A device for preparing a phosphogypsum-based ecological restoration material

Abstract

The utility model discloses a kind of phosphogypsum-based ecological restoration material preparation devices, it is related to phosphogypsum-based ecological restoration material preparation technical field.The device is composed of raw material pretreatment, biological inoculation, compound modification, granulation forming and biological activation five big systems;Pretreatment system is integrated in one body with crushing, screening, impurity ion removal-evaporation crystallization and neutralization adjustment, realize phosphogypsum deep purification;Biological inoculation system online culture and reserve functional flora;Compound modification system accurate control quantity uniform mixing;Granulation forming system completes granulation, screening and coating, obtains the granule of high strength, uniform particle size;Biological activation system carries out rapid activation to granule, improves product biological activity.The device has the advantages of improving phosphogypsum impurity removal rate, reducing energy consumption, improving microbial activity, product stability, quality closed-loop control etc., realizes the dual goal of waste resource utilization and ecological environment restoration.

Description

Technical Field

[0001] This utility model relates to the field of phosphogypsum-based ecological restoration material preparation technology, and in particular to a phosphogypsum-based ecological restoration material preparation device applied to the field of ecological restoration material preparation technology. Background Technology

[0002] Phosphogypsum is an industrial byproduct generated during the wet-process phosphoric acid production. my country produces a large amount of phosphogypsum annually, but its comprehensive utilization rate is low. Long-term stockpiling of large quantities of phosphogypsum not only occupies land resources but also poses environmental pollution risks. Therefore, the resource utilization of phosphogypsum has become an important issue that urgently needs to be addressed.

[0003] With the deepening of ecological civilization construction in my country, the demand for soil pollution remediation and ecological environment governance is becoming increasingly urgent. Phosphogypsum, whose main component is calcium sulfate dihydrate (CaSO4·2H2O), is rich in calcium and sulfur elements necessary for plant growth and can be used as a soil conditioner after appropriate treatment. At the same time, phosphogypsum has a porous structure and a certain ion exchange capacity, providing a carrier for beneficial microorganisms, making it an excellent base material for preparing bioactive ecological restoration materials.

[0004] The current methods for preparing ecological restoration materials mainly include: (1) physical modification method, which improves the material properties through physical means such as crushing and granulation, but lacks biological activity and has limited restoration effect; (2) chemical modification method, which adds chemical modifiers to adjust the material properties, but is prone to secondary pollution and has poor environmental friendliness; (3) biological modification method, which inoculates microorganisms to improve the material activity, but the survival rate of microorganisms in the existing technology is low and the activity maintenance time is short.

[0005] Existing ecological restoration material preparation equipment suffers from problems such as low removal rate of phosphogypsum impurities, high energy consumption, limited equipment functionality, difficulty in maintaining microbial activity, unstable products, and lack of closed-loop quality control in production.

[0006] Therefore, developing an ecological restoration material preparation device that integrates phosphogypsum pretreatment, microbial culture and inoculation, compound modification, granulation and molding, and bioactivation is of great practical significance and broad application prospects for improving the resource utilization level of phosphogypsum and promoting the development of the ecological environment restoration industry. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the existing technology and propose a device for preparing phosphogypsum-based ecological restoration materials to solve the above-mentioned problems.

[0008] To address the aforementioned issues, this invention provides a device for preparing phosphogypsum-based ecological restoration materials, comprising a raw material pretreatment system, a biological inoculation system, a compound modification system, a granulation and molding system, and a biological activation system. The raw material pretreatment system and the biological inoculation system are respectively connected to the compound modification system, and the compound modification system is sequentially connected to the granulation and molding system and the biological activation system. The raw material pretreatment system includes a phosphogypsum storage silo, a crushing and screening machine, an impurity ion removal device, and a neutralization and conditioning tank connected in sequence. The impurity ion removal device includes a feed inlet, a cation exchange column fixedly connected to the bottom of the feed inlet, a top cover fixedly connected to the outer end of the cation exchange column, and an anion exchange column, an annular support plate, a heating ring, a vacuum evaporation ring, and an outer shell coaxially sleeved on the outer side of the cation exchange column. There are gaps at the bottom of the cation exchange column and the bottom of the anion exchange column, and there are annular gaps between adjacent cation exchange columns, anion exchange columns, and annular support plates. The top of the annular support plate is located below the top of the anion exchange column; The vacuum evaporation ring has a hollow cylindrical structure. A crystallizer is fixedly connected to the bottom end of the vacuum evaporation ring, and a discharge port is fixedly connected to the bottom end of the crystallizer. The top of the anion exchange column and the outer shell are fixedly connected to the bottom of the top cover. The anion exchange column, the annular support plate, the vacuum evaporation ring, and the bottom of the outer shell are all fixedly connected to the crystallizer. A vacuum evaporation chamber is formed between the top cover, the anion exchange column, the crystallizer, and the outer shell; The top cover has a vacuum port, which is connected to the vacuum evaporation chamber. The biological inoculation system includes a nutrient solution preparation tank, a bacterial culture tank, and a bacterial solution storage tank connected in sequence; The compound modification system includes a biaxial mixer, which is connected to the neutralization and conditioning tank and the bacterial liquid storage tank via pipelines; The granulation system includes a granulator, a screening device, and a coating device connected in sequence. The bio-activation system includes a fermentation activation tank, an aging chamber, and a quality testing device connected in sequence.

[0009] The cation exchange column is a hollow cylindrical structure. The inner wall of the cation exchange column is fixedly connected with a multi-layer plate structure. The multi-layer plate structure is an alternating structure with gaps between the plates and notches in the plate structure. The plate structure is made of porous material, and both the plate structure and the interior of the cation exchange column are filled with cation exchange resin.

[0010] The anion exchange column is made of porous material and filled with anion exchange resin.

[0011] The phosphogypsum storage silo has a cylindrical structure with a conical discharge port at the bottom.

[0012] The microbial culture tank includes a fermentation tank body, a stirring system, a ventilation system, and a temperature control system. The stirring system is a paddle mixer, and the microbial liquid storage tank is connected to the microbial culture tank through a pipeline.

[0013] The twin-shaft mixer includes a U-shaped mixing tank, a twin-shaft agitator, and multiple feed ports. The twin-shaft agitator consists of two parallel shafts with ribbon blades. The feed ports are located at the top of the tank. The compound modification system also includes an organic matter additive device and a mineral feeder, all of which are connected to the twin-shaft mixer via pipelines.

[0014] The granulator includes a granulation disc, a spray system, a baffle ring, and a dust removal device.

[0015] The fermentation activation tank includes a cylindrical tank, a temperature control system, a humidity control system, and a ventilation system.

[0016] The device also includes a steam generator, an air purification system, a wastewater treatment device, and an automatic packaging machine. The steam generator is connected to the microbial culture tank and the fermentation activation tank via steam pipes.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The impurity ion removal device achieves deep removal of impurities from phosphogypsum by re-exchanging ions after water washing and resolution, further improving the removal rate of impurity ions in phosphogypsum. It also removes harmful cations and anions. By combining vacuum evaporation crystallization technology, it achieves integrated processing of deep impurity removal by ion exchange and efficient concentration by evaporation crystallization, effectively improving processing efficiency and reducing energy consumption. Microbial culture is carried out in a culture tank to increase the number of microorganisms; after coating, the microorganisms are activated again in a fermentation activation tank to enhance their biological activity; and a quality testing device performs multi-index testing on the product to achieve the full-process maintenance of microbial activity and closed-loop control of product quality, resulting in the beneficial effects of high product activity and long shelf life. The twin-shaft mixer uses two parallel shafts with spiral blades to rotate, which makes the components evenly dispersed and avoids the dead corners and uneven mixing problems of traditional mixing equipment. Through continuous production design, the production efficiency is increased by 3-5 times compared to traditional intermittent equipment, meeting the needs of large-scale industrial production. By combining biological inoculation technology with physicochemical modification, the prepared ecological restoration material has multiple functions such as soil improvement, nitrogen fixation, phosphorus solubilization, and antibacterial properties. Its restoration effect is significantly better than that of traditional materials, realizing the transformation of phosphogypsum industrial waste into high-value-added ecological restoration materials. The economic and environmental benefits are significant, opening up new avenues for the resource utilization of phosphogypsum. Attached Figure Description

[0018] Figure 1 This is a structural diagram of the appearance of this application; Figure 2 This is an exploded view of the entire application; Figure 3 For the local explosion of this application Figure 1 ; Figure 4 For the local explosion of this application Figure 2 ; Figure 5 This is a front view of this application; Figure 6 For the purposes of this application Figure 5 Sectional view of AA; Figure 7 For the purposes of this application Figure 6 BB section view; Figure 8 For the purposes of this application Figure 6 Enlarged view of part C; Figure 9 This is a schematic diagram of the preparation process of this application.

[0019] Explanation of the labels in the diagram: 1. Phosphogypsum storage silo; 2. Crushing and screening machine; 3. Impurity ion removal device; 4. Neutralization and conditioning tank; 5. Microbial culture tank; 6. Microbial liquid storage tank; 7. Nutrient solution preparation tank; 8. Twin-shaft mixer; 9. Organic matter addition device; 10. Mineral feeder; 11. Granulator; 12. Screening equipment; 13. Coating device; 14. Fermentation activation tank; 15. Aging silo; 16. Quality testing device; 17. Steam generator; 18. Air purification system; 19. Wastewater treatment device; 20. Automatic packaging machine; 301. Feed inlet; 302. Top cover; 303. Cation exchange column; 304. Anion exchange column; 305. Annular support plate; 306. Heating coil; 307. Vacuum evaporation ring; 308. Crystallizer; 309. Discharge port; 310. Outer shell; 311. Vacuum port; 312. Plate structure. Detailed Implementation

[0020] 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. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the protection scope of the present utility model.

[0021] Example 1: like Figures 1 to 9As shown, this embodiment provides a device for preparing phosphogypsum-based ecological restoration materials, including a raw material pretreatment system, a biological inoculation system, a compound modification system, a granulation and molding system, and a biological activation system. The raw material pretreatment system and the biological inoculation system are respectively connected to the compound modification system, and the compound modification system is sequentially connected to the granulation and molding system and the biological activation system. The raw material pretreatment system includes a phosphogypsum storage silo 1, a crushing and screening machine 2, an impurity ion removal device 3, and a neutralization and conditioning tank 4, which are connected in sequence.

[0022] The phosphogypsum storage silo 1 is a cylindrical structure with a diameter of 6-12m and an effective volume of 100-300m³. It has a 60° conical discharge port at the bottom, and a material level sensor monitors the material storage status. The top of the storage silo 1 has a dust removal port to prevent dust leakage, and the side walls have inspection doors and sampling ports for easy maintenance and quality control.

[0023] The crushing and screening machine 2 is located below the storage silo 1 and includes a combination structure of a jaw crusher and a vibrating screen. The jaw crusher has a feed opening size of 400×600mm and an output particle size adjustable from 0.1-5mm. The vibrating screen uses a double-layer screen with 5mm apertures in the upper layer and 2mm apertures in the lower layer, an amplitude of 6-8mm, and a frequency of 18-25Hz. The crushing and screening machine 2 crushes phosphogypsum to a particle size of 0.1-2mm, removes large particle impurities, and has a processing capacity of 5-15t / h.

[0024] The impurity ion removal device 3 is a cylindrical structure. Before use, the sieved phosphogypsum is washed with water, the solid phosphogypsum filter cake after washing is collected, water is added again and stirred to make it into a liquid slurry, and then the liquid phosphogypsum slurry is introduced into the impurity ion removal device 3. The impurity ion removal device 3 is provided with a feed inlet 301 at the upper end. The liquid phase phosphogypsum homogenate after water washing and resolubilization enters through the feed inlet 301. A cation exchange column 303 is fixedly connected to the bottom end of the feed inlet 301. A multi-layer plate structure 312 is fixedly connected to the inner wall of the cation exchange column 303. The multi-layer plate structure 312 is an alternating structure with gaps between the plates. The plate structure has gaps and is made of porous material. Both the plate structure 312 and the cation exchange column 303 are filled with iminodiacetic acid type chelating resin.

[0025] The multi-layered plate structure 312 divides the exchange column longitudinally into multiple relatively independent exchange zones, each layer being a separate exchange unit. When the phosphogypsum liquid flows from top to bottom, it passes through each plate zone sequentially, achieving a multi-stage series ion exchange process, equivalent to completing the effect of a multi-stage column series within a single column. The alternating gaps between the plates force the liquid to form a baffled flow path, extending the actual flow path. Each plate layer makes the liquid flow more uniformly distributed across the entire cross-section, improving resin utilization and thus enhancing the removal efficiency of impurity ions.

[0026] Both the plate structure 312 and the cation exchange column 303 are filled with iminodiacetic acid type resin. This resin contains the characteristic functional group: ―N(CH2COO⁻)2. This functional group has two carboxylic acid oxygen atoms and one nitrogen atom, which can provide at least three coordinating atoms to form stable five-membered ring chelates with metal ions. It has a high selective adsorption capacity. High-valence impurity ions with high charge density such as Fe³⁺, Al³⁺, Zn²⁺, Cd²⁺, and Ni²⁺ in phosphogypsum can preferentially undergo coordination reactions with the chelating groups on the resin surface to form stable cyclic complexes, thereby achieving efficient separation from the solution. Meanwhile, the main components such as Ca²⁺ and Mg²⁺ are retained due to their lower selectivity.

[0027] After the exchange, the liquid flows out from the bottom of the cation exchange column 303 under the action of gravity. An anion exchange column 304 is coaxially sleeved on the outside of the cation exchange column 303. There is a gap between the cation exchange column 303 and the anion exchange column 304, which can accommodate the outflowing liquid to gradually pass through the anion exchange column 304 for secondary exchange.

[0028] The anion exchange column 304 is made of porous material and filled with a strong-base anion exchange resin. Impurity ions in phosphogypsum (such as F⁻, PO₄³⁻, SO₄²⁻, AsO₄³⁻, CrO₄²⁻, Cl⁻, etc.) mainly exist in the slurry in anionic form. The strong-base anion exchange resin (such as quaternary ammonium type, -N⁺(CH₃)₃OH⁻) has high exchange capacity and broad selectivity. The resin immobilizes harmful anions on the resin surface through ion exchange, while simultaneously releasing OH⁻, without introducing new impurity cations. The anion exchange column 304, made of porous material, has high exchange efficiency. The porous material, acting as a column framework, provides a larger contact area and also functions as a micro-distributor, allowing the liquid to penetrate uniformly within the resin layer. The liquid after exchange with anion exchange resin 304 can further remove anionic impurity ions such as SO₄²⁻, PO₄³⁻, and F⁻. The iminodiacetic chelating resin packed in cation exchange column 303 and the strong base anion exchange resin packed in anion exchange column 304 should be replaced promptly after reaching saturation. Through the efficient exchange of cation exchange column 303 and anion exchange column 304, harmful cations and anions in phosphogypsum can be removed simultaneously, with the overall removal rate of impurity ions remaining stable at 85%-95%.

[0029] After passing through the anion exchange column 304, the liquid flows radially into the annular gap between the anion exchange column 304 and the annular support plate 305 coaxially sleeved on the outside. The top of the annular support plate 305 is located below the top of the anion exchange column 304. A heating ring 306 and a vacuum evaporation ring 307 are coaxially sleeved on the outside of the annular support plate 305. After the liquid stored in the annular gap reaches the top of the annular support plate 305, it gradually overflows along the inner wall of the vacuum evaporation ring 307. During this process, the heating ring 306 heats and concentrates the liquid through electric heating. A crystallizer 308 is fixedly connected to the bottom of the vacuum evaporation ring 307.

[0030] A vacuum evaporation ring 307 is coaxially fitted with an outer shell 310. The top of the outer shell 310 and the top of the anion exchange column 304 are both fixedly connected to a top cover 302. The outer wall of the cation exchange column 303 is fixedly connected to the inner wall of the top cover 302. At the same time, the bottom of the anion exchange column 304, the annular support plate 305, the vacuum evaporation ring 307, and the outer shell 310 are all fixedly connected to the crystallizer 308.

[0031] A vacuum evaporation chamber is formed between the top cover 302, the anion exchange column 304, the crystallizer 308, and the outer shell 310. A vacuum port 311 is provided on the top cover 302 and is connected to the vacuum evaporation chamber. A vacuum sensor is installed in the vacuum evaporation chamber to monitor the pressure inside the chamber. The pressure inside the evaporation chamber is maintained between -0.05 MPa and -0.09 MPa, which can lower the boiling point and reduce heating energy consumption. At the same time, a temperature sensor is provided to monitor the temperature inside the evaporation chamber and maintain it between 50℃ and 70℃. Within this vacuum and temperature range, the temperature can ensure the evaporation rate and is far below the boiling point at atmospheric pressure. Compared with evaporation at 100℃ at atmospheric pressure, lowering the boiling point to about 60℃ can save 25-35% of heating steam.

[0032] After being heated and concentrated, the liquid enters the crystallizer 308. The crystallizer 308 is equipped with a temperature control system. In the initial stage of the concentrated liquid flow, the temperature is adjusted to about 40-65 ℃ by the temperature control system, and then gradually cooled to about 30℃-42 ℃ to obtain large-particle crystals. A discharge port 309 is fixedly connected to the bottom of the crystallizer 308. After crystallization, the liquid is sent out through the discharge port 309.

[0033] The discharge port 309 is connected to the neutralization and equalization tank 4 via a pipeline. The neutralization and equalization tank 4 is a concrete structure with an effective volume of 20-50 m³. A mechanical stirrer is installed inside the tank, with a rotation speed of 30-60 rpm. Lime slurry or organic acid is added to adjust the pH of the phosphogypsum to 6.5-7.5, with a residence time of 1-2 hours. A sludge discharge port is located at the bottom of the tank for regular cleaning of sediment and impurities. A feed port and a testing port are located at the top of the tank for easy reagent addition and pH monitoring.

[0034] Example 2: like Figures 1 to 9 As shown in Example 1, this example provides a device for preparing phosphogypsum-based ecological restoration materials.

[0035] The biological inoculation system includes a nutrient solution preparation tank 7, a bacterial culture tank 5 and a bacterial solution storage tank connected in sequence; The microbial culture tank 5 includes a fermentation tank body, a stirring system, a ventilation system and a temperature control system. The stirring system is a paddle stirrer. The microbial liquid storage tank 6 is connected to the microbial culture tank 5 through a pipeline.

[0036] The microbial culture tank 5 is made of 316L stainless steel, with a volume of 1-5 m³, and is equipped with a heating jacket and insulation layer. An axial flow stirrer is installed inside the tank, with a speed of 50-200 rpm and an impeller diameter of 1 / 3 of the tank diameter. The ventilation system includes a sterile air compressor, filter, and flow meter, with an ventilation rate of 0.5 h⁻¹ – 2.0 h⁻¹. The temperature control system uses PID control, with a temperature control accuracy of ±0.5℃. The pH control system automatically adds acid and alkali solutions, with a pH control range of 6.5-7.5. Beneficial microorganisms such as rhizobia, phosphate bacteria, and silicate bacteria are cultured over a period of 24-72 hours, achieving a bacterial concentration of 2×10⁻⁶. 8 -10 9 CFU / mL or higher.

[0037] The bacterial culture storage tank has a volume of 500-2000 L, is made of 304 stainless steel, and is equipped with an insulation jacket and a stirring device. The storage temperature is 4-8 ℃, and a cooling system is provided to maintain the low temperature and prevent the decline of microbial activity. The tank is filled with nitrogen for protection against oxidation, and the storage period can reach 7-15 days.

[0038] Nutrient solution preparation tank 7 has a volume of 300-1000 L and is used to prepare nutrient solutions containing nitrogen, phosphorus, potassium, and trace elements. The main components include: urea 5-15 g / L, potassium dihydrogen phosphate 2-8 g / L, potassium sulfate 1-5 g / L, magnesium sulfate 0.5-2 g / L, ferrous sulfate 0.1-0.5 g / L, etc. The formula ratio is adjusted according to the requirements of different microbial strains.

[0039] The compound modification system includes a twin-shaft mixer 8, which is connected to the neutralization and conditioning tank 4 and the bacterial liquid storage tank 6 via pipelines. The twin-shaft mixer 8 includes a U-shaped mixing tank, a twin-shaft agitator, and multiple feeding ports. The twin-shaft agitator has two parallel shafts with ribbon blades. The feeding ports are located at the top of the tank. The compound modification system also includes an organic matter addition device 9 and a mineral feeder 10, both of which are connected to the twin-shaft mixer 8 via pipelines.

[0040] The twin-shaft mixer 8 includes a U-shaped tank, twin-shaft agitators, and a transmission system. The effective volume of the tank is 2-10 m³, with a length-to-width ratio of 2:1-3:1, and the inner wall is coated with PTFE for anti-adhesion. The twin-shaft agitator consists of two parallel shafts, with the shaft spacing being 1 / 3 of the tank width, equipped with ribbon-type blades, a rotation speed of 30-100 rpm, and a power of 15-45 kW. The top has 4-6 feeding ports for easy addition of different components, and the bottom has a gate-type discharge port with a discharge time of 2-5 minutes.

[0041] The organic matter addition device 9 includes a storage hopper, a screw feeder, and a weighing system. The storage hopper has a volume of 2-5 m³ and is used to store organic amendments such as humic acid, biochar, and straw powder. The screw feeder has a feeding accuracy of ±2%, and the addition amount is 5-15% of the mass of phosphogypsum. The weighing system uses an electronic belt scale to monitor the addition amount in real time to ensure accurate proportioning.

[0042] The mineral feeder 10 is equipped with an electronic weighing system, with a feeding accuracy of ±1%. It mainly adds essential mineral elements such as calcium salts (calcium chloride, calcium sulfate), magnesium salts (magnesium sulfate), and iron salts (ferrous sulfate). The amount added is determined based on soil test results, and is usually 2-8% of the mass of phosphogypsum.

[0043] The granulation system includes a granulator 11, a screening device 12, and a coating device 13 connected in sequence. The granulator 11 includes a granulation disc, a spray system, a baffle ring, and a dust collection device. The granulator 11 employs a disc granulation process. The granulation disc diameter is 1-3 m, the inclination angle is adjustable from 45-55°, and the rotation speed is 6-12 rpm. A baffle ring is installed around the disc, with an adjustable height of 50-200 mm, controlling the particle size to 2-8 mm. The spray system includes atomizing nozzles and a water pump, with a water pressure of 0.2-0.6 MPa and a granulation water consumption controlled at 8-15%. The dust collection device uses a bag filter to collect the dust generated during the granulation process, with a dust removal efficiency ≥99%.

[0044] The screening equipment 12 is a three-layer vibrating screen with screen specifications of 10 mm, 5 mm, and 2 mm, an amplitude of 4-8 mm, a frequency of 20-30 Hz, and a processing capacity of 3-10 t / h. Different particle sizes are obtained through grading: 2-5 mm fine particles are suitable for fine repairs; 5-8 mm medium particles are suitable for general repairs; and particles larger than 8 mm are returned to granulator 11 for regranulation.

[0045] The coating device 13 employs a fluidized bed coating process, using biodegradable materials such as polylactic acid and sodium alginate as coating materials, with a coating thickness of 50-200 μm. Coating process parameters include: inlet air temperature 50-70℃, spray pressure 0.15-0.3 MPa, and fluidizing velocity 1.5-3.0 m / s. The coated particles exhibit a slow-release function, with a nutrient release period of 6-12 months.

[0046] The biological activation system includes a fermentation activation tank 14, an aging chamber 15, and a quality detection device 16 connected in sequence.

[0047] The fermentation activation tank 14 includes a cylindrical tank body, a temperature control system, a humidity control system, and a ventilation system. The fermentation activation tank 14 is a cylindrical tank with a diameter of 1-2 m and a height of 2-4 m, made of stainless steel. The temperature control system maintains the fermentation temperature at 28-32 ℃, and the humidity control system maintains a relative humidity of 60-80%. The ventilation system provides a micro-aerobic environment with an aeration rate of 0.1 h⁻¹ – 0.5 h⁻¹. The fermentation time is 48-96 hours, activating the microbial activity in the material, awakening dormant bacteria, and enabling them to multiply rapidly.

[0048] The aging chamber 15 is a concrete structure with a volume of 50-200 m³, used for product maturation. Ventilation ducts are installed inside the chamber to maintain adequate ventilation and prevent anaerobic fermentation. During the aging period, the product is turned regularly to ensure uniform quality. The aging time is 7-15 days to allow the microbial community structure to stabilize.

[0049] The device also includes a steam generator 17, an air purification system 18, a wastewater treatment device 19, and an automatic packaging machine 20. The steam generator 17 is connected to the microbial culture tank 5 and the fermentation activation tank 14 via steam pipes.

[0050] The quality testing device 16 includes a microbial detector, a pH meter, and a nutrient analyzer. Microbial testing uses the plate count method to detect the number of viable bacteria and the composition of bacterial strains; the pH value detection range is 4-10, with an accuracy of ±0.1; nutrient analysis measures total nitrogen, available phosphorus, and available potassium, ensuring that product quality meets standard requirements.

[0051] Auxiliary equipment includes a steam generator 17, an air purification system 18, and a wastewater treatment device 19. The steam generator 17 is a vertical structure with a steam output of 500-2000 kg / h and an operating pressure of 0.8-1.0 MPa, providing steam for bacterial cultivation and equipment cleaning. The air purification system 18 includes an air compressor, a refrigerated dryer, and a precision filter, providing sterile air for biological cultivation. The wastewater treatment device 19 employs a biochemical treatment process to treat wastewater generated during production, ensuring that the effluent meets discharge standards.

[0052] The workflow is as follows: Phosphogypsum is crushed and screened from storage silo 1 by crusher and screener 2, then enters impurity ion removal device 3 to remove impurity ions, and then passes through neutralization and adjustment tank 4 to adjust the pH value. Simultaneously, beneficial microorganisms are cultivated in incubator 5, and the cultured bacterial solution is stored in incubator 6. The pretreated phosphogypsum is thoroughly mixed with the bacterial solution, organic matter, and minerals in twin-shaft mixer 8 to form a compound modified material. The compound material is granulated by granulator 11, graded by screening equipment 12, and then coated by coating device 13. The coated granules are activated for microbial activity in fermentation activation tank 14, matured in aging tank 15, and then tested for quality by quality inspection device 16. Finally, the finished product is packaged by automatic packaging machine 20.

[0053] The entire process achieves the harmless treatment and bio-activation modification of phosphogypsum, maintaining and monitoring microbial activity throughout. The resulting ecological restoration material possesses multiple functions, including soil improvement, nitrogen fixation, phosphorus solubilization, and antibacterial activity. The product has a viable microbial count ≥ 2 × 10⁻⁶. 8 -10 9 The CFU / g, pH value 6.5-7.5, organic matter content ≥15%, and effective nutrient content ≥8% all meet the technical requirements for ecological restoration materials.

[0054] This invention combines biological inoculation technology with physicochemical modification to transform phosphogypsum waste into functional ecological restoration materials. The entire system features advanced technology, a rational structure, and a high degree of automation, demonstrating promising industrial application prospects and environmental benefits.

[0055] In light of current practical needs, the above-described embodiments adopted in this application are not limited to these. Any changes made within the scope of knowledge possessed by those skilled in the art without departing from the concept of this application still fall within the protection scope of this utility model.

Claims

1. A device for preparing phosphogypsum-based ecological restoration materials, characterized in that: It includes a raw material pretreatment system, a biological inoculation system, a compound modification system, a granulation and molding system, and a biological activation system. The raw material pretreatment system and the biological inoculation system are respectively connected to the compound modification system, and the compound modification system, the granulation and molding system, and the biological activation system are connected in sequence. The raw material pretreatment system includes a phosphogypsum storage silo (1), a crushing and screening machine (2), an impurity ion removal device (3), and a neutralization and conditioning tank (4) connected in sequence. The impurity ion removal device (3) includes a feed inlet (301), a cation exchange column (303) is fixedly connected to the bottom end of the feed inlet (301), a top cover (302) is fixedly connected to the outer end of the cation exchange column (303), and an anion exchange column (304), an annular support plate (305), a heating ring (306), a vacuum evaporation ring (307), and an outer shell (310) are coaxially sleeved on the outside of the cation exchange column (303). There is a gap between the bottom end of the cation exchange column (303) and the bottom end of the anion exchange column (304), and there are annular gaps between adjacent cation exchange columns (303), anion exchange columns (304), and annular support plates (305); The top of the annular support plate (305) is located below the top of the anion exchange column (304); The vacuum evaporation ring (307) has a hollow cylindrical structure. A crystallizer (308) is fixedly connected to the bottom end of the vacuum evaporation ring (307), and a discharge port (309) is fixedly connected to the bottom end of the crystallizer (308). The top ends of the anion exchange column (304) and the outer shell (310) are fixedly connected to the bottom end of the top cover (302), and the bottom ends of the anion exchange column (304), the annular support plate (305), the vacuum evaporation ring (307), and the outer shell (310) are fixedly connected to the crystallizer (308). A vacuum evaporation chamber is formed between the top cover (302), the anion exchange column (304), the crystallizer (308), and the outer shell (310); The top cover (302) is provided with a vacuum port (311), which is connected to the vacuum evaporation chamber; The biological inoculation system includes a nutrient solution preparation tank (7), a bacterial culture tank (5) and a bacterial solution storage tank (6) connected in sequence; The compound modification system includes a biaxial mixer (8), which is connected to the neutralization and conditioning tank (4) and the bacterial liquid storage tank (6) through pipelines; The granulation system includes a granulator (11), a screening device (12), and a coating device (13) connected in sequence; The bio-activation system includes a fermentation activation tank (14), an aging chamber (15), and a quality testing device (16) connected in sequence.

2. The apparatus for preparing phosphogypsum-based ecological restoration materials according to claim 1, characterized in that: The cation exchange column (303) is a hollow cylindrical structure. A multi-layer plate structure (312) is fixedly connected to the inner wall of the cation exchange column (303). The multi-layer plate structure (312) is an alternating structure with gaps between the plates. The plate structure (312) has notches. The plate structure (312) is made of porous material. Both the plate structure (312) and the cation exchange column (303) are filled with cation exchange resin.

3. The apparatus for preparing phosphogypsum-based ecological restoration materials according to claim 1, characterized in that: The anion exchange column (304) is made of porous material and is filled with anion exchange resin.

4. The apparatus for preparing phosphogypsum-based ecological restoration materials according to claim 1, characterized in that: The phosphogypsum storage silo (1) has a cylindrical structure with a conical discharge port at the bottom.

5. The apparatus for preparing phosphogypsum-based ecological restoration materials according to claim 1, characterized in that: The microbial culture tank (5) includes a fermentation tank body, a stirring system, a ventilation system and a temperature control system. The stirring system is a paddle stirrer. The microbial liquid storage tank (6) is connected to the microbial culture tank (5) through a pipeline.

6. The apparatus for preparing phosphogypsum-based ecological restoration materials according to claim 1, characterized in that: The twin-shaft mixer (8) includes a U-shaped mixing tank, a twin-shaft agitator and multiple feeding ports. The twin-shaft agitator consists of two parallel shafts with ribbon blades. The feeding ports are located at the top of the tank. The compound modification system also includes an organic matter addition device (9) and a mineral feeder (10), both of which are connected to the twin-shaft mixer (8) via pipelines.

7. The apparatus for preparing phosphogypsum-based ecological restoration materials according to claim 1, characterized in that: The granulator (11) includes a granulation disc, a spray system, a baffle ring, and a dust removal device.

8. The apparatus for preparing phosphogypsum-based ecological restoration materials according to claim 1, characterized in that: The fermentation activation tank (14) includes a cylindrical tank body, a temperature control system, a humidity control system, and a ventilation system.

9. The apparatus for preparing phosphogypsum-based ecological restoration materials according to claim 1, characterized in that: The device also includes a steam generator (17), an air purification system (18), a wastewater treatment device (19), and an automatic packaging machine (20). The steam generator (17) is connected to the microbial culture tank (5) and the fermentation activation tank (14) through a steam pipe.

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