Waste water defluorination device

Abstract

The utility model discloses a waste water defluorination device, which belongs to the technical field of waste water treatment and comprises a water inlet, a PH adjusting chamber and a defluorination reaction chamber, the water inlet is arranged at the PH adjusting chamber, an acid liquor inlet is further arranged in the PH adjusting chamber, and the PH adjusting chamber is communicated with the defluorination reaction chamber through a first connecting pipe, so that before the defluorination process starts officially, the acid liquor inlet is communicated with the defluorination reaction chamber through a second connecting pipe. According to the method, the pH value of the wastewater can be adjusted, so that silicate is replaced, then a fluorine removal agent is added, a full reaction is performed, and a fluosilicic acid complex system is destroyed, so that a relatively high fluorine ion removal rate is obtained, and the problem that silicate and fluoride contained in the lepidolite beneficiation wastewater can form a fluosilicic acid complex in the prior art is solved. The precipitation of fluorine ions and calcium ions in the wastewater is influenced, so that the fluorine removal efficiency is relatively low.

Description

Technical Field

[0001] The utility model relates to the technical field of wastewater treatment, in particular to a wastewater defluorination device. Background Art

[0002] In recent years, with the rapid development of the new energy industry and low-carbon economy, especially the breakthrough and popularization of large-capacity power battery technology, the new energy vehicle industry has risen rapidly, and the demand for lithium products has been increasing.

[0003] Lepidolite ore is one of the important resources for lithium extraction. A certain amount of production wastewater will be generated during the beneficiation process of lepidolite. Most of the production wastewater is recycled after being treated in the factory, and a small part is discharged. The production wastewater contains a certain concentration of fluoride. Excessive fluoride will cause the death of aquatic organisms and the destruction of the ecological balance. Long-term drinking of water with excessive fluoride may lead to fluorosis, which has a serious impact on human health. Therefore, before discharging, it is necessary to defluorinate the lepidolite ore dressing wastewater.

[0004] Conventional defluorination uses calcium-based defluorinating agents such as calcium hydroxide and calcium chloride for precipitation, so that fluoride ions form insoluble calcium fluoride precipitates with calcium ions and are removed. Since the silicate contained in the lepidolite ore dressing wastewater will form a fluorosilicate complex with fluoride, it will affect the precipitation of fluoride ions and calcium ions in the wastewater, resulting in low defluorination efficiency.

[0005] For example, the "mine fluoride-containing wastewater treatment system" disclosed in the Chinese patent literature, with the publication number CN213060492U, includes a raw water tank, a pipeline mixer, a defluorination water purifier, a first filter, a second filter and a resin filter. The raw water tank is connected to the defluorination water purifier through a first pipeline, and a raw water lift pump and the pipeline mixer are arranged on the first pipeline; the defluorination water purifier is connected to the first filter through a second pipeline; the first filter and the second filter are respectively connected to the resin filter, and the resin filter is connected to a buffer tank through a third pipeline. The disadvantage of this patent is that during precipitation, the silicate contained in the lepidolite ore dressing wastewater will form a fluorosilicate complex with fluoride, affecting the precipitation of fluoride ions and calcium ions in the wastewater, resulting in low defluorination efficiency. Content of the Utility Model

[0006] The utility model aims to overcome the problem in the prior art that the silicate contained in the lepidolite ore dressing wastewater will form a fluorosilicate complex with fluoride, affecting the precipitation of fluoride ions and calcium ions in the wastewater, resulting in low defluorination efficiency, and provides a wastewater defluorination device that can improve the defluorination efficiency.

[0007] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0008] The utility model relates to a waste water defluorination device, which includes a water inlet, a pH adjustment chamber and a defluorination reaction chamber. The water inlet is arranged at the pH adjustment chamber, and an acid liquid inlet is also arranged in the pH adjustment chamber. The pH adjustment chamber is communicated with the defluorination reaction chamber through a first connecting pipe.

[0009] The pH of the spodumene ore dressing waste water is above 10.0, showing strong alkalinity. And due to the presence of silicate in the waste water, a fluosilicate complex is formed with fluoride ions. Conventional agents and treatment devices are difficult to achieve good removal effects. After using calcium-based defluorinating agents such as calcium hydroxide and calcium chloride for reaction and precipitation, the removal rate of fluoride ions is less than 10%. Therefore, in this application, by adding a pH adjustment chamber and an acid liquid inlet in the defluorination device, the pH value of the waste water can be adjusted before the formal start of the defluorination process, so that the silicate is displaced, and then a defluorinating agent is added for sufficient reaction to destroy the fluosilicate complex system, thereby obtaining a higher fluoride ion removal rate.

[0010] Preferably, stirrers are installed in both the pH adjustment chamber and the defluorination reaction chamber. The stirrer in the pH adjustment chamber is used to accelerate the replacement speed of silicate and improve the overall efficiency.

[0011] Preferably, the defluorination reaction chamber is communicated with a coagulation reaction chamber through a second connecting pipe, and a stirrer is also installed in the coagulation reaction chamber. The coagulation reaction chamber is used for defluorination reaction, and the stirring by the stirrer can accelerate the defluorination reaction and improve the overall efficiency.

[0012] Preferably, the coagulation reaction chamber is communicated with a flocculation reaction chamber through a third connecting pipe, and a stirrer is also installed in the flocculation reaction chamber. The flocculation reaction chamber is used for flocculation reaction to form larger alum flowers from the fine flocs generated after the reaction in the coagulation reaction chamber.

[0013] Preferably, the stirrer includes a rotating shaft and stirring blades.

[0014] Preferably, the stirring blades include connecting rods in the radial direction of the rotating shaft and stirring rods parallel to the axial direction of the rotating shaft. The structures of the connecting rods and the stirring rods are used to increase the stirring area and avoid being subjected to large resistance during the stirring process, thereby reducing the load of the driving structure.

[0015] Preferably, this application further includes an inclined tube sedimentation chamber, which successively includes an effluent area, an inclined tube sedimentation area and a sludge discharge area from top to bottom.

[0016] Preferably, a conical hopper is installed in the sludge discharge area, a sludge discharge port is arranged on the lower side of the conical hopper, and the sludge discharge port is connected with a sludge discharge pump through a sludge discharge pipeline.

[0017] Preferably, a weir is arranged at the effluent area.

[0018] Therefore, the utility model has the following beneficial effects: (1) It can improve the fluoride ion removal rate; (2) The defluorination efficiency is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a top view schematic diagram of the utility model.

[0020] Figure 2 is the utility model in Figure 1 A sectional view taken along line A-A.

[0021] Figure 3 is the utility model in Figure 1 A sectional view taken along line B-B.

[0022] Figure 4 is the utility model in Figure 1 A sectional view taken along line C-C.

[0023] Figure 5 is a pipeline schematic diagram of the first embodiment of the utility model.

[0024] Figure 6 is a pipeline schematic diagram of the second embodiment of the utility model.

[0025] In the figure: PH adjustment chamber 1, defluorination reaction chamber 2, coagulation reaction chamber 3, flocculation reaction chamber 4, inclined tube sedimentation chamber 5, water inlet 6, water outlet weir 7, first connecting pipe 8, second connecting pipe 9, third connecting pipe 10, connecting channel 11, hydrochloric acid feeding port 12, defluorinating agent feeding port 13, coagulant feeding port 14, flocculant aid feeding port 15, stirrer 16, sludge discharge area 17, inclined tube sedimentation area 18, water outlet area 19, sludge discharge hopper 20, conical hopper 21, sludge discharge pump 22. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The following further describes the utility model in conjunction with the drawings and specific embodiments.

[0027] Embodiment 1, as Figures 1-5 shown, a wastewater defluorination device for defluorinating spodumene beneficiation wastewater, which includes a reaction area and a sedimentation area. The reaction area is provided with a water inlet 6, and the sedimentation area is provided with a water outlet weir 7. The reaction area includes a PH adjustment chamber 1, a defluorination reaction chamber 2, a coagulation reaction chamber 3, and a flocculation reaction chamber 4. The sedimentation area includes an inclined tube sedimentation chamber 5.

[0028] The water inlet 6 is arranged at the pH adjustment chamber 1. An acid solution inlet is also provided in the pH adjustment chamber 1. Specifically, the acid solution inlet is a hydrochloric acid feeding port 12, through which hydrochloric acid can be added into the pH adjustment chamber 1. Moreover, a pH probe and a pH meter box are installed in the pH adjustment chamber 1. The hydrochloric acid feeding port 12 is controlled by a hydrochloric acid feeding pump for feeding. The hydrochloric acid feeding pump is linked and controlled with the pH probe. By real-time monitoring the pH value in the current pH adjustment chamber 1, the start and stop of hydrochloric acid feeding and the amount of feeding are controlled, so as to ensure that the pH value in the pH adjustment chamber 1 always remains within the set range. At the same time, a stirrer 16 is also installed in the pH adjustment chamber 1, and the stirrer 16 accelerates the mixing of the wastewater and hydrochloric acid.

[0029] The pH of the spodumene beneficiation wastewater is above 10.0, showing strong alkalinity. And due to the presence of silicate in the wastewater, a fluosilicic acid complex is formed with fluoride ions. Conventional agents and treatment devices are difficult to achieve good removal effects. After using calcium-based defluorinating agents such as calcium hydroxide and calcium chloride for reaction and precipitation, the removal rate of fluoride ions is less than 10%.

[0030] In this application, by adding a pH adjustment chamber 1 in the defluorination device and setting a hydrochloric acid feeding port 12 in the pH adjustment chamber 1, before the formal start of the defluorination process, the pH value of the wastewater can be adjusted by hydrochloric acid, so that the silicate is displaced.

[0031] The pH adjustment chamber 1 is communicated with the defluorination reaction chamber 2 through a first connecting pipe 8. A pipe mixer is installed on the first connecting pipe 8. A defluorinating agent feeding port 13 is provided in the front section of the pipe mixer, so that the defluorinating agent and the wastewater with adjusted pH value are evenly mixed in the pipe mixer and enter the defluorination reaction chamber 2. A stirrer 16 is also installed in the defluorination reaction chamber 2. Under the stirring of the stirrer 16, the wastewater undergoes a defluorination reaction to break the fluosilicic acid complex system, so that fluoride ions combine with the defluorinating agent to form insoluble substances.

[0032] The defluorination reaction chamber 2 is communicated with the coagulation reaction chamber 3 through a second connecting pipe 9. A coagulant feeding port 14 is provided on the second connecting pipe 9. The coagulant is specifically polyaluminum chloride. Through the stirring effect of the water flow itself, the wastewater after the defluorination reaction is mixed with the coagulant and enters the coagulation reaction chamber 3. A stirrer 16 is also installed in the coagulation reaction chamber 3. Under the stirring of the stirrer 16, the wastewater undergoes a coagulation reaction, so that the insoluble substances and the coagulant form fine flocs.

[0033] There are two coagulation reaction chambers 3, and the two coagulation reaction chambers 3 are respectively arranged on both sides of the flocculation reaction chamber 4. The second connecting pipe 9 is a tee pipe, which diverts the wastewater after the defluorination reaction into the two coagulation reaction chambers 3 for reaction.

[0034] The coagulation reaction chamber 3 is communicated with the flocculation reaction chamber 4 through a third connecting pipe 10. The outlet of the third connecting pipe 10 is located near the bottom of the flocculation reaction chamber 4. A coagulant aid feeding port 15 is provided on the third connecting pipe 10. The coagulant aid is specifically polyacrylamide. The coagulant aid and the wastewater after coagulation reaction enter the flocculation reaction chamber 4 together. A stirrer 16 is also installed in the flocculation reaction chamber 4. The stirring speed of the stirrer 16 in the flocculation reaction chamber 4 is lower than that of the previous several stirrers 16. Under the stirring of the stirrer 16, a flocculation reaction is carried out to form larger alum flowers from small flocs.

[0035] The above-mentioned stirrer 16 includes a rotating shaft and stirring blades. The rotating shaft is driven to rotate by a stirring motor. The stirring motor is installed on the top of each regulating chamber. The rotating shaft is vertically arranged in the regulating chamber. The stirring blades include a connecting rod in the radial direction of the rotating shaft and a stirring rod parallel to the axial direction of the rotating shaft. The connecting rod can increase the stirring area in the radial direction of the rotating shaft, and the stirring rod can increase the stirring area in the axial direction of the rotating shaft. A ladder for the operation and maintenance personnel to climb is installed on the side of the reaction zone. Through the ladder, personnel can climb to the top of the reaction zone to maintain each stirring motor and part of the pipeline.

[0036] The flocculation reaction chamber 4 is connected to the inclined tube sedimentation chamber 5 through a connecting channel 11. The inclined tube sedimentation chamber 5 successively includes a water outlet area 19, an inclined tube sedimentation area 18 and a sludge discharge area 17 from top to bottom. The water outlet weir 7 is located at the water outlet area 19. The opening of the connecting channel 11 in the flocculation reaction chamber 4 is located in the upper part of the flocculation reaction chamber 4, while the opening of the connecting channel 11 in the inclined tube sedimentation chamber 5 is located in the lower part of the inclined tube sedimentation chamber 5, that is, in the sludge discharge area 17. A sludge hopper is provided at the bottom of the sludge discharge area 17. A conical hopper 21 is installed above the sludge hopper. The conical hopper 21 is inverted conical, and a sludge discharge port is provided below the conical hopper 21. By blocking above the sludge discharge port through the conical hopper 21, it can be avoided that the wastewater is directly sucked into the sludge discharge port without sedimentation separation. The inclined tube sedimentation area 18 is filled with inclined tube fillers. The solids formed by the flocculation reaction in the wastewater will be discharged in the sludge discharge area 17, and the remaining sewage will flow upward. The sludge contained in the sewage will be sedimented when passing through the inclined tube sedimentation area 18 and fall back into the sludge hopper. The sludge discharge port is connected to a sludge discharge pump 22 through a sludge discharge pipeline. Through the sludge discharge pump 22, the sludge in the sludge hopper 20 can be sucked out.

[0037] The utility model solves the difficult problem of difficult removal of fluorine in fluosilicate complexes by reasonably controlling the operation condition parameters. When the influent fluoride ion content of the lepidolite ore dressing wastewater is 39 mg / L, after being treated by this device, the effluent fluoride ion content is reduced to 4.3 mg / L, and the removal rate reaches 89%.

[0038] Example 2, as Figure 6 shown, a waste water defluorination device is used for defluorination treatment of lepidolite ore dressing waste water. It includes a reaction zone and a precipitation zone. An inlet 6 is provided in the reaction zone, and an effluent weir 7 is provided in the precipitation zone. The reaction zone includes a pH adjustment chamber 1, a defluorination reaction chamber 2, a coagulation reaction chamber 3, and a flocculation reaction chamber 4. The precipitation zone includes an inclined tube precipitation chamber 5.

[0039] The inlet 6 is arranged at the pH adjustment chamber 1. An acid liquid inlet is also provided in the pH adjustment chamber 1. The acid liquid inlet is specifically a hydrochloric acid feeding port 12, and hydrochloric acid can be added into the pH adjustment chamber 1. Moreover, a pH probe and a pH meter box are installed in the pH adjustment chamber 1. The hydrochloric acid feeding port 12 is controlled for feeding through a hydrochloric acid feeding pump, and the hydrochloric acid feeding pump is linked with the pH probe to control the start and stop of hydrochloric acid feeding and the amount of feeding through real-time monitoring of the pH value in the current pH adjustment chamber 1, so as to ensure that the pH value in the pH adjustment chamber 1 always remains within the set range. At the same time, a stirrer 16 is also installed in the pH adjustment chamber 1, and the stirrer 16 accelerates the mixing of the waste water and hydrochloric acid.

[0040] The pH of the lepidolite ore dressing waste water is above 10.0, showing strong alkalinity. And due to the presence of silicate in the waste water, a fluorosilicate complex is formed with fluoride ions. Conventional agents and treatment devices are difficult to achieve good removal effects. After reaction and precipitation with calcium-based defluorinating agents such as calcium hydroxide and calcium chloride, the removal rate of fluoride ions is less than 10%.

[0041] In this application, by adding a pH adjustment chamber 1 in the defluorination device and setting a hydrochloric acid feeding port 12 in the pH adjustment chamber 1, before the formal start of the defluorination process, the pH value of the waste water can be adjusted by hydrochloric acid, so that the silicate is displaced.

[0042] The pH adjustment chamber 1 is communicated with the defluorination reaction chamber 2 through a first connecting pipe 8, and the waste water after pH value adjustment enters the defluorination reaction chamber 2. A stirrer 16 is also installed in the defluorination reaction chamber 2. Under the stirring of the stirrer 16, the waste water undergoes a defluorination reaction to destroy the fluorosilicate complex system, so that fluoride ions combine with the defluorinating agent to form an insoluble substance. The difference from Example 1 is that in this embodiment, the defluorinating agent feeding port 13 is directly arranged in the defluorination reaction chamber 2, and the defluorinating agent is continuously added while stirring, and the mixing of the defluorinating agent and the waste water is realized by the stirrer 16 at the same time.

[0043] The defluorination reaction chamber 2 and the coagulation reaction chamber 3 are connected through a second connecting pipe 9. The wastewater that has undergone the defluorination reaction enters the coagulation reaction chamber 3. A stirrer 16 is also installed in the coagulation reaction chamber 3. Under the agitation of the stirrer 16, the wastewater undergoes a coagulation reaction, causing the insoluble substances and the coagulant to form fine flocs. Different from the first embodiment, in this embodiment, a coagulant feeding port 14 is provided in the coagulation reaction chamber 3. The coagulant is specifically polyaluminum chloride. Under the agitation of the stirrer 16, the coagulant and the wastewater are mixed simultaneously.

[0044] There are two coagulation reaction chambers 3, which are respectively arranged on both sides of the flocculation reaction chamber 4. The second connecting pipe 9 is a tee pipe, which diverts the wastewater that has undergone the defluorination reaction into the two coagulation reaction chambers 3 for reaction.

[0045] The coagulation reaction chamber 3 is connected to the flocculation reaction chamber 4 through a third connecting pipe 10. The outlet of the third connecting pipe 10 is located near the bottom of the flocculation reaction chamber 4. The wastewater that has undergone the coagulation reaction enters the flocculation reaction chamber 4. A stirrer 16 is also installed in the flocculation reaction chamber 4. The stirring speed of the stirrer 16 in the flocculation reaction chamber 4 is lower than that of the previous stirrers 16. Under the agitation of the stirrer 16, a flocculation reaction occurs, causing the fine flocs to form larger flocculent masses. Different from the first embodiment, in this embodiment, a coagulant aid feeding port 15 is provided in the flocculation reaction chamber 4. The coagulant aid is specifically polyacrylamide. Under the agitation of the stirrer 16, the coagulant aid and the wastewater are mixed simultaneously.

[0046] The above-mentioned stirrer 16 includes a rotating shaft and stirring blades. The rotating shaft is driven to rotate by a stirring motor. The stirring motor is installed on the top of each regulating chamber. The rotating shaft is vertically arranged in the regulating chamber. The stirring blades include a connecting rod in the radial direction of the rotating shaft and a stirring rod parallel to the axial direction of the rotating shaft. The connecting rod can increase the stirring area in the radial direction of the rotating shaft, and the stirring rod can increase the stirring area in the axial direction of the rotating shaft. A ladder for the operation and maintenance personnel to climb is installed on the side of the reaction area. Through the ladder, personnel can climb to the top of the reaction area to maintain each stirring motor and some pipelines.

[0047] The flocculation reaction chamber 4 and the inclined tube sedimentation chamber 5 are connected through a connection channel 11. The inclined tube sedimentation chamber 5 sequentially includes an effluent area 19, an inclined tube sedimentation area 18, and a sludge discharge area 17 from top to bottom. The effluent weir 7 is located at the effluent area 19. The opening of the connection channel 11 in the flocculation reaction chamber 4 is located at the upper part of the flocculation reaction chamber 4, while the opening of the connection channel 11 in the inclined tube sedimentation chamber 5 is located at the lower part of the inclined tube sedimentation chamber 5, that is, in the sludge discharge area 17. A sludge hopper is provided at the bottom of the sludge discharge area 17, and a conical hopper 21 is installed above the sludge hopper. The conical hopper 21 is an inverted cone, and a sludge discharge port is provided below the conical hopper 21. By blocking above the sludge discharge port through the conical hopper 21, it is possible to prevent the wastewater from being directly sucked into the sludge discharge port without sedimentation separation. The inclined tube sedimentation area 18 is filled with inclined tube packing. The solids formed after flocculation reaction in the wastewater will be discharged in the sludge discharge area 17, and the remaining sewage will flow upward. The sludge contained in the sewage will be sedimented when passing through the inclined tube sedimentation area 18 and fall back into the sludge hopper. The sludge discharge port is connected to a sludge discharge pump 22 through a sludge discharge pipeline. Through the sludge discharge pump 22, the sludge in the sludge discharge hopper 20 can be sucked out.

[0048] The utility model solves the problem that it is difficult to remove fluorine in the fluorosilicate complex by reasonably controlling the operating condition parameters. When the influent fluoride ion content of the lepidolite ore dressing wastewater is 39 mg / L, after being treated by this device, the effluent fluoride ion content is reduced to 4.3 mg / L, and the removal rate reaches 89%.

Claims

1. A wastewater defluorination device, comprising a water inlet, characterized in that: It includes a pH regulating chamber and a defluorination reaction chamber, the water inlet is arranged at the pH regulating chamber, an acid liquid inlet is also arranged in the pH regulating chamber, the pH regulating chamber is connected with the defluorination reaction chamber through a first connecting pipe, and also includes an inclined tube sedimentation chamber, the inclined tube sedimentation chamber includes a mud discharge area, a conical bucket is installed in the mud discharge area, and a mud discharge port is arranged on the lower side of the conical bucket.

2. A wastewater defluorination device according to claim 1, characterized in that: Agitators are installed in the pH adjustment chamber and the defluorination reaction chamber.

3. A wastewater defluorination device according to claim 2, characterized in that: The defluorination reaction chamber is connected to the coagulation reaction chamber through a second connecting pipe, and an agitator is also installed in the coagulation reaction chamber.

4. A wastewater defluorination device according to claim 3, characterized in that: The coagulation reaction chamber is connected with the flocculation reaction chamber through a third connecting pipe, and a stirrer is also installed in the flocculation reaction chamber.

5. A wastewater defluorination device according to any one of claims 2 to 4, characterized in that: The stirrer comprises a rotating shaft and stirring blades.

6. A wastewater defluorination device according to claim 5, characterized in that: The stirring blade includes a connecting rod located in the radial direction of the rotating shaft and a stirring rod parallel to the axial direction of the rotating shaft.

7. A wastewater defluorination device according to claim 1, characterized in that: The inclined tube sedimentation chamber comprises a water outlet area, an inclined tube sedimentation area and a mud discharge area from top to bottom.

8. A wastewater defluorination device according to claim 7, characterized in that: The mud discharge port is connected with the mud discharge pump through a mud discharge pipeline.

9. A wastewater defluorination device according to claim 7, characterized in that: A water outlet weir is provided at the water outlet area.

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