Acid-base regeneration device for tungsten smelting high-salinity wastewater

Abstract

The utility model discloses an acid-base regeneration device for tungsten smelting high-salinity wastewater, which comprises a softening unit provided with a plurality of water treatment chemicals; the nanofiltration unit is connected to the softening unit and is used for removing sulfate radicals in the wastewater; the reverse osmosis unit is connected to the nanofiltration unit, and the first output end of the reverse osmosis unit is connected to the fresh water storage mechanism; the bipolar membrane electrodialysis unit is connected to the second output end of the reverse osmosis unit through a pump body, and is provided with an acid liquor outlet and an alkali liquor outlet. According to the utility model, qualified regenerated acid and alkali can be prepared and reused in a smeltery, so that not only is the discharge of high-salinity wastewater reduced, but also the regenerated acid and alkali can be reused in the production process of the smeltery, and the production cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of wastewater treatment, in particular to an acid-base regeneration device for tungsten smelting high-salt wastewater. Background Art

[0002] Tungsten has a high melting point and high density, and is widely used in electronics, military industry, aerospace and other fields. Tungsten concentrate is the product of further enriching tungsten ore through beneficiation. There are two methods for smelting tungsten concentrate: pyrometallurgy and hydrometallurgy, but the alkali decomposition method is the most commonly used tungsten smelting method in the hydrometallurgy. The alkali decomposition process involves alkali boiling and ion exchange processes. The advantages of this process are short process flow and easy control of product quality. However, the biggest disadvantage of this process is that the wastewater discharge is large and the salt content is high. The wastewater discharged during its production process is typical high-salt wastewater (salt mass fraction>1%). Under normal production conditions, the total dissolved solids (TDS) content of the wastewater that meets the standards is about 1% to 2%, and the main components are chloride ions, sodium ions, sulfate ions, calcium ions, potassium ions, etc. The high-salt wastewater of tungsten smelters that meets the "Pollutant Discharge Standards for Urban Wastewater Treatment Plants" (GB18919-2002) is generally discharged directly into the river, but this inevitably has an impact on the environment.

[0003] At present, the main treatment method for high-salinity wastewater is membrane concentration-evaporation crystallization, but this method will lead to high treatment costs, and the resulting crystallized salt cannot be reused. Therefore, it is urgent to find a technical solution with low cost and high value utilization of high-salinity wastewater. Utility Model Content

[0004] In order to solve the above technical problems, the utility model provides an acid and alkali regeneration device for tungsten smelting high-salt wastewater, which can prepare regenerated qualified acid and alkali and reuse them in the smelter, not only reducing the discharge of high-salt wastewater, but also can reuse the regenerated acid and alkali in the production process of the smelter, reducing production costs.

[0005] The utility model adopts the following technical solutions:

[0006] A device for regenerating acid and alkali from high-salt wastewater from tungsten smelting comprises: a softening unit having a plurality of water treatment chemicals; a nanofiltration unit connected to the softening unit and used for removing sulfate radicals in the wastewater; a reverse osmosis unit connected to the nanofiltration unit, with a first output end connected to a fresh water storage mechanism; a bipolar membrane electrodialysis unit connected to the second output end of the reverse osmosis unit through a pump body, having an acid liquid outlet and an alkali liquid outlet, capable of preparing regenerated qualified acid and alkali and recycling them to a smelter, not only reducing the discharge of high-salt wastewater, but also recycling the regenerated acid and alkali to the production process of the smelter, reducing production costs, and having a reasonable process route design and high economic benefits.

[0007] Preferably, a pH adjustment tank is provided between the softening unit and the reverse osmosis unit, which can adjust the pH value of the waste liquid entering the reverse osmosis unit.

[0008] Preferably, the acid solution outlet and the alkali solution outlet are respectively connected to the acid solution storage mechanism and the alkali solution storage mechanism to store the acid solution and the alkali solution.

[0009] Preferably, the sodium chloride concentration in the tungsten smelting high-salt wastewater is at least 1.0%.

[0010] Preferably, the water treatment chemicals of the softening unit are polyacrylamide, polyferric sulfate and soda ash.

[0011] Preferably, the softening unit includes a softening tank, which includes a softening tank body and a stirring assembly located in the softening tank body. An overflow port is provided on one side of the softening tank body, and the lower end of the softening tank body is a sedimentation outlet. The stirring assembly is arranged at the bottom of the softening tank body through a support frame, and can stir the medicines and wastewater in the softening tank to accelerate the reaction speed.

[0012] Preferably, the stirring assembly includes a rotating motor and an agitator located at one end of the rotating motor, and the agitator includes a first stirring rod arranged horizontally and a second stirring rod arranged vertically. In addition to being used to stir the mixture of wastewater and chemicals, the first stirring rod can be used to stir the upper clear liquid, and the second stirring rod can be used to stir the lower sediment to prevent the sediment from adhering to the inner wall of the softening tank body.

[0013] Preferably, the support frame includes a connecting portion and a supporting portion circumferentially arranged on a side of the connecting portion, and there is a gap between adjacent supporting portions.

[0014] Compared with the prior art, the utility model has the following advantages: the utility model provides an acid and alkali regeneration device for high-salt wastewater from tungsten smelting, including a softening unit, a nanofiltration unit, a reverse osmosis unit, and a bipolar membrane electrodialysis unit, with an acid outlet and an alkali outlet, capable of preparing regenerated qualified acid and alkali and recycling them to the smelter, not only reducing the discharge of high-salt wastewater, but also recycling the regenerated acid and alkali to the production process of the smelter, reducing production costs, and the process route design is reasonable and the economic benefits are high. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the structure of the acid-base regeneration device for high-salt wastewater from tungsten smelting.

[0016] Figure 2 Schematic diagram of the structure of a bipolar membrane electrodialysis unit.

[0017] Figure 3 This is a schematic diagram of the structure of the softening tank.

[0018] Figure 4 A cross-sectional view of the softening tank.

[0019] Figure 5A partial cross-sectional view of the softening tank.

[0020] In the figure, a softening unit 1, a softening tank body 1-1, an overflow port 1-1-1, a sedimentation outlet 1-1-2, a stirring assembly 1-2, a support frame 1-2-1, a connecting portion 1-2-1-1, a supporting portion 1-2-1-2, a rotating motor 1-2-2, a first stirring rod 1-2-3, a second stirring rod 1-2-4, a nanofiltration unit 2, a reverse osmosis unit 3, a fresh water storage mechanism 4, a bipolar membrane electrodialysis unit 5, an acid outlet 5-1, an alkali outlet 5-2, a feed port 5-3, a pump body 6, a pH adjustment tank 7, an acid storage mechanism 8, and an alkali storage mechanism 9. DETAILED DESCRIPTION

[0021] In order to facilitate the understanding of the technical solution of the utility model, a detailed description is given below in conjunction with the accompanying drawings and specific embodiments.

[0022] Example 1

[0023] like Figure 1-2 As shown, a device for regenerating acid and alkali from high-salt wastewater from tungsten smelting includes:

[0024] Softening unit 1, having a plurality of water treatment chemicals, wherein the water treatment chemicals are polyferric sulfate, polyacrylamide and sodium carbonate;

[0025] The nanofiltration unit 2 is connected to the softening unit 1 and is used to remove sulfate from the wastewater;

[0026] The reverse osmosis unit 3 is connected to the nanofiltration unit 2, and the first output end is connected to the fresh water storage mechanism 4;

[0027] The bipolar membrane electrodialysis unit 5 is connected to the second output end of the reverse osmosis unit 3 through a pump body 6 and has an acid solution outlet 5 - 1 and an alkali solution outlet 5 - 2 .

[0028] The utility model can reuse the regenerated acid and alkali in the production process of the smelter, thereby reducing the production cost, and the process route is reasonably designed and has high economic benefits.

[0029] Specifically, a pH adjustment tank 7 is provided between the softening unit 1 and the reverse osmosis unit 3. Polyferric sulfate, polyacrylamide and sodium carbonate are added to the softening unit 1. After stirring and settling, the supernatant enters the pH adjustment tank 7 by overflow. In the pH adjustment tank 7, an appropriate amount of 20% hydrochloric acid is added to adjust the pH of the wastewater to 7-8, and the supernatant enters the nanofiltration unit 2 by overflow. The nanofiltration unit 2 is a nanofiltration device with a nanofiltration membrane, which can remove sulfate in the wastewater.

[0030] The wastewater from which sulfate is removed by the nanofiltration device enters the reverse osmosis unit 3; the high-concentration sodium chloride wastewater concentrated by the reverse osmosis unit 3 enters the bipolar membrane electrodialysis unit 5 through a high-pressure pump; wherein the first output end of the reverse osmosis unit 3 is connected to a fresh water barrel, so that the prepared fresh water can be stored; in addition, the bipolar membrane electrodialysis unit 5 has an acid outlet 5-1, an alkali outlet 5-2 and a feed port, and the wastewater enters from the feed port, and the acid and alkali prepared after the action of the bipolar membrane electrodialysis unit 5 are stored in the acid barrel and the alkali barrel respectively through the acid outlet 5-1 and the alkali outlet 5-2.

[0031] Among them, the sodium chloride concentration in the tungsten smelting high-salt wastewater is at least 1.0%; in this embodiment, taking the tungsten smelting high-salt wastewater discharged from a tungsten smelting plant in Jiangxi as an example, the sodium chloride concentration is about 1.6%, the chloride ion content is 9500mg / L, the sodium ion content is 7020mg / L, the calcium ion content is 520mg / L, and the sulfate content is 1330mg / L. After being treated by the above-mentioned tungsten smelting high-salt wastewater regeneration acid-base device, the final prepared fresh water has a chloride ion content of 670mg / L, a sodium ion content of 900mg / L, a trace calcium ion content, and a sulfate content of 8.4mg / L; in the final prepared acid solution, the hydrochloric acid concentration is 6.0%, the calcium ion content is trace, and the sulfate content is 97.5mg / L; in the final prepared alkali solution, the sodium hydroxide concentration is 6.8%, the calcium ion content is trace, and the sulfate content is 1.2mg / L.

[0032] Example 2

[0033] The difference between Example 2 and Example 1 is that the sodium chloride concentration in the tungsten smelting high-salt wastewater raw material is about 1.8%, the chloride ion content is 11640 mg / L, the sodium ion content is 7130 mg / L, the calcium ion content is 360 mg / L, and the sulfate content is 510 mg / L. After being treated by the above-mentioned tungsten smelting high-salt wastewater regeneration acid-base device, the final prepared fresh water has a chloride ion content of 940 mg / L, a sodium ion content of 200 mg / L, a trace calcium ion content, and a sulfate content of 1.5 mg / L; in the final prepared acid solution, the hydrochloric acid concentration is 6.2%, the calcium ion content is trace, and the sulfate content is 37.1 mg / L; in the final prepared alkali solution, the sodium hydroxide concentration is 6.9%, the calcium ion content is trace, and the sulfate content is 1.9 mg / L.

[0034] Example 3

[0035] The difference between Example 3 and Example 1 is that the sodium chloride concentration in the tungsten smelting high-salt wastewater raw material is about 2.1%, the chloride ion content is 12800mg / L, the sodium ion content is 8680mg / L, the calcium ion content is 630mg / L, and the sulfate content is 660mg / L. After being treated by the above-mentioned tungsten smelting high-salt wastewater regeneration acid-base device, the final prepared fresh water has a chloride ion content of 1300mg / L, a sodium ion content of 900mg / L, a trace calcium ion content, and a sulfate content of 8.4mg / L; in the final prepared acid solution, the hydrochloric acid concentration is 6.5%, the calcium ion content is trace, and the sulfate content is 47.9mg / L; in the final prepared alkali solution, the sodium hydroxide concentration is 7.0%, the calcium ion content is trace, and the sulfate content is 1.6mg / L.

[0036] In summary, Examples 1 to 3 obtained fresh water, acid solution and alkali solution of better quality after being treated by the above-mentioned tungsten smelting high-salt wastewater regeneration acid-alkali device.

[0037] Example 4

[0038] like Figure 3-5 As shown, the difference between Example 4 and Example 1 is that the softening unit 1 includes a softening tank, and the softening tank includes a softening tank body 1-1 and a stirring assembly 1-2 located in the softening tank body 1-1, and an overflow port 1-1-1 is provided on one side of the softening tank body 1-1, and the overflow port 1-1-1 is connected to the pH adjustment tank 7 through an overflow pipe; the lower end of the softening tank body 1-1 is a sedimentation outlet 1-1-2, which can discharge the sediment, and the stirring assembly 1-2 is arranged at the bottom of the softening tank body 1-1 through a support frame 1-2-1, and the stirring assembly 1-2 has a certain distance or a gap from the bottom of the softening tank body 1-1, which can ensure that the sediment is discharged smoothly through the sedimentation outlet 1-1-2.

[0039] Specifically, the stirring assembly 1-2 includes a rotating motor 1-2-2 and a stirrer located at one end of the rotating motor 1-2-2, the stirrer includes a rotating shaft connected to the driving end of the rotating motor 1-2-2, the rotating shaft is provided with a shaft sleeve, the shaft sleeve is provided with a first stirring rod 1-2-3 arranged horizontally, and the first stirring rod 1-2-3 is provided with a second stirring rod 1-2-4 arranged vertically. In the softening tank body 1-1, the upper layer is clear liquid and the lower layer is sediment. In addition to being used to stir the wastewater and the medicine, the first stirring rod 1-2-3 and the second stirring rod 1-2-4 can also stir the upper clear liquid through the first stirring rod 1-2-3 and stir the lower sediment through the second stirring rod 1-2-4 to prevent the sediment from adhering to the inner wall of the softening tank body 1-1.

[0040] The support frame 1-2-1 includes a connection part 1-2-1-1 located in the middle and a support part 1-2-1-2 circumferentially arranged on the side of the connection part 1-2-1-1. There is a gap between adjacent support parts 1-2-1-2 to facilitate the falling of sediment. The connection part 1-2-1-1 is a circular structure, and the rotating motor 1-2-2 is connected to the lower surface of the connection part 1-2-1-1, and its driving shaft is arranged through the connection part 1-2-1-1; in addition, in order to prevent the rotating motor 1-2-2 from entering water, a waterproof shell can be arranged on the surface of the rotating motor 1-2-2.

[0041] The above are only preferred embodiments of the present invention. The protection scope of the present invention shall be based on the scope defined by the claims. Several improvements and modifications made by those skilled in the art without departing from the spirit and scope of the present invention shall also be regarded as the protection scope of the present invention.

Claims

1. A device for regenerating acid and alkali from high-salt wastewater from tungsten smelting, characterized in that: include: A softening unit (1) having a plurality of water treatment chemicals; A nanofiltration unit (2) is connected to the softening unit (1) and is used to remove sulfate from the wastewater; A reverse osmosis unit (3) is connected to the nanofiltration unit (2), and a first output end is connected to a fresh water storage mechanism (4); The bipolar membrane electrodialysis unit (5) is connected to the second output end of the reverse osmosis unit (3) via a pump body (6) and has an acid solution outlet (5-1) and an alkali solution outlet (5-2).

2. The acid-base regeneration device for high-salt wastewater from tungsten smelting according to claim 1 is characterized in that: A pH adjustment tank (7) is provided between the softening unit (1) and the reverse osmosis unit (3).

3. The acid-base regeneration device for tungsten smelting high-salt wastewater according to claim 1 is characterized in that: The acid solution outlet (5-1) and the alkali solution outlet (5-2) are respectively connected to the acid solution storage mechanism (8) and the alkali solution storage mechanism (9).

4. The acid-base regeneration device for tungsten smelting high-salt wastewater according to claim 1 is characterized in that: The sodium chloride concentration in tungsten smelting high-salt wastewater is at least 1.0%.

5. The acid-base regeneration device for tungsten smelting high-salt wastewater according to claim 1 is characterized in that: The water treatment chemicals of the softening unit (1) are polyacrylamide, polyferric sulfate and soda ash.

6. The acid-base regeneration device for tungsten smelting high-salt wastewater according to claim 1 is characterized in that: The softening unit (1) comprises a softening tank, the softening tank comprising a softening tank body (1-1) and a stirring assembly (1-2) located in the softening tank body (1-1), a water overflow port (1-1-1) being provided on one side of the softening tank body (1-1), a sedimentation outlet (1-1-2) being provided at the lower end of the softening tank body (1-1), and the stirring assembly (1-2) being arranged at the bottom of the softening tank body (1-1) via a support frame (1-2-1).

7. The acid-base regeneration device for high-salt wastewater from tungsten smelting according to claim 6 is characterized in that: The stirring assembly (1-2) comprises a rotating motor (1-2-2) and a stirrer located at one end of the rotating motor (1-2-2), and the stirrer comprises a first stirring rod (1-2-3) arranged horizontally and a second stirring rod (1-2-4) arranged vertically.

8. The acid-base regeneration device for high-salt wastewater from tungsten smelting according to claim 7 is characterized in that: The support frame (1-2-1) comprises a connecting portion (1-2-1-1) and a supporting portion (1-2-1-2) circumferentially arranged on a side surface of the connecting portion (1-2-1-1), and gaps are provided between adjacent supporting portions (1-2-1-2).

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