Refining system of industrial-grade sodium carbonate
By combining metal membrane filtration and resin adsorption devices, the problem of short lifespan of PP filter cartridges is solved, achieving efficient and low-cost sodium carbonate refining, improving filtration efficiency and purity, and realizing deep resource recovery.
Patent Information
- Application Number
- CN202422856463.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-22
- Publication Date
- 2025-12-02
- Estimated Expiration
- 2034-11-22
AI Technical Summary
In existing sodium carbonate refining processes, PP filter cartridges have short lifespans, leading to frequent replacements, high costs, and difficulty in effectively removing fine impurities from the solution.
The system combines a metal membrane filtration device and a resin adsorption device, along with low-pressure steam heating and resource recovery technology. It efficiently removes impurities through metal membrane filtration, enhances the purification effect by using multiple resin adsorption columns, and achieves deep resource recovery by combining pressing and leaching treatments.
It extends the service life of filter elements, reduces maintenance and replacement costs, improves filtration efficiency and purity, achieves efficient sodium carbonate refining, and saves energy and resources.
Smart Images
Figure CN223620153U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of sodium carbonate refining, and more specifically, to a refining system for industrial-grade sodium carbonate. Background Technology
[0002] Industrial-grade sodium carbonate (Na₂CO₃) typically has a purity between 99% and 99.5%. Despite its high purity, it still contains trace amounts of impurities such as chloride ions, sulfate ions, calcium ions, magnesium ions, and particulate matter. Current methods for refining sodium carbonate typically involve the following steps: the dissolved industrial-grade sodium carbonate solution first enters a plate and frame filter press to remove particulate impurities, then passes through a PP cartridge filter to remove fine impurities, and finally undergoes deep purification in a resin to obtain a refined sodium carbonate solution.
[0003] Industrial-grade sodium carbonate has high purity and very low impurity content. However, the core function of a plate and frame filter press is slag removal. If an industrial-grade sodium carbonate solution is directly fed into a plate and frame filter press, a filter cake cannot form on the filter cloth. This results in all the small amount of impurities in the solution entering the filtrate and being discharged. Therefore, almost all impurities in the solution are removed by PP filter cartridges. However, PP filter cartridges lack backwashing or other regeneration functions. When the pressure differential of the PP filter cartridge rises to a certain level due to impurities, the cartridge reaches its service life limit and must be replaced. The used cartridges can only be disposed of as solid waste or hazardous waste. Therefore, the traditional sodium carbonate refining process results in a short lifespan for PP filter cartridges and high refining costs. Utility Model Content
[0004] The main purpose of this invention is to provide a refining system for industrial-grade sodium carbonate to solve the technical problem of short lifespan of PP filter cartridges in the prior art.
[0005] The purification system for industrial-grade sodium carbonate includes:
[0006] Sodium carbonate dissolving tank, used to dissolve industrial-grade sodium carbonate to obtain sodium carbonate stock solution;
[0007] A metal membrane filtration device is used to filter sodium carbonate stock solution to obtain concentrated and clear solutions; the inlet of the metal membrane filtration device is connected to the outlet of the sodium carbonate dissolving tank.
[0008] The pressing device is used to press the concentrated liquid to obtain a solid phase and a liquid phase; the inlet of the pressing device is connected to the concentrated liquid outlet of the metal membrane filter device.
[0009] The resin adsorption device is used to adsorb impurity ions in the clear liquid to obtain a refined sodium carbonate solution; the inlet of the resin adsorption device is connected to the clear liquid outlet of the metal membrane filter device.
[0010] Compared with the prior art, the refining system of this utility model has the following advantages: (1) The metal membrane has higher strength and durability, and can withstand repeated cleaning and regeneration. Using the metal membrane as the filter element can reduce the replacement frequency and maintenance cost, greatly extend the service life of the filter element, reduce the solid waste treatment cost of the waste filter element, reduce the operation of frequent filter element replacement, reduce operation and maintenance costs, save labor and downtime, and improve the overall operating efficiency and economy of the system. (2) Improved filtration efficiency: The metal membrane has high filtration accuracy and stable efficiency, and can efficiently remove fine particulate impurities in the solution, better protecting the subsequent resin adsorption device from the influence of particulate impurities. (3) High-efficiency purification: The combination of the metal membrane filter device and the resin adsorption device can more effectively remove various impurities in the solution, further improve the purity and quality of the sodium carbonate refining liquid, and meet the application requirements of higher standards. (4) The concentrated liquid is processed by the pressing device, which can effectively separate the solid phase and liquid phase, further reduce the impurity content in the liquid, reduce the burden of subsequent processing, and improve the processing capacity and efficiency of the system.
[0011] As a further improvement to the aforementioned industrial-grade sodium carbonate refining system, a first pipe is also included to introduce low-pressure steam into the sodium carbonate dissolving tank. This low-pressure steam effectively increases the solution temperature, accelerating the dissolution rate of industrial-grade sodium carbonate in water. Heating ensures complete dissolution of sodium carbonate, reducing the presence of undissolved particles and thus lessening the burden on subsequent filtration processes. The heated solution is typically more homogeneous, reducing localized oversaturation or undersaturation, ensuring solution uniformity and stability, and providing more stable operating conditions for subsequent filtration and purification processes. Furthermore, low-pressure steam is often a cheap byproduct of industrial processes; using it for heating saves energy costs and is more economical than electric heating or other heating methods.
[0012] As a further improvement to the aforementioned industrial-grade sodium carbonate refining system, a second pipe is also included to recirculate the liquid phase back to the sodium carbonate dissolving tank. This further ensures deeper resource recovery.
[0013] As a further improvement to the aforementioned industrial-grade sodium carbonate refining system, a third pipe is included for inputting pyrolysis mother liquor into the sodium carbonate dissolving tank, wherein the pyrolysis mother liquor is the mother liquor generated by the lithium extraction reaction. Preferably, the system further includes: a leaching device for leaching the solid phase to obtain a leachate; the inlet of the leaching device is connected to the solid phase outlet of the pressing device; a purification device for removing impurity ions from the leachate to obtain a low-concentration lithium solution; the inlet of the purification device is connected to the leachate from the leaching device; a concentration device for concentrating the low-concentration lithium solution to obtain a high-concentration lithium solution; the inlet of the concentration device is connected to the low-concentration lithium solution outlet of the purification device; and a lithium extraction device for extracting lithium from the high-concentration lithium solution to obtain lithium carbonate and pyrolysis mother liquor; the inlet of the lithium extraction device is connected to the high-concentration lithium solution outlet of the concentration device, and the outlet of the lithium extraction device is connected to the solvent inlet of the sodium carbonate dissolving tank. More preferably, the leaching device, purification device, concentration device, and lithium extraction device are derived from a lithium mica-to-lithium carbonate production system.
[0014] The applicant of this application filed a series of applications on May 30, 2024, such as 2024212191600, which described a technical solution for preparing lithium carbonate using lepidolite as raw material. In this process, sodium carbonate is used as a precipitant to precipitate lithium ions as lithium carbonate. Therefore, a large amount of thermal precipitation mother liquor is generated during the lithium extraction process, containing significant amounts of sodium carbonate and lithium resources. Therefore, this invention ingeniously combines the thermal precipitation mother liquor with the refining process of industrial-grade sodium carbonate, not only effectively recovering the sodium carbonate and lithium resources from the lithium extraction thermal precipitation mother liquor but also reducing the amount of water used to dissolve industrial-grade sodium carbonate, thus creating higher economic value.
[0015] As a further improvement to the aforementioned industrial-grade sodium carbonate refining system, a coarse filtration device is also included. The sodium carbonate raw solution undergoes coarse filtration before flowing into the metal membrane filtration device. This allows for the recovery of larger particles through the coarse filtration device, thereby increasing the processing pressure of the metal membrane filtration device.
[0016] As a further improvement to the aforementioned industrial-grade sodium carbonate refining system, the resin adsorption device includes a strong acid cation exchange resin adsorption column, a strong base anion exchange resin adsorption column, a weak acid cation exchange resin adsorption column, and a weak base anion exchange resin adsorption column arranged in series. Therefore, by combining multiple adsorption columns, the purification effect can be significantly improved, and the purity of the refined sodium carbonate solution can be increased.
[0017] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Additional aspects and advantages of the present invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present invention. Attached Figure Description
[0018] The accompanying drawings, which form part of this utility model, are used to aid in understanding this utility model. The contents provided in the drawings and their related descriptions in this utility model can be used to explain this utility model, but do not constitute an improper limitation of this utility model.
[0019] In the attached diagram:
[0020] Figure 1 This is a schematic diagram of the industrial-grade sodium carbonate refining system of Embodiment 1 of this utility model.
[0021] Figure 2 This is a schematic diagram of the industrial-grade sodium carbonate refining system of Embodiment 2 of this utility model.
[0022] Figure 3 This is a schematic diagram of the industrial-grade sodium carbonate refining system of Embodiment 3 of this utility model.
[0023] The relevant markings in the above figures are:
[0024] 100-Sodium carbonate dissolving tank, 200-Metal membrane filtration device, 300-Pressing device, 400-Resin adsorption device, 500-Coarse filtration device, 610-Leaching device, 620-Impurity removal device, 630-Concentration device, 640-Lithium extraction device. Detailed Implementation
[0025] The present invention will now be clearly and completely described in conjunction with the accompanying drawings. Those skilled in the art will be able to implement the present invention based on these descriptions. Before describing the present invention in conjunction with the accompanying drawings, it should be particularly noted that:
[0026] The technical solutions and features provided in the various parts of this utility model, including the following description, can be combined with each other without conflict.
[0027] Furthermore, the embodiments of the present invention described below are generally only a part of the embodiments of the present invention, and not all of the embodiments. Therefore, all other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the protection scope of the present invention.
[0028] Regarding the terminology and units used in this utility model: The terms "comprising," "having," and any variations thereof in the specification, claims, and related parts of this utility model are intended to cover non-exclusive inclusion.
[0029] Example 1
[0030] Figure 1This is a schematic diagram of the industrial-grade sodium carbonate refining system of this embodiment.
[0031] like Figure 1 As shown, the industrial-grade sodium carbonate refining system includes a sodium carbonate dissolving tank 100, a metal membrane filter 200, a pressing device 300, a resin adsorption device 400, a first pipeline, and a second pipeline. The sodium carbonate dissolving tank 100 is used to dissolve industrial-grade sodium carbonate to obtain a sodium carbonate stock solution (using water as a solvent). The metal membrane filter 200 is used to filter the sodium carbonate stock solution to obtain a concentrated solution and a clarified solution; the inlet of the metal membrane filter 200 is connected to the outlet of the sodium carbonate dissolving tank 100. The pressing device 300 is used to press the concentrated solution to obtain a solid phase and a liquid phase; the inlet of the pressing device 300 is connected to the concentrated solution outlet of the metal membrane filter 200. The resin adsorption device 400 is used to adsorb impurity ions in the clarified solution to obtain a refined sodium carbonate solution; the inlet of the resin adsorption device 400 is connected to the clarified solution outlet of the metal membrane filter 200. The first pipeline is used to input low-pressure steam into the sodium carbonate dissolving tank 100. The second pipe is used to return the liquid phase to the sodium carbonate dissolving tank 100.
[0032] The resin adsorption device 400 includes a strong acid cation exchange resin adsorption column, a strong base anion exchange resin adsorption column, a weak acid cation exchange resin adsorption column, and a weak base anion exchange resin adsorption column arranged in series.
[0033] Example 2
[0034] Figure 2 This is a schematic diagram of the industrial-grade sodium carbonate refining system of this embodiment.
[0035] Compared with Example 1, the purification system for industrial-grade sodium carbonate in this example differs in that: Figure 2 As shown, it also includes a coarse filtration device 500, through which the sodium carbonate raw solution is coarsely filtered before flowing into the metal membrane filtration device 200. The coarse filtration device 500 uses a sieve with an interception rate of ≥99% for particles with a size ≥80μm. The metal membrane filtration device 200 uses a sintered porous metal membrane with an interception rate of ≥99.5% for particles with a size ≥5μm.
[0036] Example 3
[0037] Figure 3 This is a schematic diagram of the industrial-grade sodium carbonate refining system of this embodiment.
[0038] Compared with Example 1, the purification system for industrial-grade sodium carbonate in this example differs in that: Figure 3As shown, the system also includes a third pipeline, a leaching device 610, a purification device 620, a concentration device 630, and a lithium extraction device 640. The third pipeline is used to input the thermal precipitation mother liquor as a solvent into the sodium carbonate dissolving tank 100. The leaching device 610 is used to leach the solid phase and obtain a leachate; the inlet of the leaching device 610 is connected to the solid phase outlet of the pressing device 300. The purification device 620 is used to remove impurity ions from the leachate and obtain a low-concentration lithium solution; the inlet of the purification device 620 is connected to the leachate from the leaching device 610. The concentration device 630 is used to concentrate the low-concentration lithium solution to obtain a high-concentration lithium solution; the inlet of the concentration device 630 is connected to the low-concentration lithium solution outlet of the purification device 620. The lithium extraction device 640 is used to extract lithium from high-concentration lithium liquid and obtain lithium carbonate and thermal precipitation mother liquor. The inlet of the lithium extraction device 640 is connected to the high-concentration lithium liquid outlet of the concentration device 630, and the outlet of the lithium extraction device 640 is connected to the solvent inlet of the sodium carbonate dissolving tank 100.
[0039] The leaching device 610, impurity removal device 620, concentration device 630 and lithium extraction device 640 are from the production system for producing lithium carbonate from lepidolite, see patent application number 2024212191600 for details.
[0040] The foregoing has described the relevant content of this utility model. Those skilled in the art will be able to implement this utility model based on these descriptions. All other embodiments obtained by those skilled in the art based on the above description of this utility model without inventive effort should fall within the protection scope of this utility model.
Claims
1. A purification system for industrial-grade sodium carbonate, characterized in that: include: Sodium carbonate dissolving tank (100) is used to dissolve industrial-grade sodium carbonate to obtain sodium carbonate stock solution; A metal membrane filter device (200) is used to filter sodium carbonate stock solution to obtain concentrated solution and clear solution; the inlet of the metal membrane filter device (200) is connected to the outlet of the sodium carbonate dissolving tank (100); A pressing device (300) is used to press the concentrated liquid to obtain a solid phase and a liquid phase; the inlet of the pressing device (300) is connected to the concentrated liquid outlet of the metal membrane filter device (200); A resin adsorption device (400) is used to adsorb impurity ions in the clear liquid to obtain sodium carbonate purified liquid; the inlet of the resin adsorption device (400) is connected to the clear liquid outlet of the metal membrane filter device (200).
2. The industrial-grade sodium carbonate refining system as described in claim 1, characterized in that: It also includes a first conduit for introducing low-pressure steam into a sodium carbonate dissolving tank (100).
3. The industrial-grade sodium carbonate refining system as described in claim 1, characterized in that: It also includes a second conduit for recirculating the liquid phase back into the sodium carbonate dissolving tank (100).
4. The industrial-grade sodium carbonate refining system as described in claim 1, characterized in that: It also includes a third pipe for feeding the hot-extraction mother liquor into the sodium carbonate dissolving tank (100), the hot-extraction mother liquor being the mother liquor generated by the lithium extraction reaction.
5. The industrial-grade sodium carbonate refining system as described in claim 4, characterized in that: Also includes: Leaching apparatus (610) is used to leach a solid phase to obtain a leachate; The feed inlet of the leaching device (610) is connected to the solid phase outlet of the pressing device (300); Impurity removal device (620) is used to remove impurity ions from the leachate to obtain a low-concentration lithium solution; The inlet of the impurity removal device (620) is connected to the leaching solution of the leaching device (610); A concentration device (630) is used to concentrate low-concentration lithium liquid to obtain high-concentration lithium liquid; The inlet of the concentration unit (630) is connected to the outlet of the low-concentration lithium liquid of the impurity removal unit (620); The lithium extraction device (640) is used to extract lithium from high-concentration lithium liquid to obtain lithium carbonate and thermal precipitation mother liquor. The inlet of the lithium extraction device (640) is connected to the high-concentration lithium liquid outlet of the concentration device (630), and the outlet of the lithium extraction device (640) is connected to the solvent inlet of the sodium carbonate dissolving tank (100).
6. The purification system for industrial-grade sodium carbonate as described in claim 5, characterized in that: The leaching device (610), impurity removal device (620), concentration device (630) and lithium extraction device (640) are from the lithium carbonate production system of lepidolite.
7. The industrial-grade sodium carbonate refining system as described in claim 1, characterized in that: It also includes a coarse filtration device (500), through which the sodium carbonate stock solution is coarsely filtered before flowing into the metal membrane filtration device (200).
8. The industrial-grade sodium carbonate refining system as described in claim 1, characterized in that: The resin adsorption device (400) includes a strong acid cation exchange resin adsorption column, a strong base anion exchange resin adsorption column, a weak acid cation exchange resin adsorption column, and a weak base anion exchange resin adsorption column arranged in series.