Advanced treatment method of tungsten beneficiation wastewater

Abstract

The invention discloses an advanced treatment method of tungsten beneficiation wastewater, which is characterized in that a composite flocculant is adopted to flocculate the tungsten beneficiation wastewater, and the composite flocculant is mainly composed of cationic polyacrylamide, a flocculant A and lignocellulose, the flocculant A comprises at least one of polyferric sulfate, polyaluminum chloride, polyaluminum ferric chloride, polyaluminum ferric sulfate, ferric sulfate, ferrous sulfate and aluminum chloride. According to the advanced treatment method for the tungsten beneficiation wastewater, under the action of the composite flocculant, the cost of a treatment agent can be reduced to about 0.16-0.20 yuan / m < 3 >, the cost reduction amplitude is as high as 80% or above, the treatment time can be shortened to be within 10 min, the precipitation time is greatly shortened, meanwhile, suspended solids in the wastewater can be effectively removed, actual production requirements are met, and the method is suitable for industrial production. The method has the advantages of low treatment cost, high treatment efficiency, good removal effect, good adaptability and the like, can realize advanced treatment of the tungsten beneficiation wastewater, and is high in use value and good in application prospect.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology and relates to a method for the deep treatment of tungsten ore beneficiation wastewater. Background Technology

[0002] Tungsten ore beneficiation processes generate large amounts of wastewater, typically containing various pollutants such as water glass, suspended solids, and COD / ammonia nitrogen. Water glass is commonly used as a mineral depressant in tungsten flotation and also disperses the slurry. After flotation, residual water glass in the wastewater adsorbs onto the surface of fine particles, causing them to become negatively charged. This repulsion between particles creates a stable dispersion system, making it extremely difficult for suspended solids to settle. Direct reuse of tungsten beneficiation wastewater with high concentrations of suspended solids in the flotation process would result in sludge covering the surface of valuable minerals, hindering their flotation. Furthermore, the sludge would consume significant amounts of flotation additives, impacting flotation performance and increasing costs. Additionally, high levels of suspended solids also preclude direct discharge. Therefore, effectively removing suspended solids from tungsten beneficiation wastewater is crucial for its treatment and disposal.

[0003] To address the aforementioned problems with tungsten ore beneficiation wastewater, a method for reusing scheelite ore beneficiation wastewater has been proposed in the prior art. This involves first adjusting the pH of the wastewater to 7-8, then sequentially adding polyaluminum chloride and polyacrylamide, mixing thoroughly, and aging to obtain a clarified recovered liquid. However, the above-mentioned reuse method still has the following shortcomings: (1) Poor adaptability to wastewater, high reagent costs, and high operating costs. In the above methods, the pH of the wastewater needs to be adjusted to 7-8 before adding flocculant. The requirements for influent water quality are strict, and pH needs to be precisely controlled, which increases lime / acid consumption and equipment operating costs.

[0004] (2) Low processing efficiency and long processing cycle. In the above method, the aging time is 40~90 min, which leads to a long processing cycle and low processing efficiency, which is not conducive to improving economic benefits.

[0005] (3) High reagent dosage leads to high treatment costs. In the above methods, the dosage of polyaluminum chloride added is 700~900 g / m³. 3 The amount of polyacrylamide added is 3~9 g / m³. 3 According to the prices recorded in the above method, polyaluminum chloride is 1.2 yuan / kg and polyacrylamide is 16 yuan / kg, and the calculated cost is 0.888~1.224 yuan / cubic meter.

[0006] For the reasons stated above, this invention is proposed. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a deep treatment method for tungsten ore beneficiation wastewater that has low treatment cost, high treatment efficiency, good removal effect and good adaptability.

[0008] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A method for deep treatment of tungsten ore beneficiation wastewater involves using a composite flocculant to treat the wastewater through flocculation. The composite flocculant is mainly composed of cationic polyacrylamide, flocculant A, and lignocellulose. The flocculant A includes at least one of polyferric sulfate, polyaluminum chloride, polyaluminum ferric chloride, polyaluminum ferric sulfate, ferric sulfate, ferrous sulfate, and aluminum chloride.

[0009] In a further improvement of the above-mentioned deep treatment method, the mass ratio of cationic polyacrylamide, flocculant A, and lignocellulose is 5-8:1-3:1-5.

[0010] In a further improvement to the aforementioned deep processing method, the cationic polyacrylamide has a molecular weight of 8 million to 12 million.

[0011] The above-mentioned advanced treatment method is further improved by using a composite flocculant to treat tungsten ore beneficiation wastewater through flocculation, including the following treatments: S1. Adjust the pH of the tungsten ore beneficiation wastewater to 6-9; S2. Add composite flocculant to tungsten ore beneficiation wastewater, stir, let stand, and complete the deep treatment of tungsten ore beneficiation wastewater.

[0012] In a further improvement to the above-mentioned deep treatment method, in step S2, the composite flocculant is added to the tungsten beneficiation wastewater in the form of a composite flocculant solution; the volume ratio of the composite flocculant solution to the tungsten beneficiation wastewater is 1 to 5:125.

[0013] In a further improvement to the above-mentioned deep treatment method, the concentration of the composite flocculant in the composite flocculant solution is 0.5 g / L to 3 g / L.

[0014] In a further improvement to the above-mentioned deep treatment method, the composite flocculant solution is prepared by the following method: cationic polyacrylamide, flocculant A and lignocellulose are mixed, stirred for 1 hour, and water is added to obtain the composite flocculant solution.

[0015] In a further improvement to the above-mentioned deep processing method, in step S2, the stirring time is 1 min to 2 min; and the settling time is 5 min to 10 min.

[0016] In a further improvement to the above-mentioned deep treatment method, in step S1, lime slurry is added to the tungsten beneficiation wastewater and stirred for 5 to 10 minutes to adjust the pH value of the tungsten beneficiation wastewater to 6 to 9.

[0017] In a further improvement to the above-mentioned deep treatment method, in step S1, the suspended solids content in the tungsten ore beneficiation wastewater is 625 ppm to 1200 ppm.

[0018] Compared with the prior art, the advantages of the present invention are as follows: To address the shortcomings of existing composite flocculants, such as slow settling speed, poor flocculation effect, poor stability, and poor adaptability, as well as the resulting high reagent dosage, high treatment cost, and low treatment efficiency, this invention creatively proposes a method for the deep treatment of tungsten ore beneficiation wastewater. This method employs a composite flocculant to treat the tungsten ore beneficiation wastewater. The composite flocculant mainly consists of cationic polyacrylamide, flocculant A, and lignocellulose. Flocculant A includes at least one of polyferric sulfate, polyaluminum chloride, polyaluminum ferric chloride, polyaluminum ferric sulfate, ferric sulfate, ferrous sulfate, and aluminum chloride. Compared with conventional flocculants, the cationic polyacrylamide in this invention utilizes its cationic groups on its molecular chain to adsorb negatively charged suspended particles, colloids, and some dissolved organic matter in the wastewater through electrostatic interactions, thus neutralizing the charge. Simultaneously, its long-chain structure can bridge multiple micro-flocs, promoting floc coarsening and increasing settling speed. Flocculant A primarily works by hydrolyzing to generate polynuclear hydroxyl complexes, compressing the colloidal double layer, disrupting colloidal stability, and destabilizing and coagulating fine particles. Simultaneously, the generated metal hydroxide precipitates can trap and sweep away impurities in wastewater, enhancing solid-liquid separation. Lignocellulose, as a natural organic polymer, is rich in active groups such as hydroxyl groups on its surface, which can adsorb heavy metal ions and organic matter in wastewater. Its fibrous network structure enhances the mechanical strength and toughness of flocs, preventing floc breakage, improving floc structure, and increasing floc density and settling properties. Furthermore, the combined action of cationic polyacrylamide, flocculant A, and lignocellulose forms a stable structure with specific flocculation functional groups, resulting in the following unexpected technical effects: (1.1) Synergistic effect: Flocculant A first destabilizes the colloid to form micro flocs, cationic polyacrylamide amplifies the size of the flocs through bridging and charge neutralization, and lignocellulose embeds itself into the floc network to enhance its stability. The three form a synergistic mechanism of "destabilization-bridging-reinforcement".

[0019] (1.2) Structural optimization: The fibrous skeleton of lignocellulose is combined with the flexible long chain of cationic polyacrylamide to form a three-dimensional network floc structure that combines rigidity and flexibility, thereby improving the floc settling speed and shear resistance.

[0020] (1.3) Complementary functions: cationic polyacrylamide focuses on adsorption bridging, flocculant A focuses on charge neutralization and sweeping, and lignocellulose focuses on structural reinforcement and heavy metal adsorption, covering multiple needs of the flocculation process.

[0021] Furthermore, the composite flocculant of the present invention alters the reaction pathway for pollutant removal through multi-component synergy, and the reaction mechanism involved is as follows: (2.1) Directional adsorption and targeted destabilization: The hydrolysis products of flocculant A preferentially combine with high-valence metal ions (such as tungstate) in wastewater to form precipitation nuclei; the cationic groups of cationic polyacrylamide target and adsorb negatively charged silicate colloids and organic impurities to achieve selective destabilization.

[0022] (2.2) Gradient flocculation and network formation: The destabilized microparticles aggregate step by step under the bridging of cationic polyacrylamide. During this process, lignocellulose is interspersed among them, and the flocs are reinforced by hydrogen bonds and van der Waals forces to form a dense floc network with lignocellulose as the skeleton and inorganic-organic complex filling.

[0023] (2.3) Synergistic effect of characteristic functional groups: The hydroxyl groups of lignocellulose, the hydroxyl complex of flocculant A, the amide group of cationic polyacrylamide and the cationic group form a multifunctional group system, which can simultaneously capture different pollutants through coordination, hydrogen bonding and electrostatic interaction.

[0024] (2.4) Innovative reaction pathway: Traditional flocculation pathways are mostly “disordered aggregation – random sedimentation”, while the composite flocculant of this invention forms a directional reaction of “directional destabilization – step bridging – skeleton reinforcement”.

[0025] Therefore, when the composite flocculant of this invention is used to treat tungsten ore beneficiation wastewater, it exhibits a highly efficient flocculation effect of "one-step addition and synergistic multiple effects", which fundamentally changes the action mechanism and reaction path of the agent and pollutants. Thus, tungsten ore beneficiation wastewater can be treated efficiently with a low dosage of flocculant.

[0026] Therefore, the advanced treatment method for tungsten ore beneficiation wastewater of this invention, under the action of composite flocculant, can reduce the cost of wastewater treatment agents from approximately RMB 0.89~1.22 / cubic meter to approximately RMB 0.16~0.20 / cubic meter, a cost reduction of over 80%, achieving a leap in technical and economic benefits. Simultaneously, it can shorten the wastewater treatment time to less than 10 minutes, significantly reducing sedimentation time and achieving a leap in treatment efficiency. This results in an order-of-magnitude improvement in both treatment efficiency and economic benefits. Furthermore, it effectively removes suspended solids from the wastewater; after treatment by this method, the suspended solids index in the wastewater is reduced to 30 mg / L, stably meeting the requirements of "GB 25467-2010 Emission Standard of Pollutants for Copper, Nickel and Cobalt Industries," which aligns with actual production needs. It possesses advantages such as low treatment cost, high treatment efficiency, good removal effect, and good adaptability, enabling advanced treatment of tungsten ore beneficiation wastewater, demonstrating high use value and promising application prospects. Detailed Implementation

[0027] The present invention will be further described below with reference to specific preferred embodiments, but this does not limit the scope of protection of the present invention.

[0028] Example 1 A method for deep treatment of tungsten ore beneficiation wastewater specifically involves using a composite flocculant to treat the tungsten ore beneficiation wastewater. The composite flocculant is composed of cationic polyacrylamide, flocculant A, and lignocellulose, and flocculant A is polyaluminum chloride.

[0029] In this invention, the lignocellulose used is mainly derived from wood and is a composite of natural cellulose, hemicellulose, and lignin. Lignin contains abundant functional groups such as phenylpropane structures, phenolic hydroxyl groups, and methoxy groups, giving it stronger hydrophobicity and adsorption capacity for heavy metal ions and organic matter (through π-π interactions, complexation, etc.), which is clearly not present in pure cellulose. Meanwhile, the hemicellulose in the lignocellulose used has more branches and hydrophilic groups (such as carboxyl groups), which improves hydrophilicity and dispersibility. Natural fibers have a coarse, porous structure and a large specific surface area, resulting in stronger physical entanglement and bridging capabilities. Therefore, lignocellulose in this system is not only the "physical framework" but also a multifunctional component with adsorption, complexation, hydrophobic aggregation, and network enhancement capabilities. Other celluloses, such as natural plant cellulose and nanocellulose, have relatively simple structures and lack synergistic effects. For example, carboxymethyl cellulose undergoes an electron neutralization reaction with cationic polyacrylamide, causing both to become ineffective; clearly, it cannot replace "lignocellulose."

[0030] In this embodiment, the mass ratio of cationic polyacrylamide, flocculant A, and lignocellulose used is 5:1:4.

[0031] In this embodiment, the cationic polyacrylamide used has a viscosity-average molecular weight of 8 million to 9 million.

[0032] In this embodiment, a composite flocculant is used to treat tungsten ore beneficiation wastewater through flocculation, including the following treatment: S1. Measure 1000 mL of tungsten ore beneficiation wastewater and pour it into a beaker. Add lime slurry and stir for 10 min to adjust the pH of the tungsten ore beneficiation wastewater to 7-8.

[0033] S2. Add composite flocculant to the tungsten ore beneficiation wastewater after adjusting the pH value in step S1, stir for 2 minutes, let stand for 10 minutes to allow the flocculants to precipitate, and obtain supernatant and bottom slag to complete the deep treatment of tungsten ore beneficiation wastewater.

[0034] In step S2, the composite flocculant is added to the tungsten beneficiation wastewater in the form of a composite flocculant solution, wherein the volume ratio of the composite flocculant solution to the tungsten beneficiation wastewater is 1:25.

[0035] In this embodiment, the concentration of the composite flocculant in the composite flocculant solution is 0.5 g / L.

[0036] In this embodiment, the composite flocculant solution was prepared by the following method: cationic polyacrylamide, polyaluminum chloride and lignocellulose were mixed in a mixer, stirred for 1 h, and water was added to obtain the composite flocculant solution.

[0037] In this embodiment, the water quality analysis results of the supernatant are shown in Table 1.

[0038] Table 1. Results of deep sedimentation experiments on tungsten ore beneficiation wastewater in Example 1

[0039] Remark:" L "" indicates that the detection result is below the method detection limit.

[0040] Example 2 A method for deep treatment of tungsten ore beneficiation wastewater specifically involves using a composite flocculant to treat the tungsten ore beneficiation wastewater. The composite flocculant is composed of cationic polyacrylamide, flocculant A, and lignocellulose, and flocculant A is polyaluminum chloride.

[0041] In this embodiment, the mass ratio of cationic polyacrylamide, flocculant A, and lignocellulose used is 5:4:1.

[0042] In this embodiment, the cationic polyacrylamide used has a viscosity-average molecular weight of 8 million to 9 million.

[0043] In this embodiment, a composite flocculant is used to treat tungsten ore beneficiation wastewater through flocculation, including the following treatment: S1. Measure 1000 mL of tungsten ore beneficiation wastewater and pour it into a beaker. Add lime slurry and stir for 10 min to adjust the pH of the tungsten ore beneficiation wastewater to 7-8.

[0044] S2. Add composite flocculant to the tungsten ore beneficiation wastewater after adjusting the pH value in step S1, stir for 2 minutes, let stand for 10 minutes to allow the flocculants to precipitate, and obtain supernatant and bottom slag to complete the deep treatment of tungsten ore beneficiation wastewater.

[0045] In step S2, the composite flocculant is added to the tungsten beneficiation wastewater in the form of a composite flocculant solution, wherein the volume ratio of the composite flocculant solution to the tungsten beneficiation wastewater is 1:25.

[0046] In this embodiment, the concentration of the composite flocculant in the composite flocculant solution is 0.5 g / L.

[0047] In this embodiment, the composite flocculant solution was prepared by the following method: cationic polyacrylamide, polyaluminum chloride and lignocellulose were mixed in a mixer, stirred for 1 h, and water was added to obtain the composite flocculant solution.

[0048] In this embodiment, the water quality analysis results of the supernatant are shown in Table 2.

[0049] Table 2. Results of deep sedimentation experiments on tungsten ore beneficiation wastewater in Example 2

[0050] Remark:" L "" indicates that the detection result is below the method detection limit.

[0051] Example 3 A method for deep treatment of tungsten ore beneficiation wastewater specifically involves using a composite flocculant to treat the tungsten ore beneficiation wastewater. The composite flocculant is composed of cationic polyacrylamide, flocculant A, and lignocellulose, and flocculant A is polyaluminum chloride.

[0052] In this embodiment, the mass ratio of cationic polyacrylamide, flocculant A, and lignocellulose used is 8:1:1.

[0053] In this embodiment, the cationic polyacrylamide used has a viscosity-average molecular weight of 8 million to 9 million.

[0054] In this embodiment, a composite flocculant is used to treat tungsten ore beneficiation wastewater through flocculation, including the following treatment: S1. Measure 1000 mL of tungsten ore beneficiation wastewater and pour it into a beaker. Add lime slurry and stir for 10 min to adjust the pH of the tungsten ore beneficiation wastewater to 7-8.

[0055] S2. Add composite flocculant to the tungsten ore beneficiation wastewater after adjusting the pH value in step S1, stir for 2 minutes, let stand for 10 minutes to allow the flocculants to precipitate, and obtain supernatant and bottom slag to complete the deep treatment of tungsten ore beneficiation wastewater.

[0056] In step S2, the composite flocculant is added to the tungsten beneficiation wastewater in the form of a composite flocculant solution, wherein the volume ratio of the composite flocculant solution to the tungsten beneficiation wastewater is 1:25.

[0057] In this embodiment, the concentration of the composite flocculant in the composite flocculant solution is 0.5 g / L.

[0058] In this embodiment, the composite flocculant solution was prepared by the following method: cationic polyacrylamide, polyaluminum chloride and lignocellulose were mixed in a mixer, stirred for 1 h, and water was added to obtain the composite flocculant solution.

[0059] In this embodiment, the water quality analysis results of the supernatant are shown in Table 3.

[0060] Table 3. Results of deep sedimentation experiments on tungsten ore beneficiation wastewater in Example 3

[0061] Remark:" L "" indicates that the detection result is below the method detection limit.

[0062] Example 4 A method for deep treatment of tungsten ore beneficiation wastewater specifically involves using a composite flocculant to treat the tungsten ore beneficiation wastewater. The composite flocculant is composed of cationic polyacrylamide, flocculant A, and lignocellulose, and flocculant A is polyaluminum chloride.

[0063] In this embodiment, the mass ratio of cationic polyacrylamide, flocculant A, and lignocellulose used is 6:1:3.

[0064] In this embodiment, the cationic polyacrylamide used has a viscosity-average molecular weight of 8 million to 9 million.

[0065] In this embodiment, a composite flocculant is used to treat tungsten ore beneficiation wastewater through flocculation, including the following treatment: S1. Measure 1000 mL of tungsten ore beneficiation wastewater and pour it into a beaker. Add lime slurry and stir for 10 min to adjust the pH of the tungsten ore beneficiation wastewater to 7-8.

[0066] S2. Add composite flocculant to the tungsten ore beneficiation wastewater after adjusting the pH value in step S1, stir for 2 minutes, let stand for 10 minutes to allow the flocculants to precipitate, and obtain supernatant and bottom slag to complete the deep treatment of tungsten ore beneficiation wastewater.

[0067] In step S2, the composite flocculant is added to the tungsten beneficiation wastewater in the form of a composite flocculant solution, wherein the volume ratio of the composite flocculant solution to the tungsten beneficiation wastewater is 1:25.

[0068] In this embodiment, the concentration of the composite flocculant in the composite flocculant solution is 0.5 g / L.

[0069] In this embodiment, the composite flocculant solution was prepared by the following method: cationic polyacrylamide, polyaluminum chloride and lignocellulose were mixed in a mixer, stirred for 1 h, and water was added to obtain the composite flocculant solution.

[0070] In this embodiment, the water quality analysis results of the supernatant are shown in Table 4.

[0071] Table 4. Results of deep sedimentation experiments on tungsten ore beneficiation wastewater in Example 4

[0072] Remark:" L "" indicates that the detection result is below the method detection limit.

[0073] Based on the experimental results of the four embodiments above, it is evident that using a composite flocculant composed of cationic polyacrylamide, polyaluminum chloride, and lignocellulose to treat tungsten ore beneficiation wastewater, and adding it after adjusting the pH to 7-8, yields excellent treatment results. The mass ratio of the components is a key factor affecting the suspended solids (SS) removal rate. The optimal ratio of 6:1:3 (CPAM:PAC:lignocellulose) achieves the best results, with an SS removal rate as high as 96.9%, and an effluent concentration (36 mg / L) significantly better than the national standard. Imbalance in the ratio leads to a significant decrease in SS removal efficiency. The experiments demonstrate that a suitable ternary compound can achieve efficient and low-cost advanced treatment.

[0074] Example 5 A method for deep treatment of tungsten ore beneficiation wastewater specifically involves using a composite flocculant to treat the tungsten ore beneficiation wastewater. The composite flocculant is composed of cationic polyacrylamide, flocculant A, and lignocellulose, and flocculant A is polyaluminum chloride.

[0075] In this embodiment, the mass ratio of cationic polyacrylamide, flocculant A, and lignocellulose used is 6:1:3.

[0076] In this embodiment, the cationic polyacrylamide used has a viscosity-average molecular weight of 9 million to 10 million.

[0077] In this embodiment, a composite flocculant is used to treat tungsten ore beneficiation wastewater through flocculation, including the following treatment: S1. Measure 1000 mL of tungsten ore beneficiation wastewater and pour it into a beaker. Add lime slurry and stir for 10 min to adjust the pH of the tungsten ore beneficiation wastewater to 7-8.

[0078] S2. Add composite flocculant to the tungsten ore beneficiation wastewater after adjusting the pH value in step S1, stir for 2 minutes, let stand for 10 minutes to allow the flocculants to precipitate, and obtain supernatant and bottom slag to complete the deep treatment of tungsten ore beneficiation wastewater.

[0079] In step S2, the composite flocculant is added to the tungsten beneficiation wastewater in the form of a composite flocculant solution, wherein the volume ratio of the composite flocculant solution to the tungsten beneficiation wastewater is 1:25.

[0080] In this embodiment, the concentration of the composite flocculant in the composite flocculant solution is 0.5 g / L.

[0081] In this embodiment, the composite flocculant solution was prepared by the following method: cationic polyacrylamide, polyaluminum chloride and lignocellulose were mixed in a mixer, stirred for 1 h, and water was added to obtain the composite flocculant solution.

[0082] In this embodiment, the water quality analysis results of the supernatant are shown in Table 5.

[0083] Table 5. Results of deep sedimentation experiments on tungsten ore beneficiation wastewater in Example 5

[0084] Remark:" L "" indicates that the detection result is below the method detection limit.

[0085] Example 6 A method for deep treatment of tungsten ore beneficiation wastewater specifically involves using a composite flocculant to treat the tungsten ore beneficiation wastewater. The composite flocculant is composed of cationic polyacrylamide, flocculant A, and lignocellulose, and flocculant A is polyaluminum chloride.

[0086] In this embodiment, the mass ratio of cationic polyacrylamide, flocculant A, and lignocellulose used is 6:1:3.

[0087] In this embodiment, the cationic polyacrylamide used has a viscosity-average molecular weight of 10 million to 12 million.

[0088] In this embodiment, a composite flocculant is used to treat tungsten ore beneficiation wastewater through flocculation, including the following treatment: S1. Measure 1000 mL of tungsten ore beneficiation wastewater and pour it into a beaker. Add lime slurry and stir for 10 min to adjust the pH of the tungsten ore beneficiation wastewater to 7-8.

[0089] S2. Add composite flocculant to the tungsten ore beneficiation wastewater after adjusting the pH value in step S1, stir for 2 minutes, let stand for 10 minutes to allow the flocculants to precipitate, and obtain supernatant and bottom slag to complete the deep treatment of tungsten ore beneficiation wastewater.

[0090] In step S2, the composite flocculant is added to the tungsten beneficiation wastewater in the form of a composite flocculant solution, wherein the volume ratio of the composite flocculant solution to the tungsten beneficiation wastewater is 1:25.

[0091] In this embodiment, the concentration of the composite flocculant in the composite flocculant solution is 0.5 g / L.

[0092] In this embodiment, the composite flocculant solution was prepared by the following method: cationic polyacrylamide, polyaluminum chloride and lignocellulose were mixed in a mixer, stirred for 1 h, and water was added to obtain the composite flocculant solution.

[0093] In this embodiment, the water quality analysis results of the supernatant are shown in Table 6.

[0094] Table 6. Results of deep sedimentation experiments on tungsten ore beneficiation wastewater in Example 6

[0095] Remark:" L "" indicates that the detection result is below the method detection limit.

[0096] In this embodiment, the effect of the molecular weight of cationic polyacrylamide (CPAM) on the treatment effect was investigated under a fixed optimal ratio (CPAM:PAC:lignocellulose = 6:1:3). The results showed that suspended solids were effectively removed within a molecular weight range of 8 million to 12 million, with effluent concentrations (36–52 mg / L) meeting national standards. The effect was slightly better at a molecular weight of 8 million to 9 million (36 mg / L), but the differences compared to 9 million to 10 million (52 mg / L) and 10 million to 12 million (44 mg / L) were within acceptable ranges. This indicates that, under the determined optimal ratio, the CPAM molecular weight can guarantee treatment effectiveness across a wide range, and the process has good versatility.

[0097] Comparative Example 1 A method for deep treatment of tungsten ore beneficiation wastewater is basically the same as that in Example 3. In Comparative Example 1, the composite flocculant used is composed of cationic polyacrylamide and flocculant A (polyferric sulfate), wherein the mass ratio of cationic polyacrylamide to polyferric sulfate is 4:1.

[0098] The water quality analysis results of the supernatant in Comparative Example 1 are shown in Table 7.

[0099] Table 7. Results of deep sedimentation experiments on tungsten ore beneficiation wastewater in Comparative Example 1

[0100] Remark:" L "" indicates that the detection result is below the method detection limit.

[0101] According to the test results of Comparative Example 1, when only cationic polyacrylamide and polyaluminum chloride (ratio 4:1) were used in the composite flocculant, and the lignocellulose component was completely omitted, the treatment effect decreased significantly. The concentration of suspended solids in the treated wastewater was 90 mg / L, which is higher than the national emission standard of 80 mg / L. Combining the experimental results in Example 3 and Comparative Example 1, lignocellulose plays a key role in the ternary composite flocculant system. Its fibrous network structure can effectively enhance floc strength and settling performance. The absence of this component will weaken the overall synergistic effect of the system, resulting in the suspended solids removal effect failing to consistently reach the optimal standard.

[0102] The results above show that, compared with conventional treatment methods, the advanced treatment method for tungsten ore beneficiation wastewater of this invention, under the action of composite flocculants, can reduce the cost of wastewater treatment agents from approximately RMB 0.89~1.22 / cubic meter to approximately RMB 0.16~0.20 / cubic meter, a cost reduction of over 80%, achieving a leap in technical and economic benefits. Simultaneously, it can shorten the wastewater treatment time to less than 10 minutes, significantly reducing sedimentation time and achieving a leap in treatment efficiency. This results in an order-of-magnitude improvement in both treatment efficiency and economic benefits. Furthermore, it effectively removes suspended solids from the wastewater; after treatment by this method, the suspended solids index in the wastewater is reduced to 30 mg / L, stably meeting the requirements of "GB 25467-2010 Emission Standard of Pollutants for Copper, Nickel and Cobalt Industries," which aligns with actual production needs. This method has advantages such as low treatment cost, high treatment efficiency, good removal effect, and good adaptability, enabling advanced treatment of tungsten ore beneficiation wastewater. It has high practical value and promising application prospects.

[0103] The above embodiments are merely preferred embodiments of the present invention, and the scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for deep treatment of tungsten ore beneficiation wastewater, characterized in that, A composite flocculant is used to treat tungsten ore beneficiation wastewater; the composite flocculant is mainly composed of cationic polyacrylamide, flocculant A and lignocellulose; the flocculant A includes at least one of polyferric sulfate, polyaluminum chloride, polyaluminum ferric chloride, polyaluminum ferric sulfate, ferric sulfate, ferrous sulfate and aluminum chloride.

2. The depth processing method according to claim 1, characterized in that, The mass ratio of the cationic polyacrylamide, flocculant A, and lignocellulose is 5-8:1-3:1-5.

3. The depth processing method according to claim 2, characterized in that, The cationic polyacrylamide has a viscosity-average molecular weight of 8 million to 12 million.

4. The depth processing method according to any one of claims 1 to 3, characterized in that, The flocculation treatment of tungsten ore beneficiation wastewater using composite flocculants includes the following treatments: S1. Adjust the pH of the tungsten ore beneficiation wastewater to 6-9; S2. Add composite flocculant to tungsten ore beneficiation wastewater, stir, let stand, and complete the deep treatment of tungsten ore beneficiation wastewater.

5. The depth processing method according to claim 4, characterized in that, In step S2, the composite flocculant is added to the tungsten ore beneficiation wastewater in the form of a composite flocculant solution; the volume ratio of the composite flocculant solution to the tungsten ore beneficiation wastewater is 1 to 5:

125.

6. The depth processing method according to claim 5, characterized in that, The concentration of the composite flocculant in the composite flocculant solution is 0.5 g / L to 3 g / L.

7. The depth processing method according to claim 6, characterized in that, The composite flocculant solution is prepared by the following method: cationic polyacrylamide, flocculant A and lignocellulose are mixed, stirred for 1 h, and water is added to obtain the composite flocculant solution.

8. The depth processing method according to claim 4, characterized in that, In step S2, the stirring time is 1 min to 2 min; the settling time is 5 min to 10 min.

9. The depth processing method according to claim 4, characterized in that, In step S1, lime slurry is added to tungsten ore beneficiation wastewater and stirred for 5 to 10 minutes to adjust the pH of the tungsten ore beneficiation wastewater to 6 to 9.

10. The depth processing method according to claim 9, characterized in that, In step S1, the suspended solids content in the tungsten ore beneficiation wastewater is 625 ppm to 1200 ppm.

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