A high-salt high-fluoride ion chemical wastewater treatment system

Abstract

The utility model relates to a kind of high-salt high-fluoride ion chemical industrial wastewater treatment systems, comprising: multistage defluorination unit, for removing fluorine ion in wastewater multiple times;Evaporator, for removing salt in wastewater;A 2 O biochemical system, for removing organic matter, total nitrogen, COD, ammonia nitrogen pollutant in wastewater. By multistage defluorination unit, effectively remove super high concentration fluorine ion, then use evaporator to remove salt in wastewater, recover crystalline salt, condensed wastewater can directly enter biochemical system processing, after the treatment of whole set of system, system effluent reaches discharge standard. The utility model by multistage defluorination unit, evaporator and A 2 O The reasonable combination and synergistic effect of biochemical system realize the efficient removal of fluorine ion, salt and various pollutants in high-salt high-fluoride ion chemical industrial wastewater, with significant technical effect and engineering application advantage.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment technology, and in particular to a high-salt, high-fluoride ion chemical wastewater treatment system. Background Technology

[0002] With the continuous advancement of industrialization and urbanization, the discharge of industrial wastewater from various industrial production activities has been increasing. Among them, fluoride-containing wastewater, as a typical inorganic pollutant, has received widespread attention due to its wide range of sources, difficulty in treatment, and significant environmental hazards. Fluoride-containing wastewater generally refers to wastewater containing fluorides (mainly in the form of fluoride ions F). - Industrial wastewater (in its current form) with a concentration exceeding the relevant emission standards, if discharged directly without effective treatment, will have adverse effects on the ecological environment and human health.

[0003] Fluoride-containing wastewater is generated across a wide range of industries, primarily including chemical, non-ferrous metal smelting, coking, electroplating, and textile printing and dyeing. Additionally, it is generated during metal welding and smelting, as well as in ceramic and glass manufacturing. Fluorides have strong bioaccumulation and toxicity. Long-term intake of excessive fluoride can lead to health problems such as dental fluorosis and bone fluorosis, and also poses potential harm to the nervous and endocrine systems. Furthermore, when fluoride-containing wastewater enters natural water bodies or soil environments, it can inhibit the growth of aquatic organisms, soil microorganisms, and plants, disrupting the balance of ecosystems. Therefore, various countries have established relatively strict limits on the concentration of fluoride emissions in industrial wastewater, which sets higher standards for fluoride-containing wastewater treatment technologies.

[0004] However, treating fluoride-containing wastewater presents certain technical challenges. On the one hand, fluoride ions have high solubility in water and are chemically stable, making them difficult to remove through simple physical separation methods. On the other hand, actual industrial fluoride-containing wastewater is complex, often accompanied by high salinity, high alkalinity, or the coexistence of other inorganic ions and organic pollutants, making it more difficult to control the reaction conditions during treatment. Furthermore, improper control during treatment can easily generate large amounts of fluoride-containing sludge, increasing the burden of subsequent disposal and operating costs.

[0005] In conclusion, the treatment of fluoride-containing wastewater is an urgent and important task. There is a pressing need to develop a more rationally structured, more efficient, lower-cost, and more adaptable technology or device for treating fluoride-containing wastewater to overcome the shortcomings of existing technologies and achieve efficient and stable treatment of fluoride-containing wastewater, thereby better protecting the ecological environment and human health. Utility Model Content

[0006] The technical problem to be solved by this utility model is to overcome the shortcomings of the existing technology and provide a high-salt, high-fluoride ion chemical wastewater treatment system.

[0007] This utility model is achieved through the following technical solution: A high-salt, high-fluoride ion chemical wastewater treatment system includes: Multi-stage defluorination unit, used to remove fluoride ions from wastewater multiple times; Evaporation equipment is used to remove salt from wastewater; A 2 The O-biochemical system is used to remove organic matter, total nitrogen, COD, and ammonia nitrogen pollutants from wastewater.

[0008] According to the above technical solution, preferably, the multi-stage defluorination unit includes: The defluorination reactor is equipped with quicklime, calcium chloride, PAC, and PAM reagents for the first defluorination process. Micro-electrolysis reactors are used to decompose organic pollutants in wastewater; Coagulation flotation equipment is used for secondary defluorination and mud-water separation; In addition to hard reactors, sodium carbonate, sodium hydroxide, PAC, and PAM are added to reduce the hardness of the materials. The defluorination resin tower is used for the third defluorination process, reducing the fluoride ion concentration to below 10 mg / L.

[0009] According to the above technical solution, preferably, the multi-stage defluorination unit further includes a raw water tank and an intermediate water tank, and the defluorination reactor, raw water tank, micro-electrolysis reactor, coagulation flotation equipment, intermediate water tank, hardening reactor, and defluorination resin tower are arranged in sequence.

[0010] According to the above technical solution, preferably, a sludge dewatering machine is provided between the defluorination reactor and the raw water tank, and the coagulation flotation equipment and the hardening reactor are both connected to a sludge thickening tank, which is connected to the sludge dewatering machine.

[0011] According to the above technical solution, preferably, quicklime, calcium chloride, PAC and PAM are added to the defluorination reactor to achieve coagulation and sedimentation, and the pH is adjusted to weak alkalinity. The solution is then pumped into the sludge dewatering machine for sludge-water separation, and the filtrate enters the raw water tank.

[0012] According to the above technical solution, preferably, the A 2 The O-biochemical system is a combined biochemical process of "hydrolysis-anoxic-aerobic" to remove organic matter, total nitrogen, COD, and ammonia nitrogen pollutants from wastewater.

[0013] According to the above technical solution, preferably, it further includes: The wastewater first enters the oil-water separation sedimentation tank and is then discharged into the defluorination reactor by a lift pump.

[0014] The beneficial effects of this utility model are: This invention effectively removes ultra-high concentrations of fluoride ions through a multi-stage defluorination unit, then uses an evaporation device to remove salt from the wastewater and recover crystalline salt. The condensed wastewater can be directly treated in a biological system. After treatment by the entire system, the effluent meets the discharge standards, demonstrating significant technical effects and engineering application advantages.

[0015] This invention utilizes a multi-stage defluorination unit, an evaporation device, and A... 2 The rational combination and synergistic effect of the O-biochemical system achieves efficient removal of fluoride ions, salts and various pollutants from high-salt and high-fluoride chemical wastewater. It solves the technical problems of low fluoride removal efficiency, poor system stability and limited biochemical treatment in existing technologies, and enables the system effluent to stably meet the discharge standards or reuse requirements. It has significant effects such as good treatment effect, stable operation and strong adaptability. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the system connection of this utility model.

[0017] In the diagram: 1. Oil-water separator sedimentation tank; 2. Defluoridation reactor; 3. Sludge dewatering machine A; 4. Raw water tank; 5. Micro-electrolysis reactor; 6. Coagulation and flotation equipment; 7. Intermediate water tank; 8. Hardness removal reactor; 9. Defluoridation resin tower; 10. Evaporation device; 11. Equalization tank; 12. A 2 O Biochemical system; 13. Sludge thickening tank; 14. Sludge dewatering machine B. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and preferred embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0019] In the description of the utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the utility model.

[0020] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "setting," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection, an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0021] As shown in the figure, this utility model includes, in sequence, an oil-water separation sedimentation tank 1, a defluorination reactor 2, a sludge dewatering machine, a raw water tank 4, a micro-electrolysis reactor 5, a coagulation and flotation device 6, an intermediate water tank 7, a hardening reactor 8, a defluorination resin tower 9, an evaporation device 10, a regulating water tank 11, and A. 2 O Biochemical System 12. This system includes a multi-stage defluorination unit consisting of a defluorination reactor 2, a sludge dewatering machine, a micro-electrolysis reactor 5, a coagulation and flotation device 6, a hardening reactor 8, and a defluorination resin tower 9, used to remove high concentrations of fluoride ions from wastewater multiple times. An evaporation device 10 is used to remove salts from the wastewater. A 2 The O-Biochemical System 12 is used to remove organic matter, total nitrogen, COD, and ammonia nitrogen pollutants from wastewater.

[0022] Specifically, the outlet of the oil-water separation primary sedimentation tank is connected to the inlet of the defluorination reactor 2; the outlet of the defluorination reactor 2 is connected to the inlet of the sludge dewatering machine; the outlet of the sludge dewatering machine is connected to the inlet of the raw water tank 4; the outlet of the raw water tank 4 is connected to the inlet of the micro-electrolysis reactor 5; the outlet of the micro-electrolysis reactor 5 is connected to the inlet of the coagulation flotation device 6; the outlet of the coagulation flotation device 6 is connected to the inlet of the intermediate water tank 7; the outlet of the intermediate water tank 7 is connected to the inlet of the hardening reactor 8; the outlet of the hardening reactor 8 is connected to the inlet of the defluorination resin tower 9; the outlet of the defluorination resin tower 9 is connected to the inlet of the evaporation device 10; the outlet of the evaporation device 10 is connected to the inlet of the equalization water tank 11; and the outlet of the equalization water tank 11 is connected to A 2 The inlet of the O biochemical system 12 is connected.

[0023] Wastewater first enters the oil-water separator sedimentation tank 1. The wastewater in the sedimentation tank 1 is then pumped into the defluorination reactor 2. In the defluorination reactor 2, quicklime, calcium chloride, PAC, and PAM are added to achieve coagulation and sedimentation while adjusting the pH to a slightly alkaline state. The addition of quicklime and calcium chloride in the defluorination reactor 2 causes fluoride ions in the wastewater to preferentially react with calcium ions to form insoluble calcium fluoride precipitate. This, combined with PAC and PAM, achieves highly efficient coagulation and sedimentation, significantly reducing the fluoride ion concentration and suspended solids content in the wastewater at the system's front end, thus reducing the load on subsequent treatment units. Due to the extremely high amount of precipitate, the sludge and water cannot be separated into layers and need to be pumped into the sludge dewatering machine A3 for sludge-water separation. The filtrate then enters the raw water tank 4.

[0024] The raw water tank 4 is equipped with a lift pump to pump wastewater into the micro-electrolysis reactor 5, which is used to decompose organic pollutants in the wastewater. The micro-electrolysis process can destroy the molecular structure of some recalcitrant organic matter, improve the biodegradability of wastewater, and at the same time promote the formation of more easily removed forms of some fluorides and metal ions, creating favorable conditions for subsequent coagulation, flotation and biochemical treatment.

[0025] The effluent from the micro-electrolysis reactor 5 enters the coagulation-flotation equipment 6, which serves for secondary defluorination and sludge-water separation, further removing residual fluoride ions and fine suspended solids, making the wastewater quality more stable. The effluent then enters the intermediate water tank 7. The intermediate water tank 7 is equipped with a lift pump to pump the wastewater into the hardening reactor 8, where sodium carbonate, sodium hydroxide, PAC, and PAM are added. This reduces hardness, prevents scaling in subsequent treatment equipment, ensures long-term stable system operation, significantly extends the service life of the defluorination resin and evaporation equipment, and reduces operating and maintenance costs. In this example, both the coagulation-flotation equipment 6 and the hardening reactor 8 are connected to a sludge thickening tank 13, which is connected to a sludge dewatering machine B14.

[0026] The effluent enters the defluorination resin tower 9 for a third defluorination process, ensuring that the fluoride ion concentration drops below 10 mg / L. This effectively overcomes the problem that traditional chemical precipitation methods cannot achieve stable low-concentration compliance, thus meeting more stringent discharge or reuse requirements.

[0027] The effluent then enters the evaporation unit 10 for desalination treatment, and the evaporated condensate enters the equalization tank 11. The equalization tank 11 is equipped with a lift pump to pump the wastewater into A. 2 O Biochemical System 12 performs biochemical treatment, A 2 The O-Biochemical System 12 employs a combined biochemical process of "hydrolysis-anoxic-aerobic." Hydrolysis primarily utilizes anaerobic bacteria to decompose organic matter in the wastewater, improving its biodegradability. Anoxic processes primarily utilize facultative anaerobic bacteria for denitrification, removing total nitrogen pollutants from the wastewater. Aerobic processes primarily utilize aerobic bacteria to remove COD and ammonia nitrogen pollutants from the wastewater. The biochemically treated wastewater meets discharge standards.

[0028] In summary, this application provides a high-salt, high-fluoride ion chemical wastewater treatment system. Through a multi-stage defluorination unit, it effectively removes ultra-high concentrations of fluoride ions. Then, an evaporation device is used to remove salt from the wastewater and recover crystalline salt. The condensed wastewater can be directly fed into a biological treatment system. After treatment by the entire system, the effluent meets the discharge standards. This system achieves highly efficient removal of fluoride ions, salt, and various pollutants from high-salt, high-fluoride ion chemical wastewater, demonstrating significant technical effects and engineering application advantages.

[0029] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A high-salt, high-fluoride ion chemical wastewater treatment system, characterized in that, include: Multi-stage defluorination unit, used to remove fluoride ions from wastewater multiple times; Evaporation device (10) for removing salt from wastewater; A 2 The O biochemical system (12) is used to remove organic matter, total nitrogen, COD and ammonia nitrogen pollutants from wastewater.

2. The high-salt, high-fluoride ion chemical wastewater treatment system according to claim 1, characterized in that, The multi-stage defluorination unit includes: In the defluorination reactor (2), quicklime, calcium chloride, PAC and PAM reagents are added for the first defluorination. Micro-electrolysis reactor (5) is used to decompose organic pollutants in wastewater; A coagulation flotation device (6) is used for secondary defluorination and mud-water separation; In addition to the hard reactor (8), sodium carbonate, sodium hydroxide, PAC and PAM are added to reduce the hardness of the material. The defluorination resin tower (9) is used for the third defluorination to reduce the fluoride ion concentration to below 10 mg / L.

3. The high-salt, high-fluoride ion chemical wastewater treatment system according to claim 2, characterized in that, The multi-stage defluoridation unit also includes a raw water tank (4) and an intermediate water tank (7). The defluorination reactor (2), raw water tank (4), micro-electrolysis reactor (5), coagulation flotation equipment (6), intermediate water tank (7), hardening reactor (8), and defluorination resin tower (9) are arranged in sequence.

4. The high-salt, high-fluoride ion chemical wastewater treatment system according to claim 3, characterized in that, A sludge dewatering machine is installed between the defluorination reactor (2) and the raw water tank (4). The coagulation flotation equipment (6) and the hardening reactor (8) are both connected to a sludge thickening tank (13), and the sludge thickening tank (13) is connected to a sludge dewatering machine.

5. The high-salt, high-fluoride ion chemical wastewater treatment system according to claim 4, characterized in that, The defluorination reactor (2) is filled with quicklime, calcium chloride, PAC and PAM to achieve coagulation and sedimentation, and the pH is adjusted to weak alkalinity. The solution is then pumped into the sludge dewatering machine for sludge-water separation, and the filtrate enters the raw water tank (4).

6. The high-salt, high-fluoride ion chemical wastewater treatment system according to claim 1, characterized in that, The A 2 The O biochemical system (12) is a biochemical combination process of "hydrolysis-anoxic-aerobic" to remove organic matter, total nitrogen, COD and ammonia nitrogen pollutants from wastewater.

7. The high-salt, high-fluoride ion chemical wastewater treatment system according to any one of claims 2-5, characterized in that, Also includes: The wastewater first enters the oil-water separation sedimentation tank (1) and is then discharged into the defluorination reactor (2) by a lift pump.

Images