A treatment device for vegetable processing wastewater

Abstract

This invention addresses the problems of low treatment efficiency, high treatment cost, and secondary wastewater pollution caused by existing methods for treating high-COD, high-nitrogen, and high-phosphorus vegetable wastewater. A treatment device for vegetable processing wastewater includes a sedimentation tank with an internal screen dividing it into a feeding trough and a discharging trough. The discharging trough is connected to one end of an inlet pipe, the other end of which is connected to a fermentation tank. The fermentation tank outlet is connected to the inlet of an outlet pipe, which in turn is connected to the inlet of a treatment tank. The treatment tank outlet is connected to the inlet of a reaction tank. This device offers advantages such as high treatment efficiency, low operating costs, and no secondary pollution, providing a solution for the treatment of high-concentration organic wastewater. By optimizing dissolved air efficiency and flocculation separation methods, rapid wastewater purification and resource utilization are achieved.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment technology, specifically to a treatment device for vegetable processing wastewater. Background Technology

[0002] The treatment of vegetable wastewater is a significant environmental issue. Its pollutants are complex, rich in high concentrations of organic matter, primarily cellulose, protein, and sugars, with COD values ​​typically reaching hundreds of thousands of ppm. Current treatment methods for high-concentration vegetable wastewater mainly include biochemical methods, conventional air flotation, and flocculation sedimentation; however, these technologies have significant drawbacks in terms of efficiency, cost, and secondary pollution control.

[0003] Against this backdrop, nanobubbles with a diameter ≤50 μm have shown great potential in wastewater treatment due to their high specific surface area, long residence time, and strong oxidation capacity. This technology integrates micro-nanobubbles with flotation, biological adsorption, and resource utilization technologies, achieving not only efficient pollutant removal but also reducing operating costs. Conventional wastewater treatment methods, such as biochemical methods, utilize microbial metabolism to degrade organic matter and are suitable for treating low-concentration wastewater. Furthermore, the high COD and nutrient concentrations in vegetable wastewater inhibit microbial activity, leading to low treatment efficiency. Traditional dissolved air flotation (DAF) typically has a dissolved air efficiency of less than 1%, resulting in bubbles larger than 100 μm and a small number, making it difficult to effectively capture tiny flocs. Ordinary flotation achieves only 40%-60% COD removal, requiring multiple stages such as flocculation and sedimentation to barely meet discharge standards. In recent years, micro-nanobubbles with a diameter ≤50 μm have demonstrated great potential in wastewater treatment due to their high specific surface area, long residence time, and strong oxidation capacity.

[0004] The treatment of wastewater from vegetable processing is a crucial aspect of controlling agricultural non-point source pollution. Traditional technologies, due to their low efficiency, high cost, and secondary pollution, are insufficient to meet current environmental protection requirements. This invention integrates micro-nano bubble synergistic flotation, biological adsorption, and resource utilization technologies, achieving not only highly efficient pollutant removal but also reduced operating costs. Summary of the Invention

[0005] This invention addresses the problems of low treatment efficiency, high treatment cost, and secondary wastewater pollution caused by existing methods for treating high-COD, high-nitrogen-phosphorus vegetable wastewater. To address the aforementioned issues, this patent proposes an integrated device based on micro / nano bubble synergistic flotation. By optimizing dissolved air efficiency and flocculation separation methods, it achieves rapid wastewater purification and resource utilization. Specifically, this application is implemented through the following technical solution: A treatment device for vegetable processing wastewater includes a sedimentation tank, wherein a screen is installed inside the sedimentation tank, dividing the sedimentation tank into a feeding trough and a discharging trough. The discharge trough of the sedimentation tank is connected to one end of the inlet pipe, the other end of the inlet pipe is connected to the fermentation tank, the outlet of the fermentation tank is connected to the inlet of the discharge pipe, the outlet of the discharge pipe is connected to the inlet of the treatment tank, and the outlet of the treatment tank is connected to the inlet of the reaction tank.

[0006] An electric scraper is installed at the top opening of the reaction tank.

[0007] The bottom of the reaction tank is connected to the output port of the generator.

[0008] The outlet pipe at the bottom of the reaction tank is also connected to a filter.

[0009] The reaction tank is filled with PAC and PAM flocculants.

[0010] The inlet pipe is equipped with a one-way valve, which controls the flow direction to flow into the fermentation tank.

[0011] The outlet pipe is equipped with a one-way valve, which controls the flow direction to flow into the treatment tank.

[0012] The treatment tank is connected to an air pump, the outlet of which is connected to an exhaust pipe with several exhaust holes.

[0013] The electric scraper is provided with a flocculent collection trough at the lower end.

[0014] The filter outlet is connected to a collection tank.

[0015] Preferably, the filter contains a number of ceramic particles.

[0016] Compared with the prior art, the beneficial effects of this utility model are as follows: 1. Integrated wastewater purification is achieved through a series of interconnected sedimentation tanks and screens, fermentation tanks, treatment tanks, and reaction tanks. The reaction tank utilizes micro-nano bubbles in conjunction with flotation to treat the wastewater. This invention offers advantages such as high treatment efficiency, low operating costs, and no secondary pollution, providing a solution for the treatment of high-concentration organic wastewater. It has practical significance and economic benefits for the treatment of vegetable wastewater. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the vegetable wastewater purification device of this utility model.

[0018] Figure 2 This is a schematic diagram of the operation of the vegetable wastewater purification device of this utility model.

[0019] Figure reference numerals: Sedimentation tank 1, screen 2, inlet pipe 201, fermentation tank 3, outlet pipe 301, treatment tank 4, air pump 401, exhaust pipe 402, reaction tank 5, outlet 501, electric scraper 6, generator 7, filter 8, collection tank 9, collection trough 10.

[0020] Figure 2 In the diagram, A represents sediment in the wastewater, and B represents flocculent residue from air flotation. Detailed Implementation

[0021] It should be understood that the terms "internal," "one end," "the other end," "inlet," "outlet," "top," etc., indicating orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention 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, and therefore should not be construed as a limitation on the present invention. The model numbers selected in this patent are only for the convenience of explanation and are not a limitation requiring the use of such instrument models.

[0022] Example 1 like Figures 1-2 As shown, a treatment device for vegetable processing wastewater includes a sedimentation tank 1. The sedimentation tank 1 is equipped with a screen 2, which divides the sedimentation tank 1 into a feeding trough and a discharging trough. The discharge trough of sedimentation tank 1 is connected to one end of inlet pipe 201, and the other end of inlet pipe 201 is connected to fermentation tank 3. The outlet of fermentation tank 3 is connected to the inlet of discharge pipe 301, the outlet of discharge pipe 301 is connected to the inlet of treatment tank 4, and the outlet of treatment tank 4 is connected to the inlet of reaction tank 5.

[0023] An electric scraper 6 is installed at the top opening of the reaction tank 5.

[0024] The bottom of reaction tank 5 is connected to the output port of generator 7.

[0025] The water outlet pipe 501 at the bottom of the reaction tank 5 is also connected to the filter 8.

[0026] Reaction tank 5 is filled with PAC and PAM flocculants.

[0027] The inlet pipe 201 is equipped with a one-way valve, which controls the flow direction to flow into the fermentation tank 3.

[0028] The outlet pipe 301 is equipped with a one-way valve, which controls the flow direction to flow into the treatment tank 4.

[0029] The treatment tank 4 is connected to an air pump 401, the outlet of which is connected to an exhaust pipe 402, which has several exhaust holes.

[0030] A sludge collection trough 10 is provided below the end of the electric scraper 6.

[0031] The outlet of filter 8 is connected to the collection tank 9.

[0032] Preferably, filter 8 is filled with a number of ceramic particles.

[0033] Preferably, the spacing between the bars of the grille 2 is 10mm.

[0034] Preferably, fermentation tank 3 is an anaerobic fermentation tank, containing anaerobic microorganisms, including Clostridium species such as Clostridium acetobutanol, Bacteroides species such as Bacteroides polymorpha, Syntrophobic bacteria species such as Syntrophobicia warwickii, Methanobacter species such as Methanobacter formate, and Methanococcus species such as Methanococcus vannamei. These bacteria originate from the initial wastewater.

[0035] Preferably, the temperature of fermentation tank 3 is 55-60℃ and the pH is 6.8-7.2.

[0036] The tilt angle of the electric scraper 6 is 10°~15°.

[0037] Preferably, the concentration of bacterial strains per unit volume of wastewater in fermentation tank 3 is 10~30 g / L. Preferably, treatment tank 4 is an aerobic deep treatment tank, and the aerobic microorganisms include bacteria, fungi, and protozoa; among them, bacteria include Pseudomonas putidae, Bacillus licheniformis, etc.; fungi include yeast, mold, etc.; and protozoa include Paramecium, Amoeba, etc.

[0038] Preferably, the concentration of bacterial strains per unit volume of wastewater in treatment tank 4 is 2-4 g / L. Preferably, the temperature of treatment tank 4 is 20-40℃, and the pH is 6.5-8.5. Air pump 401 was purchased from Shanghai Zhongqiu Pump Industry Co., Ltd., model 40KFD-4.

[0039] The flow rate of air pump 401 is set to 20~30m³. 3 / (m 2 *h).

[0040] Preferably, reaction tank 5 is a micro-nano air flotation reaction tank.

[0041] Preferably, the electric scraper 6 is purchased from Shandong Longxin Environmental Protection Co., Ltd., model ZBGN-16. The installation height of the electric scraper 6 is set at the flocculant flotation liquid surface of the reaction tank 5.

[0042] Preferably, generator 7 is a micro-nano bubble generator, which was purchased from Shandong Shuiyuqing Environmental Engineering Co., Ltd., model: WSZ-10t / d.

[0043] Preferably, filter 8 contains a number of ceramic particles; the ceramic particles are purchased from Anhui Yusong Ceramic Particle Technology Co., Ltd., and the model is 1-3mm.

[0044] Preferably, the PAC was purchased from Gongyi Songyang Water Purification Materials Co., Ltd., model: plate and frame type.

[0045] Preferably, the PAM is purchased from Weilan Polyacrylamide manufacturer, with a molecular weight of 10 million to 14 million.

[0046] The above-mentioned device processing method includes the following steps: a. Collect the vegetable wastewater into the feeding tank of sedimentation tank 1, where the mud and sand in the wastewater settle. b. Install screen 2 in sedimentation tank 1. When wastewater passes through screen 2, it intercepts vegetable residue and enters fermentation tank 3. Anaerobic fermentation reaction takes 3-8 days to coarsely degrade and settle the vegetable residue. c. After the fermentation reaction in fermentation tank 3 is completed, the wastewater enters treatment tank 4. Air is introduced into treatment tank 4, and the aerobic reaction lasts for 3-5 days. d. The wastewater after the aerobic reaction enters reaction tank 5. The dosage of PAC and PAM flocculants is shown in Table 1, per 10000 mg / L COD. Cr The wastewater was treated with 2.5 kg of PAC per 100 L of wastewater and 0.1 kg of PAM per 100 L of wastewater. e. Use an electric scraper 6 to collect the sediment from the air flotation, and discharge the filtered water from the filter 8 into the collection tank 9.

[0047] This method was used to analyze COD levels of 20000 mg / L. Cr The wastewater raw water was treated, and the quality of the wastewater raw water and the treated water is shown in Table 2.

[0048] Taking the daily treatment of 10 tons of vegetable wastewater as an example: Table 1. Dosage of Drugs

[0049] Note: Table 1 shows the dosing rates for PAC and PAM determined based on a raw wastewater feed rate of 100 L / min.

[0050] Table 2. Water quality data of vegetable wastewater, unit: mg / L

[0051] The wastewater treatment process using a vegetable processing wastewater treatment device is as follows: Wastewater enters the feeding trough of sedimentation tank 1. The silt and sand in the wastewater will remain at the bottom of sedimentation tank 1, while large suspended solids will be intercepted by the grid 2 installed behind the feeding trough. The wastewater then enters fermentation tank 3, which is connected to the discharge trough of sedimentation tank 1. In fermentation tank 3, anaerobic microorganisms in the wastewater decompose the organic matter. After 3-8 days of anaerobic fermentation, the wastewater, now anaerobic, enters treatment tank 4. Air is introduced into treatment tank 4 by an air pump 401. The aerobic microorganisms carried in the original wastewater in treatment tank 4 further decompose and transform the organic pollutants in the wastewater, including glucose and starch, further reducing the dissolved organic matter in the water, including methanol, acetic acid, amino acids, and humic acid. In addition, through the action of nitrifying bacteria, such as *Nitrosomonas cerevisiae* and *Nitrobacterium nitrificationum*, ammonia nitrogen in the wastewater is converted into nitrate nitrogen, achieving denitrification. This process takes 3-5 days.

[0052] The wastewater treated in treatment tank 4 enters reaction tank 5 through a connected pipe. PAC and PAM flocculants are added to reaction tank 5 according to the COD concentration. Air is dissolved in the wastewater using generator 7, which injects bubbles with a diameter of less than 50 micrometers into the wastewater inside reaction tank 5. Suspended particles or grease in reaction tank 5 float to the surface under the buoyancy of the bubbles, and solid-liquid separation is achieved by an electric scraper 6. The flocculated water discharged from reaction tank 5 is filtered through a filter 8 and meets the discharge standards of "Urban Wastewater Discharge Standard GB18918-2002".

[0053] In reaction tank 5, the addition rates of PAC and PAM are 7.5 L / h and 8.0 L / h, respectively. An electric scraper 6 removes the flocculent residue from the air flotation, which can then be used as agricultural fertilizer in farmland. The dissolved air pressure in generator 7 is 0.21 MPa, and the bubble diameter is ≤50 μm. Filter 8 is filled with ceramsite with a particle size of 1-3 mm, used to adsorb Fe and Al ions.

[0054] Furthermore, the description of this invention is merely a preferred embodiment and is not intended to limit the invention. Although the invention has been described in detail with reference to the embodiments, those skilled in the art can still modify the technical solutions described in the embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the protection scope of this invention.

Claims

1. A vegetable processing tail wastewater treatment device comprising a sedimentation tank (1), characterized in that, The sedimentation tank (1) is equipped with a grid (2) inside, which divides the sedimentation tank (1) into a feeding trough and a discharging trough. The discharge trough of the sedimentation tank (1) is connected to one end of the inlet pipe (201), and the other end of the inlet pipe (201) is connected to the fermentation tank (3). The outlet of the fermentation tank (3) is connected to the inlet of the outlet pipe (301), the outlet of the outlet pipe (301) is connected to the inlet of the treatment tank (4), and the outlet of the treatment tank (4) is connected to the inlet of the reaction tank (5).

2. The vegetable processing effluent treatment apparatus according to claim 1, wherein An electric scraper (6) is provided at the top opening of the reaction tank (5).

3. The device for treating vegetable processing tail wastewater according to claim 1, characterized in that, The bottom of the reaction tank (5) is connected to the output port of the generator (7).

4. The device for treating vegetable processing tail wastewater according to claim 1, characterized in that, The water outlet pipe (501) at the bottom of the reaction tank (5) is also connected to the filter (8).

5. The device for treating vegetable processing tail wastewater according to claim 1, characterized in that, The reaction tank (5) is filled with PAC and PAM flocculants.

6. The vegetable processing effluent treatment apparatus according to claim 1, wherein The inlet pipe (201) is equipped with a one-way valve, which controls the flow direction to flow into the fermentation tank (3).

7. The device for treating vegetable processing tail wastewater according to claim 1, characterized in that, The outlet pipe (301) is equipped with a one-way valve, which controls the flow direction to flow into the treatment tank (4).

8. The device for treating vegetable processing tail wastewater according to claim 1, characterized by The treatment tank (4) is connected to an air pump (401), the outlet of the air pump (401) is connected to an exhaust pipe (402), and the exhaust pipe (402) is provided with several exhaust holes.

9. The vegetable processing wastewater treatment device according to claim 2, characterized in that, The electric scraper (6) is provided with a floc collection trough (10) below its end.

10. The device for treating vegetable processing tail wastewater according to claim 4, characterized by The filter (8) has one end of its outlet connected to the collection tank (9).

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