Advanced treatment process for driving organic matter removal to cooperate with microbial denitrification through manganese oxidation reduction

Abstract

The invention discloses an advanced treatment process for manganese oxidation reduction driven organic matter removal and microbial denitrification, and relates to the technical field of wastewater treatment. The process comprises the following steps: preparing and installing a required treatment system, wherein the treatment system comprises a water inlet tank, an up-flow bioreactor, a water outlet tank, an online automatic water quality detector and a computer terminal; preparing a functional filler which is an active MnO2 composite filler and / or a Bio-MnOx composite filler, mixing the functional filler with the natural manganese ore, and filling the filler area with the mixture; preparing a functional biological agent, and adding the functional biological agent into the up-flow bioreactor to start biofilm formation; when the effluent COD concentration is higher than 15 mg / L or the effluent TN concentration is higher than 5 mg / L, HR is prolonged for treatment, and when the effluent requirement is still not met after the HR is prolonged to 24 h, an enhancer Mn < 2 + > is added. The method is low in treatment energy consumption and low in cost, and belongs to a green low-carbon technology.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, and in particular to a deep treatment process for manganese redox-driven organic matter removal in synergistic microbial denitrification. Background Art

[0002] With the acceleration of urbanization, the problem of water shortage has become increasingly prominent. At the same time, the "water pollution-type water shortage" caused by poor water quality has further aggravated the scarcity of water resources. The treatment and reuse of sewage can alleviate the shortage of water resources to a certain extent, and it is also an important way to supplement and conserve water resources. However, with the improvement of my country's urbanization level and the continuous advancement of industrialization, the discharge of urban domestic sewage and industrial wastewater has continued to increase. At present, the secondary effluent of domestic sewage treatment plants still contains some organic matter that is difficult to be biodegraded. Among them, the residual humus and other organic matter are a type of macromolecular polycyclic aromatic compounds containing multiple functional groups such as phenolic hydroxyl and carboxyl, and are also key precursors for the formation of disinfection by-products. If it is discharged directly without treatment, it will lead to eutrophication of the water body and cause irreversible pollution to the water environment. Therefore, in order to ensure the water quality and ecological safety of the water system, urban sewage needs to be strictly treated before being discharged into the receiving water body.

[0003] At present, the secondary effluent deep treatment technology mainly covers two categories: physical and chemical treatment and biological treatment. Physical and chemical treatment methods include advanced oxidation, membrane separation and coagulation sedimentation. Although they can effectively remove pollutants, they have high energy consumption, large investment and are not conducive to low-carbon development. Biological treatment technologies mainly include biofilm method, biofilter and artificial wetland. The effluent produced by the biofilm method usually contains a large number of biofilm sheets and tiny biological fragments that are easy to precipitate. Due to the lack of biological flocculation ability similar to activated sludge, the effluent may be turbid. In contrast, biofilter and artificial wetland, as a green ecological technology, are widely used in municipal sewage treatment due to their low energy consumption and meeting low-carbon emission targets. However, this type of technology still faces the challenges of poor biodegradability of incoming water, difficulty in long-term stable operation and a single type of filling matrix during the treatment process, which limits its effectiveness and durability in large-scale applications.

[0004] For the above problems, the prior art has done relevant research, and the relevant patent applications are:

[0005] Application No. 201810286726.4 proposed an integrated device for high-efficiency deep treatment of wastewater with ultra-low discharge. It uses an integrated high-speed sedimentation tank and an electrochemical enhanced denitrification filter to effectively achieve the step-by-step deep removal of nitrogen, phosphorus, organic matter and suspended solids. However, this process requires high electrical energy, which increases the energy consumption cost of deep treatment. Biological treatment methods usually have the advantages of simple operation and green ecology. Application No. 201210031269.7 proposed a method for the synergistic treatment of difficult-to-degrade micropollutants by natural manganese ore-microorganisms. An anaerobic bioreactor using natural manganese ore as a filling layer was used to achieve effective removal of difficult-to-degrade organic pollutants in wastewater, including persistent pollutants (POPs), precursors of trihalomethanes (THMFPs), endocrine disruptors (EDCs), and pharmaceuticals and personal care products (PPCPs). However, the high-valent manganese content in the natural manganese ore filler of this method is low, and the treatment effect is limited. Application No. 202310304420.8 discloses a method and reactor for synchronously removing refractory organic matter by coupling manganese cycle and denitrification. The reactor uses MnO2 loaded by modified corn cobs as a functional filler, and achieves efficient removal of nitrate and refractory organic matter in water bodies by microbial-driven manganese redox cycle coupled denitrification. However, the loading capacity of corn cob-loaded MnO2 fillers is limited, and the preparation cost is high, which is not conducive to large-scale use.

[0006] This shows that the prior art needs to be further improved. Summary of the invention

[0007] The purpose of the present invention is to provide a deep treatment process for manganese redox-driven organic matter removal and synergistic microbial denitrification. The refractory organic matter in the wastewater is oxidized by high-valent manganese to improve its bioavailability, and the oxidized organic matter and reduced manganese ions can be used as electron donors for microbial denitrification, thereby achieving the removal of refractory organic matter and deep denitrification of wastewater, and at the same time achieving manganese circulation under biochemical action.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] A deep treatment process for manganese redox-driven organic matter removal and synergistic microbial denitrification, comprising the following steps:

[0010] a. Preparation of functional fillers

[0011] The functional filler is an active MnO2 composite filler and / or a Bio-MnOx composite filler, and the value of x is 1 to 2;

[0012] b. Prepare the required processing system

[0013] The treatment system comprises a water inlet tank, an upflow bioreactor, a water outlet tank, an online automatic water quality detector and a computer terminal, wherein the online automatic water quality detector is connected to the water inlet tank and the water storage tank respectively; the water inlet tank is connected to the water inlet at the lower side of the upflow bioreactor, and the water outlet tank is connected to the water outlet at the upper side of the upflow bioreactor; the upflow bioreactor comprises a reactor body, wherein the reactor body is cylindrical, a porous partition is arranged in the reactor body, a filler area is above the porous partition, and a water distribution area is below the porous partition;

[0014] The functional filler and the natural manganese ore are mixed in a volume ratio of 1:5-10 and filled in the filler area;

[0015] c. Preparation of functional biological agents

[0016] c1. Directed domestication of manganese oxidizing bacteria: Use the municipal sewage to be treated with glucose as the culture carrier, anaerobic activated sludge as the inoculum, and add 30-50 mg / L MnCl2. Perform anaerobic shaking culture for 2-5 days until Mn in the supernatant is reduced. 2+ When the concentration is 5-15 mg / L, the directional domestication is successful;

[0017] c2. Directed domestication of manganese-reducing bacteria: Use the municipal sewage to be treated with glucose as the culture carrier, anaerobic activated sludge as the inoculum, and add 0.6-1 g / L MnO2. Perform anaerobic shaking culture for 2-5 days until Mn in the supernatant is reduced. 2+ When the concentration is 10-15 mg / L, the directional domestication is successful;

[0018] The manganese oxidizing bacterial agent and the manganese reducing bacterial agent are mixed in a volume ratio of 1:1 to obtain a functional biological bacterial agent;

[0019] d. Adding the functional biological agent into the upflow bioreactor to start biofilm formation;

[0020] e. The pH of the water to be treated is 4.0-9.0, the water temperature is 5-30℃, and the water is introduced through the water inlet of the upflow bioreactor. The HRT is 4-24h, and the COD and TN concentrations of the system effluent are maintained at 5-15mg / L and 1-5mg / L respectively;

[0021] When the effluent COD concentration is higher than 15mg / L or the effluent TN concentration is higher than 5mg / L, the HR value is extended for treatment. If it still does not meet the effluent requirements after 24h, the enhancer Mn is added. 2+ .

[0022] In the above-mentioned deep treatment process for manganese redox-driven organic matter removal and synergistic microbial denitrification, in step a, the preparation method of the active MnO2 composite filler is: under room temperature, add a carrier to a mixed solution of 0.1-0.2M KMnO4 and 0.1-0.42M NaOH, and stir continuously. After 10-30 minutes, add 0.1-0.2M MnCl2 solution dropwise to the obtained mixed system to react. After the reaction is completed, let it stand for 3-6 hours, dilute and wash, and place it to dry.

[0023] In the above-mentioned deep treatment process for manganese redox-driven organic matter removal and coordinated microbial denitrification, the carrier is natural manganese ore or a porous matrix, and the porous matrix is ​​a porous volcanic rock or a porous filler; the volume ratio of the carrier to the mixed solution of KMnO4 and NaOH is 0.2-1:1, and the volume ratio of KMnO4, NaOH and MnCl2 is 12:4:3.

[0024] The above-mentioned deep treatment process of manganese redox driven organic matter removal and synergistic microbial denitrification, Bio-MnO x The preparation method of the composite filler is as follows: prepare LB culture medium, introduce manganese oxidizing bacteria Pseudomonas putidaMnB6 into the LB culture medium at 28°C, culture for 6 to 8 hours under shaking at 120 rpm, and then introduce 5 to 15 mg / L Mn 2+ Then, add a certain amount of carrier and soak for 24 to 48 hours, then take it out and rinse it twice with pH = 7 biological phosphate buffer.

[0025] In the above-mentioned deep treatment process for manganese redox-driven organic matter removal and synergistic microbial denitrification, the upflow bioreactor is made of plexiglass, the porous partition is 10 cm away from the bottom of the reactor body, the height of the packing layer in the packing area is 70 cm, and above the packing area is a water storage layer with a height of 20 cm.

[0026] The above-mentioned manganese redox-driven organic matter removal and microbial denitrification deep treatment process detects COD and TN of the water inlet and outlet tanks through an online automatic water quality detector, and the online automatic water quality detector is connected to a computer terminal.

[0027] In the above-mentioned deep treatment process of manganese redox driven organic matter removal and synergistic microbial denitrification, the particle size of the filler after mixing is 0.5-2 cm; the treatment system has a COD removal rate of 60-95% and a TN removal rate of 65-90%.

[0028] In the above-mentioned deep treatment process for manganese redox-driven organic matter removal and synergistic microbial denitrification, in step d, biofilm startup includes: (1) in the aneroid stage, the activated sludge of the sewage treatment plant is mixed with the functional biological agent as the inoculated sludge, the volume ratio of the activated sludge to the functional biological agent is 10:1, the inoculated sludge is filled into the upflow bioreactor, after aneroid exposure for 24 to 48 hours, the sludge in the upflow bioreactor is emptied, and the upflow bioreactor is filled with activated sludge again. This process is repeated for 4 to 7 days to complete the initial biofilm formation; (2) the outlet of the water inlet tank supplies water to the upflow bioreactor at a rate of 0.2 to 1.0 L / h, operates for 8 to 12 hours, and lasts for 4 to 7 days; (3) the outlet of the water inlet tank supplies water to the upflow bioreactor at a rate of 0.5 to 2.0 L / h, operates for 15 days, the biofilm is loaded on the filler, and the biofilm formation is completed.

[0029] The above-mentioned deep treatment process of manganese redox driven organic matter removal and synergistic microbial denitrification, adding the enhancer Mn 2+ The amount of Mn at the outlet must be ensured 2+ Concentration ≤0.1mg / L.

[0030] In the above-mentioned deep treatment process for manganese redox-driven organic matter removal and synergistic microbial denitrification, a peristaltic pump is arranged on the water inlet pipe connecting the water inlet tank and the upflow bioreactor.

[0031] Compared with the prior art, the present invention brings the following beneficial technical effects:

[0032] (1) The present invention proposes a deep treatment process for organic matter removal driven by manganese redox and coordinated microbial denitrification, wherein a functional filler is added into an upflow bioreactor, and the functional filler is an active MnO2 composite filler and / or Bio-MnO x Composite fillers, functional fillers have strong oxidation ability, can improve the biodegradability of difficult-to-degrade organic matter and release manganese ions, which can enable microorganisms to use the difficult-to-use organic matter in sewage and the released manganese ions as electron donors for denitrification reactions, thereby achieving the simultaneous removal of difficult-to-degrade organic matter and total nitrogen. In addition, natural manganese ore has a high specific surface area and contains more high-valent manganese. Therefore, it has a strong adsorption and oxidation ability. While providing microbial attachment sites, it can also use its adsorption and high-valent manganese oxidation to remove some difficult-to-degrade organic matter. The carrier for preparing functional fillers, such as natural manganese ore / porous matrix, is abundant in resources, affordable, and has good adsorption and oxidation efficiency.

[0033] (2) Functional biological agents are obtained by acclimating anaerobic activated sludge from sewage treatment plants, and biofilm formation is carried out using a mixture of functional biological agents and anaerobic activated sludge. The mixed sludge contains indigenous bacteria and enriched functional bacterial communities (manganese oxidizing agents and manganese reducing agents). No external bacterial source is required, which enables microorganisms to quickly adapt to the environment and play their role, thereby shortening the reactor startup time and improving the reaction efficiency.

[0034] (3) The multivalent changes of manganese were achieved under biochemical action No secondary pollution will be generated, and it is suitable for large-scale treatment. The water inlet and outlet tanks of the upflow bioreactor of the present invention are equipped with online automatic water quality detectors to monitor the water quality (COD and TN) of the inlet and outlet water in real time, and can be operated visually and managed conveniently.

[0035] (4) The method of the present invention realizes online monitoring of the water quality of the water inlet tank and the water outlet tank through an online automatic water quality detector, which is beneficial to operation management. The processing energy consumption of the present invention is low, the cost is low, and it belongs to green and low-carbon technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The present invention will be further described below in conjunction with the accompanying drawings:

[0037] Figure 1 This is a schematic diagram of the processing system structure required for the present invention.

[0038] Figure 2 The following are statistical graphs of COD concentration changes in inlet and outlet water of Example 1, Example 2, Example 3 of the present invention and Comparative Example 1 and Comparative Example 2.

[0039] Figure 3 It is a statistical chart of the changes in COD removal rates of the effluent of Example 1, Example 2, Example 3 of the present invention and Comparative Example 1 and Comparative Example 2.

[0040] Figure 4 It is a statistical graph of the changes in TN concentration of the inlet and outlet water of Example 1, Example 2, Example 3 of the present invention and Comparative Example 1 and Comparative Example 2.

[0041] Figure 5 It is a statistical chart of the changes in TN removal rates of the effluents of Example 1, Example 2, Example 3 of the present invention and Comparative Example 1 and Comparative Example 2.

[0042] Figure 6 This is a graph showing the changes in COD and TN inlet and outlet water concentrations and removal rates before and after water treatment regulation in Example 1 of the present invention.

[0043] In the figure: 1. peristaltic pump, 2. porous partition, 3. packing layer, 4. exhaust pipe, 5. valve, 6. online automatic water quality detector, 7. water inlet tank, 8. water outlet tank. DETAILED DESCRIPTION

[0044] The present invention proposes a deep treatment process for manganese redox-driven organic matter removal and coordinated microbial denitrification. In order to make the advantages and technical solutions of the present invention clearer and more specific, the present invention is further described below in conjunction with specific embodiments.

[0045] It is understandable that the connection relationship described in this application refers to direct or indirect connection. For example, the connection between A and B can be either a direct connection between A and B or an indirect connection between A and B through one or more other electrical components. For example, A and C can be directly connected, and C and B can be directly connected, so that A and B are connected through C. It is also understandable that the "A connects B" described in this application can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.

[0046] In the description of this application, unless otherwise specified, " / " means "or", for example, A / B can mean A or B. "And / or" in this article is only a way to describe the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0047] The main technical concept of the present invention is that: by putting the self-made functional filler into the upflow bioreactor, the organic matter can be better degraded and the total nitrogen can be removed simultaneously; in addition, the functional biological agent is obtained by acclimating the anaerobic activated sludge of the sewage plant, which does not require an external bacterial source, that is, it can enable the microorganisms to quickly adapt to the environment and play their role; the online automatic water quality detector connected to the water inlet tank and the water storage tank can realize the online monitoring of the COD and TN of the inlet and outlet water.

[0048] The "carrier" mentioned in the present invention is natural manganese ore or a porous matrix, and the porous matrix is ​​a porous volcanic stone or a porous filler.

[0049] like Figure 1As shown, a deep treatment system for manganese redox-driven organic matter removal and coordinated microbial denitrification of the present invention comprises an upflow bioreactor, a peristaltic pump 1, a porous partition 2, a packing layer 3, an exhaust pipe 4, a valve 5, an online automatic water quality detector 6, a water inlet box 7, and a water outlet box 8. The upflow bioreactor comprises a reactor body, which is made of organic glass, 100 cm high and 25 cm in inner diameter. A porous partition 2 is arranged in the reactor body, and the porous partition is 10 cm away from the bottom of the reactor body. Below the porous partition is a water distribution area. The water inlet of the reactor body is located on the side wall of the reactor body below the porous partition, that is, water is introduced from the bottom. A peristaltic pump 1 is arranged on the pipeline connecting the water inlet of the reactor body and the water inlet box 7; above the porous partition is a packing area, the height of the packing layer in the packing area is 70 cm, the packing layer is the functional packing prepared by the present invention, and a water storage layer with a height of 20 cm is left above the packing layer. In addition, the water inlet tank and the water outlet tank are connected to an online automatic water quality detector 6 for online water quality (COD, TN) detection.

[0050] The present invention is further described below in conjunction with the above system.

[0051] Embodiment 1:

[0052] This embodiment can be applied to municipal sewage with a COD (chemical oxygen demand) concentration of 15 to 25 mg / L, a TN (total nitrogen) concentration of 10 to 20 mg / L, a pH range of 6.5 to 7.5, and a water temperature of 15 to 25°C. The COD and TN concentrations of the system effluent are 1 to 3 mg / L and 1 to 3 mg / L, respectively. The removal rate of COD reaches 88 to 95%, and the removal rate of TN reaches 83 to 90%, thereby achieving deep purification of municipal sewage.

[0053] The structure of the deep processing system required in this embodiment is as follows Figure 1 shown.

[0054] A deep treatment process for manganese redox-driven organic matter removal and synergistic microbial denitrification, comprising the following steps:

[0055] a. Preparation of functional fillers

[0056] The functional filler is an active MnO2 composite filler: under room temperature, add natural manganese ore / porous matrix to a mixture of 0.1-0.2M KMnO4 and 0.1-0.42M NaOH (the volume ratio of natural manganese ore / porous matrix to the mixture is 0.2-1:1), stir continuously, and after 10-30 minutes, add 0.1-0.2M MnCl2 solution dropwise to the mixture (the volume ratio is KMnO4:NaOH:MnCl2=12:4:3). After the reaction, the mixture is allowed to stand for 3-6 hours. Dilute, wash, and dry.

[0057] b. Prepare and install the above treatment system

[0058] The functional filler and the natural manganese ore are mixed in a volume ratio of 1:5 to 10 and filled in the filler area;

[0059] c. Preparation of functional biological agents

[0060] c1. Directed domestication of manganese oxidizing bacteria: Use treated municipal sewage with 30-50 mg / L glucose as the culture medium, anaerobic activated sludge as the inoculum (20%-50%, v / v), and add 30-50 mg / L MnCl2. Culture at 35°C with anaerobism and shaking for 2-5 days until Mn in the supernatant is reduced to 0. 2+ When the concentration is 5-15 mg / L, the directional domestication is successful;

[0061] c2. Directed domestication of manganese-reducing bacteria: Use municipal sewage to be treated with 30-50 mg / L glucose as the culture medium, anaerobic activated sludge as the inoculum (20%-50%, v / v), and add 0.6-1 g / L MnO2. Culture at 35°C with anaerobism and shaking for 2-5 days until Mn in the supernatant is reduced to 0. 2+ When the concentration is 10-15 mg / L, the directional domestication is successful;

[0062] The manganese oxidizing bacterial agent and the manganese reducing bacterial agent are mixed in a volume ratio of 1:1 to obtain a functional biological bacterial agent;

[0063] d. Adding the functional biological agent into the upflow bioreactor to start biofilm formation;

[0064] The biofilm formation start-up of the system is divided into three stages: the first stage is the exposure stage. The anaerobic activated sludge from the sewage plant and the functional biological agent are mixed in a volume ratio of 10:1 as the inoculated sludge and filled with the upflow bioreactor. After 24 to 48 hours of exposure, the sludge in the upflow bioreactor is emptied and the activated sludge is filled again. This process is repeated for about 4 to 7 days to complete the initial biofilm formation.

[0065] The second stage is the small flow continuous water inlet stage. The inlet water is the municipal sewage to be treated. The outlet of the water inlet tank supplies water to the upward flow bioreactor at 0.2-1.0L / h, and runs continuously for 8-12 hours. This stage lasts for about 3-7 days. In the early stage of biofilm formation, the microbial load is not firm. Excessive flow can easily cause the biofilm loaded on the filler to fall off during the exposure stage, affecting the biofilm formation effect.

[0066] The third stage is the operation and acclimation stage within the design parameter range. The influent is the municipal sewage to be treated, and a large influent flow rate is set for continuous operation (the flow rate is controlled within the effective operation range and should not be too large, and the HRT of the upflow bioreactor is set to 2-6h), and the microorganisms in the upflow bioreactor are further propagated and acclimated. The system runs for about 15 days, and the effluent reaches a stable state. At this time, the biofilm can be seen on the filler in the system, that is, the biofilm is successfully formed.

[0067] e. Water treatment regulation:

[0068] The pH of municipal sewage to be treated is 6.5-7.5, the water temperature is 20-25℃, and water is introduced through the water inlet of the upflow bioreactor. The HRT is 6-24h, and the COD and TN concentrations of the system effluent are maintained at 15-25mg / L and 10-20mg / L respectively;

[0069] When the effluent COD concentration is higher than 15mg / L or the effluent TN concentration is higher than 5mg / L, the HRT value is extended for treatment. If it still does not meet the effluent requirements after 24h, the enhancer Mn is added. 2+ , add 5-15 mg / L Mn(Ⅱ) to the water inlet tank (it is necessary to ensure that the effluent Mn(Ⅱ) does not exceed 0.1 mg / L) to improve the treatment efficiency of the upflow bioreactor. When the treatment efficiency reaches the effluent requirements and stabilizes for 3-5 days, stop adding the enhancer Mn 2+ , maintaining efficient operation of the upflow bioreactor.

[0070] The specific steps for building and starting the processing system of the present invention in this embodiment are as follows:

[0071] Step 1: Prepare active MnO2 composite filler. Under room temperature, add natural manganese ore with a particle size of 10-15 mm to a mixture of 0.2M KMnO4 and 0.42M NaOH (the volume ratio of natural manganese ore to the mixture is 1:1), stir continuously for 30 minutes, add 0.2M MnCl2 solution dropwise to the mixed system (the volume ratio is KMnO4: NaOH: MnCl2 = 12:4:3), continue to stir continuously for 1 hour, and after the reaction, let the mixed system stand for 6 hours. Then wash with tap water until the pH of the leaching solution is close to neutral, and place it at room temperature to dry for 48 hours to obtain the active MnO2 composite filler.

[0072] Step 2: Mix the active MnO2 composite filler prepared in the previous step with 10-15 mm natural manganese ore in a volume ratio of 1:5, and load it into the filler layer of the upflow bioreactor to form a manganese redox-driven organic matter removal and synergistic microbial denitrification system.

[0073] Step 3: preparing functional biological agents;

[0074] Step 3a: Use the municipal sewage to be treated with 50 mg / L glucose as the culture carrier and the anaerobic activated sludge from the sewage treatment plant as the inoculum (50%, the volume ratio of the culture carrier to the inoculum is 1:1). After mixing the culture carrier and the inoculum, add 30 mg / L MnCl2 solution thereto, and culture at 35°C for 2 to 5 days with anaerobism and shaking until Mn in the supernatant is reduced to 0. 2+ When the concentration is 5-15 mg / L, the directional domestication is successful and the manganese oxidizing bacteria agent is obtained;

[0075] Step 3b: Use the municipal sewage to be treated with 50 mg / L glucose as the culture carrier, anaerobic activated sludge as the inoculum (50%, the volume ratio of culture carrier to inoculum is 1:1), and add 1 g / L MnO2, and culture at 35°C for 2 to 5 days with anaerobism and shaking until Mn in the supernatant is 1. 2+ When the concentration is 10-15 mg / L, the directional domestication is successful and the manganese-reducing bacteria agent is obtained;

[0076] Step 3c: mixing the manganese oxidizing bacterial agent and the manganese reducing bacterial agent in a volume ratio of 1:1 to obtain a functional biological bacterial agent;

[0077] Step 4: Mix the anaerobic activated sludge from the sewage treatment plant with the functional biological agent in a volume ratio of 10:1 to obtain inoculated sludge.

[0078] Step 5: Start-up and operation of manganese redox-driven organic matter removal and microbial denitrification system;

[0079] Step 5a: using the inoculated sludge in step 4 to start the biofilm formation in the upflow bioreactor, and starting the upflow bioreactor by aeration culture, continuous water inflow at a small flow rate of 1 L / h and a large flow rate of 2 L / h, and the manganese oxide-microorganism fixation stage;

[0080] The experimental water is the effluent from the secondary sedimentation tank of a sewage plant. The water quality indicators are shown in Table 1:

[0081] Table 1

[0082]

[0083] Step 6: After the upflow bioreactor is successfully started, during the stable operation period, the experimental water in the water inlet tank is introduced into the upflow bioreactor through a peristaltic pump, and it is continuously operated in a laboratory at 20-30°C, with a hydraulic retention time of 12h;

[0084] Step 7: After the upflow bioreactor is running stably, online monitoring is used to regularly monitor the changes of pollutants such as COD and TN, as well as the organic matter removal rate and denitrification efficiency of the manganese redox-driven organic matter removal synergistic microbial denitrification system.

[0085] Step 8: After the manganese redox-driven organic matter removal and synergistic microbial denitrification system has been running for 300 days, if the treatment effect deteriorates, 10 mg / L Mn(Ⅱ) (prepared by MnCl2) is added to the inlet tank (it is necessary to ensure that the effluent Mn(Ⅱ) does not exceed 0.1 mg / L) to improve the treatment efficiency of the upflow bioreactor. When the treatment efficiency reaches the effluent requirements and stabilizes for 3 days, stop adding the enhancer Mn 2+ , maintaining the efficient operation of the upflow bioreactor. The water treatment regulation results are as follows Figure 6 shown.

[0086] The results show that the average removal rate of COD by the upflow bioreactor in this embodiment can reach 87%, and the average removal rate of TN is as high as 86%. Figure 2 to Figure 5 As shown. It shows that the manganese redox driven organic matter removal synergistic microbial denitrification system of this embodiment has excellent removal of various pollutants. When the treatment effect of the upflow bioreactor is reduced, after adding the Mn (II) enhancer, the upflow bioreactor restores the original treatment effect and continues to work stably. Figure 6 As shown, the effectiveness of the water treatment control method is demonstrated.

[0087] Embodiment 2:

[0088] The difference between this embodiment and embodiment 1 is that:

[0089] The functional filler used is Bio-MnO x Composite filler, x value is 1-2; its preparation process is as follows:

[0090] Step 1: Prepare LB medium, introduce manganese oxidizing bacteria Pseudomonas putida MnB6 (BCCM / LMG 2322) into LB medium at 28°C and culture under shaking at 120 rpm for 6-8 hours, then introduce 15 mg / L Mn(II) and then add a certain amount of natural manganese ore with a particle size of 10-15 mm (the volume ratio of natural manganese ore to LB medium is 1:1), soak for 24-48 hours, take out the natural manganese ore, rinse twice with 10 mM biological phosphate buffer (pH=7), and obtain Bio-MnO x Composite fillers.

[0091] Step 2: Prepare the Bio-MnO x The composite filler is mixed with 10-15 mm natural manganese ore in a volume ratio of 1:5 and loaded into the filler layer of the upflow bioreactor to form a manganese redox-driven organic matter removal and microbial denitrification system.

[0092] The results show that the average removal rate of COD by the upflow bioreactor in this embodiment can reach more than 90%, and the average removal rate of TN is as high as 87%. Figure 2 to Figure 5 It is shown that the manganese redox driven organic matter removal synergistic microbial denitrification system of this embodiment also has excellent removal effect on various pollutants.

[0093] Embodiment 3:

[0094] The difference between this embodiment and embodiment 1 is that:

[0095] The functional filler used is a mixed filler of active MnO2 composite filler and Bio-MnOx composite filler; its preparation process is as follows:

[0096] Step 1: Prepare active MnO2 composite filler. Under room temperature, add natural manganese ore with a particle size of 10-15 mm to a mixture of 0.2M KMnO4 and 0.42M NaOH (the volume ratio of natural manganese ore to the mixture is 1:1), stir continuously for 30 minutes, add 0.2M MnCl2 solution dropwise to the mixed system (the volume ratio is KMnO4: NaOH: MnCl2 = 12:4:3), continue to stir continuously for 1 hour, and after the reaction, let the mixed system stand for 6 hours. Then wash with tap water until the pH of the leaching solution is close to neutral, and place it at room temperature to dry for 48 hours to obtain the active MnO2 composite filler.

[0097] Step 2: Prepare LB medium, introduce manganese oxidizing bacteria Pseudomonas putida MnB6 (BCCM / LMG 2322) into LB medium at 28°C and culture under shaking at 120 rpm for 6-8 hours, then introduce 15 mg / L Mn(II) and then add a certain amount of natural manganese ore with a particle size of 10-15 mm (the volume ratio of natural manganese ore to LB medium is 1:1), soak for 24-48 hours, take out the natural manganese ore, rinse twice with 10 mM biological phosphate buffer (pH=7), and obtain Bio-MnO x Composite fillers.

[0098] Step 3: Prepare the active MnO2 composite filler and Bio-MnO prepared in step 1 and step 2. x The composite filler is mixed with 10-15 mm natural manganese ore in a volume ratio of 1:1:10 and loaded into a filler layer of an upflow bioreactor to form a manganese redox-driven organic matter removal and microbial denitrification system.

[0099] The results show that the average removal rate of COD and TN in the upflow bioreactor of this embodiment can reach 89% and 87%, respectively. Figure 2 to Figure 5It is shown that the manganese redox driven organic matter removal synergistic microbial denitrification system of this embodiment also has excellent removal effect on various pollutants.

[0100] Comparative Example 1:

[0101] The difference between Comparative Example 1 and Example 1 is that the filler used is natural manganese ore with a particle size of 10 to 15 mm, and the specific system construction steps are as follows:

[0102] Step 1: Fill 10-15 mm natural manganese ore into the packing layer of the upflow bioreactor to form a microbial denitrification system.

[0103] The results show that the average removal rate of COD and TN in the upflow bioreactor of comparative example 1 is only 70%, and the average removal rate of TN is 68%. Figure 2 to Figure 5 It is shown that the removal effect of various pollutants by the biological denitrification system of Comparative Example 1 is significantly worse than that of the manganese redox driven organic matter removal synergistic microbial denitrification system of Examples 1, 2 and 3 of the present invention.

[0104] Comparative Example 2:

[0105] The difference between Comparative Example 2 and Example 1 is that the inoculum sludge used is untamed anaerobic activated sludge from a sewage treatment plant, and the specific system startup steps are as follows: Step 1: Use anaerobic activated sludge from a sewage treatment plant as inoculum sludge to start the upflow bioreactor for biofilm formation, and start the upflow bioreactor through aeration cultivation, continuous water inflow at a small flow rate of 1L / h and a large flow rate of 2L / h, and a fixed stage.

[0106] The results show that the average removal rate of COD and TN in the upflow bioreactor of comparative example 2 is only 75%, and the average removal rate of TN is 73%. Figure 2 to Figure 5 It is shown that the removal effect of various pollutants by the upflow bioreactor of Comparative Example 2 is significantly worse than that of the manganese redox driven organic matter removal synergistic microbial denitrification system of Examples 1, 2 and 3 of the present invention.

[0107] The removal effects of COD and TN of the experimental water by continuous and stable operation of Example 1, Example 2, Example 3, Comparative Example 1 and Comparative Example 2 for 30 days are shown in Table 2:

[0108] Table 2

[0109]

[0110] According to the results of the above examples and comparative examples, a manganese redox-driven organic matter removal and microbial denitrification deep treatment process proposed by the present invention can be achieved by using a homemade active MnO2 composite filler and Bio-MnO xThe composite filler and the functional bacterial agent enable the upflow bioreactor to degrade organic matter more efficiently and remove total nitrogen simultaneously. In addition, the functional filler prepared in the invention is of suitable price, has good adsorption and oxidation efficiency, and uses mixed sludge of functional biological bacterial agent and anaerobic activated sludge for biofilm formation. The mixed sludge contains indigenous bacteria and enriched functional bacterial flora, which can enable microorganisms to quickly adapt to the environment and play their role, thereby shortening the reactor startup time and improving the reaction efficiency. In summary, the present invention has good treatment effect, low energy consumption, low cost, and belongs to green and low-carbon technology.

[0111] Parts not described in the present invention can be implemented by referring to the existing technology.

[0112] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present application and are not intended to be limiting of the present application. As long as they are within the spirit of the present application, appropriate changes and modifications to the above embodiments should fall within the scope of protection of the claims of the present application.

Claims

1. A deep treatment process for organic matter removal driven by manganese redox and coordinated microbial denitrification, characterized in that: The following steps are involved: a. Preparation of functional fillers The functional filler is an active MnO2 composite filler and / or a Bio-MnOx composite filler, and the value of x is 1 to 2; b. Prepare the required processing system The treatment system comprises a water inlet tank, an upflow bioreactor, a water outlet tank, an online automatic water quality detector and a computer terminal, wherein the online automatic water quality detector is connected to the water inlet tank and the water storage tank respectively; the water inlet tank is connected to the water inlet at the lower side of the upflow bioreactor, and the water outlet tank is connected to the water outlet at the upper side of the upflow bioreactor; the upflow bioreactor comprises a reactor body, wherein the reactor body is cylindrical, a porous partition is arranged in the reactor body, a filler area is above the porous partition, and a water distribution area is below the porous partition; The functional filler is mixed with natural manganese ore in a volume ratio of 1:5-10 and filled in the filler area; c. Preparation of functional biological agents c1. Directed domestication of manganese oxidizing bacteria: Use the municipal sewage to be treated with glucose as the culture carrier, anaerobic activated sludge as the inoculum, and add 30-50 mg / L MnCl2. Perform anaerobic shaking culture for 2-5 days until Mn in the supernatant is reduced. 2+ When the concentration is 5-15 mg / L, the directional domestication is successful; c2. Directed domestication of manganese-reducing bacteria: Use the municipal sewage to be treated with glucose as the culture carrier, anaerobic activated sludge as the inoculum, and add 0.6-1 g / L MnO2. Perform anaerobic shaking culture for 2-5 days until Mn in the supernatant is reduced. 2+ When the concentration is 10-15 mg / L, the directional domestication is successful; The manganese oxidizing bacterial agent and the manganese reducing bacterial agent are mixed in a volume ratio of 1:1 to obtain a functional biological bacterial agent; d. Adding the functional biological agent into the upflow bioreactor to start biofilm formation; e. The pH of the water to be treated is 4.0-9.0, the water temperature is 5-30℃, and the water is introduced through the water inlet of the upflow bioreactor. The HRT is 4-24h, and the COD and TN concentrations of the system effluent are maintained at 5-15mg / L and 1-5mg / L respectively; When the effluent COD concentration is higher than 15mg / L or the effluent TN concentration is higher than 5mg / L, the HR is extended for treatment. If it still does not meet the effluent requirements after 24h, the enhancer Mn is added. 2+ .

2. The deep treatment process of manganese redox driven organic matter removal and microbial denitrification according to claim 1, characterized in that: In step a, the preparation method of the active MnO2 composite filler is: under room temperature, add a carrier to a mixed solution of 0.1-0.2M MmnO4 and 0.1-0.42M NaOH, and stir continuously. After 10-30 minutes, add 0.1-0.2M MnCl2 solution dropwise to the obtained mixed system to react. After the reaction is completed, let it stand for 3-6 hours, dilute and wash, and place it to dry.

3. A deep treatment process for organic matter removal driven by manganese redox and coordinated microbial denitrification according to claim 2, characterized in that: The carrier is natural manganese ore or a porous matrix, and the porous matrix is ​​porous volcanic stone or porous filler; the volume ratio of the carrier to the mixed solution of KMnO4 and NaOH is 0.2-1:1, and the volume ratio of KMnO4, NaOH and MnCl2 is 12:4:

3.

4. The deep treatment process of manganese redox driven organic matter removal and microbial denitrification according to claim 1, characterized in that: Bio-MnO x The preparation method of the composite filler is as follows: prepare LB culture medium, introduce manganese oxidizing bacteria Pseudomonas putida MnB6 into the LB culture medium at 28°C, culture for 6 to 8 hours under shaking at 120 rpm, and then introduce 5 to 15 mg / L Mn 2+ Then, add a certain amount of carrier and soak for 24 to 48 hours, then take out and rinse twice with pH = 7 biological phosphate buffer to obtain the product.

5. The deep treatment process of manganese redox driven organic matter removal and microbial denitrification according to claim 1, characterized in that: The upflow bioreactor is made of plexiglass, the porous partition is 10 cm away from the bottom of the reactor body, the height of the packing layer in the packing area is 70 cm, and the water storage layer is above the packing area, and the height of the water storage layer is 20 cm.

6. The deep treatment process of manganese redox driven organic matter removal and microbial denitrification according to claim 1, characterized in that: The COD and TN of the water inlet tank and the water outlet tank are detected by an online automatic water quality detector, and the online automatic water quality detector is connected to a computer terminal.

7. The deep treatment process of manganese redox driven organic matter removal and microbial denitrification according to claim 1, characterized in that: The particle size of the filler after mixing is 0.5 to 2 cm; the removal rate of the treatment system for COD reaches 60 to 95%, and the removal rate for TN reaches 65 to 90%.

8. The deep treatment process of manganese redox driven organic matter removal and microbial denitrification according to claim 1, characterized in that: In step d, biofilm formation start-up includes: (1) in the stage of ventilating, the activated sludge of the sewage treatment plant is mixed with the functional biological agent as the inoculated sludge, the volume ratio of the activated sludge to the functional biological agent is 10:1, the inoculated sludge is filled into the upflow bioreactor, after ventilating for 24 to 48 hours, the sludge in the upflow bioreactor is emptied, and the upflow bioreactor is filled with activated sludge again, and this process is repeated for 4 to 7 days to complete the preliminary biofilm formation; (2) the outlet of the water inlet tank supplies water to the upflow bioreactor at a rate of 0.2 to 1.0 / L, operates for 8 to 12 hours, and continues for 4 to 7 days; (3) the outlet of the water inlet tank supplies water to the upflow bioreactor at a rate of 0.5 to 2.0 / L, operates for 15 days, the biofilm is loaded on the filler, and the biofilm formation is completed.

9. The deep treatment process of manganese redox driven organic matter removal and microbial denitrification according to claim 1, characterized in that: Adding strengthening agent Mn 2+ The amount of Mn at the outlet must be ensured 2+ Concentration ≤0.1mg / L.

10. The deep treatment process of manganese redox driven organic matter removal and microbial denitrification according to claim 1, characterized in that: A peristaltic pump is arranged on the water inlet pipeline connecting the water inlet tank and the upflow bioreactor.

Images