A resource-based treatment system and method for barium sulfide slag.

Abstract

This invention discloses a resource-based treatment system and method for barium sulfide slag. The system involves crushing and leaching the barium sulfide slag using a pretreatment unit, thereby leaching out the barium sulfide. The barium-enriched washing solution is then processed through an electrophoretic deep treatment unit to achieve high-value recovery of sulfur and barium elements, ultimately realizing the resource utilization of the barium slag. The entire process is pollution-free and has the advantages of being environmentally friendly, having high added value, high sulfur utilization efficiency, low cost, and simple operation. It is suitable for large-scale industrial applications and has broad market prospects and significant economic benefits.

Description

Technical Field

[0001] This invention relates to the treatment of barium slag solid waste, specifically to a resource-based treatment system and method for barium sulfide slag, belonging to the technical field of barium sulfide slag solid waste treatment. Background Technology

[0002] Barium slag is a solid residue produced during the carbonation-reduction process for producing barium carbonate and thiourea in the chemical industry. Currently, my country's barium slag emissions are approximately 1 million tons per year. The long-term accumulation of barium slag occupies a large amount of land resources and pollutes the environment, resulting in a significant waste of resources. Barium slag contains water-soluble barium and acid-soluble barium, and the leachate contains Ba... 2+ The concentration of barium slag exceeded the national standard limit by more than ten times, and the pH of the barium slag sample was close to or exceeded the standard limit (12.5), indicating alkaline corrosiveness. As is well known, barium (Ba) is a heavy metal element harmful to human health; inhalation or ingestion can cause acute barium poisoning. Furthermore, the sulfur in barium slag has an even stronger destructive effect on humans and the environment. When barium slag is leached by rainwater, the resulting toxic wastewater containing dissolved sulfides directly poisons surface water and groundwater. As it flows into rivers and reservoirs, it seeps into groundwater, threatening the health of residents' drinking water. In addition, the alkaline components in barium slag can also lead to soil salinization. Therefore, barium slag is explicitly listed as a hazardous waste in the "National Hazardous Waste List."

[0003] Barium slag contains various elements such as barium (Ba), magnesium (Mg), silicon (Si), oxygen (O), and sulfur (S). Barium exists primarily in barium carbonate, barium sulfate from unreacted barite, and unleached barium sulfide. Current technologies often employ acid leaching to recover barium from barium slag, involving the addition of hydrochloric acid, nitric acid, and sulfuric acid to obtain products such as barium chloride, barium nitrate, and barium sulfate. However, acid leaching not only consumes large amounts of strong acid but also generates significant amounts of acid fumes, seriously threatening worker safety and polluting the surrounding environment. Furthermore, during the acid leaching process, the presence of barium sulfide in the slag leads to the reaction of barium sulfide with acid, producing large amounts of hydrogen sulfide gas, further deteriorating the on-site and surrounding environment and exacerbating threats to worker health. It also wastes sulfur resources, preventing the effective utilization and treatment of sulfur ions in the barium slag. How to achieve the resource utilization of barium slag in a way that is both environmentally friendly and generates economic value is an urgent problem that needs to be solved. Summary of the Invention

[0004] To address the problems of existing barium sulfide slag treatment technologies, such as high acid consumption, high cost, high on-site working environment, significant environmental impact, and low product value due to insufficient recovery and utilization of sulfur ions, this invention provides a resource-based treatment system and method for barium sulfide slag. The system involves a pretreatment unit that crushes and leaches the barium sulfide slag with circulating water to extract barium sulfide. The barium-enriched washing solution is then processed through an electrophoretic deep treatment unit to convert barium into high-value nano-sized barium sulfate and sulfur into sodium sulfide. This achieves high-value resource utilization of barium slag, offering advantages such as environmental friendliness, high product added value, and high sulfur utilization efficiency.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is specifically described as follows:

[0006] According to a first embodiment of the present invention, a treatment system for the resource utilization of barium sulfide slag is provided.

[0007] A resource-based treatment system for barium sulfide slag includes a pretreatment unit and an electrophoretic deep treatment unit. The pretreatment unit comprises a crushing mechanism and a washing mechanism arranged in series. The electrophoretic deep treatment unit includes an electrolysis mechanism and a nanofiber membrane. The electrolysis mechanism includes an anode, a cathode, and an electrolytic cell. The anode and cathode are disposed within or inserted into the electrolytic cell. The nanofiber membrane is disposed inside the electrolytic cell, located between the anode and the cathode. The electrolytic cell has an anode inlet and a cathode inlet, wherein the anode inlet is located between the anode and the nanofiber membrane, and the cathode inlet is located between the nanofiber membrane and the cathode. The drain port of the washing mechanism is connected to the anode inlet via a pipe.

[0008] Preferably, a cation exchange membrane is provided between the anode and the anode inlet in the electrolytic cell. An anion exchange membrane is also provided between the cathode and the cathode inlet.

[0009] Preferably, the cathode inlet is connected to a sulfate solution storage tank via a liquid delivery pipeline. A flow control valve is also installed on the liquid delivery pipeline.

[0010] Preferably, multiple layers of the nanofiber membrane are disposed between the anode and the cathode. The gaps between the layers of the nanofiber membrane may be the same or different. The pore size of the nanofiber membrane is no greater than 500 nm, preferably no greater than 300 nm, and more preferably no greater than 200 nm.

[0011] Preferably, the system further includes an ultrasonic mechanism. The ultrasonic mechanism is disposed within the electrolytic cell and located between the multiple layers of the nanofiber membrane. It should be noted that the ultrasonic mechanism can be an ultrasonic rod, an ultrasonic generating block, an ultrasonic generating plate, or other ultrasonic-capable device.

[0012] Preferably, both the anode and cathode are carbon electrodes or other inert electrodes.

[0013] Preferably, the system also includes a post-processing unit, which comprises an outer tank, an inner tank, and a stirring mechanism. The outer tank is a closed cylindrical structure, and the inner tank is coaxially fitted inside the outer tank, with sieve holes on its side and bottom walls. The stirring mechanism is located inside the inner tank. A main feed inlet and a main liquid inlet are also provided on the top wall of the inner tank. The main feed inlet is connected to the discharge port of the electrolytic cell via a conveying pipe. The main liquid inlet is connected to a storage tank via a liquid inlet pipe.

[0014] Preferably, the stirring mechanism includes a stirring motor, a stirring shaft, and a stirring paddle. The stirring motor is mounted on the top wall of the outer barrel. The upper end of the stirring shaft is connected to the stirring motor, and its lower end extends downward through the top wall of the outer barrel and the top wall of the inner barrel, then into the interior of the inner barrel, or further downward through the bottom wall of the inner barrel, extending to the lower side of the bottom wall of the inner barrel. The stirring shaft is movably connected to the top wall of the outer barrel and the top or bottom wall of the inner barrel via bearings. The stirring paddle is mounted on the stirring shaft located below the top wall of the inner barrel.

[0015] Preferably, the stirring blade is an arc-shaped stirring blade, and serrated protrusions are provided on the side of the blade in the direction of rotation.

[0016] Preferably, the bottom of the outer barrel is designed as a tapered discharge port with a downward tapering opening. Ultrasonic blocks are evenly distributed on the bottom surface of the tapered discharge port in the circumferential direction.

[0017] Preferably, the aperture of the sieve is no greater than 200 nm, more preferably no greater than 180 nm, and even more preferably no greater than 150 nm.

[0018] According to a second embodiment of the present invention, a method for the resource-based treatment of barium sulfide slag is provided.

[0019] A method for the resource recovery of barium sulfide slag, or a method for resource recovery using the treatment system described in the first embodiment, comprising the following steps:

[0020] 1) The barium sulfide slag is crushed by a crushing mechanism, and then leached by a washing mechanism to obtain a leachate. The leached slag is disposed of separately, for example, for the production of barium salt products, or directly used as a building material.

[0021] 2) The leachate is fed into the electrolytic cell through the anode inlet, while the sulfate solution is fed into the electrolytic cell through the cathode inlet. The ultrasonic mechanism and power supply are started to carry out electrolysis.

[0022] 3) After electrolysis, the solid material deposited in the electrolytic cell is transported to the inner tank of the post-processing unit through the conveying pipe. Simultaneously, water and acid are added sequentially to the inner tank through the liquid inlet pipe. (It should be noted that water and acid are added separately. Water washing removes sodium sulfide and excess impurity ions carried by the nano-barium sulfate, while acid washing converts small amounts of other insoluble impurities generated during the reaction into barium sulfate, such as small amounts of barium thiosulfate, barium sulfite, barium sulfide, and residual barium carbonate.) The stirring mechanism and ultrasonic block are activated to stir the material in the post-processing unit. (The stirring time can be set according to the amount of material added, or stirring can be performed in multiple stages, for example, stirring for a period of time, allowing it to stand for observation, and then stirring again. Whether stirring all at once or in multiple stages, the ultimate goal is to ensure that all material can settle through the sieve holes of the inner tank and be transported to the outside with the liquid phase for solid-liquid separation.) After stirring, solid-liquid separation is performed. The solid phase is dried to obtain nano-barium sulfate. The residual liquid in the electrolytic cell is concentrated and crystallized to obtain sodium sulfide.

[0023] Preferably, in step 1), the mass concentration of barium sulfide in the barium sulfide slag is not less than 5%.

[0024] Preferably, in step 1), the water washing leaching is a multi-stage countercurrent circulating water washing leaching. The concentration of barium sulfide in the leaching solution is 0.5-1.5 mol / L.

[0025] Preferably, in step 2), the sulfate is sodium sulfate and / or sodium bisulfate. The concentration of the sulfate solution is 0.5-1.5 mol / L.

[0026] Preferably, in step 2), the power supply is a DC power supply with a voltage of 120-240V.

[0027] Preferably, in step 3), the acid is dilute sulfuric acid with a pH of 3-4 (dilute hydrochloric acid or dilute nitric acid may also be used, but dilute sulfuric acid is preferred). The amount of acid added is 2-10 times the mass of the solid material.

[0028] In this invention, the existing technology for treating barium sulfide slag suffers from serious environmental pollution, significant safety hazards, and underutilization of sulfur resources. The system first refines the barium sulfide slag using a crushing mechanism in the pretreatment unit to facilitate subsequent water washing and leaching of sulfides. Then, a three-stage countercurrent water washing process is employed for cyclic enrichment (the first-stage washing uses the second-stage washing filtrate or recycles the first-stage washing filtrate; the second-stage washing uses the third-stage washing filtrate; and the third-stage washing uses industrial water). This cyclic washing process maximizes the leaching of sulfur from the barium sulfide slag while conserving water resources, resulting in a high concentration of sulfur in the leaching solution. This concentration facilitates subsequent electrophoretic deep processing to produce high-value nano-barium sulfate and high-purity sodium sulfide products.

[0029] In this invention, an electrophoretic deep treatment unit is used to deeply treat the water-washed leachate of barium sulfide slag. The electrophoretic deep treatment unit includes an anode, a cathode, an electrolytic cell, and a nanofiber membrane. The nanofiber membrane is disposed inside the electrolytic cell, located between the anode and cathode. A leachate rich in barium sulfide is added to the anode side of the electrolytic cell, while a sodium sulfide solution is added to the cathode side. Utilizing the principle of electrolysis, an electrochemical method is applied to the recovery of sulfur from barium slag and the high-value conversion of barium. By controlling the applied current and voltage, barium ions in the barium sulfide solution are rapidly moved towards the cathode under the influence of the electric field, while sulfate ions in the sodium sulfate solution rapidly move towards the anode, thereby intensifying the reaction between barium ions and sulfate ions in the electrolytic cell and rapidly generating ultrafine barium sulfate precipitate. Compared to traditional devices that require pumps to increase the collision rate of materials, this invention offers ion selectivity, stable control, and ease of operation.

[0030] Furthermore, this invention incorporates a nanofiber membrane within the electrophoretic deep processing unit. During electrolysis, the nanofiber membrane provides nanochannels, forming a microreactor when barium and sulfate ions pass through. Barium and sulfate ion beams are ejected from the nanofiber membrane, much like numerous opposing showerheads, increasing the contact area and collision rate between anions and cations, instantly forming nanoscale barium sulfate, which precipitates between two nanofiber membrane layers. This yields a high-value nano-barium sulfate product with small particle size, uniform dispersion, and narrow particle size distribution. Sulfur remains in the liquid phase and can be recovered through subsequent processing to obtain high-purity sodium sulfide, thus achieving the separation and resource utilization of barium and sulfur elements in barium sulfide.

[0031] In this invention, at least two nanofiber membrane layers are typically arranged in the middle of the electrolytic cell of the electrophoretic deep treatment unit. The arrangement of multiple nanofiber membrane layers can, on the one hand, reduce the agglomeration of precipitated barium sulfate nanoparticles, and on the other hand, ensure that the generated barium sulfate nanoparticles are deposited between the nanofiber membrane layers. This prevents sulfate ions from passing through the two nanofiber membrane layers to enter the anode and generate barium sulfate near the anode, and barium ions from passing through the two nanofiber membrane layers to enter the cathode and generate barium sulfate at the cathode, which would cause difficulties in subsequent precipitation and separation. It should be noted that this invention also includes a cation exchange membrane between the anode and the nanofiber membrane, and an anion exchange membrane between the cathode and the nanofiber membrane. By introducing a cation exchange membrane around the anode, it prevents sulfur ions from moving towards the anode under the influence of the electric field, thus preventing oxidation and sulfur precipitation at the anode. It also helps to prevent oxygen generated at the anode from reacting with sodium sulfide, which would lead to impurities in the sodium sulfide. Introducing an anion exchange membrane around the cathode effectively prevents barium ions from entering the cathode and reacting with a large amount of hydroxide ions to produce barium hydroxide, which, if the concentration is too high, will precipitate as barium hydroxide crystals.

[0032] In this invention, an ultrasonic mechanism is further provided between the multiple nanofiber membrane layers. During the electrolysis process, ultrasonication is continuously performed. On the one hand, this can prevent the generated barium sulfate nanoparticles from adhering to the nanofiber membrane and causing blockage of the nanopores. On the other hand, it can also make the reaction between sulfate ions and barium ions more uniform, promote the generation and dispersion of barium sulfate nanoparticles, and reduce the agglomeration of barium sulfate nanoparticles. This is beneficial for obtaining high-value barium sulfate nanoparticles with narrow particle size distribution.

[0033] In this invention, the nano-barium sulfate obtained by electrolytic deposition still contains a certain amount of impurities (such as sodium sulfide and insoluble barium salts), and inevitably exhibits varying degrees of agglomeration, which greatly reduces the product value of the nano-barium sulfate. Therefore, to simultaneously ensure the purity of the nano-barium sulfate and completely prevent agglomeration, this invention abandons the traditional method of adding a dispersant during the reaction process (adding a dispersant introduces new impurities and reduces product purity). After obtaining the nano-barium sulfate from the electrolytic device, a special post-processing unit for the nano-barium sulfate is added. The post-processing unit includes an outer tank, an inner tank, a stirring mechanism, and an ultrasonic mechanism. The outer tank is a closed cylindrical structure, and the inner tank (with a...) The fully enclosed cylindrical structure with sieve holes is coaxially fitted inside the outer barrel, and sieve holes are also provided on the side and bottom walls of the inner barrel. The nano-barium sulfate deposited in the electrolytic cell is directly transported to the inner barrel of the post-processing unit through the conveying pipeline. Then, water is introduced sequentially to wash away sodium sulfide and other entrained impurities. After that, acid washing removes a small amount of other insoluble impurities. Under the dual action of stirring and ultrasound, it is further refined and screened to break up the agglomerated nano-barium sulfate. The post-processing unit integrates multiple functions such as washing, acidification, purification, refinement, and screening, which can further improve the purity, fineness, whiteness, viscosity and other indicators of nano-barium sulfate, effectively ensuring the product value of nano-barium sulfate.

[0034] In this invention, the nano-sized barium sulfate produced by electrolytic precipitation has high viscosity, high sulfide impurity content, and a yellowish tint. Due to agglomeration, the barium sulfate molecules, which are themselves nano-sized, combine to form larger barium sulfate particles. Therefore, improving the dispersion effect in subsequent processing is crucial. This invention uses a conical stirring mechanism to further refine the nano-barium sulfate. Multiple serrated stirring paddles and ultrasonic blocks inside the barrel can quickly disperse the nano-barium sulfate. The refined nano-sized barium sulfate is thrown out through the sieve holes in the inner cylinder. After acidification and washing, it sinks to the bottom of the cone, while the undispersed nano-sized barium sulfate in the inner cylinder continues to disperse until it is smaller than the sieve hole diameter before being thrown out. This ensures that the generated nano-sized barium sulfate particles have a stable and controllable size.

[0035] In this invention, the electrolysis process transforms the leachate from waste barium into nano-sized barium sulfate precipitate and sodium sulfide solution under the action of sulfates. The post-treatment process addresses issues related to the purity, fineness, whiteness, and viscosity of the nano-sized barium sulfate, particularly its purity. Only when the nano-sized barium sulfate is dispersed and the particle size is smaller does it contain fewer impurities, resulting in purer nano-sized barium sulfate and higher added value. The electrolysis and post-treatment processes are two indispensable steps in the production of nano-sized barium sulfate; neither can be omitted. Only when the barium sulfate obtained through the electrolysis process is at the nanoscale can it be further redispersed, washed, and sieved through ultrasonication and stirring to become a nano-sized barium sulfate product. Simultaneously, only through the subsequent post-treatment process can the agglomeration of the nano-sized barium sulfate obtained through the electrolysis process be prevented, and its purity and whiteness improved.

[0036] In this invention, the thickness of the anode is 0.1~100cm, preferably 0.5~80cm, more preferably 0.8~50cm. The thickness of the cathode is 0.1~100cm, preferably 0.5~80cm, more preferably 0.8~50cm. The length of the electrolytic cell is 0.1~100m, preferably 0.2~80m, more preferably 0.3~60m; the width of the electrolytic cell is 0.1~50m, preferably 0.2~40m, more preferably 0.3~30m; and the height of the electrolytic cell is 0.1~10m, more preferably 0.2~8m, more preferably 0.3~6m.

[0037] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0038] 1. This invention innovatively provides a resource-based treatment system for barium sulfide slag. Through the synergistic effect of a pretreatment unit, an electrophoretic deep treatment unit, and a post-treatment unit, the system separates barium sulfide from the barium sulfide slag, solidifies sulfur into high-purity sodium sulfide products, and converts barium into high-purity, high-value nano-barium sulfate products with narrow particle size distribution, thereby realizing the harmless resource utilization of barium slag.

[0039] 2. The resource recovery system described in this invention has a simple structure, low cost, no secondary pollution, simple operation, and generates high-value-added resource recovery products. It is suitable for large-scale industrial applications and has broad market prospects and significant economic benefits. Attached Figure Description

[0040] Figure 1 This is a simplified structural diagram of the system described in this invention.

[0041] Figure 2 This is a schematic diagram of the internal structure of the electrolytic cell described in this invention.

[0042] Figure 3This is a schematic diagram of the post-processing unit of the present invention.

[0043] Figure 4 This is a schematic diagram of the inner barrel structure of the present invention.

[0044] Figure 5 This is a top view of the stirring paddle of the present invention.

[0045] Figure 6 This is a flowchart of the method described in this invention.

[0046] Reference numerals: 1: Crushing mechanism; 2: Washing mechanism; 3: Electrolysis mechanism; 301: Anode; 302: Cathode; 303: Electrolytic cell; 304: Anode inlet; 305: Cathode inlet; 306: Cation membrane; 307: Anion membrane; 308: Feeding pipe; 4: Nanofiber membrane; 5: Sulfate solution storage tank; 501: Liquid delivery pipe; 502: Flow control valve; 6: Ultrasonic mechanism; 7: Outer tank; 8: Inner tank; 801: Sieve hole; 802: Main feed inlet; 803: Main liquid inlet; 804: Liquid inlet pipe; 9: Stirring mechanism; 901: Stirring motor; 902: Stirring shaft; 903: Stirring paddle; 904: Serrated protrusion; 10: Storage tank; 11: Ultrasonic block. Detailed Implementation

[0047] The technical solution of the present invention will be illustrated below with examples. The scope of protection sought by the present invention includes, but is not limited to, the following embodiments.

[0048] A resource-based treatment system for barium sulfide slag includes a pretreatment unit and an electrophoretic deep treatment unit. The pretreatment unit includes a crushing mechanism 1 and a washing mechanism 2 arranged in series. The electrophoretic deep treatment unit includes an electrolysis mechanism 3 and a nanofiber membrane 4. The electrolysis mechanism 3 includes an anode 301, a cathode 302, and an electrolytic cell 303. The anode 301 and cathode 302 are disposed within or inserted into the electrolytic cell 303. The nanofiber membrane 4 is disposed inside the electrolytic cell 303, located between the anode 301 and the cathode 302. The electrolytic cell 303 has an anode inlet 304 and a cathode inlet 305, wherein the anode inlet 304 is located between the anode 301 and the nanofiber membrane 4, and the cathode inlet 305 is located between the nanofiber membrane 4 and the cathode 302. The drain outlet of the washing mechanism 2 is connected to the anode inlet 304 via a pipe.

[0049] Preferably, a cation exchange membrane 306 is provided between the anode 301 and the anode inlet 304 in the electrolytic cell 303. An anion exchange membrane 307 is provided between the cathode 302 and the cathode inlet 305.

[0050] Preferably, the cathode inlet 305 is connected to the sulfate solution storage tank 5 via a liquid delivery pipe 501. A flow control valve 502 is also installed on the liquid delivery pipe 501.

[0051] Preferably, multiple layers of the nanofiber membrane 4 are disposed between the anode 301 and the cathode 302. The gaps between the layers of the multiple nanofiber membrane 4 may be the same or different. The pore size of the nanofiber membrane 4 is not greater than 500 nm, preferably not greater than 300 nm, and more preferably not greater than 200 nm.

[0052] Preferably, the system also includes an ultrasonic mechanism 6. The ultrasonic mechanism 6 is disposed within the electrolytic cell 303 and is located in the middle of the multiple nanofiber membranes 4.

[0053] Preferably, both the anode 301 and the cathode 302 are carbon electrodes.

[0054] Preferably, the system also includes a post-processing unit, which comprises an outer barrel 7, an inner barrel 8, and a stirring mechanism 9. The outer barrel 7 is a closed cylindrical structure, and the inner barrel 8 is coaxially fitted inside the outer barrel 7, with sieve holes 801 on both the side and bottom walls of the inner barrel 8. The stirring mechanism 9 is located inside the inner barrel 8. The top wall of the inner barrel 8 also has a main feed inlet 802 and a main liquid inlet 803. The main feed inlet 802 is connected to the discharge port of the electrolytic cell 303 via a conveying pipe 308. The main liquid inlet 803 is connected to the storage tank 10 via a liquid inlet pipe 804.

[0055] Preferably, the stirring mechanism 9 includes a stirring motor 901, a stirring shaft 902, and a stirring paddle 903. The stirring motor 901 is mounted on the top wall of the outer barrel 7. The upper end of the stirring shaft 902 is connected to the stirring motor 901, and its lower end extends downward through the top wall of the outer barrel 7 and the top wall of the inner barrel 8, then into the interior of the inner barrel 8, or further downward through the bottom wall of the inner barrel 8, extending to the lower side of the bottom wall of the inner barrel 8. The stirring shaft 902 is movably connected to the top wall of the outer barrel 7 and the top or bottom wall of the inner barrel 8 via bearings. The stirring paddle 903 is mounted on the stirring shaft 902 located below the top wall of the inner barrel 8.

[0056] Preferably, the stirring blade 903 is an arc-shaped stirring blade, and a serrated protrusion 904 is provided on the side of the blade in the direction of rotation.

[0057] Preferably, the bottom of the outer barrel 7 is designed as a tapered discharge port with a downward tapering opening. Ultrasonic blocks 11 are evenly distributed on the bottom surface of the tapered discharge port in the circumferential direction.

[0058] Preferably, the aperture of the sieve 801 is no greater than 200 nm. Example 1

[0059] like Figure 1-5 As shown, a resource-based treatment system for barium sulfide slag includes a pretreatment unit and an electrophoretic deep treatment unit. The pretreatment unit includes a crushing mechanism 1 and a washing mechanism 2 arranged in series. The electrophoretic deep treatment unit includes an electrolysis mechanism 3 and a nanofiber membrane 4. The electrolysis mechanism 3 includes an anode 301, a cathode 302, and an electrolytic cell 303. The anode 301 and cathode 302 are disposed within or inserted into the electrolytic cell 303. The nanofiber membrane 4 is disposed inside the electrolytic cell 303, located between the anode 301 and the cathode 302. The electrolytic cell 303 has an anode inlet 304 and a cathode inlet 305, wherein the anode inlet 304 is located between the anode 301 and the nanofiber membrane 4, and the cathode inlet 305 is located between the nanofiber membrane 4 and the cathode 302. The drain outlet of the washing mechanism 2 is connected to the anode inlet 304 via a pipe. Example 2

[0060] The process is repeated in Example 1, except that a cation exchange membrane 306 is also provided between the anode 301 and the anode inlet 304 in the electrolytic cell 303. An anion exchange membrane 307 is also provided between the cathode 302 and the cathode inlet 305. Example 3

[0061] Example 2 is repeated, except that the cathode inlet 305 is connected to the sulfate solution storage tank 5 via a liquid delivery pipe 501. A flow control valve 502 is also installed on the liquid delivery pipe 501. Example 4

[0062] Example 3 is repeated, except that multiple layers of the aforementioned nanofiber membrane 4 are disposed between the anode 301 and the cathode 302. The gaps between the layers of the multiple nanofiber membrane 4 may be the same or different. The pore size of the nanofiber membrane 4 is no greater than 200 nm. Example 5

[0063] The system is a repeat of Example 4, except that it also includes an ultrasonic mechanism 6. The ultrasonic mechanism 6 is disposed within the electrolytic cell 303 and is located in the middle of the multiple nanofiber membranes 4. Example 6

[0064] Example 5 is repeated, except that both the anode 301 and the cathode 302 are carbon electrodes. Example 7

[0065] The system repeats Embodiment 6, except that it also includes a post-processing unit, which comprises an outer barrel 7, an inner barrel 8, and a stirring mechanism 9. The outer barrel 7 is a closed cylindrical structure, and the inner barrel 8 is coaxially fitted inside the outer barrel 7. The inner barrel 8 has sieve holes 801 on its side walls and bottom walls. The stirring mechanism 9 is located inside the inner barrel 8. The top wall of the inner barrel 8 also has a main feed inlet 802 and a main liquid inlet 803. The main feed inlet 802 is connected to the discharge port of the electrolytic cell 303 via a conveying pipe 308. The main liquid inlet 803 is connected to the storage tank 10 via a liquid inlet pipe 804. Example 8

[0066] The embodiment 7 is repeated, except that the stirring mechanism 9 includes a stirring motor 901, a stirring shaft 902, and a stirring paddle 903. The stirring motor 901 is mounted on the top wall of the outer barrel 7. The upper end of the stirring shaft 902 is connected to the stirring motor 901, and its lower end extends downward through the top wall of the outer barrel 7 and the top wall of the inner barrel 8, then into the interior of the inner barrel 8, or further downward through the bottom wall of the inner barrel 8, then to the lower side of the bottom wall of the inner barrel 8. The stirring shaft 902 is movably connected to the top wall of the outer barrel 7 and the top or bottom wall of the inner barrel 8 via bearings. The stirring paddle 903 is mounted on the stirring shaft 902 located below the top wall of the inner barrel 8. Example 9

[0067] Repeat Example 8, except that the stirring paddle 903 is an arc-shaped stirring blade, and a serrated protrusion 904 is provided on the side of the blade in the direction of rotation. Example 10

[0068] The same principle applies to embodiment 9, except that the bottom of the outer barrel 7 is designed as a tapered discharge port with a downward tapering opening. Ultrasonic blocks 11 are evenly distributed on the bottom surface of the tapered discharge port in the circumferential direction. Example 11

[0069] Repeat Example 10, except that the aperture of the sieve 801 is no greater than 120 nm.

[0070] Application Example 1

[0071] The resource recovery system for barium sulfide slag described in Example 10 was used to process a certain barium sulfide slag for resource recovery. The process is as follows:

[0072] The composition of the barium sulfide slag is as follows: barium sulfide 20.3%, barium carbonate 17.5%, barium sulfate 15.3%, silicon dioxide 25.1%, H2O 15.5%, and C 6.2%.

[0073] 1) After crushing 100 kg of the above barium sulfide slag into powder, it is subjected to three-stage countercurrent circulating water washing and leaching until the concentration of barium sulfide in the obtained leachate is not less than 0.5 mol / L.

[0074] 2) 10L of leachate is fed into the electrolytic cell 303 located between the cation exchange membrane 306 and the nanofiber membrane 4 via the anode inlet 304. Simultaneously, 10L of sodium sulfate solution of the same concentration is fed into the electrolytic cell 303 located between the anion exchange membrane 307 and the nanofiber membrane 4 via the cathode inlet 305. The ultrasonic mechanism 6 and the power supply (220V DC power supply) are activated simultaneously for electrolysis.

[0075] 3) After electrolysis, the solid material deposited in the electrolytic cell 303 is filtered out and transported to the inner tank 8 of the post-processing unit through the conveying pipe 308. At the same time, water is added to the inner tank 8 through the liquid inlet pipe 804 for water washing (liquid-solid ratio of 6:1). After the water is discharged (recycled for the water washing water in step 1), dilute sulfuric acid with pH of 3-4 is introduced for acid washing (liquid-solid ratio of 6:1). The stirring mechanism and ultrasonic block 11 are started for stirring. After stirring, the mixture is allowed to settle and the solid material deposited at the bottom of the outer tank 7 is discharged. After drying, a barium sulfate nanoparticle product with a purity of 99.5% and an average particle size of 9nm is obtained, with a yield of 90.5%.

[0076] The residual liquid in the electrolytic cell 303 was concentrated and crystallized to obtain sodium sulfide product with a purity of 61.28% and a yield of 80.25%.

[0077] Application Example 2

[0078] The resource recovery system for barium sulfide slag described in Example 10 was used to process a certain barium sulfide slag for resource recovery. The process is as follows:

[0079] The composition of barium sulfide slag is as follows: barium sulfide 20.3%, barium carbonate 17.5%, barium sulfate 15.3%, silicon dioxide 25.1%, H2O 15.5%, and C 6.2%.

[0080] 1) After crushing 130 kg of the above barium sulfide slag into powder, it is subjected to three-stage countercurrent circulating water washing and leaching until the concentration of barium sulfide in the obtained leachate is not less than 0.8 mol / L.

[0081] 2) 15L of leachate is fed into the electrolytic cell 303 located between the cation exchange membrane 306 and the nanofiber membrane 4 via the anode inlet 304. Simultaneously, 15L of sodium sulfate solution of the same concentration is fed into the electrolytic cell 303 located between the anion exchange membrane 307 and the nanofiber membrane 4 via the cathode inlet 305. The ultrasonic mechanism 6 and the power supply (220V DC power supply) are activated simultaneously for electrolysis.

[0082] 3) After electrolysis, the solid material deposited in the electrolytic cell 303 is filtered out and transported to the inner tank 8 of the post-processing unit through the conveying pipe 308. At the same time, water is added to the inner tank 8 through the liquid inlet pipe 804 for water washing (liquid-solid ratio of 8:1). After the water is discharged (recycled for the water washing water in step 1), dilute sulfuric acid with pH of 3-4 is introduced for acid washing (liquid-solid ratio of 8:1). The stirring mechanism and ultrasonic block 11 are started for stirring. After stirring, the mixture is allowed to settle and the solid material deposited at the bottom of the outer tank 7 is discharged. After drying, a barium sulfate product with a purity of 99.6% and an average particle size of 6nm is obtained, with a yield of 89.3%.

[0083] The residual liquid in the electrolytic cell 303 was concentrated and crystallized to obtain sodium sulfide product with a purity of 62.3% and a yield of 82.13%.

[0084] Comparative Example 1

[0085] The composition of barium sulfide slag is as follows: barium sulfide 20.3%, barium carbonate 17.5%, barium sulfate 15.3%, silicon dioxide 25.1%, H2O 15.5%, and C 6.2%.

[0086] 1) After crushing 130 kg of the above barium sulfide slag into powder, it is subjected to three-stage countercurrent circulating water washing and leaching until the concentration of barium sulfide in the obtained leachate is not less than 0.8 mol / L.

[0087] 2) 15L of leachate is fed into the electrolytic cell 303 located between the cation exchange membrane 306 and the nanofiber membrane 4 via the anode inlet 304. Simultaneously, 15L of sodium sulfate solution of the same concentration is fed into the electrolytic cell 303 located between the anion exchange membrane 307 and the nanofiber membrane 4 via the cathode inlet 305. The ultrasonic mechanism 6 and the power supply (220V DC power supply) are activated simultaneously for electrolysis.

[0088] 3) After electrolysis, the solid material deposited in the electrolytic cell 303 is filtered out, dried, and then the barium sulfate nanoparticles with a purity of 93.3% and an average particle size of 525nm are obtained with a yield of 95.6%.

[0089] The residual liquid in the electrolytic cell 303 was concentrated and crystallized to obtain sodium sulfide product with a purity of 61.85% and a yield of 70.62%.

[0090] As can be seen from Comparative Example 1, compared with Application Examples 1 and 2, the product of Comparative Example 1 has a high impurity content, low purity of nano-barium sulfate, serious agglomeration, large particle size, and the entrained sodium sulfide cannot be washed and recovered by water, resulting in a low sodium sulfide recovery rate.

[0091] Comparative Example 2

[0092] The composition of barium sulfide slag is as follows: barium sulfide 20.3%, barium carbonate 17.5%, barium sulfate 15.3%, silicon dioxide 25.1%, H2O 15.5%, and C 6.2%.

[0093] 1) After crushing 130 kg of the above barium sulfide slag into powder, it is subjected to three-stage countercurrent circulating water washing and leaching until the concentration of barium sulfide in the obtained leachate is not less than 0.8 mol / L.

[0094] 2) Mix 15L of leachate with 15L of sodium sulfate solution of the same concentration for reaction.

[0095] 3) After the reaction is complete, the solid material is filtered out and transported to the inner tank 8 of the post-processing unit through the conveying pipe 308. At the same time, water is added to the inner tank 8 through the liquid inlet pipe 804 for water washing (liquid-solid ratio of 8:1). After the water is discharged, dilute sulfuric acid with pH of 3-4 is introduced for acid washing (liquid-solid ratio of 8:1). The stirring mechanism and ultrasonic block 11 are started for stirring. After stirring is completed, the mixture is allowed to settle and the solid material deposited at the bottom of the outer tank 7 is discharged. After drying, a product with a purity of 95.35% and an average particle size of 3250nm is obtained, which is a nano barium sulfate product.

[0096] The residual liquid in electrolytic cell 303 was concentrated and crystallized to obtain sodium sulfide product with a purity of 62.35% and a yield of 76.32%.

[0097] As can be seen from Comparative Example 2, compared with Application Examples 1 and 2, Comparative Example 1 did not obtain nano-sized barium sulfate. The barium sulfate agglomerates were generally large in size (not passing through the nano-sieve or very few passing through the sieve). Due to the large size of the barium sulfate particles, sodium sulfide was severely entrained, resulting in a low sodium sulfide recovery rate.

[0098] Comparative Example 3

[0099] The composition of barium sulfide slag is as follows: barium sulfide 20.3%, barium carbonate 17.5%, barium sulfate 15.3%, silicon dioxide 25.1%, H2O 15.5%, and C 6.2%.

[0100] 1) After crushing 130 kg of the above barium sulfide slag into powder, it is subjected to three-stage countercurrent circulating water washing and leaching until the concentration of barium sulfide in the obtained leachate is not less than 0.8 mol / L.

[0101] 2) 15L of leachate is fed into the electrolytic cell 303 located between the cation exchange membrane 306 and the nanofiber membrane 4 via the anode inlet 304. Simultaneously, 15L of sodium sulfate solution of the same concentration is fed into the electrolytic cell 303 located between the anion exchange membrane 307 and the nanofiber membrane 4 via the cathode inlet 305. The ultrasonic mechanism 6 and the power supply (220V DC power supply) are activated simultaneously for electrolysis.

[0102] 3) After electrolysis, the solid material deposited in the electrolytic cell 303 is filtered out and transported to a stirring tank equipped with only a stirring mechanism. Water (liquid-solid ratio of 8:1) is added and stirred. After stirring, the mixture is allowed to settle, the precipitate is filtered out, and after drying, a nano barium sulfate product with a purity of 98.36% and an average particle size of 35nm is obtained, with a yield of 92.35%.

[0103] The residual liquid in the electrolytic cell 303 was concentrated and crystallized to obtain sodium sulfide product with a purity of 62.25% and a yield of 83.25%.

[0104] As can be seen from Comparative Example 3, compared with Application Examples 1 and 2, the product of Comparative Example 3 has a higher impurity content and lower purity of nano-barium sulfate.

Claims

1. A system for the resource recovery of barium sulphide residue, characterised in that: The system includes a pretreatment unit and an electrophoretic deep treatment unit; wherein, the pretreatment unit includes a crushing mechanism (1) and a washing mechanism (2) arranged in series; the electrophoretic deep treatment unit includes an electrolysis mechanism (3) and a nanofiber membrane (4); the electrolysis mechanism (3) includes an anode (301), a cathode (302) and an electrolytic cell (303), the anode (301) and the cathode (302) being disposed within or inserted into the electrolytic cell (303); the nanofiber membrane (4) is disposed inside the electrolytic cell (303) and located between the anode (301) and the cathode (302); electrolysis The tank (303) is provided with an anode inlet (304) and a cathode inlet (305), wherein: the anode inlet (304) is located between the anode (301) and the nanofiber membrane (4), and the cathode inlet (305) is located between the nanofiber membrane (4) and the cathode (302); the drain port of the washing mechanism (2) is connected to the anode inlet (304) through a pipe; multiple layers of the nanofiber membrane (4) are provided between the anode (301) and the cathode (302); the gaps between the layers of the multiple nanofiber membrane (4) are the same or different; the pore size of the nanofiber membrane (4) is not greater than 500nm; Inside the electrolytic cell (303), a cation exchange membrane (306) is provided between the anode (301) and the anode inlet (304); an anion exchange membrane (307) is provided between the cathode (302) and the cathode inlet (305); the cathode inlet (305) is connected to the sulfate solution storage tank (5) via a liquid delivery pipe (501); a flow control valve (502) is also provided on the liquid delivery pipe (501); the system also includes a post-processing unit, which includes an outer tank (7), an inner tank (8), and a stirring mechanism ( 9); the outer barrel (7) is a closed cylindrical structure, and the inner barrel (8) is coaxially sleeved inside the outer barrel (7), and sieve holes (801) are opened on the side wall and bottom wall of the inner barrel (8); the stirring mechanism (9) is set inside the inner barrel (8); the top wall of the inner barrel (8) is also provided with a main feed port (802) and a main liquid inlet (803); the main feed port (802) is connected to the discharge port of the electrolytic cell (303) through the conveying pipe (308); the main liquid inlet (803) is connected to the storage tank (10) through the liquid inlet pipe (804); The method for resource-based treatment of barium sulfide slag using the above-mentioned barium sulfide slag resource-based treatment system includes the following steps: 1) The barium sulfide slag is crushed by the crushing mechanism (1), and then leached by the washing mechanism (2) to obtain leachate; 2) The leachate is transported to the electrolytic cell (303) through the anode feed port (304), and the sulfate solution is transported to the electrolytic cell (303) through the cathode feed port (305); The ultrasonic mechanism (6) and the power supply are started for electrolysis; 3) Electrolysis After completion, the solid material deposited in the electrolytic cell (303) is transported to the inner tank (8) of the post-processing unit through the conveying pipe (308). At the same time, water and acid are added to the inner tank (8) in sequence through the liquid inlet pipe (804), and the stirring mechanism (9) and ultrasonic block (11) are started to stir the material in the post-processing unit. After stirring, solid-liquid separation is performed. After the solid phase is dried, nano barium sulfate can be obtained. The residual liquid in the electrolytic cell (303) is concentrated and crystallized to obtain sodium sulfide.

2. The system according to claim 1, characterized in that: The pore size of the nanofiber membrane (4) is no greater than 300 nm.

3. The system according to claim 2, characterized in that: The pore size of the nanofiber membrane (4) is no greater than 200 nm.

4. The system according to any one of claims 1-3, characterized in that: The system also includes an ultrasonic mechanism (6); the ultrasonic mechanism (6) is disposed within the electrolytic cell (303) and located in the middle of the multilayer nanofiber membrane (4); and / or Both the anode (301) and the cathode (302) are carbon electrodes.

5. The system according to claim 1, characterized in that: The stirring mechanism (9) includes a stirring motor (901), a stirring shaft (902), and a stirring paddle (903); the stirring motor (901) is installed on the top wall of the outer barrel (7); the upper end of the stirring shaft (902) is connected to the stirring motor (901), and its lower end extends downward through the top wall of the outer barrel (7) and the top wall of the inner barrel (8) to the interior of the inner barrel (8) or further downward through the bottom wall of the inner barrel (8) to the lower side of the bottom wall of the inner barrel (8), and the stirring shaft (902) is movably connected to the top wall of the outer barrel (7) and the top or bottom wall of the inner barrel (8) through bearings; the stirring paddle (903) is installed on the stirring shaft (902) located below the top wall of the inner barrel (8).

6. The system according to claim 5, characterized in that: The stirring blade (903) is an arc-shaped stirring blade, and serrated protrusions (904) are also provided on the side of the blade in the direction of rotation; and / or The bottom of the outer barrel (7) is designed as a tapered discharge port with a downward tapering opening; ultrasonic blocks (11) are evenly distributed on the bottom surface of the tapered discharge port in the circumferential direction; and / or The aperture of the sieve (801) is no greater than 200 nm.

7. The system according to claim 1, characterized in that: In step 1), the mass concentration of barium sulfide in the barium sulfide slag is not less than 5%; and / or The water washing leaching is a multi-stage countercurrent circulating water washing leaching; the concentration of barium sulfide in the leaching solution is 0.5-1.5 mol / L.

8. The system according to claim 7, characterized in that: In step 2), the sulfate is sodium sulfate and / or sodium bisulfate; the concentration of the sulfate solution is 0.5-1.5 mol / L; and / or In step 2), the power supply is a DC power supply with a voltage of 120-240V; and / or In step 3), the acid is dilute sulfuric acid with a pH of 3-4; the amount of acid added is 2-10 times the mass of the solid material.

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