Graphite purification system
By combining multiple purification and recovery modules, the problem of large amounts of acid and neutralizing agents in existing graphite purification systems has been solved, achieving effective resource utilization and cost reduction.
Patent Information
- Application Number
- CN202520022101.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-02
- Publication Date
- 2026-01-13
- Estimated Expiration
- 2035-01-02
AI Technical Summary
In existing graphite purification systems, the large amounts of acid and neutralizing agents used result in high wastewater treatment costs.
The system employs a combination of multiple purification and recovery modules, including a first acid purification module, an alkali purification module, a second acid purification module, a first recovery module, and a second recovery module. By recovering and reusing the acid solution, the amount of neutralizing agent required is reduced.
This reduced the amount of acid and neutralizing agents used, lowered wastewater treatment costs, and achieved efficient resource utilization.
Smart Images
Figure CN223792910U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of graphite purification waste acid treatment technology, specifically to a graphite purification system. Background Technology
[0002] The industrial production of high-purity graphite primarily relies on chemical purification. This process can generate large amounts of acidic wastewater, requiring significant amounts of quicklime for neutralization before discharge to meet emission standards. Current graphite purification systems typically employ two acid leaching processes to enhance purity, but these methods have drawbacks. For example, the large quantities of acid and neutralizing agents used in both processes lead to high wastewater treatment costs. Utility Model Content
[0003] To address the shortcomings of existing technologies, it is necessary to provide a graphite purification system that can reduce costs.
[0004] This application provides a graphite purification system for purifying graphite materials, including a first acid purification module, an alkali purification module, a second acid purification module, a first recovery module, and a second recovery module. The first acid purification module performs primary purification of the graphite. The alkali purification module is connected to the first acid purification module and performs secondary purification of the primary purified graphite. The second acid purification module is connected to the alkali purification module and performs tertiary purification of the secondary purified graphite. The first recovery module is connected to the first acid purification module, the alkali purification module, and the second acid purification module, and is used to recover wastewater generated in these modules. The second recovery module is connected to both the first acid purification module and the second acid purification module and is used to collect acid from the second acid purification module and transport the acid back to both modules.
[0005] This application establishes a first acid purification module, an alkali purification module, a second acid purification module, a first recovery module, and a second recovery module. The second acid purification module addresses this by using a different approach. Since the acid solution from the first acid purification module contains many impurities after leaching and is unusable, it is neutralized with the alkali wastewater collected in the alkali purification module. This reduces the use of neutralizing agents and is environmentally friendly. The second acid purification module contains fewer impurities, allowing for the recovery of the acid solution from this module. The recovered acid solution can then be reused in the acid purification process of new materials. This purification system not only recycles acid and reduces acid usage but also reduces the amount of neutralizing agent needed for subsequent wastewater neutralization, thus lowering costs.
[0006] In some embodiments of this application, the second recovery module includes an acid collection unit and a dosing unit connected in sequence. The acid collection unit is connected to the second acid purification module and is used to collect the acid in the second acid purification module. The dosing unit is used to detect the flow rate of the acid in the acid collection unit and to deliver the acid to the first acid purification module and the second acid purification module.
[0007] In some embodiments of this application, the second recovery module further includes an acid mixing unit, which is connected to the first acid purification module and the second acid purification module respectively and is used to transport acid to the first acid purification module and the second acid purification module.
[0008] In some embodiments of this application, the second acid purification module includes a second reaction vessel, a third filter press, and / or a third centrifuge connected in sequence. The second reaction vessel is connected to the alkali purification module and is used to receive graphite after secondary purification. The third filter press is connected to the second reaction vessel, the first recovery module, and the acid collection unit. The third filter press is used to filter the graphite after secondary acid purification and to transport the filtered acid to the acid collection unit, and to transport the filtered wastewater to the first recovery module. The third centrifuge is used to centrifuge the graphite after tertiary purification or after filter pressing, to transport the centrifuged acid to the acid collection unit, and to transport the centrifuged wastewater to the first recovery module.
[0009] In some embodiments of this application, screens are provided between the third centrifuge and the acid collection unit, and between the third filter press and the acid collection unit.
[0010] In some embodiments of this application, the acid collection unit includes a first collection subunit and a second collection subunit. The first collection subunit is connected to a third centrifuge, and the second collection subunit is connected to a third filter press. The dosing unit includes a first metering subunit and a second metering subunit. The first metering subunit is disposed between the first collection subunit and the acid preparation unit and is used to detect the amount of acid in the first collection subunit. The second metering subunit is disposed between the second collection subunit and the acid preparation unit and is used to detect the amount of acid in the second collection subunit.
[0011] In some embodiments of this application, the mesh size of the sieve is greater than or equal to 1000 mesh.
[0012] In some embodiments of this application, the first acid purification module includes a first reaction vessel, a first filter press, a first centrifuge, and a dryer connected in sequence. The first reaction vessel is used to purify graphite once and receive acid from the second recovery module. The first filter press is used to filter the graphite in the first reaction vessel and transport the filtered wastewater to the first recovery module. The first centrifuge is used to centrifuge the graphite in the first filter press and transport the centrifuged wastewater to the first recovery module. The dryer is connected to the alkali purification module and is used to dry the graphite in the first centrifuge and then transport it to the alkali purification module.
[0013] In some embodiments of this application, the alkali purification module includes a mixer, a rotary kiln, a second filter press, and a second centrifuge connected in sequence. The mixer is connected to the first acid purification module and is used to receive graphite after primary purification. The rotary kiln is used to dry the graphite. The second filter press is connected to both the rotary kiln and the first recovery module. The second filter press is used to filter the dried graphite and transport the filtered wastewater to the first recovery module. The second centrifuge is connected to both the second filter press and the first recovery module. The second centrifuge is used to centrifuge the filtered graphite and transport the centrifuged wastewater to the first recovery module.
[0014] In some embodiments of this application, the first recycling module includes a primary wastewater recycling unit, a secondary wastewater recycling unit, a tertiary wastewater recycling unit, and a neutralization treatment unit. The primary wastewater recycling unit is connected to the first acid purification module and the neutralization treatment unit, respectively. The secondary wastewater recycling unit is connected to the alkali purification module and the neutralization treatment unit, respectively. The tertiary wastewater recycling unit is connected to the second acid purification module and the neutralization treatment unit, respectively. The neutralization treatment unit is used to neutralize the wastewater in the primary wastewater recycling unit, the secondary wastewater recycling unit, and the tertiary wastewater recycling unit. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of a graphite purification system according to one embodiment of this application.
[0016] Explanation of key component symbols:
[0017] First acid purification module 100; alkali purification module 200; second acid purification module 300; first recovery module 400; second recovery module 500; first reaction vessel 101; first filter press 102; first centrifuge 103; dryer 104; mixer 201; rotary kiln 202; second filter press 203; second centrifuge 204; second reaction vessel 301; third filter press 302; third centrifuge 303; primary wastewater recovery unit 401; secondary wastewater recovery unit 402; tertiary wastewater recovery unit 403; neutralization treatment unit 404; acid collection unit 10; dosage unit 520; acid preparation unit 530; first collection subunit 511; second collection subunit 512; first metering subunit 521; second metering subunit 522.
[0018] The following detailed description, in conjunction with the accompanying drawings, will further illustrate this application. Detailed Implementation
[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.
[0020] It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or may also have a component that is centrally located. When a component is considered to be "located" on another component, it can be directly located on the other component or may also have a component that is centrally located.
[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0022] Please see Figure 1This application provides a graphite purification system for purifying graphite materials, including a first acid purification module 100, an alkali purification module 200, a second acid purification module 300, a first recovery module 400, and a second recovery module 500. The first acid purification module 100 performs primary purification of the graphite. The alkali purification module 200 is connected to the first acid purification module 100 and performs secondary purification of the primary purified graphite. The second acid purification module 300 is connected to the alkali purification module 200 and performs tertiary purification of the secondary purified graphite. The first recovery module 400 is connected to the first acid purification module 100, the alkali purification module 200, and the second acid purification module 300, and performs wastewater recovery from these modules. The second recovery module 500 is connected to the first acid purification module 100 and the second acid purification module 300 respectively, and is used to collect the acid solution in the second acid purification module 300 and transport the acid solution to the first acid purification module 100 and the second acid purification module 300. The modules can be connected to each other through pipelines.
[0023] This application establishes a first acid purification module 100, an alkali purification module 200, a second acid purification module 300, a first recovery module 400, and a second recovery module 500. The second acid purification module 300 is used because the graphite material itself has low impurity content after primary and secondary purification, and most of the impurities have been removed after the secondary purification. After three purification processes, the acid solution formed after acid leaching has low impurity content. Therefore, the acid solution in the second acid purification module 300 can be recovered and used in the primary purification acid leaching process. Alternatively, the recovered acid solution can be mixed with new acid solution and reused in the second acid purification module 300. This not only allows for the recycling of acid solution and reduces acid usage but also reduces the amount of neutralizing agent needed for subsequent wastewater neutralization treatment, thereby reducing costs.
[0024] In one embodiment of this application, the second recovery module 500 includes an acid collection unit 510 and a dosing unit 520 connected in sequence. The acid collection unit 510 is connected to the second acid purification module 300 and is used to collect the acid in the second acid purification module 300. The dosing unit 520 is used to detect the flow rate of the acid in the acid collection unit 510 and to transport the acid to the first acid purification module 100 and the second acid purification module 300.
[0025] In one embodiment of this application, the second recovery module 500 further includes an acid mixing unit 530, which is connected to the first acid purification module 100 and the second acid purification module 300 respectively and is used to transport acid to the first acid purification module 100 and the second acid purification module 300.
[0026] In one embodiment of this application, the second acid purification module 300 includes a second reaction vessel 301, a third filter press 302, and / or a third centrifuge 303 connected in sequence. The second reaction vessel 301 is connected to the second recovery module 500 and the alkali purification module 200 and is used to receive graphite after secondary purification and to add acid recovered by the second recovery module 500 to the new acid for acid leaching treatment. The third filter press 302 is connected to the second reaction vessel 301, the first recovery module 400, and the acid collection unit 510. The third filter press 302 is used to filter the graphite after secondary purification and to transport the filtered acid to the acid collection unit 510, and to transport the filtered wastewater to the first recovery module 400. The third centrifuge 303 is used to centrifuge the graphite after secondary acid purification or after filter pressing and to transport the centrifuged acid to the acid collection unit 510, and to transport the centrifuged wastewater to the first recovery module 400. The material from the second acid reaction is subjected to pressure filtration and centrifugation. The pressure filtration and centrifugation processes are each equipped with acid collection pipes connected to the second recovery module 500 to collect the acid. The collected acid can be reused directly or mixed with some new acid. This process eliminates the need for ion exchange membranes to treat the old acid, effectively saving on the maintenance and replacement costs of membranes in the acid recovery process. The mixed acid is also used for subsequent acid leaching, which effectively reduces the amount of new acid used.
[0027] In one embodiment of this application, screens are provided between the third centrifuge 303 and the acid collection unit 510, and between the third filter press 302 and the acid collection unit 510. By providing screens, graphite can be screened out, and old acid solution enters the acid collection unit 510 through the screens. New acid solution can be added to the acid preparation unit 530 so that the acid solution can be used for acid leaching in the first acid purification module 100, reducing costs and waste.
[0028] In one embodiment of this application, the acid collection unit 510 includes a first collection subunit 511 and a second collection subunit 512. The first collection subunit 511 is connected to a third centrifuge 303, and the second collection subunit 512 is connected to a third filter press 302. The dosing unit 520 includes a first metering subunit 521 and a second metering subunit 522. The first metering subunit 521 is disposed between the first collection subunit 511 and the acid mixing unit 530 and is used to detect the amount of acid in the first collection subunit 511. The second metering subunit 522 is disposed between the second collection subunit 512 and the acid mixing unit 530 and is used to detect the amount of acid in the second collection subunit 512. By setting the dosing unit, the amount of old acid entering can be calculated, thereby adjusting the amount of newly added acid in the acid mixing unit 530 to achieve automatic mixing. On the other hand, by providing a dosing unit, a concentration detection device can also be installed in the acid mixing unit 530 to monitor the acid concentration in the acid mixing tank in real time, enabling precise mixing and reuse of waste acid and fresh acid. Preferably, the first metering subunit 521 and the second metering subunit 522 are dosimeters. Preferably, the first collection subunit 511 and the second collection subunit 512 are acid collection tanks.
[0029] In one embodiment of this application, an acid with a mass fraction of 10-20% is formed in the first collection subunit 511, and the acid recovered by the first collection subunit 511 is one or any two of hydrochloric acid, nitric acid, and sulfuric acid. An acid with a mass fraction of 60-80% is formed in the second collection subunit 512, and the acid recovered by the second collection subunit 512 is one or any two of hydrochloric acid, nitric acid, and sulfuric acid.
[0030] In one embodiment of this application, the mesh size of the sieve is greater than or equal to 1000 mesh.
[0031] In one embodiment of this application, the first acid purification module 100 includes a first reaction vessel 101, a first filter press 102, a first centrifuge 103, and a dryer 104 connected in sequence. The first reaction vessel 101 is used to purify graphite once and receive acid from the second recovery module 500. The first filter press 102 is used to filter the graphite in the first reaction vessel 101 and transport the filtered wastewater to the first recovery module 400. The first centrifuge 103 is used to centrifuge the graphite in the first filter press 102 and transport the centrifuged wastewater to the first recovery module 400. The dryer 104 is connected to the alkali purification module 200 and is used to dry the graphite in the first centrifuge 103 and then transport it to the alkali purification module 200.
[0032] In one embodiment of this application, the alkali purification module 200 includes a mixer 201, a rotary kiln 202, a second filter press 203, and a second centrifuge 204 connected in sequence. The mixer 201 is connected to the first acid purification module 100 and is used to receive graphite after primary purification. The rotary kiln 202 is used to dry the graphite. The second filter press 203 is connected to both the rotary kiln 202 and the first recovery module 400. The second filter press 203 is used to filter the dried graphite and transport the filtered wastewater to the first recovery module 400. The second centrifuge 204 is connected to both the second filter press 203 and the first recovery module 400. The second centrifuge 204 is used to centrifuge the filtered graphite and transport the centrifuged wastewater to the first recovery module 400. More preferably, the mixer 201 is a VC mixer.
[0033] In one embodiment of this application, the first recycling module 400 includes a primary wastewater recycling unit 401, a secondary wastewater recycling unit 402, a tertiary wastewater recycling unit 403, and a neutralization treatment unit 404. The primary wastewater recycling unit 401 is connected to the first acid purification module 100 and the neutralization treatment unit 404, respectively. The secondary wastewater recycling unit 402 is connected to the alkali purification module 200 and the neutralization treatment unit 404, respectively. The tertiary wastewater recycling unit 403 is connected to the second acid purification module 300 and the neutralization treatment unit 404, respectively. The neutralization treatment unit 404 is used to neutralize the wastewater in the primary wastewater recycling unit 401, the secondary wastewater recycling unit 402, and the tertiary wastewater recycling unit 403.
[0034] The graphite purification system described above will be further illustrated below through specific embodiments.
[0035] Example 1
[0036] 300 kg of graphite was purified using a graphite purification system. The mass ratio of graphite:hydrochloric acid:water was 1:0.325:1, and the mass fraction of hydrochloric acid was 36%. After mixing, the mixture was fed into the first reactor 101 for reaction. The mixture was then centrifuged using the first filter press 102 and the first centrifuge 103 to obtain centrifuged material. This material was then sent to the dryer 104 for drying via a ton bag. The acidic wastewater generated after the filter press and centrifugation entered the primary wastewater recovery unit 401. The mass ratio of the dried material to alkali was 1:0.25, and the mixture was fed into the VC mixer 201 for mixing. After mixing, the mixture was fed into the rotary kiln 202 for alkali roasting. After alkali roasting, the material was first filtered using the second filter press 203, and then centrifuged using the second centrifuge 204 to obtain centrifuged material. The alkaline wastewater generated after the filter press and centrifugation entered the secondary wastewater recovery unit 402. The centrifuged material was then mixed with acid in batches and fed into the second reactor 301, with each batch containing 50 kilograms of the final product. The process involves a graphite:hydrochloric acid:pure water mass ratio of 1:0.6:4.4, with hydrochloric acid having a mass fraction of 36%. After the reaction is complete, the solution is centrifuged in a third centrifuge 303 without using a third filter press 302. High-purity graphite is obtained after centrifugation. The waste acid solution generated by the third centrifuge 303 enters the first collection subunit 511 through a pipeline connection, collecting a total of 1320 kg of acid solution with a concentration of 13%, of which 171.6 kg is hydrochloric acid. The pipeline of the second collection subunit 512 is in a closed state. All the acid solution from the first collection subunit 511 enters the acid mixing unit 530 and is mixed with externally added new acid, which is a 36% hydrochloric acid solution. 192 kg of 36% hydrochloric acid solution is added to the acid mixing tank through the external acid, mixing to form a 25% hydrochloric acid solution for use in the first acid purification module 100. By reusing the waste acid, 44.83% of the new acid usage can be effectively saved. The acidic wastewater generated after centrifugation by the third centrifuge 303 enters the tertiary wastewater recovery unit 403. The wastewater in the primary wastewater recovery unit 401, the secondary wastewater recovery unit 402, and the tertiary wastewater recovery unit 403 is neutralized and further treated.
[0037] Example 2
[0038] 250 kg of graphite was purified using a graphite purification system. The mass ratio of graphite:hydrochloric acid:water was 1:0.5:1, and the mass fraction of hydrochloric acid was 36%. After mixing, the mixture was fed into the first reactor 101 for reaction. The mixture was then centrifuged using the first filter press 102 and the first centrifuge 103 to obtain centrifuged material. This material was then sent to the dryer 104 for drying via a ton bag. The acidic wastewater generated after the filter press and centrifugation entered the primary wastewater recovery unit 401. The dried material was mixed with alkali at a mass ratio of 1:0.35 and fed into the VC mixer 201 for further mixing. After mixing, the material was fed into the rotary kiln 202 for alkali roasting. After alkali roasting, the material was first filtered using the second filter press 203 and then centrifuged using the second centrifuge 204 to obtain centrifuged material. The alkaline wastewater generated after the filter press and centrifugation entered the secondary wastewater recovery unit 402. The centrifuged material was then mixed with acid in batches and fed into the second reactor 301, with each batch being 50 kg. The mass ratio of graphite:hydrochloric acid:nitric acid:pure water in this process was [missing information]. The ratio is 1:0.45:0.15:2.4, with hydrochloric acid having a mass fraction of 36% and nitric acid having a mass fraction of 68%. After the reaction is complete, the solution is filtered by the third filter press 302, without using the third centrifuge 303. High-purity graphite is obtained after filtration. The waste acid produced by the third filter press 302 enters the second acid collection subunit 512 through a pipeline connection, collecting a total of 720 kg of acid solution with a concentration of 20%. Among them, 144 kg is a mixed acid solution of hydrochloric acid and nitric acid. The pipeline of the collection tank 3 is in a closed state. All the acid solution in the second acid collection subunit 512 enters the acid mixing unit 530 and is mixed with the externally added new acid. The externally added acid solution is a mixed acid solution of hydrochloric acid:nitric acid = 3:1, with a hydrochloric acid mass fraction of 36% and a nitric acid mass fraction of 68%. By adding 139.7 kg of the mixed acid solution to the acid mixing tank, a mixed acid solution with a concentration of 33% is formed and used in the first acid purification module 100. Through waste acid recycling, 50.76% of the new acid usage can be effectively saved. The acidic wastewater generated by the third filter press 302 enters the tertiary wastewater recovery unit 403. The wastewater in the primary wastewater recovery unit 401, the secondary wastewater recovery unit 402, and the tertiary wastewater recovery unit 403 is neutralized and further treated.
[0039] Example 3
[0040] 300 kg of graphite was purified using a graphite purification system. The mass ratio of graphite:hydrochloric acid:water was 1:0.33:1, and the mass fraction of hydrochloric acid was 36%. After mixing, the mixture was fed into the first reactor 101 for reaction. The mixture was then centrifuged using the first filter press 102 and the first centrifuge 103 to obtain centrifuged material. This material was then sent to the dryer 104 for drying via a ton bag. The acidic wastewater generated after the filter press and centrifugation entered the primary wastewater recovery unit 401. The mass ratio of the dried material to alkali was 1:0.25, and the mixture was fed into the VC mixer 201 for mixing. After mixing, the mixture was fed into the rotary kiln 202 for alkali roasting. After alkali roasting, the material was first filtered using the second filter press 203, and then centrifuged using the second centrifuge 204 to obtain centrifuged material. The alkaline wastewater generated after the filter press and centrifugation entered the secondary wastewater recovery unit 402. The centrifuged material was then mixed with acid in batches and fed into the second reactor 301. The first batch consists of 50 kg of graphite. The mass ratio of graphite, hydrochloric acid, and pure water in this process is 1:0.7:4, with the hydrochloric acid having a mass fraction of 36%. After the reaction, the solution is centrifuged in a third centrifuge 303 (without using a third filter press 302). High-purity graphite is obtained after centrifugation. The waste acid produced by the third centrifuge 303 enters the first collection subunit 511 via a pipeline, collecting a total of 1120 kg of acid solution with a concentration of 15%, of which 168 kg is hydrochloric acid. The pipeline in the second collection subunit 512 is closed. All the acid solution from the first collection subunit 511 enters the acid mixing unit 530 and is mixed with externally added new acid, a 36% hydrochloric acid solution. 240 kg of 36% hydrochloric acid is added to the acid mixing tank to create a 30% hydrochloric acid solution, which is then used in the first acid purification module 100. Through waste acid reuse, 41.18% of new acid usage can be effectively saved. The acidic wastewater produced after centrifugation in the third centrifuge 303 enters the tertiary wastewater recovery unit 403. The wastewater in the primary wastewater recovery unit 401, the secondary wastewater recovery unit 402 and the tertiary wastewater recovery unit 403 is neutralized and subsequently treated.
[0041] Example 4
[0042] 300 kg of graphite was purified using a graphite purification system. The mass ratio of graphite to hydrochloric acid to water was 1:0.5:1, and the mass fraction of hydrochloric acid was 36%. After mixing, the mixture was fed into the first reaction vessel 101 for reaction. The centrifuged material obtained by the first filter press 102 and the first centrifuge 103 was then sent to the dryer 104 for drying via a ton bag. The acidic wastewater generated after the filter press and centrifugation entered the primary wastewater recovery unit 401. The mass ratio of the dried material to alkali was 1:0.25, and the mixture was then fed into the VC mixer 201 for mixing. The material, after being processed, enters rotary kiln 202 for alkali roasting. After roasting, the material is first filtered using a second filter press 203, and then centrifuged using a second centrifuge 204. The resulting alkaline wastewater from the filtration and centrifugation processes enters a secondary wastewater recovery unit 402. The centrifuged material is then mixed with acid in batches and fed into a second reaction vessel 301, with each batch weighing 50 kg. The mass ratio of graphite to hydrochloric acid to pure water in this process is 1:0.8:2.4, and the mass fraction of hydrochloric acid is 36%. After the reaction is complete, the material is centrifuged again in a third centrifuge 303. Without using the third filter press 302, high-purity graphite is obtained after centrifugation. The waste acid liquid generated by the third centrifuge 303 enters the first collection subunit 511 through a pipeline connection, collecting a total of 768 kg of acid liquid with a concentration of 25%, of which 192 kg is hydrochloric acid. The pipeline of the second collection subunit 512 is in a closed state. Part of the acid liquid from the first collection subunit 511 enters the acid mixing unit 530 to be mixed with externally added new acid. Among them, 500 kg of acid liquid from the first collection subunit 511 enters the acid mixing unit 530 to be mixed with externally added new acid. A 36% hydrochloric acid solution is added. 100 kg of 36% hydrochloric acid is added to the acid mixing tank to form a 33% hydrochloric acid solution, which is used in the first acid purification module 100 for a total acid leaching of 400 kg. The remaining 268 kg of acid from the first collection subunit 511 enters the acid mixing unit 530 and mixes with newly added acid. 148 kg of 36% hydrochloric acid is added to the acid mixing tank for use in the second acid purification module 300, effectively saving 38.3% of the new acid used. Acidic wastewater generated after centrifugation in the third centrifuge 303 enters the tertiary wastewater recovery unit 403. The wastewater from the primary wastewater recovery unit 401, secondary wastewater recovery unit 402, and tertiary wastewater recovery unit 403 undergoes neutralization and subsequent treatment.
[0043] Data measurements were performed on acid preparation unit 530 in Examples 1-4, and the resulting data are recorded in Table 1.
[0044]
[0045] As can be seen from Table 1, the graphite purification system provided in Examples 1-4 can effectively recycle and reuse the waste acid liquid during the purification process, reduce the amount of acid used in the purification process, and the reuse process does not require complicated treatment. It can be directly mixed with new acid for use, which can effectively save the maintenance cost and processing fee of the treatment equipment. It can also achieve automatic proportioning and is simple and convenient to operate.
[0046] The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this application without departing from the spirit and substance of the technical solutions of this application.
Claims
1. A graphite purification system for purifying graphite, characterized in that, The graphite purification system includes: The first acid purification module is used for the primary purification of graphite; An alkali purification module is connected to the first acid purification module and is used to perform secondary purification on the graphite after primary purification. The second acid purification module is connected to the alkali purification module and is used to perform a third purification on the graphite after the second purification. A first recovery module is connected to the first acid purification module, the alkali purification module, and the second acid purification module, and is used to recover wastewater generated in the first acid purification module, the alkali purification module, and the second acid purification module; and The second recovery module is connected to the first acid purification module and the second acid purification module, and is used to collect the acid solution in the second acid purification module and transport the acid solution to the first acid purification module and the second acid purification module.
2. The graphite purification system according to claim 1, characterized in that, The second recovery module includes an acid collection unit and a dosing unit connected in sequence. The acid collection unit is connected to the second acid purification module and is used to collect the acid in the second acid purification module. The dosing unit is used to detect the flow rate of the acid in the acid collection unit and to deliver the acid to the first acid purification module and the second acid purification module.
3. The graphite purification system according to claim 2, characterized in that, The second recovery module further includes an acid mixing unit, which is connected to the first acid purification module and the second acid purification module respectively and is used to transport the acid solution to the first acid purification module and the second acid purification module.
4. The graphite purification system according to claim 3, characterized in that, The second acid purification module includes a second reaction vessel, a third filter press, and / or a third centrifuge connected in sequence. The second reaction vessel is connected to the alkali purification module and is used to receive graphite after secondary purification. The third filter press is connected to the second reaction vessel, the first recovery module, and the acid collection unit. The third filter press is used to filter the graphite after tertiary purification and transport the filtered acid to the acid collection unit, and transport the filtered wastewater to the first recovery module. The third centrifuge is used to centrifuge the graphite after three purifications or after pressure filtration, and to transport the centrifuged acid solution to the acid solution collection unit and the centrifuged wastewater to the first recovery module.
5. The graphite purification system according to claim 4, characterized in that, Screens are provided between the third centrifuge and the acid collection unit, as well as between the third filter press and the acid collection unit.
6. The graphite purification system according to claim 4, characterized in that, The acid collection unit includes a first collection subunit and a second collection subunit. The first collection subunit is connected to the third centrifuge, and the second collection subunit is connected to the third filter press. The dosing unit includes a first metering subunit and a second metering subunit. The first metering subunit is connected to the first collection subunit and the acid mixing unit and is used to detect the amount of acid in the first collection subunit. The second metering subunit is connected to the second collection subunit and the acid mixing unit and is used to detect the amount of acid in the second collection subunit.
7. The graphite purification system according to claim 5, characterized in that, The mesh size of the sieve is greater than or equal to 1000 mesh.
8. The graphite purification system according to claim 1, characterized in that, The first acid purification module includes a first reaction vessel, a first filter press, a first centrifuge, and a dryer connected in sequence. The first reaction vessel is used to purify graphite and receive acid from the second recovery module. The first filter press is used to filter the graphite in the first reaction vessel and transport the filtered wastewater to the first recovery module. The first centrifuge is used to centrifuge the graphite in the first filter press and transport the centrifuged wastewater to the first recovery module. The dryer is connected to the alkali purification module and is used to dry the graphite in the first centrifuge and then transport it to the alkali purification module.
9. The graphite purification system according to claim 1, characterized in that, The alkali purification module includes a mixer, a rotary kiln, a second filter press, and a second centrifuge connected in sequence. The mixer is connected to the first acid purification module and is used to receive graphite after primary purification. The rotary kiln is used to dry the graphite. The second filter press is connected to both the rotary kiln and the first recovery module. The second filter press is used to filter the dried graphite and transport the filtered wastewater to the first recovery module. The second centrifuge is connected to both the second filter press and the first recovery module. The second centrifuge is used to centrifuge the filtered graphite and transport the centrifuged wastewater to the first recovery module.
10. The graphite purification system according to claim 1, characterized in that, The first recycling module includes a primary wastewater recycling unit, a secondary wastewater recycling unit, a tertiary wastewater recycling unit, and a neutralization treatment unit. The primary wastewater recycling unit is connected to the first acid purification module and the neutralization treatment unit, the secondary wastewater recycling unit is connected to the alkali purification module and the neutralization treatment unit, and the tertiary wastewater recycling unit is connected to the second acid purification module and the neutralization treatment unit. The neutralization treatment unit is used to neutralize the wastewater in the primary wastewater recycling unit, the secondary wastewater recycling unit, and the tertiary wastewater recycling unit.