the top, an outlet and a slag discharge port located at the bottom, and an air inlet and a drain port located at the top.
[0027] The intermediate tank is equipped with a stirring element and a filter element;
[0028] The front side of the intermediate tank is provided with a vertically arranged transparent window;
[0029] One or more additive inlets are provided at the top of the intermediate tank;
[0030] The stirring component is a motor-driven stirring shaft, and the filter element is located at the bottom inside; the transparent window is made of high-temperature and high-pressure resistant high-strength glass.
[0031] The drain outlet is equipped with a vertically lifting suction pipe;
[0032] The drain outlet is a straight pipe structure vertically installed above the intermediate tank, and the suction pipe is a straight pipe with depth markings on the outside.
[0033] The filter element has a pointed cone structure, and the slag discharge port is located at the lower end of the outer edge of the pointed cone structure.
[0034] The slag discharge ports are arranged in a ring around the slag discharge ports and extend outward at an angle to form a guide port;
[0035] A stirring support rod and a spiral are provided on the outside of the stirring shaft;
[0036] The lower end of the agitator is provided with a cleaning component that mates with the upper surface of the filter element;
[0037] The cleaning component includes an extension rod arranged parallel to the upper surface of the filter element, and bristles arranged on the extension rod;
[0038] Multiple extension rods are arranged around the perimeter;
[0039] The intermediate tank is equipped with an internal cleaning mechanism.
[0040] The internal cleaning mechanism includes multiple high-pressure nozzles arranged around the filter element with their water outlets facing the upper surface of the filter element, and multiple annular tubes arranged in layers on the inner wall of the intermediate tank, with water holes opening on the annular tubes facing the inner wall.
[0041] The cross-section of the annular tube is a semi-elliptical structure, with water inlets opened above and below it respectively;
[0042] The annular pipe is also equipped with a water supply port that connects to the outside.
[0043] Compared with the prior art, the present invention provides a pretreatment method for producing needle coke raw materials, which has the following beneficial effects.
[0044] 1. This invention saves resources, avoids waste generation and pollution risks, and has good environmental value; the multi-process collaboration results in good pretreatment effect.
[0045] 2. This invention recovers all separated impurities, reducing consumption and costs while increasing output; it achieves increased production and reduced emissions, possessing excellent environmental and economic value and promising prospects for widespread application.
[0046] 3. In this invention, multiple inlet and outlet positions are rationally arranged on the intermediate tank for convenient use and maintenance; the transparent window combined with the drain outlet enables convenient, efficient, and precise discharge of stratified water without the need for complex structures; the filter element's shape provides a larger filtration area and higher filtration efficiency, reducing residue accumulation and facilitating cleaning and maintenance; the slag discharge port surrounds the flow guide for easy slag discharge, cleaning, and maintenance; the stirring rod combined with a spiral enhances internal stirring and circulation efficiency; the unique design of the internal cleaning mechanism ensures structural reliability and excellent cleaning effect.
[0047] Other advantages, objectives and features of the invention will be set forth in part in the description which follows; and in part will be apparent to those skilled in the art upon examination of the following description; or may be learned from practice of the invention. Attached Figure Description
[0048] Figure 1 This is a schematic diagram of the present invention.
[0049] Figure 2 This is a schematic diagram of the intermediate tank.
[0050] Figure 3 This is a schematic diagram of the lower structure of the intermediate tank.
[0051] Figure 4 This is a schematic cross-sectional view of the intermediate tank.
[0052] Figure 5 for Figure 4 A magnified structural diagram of point A in the middle.
[0053] Figure 6 This is a schematic diagram of the agitator.
[0054] Figure 7 This is a partial cross-sectional view of a single-layer annular pipe.
[0055] 1. Imported;
[0056] 2. Export;
[0057] 3. Slag discharge port;
[0058] 4. Air intake pressurization port;
[0059] 5. Drainage outlet;
[0060] 6. Agitator component; 61. Agitator shaft; 62. Agitator support rod; 63. Spiral;
[0061] 7. Filter components;
[0062] 8. Transparent viewport;
[0063] 9. Cleaning parts; 91. Extension rod;
[0064] 10. Internal cleaning mechanism; 101. High-pressure nozzle; 102. Ring pipe; 103. Water supply port;
[0065] 11. Additives addition port. Detailed Implementation
[0066] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.
[0067] Example 1.
[0068] Reference Figure 1 A pretreatment method for producing needle coke feedstock includes the following steps:
[0069] S1. Centrifugation: The coal tar raw material is processed by a centrifuge to obtain an upper layer of centrifugal liquid and a lower layer of solid matter.
[0070] S2. Stirring process: Transfer the centrifuged liquid to an intermediate tank, add additives, stir, and let stand.
[0071] S3. Filtration and separation: Pressurized filtration yields purified coal tar.
[0072] S4. Recovery: The solids from step S1 and the filter residue from step S3 are sent to a mixing tank for recovery.
[0073] In this process, the purification steps are almost entirely physical reactions, eliminating the need for repeated additions of complex chemical reagents. This not only saves resources but also avoids subsequent waste disposal and pollution risks, thus demonstrating significant environmental value.
[0074] Furthermore, the multi-step process in this technology works in concert, resulting in excellent pretreatment effects that fully meet the requirements. Moreover, all separated impurities are recycled, further reducing consumption and costs while increasing output.
[0075] Overall, this process achieves increased production and reduced emissions, consumes very few chemical products, has excellent environmental and economic value, and has good prospects for promotion.
[0076] It should also be noted that:
[0077] In step S4, the solid phase can be sent to a mixing tank, a solvent can be added, and the solid phase can be recovered by distillation. The selection of the solvent and the distillation process can be based on the existing technology for the treatment of coal tar pitch.
[0078] Similarly, it can be sold or reused directly without any further processing; then it can be processed when it is actually used.
[0079] Example 2.
[0080] In step S1, the coal tar raw material is fed into a centrifuge after previous processing.
[0081] The pretreatment process includes a settling tank process and a heating process, which are set up sequentially.
[0082] Specifically, the coal tar feedstock is allowed to settle in a settling tank to remove large insoluble particles; then, its temperature is raised through a heating pipe before it is sent to a centrifuge.
[0083] In step S1, the temperature of the settling tank is 50~60℃, and it is left to stand for 10~15 hours.
[0084] Preferably, the temperature of the settling tank is 60°C, and the settling time is 10 hours.
[0085] The settling tank can be heated by water bath, steam, or electric heating tubes, and attention should be paid to ensuring that the temperature is uniform and stable throughout.
[0086] It is understandable that:
[0087] Multiple settling tanks are provided, and each settling tank is independently connected to the centrifuge to ensure continuous production.
[0088] In some embodiments, it also includes:
[0089] In step S4, the sediment in the settling tank is sent to the mixing tank.
[0090] This will further enable the full utilization of raw materials and increase economic output.
[0091] In some embodiments:
[0092] In step S1, the temperature of the coal tar raw material fed into the centrifuge is 80~100℃; the centrifugation speed is 5000~6000r / min; and the centrifugation time is 2~3min.
[0093] Preferred:
[0094] The temperature of the coal tar raw material fed into the centrifuge was 90℃, the centrifugation speed was 5500r / min, and the centrifugation time was 2min.
[0095] In some embodiments, in step S2, the additive is an inorganic flocculant.
[0096] Adding inorganic flocculants can improve the coagulation and sedimentation of quinoline insolubles in coal tar.
[0097] The amount of inorganic flocculant added is 5% to 10% of the volume of the centrifuged liquid.
[0098] Preferably, the amount of inorganic flocculant added is 8% of the volume of the centrifuged liquid.
[0099] In some embodiments, in step S2, the additive also includes water.
[0100] The amount of water added is 30% to 50% of the volume of the centrifuged liquid;
[0101] It should be noted that water and coal tar are insoluble; water is added to dilute the coal tar to a certain extent under stirring; at the same time, it allows some impurities in the coal tar to dissolve into the water, further improving the purification effect.
[0102] Those skilled in the art know that conventional operations typically employ chemicals such as demulsifiers; however, this process optimizes the use of water for dilution.
[0103] Accordingly, in step S3, the layered aqueous solution is discharged before filtration.
[0104] In some embodiments, in step S3, the filter screen is 200-300 mesh and the pressure is 1.5-1.8 MPa.
[0105] Preferably, the filter screen is 250 mesh and the pressure is 1.7 MPa.
[0106] In some embodiments, step S3 further includes adding an inert protective gas.
[0107] Preferably, nitrogen is used as the inert protective gas.
[0108] Example 3.
[0109] In this embodiment:
[0110] In step S1, the temperature of the settling tank is 60℃, and it is left to stand for 14 hours; the coal tar raw material fed into the centrifuge is 100℃, the centrifugation speed is 5300r / min, and the centrifugation time is 2min.
[0111] In step S2, the amount of inorganic flocculant added is 7% of the volume of the centrifuged liquid, and the amount of water added is 30% of the volume of the centrifuged liquid;
[0112] In step S3, the filter screen is 250 mesh and the pressure is 1.5 MPa.
[0113] Example 4.
[0114] In this embodiment:
[0115] In step S1, the temperature of the settling tank is 55℃, and it is left to stand for 12 hours; the coal tar raw material fed into the centrifuge is 75℃, the centrifugation speed is 5000r / min, and the centrifugation time is 3min.
[0116] In step S2, the amount of inorganic flocculant added is 10% of the volume of the centrifuged liquid, and the amount of water added is 50% of the volume of the centrifuged liquid;
[0117] In step S3, the filter screen is 300 mesh and the pressure is 1.6 MPa.
[0118] Example 5.
[0119] In this embodiment:
[0120] In step S1, the temperature of the settling tank is 50℃, and it is left to stand for 11 hours; the coal tar raw material fed into the centrifuge is 80℃, the centrifugation speed is 6000 r / min, and the centrifugation time is 3 min.
[0121] In step S2, the amount of inorganic flocculant added is 6% of the volume of the centrifuged liquid, and the amount of water added is 40% of the volume of the centrifuged liquid;
[0122] In step S3, the filter screen is 280 mesh and the pressure is 1.7 MPa.
[0123] Example 6.
[0124] In this embodiment, an intermediate tank configuration is provided.
[0125] Reference Figure 2-7 The intermediate tank is equipped with an inlet 1 located at the top, an outlet 2 located at the bottom, a slag discharge port 3 located at the bottom, an air inlet pressurization port 4 located at the top, and a drain port 5 located at the top.
[0126] The intermediate tank is equipped with a stirring element 6 and a filter element 7.
[0127] A vertically arranged transparent viewing window 8 is provided on the front side of the intermediate tank.
[0128] Preferably, a depth scale is provided on the transparent window 8.
[0129] In addition, one or more additive inlets 11 are provided above the intermediate tank.
[0130] It is understandable that the intermediate tank is a sealable cylindrical tank; the sealing structure and the configuration of various inlets and outlets can be selected by those skilled in the art according to their functions, and a reasonable layout can be made; preferably, a manhole is provided at the top of the intermediate tank and sealed with a corresponding flange; each inlet and outlet adopts the form of a straight pipe with a flange.
[0131] The stirring component 6 is a motor-driven stirring shaft 61. The filter component 7 is located at the bottom inside and can be a standard industry-standard structure such as a filter plate or filter screen. The transparent viewing window 8 is made of high-temperature and high-pressure resistant high-strength glass for observing the internal conditions.
[0132] In some embodiments, the drain outlet 5 is equipped with a vertically movable suction pipe; depending on the different oil-water separation, the position of the bottom end of the suction pipe is adjusted to drain the water.
[0133] Specifically, the drain outlet 5 is a straight pipe structure vertically installed above the intermediate tank, and the suction pipe is a straight pipe with depth markings on the outside.
[0134] Correspondingly, the end of the drain outlet 5 is conventionally sealed with a sealing flange; after settling, the drain outlet 5 is opened and the suction pipe is vertically inserted into the drain outlet 5; the insertion depth is controlled according to the depth scale on the transparent window 8 and the depth scale on the suction pipe; then, the external pipeline discharges the stratified water.
[0135] In some embodiments, the filter element 7 has a pointed cone structure, and the slag discharge port 3 is located at the lower end of the outer edge of the pointed cone structure.
[0136] Therefore, its specially designed structure provides a larger filtration area and higher filtration efficiency; at the same time, it reduces the accumulation and residue of residue, and is easy to clean and maintain.
[0137] Understandably, the slag discharge port 3 is equipped with corresponding control valves, gates and other closed structures, and is in a blocked state under normal circumstances.
[0138] In some embodiments, multiple slag discharge ports 3 are arranged around the slag discharge port 3 and extend outward at an angle to form a guide port; this facilitates slag discharge and cleaning, maintenance and other operations.
[0139] In some embodiments, a stirring support rod 62 and a spiral 63 are provided on the outer side of the stirring shaft 61.
[0140] Preferably, in the working state, the spiral 63 forms a downward swirling flow, which enhances the internal stirring and circulation efficiency.
[0141] In some embodiments, the lower end of the agitator 6 is provided with a cleaning element 9 that mates with the upper surface of the filter element 7.
[0142] Specifically, the cleaning component 9 includes an extension rod 91 arranged parallel to the upper surface of the filter component 7, and bristles arranged on the extension rod 91.
[0143] Preferably, multiple extension rods 91 are arranged around the perimeter.
[0144] It should be noted that there should be at least two extension rods 91 to facilitate balance control and ensure effective cleaning.
[0145] In some embodiments, an internal cleaning mechanism 10 is provided inside the intermediate tank.
[0146] The internal cleaning mechanism 10 includes multiple high-pressure nozzles 101 arranged around the filter element 7 with their water outlets facing the upper surface of the filter element 7, and multiple annular pipes 102 arranged in layers on the inner wall of the intermediate tank. The annular pipes 102 have water holes facing the inner wall.
[0147] Multiple high-pressure nozzles 101 extend from the outside to the inside, ensuring a seal; the high-pressure nozzles 101 are connected in series on the outside via a ring-shaped water pipe for water supply.
[0148] In some embodiments, the cross-section of the annular tube 102 is a semi-elliptical structure; the water inlet holes are respectively opened above and below it.
[0149] Therefore, it forms a flat protrusion that fits into the inner wall, making it less likely to stick or leave residue. Compared to a circular tube, this structure has a stronger load-bearing capacity, is more rounded, reliable, and easy to clean.
[0150] It is understood that the annular pipe 102 is also provided with a water supply port 103 connected to the outside.
[0151] As shown in the attached figure, the interior is provided with three layers of annular pipes 102, and correspondingly, three water supply ports 103 are provided on the outside; accordingly, the annular water pipe connected to the high-pressure nozzle 101 is located on the lower outer side, and is also provided with a water supply interface.
[0152] In some embodiments, the intermediate tank is provided with multiple support legs at its bottom to raise the whole structure; at the same time, the lower part of the intermediate tank is a hemispherical structure, and the outlet 2 is located at its lowest end.
[0153] In this embodiment, multiple inlet and outlet positions are rationally arranged for convenient use and maintenance; the transparent window 8, combined with the drain outlet 5, enables convenient, efficient, and precise discharge of stratified water without the need for complex structures; the filter element 7 has a larger filtration area, higher filtration efficiency, reduced residue accumulation, and is easy to clean and maintain; the slag discharge port 3 forms a guide port around the filter element for easy slag discharge, cleaning, and maintenance; the stirring support rod 62, combined with the spiral 63, enhances the internal stirring and circulation efficiency; the unique design of the internal cleaning mechanism 10 ensures reliable structure and good cleaning effect.
[0154] This invention saves resources, avoids waste and pollution risks, and has good environmental value; multiple processes work together to achieve good pretreatment results; all separated impurities are recovered, reducing consumption and costs while increasing output; it achieves increased production and reduced emissions, and has excellent environmental and economic value, with good prospects for promotion.
[0155] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
[0156] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0157] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.
Claims
1. A pretreatment method for producing needle coke feedstock, characterized in that, Includes the following steps: S1. Centrifugation: The coal tar raw material is processed by a centrifuge to obtain an upper layer of centrifugal liquid and a lower layer of solid matter. S2. Stirring process: Transfer the centrifuged liquid to an intermediate tank, add additives, stir, and let stand. S3. Filtration and separation: Pressurized filtration yields purified coal tar. S4. Recycling: The solid material is sent to a mixing tank for recycling. In step S1, the coal tar raw material is fed into a centrifuge after previous processing; The pretreatment process includes a settling tank process and a heating process set up in sequence; the coal tar raw material is allowed to settle in the settling tank to remove large particles of insoluble matter; the temperature of the settling tank is 50~60℃, and it is left to stand for 10~15 hours; afterwards, it is sent to the centrifuge through the heating pipe; there are multiple settling tanks; each settling tank is independently connected to the centrifuge to ensure continuous production. In step S2, the auxiliary agent is an inorganic flocculant and water; wherein the amount of water added is 30% to 50% of the centrifuged liquid. In step S3, the layered aqueous solution is discharged before filtration; Adding water dilutes the coal tar; some impurities in the coal tar dissolve into the water, further improving the purification effect. In step S4, the sediment in the settling tank is sent to the mixing tank to further make full use of the raw materials and increase economic output. The intermediate tank is provided with a drain outlet (5), and a vertically arranged transparent window (8) is provided on the front side of the intermediate tank; the intermediate tank is provided with a stirring component (6), a filter component (7), and an internal cleaning mechanism (10). The drain outlet (5) is equipped with a vertically lifting suction tube; adjust the bottom position of the suction tube according to different oil-water separation to drain the water; when in use, control the insertion depth according to the depth scale on the transparent window (8) and the depth scale on the suction tube. The filter element (7) is located at the bottom of the interior and has a pointed cone structure; the slag discharge port (3) is located at the lower end of the outer edge of the pointed cone structure; with its specially designed structure, it has a larger filtration area and higher filtration efficiency; at the same time, it reduces the accumulation and residue of slag and is extremely easy to clean and maintain. The internal cleaning mechanism (10) includes multiple high-pressure nozzles (101) arranged around the filter element (7) with the water outlet facing the upper surface of the filter element (7), and multiple annular tubes (102) arranged in layers on the inner wall of the intermediate tank. The annular tubes (102) are provided with water holes facing the inner wall. The cross-section of the annular tubes (102) is a semi-elliptical structure, which forms a flat protrusion with the inner wall, making it less likely to stick or leave residue. Compared with circular tubes, this structure has stronger load-bearing capacity, is more rounded, reliable, and easy to clean.
2. The pretreatment method for producing needle coke raw materials according to claim 1, characterized in that, In step S1, the temperature of the coal tar feedstock fed into the centrifuge is 80~100℃; The centrifugation speed is 5000~6000 r / min, and the centrifugation time is 2~3 min.
3. The pretreatment method for producing needle coke raw materials according to claim 1, characterized in that, In step S3, the filter screen is 200~300 mesh, and the pressure is 1.5~1.8 MPa.
4. The pretreatment method for producing needle coke raw materials according to claim 1, characterized in that, Step S3 also includes adding an inert protective gas.