Production line capable of efficiently separating COD and meeting wastewater MVR evaporation
By optimizing the organic wastewater treatment process and adopting processes such as ozone oxidation, Fenton oxidation and activated carbon adsorption, the problem of increased COD concentration in high-concentration organic wastewater during the MVR salt distillation process was solved, efficient COD separation was achieved, the treatment process was simplified and the quality of the salt distillation was improved.
Patent Information
- Application Number
- CN202422909838.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-27
- Publication Date
- 2025-10-28
- Estimated Expiration
- 2034-11-27
AI Technical Summary
In the existing technology, the COD concentration of high-concentration organic wastewater increases during the MVR salt distillation process, resulting in an increase in the wastewater treatment load, affecting the stable operation of the system, and the salt distillation has a darker color, making it difficult to meet national quality standards.
A production line including a raw water tank, an ozone reactor, a Fenton neutralization reactor, a filter press, an activated carbon adsorption precipitator, a decalcified raw water tank and an MVR evaporator is adopted. Through processes such as ozone oxidation, Fenton oxidation, neutralization reaction and activated carbon adsorption, the treatment process is optimized to avoid the increase of COD concentration and improve the treatment efficiency.
It achieves efficient separation of COD, simplifies the organic wastewater treatment process, reduces the treatment load, and ensures that the quality of steamed salt meets national standards. After treatment, the water sample is clear and the steamed salt is white and non-viscous.
Smart Images
Figure CN223480973U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of resource scheduling technology, specifically to a production line that efficiently separates COD to meet the requirements of wastewater MVR evaporation. Background Technology
[0002] Chemical Oxygen Demand (COD), as an important parameter for measuring the degree of water pollution, has always received much attention. COD is a chemical measure of the amount of reducing substances in a water sample that need to be oxidized. A higher COD value indicates a higher content of reducing substances in the water sample, and it is commonly used to assess the content of organic pollutants in wastewater. Excessive COD in water bodies consumes large amounts of dissolved oxygen, accelerates water quality deterioration, and seriously harms the ecological environment and biological health. Therefore, treating COD in water bodies to reduce its content is essential.
[0003] The main sources of COD include domestic sewage, industrial wastewater, and agricultural wastewater. Currently, some companies use Mechanical Vapor Recompression (MVR) technology in their zero-discharge wastewater treatment processes. This process requires pretreatment and concentration of the wastewater, followed by evaporation and crystallization to separate salts from the wastewater. Commonly used organic wastewater pretreatment technologies include advanced oxidation processes, electrochemical methods, membrane separation methods, and biological methods.
[0004] Among these methods, advanced oxidation is widely used for high-concentration, low-flow organic wastewater, characterized by short reaction times, fast reaction rates, and easy process control, capable of completely degrading various organic pollutants. Electrochemical methods are mainly suitable for small-scale wastewater treatment plants or chlor-alkali enterprises with small water volumes; however, their electrode materials wear out quickly, resulting in low efficiency, and they are not suitable for wastewater treatment with large fluctuations in water quality. Membrane separation methods have high investment and subsequent operating costs, and are generally used for recovering useful components from wastewater or for water reuse. While biological methods have low operating costs, they have high requirements for wastewater conditions, require large land areas, and are complex to manage.
[0005] In industrial production processes, organic wastewater undergoes MVR (Mechanical Vapor Removal and Control) salt distillation after pretreatment. As water evaporates, the concentration of COD (Chemical Oxygen Demand) in the mother liquor gradually increases. When the COD concentration in the wastewater is high, the system requires more energy and time to treat the wastewater, thus increasing the treatment load. This not only prolongs the treatment time but may also affect the stable operation of the system. Furthermore, during the evaporation and crystallization process, high-concentration organic wastewater can cause COD to adhere to the surface or interior of the precipitated salt, resulting in a darker color in the distilled salt and failing to meet relevant national quality standards. Utility Model Content
[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a production line that efficiently separates COD for wastewater MVR evaporation. By optimizing the overall structure of the production line, the problem of increased wastewater treatment load due to increased COD concentration during salt distillation of organic wastewater is avoided, thus making the treatment of organic wastewater simpler and more efficient.
[0007] To achieve the above objectives, the present invention adopts the following technical solution:
[0008] A high-efficiency COD separation production line that meets the requirements of wastewater MVR evaporation is characterized by:
[0009] The production line includes, in sequence, a raw water tank, an ozone reactor, a neutralization reactor, a filter press liquid tank, a first filter press, a filter press clear liquid tank, an adsorption precipitator, a decalcified raw water tank, an evaporator, and a circulation tank.
[0010] According to one aspect of the above technical solution, the circulating pool and the ozone reactor are also connected by a first circulating pipe so that wastewater entering the circulating pool can be circulated into the ozone reactor for reaction.
[0011] According to one aspect of the above technical solution, the adsorption precipitator is also connected to the first filter press via a second circulation pipeline, so that the bottom sludge precipitated by the adsorption precipitator can be circulated into the first filter press for filtration.
[0012] According to one aspect of the above technical solution, the neutralization reactor is a Fenton neutralization reactor.
[0013] According to one aspect of the above technical solution, the Fenton neutralization reactor is provided with a first Fenton reaction tank and a second Fenton reaction tank, as well as a first lime neutralization reaction tank and a second lime neutralization reaction tank.
[0014] According to one aspect of the above technical solution, the first Fenton reaction tank, the second Fenton reaction tank, the first lime neutralization reaction tank and the second lime neutralization reaction tank are connected in series, and the raw water passes through the first Fenton reaction tank, the second Fenton reaction tank, the first lime neutralization reaction tank and the second lime neutralization reaction tank in sequence.
[0015] According to one aspect of the above technical solution, the adsorption precipitator is an activated carbon adsorption precipitator.
[0016] According to one aspect of the above technical solution, the activated carbon adsorption precipitator is provided with an activated carbon adsorption reaction tank and a precipitator.
[0017] According to one aspect of the above technical solution, the evaporator is an MVR evaporator.
[0018] According to one aspect of the above technical solution, a second filter press is also provided between the decalcified raw water tank and the evaporator.
[0019] Compared with existing technologies, the production line for efficient COD separation that meets the requirements of MVR evaporation of wastewater, as shown in this utility model, has the following advantages:
[0020] This production line includes, in sequence, a raw water tank, an ozone reactor, a Fenton neutralization reactor, a filter press liquid tank, a filter press, a filter press clear liquid tank, an activated carbon adsorption precipitator, a decalcified raw water tank, an MVR evaporator, and a circulation tank. By using the production line shown in this invention, and introducing organic wastewater sequentially into each treatment device or structure, the problem of increased COD concentration leading to increased wastewater treatment load during salt removal from organic wastewater can be avoided, thus making the treatment of organic wastewater simpler and more efficient. Attached Figure Description
[0021] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:
[0022] Figure 1 This is a structural block diagram of a production line that satisfies the requirements of efficient COD separation during wastewater MVR evaporation in one embodiment of the present invention.
[0023] Component symbol explanation in the attached diagram:
[0024] Raw water tank 1, ozone reactor 2, neutralization reactor 3, filter press liquid tank 4, first filter press 5, second filter press 5a, filter press clear liquid tank 6, adsorption precipitator 7, decalcified raw water tank 8, evaporator 9, circulation tank 10. Detailed Implementation
[0025] To make the objectives, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model are described in detail below with reference to the accompanying drawings. Several embodiments of this utility model are shown in the drawings. However, this utility model can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of this utility model more thorough and complete.
[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0027] Example 1
[0028] Please see Figure 1 The first embodiment of this utility model provides a production line for efficient COD separation that meets the requirements of MVR evaporation of wastewater. The production line includes a raw water tank 1, an ozone reactor 2, a neutralization reactor 3, a filter press liquid tank 4, a first filter press 5, a filter press clear liquid tank 6, an adsorption precipitator 7, a decalcified raw water tank 1, an evaporator 9, and a circulation tank 10 connected in sequence.
[0029] The circulating tank 10 and the ozone reactor 2 are connected by a first circulating pipe to allow wastewater entering the circulating tank 10 to be recycled into the ozone reactor 2 for reaction. The adsorption precipitator 7 and the first filter press 5 are connected by a second circulating pipe to allow the bottom sludge settled by the adsorption precipitator 7 to be recycled into the first filter press 5 for filtration.
[0030] In this embodiment, neutralization reactor 3 is a Fenton neutralization reactor 3.
[0031] The Fenton neutralization reactor 3 is equipped with a first Fenton reaction tank and a second Fenton reaction tank, as well as a first lime neutralization reaction tank and a second lime neutralization reaction tank.
[0032] Specifically, the first Fenton reaction tank, the second Fenton reaction tank, the first lime neutralization reaction tank, and the second lime neutralization reaction tank are connected in series, and the raw water passes through the first Fenton reaction tank, the second Fenton reaction tank, the first lime neutralization reaction tank, and the second lime neutralization reaction tank in sequence.
[0033] In this embodiment, the adsorption precipitator 7 is an activated carbon adsorption precipitator 7.
[0034] The activated carbon adsorption precipitator 7 is equipped with an activated carbon adsorption reaction tank and a precipitator.
[0035] In this embodiment, the evaporator 9 is an MVR evaporator 9.
[0036] In this embodiment, a second filter press 5a is also provided between the decalcified raw water tank 1 and the evaporator 9.
[0037] In this embodiment, the production line first introduces high-concentration mixed organic wastewater into raw water tank 1 for storage. Then, the effluent from raw water tank 1 is sent to ozone reactor 2 for thorough oxidation. The ozone-oxidized effluent then enters the first and second Fenton reaction tanks, where ferrous sulfate and hydrogen peroxide are added respectively for further oxidation. After further oxidation, the effluent enters the first and second neutralization reaction tanks, where lime slurry is added for neutralization. This ensures that the organic pollutants in the wastewater are efficiently oxidized and removed, allowing it to be subsequently treated in a salt distillation system. The effluent from the neutralization reaction and the activated carbon adsorption sediment from the subsequent stage are collected in the filter press liquid tank 4 and then fed into the filter press for filtration. The filter residue is returned to the production system, while the collected filter clear liquid enters the filter clear liquid tank 6 and is pumped into the subsequent activated carbon adsorption precipitator 7 for further COD and color removal. The adsorbed sediment is then pumped back to the filter press liquid tank 4 for filtration. The supernatant effluent flows by gravity into the subsequent softening system for decalcification treatment. The decalcified wastewater is then sent to the MVR evaporation system for salt distillation. The final evaporated waste salt is general solid waste. The mother liquor with a higher COD concentration obtained after the MVR salt distillation process enters the circulation tank 10 and is pumped into the ozone reactor 2 along with the raw water for oxidation pretreatment, etc. After meeting the requirements, it undergoes salt distillation again.
[0038] In ozone reactor 2, the ozone dosage is 0.14–0.18 m³ / h, and the oxidation time is 30–60 min, which can maintain a good oxidation effect.
[0039] More specifically, the Fenton neutralization reactor is divided into four compartments. The first two compartments are Fenton reaction tanks, namely the first Fenton reaction tank and the second Fenton reaction tank, which are used to add ferrous sulfate solution and hydrogen peroxide to react with the incoming raw water, respectively, with a residence time of 30-60 minutes. The last two compartments are lime neutralization reaction tanks, namely the first lime neutralization reaction tank and the second lime neutralization reaction tank, which are used to add lime slurry solution to react sequentially, with a residence time of 30-60 minutes.
[0040] More specifically, the activated carbon adsorption precipitator 7 consists of an activated carbon adsorption reaction tank and a precipitator. Powdered activated carbon solution is added and reacted fully with the filtered liquid to adsorb and remove color from the water. The adsorption reaction time is 30-60 minutes and the precipitation time is 1-2 hours.
[0041] More specifically, the wastewater decalcification treatment process used in the decalcification raw water tank 1 adopts any one of the following methods, including but not limited to the dual alkali method, the sodium carbonate method, and the CO2 decalcification method.
[0042] Specific examples:
[0043] The wastewater source is organic wastewater from a flue gas scrubbing process, with a COD content of 6220 mg / L and a color of 300. In view of the high COD content and high color of the water sample, this embodiment adopts the process of "ozone oxidation + Fenton oxidation + activated carbon adsorption" to treat the organic wastewater from the flue gas scrubbing process.
[0044] The high-concentration organic wastewater from flue gas scrubbing is first stored in raw water tank 1. The effluent from raw water tank 1 is then sent to ozone reactor 2 for complete oxidation, with an ozone flow rate of 0.16 m³ / min. 3 The reaction time is 30–60 min. The Fenton neutralization reaction section is one of the core sections of this treatment process. To achieve the desired reaction effect, the first two compartments are Fenton reaction tanks. After the ozone-oxidized effluent enters the Fenton reaction tanks, ferrous sulfate solution and hydrogen peroxide (2 g / L and 20 mL / L of ferrous sulfate and hydrogen peroxide, respectively) are added to react with the raw water, with a residence time of 30–60 min. The last two compartments are lime neutralization reaction tanks. After further oxidation, the water sample enters the neutralization reaction tank and 10% lime slurry solution is added for neutralization to adjust the pH of the water sample to 7, with a residence time of 30–60 min. The effluent from the neutralization reaction and the activated carbon adsorption sediment from the subsequent stage are collected in the filter press liquid tank 4 and then introduced into the filter press for filtration. The filter residue is returned to the production system. The collected filter clear liquid enters the filter clear liquid tank 6 and is pumped into the subsequent activated carbon adsorption reaction tank. Activated carbon is added to it for adsorption for 30-60 minutes to further remove COD and color (the amount of activated carbon added is 5g / L). The sedimentation time is 1-2 hours. The adsorption sediment is pumped back to the filter press liquid tank 4 for filtration. The supernatant effluent can enter the subsequent softening system. The wastewater softening treatment adopts the sodium carbonate method. The softened and calcium-removed water sample finally enters the MVR evaporator 9 for salt removal.
[0045] Using the production line and operating process described in this embodiment, the COD content in the treated water sample was 1840 mg / L, the color was reduced to 20, the treated effluent was clear, and the distilled salt was white and non-viscous, indicating that the production line shown in this embodiment has a good effect on treating organic wastewater from flue gas scrubbing. Finally, the mother liquor with a higher COD concentration obtained after the MVR salt distillation operation enters the circulation tank 10 and is pumped together with the raw water into the ozone reactor 2 for oxidation pretreatment, etc. After meeting the requirements, salt distillation is performed again.
[0046] In summary, compared with existing technologies, the production line for efficient COD separation that meets the requirements of wastewater MVR evaporation, as shown in this embodiment, has the following advantages:
[0047] This production line includes, in sequence, a raw water tank, an ozone reactor, a Fenton neutralization reactor, a filter press liquid tank, a filter press, a filter press clear liquid tank, an activated carbon adsorption precipitator, a decalcified raw water tank, an MVR evaporator, and a circulation tank. By using the production line shown in this invention, and introducing organic wastewater sequentially into each treatment device or structure, the problem of increased COD concentration leading to increased wastewater treatment load during salt removal from organic wastewater can be avoided, thus making the treatment of organic wastewater simpler and more efficient.
[0048] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0049] The above-described embodiments are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.
Claims
1. A production line for efficient COD separation that meets the requirements of wastewater MVR evaporation, characterized in that: The production line includes, in sequence, a raw water tank, an ozone reactor, a neutralization reactor, a filter press liquid tank, a first filter press, a filter press clear liquid tank, an adsorption precipitator, a decalcified raw water tank, an evaporator, and a circulation tank.
2. The production line for high-efficiency COD separation that satisfies wastewater MVR evaporation according to claim 1, characterized in that, The circulating pool and the ozone reactor are also connected by a first circulating pipe, so that the wastewater entering the circulating pool can be circulated into the ozone reactor for reaction.
3. The production line for efficient COD separation that satisfies wastewater MVR evaporation according to claim 2, characterized in that, The adsorption precipitator is also connected to the first filter press via a second circulation pipe, so that the sediment settled by the adsorption precipitator can be circulated into the first filter press for filtration.
4. The production line for high-efficiency COD separation that satisfies wastewater MVR evaporation according to claim 1, characterized in that, The neutralization reactor is a Fenton neutralization reactor.
5. The production line for efficient COD separation in wastewater MVR evaporation according to claim 4, characterized in that, The Fenton neutralization reactor is provided with a first Fenton reaction tank and a second Fenton reaction tank, as well as a first lime neutralization reaction tank and a second lime neutralization reaction tank.
6. The production line for efficient COD separation in wastewater MVR evaporation according to claim 5, characterized in that, The first Fenton reaction tank, the second Fenton reaction tank, the first lime neutralization reaction tank, and the second lime neutralization reaction tank are connected in series, and the raw water passes through the first Fenton reaction tank, the second Fenton reaction tank, the first lime neutralization reaction tank, and the second lime neutralization reaction tank in sequence.
7. The production line for efficient COD separation that satisfies wastewater MVR evaporation according to claim 1, characterized in that, The adsorption precipitator is an activated carbon adsorption precipitator.
8. The production line for efficient COD separation that satisfies wastewater MVR evaporation according to claim 7, characterized in that, The activated carbon adsorption precipitator is equipped with an activated carbon adsorption reaction tank and a precipitator.
9. The production line for high-efficiency COD separation that satisfies wastewater MVR evaporation according to claim 1, characterized in that, The evaporator is an MVR evaporator.
10. The production line for efficient COD separation based on wastewater MVR evaporation according to any one of claims 1-9, characterized in that, A second filter press is also provided between the decalcified raw water tank and the evaporator.